* GB785578 (A)

Description: GB785578 (A) ? 1957-10-30

Improvements in or relating to electron discharge devices of the beamstorage type

Description of GB785578 (A)

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BE544938 (A) DE971205 (C) FR1137636 (A) NL99291 (C) US2844722 (A) BE544938 (A) DE971205 (C) FR1137636 (A) NL99291 (C) US2844722 (A) less Translate this text into Tooltip

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The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

PATENT SPECIFICATION Dateof Aplicatofn and filing 7 om SpecificationJ an 852568 Dae of Application an iig Complete Spcfcto a 2,1956. I ' A l l I No 2743156. Application made in United States of America on Feb 4, 1955. Complete Specification Published Oct 30, 1957. Index at Acceptance:-Classes 39 ( 1), D 4 (A 1: A 7: F 1 F: Fi G: F 1 J: G 4: K 4: K 5); C( 1 B: 2 B 1 2 B 3: 2 K: 5: 6). International Classification: -GO 6 f H Olj. and 106 ( 1), COMPLETE SPECIFICATION Improvements in or relating to Electron Discharge Devices of the Beam Storage Type We, WESTERN ELECTRIC COMPANY, INCORPORATED, of 195, Broadway, New York City, New York State, United States of America, a

corporation of the State of New York, United States of America, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to electron discharge devices of the beam storage type and more particularly to the reading and writing of information in such devices. One type of fast access short storage memory that has been employed in recent memory or storage systems utilizes electron discharge devices of the beam storage type and particularly of the type known as a barrier-grid storage tube Such tubes are well known in the art, being described, for example, in an article " Barrier-Grid Storage Tube and its Operation" by A S Jensen, J P Smith, M H. Mesner, and L E Flory, R C A Review IX, pp 112-135, March, 1948, and in United States Patent Specification No 2,675,499. In a barrier grid storage tube, a target, such as a dielectric sheet, has a conductive electrode or back plate secured to one face thereof An electron gun projects a concentrated electron stream against the other face of the dielectric through a barrier grid which is positioned directly adjacent this other face of the dielectric In the operation of such a tube, the beam is deflected in two coordinate directions; for example it may be repeatedly swept in one direction and selectively deflected in the other direction or it may be turned on and deflected to a particular spot on the dielectric surface if completely random access is desired The operation of the device involves, basically, two cycles, one store or write and the other remove or read During the writing cycle the potential or charge of elemental areas of the b amirr A dielectric surface is varied in accordance vith an input signal, the charge change being dependent on the signal at the time the beam impinges on the area During the reading cycle, the charges upon these areas are removed by action of the electron beam. Fundamentally the charging and discharging of the elemental areas above noted result from the emission of secondary electrons The flow of secondary electron current can be detected in several ways and provides an output indication of the stored information during the reading cycle Generally the method of operation of the barrier grid storage tube has been to read the signals stored on the target by detecting variations in the current to a large collector electrode placed in front of the oarrier grid and dielectric surface, the current to the collector electrode being due to secondary electrons released from the dielectric surface and passing through the barrier grid. Several major problems arise in this type of operation, however First,

the signal received at the collector is very small, not all of the emitted secondaries being collected at the collector electrode Secondly, and more serious, the fractional amount of such collection is dependent on the position of origin in the storage array Thus there are variations in the size of the signal at the collector as a function of spot position on the dielectric surface independent of the stored information This effect is called ">shading " Shading appears as a decrease in magntiude of the reading signal as the spot approaches the edge of the target and is caused mostly by decrease in collector efficiency A third disadvantage in this type of operation is that a number of secondary electrons are emitted whenever the beam is striking the array, though temporarily greater or lesser amounts of secondaries may appear during writing or reading operations The equilibrium value of secondary electron current at the collector forms a " pedestal " upon which the reading information is superimposed Variations in the fractional collection of such secondary electrons affect the " pedestral " also and consequently positive identification of the type of information stored becomes more difficult. 785,578 By reading the stored information directly at the target structure that is, by reading the signal caused by the secondary electrons leaving the target instead of those arriving at fflhe collector, the problem of collector efficiency and the variations in fractional amounts of secondary electrons are obviated Further, this not only eliminates shading almost entirtly but increases the magnitude of the output signal as well However, it is also most desirable to apply the writing signal directly to the target assembly and thus in considering obtaining the reading signal from the target assembly directly, it must be remembered that there are two signals that differ by at least three orders of magnitude This means that an amplifier connected to the target assembly for the purpose of amplifying reading signals must not be badly jammed by the considerably larger writing signals. It has been proposed to apply the input signal to the barrier grid directly and take the output signal from the back plate of the target assembly, but with such an arrangement the writing and reading, i e, the input and output circuits, are not eftectively isolated. In accordance with one aspect of the invention there is provided an electron discharge device comprising a back plate, a dielectric target in contact with the back plate, an electrode positioned on the other side of said dielectric target to said back plate an electron gun for projecting a beam of electrons through said electrode and against said dielectric target, and means including said electron gun for storing information on said dielectric target, said last mentioned means further including a coaxial line having its inner and outer conductors

individually connected to said back plate and said electrodeIn accordance with another aspect of the invention there is provided an electron discharge device comprising a back plate, a dielectric target mounted on said back plate, a shielding member encompassing said back plate and dielectric target, an electron gun for projecting a stream of electrons against said dielectric 'target, and imeans including saidi electron gun for applying signals to said back plate to store information on said dielectric target and for receiving information from said dielectric target, said last mentioned means including a first conductor connected to said back plate and a second conductor connected to said shielding member, said conductors together defining a coiled portion. In accordance with a further aspect of the invention there is provided an electron discharge device comprising a back plate, a dielectric target in contact with said back plate, an electrode positioned on the other side of said dielectric target to said back plate, an electron gun for projecting a stream of electrons through said electrode and against said dielectric target and means including said electron gun for storing information on said dielectric target and for receiving stored information from said dielectric target, said lastmentioned means including a first conductor connected to said back plate, a second con 70 ductor adjacent said first conductor so as to be electromagnetically coupled thereto and connected to said electrode a source of writing sgnails connected between said inner and outer conductors, and output means coupled 75 to said conductors for receiving an output signal on flow of current in only one direction in said conductors but no output signal on flow of current in opposite directions in said conductors 80 In accordance with a still further aspect of the invention there is provided an electron discharge device comprising a back plate, a dielectric target in contact with said back plate, a shielding member encompassing said back 85 plate and said dielectric target, an electron gun for projecting a stream of electrons against said target, and means including said electron gun for storing information on said target and for receiving information from said target, sa:,i 9 go last-mentioned means including a first conductor connected to said back plate, a second conductor electromagnetically coupled to said first condiuctor and connected to said shielding memoer, a source of writing signals connected 95 between said conductors and an output circuit, the arrangement being such that an output signal is prevented from being applied to said output circuit on flow of writing current in both said conductors 100 In one specific embodiment oi the invention the writing signal is applied directly to the back plate portion of the target assembly, as is preferred, and the reading signal is taken directly from the target

