Spring loaded lock bolt

A lock for a retractable door that is moveable along a track may include a pin assembly coupled to the door and moveable with respect to the door from a retracted configuration to an extended configuration. A biasing element may bias the pin toward the extended configuration. A strike plate may be in the track and be configured to mate with the pin assembly. The door may be prevented from moving along the track when the pin assembly is mated with the strike plate.

BACKGROUND OF THE INVENTION

The present invention generally relates to a lock bolt for a door and, more particularly, to a spring loaded lock bolt for an overhead rolling door.

Overhead doors are commonly found on garages, as security grilles for retail stores, window sills, and other applications. Overhead doors can include roll up types, track types, swing up types, etc. These doors may move vertically along a track from a stored position to a closed position where the door substantially obstructs the doorway. It is preferable that these overhead doors have a lock to secure the doors in the closed position. When the lock is located at a midway point up the door, trespassers may apply a force to the lower end of the door bypassing the lock and creating an accessway enabling passage of a trespasser without fully opening the door. Furthermore, it is desirable in a retail setting to allow consumers to view merchandise through a security grille even when a retail store is closed. Such visibility is reduced when the lock is located at a midway point of the door. Thus, the lock is typically positioned at the lower end of the door.

Positioning the lock at the lower end of the door presents its own challenges. For example, the lock typically requires a user to first close the door and then bend down to activate the lock. However, users may not perform the locking procedure in this sequential order and may instead activate the lock before the door is fully closed and then close the door. This can cause unwanted wear and tear on the door as the locking element contacts a strike plate associated with the track.

Thus, a door with a lock element which can be locked either before or after the door is closed without damaging the door or associated door frame is desired.

BRIEF SUMMARY OF THE INVENTION

In one embodiment, a lock for a retractable door that is moveable along a track may comprise a pin assembly coupled to the door and moveable with respect to the door from a retracted configuration to an extended configuration; a biasing element configured to bias the pin assembly toward the extended configuration; and a strike plate in the track, the strike plate configured to mate with the pin assembly. The door may be prevented from moving along the track when the pin assembly is mated with the strike plate. The pin assembly may be coupled to the door and moveable with respect to the door, between a first position and a second position. The door may be lockable when the bolt is in the second position. The pin assembly may be adapted to move in concert with the bolt from the first position to the second position and move independently of the bolt from the retracted configuration to the extended configuration. The pin assembly may be adapted to move from the extended configuration to the retracted configuration as the door moves relative to the strike plate while the pin assembly is engaged with the strike plate.

In a further embodiment, the lock may comprise a locking element adapted to lock the bolt in the second position. The locking element may be adapted to attain the second position whether or not the pin is mated with the strike plate. The lock may be configured to cooperate with the door and the track such that when the bolt is in the second position, at least a portion of the pin assembly is disposed within the track and the door is moveable along the track when the pin assembly is within a free portion of the track and the door is not moveable along the track when the pin assembly is mated with the strike plate. The retractable door may include a housing configured to receive the pin assembly. In a further embodiment, the door may include a plug having an aperture configured to align the pin assembly with the strike plate, with the pin assembly configured to extend through the aperture. In a further embodiment, the door may comprise a stabilizer coupled to the pin assembly, the stabilizer aligning the pin assembly with the aperture. The stabilizer may be fixed to the pin assembly and the stabilizer may move as the pin assembly transfers between the contracted configuration and the extended configuration. The stabilizer may be adjacent the plug when the pin assembly is in the extended configuration and may be spaced from the plug when the pin assembly is in the contracted configuration. The biasing element may be a spring and the spring may be un-stressed when the pin assembly is in the extended configuration.

