Download - Xiaomi Air 12 Notebook - PennEngineering · Xiaomi Air 12 Notebook has ultra-thin, full-metal design, edge to edge glass coverage, a sleek appearance, lite up keyboard, and ultra-light

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Xiaomi Air 12 Notebook

June 5th, 2017

Xiaoming Chen

PennEngineering®

http://www.pemnet.com/

© 2017 www.pemnet.com 2

Overview

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Xiaomi Air 12 Notebook has ultra-thin, full-metal design, edge to edge glass coverage, a

sleek appearance, lite up keyboard, and ultra-light weight design featuring the latest

hardware. The Notebook is extremely portable and can be carried around effortlessly

making it a perfect laptop to carry.



Details & Findings

Pictures and Description of the

Xiaomi Air 12 Notebook and the

Disassembly Process.

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Xiaomi Air 12 Notebook Teardown

Step 1: Power off Xiaomi Air 12 notebook.

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Xiaomi Air 12 Notebook Teardown Step 2: Removing bottom case

Xiaomi Air 12 Notebook uses eight M2x3.3 (circled in Pink), CD finish with shoulder screws to secure

the bottom case. In the middle of the bottom case on the right side, one screw is under the a rubber foot. We pry

the bottom case with a pick or plastic card and then slide the pick by the edges until removing the bottom case

completely.

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The screw details are as below

• M2 x 3.3 mm overall length

• 3.65 mm head diameter

• 0.3 mm head thickness

• 2.3 mm shoulder diameter

• 0.4 mm shoulder length

• Nylon locking patch

• #4 Phillips drive

• CD finish

• Flat head

• 400 series S/S




Step 2: Removing bottom case

The below pictures show the CD finish, shoulder screw geometry.

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Step 2: Removing bottom case

The below picture and schematic diagram illustrate joining structure for the molded-in brass inserts.

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Xiaomi Air 12 Notebook Teardown Step 3: Separating speaker modules

We disconnect the flex cable before removing the two speaker modules. Total four molded plastic

tapered pins position the two speaker modules, two pins for each speaker module.

In this step, no mechanical fasteners, adhesive involved in the joining.

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Xiaomi Air 12 Notebook Teardown Step 4: Removing battery

Total four black oxided M1.8 screws used to hold the battery secure. The M1.8 screws (circled in Pink)

on the left side go through the holes and then through the threads in the brass inserts illustrated on slide #11. The

M1.8 screws circled in Red in the middle go through the holes in a stainless steel made battery cover and then

through the threads of the standoffs illustrated in slide #12.

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• M1.8 x 2.75 mm overall length





• Flat head

• Carbon Steel + Black Oxided




Two flat head M1.4 screws with plastic washers are used to hold the battery. The screws (circled in

Blue) attach on the standoffs illustrated on slide #13.

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• Flat head

• Carbon Steel + Bright Nickel

The washer details are as below

• O.D.: 4.85mm

• I.D.: 2.40mm

• Thickness: 0.8mm

• Plastic




The below pictures illustrate joining structure for the two black oxided M1.8 screws used.

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Black oxided screws on the left side



Xiaomi Air 12 Notebook Teardown Step 4: Removing keyboard cover

The following designs represent the joining structure for the two black oxided M1.8 screws used. The

standoff illustrated below is made of carbon steel with Bright Nickel plating.

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Xiaomi Air 12 Notebook Teardown Step 4: Removing keyboard cover

The below pictures represent joining structure for the two flat head M1.4 screws with plastic washers.

The standoff illustrated below is made of carbon steel with Bright Nickel plating.

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Step 5: Removing battery cover

The battery cover stamped with 0.2mm stainless steel panel and secured by eight snap fits with large

clearance between the male and female snapping elements.

In this step, no mechanical fasteners were used.

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Xiaomi Air 12 Notebook Teardown Step 6: Removing hard disc drive

One M1.4 flat head screw secures the hard drive on the aluminum alloy chassis with the threads inside

the standoff (circled in Pink) illustrated below.

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• Machined


• Flat head





Step 6: Removing hard disc drive

The following picture and schematic diagram illustrates joining structure for the flat head M1.4 screw

used. The standoff illustrated below is made of carbon steel with Bright Nickel plating.