assembly as a whole 105 In this specific embodiment, a coaxial line is connected through the envelope of the tube so that its inner conductor is connected to the back plate and its outer conductor is connected to a shielding member encompassing the 110 target assembly, the barrier grid being supported by the shielding member so that the outer conductor is in effect connected to the barrier grid. The coaxial line has a portion wound as an 115 inductor with the two conductors having essentially equal inductances and a mutual inductance between the two conductors equal to the self inductance of either The input or writing signal is then applied between these 120 two conductors The charging cur-ent requisite for the capacitance between the barrier grid and the back plate flows to the target along the inner conductor and returns along the outer conductor so that the two currents flow 125 ing in the two conductors effectively cancel each other out in the coiled portion and induce no voltage across this inductance However, when the information is being read, the surface of the dielectric is being charged or dis 130 785,578 charged through capacitances to both the barrier grid and back plate simultaneously so that current flows in both conductors of the line in the same direction This current produces an output signal voltage across the coiled portion of the coaxial line which can be detected and uitilized by an output circuit. The storage tube may be of the barrier-grid type, described above, or may be of the dielectric-island type, disclosed in our Patent Specification No 701,010 In adielectric-island tube a plurality of distinct small dielectric regions or islands are mounted on a back plate In embodiments of this invention utilizing such devices, the charging currents are the same as discussed above However, here the condenser being discharged on reading of the stored information is substantially solely between the dielectric and the back plate so that the current flows almost solely in the inner conductor of the coaxial line. The reading signal may be detected directly across the coiled portion of the coaxial line, as by an amplifier connected thereto, or may be detected by an amplifier connected to a transformer winding inductively coupled to the coiled portion Further the writing signal is substantially prevented from appearing across the coiled portion of the output line by completely shielding the back plate and dielectric members of the target assembly, as by having the target assembly effectively encompassed by the outer conductor of the coaxial line and specifically by a shielding member connected to the outer conductor and to which the barrier grid or field equalizing gid is attached. In this manner, extraneous capacitances between target elements and ground or collector, which may be at ground potential, are reduced or

inhibited thereby eliminating the charging current to these capacitances, which current would not be equally balanced in the two conductors of the coaxial line. A complete understanding of this invention may be gained from consideration of the following detailed description and the accompanying drawing, in which:Fig 1 is a diagrammatic representation of one specific illustrative embodiment of this invention; Fig 2 is a simplified circuit schematic for the reading and writing circuits of the embodiment of Fig 1; Fig 3 is a chart of currents and voltages for various conditions during the operation of the embodiment of Fig 1; and Fig 4 is a diagrammatic representation of another specific illustrative embodiment of this invention utilizing a dielectric island storage tube, only the target portion of the tube being shown. Referring now to the drawing, Fig 1 depicts an illustrative embodiment of this invention utilizing a barrier grid storage tube 10 As known in the art, the tube 10 may advantageously comprise within an evacuated envelope, such as glass, an electron gun including a cathode 11, heater 12, and accelerating and focussing electrodes 13, 14, and 15, defining an electron lens, deflection plates 16 and 17, a 70 collector electrode 18, a shield 19, and a target assembly 20 The target assembly 20 includes a back plate 22, dielectric sheet 23 and a barrier grid 24, positioned directly in front of the dielectric sheet 23 The back plate 22 and 75 dielectric sheet 23 are enclosed within a shielding member 26 to which the barrier grid is attached. In storage tubes of this kind, information is stored by an electrostatic charge on a discrete 80 zone or area of the surface of the dielectric 23. To place such a negative charge on the surface, the electron beam is turned on while the back plate is temporarily raised to a positive potential This temporarily raises the potential 85 of the front face of the dielectric through capacitive action The electron beam then charges this surface with negative electrons sufficiently to drop its potential to that of the barrier grid which is the equilibrium potential During the 90 charging operation, the secondary emission electrons from the dielectric return to it and cannot escape When the beam is turned elsewhere and the back plate potential returned to normal, the charge remains, leaving the di 95 electric surface at a negative potential. In this embodiment of the invention the writing circuit, which applies the positive writing potential to the back plate during the storage operation just described, comprises a 100 coaxial line 28 having its inner conductor 29 connected to the back plate 22 and its outer conductor 30 connected to the shielding member 26 and thus to the barrier grid 24 The coaxial line 28 has a portion 32 wound as an 105

inductor with the two conductors 29 and 30 having equal inductances at this portion and a mutual inductance between them equal to the self-inductance of either one A source 33 of input writing Signals is connected between 110 the inner and outer conductors 29 and 30 of the coaxial line 28. When a writing signal is applied by the source 33, the current flows along the inner conductor 29 to charge the internal capacitance 115 and returns via the outer conductor The coiled portion of the coaxial line acts as, a non-inductive winding, and, ideally, in the absence of beam current no voltage should appear between the 'barrier grid 24 and 120 ground. The information thus stored in this spot or zone on the surface of the dielectric 23 is subsequently read by returning the electron beam to this spot The beam in striking the dielec 125 tric releases more secondary electrons than there are primary electrons striking it and these are repelled from the surface, causing the potential to rise to that of the barrier grid. The potential will not become more positive 130 785,578 than the barrier grid through this type of action because the secondary electrons in that case would return to the surface and fail to excape At equilibrium, the dielectric surface releases as many electrons as arrive and remains at the barrier grid potential. It is thus apparent that when the information is being read out, the surface of the dielectric is being discharged through capacitances both to the barrier grid and the back plate simultaneously Accordingly, current will flow in both the inner conductor 29 and the outer conductor 30, in the same direction. These currents produce a signal voltage across the coiled portion 32 of the coaxial line 28 which can be read by an output circuit In this specific embodiment, a resistance 34 is connected in shunt across the coiled portion 32 and an output amplifier 35 is connected across the resistance 34 and the coiled portion 32. Thus, application of the writing signal alone to the back plate ideally will induce no signal into the reading amplifier However, the electron beam will affect the reading amplifier by applying current to the storage target as a whole The net current to the target will be the difference betwen the impinging beam current and the escaping secondary electron current Any change in this net current will cause a signal to appear and be amplified Whenever the dielectric surface is being charged or discharged, whether in reading or writing, there will be a deficiency or excess of secondary electron current escaping from the target; the detection and interpretation of these current changes constitutes the reading operation. A schematic diagram of the reading and writing circuits of the

embodiment of Fig 1 is shown in Fig 2 In this schematic diagram each conductor of the coiled portion 32 has an inductance L and a mutual inductance M, advantageously equal to L Inner conductor 29 connects one inductance to the back plate, which is represented by the point 36, and outer conductor 30 connects the other inductance to the barrier grid, which is represented by the point 37 Capacitance CQ, which is the barrier grid to back plate capacitance, is connected between points 36 and 37 C 2 is the barrier grid to ground capacitance, which is relatively large, and C is the back plate to ground capacitance, which is very small due to the shielding action of the shielding member 26 and the construction of the target assembly R is the equivalent resistance of the outer conductor of the coaxial line 28 and is also very small. Connected between the two inductors is the writing signal source 33 The output amplifier 35 is connected across the load resistor 34 between the barrier grid and ground During the charging of the capacitor C, ideally current flows from the source 33 through the input inductor L to the capacitor and then all the current returns to the source 33 through inductor L; as mentioned below, not all the current does return and there is a slight unbalance of current in the two inductors. When the beam returns to the charged spot 70 on the dielectric to read out the information stored at that spot, the charge on the dielectric is removed and current flows to ground through both the input and output conductors of the coaxial line We can therefore consider 75 that there is a current generator 40 connected to a point 43 representing the dielectric surface which is connected by a first capacitance 41, representing the dielectric surface back plate capacitance, to the back plate and by a 80 second capacitance 42, representing the dielectric surface to barrier grid capacitance, to the barrier grid The reading signal source is thus an assumed source of current that is actually the difference between the ptimary 85 and secondary electron currents at the dielectric surface As this source and its current path are not actually present, but only assumed, the source has been indicated as connected in the circuit by dotted lines 90 The coiled portion 32 may advantageously be attained by coiling a coaxial cable, using the outer and inner conductors as the two selt inductances of an air core coil However, as depicted in Fig 2, a magnetic core may also 95 be employed rhus in one specific embodiment the coiled portion 32 comprises a wire positioned within a copper tubing wound on a ferrite ferromagnetic core. From the above discussion it is apparent 100 that, when the beam is turned on suddenly at a particular spot on the dielectric 23, there are four possible conditions to consider These conditions are: Case 1:

