JP2007160441A - Working tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for connecting a plurality of members only when the plurality of members are positioned in a predetermined proper relative position relationship in a working tool. <P>SOLUTION: This working tool 101 includes: a working tool body 103; a driving rotary member 164; a driven rotary member 165; and a locating member 191. The locating member 191 allows the driving rotary member 164 to be inserted and fitted to the working tool body 103 only when the driving rotary member 164 is placed in a preset predetermined relative position in the circumferential direction to the locating member 191, and allows the driven rotary member 165 to be inserted and fitted to the working tool body 103 only when the driven rotary member 165 is placed in a preset predetermined relative position in the circumferential direction to the locating member. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a work tool.

  German Patent No. 19716976 (Patent Document 1) discloses a hammer drill. In the hammer drill described in Patent Document 1, a clutch switching lever is disposed on the upper surface of the work tool main body. A crank mechanism and a clutch mechanism for striking a hammer bit as a tip tool are disposed in the internal space of the work tool main body. The switching operation of the switching lever by the user is transmitted as a vertical motion to the clutch switching member via a switching motion transmission member arranged in the internal space, and the clutch mechanism portion slides in the long axis direction (vertical direction) by this vertical motion. It is configured to be operated and switched to a power transmission state or a power cut-off state. In the configuration in which the switching lever is arranged on the upper surface of the work tool main body as in Patent Document 1, the switching operation of the switching lever is directly performed by the clutch mechanism because the switching lever and the clutch mechanism are placed in a mutually separated positional relationship. Difficult to communicate. Therefore, a single or a plurality of switching operation transmission members are interposed between the switching lever and the clutch mechanism.

As described above, in the configuration in which one or a plurality of switching operation transmission members are interposed between the switching lever and the clutch mechanism, the switching lever and the switching operation are accurately transmitted to the clutch mechanism. The relative positional relationship with the transmission member, and when there are a plurality of switching operation transmission members, they may be connected in a positioned state so that the relative positional relationship between the intermediate members is appropriate. I need it. If they are not connected in an appropriate relative positional relationship, the switching operation amount of the switching lever is not accurately transmitted to the clutch mechanism unit, and the clutch mechanism unit may malfunction.
German Patent No. 19716976

  In view of such points, the present invention provides a technique that enables a plurality of members to be connected to each other only when the plurality of members are positioned in a proper relative positional relationship determined in advance. Objective.

In order to achieve the above object, the invention described in each claim is configured.
According to the first aspect of the present invention, the drive side has a work tool main body and a drive shaft, and rotates around the drive shaft in a state of being inserted and attached to the work tool main body in the direction of the drive shaft. A work tool having a rotating member, a driven shaft, and a driven-side rotating member that rotates around the driven shaft while being inserted and attached to the working tool body in the direction of the driven shaft is configured. The drive-side rotating member and the driven-side rotating member are connected to each other in a state where the drive shaft and the driven shaft intersect each other, whereby the rotational force around the drive shaft of the drive-side rotating member is transmitted to the drive-side rotating member. A predetermined machining operation is performed by transmitting to a driven side rotating member arranged in an intersecting manner. The “predetermined machining operation” in the present invention is a mode in which the tip tool of the work tool is driven via the rotational force of the driving side rotating member and the driven side rotating member, and the tip tool performs the machining operation, or the driving side. It suitably includes an operation for switching the driving state of the tip tool via the rotational force of the rotating member and the driven-side rotating member, for example, a switching operation for switching the driving state of the tip tool between rotation driving and linear driving. The present invention typically includes a hammer in which a hammer bit performs a striking operation in the long axis direction, or an impact-type work tool such as a hammer drill in which the hammer bit performs a striking operation in the long axis direction and a rotation operation around the long axis direction. However, the present invention is not limited to an impact-type work tool, but a work tool that performs a machining work by driving the tip tool linearly in the long axis direction, or the tip tool rotates around the long axis direction. Therefore, the present invention may be applied to a work tool that performs a machining operation, or a work tool that performs a predetermined machining operation by performing a combined operation of a linear operation and a rotation operation.

