* GB784773 (A)

Description: GB784773 (A) ? 1957-10-16

Milling machine for cylindrical stereotype platens

Description of GB784773 (A)

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PATENT SPECIFIC Ar ION 784,773 @ v Date of Application and filing Complete Specification M Sarch 7, 1956. No 7177/56. Application made in Sweden on March 15, 1955. Complete Specification Published: October 16, 1957. Index at acceptance:-Class 83 ( 3), K 3 (H 9: J: L 3: L 5: L 6), I 7 CBX: Cl: H: Q 1: Q 2). International Cia:sification:-B 23 c. COMPLETE SPECIFICATION Milling Machine for Cylindrical Stereotype Platens We, J DAHL & SON AKTIEBOLAG, of Adolf Fredriks Torg 5, Stockholm, in the Kingdom of Sweden, a Swedish Company, 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: - The present invention relates to a machine for milling cylindrical stereotype platens by milling cutter m-eans which are displaced substantially in a radial direction toward a rotatable and axially movable cylinder on which platens to be milled are arranged. Milling machines for cylindrical stereotype platens are known, wherein the stereotype platen is arranged on a cylinder which is rotatably mounted on a shaft The whole cylinder with its mounting is displaceable in the axial direction on a slide outside the cylinder, and is rotated by means of a gear pinion meshing with a gear wheel at one end of the cylinder By reason of the fact that the means for the rotation and longitudinal displacement of the cylinder are arranged outside the cylinder, these means are exposed to swarf and impurities which may disturb the precise functioning of the machine Particularly, where it is desired to mill a number of platens at the same time, as is the case, for instance, in a printing establishment having a number of presses operating in parallel multi-colour printing, the mounting of a corresponding long cylinder cannot be constructed with the accuracy required in such a case. In the milling machine according to the invention, said drawbacks are avoided in that the mounting and driving means for the rotation and axial movement of the cylinder are enclosed within the latter. The invention will be clearly understood from the following detailed description aided by the accompanying, partly diagrammatic drawings which show, by way of ex(Price 3 s 6 d) ample, an eight-spindle milling machine. Fig 1 is a front elevation, partly in vertical section. Fig 2 is an end view of the machine. Fig 3 is a plan of the machine 50 Fig 4 shows a mounting means for the cylinder. Fig 5 shows the mechanism for effecting rotary movement of the cylinder. Fig 6 shows the mechanism for effecting 55 axial movement of the cylinder. The milling mach'ne is erected on a base plate 1 with end walls 2, 2, which are united by a rear wall 3 In a pair of floor-stands 4, 4 arranged on the base plate outside the 60 end walls 2, a substantially cylindrical supporting shaft 5 is immovably held, this shape having reduced plane surfaces 6 bearing on corresponding planes of the floorstands 4 Keeps 7 7 maintain the support 65 ing shaft 5 pressed against the floor-stand planes The supporting shaft 5 extends along the front side of the machine and carries a relatively thinwalled hollow cylinder 8 concentrically mounted on the support 70 ing shaft Arranged on the surface of the cylinder 8 are rigid steps 9, against

which cylindrically curved stereotype platens 10 are adapted to bear The machine shown in the drawing is intended for the milling of up 75 to eight platens at the same time, which are placed, four of them in a row along the cylinder 8 and four others diametrically opposite the first-mentioned platens For each platen 10 there is provided a milling spindle 80 11 displaceable radially toward the cylinder 8, four spindles being mounted on a beam 12 adapted to be raised and lowered and located above the cylinder 8, and four spindles being arranged on a beam 12 adapted 85 to be raised and lowered and located below the cylinder The spindles 11 are driven in pairs by means of belt transmissions 14 from electric motors 15 secured in the rear wall 3, the milling machine described being 90 784,773 equipped with two motors in the upper part and with two motors in the lower part thereof The radial setting of the milling spindles 11 is effected by means of a treadle 16 arranged along the front side of the machine and acting at the same time over a lever system on the upper and the lower rows of spindles 11 The treadle, which is operated from the front side of the machine and which is preferably lockable in a depressed position, has each end rigidly connected to a lever 16 ', which is pivoted in bearing brackets 16 " at both ends of the rear wall 3 The two milling spindle beams 12 and 13 are guided in a vertical direction in guide ways 17, 17 in the end walls 2, 2 and are operated by means of levers 18 and 19 respectively pivoted in the upper and the lower parts of the end walls 2 2 The two lower single-armed levers 19 are pivoted at 20 and are each provided at a point 21 between the ends thereof with a lifting roller 22 in engagement with the lower spindle beam 13 The two upper double-armed levers 18 are pivoted at 23 and are each provided with a lifting roller 24 in engagement with the upper spindle beam 12 The rear ends of the levers 18, 19 at each end of the machine are pivotally connected by means of a link rod 25, and the lever 19 is connected at 26 ', inside its fulcrum 26 with the link rod 25, with one end of a shorter link rod 27, the other end of which is pivotally connected at 27 ' with the treadle 16 Here, the leverage is chosen so that the upper beam 12 will have imparted to it a movement which is approximately twice as great as that imparted to the lower beam 13 Thus, if the upper beam 12 has a movement of displacement of 16 mm, the lower beam 13 has a displacement of 8 mm Hereby balancing of the beams is obtained when the treadle 16 is operated A compression spring 27 is also provided for this purpose and is clamped on the long link rod 25 between an abutment 28 on the latter and a bracket 29 arranged on the rear wall 3, the rod 25 extending through said bracket. The milling spindles 11 are only displaceable in a radial direction toward the cylinder, whereby only the depth of the cut portion can be determined by the adjustment of 'the spindles in the vertical

