Work machine

Abstract

To improve convenience.SOLUTION: In a telescopic pipe 50 of a chainsaw 10, an inner pipe 92 is provided inside an outer pipe unit 60. In the shortest state of the telescopic pipe 50, movement of a tip pipe 82 to a rear side is restricted by the inner pipe 92. Specifically, the inner pipe 92 indirectly abuts against the tip pipe 82 via a cap 84 to restrict the movement of the tip pipe 82 to the rear side. When viewed in the front-rear direction, the tip pipe 82 and the inner pipe 92 are similar in sectional shape. Thus, a collision load generated by the abutment of the tip pipe 82 moving rearward against the inner pipe 92 can be received over the entire section of the inner pipe 92. Thus, destruction of the inner pipe 92 can be suppressed more than a configuration where a local collision load is input to the inner pipe 92. Thus, as replacement or the like caused by the destruction of the inner pipe 92 is made unnecessary, convenience for a user can be improved.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a work machine. [Background technology]

[0002] The power tool (working machine) described in Patent Document 1 below includes a grip part having a power supply part, a telescopic rod part extending forward from the grip part, and a drive part provided at the tip of the rod part. The rod part has an outer pipe and a tip pipe, and the tip pipe is connected to the outer pipe so as to be movable relative to it in the front-to-rear direction. This allows the relative position of the grip part and the drive part to be changed by extending or retracting the rod part depending on the work style. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2017 / 014008 Summary of the Invention [Problem to be solved by the invention]

[0004] When the power tool is in the shortest position, the pivoting portion provided in the middle of the tip pipe abuts against the connecting portion provided at the tip of the outer pipe, restricting movement of the tip pipe toward the base end.

[0005] However, some power tools do not have the above-mentioned rotating part. In such cases, for example, a boss can be provided on the grip part that secures the outer pipe, and the tip pipe can be brought into contact with the boss to restrict movement of the tip pipe toward the base end. In other words, the boss on the grip part functions as a stopper. However, when the power tool is brought to its shortest position, the tip pipe moving rearward collides with the boss, which applies a localized collision load to the boss and may damage it. If the boss is damaged, the grip part must be replaced, which may reduce convenience for the operator.

[0006] SUMMARY OF THE INVENTION In consideration of the above, an object of the present invention is to provide a work machine that can improve convenience. [Means for solving the problem]

[0007] One or more embodiments of the present invention are a work machine comprising: a drive unit; a main body unit having an operating unit that is actuated by the drive force of the drive unit; a grip unit to be gripped by an operator; and an extension mechanism that extends in a predetermined direction, with the grip unit provided at a base end and the main body unit provided at a tip end, and is configured to be extendable and retractable in the predetermined direction, wherein the extension mechanism includes: an outer tube including a first tubular member to which a first case unit that constitutes either the grip unit or the main body unit is fixed; a second tubular member that is inserted inside the outer tube so as to be movable relative to the outer tube, and to which a second case unit that constitutes the other of the grip unit or the main body unit is fixed; and a third tubular member that is provided inside the outer tube and restricts movement of the second tubular member toward the base end when the extension mechanism is in the shortest position, wherein the second tubular member and the third tubular member have the same cross-sectional shape when viewed from the predetermined direction.

[0008] One or more embodiments of the present invention are directed to a work machine in which, when the telescopic mechanism is in the shortest position, the second case portion is disposed away from the outer cylinder toward the tip end.

[0009] In one or more embodiments of the present invention, the outer cylinder has a locking mechanism provided at the tip of the first tubular member, and the locking mechanism is configured to be switchable between an unlocked state that allows relative movement of the second tubular member with respect to the outer cylinder and a locked state that prevents relative movement of the second tubular member with respect to the outer cylinder.

[0010] One or more embodiments of the present invention are a work machine in which the distance between the second case portion and the outer cylinder when the telescopic mechanism is in the shortest state is longer than the length of the locking mechanism in the specified direction.

[0011] One or more embodiments of the present invention are a work machine in which caps are provided on the base end of the second tubular member and the tip end of the third tubular member, and the abutment of the caps restricts movement of the second tubular member toward the base end.