As a characteristic configuration, the work tool of the present invention further includes a single positioning member that determines the arrangement positions of the rotating members in the work tool. In addition, the positioning member is connected to the working tool only when the driving side rotating member and the positioning member are placed at a predetermined relative position set in advance in the circumferential direction of the driving shaft. Insertion into the main body of the work tool is allowed when the positioning member interferes with the driving side rotating member when it is placed in a position other than the relative position. It is set to prohibit installation. Furthermore, the positioning member is placed at a predetermined relative position set in advance in the circumferential direction of the driven shaft, with respect to the driven side rotating member arranged in a crossing manner with the driving side rotating member. Only when the driven rotating member is inserted and attached to the work tool main body, and the positioning member interferes with the driven rotating member when placed at a position other than the relative position. It is set to prohibit insertion and attachment of the driven-side rotating member to the work tool main body.
As described above, in the present invention, when the drive side rotating member is attached to the work tool main body by being inserted in the drive axis direction, the driven side rotary member is attached to the work tool main body by being inserted in the driven axis direction. In this case, the rotation member is allowed to be inserted into the work tool main body only when each of the rotating members is placed at a predetermined relative position in the circumferential direction with respect to the positioning member. By adopting such a configuration, according to the present invention, the driving-side rotating member and the driven-side rotating member can be reliably connected to a predetermined predetermined positional relationship, and mounting workability is improved. . In addition, it is possible to omit a wasteful work such as a rework work when the driving side rotating member and the driven side rotating member are connected in an incorrect positional relationship.

(Invention of Claim 2)
According to the second aspect of the present invention, the driven-side rotating member in the work tool according to the first aspect operates the mode switching member of the machining operation by the work tool by rotating around the driven shaft. Configured as follows. Further, the driven side rotating member has an eccentric pin extending in the direction of the driven shaft at a position eccentric from the driven shaft, and when the driven side rotating member is rotationally driven by the driving side rotating member, the eccentric pin is It is configured to rotate eccentrically around the driven shaft and to operate the mode switching member of the machining operation via an operation component in a direction intersecting the driven axis among the eccentric rotation operations. The “mode switching member” in the present invention is typically provided in a drive system that drives the tip tool, and interrupts the transmission of the rotational force and the power transmission state in which the rotational force on the driving side is transmitted to the driven side. The clutch member that can be switched between the power cut-off state corresponds to this. For example, in a hammer drill configured such that a hammer bit as a tip tool performs a striking operation in the long axis direction and a rotating operation around the long axis direction, the clutch member provided in the drive system of the hammer bit is in a power transmission state. By switching between the power-off state and the power-off state, the hammer bit driving mode is switched to the hammering mode only by the hammering operation, the drilling mode only by the rotation operation, or the hammer drilling operation by the hammering operation and the rotation operation. It is possible. The present invention is suitably used for a work tool having such an “aspect switching member”. In this case, the driving side rotating member and the driven side rotating member constitute a switching operation transmitting unit that transmits a switching operation of the switching unit that is switched by the user.
In the present invention, the driven-side rotating member has an eccentric pin, and the mode switching member is operated via an operation component in a direction intersecting the driven axis of the rotating operation of the eccentric pin. For this reason, it is possible to appropriately determine the relative position of the eccentric pin with respect to the mode switching member by connecting the driving side rotating member and the driven side rotating member with a predetermined relative positional relationship set in advance. The switching member can be operated with a regular stroke.

(Invention of Claim 3)
According to a third aspect of the present invention, in the work tool according to the first or second aspect, the positioning member has the positioning pin member, and each relative position of the positioning member with respect to the driving side rotating member and the driven side rotating member is The long pin end portion and the outer peripheral portion of the positioning pin member are set. According to such a configuration, the driving side rotating member and the driven side rotating member arranged in a crossing manner can be rationally connected to a predetermined relative position using a single positioning member.

  According to the present invention, a technique is provided that enables a plurality of members to be connected to each other only when the plurality of members are positioned in a predetermined relative positional relationship in the work tool.

  Hereinafter, embodiments of the present invention will be described in detail 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 side 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 not shown for convenience in the main body portion 103 that forms the outline of the hammer drill 101 and the tip region (left side in the drawing) of the main body portion 103. A hammer bit 119 as a tip tool detachably attached via a hollow tool holder, and a hand grip 109 gripped by a user connected to the opposite side of the hammer bit 119 of the main body 103 are mainly constituted. ing. The hammer bit 119 is held by a tool holder in a state in which relative linear movement in the major axis direction is possible and relative rotation in the circumferential direction is restricted. The main body 103 corresponds to the “work tool main body” in the present invention. 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 includes a motor housing 105 that houses the drive motor 111, and a gear housing 107 that houses the motion conversion mechanism 113, the striking element 115, and the power transmission mechanism 117. 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 rotation output of the drive motor 111 is transmitted to the hammer bit 119 after being appropriately decelerated by the power transmission mechanism 117, and the hammer bit 119 is rotated in the circumferential direction. The drive motor 111 is energized and driven by a pulling operation of a trigger 109 a disposed on the hand grip 109.

