Limit switch rotary return mechanism

In a switch actuating mechanism having a linearly movable switch actuator for operating associated switch contacts, a switch spring operating against said linearly movable switch actuator, a rotary camshaft having an engagement with said linearly movable switch actuator to impart linear motion thereto in response to rotation of the camshaft, such camshaft having a flat against which a return spring force operates to center the camshaft in a neutral position, the combination of means including:

• a major return spring having a relatively large spring force acting upon said camshaft flat and urging said camshaft to said neutral position upon compression thereof;
• a minor return spring having a relatively small spring force acting serially with said major return spring upon said camshaft flat and also urging said camshaft to said neutral position upon compression thereof;
• stop means having at least a portion intermediate said major and minor return springs and adapted to limit compression of said minor return spring upon rotation of said camshaft away from said neutral position and following actuation of said switch contacts;
• and
• a return plunger resting upon said camshaft flat and having said major and minor return springs and said stop means guidingly disposed therein.