Abstract:
A reversing control mechanism of a pneumatic tool includes a rear cover, a reducing through-hole, a diversion seat, a flow switch control seat, a knob portion and a reducing through-hole at rear end of the rear cover trough. The reversing control mechanism is only composed of the rear cover, diversion seat and flow switch control seat, enabling the knob portion to be formed directly onto the rear end of the flow switch control seat. The rear cover, diversion seat and flow switch control seat are coaxially sleeved and located for strong reliability. The knob portion is exposed to the reducing through-hole at rear end of the trough of the rear cover, making convenient operation possible.

Description:
CROSS-REFERENCE TO RELATED U.S. APPLICATIONS 
       [0001]    Not applicable. 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not applicable. 
       NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT 
       [0003]    Not applicable. 
       REFERENCE TO AN APPENDIX SUBMITTED ON COMPACT DISC 
       [0004]    Not applicable. 
       BACKGROUND OF THE INVENTION 
       [0005]    1. Field of the Invention 
         [0006]    The present invention relates generally to a pneumatic tool, and more particularly to an innovative one which is designed with a reversing control mechanism. 
         [0007]    2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98 
         [0008]    The structural design of a pneumatic tool involves three major parts: vane rotor, cylinder and reversing mechanism; of which the reversing mechanisms is used to switch the air inlet/exhaust path/direction of the pneumatic tool, thus changing the rotation of the vane rotor and steering shaft for loosening or locking purpose; the present invention is intended to make some breakthrough progress on the reversing mechanism of the pneumatic tool. 
         [0009]    The reversing mechanism of the existing pneumatic tool is mainly structured in a way that a pneumatic tube is mounted below the pneumatic portion of the pneumatic tool, where a forward/reverse through-hole connected to the air chamber is arranged; besides, the pneumatic tube is connected to the pneumatic source tube; then a movable reversing rod is set into the pneumatic tube, so as to control the reversing action of the air path; yet, the main body of the pneumatic tool is increased with respect to its overall height since a pneumatic tube is mounted below the pneumatic portion of the pneumatic tool; hence, the holding portion will be lowered to deviate from the center of gravity of the pneumatic tool, making it hard to align with the objects due to the shaking of the pneumatic portion. 
         [0010]    In view of the aforementioned problems, another typical structure that allows to mount the reversing mechanism to the near-rear end of the pneumatic portion has been invented, with a reference to ROC patent No. 573594 “a reversing mechanism of pneumatic tool”, wherein a forward/reversing valve is formed into the rear seat of the pneumatic tool with a trough, such that it is capable of switching the direction of air inlet/exhaust; a valve rod hole connected externally is set on the rear seat; besides, another forward/reversing valve rod is arranged near the rear side within the rear seat ; the forward/reversing valve rod is provided with a connecting hole for sleeving onto the protruding rod formed on the center of the forward/reversing valve, enabling the action of the forward/reversing valve with the toggling of the forward/reversing valve rod; notwithstanding such typical pneumatic tool&#39;s reversing mechanism has improved the previous structure, it is still found that no breakthrough improvement has been made, for example, the independent fabrication of the forward/reversing valve rod and then assembly with the forward/reversing valve will result in difficulty in assembly, higher fabrication cost and negative impact on the stability of the overall structure 
         [0011]    Thus, to overcome the aforementioned problems of the prior art, it would be an advancement if the art to provide an improved structure that can significantly improve the efficacy. 
         [0012]    Therefore, the inventor has provided the present invention of practicability after deliberate design and evaluation based on years of experience in the production, development and design of related products. 
       BRIEF SUMMARY OF THE INVENTION 
       [0013]    Based on the innovative structure and technical characteristics of the present invention wherein the “reversing control mechanism of pneumatic tool” mainly comprises: rear cover, reducing through-hole, diversion seat, flow switch control seat, knob portion and reducing through-hole at rear end of the rear cover trough, said reversing control mechanism is only composed of the rear cover, diversion seat and flow switch control seat, enabling the knob portion to be formed directly onto the rear end of the flow switch control seat; besides, the rear cover, diversion seat and flow switch control seat are coaxially sleeved and located for strong reliability; moreover, the knob portion is exposed to the reducing through-hole at rear end of the trough of the rear cover, making it possible for convenient operation; thus the pneumatic tool&#39;s reversing control of the present invention has advantages such as simple construction, robust structure and ease of operation, etc. 
         [0014]    Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0015]      FIG. 1  is an exploded perspective view of the preferred embodiment of the present invention. 
           [0016]      FIG. 2  is another exploded perspective view of the reversing control mechanism of the present invention. 
