JP6382167B2 - Impact tool - Google Patents

Description

  The present invention relates to a striking tool such as an air hammer, for example, which strikes a tip tool such as a chisel with a reciprocating piston so as to apply a striking force to a workpiece that is a workpiece. The present invention relates to an impact tool having an anti-vibration function that suppresses shocking vibration that occurs as a result of the application.

Conventionally, as an impact tool, for example, there is an air hammer 101 as shown in FIG.
The air hammer 101 includes a handle 102 that can be grasped by a human hand, a cylindrical outer peripheral wall 103 provided integrally with the handle 102, and a tool main body 104 that is fitted to and attached to the cylindrical outer peripheral wall 103. And a tip tool 105 such as a chisel that is detachably attached to the tool main body 104.

The tool main body 104 includes a striking force generation unit 106 that generates a striking force, and a holding casing 107 that holds the striking force generation unit 106.
The striking force generator 106 extends in the direction of the cylinder axis (the dashed line indicated by the symbol L in FIG. 3) (hereinafter simply referred to as “cylinder axis”), and is coaxial with the cylinder 110. And a valve box portion 111 integrally incorporated in the base end portion of the cylinder portion 110, and a piston 112 is inserted into the cylinder portion 110 so as to be reciprocable in the cylinder axial direction. A guide bush 113 is press-fitted into the cylinder part 110 so as to be coaxial with the main body 114, and a main valve 114 for switching the reciprocating motion of the piston 112 is disposed in the valve box part 111.

  The tip tool 105 includes a tip tool main body 121 that is pressed against a workpiece that is a workpiece, and an insertion portion 122 that is inserted into the guide bush 113 is integrally formed on the base end side of the tip tool main body 121. When the insertion portion 122 is inserted into the guide bush 113 from the base end of the guide bush 113 to a predetermined protruding amount at the boundary portion between the insertion portion 122 and the tip tool main body portion 121, the difference An abutting portion 123 that abuts on the guide bush 113 is formed so as to stop the further movement of the inserting portion 122 in the insertion direction.

  The handle 102 is formed with an air supply passage 125 that guides compressed air supplied from the outside to the striking force generator 106 and an air exhaust passage 126 for exhausting used compressed air from the striking force generator 106. In addition, an open / close valve 128 that opens and closes the air supply passage 125 by operating the operation button 127 is incorporated.

When using the air hammer 101, the operator lifts the air hammer 101 by grasping the handle 102, aims at the work, and presses the tip tool 105. At this time, the pressing force for pressing the tip tool 105 against the workpiece is transmitted from the cylinder portion 110 in the tool body 104 to the tip tool main body 121 via the guide bush 113 and the contact portion 123.
When the air supply passage 125 is opened by the opening / closing valve 128 by the operation of the operation button 127, compressed air is supplied to the striking force generator 106, and the piston 112 reciprocates by the switching operation of the main valve 114, By striking the portion of the insertion portion 122 of the tip tool 105 protruding from the base end of the guide bush 113 with the reciprocating piston 112, a striking force can be continuously applied to the workpiece via the tip tool 105. For example, rivets can be crimped or cut.

  As the impact force is continuously applied to the workpiece via the tip tool 105, shock vibration is generated. In order to prevent such shock vibration from being directly transmitted to the operator, the air hammer described above is used. In 101, a plurality of O-rings 129 for absorbing vibration are fitted on the outer periphery of the holding casing 107, and the cylindrical outer wall 103 provided integrally with the handle 102 and the tool body 104 are interposed between them. By interposing these O-rings 129, shocking vibrations that are transmitted from the tool 105 to the handle 102 via the cylindrical outer peripheral wall 103 from the tool body 104 through the guide bush 113 are absorbed by the O-ring 129. (See, for example, Patent Document 1).

Japanese Utility Model Publication No. 62-9021

  However, the air hammer 101 described above has a problem that although the shocking vibration to be transmitted to the handle 102 is reduced to some extent by the plurality of O-rings 129, the reduction effect is insufficient.

  The present invention provides an impact tool that can significantly reduce the impact vibration that occurs when a striking force is continuously applied to a workpiece, which is a workpiece, in view of the problems of the conventional impact tool. The purpose is to do.