[0012] In one or more embodiments of the present invention, the first case portion has a support portion, and the support portion supports the base end of the third tubular member from the base end side of the telescopic mechanism.

[0013] One or more embodiments of the present invention are a work machine in which, when viewed from the specified direction, the portion that supports the third tubular member by the support portion extends continuously or intermittently in the circumferential direction of the third tubular member.

[0014] One or more embodiments of the present invention are a work machine in which the third tubular member has a support hole formed therethrough in a direction perpendicular to a predetermined direction, and the first case portion has a support pillar formed therein whose axial direction is the perpendicular direction, and the support pillar is inserted into the support hole and abuts against the inner periphery of the support hole.

[0015] One or more embodiments of the present invention include a telescopic mechanism including a drive unit, a main body having an operating unit that is actuated by the drive force of the drive unit, a grip to be held by an operator, and a telescopic mechanism that extends in a predetermined direction, the grip unit being provided at a base end and the main body being provided at a tip end, and that is configured to be telescopic in the predetermined direction, the telescopic mechanism including an outer tube including a first cylindrical member to which a first case portion that constitutes either the grip unit or the main body is fixed, and a front end inserted into the outer tube so as to be movable relative to the outer tube, the front end The work machine comprises a second tubular member to which a second case portion constituting the other of the grip portion and the main body portion is fixed, a third tubular member provided inside the outer tube, a first cap provided at the base end of the second tubular member, and a second cap provided at the tip end of the third tubular member, and when the telescopic mechanism is in the shortest position, the first cap abuts against the second cap, thereby restricting movement of the second tubular member toward the base end, and the first cap has the same outermost shape as the second cap when viewed from a predetermined direction. [Effects of the Invention]

[0016] One or more embodiments of the present invention can provide improved convenience. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a cross-sectional view of the chainsaw according to the present embodiment in the shortest position as viewed from the right side. [Figure 2] 2 is an enlarged cross-sectional view showing the periphery of the handle of the chain saw shown in FIG. 1. FIG. [Figure 3] 2 is an enlarged cross-sectional view showing a rear portion of the telescopic pipe of the chain saw shown in FIG. 1. FIG. [Figure 4] 2 is an enlarged cross-sectional view showing the periphery of a front end portion of an extendable pipe of the chain saw shown in FIG. 1. FIG. [Figure 5] 2 is an exploded perspective view of a handle housing in the handle portion of the chain saw shown in FIG. 1. FIG. [Figure 6] FIG. 2 is an exploded perspective view of the telescopic pipe of the chain saw shown in FIG. 1. [Figure 7](A) is a cross-sectional view from the rear (cross-sectional view taken along line 7A-7A in FIG. 3) showing the state in which the tip pipe shown in FIG. 3 is inserted into the outer pipe, and (B) is a cross-sectional view from the front (cross-sectional view taken along line 7B-7B in FIG. 3) showing the state in which the inner pipe shown in FIG. 3 is inserted into the outer pipe. [Figure 8] 8 is a cross-sectional view (cross-sectional view taken along line 8-8 in FIG. 3) seen from the rear side, showing a state in which the cap shown in FIG. 3 is inserted into the outer pipe. [Figure 9] 3 is a cross-sectional view seen from the rear, showing the positional relationship between a support wall of the handle portion and an inner pipe shown in FIG. 2. FIG. [Figure 10] 2 is a cross-sectional view showing a state in which the tip pipe of the chainsaw shown in FIG. 1 has moved forward relative to the outer pipe and the telescopic pipe has been extended. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0018] Below, a chainsaw 10 as a work machine according to this embodiment will be described with reference to the drawings. Note that the arrows UP, FR, and RH shown as appropriate in the drawings respectively indicate the upper side, front side, and right side of the chainsaw 10. In the following description, when the up-down, front-rear, and left-right directions are used, they refer to the up-down, front-rear, and left-right directions of the chainsaw 10 unless otherwise specified.

[0019] 1, the chainsaw 10 is formed in a generally elongated shape extending in the front-to-rear direction as a whole. The chainsaw 10 includes a handle 20 as a grip, a chainsaw body 40 as a main body, and an extendable pipe 50 as an extendable mechanism.

