Patent Publication Number: US-7210318-B2

Title: Padlock

Description:
CROSS-REFERENCE 
   This is a continuation-in-part application of the co-pending U.S. Ser. No. 10/671,659, filed on Sep. 29, 2003. 

   TECHNICAL FIELD 
   This invention relates generally to a padlock, in particular, to a padlock which has a block member and a dual locking device. 
   BACKGROUND OF THE INVENTION 
   A conventional padlock generally includes a lock body, a locking device and a shackle so as to lock an object, as disclosed in U.S. Pat. Nos. 4,751,830 and 6,539,761. Another conventional padlock not only includes a lock body, a dual locking device and a shackle, but also includes a block member to retain or to release the shackle, also as disclosed in U.S. Pat. No. 6,848,283 and U.S. Patent Publication Nos. 2002/0088256, 2004/0226323 and 2004/0226324. The block member of the conventional padlock is mainly arranged for the dual locking device, especially for a key locking device as so to controlling movements of the shackle. However, connections between the block member and the dual locking device are arranged to be complicated. Therefore, an improved padlock is in great demand. 
   SUMMARY OF INVENTION 
   It is therefore an object of the present invention to provide a padlock, which has a block member and a dual locking device. 
   More specifically, the padlock of the present invention comprises a lock body, a shackle, a block member, an elastic member, a combination locking device and a key locking device. The shackle is movable relative to the lock body between a locked position and an unlocked position, and the shackle has a first end movably installed in the lock body and a second end. The block member is movably connected to the lock body and comprises a button provided for retaining the second end of the shackle in the locked position, a supporter protruding from the button, and a base protruding from the supporter. The elastic member is installed around the button and has one end against the lock body and the other end against the supporter. The combination locking device is installed within the lock body for controlling movements of the shackle. The first end of the shackle is movable to the unlocked position when the combination locking device is unlocked. The key locking device is installed within the lock body and connected to the base of the block member for controlling movements of the shackle. The block member is movable axially, when the key locking device is operated by a key. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
     The invention will be more clearly understood after referring to the following detailed description read in conjunction with the drawings wherein: 
       FIG. 1  is a perspective view of a padlock as a preferred embodiment of the present invention; 
       FIG. 2  is a cross sectional view of the padlock, showing a shackle of the padlock being in a locked position; 
       FIG. 3  is an exploded view of a block member and a control unit of the padlock; and 
       FIG. 4  is a cross sectional view of the padlock, showing the shackle being in an unlocked position by operating a key locking device. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIGS. 1–4  show a padlock as a preferred embodiment of the present invention. In  FIGS. 1 and 2 , the padlock comprises a lock body  1 , a shackle  2 , a block member  3 , an elastic member  4 , a combination locking device  5  and a key locking device  6 . The shackle  2  is movable relative to the lock body  1  between a locked position and an unlocked position, and the shackle  2  has a first end  20  movably installed in the lock body  1  and a second end  21 . The block member  3  is movably connected to the lock body  1  and comprises a button  30  provided for retaining the second end  21  of the shackle  2  in the locked position, a supporter  31  protruding from the button  30 , and a base  32  protruding from the supporter  31 . Additionally, the supporter  31  and the base  32  are installed within the lock body  1 . The button  30  is movable to expose to the lock body  1  or to conceal from the lock body  1 . Furthermore, the button  30  of the block member  3  has a recess  300  for receiving the second end  21  of the shackle  2 , and the recess  300  is formed on a top surface of the button  30 . 
   As shown in  FIG. 2 , the elastic member  4  is installed around the button  30  and has one end against the lock body  1  and the other end against the supporter  31 . Preferably, the elastic member  4  is a compression spring in the present invention. The combination locking device  5  is installed within the lock body  1  for controlling movements of the shackle  2 . The first end  20  of the shackle  2  is movable axially and rotatable to the unlocked position when the combination locking device  5  is unlocked. The key locking device  6  is installed within the lock body  1  and connected to the base  32  of the block member  3  for controlling movements of the shackle  2 . The block member  3  is movable axially, when the key locking device  6  is operated by a key  7 , which is a unique key and possessed by an authorized official only. 
   In  FIGS. 2 and 3 , the base  32  of the block member  3  has an inclined surface  320 , which has a hole  321  therein, and the key locking device  6  comprises a body  60 , a rotor  61  and a control unit  62 . The body is fixed in the lock body  1 . The rotor  61  is installed in the body  60  and has a first end for receiving the key  7  and a second end extending from the body  60 . The control unit  62  is rotatably connected to the second end of the rotor  61  and has a slope surface  620  engageable with the inclined surface  320  of the base  32 . Furthermore, the slope surface  620  has a cylinder  621  formed thereon so as to engage with the hole  321 , and has a mounting portion  622  for mounting on the second end of the rotor  61 . 
     FIG. 2  shows the padlock being locked, and the block member  3  being exposed to the lock body  1  to retain the second end  21  of the shackle  2  in the locked position where an edge of the inclined surface  320  of the base  32  contacts with an edge of the slope surface  620  of the control unit  62 . Additionally, both the combination locking device  5  and the key locking device  6  are not operated. 
     FIG. 4  shows the padlock being unlocked by operating the key locking device  6  via the key  7 , and the block member  3  being concealed from the lock body  1  to allow the second end  21  of the shackle  2  moving to the unlocked position where the inclined surface  320  of the base  32  is engaged with the slope surface  620  of the control unit  62  by operating the key  7  to drive the rotor  61  to rotate the slope surface  620  via the mounting portion  622 . When the slope surface  620  is rotated, the inclined surface  320  is moved downwardly so as to engage with the slope surface  620 . Accordingly, the button  30  of the block member  3  is concealed from the lock body  1 , and can move steadily and synchronously via the elastic member  4 . 
   Additionally, when the padlock being unlocked by operating the combination locking device  5  via dialing a set of unlocking codes, the first end  20  of the shackle  2  can be axially and rotatably moved to the unlocked position, and the second end  21  of the shackle  2  can accordingly move away from the button  30  of the block member  3 . 
   Numerous characteristics and advantages of the invention have been set forth in the foregoing description, together with details of the structure and function of the invention, and the novel features thereof are pointed out in appended claims. The disclosure, however, is illustrative only, and changes may be made in detail, especially, in matters of shape, size and arrangement of parts, materials and the combination thereof within the principle of the invention, to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.