No charge previously stored and 105 no writing voltage applied; Case 2: No charge previously stored and writing voltage applied; Case 3: Negative charge previously stored and no writing voltage applied; and 110 Case 4: Negative charge previously stored and writing voltage applied. In Fig 3 the character of the current to and from the storage aw ay for each of these cases is shown as a function of time for a pulse 115 of sufficient duration to achieve equilibrium. Also shown are the forms of the voltage pulses generated in the reading circuit In Case 1 only the equilibrium number of secondary electrons leave the surface In Case 2 writing 120 of information on the spot is to occur and there is a temporary deficiency in the number of secondary electrons while the charging operation takes place with a gradual return to the equilibrium value In Case 3 reading of 125 the information previously stored is to occur and an excess number of secondary electrons is produced while the surface is discharged, followed by a gradual return to normal There is also a net current which, as described above, 130 785,578 flows inductively in the coiled portion 32 thereby inducing the output signal voltage In Case 4 the current is at an equilibrium value as in Case 1 because the positive writing pulse alone should return the negatively charged surface to the potential of the barrier grid. The writing signals applied to the target array are of the order of several tens of volts while the reading signals received by the amplifier 35 are of the order of a few millivolts; the reading signals may then of course be amplified to any desired level In the arrangement described, the application of the very large writing signals does not interfere with the operation of the sensitive amplifier connected to the reading circuit Ideally, as discussed above, there should be no signal at all across the coiled portion 32 on application of the writing signal However, in effect a very small signal is induced due to unbalance in the currents flowing in the inner and outer conductors This unbalance is, in part, caused by other capacitances within the tube It is therefore desirable that the back plate and dielectric be substantially entirely shielded from the rest of the tube Accordingly, in the embodiment of the invention depicted in Fig. 1, the shield member 26, which is an extension of the outer conductor 30, completely encompasses these elements. However, there is a very small direct capacitance between the back plate and the other elements in the tube, specifically the shield 19 and collector 18, through the holes in the barrier grid The sheld 19 is advantageously grounded and the collector 18 may be connected directly to ground, as by being connected to the shield 19, or be

connected to ground through a resistance, as shown in Fig 1 This capacitance can be considered, therefore, as a back plate-to-ground capacitance, and is the capacitance C, in Fig 2. Accordingly, not quite all the charging current due to a writing signal in the inner conductor 29 returns through the outer conductor 30; some very small fraction appears as displacement current througi the holes in the barrier grid to ground A; second effect which prevents the perfect current balance desired is caused by the finite resistance of the outer conductor of the line The charging current will therefore induce a slight voltage between the barrier grid and ground This voltage, however, can be kept quite small, well below the magnitude of the reading output signals, so that discrimination between the two types of induced signals is not difficult. The resistance of the outer conductor 30 is shown as resistor R in the schematic diagram of Fig 2 To reduce the value of this resistance, it may be desirable to employ a hollow copper tubing, having a relatively thick wall, as the outer conductor 30. If it is desired further to eliminate the small residual error signal due to the writing signal applied to the target assembly, various types of cancellation schemes can be utilized One such scheme is indicated in Fig 2 wherein a cancelling pulse generator 45 is operated by the writing pulse source 33 to apply a cancel 70 ling pulse of proper sign and magnitude. directly to the reading amplifier 35, as directly across the load resistor 34 to cancel out the residual error signal appearing at that resistor due to the imbalance of current flow in the 75 two conductors of the coaxial line. In Fig 4 there is shown another specific illustrative embodiment of this invention wherein the storage tube comprises a dielectric island tube of the type disclosed in our said 80 Patent Specification No 701,010 In the embodiment of Fig 4, the target array comprises a back plate 50 on the front surface of which are located small spots or islands 51 of dielectric material A field equalizing grid 52 85 is positioned in front of dielectric islands 51 and between it and the remainder of the tube, which may be as depicted in Fig 1; grid 52 is supported by the shield member 26 encompassing the target array 90 In this specific embodiment the output amplifier 35 is not directly connected across the coiled portion 32 but is coupled thereto by an inductive winding 55, whereby transformer coupling is attained with an increase 95 in signal strength over the direct coupling method of Fig 1.

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* GB785579 (A)

Description: GB785579 (A) ? 1957-10-30

Device for providing reproducible mechanical motions

Description of GB785579 (A)

A high quality text as facsimile in your desired language may be available amongst the following family members:

US2867701 (A) US2867701 (A) less Translate this text into Tooltip

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The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

PATENT SPECIFICATION 785 t 579 Date of Application and filing Complete Specification: Feb 6, 1956. No 3607156. D Application made in United States of America on Feb 15, 1955. Complete Specification Published: Oct 30, 1957. Index at icceptance:-Classes 38 ( 5), Bl E, B 2 (A 5 A 1: A 9 X C 6 C 2); and 108 ( 3), 58 M 2 A. International Classification:-FO 6 f H Olh. COMPLETE Si PECIFICATION Device for providing Reproducible Mechanical Motions We, CLEVITE CORPORATION, a corporation organized under the

laws of the State of Ohio,

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* GB785580 (A)

Description: GB785580 (A) ? 1957-10-30

Improvements in and relating to screw connection members with wire coilthreads

Description of GB785580 (A)

A high quality text as facsimile in your desired language may be available amongst the following family members:

DE1072844 (B) FR1146195 (A) US2780265 (A) DE1072844 (B) FR1146195 (A) US2780265 (A) less Translate this text into Tooltip

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The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

PATENT SPECIFICATION 785580 Date of Application and filing Complete Specification: Feb 7, 1956. No 3739/56. B E A D 'Application made in United States of America on Feb 28, 1955. Complete Specification Published: Oct 30, 1957.

