Patent Publication Number: US-11661763-B2

Title: Anti-unlatched mechanism and a door lock thereof

Description:
PRIORITY CLAIMS AND INCORPORATION OF RELATED APPLICATIONS 
     This application claims priority to the following three Chinese applications, and incorporate by reference their related pending US applications in their entireties: 
     (A) Chinese application 202010622272.0, filed Jul. 1, 2020; 
     (B) Chinese application 202010619727.3, filed Jul. 1, 2020 and U.S. Ser. No. 17/249,308, filed Feb. 26, 2021, MVS Ref No. P13400US00; 
     (C) Chinese application 202011060664.9, filed Sep. 30, 2020, and U.S. Ser. No. 17/249,326, filed Feb. 26, 2021, MVS Ref No. P13401US00; and 
     (D) Chinese application 202010622790.2, filed Jul. 1, 2020, and U.S. Ser. No. 17/249,299, filed Feb. 26, 2021, MVS Ref No. P13437US00. 
     FIELD OF THE INVENTION 
     The present disclosure relates to the technical field of locks, specially relates to an anti-unlatched mechanism and a door lock thereof. 
     BACKGROUND OF THE INVENTION 
     A multi-point lock with shootbolts is a lock capable of extending both upper and the lower shootbolts (i.e. the corresponding top lock and bottom lock) out of the door when being locked up. The multi-point lock with top lock and bottom lock works in the following principle: when opening a locked door, turn the lock cylinder with a key on the outside of the door or thumb drive or turn on the inside of the door to withdraw the deadbolt, and then press the lever handle down to withdraw the latch bolt and the upper and the lower shootbolts simultaneously, such that the door can be opened. After the lever handle is released, the latch bolt will extend, and the lever handle will return to its original position. When locking a closed door, raise the lever handle at a certain angle to extend the upper and the lower shootbolts, and then use a key or a thumb turn cylinder in the room to turn the cylinder to extend the deadbolt, thereby locking the door. After the lever handle is released, the lever handle will return to the original position. When the door is locked by the upper and the lower shootbolts, deadlatch and the latch bolt, the safety is well improved. 
     However, there is a unlatch phenomenon for the existing multi-point lock when extending the upper and lower shootbolts. That is, the shootbolts do not fully extend when the lever handle is raised, enabling the shootbolts to withdraw by only pressing down lever handle, which greatly reduce the safety of the door lock and degrade the user&#39;s experience. 
     SUMMARY OF THE INVENTION 
     In order to overcome the above-mentioned drawbacks of the prior art, an object of the present invention is to provide an anti-unlatched mechanism and a door lock thereof, which effectively assure a lock state of the upper and lower locking shootbolts when the door is in a locked state, thereby greatly improving the safety of the door lock and the user&#39;s experience. 
     The present invention adopts the following technical solution to solve its technical problem: 
     An anti-unlocked mechanism comprising a transmission gear, a sliding rod, a locking member and a first elastic member, all provided in the lock body; 
     The transmission gear is engaged with the rotating part in the lock body for driving the upper shootbolt and the lower shootbolt of the lock body to lock/unlock a door, wherein the rotating part is used for installing the lever handle. The outer peripheral surface of the transmission gear is comprised of a circular arc surface and a plurality of gear teeth, and a distance from the circular arc surface to the center of the rotation shaft of the transmission gear is greater than a distance from the tooth crest of the transmission gear to the center of the rotation shaft of the transmission gear; 
     The sliding rod is arranged in the lock body and may slide relative to the lock body, with an end of the sliding rod being in contact with the latch bolt of the lock body. The sliding rod is provided with a fixed stopper and a second elastic member. When the deadbolt is retracted, the sliding rod moves with the deadbolt against the elastic force of the second elastic member; 
     The locking member interacts with the sliding rod, and when the deadbolt extends, the locking member moves with the sliding rod to block the rotating movement of the rotating part. 
     The first elastic member comprises a first protrusion for contacting with the circular arc surface, and a second protrusion for contacting with the fixed stopper. The second protrusion will not hinder the fixed stopper to slide with the sliding rod unless the first protrusion is in contact with the circular arc surface, which will block the movement of the locking member to block the rotating movement of the rotating part. 
