Abstract:
A buckle for belts comprises a first shell unit having a releasing piece, a second shell unit connected under the first shell unit, a locking element pivotally connected to a seat of the second shell element, and a moving element movably installed behind the locking element. When a strap-connecting element is inserted into the buckle from a front end thereof, the locking element is pushed and is pivotally rotated by the strap-connecting element to make the locking element lock the strap-connecting element. Simultaneously, the moving element is moved to support the locking element so that the state of the locking element firmly securing the strap-connecting element is maintained. When the releasing piece of the first shell unit is actuated, the moving element is cooperated by the releasing element and no longer supports the locking element to release the state of the engagement between the locking element and the strap-connecting element.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates generally to a buckle for belts, and more particularly to a buckle for belts having a locking element which is supported by a moving element to firmly lock a strap-connecting element.  
       BACKGROUND OF THE INVENTION  
       [0002]     The conventional buckle for the safety belt, such as shown in U.S. Pat. No. 5,165,150, is further required the functions of simple structure, low cost, easy operation, and firm engagement, in addition to the basic functions of connecting and securing the safety belt. However the designs of the conventional buckle about all above aspects are not perfect and still remain some space to be filled up.  
       SUMMARY OF THE INVENTION  
       [0003]     Accordingly, the present invention relates to a buckle for belts that can substantially obviate one or more of the problems due to the limitations and disadvantages of the related arts.  
         [0004]     One object of the present invention is the provision of a buckle for belts whose structure is simple.  
         [0005]     Another object of the present invention is the provision of a buckle for belts whose cost is low.  
         [0006]     A further object of the present invention is the provision of a buckle for belts which is easily operated.  
         [0007]     A yet object of the present invention is the provision of a buckle for belts which can firmly lock the straps.  
         [0008]     Additional features and advantages of the invention will be set forth in the description which follows, and in portion will be apparent from the description, or may be learned by practice of the invention. The objectives and advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.  
         [0009]     To achieve these and other advantages and according to the purpose of the present invention, as embodied and broadly described, a buckle for belts for connecting a strap-connecting element, the buckle comprising: a first shell unit having a releasing piece; a second shell unit connected to the first shell unit and defining an entrance together with the first shell unit, the second shell unit having a slit far away from the entrance and a seat situated between the entrance and the slit; a locking element pivotally connected to the seat of the second shell unit and having a latch near the entrance, a ledge near the slit, and a shoulder formed between the latch and the ledge; and a moving element movably installed near the ledge; whereby when the strap-connecting element is inserted into the entrance between the first shell unit and the second shell unit, the shoulder is pushed by the strap-connecting element so that the locking element is pivotally rotated to make the latch lock the strap-connecting element and the moving element is moved to contact with the ledge so as to keep the locking element in a state of firmly securing the strap-connecting element; when the releasing piece of the first shell unit is actuated, the releasing piece cooperates with the moving element to escape the moving element from the ledge and release the latch from the state of locking the strap-connecting element.  
         [0010]     It is preferred that the buckle has an elastic element between the moving element and the second shell unit to cooperate the moving element to abut against the ledge.  
         [0011]     It is preferred that the releasing piece has at least a guiding tab for cooperating the moving element to escape from the ledge.  
         [0012]     It is preferred that the first shell unit further has a cap and a perforation in the cap, and the releasing piece is accommodated in the perforation.  
         [0013]     It is preferred that the releasing piece has a protrusion at an end of the at least the guiding tab for securing the releasing piece and the cap together.  
         [0014]     It is preferred that the first shell unit has an elastic element between the cap and the releasing piece for reposition of the releasing piece.  
         [0015]     It is preferred that the seat further comprises two parallel plates, and the buckle further has a pin for pivotally connecting the locking element to the two plates.  
         [0016]     It is preferred that the buckle further has an elastic element at the seat for reposition of the locking element.  
