Electric switch

Claim 1

In an electrical switch including a housing containing at least one pair of stationary contacts, a plunger reciprocally mounted in said housing and carrying bridging contacts for engaging said stationary contacts in said housing when the plunger is moved from a normal position to a contact closing position, said housing containing a pair of cam rollers, each including a predetermined cam profile, a cam follower means integral with said plunger and engaged with said predetermined cam profiles to reciprocate said plunger between said normal and contact closing positions responsive to rotation of said cam rollers, wherein each of said cam rollers includes at least one radially inwardly extended slot adapted to receive the free end of an actuator inserted into said housing, thereby to effect rotation of said cam rollers responsive to continued inward movement of said actuator, the improvement comprising: a shaft supported in said housing and rotatable relative to the housing, said shaft having a non-circular cross-section over a medial portion of its length, and an integrally formed cylindrical extension at each of its ends, said shaft supporting said cam rollers for lateral, reciprocal sliding motion along said medial portion, between a normal roller position and a displaced position in which said rollers are relatively remote from one another; a biasing means for urging said cam rollers into said normal cam position; a first stop means integral with said plunger; and a second stop means on each of said cam rollers for engaging said first stop means to substantially prevent rotation of said cam rollers when in said normal cam position; means forming at least one housing opening through a wall of said housing, and a partitioning member for dividing each of said housing openings in two; and an actuating member having a base and a free end opposite the base, said actuating member adapted for insertion by its free end into said housing through any one of said housing openings, said actuating member having an actuating slot open to said free end, extended toward said base, and having a width corresponding to the thickness of said partitioning member to provide clearance between said actuator member and said partitioning member as said actuating member is inserted into said housing; said actuating member including a cam roller moving means at said free end for engaging said cam rollers as said actuating member is inserted, and for moving said rollers laterally away from said normal cam position responsive to further insertion of said actuating member, thereby to disengage said first and second stop means and free said cam wheels to rotate, said actuating member further including cam roller rotating means at said free end for engaging said radially inwardly extended slots to rotate said cam rollers.