Index at acceptance:-Class 89 ( 1), A( 1 A: 2 83: 6). International Classification:-FO 6 b. COMPLETE SPECIFICATION Improvements in and relating to Screw Connection Members with Wire Coil Threads We, HE Li-COIL CORPORATION of Shelter Rock Lane, Danbury, Connecticut, United States of America, a corporation duly organizedi under the laws of the State of Delaware, j' United States of America, do hereby declare the invention, for which we pray, that a patent may lbe granted to us, and the method by which it is to 'be performed, to be particularly described in and by the following statement: - This invention is concerned with improvements in and relating to screw connection members, wherein the member consists of a body to which a wire coil is held so as to provide the body with a screw thread for lengagement by a mating threaded member. A principal object of the invention is the production of such a screw connection member in which the 'body is of ductile material and more especially of thermo-plastic such as can be die moulded, and in which the coil is applied and secured to the body as a final operation to form an internal thread in a hole which-can 'be through or blind or to form an external thread land wherein such threads can be made self-locking if so desired. It has, already been proposed: to provide a nut barrel of a metallic material with a wire coil thread of which at least a complete itop convolution projects above the barrel, with convolution is then deformed in order to secure the coil from being unscrewed from the barrel. However, besides the difficulty of preventing undesirable movement of the coil in the barrel in this form of construction', the method is not applicable where the nut barrel or other screw thread member is of a softer material, in which case it requires, as an additional operation, the threading of the member itself to which the coil is to be applied In another well-known constructional form, a nut is made by first preparing a cylindrical barrel with a lower inner flange which is stood the lower end of a wire coil to form the thread The top rim of the barrel is then turned over inwardly in such a way that the coil is left lPrice 3 s 6 d l pace 4 S a certain freedom to move axially within the barrel Such movability is however particularly objectionable in nuts made from a plastic ' in which it is a frequent cause of failure Furthermore, this known form' of nut requires a coil of special cross-section wire, whereas it is desirable to be able to use the standard type of insert in which the coil forms an inner and outer thread It is also to be noted that none of the well known methods of construction are adapted to provide an external hard screw thread on a body of ductile material.

In a screw connection member in accordance with the present invention designed to satisfy these various requirements, the body of ductile material has a surface originally unthreaded and either cylindrical throughout or partly or wholly tapering, to which the coil, which is shorter than this surface and has inner and outer screw thread parts, is coaxially applied so as to engage said body surface with one of said screw thread parts throughout the length of the coil, said ductile material being compressed and thereby caused to flow about one of the screw thread parts of 'the convolution at one end at least of the coil, whilst leaving the screw thread part of the latter opposite that which engages said 'body surface free throughout at least the major length of the coil to receive the mating member The compressed ductile material may be thus caused to cover the one screw thread part of said end convolution and to project also between at least that convolution and) the next adjacent one Where the body surface referred to is the wall of -a through hole in the body, the coil may have an outer diameter to fit within said hole, and may be inserted so as to be spaced inwardly from the ends of the latter, the compressed ductile material being caused to flow about the outer screw thread parts of the convolution or convolutions at both ends of the coil In such a case one end of said' hole and' the corresponding end of the coil may be reduced in diameter and the material be caused to flow about the outer screw thread; part of the reduced end convolution or convolutions. Where the body surface referred to is the wall of a blind' hole, this may have a raised bottom portion of a smaller diameter than the hole and the coil may have an outer diameter to fit within said hole, and be inserted to bear with one of its ends on the bottom of the latter between said raised portion and, said wall and with its other end spaced inwardly from the open end of the hole, the ductile material of this raised bottom portion being compressed and, thereby caused to flow about the inner screw thread part of the lowermost convolution or convolutions of the coil and the ductile material adjacent said open end, of the hole also compressed and thereby caused to flow about the outer screw thread part of the topmost convolution of convolutions In this case said hole may taper towards its bottom' and' the coil be tapered correspondingly. Alternatively the body surface referred to may be the outer wall of a projection from a shoulder of the body and the coil may have an inner diameter to fit over this surface and be shorter than said projection and positioned on the bottom with one end bearing against said shoulder, the projection being compressed to cause the ductile material at its free end to flow about the inner screw thread part of the adjacent end convolution or convolutions of the coil.

The invention also provides methods of forming screw connection members as thus defined by use of suitable tools as hereinafter set forth. The invention will now be further described with reference to the accompanying drawings, which show several typical embodiments thereof by way of example In these drawings: Figure 1 is a cross-section of a first embodiment in which the ductile body has a cylinrical through hole on whose axis the section is, taken; Figure 2 is a diagrammatic view, partly in axial cross-section, of the tools used for securing the wire coil within the 'hole of this first embodiment; Figure 3 is a view of the same embodiment, as seen in Figure 1, but with the coil in elevation and also showing the operative parts of the tools seen in Figure 2 applied in their final relative positions. Figure 4 is a cross-section, again similar to that of Figure 1, of a second embodiment in which the ductile body has a cylindrical blind hole, Figures 4 a, 4 b and, 4 c showing a series of body blanks also in cross-section for this embodiment, which differs as regards the varying form which the raised body portion in the 'bottom of 'the 'hole may take initially; Figure 5 ' is a cross-sectional view showing the tools used for producing this second embodiment applied -in their final relative positions; Figure 6 is a similar view to Figure 3 of a third embodiment, in which the coil within 70 the through hole is tapered to form a selflocking thread and showing the modification of the tools which this involves; Figure 7 is a similar cross-section of a fourth embodiment with a blind hole which 75 is tapered and a correspondingly tapering coil, again for the purpose of making the thread self-locking and showing the required' modification of the tools, in this case those seen in Figure 5; whilst 80 Figure 8 is a similar cross-section of a fifth embodiment, in which the coil is applied externally onto a projection of the ductile body and once again showing appropriate tools itpplied in their final positions 85 Referring firstly to Figure 1, the body portion 10 'here shown is formed with a hole 11 having a cylindrical inner surface wall 12 originally extending throughout the length of the hole to the open ends 13 and 14 thereof 90 with a uniform diameter, into which hole a wire coil 15 of corresponding outer diameter is inserted The wire of which this coil consists is of such section as to form outer and inner screw-thread parts, denoted 16 and'17 95 respectively The wire may thus be of diamond-shaped section as shown or of any other suitable cross-section The coil' is somewhat shorter in length than the hole 11, so that its ends are spaced inwardly from the 100 respective open' ends 13 ' and 14 of the latter, the faces 18 and 19 of the extremities of the wire preferably lying in planes parallel to the axis a-a of the hole In zones adjacent said open ends of the hole, the ductile

material 105 of the body is then compressed in the axial direction to form annular grooves 20 and; 21 and to cause the material which is thus displaced to flow at 22 and 23 around the end convolutions and over at least part of the end 110 faces 18 and 19 of the coil wire However, the displacement of the material is such that the inner thread' parts 1 7 are not affected and can therefore form the internal thread for the mating member The material at 22 and 23 115 serves both to prevent any axial movement of the coil and also by engagement of said faces 18 and, 19 to prevent the coil from turning. In order to apply the coil to the body, the tools shown in Figures 2 and 3 may be used, 120 comprising an upper stake 30 and a lower stake 31 Both these stakes have annular end rims 32 and 33 with inner conical faces 34 and 35, by which rims the aforementioned grooves 20 and 21 are produced They also 125 have axial bores 36 and 37 in which compressor members 38 and 3 9 respectively are capable of limited longitudinal movement, the member 38 bearing against a spring 49 at the bottom of the bore 36 This spring is heavy 130 785,5,80 stake 60 and is axially movable in the upper stake 6 '5 against a spring 66 corresponding to spring 49, the lower face 6 '7 of this' sleeve being formed helically to engage the top of the coil as described in connection with compressor members 38 ' and 39 Similarly the upper stake has a lower rim 688 'corresponding with those 32 and, 331 of stakes 30 and 31. The raised bottom portion may originally have any one of a variety, of suitable forms of which some examples are shown in Figures 4 a, 4 b and 4 c Thus in Figure 4 a the portion 53 a of the hole 51 is approximately cylindrical with a rather 'deep indentation 62 a; and in Figure 4 'b the portion 53 b is somewhat tapered and has a shallow dent '62 b; whilst in Figure 4 c the portion 53 c is' dome-shaped without an indentation It will be understood that the stake end '61 requires to be so formed in correspondence with these shapes as to urge the material of said portion outwardly and around the inner thread part of the lower coil end, as shown in Figures 4 and 5. If a locking effect is desired, one end of the coil, approximately as much as one convolution, may be reduced in diameter Figure 6 shows such a locking coil 70 with an end convolution 71 reduced in this way, secured within the through hole 72 of the body 73 and adapted for engagement with a bolt (not shown,) screwed in from the opposite end of the coil to said, reduced convolution For thus securing this form of coil in the hole, tools are applied comprising stakes 74 and 75 similar to those 30 and 31 of Figure 2 In this case the upper compressor 7 '6 is however of somewhat smaller diameter than the lower one 77 to correspond with the reduction in size of convolution i 71 Interiorly of these compressors, a guide 7 '8 isi provided which has a

