Abstract: A hand repairable plunger lock key includes a hollow body in which is hand inserted or removed a pair of springs and a cartridge which tends to periodically wear out and require replacement. A cap is threaded to the body and is manually removed or attached without tools. A key operating cam has a pin which is releasably secured to a mating slot in the cartridge operating shaft which protrudes from the cap. The body and cap are resiliently displaced a distance sufficient for the slot to be engaged or disengaged with the cam pin. Once engaged, the body and cap are released to normally bias the pin to the shaft slot via springs in the key used to bias the cam against the cap.

Abstract: A fractional-rotation latching system with retrofit capability which includes, in its most preferred embodiment with reference to an example vending machine environment, a T-handle housing to be connected to a vending machine door, a T-handle designed to be nested at least partially within the T-handle housing, a key-operated cylinder lock contained within the T-handle and including a radial lock bolt, a fractional-rotation post member connected to the T-handle, corresponding receiving assembly connected to the vending machine frame for receiving the post member, thereby creating a link sufficient to secure the vending machine door to the vending machine frame, a rotation limitation assembly connected to the post member which includes a cam washer and a flanged washer located within the T-handle housing, and a guide block interposed between the post member and the T-handle to secure a continuously engaging connection between the post member and the T-handle and to limit axial movement between the T-handle and

Abstract: A Latching System comprises a notched post assembly, a post gripping assembly and a handle assembly, and, in preferred embodiments, a lock assembly associated with the handle assembly, wherein the notched post assembly is comprised of an elongated post formed at one end with at least two opposing, axially extending rows of notches or teeth and alternately disposed smooth surfaces and the post gripping assembly comprises a channel for accepting the notched end of the post and comprises movable cam elements which cooperate with the notches of the post to effect the primary latching function of the system; and wherein the unlatching of the post from the channel is accomplished by rotating the post to disengage the notches and the cam elements. A pick-resisting improvement to the cylinder lock assembly includes facial piece defined with a plurality of knobs protruding partly into the key entry passage of the lock assembly.

Abstract: A device for locking a container attached to two leaves of a container door. The device consists of two pieces, one attached to each leaf of the door. A locking bar is inserted through a set of rings, attached to the two pieces, that align when the container doors are closed. A feature of the device allows the relative adjustment of the rings. In one embodiment, a separate metal plate replaces one of the rings and secures the control levers of the vertical bars of the container.

Abstract: A door latch comprises a post and collar gripping and release mechanism cooperatively mounted to the door and door frame of a vending machine, cabinet, or the like, to provide an initial latching function in the form of a frictional gripping of the post by the collar, and further comprises a lock assembly associated with the post and collar mechanism to provide a primary locking function and to effect release of the latching function.

Abstract: A locking apparatus is operative to selectively prevent the folding of a wheelchair of the type having a pair of centrally pivoted cross braces under the wheelchair seat. A bracket member is provided at each end of a pin which is adapted to constitute the pivot for the cross braces. An elongate bar is hinged at one end to one of the brackets and is adapted to be swung into a position between the cross braces so as to obstruct folding. A locking device operates between the other end of the bar and the other of the brackets for selectively retaining the bar in obstructing position.

Abstract: The invention relates to an anti-theft device for spectacle frames, which consists of an elongate body (10, 11) to be clamped to one bow of the spectacle frame, said body comprising a sleeve (10) open at one end thereof and having a transverse aperture (12) to receive therein the bow. Furthermore, said body is provided with a sensor (33) affecting an anti-theft system. A slide (15) displaceable longitudinally of the sleeve can be adjusted for engagement and disengagement of the bow by a screw (18) locked against axial displacement in the sleeve. The screw can be operated manually when the anti-theft device is to be mounted and demounted by a special tool only, which can be inserted into the sleeve through the open end thereof to engage an engagement element (22) of the screw located inside the sleeve.

Abstract: An improved shackleless padlock which engages and secures a conventional hasp configuration by use of a pop-out lock mechanism which has a non-rotating cylindrically extending lock bolt that engages the hasp staple. The pop-out lock mechanism is created by use of a spring to bias the lock mechanism outwardly from the padlock body when the lock contained within the lock shell is in a locked position, the lock mechanism is pushed inwardly into the padlock body until it latches into a fixed position and the lock bolt consequently engages the hasp staple. Strength is added to the die cast metal alloy construction of the padlock body by use of vertical and horizontal hardened, force-fit pins embedded in the padlock body. Also, a material saving well is formed in the top face of the padlock body which may also be utilized for displaying a nameplate.

