WO2011001979A1

WO2011001979A1 - Working tool

Info

Publication number: WO2011001979A1
Application number: PCT/JP2010/061061
Authority: WO
Inventors: 光亀谷; 正規古澤
Original assignee: 株式会社マキタ
Priority date: 2009-07-02
Filing date: 2010-06-29
Publication date: 2011-01-06
Also published as: JP5436071B2; JP2011011296A

Abstract

A working tool comprises a tool body (103), to a tip area of which a tip tool (119) can be attached, a handle (109, 211) which is connected to the tool body (103) so as to be relatively movable, and a vibration damping mechanism (171, 221) provided between the tool body (103) and the handle (109, 211). The vibration damping mechanism (171, 221) has a plurality of vibration damping elements (173, 227) which are arranged to be spaced from one another so as to reduce the transmission of vibration between the tool body (103) and the handle (109, 211). The plurality of vibration damping elements (173, 227) are connected to each other by a connecting portion (173a, 227a).

Description

Work tools

The present invention relates to a vibration isolating technique for a work tool that causes a workpiece to perform a predetermined machining operation by driving a tip tool.

Japanese Patent Publication No. 58-34271 discloses an anti-vibration handle structure for an electric hammer. In this known electric hammer, a handle grasped by an operator is connected to a rear end portion of the main body housing opposite to the hammer bit via a vibration isolation mechanism. The anti-vibration mechanism is mainly composed of a plurality of rubbers disposed between the main body housing and the handle. According to the known technique, the vibration of the operator during the machining operation is reduced. On the other hand, when assembling the tool main body and the handle, the plurality of rubbers must be maintained at the arrangement position after the plurality of rubbers are individually arranged between the tool main body and the handle. It is cumbersome and there is room for improvement in this regard.

In view of the above problems, an object of the present invention is to provide a technique that contributes to an improvement in assemblability in a work tool having a vibration isolation mechanism.

In order to achieve the above object, according to a preferred embodiment of the work tool according to the present invention, a tool body in which a tip tool can be attached to a tip region, a handle connected to the tool body so as to be relatively movable, and a tool body And an anti-vibration mechanism provided between the handle and the handle. The “work tool” in the present invention is typically a hammer that performs a hammering operation on a workpiece by hammering a hammer bit as a tip tool in the long axis direction, or hammering and rotating hammer bits. A hammering tool such as a hammer drill that performs a hammer drill operation or the like on a workpiece corresponds to this, but not only the hammering tool but also a work tool that vibrates during the machining operation is preferably included. Further, the “handle” in the present invention corresponds to a main handle, an auxiliary handle (side handle), or a housing with a handle, which is provided for an operator to operate a work tool.

In a preferred form of the work tool according to the present invention, as a characteristic configuration, the vibration isolation mechanism has a plurality of vibration isolation elements that are spaced apart to reduce transmission of vibration between the tool body and the handle, The plurality of anti-vibration elements are connected to each other by a connection portion. The “vibration isolation element” in the present invention typically corresponds to rubber. Moreover, as a mode of connection by the connection portion of the vibration isolation element, typically, a mode in which the vibration isolation element and the connection portion are integrally formed is preferable.

According to the present invention, in the vibration isolating mechanism, a plurality of vibration isolating elements arranged apart from each other are connected to each other by the connecting portion. As a result, a plurality of vibration isolation elements are integrated (one component). For this reason, the number of parts can be reduced and a plurality of vibration isolation elements can be handled as one part. When the tool body and the handle are assembled, the vibration isolation element disposed between the tool body and the handle is It is easy to maintain the position at the position. For this reason, the assemblability when the tool body and the handle are assembled can be improved.

According to the further form of the work tool according to the present invention, all of the plurality of vibration isolation elements are formed in the same outer shape. Here, the same outer shape does not include a size, but means that the shape when viewed from the outside is the same, and is typically formed in a spherical shape or a cylindrical shape.

