Patent Publication Number: US-11391066-B2

Title: Electronic cabinet lock

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an electronic lock, and more particularly to an electronic cabinet lock. 
     2. Description of the Prior Art 
     An electronic cabinet lock generally includes a lock housing, a lock body, a limiting member and so on. The lock body and the limiting member are rotatably disposed in the lock housing. The lock body has an engaging groove configured to mate with a lock hook on a door. A detent structure is provided between the lock body and the limiting member for the limiting member to limit the lock body. A conventional electronic cabinet lock uses an electromagnetic mechanism to control the swing of the limiting member for releasing the lock body to open the door. However, the electronic cabinet lock using the electromagnetic mechanism consumes much power because the electromagnetic mechanism needs to be driven by large current. When the electronic cabinet lock using the electromagnetic mechanism is applied to a cabinet with multiple cabinet bodies, it is necessary to mount the electronic cabinet lock using the electromagnetic mechanism on each cabinet body. In order to reduce energy consumption, only a single cabinet body is used for opening the door, which is inconvenient for use. Thus, an improved electronic cabinet lock uses a motor in cooperation with a mechanical transmission mechanism to control the swing of the limiting member. This electronic cabinet lock driven by the motor has the characteristics of small current, low cost, and low damage. However, this electronic cabinet lock also has the following disadvantages. The motor is controlled by a mechanical transmission mechanism composed of a gear reduction group, a push rod and the like to control the swing of the limiting member. The mechanical transmission mechanism has many components and complicated structures. As a result, it is troublesome to assemble the mechanical transmission mechanism. Moreover, the mechanical failure rate of the mechanical transmission mechanism is high in use, which affects the use of the electronic cabinet lock greatly. 
     Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve these problems. 
     SUMMARY OF THE INVENTION 
     The primary object of the present invention is to provide an electronic cabinet lock, and its transmission mechanism has a simple structure and is convenient for assembly. 
     In order to achieve the above object, the present invention adopts the following technical solutions: 
     An electronic cabinet lock comprises a lock housing, a lock body, a limiting member, a motor, and a main control board. The lock body and the limiting member are rotatably disposed in the lock housing, respectively. A first elastic member for returning the lock body is disposed between the lock body and the lock housing. The lock body is provided with an engaging groove configured to mate with a lock hook on a door. A detent structure is provided between the lock body and the limiting member for the liming member to limit the lock body. The motor is electrically connected to the main control board. The limiting member is driven by the motor through a transmission mechanism. The transmission mechanism includes a slider and a screw rod. The slider is slidably disposed in the lock housing through a sliding guide structure, and is movably connected to the limiting member. The screw rod is driven to rotate by the motor. The screw rod is threadedly connected to the slider for driving the slider to slide. 
     Preferably, the limiting member has a predetermined movable space relative to the slider. The limiting member is driven by the motor and the transmission mechanism to rotate so as to release the lock body. A second elastic member for returning the limiting member is disposed between the limiting member and the lock housing. 
     Preferably, the slider is provided with an elongate hole in a longitudinal direction along a sliding direction of the slider. The limiting member is provided with a rod. The rod is slidably connected to the elongate hole. 
     Preferably, the lock housing is provided with an emergency unlocking hole for manually rotating the limiting member to release the lock body. 
     Preferably, the emergency unlocking hole is a first through hole that is formed on the lock housing and corresponds in position to an end of the limiting member. 
     Preferably, a free end of the rod extends out of the elongate hole. The emergency unlocking hole is a second through hole that is formed on the lock housing and corresponds in position to the free end of the rod. 
     Preferably, one end of the slider is threadedly connected to the screw rod. Another end of the slider is provided with a perforation communicating with the elongate hole and extending along the sliding direction of the slider. The emergency unlocking hole is a third through hole that is formed on the lock housing and corresponds to the perforation. 
     Preferably, the lock body is provided with a ball. The lock housing is provided with a limiting portion to cooperate with the ball. When the lock body is rotated to a locked position, the ball abuts against the limiting portion and restricts the first elastic member from driving the lock body to be returned. 
     Preferably, the electronic cabinet lock further comprises a first switch mechanism controlled by the lock body and a second switch mechanism controlled by the limiting member. The first switch mechanism and the second switch mechanism are electrically connected to the main control board for controlling a working state of the motor. 
