Safety switch operating mechanism

1. A safety switch operating mechanism comprising:

an engagement mechanism mechanically linked to a plunger and arranged to receive an actuator such that insertion of the actuator into the engagement mechanism moves the plunger to a first position and removal of the actuator from the engagement mechanism moves the plunger to a second position; and

a resilient member which engages the plunger and resiliently resists movement of the plunger from the first position to the second position to resist removal of the actuator from the engagement mechanism, the resilient member being supported such that a biasing force of the resilient member is adjustable.

2. The safety switch operating mechanism of claim 1 wherein the resilient member comprises a planar member formed from a resilient material.

3. The safety switch operating mechanism of claim 2 wherein the planar member is constructed to flex about a fulcrum point located along the planar member.

4. The safety switch operating mechanism of claim 3 further comprising an adjustment member constructed to adjust the location of the fulcrum point.

5. The safety switch operating mechanism of claim 4 wherein the adjustment member comprises a block having at least one abutment point positioned proximate the planar member to define the fulcrum point.

6. The safety switch operating mechanism of claim 5 wherein the block includes a plurality of abutment points and orientation of the block relative to the planar member positions one of the plurality of abutment points proximate the planar member.

7. The safety switch operating mechanism of claim 5 wherein the block includes a plurality of faces and is rotatable relative to the planar member.

8. The safety switch operating mechanism of claim 5 wherein the block is invertable from a first position to a second position to allow the at least one abutment point to press against a first location and a second location of the planar member, respectively.

9. The safety switch operating mechanism of claim 1 wherein the resilient member is L-shaped.

10. The safety switch operating mechanism of claim 1 further comprising a recess formed in an end of the resilient member constructed to engage the plunger.

11. The safety switch operating mechanism of claim 1 wherein the engagement mechanism is a cam rotatably attached to the safety operating switch.

12. The safety switch operating mechanism of claim 11 , wherein the cam further comprises a cam surface constructed to push the plunger against the resilient member during removal of the actuator from the engagement mechanism.

13. A switch system comprising:

a housing;

a plunger slidably connected to the housing for opening and closing an electrical circuit;

a cam for moving the plunger between a first position and a second position; and

a resilient member for engaging the plunger and providing an adjustable bias force to the plunger to retain the plunger in one of the first position and the second position.

14. The switch assembly of claim 13 wherein the housing further comprises an inner housing and a lid for connecting to the inner housing and the resilient member is connected to the lid and the plunger is connected to the inner housing.

15. The switch assembly of claim 13 wherein the resilient member is a deflectable plate.

16. The switch assembly of claim 13 further comprising a block connectable to the housing in a plurality of positions and each position defines a bias force of the resilient member.

17. The switch assembly of claim 16 wherein the block is rotatably connected to the housing, the block being rotatable by at least one of manipulation of a selector knob and connecting the block to the housing in alternate positions.

18. A safety switch assembly comprising:

a plunger attached to a body;

a cam engaged with the plunger;

an actuator connected to the cam and constructed to move the cam between a first position and a second position;

a plate spring connected to the body and engaged with the plunger to retain a location of the cam; and

an adjuster engaged with the plate spring and constructed to adjust a length of a deflectable portion of the plate spring.

19. The safety switch assembly of claim 18 wherein the adjuster includes a plurality of sides and each of the plurality of sides has an abutment point that is a different distance from an end of the plate spring that engages the plunger.