     As preferred, an oblique guide surface is provided at the contact point between the sliding rod and the bolt. 
     As preferred, the locking member comprises a first side part and a second side part connected at an angle and a positioning post on the connection of the first side part and the second side part, and the locking member in the lock body may swing via the positioning post. 
     As preferred, a pair of limiting posts are provided on the sliding rod, and a space is formed between the pair of the limiting posts; 
     The first side part is clamped by, or received between, the limiting posts in the space, enabling the locking member to swing as the sliding rod slides; the rotating part is fixed with a protruding block, and when the second elastic member is in a natural state, the second side part swings beneath the rotational path of the block and abuts against the block. 
     As preferred, when the second elastic member is in a natural state, the extension cord of the second side part is tangent to the rotational path of the block. 
     As preferred, the first protrusion and the second protrusion of the first elastic member protrude in opposite directions. 
     As preferred, the rotating part includes a body and a plurality of driving toothed pieces rotatably arranged relative to the body. 
     The body is provided with a mounting hole for installing lever handle, and a third elastic member is provided between the body and the lock body for restoring the body after it rotates. 
     The transmission gear is coaxially provided with a driven gear, and the driving toothed piece is engaged with the driven gear. 
     As preferred, the upper shootbolt is provided with a first rack at the end extending into the lock body, and the lower shootbolt is provided with a second rack at the end extending into the lock body, and a synchronous gear engaged with the first rack and the second rack is arranged therebetween; 
     The transmission gear is engaged to the first rack or the second rack. 
     As preferred, the body is provided with a mounting groove for mounting the third elastic member, a first opening, and a second opening staggered with the first opening, wherein both openings are in communication with the mounting groove. 
     The third elastic member extends with two ends across the first opening and the second opening, respectively and abut against both sides of the fixed structure of the lock body, respectively. 
     A door lock includes the anti-unlocked mechanism described above. 
     Compared with the prior art, the beneficial effects of the present invention are: 
     The solution includes a transmission gear, a first elastic member and a sliding rod, and the sliding rod is provided with a fixed stopper and a locking member interacts with the sliding rod, and a circular arc surface is arranged on the transmission gear, so that when the lock body is being locked, for example when the lever handle is raised, the rotating part drives the transmission gear to rotate, and the transmission gear drives the upper and lower shootbolts to extend and lock. During the locking process, as the deadbolt abutting against the sliding rod is in the extended state, the second elastic member will return to its natural state, driving the sliding rod to restore to a raised or natural position. If the locking is successfully performed at this moment, the locking member will move until it abuts against the rotating part, so that the lever handle will be prevented from being pressed down, thereby the user can be aware of the information that the lock is in place; if the shootbolts are not fully extended and the lock is unlatched at this time, the circular arc surface will be abutting against the first protrusion of the first elastic member, so that the second protrusion will be abutting against the fixed stopper to prevent the locking member from swinging to block the movement of the rotating part, allowing the lever handle to be pressed down, thereby the user realizes that the lock body is unlocked. In this situation, the lock body can be locked again by merely raising the lever handle to pass the first protrusion out of the contact with the circular arc surface. This invention provides a compact structure with ingenious design which determines whether a lock is in an unlock state effectively by mutual linkage between the parts, by which the unlock problem is also solved, and the entire operation is simple and convenient, which greatly improves the safety of the door lock and the user&#39;s experience. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For better illustrating the technical solution of the embodiments of the present disclosure, the figures used for describing the embodiments will be briefly described below. Obviously, the figures described in the following are some embodiments of the present disclosure. For those skilled in the art, other figures can be obtained on the basis of these figures without any creative work. 
         FIG.  1    is a side elevation view showing the internal structure of a door lock of the present invention in an unlocked state. 
         FIG.  2    is an enlarged view of structure in Circle A of  FIG.  1   . 
         FIG.  3    is a side elevation view illustrating the internal structure of the present invention in a locked state. 
         FIG.  4    is an enlarged view of structure in Circle B of  FIG.  2   . 
         FIG.  5    is a perspective view of the sliding rod of the present invention. 