  FIG. 2 is a sectional view showing an enlarged state of the main part of the hammer drill 101. The motion conversion mechanism 113 is mainly composed of a drive gear 121, a driven gear 123, a crankshaft 122, a crank plate 125, a crank arm 127, and a piston 129 as a driver, which are driven to rotate in a horizontal plane by a drive motor 111. The crank shaft 114, the crank plate 125, the crank arm 127, and the piston 129 constitute a crank mechanism 114. The piston 129 is slidably disposed in the cylinder 141 and performs a linear motion along the cylinder 141 as the drive motor 111 is driven to energize.

  The crankshaft 122 is disposed so that the major axis direction of the crankshaft 122 is a vertical direction (vertical direction) intersecting the major axis direction of the hammer bit 119, and a clutch is interposed between the crankshaft 122 and the driven gear 123. A member 124 is disposed. The clutch member 124 corresponds to the “mode switching member” in the present invention. The clutch member 124 is formed in a cylindrical shape having an overhanging flange portion 124b at one end (upper end) in the long axis direction, and is relatively movable in the long axis direction on the crankshaft 122, and in the circumferential direction. It is attached to rotate integrally, and has clutch teeth 124a on the outer periphery. On the other hand, the driven gear 123 is provided with a circular recess, and clutch teeth 123a are formed on the inner periphery of the circular recess. The clutch member 124 is configured such that the clutch tooth 124a of the clutch member 124 meshes with the clutch tooth 123a of the driven gear 123 or the meshing engagement is released by moving in the major axis direction on the crankshaft 122. It is said. That is, the clutch member 124 is between a power transmission state in which the driving force of the driven gear 123 is transmitted to the crankshaft 122 (see FIG. 2) and a power interruption state in which the transmission of the driving force is interrupted (illustration is omitted for convenience). The clutch teeth 124a are normally urged by the urging spring 126 in a direction in which the clutch teeth 124a are engaged with and engaged with the clutch teeth 123a of the driven gear 123. Switching of the operating state of the clutch member 124 is performed by a mode switching mechanism 153 described later.

  As shown by a broken line in FIG. 1, the striking element 115 is striker 143 as a striking element slidably disposed on the bore inner wall of the cylinder 141, and is slidably disposed on the tool holder. An impact bolt 145 as a meson that transmits kinetic energy to the hammer bit 119 is mainly configured. The striker 143 is driven via an air spring in the air chamber 141a of the cylinder 141 in accordance with the sliding motion of the piston 129, and collides with (impacts) an impact bolt 145 that is slidably disposed on the tool holder. The striking force is transmitted to the hammer bit 119 via 145.

  The power transmission mechanism 117 meshes with the intermediate gear 132 that meshes with and engages with the drive gear 121, the intermediate shaft 133 that rotates with the intermediate gear 132, the small bevel gear 134 that is rotationally driven in the horizontal plane with the intermediate shaft 133, and the small bevel gear 134. A large bevel gear 135 that engages and rotates in a vertical plane and a slide sleeve 147 that meshes with and engages with the large bevel gear 135 and is driven to rotate are mainly configured. The rotational driving force of the slide sleeve 147 is transmitted to the tool holder via the cylinder 141 that rotates together with the slide sleeve 147, and further transmitted to the hammer bit 119 held by the tool holder.

  The slide sleeve 147 constitutes a clutch mechanism in the power transmission mechanism 117, and can be relatively moved on the cylinder 141 in the long axis direction of the hammer bit, and is configured to rotate integrally in the circumferential direction. Yes. The slide sleeve 147 has a clutch tooth 147a on the outer periphery of one end in the long axis direction, and meshes with the clutch tooth 135a formed on the large bevel gear 135 when moving relative to the cylinder 141 rearward (hand grip side). When engaged and relatively moved forward (hammer bit side), the meshing engagement is released. That is, the slide sleeve 147 is between a power transmission state (not shown for convenience) that transmits the rotational driving force of the large bevel gear 135 to the cylinder 141 and a power cutoff state that blocks transmission of the driving force (see FIG. 2). Can be switched.

  Next, the mode switching mechanism 153 that switches the driving mode of the hammer bit 119 will be described with reference to FIG. The mode switching mechanism 153 includes a hammer mode in which the hammer bit 119 performs only a striking operation, a hammer drill mode in which the hammer bit 119 performs a striking operation and a rotation operation, and a drill mode in which the hammer bit 119 performs only a rotation operation. It is possible to switch between them. The mode switching mechanism 153 switches the mode switching member 155, the first switching mechanism 157 that switches the clutch member 124 of the crank mechanism 114 based on the switching operation of the mode switching member 155, and the slide sleeve 147 of the power transmission mechanism 117. The second switching mechanism 159 is mainly configured. The mode switching member 155 is disposed outside the upper surface of the gear housing 107 (upper side in FIG. 1). The mode switching member 155 is attached to the gear housing 107 so as to be rotatable in a horizontal plane, and the driving mode is switched by being rotated by a user.