           [0017]      FIG. 3  is an exploded sectional view of the reversing control mechanism of the present invention. 
           [0018]      FIG. 4  is a combined sectional view of the reversing control mechanism of the present invention. 
           [0019]      FIG. 5  is another combined view of the reversing control mechanism of the present invention when the flow switch control seat is rotated to different angles. 
           [0020]      FIG. 6  is a plane view of the present invention when the knob portion of the flow switch control seat is rotated to preset air closing mode. 
           [0021]      FIG. 7  is a view of  FIG. 6  showing the channel state of the diversion seat and the flow switch control seat. 
           [0022]      FIG. 8  is a plane view of the present invention wherein the knob portion of the flow switch control seat is rotated to first preset air inlet mode. 
           [0023]      FIG. 9  is a view of  FIG. 8  showing the channel state of the diversion seat and the flow switch control seat. 
           [0024]      FIG. 10  is a sectional view of  9  showing the diversion seat exhaust channel. 
           [0025]      FIG. 11  is an air inlet path perspective view of the first preset air inlet mode of the present invention. 
           [0026]      FIG. 12  is an air exhaust path perspective view of the first preset air inlet mode of the present invention. 
           [0027]      FIG. 13  is a plane view of the present invention wherein the knob portion of the flow switch control seat is rotated to second preset air inlet mode. 
           [0028]      FIG. 14  is a view of  FIG. 13  showing the channel state of the diversion seat and the flow switch control seat. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0029]      FIGS. 1-7  depict preferred embodiments of a pneumatic tool&#39;s reversing control mechanism of the present invention, which, however, are provided for only explanatory objective for patent claims. Said reversing control mechanism A is assembled correspondingly to the rear end of the pneumatic portion  11  of the pneumatic tool  10 , enabling to the switch the opening/closing of air pressure path and air inlet/exhaust mode of the pneumatic tool  10 . The reversing control mechanism A comprises:
       a rear cover  20 , comprising an assembly end  21  and a rear side  22 ; said assembly end  21  is assembled at the rear end of the pneumatic portion  11  of the pneumatic tool  10 ; said rear cover  20  is also provided with a trough  23 , at bottom of which an air inlet hole  24  and two exhaust holes  25  are extended to the assembly end  21 ; a first exhaust channel  26  and a second exhaust channel  27  are arranged at left and right sides at top of the trough  23 ;   a reducing through-hole  28 , set at the rear end of the trough  23  of the rear cover  20  for passing through the rear side  22  of the rear cover  20 ;   a diversion seat  30 , comprising a cylinder  31  and an expanding disc  32  set at front end of the cylinder  31 ; of which said cylinder  31  is located into the trough  23  of the rear cover  20 , and the expanding disc  32  is abutted onto the assembly end  21  of the rear cover  20 ; said cylinder  31  is divided into a front section  312  and a rear section  314 ; exhaust channels  33  are set at bottom of the front section  312 , and a punching hole  34  is set at bottom of the rear section  314 ; a first elongated punching channel  35  and a second elongated punching channel  36  are separately arranged on the exterior side of the rear section  314  of the cylinder  31 ; moreover, exhaust holes  352 ,  362  are separately set at upper part of the first and second elongated punching channels  35 ,  36 , and separately linked to the inner upper part of the cylinder  31 ; inlet holes  354 ,  364  are separately set at lower part of the first and second elongated punching channels  35 ,  36 , and separately linked to the inner lower part of the cylinder  31 ; besides, a first air diversion channel  325  and a second air diversion channel  327  are set symmetrically at two sides of the expanding disc  32 ;   a flow switch control seat  40 , which is rotarily assembled into the rear section  314  of the cylinder  31  of the diversion seat  30 ; an exhaust switch groove  41  and an inlet switch groove  42  are separately set at upper and lower sides of the flow switch control seat  40 ; an axial notch  43  recessed backwards is set at front end of the flow switch control seat  40 ; said axial notch  43  is only connected with the exhaust switch groove  41 , and separated from the inlet switch groove  42 ;   of which, a knob portion  44  is formed at the rear end of the flow switch control seat  40 , and located correspondingly to the reducing through-hole  28  at the rear end of the trough  23  on the rear cover  20 , enabling the knob portion  44  to be exposed for convenient control (note: the knob portion  44  can be manually operated through the reducing through-hole  28 ).       
