Abstract:
A buckle includes a first fastener and a second fastener. The second fastener has two hooks. The first fastener includes a socket, a locking piece disposed in the socket, and two first locking portions formed on the socket for mating with the hooks. The locking piece is slidingly connected in the socket to cooperate with the second fastener. When the first fastener is engaged with the second fastener, the locking piece enters the second fastener to restrict the movement of the second fastener, so that the second fastener cannot be released unless the locking piece is removed from the second fastener and the hooks of the second fastener are pressed. Thus, the second fastener can be released only when the locking piece is moved, thereby preventing a problem that the second fastener may be separated from the first fastener when the hooks of the second fastener are incautiously pressed. A user has to move the locking piece with one hand and presses the hooks with another hand. Thus, such an action performed by two hands is uneasy for a child, thereby generating a safety effect.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an article for daily use, and in particular to a buckle. 
     2. Description of Prior Art 
     In general, when two ends of a belt of a camera, baggage or other device are needed to be connected to or disconnected from each other quickly, two fasteners mating with each other are often used. The two fasteners are referred to as a first fastener and a second fastener respectively hereinafter. The second fastener can be inserted into the first fastener and engaged therewith. The combination of the first fastener and the second fastener is called a buckle. When the first fastener is connected with the second fastener, the second fastener is pressed by the first fastener, so that the second fastener can be inserted into the first fastener deeply. Then, hooks on both sides of the second fastener will be locked by locking portions on both sides of the first fastener respectively by means of the plastic deformation of the hooks. When a user intends to separate the first fastener from the second fastener, the user can press a portion of hooks protruding from the locking portions inwardly, so that the hooks of the second fastener can be removed from the locking portions of the first fastener. However, the user may incautiously press the portion of the hook of the second fastener protruding from the locking portions of the first fastener, so that the second fastener may be removed from the first fastener undesirably. Especially when the buckle is used in a vertical orientation, the second fastener may slide out of the first fastener due to its gravity force. Even, the second fastener may be separated from the first fastener when the buckle is swung by a child. As a result, the articles received in a baggage or the camera connected to the buckle may be fallen into the ground to suffer damage. 
     SUMMARY OF THE INVENTION 
     In order to solve the above problems, an objective of the present invention is to provide a safety buckle. 
     The present invention is to provide a buckle, which includes a first fastener and a second fastener mating with the first fastener. The second fastener is provided with a hook. The first fastener includes a socket, a locking piece provided in the socket, and a first locking portion provided on the socket for engaging with the hook. The locking piece is slidingly provided in the socket for preventing the hook from removing from the first locking portion. 
     Preferably, the socket is provided with a push button connected to the locking piece for pushing the locking piece. The push button is provided with a button hook connected to the locking piece. 
     Preferably, the locking piece and the socket are in interference fit. The locking piece is connected to an elastic piece. One end of the elastic piece is mounted on the locking piece, while the other end thereof abuts the socket. 
     Preferably, the locking piece includes a pushing portion connected to the push button and two stoppers connected to both sides of the pushing portion. The stopper is located to cooperate with the second fastener. One end surface of the stopper is provided with an accommodating trough for receiving an elastic piece. The elastic piece is received in the accommodating trough and a portion of the elastic piece protrudes from the accommodating trough to abut the socket. The socket is provided therein with a guiding groove. The locking piece is mounted in the guiding groove and slides along the guiding groove. 
     Preferably, upper and lower surfaces of the pushing portion protrude from the stopper. The stopper includes a stopping body and a stopping boss protruding from the stopping body. The stopping boss is provided adjacent to the pushing portion. The stopping boss is provided on each side of the pushing portion and is located at a level higher that of one end surface of the pushing portion. The stopping boss and the pushing portion form a restricting trough. The pushing portion is provided with a button locking trough for mating with the push button. 
     Preferably, the stopper is provided with a stopping strip. A mounting groove is formed between the stopping strip and the pushing portion. One end surface of the stopping body and the stopping boss together cooperate with the second fastener. One end surface of the stopping body cooperating with the second fastener is provided into a slope. 
     Preferably, the socket is of a hollow structure with an open end. The socket includes an upper wall, a lower wall, a left side wall, a right side wall, and a rear wall. The guiding grooves are formed in pairs by a guiding strip protruding from the inner surface of each of the upper wall and the lower wall. The guiding strip is received in the mounting groove. The mounting groove moves along the guiding strip. The first locking portion is an opening formed on a waist portion of the first fastener, and the opening extends from the left side wall or the right side wall to the upper wall or the lower wall. The first locking portion is provided with an engaging wall for mating with the hook. The upper wall or the lower wall is provided with a button trough for receiving the push button. The button hook passes through the button trough to enter the button locking trough to be fixed therein. The push button moves along the button trough. 