  When the mode switching member 155 is rotated for mode switching, the first switching mechanism 157 rotates the first eccentric pin 167 around the rotation axis of the rotating member 166 (eccentric rotation) so that the clutch of the crank mechanism 114 The member 124 is configured to be switched. The first switching mechanism 157 mainly includes a first gear 161, a second gear 162, a rotation transmission shaft 163, a third gear 164, a fourth gear 165, a rotating member 166, and a first eccentric pin 167.

  The first gear 161 is provided to rotate in the horizontal plane together with the mode switching member 155 when the mode switching member 155 is rotated in the horizontal plane. The second gear 162 meshes with and engages with the first gear 161 and is integrally formed with one end (upper end) in the long axis direction of the rotation transmission shaft 163. The rotation transmission shaft 163 is arranged so that the major axis direction thereof is parallel to the major axis direction of the crankshaft 122, that is, the vertical direction. A third gear 164 is formed integrally with the other end (lower end) in the long axis direction of the rotation transmission shaft 163, and the third gear 164 is formed integrally with the rotating member 166. The gear 165 is meshed and engaged. The rotation member 166 is disposed on the lower side of the rotation transmission shaft 163 so that the major axis direction thereof is orthogonal to the rotation transmission shaft 163, that is, the horizontal direction. The third gear 164 and the fourth gear 165 are each constituted by a bevel gear, and are engaged with each other.

  Therefore, when the mode switching member 155 is switched, the rotation transmission shaft 163 is rotated in the horizontal plane via the first gear 161 and the second gear 162, and the rotation operation of the rotation transmission shaft 163 is further increased. The rotation is transmitted to the rotating member 166 through the third gear 164 and the fourth gear 165 as a rotating motion in the vertical plane. The first eccentric pin 167 is provided on the axial end surface of the rotating member 166 at a position eccentric from the rotating axis of the rotating member 166 by a predetermined amount, and is disposed so as to face the lower surface of the flange portion 124 b of the clutch member 124. Yes. Therefore, the first eccentric pin 167 has an up-down direction component (long-axis direction component of the crankshaft 122) when the rotating member 166 is rotated in the vertical plane and eccentrically rotates around the rotation axis of the rotating member 166. The clutch member 124 is moved up and down along the crankshaft 122 while being engaged with the flange portion 124b of the clutch member 124, thereby switching the clutch member 124 between the power transmission state and the power cut-off position. Operate. The first gear 161, the second gear 162, the rotation transmission shaft 163, the third gear 164, and the fourth gear 165 constitute a switching operation transmission mechanism.

  When the mode switching member 155 is switched to the hammer mode or the hammer drill mode, the first eccentric pin 167 moves to the same position as the rotation axis of the rotating member 166 or to a lower position in the vertical direction as shown in FIG. Is done. At this time, the clutch member 124 is moved downward by the biasing spring 126, and the clutch teeth 124 a are engaged with the clutch teeth 123 a of the driven gear 123. That is, the clutch member 124 is switched to the power transmission state. On the other hand, when the mode switching member 155 is switched to the drill mode, the first eccentric pin 167 is moved to a position above the rotation axis of the rotating member 166 in the vertical direction. At this time, the clutch member 124 is moved upward against the biasing force of the biasing spring 126 by the first eccentric pin 167, and the meshing engagement of the clutch teeth 124a and 123a is released. That is, the clutch member 124 is switched to the power cut-off state.

  The second switching mechanism 159 is configured to move the slide sleeve 147 constituting the clutch mechanism of the power transmission mechanism 117 in the major axis direction of the cylinder 141 when the mode switching member 155 is operated for mode switching. That is, when the mode switching member 155 is switched to the hammer drill mode or the drill mode, the clutch teeth 147a of the slide sleeve 147 are engaged with and engaged with the clutch teeth 135a of the large bevel gear 135, while the mode is switched to the mode. When the switching member 155 is switched to the hammer mode, the clutch teeth 147a and 135a are disengaged from each other to be switched to the power cut-off state. The slide sleeve 147 is normally biased by a biasing spring 148 in a direction in which the clutch teeth 147a meshes with and engages with the clutch teeth 135a of the large bevel gear 135. The specific configuration of the second switching mechanism 159 itself is not directly related to the present invention, and thus detailed description thereof is omitted.