Abstract: A locking device for locking instruments such as boat sonar units to their mounting brackets includes a key tumbler housing and a casing surrounding the key tumbler housing so that the tumbler housing rotates within the casing when a key is inserted in the tumbler housing, and remains locked in a fixed position when the key is removed. A threaded stud unit is connected to a rearward end of the tumbler housing which engages with a threaded hole in the instrument body when the tumbler housing is turned with the key. The instrument is locked to the bracket by passing the threaded stud through an opening in the bracket and engaging the stud within the threaded hole in the instrument body. A stop member is provided on a rear face of the casing which seats within the bracket opening, so that when the key is removed from the tumbler housing the locking device cannot be unscrewed from the instrument.

Abstract: A barrel lock and a key for locking and unlocking the barrel lock. The lock has a hollow barrel with a spring loaded plunger that reciprocates within the bore of the barrel. A recess is provided in an axial blind bore formed in the rear end of the plunger, the recess defining a gripping surface for unlocking the barrel lock. A spring loaded baffle washer having a key central aperture is positioned within the barrel bore rearwardly of the plunger. The baffle washer limits access to the plunger and prevents unauthorized unlocking of the barrel lock.The key has elongated outer expanding fingers and an inner coaxially arranged expander rod. The expanding fingers are sized and shaped so that they can pass entirely through the key central aperture of the baffle washer. When the key is fully inserted into the lock and the key handle is operated, the expanding fingers radially expand and press against the gripping surface in the blind bore.

Abstract: A lock assembly includes a lock body having a hole longitudinally therethrough, a plunger arranged longitudinally in the hole, a single strong spring coiled around the plunger and arranged longitudinally in the hole inside the lock body for returning the plunger to an open position, a key for turning the plunger to a closed position, and a plate for receiving the plunger in the closed position. A hole in the head portion of the plunger and a hollowed end of the key have matching hexagonal cross-sections for engagement with each other. A first roll pin is seated in the hole in the head portion and guides the hollowed end of the key into the hole. A second roll pin is inserted crossways into another hole in a middle body portion of the plunger for retaining the plunger in the open position.

Abstract: A latching system comprises a notched post assembly, a post gripping assembly and a handle assembly, and, in preferred embodiments, a lock assembly associated with the handle assembly, wherein the notched post assembly is comprised of an elongated post formed at one end with at least two opposing, axially extending rows of notches or teeth and alternately disposed smooth surfaces and the post gripping assembly comprises a channel for accepting the notched end of the post and comprises movable cam elements which cooperate with the notches of the post to effect the primary latching function of the system; and wherein the unlatching of the post from the channel is accomplished by rotating the post to disengage the notches and the cam elements. A pick-resisting improvement to the cylinder lock assembly includes facial piece defined with a plurality of knobs protruding partly into the key entry passage of the lock assembly.

Abstract: A high security post lock according to the invention includes a hardened shell having a head member at one end thereof and an eccentric locking cam rotatably mounted at the other end. The lock is adapted to be inserted through an opening passing through a door frame and a door to secure the door. In a first or open position, the circumference of the cam is coextensive with the circumference of the shell, so that the lock can be inserted into and withdrawn from the door. In a second or locked position, the locking cam projects outwardly from the shell to prevent withdrawal of the lock and thus secure the door. Movement of the cam is limited by a pin and groove arrangement.

Abstract: A lock assembly for preventing unauthorized opening of a utility meter box cover. The assembly includes a lock housing detachably mounted to a box side wall by a fastener which is accessible from the box interior. A post is shiftable in a passageway extending through the lock housing between an operative position overlapping the cover and a retracted position clear of the cover. A barrel lock is removably received in the lock housing to prevent shifting of the post from its operative to its inoperative position.

