Patent Publication Number: US-10766122-B2

Title: Pressure adjusting device of quick fixture

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The invention relates to a rapid fixture, and more particularly to a pressure adjusting device of a quick fixture. 
     2. Description of Related Art 
     In present days, various designs for decorations, furniture, and wood handicrafts are presented in the market. In the art of making wood handicrafts, a quick fixture is an important tool. 
     A conventional rapid fixture usually includes a base, on which a linkage mechanism, a handle, and a plunger are provided. The handle is connected to an input linkage of the linkage mechanism, and the plunger is connected to an output linkage of the linkage mechanism, so that the plunger is reciprocated via the linkage mechanism when a user levers thee handle to hold a workpiece (not shown). 
     In practice, various workpieces with different thicknesses are hold by the conventional rapid fixture. The plunger exerts a thick workpiece with a larger pressure than a thin workpiece. An improved quick fixture provides a pressure adjustor to adjust the pressure of the plunger exerting the workpiece. However, the pressure adjustor is complex, and it has to be operated by user. 
     BRIEF SUMMARY OF THE INVENTION 
     In view of the above, the primary objective of the present invention is to provide a pressure adjusting device of a quick fixture, which automatically adjusts a pressure on a workpiece according to a thickness of the workpiece. 
     In order to achieve the objective of the present invention, a pressure adjusting device of a quick fixture includes a main member having a first opening and a second opening at opposite ends thereof; a fixed member fixed to the main member through the second opening; a movable member movably connected to the main member through the first opening, wherein the movable member has a first stop block received in the main member, and the first stop block is larger than the first opening of the main member; and an elastic member received in the main member and having opposite end connected to the fixed member and the movable member to urge the movable member. 
     In an embodiment, the main member has a first plug connected to an end thereof, and the first plug is provided with the first opening. 
     In an embodiment, the main member has a second plug connected to an end thereof, and the second plug is provided with the second opening; the second opening is a threaded hole, and the fixed member has a threaded section to be threaded with the second opening. 
     In an embodiment, the main member has an inner threaded section on an interior side thereof, and fixed member has a first outer threaded section threaded with the inner threaded section of the main member. 
     In an embodiment, the pressure adjusting device further includes an auxiliary holder fixing the fixed member to the main member. 
     In an embodiment, the fixed member has a threaded section, and the auxiliary holder is a nut threaded onto the fixed member and abutted against the main member. 
     In an embodiment, the pressure adjusting device further includes a plunger connected to the movable member. 
     In an embodiment, the pressure adjusting device further includes a plunger connected to the fixed member. 
     In an embodiment, the movable member is provided with a first connector, and the fixed member is provided with a second connector; both the first connector and the second connector are received in the main member to be connected to the opposite ends of the elastic member. 
     In an embodiment, the elastic member is a compression spring urging the movable member to have the first stop block against the main member in a normal condition. 
     In an embodiment, the elastic member is a tension spring with opposite ends hooked to a first bore on the first connector of the movable member and a second bore on the second connector of the fixed member. 
     As a result, the present invention may make the quick fixture fix various workpieces with different thicknesses. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The present invention will be best understood by referring to the following detailed description of some illustrative embodiments in conjunction with the accompanying drawings, in which 
         FIG. 1  is a perspective view of the quick fixture of a first preferred embodiment of the present invention; 
         FIG. 2  is an exploded view of the first preferred embodiment of the present invention; 
         FIG. 3  is a sectional view of the first preferred embodiment of the present invention; 
         FIG. 4  is a sketch diagram of the first preferred embodiment of the present invention, showing a thin workpiece being held; 
         FIG. 5  is a sketch diagram of the first preferred embodiment of the present invention, showing a thick workpiece being held; 
         FIG. 6  is a perspective view of the quick fixture of a second preferred embodiment of the present invention; 
         FIG. 7  is a perspective view of the quick fixture of a third preferred embodiment of the present invention; 
         FIG. 8  is a perspective view of the quick fixture of a fourth preferred embodiment of the present invention; 
         FIG. 9  is a sectional view of the fourth preferred embodiment of the present invention, showing the elastic member in the normal condition; 
         FIG. 10  is a sectional view of the fourth preferred embodiment of the present invention, showing the elastic member being extended; and 
         FIG. 11  is a sectional view of the fifth preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows a vertical type quick fixture  2  of the first preferred embodiment of the present invention, which includes a base  50 , a linkage  52 , an output bar  54 , a plunger  56 , a handle  58 , and a pressure adjusting device  1 . The linkage  52  is pivoted on the base  50  and the handle  58 , and the output bar  54  is pivoted on the base  50  and the handle  58  to form a four-link mechanism. The pressure adjusting device  1  is movably connected to the output bar  54 , and the plunger  56  is connected to the pressure adjusting device  1 . 
     As shown in  FIG. 2  and  FIG. 3 , the pressure adjusting device  1  of the first preferred embodiment of the present invention includes a main member  10 , a movable member  20 , a fixed member  30 , and an elastic member  40 . 
     The main member  10  is a barrel-like member, having a first opening  12  and a second opening  14  at opposite ends thereof. In the first preferred embodiment, the main member  10  has a first plug  13  inserted into the end of the main member  10 , and the first plug  13  is provided with the first opening  12 . The main member  10  further has a second plug  15  inserted into the other end of the main member  10 , and the second plug  15  is provided with the second opening  14 . The second opening  14  is a threaded hole. 
