Week 5:- Rest Unit & Clamp Unit Design Challenge

AIM

TO Design 3 Different types of Power Clamp Unit with Different Riser, Blade and Clamp Arm for the given Car Panel AND TO Design 2 Different types of Rest Unit for the given Car Panel.

INTRODUCTION

The clamp unit consists of various parts as clamp arm, rest Mylar, blade, raiser, pneumatic cylinder and some included to hold the car panel or the work piece.The pneumatic cylinder stroke length may vary depending upon the opening and closing angle.

Clamp unit :

It is used to clamp the car panel to achieve the 3-2-1principal.

The clamping force should be to a particular level.It should not be very high(it may create damage to work piece) and very low(it may not hold the work piece sufficiently so it will violate the 3-2-1 principal).

So it is important to consider the clamping force while designing.

Rest unit:

A rest unit is used to support the car panel, Also is resists clamping force of the finger with the help of rest Mylars & thus clamp the car panel.

Rest unit consists of rest Mylars, shim packs, riser.

Holding force should be considered while designing a rest unit.

Mostly to avoid excess part, to reduce the weight & reduce the cost of the fixture the rest unit is combined with the clamp unit.

Below figure shows the combination of the clamps & rest unit which have been designed in this project by considering the basic principles of clap & rest unit design.

3-2-1 PRINCIPAL:

Locating of a part to be machined is a three-step process:
1. Supporting
2. Locating (positioning)
3. Holding (clamping)

The Locating Process: Degrees of Freedom

In order to completely specify the position in space of a three-dimensional

object (such as the cube that’s shown), we refer to six coordinates:

Translational position along the X-axis

Translational position along the Y-axis

Translational position along the Z-axis

Rotational position about the X-axis

Rotational position about the Y-axis

Rotational position about the Z-axis