major diameter section 79 to fit the interior of the main cylindrical part of the coil and a tapering section 80 to fit within convolution 71 Figure '6 shows besides how the ductile material is caused to project between the 'outer thread parts of the end convolution 71 of the coil of at least the next adjacent one In the embodiment of Figure 7, a coil 81 tapering towards its lower end 82 is shown inserted within the hole 83, which is here generally tapered at 84 around the raised bottom portion 8 '5 The lower stake 86 in this case has a conical bottom section '87 corresponding to and for the same purpose as section 63 i in Figure 5, and another more gently tapering section' 8 '8 to correspond with the general taper of the hole. In the Figure 8 construction, the body, 90 has a cylindrical projection 91 from a shoulder 92 thereof and is somewhat longer than the coil 93; placed around said projection The lower end of the coil be'ars against said shoulder, which is therefore preferably made correspondingly helical in form to engage therewith, The coil may be secured to said projection enough to compress the convolutions of the coil, but is adapted then to collapse to an extent dependent on the length of the coil, variations in which are bound to occur in manufacture The compressor members both have helical end faces 40 and 41 shouldered respectively at 42 and 43 for engagement against the inner screw thread' parts of the end convolutions of the coil and the corresponding parts of the end faces 18 and 19 of the wire, thus leaving the outer coil parts free for envelopment by the ductile material The compressor 39 has an axial extension 44 for engagement with the bore 45 of the compressor 318 in order to ensure co-axiality of the parts and to prevent radial collapse of the coil during the staking operation Figure 3 shows' clearly how the tools are applied to the coil 15 after insertion in the hole 11 and how the compressors hold its convolutions close together while the rims 32; and 33 ' cause material of the engaged zones to flow around the end convolutions in the manner already explained, when the stakes 30 and 31 are urged towards one another axially By thus having the one compressor only spring loaded, it is ensured that the force of compression applied to the stakes is transmitted to the ductile material rather than to the 'coil. in the embodiment of Figure 4, in which the body 50 is provided with a blind hole 51, the latter has an inner cylindrical surface wall 52 and a raised bottom portion 53, the original diameter of which is so much less than that of this wail that the coil 54, which is similar to coil 15 of Figure 1, can be inserted with its lower end between said wall and said raised bottom portion The coil is shorter than the hole 51 so that, when thus positioned, its top end 55 ' is spaced inwardly from the epen end 56 of the hole, In the zone adjacent this open end the

ductile body material is caused to flow at 57 around the top convolution of the coil substantially as already described with reference to Figures 1 to 3 ' However, at the other end, tle material of the raised 'bottom portion 53 is urged outwardly after the insertion of the coil so as to be caused to flow at 518 around the inner screw thread part of the lowest coil convolution The securing of the coil can 'be effected by the tools as shown applied thereto in Figure These tools comprise a modified form of lower stake 60 with a reduced end 61, adapted to engage an indentation '62 which is preferably provided on the raised bottom portion 53, and a short conical section 63 ' between this end and the main part of the stake which is of uniform diameter to fit within the coil. When this lower stake is pressed' downwardly together with the upper stake 65, the end 61 deepens, the indentation 62 and the conical section 63 urges the material of the bottom portion 53 outwardly as required A compressor sleeve 64 for the coil surrounds 785,580 by means of a retaining die 94, which is so formed and applied that it encloses at least part of the body together with the coil and the end face 95 of the projection By driving a mandrel or punch 96 through a coaxial bore 97 of said projection, which bore is originally of smaller diameter than said mandrel, the ductile material of the projection is caused, to flow both between the inner thread; parts of the convolutions, as for instance at 98, and simultaneously around the corresponding part of the end convolution at 99. It will of course be understood that the tools shown in Figures 3, 5, 6, 7 and 8 are removed once the coils have been secured in position.

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* GB785581 (A)

Description: GB785581 (A) ? 1957-10-30

Improvements in and relating to resistance welding machines

Description of GB785581 (A)

PATENT SPECIFICATION 785581 Date of Application and filing Complete Specification: Feb 20, 1956. No 5154/56. Application made in Switzerland on Feb 21, 1955. Complete Specification Published: Oct 30, 1957. Index at acceptance:-Class 83 ( 4), R( 2: 4: 1 Q), International Clia i icgtion,3-B 23 k. COMPLETE SPECIFIGATION Improvements in and relating to Resistance Welding Machines We, H A i SCHLATTER A G, a body corporate organised and existing under the laws of Switzerland, of Seestrasse '121, Zollikon, Zurich, Switzerland, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to 'be particularly described in and by the following statement:- In resistance welding machines the work pieces must be kept during the welding operation under high pressure (the so-called welding pressure) by the electrodes For this purpose at least one of the two welding electrodes is made movable, and this electrode is further equipped with a mechanical, pneumatic or hydraulic feed action To enable the work pieces to be conveniently inserted between the electrodes, such feed action must have a considerable length of stroke or travel; but the high welding pressure obviously only requires to be applied (after the work pieces have been loosely gripped) over the last, short part of the feed stroke during which pressure contact is attained and the work pieces become deformed during the welding process Therefore it is usual to resolve the length of this feed stroke into two stages that are performed with different amounts of force or power For instance, if a toggle mechanism is used for the movable electrode, the advance during the second part of the feed stroke is performed with greater force but at a lower speed than the advance during the first part, In present day practice, however, pneumatic drives are used in, order to save space; but with these it was not possible heretofore to perform the last part of the stroke with sufficient force or at a sufficiently low speed; on the contrary, the electrodes were pressed together for performing the welding operation too quickly. The present invention relates to a welding machine w Ith pneumatically operated twostage feed action, the first stage of which (the setting stroke) is performed by direct, pneumatic drive and consequently with low power and relatively high speed, and the second stage of which