The lock may be configured to transition into a locked configuration when the bolt is in the second position and the pin assembly is in the extended configuration by the movement of the door along the track toward the strike plate such that the biasing element compresses when the pin assembly engages the strike plate and decompresses when the pin assembly is aligned with an opening in the strike plate such that the pin assembly extends into the opening. The lock may be configured to permit the door to be secured when the bolt is in the first position and the pin is in the extended configuration such that the biasing element remains uncompressed as the pin passes the strike plate and the bolt is moved to the second position such that the pin is within the opening. The strike plate may include an opening and the pin assembly mates with the strike plate when the pin assembly is within the opening. The strike plate may include a ramp portion extending away from the track, wherein the pin assembly is movable to the contracted configuration when the pin assembly engages the ramp. The strike plate may include a face with an opening and the pin assembly is configured to mate with the strike plate when a portion of the pin assembly is disposed within the opening. The strike plate may include a foot configured to be secured to a surface at a lower end of the track. The strike plate may include an offset portion between the face and the foot, the offset portion configured to engage the track.

In one embodiment, a method of securing a retractable door may comprise moving a bolt with respect to the retractable door from a first position to a second position, the bolt movably coupled to a pin assembly moveable with respect to the bolt from a retracted configuration to an extended configuration; locking the bolt in the second position; moving the door while the pin assembly is in the extended configuration; engaging a strike plate with the pin assembly, thereby transferring the pin assembly to the retracted configuration; and aligning the pin assembly the strike plate, thereby transferring the pin assembly to the extended configuration wherein the pin assembly is mated with the strike plate. The bolt may include a channel and the pin assembly may include an arrester within the channel configured to limit movement of the pin assembly with respect to the bolt. The moving the bolt step may include moving the pin assembly in concert with the bolt, and the engaging the strike plate step may include moving the pin assembly independently of the bolt. The pin assembly may move between the extended configuration and the retracted configuration after the locking step. The moving a bolt step may include moving the bolt and a second bolt with an actuator, the second bolt may move with respect to the door from a first position to a second position, the second bolt may be coupled to a second pin moveable with respect to the second bolt between an extended configuration and a retracted configuration with a second biasing element biasing the pin to the extended configuration.

A method of securing a retractable door may comprise providing a retractable door having a bolt moveable between a first position and a second position, a pin assembly moveable from a contracted configuration to an extended configuration, the door moveable along a track including a strike plate. The method may include closing the retractable door when the bolt is in the first position and the pin assembly is in the extended configuration such that the biasing element is uncompressed as the pin assembly passes the strike plate and the bolt is moved to the second position such that the pin assembly is mated with the strike plate. The method may include opening the door; and closing the door when the bolt is in the second position and the pin assembly is in the extended configuration such that the biasing element is compressed as the pin assembly passes the strike plate and decompresses when the pin assembly is aligned with the opening such that the assembly extends into the opening. In a further embodiment, the method includes retrofitting the bolt, pin assembly, and biasing element into an existing door by replacing a lock bar coupled to the existing door with the bolt, pin, and biasing element. The lock bar may be housed within a housing of the existing door and the method may further comprise accessing the lock bar within the housing prior to the replacing the lock bar step. The retrofitting step may be performed while the door is engaged with the track.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings in detail, wherein like reference numerals indicate like elements throughout, there is shown inFIGS. 1-11a lock, generally designated14, in accordance with an exemplary embodiment of the present invention.

Referring now toFIG. 1, the lock14may be attached to a door16by welding, adhesive, connectors (e.g. nails, screws, dowels) etc. The door16may be an overhead rolling door, a security grille, a track type door, a swing up type door, or any other type of device which serves to obstruct a doorway or opening. The lock14may secure the door16in position when it is in an open position, a closed position, or anywhere in between.

