Abstract: A lock includes a cylinder, a cylinder plug and a locking pin assembly. The cylinder plug is rotatably mounted in the cylinder and has a dummy keyhole and a cylinder plug keyhole defined completely through the cylinder plug. The locking pin assembly has multiple locking pins that are slidably partially held in the cylinder plug keyhole. A two step method to open the lock with a key with serrations initially inserts the key serrations into and presses the key serrations completely through the dummy keyhole. Then the serrations are rotated, aligned with and pulled back into the cylinder plug keyhole. Conventional displacement of the locking pins allows the cylinder plug to be rotated, which opens the lock. Pressing the key completely through the lock removes any foreign objects such as toothpicks, chewing gun or pieces of paper and allows the lock to be opened.

Abstract: A lock plug comprising a top end having a key way etched out of a solid wall, the key way leading to an interior of the lock plug housing a locking mechanism; and, a break away wall bordering a cavity carved out from the solid wall on a side of the key way, the break away wall forming a side of the key way. The locking mechanism in a lock plug usually employs the wafer technology and in this case, the interior of the lock plug includes a wafer cavity having wafers designed according to a particular key code.

Abstract: A lock includes a body defining a first bore having a lock core mounted therein, and a second bore having an engaging element inserted thereinto; and a front barrier shield fixedly mounted in the body in front of the lock core. A communicating hole is formed in the body behind the lock core to communicate the two bores. A locking pin is disposed in the communicating hole to move into or out of a locking hole formed on the engaging element under control of the lock core, so as to lock or release the engaging element to or from the body, respectively. The front barrier shield includes a plurality of axially spaced and staggered barrier sheets to define a zigzag keyway, preventing a thief from peeping through the first bore and destructing the lock core.

Abstract: The key with a lock-unlock indicator is operable with a complementary lock set. The key has a body and an elongated key stem extending therefrom. A toggle bar is pivotally mounted or disposed on the key stem. The toggle bar operates in conjunction with a lock cam and an unlock cam mounted on the face of the complementary lock set. When the operator turns the key in one direction, the lock cam motivates the toggle bar thereby shifting its position. An indicator disposed in the key body displaying a lock condition and an unlock condition.

Abstract: A security system for a storage container including a latch assembly disposed on an interior side of a door for latching the door in a closed position with the storage container. A plurality of reciprocating latch elements are included in the latch assembly for latching the door in a closed position with the storage container. A latch actuator included in the latch assembly moves the latch elements to latch the door. A master lock assembly controls operation of the latch actuator by having a first locking part of the master lock assembly interlocking with a second locking part carried by an elongated shaft connected to an operator on the container exterior. A tamper-resistant control blocks access to the master lock assembly from outside the storage container whereby access to the container interior is prevented when the latch assembly is closed and the master lock assembly is in an engaged position.

Abstract: A protective device for a padlock. The device includes a casing having a connecting member at either top or bottom, a cover formed at the top of the casing and a base formed at the bottom of the casing being connected to the top and bottom of the connecting member by soldering respectively, so that the casing, the cover and the base are adapted to enclose a body of the padlock. The base includes an opening having an annular downwardly extended flange for receiving a keyhole of the padlock, and an extension member having a recessed enlargement at one open end for being hingedly coupled to one side of the base, so that a pivotal movement of the extension member toward the base will snap the enlargement into and seal the opening.

Abstract: A lock assembly includes a lock cylinder, for actuating a latch assembly, including a lock sleeve, first and second lock rotors, having first and second keyways respectively, rototably fitted in the lock sleeve, and a plurality of tumblers for locking up the first and second lock rotors. A key includes a key head having predetermined locking serrations arranged in such a manner that when the key head is inserted into the first keyway, the locking serrations are adapted to unlock the first lock rotor and enable the first lock rotor freely rotating until the first keyway is aligned with the second keyway, simultaneously, the key head being adapted to insert into the second keyway such that the locking serrations are adapted to unlock the second lock rotor to enable the second lock rotor to freely rotate to control the locking and unlocking of the latch assembly.

Abstract: A tamper-evident seal is provided in combination with a keyed lock so that the seal prevents full accessability to the keyhole. The combination is especially suitable for security bags, and is applicable to any keyed lock.

