Projectable Beyond Normal Biased Position Patents (Class 70/143)
  • Patent number: 11459796
    Abstract: A latch module for selectively engaging into a striking plate of door jamb, including at least a housing, a latch bolt, a guard bolt, and a stem for retracting the latch bolt is particularly versatile, safe and has low manufacturing costs, if the stem is movably supported relative to the latch bolt and if the stem has a block for entraining the latch bolt, if the stem reaches a first intermediate position while being moved from the stem's closed position towards the stem's open position.
    Type: Grant
    Filed: September 7, 2021
    Date of Patent: October 4, 2022
    Assignee: UHLMANN & ZACHER GmbH
    Inventor: Karl-Heinz Schmück
  • Patent number: 11339588
    Abstract: A lock indicator and a mechanical lock assembly, comprising: a switch; a transmitter coupled to a power source; and a bolt member moveable between a retracted position and an extended position with respect to the housing, wherein the switch is configured to engage the bolt member and is actuatable by the bolt member to determine the position of the bolt member, and the transmitter is configured to transmit a signal indicative of the position of the bolt member to a remote device.
    Type: Grant
    Filed: May 31, 2018
    Date of Patent: May 24, 2022
    Inventors: Ryan Bromley, Mark Cope
  • Patent number: 10100555
    Abstract: An arrangement for a lock is provided, comprising a stator, a rotor, which is rotatably arranged in the stator, and a set of elements arranged in the rotor for cooperating with the stator, which elements each have an opening and which elements are arranged successively in the longitudinal direction of the rotor and the openings of which together form a through hole for receiving a key, each of the elements being readjustably arranged, independently of each other, between a state which upon actuation is blocking and a state which upon the same actuation is releasing. The disclosure further concerns a key, which has a body along which a plurality of projections are arranged, the plurality of projections all being arranged in a common plane and the plurality of projections all having the same height and defining together the profile of the key.
    Type: Grant
    Filed: January 19, 2010
    Date of Patent: October 16, 2018
    Inventor: Bernt Adolfsson
  • Patent number: 8033147
    Abstract: An electronically controlled lock with a single throw acting as a passage lock and also as a deadbolt lock is provided by the invention. The lock is equipped with an electronic activation device on its exterior housing and a door lever on its internal housing. A user unlocks the door from outside by touching an electronic key against the electronic activation device. After the door is unlocked, the throw acts as a passage lock. The door can be locked internally by moving the door lever from a horizontal position upwardly to a vertical position.
    Type: Grant
    Filed: February 18, 2010
    Date of Patent: October 11, 2011
    Assignee: HandyTrac Systems, LLC
    Inventors: John Lie-Nielsen, Tibor Szenti
  • Patent number: 7698917
    Abstract: An electronically controlled lock with a single throw acting as a passage lock and also as a deadbolt lock is provided by the invention. The lock is equipped with an electronic activation device on its exterior housing and a door lever on its internal housing. A user unlocks the door from outside by touching an electronic key against the electronic activation device. After the door is unlocked, the throw acts as a passage lock. The door can be locked internally by moving the door lever from a horizontal position upwardly to a vertical position.
    Type: Grant
    Filed: March 6, 2006
    Date of Patent: April 20, 2010
    Assignee: Handytrac Systems, LLC
    Inventors: John Lie-Nielsen, Tibor Szenti
  • Patent number: 7325845
    Abstract: A latch assembly includes a plunger having a ramp and a lip, with a support member defining an opening through which the plunger extends. A support surface partially defines the opening and supports the plunger. The plunger is selectively movable between an extended position, in which the plunger protrudes a first distance from the opening, and a retracted position, in which the plunger protrudes a second distance from the opening, with the second distance being less than the first distance. In the extended position, the ramp and the lip are on a first side of the opening. In contrast, in the retracted position, the ramp and the lip are on a second side of the opening, with the lip engaging the support member to maintain the retracted position.
    Type: Grant
    Filed: January 4, 2005
    Date of Patent: February 5, 2008
    Assignee: General Motors Corporation
    Inventors: Andrew L. Bartos, Teresa U. Holiness, Robin Stevenson, Devadatta M. Kulkarni
  • Patent number: 6389855
    Abstract: In a locking device for a door, window or the like, having a main lock box, at least one supplementary lock box, and at least one drive rod connecting the supplementary lock boxes to the main lock box, better resistance to break-ins is attained in that the supplementary lock box has a latch bolt that can be retracted freely into the latching position, wherein the latch bolt is displaceable by a spring and/or by a gear past the normal latching position into its locking position.