Abstract: An improved trailer hitch is disclosed for coupling a towing vehicle and a trailer. The invention is suitable for accommodating both ball and socket-type couplings and ring and pintle-type couplings. The integral body of the trailer hitch has the known elements of a rear mount for attaching the body to a towing vehicle, a ball housing with a bore for mounting a removable ball stud, a plate for mating with the attachment means of a towed vehicle, and a passage for connecting a latching arm. The improvement comprises four elements. First, the latching arm has a head, having a front face and a rear face, and a pair of substantially parallel legs integrally attached to opposite sides of the head and extending beyond the faces of the head. Each leg has an aperture for mating with the passage of the integral body and engaging a pin. Second, to prevent rotation of the latching arm, a notch on the integral body seats the rear face of the latching arm.

Abstract: A locking security arrangement is provided for both mounting an electronic component on and locking the component to a bracket assembly. A threaded shaft removably mounted on a tumbler of a lock assesmbly by threaded engagement in an aperture is inserted through a non-circular aperture in the bracket assembly. The shaft is advanced into a threaded aperture in a housing of the electronic component until a non-circular portion of a housing of the lock assembly approaches and then enters the non-circular aperture. A key inserted in the tumbler permits continued rotation of the threaded shaft through rotation of the tumbler relative to the lock assembly housing in response to turning movement of key, to continue advancing the threaded shaft into the threaded aperture in the housing of the electronic component until the non-circular portion of the housing of the lock assembly is completely seated within the non-circular aperture.

Abstract: Locking means for preventing or checking use of or access to objects such as, for example, mopeds, bicycles, cars etc. by unauthorized people, said device comprising a bar-type element, comprising a cylinder lock provided with a catch which can be moved at right angles to the axial direction of the cylinder lock by means of, for example, a key, which bar-type element can mate with and is to be placed in two or more holes which are or can be placed in line with each other, the first hole being provided with a groove or keyway which is directed from the inner surface of the hole to the outside, is circular, and the center point of which lines approximately axis of the hole, the latter hole being provided with a bottom, and the internal diameter of each hole corresponding to the external diameter of that part of the bar-type element which is placed in the hole when the bar-type element is in the closed position, and the holes with which the locking means must mate can be provided in one or more objects.

Abstract: A sliding shackle padlock for securing an outwardly opening door or closure provides a tapered shackle for cooperatively engaging the staple of a hasp or another fastening member on the door or closure, which may be removably secured to a door jamb. A protective cover is provided to conceal the locking arrangement between the tapered shackle and the staple or other fastening member. A ratchet arrangement or a spring clip arrangement is utilized to maintain the shackle in the shackled position within the staple or other fastening member.

Abstract: An improved trailer hitch is disclosed for coupling a towing vehicle and a trailer. The invention is suitable for accommodating both ball and socket-type couplings and ring and pintle-type couplings. The integral body of the trailer hitch has the known elements of a rear mount for attaching the body to a towing vehicle, a ball housing with a bore for mounting a removable ball stud, a plate for mating with a towed vehicle, and a passge for connecting a latching arm. The improvement comprises four elements. First, the latching arm has a head, having a front face and a rear face, and a pair of substantially parallel legs integrally attached to opposite sides of the head and extending beyond the faces of the head. Each leg has an aperture for mating with the passage of the integral body and engaging a pin. Second, to prevent rotation of the latching arm, a notch on the integral body seats the rear face of the latching arm.

Abstract: A plunger type lock has an elongate shank or housing with an enlarged head at one end and at least one lock element movable to project from the housing to engage a grooved or recessed member and lock the same to the housing and to retract into the housing to release the grooved or recessed member, a plunger movable in the housing by a special key to control the position of the lock element and an immovable security rod extending through the plunger and axially substantially to the end of the housing through which the key enters. Due to the presence of the security rod, a special key is required to operate the lock.

Abstract: Locking apparatus for bottom connected electrical meters which, in one embodiment, includes a secondary cover over the meter terminal block and intermediate the primary cover and the meter base, the secondary cover being secured to the base by screws which are covered by the primary cover. The secondary cover has an apertured stud thereon which extends through the primary cover and receives a lock to prevent removal of the primary cover. The protruding end of the stud may be covered by an apertured block secured to the primary cover. In a second embodiment, the stud is omitted, and the lock extends through the primary cover and into an opening in the meter base, the lock having a portion which engages the primary cover and prevents removal thereof. In the second embodiment, a detector, such as a switch, within the base and operable by the lock indicates the presence or absence of the lock.

