63results about How to "Achieve the purpose of unlocking" patented technology

The invention discloses a building conversational system constructed by a public telephone network, which utilizes a public telephone access network as the physical connection of the network, uses an LAN-used program control switcher as a communication switch control device; the system of the invention comprises a doorway control terminal which is responsible for initiating calls and performing the action of opening door; a household telephone terminal, the LAN-used program control switcher responsible for changing information is connected with the doorway control terminal and household telephone terminal by a telephone line or a wireless access network base station, and sets the households managed by the same door as a group by utilizing the VPN telephone function of a virtual group, supplies each household in the group with a short number which is the same as the room number of the households and realizes a communication function; in the invention, the systerm also comprises a part of traditional entrance guard system and a public telephone access network. The system of the invention utilizes a fixed or mobile telephone network, adopts a room number as a communication number and realizes a function calling households by telephones; after a control signal of the telephone of the households is found, a driving circuit is unlocked; the system has low investment cost and high stability and reduces the cost and difficulty of maintenance.

The invention relates to the field of locks, in particular to a combination of an antitheft padlock and a key. The combination comprises the key and the padlock. The padlock comprises an unlocking device. The unlocking device comprises an unlocking column (24), the unlocking column (24) and a lock cylinder tail (11) are coaxial, and the unlocking column (24) is used for rotating to squeeze a compressed spring (8). A gap is formed between the end, away from the compressed spring (8), of the unlocking column (24) and the lock cylinder tail (11). The unlocking column (24) is further provided with a second key hole (25) allowing a key body (2) to be inserted into so that the unlocking column (24) can be driven to rotate. The combination of the antitheft padlock and the key has the better antitheft effect.

The invention discloses an electronic lock and an unlocking method thereof. The electronic lock comprises an electronic lock cylinder and an electronic key. The electronic lock cylinder comprises a lock cylinder body, a fixing piece, a drilling resistant cap and a stretchable connecting rod. The lock cylinder body is fixedly connected with the drilling resistant cap through the fixing piece. An electronic lock head is arranged at the end of the lock cylinder body. A controller module is arranged inside the lock cylinder body. The electronic key comprises a key body, a power source and a microprocessing unit. A recognition head matched with the electronic lock head is arranged at one end of the key body. The unlocking method comprises the steps that firstly, the electronic key is authenticated through computer management software; secondly, the electronic key makes contact with the electronic lock cylinder, the electronic lock cylinder is powered by the power source in the electronic key, the controller module in the electronic lock cylinder judges whether passwords on the electronic key are correct or nor, and unlocking or unlocking rejection is completed. According to the electronic lock, the electronic lock cylinder of one size can be universal to doors and locks of all sizes, the electronic lock cylinder and the electronic key are cooperated to work, no continuous power-on is needed, low power consumption of the electronic lock is achieved, the maintenance cost of the electronic lock is lowered, and unlocking is safe and convenient.

A lock head of an anti-theft lock comprises a lock cylinder sleeve, a lock cylinder and a return device. The lock cylinder is provided with a key slot, inner marble holes, left inner installation holes and right inner installation holes, the key slot comprises an upper slot body, an arc-shaped slant contract slot body and a lower slot body, and the arc-shaped slant contract slot body is located between the upper slot body and the lower slot body; the lock cylinder sleeve is provided with a lock cylinder hole, outer marble holes, left outer installation holes and right outer installation holes, and a bilateral gap s, a bilateral gap t and a bilateral gap u are unequal to one another; the lock cylinder is installed in the lock cylinder hole formed in the lock cylinder sleeve, upper springs, upper flat head marbles and upper half round head marbles are sequentially arranged in the outer marble holes and the inner marble holes, and the outer marble holes are closed through plugs; the return device comprises left springs, left flat head marbles and left half round head marbles which are sequentially installed in the left inner installation holes and the left outer installation holes and right springs, right flat head marbles and right half round head marbles which are symmetrically installed in the right inner installation holes and the right outer installation holes, and the left outer installation holes and the right outer installation holes are closed through plugs.