     Preferably, the first switch mechanism is a micro switch that is activated when the lock body is rotated to a locked position, and the micro switch is disposed in the lock housing. Alternatively, the first switch mechanism is a first Hall switch that includes a first magnet disposed on the lock body and a first magnetic field detecting part electrically connected to the main control board. When the lock body is rotated to the locked position, the first magnetic field detecting part detects a magnetic field of the first magnet. 
     Preferably, the second switch mechanism is a micro switch that is activated when the limiting member is rotated to a position where the lock body is released, and the micro switch is disposed in the lock housing. Alternatively, the second switch mechanism is a second Hall switch that includes a second magnet disposed on the limiting member and a second magnetic field detecting part electrically connected to the main control board. When the limiting member is rotated to the position where the lock body is released, the second magnetic field detecting part detects a magnetic field of the second magnet. 
     Preferably, the detent structure includes a first detent portion disposed on the lock body and a second detent portion disposed on the limiting member. The first detent portion is movably engaged with the second detent portion. 
     Preferably, the sliding guide structure includes a guide rail disposed on the slider and a sliding groove disposed on the lock housing. The guide rail and the sliding groove are disposed along the sliding direction of the slider and are slidably mated with each other. The screw rod is coaxially connected to an output shaft of the motor. 
     Preferably, the lock body is rotatably sleeved on a first rotating shaft of the lock housing. The first elastic member is a first torsion spring. A spiral portion of the first torsion spring is sleeved on the first rotating shaft. Two ends of the first torsion spring lean against the lock body and the lock housing, respectively. The limiting member is rotatably sleeved on a second rotating shaft of the lock housing. The second elastic member is a second torsion spring. A spiral portion of the second torsion spring is sleeved on the second rotating shaft. Two ends of the second torsion spring lean against the limiting member and the lock housing, respectively. 
     Compared with the prior art, the present invention has the following beneficial effects: 
     1. The transmission mechanism of the present invention includes the slider and the screw rod. The slider is slidably disposed in the lock housing through the sliding guide structure, and is movably connected to the limiting member. The screw rod is driven to rotate by the motor. The screw rod is threadedly connected to the slider for driving the slider to slide. Therefore, the transmission mechanism of the present invention has fewer components and a simpler structure. The structure is simpler, the assembly is easier, and the mechanical failure rate is lower. 
     2. The motor of the invention is connected with the limiting member through the transmission mechanism, and the invention further comprises an emergency unlocking structure. Specifically, the limiting member has a predetermined movable space relative to the slider. The lock housing is provided with the emergency unlocking hole for manually rotating the limiting member to release the lock body. In this way, one can release the lock body by using a tool to pass through the emergency unlocking hole for driving the limiting member to rotate, thereby performing manual unlocking. 
     3. The arrangement of the ball and the limiting portion of the present invention enables the present invention to restrict the first elastic member from driving the lock body to be returned after the limiting member releases the lock body. Therefore, the lock body is held in the locked position to keep the lock hook in the engaging groove of the lock body, so as to keep the door from being opened. At this time, the door needs to be pulled by hand to open the door. The invention may be applied to some cabinets (such as cabinet freezers, refrigerated cabinets, etc.) that need to reduce the time when the cabinets are in an open state. In particular, when the present invention in cooperation with a door closer is applied to such a cabinet, the effect is better. In addition, the arrangement of the ball and the limiting portion can restrict the first elastic member from driving the lock body to be returned when the door is closed, that is, when the lock hook pushes the lock body to the locked position. Thereby, the motor and the transmission mechanism have sufficient time to drive the limiting member to limit the lock body so as to complete the locking. 
     4. Through the arrangement of the first switch mechanism and the second switch mechanism, the invention is more intelligent and convenient to operate to facilitate the function expansion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view of a first embodiment of the present invention; 
         FIG. 2  is a partial schematic view of the first embodiment of the present invention in a locked state; 
         FIG. 3  is a partial schematic view of the first embodiment of the present invention in an unlocked state; 
         FIG. 4  is perspective view of the first embodiment of the present invention; 
         FIG. 5  is a schematic view of the slider of the present invention; 
         FIG. 6  is a partial schematic view of the first embodiment of the present invention; 
         FIG. 7  is a cross-sectional view taken along line A-A of  FIG. 6 ; 
         FIG. 8  is a schematic view of the first embodiment of the present invention applied to a cabinet; 
         FIG. 9  is an enlarged view of circle B of  FIG. 8 ; 
         FIG. 10  is an enlarged view of circle C of  FIG. 8 ; 
         FIG. 11  is an enlarged view of circle D of  FIG. 8 ; and 
         FIG. 12  is a partial schematic view of a first embodiment of the present invention in a locked state. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings. 