(the welding stroke) employs a lprice hydraulic press as an intermediate link, thus obtaining a slow advance motion with great power or pressure The pressure rise takes 50 place very rapidly,, as soon as the electrodes and the work pieces are in positive contact. In the welding machine of the invention the movable electrode is mechanically linked with;a hydraulic ram (henceforth called the 55 "main ramn") This main ram receives the mechanically transmitted pressure of a strokelimited pneumatically operated " auxiliary ramn " which propels the main ram during the first step of the feed action, the " setting 60 stroke " The cylinder of the hydraulic main ram (henceforth called the main cylinder") is, during the first stage of the feed action, in communication through a passageway with a' liquid container from which liquid enters 65 into ithe hydraulic space of the main cylinder during said setting stroke Furthermore, the hydraulic space of the main cylinder is in communication with a "displacement chamber" which is also filled with liquid and 70 wherein is movably arranged a pneumaticallyactuated displacement plunger " Before or at the beginning of the action of this plunger, the aforesaid passageway is closed and thereupon the plunger presses the liquid contained 75 in the displacement chamber into the hydraulic space of the main cylinder thereby actuating the main ram to perform the " welding stroke " The mechanical transmission of the force 80 from the auxiliary ram to the main ram can for instance be effected by 'a system of levers or by a rod secured to the auxiliary ram A particularly compact arrangement is obtained if the smaller bored auxiliary cylinder is 85 arranged in la staggered, axially parallel relation to the main ram and the auxiliary ram connected to a rod passing in airtight manner through the bottom of the auxiliary cylinder in a direction parallel to the axis of the 90 main cylinder and pressing on the main ram in the raised position of the electrode The stroke of the auxiliary ram is most suitably adjusted by a movably adjustable end stop. The passageway through which the main cylinder communicates during the first stage of the feed action with the werking fluid container may be provided with a mechanically, electrically or pneumatically actuated control valve closing before initiation of the second stage of the feed action Most simply however this opening is made in the form of a cylindrical port located in the path of the displacemenit plunger; this displacement plunger then itself closes said port before applying the hydraulic pressure to the main ram. The invention will be fully understood from the following detailed description and the accompanying drawing which shows one embodiment by way of example. Flig 1 represents a diagrammatic vertical section through the clamping electrode head of the machine; Fig 2 depicts a motion diagram of the

movable electrode. The movable electrode 1 in the clamping head shown is moved downwards in the direction of the arrow and forced towards the counter electrode 2 supporting the work pieces 3, with the necessary welding pressure The electrode 1 is held in a chuck 4 to which a current feeder 5 is attached, and a plunger 6 rigid with the chuck is guided in a bush 7 held in a casting 8 which forms a part of the machine housing The upper, reduced part of the plunger 6 carries the aforesaid main ram 9 which slides in a wide, cylindrical bore of the casting 8 The chamber of this main cylinder situated above the main ram 9 is designated 10 and is assumed to be filled with a hydraulic working fluid (e g oil) The cylinder chamber 11 situated below the ram 9 is connected with a compressed air pipe 12. A separate auxiliary cylinder 13 is fitted above the main cylinder 10, 11 and contains the aforesaid auxiliary ram 14 The cylinder space above the auxiliary ram 14 is connected through a pipe 15 and a solenoid operated valve 16 with a compressed air pipe 12 a The lower end of the rod 17 of the auxiliary ram 14 rests on the head of -the plunger 6; the upper end of the rod 17 projects through the cylinder cover 118 and carries a handwheel 19. This handwheel acts in conjunction with an annular shoulder 20 on the cylinder cover 18 as an adjustable limiting stop for the downstroke of the auxiliary ram 14 Shortly before the handwheel 19 makes contact with the annular shoulder 20, it closes a safety contact 21. The chamber 10 of the main cylinder communicates with a lateral cylindrical bore 22 which is closed on the left by a screw plug 23 This bore contains on the right a displacement plunger 24 This displacement plunger 24 is pneumatically actuated by an appreciably larger piston 25 In the rest position shown, the piston 25 is forced to the extreme right by the pressure of a spring 26. The compressed air chamber 27 of the driving piston 25 communicates through a pipe 28 and a solenoid operated valve 29 with the compressed air pipe 12 a. Above the displacement cylinder 22 is an 70 oil tank 30 which is vented through a drilled cap 31 This 'oil tank communicates with the displacement cylinder 22 through a cylinder port 32 located immediately next to the end position of the displacement plunger 24 75 The machine is controlled in known manner by a treadle lever 33 actuating the contacts of the electric control circuits This treadle is shown diagrammatically on the right of Fig. 1 When actuated, the treadle first closes a 80 contact 34 which applies a voltage U to open the valve 16 It next closes a contact 35 which applies a voltage U to open the valve 29 if the safety contact 21 has been closed For the release of the compressed air to allow the

85 return of the ram 14 and the piston 25 each of the two cylinder spaces 13, 27 can be provided with an additional solenoid operated valve In Fig 1, for the sake of simplicity, two vents 36, 3 i 7 are shown fulfilling this pur 90 pose and having such a small size that their presence does not substantially affect the pressure exerted on the rams 14, 25 by the pressure air when the valves 16, 29 are open. The diagram in Fig 2 shows the path " S " 95 of the motion of the electrode 1, against the time C" It is assumed that at the time t, the contact 34 is closed to move the electrode 1 in stage 0-I and remains closed from time t, to t and at the time t the contact 35 100 is closed to move the electrode in the welding stage II-III; and also, that at the time t, after completion of the weld, the contact 35 is opened to move the electrode 1 through stage III-IV and at the time t, the contact 105 34 is again open to return the electrode 1 to the initial position. -In the rest position, the main ram 9 is held in its uppermost position by compressed aii entering through the pipe 112, the collar 4 a 110 on the chuck 4 making contact with the bush 7 Oil originally contained in the upper space of the main cylinder has been forced through the cylinder port 32 back into the oil itank 30 The auxiliary ram 14, relieved 115 of pressure, is in its top position In this posiiion of the electrode 1, the work pieces can conveniently be inserted in the electrode gap and adjusted there. When now, by operating the treadle 33, the 120 contact 34 is closed, the solenoid operated valve 16 is opened and compressed air entering above the auxiliary ram 14 presses this ram downwards; simultaneously, the rod 17 also moves the main ram 9 and the electrode 1 125 downwards in stage O-I Fig 2 This pneumatically effected motion, however, is damped by the braking effect of the narrow passageway 32 through which oil is sucked from the container 30 into the hydraulic space of the 130 i 7,85,581 785,5181 cylinder 10 Said flow of oil however is stopped as soon as the handwheel 19 has made contact with the shoulder 20, thus arresting the motion of the auxiliary ram 14 By suitably adjusting the handwheel 19, it is thus possible to set the stroke " S " of the first feed action stage t 0-t, (Fig 2), to any desired length This length of stroke is suitably so selected that when the electrode 1 is at the end of this portion of its travel, it is about 0.5-1 mm above the work-pieces 3, or just makes contact with them. When, at time t 2, the treadle 33 is further depressed to close the contact 35, the safety i 5 contact 21 in series therewith is already closed and the solenoid operated valve 2,9 consequently opens immediately Consequently, the chamber 27 becomes charged with compressed air which forces the piston 25 against the aotion of the spring 26 to the left This causes the displacement plunger 24 attached