     The movable member  20  is movably received in the main member  10 . In the first preferred embodiment, the movable member  20  has a first stop block  22  which is larger than the first opening  12 . The movable member  20  has an end extending out of the main member  10  through the first opening  12 , and the first stop block  22  still is received in the main member  10  and restricted by the first plug  13 . The movable member  20  further has a first connector  24  on a back of the first stop block  22 . The movable member  20  has a connecting portion  26  at an end extending out of the main member  10 , and the connecting portion  26  is a slot to engage the plunger  56 . 
     The fixed member  30  is fixed to the main member  10 . In the first preferred embodiment, the fixed member  30  has a threaded section  32  and a second stop block  34  at an end thereof. The fixed member  30  has an end extending out of the main member  10  through the second opening  14 , and the second stop block  34  still is received in the main member  10  and restricted by the second plug  15 . It is noted that the threaded section  32  of the threaded section  32  of the fixed member  30  is threaded with the second opening  14  of the threaded hole, so that the fixed member  30  is fixed to the main member  10  and can be shifted by turning the fixed member  30 . The fixed member  30  is connected to the output bar  54  with the end out of the main member  10 . The fixed member  30  further has a second connector  36  at a back of the second stop block  34  and facing the first connector  24 . 
     The elastic member  40  is a compression spring in the first preferred embodiment. The elastic member  40  is received in the main member  10 , and has opposite ends engaging the first connector  24  and the second connector  36 . The elastic member  40  urges the movable member  20  to make the first stop block  22  against the first plug  13  in a normal condition. 
     The pressure adjusting device  1  of the first preferred embodiment further has an auxiliary holder  38  to fix the fixed member  30  to the main member  10 . The auxiliary holder  38  is a nut in the first preferred embodiment to be threaded onto the fixed member  30  and abutted against the main member  10  or the second stop block  15 . 
     When a user levers the handle  58  to move the pressure adjusting device  1  and the plunger  56  toward a workpiece  3 , the elastic member  40  will be compressed for a specified deflection according to a thickness of the workpiece  3 . For example, the deflection of the elastic member  40  is small when a thin workpiece  3  is fixed, as shown in  FIG. 4 , and the deflection of the elastic member  40  is large when a thick workpiece  3  is fixed. 
     In conclusion, the elastic member  40  will be compressed for a specified deflection according to a thickness of the workpiece  3  so that the quick fixture  2  with the pressure adjusting device  1  can fix the workpieces with different thicknesses. 
     It is easy to understand that the pressure adjusting device  1  can be applied to different types of quick fixtures. For example,  FIG. 6  shows a horizontal type quick fixture  2 ′ with the pressure adjusting device  1 , and  FIG. 7  shows a push-pull type quick fixture  2 ″ with the pressure adjusting device  1 . The functions and operations of the quick fixtures  2 ′ and  2 ″ are the same. 
       FIG. 8  shows a latch type quick fixture  2 ′″ with a pressure adjusting device  1 ′ of the fourth preferred embodiment.  FIG. 9  and  FIG. 10  show a detail of the pressure adjusting device  1 ′ of the fourth preferred embodiment, which is the same as the pressure adjusting device  1  of the first preferred embodiment, except that the elastic member  40  is a tension spring with opposite ends hooked to a first bore  241  on the first connector  24  of the movable member  20  and a second bore  361  on the second connector  36  of the fixed member  30 . 
     The elastic member  40  draws the movable member  20  in the main member  10  in a normal condition, and can be pulled out when the handle  58  is levered to adjust the plunger  56  according to a thickness of a workpiece to be fixed. 
     As shown in  FIG. 11 , a pressure adjusting device  1 ″ of the fifth preferred embodiment includes a main member  70 , a fixed member  80 , a movable member  90 , and an elastic member  99 . The main member  70  has a first opening  72  and a second opening  74  at opposite end, and an inner threaded section  741  on an interior side of the main member  70 . The first opening  72  is smaller than second opening  74 . 
     The fixed member  80  is a barrel-like member having a first outer threaded section  82  on an exterior side thereof. The fixed member  80  is fixed to the main member  70  by meshing the first outer threaded section  82  with the inner threaded section  741  through the second opening  74 . The fixed member  80  has a connecting portion at an end out of the main member  70  to connect a plunger  84 . 
     The movable member  90  has a second outer threaded section  92  and a stop block  94  at opposite ends thereof. The stop block  94  is larger than the first opening  72 . The end with the second outer threaded section  92  of the movable member  90  extends out of the main member  70  through the first opening  72 to connect an output bar of a quick fixture (not shown), and the stop block  94  is received and restricted in the main member  70 . 
     The elastic member  99  has opposite end urging the fixed member  80  and the movable member  90 , so that the elastic member  99  will be compressed by the movable member  90  with a specified deflection according to a thickness of s workpiece to be fixed. The functions and operations of the pressure adjusting device  1 ″ of the fifth preferred embodiment are the same as above, and the pressure adjusting device  1 ″ of the fifth preferred embodiment is able to be incorporated in any type of the quick fixtures as described above. 
     It must be pointed out that the embodiments described above are only some preferred embodiments of the present invention. All equivalent structures which employ the concepts disclosed in this specification and the appended claims should fall within the scope of the present invention.