Abstract:
A reciprocating pneumatic tool has an integrated module of a cylinder and flow reversing assembly. The tool allows the reversible actuating slot to be recessed integrally onto the air pressure guiding seat. The air pressure guiding seat is separated from the cylinder body via a partition board. Compared with the prior art, the partition board, air pressure guiding seat&#39;s assembly end surface and cylinder body&#39;s inner assembly end can be grinded precisely to realize accurate fitness of various components. The partition board of a planar sheet permits very easy and precise grinding, so the integrated module of cylinder and flow reversing assembly enables simplification of the processing and mass production, reduction of the fabrication/processing cost, and shortening of the assembly time and minimization of the defect with better applicability and industrial benefits.

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 reciprocating pneumatic tool, and more particularly to an innovative one which is designed with an integrated module of a cylinder and flow reversing assembly. 
         [0007]    2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and  37  CFR 1.98. 
         [0008]    Reciprocating pneumatic tools such as pneumatic saws, pneumatic hammers and pneumatic cutters, are available with different functions depending on the shapes of the ends. 
         [0009]    According to the operating principle of reciprocating pneumatic tools, the source of air is firstly guided into the tool, then the opening/closing of air pressure is controlled by a control valve, and an actuating module is used for automatic reversing of air pressure, enabling the reciprocating movement of a piston rod together with the ends of tools (e.g.: saw blade, punch hammer). 
         [0010]    In view of the structural design of the reciprocating pneumatic tool, the number of components affects directly the cost and efficiency of fabrication, processing and assembly, and the defective fabrication and assembly increase with the growing number of components. Thus, due attentions must be paid to the technical issue of minimizing the structural members in the process of R&amp;D and design. 
         [0011]    As for the structural design of a conventional reciprocating pneumatic tool similar to the present invention, Taiwan patent claim No. 96133970: “A Reciprocating Pneumatic Tool” can be referenced, and the general configuration and pattern are shown therein. The flow reversing assembly of the prior art is structurally composed of a top plate, a principal pedestal and a base plate. The flow reversing assembly is superposed onto the surface of a cylinder. It is found from actual applications that the flow reversing assembly of the prior art must be provided with several overlapped plates, and then superposed onto a cylinder. Such an overlapping structure brings about much increase of fabrication, processing and assembly cost of structural members as well as poorer efficiency, meanwhile a higher defect may occur against the performance and quality of finished products. Furthermore, in order to realize accurate fitness and high air-tightness of unit components, the assembly surface of every unit component will be subject to time-consuming and costly precise processing, leading to higher fabrication cost with poorer industrial and economic benefits. 
         [0012]    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. 
         [0013]    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 
       [0014]    The present invention allows the reversible actuating slot to be recessed integrally onto the air pressure guiding seat. Moreover, the air pressure guiding seat is separated from the cylinder body via said partition board. With this unique structural design as compared with the prior art, the partition board, air pressure guiding seat&#39;s assembly end surface and cylinder body&#39;s inner assembly end can be grinded precisely to realize accurate fitness of various components. Of which the partition board of a planar sheet permits very easy and precise grinding, so the integrated module of cylinder and flow reversing assembly enables to simplify the processing and mass production, reduce the fabrication/processing cost, shorten the assembly time and minimize the defect with better applicability and industrial benefits. 
         [0015]    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 
         [0016]      FIG. 1  is an assembled perspective external view of the reciprocating pneumatic tool of the present invention. 
           [0017]      FIG. 2  is an exploded perspective view of the reciprocating pneumatic tool of the present invention. 
           [0018]      FIG. 3  is an exploded perspective view of the integrated module of cylinder and reversing assembly of the present invention. 
           [0019]      FIG. 4  is an assembled sectional view of the reciprocating pneumatic tool of the present invention. 
           [0020]      FIG. 5  is an exploded sectional view of the integrated module of cylinder and reversing assembly of the present invention. 
           [0021]      FIG. 6  is an air inlet schematic view  1  of the present invention. 
           [0022]      FIG. 7  is an air inlet schematic view  2  of the present invention. 
           [0023]      FIG. 8  is air inlet schematic view  3  of the present invention. 
           [0024]      FIG. 9  is an exhaust schematic view of the present invention. 
           [0025]      FIG. 10  is a B-B′ sectional view of  FIG. 9 . 