    Type: Grant
    Filed: March 26, 1997
    Date of Patent: May 21, 2002
    Assignee: Gretsch-Unitas GmbH Baubeschlage
    Inventors: Walter Renz, Wolfgang Röger, Thomas Henzler
  • Patent number: 6257030
    Abstract: A multipoint lock assembly for securing a door that is hinged along one edge and that has a free, swingable edge opposite the hinged edge. The assembly includes a central latch and at least one remote latch vertically spaced therefrom along the free edge of the door. The retraction of all the latches is controlled by a central latch driving mechanism in response to a manual operation either of an exterior thumb-operated latch lever or of an interior doorknob. A deadbolt is also located proximate the central latch. The deadbolt is controlled either by an externally accessed cylinder lock in response to a manual insertion and rotation of a key or by a manual rotation of an interior-mounted thumb-turn. While the deadbolt is extended, the thumb-operated latch lever and the doorknob are inoperable. At least one of the latches includes a latch trigger. This is tripped when the door is closed, allowing the latch of which it is a part to assume a superextended position.
    Type: Grant
    Filed: June 9, 1999
    Date of Patent: July 10, 2001
    Assignee: Therma-Tru Corporation
    Inventors: Eugene R. Davis, III, Mark E. Riechmann
  • Patent number: 6247342
    Abstract: A lock with a latch bolt (41) has a translating part (65), which can be moved by a hub which can be turned by a button and/or key operation so that it controls an additional extension of the latch bolt (41) into a locking position and blocks the latch bolt in this locking position.
    Type: Grant
    Filed: May 12, 1999
    Date of Patent: June 19, 2001
    Assignee: Ferco International Ferrures et Serrures de Batiment
    Inventor: André Lilas
  • Patent number: 6151935
    Abstract: A deadbolt lock and a deadbolt which will extend automatically whenever a container is locked by virtue of a rigid portion of the container engaging a trigger element extending from the end face of the bolt and causing the release of an outer bolt portion is shown and described herein. The release of the outer bolt of the bolt assembly allows the outer bolt to project outwardly and to lock the container notwithstanding the fact that the bolt has not been reset by the operator of the lock. The bolt is self-contained and can be substituted into many existing lock mechanisms of the mechanical type and into some of the existing electronic dial combination locks, to provide the auto-locking enhancement.
    Type: Grant
    Filed: September 8, 1997
    Date of Patent: November 28, 2000
    Assignee: MAS-Hamilton Group
    Inventors: Walter R. Evans, James D. Hamilton, Kenneth H. Mimlitch
  • Patent number: 6032985
    Abstract: A latch device, which is especially adapted for an exit bar, incorporates a trigger assembly. When the latch device is retracted and released, as ordinarily occurs when the door is opened, the latch bolt is biased to an intermediate extended position. The trigger engages the rim of the strike plate which in turn releases a retainer arm and allows the latch bolt to project to an extended position within the strike thereby providing a latch function of high integrity.
    Type: Grant
    Filed: May 22, 1998
    Date of Patent: March 7, 2000
    Assignee: Harrow Products, Inc.
    Inventor: Ryan D. Cutter
  • Patent number: 5918916
    Abstract: An automatic door latch has a case and a bolt movable within the case between a fully extended position in which the bolt extends forwardly of the case and a partially extended position in which the bolt is positioned to contact a door strike. There is a plunger mounted on the bolt, with the bolt and plunger being relatively movable. A spring biases the bolt toward a fully extended position and a spring biases the plunger outwardly of the case. The plunger has a projection which limits outward movement of the plunger to a position in which its extension is the same as that of the bolt when it is in its partially extended position. There is a stop on the bolt movable toward and away from the case and there are projections on the case which coact with the bolt stop to limit bolt extension to its partially extended position.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: July 6, 1999
    Assignee: Schlage Lock Company
    Inventor: Pete Kajuch
  • Patent number: 5678432
    Abstract: An extended throw deadbolt lock including a housing having a face plate and an axial guide channel formed with a guide path having spaced apart locking seats. Angled transition surfaces extend toward each of the locking seats. A deadbolt member having a transverse locking member slot is mounted within the guide channel and a locking member, including a locking tab disposed in the guide path, is mounted within the locking member slot. A key cylinder having a rotatable cam is mounted on the housing. When the key cylinder is rotated, the cam engages the locking member to drive the locking tab from a locking seat and engage an abutment wall of the deadbolt member slot to drive the deadbolt member in the guide channel such that the tab moves in the guide path toward the other locking seat.
