Patent Document

BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to locks and more particularly, to a padlock, which has two combination lock sets and a storage chamber for keeping small things.  
         [0003]     2. Description of the Related Art  
         [0004]     Conventional locks mainly include two types, namely, the combination lock operatable by a set of numbered wheels and the pin tumbler lock operatable by a key. A regular combination lock comprises a casing, a shackle, and a set of numbered wheels mounted in the casing. The casing has a plurality of through holes for accommodating the numbered wheels. The user can rotate the numbered wheels to show the correct number combination, thereby unlocking the shackle. There is also known a combination lock that provides a set of pushbutton digits for pressing by the user to input the correct number combination to unlock the lock.  
         [0005]     Conventional combination locks commonly use three or four numbered wheels to compose number combinations. This design provides only a limited number of number combinations, and a thief can solve the riddle to get the correct number combination within a short time. Further, after a long use of a combination lock that provides a set of pushbutton digits, the pushbuttons may become loosened. In this case, a thief can easily solve the riddle to get the correct number combination of the combination lock easily. Therefore, the aforesaid conventional combination locks have low security.  
       SUMMARY OF THE INVENTION  
       [0006]     The present invention has been accomplished under the circumstances in view. It is therefore one objective of the present invention to provide a padlock, which uses two combination lock sets to complicate the riddle of the number combinations, increasing the security level.  
         [0007]     It is another objective of the present invention to provide a padlock, which has a storage chamber for keeping keys, memo, or other small items.  
         [0008]     To achieve these objectives of the present invention, the padlock comprises a base shell, a cover shell, a shackle assembly, and two combination lock sets. The cover shell is pivoted to and openably covered on the base shell to define with the base shell a storage chamber therebetween. The cover shell has a plurality of through holes in communication with the storage chamber. The shackle assembly has a shackle movably mounted in the base shell. The combination lock sets are mounted to the cover shell inside the storage chamber. Each of the combination lock sets has a latch engagable with the base shell for locking the cover shell to the base shell, a plurality of numbered wheels respectively peripherally extending out of the through holes of the cover shell, and a movable plate actuactable by the numbered wheels to move relative to the latch for engaging or disengaging the latch to further have the latch engage or disengage with the base shell so as to lock or unlock the cover shell the said base shell. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0009]      FIG. 1  is a perspective view of a padlock according to a preferred embodiment of the present invention.  
         [0010]      FIG. 2  is an exploded view of the padlock according to the preferred embodiment of the present invention.  
         [0011]      FIG. 3  is a sectional view of the preferred embodiment of the present invention, showing the movable plates stopped against the respective latches.  
         [0012]      FIG. 4  is a schematic sectional view of the preferred embodiment of the present invention, showing that the cover shell is opened from the base shell and the movable plates are disengaged from the respective latches.  
         [0013]      FIG. 5  is a schematic drawing showing the action of the control plate relative to the neck of the straight endpiece of the shackle according to the preferred embodiment of the present invention.  
         [0014]      FIG. 6  is a front view of a second preferred embodiment of the padlock according to the present invention; wherein the cover shell is removed for better understanding. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0015]     As shown in  FIGS. 1 and 2 , a padlock  10  in accordance with the preferred embodiment of the present invention comprises a base shell  20 , a locating bar  23 , a cover shell  30 , a shackle assembly  40 , and two combination lock sets  50 .  
         [0016]     The base shell  20  is a rectangular shell, having a first shackle groove  202  and a second shackle groove  204  bilaterally disposed at the top and arranged in parallel, and two posts  21  bilaterally perpendicularly extending from the front side and having respectively an inner notch  212  near the free end. The shackle grooves  202  and  204  have a semicircular cross section. The locating bar  23  is affixed to the base shell  20  with fastening members, for example, tie screws  25 . The locating bar  23  has a first shackle groove  232  and a second shackle groove  234  that match the first shackle groove  202  and second shackle groove  204  of the base shell  20  respectively. The first shackle groove  232  and the second shackle groove  234  have a semicircular cross section. After installation of the locating bar  23  in the base shell  20 , the first shackle grooves  202  and  232  form a round through hole for receiving a part of the shackle assembly  40 , and the second shackle grooves  204  and  234  form another round through hole for receiving another part of the shackle assembly  40 .  
         [0017]     The cover shell  30  has the bottom side thereof pivotally connected to the bottom side of the base shell  20 . Therefore, the cover shell  30  can be closed on the base shell  20  or opened from the base shell  20 . When the cover shell  30  is closed on the base shell  20 , the peripheral wall of the cover shell  30  is closely abutted against the peripheral wall of the base shell  20 , thereby defining a storage chamber  31  in between the base shell  20  and the cover shell  30 . The cover shell  30  has a plurality of first rectangular through holes  32  and a plurality of second rectangular through holes  33  symmetrically arranged at two different elevations in communication with the storage chamber  31 , two compartments  34  respectively disposed corresponding to the first rectangular through holes  32  and the second rectangular through holes  33 , and two transverse grooves  35  bilaterally set between the compartments  34  and aligned in a line.  