Abstract: A magnetic lock which may serve, itself, as a locking device, or may form part of an otherwise conventional locking device, is provided with a body member, detent balls, and a detent locking plunger that is disposed in an axially extending interior space of the body member in a manner enabling the locking plunger to be displaced within the body member between a first location, at which the locking plunger causes the detent balls to be locked in a position protruding from the body member, and a second location at which the locking plunger enables the detent balls to retract into the body member. The body member is provided with a sealed end having a key seat upon which a key may be seated for shifting the locking plunger between its first and second locations.

Abstract: A locking assembly for utility meter boxes is disclosed, the assembly designed for connection to the meter box at the latch portion or the point of access to the box. The assembly has a bracket member for connection to the meter box and a cover member for engaging the bracket member and forming an enclosure around the point of access. A lock retaining member is disposed within this enclosure for engaging and retaining a lock therein, thereby preventing unauthorized removal of the cover member.

Abstract: A cable-lock device for securing an outboard motor vehicle to a marine vessel, wherein a cable with a phallic head inserted into a lock member, which comprising a sliding latch plate with a semi-circular opening which aligns with a groove in the phallic head to form a lock.

Abstract: A lock assembly for a meter housing asembly having a first housing panel fixedly mounted on a support member and a second housing panel mountable on the first housing panel and removable relative thereto along at least one predetermined line of travel, generally consisting of a retainer bracket having a first section detachably mounted on one of the housing panels and a second section engageable with the other of the housing panels when the first retainer bracket section is mounted on the one housing panel for restricting displacement of the second housing panel relative to the first housing panel along the predetermined line of travel in a direction tending to remove the second housing panel from the first housing panel, and means for locking the first retainer bracket section to the one housing panel when the first retainer bracket section is mounted on the one housing panel.

Abstract: A vehicle shift lever locking mechanism for retrofitting to motor vehicles includes in one form a universal adapter to enable the locking mechanism to be fitted to shift levers of a wide variety of motor vehicles. The universal adapter is received at least in part within a handle and a locking assembly is also received in part within the universal adapter and the handle so as to mechanically interlock the components in assembled relationship. The handle is designed to overlie the fastening arrangement which secures the universal adapter to the shift lever and thus prevents unauthorized removal of the locking mechanism. Embodiments of the locking mechanism are suited for either cable or rod actuated shift mechanisms. In another form the locking mechanism is formed for attachment to a steering column shift mechanism and includes a lock assembly movable within a housing mounted on the steering column to a position in which the lock assembly prevents pivotal releasing movement of the shift lever.

Abstract: An anti-theft device for semi-truck trailer landing gear of the type of telescoping concentric inner and outer cylinders which inhibits the landing gear from being raised by preventing the retraction of the inner cylinder into the outer cylinder, the anti-theft device defining an elongated pin adapted to reside in an opening situated transversely through the inner cylinder and located proximate the outer cylinder, the elongated pin having a head at one end, an extending and retractable cog emerging from the shank of the elongated pin proximate the head, and a locking means interiorly to the hollow bore of the elongated pin with the lock located at the end of the elongated pin opposite the head and connected with the cog in order to extend and retract it.

Abstract: A barrel lock and a key for locking and unlocking the barrel lock. The lock has a hollow barrel with a plunger that reciprocates within the bore of the barrel. The plunger is urged forwardly by a bottom spring, and a deterrent ring is urged forwardly against the plunger by a top spring. The plunger has a shallow axial blind bore at its rear end and the deterrent ring has a central aperture, the diameter of the plunger bore being larger than the diameter of the ring aperture.The key has four elongated outer expanding fingers and an inner expander rod. The expanding fingers are sized and shaped so that they can pass entirely through the central aperture of the deterrent ring. When the the key is inserted into the barrel lock and the key handle is operated, the fingers radially expand and grip the inner surface of the lock plunger blind bore. As the handle is operated further, the expanding fingers longitudinally retract and draw the plunger rearwardly permitting the lock to unlock.