direction In order that the milling spindles shall be capable of working off larger portions of the stereotype platens 10, the cylinder 8 carrying these platens is adapted to perform both a rotating and an axial feeding movement on the rigid supporting shaft 5 The cylinder 8 is mounted radially at each end by means of a ball bearing 30 on a bearing holder 31 having a central bore of a diameter somewhat larger than that of the supporting shaft The inner ball race 32 of the bearing 30 is secured to the bearing holder 31, whereas the outer ball race 33 is fitted against the inner surface o; the cylinder 8 Further, three ball bearings 34 are supported on eccentrically adjustable pins 34 ' (Fig 4) on pairs of projections 31 ' on the bearing hold 70 er 31 the central axes of the ball bearings 34 being located in a plane at right angles to the cylinder axis These ball bearings 34 run with the outside of the outer ball racm on a planed surface on the supporting 75 shaft 5 in the longitudinal direction of the latter The t-wo bearing holders 31 are connected mutually by means of three braces 35, 36, 37 extending within the cylinder 8, one of themi, 35 v:: ending along the upper 80 side of the supprtin 2 sha't 5, and the two others, 36, 37 extending along the lower side of the supporting shaft 5 on both sides of a vertical plane through the central axis. Th'e cylinder is ilus rotatably mounted on 85 a carriage displaceable on the supporting shaft 5, said carriage Beinr constituted by the two bearing holders 31 whiich are kept together by means of the three braces 35, 36, 37 The carriage is prevented from rotating 90 by means of a t o;ng devicc consisting of a blcok 38 secured on t'e sjpporting shaft and provided with a hole through which the upper brace 35 extends. Thle two feeding mo eements of the cylin 95 der 8 are effected by means of two hand wheels 39, 40 located on the front side of the machine within convenient reach of the machine attendant The axial movement of the cylinder 8, that is to say, its longitudinal 100 displacement on the supporting shaft 5, is effected by means of the hand wheeel 39 visible on the right in Fig 3 For the purpose in vi w, a guile screw 41 is arranged within the cylinder 3 parallel to the support 105 ing shaft 5, said guide screw being rotatably mounted inl ball bearings 42, 43 inserted into blocks 44, 45 on the supporting shaft 5 The length of the guide screw 41 exceeds in a certain measure the length of a stereotype 110 platen 10, in the longitudinal direction of the cylinder 8 On said guide screw 41 is a nut 46 supporting between a pair of flanges a carrier 47 in the form of a round disk, said carrier floatingly surrounding the supporting 115 shaft 5 while being secured by means of conical pins 47 ' to the three braces 35, 36, 37 that extend through holes in the carrier. The nut 46 is mounted in the carrier 47 with radial play, while axial

play between the nut 120 and the carrier is reduced to the least possible value One end of the guide screw 41 is connected with a drivng shaft 48, which is extended out through the right end wall 2 of the machine and through the right bear 125 ing stand 4, where the end of the shaft is mounted in a bracket 49 and is provided with a spur gear wheel 50 This gear wheel is in engagement with another spur gear wheel 51 on the end of a shaft 52 that ex 130 784,773 tends along the front side of the machine to the right hand-wheel 39 The shaft 52, which is suitably journalled at both ends, is provided with a bevel gear wheel 53 in mesh with another bevel gear wheel 54 on the shaft 55 of the hand wheel 39. The rotary movement of the cylinder 8 is effected by means of an elongated spur gear pinion 56 rotatably mounted within the cylinder, the mounting and the drive of said pinion being similar to those for the guide screw 41 The spur pinion 56 is in engagement with an internally toothed rim 57 secured on the inside of the cylinder 8 The left hand wheel 40 is connected to the long spur pinion 56 by bevel gearing 58, a longitudinally extending outer shaft 59, spur gearing 60 and a shaft 61 extending inwardly through the end of the cylinder 8 The cylinder 8 is also provided at each end with a packing plate 62 which, by means of inserted packing rings 62 ', prevents impurities from penetrating into the cylinder. The milling machine according to the invention thus makes it possible to mill as many as eight stereotype platens 10 at the same time, radial feeding of the milling cutters being provided by operation of the treadle 16, while feeding of the cylinder supporting the platens is performed in the longitudinal direction by means of the right hand wheel 39, and feeding of said cylinder about its axis being effected by means of the left hand wheel 40 By causing one of the cutters to follow as a master the oulines of a platen portion to be milled of, the corresponding portions of the remaining platens will be milled off automatically, provided that the platens 10 have been placed exactly on the cylinder 8 The mounting of the cylinder 8 as above described can be made with such precision that it is possible simultaneously to mill a plurality of platens with an accuracy of + -0 05 mm As the mounting and driving means of the cylinder 8 are located within the cylinder, they are also protected against swarf and impurities that would otherwise prevent the exact functioning of the machine. The invention is not limited to the embocliment herein described and illustrated since modifications may be made in the constructional details Thus, the machine may have fewer or more than eight milling spindles; the driving means of the cylinder may be other than as described, such as by means of hydraulic or electric motors arranged within the cylinder 8, and with control valves and switches arranged

outside the cylinder; also instead of the hand wheels described and shown electric motors may be employed.

