Abstract:
A pneumatic motor with built-in striker mechanism mainly includes a cylinder, rotor set and output shaft lever. The rotor set has a rotary drum and flexible blades. The output shaft lever can be driven by the rotary drum. A chamber is formed into the rotary drum and a striking portion on the output shaft lever is located within the chamber. The built-in striker mechanism is placed in the chamber and has striking bulges protruded on the striking portion, movable hammers sleeved externally on the striking bulge and struts axially located on the rotary drum. This new pneumatic motor has the striker mechanism set into the rotary drum of the rotor set, thus reducing greatly the axial length and volume of the pneumatic motor and realizing ease-of-use.

Description:
CROSS-REFERENCE TO RELATED U.S. APPLICATIONS 
     Not applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT 
     Not applicable. 
     REFERENCE TO AN APPENDIX SUBMITTED ON COMPACT DISC 
     Not applicable. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to a pneumatic tool structure, and more particularly to an innovative one which is designed into a pneumatic motor with built-in striker mechanism. 
     2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98 
     The pneumatic tools, such as pneumatic spanners, are mainly applied, to screwing or loosening of big nuts and screws. As big nuts and screws requite extremely high torque for locking or loosening, relatively high torque required by themselves will be generated. Said pneumatic spanner&#39;s torque is often generated by a set of striker mechanism. According to the construction and operating principle of said striker mechanism, two massive hammers are set securely into a hammer holder. Said hammer could generate continuously inertia swinging for enhanced hammering torque along with the clockwise and counterclockwise rotation of a driving shaft. 
     The following shortcomings are still observed during actual applications: 
     Said striker mechanism is structured in a way that as front reversing enclosure of certain axial length is set additionally at front end of the pneumatic motor of the pneumatic tool. The front reversing enclosure is used to install and accommodate the hammer holder, massive hammer and rotating shaft of said striker mechanism. However, since the striker mechanism is protruded at the front end of the pneumatic motor, this increases greatly the axial length and volume of the pneumatic tool body, such that the protruding length formed from the end of output shaft to the handle is extended markedly, leading to higher load tier the users and inconvenience in use. As for the manufacturers, the substantial increase of the axial length and volume could results in much higher cost of the materials, manufacturing, assembly and packaging with poorer economic efficiency. 
     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. 
     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 
     Based on the innovative design of “a pneumatic motor with built-in striker mechanism” of the present invention wherein a chamber is formed in the rotary drum of the rotor set, a striking portion on the output shaft lever is located within the chamber, and the built-in striker mechanism is placed in the chamber, the present invention provides at novel pneumatic motor with a striker mechanism set into the rotor set&#39;s rotary drum, thus reducing markedly the axial length and volume of the pneumatic motor. In this way, the protruding length from the output shaft lever&#39;s outer shaft end of the pneumatic tool to the handle could be obviously shortened, enabling the users to hold and operate it more easily with better advantages. Moreover, the striker mechanism has advantages such as: direct driving by the rotor set, instant torque lifting and fast unlocking of components, etc; as the striker mechanism is set into the rotary drum of the rotor set, the axial length and volume of the pneumatic motor could be obviously reduced, so the volume of related components could be cut down, thus saving substantially the cost of materials, manufacturing, assembly and packaging with better economic benefits. 
     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 
         FIG. 1  is an exploded perspective view of preferred embodiment of the present invention. 
         FIG. 2  is another exploded perspective view of the preferred embodiment of the present invention. 
         FIG. 3  is a combined plane view (lateral view) of the preferred embodiment of the present invention. 
         FIG. 4  is another combined plane sectional view (end view) of the preferred embodiment of the present invention. 
         FIG. 5  is a schematic view of another preferred embodiment of the present invention showing the screwing state of the rotary drum and the front/rear panels. 
         FIG. 6  is a schematic view of the present invention wherein the axial length of the pneumatic motor is shorter than that in prior art. 
         FIG. 7  is an exploded sectional view of another preferred embodiment of the present invention showing the structural pattern of the cylinder and rotary drum. 
         FIG. 8  is a combined sectional view of another preferred embodiment of the present invention showing the structural pattern of the cylinder and rotary drum. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIGS. 1-4  depict preferred embodiments of the pneumatic motor of the present invention with built-in striker mechanism, which, however, are provided for only explanatory objective. Said motor A for a pneumatic tool is installed, into the main body  12  formed at one end of the handle  11  of a pneumatic tool  10  (at top in this preferred embodiment). Referring to  FIG. 3 , the handle  11  mainly consists of an inlet channel  111 , exhaust channel  112  and a switch  113  used to control the on-off state of the inlet channel  111   
     Said pneumatic motor A comprises a cylinder  20 , designed into a hollow casing, and comprising: a front wall  21 , a rear wall  22  and a reservoir  23  located internally. The front wall  21  is provided with a front bearing  215 , and the rear wall  22  with a rear bearing  225 . 
     A rotor set  30  is rotarily set into the reservoir  23  of the cylinder  20 . Said rotor set  30  comprises a rotary drum  31  and multiple flexible blades  32  set at interval on the peripheral wall of the rotary drum  31 . Said rotary drum  31  comprises a front panel  33  and a rear panel  34 , of which a front convex shaft  331  is set at center of the from panel  33  for screwing onto the front bearing  215 , and a rear convex shaft  341  is set at center of the rear panel  34  for screwing onto the rear bearing  225 . Moreover, external ends of the flexible blades  32  are shiftably abutted on to inner wall of the reservoir  23 . 
     A chamber  40  is formed into the rotary drum  31  of the rotor set  30 . Said chamber  40  is preferably designed into a cylindrical space. 
     An output shaft lever  50  is provided and comprises a driven end  51 , an outer shaft end  52  and a striking portion  53  located between the driven end  51  and the outer shaft end  52 . The driven end  51  is located on the rear panel  34  of the rotary drum  31  on the rotor set  30 , the output shaft lever  50  could be driven simultaneously with the rotary drum  31 . The outer shaft end  52  penetrates the front convex shaft  331  on the front panel  33  of the rotary drum  31 , then extends out of the front end of the main body  12  of the pneumatic tool  10 . The striking portion  53  is located in the chamber  40  of the rotary drum  31 . Of which, the driven end  51  is combined with the rear panel  34  by means of toothed meshing, polygonal insertion or tangential mating. 
     A built-in striker mechanism  60  is set into the chamber  40  formed by the rotary drum  31  of the rotor set  30 , and comprises: at least a striking bulge  61  protruded on the striking portion  53  of the output shaft lever  50 , at least a movable hammer  62  sleeved externally on the striking bulge  61  and at least a strut  63  axially located between the front and rear panels  33 ,  34  of the rotary drum  31  for supporting and limiting the movable hammer  62 . The chamber  40  is provided with a relief portion  64  only for the motion of the movable hammer  62  (only marked in  FIG. 4 ). 
     At least a driving slot  315  (marked in  FIGS. 2 and 4 ) is recessed into at least a lateral wall of the chamber  40  of the rotary drum  31 , such that one side of said strut  63  could be inserted and driven simultaneously by the rotary drum  31 . 
     As for the rotor set  30  with rotary drum  31  and flexible blades  32 , the locking hole  71  and screw hole  72  are set correspondingly between the rotary drum  31  and its front/rear panels  33 ,  34  for screwing securely by bolts  73 . Of which, said bolts  73  are screwed axially or radially. Referring to  FIG. 2 , said bolts  73  are screwed axially. Referring also to  FIG. 5 , said bolts  73  are screwed radially. Alternatively, said bolts  73  are screwed globally or partially by interpolation of pins  74  (marked in  FIG. 2 ). 
     Of which, said pneumatic tool  10  is a pneumatic spanner, which allows the pneumatic motor A to be transversely set on top of the handle  11 . The axial direction of the output shaft lever  50  is staggered in relation to or set in a direction perpendicular to the extension of the handle  11 . 
     Based on the above-specified structural design, the present invention is operated as follows: 
     Referring to  FIG. 3 , said pneumatic tool  10  is activated in a way that the user could open the inlet channel  111  by pressing the switch  113 , and air pressure (indicated by W) is guided into the reservoir  23  in the cylinder  20  of the pneumatic motor A. This could drive the rotation of the flexible blades  32  of the rotor set  30  along with the rotary drum  31 , and air pressure is then released from the exhaust channel  112 , forming the pneumatic operating path of the pneumatic tool  10 . 
     The core aspect of the present invention lies in its spatial pattern and technical characteristic wherein a chamber  40  is formed in the rotary drum  31  of the rotor set  30  to accommodate the striker mechanism  60 . With this design, the rotary drum  31  of the rotor set  30  is taken as the framework of the built-in striker mechanism  60 , whilst the driving slot  315  set on the lateral wall of the chamber  40  of the rotary drum  31  is used for driving the strut  63  and built-in striker mechanism  60 . Hence, the “front reversing enclosure” in the prior art could be eliminated, thus reducing markedly the axial length and volume of the pneumatic motor and shrinking the volume of related components. Referring to  FIG. 6 , the section marked by L1 refers to the installation portion of the striker mechanism of conventional pneumatic tool and the protruding length formed therein. The section marked by L2 refers to the protruding length formed by the built-in striker mechanism  60  adopted by the pneumatic tool of the present invention. It can thus be seen that the protruding length of the present invention&#39;s pneumatic tool at front of the handle is reduced by about 3-5 cm (depending on the dimension of the pneumatic tool). 
     Of which, more than five flexible blades  32  are set on the rotary drum  31  of the rotor set  30 . The quantity of the flexible blades  32  is determined by the technical characteristics of said built-in striker mechanism  60 . In the prior art, at most six flexible blades are set on the rotor set of of conventional pneumatic tool. However, as a chamber  40  must be formed in the rotary drum  31  of the rotor set  30  to accommodate the built-in striker mechanism  60  in the present invention, the radial height of the flexible blades  32  set externally on the rotary drum  31  must be reduced slightly to meet the maximum space requirements of the chamber  40 . With the reduction of the radial height of the flexible blades  32 , the protruding height is shortened, leading to larger disparity of the air compression space&#39;s length to height ratio. So this problem could be resolved by adding the quantity of the flexible blades  32 . On the other hand, as the reduction of the radial length of the flexible blades  32  may lead to smaller air compression space, the axial length of the flexible blades  32  could be properly prolonged to resolve this problem. 
     Referring also to  FIGS. 7, 8 —another preferred embodiment of the cylinder and rotary drum, the cylinder  20 B and the front wall  21  (or rear wall  22 ) are prefabricated, or the cylinder, the front and rear walls are prefabricated, and a removable assembly portion is formed on the cylinder. This differs from  FIG. 1  wherein the cylinder  20  and the front/rear walls  21 ,  22  are screwed securely. As for the rotor set  30 B in the preferred embodiment, the rotary drum  31  and the front panel  33  (or rear panel  34 ) are prefabricated; this differs from  FIG. 1  wherein the rotary drum  31  of the rotor set  30  and the front/rear walls  21 ,  22  are screwed securely. Besides, the cylinder  20 B and the front wall  21  or rear wall  22 , or the rotary drum  31  and the front panel  33  or rear panel  34  could be assembled securely by bolting or by abutting, and then located finally by the locking of the end wall of the main body  12 . Or, the rotary drum of the rotor set and the front/rear panels are integrally assembled, and then a removable assembly portion is formed on the rotary drum.