[0020] (Regarding the handle portion 20) As shown in Figures 2 and 5, the handle portion 20 forms the rear end (base end) of the chainsaw 10. The handle portion 20 has a handle housing 22 as a first case portion, and the handle housing 22 forms the outer shell of the handle portion 20. The handle housing 22 is configured to include a handle main body 22A extending in the front-to-rear direction and a guard portion 22B extending downward from the handle main body 22A. The guard portion 22B is formed in a substantially U-shape that is open upward when viewed from the left and right. The front end of the guard portion 22B is connected to a front-to-rear intermediate portion of the handle main body 22A, and the rear end of the guard portion 22B is connected to the rear end of the handle main body 22A. The portion of the handle main body 22A between the front and rear ends of the guard portion 22B forms a grip portion 22C that is held by the operator.

[0021] The handle housing 22 is composed of housing members 24L and 24R divided in two in the left-right direction, and the housing member 24R is fastened to the housing member 24L by a screw SC1. At the front end of the portion of the housing member 24L that constitutes the handle main body 22A, fixing bosses 22D (see FIGS. 2 and 3) are formed as a pair of front and rear support pillars for fastening and fixing the housing member 24R. The fixing boss 22D is formed in a substantially cylindrical shape with its axial direction extending in the left-right direction and protrudes to the right from the left wall of the housing member 24L. Four ribs 22D1 are formed on the outer periphery of the fixing boss 22D. The ribs 22D1 extend in the axial direction of the fixing boss 22D, with the circumferential direction of the fixing boss 22D being the plate thickness direction. One rib 22D1 protrudes upward from the fixing boss 22D, and four ribs 22D1 are arranged at equal intervals around the circumferential direction of the fixing boss 22D.

[0022] At the front end of the portion of the housing member 24R that constitutes the handle main body 22A, fixed bosses 22E (see FIG. 5) are formed as a pair of front and rear support columns at positions corresponding to the fixed bosses 22D. The fixed boss 22E is formed in a cylindrical shape with its axial direction extending in the left-right direction and protrudes to the left from the right wall of the housing member 24R. The fixed boss 22E has a larger diameter than the fixed boss 22D, and when the housing members 24R and 24L are fastened together, the tip of the fixed boss 22D is inserted into the fixed boss 22E. Four ribs 22E1 are formed on the outer periphery of the fixed boss 22E. The ribs 22E1 extend in the axial direction of the fixed boss 22E, with the circumferential direction of the fixed boss 22E being the plate thickness direction. One rib 22E1 protrudes upward from the fixed boss 22E, and four ribs 22E1 are arranged at equal intervals around the circumferential direction of the fixed boss 22E.

[0023] 9, a support wall 22F serving as a support portion is formed at the front end of the handle main body 22A, rearward of the fixing boss 22D and the fixed boss 22E. The support wall 22F is formed in a generally annular plate shape with its thickness in the front-to-rear direction, and protrudes from the inner periphery of the handle main body 22A toward the inside of the handle portion 20. The support wall 22F is divided into two in the left-right direction, with the left support wall 22F being formed integrally with the housing member 24L and the right support wall 22F being formed integrally with the housing member 24R.

[0024] As shown in FIG. 2 , a trigger 30 is provided on the grip portion 22C of the handle housing 22. The trigger 30 extends in the front-rear direction, and its rear end is rotatably connected to the handle housing 22 with the left-right direction as its axial direction. The trigger 30 protrudes downward from the grip portion 22C and is configured to be pulled upward. A trigger biasing spring 32 is provided on the handle portion 20. The trigger biasing spring 32 is a compression coil spring that biases the trigger 30 downward. The handle housing 22 restricts downward rotation of the trigger 30, thereby holding the trigger 30 in the handle housing 22. A trigger switch 34 is provided inside the handle housing 22, above the front end of the trigger 30. The trigger switch 34 is electrically connected to a controller (not shown) provided on the chainsaw body 40, which will be described later. When the trigger 30 is pulled upward, the trigger 30 presses the trigger switch 34, which then outputs an ON signal to the controller.

[0025] A battery mounting section 22G is provided at the rear end of the handle housing 22, and a battery 36 is mounted in the battery mounting section 22G from above. The battery 36 is electrically connected to the controller of the chainsaw body 40 and supplies power to the controller.