         [0017]     It is preferred that the buckle further has a pushing element near the entrance to push the strap-connecting element out of the buckle.  
         [0018]     It is preferred that the second shell unit further has a base and a main body, and the base has a plurality of costas to secure the main body.  
         [0019]     It is preferred that the seat and the slit are at the main body.  
         [0020]     It is preferred that the moving element has at least a guider for the seat to guide the movement of the moving element.  
         [0021]     It is preferred that the moving element has a spacer for abutting the ledge of the locking element to make the locking element firmly lock the strap-connecting element.  
         [0022]     It is preferred that the second shell unit has at least a stud for abutting one end of the elastic element.  
         [0023]     It is preferred that the moving element has at least a tunnel for receiving another end of the elastic element.  
         [0024]     It is preferred that the second shell unit comprises a base and a main body, and the main body further has at least an orifice for the passing of the at least the stud to secure the base and the main body together.  
         [0025]     It is preferred that the second shell unit has at least a stake for connecting the pushing element. It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0026]     The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a portion of the specification, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention. In the drawings:  
         [0027]      FIG. 1  is a top plane view illustrating that a strap-connecting element is engaged with the buckle according to the present invention;  
         [0028]      FIG. 2  is an assembled bottom plane view illustrating a first shell unit of the buckle according to the present invention;  
         [0029]      FIG. 3  is a perspective view illustrating that the buckle is separated from the strap-connecting element but not illustrating the first shell unit of the buckle and a cover of the strap-connecting element;  
         [0030]      FIG. 4  is a sectional view of the buckle taken along line IV-IV in  FIG. 1  and only the first shell unit instead of the second shell unit is cut to illustrate a state of the buckle according to the present invention being engaged with the strap-connecting element; and  
         [0031]      FIG. 5  is similar to  FIG. 4  except illustrating a state of the buckle according to the present invention being disengaged with the strap-connecting element 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0032]     As shown in  FIGS. 1, 2  and  3 , a buckle  9  for straps according to a preferred embodiment of the present invention comprises an upper first shell unit  1  and a lower second shell unit  2  as well as a locking element  3 , a moving element  4 , and a pushing element  5  which are interposed between the first shell unit  1  and the second shell unit  2 .  
         [0033]     The first shell unit  1  includes a cap  11 , a releasing piece  12  mounted to the cap  11 , and a first elastic member  13  interposed between the cap  11  and the releasing piece  12 .  
         [0034]     The cap  11  has a stepped first snick at the front end thereof, a perforation  112  (shown in  FIG. 5 ) at the middle portion thereof, a second snick  113  at the rear end thereof. In addition, the cap  11 , in the interior, also has two longitudinal ribs  114  parallel to each other, and a first slot  115  adjacent to the second snick  113  and between the two ribs  114 .  
         [0035]     The releasing piece  12 , at the exterior, has a ring of flange  121  and recess  122  defined by the flange  121 . In the interior, the releasing piece  12  also has a longitudinal second slot  123  at the central portion, two triangular guiding tabs  124  respectively extended from two sides of the releasing piece  12 , and two protrusions  125  respectively protruding outwardly from the distal ends of the guiding tabs  124 .  
         [0036]     The assembly of the first shell unit  1  is completed by first putting the first elastic member  13  with one end thereof into the first slot  115  of the cap  11 , then inserting the releasing piece  12  with two guiding tabs  124  into the perforation  112  and simultaneously setting another end of the first elastic member  13  into the second slot  123  of the releasing piece  12 , and finally snapping the protrusions  125  of the guiding tabs  124  with the ribs  114  of the cap  11  respectively.  