Turning now toFIG. 2, the lock14may include a housing18which may be coupled to the door16and have an internal cavity20to receive the internal components of the lock14. The housing18may be formed from the same material as the door16or may be formed of a different material having different properties than the door (e.g., heat resistant, higher material strength). In one embodiment, a moveable actuator22is within the cavity20and moves with respect to the housing18from a first position to a second position. In one embodiment, the actuator22moves toward an end of the housing as it moves from the first position to the second position. One type of actuator contemplated for use with the present device is described in U.S. Pat. No. 4,272,974, the disclosure of which is hereby incorporated herein by reference in its entirety. A locking element24(e.g., mortise cylinder) may be coupled to the actuator22to lock the actuator22in the second position. In one embodiment, a hole26is formed in the housing to allow access for a user to use a key (not shown) to lock the lock14. The actuator22may include a stud28adapted to be coupled to a pin assembly31having a bolt30(e.g., via threaded engagement, welding, ball and detent, bayonet lock). The pin assembly31may be moveable with respect to the housing18when the actuator22moves. In one embodiment, the pin assembly31includes a pin32coupled to the bolt30and the pin32is moveable with respect to the bolt30and housing18, as explained in greater detail below. A plug34may be at least partially positioned within the housing18. In one embodiment, a first portion36of the plug34may be within the housing18and a second portion38of the plug34may be within a track40(best seen inFIG. 7) to align the lock14with the track40. The housing18may include a removable access panel42which covers an opening (not shown) in the housing18. In one embodiment, the opening (not shown) may allow a user to repair, modify, or remove any of the internal components of the housing18while the door16and the housing18are engaged with the track40. For example, a user may remove the access panel42, detach an existing lock bar from the actuator22, and attach the pin assembly31without disengaging the housing18from the track40. The access panel42may be located on any side of the housing18and need not necessarily be located on a bottom surface thereof. However, locating the access panel42on the bottom surface may increase the security of the door by preventing unwanted persons from removing the access panel42to remove internal components and open the door.

Referring now toFIG. 3, the bolt30may include a cavity (not shown) that may be disposed within bolt30to receive the pin32. The bolt30may include a coupling44which can be attached to the stud28(e.g. via adhesive, welding, nut and bolt, hook and loop) on the actuator22such that movement of the actuator22causes movement of the bolt30from the first position to the second position. The coupling44may be attached to an end of the bolt30or a side thereof. The bolt30may be coaxial with the stud28when the coupling44is attached to an end of the bolt30. A channel46may be formed in the bolt30which is adapted to receive an arrestor48(best seen inFIG. 4). The channel46may extend through a sidewall of the bolt30or may be a recess which does not extend completely through the sidewall. The channel46could also be a protrusion, rail, etc. that engages a feature of the pin32to limit movement of the pin32with respect to the bolt30. In one embodiment, the bolt30and the pin32are both moveable along the same axis. In one embodiment, the bolt30may move between the first position and the second position when the locking element24is unlocked and is prevented from moving when the locking element is locked. In another embodiment, the pin32may move from the extended configuration to the contracted configuration when the locking element24is locked or when the locking element is unlocked.

Referring toFIG. 4, the pin32may include an aperture50to receive the arrestor48. Alternatively, the arrestor48may be coupled to the pin32via adhesive, welding, etc. In one embodiment, the arrestor48is fixedly secured to the pin32such that as the pin moves with respect to the bolt30, the arrestor48is moveable within the channel to contact the ends of the channel46to prevent further movement of the pin32. The interaction of the arrestor48and the channel46may also prevent rotational movement of the pin32with respect to the bolt30. For example, the pin32may have a cross-sectional shape other than round to prevent relative rotation between the bolt30and pin32. In another example, the channel46may be wider than the arrestor48to allow some rotational movement between the channel46and arrestor48. In one embodiment, the channel46extends along a path generally parallel to the bolt axis (not shown). In other embodiments, the channel46extends along a curved path which causes the pin32to rotate as the arrestor48moves along the curved path. The pin32may be moveable with respect to the bolt30from an extended configuration wherein the arrestor48contacts or is positioned toward a first end52of the channel46to a contracted configuration wherein the arrestor48contacts or is positioned toward a second end54of the channel46. The cavity (not shown) of the bolt30may be configured to receive a biasing element56(e.g. a spring, pressurized piston within a cylinder, electromagnets) which biases the pin32toward the extended configuration. A gasket (not shown) in the cavity may prevent debris from entering the cavity. In one embodiment, the biasing element56is a spring contacting a surface (e.g. an end, a rim) of the cavity and the arrestor48to bias the pin32toward the extended configuration. In one embodiment, the biasing element56is a spring exerting zero or minimal force on the arrestor48when the pin32is in the extended configuration. In another embodiment, the force exerted by the biasing element56is lower when the pin32is in the extended configuration than when the pin is in the contracted configuration. In another embodiment, the force exerted by the biasing element56on the pin32is substantial when the pin is in the extended configuration, but is still less than the force exerted by the biasing element on the pin when the pin is in the contracted configuration. The length of the channel46may be selectable to a desired amount of relative movement between the pin32and bolt30as desired.