     Referring to  FIG. 1  to  FIG. 12 , the present invention discloses an electronic cabinet lock. The electronic cabinet lock comprises a lock housing  1 , a lock body  2 , a limiting member  3 , a motor  4 , and a main control board  5 . The lock body  2  and the limiting member  3  are rotatably disposed in the lock housing  1 , respectively. A first elastic member for returning the lock body  2  is disposed between the lock body  2  and the lock housing  1 . The lock body  2  is provided with an engaging groove  21  configured to mate with a lock hook  9  on a door. A detent structure is provided between the lock body  2  and the limiting member  3  for the liming member  3  to limit the lock body  2 . The motor  4  is electrically connected to the main control board  5 . The limiting member  3  is driven by the motor  4  through a transmission mechanism  6 . The transmission mechanism  6  includes a slider  62  and a screw rod  61 . The slider  62  is slidably disposed in the lock housing  1  through a sliding guide structure, and is movably connected to the limiting member  3 . The screw rod  61  is driven to rotate by the motor  4 . Specifically, the screw rod  61  is coaxially connected to an output shaft of the motor  4 . The screw rod  61  is threadedly connected to the slider  62  for driving the slider  62  to slide. 
     The limiting member  3  has a predetermined movable space relative to the slider  62 . Specifically, the slider  62  is provided with an elongate hole  621  in a longitudinal direction along a sliding direction of the slider  62 . The limiting member  3  is provided with a rod  7 . The rod  7  is slidably connected to the elongate hole  621 . A free end  71  of the rod  7  extends out of the elongate hole  621 . Specifically, the rod  7  is a cap screw screwed to the limiting member  3 , but not limited thereto. The limiting member  3  is driven by the motor  4  and the transmission mechanism  6  to rotate for releasing the lock body  2 . A second elastic member for returning the limiting member  3  is disposed between the limiting member  3  and the lock housing  1 . 
     The lock body  2  is provided with a ball  8 . The lock housing  1  is provided with a limiting portion to cooperate with the ball  8 . Specifically, the limiting portion is a limiting post  12 . When the lock hook  9  is engaged in the engaging groove  21  of the lock body  2 , the ball  8  abuts against the limiting post  12  and restricts the first elastic member from driving the lock body  2  to be returned. 
     The detent structure includes a first detent portion  22  disposed on the lock body  2  and a second detent portion  31  disposed on the limiting member  3 . The first detent portion  22  is movably engaged with the second detent portion  31 . 
     The lock body  2  is rotatably sleeved on a first rotating shaft  15  of the lock housing  1 . The limiting member  3  is rotatably sleeved on a second rotating shaft  16  of the lock housing  1 . The first detent portion  22  and the engaging groove  21  are located at opposite two ends of the lock body  2 . The ball  8  and the engaging groove  21  are located at the same end of the lock body  2 . The lock housing  1  is provided with a notch  13  corresponding in position to the engaging groove  21  for the lock hook on the door to pass therethrough. The second detent portion  31  is located at a side of one end of the limiting member  3 . The rod  7  is connected to the other end of the limiting member  3 . 
     The sliding guide structure includes a guide rail  622  disposed on the slider  62  and a sliding groove  14  disposed on the lock housing  1 . The guide rail  622  and the sliding groove  14  are disposed along the sliding direction of the slider  62  and are slidably mated with each other. Specifically, the lock housing  1  may be composed of an upper housing  101  and a lower housing  102 . The upper housing  101  and the lower housing  102  each have the sliding groove  14  at corresponding positions. The upper and lower surfaces of the slider  62  are provided with the guide rails  622  to mate with the corresponding sliding grooves  14 . 
     The present invention further includes a first switch mechanism controlled by the lock body  2  and a second switch mechanism controlled by the limiting member  3 . The first switch mechanism and the second switch mechanism are electrically connected to the main control board  5  for controlling the working state of the motor  4 . As shown in  FIG. 1  to  FIG. 5 , in a first embodiment of the present invention, the first switch mechanism is a micro switch that is activated when the lock body  2  is rotated to a locked position. The micro switch is disposed on the lock housing  1 . For convenience of explanation, the micro switch is defined as a first micro switch a. The second switch mechanism is a micro switch that is activated when the limiting member  3  is rotated to a position where the lock body  2  is released. The micro switch is disposed on the lock housing  1 . For convenience of explanation, the micro switch is defined as a second micro switch b. 
