Toggle action clamping devices operate through a linkage system of levers and pivots. The fixed length levers, connected by pivot pins supply the action and clamping force. Toggle action clamping devices have an over centre lock point which is a fixed stop and linkage. Once in the over centre position, the toggle clamping device cannot move or unlock unless the linkage is moved. All types of toggle clamping devices have same action, just oriented differently.
The Toggle claming device Mechanism in a clamp has three functions.
- To multiply applied load at the handle into a high clamping force to hold the work piece.
- To create an over – centre lock to prevent the toggle clamping device from opening & releasing the work piece until opened by the operator.
- To rapidly open & close the toggle clamping device giving a maximum clearance in which to load & unload the work piece.