Design different type of swivel type clamp unit

Introduction:

Clamp unit is a unit designed to clamp or hold the car panel with help of NC block/ mylar/ rest by using pneumatic clamp cylinder.

mostly indian OEM used this type of clamp unit (swivel type clamp) in there fixtures.

Typical parts of Clevis clamp unit:

1]Clamp cylinder

In clevis clamp unit, swivel type cylinder is used. as shown in fig,

Pnumatic cylinder (sometimes known as air cylinder) are mechanicl devices which use the power of compressed gas to produce a force in a reciprocating linear motion.

Like hydraulic cylinder, something forces a piston to move in the desired direction. The piston is a disc or cylinder, and the piston rod transfers the force it develops to the object to be moved. Engineers sometimes prefer to use pneumatics because they are quieter, cleaner, and do not require large amounts of space for fluid storage.

Because the operating fluid is a gas, leakage from a pneumatic cylinder will not drip out and contaminate the surroundings, making pneumatics more desirable where cleanliness is a requirement.

Once actuated, compressed air enters into the tube at one end of the piston and imparts force on the piston. Consequently, the piston becomes displaced.

2]Finger

A finger is a NC block, which is mounted on clamp arm of the cylinder, and press the car panel towords the rest, so it holds the car panel.

Mylar: Called as Rest or Clamp block which is used for holding 2/3 BIW sheet metal parts.Mylars are also called NC blocks. In German language Mylar is called as counter stein. Mylars plays important role in the BIW welded assembly geometrical accuracy. Mylars are made of steel or in plastic material.

A rest is a NC block, which is fixed to the unit to support the car panel. Also it resist the clamping force of the finger and thus clamp the car panel.

3]Clamp Arm

A clamp arm is make part, it's made as per the position of clamp cylinder, stopper and shim. clamp arm made from hard material.

4]Stopper

The function of stopper is to restrict clamp going beyond the limt. stopper is mounted betwwn clam arm and rest or blade. stopeer has two part, when this two part meets they restrict motion.

5]Blade

Blade is make part, designed according to position of riser, clamp cylinder, clamp arm, rest mylar and stopper.

6]Riser

Riser is standard part, which provide height to the Pin unit, clamp unit as per requirments. Riser should have adequate strength so it can sustain under load of car panel, clamping cylinder, blades.

Clamp cylinder:

Clamp cylinder can order by giving follows input to manaufacturer

*Clamp cylinder used in my design is CKG1_B_63_100Y

Nomenclature :

CKG1 : Series of cylinder

B : Clevis width=19.5

63 : Bore size

100 : Cylinder Stroke in mm

Y : End Bracket i.e. Double Knuckle joint (M6 without tap)

Swivel Clamp Unit :

Factors should consider while designing clamp unit:

• Should use standers part as possible. i.e NAAMS
• There should be adequate space between cylinder and other part like riser, car panel. because cylinder moves or swing while opening and closing.

• Pin clamp unit is use where two panel or component are located and clamp for welding. as shown in fig no. 2
• Clamp make in such a way that it clamp two car panel at once.

• every clamp mylar/ NC block should have rest mylar/ unit.
• Clamp unit has shims in only one direction as shown in fig

.

• All parts should snap and butt properly to each other.
• make sure that parts of clamping unit are min 10 to 12 mm away from the car panel , so they not damage the car panel.
• Design tree should structured in way that make part on the top and followed standerd part.
• in this design dia 63 bore and 100 mm stroke size clevis clamp cylinder is used.

• The position of clevis joint pin will be in one line as shown fig.
• Avoid any clash, it will not rise issue at assembly.
• Product should design in such a way that it will easy to make,assemble and quality check.
• We should preferably usw quick acting clamps. the clampingmethod must notdamage our work piece. Clamp should open in such a way that clamp arm moves away from operator.
• There must be adequate clearance for loading and unloading. so that the process becomes fast and easy. the variation in size must be accepted.

• avoid sharpe edges and corner, they can harm operator and cause to the serious injury. provide chamfer or fillet to corner.
• Must possess suficient rigidity and robustness. it should not vibrate, as it can lead to unwanted movement of the work piece and tools.
• Must ensure total security in the operation.

Final Design of fixture:

Thus i designed 3 Different types of Clevis Clamp Unit with Different Riser, Blade and Clamp Arm for the given Car Panel.