     The first elastic member is a first torsion spring c. A spiral portion of the first torsion spring c is sleeved on the first rotating shaft  15 . Two ends of the first torsion spring c lean against the lock body  2  and the lock housing  1 , respectively. A spiral portion of the second torsion spring d is sleeved on the second rotating shaft  16 . Two ends of the second torsion spring d lean against the limiting member  2  and the lock housing  1 , respectively. 
     The electronic cabinet lock of the invention has a locked state and an unlocked state. The locked state is as shown in  FIG. 2 . The lock body  2  is in the locked position, the lock hook  9  is engaged in the engaging groove of the lock body  2 , the second detent portion  31  of the limiting member  3  is engaged with the first detent portion  22  of the lock body  2 , and the ball  8  is pressed against the side of the limiting post  12 . The first elastic member is in an energy storage state, and the second elastic member is in a return state. The rod  7  on the limiting member  3  leans against the left end of the elongate hole  621 . When the unlocking is required, the main control board  5  is given a command (the command may be a WiFi command, a scanning two-dimensional code command, a manual pressing command, etc., which is the prior art), so that the main control board  5  controls the motor  4  to start. The motor  4  drives the screw rod  61  to rotate in the forward direction. Because the screw rod  61  is threadedly connected to the slider  62 , as the screw rod  61  rotates in the forward direction, the slider  62  slides to the right to drive the limiting member  3  to swing a certain angle in a clockwise direction (relative to the viewing angle of  FIG. 1 ), so that the second detent portion  31  of the limiting member  3  is disengaged from the first detent portion  22  of the lock body  2  to release the lock body  2  while the second elastic member is in an energy storage state. At this time, the door can be opened. But, since the ball  8  is held against the limiting post  12 , the lock body  2  is kept in the locked position. The lock hook is still in the engaging groove  21  of the lock body  2 , so the door will not open automatically. When the user opens the door, the lock hook  9  drives the lock body  2  to rotate a certain angle to disengage the ball  8  from the limiting post  12 . Thereafter, the lock hook  9  is disengaged from the lock body  2  to open the door, and the lock body  2  is rotated to the unlocked position by the restoring force of the first elastic member, as shown in  FIG. 3 . During the above unlocking process, when the limiting member  3  is rotated clockwise in place, the second micro switch b is activated, and the second micro switch b generates a signal to the main control board  5 , so that the main control board  5  controls the motor  4  to stop rotating. 
     When the door is to be closed, the door is pushed for the lock hook  9  on the door to engage with the engaging groove  21  of the lock body  2 . During this process, the lock hook  9  pushes the lock body  2  to overcome the elastic force of the first elastic member and rotate to the locked position, and the lock body  2  touches the first micro switch a. The first micro switch a generates a signal to the main control board, so that the main control board  5  activates the motor  4 . The motor  4  drives the screw rod  61  to rotate reversely, so that the slider  62  slides to the left to release the rod  7 , and the second elastic member releases energy to drive the limiting member  3  to rotate counterclockwise to the position where the lock body  2  is limited, as shown in  FIG. 2 . 
     Since the limiting member  3  has a predetermined movable space relative to the slider  62 , the limiting member  3  is driven by the motor  4  and the transmission mechanism  6  to rotate so as to release the lock body  2 . Thus, the lock housing  1  may be provided with an emergency unlocking hole  11  for manually rotating the limiting member  3  to release the lock body  2 . In the case of power failure or in the case when the main control board  5  or the motor  4  is damaged, one can release the lock body  2  by using a tool to pass through the emergency unlocking hole  11  for driving the limiting member  3  to rotate, thereby performing manual unlocking. The tool may be a screwdriver or a hex wrench. Specifically, the lock housing  1  has three emergency unlocking holes  11 . The first emergency unlocking hole is a first through hole  111  that is formed on the lock housing  1  and corresponds in position to the end of the limiting member  3 . The second emergency unlocking hole is a second through hole  112  that is formed on the lock housing  1  and corresponds in position to the free end  71  of the rod  7 . One end of the slider  62  is threadedly connected to the screw rod  61 , and another end of the slider  62  is provided with a perforation  623  communicating with the elongate hole  621  and extending along the sliding direction of the slider  62 . The third emergency unlocking hole is a third through hole  623  that is formed on the lock housing  1  and corresponds to the perforation  623 . When the present invention is mounted to a cabinet G, the cabinet G is provided with an opening corresponding to the first through hole  111  or the second through hole  112 . In this way, the tool can pass through the opening and the first through hole  111  from the outside the cabinet G to rotate the limiting member  3  for releasing the lock body  2 , or the tool can pass through the opening and the second through hole  112  to rotate the limiting member  3  for releasing the lock body  2 , thereby performing manual unlocking. As shown in  FIG. 8  to  FIG. 11 , in the case that the cabinet is provided with at least one row of compartments. Each row of compartments includes at least two compartments G. The electronic cabinet lock of the present invention is mounted to each compartment G of each row of compartments and disposed on the same side. The side wall having the first through hole  111  of the lock housing  1  of each electronic cabinet lock is connected to the side wall of the compartment G. The cabinet is provided with a movable emergency lever F corresponding to each row of compartments. The emergency lever F on each row of compartments is provided with a plurality of push blocks F 1  corresponding to the electronic cabinet locks of the row of compartments. Each push block F 1  of the emergency lever F of each row of compartments is inserted into the first through holes  111  of each electronic cabinet lock of the row of compartments. In this way, by moving the emergency lever F of each row of compartments, each push block F 1  of the emergency lever F of each row of compartments can be used to push the limiting member  3  of each electronic cabinet lock of the row of compartments, thereby unlocking multiple electronic cabinet locks at a time. As shown in FIG.  8  and  FIG. 11 , a tool T may be disposed in the compartment G. Thus, if one is accidentally locked in the compartment G, at this time, one can use the tool T in the compartment G to rotate the limiting member  3  by using the tool T to pass through the second through hole  112  or the third through hole  113  for releasing the lock body  2 , thereby performing manual unlocking. In order to facilitate the user to find the tool T in the compartment G, the compartment G may be provided with a lamp M. 
     In summary, the electronic cabinet lock of the present invention uses the transmission mechanism composed of the slider and the screw rod as a transmission assembly between the motor and the limiting member. Compared with the prior art that adopts a mechanical transmission mechanism composed of a gear reduction group, a push rod and so on. The transmission mechanism of the present invention has fewer components and is a simple structure. The assembly is easier, and the mechanical failure rate is lower. The arrangement of the ball  8  and the limiting portion of the present invention enables the present invention to restrict the first elastic member from driving the lock body  2  to be returned after the limiting member releases the lock body. Therefore, the lock body  2  is held in the locked position to keep the lock hook in the engaging groove  21  of the lock body  2 , so as to keep the door from being opened. The door needs to be pulled by hand to open the door. The invention may be applied to some cabinets (such as cabinet freezers, refrigerated cabinets, etc.) that need to reduce the time when the cabinets are in an open state. In particular, when the present invention in cooperation with a door closer is applied to such a cabinet, the effect is better. In addition, the arrangement of the ball  8  and the limiting portion can restrict the first elastic member from driving the lock body  2  to be returned when the door is closed, that is, when the lock hook pushes the lock body  2  to the locked position. Thereby, the motor  4  and the transmission mechanism  6  have sufficient time to drive the limiting member  3  to limit the lock body  2  so as to complete the locking. 
     It should be noted that, in a second embodiment of the present invention, the first switch mechanism is a first Hall switch a′, including a first magnet a 1 ′ disposed on the lock body  2  and a first magnetic field detecting part a 2 ′ electrically connected to the main control board  5 . When the lock body  2  is rotated to the locked position, the first magnetic field detecting part a 2 ′ detects the magnetic field of the first magnet a 1 ′ and transmits a signal to the main control board  5 . In the second embodiment of the present invention, the second switch mechanism is a second Hall switch b′, including a second magnet b 1 ′ disposed on the limiting member  3  and a second magnetic field detecting part b 2 ′ electrically connected to the main control board  5 . When the limiting member  3  is rotated to the position where the lock body  2  is released, the second magnetic field detecting part b 2 ′ detects the magnetic field of the second magnet b 1 ′ and transmits a signal to the main control board  5 . 
     Although particular embodiments of the present invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the present invention. Accordingly, the present invention is not to be limited except as by the appended claims.