Abstract: A locking device which may be used in locking two objects together, includes a stud having a threaded axial hole extending rearwardly from the forward end thereof and a keyed portion having at least one key, and a knob which locks over a forward portion of the stud and includes a casing with an inner surface including at least one keyway each of which receives the corresponding key on the stud to prevent rotation of the casing with respect to the stud. The knob also includes a tumbler housing which is mounted in an axially fixed position within the casing to rotate freely when a key is inserted into the tumbler housing, and to remain locked in a fixed position when the key is withdrawn. Connected to a rear end of the tumbler housing is a threaded stud which engages the threaded axial hole of the stud when the tumbler housing is turned by a key to thereby pull a forward portion of the stud into the casing hole.

Abstract: A barrel lock assembly for use in securing a lock housing over the latch or access point of a securable enclosure, such as a utility meter box, is disclosed, having a bar member with a stop on the distal end for engaging a surface on the lock housing or on the enclosure to be secured. A second bar member is disposed parallel to the first and has a head portion which receives the proximal end of the first bar member. The head and the first bar member have axially aligned apertures for receiving a suitable padlock and holding the assembly together.

Abstract: A key for a lock of the plunger operated type in which an elongated housing has an internal axially movable plunger which releases locking elements when moved toward the open end of the housing, said key having a body with elongated fingers extending forwardly from the housing and an elongated mandrel disposed between the fingers. A finger depth limiter or spacer is disposed at the rear end of the fingers and protrudes forwardly from the foremost face of the key housing for abutting a portion of the lock to limit the distance the fingers can extend into the lock. In one embodiment of the invention an axially adjustable cap is mounted on the forward end of the housing to allow adjustment of the amount the spacer projects from the housing.In one embodiment of the invention internal structure is provided that allows the fingers to shift forwardly a predetermined distance if the forward end of the housing is removed by grinding in an effort to modify the key for use in locks with which it is not intended for use.

Abstract: A concealed post lock includes an elongated cylindrical post having an enlarged head member secured at one end thereof and at least one locking member movably mounted at the other end thereof. The post contains a lock cylinder which is normally restrained from rotation within said post by locking pins but which are released by insertion of the proper key in the cylinder so that the cylinder may be rotated by the key. The cylinder is operatively coupled to the locking member for moving the locking member between a locked position and an unlocked position when the cylinder is turned within the post. In the unlocked position of the locking member, the locking member is located within the confines of the periphery of the post. In the locked position, the locking member projects outwardly from the periphery of the post.

Abstract: A cartridge lock having an elongated body and a rotary disc assembly, locking shaft, and at least one bolting element disposed therein. The rotary disc assembly comprises a plurality of discs aligned concentrically within a cylinder, which cylinder is interconnected to one end of the locking shaft by means transmitting turning force thereto. The bolting element is disposed within an aperture within the body and is moved to a position partially protruding therefrom when a bearing surface of the locking shaft is rotated and presented to the bolting element. The rotation of the locking shaft is determined by key action turning the rotary disc assembly from a locked to an unlocked position and the reverse.

Abstract: A double-acting barrel lock and key in which the lock has a hollow plunger which reciprocates between a security forward locking position and a normal rearward unlocking position. The lock also has a lock pin coaxially mounted within the hollow plunger for reciprocating between a forward unlocking position and a normal rearward locking position. When a nail-type pick is inserted into the rear of the lock and drives the lock pin forwardly to its unlocking position, a spring urges the hollow plunger forwardly to its security locking position in which the locking balls are maintained in their outward locking position.A key has double-acting means for simultaneously maintaining the hollow lock plunger in its normal rearward unlocking position while moving the lock pin to its forward unlocking position, thereby permitting the locking balls to move inwardly to their unlocking position.

Abstract: A two-part threaded locking mechanism is provided with complementary stop elements in the form of a pin and a recess that interengage when the two lock elements are threaded together. When used as a padlock, the locking mechanism may be encased in a tapered, spinnable, protective shroud. To facilitate assembly, the recess may be made larger than the pin and the surface adjacent the recess facing the pin may be spirally ramped.

