Patent Publication Number: US-2017361446-A1

Title: Shock Absorption Structure of the Pneumatic Tool

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a pneumatic tool, and more particularly to a shock absorption structure of the pneumatic tool. 
     Description of the Prior Art 
     Conventional pneumatic tools contain a reciprocating pneumatic tool and a rotatable pneumatic tool, wherein the reciprocating pneumatic tool contains an impact element pushed by high pressure gas to repeatedly strike a workpiece, and the workpiece is driven to move reciprocately, thus cutting, punching, and drilling the workpiece. 
     With reference to  FIG. 9 , a conventional pneumatic tool contains a grip handle  10 , a gas valve unit  20 , a cylinder  30 , and an impact element  40 , wherein the grip handle  10  is coupled with an air inlet segment  101  configured to flow high pressure gas. The grip handle  10  also includes an air channel  102  communicating with the air inlet segment  101 , a switch (not shown) configured to control the air inlet segment  101 , and a cylindrical portion  103 . The cylindrical portion  103  has a cavity  104  defined therein and communicating with the air channel  102 . The gas valve unit  20  is fixed in the cavity  104  of the cylindrical portion  103 , one end of the cylinder  30  inserts into the cavity  104  of the cylindrical portion  103  so that the cylinder  30  abuts against the gas valve unit  20 . The cylinder  30  includes a sliding room  301  defined therein, a flowing passageway  302  formed between a front end of the sliding room  301  and the gas valve unit  20  so that the front end of the sliding room  301  is in communication with the gas valve unit  20  via the flowing passageway  302 . The impact element  40  is movably accommodated in the sliding room  301  of the cylinder  30 . After turning on the grip handle  10 , the high pressure gas flows into the gas valve unit  20  of the cavity  104  of the cylindrical portion  103  from the air inlet segment  101  of the grip handle  10  via the air channel  102 , hence the high pressure gas is controlled by the gas valve unit  20  flow from a rear end of the sliding room  301  of the cylinder  30  so as to push the impact element  40  to move toward a predetermined position to strike a workpiece (not shown), and the impact element  40  is stopped by the workpiece. Thereafter, the high pressure gas is controlled by the gas valve unit  20  to flow into a front end of the sliding room  301  of the cylinder  30  from the flowing passageway  302  so as to push the impact element  40  to move backward and to strike the gas valve unit  20 , and the impact element  40  is stopped by the gas valve unit  30 , hence the impact element  40  is pushed reciprocately to preform perform a predetermined operation. 
     However, as the impact element  40  of the conventional pneumatic tool is pushed backward to hit the gas valve unit  20 , a reaction force passes toward user&#39;s hands repeatedly to cause using fatigue and to injure user&#39;s wrists. 
     To improve above-mentioned defects, a spring is accommodated in the cavity of the cylindrical portion so as to absorb vibration as the impact element  40  moves backward, thus reducing the reaction force which passes toward the user&#39;s hands. However, the spring cannot effectively reduce the reaction force which passes toward the user&#39;s hands, and the spring produces using fatigue and is replaced frequently. 
     The present invention has arisen to mitigate and/or obviate the afore-described disadvantages. 
     SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a shock absorption structure of a pneumatic tool which contains the cylinder slidably disposed in the cavity of the body, the air chamber is defined in the cavity of the body, the air chamber accommodates the elastic unit, and when the impact element hits the air chamber backward, it drives the cylinder to move in the cavity, and the elastic unit and the air chamber press simultaneously so as to produce double shock absorption and to reduce a reaction force toward the user&#39;s hands, thus operating the pneumatic tool easily and protecting the user&#39;s wrists. 
     Another objective of the present invention is to provide a shock absorption structure of a pneumatic tool which contains the air chamber defined in the cavity of the body, and the air chamber accommodates the elastic unit and mates with the elastic unit so as to press simultaneously and to produce the double shock absorption, hence the elastic unit does not have elasticity fatigue and is not replaced often, after being used repeatedly. 
     Accordingly, a shock absorption structure of a pneumatic tool provided by the present invention contains: a body, a cylinder, a gas valve unit, an impact element, and an elastic unit. 
     The body includes an air channel configured to flow high pressure gas, and the body includes a cavity defined in the body, the cavity has a closing face formed on a first end thereof, and the cavity has an opening defined on a second end of the body opposite to the first end of the cavity. The body also includes a first orifice passing through the cavity, the body includes a second orifice communicating with the air channel and the cavity, and the first orifice accommodates a limitation element, a part of which extends to the cavity. 