According to a further aspect of the work tool according to the present invention, the plurality of vibration isolation elements are arranged at equal intervals around the major axis direction of the tool body. By adopting such a configuration, it is possible to obtain a balanced vibration reducing action with respect to the tool body around the longitudinal direction.

According to the further form of the work tool which concerns on this invention, the some vibration isolating element is connected cyclically | annularly by the connection part. By adopting such an annular connection structure, when the vibration isolating element is assembled between the tool body and the handle in an intervening manner, the vibration isolating element can be set so as to be fitted to the peripheral surface of the vibration isolating element arrangement region of the tool main body or the handle. This makes it possible to further improve the ease of handling the vibration isolating element.

According to a further form of the work tool according to the present invention, the handle has a long grip portion extending in a direction intersecting the long axis direction of the tool body. The plurality of vibration isolation elements are arranged symmetrically with respect to the long axis of the grip portion. By setting it as such a line symmetrical arrangement | positioning, the vibration reduction effect | action by a some anti-vibration element can be exhibited with sufficient balance.

According to the present invention, a technique that contributes to an improvement in assemblability is provided in a work tool having a vibration isolation mechanism. Other features, actions, and advantages of the present invention can be readily understood with reference to the specification, claims, and accompanying drawings.

It is sectional drawing which shows the whole structure of the hammer drill provided with the handgrip of the vibration proof structure which concerns on 1st Embodiment of this invention. It is an expanded sectional view which shows the vibration proof structure of a hand grip. FIG. 3 is a sectional view taken along line AA in FIG. 2. FIG. 3 is a sectional view taken along line BB in FIG. It is a figure which shows the vibration isolating structure of the side grip which concerns on 2nd Embodiment of this invention. FIG. 6 is a partially enlarged view of FIG. 5. FIG. 6 is a cross-sectional view taken along the line CC of FIG.

The configurations and methods according to the above and the following descriptions are separately or separately from other configurations and methods in order to realize the manufacture and use of the “work tool” according to the present invention and the use of the components of the “work tool”. Can be used in combination. Exemplary embodiments of the present invention include these combinations and will be described in detail with reference to the accompanying drawings. The following detailed description is only to teach those skilled in the art with detailed information to implement preferred embodiments of the invention, and the scope of the invention is not limited by the detailed description, but is limited by the scope of the claims. It is determined based on the description. For this reason, combinations of configurations and method steps in the following detailed description are not all essential to implement the present invention in a broad sense, but are described in detail with reference numerals in the accompanying drawings. However, only representative embodiments of the present invention are disclosed.
(First embodiment of the present invention)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. This embodiment will be described using an electric hammer drill as an example of a work tool. FIG. 1 is a sectional view showing the overall configuration of the electric hammer drill according to the present embodiment. As shown in FIG. 1, the hammer drill 101 according to the present embodiment is generally viewed as having a main body 103 that forms an outline of the hammer drill 101, and a cylindrical region in the tip region (left side in the drawing) of the main body 103. A hammer bit 119 detachably attached via a tool holder 137 and a hand grip 109 gripped by a user connected to the opposite side of the main body 103 to the hammer bit 119 are mainly configured. The main body 103 corresponds to the “tool main body” in the present invention, the hammer bit 119 corresponds to the “tip tool” in the present invention, and the hand grip 109 corresponds to the “handle” in the present invention. The hammer bit 119 is held by the tool holder 137 so that the hammer bit 119 can be reciprocated relatively in the major axis direction, and the relative rotation in the circumferential direction is restricted. For convenience of explanation, the hammer bit 119 side is referred to as the front, and the hand grip 109 side is referred to as the rear.

