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Letalis Sonus

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IBM Thinkpads use those multistrand flat ribbon cables to connect the screen.
Maybe the older ones do, I know for sure that the T4x and T60 series simply use reinforced foil cables, ribbon cables are only being used for the backlight due to its low pin count requirement.
 

Grench

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Maybe the older ones do, I know for sure that the T4x and T60 series simply use reinforced foil cables, ribbon cables are only being used for the backlight due to its low pin count requirement.

T60. Note the gigantic flat cable connecting the base to the screen just left of center. You don't normally notice it looking down at the machine on your desk.

s-l400.jpg

T400 lid & screen from a previous message above.
aI5XBaUg.jpg

Slightly bigger photo; still can't see anything. Derp.
 

Letalis Sonus

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Note the gigantic flat cable connecting the base to the screen just left of center.
It's a plastic covered foil cable, if I had a cam at hand I could open up my T60p for you. Here's some random replacement part picture of the whole T60 cable:

s506875824555543720_p285_i1_w500.jpeg


The short part to the left connects to the motherboard, it is being fixed by a small metal plate with a rather sharp edge that tends to damage the cable if you're not careful during disassembly.
 
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Grench

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It's a plastic covered foil cable, if I had a cam at hand I could open up my T60p for you. Here's some random replacement part picture of the whole T60 cable:

The short part to the left connects to the motherboard, it is being fixed by a small metal plate with a rather sharp edge that tends to damage the cable if you're not careful during disassembly.

Cool - I learned something new.
 

Grench

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I made a quick video explaining the new LCD Cables, as the dummy has arrived:
Thank you for the video! The solid copper dummy cable looks like it fits well. Do you have an estimates around when will you be receiving production samples?

One concern I have... It looks like the through-hinge portion of this is going to stay relatively static during screen/lid motion. That would mean that the mechanical motions would be carried just after the 90* directional changes. The cable will need slack to bend a bit in those areas instead of gaining slack by the coil roll contracting and enough extension to open the case to the hinge stops. This means that the minimal/maximum length for the cable is going to have less margin for error than the older 3x roll version.

You have probably taken all of that into account. Probably why you're prototyping the cable.

Looking forward to more!
 

EvilDragon

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Thank you for the video! The solid copper dummy cable looks like it fits well. Do you have an estimates around when will you be receiving production samples?

Not yet, but the last few times it took only 2 - 3 weeks.

One concern I have... It looks like the through-hinge portion of this is going to stay relatively static during screen/lid motion. That would mean that the mechanical motions would be carried just after the 90* directional changes. The cable will need slack to bend a bit in those areas instead of gaining slack by the coil roll contracting and enough extension to open the case to the hinge stops. This means that the minimal/maximum length for the cable is going to have less margin for error than the older 3x roll version.

Indeed, it does that :)
It makes a nice S-Curve near the mainboard when you open the lid. And there's enough space in the case for that.
 

levi

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The only thing that really concerns me looking at that video is having once read a book on material stresses, those sharp corners on the inside of the turns especially to the rolled bit look like kind of a bad idea. The behaviour of stresses explain that corners like that help to concentrate stresses, and is why aeroplane windows have rounded windows after IIRC it was the comet aeroplanes that came down with torn fuselages. If you could spare a few mm to round off those corners and still have it fitting in the case okay, that should be much less likely to start tearing.
 

EvilDragon

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The only thing that really concerns me looking at that video is having once read a book on material stresses, those sharp corners on the inside of the turns especially to the rolled bit look like kind of a bad idea. The behaviour of stresses explain that corners like that help to concentrate stresses, and is why aeroplane windows have rounded windows after IIRC it was the comet aeroplanes that came down with torn fuselages. If you could spare a few mm to round off those corners and still have it fitting in the case okay, that should be much less likely to start tearing.

The corners of the final cable will not be that sharp. Additionally, there's no real force where the corners are and there are not many traces there.
The corner which is most likely to tear does have the ground plane, so nothing will happen if a small tear develops there.
 

FaeMinx

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A concern I have:

A cable that is rolled many times through the hinge will have the physical movement of opening and closing the lid dispersed amongst the rolls... so the more rolls, the less overall stress on the cable every time you move the lid.

So I'm concerned that this new cable with no full rolls will actually concentrate the stress in one or two areas much much more with every movement.

Can anyone see what I'm getting at here?

Edit: rolling a piece of paper will stress the whole sheet... but that stress is dispersed over the whole sheet and the stress at any one point is relatively minor.
Bending a piece of paper will concentrate all that stress along the bend line.
 
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CFWhitman

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A concern I have:

A cable that is rolled many times through the hinge will have the physical movement of opening and closing the lid dispersed amongst the rolls... so the more rolls, the less overall stress on the cable every time you move the lid.

So I'm concerned that this new cable with no full rolls will actually concentrate the stress in one or two areas much much more with every movement.

Can anyone see what I'm getting at here?

Edit: rolling a piece of paper will stress the whole sheet... but that stress is dispersed over the whole sheet and the stress at any one point is relatively minor.
Bending a piece of paper will concentrate all that stress along the bend line.

I was thinking the same thing. There is a reason the cables are rolled 3 times.
 

EvilDragon

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Yes, as mentioned above, the cable now makes a nice S-Curve inside the case, outside of the hinge instead.
Not much stress applied there as well, as it's not moving THAT much (about 2mm)
 

Askarus

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You miss one point.
You need to get the whole thing including the connector through the small hinge, not only the wires.
 
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