Mortise lock having internal auxiliary spring for lever
AssigneeEmhart Industries, Inc.
InventorGordon A. Alexander
Life of this patent
Estimating the term…
Abstract
A mortise lock operated by a two-directional inner knob and an outer lever handle has means within its case to limit rotation of the outer lever handle in one direction. An auxiliary hub spring also contained in the case and associated with the outer rollback hub provides additional yieldable resistance to rotation of the lever handle in said one direction to compensate for the movement of the lever handle which results from its radially offset center of gravity. The auxiliary hub spring also provides additional reactive torque to compensate for increased mechanical advantage attained through utilization of a lever handle.
Claims13
In a mortise latch having a case including opposing side walls, a latch bolt supported in the case for movement between projected and retracted positions relative thereto, a latch bolt spring normally biasing the latch bolt to its projected position, inner and outer hubs supported in the case between the side walls and journalled for independent coaxial angular movement relative to said case and each other, a linkage for retracting the latch bolt in response to angular movement of either of the hubs, and a first spring acting between the linkage and the case for yieldably resisting angular movement of either and both of the hubs, the improvement comprising means in said case for limiting angular movement of at least one of said hubs in one direction relative to said case, said one hub having a radially extending arm, a second spring in said case engaging and acting between said arm and said case for yieldably resisting angular movement of said one hub in the other direction, said second spring comprising a spiral spring having one end secured in fixed position relative to said case and another end engaging said one hub and biasing it in said one direction, and a spacer having one portion disposed between said inner and outer hubs and another portion extending outward beyond said hubs and disposed adjacent said spiral spring, said other portion retaining said spiral spring in an associated side portion of said case.
In a mortise latch having a case, a latch bolt supported in the case for movement between projected and retracted positions relative thereto, inner and outer hubs journalled in the case for independent angular movement relative to said case and each other, means for retracting the latch bolt in response to angular movement of either of the hubs, first biasing means yieldably resisting angular movement of either and both of the hubs, and stop works including a stop member movable generally toward and away from said hubs between locking and releasing positions relative to at least one of said hubs, the improvement comprising means in said case for limiting angular movement of at least one of said hubs in one direction relative to said case, second biasing means in said case for yieldably resisting angular movement of said one hub in the other direction, and a spacer partially disposed between and separating said inner and outer hubs and providing support for an associated portion of said movable stop member.
In a mortise latch having a case, a latch bolt supported in the case for movement between projected and retracted positions relative thereto, a latch bolt spring normally biasing the latch bolt to its projected position, inner and outer hubs journalled in the case for independent angular movement relative to said case and each other, a linkage for retracting the latch bolt in response to angular movement of either of the hubs, a first spring acting between the linkage and the case for yieldably resisting angular movement of either and both of the hubs, and a stop works including a stop member movable generally toward and away from said hubs between locking and releasing positions relative to at least one of said hubs, the improvement comprising means in said case for limiting angular movement of at least one of said hubs in one direction relative to said case, said one hub having a radially extending arm, a second spring in said case engaging and acting between said arm and said case for yieldably resisting angular movement of said one hub in the other direction, and a spacer partially disposed between and separating said inner and outer hubs and providing support for an associated portion of said movable stop member.
Dependencies are inferred from the claim text.