Abstract: An internal locking device adapted for use with the magazine doors of a weapons storage facility to lock the magazine doors and secure the facility. The internal locking device use a dual key and key guides for key insertion and for reduction of key breakage. The internal locking device includes a pair of locking bolts which when dis-engaged from the output shaft by an operator rotating the keys allows the operator turn handle which turns the output shaft for the device unlocking the magazine doors.

Abstract: An internal locking device adapted for use with the magazine doors of a weapons storage facility to lock the magazine doors and secure the facility. The internal locking device use a single key and key guide for key insertion and for reduction of key breakage. The internal locking device includes a locking bolt which when dis-engaged from the output shaft by an operator rotating the key allows the operator turn handle which turns the output shaft for the device unlocking the magazine doors.

Abstract: An improved internal component lock for storage containers is disclosed which comprises a body having a hasp space, a keyway and a retaining space. The hasp space, the keyway and a retaining space are joined within said body. The keyway has a locking mechanism contained therein. The locking mechanism actuates a shackle which is adapted to slidably extend from the locking mechanism across the hasp space to the retaining space when the locking mechanism is in the locked position. The shackle engages a hasp extending into the hasp space in the locked position while being retained within locking mechanism in the unlocked position. At least two retaining pins have a shaped upper edge adapted to deter drilling and are vertically mounted on either side of the retaining space to retain the shackle therewithin when in the locked position.

Abstract: A lock-and-alarm assembly includes an escutcheon formed with a through-hole. A lock core is formed with a keyway that can be accessed through the through-hole. A blind is detachably mounted in the through-hole for blocking access to the keyway through the through-hole. A switch is connected to the blind and is actuated upon removal of the blind, which, in turn, results in actuation of an alarm.

Abstract: A lock has a first steel plate having a first through hole defined to correspond to the core of the body, a circular cap movably received in the first through hole and having a slit defined to correspond to the keyhole of the core. A second steel plate is securely attached to the first steel plate and has a second through hole corresponding to the first through hole and bores corresponding to the holes of the first steel plate. A protection cap is securely attached to a bottom of the second steel plate and a distal edge of the protection cap is securely connected to an outer face of the body. The protection cap has an opening defined to correspond to the second through hole.

Abstract: The inventive device comprises a seat which is situated in the device housing and which is provided for the insertion of an identification provider. A holding element located inside the seat engages with a lateral indentation of the identification provider. The opening of the seat is normally closed by a spring-loaded cover element. In order to create a functionally reliable and economic design, the invention provides that the cover element is configured as a pivotal flap which can pivot from the identification provider out of an outwardly pivoted position covering the opening of the seat and into an inwardly pivoted position inside the seat. A projection is provided on the outer side of the flap and functions as a holding element for the identification provider. A recess is arranged next to the seat for the inward pivotal movement of the flap.

Abstract: A device for locking a piston rod of a hydraulic piston and cylinder assembly in an extended condition. The locking device is placed in interposed relation to a hydraulic cylinder and an opposing bearing point to prevent retraction of the piston rod. The device has a split sleeve configuration to facilitate mounting the locking device in encircling relating to the piston rod including opposed longitudinally extending edges that are locked to one another via a locking means. The locking means of the device is partially enclosed by a lock protecting housing to protect the locking device from being removed by unauthorized persons. The device is durable, easy to install and remove, and adaptable to a variety of hydraulic piston and cylinder assemblies.

Abstract: A lockable cap is disclosed which includes a base having an opening penetrating through the base plate, an openable cover pivotably mounted on the base for releasably covering the opening, an elastic member for elastically thrusting the cover in an opening direction for exposing the opening, a latch member for retaining the cover in a closed position with respect to the base against elastic thrust applied by the elastic member, a key-operated lock disposed in the base, a key-for setting and opening the key-operated lock, and a latch releasing member attached to the key-operated lock for releasing the latch member to open the cover when the key is inserted into the lock to open.

Abstract: A keylock cover for an electronic system housing such as a computer system housing. The keylock cover is movably coupled to the housing to move between an open position where the keylock is exposed, to a closed position where the keylock is hidden from view. The keylock cover may be secured in a closed position with a push-push latch mounted in the housing. The keylock cover may include a key retainer that retains a key that is compatible with the keylock to the keylock cover. Computer system identification information such as vender names or product names can be located on the outer side of the keylock cover. In one example, the keylock cover is movably coupled to a bezel of the electronic system housing.

