Week 6:- Clamp Unit & Pin-Clamp Unit Design Challenge

AIM

1) To design 3 different types of Swivel Clamp Unit with Different Riser, Blade, and Clamp Arm for the given Car Panel.

2) To design a Pin-Clamp Unit for the given Car Panel.

CLAMP UNIT

• A Clamp unit is usually designed to clamp or hold the car panel.
• Mylars such as Clamp mylars and Rest mylars is used in the clamping to hold the car panel.
• Clamp Mylar is usually operated by pneumatic cylinders.
• Another type of clamp unit is called a swivel type clamp unit and it is operated by swivel type Cylinder.
• In this unit, the clamp arm rotates with respect to the pivot point of the rotating blade.

DESIGN CONSIDERATIONS

• There should be at least 10 mm gap between the car panel and clamp unit to avoid damage to the panel.
• Pin Clamp unit should be used where panels or components are located for welding.
• Avoid clashing of clamping unit which may create problems during assembly.
• Clamp Plan should be followed strictly and no changes to be made in the clamp plan without any prior information.

SWIVEL CLAMPS

• The components involved in the swivel clamp type includes
• Clamp arm
• Mylars or Fingers
• Blade
• Swivel Cylinder
• Bush
• Stopper
• Locator
• Block
• Swivel clamps shall typically be designed with the center of the clamp cylinder, the center of the locator, and the center of the clamp arm on a common line.
• However, it is acceptable to offset the clamp point from the clamp cylinder to allow for improved access for welding and part load and unload.

COMPONENTS OF SWIVEL CLAMP

CLAMP ARM

• It is an arm connected to the clamping mylar and another end is attached to the clevis cylinder.
• It has two vertical plates on which one hole is provided which acts as a pivot point.
• When the cylinder arm retracts the arm rotates around the pivot point and the clamp mylar is operated.

SWIVEL CLAMP CYLINDER

• Clamp cylinder is used in swivel clamps which has a vertically moving arm with a fixed stroke length.
• This arm is attached to the clamp arm to actuate the clamping finger.

BLADE

• The blade is a part that acts a connecting member between all parts of the clamp unit.
• Different parts like clamp arm, cylinder, riser, etc. are attached to the blade.

STOPPER

• The stopper block restricts the motion of the clamp arm beyond the limit.
• The clamp arm is stopped at the exact required position with the help of the stopper block.

BUSH

• Bushes are used at the rotating components of pivot points.
• It acts as a friction beating lubricating with the grease and oil.
• It is press- filtered in the component.
• Over the time, due to friction these bushes get worn out and can be replaced with a new-ones instead of replacing the entire part.

Mylars or Fingers

• Mylars are the parts that hold the panel at the position and are directly in contact with the panel.
• The top mylar is called clamping mylar and the bottom mylar is called rest mylar.
• Mylars are also called as Fingers.

CLAMP MYLAR

REST MYLAR

PIN

• Pins are used for accurately locating the part to welded in an assembly.
• The holes in the part of the assembly are inserted on these pins.
• The pins constrain the degrees of freedom of the part of the fixture.
• The pins diameter has tighter tolerances than the diameter of the hole in the part.

SHIMS

• Shims are small parts of the various thickness.
• The shims are used to compensated for the difference due to the stack-up tolerance of the assembly which eventually results in the improper locating of the panel.
• Shims are used at L blocks, Pin retainer, risers to compensate the tolerance on the linear direction of the part.

RISER

• A riser is a part that is used to raise the height of the fixture.
• The riser is fixed to the base of the fixture and the blade is mounted on the riser.

ASEEMBLY OF THE UNITS

CLAMP UNIT 1

CLAMP UNIT 2

CLAMP UNIT 3

PIN CLAMP UNIT

CLAMP UNITS AND PIN UNIT ASSEMBLED IN A CAR PANEL

CONCLUSION

Thus the design of 3 different types of Swivel Clamp Unit with Different Riser, Blade, and Clamp Arm for the given Car Panel is completed and the pin Clamp unit is also designed for the given car panel as per design considerations.