    Type: Grant
    Filed: July 20, 1995
    Date of Patent: October 21, 1997
    Assignee: Gregg Teskey
    Inventor: Gregg Teskey
  • Patent number: 5469723
    Abstract: A lock comprising a housing having an indoor side and an outdoor side; an axis passing through the housing from the indoor side to the outdoor side. A main bolt having a bolt portion and a latch portion, the main bolt being displaceable into and out of the housing. A double acting actuating mechanism coupled to the main bolt by the axis, the axis having a first pin to actuate the actuating mechanism and a second pin to actuate the actuating mechanism, the first pin and the second pin displacing the main bolt into and out of the housing. Locking means for preventing displacement of the main bolt. A combination hub being disposed in the housing, the combination hub releasing the locking means when a combination key is introduced into the combination hub. Means for limiting the displacement of the main bolt upon movement out of the housing such that only the latch portion is exposed out of the housing.
    Type: Grant
    Filed: November 25, 1992
    Date of Patent: November 28, 1995
    Inventors: Noel Litwin, Abraham I. Scherz
  • Patent number: 5368345
    Abstract: A multifunction hinged door lock with independently biased lever assemblies positioned one on each side of a door that drive the latch bolt of a latchbolt subassembly through the medium of a drive slide positioned for slidable movement in the sub assembly. The lever assemblies include at least one lock actuator such as a keyed cylinder to optionally displace at least one locking device between locked and unlocked configurations.The subassembly may optionally include an extended length bolt, a detent to restrain the bolt from fully extending prior to latching and optionally also include a detent to restrain the bolt from fully displacing prior to locking. The subassembly may optionally include an extended length bolt with a latching lever to assist initial latching.The subassembly may also optionally include a facility whereby inward displacement of the bolt during latching drives the locking device to the unlocked position if it were actuated to the locked position prior to latching.
    Type: Grant
    Filed: December 10, 1992
    Date of Patent: November 29, 1994
    Inventor: John R. Watts
  • Patent number: 5201200
    Abstract: An entry lock assembly comprising a dead bolt incrementally extendible by successive turns of a key, a slam bolt which is bodily reversible and blocked against retraction by the dead bolt when extended, and a lock face plate which is bodily reversible, for rehanding the lock.
    Type: Grant
    Filed: June 20, 1991
    Date of Patent: April 13, 1993
    Inventor: Peter Hauber
  • Patent number: 5044182
    Abstract: An automatic deadbolt and combined latch and automatic deadbolt is disclosed whereby a manually operable control on the inside of a door may be used to enable and disable the automatic extension of the latch bolt to a comparable deadbolt position upon the closing of the door. This allows one not having a key to the lock to set the manual control and then leave a premises, whereby upon the closing of the door the latch bolt will automatically extend to a deadbolt position, being retractable therefrom to again open the door either by the use of a key from outside, or by rotation of the inner latch control to withdraw the latch. Withdrawing the latch to open the door resets the deadbolt function in the embodiment described so that upon subsequent reclosing of the door, the automatic deadbolt function will not be reactivated unless specifically called for by control of the inside side of the lock mechanism.
    Type: Grant
    Filed: August 16, 1990
    Date of Patent: September 3, 1991
    Inventor: Clyde D. Totten
  • Patent number: 5020343
    Abstract: A lockset for a door comprising a latchbolt assembly movable between a partially extended latching position, a fully extended deadbolt position and a retracted position. A spindle extends through the latchbolt assembly in a direction transverse of the direction of movement of the bolt. The spindle is connected to the bolt for moving the bolt between its positions upon rotation of the spindle. An operating assembly includes a hand operator having a locking member therein, a first plate mounted for linear movement in a direction transverse to the axis of the spindle and having a pair of ears vertically spaced about and generally aligned with the longitudinal axis of the spindle. A pivotally mounted actuator member is movable in response to the hand operator and has first and second surfaces vertically spaced about and generally aligned with the longitudinal axis of the spindle and in engagement with the pair of ears such that pivotal movement of the actuator produces linear movement of the first plate.