The main body 103 is mainly composed of a motor housing 105 that houses a drive motor 111 and a gear housing 107 that houses a motion conversion mechanism 113, a striking element 115, and a power transmission mechanism 117. The gear housing 107 includes a cylindrical barrel portion 106 in front of it. The rotational output of the drive motor 111 is appropriately converted into a linear motion by the motion conversion mechanism 113 and then transmitted to the striking element 115, and the major axis direction of the hammer bit 119 (the left-right direction in FIG. 1) via the striking element 115. Generates an impact force on. The rotational output of the drive motor 111 is transmitted to the tool holder 137 after being appropriately decelerated by the power transmission mechanism 117, and the hammer bit 119 is rotated in the circumferential direction together with the tool holder 137. Below the gear housing 107, the drive motor 111 is disposed vertically so that the rotation axis of the drive motor 111 intersects the long axis of the hammer bit 119. The drive motor 111 is energized and driven by an operator pulling and operating a trigger 109 a disposed on the handgrip 109.

The motion conversion mechanism 113 converts the rotational motion of the drive motor 111 into a linear motion and transmits it to the striking element 115, and is mainly composed of a crank mechanism. The crank mechanism is configured such that a piston 129 as a driver constituting the final movable member of the crank mechanism linearly moves along the inner wall of the cylinder 141 in the hammer bit major axis direction by being rotationally driven by the drive motor 111. Is done. On the other hand, the power transmission mechanism 117 is mainly configured by a gear reduction mechanism including a plurality of gears, and transmits the rotational force of the drive motor 111 to the tool holder 137. As a result, the tool holder 137 is rotated in the vertical plane, and the hammer bit 119 held by the tool holder 137 is rotated accordingly. Note that the specific configurations of the motion conversion mechanism 113 and the power transmission mechanism 117 are not directly related to the present invention and will not be described.

The striking element 115 is mainly composed of a striker 143 as a striking element slidably disposed on the bore inner wall of the cylinder 141 together with the piston 129, and an impact bolt 145 as an intermediate element slidably disposed on the tool holder 137. Composed. The striker 143 is driven via an air spring in the air chamber 141a of the cylinder 141 accompanying the sliding movement of the piston 129, collides with (impacts) the impact bolt 145, and strikes the hammer bit 119 via the impact bolt 145. To communicate.

In the hammer drill 101 configured as described above, when the drive motor 111 is energized and driven, the hammer bit 119 is moved from the motion conversion mechanism 113 configured by the crank mechanism to the major axis direction via the striking element 115. A striking force is applied, and a rotational force in the circumferential direction is applied via a power transmission mechanism 117 constituted by a gear reduction mechanism. Thus, the hammer bit 119 performs a hammering operation in the major axis direction and a drilling operation in the circumferential direction to perform a drilling operation on the workpiece (concrete).
The hammer drill 101 can be performed by appropriately switching between a hammer operation that applies only a striking force in the long axis direction to the hammer bit 119 and a hammer drill operation that applies a striking force in the long axis direction and a rotational force in the circumferential direction. However, since this is not directly related to the present invention, the description thereof is omitted.

At the time of the machining operation by the hammer drill 101, vibration is generated in the main body 103 in accordance with the hammering operation of the hammer bit 119. The main vibration at this time is vibration in the major axis direction of the hammer bit 119. In order to reduce the transmission of vibration generated in the main body 103 to the hand grip 109, the hand grip 109 is connected to the rear end of the main body 103 via the upper and lower

vibration isolation mechanisms

161 and 171.

The hand grip 109 has a grip portion 151 extending in the vertical direction intersecting the major axis direction of the hammer bit 119, and the upper end portion and the lower end portion of the grip portion 151 are generally horizontally directed forward. Protruding connecting

portions

153 and 155 are formed, and the upper and lower connecting

portions

153 and 155 are connected to the cover member 104 covering the rear portion (right side in FIG. 1) of the main body 103 via the upper and lower

vibration isolation mechanisms

161 and 171. Has been. As a result, the handgrip 109 forms a loop-shaped handle (D-shaped handle in a side view) including the cover member 104. The grip portion 151 and the upper and lower connecting

portions

153 and 155 are formed in a hollow shape. As shown in FIG. 1, the cover member 104 is disposed at a rear portion of the main body portion 103, and a plurality of predetermined positions are fixed to the main body portion 103 with screws or the like not shown for convenience. That is, the cover member 104 is a main body side member that is assembled and fixed to the main body 103.