Abstract: A protective sleeve for a padlock includes a sleeve body having an open inserting end adapted for insertion of a lock body of the padlock into the sleeve body, a restricting end opposite to the inserting end and adapted for abutting against the lock body, and a surrounding wall extending between the inserting end and the restricting end and adapted to wrap fittingly around the lock body. The sleeve body is formed with a key opening adapted to be aligned with a keyhole of the lock body. A cover flap is hinged to the sleeve body at the key opening, and is movable pivotally between an open position adapted for permitting access to the keyhole, and a closed position adapted for closing the keyhole. The cover flap is formed with a plug adapted to be inserted into the keyhole when the cover flap is moved to the closed position.

Abstract: A padlock assembly includes a first lock casing part having a lock core mounting portion formed with a core receiving space in a longitudinal direction, and a first shackle mounting portion that extends in a first transverse direction from one side of the lock core mounting portion. A lock mechanism includes a key operated lock core disposed rotatably in the core receiving space, and a latch member connected to one end of the lock core in such a manner that the latch member is disposed outwardly of the core receiving space. A second lock casing part has a latch engaging portion formed with a latch recess and a latch retainer disposed therein to partition the latch recess into a latch retention portion and a latch entrance portion via which the latch member is extendible into the latch retention portion and so as to be rotatable therein between locking and unlocking positions.

Abstract: A protective cover for a keyhole of a lock includes a cap and a pair of shutters. The cap has a crown and a skirt. The crown defines a central through-hole and a pair of radial slots at opposite sides of the central through-hole. The skirt is intended to be connected to the lock rotatably around the keyhole. The shutters each have a first end and a second end, with the first ends pivoted on the lock diametrically about the keyhole, and the second ends formed with respective stubs movable in the slots of the cap. Additionally, the shutters are configured to close the central through-hole of the crown when the cap is turned in a direction relative to the lock and to open the central through-hole of the crown when the cap is turned in an opposite direction relative to the lock.

Abstract: A keyway protector having housing and the slider. The housing hugs the crossbar of a U-lock and secured by screws. The slider fits into a shallow depression in the inner surface of the housing and moves between open and closed positions. In the open position, an aperture in the housing, a hole in the slider, and the keyway are aligned to allow access to the keyway. In the closed position, the slider hole is not aligned, denying access to the keyway. A knob outside the housing is used to move the slider. Protrusions in opposed pivoting arms on the slider snap into opposed notches in the depression walls to hold the slider in the open or closed position.

Abstract: An apparatus for insertion of a key therein substantially prevents foreign matter from entering into a key insertion hole, and even if foreign matter does enter into the key insertion hole, discharges the foreign matter therefrom. A shutter is provided within the key insertion hole so as to be movable along a direction of insertion of a key. The shutter is always urged by a compression coil spring toward an opening of the insertion hole. In a state in which no key is inserted in the insertion hole, the shutter is urged by the compression coil spring and closes the insertion hole. As a result, foreign matter such as dust or the like can be prevented from entering into the insertion hole. Further, the shutter is provided with a reflecting surface, and when no key is inserted in the insertion hole, the reflecting surface reflects light from a light source so as to illuminate the opening of the insertion hole.

Abstract: The invention relates to a locking device having a barrel housing (2) which consists of a lower part (3) and a metallic upper part (4) and which surrounds a cylinder housing (5) which consists of metal and in which there is rotatably mounted a cylinder core (6) which can be locked to the cylinder housing (5) via tumblers (7).

Abstract: A motorcycle having a fork lock includes a cover which is adapted to be manually moved between a cover position where the cover overlies the fork lock and an uncovered position where the fork lock is exposed to allow a key to be inserted into the fork lock. The fork lock is attached to a mounting member carried between a pair of handle bars for the motorcycle. This mounting member includes a raised platform of a predetermined configuration in which the fork lock is seated. The cover includes a cover plate and a base plate, and the base plate has an underside to which is secured a double sided adhesive member. A first side of the adhesive member is bonded to the underside of the base plate and the second side of the adhesive member having an adhesive surface.

Abstract: The invention proposes a handle for the door of an automobile vehicle, of the type in which the handle comprises an external gripping lever that is designed to be moved by a user from a rest position to an open position to control a lock that is associated with a lock cylinder of the type comprising a stator, one end of which is accessible from the outside so that a key can be inserted in the lock cylinder through a slit that opens out into the end of the cylinder, wherein the gripping lever comprises a protective cap and/or trim covering the lock cylinder that is assembled so that it is free to slide with respect to the gripping lever between a normal assembly position in which the cap conceals at least the slit in the lock cylinder when the gripping lever is in its rest position, and a displaced position enabling access to the key insertion slit.