Referring now toFIG. 5, the plug34may include an aperture58adapted to receive the pin32. The aperture58may allow at least a portion of the pin32to extend through the plug34to be engageable with a strike plate60in the track40as explained in greater detail below. In one embodiment, an end62of the pin32is flush with, or recessed with respect to, an end of the plug34(e.g., when the bolt30is in the first position and the pin32is in the extended configuration. In another embodiment, the end of the pin62may extend beyond the end of the plug34when the bolt30is in the first position and the pin32is in the extended configuration. In one embodiment, the housing includes a stabilizer means (e.g., a stabilizer64) for aligning the pin assembly with the aperture. The stabilizer64may be coupled to the pin32to at least partially assist in aligning the pin32with the aperture58. In one embodiment, the stabilizer64is fixed to the pin32and moves with the pin32relative to the plug34. The stabilizer64may assist in limiting movement of the pin32by contacting the plug34and preventing further movement of the pin when the stabilizer64is fixed to the pin32. In other embodiments, the stabilizer64is fixed to the housing18and the pin32moves through an opening (not shown) in the stabilizer64. In one embodiment, the stabilizer64is fixed to the housing18and the bolt30is adjacent or in contact with the stabilizer64when the bolt30is in the second position. The stabilizer64may be fixed to the access panel42and the stabilizer64may be replaced by disengaging it from the access panel42and interchanging a new one.

Turning now toFIG. 6, the lock14may include an activator66coupled to the actuator22to move the bolt30from the first position to the second position. In one embodiment, the bolt30is spaced from the end of the housing18by a first distance when the bolt30is in the first position and a second distance when in the second position, wherein the second distance is less than the first distance. The activator66may be a handle, crank, slide, rod, etc. that effectuates movement of the actuator22. The activator may move from a first setting66awhen the bolt30is in the first position to a second setting66bwhen the bolt30is in the second position. In one embodiment, the activator66may be removable from the housing18. In another embodiment, the activator66may be a switch connected to a motor to move the actuator22. In one embodiment, the locking element24may only be transitioned to the locked configuration when the activator66is in the second setting66band the bolt30is in the second position. In another embodiment, the locking element24may be transitioned to the locked configuration when the activator66is in either the first setting66a. The pin32may move in concert with the bolt30between the first position and the second position.

