Week 5:- Rest Unit & Clamp Unit Design Challenge

Week 5:- Rest Unit & Clamp Unit Design Challenge

Aim :-

Design 3 Different types of Power Clamp Unit with Different Riser, Blade and Clamp Arm for the given Car Panel.

Design 2 Different types of Rest Unit for the given Car Panel.

Introduction to Clamp unit and Rest unit :-

A Clamp is a device that is used to hold the part tightly, yet, firmly in the assembly, The clamp prevents any sought

of movement of the assembly in the fixture and ensures proper operation on the part without any distortion.

The clamp must be placed in such a way that it does not interpret the operation.

The clamp plan is the data provided by the customer. The clamp plan provides information on the location of pins,

rest units, Clamp units, Dumps, etc.

1) It gives the details of the exact position of the clamping locations in form of coordinates.

2) The clamp position in some cases will be in such a way that it might damage the tool, or very near to pin position.

3) In such cases, We should not take the decision to change the clamp plan without discussing it with the customer.

Fundamentls of design :-

3-2-1 principle: Our ultimate intention for using pin unit is to fix the work piece so that it does not deviate from

the position while the operation is being performed on it. For this reason we use 3-2-1 principle.

Every component we know has 6 degrees of freedom. They are listed below:

1. Translational motion along x-axis.
2. Translational motion along y-axis.
3. Translational motion along z-axis.
4. Rotational motion along x-axis.
5. Rotational motion along y-axis.
6. Rotational motion along y-axis..

In 3-2-1 principle we make use of locating pins in the given order to fix it on a fixture:

1) 3 pins are located on the bottom side of the component. These pins constrain the translational motion of the body in

z direction and rotational motion along x-axis and y-axis. Thus 3 degrees are restricted. But the body still can rotate

along z-axis and translate in x-axis and y-axis.

2) 2 pins are located on the back side of the component. These pins constrain the translational motion along x-axis and

rotational motion along z-axis. Thus we have constrained 5 degrees in total. But translation along y-axis is still possible.

3) 1 pin located on the adjacent side of the 2 pins we can constrain the last degree that is translation along y-axis.

Parts of a clamp unita and rest units are as follows

* Finger

A Finger is an NC Block, Which is mounted on the Clamp arm of the cylinder, and will press the car panels towards the

rest, so it holds the car panel.

*Rest

Rest is an NC block, which is fixed to the unit to support the car panel, also it resists the clamping force of the

finger, and thus clamps the car panel.

*Clamp Arm

A Clamp arm is a bought-out part, to which all the movable parts are fixed. In general, a clamp arm is a part of a

clamp cylinder.

*Clamp Cylinder

A Clamp Cylinder is a pneumatic device that works with pressurized air. The Clamp cylinder is used to open and close

the parts fixed to the clamp arm fixed to the clamp body. Clamp arms are generally bought out parts.

Shims

In general, a shim is a thin and often tapered or wedged piece of material, used to fill small gaps or

spaces between objects.

Shims are typically used in order to support, adjust for better fit, or provide a level surface.

Shims may also be used as spacers to fill gaps between parts subject to wear.

Shims are the small parts which comes with the thickness of 0.1mm, 0.2mm, 0.5mm, 1.0mm etc.

Blade

The plate which connects Riser to the Clamp cylinder is named Blade.

This plate plays an important role in building the unit. The plate can be of any shape,

But we need to keep in mind that the plate should be as compact as possible.

Riser

The part which is mounted on the base plate and holds a clamp or pin cylinder on it, is called Riser.

Riser can be Standard Part or manufactured part, it varies from project to project.

A riser can be a Single part or welded part. Standard risers also have various shapes and sizes.

Types of Clamp arms :-

Standard arm - Center type

Standard arm - single arm type

Standard arm - two arm type

Types of Clamping cyclinders :-

Power type cylinder

Overall length reduced by 49 mm max.

Depth reduced by 17.3 mm max

Swivel type cylinder

Pin Clamp Cylinder

Series CKU, Pin Shift Cylinder

Series CKQR, Plate Clamp Cylinder

Series M(D)UKA, Clamp Cylinder

CKGV, Pin Shift Cylinder

Swing type

Heavy-duty MK2 series

Possible to mount small auto switches on 4 surfaces

Auto mounting

Input data :-

Design of Clamp unit 1 :-

Design of Clamp unit 2 :-

Design of Clamp unit 3 :-

Design of Rest unit 1 :-

Design of Rest unit 2 :-

Assembly design :-