    Type: Grant
    Filed: September 7, 1990
    Date of Patent: June 4, 1991
    Assignee: Emhart Industries, Inc.
    Inventors: LeRoy Hart, Theodore H. Miller, deceased
  • Patent number: 5009089
    Abstract: A double hook-bolt unit lock includes a lock barrel having a revolving rod connected thereto to cause a cam wheel assembly to move simultaneously so as to drive the stop keys of a stop frame assembly away from the upper notched portion of a brake frame assembly and to let the cam wheel assembly move the brake frame assembly rectilinearly via a lower notched portion of the frame assembly. By means of the push force from L-shaped guide slots of the side plates of a lockcasing and the guidance of oblique guide slots of a brake frame assembly, the two L-shaped bolts which are movably connected to the brake frame assembly are driven to smoothly into respective locking positions to lock the door.
    Type: Grant
    Filed: October 31, 1989
    Date of Patent: April 23, 1991
    Inventor: Emily M. Y. Lin
  • Patent number: 5003800
    Abstract: A remote control station and integrally installed electronic control circuit for use with a bolt and lock mechanism is set forth. In the lock, an air supply connected with first and second solenoid valves is incorporated and has a rod which extends to manipulate the bolt; bolt position is indicated by a switch means determining movement of the bolt to the deadlock position, and a door position switch is also incorporated. Various control signals are formed and are interlocked so that remote control or key switch control of the lock mechanism is obtained. It is implemented by providing control signals to the solenoid valves. They cause the bolt to move between the deadbolt and retracted positions, or to the intermediate slamlock position.
    Type: Grant
    Filed: July 17, 1989
    Date of Patent: April 2, 1991
    Assignee: Phelps-Tointon, Inc.
    Inventor: Leszek Bublewicz
  • Patent number: 4945737
    Abstract: A lockset for a door comprising a latch bolt assembly including a bolt movable between a partially extended latching position, a fully extending dead bolt position, and a retracted position. A spring biases the bolt toward its dead bolt position and a spindle extends through the latch assembly. The spindle is connected to the bolt to move the bolt between its positions upon rotation of the spindle. A mechanism is provided for holding the latch bolt in its latching position when the door is open and a mechanism responsive to the closing of the door is provided to move the latch bolt automatically into its dead bolt position.
    Type: Grant
    Filed: November 19, 1985
    Date of Patent: August 7, 1990
    Assignee: Emhart Industries, Inc.
    Inventor: Leroy Hart
  • Patent number: 4887442
    Abstract: An electronic lock includes a bolt having a fully extended position when a door is closed and a partially extended position when the door is open. The lockset is selectively placed in a locked state when the bolt is in its fully extended position. A switch is responsive to the position of the bolt and has a first operating position when the bolt is fully extended and a second operating position when the bolt is partially extended. A processor is responsive to the switch for preventing the selective locking of the bolt when the bolt is partially extended.
    Type: Grant
    Filed: September 27, 1988
    Date of Patent: December 19, 1989
    Assignee: Emhart Industries, Inc.
    Inventor: Gary E. Lavelle
  • Patent number: 4843850
    Abstract: The time release lock has three lock positions; open, a first locked position without time delay and a second locked position with time delay. The lock has a tongue which is withdrawn in the open position, extended to a certain extent in the first locked position and extended to a further extent in the second locked position. The lock can only be moved from the second locked position to the first locked position under influence of a timer.
    Type: Grant
    Filed: October 28, 1987
    Date of Patent: July 4, 1989
    Inventor: Jon D. C. McGregor
  • Patent number: 4788839
    Abstract: A tamper-resistant, reciprocating cylinder lock comprising a bolt and a bolt keeper having the capacity to prevent dislodgement of the bolt from engagement in its locked position with the keeper when the lock and keeper mechanism are under physical attack.
    Type: Grant
    Filed: February 16, 1983
    Date of Patent: December 6, 1988
    Assignee: Chapman Industries Corp.
    Inventor: Eugene L. Shuler
  • Patent number: 4739638
    Abstract: A deadlock includes a casing, a front knob and a rear knob respectively rotatably formed on the front and rear walls of the casing, and a slidable latch reciprocatively mounted in the casing as driven by either the front or rear knob, wherein the latch is formed a triangular locking tongue having two inclined surfaces so that the latch can be conveniently used in a bi-directional door when opening the door either outwards or inwards.