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* GB784774 (A)

Description: GB784774 (A) ? 1957-10-16

Improvements in or relating to transformers

Description of GB784774 (A)

PATENT SPECIFICATION 784,774 j Date of Application and filing Complete Specification: March 9, 1956. i Vo 7433/56. Application inade in United States of America on March 14, 1955. Complete Specification Published: October 16, 1957. Index at acceptance:-Class 38 ( 2), Ti F, T 7 (A 2 A: C 1 A C 3 C 6). International Clasificaiion:-1 i 921. COMPLETE SPECIFICATION Improvements in or relating to Transformers EPPATUM SPECIFICATION N Od 784,77 t 4 Page 4, line 37, after "section" insert Uand a substantially U-shaped upper section". THE PATENT OFFICE, 3rd Decemoer, 1957 well known that distribution transformers are subjected to such an operating condition, the NEMA Standards Committee has required that a distribution transformer should be designed to withstand a short circuit current equal to 25 times normal current, and that it shall withstand such current for a predetermined number of cycles depending on certain other requirements The manufacturers, in order to meet this requirement, usually subject

their distribution transformers to a short circuit current which is 40 times as great as the rated current. When the coils of a distribution transformer are tested with currents that exceed normal value by 25 to 40 times, they are subjected to great electromagnetic stresses tending to move them relative to one another If the coils are not so anchored relative to one another that they can withstand these stresses without relative movement, they are not satisfactory for general use If there is a relative movement between the coils, the insulation on one coil will abrade the insulation on the other and in the process of time breakdown will result. Different methods have been tried to so (Price 3,, 45 6 d fl B 00889/2 ( 4) 53 2 1 i D 11/57 R by the two sections of the core cannot be properly closed and high exciiting current 65 and core loss will result If the block is not sufficiently thick, the coil will be loose on the core and movement of the high voltage coil with respect to the low voltage coil will occur on short circuiting 70 The chief object of the present invention is to provide an improved arrangement for anchoring the coils of transformers, such anchoring ensuring against relative movement of the coils when the transformer is 75 subjected to powerful electromagnetic forces resulting from short circuits many times the rated capacity of the transformer. With the above object in view, the invention from one aspect thereof, consists in a 80 transformer comprising a plurality of preformed coils arranged in close proximity, a core comprising a plurality of sections disposed around the coils and a mass of hardened resinous material disposed on the coils 85 and in firm contact with a section of the core, the mass of cured resinous material serving to resist relative movement of the coils when energized. From another aspect, the invention con 90 PATENT SPECIFICATION 784,774 Date of Application and filing Complete Specification: March 9, 1956. J No 7433/56. Application made in United States of America on March 14, 1955. Complete Specification Published: October 16, 1957. Index at acceptance:-Class 38 ( 2), T 1 F, T 7 (A 2 A: C 1 A: C 3: C 6). International Clasificatien:-HO 21. COMPLETE SPECIFICATION Improvements in or relating to Transformers We, WESTINGHOUSE ELECTRIC INTERNATIONAL COMPANY, of 40 Wall Street, New York 5, State of New York, United States of America, a Corporation organised and existing under the laws of the State of Delaware, in said 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 generally to transformers and more particularly to the anchoring of the coils of distribution transformers to prevent relative movement therebetween. In the operation of distribution transformers they are at times subjected to short circuits of indeterminate duration Since it is well known that distribution transformers are subjected to such an operating condition, the NEMA Standards Committee has required that a distribution transformer should be designed to withstand a short circuit current equal to 25 times normal current, and that it shall withstand such current for a predetermined number of cycles depending on certain other requirements The manufacturers, in order to meet this requirement, usually subject their distribution transformers to a short circuit current which is 40 times as great as the rated current. When the coils of a distribution transformer are tested with currents that exceed normal value by 25 to 40 times, they are subjected to great electromagnetic stresses tending to move them relative to one another If the coils are not so anchored relative to one another that they can withstand these stresses without relative movement, they are not satisfactory for general use If there is a relative movement between the coils, the insulation on one coil will abrade the insulation on the other and in the process of time breakdown will result. Different methods have been tried to so (Price 3 sS A mount the core and coils that they cannot move relative to one another under conditions of short circuits which occur in either testing or in use In the manufacture of transformers employing wound cores, the 50 coils are usually braced by mounting blocks on the end frames which exert pressure on both high voltage and low voltage coils and prevent movement of the coils with respect to one another on short circuit 55 On the smaller ratings, this method of assembly is not economical and usually a filler is inserted between the top of the coils and the bottom of the top yoke of the core. The opening is variable and this causes diffi 60 culties in properly filling the space with a compact solid material As an example, if the filling block is too thick, the joint formed by the two sections of the core cannot be properly closed and high exciiting current 65 and core loss will result If the block is not sufficiently thick, the coil will be loose on the core and movement of the high voltage coil with respect to the low voltage coil will occur on short circuiting 70 The chief object of the present invention is to provide an improved arrangement for anchoring the coils of transformers, such anchoring

ensuring against relative movement of the coils when the transformer is 75 subjected to powerful electromagnetic forces resulting from short circuits many times the rated capacity of the transformer. With the above object in view, the invention from one aspect thereof, consists in a 80 transformer comprising a plurality of preformed coils arranged in close proximity, a core comprising a plurality of sections disposed around the coils and a mass of hardened resinous material disposed on the coils 85 and in firm contact with a section of the core, the mass of cured resinous material serving to resist relative movement of the coils when energized. From another aspect, the invention con 90 784,774 sists in a method of manufacturing a transformer such method comprising the steps of arranging a plurality of high voltage and low voltage coils in predetermined relationship to one another, fitting the lower section of a multi-section core in position on the coils, applying a mass of plastic uncured substantially unshrinkable resinous material on the coils, mounting a complementary section of the core over and in contact with the plastic uncured substantially unshrinkable resinous material carried by the coils on the first core section, bonding the core sections to one another and curing the resinous material to provide a cured solid mass between the coils and the core to resist relative movement of the coils when energized. In order that the invention may be more fully understood and readily carried into effect, reference will now be made to the accompanying drawings in which: Figure 1 is a view in side elevation of a wound core transformer showing the core sections separated and a mass of plastic material applied in accordance with the teachings of this invention; and Fig 2 is a view in side elevation of a wound core transformer showing the core sections in engagement with one another with the mass of plastic material disposed between the core and coils to lock them against relative movement in accordance with the teachings of this invention. Referring now to the drawing and more particularly to the modification of the invention illustrated in Fig 1, a transformer shown generally at 10 comprises two wound cores and a plurality of high and low voltage windings Each of the wound cores comprises a bottom section 11 and a top section 12 These cores are made by winding an oriented silicon steel strip to form a wound core of the required thickness which is then impregnated and cut into sections. The cut faces are worked and etched in accordance with the well known practice. The high and low voltage coils are wound to meet predetermined specifications as to size and shape and are generally referred to as preformed coils In this particular instance, two low voltage coils 13

and 14 and a high voltage coil 15 are employed As shown, the low voltage coils 13 and 14 are disposed on opposite sides of the high voltage coil 15 This is a usual arangement. In the building of distribution transformers, different methods have been adopted in an effort to anchor the coils 13, 14 and 15 relative to one another and the core so that there is no relative movement One method employed is to wind the low voltage coil 13 on the high voltage coil 15 so that they lie tightly together and therefore resist relative movement in handling and in operation. However, this has not been entirely satisfactory since slight movement will occur and this is enough to effect abrasion of the conductors Usually the inside low voltage coil 14 is pressed into the high voltage coil. This is not entirely satisfactory since if the 70 coils fit loosely, they are sure to move relative to one another If the coil fits tightly, abrasion is apt to result from the telescoping of the coils. in the interests of economy in manufac 75 ture, the winding of the coils separately and of dimensions that will enable them to be telescoped into one another with a reasonably snug fit is the least expensive Further, when coils fit together in this way, the coils 80 are not damaged in the assembling operations. When the cores and coils have been made as described hereinbefore, two lower core sections 11 have straps 16 fitted around 85 them and are disposed in side by side relation as illustrated The preformed coils 13, 14 and 15 are then fitted into them as shown The low voltage coils 13 and 14 are arranged next to the core iron 90 In order to provide for anchoring the coils 13, i 4 and 15 so that there is no relative movement, a mass of uncured plastic material 17 to be described in detail hereinafter is placed on the ends of the coils as shown 95 The termn "mass" is used in descri'oing the material since it is applied without regard to shape or size It is only necessary to e-nploy a small mass of the material and apply it to the upper ends of the coils The 100 quantity of uncured plastic material employed in conjunction with each core will be small since usually the preformed coils 13, 14 and 15 substantially fill the cores It is not necessary that thile mass of material be 105 measured with great care, since if it is slightly excessive when the top sections 12 of the cores are fitted into position, the uncured plastic material will flow outwardly on the ends of the coils 110 When the top sections 12 of the cores are pressed into position as shown in Fig 2, the worl -ed and etched faces on the core sections fit tightly together, forming a low loss butt joint as is well known in this art The straps 115 16 are then drawn around the cores, tying the core sections 11 and 12 tightly together. It will be observed that masses of plastic material 18 are shown

disposed between the core sections 11 and the lower ends of the 120 coils 13, 14 and 15 It has been found that good results in the anchoring of the coils relative to one another and to the core can be effected without em nploying the masses of uncured plastic material 18 However, it is 125 to be understood that if desired an uncured plastic material can be dropped into position in the core sections 11 before the preformed coils 13, 14 and 15 are assembled in the core sections 130 at room temperature and that it hardens satisfactorily at about 125 C When hardened this mixture definitely anchored the core and coils so that there was no relative movement of the coils 70 In the preceding examples fillers were referred to and many inert fillers are available for use In the tests made the fillers employed were silica, magnesia and alumina. These fillers may be used alone or in comrn 75 bination In practice it was found that it was desirable to have from 20 % to 65 % filler in the putty-like masses It is well known that the fillers reduce shrinkage of the resinous materials so that the space be 80 tween the coils and core will remain completely filled. It is also pointed out that it is desirable to be careful in the use of solvents In the tests made, care was observed to avoid sol 85 vents in such an amount as to form gas pockets during the curing of the resinous materials Such gas pockets become ionized under certain conditions and reduce the impulse strength of the transformer 90 As pointed out hereinbefore, generally the applying of a plastic mass between the upper ends of the coils and the upper sections 12 of the core is adequate for anchoring the coils to prevent movei ent as the re 95 sult of short circuit tests or short circuits during use and during the handling of the transformers However, in special circumstances in order to withstand maximum electromagnetic stresses, transformers may be 100 made with cured resinous masses between both ends of the coils and transformer core. It will be readily appreciated that when the space between the coils and core are completely filled that there can be no movement 105 of the coils relative to one another or to the core. In applying the plastic mass composed of filler and heat hardenable resin as pointed out in the assembly of the core, this material 110 will flow to fill up the gap between the bottom of the core yoke and the top of the coil section Another method of accomplishing this is to use the equivalent of a flowed plastic mass This can be accomplished by 115 pre-dipping glass matting or other suitable fibrous nraterial in a suitable resin solution whereby the individual glass fibers of the mat are coated with heat hardenable resin. This glass matting after treatment is capable 120 of compression under stress as much as 50 % to 75 % of its thickness and when baked in the