 
         [0035]    Referring to  FIGS. 2, 3 , an expanding limit groove  37  is also set at the rear end of the cylinder  31  of the diversion seat  30 . A limiting notch  38  is set at one side of the expanding limit groove  37 . An expanding ring  45  is set at rear end of the flow switch control seat  40 , and can be accommodated into the expanding limit groove  37 . Moreover, a bulge  46  set at one side of the expanding ring  45  is located into the limiting notch  38 , such that the maximum rotating angle of the flow switch control seat  40  can be implemented as the displacement of the bulge  46  is limited by the limiting notch  38 . 
         [0036]    Referring to  FIGS. 2, 3 , an elastic bead  50  is set on the expanding ring  45  at the rear end of the flow switch control seat  40 , while a plurality of locking flanges  60  are spaced at one side of the expanding limit groove  37  at the rear end of the cylinder  31  of the diversion seat  30 , such that the rotation state of the flow switch control seat  40  could be located sectionally, allowing to identify the opening/closing of air pressure path and air inlet/exhaust mode of the pneumatic tool  10 . 
         [0037]    Of which, the knob portion  44  formed at rear end of the flow switch control seat  40  can be protruded out of the reducing through-hole  28  (shown in  FIGS. 4, 5 ), or located within the reducing through-hole  28 . 
         [0038]    Referring to  FIG. 3 , a plurality of sectional inlet adjusting holes  71 ,  72  are arranged between the inlet hole  354  at lower end of first elongated punching channel  35  of the diversion seat  30  and the punching hole  34  of the diversion seat  30 . The aperture of said sectional inlet adjusting holes  71 ,  72  is smaller than that of the inlet hole  354 . Referring to  FIG. 6 , when the knob portion  44  is rotated to the first inlet mode and located at the first preset section, the channel alignment state of the diversion seat  30  and flow switch control seat  40  is illustrated in  FIG. 7 . In such a case, the inlet switch groove  42  of the flow switch control seat  40  is aligned simultaneously with the punching hole  34  of the diversion seat  30  and either of said sectional inlet adjusting holes  71 . Hence, air pressure guided from the air inlet hole  24  at bottom of the trough  23  of the rear cover  20  will flow through the punching hole  34  and inlet switch groove  42 , then enter into the first elongated punching channel  35  (indicated by arrow in the figure) through the sectional inlet adjusting holes  71 , thus forming an air inlet mode with smaller rotational speed; similarly, when the inlet switch groove  42  is aligned simultaneously with two sectional inlet adjusting holes  71 ,  72 , an air inlet mode with bigger rotational speed could be realized. 
         [0039]    Based upon the above-specified technical characteristics, said reversing control mechanism A is operated as follows. The flow switching of said reversing control mechanism A of the present invention could be realized by the knob portion  44  formed at rear end of the flow switch control seat  40 . When the knob portion  44  is rotated to a preset inlet closing mode, the inlet switch groove  42  of the flow switch control seat  40  is only aligned with the punching hole  34  of the diversion seat  30 . Hence, air pressure guided from the air inlet hole  24  at bottom of the trough  23  of the rear cover  20  could only reach the inlet switch groove  42  through the punching hole  34 , thus forming an air inlet closing state. Referring also to  FIG. 8 , the knob portion  44  is rotated to the first preset air inlet state, wherein the channel alignment state of the diversion seat  30  and flow switch control seat  40  is indicated by the thick broken arrow in  FIGS. 9, 11 . In such a case, the inlet switch groove  42  of the flow switch control seat  40  is aligned simultaneously with the punching hole  34  of the diversion seat  30  and the inlet hole  354  of the first elongated punching channel  35 . Hence, air pressure guided from the air inlet hole  24  at bottom of the trough  23  of the rear cover  20  will flow through the punching hole  34 , then is guided into the pneumatic portion  11  of the pneumatic tool  10  through the inlet switch groove  42  and inlet hole  354  of the first elongated punching channel  35 , and then through the first exhaust channel  26  and first air diversion channel  325 . The exhaust channel is indicated by the thick broken arrow in  FIGS. 9, 10, 12 , wherein air released from the pneumatic portion  11  of the pneumatic tool  10  (only marked in  FIG. 1 ) is guided from the second air diversion channel  327  into the second exhaust channel  27 , then into the exhaust hole  362  of the second elongated punching channel  36  at rear section  314  of the cylinder  31  of the diversion seat  30 , and then through the exhaust switch groove  41  of the flow switch control seat  40  into the axial notch  43 , next into the front end of the trough  23  of the rear cover  20  through the axial notch  43 , and finally released from the exhaust hole  25  at bottom of the trough  23 . When the knob portion  44  is rotated to the second preset air inlet mode as indicated by  FIGS. 13, 14 , the flow state hereto is represented by the left/right mirroring pattern of aforementioned first air inlet mode.