Abstract: A plunger type lock comprising a barrel with an axial bore, locking members in the form of balls housed in the barrel wall and extensible outwardly from the barrel by a plunger axially slidable within the barrel bore, at least one further ball housed in an opening in the wall of the plunger and extensible outwardly therefrom and a peripheral groove on the inner wall surface of the barrel for receiving the further ball, the further ball being forceably moved and held in the barrel's groove by an incorrect key, instrument or an implement to prevent and resist movement of the plunger whenever an unauthorized attempt to operate and open the lock is made.

Abstract: A lock including an elongate member which is inserted into a lock housing, useful in locking structural frame members together, among other things.

Abstract: Methods and apparatus for releasably locking or blocking a door combine a first element with that door for blocking the door in an extended position of that first element and for alternatively releasing the door upon movement of the first element from such extended position. The first element is releasably blocked in its extended position by removably locating a second element in a path of movement of the first element. The door may be locked by locking the first element in its extended position and blocking such locked first element with the second element. The locked first element is released by selectively removing the second element from the path of movement of the first element, and the door is released by moving the released locked first element in its path of movement while the second element is removed from such path of movement. The first element may selectively be unlocked while it is blocked by the second element, and such blocked unlocked first element may be removed for a release of the door.

Abstract: A plunger operated lock in which the lock operating plunger is mounted in a plunger housing inside the lock housing and is axially movable therein. The plunger housing is spring biased to the locking position, and the plunger is spring biased to a medial position in relation to the plunger housing. To allow the plunger to move to the un-locking position, the plunger housing must be moved toward the unlocking position far enough to substantially fully compress its biasing spring, and the plunger must be moved axially in the plunger housing toward the unlocking position.

Abstract: A high security barrel lock and a high security key with a movable external sleeve for maintaining the lock in an unlocked position. The lock has a cylindrical barrel with an axial bore. A hollow plunger and a center pin with an enlarged head are axially mounted in the bore. A pair of locking balls are constrained for limited movement between locked and unlocked positions in radial passageways formed in the barrel. The sleeve is fitted over the barrel and is constrained for movement between a locking ball holding position and a locking ball releasing position. In the holding position, the sleeve holds the locking balls in their unlocked position and, in the releasing position, the locking balls are released by the sleeve and free to move radially outward in the barrel passageways into their locked position. Thus, the installer does not require a key in order to install the lock.

Abstract: A barrel lock has a cylindrical barrel with an axial bore. A compression spring and a center pin are coaxially mounted in the bore. A pair of locking balls mounted for limited movement in radially extending passageways are held radially outward in a locking position by the compression spring. When a key for locking and unlocking the lock is fully inserted into the lock and the key handle is operated, the compression spring is drawn rearwardly and the locking balls are permitted to move radially inward to an unlocking position.

Abstract: A high security spring lock and an associated key for locking and unlocking the lock. The lock has a cylindrical barrel with an axial bore. A main compression spring and a secondary compression spring are coaxially mounted in the bore and bear against each other and against opposite ends of the bore. A pair of locking balls constrained for limited movement in radially extending passageways are held radially outward in a locking position by the main compression spring.The key has elongated outer expanding fingers and an inner coaxially arranged center pin. When the key is fully inserted into the lock and the key handle is operated, the expanding fingers are initially radially expanded to grip the inner surface of the main compression spring and are then longitudinally retracted to draw the main compression spring rearwardly.

Abstract: A key for a lock of the plunger operated type in which an elongated housing has an internal axially movable plunger which releases locking elements when moved toward the open end of the housing, said key having a body with elongated fingers forwardly from the housing and an elongated mandrel disposed between the fingers. A spacer is disposed at the rear end of the fingers and protrudes forwardly from the foremost face of the key housing for abutting a portion of the lock to limit the distance the fingers can extend into the lock. The housing has a head portion which is axially adjustable in relation to the spacer to vary the amount the spacer projects forwardly from the housing.In one embodiment of the invention internal structure is provided that allows the fingers to shift forwardly a predetermined distance if the forward end of the housing is removed by grinding in an effort to modify the key for use in locks with which it is not intended for use.

