Pneumatic Grippers

The STD-G ("Gripper") series of products are a family of lightweight, high-moment capacity pneumatic grippers developed specifically for lift assists. The grippers are single acting (there is one stationary, and one moving jaw). These grippers are ideal for holding large, heavy (50-300 lbs) parts. The STD-G series of grippers are an excellent choice for lift assists (crane or manipulator hung end effectors).

Our grippers use high quality, re-circulating rail type linear bearings to support the moving jaw. Many competing solutions rely on telescoping sliders to support the moving jaw(s); these support substantially lower load at full stroke than when at minimum stroke. As a consequence these solutions cannot grip a part as far out from the gripper bodies as our grippers can.

All grippers ship standard with pilot operated check & flow control valves on both cylinder ports. The pilot operated (PO) check valves trap air in the event of a pneumatic failure (allowing the gripper jaws to maintain grip). The flow controls allow the opening and closing speed of the manipulator to be controlled.

The jaw moment is the bending load imposed on the linear rails inside of the gripper by the gripping force acting at some distance. The grip force for each model of gripper is listed in the tables below, as is the jaw moment rating referred to in the following formulas.

HORIZONTAL MOUNTING 

 JAW MOMENT = GRIP FORCE x L2 

 MOMENT 'A' = (LOAD x L1) + (JAW SELF WEIGHT x JAW CENTER OF GRAVITY (FROM CYLINDER)) 

JAW MOMENT = (GRIP FORCE+LOAD) x L2 

MOMENT 'B' = (LOAD x L1) + (JAW SELF WEIGHT x JAW CENTER OF GRAVITY (FROM CYLINDER))

If the gripper is to be used to lift a load vertically while facing the ground, and the part is held by friction only, then normally only the jaw moment needs to be calculated: JAW MOMENT = GRIP FORCE x L2. 

 If the load is held mechanically, the combined bending and normal loading on the linear bearing will need to be calculated.