Next, the upper and lower

vibration isolation mechanisms

161 and 171 will be described with reference to FIGS. As shown in FIG. 2, the upper vibration isolation mechanism 161 is mainly configured by a compression coil spring 163 disposed in an intervening manner between the rear portion of the cover member 104 and the front portion of the upper connecting portion 153. The compression coil spring 163 is arranged such that the direction of action (axial direction) of the elastic force substantially coincides with the major axis direction of the hammer bit 119 that is the input direction of vibration. The compression coil spring 163 is placed above a straight line obtained by extending the long axis of the hammer bit 119, one end in the axial direction is supported by the cover member 104, and the other end is supported by the connecting portion 153. The compression coil spring 163 is covered with an elastic rubber dustproof cover 165 disposed between the upper connecting portion 153 and the cover member 104.

As shown in FIGS. 2 to 4, the lower vibration isolation mechanism 171 includes a plurality of (four in the present embodiment) disposed in an intervening manner between the rear portion of the cover member 104 and the front portion of the lower connecting portion 155. A plurality of elastic rubbers 173, an inner rubber receiver 175 formed at the lower rear portion of the cover member 104, an outer rubber receiver 177 formed at the front portion of the lower connecting portion 155, and a plurality (this embodiment) In this case, the four elastic rubber members 173 are connected to each other, and the connecting portion 173a is connected as a main component. The anti-vibration mechanism 171 on the lower side corresponds to the “anti-vibration mechanism” in the present invention, the elastic rubber 173 corresponds to the “anti-vibration element” in the present invention, and the connection portion 173a corresponds to the “connection portion” in the present invention. Corresponding to The four elastic rubbers 173 are formed in a spherical shape having the same size and shape. That is, it is set as the structure which has the same vibration reduction function, and is arrange | positioned between the inner side rubber receiver 175 and the outer side rubber receiver 177 arrange | positioned so that the said inner side rubber receiver 175 may be covered.

The inner rubber receiver 175 has an outer surface shape with a vertically rectangular cross section, and as shown in FIG. 2, the upper outer surface and the lower outer surface thereof are each formed in a tapered shape tapered from the root side toward the rear. Two engagement recesses 175a each having a substantially hemispherical concave shape for holding the elastic rubber 173 are formed on the outer surface and the lower outer surface. The outer rubber receiver 177 covering the inner rubber receiver 175 is formed in a cylindrical shape whose inner surface shape corresponds to the outer surface shape of the inner rubber receiver 175 (however, it does not have a substantially hemispherical concave engaging recess). ing.

As shown in FIG. 3, the four elastic rubbers 173 correspond to a straight line in the vertical direction (vertical direction) that intersects the long axis direction of the hammer bit 119, that is, a straight line in the long axis direction of the grip portion 151 of the hand grip 109. As a whole, the hammer bit 119 is placed at a position lower than a straight line obtained by extending the major axis (see FIG. 1). Each elastic rubber 173 is pressed by the upper and lower inner surfaces (tapered surfaces) of the outer rubber receiver 177 in the radial direction while being fitted in engagement recesses 175a formed on the upper outer surface and the lower outer surface of the inner rubber receiver 175, respectively. It is held in a pinched form. The four elastic rubbers 173 arranged as described above are connected to each other in advance by integral molding at the time of molding. That is, the spherical elastic rubbers 173 according to the present embodiment are configured such that adjacent ones are connected in a substantially square annular shape by a connecting portion 173a having a circular cross section smaller in diameter than the elastic rubber 173.

