Claims
- 1. A latch mechanism comprising:
a housing having a first end and a second end, said second end of said housing having an opening; a first sleeve rotatably supported by said housing; a slide supported for slidable movement relative to said first sleeve and for rotation with said first sleeve; a lock plug supported by said first sleeve, said lock plug being selectively rotatable between a locked position and an unlocked position relative to said first sleeve using a key, said lock plug moving said slide to an engaged position when said lock plug is in said unlocked position; a cam having at least one cam slot, said cam being rotatably supported within said housing, said cam being coupled to said slide so as to rotate between latched and unlatched positions in response to rotation of said first sleeve when said lock plug is in said unlocked position; means defining an edge supported in said housing; and a shaft positioned at least in part within said housing, said shaft extending through said opening in said second end of said housing, said shaft having at least one projection which is engaged at least to said at least one cam slot, said at least one cam slot being configured such that said shaft moves substantially rotationally as said cam moves from said unlatched position toward said latched position until said projection abuts said edge, thereafter said shaft moving substantially axially as said cam rotationally moves to said latched position, whereby said first sleeve rotates without rotating said cam when said lock plug is in said locked position to thereby prevent said latch mechanism from being defeated by application of excessive torque to the first sleeve.
- 2. The latch mechanism according to claim 1, wherein the closure member is a first closure member and cooperates with a second closure member, said housing has a flange at said first end thereof, said housing has an exterior surface having interrupted screw threads formed thereon for engagement by a mounting nut for securing said housing in place when said housing is mounted to one of the first closure member and the second closure member.
- 3. The latch mechanism according to claim 2, wherein said lock plug is of the type having a key access opening and an array of wafers that retract upon insertion of a key to thereby allow rotational motion of said lock plug under the control of a user, wherein said means defining an edge defines at least one motion control slot, said edge being part of said at least one motion control slot, and wherein said first sleeve includes means for retaining said lock plug in said locked position that is engaged by said array of wafers when said array of wafers are not retracted.
- 4. The latch mechanism according to claim 3, wherein said cam is substantially in the form of a cylindrical sleeve having a wall thickness, said cam slot extends through said wall thickness of said cam, said cam has a distal end and a proximal end relative to said first end of said housing, said cam has a pair of ears extending from said proximal end thereof, and said slide has a pair of notches which matingly receive said pair of ears of said cam to thereby allow said cam to move rotationally with said slide when said slide is in said engaged position.
- 5. The latch mechanism according to claim 4, wherein said cam slot has a proximal end closest to said proximal end of said cam and a distal end farthest from said proximal end of said cam, said cam has a longitudinal axis, and said cam slot has a pitch such that the axial distance, measured in a direction parallel to said longitudinal axis of said cam, between said cam slot and said proximal end of said cam increases in the clockwise direction, beginning at said proximal end of said cam slot, as viewed by a viewer facing said proximal end of said cam.
- 6. The latch mechanism according to claim 5, wherein said means defining an edge is a motion control sleeve having at least one motion control slot defined at least in part by said edge, said motion control sleeve has a longitudinal axis, said motion control slot has an axial slot portion extending substantially parallel to said longitudinal axis and a circumferential slot portion, said circumferential slot portion being continuous with said axial slot portion and extending from an end of said axial slot portion in a direction along a length of arc of a circle formed in a plane perpendicular to said longitudinal axis of said motion control sleeve.
- 7. A latch mechanism comprising:
a housing having a first end and a second end, said second end of said housing having an opening; means defining at least an edge within said housing in stationary relationship to said housing; a knob rotationally supported by said housing and having a pair of laterally extending wings, said knob being rotationally movable between a latched position and an unlatched position; a cam having at least one cam slot, said cam being rotatably supported within said housing, said cam being coupled to said knob so as to rotate in response to rotation of said knob; a shaft positioned at least in part within said housing, said shaft extending through said opening in said second end of said housing, said shaft having at least one projection which is engaged at least to said at least one cam slot, said at least one cam slot being configured such that said shaft moves substantially rotationally as said knob is moved from said unlatched position toward said latched position until said projection abuts said edge, thereafter said shaft moving substantially axially as said knob is rotationally moved to said latched position; a lock plug rotationally supported by said knob, said lock plug being movable between locked and unlocked positions; and a slide slidably supported by said knob, said slide moving between a retracted and an extended position responsive to rotation of said lock plug relative to said knob, said slide being in said extended position when said lock plug is in said locked position, and said slide engaging one of said housing and said means defining at least an edge to prevent rotation of said knob when said slide is in said extended position.
- 8. The latch mechanism according to claim 7, wherein the closure member is a first closure member and cooperates with a second closure member, said housing has a flange at said first end thereof, said housing has an exterior surface having interrupted screw threads formed thereon for engagement by a mounting nut for securing said housing in place when said housing is mounted to one of the first closure member and the second closure member.
- 9. The latch mechanism according to claim 8, wherein said lock plug is of the type having a key access opening and an array of wafers that retract upon insertion of a key to thereby allow rotational motion of said lock plug under the control of a user, wherein said means defining an edge defines at least one motion control slot, said edge being part of said at least one motion control slot, and wherein said knob has means for retaining said lock plug in said locked position that is engaged by said array of wafers when said array of wafers are not retracted.
- 10. The latch mechanism according to claim 9, wherein said cam is substantially in the form of a cylindrical sleeve having a wall thickness, said cam slot extends through said wall thickness of said cam, said cam has a distal end and a proximal end relative to said first end of said housing, said cam has a pair of ears extending from said proximal end thereof, and said knob is adapted to matingly receive said pair of ears of said cam to thereby allow said cam to move rotationally with said knob.
- 11. The latch mechanism according to claim 10, wherein said cam slot has a proximal end closest to said proximal end of said cam and a distal end farthest from said proximal end of said cam, said cam has a longitudinal axis, and said cam slot has a pitch such that the axial distance, measured in a direction parallel to said longitudinal axis of said cam, between said cam slot and said proximal end of said cam increases in the clockwise direction, beginning at said proximal end of said cam slot, as viewed by a viewer facing said proximal end of said cam.
- 12. The latch mechanism according to claim 11, wherein said means defining an edge is a motion control sleeve having at least one motion control slot, said motion control sleeve has a longitudinal axis, said motion control slot has an axial slot portion extending substantially parallel to said longitudinal axis and a circumferential slot portion, said circumferential slot portion being continuous with said axial slot portion and extending from an end of said axial slot portion in a direction along a length of arc of a circle formed in a plane perpendicular to said longitudinal axis of said motion control sleeve.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Divisional of U.S. patent application Ser. No. 09/850,969, filed on May 8, 2001, the entirety of which is incorporated herein by reference.
Divisions (1)
|
Number |
Date |
Country |
Parent |
09850969 |
May 2001 |
US |
Child |
10654148 |
Sep 2003 |
US |