compressed condition will form a hard filler capable of withstanding the short circuit stresses and preventing coil movement 125 In assembling the transformer, the coils would first be assembled in the bottom coil section 11 after which a varnish or resin treated pad is placed on top of the coil sections over which the top core section 12 is 130 Many different materials have been used with sucess in anchoring the coils 13, 14 and to prevent relative movement In selecting the material, it is essential to keep in mind that it must remain sufficiently hard to anchor the coils 13, 14 and 15 at temperatures up to 95 C which at the present time is the top operating temperature of transformers of this type However, as time goes on the operating temperatures of transformers may be higher and materials which will have sufficient strength to hold the coils against relative movement are readily available to meet the higher temperature demand. it has been found that thermoset resinous materials are highly satisfactory It has also been established that by selecting the proper individual or mixed resinous materials with high melting temperatures, they will meet different operating requirements for transformers. In tests made, good results were obtained by preparing thermosettable phenolic type resins and loading them with fillers to bring them to a plastic state having a consistency somewhat similar to the well known material known as putty In this condition the thermosettable phenolic resins when applied to the upper ends of the core in a small mass will not flow, but can be made to conform to the shape of the inside of the core when the upper sections 12 are pressed into position This putty-like mass of phenolic type resin will harden when cured in the baking of the transformers. Other heat hardening resins that were found satisfactory are urea formaldehyde and melamine formaldehyde These resinous materials are also prepared with a certain quantity of filler intimately mixed with them When so prepared and applied, the putty-like mass of these resins will not flow, and will cure readily in the baking step of treating transformers. Another material that has been found highly satisfactory in anchoring the coils of distribution transformers comprises completely reactive low molecular weight epoxy resins or elycidyl polyethers when brought to a putty-like state with the introduction of suitable fillers This material should be properly catalyzed to give it good shelf life at room temperature and render it heat hardenable in a temperature range of 100 C to 125 C. A putty-like mass which was found very satisfactory comprised a 100 % solids, low molecular weight enoxy resin to which was added a suitable filler and 4 % by weight of triethanolamine borate and about 1 % of chromium acetoyl acetonate The chromium acetonyl acetonate co-onerates

to promote the catalytic reaction of the epoxy resin and the triethanolamine borate It was found that this mixture has a very long shelf life 784,774 784,774 placed The glass mat should be suffilciently thick to allow for some compression under all conditions of assembly and thus compensate for variable distance between the bottom of the core yoke and the top of the coil section In the drying process of the transformer where temperatures of the order of C to 135 C are used, the plasticized pre-treated pad or glass filler would cure to a solid mass This would give complete filling of the space between the top of the coil section and the bottom of the core yoke and thus prevent any movement of the coils with respect to the coil during shipping, hand ling, or under conditions of short circuit.

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* GB784775 (A)

Description: GB784775 (A) ? 1957-10-16

Improvements in infinitely variable delivery volume controls or steplessdelivery governors for displacement or piston compressors

Description of GB784775 (A)

PATENT SPECIFICATION 7849775 Date of Application and filing Complete Specification: March 20, 1956. No 8662/56. Application made in Austria on April 19, 1955. Complete Specification Published: October 16, 1957. Index at acceptance:-Class St( 1), C 2 D 2 E. International Classifieation:-F 194 c. COMPLETE SPECIFICATION

Improvements in Infinitely Variable Delivery Volume Controls or Stepless Delivery Governors for Displacement or Piston Compressors We, E N F O ENTWICKLUNGS-UND Fo RsCHUNGS AKTIENGESELLSCHAFT, a body corporate organised under the laws of Liechtenstein, of Vaduz, Liechtenstein, 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:- The known system of so called " static head " or "reflex " governing of displacement or piston compressors is based on the property inherent in the manner of working of such machines, that when the suction valve plate is held open the medium flowing back into the suction pipe during the compression stroke exerts a force tending to close said valve Owing to the periodic variation of the piston speed between zero and a maximum this force is likewise of a magnitude varying periodically between zero and a maximum, the peak value of the dynamic forces acting on the valve plate experiencing a time lag with regard to the peak piston speed by virtue of the occuring throttling phenomena. When the value of the force holding the valve open, hereinafter referred to as the open holding force, is made to vary continuously between zero and a maximum a time lag occurs in the establishment of the equilibrium condition between the open holding force and the sum of all forces acting to close the valve This enables the commencement of closing of the valve to be arbitrarily varied between two points in the compression period (at the commencement thereof and the point corresponding to the maximum of the closing force) whereby the delivery volume of the compressor can likewise be caused to vary infinitely between maximum output and a minimum value. The holding open of the suction valve plate has hitherto been performed principally by lifting devices in the form of dent(Price 3 s 6 d) ated rings (so-called "grippers"), usually of welded sheet metal and projecting with their prongs through the passages in the valve seatings to actuate the valve plate. Since, as already mentioned, the motion 50 of the valve plate is periodic, the grippers must likewise be given a more or less similar periodic action The consequent acceleration and retardation phenomena and the considerable mass of the existing forms of the 55 grippers give rise to exceptionally high stresses in the valve plate and lifting elements, particularly in the case of a high speed compressor, making undisturbed operation wellnigh impossible 60 In order to reduce the mass of weight of the grippers and obtain more effective guiding of the lifting elements, it has been proposed to divide the gripper ring into individual pins and to guide such pins in the 65 valve seat,