The invention relates to a dual-purpose padlock. A lock plunger matches with a ball and other internal components for actuating, an external part is protruded to form a gap, thereby achieving unlocking in a manner of inputting a password or using a key according to the requirement of a user, i.e., the key is used to directly rotate a lock core to enable the lock plunger to be automatically ejected, thereby achieving the purpose of unlocking. The user can only apply force to press the lock plunger into the housing so as to enable the ball to be fixedly embeded on the lock plunger and enable the lock plunger to lock up, thereby achieving locking. The padlock is direct, quick and more convenient to use.

A door lock (100) comprises a door lock box (101). The door lock box (101) comprises a locking device (230), a magnet (235) arranged on the locking device (230) and a release hole (265) formed in the door lock box (101). The locking device (230) has a locking position and a releasing position, the door lock (100) is closed when the locking device (230) is at the locking position, and the door lock (100) is released when the locking device (230) is at the releasing position. The release hole (265) is used for allowing an unlocking magnet (254) to be inserted, and when the unlocking magnet (254) is inserted into the release hole (265), the magnet (235) on the locking device (230) is pushed, and the locking device (230) is moved to the releasing position. The door lock can be opened when an electric appliance is powered off.

The invention relates to a metal door lock part, and discloses a door lock latch bolt drive mechanism. The door lock latch bolt drive mechanism is provided with a lock box assembly, a latch bolt assembly, a rotary damper, a shifting core, a latch bolt shifting plate and a shifting core torsion spring, wherein the rotary damper is screwed and fixed in the lock box assembly, the latch bolt assembly is placed in the lock box assembly, a rack arranged on the latch bolt assembly is meshed with a damping gear of the rotary damper, the shifting core is embedded and fixed in the lock box assembly, and the latch bolt shifting plate and the shifting core torsion spring are arranged on the latch bolt assembly in a penetrating manner. The shifting core is clockwise rotated to drive the latch bolt shifting plate to rotate, the latch bolt shifting plate drives the latch bolt assembly to retract, so that the purpose of opening a door is achieved; when no external force is applied to the shifting core, because of an elastic force action of the shifting core torsion spring, the shifting core and the latch bolt shifting plate return an initial position, a reset spring pushes the latch bolt assembly out, and thus the purpose of closing the door is achieved. In a movement process of opening the door and closing the door, due to the action of the rotary damper, the latch assembly moves slowly, and thus the collision noise among parts is reduced.

The invention discloses an oil tank anti-theft system, which includes a mechanical coded lock; the mechanical coded lock includes a key fixing seat, a connecting cover, a mechanical lock core and a chuck; a button is arranged at the top of the key fixing seat; the connecting cover, the mechanical lock core and the chuck are sequentially arranged in the key fixing seat and the mechanical lock coreis arranged on the chuck; the chuck extends into the oil filling port of the oil tank; the button includes a plurality of unlocking buttons, a plurality of code destroying buttons and a locking button; sequentially pressing the unlocking button according to the unlocking password sequence to drive the mechanical lock core to step out of the lock gradually; pressing any code destroying button and the locking button can drive the mechanical lock core to lock the oil filling port of the oil tank to limit the extraction of the key fixing seat. According to oil tank anti-theft system, the structureis ingenious. The mechanical lock is not easily damaged. The mechanical coded lock adopts mechanical transmission and the safety of the fuel in the oil tank is guaranteed. The design of the unlockingbutton and the destroying button avoids code being peeped. The password can be input in a false action and the password leakage is prevented.

The invention relates to an electronic cabinet lock capable of being unlocked in an electromagnetically driven mode, which is designed to solve the technical problems that locking limited design between electromagnets and buttons in existing similar products is not reasonable, and an unlocking mode is relatively single. A pedestal of the electronic cabinet lock and a bottom plate of the electronic cabinet lock are locked; one end of a handle is hinged to one end of a rotary shaft; the other end of the rotary shaft extends to the outside of the pedestal and the bottom plate; an electromagnet switch is connected with an electromagnet assembly through a circuit; and the electromagnet assembly is connected with a power supply circuit. The key point of the electronic cabinet lock is that an electromagnet latch of the electromagnet assembly extends into the other end of the handle, i.e., the handle at the end and one end of the pedestal are locked through the electromagnet latch of the electromagnet assembly; the buttons are arranged on the handle at the locked position; the buttons comprise a left button and a right button; latch hooks of the buttons are locked with an inside groove of the pedestal; and the electromagnet latch of the electromagnet assembly is also positioned on the latch hooks of the buttons. The other end of the pedestal is equipped with an electronic lock cylinder assembly; a charging hole is formed in the electronic lock cylinder assembly of the pedestal; and the electronic lock cylinder assembly and the charging hole are sealed in a dustproof cover.