As shown in FIGS. 2 and 3, two circular through holes 104 a penetrating in the long axis direction of the hammer bit 119 are formed on the cover member 104 side, and the through holes 104 a are long axes of the grip portion 151. It is formed symmetrically across a straight line in the direction. One circular columnar member 155a provided at the lower connecting portion 155 is slidably inserted from the rear side into the left and right through holes 104a. The inserted columnar member 155a is prevented from coming off when the head 179a of the stopper bolt 179 screwed into the columnar member 155a from the cover member 104 side contacts the front surface of the cover member 104 (hole edge of the through hole 104a). Has been. Although not shown for convenience, the upper connecting portion 153 also has a connecting structure using the through hole 104a, the columnar member 155a, and the stopper bolt 179 in the lower connecting portion 155 or a similar structure. Used to connect to the cover member 104. Further, the lower vibration isolating mechanism 171 is covered with a stretchable rubber dust proof cover 181 disposed between the lower connecting portion 155 and the cover member 104, thereby dust or the like entering the vibration isolating mechanism 171. Intrusion is prevented.

In the hammer work or the hammer drill work by the hammer drill 101 configured as described above, an operator who holds the grip part 151 of the hand grip 109 applies a pressing force in the major axis direction of the hammer bit 119 to the main body part 103. While this is done, the hammer bit 119 is pressed against the workpiece. By this pressing, the hand grip 109 approaches the cover member 104 by an amount equivalent to the deformation of the compression coil spring 163 and the elastic rubber 173, and the head 179 a of the stopper bolt 179 is separated from the front surface of the cover member 104.

During the above machining operation, the main body 103 is subjected to shock and periodic vibration in the long axis direction of the hammer bit 119. However, vibration transmission from the main body 103 side to the hand grip 109 side is performed on the upper side. Can be reduced by elastic deformation of the compression coil spring 163, and can be reduced by elastic deformation of the elastic rubber 173 on the lower side.

By the way, the assembly of the hand grip 109 to the cover member 104 is performed by arranging the compression coil spring 163 between the upper connecting portion 153 and the cover member 104, while the columnar member 155 a of the lower connecting portion 155 is inserted into the through hole 104 a of the cover member 104. In addition, the outer rubber receiver 177 is put on the inner rubber receiver 175 fitted with the elastic rubber 173, and then the stopper bolt 179 is screwed into the columnar member 155a. Such assembly is performed before the cover member 104 is assembled to the rear portion of the main body 103. That is, by assembling the handgrip 109 and the cover member 104 in advance, a handgrip assembly connected by the upper and lower

vibration isolation mechanisms

161 and 171 is configured.

In the present embodiment, a plurality of elastic rubbers 173 that are adjacent to each other by integral molding are connected in a ring shape via a connecting portion 173a. For this reason, a plurality of elastic rubbers 173 are integrated (one part), and the number of parts can be reduced. Further, since the plurality of elastic rubbers 173 are formed as one component, the elastic rubber 173 is fitted to the outer peripheral surface of the inner rubber receiver 175 when the hand grip 109 and the cover member 104 are assembled as described above. It can be attached so as to be wound (wrapped) and can be maintained at the position where it is fitted in each engaging recess 175a. That is, since the elastic rubber 173 does not fall off even when the hand is released, the outer rubber receiver 177 of the lower connecting portion 155 can be easily covered with the inner rubber receiver 175, and the assembly of the hand grip 109 with respect to the cover member 104 is possible. Can be improved.

In the present embodiment, the plurality of elastic rubbers 173 are all formed in the same shape, that is, in a spherical shape, and are arranged in line symmetry with respect to the long axis of the grip portion 151. By setting it as such a structure, the vibration reduction effect by the some elastic rubber 173 can be exhibited with sufficient balance. In addition, since the plurality of elastic rubbers 173 are arranged symmetrically with respect to the long axis of the grip portion 151, the assembly direction is not limited to one direction. For this reason, assembly work can be performed easily.