         [0037]     Because the protrusions  125  are engaged with the ribs  114  of the cap  11 , the releasing piece  12  cannot automatically separate from the cap  11 . Due to the guidance of the guiding tabs  124  and the ribs  114 , the releasing piece  12  can longitudinally slide relative to the cap  11 . However, when the releasing piece  12  is exerted only by the restoration force of the first elastic member  13  and by no other external force, the releasing piece  12  is in a normal state that the front end of the flange  121  is abutted against the front edge which defines the perforation  112 . On the contrary, when the releasing piece  12  is exerted by an external force on the recess  122  or on the flange  121 , the releasing piece  12  backwardly slides relative to the cap  11 , which results in the first elastic element  13  being further compressed. After the external force disappears, the releasing piece  12  is pushed by the restoration force of the first elastic member  13  and thus forwardly moves to the position that the flange  121  is abutted against the front edge around the perforation  112  again.  
         [0038]     The second shell unit  2  includes a base  21  made of, for example, plastic material and a main body  22  made of high strength material like metal.  
         [0039]     The base  21  has costas  211  respectively situated at the front and middle portions, two studs  212  at the rear portion, two stakes  213  at the front portion, and two grooves  214  respectively situated on the stakes  213 .  
         [0040]     The main body  22  has a slit  221  and two rectangular orifices  222  at the rear section thereof, an inlet  223  at the front section thereof, and a seat  225  constructed by two parallel plates  224  at the middle section thereof. Each plate  224  has a hole  226  at the central part and an aperture  227  at the upper-front corner.  
         [0041]     The assembly of the second shell unit  2  is accomplished by respectively inserting the two studs  212  through the two orifices  222  of the main body  22  and at the same time respectively abutting the edges of main body  22  against the costas  211  of the base  21  to secure the main body  22  to the base  21 . In another preferred embodiment, the main body  22  and the base  21  can be integrally formed as the second shell unit  2 .  
         [0042]     The hollow and curved locking element  3  has a latch  31  at the lower-front corner thereof, a ledge  32  at the rear end, a shoulder  33  near the bottom thereof between the latch  31  and the ledge  32 , two bores  34  respectively at the center of two side walls thereof, and an upwardly-opened cavity  35  between the two side walls.  
         [0043]     The locking element  3  is mounted to the second shell unit  2  as follow. First, the locking element  3  is interposed between the two plates  224  of the seat  225 . Secondly, a second elastic element  61 , such as a spring, is placed in the cavity of the locking element  3  and two ends of the second elastic element  61  are respectively inserted into the apertures  227  in the two plates  224 . Next, a pin  62  sequentially passes through the holes  226  of the plates  224 , the bores  34  of the locking element  3 , and the second elastic element  61  so as to pivotally secure the locking device  3  and the second elastic element  61  to the seat  225 .  
         [0044]     The U-shaped moving element  4  has two guiders  41  respectively at two sides, a spacer  42  connecting the two guiders  41 , and an opening  43  defined by the guiders  41  and the spacer  42 . Each guider  41  has a blind tunnel  44  which is closed at one end thereof.  
         [0045]     The moving element  4  is mounted to the second shell unit  2  as follows. First, two third elastic elements  63 , with one end thereof, are respectively inserted into the blind tunnels  44 . Then, the moving element  4  is mounted to the second shell unit  2  in the manner that the seat  225  of the main body  22  is received in the opening  43  of the moving element  4 . At this time, another ends of third elastic elements  63  are respectively abutted against the two studs  212  of the base  21 , and the spacer  42  of the moving element  4  is behind the ledge  32  of the locking element  3  as well as the inner surfaces of the two guiders  41  are abutted against the outer surfaces of the two plates  224  in the seat  225  to guide the sliding of the moving element  4  relative to the seat  225 .  
         [0046]     Two lateral ends  51  of a pushing element  5  with elasticity are respectively accommodated in the grooves  214  of the stake  213  and the front end  52  of the pushing end  52  is placed above the inlet  223  of the main body  22 .  