A mechanical and fingerprinting dual-purpose handle lock comprises a front handle, wherein the front handle is provided with a sleeve A and a sleeve B which are mutually connected, and a fingerprint module is arranged on the sleeve A; the fingerprint module is connected with a lock body through a motor, and a lock cylinder is arranged in the sleeve B and connected with a clutch mechanism; the clutch mechanism comprises a rotating shaft, a clutch driving part B and magnetic elements arranged on the rotating shaft and the clutch driving part B; the rotating shaft can rotate forwards or reversely for 180 degrees; the clutch driving part B and the rotating shaft are attached or separated through magnetic field commutation. When a key is inserted into the lock cylinder and rotates for 180 degrees, a magnetic bead B on the rotating shaft and a magnetic bead A on a clutch driving part A can be separated or attached, when the magnetic bead A and the magnetic bead B are separated, the clutch driving part A can be downwards clamped with the clutch driving part B under the action of repellent acting force of the magnetic beads, and the unlocking purpose is achieved; when the magnetic bead A and the magnetic bead B are attached, the clutch driving part A and the clutch driving part B can be separated, and the locking state is realized at the moment.

The invention discloses a smart home security system. The smart home security system comprises a door lock mechanism, a video monitoring mechanism and a central controller; the door lock mechanism comprises a lock body, a lock cylinder is installed in the lock body, an electromagnet is installed in the lock body, the front end of the electromagnet is connected with a ferromagnetic safety pin through a spring, a square hole is formed in the bottom face of the ferromagnetic safety pin, a limiting pin is arranged on the lock cylinder, the square hole is matched with the limiting pin in an inserted mode when the electromagnet is not powered on, the ferromagnetic safety pin is attracted by the electromagnet to enable the square hole to be separated from the limiting pin when the electromagnet is powered on, and an electric control unit of the electromagnet is in communication connection with the central controller; and the door lock mechanism further comprises a plurality of keys matched with the lock cylinder, RFID cards are installed in the keys, the RFID cards of different keys are different, a card reader used for reading the RFID cards is installed in the lock body, and the card reader is in communication connection with the central controller. According to the smart home security system, the defects in the prior art can be overcome, and the security level of the smart home security system is improved.

The invention relates to an electromechanical transformation control device of an anti-theft lock. A lock core, a lock tongue and an unlocking component are installed on a shell of the anti-theft lock; the lock core is provided with a key hole; the electromechanical transformation control device is characterized in that: the lock core is also provided with a lock core pulling sleeve which is provided with an unlocking linkage; an electromechanical transformation switch is also arranged on the shell near the lock core pulling sleeve; a switch touch sheet of the electromechanical transformation switch is close to the lock core pulling sleeve; the shell is also equipped with an electromagnet and an electromechanical transformation control panel; one end of the electromechanical transformation control panel is connected with a lock tongue component and the electromagnet is electrically connected with the electromechanical transformation switch; and the middle axis on the electromagnet is close to the electromechanical transformation control panel. The electromechanical transformation control device has the advantages that: the structure is simple and rational, and the lock can be opened by a mechanical and electronic combined way so that the anti-theft performance of products is improved.

The invention relates to the field of safety antitheft, in particular to a combined anti-theft lock. The combined anti-theft lock comprises a lock body, a main lock body and an auxiliary lock body, wherein the main lock body and the auxiliary lock body are arranged on the lock body. The main lock body comprises a main lock cylinder plate and a lock column. The main lock cylinder plate is fixedly connected with the lock column through a main lock transmission device. When the main lock cylinder plate rotates, the main lock transmission device drives the lock column to stretch out of the lock body. The auxiliary lock body comprises an auxiliary lock cylinder, an auxiliary lock drive device and an auxiliary lock connecting device which are connected in sequence. When the auxiliary lock cylinder rotates, the auxiliary lock drive device drives the auxiliary lock connecting device to move, and when the auxiliary lock connecting device moves to the maximum displacement position, the auxiliary lock connecting device ejects the lock column. The combined anti-theft lock is simple in structure and high in safety, lock opening and closing functions are achieved through the main lock body, secondary locking is carried out after the main lock body is locked through the auxiliary lock body, and therefore the safety of the combined anti-theft lock is improved.

