Week 6:- Clamp Unit & Pin-Clamp Unit Design Challenge
AIM:
Design 3 Different types of Swivel Clamp Unit with Different Riser, Blade, and Clamp Arm for the given Car Panel. Maintain the stroke as 100mm and to Design a Pin-Clamp 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
SWIVEL CLAMP UNIT:
Clamp unit is a unit designed to hold /clamp the car panel with NC blocks/Mylars / rest by using a Swivel Clamp cylinders .
PARTS OF SWIVEL CLAMP UNIT:
Mylar/NC block/Finger: Finger is a movable part which is used to hold the car part from top against backup and they are usually mounted on the clamp arm.
L-block: L - shaped blocks are used to mount the finger to clamp arm, besides allowing adjustments for locator pin in two directions.
Shim/Spacer: They allow the finger to be moved to the correct xy locating and allow the customer to make adjustments to improve the quality of their product.
Blade: Part onto which the aforeside element are attached to.
Riser: L- shaped or T shaped tall block which regularly patterned holes to attach the above mentioned parts in modular way blade, spacer & Mylars. Riser is either a make part or standard part.
Stopper: The function of stopper is to restrict clamp going beyond the limit. Stopper is mounted between clamp arm and rest/blade. Stopper has two parts male and female, when this two parts meet they restrict motion.