(Second embodiment of the present invention)
Next, a second embodiment of the present invention will be described with reference to FIGS. The present embodiment relates to vibration isolation of the side grip 211 as an auxiliary handle attached to the front region of the main body 103, separately from the hand grip 109 as the main handle disposed behind the main body 103 of the hammer drill 101. It is. The side grip 211 is attached to the barrel portion 106 that constitutes the front region of the gear housing 107.

As shown in FIGS. 5 and 7, the side grip 211 in the present embodiment is a rod-like grip that extends in a direction intersecting with the major axis direction of the hammer bit 119, and one end portion in the major axis direction has a barrel portion 106. And the other end is in a free state. The side grip 211 corresponds to the “handle” in the present invention. The side grip 211 is attached to an annular handle mounting portion 106 a (see FIG. 1) formed on the barrel portion 106 via a vibration isolation mechanism 221. The anti-vibration mechanism 221 corresponds to the “anti-vibration mechanism” in the present invention.

Hereinafter, the vibration isolation mechanism 221 will be described. The anti-vibration mechanism 221 is fitted in a loose fit with an annular inner rubber receiver 223 that is fixedly attached to the handle mounting portion 106a of the barrel section 106, and a predetermined gap outside the inner rubber receiver 223. An annular outer rubber receiver 225, a plurality (six in this embodiment) of elastic rubbers 227 disposed between the inner rubber receiver 223 and the outer rubber receiver 225, and a plurality of elastic rubbers 227 And a connection portion 227a that connects the two to each other. The elastic rubber 227 is formed in a spherical shape having the same size and shape and has the same vibration reduction function. The elastic rubber 227 corresponds to the “vibration isolation element” in the present invention, and the connection portion 227a corresponds to the “connection portion” in the present invention.

The six elastic rubbers 227 are straight lines around the major axis direction of the hammer bit 119 (around the axis lines of the inner rubber receiver 223 and the outer rubber receiver 225) at equal intervals (60 degree intervals) and in the major axis direction of the side grip 211. Are arranged in line symmetry. Each spherical elastic rubber 227 is formed into a substantially hemispherical concave engaging recess 223a formed on the outer surface of the inner rubber receiver 223 and a substantially hemispherical concave engaging recess 225a formed on the inner surface of the outer rubber receiver 225. In the fitted state, it is held in a pinched shape in the radial direction. By being held in this manner, a shearing direction force acts on the elastic rubber 227 in the major axis direction and the circumferential direction of the hammer bit 119, and a force acts mainly in the compression direction in a direction intersecting the major axis direction. It is supposed to be configured.

As described above, the six elastic rubbers 227 disposed between the inner rubber receiver 223 and the outer rubber receiver 225 are connected to each other in advance by integral molding at the time of molding. That is, as shown in FIGS. 5 and 6, the spherical elastic rubber 227 according to the present embodiment is circularly spaced at equal intervals by the connecting portions 227 a having a circular cross section smaller in diameter than the elastic rubber 227. It is set as the structure connected circularly.

Further, as shown in FIGS. 5 and 6, a plurality of protrusions 223 b protrude outwardly on the outer surface of the inner rubber receiver 223, and a plurality of protrusions 225 b inwardly protrude on the inner surface of the outer rubber receiver 225. The

protrusions

223b and 225b are opposed to each other so that they can be engaged with each other with a predetermined gap in the circumferential direction. Accordingly, the inner rubber receiver 223 and the outer rubber receiver 225 can be relatively moved in the circumferential direction by elastic deformation of the elastic rubber 227 within the gap. In other words, both the

protrusions

223b and 225b restrict the relative movement of the inner rubber receiver 223 and the outer rubber receiver 225 beyond the circumferential gap set between the

protrusions

223b and 225b, thereby elastically The elastic rubber 227 is configured to function as a stopper that protects the elastic rubber 227 from excessive circumferential force acting on the rubber 227.