in particular in the localities of the crossing points of the radial arms with the annular seating ribs The saving in moving mass is in this case very slight. Patent Specifications 734904 and 708346 70 disclose arrangements for relieving the compressor during starting wherein the valve plates are lifted off their seats by a system of rods, or a connection to the lubricating oil pressure system, a pressure ring and a 75 number or rods Hereto, apart from the other differences in the arrangement, the masses to be moved are considerable and consequently unsuitable for the purpose of the present invention 80 Suggestions for performing static pressure volume governing have also been made according to which grippers or lifters transmitting the spring force to the valve plate are interconnected by shock-absorbing link 85 ing elements not participating in the governor action Such shock-absorbing linking elements are of an elastic substance such as rubber or the like enclosed between each lifting pin and a corresponding surrounding 90 784,775 sleeve. The subject of the present invention is an infinitely variable delivery volume control or stepless governor for displacement or piston compressors, in particular compressors for high running speeds, acting by retarding the closing of the suction valve by varying the open holding force acting on the valve plate by means of a plurality of helical springs, in which the masses moving in direct conjunction with the valve plate or plates, (individual rings) and consequently the forces exerted by these (accelerations, retardations and shocks) are reduced to the greatest possible extent. By way of example an embodiment of the invention is illustrated in the accompanying drawing. Fig 1 represents a general arrangement showing the governor in mid-section. Fig 2 is a partial view of the suction valve seating from the compressor cylinder side. Fig 3 is a section through a lifting pin in a pressed-in bush. Fig 4 is a section through a lifting pin in a screw-in intermediate sleeve with a pressed-in bushing. The suction valve comprising the valve seat 1, valve guard plate 2, central screw spindle 3, guide ring 4, valve plate 5 and damping plate 6, is held by the distance sleeve 7 against the seating 8 of the cylinder 9 which is closed by the valve cover 10. Differing from known arrangement, the spring forces are transmitted to the valve plate 5 by means of single-piece lifting pins 11 passing through smooth holes in the radial ribs 12 of the suction valve seat 1 or through guide bushes 12 a which are either press-fitted in the radial ribs 12 (Fig 3) or are screwed in together with intermediate

guide bushings 12 b (Fig 4) and which consist of a material with suitably low friction properties such as sintered metal, carbon, graphite, plastic with special fillers or the like. The lifting pins 11 are formed in their parts nearest to the valve cover 10 with collars 13 against which bear on the one hand the lifting springs 14 and on the other hand the pin returning springs 15 The springsupporting collars of the lifting pins or more precisely the faces 15 a of the pins abut against the valve seat 1 (or against a fixed stop thereon, not shown) before the valve plate 5 has been fully lifted, i e before the valve has been competely opened. Guide pins 21 for the lifting springs 14 are provided and are so dimensioned that, when these springs are compressed to a value corresponding to the maximum reflux force or the required minimum output, they bear directly on the lifting pins 11 in such a manner that a direct transmission of force to the lifting pins takes place with elimination of the action of said springs and consequently the suction valve plate 5 is continuously held open (no load position) and simultaneously makes contact with the lifting pins. F Gr the purpose of applying comnpressive 70 force to the springs acting on the lifting pins 11 a pressure plate 16 is provided which is vertically movable with reference to the valve seat 1 and is secured against twisting or rotating by essentially known means such 75 as guide pins 17 fixed to the valve seat This pressure plate 16 is positioned on the central screw spindle 3 of the valve by a pressure plate bush 18 and a locating nut 19. A pressure plate return spring 20 presses the 80 pressure plate away from the valve seat 1. Lateral buckl'ng of the lifting springs 14 is prevented by the already mentioned guide pins 21 the ends of which have pads 22 of some shock absorbing material such as rub 85 her or the like, or metallic damping elements such as spring washers or rings or plate springs, in order to prevent the occurence of disturbing noises due to intermittent contact of the lifting pins 11 and the guide pins 90 21 immediately preceding the minimum output position The drawing (Fig 1) shows an embodiment in which the ends 22 a of the lifting pins 11 that are nearest the pressure plate 16 are of smaller diameter 95 than the pads 22 of the guide pins 21 This has the purpose of affording some degree of play for the mass of each pad 22 in the event of abrupt collision between the parts 22 and 22 a 100 The transmission of force to the pressure plate 16 is effected by means of a structural assembly consisting of a piston 23 and a pushrod 24 The pishrod is passed gastight through the valve cover in a bush 25, 105 and the sealing of the piston in its cylinder 26 is effected by means of a sealing ring 27. The sealing of the piston 23 in the cylinder 26 can also be effected

by grinding in or by other sealing means such as grooved rings, 110 dished collars, piston rings or the like Any leakages which may become dangerous if inflammable or toxic gases are compressed are intercepted by a lead-off connection 28. Pressure on the piston 23 of the cylinder 115 26 is applied through the intermediary of a pressure fluid 29 in a container 30, such pressure fluid being itself acted upon by compressed air or gas entering through a pressure feed pipe 31 The container is 120 equipped with a filling screw plug 32 and a draining screw plug 33 A nozzle 35 following on the connecting passage 34 throttles the fluid supply and thus damps the oscillations of the power transmitting system 125 The free flow cross section of this nozzle can be varied, for instance by an adjustable nozzle needle. The essentially known means provided for preventing oscillation of the pressure plate 130 guide bushes are pressed into intermediate bushes which are screwed-threaded into corresponding tapped holes in the valve seat. 6 A stepless delivery governor in accord-

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* GB784776 (A)

Description: GB784776 (A) ? 1957-10-16

Means for preventing the loosening of screw-cap electric lamps in screw-threaded lamp holder sockets

Description of GB784776 (A)

PATENT SPECIFICATION Date of Application and filing Complete Specification: April 20, 1956.