         [0018]     The shackle assembly  40  comprises a substantially U-shaped shackle  42  and a control member  44 . The shackle  42  comprises a substantially U-shaped shackle body  421 , and a straight endpiece  423  axially extending from one end of the shackle body  421 . The straight endpiece  423  is pivotally and axially movably mounted in the round hole of the first shackle grooves  202  and  232 , for enabling the other end of the shackle body  421  to be inserted into the round hole of the second shackle grooves  204  and  234 . Further, the straight endpiece  423  of the shackle  42  has a neck  425  disposed inside the round hole of the first shackle grooves  202  and  232 . The control member  44  is pivotally mounted inside the base shell  20  and provided with an actuating portion  441  and a retaining portion  443  at two sides of the pivoted middle part thereof to the base shell  20 . The retaining portion  443  is attached to the neck  425  of the endpiece  423  of the shackle  42  to stop the shackle  42  from axial movement relative to the base shell  20 . When pressed the actuating portion  441 , the control member  44  is biased to disengage the retaining portion  443  from the neck  425  of the endpiece  423 , and therefore the shackle  42  is unlocked. The shackle assembly  40  further comprises a spring member  46  stopped between the actuating portion  441  and the base shell  20 . The spring member  46  imparts an outward force to the actuating portion  441 , thereby holding the retaining portion  443  in engagement with the neck  425  of the endpiece  423  of the shackle  42 .  
         [0019]     Referring to  FIG. 3  and  FIGS. 1 and 2  again, the two combination lock sets  50  are located inside the chamber  31 . The combination lock sets each have a set of numbered wheels  55  and a movable plate  56 . A holder frame  51  is affixed to the cover shell  30  with fastening members, for example, tie screws  52  to hold the two combination lock sets  50  in the compartments  34  respectively and to have the numbered wheels  55  be respectively peripherally extended out of the first and second rectangular through holes  32  and  33  of the cover shell  30 . The two combination lock sets  50  further comprise two latches  53  respectively slidably mounted in the transverse grooves  35  of the cover shell  30 , and a spring member  54 . Each of the latches  53  has a front end terminating in a tongue  532  corresponding to the inner notches  212  of the posts  21 . The spring member  54  is stopped between the rear ends of the latches  53  and adapted to force the tongues  532  of the latches  53  into engagement with the inner notches  212  of the posts  21 . The two movable plates  56  are respectively coupled to the two numbered wheel sets  55  for stopping against the rear ends of the latches  53  to prohibit displacement of the latches  53  in the grooves  35 . When the cover shell  30  is in the opened status, the movable plates  56  are disengaged from the latches  53  for allowing movement of the latches  53  in the respective grooves  35  away from the inner notches  212  of the posts  21 .  
         [0020]     When the user would like to open the padlock  10 , he/she needs to rotate the numbered wheels of the two numbered wheel sets  55  to show the correct combination for each numbered wheel set  55 . At this time, the movable plates  56  are biased relative to the two latches  53  and respectively disengaged from the latches  53  as shown in  FIG. 4 . At this time, the user can pull the cover shell  30  outwards from the base shell  20  to open the storage chamber  31 , and then press the actuating portion  441  of the control member  44  to disengage the retaining portion  443  from the neck  425  of the straight endpiece  423  of the shackle  42 , as shown in  FIG. 5 , thereby unlocking the shackle  42 . Thus, the user can use the padlock  10  to lock things, and can keep a memo or any of a variety of small items in the storage chamber  31 . Thereafter, the user can close the cover shell  30  on the base shell  20 , and then rotate the numbered wheels of each numbered wheel set  55  to show a wrong number combination respectively. At this time, the movable plates  56  are biased and stopped against the rear ends of the latches  53 , so that the tongues  532  of the latches  53  will be positively engaged with the inner notches  212  of the posts  21 ; therefore, the cover shell  30  is locked to the base shell  20 .  
         [0021]     As indicated above, the padlock  10  uses two numbered wheel sets  55  to control the latches  53  in locking/unlocking the cover shell  30 . The use of the two numbered wheel sets  55  greatly complicates the riddle of the number combinations, increasing the security level. Further, the storage chamber  31  of the padlock  10  can be used to keep keys, memos, or other small items.  
         [0022]      FIG. 6  shows an alternate preferred embodiment of the present invention. According to this embodiment, the padlock  60  is substantially similar to the aforesaid first embodiment with the exception that the shackle  61  has two straight endpieces  612  and  614  and a notch  616  at each of the straight endpieces  612  and  614 . When the two numbered wheel sets  63  respectively show the correct number combination, the two movable plates  632  are moved away from the respective latches  62 , allowing disengagement of the latches  62  from the notches  616  of the straight endpieces  612  and  614 , thereby unlocking the shackle  61 . The padlock  60  of this second embodiment achieves the same effects as the aforesaid first embodiment.  
         [0023]     Although particular embodiments of the 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 invention. Accordingly, the invention is not to be limited except as by the appended claims.

Technology Category: 4