Further, in order to allow the elastic rubber 227 to be assembled between the annular inner rubber receiver 223 and the annular outer rubber receiver 225, the outer rubber receiver 225 is arranged in the radial direction as shown in FIGS. It is constituted by two divided semi-annular divided

bodies

225A and 225B. A locking recess 225c is formed on the mating surface of the one half-circular segment 225A, and a hook-shaped latching piece 225d is formed on the mating surface of the other semi-circular segment 225B. Is formed. Therefore, when the two divided

bodies

225A and 225B are put on the inner rubber receiver 223 in which the elastic rubber 227 is set in the locking recess 225a so as to face each other, the locking piece 225d is elastically deformed with respect to the locking recess 225c. It is locked using. Thus, the divided

bodies

225A and 225B are joined and assembled together.

As shown in FIGS. 5 and 7, the side grip 211 is disposed on the outer surface of the outer rubber receiver 225, the band portion 213 wound around the outer surface of the outer rubber receiver 225, and disposed on the outer surface of the outer rubber receiver 225. A substantially U-shaped engaging surface 215a to be engaged with, a base portion 215, a grip portion 217 connected to the base portion 215 so as to be relatively rotatable about a long axis, and an operating rod with a tightening screw for tightening the band portion 213 219. The operation rod 219 passes through the center of the grip portion 217 and the base portion 215 in a loosely fitting manner, extends in the long axis direction, one end engages with the end portion of the band portion 213, and the other end grip portion 217. Is screwed into a nut 216 disposed inside the. The nut 216 is restricted from rotating relative to the grip portion 217. Accordingly, the grip portion 217 is rotated clockwise or counterclockwise around the major axis, and the operating rod 219 with a tightening screw screwed to the nut 216 is moved forward or backward in the major axis direction to thereby move the band portion 213. Tightening and releasing can be performed. The side grip 211 is fixed to the outer rubber receiver 225 by tightening the band portion 213.

According to the present embodiment, the side grip 211 is attached to the barrel portion 106 of the gear housing 107 via the vibration isolation mechanism 221. Therefore, during the machining operation by the hammer drill 101, vibration transmitted from the main body 103 to the side grip 211 is transmitted by elastic deformation of the plurality of elastic rubbers 227 in the vibration isolation mechanism 221. Can be reduced.

In the present embodiment, the spherical elastic rubber 227 is fitted into the engagement recess 223a of the inner rubber receiver 223 and the engagement recess 225a of the outer rubber receiver 225 disposed on the axis of the barrel portion 106, respectively. Thus, the structure is held in a sandwiched manner in the radial direction. With such a configuration, the elastic rubber 227 shears and deforms in the long axis direction of the hammer bit with respect to the vibration in the long axis direction of the hammer bit 119 generated during the machining operation. That is, according to the present embodiment, the vibration reduction effect of the side grip 211 can be improved by utilizing the characteristic of the elastic rubber 227 that the vibration reduction effect due to shear deformation is higher than the vibration reduction effect due to compression deformation. Is reasonable. Further, the elastic rubber 227 is configured to be arranged at equal intervals in the circumferential direction of the barrel portion 106. For this reason, it is possible to obtain a balanced vibration reducing action with respect to the barrel portion 106 around the major axis direction.

Further, in the present embodiment, the plurality of elastic rubbers 227 in the vibration isolation mechanism 221 are configured such that those adjacent to each other in advance by integral molding are connected to each other in an annular shape via a connection portion 227a. For this reason, the plurality of elastic rubbers 227 are made into one component, and the number of components can be reduced. Further, since the plurality of elastic rubbers 227 are made into one component, the elastic rubber 227 can be attached to be fitted (wrapped) to the outer peripheral surface of the inner rubber receiver 223, and the state can be maintained. For this reason, the inner rubber receiver 223 can be easily covered with the outer rubber receiver 225, whereby the assemblability of the vibration isolation mechanism 221 can be improved.

