How a clutch works

3D Design Volume Model
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Hello

I have to design a multi-plate clutch with CATIA which I do not understand how to work. I am attaching the plan in question.

I know that a clutch allows you to transmit or not the rotation of the motor shaft to the gearbox. So there is a movement of translation of the piece 2.

According to the codes of the technical drawing, there is a gear on part 11 but on the BB section we see that there is only one tooth, I don't understand why? The same goes for section AA

I wonder what the purpose of Exhibit 9 is.

Thank you for your help and have a good weekend


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Good evening

Part 9 is a fork that pushes part 8 which will in turn push the discs shown in black (your clutch is multi-plate). It is the friction or not of the discs that allows the clutch to slip.

Teeth with a gear-like profile only serve to prevent the rotation of discs that actually serve as springs. It is not a spiral. The shape of the teeth allows for a certain amount of play. This function is in a way comparable to a key, except that a key never has a backlash. There are a multitude of systems  (as you can see on a multi-plate clutch as in your drawing). The discs are subject to very significant temperature variations, hence the expansion, hence the interest in allowing a very slight angular bypass.

Kind regards

 

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Hello

  Part 2 does not move in translation, it is stop 3 which by moving in translation  3/2 will drive part 9 in rotation "by pushing on the sloping surface".

 The braked nut 5 makes it possible to compensate for the gaps due to the wear of the discs and serves as a fixed plate on part 2.

At the level of sections B-B and A-A, the mixed lines serve as a normal representation for the grooves with just the drawing of a tooth to indicate its shape (nb. this drawing was already offered to students in the 90s, without CAD you might as well draw as few teeth as possible).

 

 

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Thank you very much for your answers and technical explanations, they helped me greatly!

I understand how it works better, indeed part 3 is mobile and part 9 compresses the discs which is much clearer. 

I'm surprised to learn that this drawing is so old! 

I have a few questions about details that I don't understand (excuse my ignorance I'm just starting out) 

Circle A: Are they really records like the ones at the bottom? 

Circle B: What is this misshapen ellipse? 

Circle C: I don't understand why it's not full given that since it's a cylinder it should be empty, and therefore with no material behind it? 

Cerce D: Is it the same as with the splines? A full key but not fully represented? 

On the AA section we see three parts, does this mean that there are three ranges? 

Thank you again for your help. 


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A: Yes, there are indeed disks like the ones at the bottom but they are not represented to facilitate the writing of the section reference (another trick to draw less)

For the AA section there are well 3 pieces 9 (levers / counterstops would be more suitable as a name to distinguish with the order fork not shown)

B:  it is an ellipse corresponding  to the intersection  of cylinder and plane (10-axis holes / passage groove in 2 of 9)

D: it is the representation of a key with  2 round  ends with a rectangular section (the hatched rectangle is a folded section of the key)

C: part 5 is an adjustment nut, the groove shown may be used as a socket for a wrench but more likely, given the similar teeth on part 6, positioning elements / graduations  for adjustment.

 

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Hello

For the ellipse and when you don't know or it's ambiguous, remember to always project a view on the other with straight lines. This is the basis of standard industrial design views.  /sites/default/files/from_ckeditor/2018-10-28_13_04_34-embrayage2_explication_projection_.jpg

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Sincerely a big thank you  to both of you! 

Thank you Maldoror for your answer, it helps me a lot. I understood almost everything, it is much more pleasant and at least I know what to do. 

Thank you Zozo for the idea of projections on the ellipse, I hadn't thought of it indeed. I had thought about it for the 10 axis, not for the ellipse. 

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Indeed, the basics of industrial design remain valid even in 3D and this can be seen with MEP.

Kind regards

PS: It's a bit like the story of a fish who prayed to be a bird and he was immediately exocet. :-)