  According to the hammer drill configured as described above, when the mode switching member 155 is switched to the hammer mode, the clutch member 124 is switched to the power transmission state via the first switching mechanism 157, and at the same time, the second switching mechanism. Through 159, the slide sleeve 147 is switched to the power cut-off state. Accordingly, if the drive motor 111 is energized and driven in this state, a striking force is applied to the hammer bit 119 via the crank mechanism 114 and the striking element 115. That is, in the hammer mode, a predetermined hammer operation is performed only by the hammering operation (hammer operation) of the hammer bit 115.

  When the mode switching member 155 is switched to the hammer drill mode, the clutch member 124 is switched to the power transmission state via the first switching mechanism 157, and at the same time, the slide sleeve 147 is switched to the power transmission state via the second switching mechanism 159. Can be switched. Therefore, at this time, if the drive motor 111 is energized and driven, a hammering force is applied to the hammer bit 119 via the crank mechanism 114 and the hammering element 115, and the hammer bit 119 is rotationally driven via the power transmission mechanism 117. The For this reason, in the hammer drill mode, the hammer bit 119 performs a predetermined hammer drill operation by a combined operation of a hammering operation (hammer operation) and a rotation operation (drilling operation).

  When the mode cutting member 155 is switched to the drill mode, the clutch member 124 is switched to the power cut-off state via the first switching mechanism 157, and at the same time, the slide sleeve 147 is switched to the power transmission state via the second switching mechanism 159. Can be switched to. Therefore, at this time, if the drive motor 111 is energized, the hammer bit 119 is rotationally driven via the power transmission mechanism 117. For this reason, in the drill mode, a predetermined drill operation is performed only by the rotation operation (drill operation) of the hammer bit 119.

Next, the mounting structure and mounting method of the first switching mechanism 157 that switches the clutch member 124 of the crank mechanism 114 in the mode switching mechanism 153 will be described with reference to FIGS. 3 is an explanatory view for explaining a mounting structure and a mounting method of the first switching mechanism 157 with respect to the gear housing 107, FIG. 4 is a view taken along arrow A in FIG. 3, and FIG. 5 is a cross-sectional view taken along line BB in FIG. FIG. 6 is a view taken in the direction of arrow C in FIG.
As described above, the first switching mechanism 157 in the present embodiment includes the first gear 161 integrated with the mode switching member 155, the second gear 162 meshingly engaged with the first gear 161, and the second gear. Rotation transmission shaft 163 having 162 integrally, third gear 164 provided integrally with rotation transmission shaft 163, fourth gear 165 meshingly engaged with third gear 164, and fourth gear 165 are integrated. And a first eccentric pin 167 provided integrally with the rotating member 166. According to the above configuration, the relative positional relationship between the switching operation position of the mode switching member 155 and the operation position of the first eccentric pin 167 when the mode switching member 155 is rotated to switch the mode is extremely important. . In other words, if there is a “displacement” in the positional relationship, when the mode switching member 155 is switched, the operation amount of the clutch member 124 operated by the first eccentric pin 167 does not become a preset set value but operates. It may cause defects. In order to avoid such malfunction, when the above-described members constituting the first switching mechanism 157 are attached to the gear housing 107, the meshing engagement between the first gear 161 and the second gear 162 and the third It is necessary that the meshing engagement between the gear 164 and the fourth gear 165 is performed in an appropriate positional relationship predetermined in the circumferential direction (rotational operation direction).

  In the present embodiment, the constituent members of the first switching mechanism 157 include a rotating member 166 having a first eccentric pin 167 and a fourth gear 165, a rotation transmission shaft 163 having a third gear 164 and a second gear 162, and a first member. The mode switching member 155 having one gear 161 is configured to be inserted by being inserted into the mounting holes 107c to 107e (see FIG. 2) of the gear housing 107 in this order. The insertion order is indicated by numbers and arrows in FIG. Then, at the time of attachment by this insertion, the fourth gear 165 of the rotation member 166 and the third gear 164 of the rotation transmission shaft 163, and the second gear 162 of the rotation transmission shaft 163 and the first gear 161 of the mode switching member 155 are connected. Positioning means for determining the circumferential position at the time of insertion is provided so that they are engaged and engaged with each other in an appropriate positional relationship in the circumferential direction (rotation direction).