     The cylinder is movably fixed in the cavity of the body and a part of the cylinder extends out of the body from the opening of the cavity. The cylinder includes a sliding room defined in the cylinder, and the cylinder includes a contacting fringe arranged on one end of the cylinder facing the closing face of the cavity of the fitting sleeve, the cavity of the body has an air chamber defined between the contacting fringe and the closing face. The cylinder has a defining cutout formed on an outer wall of the cylinder corresponding to the first orifice of the body, and the defining cutout accommodates a part of the limitation element which inserts through the first orifice, hence the cylinder straightly slides forward and backward within a predetermined range. The cylinder also includes an air inlet defined on the outer wall of the cylinder corresponding to the second orifice of the body, and the air inlet is in communication with the second orifice within a sliding range of the cylinder. 
     The gas valve unit is fixed between the sliding room of the cylinder and the contacting fringe so as to control a flowing direction of the high pressure gas. 
     The impact element is disposed in the sliding room of the cylinder and being pushed by the high pressure gas to move reciprocately. 
     The elastic unit includes an elastic pushing force and is secured in the air chamber of the body so as to push against the closing face of the cavity and the contacting fringe of the cylinder and to push the cylinder to move away from the grip handle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing the exploded components of a pneumatic tool in accordance with a preferred embodiment of the present invention. 
         FIG. 2  is a perspective view showing the assembly of a slidable bushing of the pneumatic tool in accordance with the preferred embodiment of the present invention. 
         FIG. 3  is a perspective view showing the assembly of the pneumatic tool in accordance with the preferred embodiment of the present invention. 
         FIG. 4  is a cross sectional view showing the assembly of the pneumatic tool in accordance with the preferred embodiment of the present invention. 
         FIG. 5  is a cross sectional view showing an impact element being pushed forward by a pressure in accordance with the preferred embodiment of the present invention. 
         FIG. 6  is another cross sectional view showing the impact element being pushed forward by the pressure in accordance with the preferred embodiment of the present invention. 
         FIG. 7  is a cross sectional view showing the operation of the pneumatic tool in accordance with the preferred embodiment of the present invention. 
         FIG. 8  is another cross sectional view showing the operation of the pneumatic tool in accordance with the preferred embodiment of the present invention. 
         FIG. 9  is a cross sectional view of a conventional pneumatic tool. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention will be clearer from the following description when viewed together with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiment in accordance with the present invention. 
     With reference to  FIGS. 1 to 4 , a shock absorption structure of a pneumatic tool  100  according to a preferred embodiment of the present invention, the pneumatic tool  100  comprises: a front side  100 A and a rear side  100 B, and the pneumatic tool  100  comprises a body  1 , a cylinder  2 , a gas valve unit  3 , an impact element  4 , and an elastic unit  5 . 
     The body  1  includes an air channel  11  configured to flow high pressure gas, and the body  1  includes a grip handle  12  and a fitting sleeve  13  fitted with the grip handle  12 , wherein the fitting sleeve  13  has a cavity  130  defined therein, the cavity  130  has a closing face  131  formed on a first end thereof and has an opening  132  defined on a second end thereof opposite to the first end of the cavity  130 . The opening  132  has a shoulder  1321  extending inward therefrom, the fitting sleeve  13  has a first orifice  133  passing through the cavity  130  and has a second orifice  134  communicating with the air channel  11  and the cavity  130 , wherein the first orifice  133  accommodates a limitation element  135  which screws with a fixing nut  135   a  and extends to the cavity  130  (In this embodiment, the limitation element  135  screws with the first orifice  133 ). 