Abstract: Disclosed is an improved cylinder construction for use with a lock system. The cylinder services to frustrate the use of lock picking tools, such as a tensioning device. Specifically, a pair of opposing flat regions are formed at the lower end of the cylinder. Furthermore, the key way formed within the cylinder has an opened lower end. These features make a system which is completely resistant to picking by way of traditional pick tools. Furthermore, the cylinder cannot be broken by way of a screwdriver or drill.

Abstract: An electronic lock housing assembly provides a lock retrofit for a transportation industry-standard cargo door lock assembly. The electronic lock assembly is configured to protect the electronic components of the lock from impact, moisture and foreign matter. The exterior housing retains an electronic lock cylinder and its cam assembly at the exterior of truck door, so as to engage the rotatable lever of a standard mechanical door latch assembly. The interior housing retains the lock's electronic circuitry directly behind the exterior housing on the opposite, interior side of the door, so as to facilitate electrical interconnection through a mechanically shielded channel in the door.

Abstract: A removable core cylinder assembly which utilizes a plurality of modular parts to create a key-removable interchangeable core which will fit all existing interchangeable core locks of this kind.

Abstract: A pick-resistant lock system including an essentially cylindrical housing with an axial cylindrical bore and a plurality of radial bores spaced along the cylindrical bore and constituting a pin chamber, the radial bores having open ends in communication with the axial bore; a rotatable main cylinder rotatably located within the axial bore, the man cylinder having radial bores alienable with the radial bores of the housing and a planar key way alienable with the radial bores when in the locked orientation; a plurality of pins formed of plural segments positionable within the radial bores of the housing and main cylinder and with springs urging the pins toward the key way, the segments of the pins having interfaces which are alienable with the interface between the bores of the main cylinder and housing; a generally cylindrical facing cylinder axially alienable with the main cylinder and freely rotatable with respect thereto, the facing cylinder having an enlargement matable with a complementary recess in the h

Abstract: A combination key lock for a vehicle lock cylinder having a keyhole including two flanges, each having a throughbore, integrally disposed on either side of the keyhole. The throughbores receive the shackle of a conventional padlock. The invention also provides for aftermarket reconfiguration of manufacturer-installed lock cylinders.

Abstract: A keyhole-shutter structure includes a cylindrical protector block. An upper portion of the protector block includes an approximately square housing portion. A shutter plate is fitted in the housing portion. A cap is placed on the protector block. The bottom of the housing portion has right and left receiving planes for receiving the shutter plate, and a recess formed between the right and left receiving planes in such a manner as to be curved downwardly. Since a recess is provided between right and left receiving planes for receiving a shutter plate, even if the shutter plate is somewhat deformed, the deformed portion interferes to a lesser extent with the recess. Accordingly, a key can be easily inserted into a keyhole even if the shutter plate is somewhat deformed.

Abstract: A pick-resistant lock system including an essentially cylindrical housing with an axial cylindrical bore and a plurality of radial bores spaced along the cylindrical bore and constituting a pin chamber, the radial bores having open ends in communication with the axial bore; a rotatable main cylinder rotatably located within the axial bore, the man cylinder having radial bores alignable with the radial bores of the housing and a planar key way alignable with the radial bores when in the locked orientations; a plurality of pins formed of plural segments positionable within the radial bores of the housing and main cylinder and with springs urging the pins toward the key way, the segments of the pins having interfaces which are alignable with the interface between the bores of the main cylinder and housing; a generally cylindrical facing cylinder axially alignable with the main cylinder and freely rotatable with respect thereto, the facing cylinder having an enlargement matable with a complementary recess in the

Abstract: The invention relates to a catch for a door, especially a switchboard door, with a lock plate which can be secured to the door and bears a door lock and a bolt cover guided adjustably on the lock plate which can be secured in a position covering the door lock by means of a cover lock. Complete sealing with substantially increased security against unauthorized access to the door lock is attained in that the door lock takes the form of a casement lock and the cover lock that of a cylinder lock, a partial cover is secured to the lock plate which overlaps with the bolt cover in the locked position at the contact point and forms a sealed lock cover, and a cover for the cylinder lock is rotatably fitted on the bolt cover.

