Pushbutton switch with latching arrangement

Claim 1

An electrical switch comprising: first and second electrical contacts; a movable contact carrier supporting said first contact and movable between an on state in which said first contact conductively contacts said second contact and an off state in which said first contact is spaced from said second contact; a switching button movable between an on position and an off position; means connected between said button and said carrier for causing said carrier to move into its on state in response to movement of said button to its on position; a pivotally mounted two-armed blocking lever interposed between said button and said carrier, said lever having a first arm formed to engage said button when said button is in its on position, and a second arm engaged by said carrier as long as said carrier is not in its off state for causing said first arm to retain said button in its on position as long as said second arm is engaged by said carrier and for permitting said button to move to its off position when said carrier is in its off state, at least said second arm of said lever being elastically deformable, whereby the position of said button is indicative of the state of said carrier; and a spring biassing said button into its off position, wherein said button and said first arm of said lever have latch faces placed at a predetermined angle and arranged for cooperatively engaging so that a force exerted by said spring causes said button to exert on said lever a first torque in a direction to urge said latch face of said first arm of said lever out of engagement with said latch face of said button.