     The cylinder  2  is comprised of a slidable bushing  21  and a hollow column  22 , wherein the slidable bushing  21  is movably fixed in the cavity  130  of the fitting sleeve  13 , and the fitting bushing  21  has a hollow portion  210  defined therein, the hollow portion  210  has a closed contacting fringe  211  arranged on one end thereof adjacent to the closing face  131  of the cavity  130  of the fitting sleeve  13 . The cavity  130  of the body  1  has an air chamber  136  defined between the contacting fringe  211  and the closing face  131 , the slidable bushing  21  has an elongated defining cutout  212  formed on an outer wall thereof corresponding to the first orifice  133  of the body  1 , and the defining cutout  212  accommodates a part of the limitation element  135  which inserts through the first orifice  133 , hence the slidable bushing  21  straightly slides forward and backward within a predetermined range and does not rotate. The slidable bushing  21  also has an air inlet  213  defined on the outer wall thereof corresponding to the second orifice  134  of the body  1  and communicating with the hollow portion  210 , and the air inlet  213  is in communication with the second orifice  134  within a sliding range of the slidable bushing  21 , wherein a first end of the hollow column  22  inserts into the hollow portion  210  of the slidable bushing  21  and retains with a bolt  221  in a screwing manner, and the first end of the hollow column  22  is connected with the slidable bushing  21  so that the hollow column  22  moves forward and backward in the cavity  130  of the fitting sleeve  13  with the slidable bushing  21 . A part of a second end of the hollow column  22  extends out of the fitting sleeve  13  so as to connect with a workpiece (not shown) from the cavity  130  of the fitting sleeve  13 , and the hollow column  22  has a sliding room  220 . 
     The gas valve unit  3  is fixed between the hollow column  22  of the cylinder  2  and the contacting fringe  211  of the slidable bushing  21  so that the high pressure gas flows into the gas valve unit  3  from the air channel  11  of the body  1  via the second orifice  134  and the air inlet  213  of the slidable bushing  21 , and the gas valve unit  3  controls a flowing direction of the high pressure gas (the gas valve unit  3  is a prior art, so further remarks are omitted). 
     The impact element  4  is disposed in the sliding room  220  of the hollow column  22  so as to reciprocately move forward and backward, after the impact element  4  is pushed by the high pressure gas. 
     The elastic unit  5  includes an elastic pushing force (in this embodiment, the elastic unit  5  are multiple springs  51  mating with multiple sheaths  52 ) and is secured in the air chamber  136  of the body  1  so as to push against the closing face  131  of the cavity  130  of the body  1  and the contacting fringe  211  of the cylinder  2  and to push the cylinder  2  to move away from the grip handle  12  (the front side  100 A). 
     Referring further to  FIG. 5 , the air channel  11  of the body  1  is opened so that the high pressure gas flows into the gas valve unit  3  from the air channel  11  via the second orifice  134  and the air inlet  213  of the slidable bushing  21 , and the high pressure gas flows into a rear end of the sliding room  220  of the hollow column  22  so as to push the impact element  4  to move toward a front end of the sliding room  220 , hence the impact element  4  hits the workpiece (not shown) and is stopped by the workpiece. As illustrated in  FIGS. 6 and 7 , the high pressure gas is controlled by the gas valve unit  2  to flow into the front end of the sliding room  220  of the hollow column  22  and to push the impact element  4  to move backward toward the rear end of the sliding room  220 , hence the impact element  4  hits the gas valve unit  3  and to drive the cylinder  2  to move backward, wherein the limitation element  135  limits a movement range of the cylinder  2  and to cooperate with the elastic unit  5  so as to press the air chamber  136 , thus producing double shock absorption and reducing reaction force toward user&#39;s hands. Accordingly, the impact element  4  is reciprocately pushed forward and backward to perform a predetermined operation. 
     Referring further to  FIG. 8 , the hollow column  22  of the cylinder  2  has a rotatable adjustment bushing  222  fitted on the outer wall thereof, the rotatable adjustment bushing  222  has at least one air vent  2221  configured to exhaust the gas, and the rotatable adjustment bushing  222  is rotated so as to adjust a gas exhausting position, thus operating the pneumatic tool  100  smoothly. 
     Thereby, the shock absorption structure of the present invention has advantages as follows: 
     1. The cylinder  2  of the shock absorption structure is slidably disposed in the cavity  130  of the body  1 , the air chamber  136  is defined in the cavity  130  of the body  1 , the air chamber  136  accommodates the elastic unit  5 , and when the impact element  4  hits the air chamber  136  backward, it drives the cylinder  2  to move in the cavity  130 , and the elastic unit  5  and the air chamber  136  press simultaneously so as to produce the double shock absorption and to reduce the reaction force toward the user&#39;s hands, thus operating the pneumatic tool  100  easily and protecting the user&#39;s wrists. 
     2. The air chamber  136  is defined in the cavity  130  of the body  1  of the shock absorption structure, and the air chamber  136  accommodates the elastic unit  5  and mates with the elastic unit  5  so as to press simultaneously and to produce the double shock absorption, hence the elastic unit  5  does not have elasticity fatigue and is not replaced often, after being used repeatedly. 
     While we have shown and described various embodiments in accordance with the present invention, it is clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.