The invention discloses a dial lock with a key and the dial lock comprises a lock body and a shackle. Cooperating with each other, a plug and a lock head are arranged in the lock body. The plug is connected flexibly with the lower part of the lock body. The top of the lock head is provided with a lock hole for limiting the shackle and the top of the plug is provided with a promoting block which is outward raised. The bottom of the lock head is a helicoid and the promoting block withstands the helicoid. The plug is turned to facilitate the promoting block to move along the helicoid and the up-and-down movement of the lock head is realized, thereby causing the lock head to be locked up and separated from the shackle. The outer side of the lock head is covered with a return spring. The top of the return spring withstands the inner wall of the lock body and the bottom withstands the lock head. The dial lock can realize the separation of the shackle and the lock body automatically. When using a traditional key to unlock the lock, people can use the key to rotate the plug, the promoting block of the plug is caused to move along the helicoid of the lock head by the lock head under the promoting effect of the restoring force of the return spring and then the lock head moves down relative to the plug, thereby separating from the shackle. The shackle can be rotated freely to achieve the unlocking purpose. The dial lock has a simple structure and convenient and rapid operation.

The invention relates to an intelligent unlocking system and an intelligent unlocking method, wherein the unlocking system comprises a user terminal convenient for a user to operate and an intelligentlock mounted and fixed on a to-be-locked device, the user terminal realizes information interaction with the intelligent lock by a wireless network; the intelligent lock comprises a microprocessor, astorage module, an unlocking module and an alarm module; the microprocessor is used for verifying information sent by the user terminal according to the information of the storage module, and the alarm module is used for sending alarm information when information input by a users has an error. The intelligent lock disclosed by the invention can only be unlocked by sending instruction to a mobilephone or a computer terminal of the owner of the intelligent lock when unlocking is needed by storing the information of the owner of the intelligent lock, and thus the situation that a person with bad intention steals unlocking passwords or copies fingerprint to unlock can be avoided.

The invention relates to the field of locks, in particular to an anti-theft padlock and key assembly. The anti-theft padlock and key assembly comprises a key and a padlock. An unlocking device is arranged in the padlock. The unlocking device comprises an unlocking column (32), wherein the unlocking column (32) is coaxial with a lock cylinder tail (19) and is used for rotating and squeezing a second compression spring (14). A fifth hole (33) used for installing the unlocking column (32) is formed in a lock body (4). The fifth hole (33) communicates with a fourth hole (17). The unlocking column (32) is installed in the fifth hole (33). A gap is formed between the end, away from the second compression spring (14), of the unlocking column (32) and the lock cylinder tail (19). A second key hole (34) allowing a key body (2) to be inserted therein to drive the unlocking column (32) to rotate is further formed in the unlocking column (32). The anti-theft effect of the anti-theft padlock and key assembly is good.

The invention discloses a mechanical linkage antitheft lock and belongs to the technical field of locks. The mechanical linkage antitheft lock comprises a lock shell, an unlocking shift lever assembly, a main bolt assembly, an auxiliary bolt assembly and a lock cylinder assembly. The main bolt assembly comprises a main spring bolt, a main spring bolt column and a main spring bolt positioning base, and the main spring bolt column is provided with a limiting column. A locking block of the lock cylinder assembly abuts against the edge of the limiting column. The unlocking shift lever assembly comprises a shift lever shaft, a shift lever shaft sleeve and a shift lever handle. A spring bolt shift lever is connected to the middle of the shift lever shaft and abuts against the edge of the main spring bolt column, and the main spring bolt can retract inwards by wrenching the shift lever handle. The auxiliary bolt assembly comprises an upper spring bolt, a lower spring bolt, a pulley and a steel wire rope, one end of the steel wire rope is connected with the upper spring bolt and the lower spring bolt, the other end of the steel wire rope bypasses the pulley and is connected with the main spring bolt, and when the main spring bolt retracts inwards, the steel wire rope enables the upper spring bolt and the lower spring bolt to retract into the lock shell at the same time. According to the mechanical linkage antitheft lock, a linkage mechanism is simple, machining and assembling are convenient, operation is reliable, operation is convenient and flexible, multiple anti-prying and antitheft functions are achieved, and the antitheft lock can be effectively prevented from being unlocked violently by lawbreakers.