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Xiaomi Air 12 Notebook Teardown Step 7: Removing the motherboard

Total eight flat head M1.8 screws (circled in Pink) are used to secure the motherboard. Six of the

screws go through the holes in the circuit board and then attach on the brass inserts illustrated on slide #18. The

remaining screws (in the middle) go through the circuit board and then attach on the standoffs clinched into sheet

metal beneath aluminum chassis as shown on slide #19.

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• Machined


• Flat head

• Carbon Steel + Black Oixded




Step 7: Removing the motherboard

The following pictures and schematic diagrams illustrate joining structures for the flat head M1.8 screw

used. The insert illustrated below is made of brass with Silver coating.

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6x Black oxided screws around the side




Step 7: Removing motherboard

The following pictures and schematic diagrams illustrate joining structures for the flat head M1.8 screw

used. The standoff illustrated below is made of carbon steel with Bright Nickel plating.

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2x Black oxided screws in the middle




Step 8: Removing touchpad

Three M1.8 flat head screws are used in the touchpad secure. The screws go through the holes itself and

then into the threads inside the molded-in brass inserts illustrated on slide #21.

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• Machined


• Flat head





Step 8: Removing touchpad

The following picture and schematic diagrams illustrate joining structures for the flat head M1.8 screw

used. The insert illustrated below is made of brass with Silver coating.

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Step 9: Removing Audio Jack input/output

Two flat head M1.8 screws (circled in Pink) are used to hold the audio jack. The screws hold the circuit

board and on to the molded-in brass inserts illustrated on slide #23.

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• Machined


• Flat head





Step 9: Removing Audio Jack input/output

The following picture and schematic diagram illustrate the two flat head M1.8 screws that mate with

the machined molded-in brass insert. The insert illustrated below is made of brass with Silver coating.

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Xiaomi Air 12 Notebook Teardown Step 10: Removing the Keyboard

Total thirty-eight flat head M1 screws (circled in Pink) are used to hold the keyboard with self clinching micro

standoffs illustrated on slide #27.

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• M1 x 1.4 mm overall length




• Machined


• Flat head





Step 10: Removing the Keyboard

For positioning the keyboard in the right place, two guide pins (circled in Pink) are used in the keyboard

componen. The guide pin is made of carbon steel with Bright Nickel plating.

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Step 10: Removing the keyboard component

The following drawing illustrates the guide pin outside dimensions. The guide pin illustrated below is

made of carbon steel with Bright Nickel plating.

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Xiaomi Air 12 Notebook Teardown Step 10: Removing the keyboard component

The following picture and schematic diagram illustrates the two flat head M1.8 screws that the external

threads engage in the threads that are machined inside of the micro standoffs.

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Xiaomi Air 12 Notebook Teardown Step 10: Removing the keyboard component

The keyboard component consists of 78 pieces of typing keys, 0.2mm stainless steel made of sheet

metal panel and nonmetal film made of insulating layer at the bottom. The joints between the 0.2mm keys and

the metal panel, the metal panel and insulating layer are snap fits and adhesion bond.

In this step, no mechanical fasteners were found.

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Step 11: Removing the hinge

The two hinges are secured to the aluminum alloy chassis by six M1.8 screws fastening into the

threads inside of the molded-in micro inserts illustrated on slide #30.

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• Machined


• Flat head





Step 11: Removing the hinge

The following picture and schematic diagram illustrates the six flat head M1.8 screws that the

external threads engage in the threads that are machined inside of the molded-in inserts. The insert illustrated

below is made of brass with Silver coating. The plastic frame is also covered with Silver coating.

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Step 12: Removing the metal-spring-contact and liquid crystal displayer (LCD).

The metal-spring-contact fastened by five flat head M1.4x2.3 screws (circled in Blue) used in the threads

inside SMT soldered on the motherboard illustrated below and on slide #32.

The LCD assembly can easily be detached with using a pick and a hair drier. The displayer is

fastened with double-sided adhesive tapes. In this sub-step, no any mechanical fastener found.

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• Machined


• Flat head





Step 12: Removing the metal-spring-contact and liquid crystal displayer (LCD).

The following picture and schematic diagram illustrates the five flat head M1.4 screws that

engage in the threads that are machined inside the SMT micro nuts.

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In the below picture lay all the components that we disassembled from the teardown:




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The following pictures illustrate the fasteners installed into the aluminum chassis on slides #12, #13, #16, #19,

#21, #25 and #27.