         FIG.  6    is a perspective view of the rotating part of the present invention. 
         FIG.  7    is a perspective view illustrating the structure of the door lock according to the present invention. 
     
    
    
     Wherein:
       1 —lock body,     11 —transmission gear,     111 —circular arc surface,     12 —sliding rod,     121 —fixed stopper,     122 —second elastic member,     123 —guide surface,     124 —limiting posts,     13 —locking member,     131 —first side part,     132 —second side part,     133 —positioning post,     14 —first elastic member,     141 —first protrusion,     142 —second protrusion,     15 —rotating part,     151 —block,     152 —body,     1521 —mounting hole,     1522 —mounting groove,     1523 —first opening,     1524 —second opening,     153 —driving tooth,     16 —upper shootbolt,     161 —first rack,     17 —lower shootbolt,     171 —second rack,     18 —deadbolt,     19 —third elastic member,     20 —synchronous gear.   

     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     For better understanding of the above objects, features and advantages of the present invention, the present invention will be described in detail below with reference to the drawings and specific embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict. In the following description, many specific details are set forth in order to fully understand the present invention. The described embodiments are only a part of the embodiments of the present invention, but not all the embodiments. Based on the embodiments in the present invention, any other embodiments obtained by those skilled in the art, without making any creative work, will fall within the protection scope of the present invention. 
     All technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of the present invention unless otherwise defined. The terminology used herein is for describing the specific embodiments, and is not intended to limit the present invention. 
     Example 1 
     As shown in  FIGS.  1 - 7   , this embodiment provides an anti-unlocked mechanism comprising a transmission gear  11 , a sliding rod  12 , a locking member  13  and a first elastic member  14 , all provided in a lock body  1 . 
     Specifically, the transmission gear  11  is engaged with the rotating part  15  in the lock body  1  for driving the upper shootbolt  16  and the lower shootbolt  17  of the lock body  1  to lock/unlock a door, and a lever handle is mounted on the rotating part  15 . The outer peripheral surface of the transmission gear  11  is comprised of circular arc surface  111  and a plurality of gear teeth, and a distance from the circular arc surface  111  to the center of the rotation shaft of the transmission gear  11  is greater than a distance from the tooth crest of the transmission gear  11  to the center of the rotation shaft of the transmission gear  11 , thereby enabling the circular arc surface  111  and the first elastic member  14  to be effectively contacted. In this embodiment, the arc length of the circular arc surface  111  is corresponds to the extension length or distance of the upper shootbolt  16  and the lower shootbolt  17  when being locked. The distance of the unlocked state is controlled by regulating or adjusting the arc length of the circular arc surface  111 . In other words, the length of the arc surface  111  corresponds to or matches the distance the upper and lower shootbolts  16 ,  17  extend and retract between the locked and unlocked conditions. 
     The sliding rod  12  is arranged in the lock body  1  and may slide relative to the lock body  1 . The upper end of the sliding rod  12  is in contact with the bolt  18  of the lock body  1  for pressing against the bolt  18 . The sliding rod  12  is also provided with a fixed stopper  121  between the ends, and a second elastic member  122  at the lower end. When the bolt  18  is retracted, the sliding rod  12  is pushed downwardly by the bolt  18 , against the elastic force of the second elastic member  122 . 
     In this embodiment, the bolt  18  in contact with the sliding rod  12  is configured as a deadbolt One end of the sliding rod  12  is in contact with the deadbolt  18 , and the other end of the sliding rod  12  is arranged with a second elastic member  122 , wherein the second elastic member  122  is configured as a spring. Alternatively, the second elastic member  122  can also be configured at the end in contact with the deadbolt  18 , in which case the second elastic member  122  is selected as a tension spring. 
     As a preferred solution, an oblique guide surface  123  is provided on the sliding rod  12  at the contact between the sliding rod  12  and the bolt  18 . In this embodiment, the guide surface  123  is provided at the end of the sliding rod  12  for smoothly pressing down the sliding rod  12  when the bolt  18  is retracted. Alternatively, it is possible to provide the guide surface  123  on the bolt  18 , rather than on the sliding rod  12 . 