[0026] (Regarding the chainsaw body 40) As shown in Figure 1, the chainsaw body 40 forms the front end (tip) of the chainsaw 10. The chainsaw body 40 has a body housing 42 as a second case that forms the outer shell of the chainsaw body 40. The body housing 42 is hollow and extends in the front-to-rear direction. The body housing 42 is fixed to the front end of an extendable pipe 50, which will be described later, and the chainsaw body 40 and the handle 20 are connected by the extendable pipe 50.

[0027] A motor 44 serving as a drive unit is housed inside the main body housing 42, and the motor 44 is electrically connected to a controller provided in the main body housing 42. A transmission mechanism (not shown) including a sprocket is also provided inside the main body housing 42, and the rotational force of the motor 44 is transmitted to the sprocket by the transmission mechanism, causing the sprocket to rotate with the left-right direction as its axial direction.

[0028] A guide bar 46 is attached to the chainsaw body 40. The guide bar 46 is formed in a generally long plate shape with the left-right direction as the plate thickness direction and the front-rear direction as the length direction. When the guide bar 46 is attached, it protrudes forward from the body housing 42 in front of the sprocket. A saw chain 48 serving as an endless operating part is wound around the outer periphery of the sprocket and guide bar 46. As a result, when the sprocket is rotated by the drive of the motor 44, the saw chain 48 rotates along the outer periphery of the guide bar 46, and the rotating saw chain 48 cuts the workpiece.

[0029] (Regarding the expansion pipe 50) As shown in FIGS. 1 to 9, the telescopic pipe 50 is configured to include an outer pipe unit 60 as an outer cylinder, a tip pipe unit 80, and an inner pipe unit 90.

[0030] The outer pipe unit 60 includes an outer pipe 62 as a first cylindrical member and a locking mechanism 70. The outer pipe 62 is made of a metal material such as aluminum. The outer pipe 62 is formed in a cylindrical shape extending in the front-rear direction and is formed in a generally home base shape when viewed in the front-rear direction. Specifically, when viewed in the front-rear direction, the lower portion of the outer pipe 62 is formed in a generally semicircular shape that is open upward, and the upper portion of the outer pipe 62 is formed in a generally inverted U shape that is open downward (see FIGS. 7 to 9). The rear end of the outer pipe 62 is fixed to the front end of the handle section 20 (handle housing 22), and the outer pipe 62 extends forward from the handle section 20. Specifically, the rear end of the outer pipe 62 is sandwiched from both left and right sides between the front ends of the housing members 24L and 24R, thereby fixing the outer pipe 62 to the handle housing 22 (see FIG. 5).

[0031] A pair of front and rear positioning holes 62A (see FIG. 5) are formed in the left and right side walls of the rear end of the outer pipe 62 so as to penetrate in the left-right direction. When the outer pipe 62 is in a fixed state, the fixing boss 22D and the fixed boss 22E of the handle housing 22 are inserted into the positioning holes 62A, and the rib 22D1 of the fixing boss 22D and the rib 22E1 of the fixed boss 22E abut against the inner periphery of the positioning holes 62A. As a result, the front-rear and up-down positions of the outer pipe 62 are determined by the fixing boss 22D and the fixed boss 22E. Furthermore, when the outer pipe 62 is in a fixed state, the rear end (base end) of the outer pipe 62 is disposed adjacent to the front side of the support wall 22F (see FIG. 2).

[0032] As shown in Figures 4 and 6, a pipe cover 64 is provided at the front end of the outer pipe 62. The pipe cover 64 is formed in a substantially cylindrical shape with its axial direction extending in the front-to-rear direction. The front end of the outer pipe 62 is inserted into the pipe cover 64 from the rear, and the pipe cover 64 is fixed to the front end of the outer pipe 62 with screws SC2. A clamp portion 64A that constitutes the locking mechanism 70 is provided at the front end of the pipe cover 64, and the clamp portion 64A protrudes toward the front side of the outer pipe 62. The clamp portion 64A is formed in a substantially C-shaped cylinder that is open downward. A tip pipe 82, which will be described later, is inserted into the clamp portion 64A and the outer pipe 62.