           [0026]      FIG. 11  is an application view wherein the piston rod guiding tube and cylinder body are assembled fixedly. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0027]      FIGS. 1-5  depict preferred embodiments of an integrated module of cylinder and reversing assembly of a reciprocating pneumatic tool of the present invention, which, however, are provided for only explanatory objective for patent claims. Said integrated module A of cylinder and reversing assembly is arranged between an air supply end  121  of air pressure control module  12  and a guide outlet  131  of piston rod  13  in the groove  11  of reciprocating pneumatic tool  10  (marked in  FIG. 4 ). The piston rod  13  is provided with a piston  132  and a tool assembly portion  133 . 
         [0028]    The integrated module A of cylinder and reversing assembly comprises a cylinder body  20 , a hollow body shaping an inner assembly end  21 , an external end  22 , a cylinder wall  23  and a chamber  24 . Of which, the chamber  24  is used for accommodating the piston  132  of the piston rod  13 . Several air flow ducts  25  are set internally and extended along the cylinder wall  23 . Moreover, air vents  26  are opened laterally onto two opposite sides of the cylinder wall  23 . A reducing piston rod guiding tube  27  is protruded on the external end  22 . 
         [0029]    An air pressure guiding seat  30  has a seat body  31  and an air inlet end  32 . A main air inlet guide hole  33  is penetrated into air inlet end  32  is connected with an air supply end  121  of the air pressure control module  12 . The seat body  31  is provided with an assembly end surface  34 , and flow ducts  35  are set onto two opposite sides of the assembly end surface  34 . Said flow duct  35  is connected obliquely with the main air inlet guide hole  33  via the secondary air inlet guide hole  36 . 
         [0030]    A reversible actuating slot  40  is recessed into the assembly end surface  34  of the seat body  31 , with its inner end connected with the main air inlet guide hole  33 . A lateral through-hole  41  set on the reversible actuating slot  40  runs through the side wall of the seat body  31 . Oblique through-holes  42  set on two sides of the inner wall of the reversible actuating slot  40  run through the assembly end surface  34  of the seat body  31 . Two sides of the reversible actuating slot  40  are connected with the flow duct  35  on the assembly end surface  34 . 
         [0031]    A reversing brake block  50  is accommodated movably into the reversible actuating slot  40 , and reducing flange  51  is formed onto one end of the reversing brake block  50  correspondingly to the reversible actuating slot  40  (shown in  FIGS. 3 ,  5 ), so as to increase the lateral area pushed by air pressure; the lateral through-hole  41  on the reversible actuating slot  40  could maintain smooth lifting of the reversing brake block  50  by releasing air accumulated in the reversible actuating slot  40 . 
         [0032]    A partition board  60  is assembled fixedly between the assembly end surface  34  on the seat body  31  of the air pressure guiding seat  30  and the inner assembly end  21  of the cylinder body  20 . A through-hole  61  of a diameter smaller than external diameter of the reversing brake block  50  is set on the center of the partition board  60 . Two flow troughs  62  spaced onto the partition board  60  are connected with the air flow duct  25  on the cylinder wall  23  of the cylinder body  20  and the oblique through-hole  42  on the seat body  31  of the air pressure guiding seat  30 . 
         [0033]    Referring to  FIG. 3 , a plurality of bolt holes  71 ,  72  are set correspondingly on the air pressure guiding seat  30  and partition board  60 . A positioning threaded hole  73  is set correspondingly to the inner assembly end  21  of the cylinder body  20 , such that the bolt holes  71 ,  72  are fixed by the bolt  74  and locked into the positioning threaded hole  73 , enabling secure assembly of the air pressure guiding seat  30 , partition board  60  and cylinder body  20 . 
         [0034]    Referring to  FIG. 5 , the reversible actuating slot  40  of a stepped recess space is defined into a pinched portion  43  and an flared portion  44 , so that said lateral through-hole  41  is set correspondingly to the flared portion  44 . The reversing brake block  50  comprises of a reduced portion  52  and an expanded portion  53 . The expanded portion  53  is placed correspondingly to the pinched portion  43  of the reversible actuating slot  40 , whilst the reduced portion  52  is mated with the flared portion  44  of the reversible actuating slot  40 . With the design of a stepped pattern, a differential pressure area of bigger top and smaller bottom is formed in response to the actuating flow path design of the reversing brake block  50  (namely, the top is subject to central pressure, and the bottom subject to central and lateral pressure). 