  Positioning means related to the fourth gear 165 of the rotating member 166 and the third gear 164 of the rotation transmission shaft 163 is configured by positioning pins 191 provided on the gear housing 107. The third gear 164 corresponds to the “driving side rotating member” in the present invention, the fourth gear 165 corresponds to the “driven side rotating member” in the present invention, and the positioning pin 191 is the “positioning member” in the present invention. Corresponding to The positioning pin 191 has a shaft portion 192 and a flange portion 193, and is attached to the gear housing 107 so that its axial direction is parallel to the axial direction (front-rear direction) of the rotating member 166, as shown in FIG. ing. The positioning pin 191 attached to the gear housing 107 is configured such that the flange portion 193 is exposed to the outside of the gear housing 107 and the tip portion of the shaft portion 192 protrudes into the gear housing 107 by a predetermined length. ing.

  The rotating member 166 includes a disk 194 fixed by a screw 195 on the opposite side of the fourth gear 165 in the axial direction. The rotating member 166 corresponds to the “driven shaft” in the present invention. The disc 194 is set to have a diameter slightly larger than the outer diameter of the fourth gear 165, and on the outer periphery, the circular arc-shaped concave portion 194a corresponding to the arc shape of the outer peripheral edge of the flange portion 193 of the positioning pin 191 (FIG. See). The gear housing 107 is formed with a circular mounting hole 107c (see FIG. 2) penetrating in the front-rear direction (a direction intersecting the long axis direction of the crankshaft 122) for mounting the rotating member 166. The rotating member 166 is attached to the gear housing 107 by being inserted into the attachment hole 107c from the rear. In this insertion attachment, when the disk 194 of the rotating member 166 is placed at a position (see FIGS. 3 and 4) where the concave portion 194 a of the disk 194 corresponds to the outer peripheral edge of the flange portion 193 of the positioning pin 191. That is, when it is placed at a position where the arc surface of the recess 194a and the outer peripheral edge of the flange portion 193 coincide with each other, it can pass without interfering with the flange portion 193, and when it is placed at a non-corresponding position, It is configured such that further insertion is prohibited due to interference. That is, the rotating member 166 having the fourth gear 165 can be attached to the gear housing 107 only when it is inserted into the attachment hole 107c while being properly positioned at a predetermined relative position in the circumferential direction with respect to the positioning pin 191. It is an acceptable configuration. The rotating member 166 attached to the gear housing 107 is rotatably supported by the inner wall surface of the attaching hole 107c at a position where the disc 194 passes through the flange portion 193 of the positioning pin 191. In this state, the first eccentric pin 167 is inserted into the gear housing 107 and disposed opposite to the flange portion 124b of the clutch member 124.

  As shown in FIGS. 2 and 3, the rotating member 166 and the disc 194 are fitted with a shaft portion 166a formed on one end side in the axial direction of the rotating member 166 and a shaft hole 194b formed in the disc 194. In the joined state, it is fastened by a screw 195. The shaft portion 166a and the shaft hole 194b are each formed in a circular cross section having notched flat portions 166b and 194c in a part in the circumferential direction, and are fitted in a state of being positioned via the respective flat portions 166b and 194c. It is set as the structure. That is, the rotating member 166 and the disc 194 can be fixed by the screw 195 only when the shaft portion 166a and the shaft hole 194b are placed at a predetermined relative position. As a result, in a state where the screw 195 is fastened, the first eccentric pin 167 of the rotating member 166 and the positioning recess 194a of the disk 194 are assembled in a predetermined predetermined positional relationship.

  The rotation transmission shaft 163 has a flange portion 163b having a diameter larger than that of the third gear 164 between the shaft portion 163a and the third gear 164. The shaft end of the positioning pin 191 is disposed on the outer periphery of the flange portion 163b. A substantially rectangular recess 163c (see FIG. 5) having a width corresponding to the outer diameter of the portion 192a is formed. The rotation transmission shaft 163 corresponds to the “drive shaft” in the present invention. The gear housing 107 is formed with a circular attachment hole 107d (see FIG. 2) penetrating in the vertical direction (long axis direction of the crankshaft 122) to attach the rotation transmission shaft 163. The rotation transmission shaft 163 is attached to the gear housing 107 by being inserted into the vertical attachment hole 107d from above. At the time of this insertion attachment, the flange portion 163b of the rotation transmission shaft 163 is positioned when the concave portion 163c of the flange portion 163b is placed at a position corresponding to the shaft end portion 192a of the positioning pin 191 (see FIGS. 3 and 5). When the concave portion 163c is placed at a position that coincides with the shaft end portion 192a in the circumferential direction, it can pass without interfering with the shaft end portion 192a, and when placed at a non-corresponding position, it interferes with the shaft end portion 192a. Thus, further insertion is prohibited. That is, the rotation transmission shaft 163 having the third gear 164 is attached to the gear housing 107 only when it is inserted into the attachment hole 107d while being properly positioned at a predetermined relative position in the circumferential direction with respect to the positioning pin 191. Is allowed. The rotation transmission shaft 163 attached to the gear housing 107 is rotatably supported by the inner wall surface of the attachment hole 107d at a position where the flange portion 163b passes the shaft end portion 192a of the positioning pin 191.