[0033] The locking mechanism 70 is configured to include the aforementioned clamp portion 64A, a clamp bolt 72, and a lock lever 74 (which, in a broad sense, is an element that can be understood as an operating portion). The clamp bolt 72 is hung across the lower end of the clamp portion 64A with the left-right direction as its axial direction, and the threaded portion and head of the clamp bolt 72 protrude outward in the left-right direction from the clamp portion 64A. A nut 76 is threaded onto the threaded portion of the clamp bolt 72.

[0034] The lock lever 74 is formed in a generally rectangular plate shape with its thickness direction in the left-right direction and its longitudinal direction in the up-down direction. The lower end of the lock lever 74 is rotatably connected to the head of the clamp bolt 72 by a shaft 78 whose axial direction is in the front-to-rear direction. A cam is formed at the lower end of the lock lever 74. Rotating the lock lever 74 switches the lock mechanism 70 between a locked state, which prevents relative movement of the tip pipe 82 with respect to the outer pipe 62, and an unlocked state, which allows relative movement of the tip pipe 82 with respect to the outer pipe 62. Specifically, when the lock mechanism 70 is in the locked state, the cam of the lock lever 74 presses the clamp portion 64A, which clamps the tip pipe 82 and prevents relative movement of the tip pipe 82 with respect to the outer pipe 62. On the other hand, in the unlocked state, the lock lever 74 is released from pressing the clamp portion 64A, the clamp portion 64A is released from the clamped state on the tip pipe 82, and the tip pipe 82 is allowed to move relative to the outer pipe 62.

[0035] As shown in FIGS. 3, 6, and 7A, the tip pipe unit 80 includes a tip pipe 82 serving as a second tubular member and a cap 84. The tip pipe 82 is made of a metal material such as aluminum. The tip pipe 82 is formed in a tubular shape extending in the front-rear direction. When viewed from the front-rear direction, the outer shape of the tip pipe 82 is formed to be substantially similar to that of the outer pipe 62 and is set to be smaller than that of the outer pipe 62 (see FIG. 7A). Specifically, when viewed from the front-rear direction, the lower part of the tip pipe 82 is formed in a substantially semicircular shape that opens upward, and the upper part of the tip pipe 82 is formed in a substantially inverted U shape that opens downward. Pipe recesses 82A are formed in the left and right side walls of the upper part of the tip pipe 82, and the pipe recesses 82A are formed in a recessed shape that opens outward in the left-right direction. A rectangular engagement hole 82B (see FIG. 6) is formed through the bottom wall of the pipe recess 82A.

[0036] The tip pipe 82 is inserted into the outer pipe unit 60 so as to be movable relative to the outer pipe unit 60 in the front-rear direction. This allows the telescopic pipe 50 to be telescopic in the front-rear direction. Specifically, the telescopic pipe 50 is extended by moving the tip pipe 82 forward relative to the outer pipe unit 60 from its most retracted, shortest position (the state shown in FIG. 1) (see FIG. 10). When the telescopic pipe 50 is in its shortest position, the front end (tip) of the tip pipe 82 protrudes forward from the outer pipe unit 60, and the chainsaw body 40 (body housing 42) described above is fixed to the front end of the tip pipe 82 (see FIGS. 1 and 4). In other words, the chainsaw body 40 is mounted on the front end of the tip pipe 82 so as not to be movable relative to it. This allows the locking mechanism 70 to be operated to set the front-rear position of the tip pipe 82 relative to the outer pipe unit 60, thereby determining the front-rear position of the chainsaw body 40 relative to the handle 20.

[0037] The cap 84 is made of a resin material. The cap 84 is formed in a cylindrical shape with its axial direction extending in the front-rear direction. Specifically, the cap 84 includes a cylindrical portion 84A and a flange portion 84B formed on the outer periphery of the rear end of the cylindrical portion 84A. When viewed in the front-rear direction, the outer shape of the cylindrical portion 84A is substantially similar to the outer shape of the tip pipe 82 and is smaller than the outer shape of the tip pipe 82. The cylindrical portion 84A is fitted into the rear end of the tip pipe 82 from the rear side, thereby assembling the cap 84 to the tip pipe 82. Engagement claws 84C are provided on both left and right sides of the cylindrical portion 84A. The engagement claws 84C are fitted into engagement holes 82B, thereby engaging the cap 84 and the tip pipe 82. This restricts rearward movement of the cap 84. That is, the cap 84 is attached to the tip pipe 82 by a so-called snap fit.