Back side of the aluminum chassis

Front side of the aluminum chassis



Fastener Summary



Fasteners Summary

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Total of 169 fasteners used in this laptop, give the notebook rigidity and make the notebook easy to disassemble. All of the fasteners in the device are listed in the table below:

Item Thread Overall Length Head Dia. Head Thick. Driver Finish Nylock Qty. Slide No

1 M2 Screw 3.3 3.65 0.3 Phillips #4 CD Finish Yes 8 #5; #6

2 M1.8 Screw 2.75 4.3 0.51 Phillips #0 Black Oxided Yes 4 #9

3 M1.4 Screw 1.9 5 0.48 Phillips #0 Black Oxided Yes 2 #10

4 M1.4 Screw 1.95 5.1 0.45 Phillips #0 Bright Nickel Yes 1 #15


6 M1.8 Screw 2.65 4.4 0.5 Phillips #0 Black Oxided Yes 5 #20, #22

7 M1 Screw 1.4 2.3 0.3 Phillips #00 Bright Nickel Yes 38 #24

8 M1.8 Screw 4.6 3.6 0.75 Phillips #1 Bright Nickel Yes 6 #29


10 M1.4 SMT Micro Nut 1.6 / / / Tin-Plated / 5 #32

11 M1.8 Micro Molded-in Nut 2.75 / / / / / 6 #30

12 M1.8 Micro Molded-in Nut 2.25 / / / / / 21 #11,#18,#21,#23

13 M2 Micro Molded-in Nut 2.25 / / / / / 8 #7

14 M1.0 Micro Standoff 1.6 / / / Bright Nickel / 38 #27

15 M1.4 Micro Standoff 2.88 / / / Bright Nickel / 3 #13,#16



18 φ1.90 X 3.4 Guide Pin 3.4 / / / Bright Nickel / 2 #25, #26

19 φ4.85/φ2.4 X 0.8 Plastic Washer 0.8 / / / / / 2 #10



Fasteners Summary

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All fasteners found in the device are categorized in the following 8 groups:

• M1, M1.4, M1.8, M2


• Phillips drive

• Flat head

• Carbon steel + Finish

• Quantity: 77

• Reference slide #5, #6 , #9

#10 , #15 , #17 , #20

#22, #24, #29, #31

• M1.8, M2

• 2.25 mm overall length

• Thread class: 6H

• Quantity: 29

• Reference slide #7, #11, #18,

#21, #23

• φ1.90

• Thread class: N/A

• Quantity: 2

• Reference slide #25, #26

• M1.4



• Quantity: 5

• Reference slide #31



Fasteners Summary

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• M1



• Quantity: 38


• M1.8



• Quantity: 6


• M1.8



• Quantity: 7

• Reference slide #12, #13, #16,

#19


• O.D. : 4.85 mm

• O.D. : 2.4 mm

• Thread class: N/A

• Quantity: 2




Alternate Solutions

PennEngineering® recommendations of alternate hardware and cost savings

opportunities.

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Section Heading Slide – Do Not Remove



Alternate Solutions


PennEngineering® is fully capable of making all of the fasteners shown on slides #36, #37,

#38. In addition to direct replacement and perhaps some manufacturing and material

substitution for functional and cost improvement, some alternate fastening suggestions are

presented for specific situations in the following slides.



Alternate Solutions


• Micro screws alternative solution:

As an alternative approach, all of the micro screws can be replaced by PennEngineering®

manufactured micro screws. PEM has license with Microstix®, Torx® and Torx Plus® driver and

self-tapping thread patent as like TAPTITE®, FASTITE®, REMFORM® and REMFORM F® with

different design solutions.



Alternate Solutions


• M1 Screw alternative solution I:

The M1 screws are used to fix & connect the keyboard with the main aluminum chassis body.

All of the M1 screws can be replaced with PennEngineering® TKA™/TK4™ microPEM®

TackSert® Pins can be used in this case to replace the joints. Installation will be more fast by

press-in to replace turn-in. The parts however is supposed to use in applications where

disassembly is not required.



Alternate Solutions


• M1 Screw alternative solution II:


All of the M1 screws can be replaced with PennEngineering® TA™/T4™ microPEM® TackPin®

Fasteners. The solution enables sheet-to-sheet attachment, replacing costly screw installation in

applications where disassembly is not required.