No 12140/56. Application made in France on April 25, 1955. r Complete Specification Published: October 16, 1957. Index ant acceptance:-Class 3 $( 1), E 3 (A 61 H: B 2 C: C 2 C: CZE: C 9: C 11: E 3 A E 3 B). International Classification:-HG 2 f. COMPLETE SPECIFICATION Means for Preventing the Loosening of Screw-cap Electric Lamps in Screw-threaded Lamp Holder Sockets We, CHANTIERS DE L'ATLANTIQUE (PENHOET-LOIRE), of 7 rue Auber, Paris ( 9), France, a French Body Corporate, and HENRI PIERRE FRANCIS MONFORT, of Avenue des Ormes, La Baule, Loire Inf 6 rieure, France, a French Citizen, 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 electric lamp and socket assemblies in which the lamp is provided with a screw-threaded cap adapted to be screwed into a complementary screwthreaded lamp-holder socket. When such assemblies are subjected to vibration, the lamp is liable to become partly disengaged or loosened, so that the cooperating central contact members of the lamp cap and socket do not make efficient contact with each other, the power supply to the lamp may therefore be cut off intermittently or completely Prolonged vibration has been known to loosen the assembly to such an extent as to allow the lamp to drop out from its socket. It is an object of the present invention to overcome this difficulty and to provide means for preventing the loosening of the lamp and socket assembly, whereby efficient electrical contact between the co-operating central contacts of the lamp cap and socket will be maintained, even in case of violent vibration imparted thereto and over long periods of time. The invention provides means for preventing the loosening of a screw-cap electric lamp from its socket, characterised in that the co-operating central contact members of the lamp cap and socket include one springmounted contact member, and that at least one of said contact members is formed with substantially radial teeth, grooves, notches or the like for engagement with the other of said contact members when the lamp is (Price 3 s 6 d) screwed into operative position. An exemplary embodiment of the invention will now be described for purposes of illustration but not of limitation, with reference to the accompanying drawing, wherein: 50 Fig 1 is a general elevation showing the lamp and its socket in disconnected condition, and with part of the socket broken away.

Fig 2 is an inverted plan of the lamp 55 Fig 3 is an overhead plan of the socket. As shown, the electric lamp comprises a bulb attached to a conventional ca D or base portion 1 formed with external screw threads and having a contact member 2, made of 60 brass or other suitable metal, projecting centrally therefrom and insulated from the -threaded side wall of the cap Bonded to the end face of the contact member 2, as by soldering, brazing or otherwise, is a conduct 65 ive disc element 3 which, as shown in Figs. 1 and 2, is formed with radially extending teeth or notches 4 of saw-tooth configuration on its outer end face. The lamp holder socket comprises a con 70 ventional wall portion 5 formed with screw threads complementary to those on the lamp cap, this socket portion 5 being mounted upon an insulating base support 7 In accordance with the invention, there is mounted 75 on the support 7, within the socket portion 5, a U-shaped spring strip 9 suitably connected to one supply terminal 8 in the support 7, while the other supply terminal 8 is connected to the socket portion 5, in a con 80 ventional manner, as shown in Fig 3 The upper leaf of the U-shaped spring strip 9 is adapted to make contact with the lamp contact member 2 by way of the disc element 3 There is bonded to this upper face 85 of the upper leaf of the spring strip 9 a disc 6, similar to the disc 3 and similarly provided with radial saw-teeth or notches 11 thereon so directed as to fit with the saw teeth or notches 4 on disc 3 when the discs 90 784,776 are pressed together. When the lamp cap 1 is screwed into the socket portion 5, the disc 3 will be brought gradually into engagement with the disc 6, the teeth of the two discs snapping over one another as the lamp is turned until the lamp cap has been screwed home tight in the socket portion 5 Thereafter the teeth act to prevent a loosening of the threaded assembly even under strong vibratory stress. It will be appreciated that a screw-cap electric lamp provided with a toothed disc 3 according to the invention may be used in association with a conventional lamp holder socket which does not include a toothed disc 6, and that conversely a conventional lamp cap which does not incorporate the toothed disc 3 can still be used with an improved socket that includes a toothed disc 6. Many departures may be made from the single embodiment illustrated herein without departing from the scope of the invention as defined in the appended claims Thus, the co-operating gripping means, herein shown as radial saw teeth, may be provided in a variety of other forms Also the invention may be applied to screw-socket lamp holders of other types than that shown. Further the spring contact mount, instead of comprising a U-spring 9

as herein described, may comprise a spring-biassed plunger; in such case, the teeth or equivalent gripping means would be provided on the top end face of the plunger Furthermore, the teeth or equivalent gripping means may be formed directly on the co-operating surfaces of the respective contacts in the lamp cap and its socket, instead of being formed on discs or like elements bonded to such 40 surfaces.