[0038] The flange portion 84B is formed around the entire circumferential circumference of the cap 84, and when viewed from the front-to-rear direction, the outer shape of the flange portion 84B is substantially similar to, and smaller than, the outer shape of the outer pipe 62 (see FIG. 8). When the cap 84 is attached to the tip pipe 82, the flange portion 84B is disposed adjacent to the rear side of the tip pipe 82, restricting forward movement of the cap 84. When the tip pipe 82 moves forward and backward relative to the outer pipe unit 60, the flange portion 84B slides on the inner periphery of the outer pipe 62.

[0039] As shown in Figures 2, 3, 6, and 9, the inner pipe unit 90 includes an inner pipe 92 as a third tubular member and a cap 84. That is, the tip pipe unit 80 and the inner pipe unit 90 share the cap 84 as a common component. The inner pipe 92, like the tip pipe 82, is made of a metal material such as aluminum. The inner pipe 92 is formed into a cylindrical shape extending in the front-rear direction, and the cross-sectional shape of the inner pipe 92 when viewed from the front-rear direction matches the cross-sectional shape of the tip pipe 82 (see Figures 7(A) and (B)). That is, the tip pipe 82 and the inner pipe 92 have the same outer shape and thickness. Therefore, pipe recesses 92A that are open outward in the left-right direction are formed on the left and right side walls of the inner pipe 92. Furthermore, in the inner pipe unit 90, the cap 84 is arranged in a state where it is inverted front-rear with respect to the cap 84 of the tip pipe unit 80, and is attached to the front end of the inner pipe 92. Therefore, an engagement hole 92B that is engaged with the engagement claw 84C of the cap 84 is formed through the front end of the inner pipe 92 in the bottom wall of the pipe recess 92A.

[0040] The inner pipe 92 is housed inside the outer pipe 62, and the rear end of the inner pipe 92 is supported by the handle portion 20. Specifically, a pair of front and rear support holes 92C are formed in the left and right side walls of the rear end of the inner pipe 92 in the left-right direction. A fixing boss 22D and a fixed boss 22E of the handle housing 22 are inserted into the support holes 92C. When the fixing boss 22D and the fixed boss 22E are inserted into the support holes 92C, a rib 22D1 of the fixing boss 22D and a rib 22E1 of the fixed boss 22E abut against the inner periphery of the support hole 92C. As a result, the rear end of the inner pipe 92 is supported in the front-rear direction and the up-down direction by the fixing boss 22D and the fixed boss 22E, and movement of the rear end of the inner pipe 92 in the front-rear direction and the up-down direction is restricted by the fixing boss 22D and the fixed boss 22E.

[0041] Furthermore, when the inner pipe 92 is housed in the outer pipe 62, the rear end (base end) of the inner pipe 92 is disposed adjacent to the front side of the support wall 22F of the handle portion 20 and abuts against the front surface of the support wall 22F (see FIGS. 2 and 3). This allows the support wall 22F to support the inner pipe 92 from the rear side. Furthermore, the portion of the support wall 22F that supports the inner pipe 92 extends intermittently in the circumferential direction of the inner pipe 92 (see FIG. 9). In other words, the support wall 22F intermittently supports the inner pipe 92 from the rear side in the circumferential direction of the inner pipe 92.

[0042] Furthermore, when the telescopic pipe 50 is in the shortest state, the rear surface of the cap 84 of the tip pipe unit 80 abuts against the front surface of the cap 84 of the inner pipe unit 90, restricting rearward (proximal end) movement of the tip pipe 82. In other words, the inner pipe 92 abuts indirectly against the tip pipe 82 via the pair of caps 84, and functions as a stopper that restricts rearward movement of the tip pipe 82.

