Patent ID: 7178373

Claim:
A mortise lock comprising: a chassis adapted to be mounted in a mounting hole of a door, the chassis including at least one bolt; a handle assembly mounted to a side of the chassis, the handle assembly including: a spindle including a first end partially received in the chassis and operably connected to said at least one bolt such that rotation of the spindle causes retraction of said at least one bolt, the spindle further including a second end; and a handle including an end securely connected to the second end of the spindle to turn therewith; a sleeve including a first end and a second end, the first end of the sleeve being securely mounted around a portion of the first end of the spindle to turn therewith, the second end of the sleeve receiving the second end of the spindle and being securely connected to the end of the handle, the sleeve further including a longitudinal groove in an outer periphery thereof; and a trim for returning the handle assembly, the trim comprising: a spring seat including a plate mounted around the first end of the sleeve; a ring received in the spring seat, the ring including a body having a central hole and mounted around the first end of the sleeve, the ring further including a leg formed on a side of the body and extending in a direction parallel to a longitudinal direction of the spindle, a protrusion being formed on an inner periphery delimiting the central hole of the body, the protrusion being engaged in the longitudinal groove of the sleeve; a spring mounted on a side of the ring, the spring including a first end abutting against a side of the leg of the ring and a second end abutting against another side of the leg of the ring; and a lid for closing the spring seat; the end of the handle including an engaging hole, the sleeve including a longitudinal hole, the sleeve further including a positioning hole and a slot in the outer periphery of the sleeve, the slot being in communication with the longitudinal hole of the sleeve and aligned with the engaging hole of the handle, a tenon being mounted in the sleeve and including a first end received in the slot of the sleeve and a second end having a notch, the tenon further including an opening, a resilient member being substantially U-shaped and mounted in the sleeve, the resilient member including a first L-shaped leg pressing against an end edge delimiting the opening of the tenon, the resilient member further including a second L-shaped leg extending through the notch of the tenon into the positioning hole of the sleeve, the resilient member biasing the first end of the tenon into the engaging hole of the handle.