Lock-out mechanism for empty/load changeover valve
AssigneeWestinghouse Air Brake Company
InventorStanley J. Pasek
Life of this patent
Estimating the term…
Abstract
A lock-out assembly having a latching mechanism by which means a plunger may be manually depressed and latched in a lock-out position in which a lock pin is pre-set by engagement with an actuator rod of an empty/load valve or the like, so that in response to axial extension of the actuator rod sufficient to align a locking groove in the actuator rod with the lock pin, locking engagement therebetween will occur to limit further axial extension of the actuator rod, without any further action on the part of the operator. Automatic disengagement of the lock pin from the locking groove of the actuator rod occurs in response to axial retraction of the actuator rod, by effecting disengagement of the latching mechanism to allow a return spring to reset the plunger.
Claims18
A lock-out assembly for limiting axial extension of an actuator rod from a retracted position thereof comprising:
- (a) a manually operable plunger having a reset position and a lock-out position, said plunger including a lock pin;
- (b) lost-motion means for connecting said lock pin to said plunger with relative axial movement therebetween;
- (c) a spring between said lock pin and said plunger, said lock pin projecting from one end of said plunger a predetermined distance when said relative axial movement therebetween is taken up;
- (d) detent means for latching said plunger in said lock-out position, the distance between the periphery of said actuator rod and said one end of said plunger in said lock-out position being less than said predetermined distance such that said spring is compressed to pre-set said lock pin under load for subsequent locking engagement with said actuator rod when said actuator rod is extended from said retracted position to a limit position to thereby restrict further extension of said actuator rod, said detent means being automatically disengaged in response to subsequent movement of said actuator rod toward rod toward said retracted position during said locking engagement of said lock pin with said stop means to unlatch said plunger;
- and
- (e) means for urging said plunger toward said reset position in which said one end of said plunger is displaced from said actuator rod a distance greater than said predetermined distance, whereby said lock pin through said plunger is withdrawn from said locking engagement with said actuator rod.
Dependencies are inferred from the claim text.