to the piston 25 firstly, to close the cylinder port 32 and next so compress the fluid in the upper space 10 of the main, cylinder Owing to this, the main ram 9; with the plunger 6 and the electrode 1 moves down hard into contact with the workpieces 3 Immediately this contact has taken place, the pressure exerted by the main ram 9 on the electrode 1 rises to a very high value; this is due on the one hand to the air pressure existing in the chamber 27 and acting on the displacement plunger 24, and on the other hand-according to the principle of the hydraulic press-,to the ratio of the crosssectional areas of the displacement plunger 24 and the main ram 9. When the welding operation has been completed, the operator first opens the contact 35, whereupon the valve 29 closes and the spring 2,6 presses the piston 25 against the falling pressure of the exhausting air, again to the right This allows the main ram 9 with the electrode 1 to rise under pressure of air from the pipe 12 until the head of the plunger 6 again makes contact with the rod 17 of the auxiliary ram 14 '(stage III-IV of the feed action, see Fig 2) If the contact 34 is also now opened, the valve 16 closes and' the air pressure above the auxiliary ram 14 sinks to zero, The compressed air entering underneath the main ram 9 from the pipe 12 now raises both rams again until the collar 4 a makes contact with the bush 7 The machine is now ready for the next welding operation. As will be seen, the hydraulic action of the main ram' 9 acts only as an 'intermediate link for obtaining a shock free, very, shont stroke with a high end pressure The actual working fluid for all motions is ordinary compressed air It will further be seen that an exceedingly compact and space saving arrangement lof the mechanism is obtained, the bulk of which can be further reduced by moving the cylinder of the auxiliary ram '14 to the left away from the axis of the main cylinder 10, 11. The return stroke of the piston 25 can, be performed by compressed air instead of by a spring, the air being admitted,to the cylinder space to the left of the piston 25, as soon as the valve 29 closes It is even more suitable 70 to provide a separate return piston for this purpose, in order that the cylinder space to the left of the piston 25 shall always remain free from pressure. In practice it is not always necessary to 75 raise the electrode 1 completely after each welding stroke, It is, for instance, sufficient in the case of so-called' "'spot seam welds" ( stitch welds ") to raise the electrode 1 between welding strokes only by about 1-2 80 mm in 'order to be able to move the work forward in the direction of the seam Contact 34 then remains continuously closed (i e the magnetic valve 16 is continuously open) and the individual (spot) welds are made only by 85 the action of the piston plunger assembly 2,5, 24

controlled by the contact 35, In such case it is possible by suitably adjusting the hand" wheel 19 to set the fixed stroke of the auxiliary ram 14, and, hence the action of the 90 main ram 9 at any desired value. The spot welding electrode shown can, of course, in making seam welds, be replaced by any, convenient, known form of contact roller.

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* GB785582 (A)

Description: GB785582 (A) ? 1957-10-30

Strip aligning device

Description of GB785582 (A)

COMPLETE SPEGIFICATION Strip Aligning Device We, THE GOODVEAR TIRE l & RUBBER COMPANY, a corporation organized under the laws of the State of Ohio, UnitearL States of America, with offices at 1144 East Market Street, Akron, Ohio, United States. of America, do hereby jdecllare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in. and by the following statement: This invention relates to a strip or web aligning apparatus and more particularly to an apparatus for depositing a continuousi length of strip material such as extruded unvulcanized rubber or rubberized fabric on a moving surface in a predetermined position prepara

tory to subsequent operations. thereon. In the manufacture of rubber products, many steps are taken in preparing the component parts that go into the ifinished products. In numerous instances, the material is in strip or web form at some stage of the preparation. The strips ior webs of material are dlifficuLr to handle because of lack of rigidity and the ease with which they may be distorted. As a result, the usual aligning mechanisms will not function satisfactorily in depositing strips of this material on a moving surface because the forces. are applied to the strip in localized areas rather than disitr,ibut!ed over a substantiail portion thereof. A particularly difficult strip to handle is a continuous strip of unvulcanised extruded tread stock for tires as it is not of uniform cross section across its width and due to the nature of the material, the known aligning mechanisms are not applicable for use with unvulcanized rubiber tread stock. The thin edge portions of the tread stock will be distorted when it is drawn over rolls or fed over and under bars to align the strip. It is imperative that the tread be free from distortion when it is applied to the carcass. To prevent such distortion, a substantial; portion of the strip must be moved simultaneously to change the position of the strip. In order to minimize the effects of the tread splice in the finished tire, it has been considereal Desirable to cut or skive the tread to the proper length so that the splice angle in the finished tire is at a substantial angle with the circumference of the tire. This distributes the splice over a substantial portion of the periphery of the tire rather than across the tire at one point. In order to have such a splice, the skive of the tread stock must be made at a substantial angle with the edge of the extruded tread and there it is essential that the edge of the strip of tread stock be accurately positioned with respect to the conveyor belt d the skiving machine.. If not, each cut or skive would not be at the same angle with the edge of the tread) so that the ends would not be parallel and could not be properly joined' upon application to the tire carcass. In some instances, a continuous strip of rubberized fabric is processed on a layeup table or the like where a thin layer of cushion stock is applied to the fabric strip. The layer of cushion stock may be of a width less than that of the fabric so that it is laid on the fabric with a predetermined margin. If the placing of the cushion is

to be accurately. done, it is essential that the fabric strip always be placed on the lay-up table in precisely the same position, otherwise the marginal spacing would not be consistent, Manipulation without distortion of webs of material such as these may be made by moving a relative large portion lof the web at one time In this manner, the forces, are distributed and at any particular point are not sufficient to create harmful distortions. It is therefore an object of this invention to provide an apparatus that will accurately deposit a strip of unvulcanized rubber material or rubbersized fabric on a moving surface in a predetermined position without distortion of the strip. Another object of the invention is to provide a simple and inexpensive apparatus to align a strip of material within close tolerances as it passes from one conveying system to another. A further object of this invention is to provide an alignment device that will funtion accurately in continuous operation. A still further object of the invention is to provide at apparatus that operates in coordination 'with the apparatus that performs the subsequent operations on the strip material. In the drawings: Fig. 1 is a front elevation of an embodiment of the invention showing its position with respect to a skiving machine; Fig. 2 is an end view of the invention; and; Fig. 3 is a plan view. FOT purposes of illustration,- the invention will be described in combination with a tread skiving machine which is well known in the art. In the usual skiving machine operation the extruded tread stock is carried by a conveyor through tanks of water for cooling after it leaves the extruder. Subsequently the strip of stock is transferred then to the conveyor belt of the skiving machine or skiver which carries the strip through the machine under one or more cutting blades which skive the strip into lengths of predetermined size. Since the length of aav travel during cooling is substantial and no attempt is made to position the strip of material accurately, the strip is not transferred at all times to the conveyor of the skiver in a sufficiently accurate and straight line position to be properly skived. These lengths are removed and stored until they are to be applied to the tire carcass during the tire building operation. The numeral 1 represents a skiver or skiving apparatus of the usual construction having a conveyor belt 2 which supports and carries the strip 3 of extruded unvulcanized rubber tread material through the apparatus 1. The revolving knife 4 automatically skives the tread stock 3 at a