     The locking member  13  is engaged with the sliding rod  12 , and when the bolt  18  extends, the second elastic member  122  will return to its natural state to slide the sliding rod  12 , driving the locking member  13  to move until blocking the rotating movement of the rotating part  15 , and thus block rotation of the handle connected to the rotating part  15 . 
     As a preferred solution, the locking member  13  comprises a first side part  131  and a second side part  132  connected at an angle and a positioning post  133  on the connection of the first side part  131  and the second side part  132 , thereby the locking member forms an L-shaped or a V-shaped configuration in a side view, and the locking member  13  in the lock body  1  may swing or rotate via the positioning post  133 . 
     In addition, a pair of limiting posts  124  are provided on the sliding rod  12 , and a space is formed between the pair of limiting posts  124 . The first side part  131  is received or clamped between the limiting posts  124  in the space, enabling the locking member  13  to pivot as the sliding rod  12  slides. Specifically, the rotating part  15  is provided with an extending block  151 , and when the second elastic member  122  is in a natural state, the locking member  13  moves upwardly with the sliding rod  12 , so that the second side part  132  swings beneath the rotational path of the block  151  until abuts against the block  151  to block the rotation of the rotation portion  15 . In this embodiment, the limiting posts  124  are each formed as a cylinder for coordinate movement between the sliding rod  12  and the locking member  13 . 
     As a preferred solution, when the second elastic member  122  is in a natural state, the extension cord of the second side part  132  is tangent to the rotational path of the block  151 . In case that the lever handle is pressed too hard, causing the locking member  13  rotate reversely to slide the sliding rod  12  to open the lock, which further improves the stop protection of the rotating part  15 . Therefore, the reliability of the mechanism is further improved, and the life time of the parts are extended as mis-operation is avoided. 
     The first elastic member  14  comprises a first protrusion  141  for contacting with the circular arc surface  111 , and a second protrusion  142  for contacting with the fixed stopper  121 , wherein the first protrusion  141  and the second protrusion  142  protrude in opposite directions. The second protrusion  142  will not hinder the fixed stopper  121  to slide with the sliding rod  12 , unless the first protrusion  141  is in contact with the circular arc surface  111 , which will block the movement of the locking member  13  to block the rotating movement of the rotating part  15 . 
     Further, the rotating part  15  includes a body  152  and a plurality of driving teeth  153  rotating relative to the body  152 , and the block  151  is arranged on the body  152 . The body  152  is provided with a mounting hole  1521  for installing a lever handle (not shown). In this embodiment, the cross section of the mounting hole  1521  is preferably configured in the form of a polygon. A third elastic member  19  is provided between the body  152  and the lock body  1  for restoring the body  152  after it rotates. The transmission gear  11  is coaxially provided with a driven gear, and one of the driving toothed pieces  153  is engaged with the driven gear. 
     As a preferred solution, the upper shootbolt  16  is provided with a first rack  161  at the end extending into the lock body  1 , and the lower shootbolt  17  is provided with a second rack  171  at the end extending into the lock body  1 , and a synchronous gear  20  engaged with the first rack  161  and the second rack  171  and is arranged therebetween. The transmission gear  11  is engaged to the first rack  161  or to the second rack  171 . 
     In addition, the body  152  is provided with a mounting groove  1522  for mounting the third elastic member  19 , a first opening  1523 , and a second opening  1524  staggered with the first opening, wherein both openings are in communication with the mounting groove  1522 . In this embodiment, the third elastic member  19  is a torsion spring. The third elastic member  19  extend with two ends across the first opening  1523  and the second opening  1524 , respectively and abut against both sides of the fixed structure of the lock body  1 , respectively. 
     In this embodiment, a door lock comprising the lock body  1  and the anti-unlocked mechanism described above is also provided. 
     For other structural forms of the door lock described in this embodiment, please refer to the prior art, which will not be repeated here. 
     The above is only the preferred embodiments of the present invention and does not limit the present invention in any form, so any modification, equivalent changes or replacements to the above embodiments, based on the technical essence of the present invention, without departing from the technical solution content of the present invention, are still within the scope of the technical solution of the present invention.