Abstract: A protector block is movable in a direction in which a key K can be inserted, and first engaging portions which engage each other when the protector block is pushed in are formed between the protector block and an outer lock cylinder. A crankshaft is movable in the direction in which the key K can be inserted, and second engaging portions which engage each other when the crankshaft is pushed in are formed between the crankshaft and the outer lock cylinder. When an object in place of a key is inserted into a key insertion hole and attempts are made to forcibly turn the object while pushing the object, the first engaging portions between the protector block and the outer lock cylinder engage each other, preventing the crankshaft from being turned. When attempts are made to turn an inserted object while pulling the object, the second engaging portions between the crankshaft and the outer lock cylinder engage each other, preventing the crankshaft from being turned.

Abstract: A locking mechanism comprising a lock housing mounted in a hinged unit or the like and a bolt mounted to a fixture. The housing has a hole therein for receiving an end of the bolt. The bolt end includes a locking aperture for receiving a shackle of a padlock. The padlock locks around the locking aperture and is then positioned inside housing 20 to protect the padlock from being cut or broken. The novel design of the locking aperture allows the padlock to be selectively positioned in one of three positions, and thus fit within a narrow cavity not much large than the size of the padlock.

Abstract: A housing for externally mounting an electronic lock to a support structure has a conical sidewall joining front and rear faces of the housing. A cavity extending to the front and rear faces receives the electronic lock, such that a key access face of the lock coincides with the housing's front face. The rear face of the housing has an indented region to which a pivot bracket is mounted. The pivot bracket rotatably engages a pivot shaft coupled to a hinge plate of a pivotable front cover, which is spring biased against the front face of the housing. The housings's conical sidewall has a slot intersecting the indented region. The hinge plate is configured to conform with the slot and the housing sidewall, when the cover is closed against the front face of the housing. A rear end of the hinge plate is tapered so that as said hinge plate rotates about its pivot axis, it clears the structure to which the housing is mounted.

Abstract: A motorcycle having a fork lock includes a cover which is adapted to be manually moved between a cover position where the cover overlies the fork lock and an uncovered position where the fork lock is exposed to allow a key to be inserted into the fork lock. The cover has a pivot member pivotally connecting the cover to the motorcycle to enable the cover to be rotated with respect to the fork lock to expose the fork lock so that the key may be inserted into the fork lock. A detent member maintains the relative position of the cover to the motorcycle so that the cover overlies the fork lock to cover the fork lock until a turning force is applied to the cover to move the cover between the cover position and the uncovered position.

Abstract: An exterior door lock cover (22) comprising a flexible sleeve (24) which fits over an exterior exposed lock member (10) having a keyhole (12) on an exterior door (16). The flexible sleeve (24) will stop any contaminants (20) from entering the keyhole (12) in the lock member (10) which can accumulate and clog the lock member (10) and prevent the proper insertion of a key (26) into the keyhole (12) for operating the lock member (10).

Abstract: A lock housing with a key way blocking means for selectively blocking the key way includes a pair of meshing halve lock housings, and a circular ring turnably secured on one of the lock housing. The circular ring includes an aperture at one side which is sized and shaped in correspondance with the key way of the lock housing. When the circular ring is turned to a first direction, the key way of the lock housing is exposed outwardly for insertion of a legal key to unlock the lock. When the circular is turned to a second direction, the aperture of the ring departs away from and blocks the key way.

Abstract: An improved dust shutter assembly for locks includes a floating hinge point which decreases the amount of axial key force that is necessary to overcome the spring bias in the dust shutter mechanism. When engaged by a key, the spring retention pin (hinge point) of the dust shutter mechanism moves within the pin slots of the lock plug cavity until it bottoms out against the back of these slots. Pin translation is primarily axial, in the direction of key insertion, which partially unloads the spring and reduces the amount of key force that is required to open the shutter door. Since less key force is necessary, a narrower shutter door can be used. The chief advantage of a narrower shutter door includes a corresponding reduction in the size and length of the entire lock assembly.

Abstract: A lock system adapted to be used with both conventional mortise and cylinder locks includes an electronic socket to removably receive a button-like metal casing having an integrated circuit therein. The socket transmits code to a microprocessor based circuit which control a rotary two-directional motor. In one embodiment, the motor turns a cam which lifts, or lowers, a frame-like slide having a plunger which fits into a cavity of the cylinder to lock the cylinder.