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* GB784777 (A)

Description: GB784777 (A) ? 1957-10-16

Electric switch

Description of GB784777 (A)

PATENT SPECIFICATION Date of Application and filing Complete Specification: april 26, 1956. No 12777/56. Application made in United States of America on May 20, 1955. Complete Specification Published: October 16, 1957. Index at acceptance:-Class 38 ( 5), Bl D( 1 A: 3), B 2 812. International Classification:-HI On 1102 c. COMPLETE SPECIFICATION Electric Switch We, SQUARE D COMPANY of 6060 Rivard Street, Detroit 11, Michigan, United States of America, a corporation organized and existing under the laws of the State of Michigan, 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: -

The present invention relates to improvements in electrical switches which may be of the interlock type. It is an object of the present invention to simplify the construction of an interlock type switch which is convertable from a normally open to a normally closed switch or vice versa. According to the present invention there is provided an electrical switch comprising an insulating base with a recess centrally thereof and aligned apertures extending through the walls of the base from the recess a fixed contact member in said recess, a movable contact member for cooperating with said fixed contact member, said movable contact member being operable by an operating member extending through one of said apertures and externally of the base, spring means biasing said movable contact member with respect to the fixed contact member, the said movable contact member, operating member and spring means being associated as a unit which is reversibly mountable with respect to the said base so as thereby to convert the switch from a normally open to a normally closed switch or vice versa. Reference is now made to the accompanying drawing which illustrates an embodiment of the present invention here given by way of example and in which: Figure 1 is a top plan view of a switch with the side cover removed and showing the switch as a normally closed type. (Price 3 s 6 d) Figure 2 is a top plan view with side cover removed and showing the switch as a normally open type. Figure 3 is a sectional view taken along the lines III III of Figure 1, but showing 50 the side cover in place. Figure 4 is an exploded perspective view of the external operator and internal mechanism of the switch. The embodiment illustrated is a switch 55 useable as an interlock type switch and which comprises an insulating base I having a central recessed portion at 2 and slots at 3 and 4 extending from the recessed portion 2 to the exterior of the base in which 60 are positioned conducting straps 5 and 6 carrying stationary contacts 7 and 8 at one end within the recess 2 and terminals 9 and 11 at the other end and outside of the base 1. By interlocking switch is meant a switch suitable for use as a pilot switch operated by a moving part of a larger switch to perform a control function in the control system of the larger switch or in an associated 70 control system. The insulating base 1 is further provided with coaxial grooves 12 and 13 opening at one end to the exterior of the base 1 and at the other end to the central recessed por 75 tion 2 containing the stationary contacts 7 and 8 Conducting strap 5 passes transverse of the groove 12 and is cut out to conform to the dimensions of the grooves and to provide side slots at 14 and 15 along the 80 grooves 12 Groove 13 is

likewise provided with side slots 16 and 17 to provide side slots in exact complement with those designated 14 and 15 for a purpose to be explained hereinafter When the cover 34 is 85 in place, the grooves 12, 13 are closed to form apertures aforesaid. Referring now to Figure 1 and the exploded view of Figure 4, the switch operating mechanism comprises an operating member 90 784 J 77 784,777 18 of a suitable insulating material having an extending spring guide probe 19 The operating member 18 is adapted to be moved axially by a moving part of an electromagnetic contactor upon operation of the contactor, thereby to cause the switch to perform a control function in relation to the movable position of the contactor part A movable contact member 21 is supported on the probe portion 19 and is spring pressed towards the end of the probe by a helical spring 22 pressing at one end against the body portion of the operator 18 and at the other end against the contact member 21. The movable contact member 21 carries at its opposite ends movable contacts 20 and which are maintained in operative alignment with the stationary contacts 7 and 8 in the recess 2 A spring retainer 23 cooperates with a groove 24 on the probe 19 to retain the contact member 21 in mounted position on the operator 18 and the contact member 21 is spring pressed into a normal position either open or closed, as will be seen, by helical spring 25 pressing at one end against the contact member 21 and the other end against spring seat 26 which is retained in the base 1. The operating member 18 and the spring seat 26 are provided with means cooperating with the base 1 to maintain them in position and alignment as will be seen by reference to Figure 3 and 4 The operating member 18 is provided with a semi-circular guide and barrier 27 on its under side acting as a guide during the travel of the operator in switch operation and as a stop for travel of the operator in open position as will be seen hereinafter Spring seat 26 is provided with radial extensions 28 and 29 which cooperate with the grooves 14 and 15 or 16 and 17, depending upon the location of the spring seat, and with an end barrier 31 extending generally below the axis of the spring seat as shown in Figure 3 It should be noted that the dimensions of the base at 32 with which the barrier cooperates in the device, as shown in Figure 3, is the same as the total dimension of the corresponding portion 33 of the base on the opposite side plus the thickness of the strap 5 which, as has been previously described, is cut out to conform with grooves 12 in the base and to provide slots 14 and 15 so that all the operator parts may be positioned at either side of the base 1. Referring now to Figures 1 and 2 illustrating the assembled switch in its two conditions, it may be seen that the switch provides the adjustability of being either a normally open or a normally closed

type of switch. The switch provides for ready reversal from one type to the other by merely removing the side cover and reversing the operating mechanism thereof as by lifting the entire mechanism out and reversing it in the base. The parts which constitute the operating mechanismn are readily positionable in either side of the base and, as has been shown, the base is provided with complementary 70 grooves on each side to accommodate the operator at either side For instance, the portion 32 of the base corresponds in dimension with the dimnension of portion 33 and the conducting strap 5 so that end post 26 75 will fit in the base and be flushed with its exterior regardless of on which side it is mounted Likewise, the grooves established by slots 16 and 17 are complementary with the slots 14 and 15 established by the cut 80 out in the strap 5 in its position in slot 3. With the operating mechanism in its position as illustrated in Figure 1, the switch constitutes a normally closed switch with contacts 7-20 and 8-30 in engagement Move 85 ment of the operator opens the contacts and breaks its associated circuit In Figure 2 the contacts are in a ncr:nally open position with movement of the operator closing the contacts ' With the operator in this latter 90 pcsition, the barrier 27 on the operator 18 cooperates with portion 32 cf the base to establish an end stop for the barrier.

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