  As described above, the rotation member 166 and the rotation transmission shaft 163 are attached to the gear housing 107 in a state in which the major axis directions intersect each other. When the rotation member 166 and the rotation transmission shaft 163 are attached to the gear housing 107, the fourth gear (bevel gear) 165 of the rotation member 166 and the third gear (bevel gear) 164 of the rotation transmission shaft 163 are predetermined with each other. Thus, they are engaged and engaged with each other in an appropriate relative positional relationship.

  Next, positioning means related to the second gear 162 of the rotation transmission shaft 163 and the first gear 161 of the mode switching member 155 will be described. As shown in FIG. 2, the mode switching member 155 is a mode switching assembly in which the mode switching member 155, the first gear 161, and the cover member 196 are coupled to each other by a screw 197. Attachment to the housing 107 is performed by fitting the mode switching assembly into the attachment hole 107e on the upper surface of the gear housing 107 from above. That is, this attachment is performed in such a manner that the mode switching assembly is inserted into the attachment hole 107e while the teeth of the first gear 161 are engaged with the teeth of the second gear 162 and slid in the gear thickness direction (long axis direction). It will be.

  As shown in FIG. 3, the positioning means related to the second gear 162 and the first gear 161 is constituted by a positioning wall member 199 formed on the first gear 161. The positioning wall member 199 is formed on the lower end surface (lower side surface) in the axial direction of the first gear 161 so as to cover one end in the tooth thickness direction of the tooth portion 161a. That is, it has an outer diameter substantially equal to the gear diameter of the first gear 161, and an opening 199a is formed in a predetermined region in the circumferential direction of the positioning wall member 199. When the mode switching assembly is attached to the gear housing 107, the positioning wall member 199 is placed at a position (see FIGS. 3 and 6) in which the opening 199a corresponds (matches) with the tooth portion 162a of the second gear 162. Sometimes, it can pass without interfering with the tooth portion 162a of the second gear 162, and when placed in a non-corresponding position, it is interfered with the tooth portion 162a of the second gear 162 and insertion is prohibited. That is, the mode switching member 155 having the first gear 161 is attached to the gear housing 107 only when the first gear 161 is properly positioned at a predetermined relative position in the circumferential direction with respect to the second gear 162. Accordingly, the first gear 161 and the second gear 162 are meshed and engaged with each other in an appropriate relative positional relationship determined in advance. From the above, according to the present embodiment, the mode switching member 155 and the first eccentric pin 167 are assembled in a predetermined positional relationship with necessity.

  As described above, according to the present embodiment, when the rotation transmission shaft 163 having the third gear 164 and the rotation member 166 having the fourth gear 165 are inserted into the gear housing 107 and attached, the positioning pin 191 is used. The attachment is possible only at a prescribed relative position defined, and when the mode switching member 155 having the first gear 161 is attached to the gear housing 107, the attachment is performed at a prescribed relative position defined by the positioning wall member 199. Only the attachment is possible. Accordingly, the third gear 164 and the fourth gear 165, and the first gear 161 and the second gear 162 can be reliably engaged and engaged with each other in a predetermined regular positional relationship. That is, it is possible to reliably prevent meshing engagement with an incorrect relative positional relationship. In addition, according to the present embodiment, it is possible to omit a useless work such as re-installation work in the case of meshing engagement with an incorrect positional relationship.

  Moreover, according to this Embodiment, it was set as the structure which sets the positioning of the 3rd gear 164 and the 4th gear 165 using the long-axis end part of the axial part 192 of the positioning pin 191, and the outer peripheral part of the flange part 193. Thus, the third gear 164 and the fourth gear 165 arranged so as to cross each other can be reasonably meshed and engaged at a predetermined relative position using the single positioning pin 191.

  In the present embodiment, for positioning the positioning pin 191 and the fourth gear 165, the positioning recess 194a is provided on the disk 194 side of the rotating member 166, but a recess is provided on the positioning pin 191 side. The positioning recess 163c is provided in the flange portion 163b of the rotation transmission shaft 163 for positioning the positioning pin 191 and the third gear 164. However, a recess is provided on the positioning pin 191 side. You can change it.