     Preferably, the second fastener includes a connecting wall. Two hooks are symmetrically provided on the connecting wall. A post is provided between the two hooks on the connecting wall. The post slidingly cooperates with the guiding groove. The hook is provided with a barb for mating with the engaging wall. 
     Preferably, an end surface of the post is located to mate with the pushing portion. The engaging wall is a curved slope for mating with the barb. The post is provided with a reinforcement rib. A distal end of the socket is provided with a first connecting piece. A distal end of the second fastener is provided with a second connecting piece. 
     Preferably, a first elongate hole is formed between the first connecting piece and the rear wall. A second elongate hole is formed between the second connecting piece and the connecting wall. A pair of guiding grooves is provided on the inner surfaces of the upper wall and the lower wall. The stopping strips are provided on both sides of the pushing portion. A mounting groove is formed between the stopping strip and the pushing portion. The stopping strips are provided on the upper and lower surfaces of the stopper to correspond to the guiding grooves. Two push buttons are provided on the socket. Two elastic pieces are symmetrically provided in the socket. Two accommodating troughs are symmetrically provided in the locking piece for corresponding to the elastic pieces. 
     The first fastener has the locking piece moving in the socket to prevent the hooks of the second fastener from removing the first locking portions of the first fastener. When the first fastener is engaged with the second fastener, the locking piece is inserted into the second fastener to restrict the movement of the second fastener, so that the second fastener cannot be released unless the locking piece is removed from the second fastener and the hooks of the second fastener are pressed. Thus, the second fastener can be released only when the locking piece is moved, thereby preventing a problem that the second fastener may be separated from the first fastener when the hooks of the second fastener are incautiously pressed. A user has to move the locking piece with one hand and presses the hooks with another hand. Thus, such an action performed by two hands is uneasy for a child, thereby generating a safety effect. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view showing an embodiment of the present invention; 
         FIG. 2  is another exploded view showing the embodiment of the present invention; 
         FIG. 3  is a schematic view showing the connection of a first fastener and a second fastener of the embodiment of the present invention; 
         FIG. 4  is a cross-sectional view showing the embodiment of the present invention; 
         FIG. 5  is a schematic view showing the disconnection of the first fastener from a second fastener of the embodiment of the present invention; 
         FIG. 6  is a schematic view showing a procedure of the insertion of the second fastener into the first fastener according to the embodiment of the present invention; 
         FIG. 7  is another schematic view showing the procedure of  FIG. 6 ; and 
         FIG. 8  is another schematic view showing the procedure of  FIG. 7 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention will be described in more detail with reference to a preferred embodiment thereof shown in the accompanying drawings 
     As shown in  FIGS. 1 to 5 . The buckle of the present invention includes a first fastener  1  and a second fastener  2  mating with the first fastener  1 . The second fastener  2  includes a connecting wall  20 , two hooks  22  formed on the connecting wall  20 , a post  24  and a connecting piece  26  formed on the connecting wall  20 . 
     The hooks  22  and the second connecting piece  26  are provided on both sides of the connecting wall  20 , respectively. The second connecting piece  26  is formed on a distal end of each hook  22 . A second elongate hole  28  is formed between the second connecting piece  26  and the connecting wall  20 . The second connecting piece  26  is configured to connect to a belt. The belt passes through the second elongate hole  28  to be connected to the second connecting piece  26 . 
     The hooks  22  are symmetrically formed on both ends of the connecting wall  20 . Each of the hooks  33  includes a connecting portion  220  connected to the connecting wall  20 , and a second locking portion  222  connected to the connecting portion  220 . 
     The second locking portion  222  includes an open surface  2220  located inside, a second locking surface  2222 , and a barb  2224  located outside to be engaged with the first fastener  1 . The barb  2224  has a slope. 
     The post  24  is formed between the two hooks  22 . Both sides of the post  24  are formed with a reinforcement rib  240  respectively. The hooks  22  and the post  24  formed between the two hooks  22  are connected to the connecting wall  20  to form a shape like a Chinese character “           ”.
     The first fastener  1  includes a socket  10 , a locking piece  12  provided in the socket  10 , and a push button  14  disposed on the socket  10  to be connected to the locking piece  12 . The locking piece  12  is disposed in the socket  10  to move therein. 
     The socket  10  is of a hollow structure with an open end. The socket  10  is constituted of an upper wall  100 , a lower wall  101 , a left side wall  102 , a right side wall  103 , and a rear wall  104 . The distal end of the socket  10  has a first connecting piece  109 . A first elongate hole  108  is formed between the first connecting piece  109  and the rear wall  104 . 