    Type: Grant
    Filed: February 3, 1987
    Date of Patent: April 26, 1988
    Inventor: George Lin
  • Patent number: 4691543
    Abstract: A deadlock with a locking bolt having a tongue that is displaceable from a latched position to an unlatched position, the lock including locking means to displace the tongue past the latched position to a locked position. The locking tongue is similarly curved on both sides so that, in use, it slides past a striker plate to the latched position in both right and left hand locking doors. A multi-point deadlock in which a center lock is coupled to at least one auxiliary lock via transmission mesans. The center lock having handles coupled to the latching tongue of the center lock and the transmission means so that downward movement of either handle causes the center lock to unlatch and upward movement of either handle from the horizontal drives the transmission means to effect locking of the auxiliary lock.
    Type: Grant
    Filed: March 25, 1986
    Date of Patent: September 8, 1987
    Inventor: John R. Watts
  • Patent number: 4679416
    Abstract: A lock mechanism includes a casing structure adapted to be mounted to one of a door and a door frame for cooperation with an apertured strike plate mounted to the other of the door and door frame. The lock mechanism further comprises a front plate for the casing structure with a pair of apertures therein and a latch bolt retractably mounted with respect to the casing structure and biased to an extended first position wherein a latching portion thereof extends from one of the front plate apertures for engagement with the strike plate aperture, and movable to a secnd retracted position. The latching portion of the latch bolt has a beveled leading surface located for engagement with the strike plate only when the latch bolt is moved a predetermined amount toward the retracted position.
    Type: Grant
    Filed: August 6, 1984
    Date of Patent: July 14, 1987
    Assignee: R. R. Brink Locking Systems, Inc.
    Inventor: Raymond V. Kambic
  • Patent number: 4656849
    Abstract: An improved deadbolt lockset is provided in which one of two different backset distances is facilitated in a single latch assembly. At least one planar side plate coupled to a deadbolt extension is provided and is slidably contained within a hollow latch case. Movement of the side plate determines the distance from the face plate of the assembly to the axis of an actuating assembly. The latch case includes slots formed therein for positioning the actuating assembly and to allow movement of the side plates.
    Type: Grant
    Filed: December 5, 1985
    Date of Patent: April 14, 1987
    Assignee: TRE Corporation
    Inventors: Anthony J. Rotondi, Richard O. Mullich, George F. Carabet
  • Patent number: 4648642
    Abstract: A chain door lock includes first part attached to a door adjacent the free edge of the door, a second part attached to the door jamb, and a chain attached to the second part and removably attached to the first part. The first part includes a horizontal spring chamber, a slide element within the spring chamber, a chain holder attached to the slide element, and a shock-absorbing coil spring between the slide element and the spring chamber. The second part includes a leaf spring. The chain is sufficiently long that the door may be partially opened without compressing either spring. The coil spring is sized to absorb a substantial impact, as from the body of a would-be intruder.
    Type: Grant
    Filed: April 15, 1985
    Date of Patent: March 10, 1987
    Inventor: John J. Berich
  • Patent number: 4641508
    Abstract: There is disclosed herein a lock mechanism having a lengthened bolt path which is compact and exhibits an increased mechanical efficiency. The lock includes a cylinder having a rotatable lock beard and a ring surrounding said cylinder for rotation upon engagement by the lock beard. A stop on the outer circumference of the ring engages a bolt notch formed in a bolt and tumbler plate. The lock beard, the ring and the bolt and tumbler plate lie in the same plane. The radius described by rotation of the lock beard is less than the distance between the rotational axis of the lock beard and the sides of the bolt notch.
    Type: Grant
    Filed: July 25, 1985
    Date of Patent: February 10, 1987
    Assignee: Zeiss Ikon Aktiengesellschaft
    Inventor: Dieter Gunther
  • Patent number: 4623175
    Abstract: A combined door latch and deadbolt is arranged to fit within the normal latch bolt openings provided in a pre-cut door. The solid combined longlatch and deadbolt is arranged to protrude at least one inch out from the door and into a striker plate which has a long angled depressor element against which the longlatch bears when the door is being swung closed. The longlatch is mounted in a cylinder which extends not only through the normal hole from the edge of the door, but also most of the way through the larger transverse hole provided in a pre-cut door, which is aligned with the usual position of the door handle. This relatively long cylinder provides the desired additional guidance for the longlatch with its increased travel as compared with conventional door latches.