In view of the gist of the above invention, the following modes are conceivable regarding the configuration of the driving side rotating member or the driven side rotating member.
"One or both of the driving side rotating member and the driven side rotating member have a plurality of members that can be engaged with each other, and the plurality of members are placed at predetermined predetermined relative positions. It is allowed to engage only when it is engaged, and the engagement is prohibited when it is placed at a position other than the relative position "or" the driven-side rotating members are mutually in the driven shaft direction. A plurality of members that are fastened in a fitted state, and the plurality of members are fitted together only when placed in a predetermined relative position in a circumferential direction around the driven shaft direction. It is set to be prohibited from fitting when placed in a position other than the relative position. "
It is an aspect.
Note that typically, the “plurality of members” corresponds to the rotating member 166 and the disk 194 in the embodiment. According to the above aspect, the plurality of members can be properly fixed at predetermined relative positions.

It is a sectional side view showing the whole hammer drill composition concerning a 1st embodiment of the present invention. It is a sectional side view which shows the principal part of a hammer drill. It is explanatory drawing explaining the attachment structure with respect to the gear housing of a 1st switching mechanism, and the attachment method. It is A arrow directional view in FIG. FIG. 4 is a sectional view taken along line BB in FIG. 3. It is C arrow line view in FIG.

Explanation of symbols

101 Hammer drill (work tool)
103 Main body (work tool main body)
105 Motor housing 107 Gear housing 107c to 107e Mounting hole 109 Hand grip 109a Trigger 111 Drive motor 113 Motion conversion mechanism 114 Crank mechanism 115 Stroke element 117 Power transmission mechanism 119 Hammer bit 121 Drive gear 122 Crank shaft 123 Driven gear 123a Clutch tooth 124 Clutch Member 124a Clutch tooth 124b Flange portion 125 Crank plate 126 Energizing spring 127 Crank arm 129 Piston 132 Intermediate gear 133 Intermediate shaft 134 Small bevel gear 135 Large bevel gear 135a Clutch tooth 141 Cylinder 141a Air chamber 143 Striker 145 Impact bolt 147 Slide sleeve 147a Clutch tooth 148 Biasing spring 153 Mode switching mechanism 155 Mode switching member 157 First switching mechanism 1 59 Second switching mechanism 161 First gear 162 Second gear 163 Rotation transmission shaft 164 Third gear 165 Fourth gear 166 Rotating member 167 First eccentric pin 191 Positioning pin 192 Shaft 192a Shaft end 193 Flange 194 Disk 194a Positioning recess 195 Screw 196 Cover member 197 Screw 199 Positioning wall member 199a Opening

Claims (3)

A work tool body;
A drive-side rotating member that has a drive shaft and rotates around the drive shaft in a state of being inserted and attached to the work tool body in the drive shaft direction;
A driven-side rotating member that rotates around the driven shaft in a state where the driven shaft is inserted and attached to the work tool main body, and has a driven shaft;
The driving-side rotating member and the driven-side rotating member are connected to each other in a state where the driving shaft and the driven shaft intersect each other, and thereby the rotational force around the driving shaft of the driving-side rotating member is applied to the driving side. A work tool configured to perform a predetermined machining operation by transmitting to the driven side rotation member arranged in a crossing manner with the rotation member,
Furthermore, it has a single positioning member that determines each arrangement position of the rotating members in the work tool,
The positioning member rotates with respect to the driving side rotating member only when the driving side rotating member and the positioning member are placed at a predetermined relative position set in advance in the circumferential direction of the driving shaft. When the member is inserted into and attached to the work tool main body and is placed at a position other than the relative position, the positioning member interferes with the driving side rotating member, so that the driving side rotating member Is set to prohibit insertion and attachment to the work tool body,
Further, the positioning member has a predetermined rotation preset with respect to the circumferential direction of the driven shaft with respect to the driven side rotating member arranged in a crossing manner with the driving side rotating member. Only when it is placed at a relative position, the driven-side rotating member is allowed to be inserted and attached to the work tool body, and when placed at a position other than the relative position, the positioning member is A work tool configured to prohibit insertion and attachment of the driven side rotating member to the work tool body by interfering with the driven side rotating member. The work tool according to claim 1,
The driven side rotating member is configured to operate the mode switching member of the machining operation by the work tool by rotating around the driven shaft,
The driven-side rotating member has an eccentric pin extending in the direction of the driven shaft at a position eccentric from the driven shaft, and when the driven-side rotating member is rotationally driven by the drive-side rotating member, An eccentric pin rotates eccentrically around the driven shaft, and is configured to operate the mode switching member of the machining operation via an operation component in a direction intersecting the driven axis of the eccentric rotation operation. A featured work tool. The work tool according to claim 1 or 2,
The positioning member has a positioning pin member,
Each working position of the positioning member with respect to the driving side rotating member and the driven side rotating member is set using a long axis end portion and an outer peripheral portion of the positioning pin member.

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