In order to achieve the above object, the impact tool of the present invention includes a cylinder part, a piston inserted into the cylinder part so as to be able to reciprocate, a cylinder part arranged at the tip of the piston and coaxial with the cylinder part. A guide bush incorporated into the workpiece, a tip tool main body portion pressed against a workpiece that is a workpiece, an insertion portion that extends to the proximal end side of the tip tool main portion and is inserted into the guide bush, and the insertion portion. It has an abutting portion that abuts on the guide bush so as to stop the further movement of the insertion portion in the insertion direction when it is inserted into the guide bush from the base end of the guide bush until a predetermined protruding amount is reached. A tipping tool that reciprocates the insertion part of the tip tool while transmitting the pressing force for pressing the tip tool against the workpiece from the cylinder part to the main part of the tip tool via the guide bush and the contact part. In striking tool which is adapted to strike with down added continuously striking force to the workpiece, the interior of said guide bush, capable of vibrating cylinder unit with contact with the tool bit in the cylinder axis direction in the abutting portion of the tool bit incorporated, a first bushing, to the first bushing disposed in spaced in the cylinder axis direction, constituted by a second bushing slidably supporting the receptacle section of the tool bit, An annular plate-shaped vibration isolating member for absorbing vibration is disposed between the first bushing and the second bushing, and the rear end surface of the first bushing is supported by the front surface of the vibration isolating member. The back surface of the vibration isolating member is supported by the first stepped surface formed in the tip surface of the second bush and the cylinder portion, and the base end surface of the second bush is formed in the cylinder portion. The second stepped surface is supported .

  According to the striking tool of the present invention, the guide bush for guiding the tip tool and transmitting the pressing force for pressing the tip tool against the work to the tip tool is brought into contact with the abutting portion of the tip tool and together with the tip tool in the cylinder axial direction. A first bush that is incorporated in the cylinder portion so as to be capable of vibrating, and a second bush that is disposed at a distance from the first bush in the cylinder axial direction and that slidably supports the insertion portion of the tip tool. The anti-vibration member for absorbing vibration is disposed between the first bushing and the second bushing, so that the tip tool is struck by the reciprocating piston and the workpiece is struck. Impact vibration generated when a force is applied is transmitted from the tip tool to the vibration isolation member via the first bushing, and the shock vibration is absorbed by the vibration isolation member. As you add Shocking vibration can be significantly reduced.

  The back surface of the vibration isolating member is supported by a first stepped surface formed on the tip surface of the second bush and the cylinder portion, and a second end surface of the second bush formed on the cylinder portion. By supporting by the stepped surface, the shock vibration received by the vibration isolator is dispersed and absorbed by the first stepped surface formed on the tip surface of the second bush and the cylinder part. Further, it is possible to more reliably reduce the shocking vibration that occurs as the impact force is applied to the workpiece.

It is a longitudinal section of an impact tool (air hammer) concerning one embodiment of the present invention. It is the A section enlarged view of FIG. It is a longitudinal cross-sectional view of the conventional impact tool (air hammer).

Next, an embodiment of the impact tool of the present invention will be described based on the drawings.
In addition, although embodiment described below is an example in which this invention was applied to the air hammer which is a kind of impact tool, it is not limited to this.

<Description of schematic configuration of air hammer>
An air hammer 1 shown in FIG. 1 is fitted and attached to a handle 2 that can be grasped by a human hand, a cylindrical outer peripheral wall 3 provided integrally with the handle 2, and a cylindrical outer peripheral wall 3. A tool main body 4 and a tip tool 5 such as a chisel that is detachably attached to the tool main body 4.

<Description of tool body>
The tool body 4 includes a striking force generator 6 that generates a striking force and a holding casing 7 that holds the base of the striking force generator 6.
The striking force generating portion 6 is coaxial with the cylinder portion 10 and the cylinder portion 10 extending in the direction of the cylinder axis (the chain line indicated by the symbol L in FIG. 1) (hereinafter simply referred to as “cylinder axis direction”). A valve box portion 11 that is integrally incorporated in the base end portion of the cylinder portion 10 as described above, and a piston 12 is inserted into the cylinder portion 10 so as to be able to reciprocate in the cylinder axial direction. A guide bush 13 is incorporated in the cylinder portion 10 so as to be coaxial with the main body 14, and a main valve 14 for switching the reciprocating motion of the piston 12 is disposed in the valve box portion 11.

<Description of handle>
The handle 2 is formed with an air supply passage 15 for guiding compressed air supplied from the outside to the striking force generator 6 and an air exhaust passage 16 for exhausting used compressed air from the striking force generator 6. In addition, an opening / closing valve 18 for opening and closing the air supply passage 15 by operating the operation button 17 is incorporated.

  As in the prior art, a plurality of O-rings 19 externally fitted to the outer periphery of the holding casing 7 are interposed between the cylindrical outer peripheral wall 3 provided integrally with the handle 2 and the tool body 4. The O-ring 19 absorbs shocking vibrations that are transmitted from the tool 5 through the guide bush 13 through the tool bush 4 to the handle 2 through the cylindrical outer peripheral wall 3 so as to be attenuated. .