     The socket  10  has two guiding grooves  105  for mating with the post  24  of the second fastener  2 . The two guiding grooves  105  are formed by two guiding strips  1050  protruding from the inner surfaces of the upper wall  100  and the lower wall  101  respectively. In the present invention, in order to guarantee the smooth movement of the second fastener  2  in the socket  10 , the inner surfaces of the upper wall  100  and the lower wall  101  are provided with a pair of guiding strips  1050  respectively, thereby forming the pair of guiding grooves  105 . The socket  10  is provided on the upper wall  100  or the lower wall  101  with a button trough  106  for receiving the push button  14 . The push button  14  is movably mounted in the button trough  106 . 
     The socket  10  is further formed with a first locking portion  107  for mating with the hooks  22  of the second fastener  2 . The first locking portion is an opening formed on the waist portion of the first fastener  1 . The first locking portions  107  are formed on the openings of the left side wall  102  and the right side wall  103  respectively, and the openings extend from the left side wall  102  and the right side wall  103  towards the upper wall  100  and the lower wall  101  respectively. The first locking portion  107  is provided with an engaging wall  1070  for engaging with the hook  22 . The engaging wall  1070  is also formed with a slope for mating with the barb  2224  of the hook  22 . 
     In the present embodiment, the upper wall  100  and the lower wall  101  of the socket  10  are mounted with a push button  14  respectively. The push button  14  includes a button body  140  and button hooks  142  connected to the button body  140 . The button hooks  142  are inserted into the locking piece  12  and fixedly connected thereto. The button hooks  142  are connected to the locking piece  12  so as to drive the locking piece  12  to move together. In order to help the user to push the push button  14  easily, the upper surface of the button body  140  is formed with a convex surface  1400 . When the user intends to press the push button  14 , the user can press the convex surface  1400  of the button body  140  with his/her finger. 
     The locking piece  12  includes a pushing portion  120  connected to the push button  14  and two stoppers  122  connected to both sides of the pushing portion  120 . The locking piece  12  is connected to elastic pieces, which are, for example, springs  18  in the present embodiment. 
     The upper and lower surfaces of the pushing portion  120  protrude from the stopper  122 . The pushing portion  120  is formed with a button locking trough  1200  for engaging with the button hooks  142 . Two button locking troughs  1200  are provided to correspond to the two push buttons  120  respectively on the upper and lower surfaces of the pushing portion  120 . The button hooks  142  are received in the button locking trough  1200  and fixed therein. One end surface of the pushing portion  120  facing the second fastener  2  is located at a level lower than that of the stopper  122 . 
     The stoppers  122  are symmetrically provided on both sides of the pushing portion  120 . The upper surface or the lower surface of the stopper  122  is formed with a stopping strip  125 . A mounting groove  127  is formed between the stopping strip  125  and the pushing portion  120 . The upper surface or the lower surface of the stopper  122  and both sides of the pushing portion  120  is provided with a stopping strip  125 . When the locking piece  12  is to be mounted, the mounting grooves  127  are aligned with the guiding strips  1050  of the socket  10 , so that the guiding strips  1050  can be received in the mounting grooves  127 . The locking piece  12  and the socket  10  are in interference fit. The outer surface of the locking piece  12  is profiled to correspond to the inner surface socket  10 , so that the locking piece  12  can slide along the guiding strips  1050 . 
     The stopper  122  includes a stopping body  124  and a stopping boss  126  protruding from the stopping body  124 . One end surface of the stopping body  124  mating with the second fastener  2  is formed into a slope. 
     One end of the stopper  122  is further formed with an accommodating trough  1222  for receiving the spring  18 . Two accommodating troughs  1222  are symmetrically formed on both sides of the pushing portion  120 . Each of the accommodating troughs  1222  is configured to receive a spring  18  therein. Of course, more than one spring  18  can be received in the accommodating trough  1222 . Thus, one end of the spring  18  is received in the accommodating trough  1222 , and the other end thereof abuts the inner surface of the rear wall  104  of the socket  10 , thereby providing a restoring force for the locking piece  12 . The length of the spring  18  is larger than that of the accommodating trough  1222 , so that a portion of the spring  18  can protrude from the accommodating trough  1222  to abut the inner surface of the rear wall of the socket  10 . 
     The stopping boss  126  is provided adjacent to the pushing portion  120 . The stopping bosses  126  are provided on both sides of the pushing portion  120  and are located at a level higher than that of the end surface of the pushing portion  120 . A restricting trough  128  is formed between the stopping bosses  126  and the pushing portion  120 . 