Abstract: A cylindrical lock includes a casing having an annular front face with an inner circumferential portion surrounding a key insert member received by a key. A keyhole is defined between the inner circumferential portion and the key insert member, a lower portion of the key insert member is displaced from an axial center of a lock cylinder by a predetermined distance. The key includes a cylindrical end received by the key hole. A thickness of an upper side of the cylindrical end is different from a thickness of the lower end such that, when the key is rotated, the displaced lower side of the key insert member causes a width of portions of the keyhole to be varied. Thus picking of the cylindrical lock with a picking tool or the like is prevented.

Abstract: A protective guard is provided for a lock cylinder in a door, which consists of a generally rectangular metal plate assembly having a central passageway therethrough. Components are for attaching the plate assembly to the door with the central passageway generally aligned with the lock cylinder. The attaching components are concealed, removable and adjustably connected to an inner side of the plate assembly, thereby rendering the lock cylinder less susceptible to tampering.

Abstract: A lockable container is disclosed which has a base part and a cover which is pivotally attached to the base part. A lock has a lock catch which is adjustable between a locking position and a free position via key activation of the lock from the outside of the container. In its interior, the container is provided with a holder for a key belonging to the lock. The holder is arranged to form a storage place for the key and to securely hold the key when the lock is not being used. The holder is so located with respect to the lock that the lock catch, through mechanical contact with the key, is kept out of the locking position even when the cover is closed.

Abstract: A housing container includes a front door plate employing spring hinges is hingedly mounted relative to the housing container, wherein the door plate includes a latch plate having a plurality of lock levers to be operated simultaneously and each independently pivotally mounted relative to an interior surface of the door plate, with the lock levers accessed through individual openings directed through the door plate. Upon displacement of the lock levers relative to a sliding lock plate, the lock plate is displaced relative to a latch flange portion within the container by displacement of a lock plate lug slidably mounted through a slot directed through the door plate below the access openings.

Abstract: A gang mail box for an apartment building comprising an outer frame and an inner frame. The inner frame is pivotally connected to the outer frame which is secured to a wall of the building. A number of individual mail boxes corresponding to the number of apartments are mounted on and pivotal with the inner frame. These individual mail boxes are shaped so when the inner frame is pivoted, the tops of the individual mail boxes are exposed so the mail carrier can insert mail in them. Each mail box is provided with a hinged door having an individual mail box lock. A tempered steel security bar is provided to cover and conceal the tenants' locks on the individual mail boxes to prevent theft. This bar is hinged to the inner frame and is provided with a padlock for securing the bar in place.

Abstract: A flush mounted lock protector is provided that includes two cup portions joined by a hinge. Each cup portion has an interengaging lip for sealing engagement with the other cup portion. The lower cup portion includes an access port for placement about a flush mounted lock and adhesive means to secure the device about the lock. The upper cup includes a tab and a raised depressible dome portion which allows the upper cup to be enlarged therefore releasing the sealing engagement with the lower cup and breaking any ice that may form about the invention.

Abstract: An access cover plate is secured to a door by tamper-proof fasteners. A hole in the cover plate is concentric with a cylinder lock keyhole and provides access for the key and actuation of the primary lock. The cover plate access hole is closed off by a removable threaded plug which engages female threads in the hole of the cover plate. When secured in place, the plug is forcibly tightened against the face of the cylinder lock. The plug includes a recessed, tamper-proof wrenchable socket which permits removal of the plug only by a specially designed socket wrench. The tamper-proof socket has a polygonal wall and an axial guard pin.

Abstract: A mail box for an apartment building comprising a number of individual mail boxes corresponding to the number of tenants. Each mail box has an individual mail box lock. Releasable locking means are connected to the mail boxy for covering the individual mail box locks until mail is to be removed to prevent theft. Unlocking means are provided for unlocking the releasable locking means to expose the individual tenants lock so they can get their mail.

Abstract: A combined lock device comprised of a key lock linked up with at least one combination lock. The key lock can be unlocked by a key only when the combination lock is unlocked. A division plate is mounted on the lock device to alternatively conceal the key lock and the at least one combination lock, so as to prohibit the key lock and the at least one combination lock from being simultaneously exposed to thieves' eyes. The lock bolt which is driven by the key to fasten a door, strongbox, etc. has a notch on the slope of the front end thereof to protect against insertion of a pry.