Referring now toFIG. 7, the door16may move within a track40when the door16is opened and closed. In one embodiment, the track40includes a seal feature such as a coupler68(e.g., a groove, recess) engageable with a portion of the plug34. In another embodiment, the coupler68receives a seal (e.g. silicone, rubber) to prevent or reduce the passage of gas through the doorway when the door16is closed. The strike plate60may be positioned within the track40. In one embodiment, the pin32may move along a free portion of the track40until the pin32contacts the strike plate60. In one embodiment, the strike plate60and track40are formed monolithically with each other. In another embodiment, the strike plate60and track40are separate elements that may be coupled together prior to the track40being installed in the doorway. In another embodiment, the strike plate60is coupled to the track40after the track is installed in the doorway. In one embodiment, the strike plate60is coupled to the track40by a screw70and washer72within a hole74(e.g. threaded hole). In another embodiment, the strike plate60is coupled to the track by welding, adhesive, nails, flexible connector (e.g. rope, wire), hook and loop (e.g. Velcro), ball and detent structure, or the like. The track40may include any number of strike plates60. In one embodiment, the track40includes more than one strike plate60which allows the door16to be secured at various positions along the track40. In one embodiment, the track40includes a plurality of strike plates60which are spaced from each other along the track40. In one embodiment, at least one of the plurality of strike plates60does not include a foot76. In one embodiment, any of the plurality of strike plates60which are spaced from a lower surface or floor do not need to include a foot76. In one embodiment, a track40is installed on each side of the doorway (not shown) and each track40includes a strike plate60. The strike plate60may include a foot76which contacts a boundary (e.g. ground, floor, windowsill) of the opening to be sealed by the door16. In one embodiment, the foot76is adjacent the ground or floor such that the door16is secured at the bottom of the track40. The strike plate60may include a back80which is adjacent to, or in contact with, an end82of the track40when the strike plate60is coupled to the track40. A slot78may be formed in the back80to receive a connector to secure the strike plate60to the track40. In one embodiment, the slot78is elongated and allows limited relative movement between the strike plate60and the track40after the screw70is coupled to the opening74. In another embodiment, the strike plate60includes more than one slot78. A ramp84may extend between the back80and a face86of the strike plate60. The ramp84may be straight, curved, stepped, etc. and extend outwardly away from the end82of the track40such that a rear surface88of the face86is spaced from the end82of the track40. In one embodiment, the face86is parallel to the end82. In another embodiment, the face84is oblique to the end82. An opening90may be formed in the face86which receives the pin32when the door16is closed as explained in greater detail below. In one embodiment, the opening90is slightly larger than the pin32to allow the pin32to enter the opening90but provide only limited movement of the pin32once it is within the opening90. In another embodiment, the opening90is elongated to allow easier alignment of the pin32within the opening90. The opening90may be circular, square, triangular, or any other desired shape provided that it is large enough to receive at least a portion of the pin32. In one embodiment, the strike plate60includes more than one opening90. In one embodiment, the strike plate60includes an offset portion91between face86and the foot76and the offset portion is configured to engage the track40. In one embodiment, the strike plate60does not include an opening90and instead, the pin32is secured in a recess (e.g., adjacent the offset portion91) between the face86and the foot76. The strike plate60may fit between the couplers68of the track40such that the strike plate60may be replaced after the track40has been installed, if desired. For example, the strike plate60could be removed from the track40and a strike plate60having a feature (e.g. opening, ramp, slot, foot) with a different parameter (e.g. size, shape, location) could be installed.

Referring toFIG. 8, a cross-sectional view depicting one foreseeable use of the lock14is shown. The track40and door16are not shown for ease of discussion but the strike plate60would be positioned in the track40and the door would be connected to the housing18as previously described. In the embodiment shown, the activator66(FIG. 6) is in the second setting66bsuch that the bolt30is in the second position when the end62of the pin32contacts the strike plate60. For example, a user may partially move the door16along the track40, move the activator66from the first setting66ato the second setting66b, and activate the locking element24prior to fully closing the door. The pin32may remain in the extended configuration and move in concert with the bolt30between the first position and the second position. The door16may then be moved further along the track40until the pin32contacts the strike plate60. In one embodiment, the end62of the pin32contacts the ramp84. In one embodiment, the end62of the pin32contacts the end82of the track40when the pin is in the extended configuration. In one embodiment, the end62of the pin32is frustoconical or chamfered to assist in moving the pin to the contracted configuration when the pin contacts the strike plate60. The stabilizer64may be spaced from the plug34when the bolt30is in the first position and adjacent the plug34when the bolt30is in the second position and the pin32is in the extended configuration.

Referring toFIG. 9, the pin32may move from the extended configuration (FIG. 8) to the contracted configuration (FIG. 9) as the door16continues to move along the track40and the pin32engages the ramp84of the strike plate60(e.g., when the door moves relative to the track40and the pin is disposed within the track40). The bolt30may remain in the second position while the pin32independently moves between the extended configuration and the contracted configuration. The biasing element56may be distorted (e.g. elongated, compressed) when the pin32is in the contracted configuration such that the biasing element56applies a force to the pin32. The stabilizer64may be spaced from the plug34when the bolt30is in the second position and the pin32is in the contracted configuration.

Referring toFIG. 10, the biasing element56may apply a force to the pin32and move the pin32(e.g. when the biasing element decompresses) to the extended configuration when the pin32is aligned with the opening90in the strike plate60. In one embodiment, the stabilizer64is adjacent the plug34when the pin32is within the opening90. In another embodiment, the stabilizer64is spaced from the plug34when the pin32is within the opening90. In one embodiment, a user activates the locking element24after the pin32is within the opening90. In another embodiment, the user activates the locking element24before the pin32is within the opening90. The pin32may move between the extended configuration and the contracted configuration even after the locking element24is locked because the pin32may move independently of the bolt30. The door16may be secured when the pin32is within the opening90and the locking element24is in the locked configuration. The user may unlock the door by unlocking the locking element24and moving the activator66to the first setting66a, thereby moving the bolt30to the first position. The pin32may move in concert with the bolt30between the second position and the first position, thereby disengaging the pin32from the strike plate60. The door16may then be moved along the track40. It is believed that adopting a pin32which may move from the extended configuration to the contracted configuration even after the activator66is moved and the locking element24is locked will reduce or eliminate damage to the track40, strike plate60, and lock14when a user locks the door prior to fully closing the door. In one embodiment, a bottom35of the plug34or the lock14may contact the foot76when the door16is in the extended configuration. In one embodiment, the foot76prevents further movement of the bottom35, and thus the door16, along the track40.

Referring toFIG. 11, the door may also be secured by moving the door along the track40with the bolt30in the first position. In one embodiment, the pin32is in the extended configuration and does not contact the ramp84as the door moves along the track40when the bolt30is in the first position. In other words, securing the door can occur without distorting the biasing element56. Thus, the door16can move along the track40without the biasing element56exerting a force on the pin32. The user may move the bolt30to the second position once the pin32is aligned with the opening90in the strike plate60such that the door is secured without the biasing element56exerting any force on the pin32. The user may move the locking element24to the locked configuration once the pin32is within the opening90(FIG. 10). In one embodiment, the user may move the door16along the track40with the bolt in the first position and secure the door without the biasing element56applying a force to the pin, unlock and open the door, then close the door with the bolt30in the second position such that the biasing element56exerts a force to move the pin32into the opening90as the door is secured.

Referring toFIG. 12, there is shown a second embodiment of the lock, generally designated94. The lock94is similar to the first embodiment of the lock except that the housing18may include a second bolt, pin, plug, etc. to engage a second strike plate in a second track (not shown). In one embodiment, the actuator22and activator66simultaneously move both bolts. In another embodiment, the bolts are moved independently of each other. A connecting rod92may couple the bolt30to the actuator22.

It will be appreciated by those skilled in the art that changes could be made to the exemplary embodiments shown and described above without departing from the broad inventive concepts thereof. It is understood, therefore, that this invention is not limited to the exemplary embodiments shown and described, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the claims. For example, specific features of the exemplary embodiments may or may not be part of the claimed invention and various features of the disclosed embodiments may be combined. The words “right”, “left”, “lower” and “upper” designate directions in the drawings to which reference is made. The words “inwardly” and “outwardly” refer to directions toward and away from, respectively, the geometric center of the lock. Unless specifically set forth herein, the terms “a”, “an” and “the” are not limited to one element but instead should be read as meaning “at least one”.

Further, to the extent that the methods of the present invention do not rely on the particular order of steps set forth herein, the particular order of the steps should not be construed as limitation on the claims. Any claims directed to the methods of the present invention should not be limited to the performance of their steps in the order written, and one skilled in the art can readily appreciate that the steps may be varied and still remain within the spirit and scope of the present invention.