Alternate Solutions


• M1 Screw alternative solution III:


All of the M1 screws can be replaced with PennEngineering® TS4™ microPEM®

TackScrew™ Fasteners. The microPEM® TS4™ enables cost effective sheet-to-sheet

attachment by simply pressing into place and can be removed by simply unscrewing, similar to

original threaded fasteners.



Alternate Solutions


• Micro Molded-in Inserts alternative solution:

MicroPEM® thru-threaded brass inserts for plastics introduce ideal fastener solutions to

attach components in compact electronic assemblies. The Micro Molded-in Nut can be

replaced by Type MSIB™ microPEM® Brass Inserts from PennEngineering® . The parts

provide reusable metal threads to attach plastics securely in compact electronic assemblies.

The inserts install permanently where designed into ABS, polycarbonate, and other plastic

substrates by pressing them into the host material using ultrasonic equipment or thermal

press. The new MSIA series of Aluminum alloy with different sizes and types offer light weight,

lead-free alternative.



Alternate Solutions


• Micro Standoff alternative solution:

The Micro Standoffs can be replaced by PEM® Type MSO4™ microPEM® Standoffs. The

parts enable components to be mounted and/or spaced in compact electronic assemblies,

especially suiting applications where space may be extremely limited for attachment

hardware. PennEngineering® can also offer MSO4s with different sizes and types to meet the

application requirement.



Alternate Solutions


• M1.4 SMT Micro Nut alternative solution:

The M1.4 SMT micro nut can be replaced by PEM® micro-SMTSO surface mount fasteners.

With micro-SMTSOs from PennEngineering® customer can benefit from all the advantages of

SMT technology even with the smallest components. Made of tin-plated steel, SMTSO can be

soldered together with other components using the reflow process. The miniature nuts are

available in thread sizes M1 to M1.6 and in lengths from 1 to 3 mm.



Alternate Solutions


• Φ1.90 X 3.4 Guide Pin alternative solution:

The Φ1.90 X 3.4 Guide Pin can be replaced by MPP™ microPEM® Self-clinching Pins.

Ideal for micro positioning and alignment applications, the Self-clinching Pins from

PennEngineering® can provide the MPPs with different sizes and types to meet the

application requirement.



Alternate Solutions


• Glued plastic-aluminum component alternative solution I:

On slide #7 the brass insert in the plastic boss by means of ultrasonic welding or heat staking

and the heat insertion is glued into the aluminum chassis. The below annular Snap Joints can

be used to replace the original design in order to improve efficiency and reduce cost.

Separable Design Inseparable Design



Alternate Solutions


• Glued plastic-aluminum component alternative solution II:

In same way, some positioning pins clinched into the aluminum chassis along with the edges

work as male snap fit elements (refer to Refer to YCHA-57222 Design

on slide #53). In this way the joints can be used to replace the original design for improving

efficiency and reducing cost.

Separable Design Inseparable Design



The Xiaomi Air 12 Notebook includes a total 169 fasteners throughout the device

assembly. The device was quite easy to disassemble despite the large number of fasteners and

components.

PennEngineering® is fully capable of making all of the fasteners shown on slides in

this teardown report. PennEngineering® can produce all of the fastening solutions used in this

notebook within our current manufacturing facilities. In addition to direct replacement and

perhaps some manufacturing and material substitution for functional and cost improvement,

some alternate fastening suggestions are presented for specific situations.

Significant cost savings can be achieved by replacing 38 pierces of M1 screws

illustrated on the slides #24, #37 to TS4™ microPEM® TackScrew™ Fasteners (refer to slide

#44), TA™/T4™ microPEM® TackPin® Fasteners (refer to slide #43) and TKA™/TK4™

microPEM® TackSert® Pins (refer to slide #42).

With TS4™ or TA™/T4™ or TKA™/TK4™ introduced into the keyboard joining, the

carbon steel made keyboard chassis (slides #24, #27, #38) can be removed. At the same time

the 38 pierces of M1 micro standoffs (refer to slide #27, #38) installed into the chassis can be

removed as well. Both parts replacement would result in substantial cost saving opportunities.

As far as it concerns the carbon steel chassis removal, the original guide pin and

standoffs installed into it can be replaced by the solutions showed on slide #51 with some

geometry and dimensions changed.

Additional savings could be achieved by using microPEM® FASTENERS in this

notebook.

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Conclusions and Summary



Guide pin

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Conclusions and Summary

Standoff

Refer to U-M2-1 Design Refer to YCHA-57222 Design
