Allen-Bradley Company, LLC

Robert J Frey

Frank J Graninger

A mechanical latch attachment (20) for a control relay (21) includes a mechanical latch movement (77), a solenoid (49), and a pair of contact cartridges (33) that are disposed in a housing (25). The wear-resistant latch movement (77) has a latch (95) with teeth (103) on one end that are engaged by a pair of pivotable, hooked pawls (105). The latch (95) is coupled to an operating plunger (79) through a contact actuator (82). The operating plunger (79) can be coupled to a conventional control relay (21), which moves the plunger (79) upon the closing of its relay armature (30) to actuate the contacts (35, 36) in both the relay (21) and the attachment (20) and to move the latch (95) to a position where it is restricted by the pawls (105). The restriction of the latch (95) holds the relay armature (30) closed and the contacts (35, 36) actuated even though the relay (21) is deenergized. The solenoid (49) has an armature (62) that can be moved mchanically or electrically to release the latch (95) from the pawls (105). A high-compression spring (89) coupling the plunger to the contact actuator (82), protects the latch movement (77) from shock forces that might be encountered during shipment or abnormal handling. Relays with a mechanical latch attachment provide quiet operation and retain their operated state even in the event of a power failure.

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Greendale, WI, United States of America

Robert J Frey