     As shown in  FIGS. 6 to 8 , the post  24  of the second fastener  2  is received in the guiding grooves  105  of the socket  10  and is slidingly mated with the guiding grooves  105 . When the first fastener  1  is engaged with the second fastener  2 , the post  24  is inserted into the restricting trough  128  of the locking piece  12 . 
     The hooks  22  of the second fastener  2  are engaged with the first locking portions  107  on both sides of the socket  10 . The barb  2224  of the hook  2  is engaged with the engaging wall  1070 . The engagement between the barb  2224  and the engaging wall  1070  is so strong that they cannot be detached from each other easily. 
     In a normal state, the distance between the open surfaces  2220  of the two hooks  22  is larger than the distance of the two stopping boss  126 . The first fastener  1  is engaged with the second fastener  2 . The stopping bosses  126  of the locking piece  12  are inserted into a space between the open surfaces  2220  of the hook  22  and the post  24 . 
     The second fastener  2  is made of plastic materials. The distance between the two hooks  22  of the second fastener  2  is larger than the distance between the inner walls of the left side wall  102  and the right side wall  103  of the socket  10 . When the second fastener  2  is inserted into the first fastener  1 , the two hooks  22  of the second fastener  2  are pressed inwardly by the inner walls of the left side wall  102  and the right side wall  103  to generate an elastic deformation. As a result, the distance between the open surfaces  2220  of the two hooks  22  is compressed to be smaller than the distance between the two stopping bosses  126 . 
     The post  24  enters the guiding grooves  105  and moves along the guiding grooves  105  until the second locking surfaces  2222  of the two hooks  22  of the second fastener  2  abut the end surfaces of the stopping bosses  126  respectively. At this time, the second fastener  2  pushes the locking piece  12  to move along the guiding grooves  105 . The locking piece  12  moves to press the spring  18  and moves further into the socket  10  until the barbs  2224  of the two hooks  22  exceed the engaging walls  1070  of the left side wall  102  and the right side wall  103  of the socket  10 . At this time, the two second locking portions  222  of the hooks  22  of the second fastener  2  will return to their original shape due to their elasticity if there is no external force. The hooks  22  on both sides of the second fastener  2  are engaged with the first locking portions  107  of the first fastener  1 . The barb  2224  is engaged with the engaging wall  1070 . Because of the reaction between the slope of the barb  2224  and the slope of the engaging wall  1070 , the engagement between the first fastener  1  and the second fastener  2  becomes so strong that they cannot be detached from each other easily. Further, since the distance between the open surfaces  2220  of the two hooks  22  returns to its normal length, the distance between the open surfaces  2220  will be larger than the distance between the two stopping bosses  126 . The second locking surface  2222  of the hook  22  no more abuts the end surface of the corresponding stopping boss  126 , so that the external force for pressing the spring  18  is released. As a result, the spring  18  provides a restoring force to the locking piece  12 , thereby making the locking piece  12  to return its original position. The locking piece  12  moves along the guiding grooves  105  to return its original position. The stopping bosses  126  of the locking piece  12  are inserted into the space between the open surfaces  2220  of the hook  22  and the post  24 . 
     At this time, if the user presses the barb  2224  of the hook  22  of the second fastener  2  exposed to the opening of the first locking portion  107 , the barb  2224  is blocked by the stopping boss  126  between the open surfaces  2220  and the post  24 , so that the barb  2224  cannot be pressed inwardly any more. Further, the barb  2224  cannot be separated from the engaging wall  1070 , thereby generating a safety effect. 
     When the user intends to separate the first fastener  1  from the second fastener  2 , the user pushes the push button  14  toward the rear wall  104  of the socket  10 . The push button  14  moves along the button trough  106  to drive the locking piece  12  to move close to the rear wall  104  of the socket  10 . At the same time, the locking piece  12  presses the spring  18  until the stopping boss  126  of the locking piece  12  is removed from the space between the open surfaces  2220  of the hook  22  and the post  24 . As a result, the first fastener  1  can be separated from the second fastener  2 . 
     When the user presses again the barbs  2224  of the hook  22  of the second fastener  2  exposed to the opening of the first locking portion  107 , the engagement between the slope of the barb  2224  and the slope of the engaging wall  1070  can be released. As a result, the user can pull the second fastener  2  in a direction away from the first fastener  1 , whereby the second fastener  2  can be separated from the first fastener  1 . At this time, the locking piece  12  returns to its original position by means of the restoring force of the spring  18 . 
     Although the present invention has been described with reference to the foregoing preferred embodiment, it will be understood that the invention is not limited to the details thereof. Various equivalent variations and modifications can still occur to those skilled in this art in view of the teachings of the present invention. Thus, all such variations and equivalent modifications are also embraced within the scope of the invention as defined in the appended claims.