predetermined point as it passes through the apparatus as is well known in the art. The belt 2 of the skiver is supported on one end by the pulley. 5 which may be moved relative to the other pulley (not shown) of the skiver so as to provide means to adjust the tension in the belt 2. Adjacent to the skiver 1 the web aligning apparatus 6 of this invention is mounted so that the conveyor belt 7 of the aligning appa ratus 6 is in substantial longitudinal alignment with the belt 2 of the skiver 1. The strip 3 of unvulcanized rubber tread stock enters the aligning apparatus 6 from the cooling tanks '(not shown) and is carried: through the aligning apparatus 6 on the upper reach of the belt 7.. The position of the strip 3 as it is placed on the belt 7 from the cooling tanks is not specifically controlled so that it may vary considerably. The belt 7 iof the aligning apparatus is driven at substantially the same peripheral speed as the belt 2 of the skiver. If desired, a series of idler rolls 8 may be interposed between the skiving apparatus 1 and the aligning apparatus 6 to prevent undue sagging of the strip 3 as it passes between the machines. In order to deposit the unvulcanized rubber strip 3 on ithe belt 2 of the skiving apparatus in: the predetermined position, means are provided to automatically change the relation of the longitudinal axis of the belt 7 of the aligning apparatus with respect to that of the belt 2 of the skiver.. As the belt 7 moves out of alignment, the section of ,the strip 3 on the belt 7 approaches the belt 2 of the skiver at an angle such that the strip 3 will continue to be deposited on the belt 2 at the predetermined position. The dotted lines in Fig. 3 indicate the out of alignment position. Between the aligning apparatus 6 and the skiver 1 a sensing mechanism or detector 9 is positioned so that, as shown, the edge of the strip 3 of material passes through the sensing mechanism. It is to be understood! that if desired the sensing mechanism 9 may be positioned so that other portions of ithe strip will activate it. As the edge of the material moves from the predetermined position the sensing mechanism 9 is activated, which in turn actuates an oil cylinder 10 to move the aligning apparatus 6 so as to keep the edge of the strip of material 3 at the desired position. In order to more fully understand the operation of the aligning apparatus 6 in Figs. 1, 2 and 3 the belt 7 is supported by rolls 11 and 12 to form the conveying system of the aligning apparatus. One means that may be readily used to drive the belt 7 at the same speed as the belt 2 of the skiving apparatus is a chain drive from the shaft on which pulley 5 of the skiver is mounted. The chain 13 passes around a sprocket gear 14 affixed to the shaft of the pulley 5, over the idler 15, around the

sprocket gear 16, then over idlers 17 and 18. A take-up idler sprocket 19, be- tween idlers 17 and 18, retains the proper tension in the chain when the pulley 5 of the skiver is moved in order to adjust the tension of the belt 2 of the shiver. As best seen in Figs. 2 and 3, a base structure 20 includes a top cross member 21 carrying a shaft 22 supported by bearings 23 attached to the cross-member 21. The sprocket gear 16 keyed to the outer end of the shaft 22 is, as previously explained, driven by chain 13 drive extending from the sprocket 14 of the skiver. On the opposite end of shaft 22, a bevel gear 24 is affixed and engages a ring gear 25 rotatably attached to the top crossmember 21. Diametrically opposite the normal position of 'bevel gear 24 on the ring gear 25, a second bevel gear 27 engages the ring gear 25. This bevel gear 27 is attached to shaft 28 supported on bearings 29 attached to the framework 30.. As shown, the ring gear 25' allso is supported for free rotation on thrust bearing 31 on a cross-member of framework 30. The attachment of the ring gear 25 to both the Ibase 20 and framework 30 allows limited relative movement between them. The rolls 11 and 12. are carried on shafts 32 and 33 respectively supported in bearings 34 attached to the framework 30. On the outer end of the shaft 28, a gear is attached thereto which engages gear attached to the shaft 32 of the roll 11. Since the framework 301 is pivotally attached to the base 20 through the ring gear 25, it may be moved independently of 'the base 20 without interrupting the drive of the belt 7. The vertical center line iof the rinlg gear 25 is the axis about which the framework 30 pivots. It is apparent that by the proper selection of sprocket sizes for the sprockets 14 and 16, the belt 7 on the aligning apparatus may be driven at the same speed as belt 2 of the shiver. As the longitudinal axis of the 'belt 7 is moved out of alignment with the longitudinal axis of the belt 2 lof the skiver, position of the bevel gear 27 changes on the ring gear 25 ibut the bevel gear 2.7 lis stilll driven thereby. The shaft 22 remains fixed with respect to the abase 20 and top frame member 21, but the position of the shaft 28 and the framework 30 with its component parts changes. So that the framework 30 which supports the rolls 11. and 12 map reaidlilly move about the pivot ,(indicated iby broken lines in Figs. 1. and 2) the framework 30 is supported on rollers 37 carried by vertical members 38 and 39 of the framework 30 Ways for the roller 37 in the form shown, are plates 40 attached to the base 20.. Iodine form' of sensing device or position detector that has been found very satisfactory for the strip aligning apparatus is shown al- though it is to be understood that many types of such devices such as photo-electric cells, vacuum operated, other electrical systems, etc.

are available for such uses. The particular device illustrated consists. lof a low pressure air stream 4k1 (see 'Fig. 1) passing over the edge of the strip of material. As the flow of air is altered by the change in position of the edge of the material, the oil cylinder 10 is. activated to return the strip edge to the desired position. One form of such a device is shown in the United States patent No. 2,539,131, issued to D., T. iGundersen. This particular device that has. been found to be very; satisfactory has a relatively fiat elongated nozzle opening 42 positioned transverse to the edge of the material with ,the edge ibeing substantially at the center of the nozzle opening in the desires position. When the edge of the material moves to one side or the other of the nozzle opening 42, the change in pressure in the receiver mechanism of the apparatus actuates the oil cylinder 10 to cause the connecting red 43 of the cylinder to be extended or retracted. The connecting rod 43 is pivotally attached at 44 to the framework 30. Con- sequently, as the connecting rod 43 is retracted or extended the framework 30 is rotated about the pivot point causing the longitudinal axis of the belt 7 to move out of alignment with the longitudinal axis of the skiver belt 2 and move the edge of the strip back to the center of the nozzle opening 42.. At this point, the sensing device 9 returns the cylinder 10 to its normal position. Subsequently any change in the position of the strip edge causes the aligning device to activate the oil cylinder to keep the edge of the material in the predetermined position.. As the framework 30 moves, the portion of the strip 3 that lies on the belt 7 is moved as a unit rather than at a localized point or points. This prevents undue distortion in portions lof the strip with the result that the strip is placed undisltor,ted on the Ibelt of the skiver in the proper position for accurate skiving. Although the aligning device has been described in 'combination with a tread skiving apparatus, it may be used in combina- tion with any apparatus which requires that a moving web of material 'be positioned thereon in a fixed position. In each instance, it is desirable that the device is positioned immediately ahead of the moving surface of the apparatus. While certain. representative embodiments and details have 'been shown for the purpose of illustrating the invention it will Ibe app a- rent to those skilled in this art that various changes and modifications may ibe made therein without departing from the scope of the invention, as defined, in the appended claims. What we claim is: - 1. A strip aligning device for depositing a continuously moving web of material in a predetermined lateral position on a moving surface, including an endless belt mounted adjacent one end of the moving

surface for swinging movement in a plane parallel to such surface, adapted to support the web of material and feed it onto the moving surface, means to drive the belt at substantially the same speed as the moving surface, a sensing device activated when the edge of the web moves out of the predetermined position to actuate means adapted ito control the swing of the belt to guide the web in the predeter- mined position on the moving surface. 2. A device according to claim 1, wherein the sensing device is mounted between the moving surface and the belt 3. A device according to claim 1 or 2, wherein the belt travels over two or more rolls rotatably mounted on a framework mounted for free rotation about a vertical axis, the longitudinal axis of the belt normally being in alignment with the longitudinal axis