         [0035]    Referring to  FIGS. 2 and 4 , a damper is arranged within the groove  11  of the reciprocating pneumatic tool  10 . Said damper comprises of a central buffer  81  (e.g. a spiral spring) set between the seat body  31  of air pressure guiding seat  30  and air supply end  121  of air pressure control module  12 , as well as a front buffer  82  (e.g. a spiral spring) set between the external end  22  of the cylinder body  20  and an end wall of the groove  11 . 
         [0036]    Of which, the piston rod guiding tube  27  on the external end  22  of the cylinder body  20  and the cylinder body  20  may be prefabricated (shown in  FIGS. 2-9 ), or the piston rod guiding tube  27 B shown in  FIG. 11  is set into an assembled positioning structure, wherein the piston rod guiding tube  27 B and the external end  22  of the cylinder body  20  can be fixed securely by bolt  28 . 
         [0037]    Moreover, the cylinder body  20 , air pressure guiding seat  30  and partition board  60  are provided with trimmed edges  91 ,  92 ,  93 . The inner wall opposite to the groove  11  of the reciprocating pneumatic tool  10  is of cylindrical cross section, such that an exhaust passage  94  is formed between the trimmed edges  91 ,  92 ,  93  and the inner wall of cylindrical groove  11  (shown in  FIGS. 9 and 10 ). 
         [0038]    Based upon above-specified structure, the present invention is operated as follows: 
         [0039]    Referring to  FIG. 6 , said reciprocating pneumatic tool  10  is operated in such a manner that the control switch  14  is pressed (shown by arrow L 1 ) to open air flow path of the air pressure control module  12 . Then air pressure W will pass through air supply end  121  of air pressure control module  12  and air inlet end  32  into air pressure guiding seat  30  and integrated module A of cylinder and reversing assembly. With the help of air flow path design of the integrated module A, the piston  132  and piston rod  13  along with the actuating tool (e.g.: saw) are driven for rapid reciprocating movement with reference to the accompanying drawings. 
         [0040]    Referring firstly to  FIG. 6 , when air pressure W is guided from air pressure guiding seat  30  into the integrated module A of cylinder and reversing assembly, it will pass through the oblique secondary air inlet guide hole  36  and flow duct  35  into the reversible actuating slot  40 . In such a case, air pressure W will push the reversing brake block  50  upwards to drive the top of the reversing brake block  50  to close the main air inlet guide hole  33 , on the other hand, air pressure W passes the through-hole  61  on the center of partition board  60  into the chamber  24  of the cylinder body  20  so as to push the piston  131  downwards. 
         [0041]    Referring also to  FIG. 7 , the sectional position is located at the air flow duct  25  of the cylinder body  20 . When the piston  132  is pushed downwards, air squeezed in the lower space of the chamber  24  will pass through air flow duct  25  on the cylinder wall  23  of the cylinder body  20 , then through the flow through  62  of the partition board  60  and the oblique through-hole  42  of the air pressure guiding seat  30  into the upper part of the reversible actuating slot  40 , thus pushing the reversing brake block  50  downwards (shown by arrow L 2 ). 
         [0042]    Referring also to  FIG. 8 , when the reversing brake block  50  is pushed downwards by air pressure W, air pressure W in main air inlet guide hole  33  can pass through oblique through-hole  42 , then through the flow through  62  of partition board  60 , air flow duct  25  of cylinder body  20  into the lower space of the chamber  24 , thus pushing the piston  132  upwards (shown by arrow L 3 ) for reversing movement. 
         [0043]    Referring also to  FIGS. 9 and 10 , when the piston  132  is pushed to the bottom, exhaust air flow W 2  will be discharged from air vent  26  on the chamber  24  to the exhaust passage  94  reserved on the cylinder body  20 . 
         [0044]    The core design of the present invention lies in that, the reversible actuating slot  40  of the integrated module A is recessed integrally onto the air pressure guiding seat  30 , which is separated from the cylinder body  20  via said partition board  60 , thus simplifying the structural members and facilitating fabrication without changing the functions of guiding, reversing air and actuating the piston.