The invention provides an outward opening door lock for an elevator, and belongs to the technical field of the elevator. The outward opening door lock for the elevator comprises a bottom shell, a lock bolt, a lock rod arranged in the bottom shell, a moving point connecting piece, a quiescent point seat, a backward spinning piece, a rotating sleeve, a lifting piece, a driver and a detecting switch. The moving point connecting piece and the backward spinning piece are sleeved on the lock rod respectively, the two ends of the lock rod stretch out from the wall of the bottom shell to be connected with an unlocking piece and the lock bolt respectively, the moving point connecting piece is close to the outward opening lock piece end, a first elastic piece is arranged between the moving point connecting piece and the wall of the bottom shell, a moving point is arranged at one end of the moving point connecting piece, the detecting switch is fixed on the bottom shell, one end of the lifting piece is connected with the driver, and the other end of the lifting piece is matched with the backward spinning piece for moving. In a locking state, the moving point is connected with a quiescent point in a matched mode, wherein the quiescent point is fixed on the quiescent point seat, and the lifting piece makes contact with the detecting switch, and in an unlocking state, one end of the rotating sleeve makes contact with the backward spinning piece, and the power line of the detecting switch, the power line of the driver and the power line of the quiescent point seat are connected with an outer control cabinet. The structure which is linked by components and a two-way electromagnet are used for driving the outward opening door lock, therefore, unlocking and locking are achieved, the unlocking state and the locking state can be detected through the detecting switch, and the outward opening door lock for the elevator is simple in structure, convenient to assemble and low in cost.

The invention relates to a labor-saving touch trigger lock mechanism. The labor-saving touch trigger lock mechanism comprises a lock shell, a lock mounting plate, a lock tongue linkage assembly and a lock tongue tough trigger assembly, a guide rod of the lock shell is sleeved with a driven gear with an eccentric shaft hole, the front end of the lock tongue linkage assembly is fixedly provided with a center guide column and side guide columns, a touch trigger rod of the lock tongue touch trigger assembly right faces a releasing check block in the lock shell, and a convex shoulder of the releasing check block can triggered by the touch trigger rod to release or restrain moving. Locking and unlocking can be achieved. The mechanism is simple in structure, assembling is easy, and work is reliable.

The invention provides an outward opening door lock for an elevator, and belongs to the technical field of the elevator. The outward opening door lock for the elevator comprises a bottom shell, a lock bolt, a lock rod arranged in the bottom shell, a moving point connecting piece, a quiescent point seat, a backward spinning piece, a rotating sleeve, a lifting piece, a driver and a detecting switch. The moving point connecting piece and the backward spinning piece are sleeved on the lock rod respectively, the two ends of the lock rod stretch out from the wall of the bottom shell to be connected with an unlocking piece and the lock bolt respectively, the moving point connecting piece is close to the outward opening lock piece end, a first elastic piece is arranged between the moving point connecting piece and the wall of the bottom shell, a moving point is arranged at one end of the moving point connecting piece, the detecting switch is fixed on the bottom shell, one end of the lifting piece is connected with the driver, and the other end of the lifting piece is matched with the backward spinning piece for moving. In a locking state, the moving point is connected with a quiescent point in a matched mode, wherein the quiescent point is fixed on the quiescent point seat, and the lifting piece makes contact with the detecting switch, and in an unlocking state, one end of the rotating sleeve makes contact with the backward spinning piece, and the power line of the detecting switch, the power line of the driver and the power line of the quiescent point seat are connected with an outer control cabinet. The structure which is linked by components and a two-way electromagnet are used for driving the outward opening door lock, therefore, unlocking and locking are achieved, the unlocking state and the locking state can be detected through the detecting switch, and the outward opening door lock for the elevator is simple in structure, convenient to assemble and low in cost.