In the first and second embodiments, the case where the

elastic rubbers

173 and 227 are spherical has been described. However, a cylindrical shape may be used instead of the spherical shape.
Further, in the first embodiment, the outer rubber receiver 177 is provided in the lower connecting portion 155 and the inner rubber receiver 175 is provided in the cover member 104, but the inner rubber receiver 175 is provided in the lower connecting portion 155, An outer rubber receiver 177 may be provided on the cover member 104. In the first embodiment, the lower vibration isolation mechanism 171 may be applied to the upper vibration isolation mechanism 161.
In the first and second embodiments described above, a hammer drill has been described as an example of a striking tool. However, the hammer bit 119 may be applied to a hammer that performs only a striking operation in the long axis direction.

In view of the gist of the invention, the following aspects can be configured.
(Aspect 1)
The work tool according to any one of claims 1 to 5, wherein the vibration isolation mechanism includes an inner receiving portion (inner rubber receiver) and an annular outer portion arranged so as to surround the inner receiving portion. It is characterized by comprising a receiving part (outer rubber receiver) and the anti-vibration element arranged between the inner receiving part and the outer receiving part. "

(Aspect 2)
The work tool according to Aspect 1, wherein the vibration isolating element is formed in a spherical or cylindrical shape, and at least one of the inner receiving portion and the outer receiving portion has an outer surface of the vibration isolating element. It is characterized by having an engaging recess corresponding to the shape. "

(Aspect 3)
“The work tool according to claim 1 or 4, wherein the connection portion connecting the plurality of vibration isolation elements is formed in a cross-sectional shape smaller than the vibration isolation element.”

101 Hammer drill (blow tool)
103 Main body (tool body)
104 Cover member 104a Through hole 105 Motor housing 106 Barrel portion 106a Handle mounting portion 107 Gear housing 109 Hand grip (handle)
109a Trigger 111 Drive motor (motor)
113 motion conversion mechanism 115 impact element 117 power transmission mechanism 119 hammer bit (tip tool)
129 Piston 137 Tool holder 141 Cylinder 141a Air chamber 143 Strike 145 Impact bolt 151 Grip part 153 Upper connection part 155 Lower connection part 155a Columnar member 161 Upper vibration isolation mechanism 163 Compression coil spring 165 Dustproof cover 171 Lower vibration isolation Mechanism 173 Elastic rubber (anti-vibration element)
173a Connection part 175 Inner rubber support (inner support part)
175a Engaging recess 177 Outer rubber support (outer receiving part)
179 Stopper bolt 179a Head 181 Dust cover 211 Side grip (handle)
213 Band part 215 Base part 215a Engagement surface 216 Nut 217 Grip part 219 Operation rod 221 Anti-vibration mechanism 223 Inner rubber receiver (inner receiver)
223a Engaging recess 223b Protruding portion 225 Outer rubber receiver (outer receiving portion)
225a engaging recess 225b protrusion

225c locking recess

225d locking piece 225A split body 225B split body 227 elastic rubber (vibration isolation element)
227a connection part

Claims

A tool body in which a tip tool can be mounted in the tip region;
A handle connected to the tool body so as to be relatively movable;
An anti-vibration mechanism provided between the tool body and the handle;
A work tool having
The vibration isolation mechanism is
A plurality of vibration isolation elements spaced apart to reduce transmission of vibration between the tool body and the handle;
A connecting portion for connecting the plurality of vibration isolation elements to each other;
A work tool characterized by comprising:
The work tool according to claim 1,
All of the plurality of vibration isolating elements are formed in the same outer shape.
The work tool according to claim 1 or 2,
The work tool, wherein the plurality of vibration isolation elements are arranged at equal intervals around the long axis direction of the tool body.
The work tool according to any one of claims 1 to 3,
The work tool characterized in that the plurality of vibration isolation elements are connected in a ring shape by the connecting portion.
The work tool according to any one of claims 1 to 4,
The handle has a long grip portion extending in a direction intersecting with a major axis direction of the tool body,
The work tool, wherein the plurality of vibration isolation elements are arranged symmetrically with respect to the long axis of the grip portion.