    Type: Grant
    Filed: November 10, 1983
    Date of Patent: November 18, 1986
    Inventor: Charles Carroll
  • Patent number: 4594864
    Abstract: A lockset assembly which includes a bolt (12) movable between a partially extended latching position and a fully extended dead bolt position. When the bolt (12) is in the dead bolt position, the inside lever (10) can be used to retract the bolt. The outside operating assembly (27) is provided with a key operated lock cylinder (22) and the inside operating assembly (44) is provided with a turn button (26).
    Type: Grant
    Filed: September 30, 1983
    Date of Patent: June 17, 1986
    Assignee: Emhart Industries, Inc.
    Inventor: Leroy Hart
  • Patent number: 4333324
    Abstract: One part of a key-in-knob lock set functions in a normal manner such that when the lock set is unlocked, either the outside or inside knob can be manipulated to open the door by withdrawing the latch bolt from a normal spring latch extended position. When, instead, the lock set is locked, the latch bolt is extended an exceptionally long distance into the frame to a dead bolt position. Extension and retraction of the latch bolt to and from dead bolt position is accomplished by manipulation of a main cam through the agency of a key in the outside or a turn button on the inside.For withdrawing the latch bolt from the normal spring latch extended position, an escutcheon housing for the outside knob or a corresponding escutcheon housing for the inside knob serves, by moving transversely of the axis of rotation of the knob, to rotate a radially extending tooth-like element on the spindle which, acting through the main cam, withdraws the latch bolt.
    Type: Grant
    Filed: June 23, 1980
    Date of Patent: June 8, 1982
    Assignee: Norris Industries, Inc.
    Inventors: Hagen Dietrich, William J. Fane
  • Patent number: 4255953
    Abstract: One part of a key-in-knob lock set functions in a normal manner such that when the lock set is unlocked, either the outside or inside knob can be manipulated to open the door by withdrawing the latch bolt from a normal spring latch extended position. When, instead, the lock set is locked, the latch bolt is extended an exceptionally long distance into the frame to a dead bolt position. Extension and retraction of the latch bolt to and from dead bolt position is accomplished by manipulation of a main cam through the agency of a key in the outside knob or a turn button on the inside knob.For withdrawing the latch bolt from the normal spring latch extended position an escutcheon housing for the outside knob or a corresponding escutcheon housing for the inside knob serves, by moving transversely of the axis of rotation of the knob, to rotate a radially extending finger on the spindle which, acting through the main cam, withdraws the latch bolt.
    Type: Grant
    Filed: May 2, 1979
    Date of Patent: March 17, 1981
    Assignee: Norris Industries, Inc.
    Inventors: Hagen Dietrich, William J. Fane
  • Patent number: 3933380
    Abstract: A lock mechanism having a casing through which a spring-biased bolt is slidably movable, the bolt having an end which can be normally extended for a relatively short distance beyond the casing to assume a so-called "latching" position. A slidable sensing bar is arranged alongside of the bolt and in sliding contact therewith and the sensing bar is spring-biased so that it normally projects out of the casing for a distance co-extensive with the bolt while the bolt is either retracted or is in its latching position. A roller carried by the bolt is interposed between the bolt and the sensing bar and is confined in the casing in such a manner that while it rests upon a cam portion of the sensing bar, its bodily movement in the casing will be limited by a stop located therein and the bolt and the sensing bar will be maintained together in either the fully retracted position of the bolt or in its latching position.
    Type: Grant
    Filed: October 21, 1974
    Date of Patent: January 20, 1976
    Inventor: John F. Wellekens
  • Patent number: 3930677
    Abstract: A latch mechanism for a closure member that has a lever arrangement for connecting a main bolt to an auxiliary bolt. The two bolts are retractable together against the bias of a spring which acts through the lever arrangement to provide increased extension of the main bolt when the auxiliary bolt is maintained in a retracted position.
    Type: Grant
    Filed: November 21, 1974
    Date of Patent: January 6, 1976
    Assignee: General Motors Corporation
    Inventor: Lyn C. Hollis