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HANDBOOK OF MECHANICAL DESIGN 



Fig. 494. Fic_ 495 



Fig. 494.— a rocker-type switch such as used on polishers and portable sanders. It is not self-releasing and is 



now being replaced by plunger-operated dusttight switches such as shown in Fig. 498. 



Fig. 495. — Another style of mounting a commercial-type switch in a side handle. The switch is replaceable as a 



unit and is self-opening, as soon as the trigger is released; the return spring being shown dotted. 



Fig. 496. — In this switch mounting, the trigger actuates the switch by means of a lift rod attached to the back 

 of the trigger. A tension spring attached to the upper end of the lift rod and anchored to the lower end of the switch 

 plate pulls the switch open as soon as the trigger is released. If the locking pin is depressed when the trigger is pulled 

 back, it passes through the hole in the trigger which then cannot return to the open position. As soon as the trigger 

 is pressed, the locking pin is released, snaps back, and releases the trigger. 