The invention discloses a coded lock with double dial plates. The coded lock comprises a shell consisting of an outer shell, an inner shell and a cover body, wherein the outer shell is provided with an accommodating chamber and a channel, the inner shell is arranged in the outer shell and is provided with a notched groove, and the cover body covers an opening of the accommodating chamber; a lock plunger group comprises a lock plunger, one end of the lock plunger extends to the interior of the accommodating chamber and is provided with a plunger clamping protruding part, and an elastic member is used for supplying elastic force to make the lock plunger move towards a direction opposite to the accommodating chamber; a first disc group is arranged in the accommodating chamber and comprises a shaft tube and a plurality of disc bodies coaxially arranged on the shat tube in parallel, and the periphery of each disc body is provided with a notch; a first dial plate is arranged at one side of the outer shell, opposite to the opening, and can be used for making the plurality of disc bodies of the first disc group rotate to make notches on the disc bodies be aligned to the notched groove in sequence; and the second disc group is arranged in the accommodating chamber and comprises a shaft and a plurality of disk bodies coaxially arranged on the shat in parallel, and the periphery of each disc body is provided with a notch; and a second dial plate is arranged at the outer side of the first dial plate. The coded lock disclosed by the invention has a favorable anti-theft effect on unlocking difficulty.

The invention discloses a clutch lock, comprising a lock body, a lock cylinder which is axially sleeved in the lock body and can rotate, and a clutch base, and the lock cylinder is provided with a plurality of blade marbles with V-shaped grooves along an axis, and the blade marbles are elastic. The lock cylinder and the clutch base are respectively provided with a locking side column which is cooperated with the V-shaped groove on the blade marble and has elasticity, and a clutch pin with a clamping handle. The end of the clutch pin is a wedge shape. The clamping handle of the clutch pin is between the locking side column and the lock body. The lock body is provided with a clamping groove matched with the clamping handle of the clutch pin, and a wedge-shaped clamping groove cooperated with the wedge-shaped end of the clutch pin. The lock body is internally provided with a clutch pin clamping bead which contacts with the clutch pin in a radial manner and has elasticity. Since the clutch pin with the clamping handle is used, when the lock cylinder rotates, the lock cylinder joins with the clutch base through the clamping handle of the clutch pin, so as to achieve an objective of unlocking. The structure can greatly improve reliability of clutch of the lock cylinder and the clutch base, and a problem that a lock cannot be opened is thoroughly solved.

A mechanical and fingerprinting dual-purpose handle lock comprises a front handle, wherein the front handle is provided with a sleeve A and a sleeve B which are mutually connected, and a fingerprint module is arranged on the sleeve A; the fingerprint module is connected with a lock body through a motor, and a lock cylinder is arranged in the sleeve B and connected with a clutch mechanism; the clutch mechanism comprises a rotating shaft, a clutch driving part B and magnetic elements arranged on the rotating shaft and the clutch driving part B; the rotating shaft can rotate forwards or reversely for 180 degrees; the clutch driving part B and the rotating shaft are attached or separated through magnetic field commutation. When a key is inserted into the lock cylinder and rotates for 180 degrees, a magnetic bead B on the rotating shaft and a magnetic bead A on a clutch driving part A can be separated or attached, when the magnetic bead A and the magnetic bead B are separated, the clutch driving part A can be downwards clamped with the clutch driving part B under the action of repellent acting force of the magnetic beads, and the unlocking purpose is achieved; when the magnetic bead A and the magnetic bead B are attached, the clutch driving part A and the clutch driving part B can be separated, and the locking state is realized at the moment.

The invention provides a safe electronic lock of a general lock cylinder, and relates to the field of electronic locks. The safe electronic lock comprises a key and the lock cylinder. A communicationend, a drive motor, an inner lock cylinder and an outer lock cylinder are arranged in the lock cylinder. Starting of the drive motor needs to obtain passing of encryption verification of the communication end. The drive motor pushes a lifting valve located in the inner lock cylinder, and therefore a fixed clamp retreats into the lifting valve. The output end of a shaft of the lifting motor is connected with a lifting valve control end in the outer lock cylinder. The lifting valve control end is located in a groove below a connecting buckle. The inner lock cylinder and the outer lock cylinder are rotated at the same time so as to rotate an unlocking driving lever, and the aim of unlocking is achieved. According to the safe electronic lock, unified general specifications are adopted, low-cost fast upgrading and replacement can be achieved, and the requirement of domestic and civil use is met; the drive motor can be started only by obtaining passing of encryption verification of serial and wireless Bluetooth at the same time, the inner lock cylinder and the outer lock cylinder are rotated at the same time through the drive motor so as to rotate the unlocking driving lever, and the aimof unlocking is achieved; and the safe electronic lock is safer.