Week 5:- Rest Unit & Clamp Unit Design Challenge

Introduction-  A clamp is a type of fastener used to secure components to one another and stop them from moving in relation to one another. Clamps are most frequently employed in metallurgy, welding, and similar processes, as well as in carpentry cutting and gluing activities. Because they are simply irreplaceable, clamps are present in practically every workshop. When it comes to carrying out various specific jobs, their primary function is to substitute for the trustworthy extra pair of hands that every handyman needs. It is made up of a pneumatic clamp cylinder riser, a clamp arm, a finger, a back up/rest, and shims.

The 3-2-1 principle? 

Any three-dimensional body or part has three axes: x-axis, y-axis, and z-axis. Any of these axes can be used to move it, or any of its movement can be released to these three axes. The body can also spin around these axes at the same time. So the overall degree of freedom with which the body can move is six. It is necessary to constrain all degrees of freedom (DOF) when processing the body by arranging appropriate locating points and then clamping it in a fixed and required position. The essential technique for locating the points can be found below.

Locating a part to be machined involves mainly three steps: Supporting, Positioning, and Clamping.

Two main purposes of placing a part on a jig/fixture are:

• Accurately positioning the part at the required coordinates.
• Restricting all six degrees of movement so that the part cannot move.

An extensively used method for obtaining these objectives is the 3-2-1 principle or six degrees of freedom for part location.

 

The 3-2-1 method is a work-holding principle where three pins are located on the 1st principle plane, i.e., either XY, YZ, ZX. And two pins are located on the 2nd plane perpendicular to the 1st plane, and at last, one pin on the plane is mutually perpendicular to the 1st and 2nd planes. The aim is to constrain the movement of the work piece along all three axes.

 

Rest Unit & Clamp Unit Design

Rest Unit- 

It is used to rest the components/part on it during the operation. The shim and spacer are used to adjust rest block as per requirement. The riser is used to get the part at the required heights and generally it is used as standard part.