Abstract: A locking device intended to be mounted on a fuel pipe nipple (15), which is provided with bayonet locking pins, so as to make it impossible to connect a fuel hose coupling to an outboard motor on a boat. The locking device comprises an elongated external sleeve (1), which at one end is provided with an internally situated lock (6) and at the other end with bayonet locking grooves (20,21,22,23) corresponding to the bayonet locking pins (16). The lock (6) has an axially movable locking piston (9) cooperating with an internal sleeve (14) which is axially displaceable inside the external sleeve (1) between a retracted first position, which permits relative interconnection and release, respectively, of the pipe nipple (15) and the locking device, and an advanced, second position in which the bayonet locking pins (16) are kept securely fixed in the bayonet locking grooves (22,23).

Abstract: A lock housing and lock assembly unit for use with electric and gas fuel meter enclosures and the like is disclosed, including a lock plunger for mating with a locking stud and biasing means for urging the plunger into the lock position. The plunger and biasing means are captured within the lock housing by a cap which is press fit or otherwise permanently installed in the housing or made of part thereof. Temporary detent means may be provided to position the plunger in the open position prior to installation. A key is inserted through a key hole in the cap and in a socket in the plunger to withdraw the plunger to the open position within the housing. The invention lends itself to various plunger-stud mating designs and is adaptable to lock-key surface mating for selective key operation.

Abstract: A pivotally mounted coupling guard, extending over a ball engaging socket of a trailer hitch to preclude disengagement of the socket from the ball, is locked in place to deter unauthorized disengagement of the socket from the ball and theft of the attached trailer. A lock module penetrably receives and locks therein essentially all of the extending ends of both the pivot pin and the retaining pin of the coupling guard to preclude unauthorized pivotal movement of the coupling guard.

Abstract: A high security lock and a high security key for locking and unlocking said lock. The lock has a resilient O-ring seated in the bore of a hollow plunger and a retainer sleeve fixed in the bore of the hollow plunger and bearing against the rear surface of the O-ring. A center pin with an enlarged forward head extends rearwardly through the bore of the plunger, the O-ring gripping the periphery of the center pin and yieldably resisting center pin reciprocal movement within the plunger bore.The key has elongated outer expanding fingers and an inner coaxially arranged center pin. When the key is fully inserted into the lock and the key handle is operated, the expanding fingers are initially radially expanded to grip the inner surface of the lock plunger bore, and are then longitudinally retracted to draw the plunger rearwardly. Simultaneously, the key center pin is prevented from retracting and holds the lock center pin stationary permitting the lock to unlock.

Abstract: Two generally flat, circular plates, one having an attached threaded male cylindrical shaped extension and the other an attached mating threaded female cylindrical shaped extension are threaded together through the ring of a trailer hitch tongue until the plates are in contact with the ring and held locked in threaded engagement by a latch to prevent the unauthorized use of the trailer. The latch is spring loaded and is extended through an opening in the side of the male cylinder to engage any one of a number of internal grooves coaxial with the cylinder, cut in the female cylinder, to provide the locking function. A single lobe cam contained within the male cylinder is mounted on the end of a conventional lock cylinder which, in turn, is rotated by a matching key.

Abstract: A shielded lock assembly suitable for joining first and second members together comprises in combination a shackle-bearing element having a body portion and a shackle carried thereby, and a lock body having a keyhole and having a shackle-receiving aperture opening in a given direction and adapted to receive and releasably retain the shackle therein. A housing is adapted to be secured to the first member, said housing defining an enclosure adapted to receive the lock body and having access openings communicating with the aperture and the keyhole, respectively. Means are operatively connected to the housing and engageable with the lock body for retaining the lock body in the enclosure.

Abstract: A locking device of the type having a lock cylinder containing a lock plug with a threaded rod connected thereto in a manner causing rotation of the rod with rotation of the lock plug by a key operating the tumbler includes a relatively massive cylindrical lock housing having a bore extending axially therethrough, the lock cylinder being fastened against rotational and axial movements relative to the lock housing, and a relatively massive cylindrical sleeve member with a blind bore therein and a screw threaded surface arrangement in a portion of the blind bore for threadingly engaging the threaded rod. In accordance with a first embodiment, relative rotation between the lock housing and the sleeve member is prevented by a counterbore in an open end of the blind bore of the sleeve member of non-circular transverse cross section and a portion of the exterior of the lock housing of reduced circumference, non-circular transverse cross section that is at least partially receivable in the counterbore.