         [0047]     As shown in  FIG. 4  and  5 , finally, the first shell unit  1  is mounted on and fixed together with the second shell unit  2  by hot melting, snapping, screwing, or other mechanical ways so as to complete the buckle  9  for straps according to the present invention. In the meantime, the two guiding tabs  124  of the releasing piece  12  are respectively situated outside the two plates  224  of the seat  225  and in front of the moving element  4 . The first elastic member  13  is situated in the cavity  35  of the locking element  3 . The front end  52  of the pushing element  5  appears at the first snick  111  of the cap  11  and the first snick  111  is also matched together with the inlet  223  of the main body  22  to form an entrance  64  of the buckle  6 .  
         [0048]     An arc strap-connecting element  8  has a tongue  81  at the central portion thereof, a protuberance  82  on the tongue  81 , and a receptacle  83  in the tongue  81 .  
         [0049]     When the tongue  81  of the strap-connecting element  8  is inserted into the entrance  64  of the buckle  9  for straps, the tongue  81  slides along the inlet  223  of the main body  22  and further pushes against the shoulder  33  of the locking element  3 . Then, the locking element  3  is pivotally rotated counter-clockwise, as shown in  FIG. 4 , with respect to the pivotal pin  62  to the extent that the latch  31  downwardly moves into the receptacle  83  in the tongue  81  and locks the strap-connecting element  8 . In the meanwhile of the latch  31  being downwardly rotated, the ledge  32  of the locking element  3  is upwardly rotated so that the gap between the ledge  32  and the main body  22  is getting larger enough to allow the spacer  42  of the moving element  4 , which is forwardly pushed by the third elastic element  63 , to situated under the ledge  32  of the locking element  3  and the latch  31  firmly locks the tongue  81 . Besides, at this time, the protuberance  82  of the strap-connecting element  8  also abuts against the front end  52  of the pushing element  5 . Because the main body  22  can be connected with a strap (not shown) at the slit  221  and the strap-connecting element  8  can also be connected to at least a strap, the buckle  9  for straps of the present invention has the function of connecting a plurality of straps.  
         [0050]     When it is desired to separate the strap-connecting element  8  from the buckle  9  for straps, the only thing which is needed to do is to put a finger on the recess  122  or flange  121  of the releasing piece  12  and then to push the releasing piece  12  to backwardly slide relative to the cap  11 . In the meanwhile, the moving element  4  is pushed at the guiders  41  thereof by the guiding tabs  124  of the releasing piece  12  and backwardly moves until the spacer  42  of the moving element  4  escapes from the ledge  32  of the locking element  3 , that is, the spacer  42  is behind the ledge  32 . Hence, the locking element  3  can be pivotally rotated clockwise, as shown in  FIG. 5 , under the action of the restoration force of the second elastic element  61 . In other word, the ledge  32  of the locking element  3  is pivotally rotated downwardly and the latch  31  is pivotally rotated upwardly. When the latch  31  of the locking element  3  escapes from the receptacle  83  in the tongue due to upwardly rotating, the strap-connecting element  8  is sprung out of the buckle  9  for straps by means of the restoration force of the pushing element  5  exerting to the protuberance  82  of the strap-connecting element  8 .  
         [0051]     When the finger is removed from the releasing piece  12  or the releasing piece  12  is not exerted by any other external force, the releasing piece  12  is forwardly moved to the position that the flange  121  abuts against the front edge which defines the perforation  112  again by the restoration of the first elastic member  13 . At the same time, due to the restoration of the third elastic member  63 , the moving element  4  is pushed and forwardly moves. However, because the gap between the ledge  32  of the locking element  3  and the main body  22  is smaller or even there exits no gap, the spacer  42  of the moving element  4  cannot slide into the gap or under the ledge  32 . In other word, the spacer  42  is blocked by the locking element  3  and situated behind the locking element  3  in order that the latch  31  of the locking element  3  is kept in a state of being opened.  
         [0052]     This invention has been disclosed in terms of specific embodiments. It will be apparent that many modifications can be made to the disclosed structures without departing from the invention. Therefore, it is the intent of the appended claims to cover all such variations and modifications as come within the true spirit and scope of this invention.