brainstorming

[boscar]

Hello, I interpreted the solution with the clamp in the attached scheme.
If you compress the material with a clamp, will the compression not dilate the piece? (and consequently exit from tolerances)
the expansion is minimal, but also tolerance.

 

[boscar]

I have a doubt:
with a single pneumatic actuator, can you determine both the necessary position and the required force? (the force may vary between 2kn-20kn, while the position must be constant)

 

[Focus]

I have a doubt:
with a single pneumatic actuator, can you determine both the necessary position and the required force? (the force may vary between 2kn-20kn, while the position must be constant)

if you have to use the tire, with the actuator determines the force, for the position you must necessarily have an antagonist system (and also very rigid).

Hi.

 

[boscar]

the position value must be constant, but adjustable between 0 and 0.2 mm.
so the bar system must be adjustable somehow, is it smart to mount it on a pneumatic cylinder?
Are they solid enough?

 

[cacciatorino]

the position value must be constant, but adjustable between 0 and 0.2 mm.
so the bar system must be adjustable somehow, is it smart to mount it on a pneumatic cylinder?
Are they solid enough?

no, you have to put a ball recirculation guide or other (look at thk or nsk catalogs), on which to mount a plate that supports the roller. Then this plate will be pushed from the cylinder by a floating yoke. the adjustable bar should put it between the plate on the guide and a fixed reference, as much as possible close to the point where the forces apply (the best thing would be to have the strength resistant, the cylinder push and the line on a single axis, to reduce couples and moments that generate bending).
there are pneumatic actuators with integrated ball guide, but not for the sizes you need.

for the bar system, the adjustment can also be mounted on the fixed frame, it is not said that it should be on the mobile trolley. then you have to decide whether you want to make it adjustable by hand or through the machine control system. In the first case you just need a screw at a fine pace, in the second you need a motorized system.

 

[boscar]

Can you explain to me what you mean by "floating yoke"?
I think a linear guide pushed by the cylinder is not a good idea, you should mount the skates with absurd precision to get the required tolerance, right? are not better systems with screws without end or qlc like that?

 

[cacciatorino]

Can you explain to me what you mean by "floating yoke"?
I think a linear guide pushed by the cylinder is not a good idea, you should mount the skates with absurd precision to get the required tolerance, right? are not better systems with screws without end or qlc like that?

you are making confusion: a linear guide deals with the straightness of translation. the endless screw you need to turn the rotational motion of a motor into a translation, but you don't have to entrust to the screw the straightness of this translation.

the floating yoke: It is a saucer that puts itself in the head of the cylinder and contrasts with a flat surface obtained on the part to be pushed, but without being screwed or blocked in any way: this allows the cylinder not to suffer disallined thorns on the stem due to poor realization of the system.

 

[Mario SJPD]

but are you obliged to use the pneumatic cylinder? ? ?
the pattern of figure two hunters where you see both the screw and guides and skates could be a valid and complete solution if for example use of skates with brake....certain that the move is really minimal... .

 

[boscar]

we are obliged to use the pneumatic cylinder

 

[cacciatorino]

we are obliged to use the pneumatic cylinder

put the pneumoidraulic I had indicated to you, with small dimensions you have the push you need.

 

[boscar]

the system in fig 2 is great.
doubt is about the friction force. with the guides the ininerant will be to deal with with the force of friction, now if we correct the position gradually my fear is that everything remains firm as f friction is too high (let's move 1 cent! )
while the model cad of hunter placed at the beginning of this discussion is brilliant: no friction force caused by tracks and trolleys. you have to deal only with the attack forces present in the pneumatic cylinder. Now I don't know how big they are. we will have to analyze some catalogs of various manufacturers.

 

[boscar]

exact those tire cylinders are exactly what we need! :finger:

 

[cacciatorino]

the system in fig 2 is great.
doubt is about the friction force. with the guides the ininerant will be to deal with with the force of friction, now if we correct the position gradually my fear is that everything remains firm as f friction is too high (let's move 1 cent! )

with ball guides you don't have to worry about the first detachment friction. then, if the friction was 50 n (and I assure you it is far lower):

50/2000 = 0.025, i.e. 2.5%, inside the uncertainty field of a possible charge cell that you will insert between the cylinder and the cart if you have to measure the force.

The model I loaded at the beginning is not good because the linear guides are missing and the rollers are attached directly to the cylinder, which I told you is not good in case of relevant efforts as yours, in addition to the fact that with that mounting you can not control the aprallelism of the rollers.

 

[boscar]

reference to figure 2:
if you add a pneumatic cylinder that exercises the force on the cart, the screw with the snail is not stressed too much? Does it also lie the position or tend to advent? (with the joke the vine should not benefit, but suffers a force not indifferent! ! )

 

[boscar]

thanks to all x help and valuable advice! :finger: