Patent ID: 6360848
Filing Date: 2002-03-26
Classification: B66B,Y10T

Abstract:
A safety mechanism for use on a vertical reciprocating conveyor having a carriage mounted for movement between spaced vertical support columns between two or more levels, the safety mechanism comprising:a locking device positioned on the carriage and movable between an engaging position and a non-engaging position, wherein when the locking mechanism is in the engaging position, the carriage is prevented from moving relative to the vertical support columns; and a speed-sensing device positioned to detect the speed of movement of the carriage and operable to allow the locking device to move to the engaging position when the speed of the conveyor exceeds an upper speed limit, wherein the speed-sensing device comprises: a housing rotatable about an axis of rotation at a rotational speed directly proportional to the speed of movement of the carriage; a weighted shaft movable into and out of the housing as the housing rotates about the axis of rotation; and a stationary abutment positioned above the housing, wherein the weighted shaft contacts the abutment to prevent rotation of the housing and allow the locking device to rotate into the engaging position when the speed of the carriage exceeds the upper speed limit.