As shown in FIG. 2, the cylinder portion 10 in the impact force generating portion 6 is provided with a built-in hole 20 for incorporating a guide bush 13 and a vibration isolation member 40 described later.
The built-in hole 20 has a large-diameter hole portion 21 having a relatively large inner diameter and a small-diameter hole portion 22 having an inner diameter smaller than that of the large-diameter hole portion 21, and the large-diameter hole portion 21 and the small-diameter hole portion 22 are connected to the cylinder portion. 10 are formed in the cylinder portion 10 so as to be sequentially continued from the distal end to the proximal end side, and the first stepped surface 23 is provided at the boundary position between the large diameter hole portion 21 and the small diameter hole portion 22. A second stepped surface 24 is formed at each base end position of the portion 22.

<Description of guide bush>
The guide bush 13 includes a first bush 31 and a second bush 32.

<Description of first bush>
The first bush 31 has an outer diameter larger than the outer diameter of the conventional guide bush 113 (see FIG. 3), and is set to a shape dimension shorter in the axial direction than the guide bush 113. The first bushing 31 is disposed so that the base end surface of the first bush 31 is located at a predetermined distance from the first stepped surface 23 in the cylinder axial direction, and is slidable in the cylinder axial direction. Built in.
A female tapered surface 33 is formed on the inner periphery of the distal end of the first bush 31 so as to expand toward the outside.
A long hole 34 having a predetermined depth is provided on the outer peripheral surface of the first bush 31, and a retaining pin 35 is inserted into the long hole 34 so as to be retained in the cylinder portion 10.
A predetermined gap is provided in the cylinder axial direction between the elongated hole 34 and the retaining pin 35, while allowing the first bush 31 to vibrate with an amplitude within a certain range in the cylinder axial direction. When the first bush 31 is about to fall out of the cylinder portion 10, the retaining pin 35 is caught in the elongated hole 34 to prevent the first bush 31 from falling out of the cylinder portion 10.

<Description of the second bush>
The second bush 32 is set to have an outer diameter equivalent to the outer diameter of the conventional guide bush 113 (see FIG. 3) and a shape shorter in the axial direction than the guide bush 113. The stepped surface 23 and the tip end surface of the second bush 32 are flush with each other, and the base end surface of the second bush 32 is abutted against and supported by the second stepped surface 24 of the assembly hole 20. Thus, it is incorporated into the small-diameter hole 22 by press fitting.

<Description of vibration isolation member>
Between the first bush 31 and the second bush 32, a vibration isolating member 40 for absorbing vibration is disposed.
The vibration isolator 40 includes a center hole 41 through which an insertion portion 52 (described later) of the tip tool 5 can be inserted, a one side plate surface (tip surface) 42 that contacts the base end surface of the first bush 31, 2 simultaneously contacts both the front end surface of the bush 32 and the first stepped surface 23 of the mounting hole 20, and contacts the other side plate surface (back surface) 43 to be supported and the inner peripheral surface of the large-diameter hole portion 21. For example, an anti-vibration rubber having a predetermined thickness and having an outer peripheral surface 44 that elastically deforms when compressed in the cylinder axial direction, for example, an anti-vibration rubber is preferably used.

<Description of tip tool>
The tip tool 5 has a tip tool main body 51 that is pressed against a workpiece (for example, a rivet) that is an object to be processed, and a first tool 31 is passed through a first bush 31 on the base end side of the tip tool main body 51. The insertion part 52 inserted so that it may penetrate the 2 bushes 32 is extended integrally.
A flange 53 is formed at a boundary portion between the tip tool main body 51 and the insertion portion 52.
The flange 53 has a general shape in which a portion near the tip tool main body 51 protrudes outward larger than the outer diameter of the tip tool main body 51, and the outer diameter gradually decreases as it moves toward the insertion portion 52. It has a conical shape and has a contact portion 55 including a male tapered surface 54 that can engage with the female tapered surface 33 of the first bush 31.
The abutting portion 55 includes the second bushing until the insertion portion 52 of the tip tool 5 is inserted into the second bushing 32 through the first bushing 31 and reaches a predetermined protruding amount from the base end of the second bushing 32. The male tapered surface 54 of the abutting portion 55 engages and contacts with the female tapered surface 33 of the first bush 31 when inserted into 32, and the insertion portion 52 moves further in the insertion direction. To stop.

When using the air hammer 1 configured as described above, the operator holds the handle 2 and lifts the air hammer 1 to aim at the work and press the tip tool 5. At this time, the pressing force for pressing the tip tool 5 against the workpiece is transmitted from the cylinder portion 10 to the tip tool main body 51 via the vibration isolating member 40, the first bush 31 and the contact portion 55, and the cylinder portion. 10 is transmitted to the tip tool main body 51 through the second bush 32, the vibration isolator 40, the first bush 31 and the contact portion 55.
When the air supply passage 15 is opened by the opening / closing valve 18 by the operation of the operation button 17, compressed air is supplied to the striking force generator 6, and the piston 12 reciprocates by the switching operation of the main valve 14, The striking force is continuously applied to the workpiece via the tip tool 5 by striking the portion of the insertion portion 52 of the tip tool 5 protruding from the base end of the second bush 32 with the reciprocating piston 12. For example, rivets can be crimped or cut.

As described above, when a striking force is continuously applied to the workpiece via the tip tool 5, a shocking vibration is generated accordingly.
This shocking vibration is transmitted from the tool main body 4 to the handle 2 via the cylindrical outer peripheral wall 3 from the tool main body 51 through the contact portion 55 and the first bush 31. The first bush 31 in contact with the contact portion 55 of the tool 5 is vibrated in the cylinder axial direction together with the tip tool 5, and the vibration is transmitted to the vibration isolation member 40, and the vibration is absorbed by the vibration isolation member 40. Therefore, the shocking vibration that occurs when the impact force is applied to the workpiece can be greatly reduced.
In addition, the vibration motion that the tip tool 5 vibrates in the cylinder axial direction together with the first bush 31 is stably performed by the second bush 32 slidably supporting the insertion portion 52 of the tip tool 5. Therefore, the vibration absorption by the vibration isolating member 40 is smoothly performed.

  In the air hammer 1 of the present embodiment, the one side plate surface 42 of the vibration isolator 40 is brought into contact with and supported by the base end surface of the first bush 31, and the other side plate surface 43 is incorporated into the tip end surface of the second bush 32 and the built-in surface. Since the structure in which both the first stepped surface 23 of the hole 20 is simultaneously contacted and supported is adopted, the other side plate surface 43 of the vibration isolating member 40 is connected to the first stepped surface 23 and the second bushing 32. The vibration of the first bush 31 can be reliably received by the entire one side plate surface 42 of the vibration isolating member 40 while being firmly supported by both of the front end surfaces, and the impact generated when an impact force is applied to the workpiece. Vibration can be absorbed reliably.

  The hitting tool of the present invention has been described based on one embodiment. However, the present invention is not limited to the configuration described in the above embodiment, and the configuration is appropriately changed without departing from the spirit of the present invention. It is something that can be done.

  The striking tool of the present invention has a characteristic that it can greatly reduce the impact vibration that occurs when a striking force is continuously applied to a workpiece that is a workpiece. The present invention can be applied to an air hammer or the like in which a tip tool such as a chisel is struck with a piston reciprocated as a driving source to apply a striking force to the work, and the industrial applicability is great.

1 Air hammer (blow tool)
2 Handle 3 Outer peripheral wall 4 Tool body 5 Tip tool 6 Impact force generating portion 7 Holding casing 10 Cylinder portion 12 Piston 13 Guide bush 20 Assembly hole 21 Large diameter hole portion 22 Small diameter hole portion 23 First stepped surface 24 Second Stepped surface 31 First bush 32 Second bush 40 Anti-vibration member 51 Tip tool main part 52 Insertion part 55 Contact part

Claims (1)

A cylinder part, a piston inserted into the cylinder part so as to be able to reciprocate, a guide bush arranged at the tip of the piston and incorporated in the cylinder part so as to be coaxial with the cylinder part, and a workpiece to be processed The tip tool main body portion to be pressed, the insertion portion extending to the base end side of the tip tool main portion and inserted into the guide bush, and the guide bush until the insertion portion has a predetermined protruding amount from the base end of the guide bush. A tip tool having a contact portion that comes into contact with the guide bush so as to stop further movement of the insertion portion in the insertion direction when inserted into the workpiece, and for pressing the tip tool against the workpiece While the pressing force is transmitted from the cylinder part to the main part of the tip tool via the guide bush and the contact part, the insertion part of the tip tool is struck by a piston that reciprocates to apply a continuous striking force to the workpiece. In Unishi was striking tool, wherein the guide bush is incorporated into the interior of oscillatably cylinder unit the cylinder axis direction together with the tool bit in contact with the contact portion of the tip tool, a first bushing, the first bushing The second bushing is arranged with a gap in the cylinder axis direction and slidably supports the insertion portion of the tip tool, and vibration is generated between the first bushing and the second bushing. An anti-vibration member in the form of an annular plate having the same outer diameter as the first bushing having an outer diameter larger than the outer diameter of the second bushing . The rear end surface of the first bush is supported, and the rear surface of the vibration isolation member is supported by the first stepped surface formed inside the tip surface of the second bush and the cylinder portion, and the base of the second bush. The end surface is supported by the second stepped surface formed inside the cylinder part. Impact tool, characterized in that it was.

Images