[0043] Furthermore, when the telescopic pipe 50 is in the shortest position, the chainsaw body 40 is positioned away from the outer pipe unit 60 toward the front. That is, as shown in Figure 4, a gap G is formed between the locking mechanism 70 and the chainsaw body 40, and the front end portion of the tip pipe 82 is exposed. In other words, the chainsaw body 40 does not come into direct contact with the locking mechanism 70. More specifically, the length of the inner pipe 92 in the front-to-rear direction is set so that the dimension L1 (separation distance) of the gap G in the front-to-rear direction is greater than the dimension L2 of the locking mechanism 70 (clamp portion 64A) in the front-to-rear direction.

[0044] Inside the telescopic pipe 50, a curled cord 94 (see FIG. 1) is provided for connecting the battery 36 and the trigger switch 34 to the controller of the chainsaw body 40.

[0045] (Action and effect) Next, the operation and effects of this embodiment will be described.

[0046] In the chainsaw 10 configured as described above, the handle 20 is provided at the rear end (base end) of the outer pipe unit 60 (outer pipe 62) of the telescopic pipe 50. The chainsaw body 40 is provided at the front end (tip end) of the tip pipe 82 of the telescopic pipe 50. In the telescopic pipe 50, the tip pipe 82 is inserted into the outer pipe unit 60 so as to be movable relative to it in the front-to-rear direction. This allows the front-to-rear position of the chainsaw body 40 relative to the handle 20 to be changed by extending or retracting the telescopic pipe 50 depending on the type of work being performed. Specifically, with the locking mechanism 70 in the unlocked state, the position of the tip pipe 82 relative to the outer pipe unit 60 is determined, and the locking mechanism 70 is switched from the unlocked state to the locked state by rotating the lock lever 74 of the locking mechanism 70. This prevents the tip pipe 82 from moving relative to the outer pipe unit 60, and fixes the chainsaw body 40 in the set front-to-rear position.

[0047] When the operator operates the trigger 30, the motor 44 of the chainsaw body 40 is driven, causing the saw chain 48 to rotate in the circumferential direction of the guide bar 46. This allows the saw chain 48 to perform cutting on the workpiece.

[0048] In the telescopic pipe 50 of the chainsaw 10, the inner pipe 92 is provided inside the outer pipe unit 60. When the telescopic pipe 50 is in the shortest position, the inner pipe 92 restricts rearward (proximal end) movement of the tip pipe 82. Specifically, the inner pipe 92 indirectly contacts the tip pipe 82 via the cap 84, restricting the rearward movement of the tip pipe 82. Furthermore, when viewed from the front-to-rear direction, the tip pipe 82 and the inner pipe 92 have the same cross-sectional shape. Therefore, the tip pipe 82 moving rearward can be supported by the entire tip surface of the inner pipe 92. In other words, the collision load generated when the tip pipe 82 moving rearward hits the inner pipe 92 can be supported by the entire cross section of the inner pipe 92. This reduces damage to the inner pipe 92 compared to a configuration in which the collision load is input locally to the inner pipe 92. Therefore, replacement of the inner pipe 92 due to damage is not required, improving user convenience.

[0049] Furthermore, because the tip pipe 82 and the inner pipe 92 have the same cross-sectional shape, the inner pipe 92 can be manufactured inexpensively. That is, for example, when the tip pipe 82 and the inner pipe 92 are molded by extrusion molding, the same mold can be used to mold the tip pipe 82 and the inner pipe 92. In other words, the inner pipe 92 can be molded using the mold for the tip pipe 82. Therefore, the inner pipe 92 can be manufactured inexpensively.

[0050] The inner pipe 92 is formed in a cylindrical shape. That is, the inner pipe 92 has a closed cross-sectional structure. This allows the inner pipe 92 to receive the tip pipe 82 while ensuring the mechanical strength of the inner pipe 92, which functions as a stopper, when the telescopic pipe 50 is in the shortest state.

[0051] Furthermore, when the telescopic pipe 50 is in the shortest position, the chainsaw body 40 is positioned at a distance forward from the outer pipe unit 60. This makes it possible to prevent the chainsaw body 40 from colliding with the outer pipe unit 60 when the telescopic pipe 50 is in the shortest position, thereby improving the protection performance of the chainsaw body 40.

[0052] A locking mechanism 70 is provided at the tip of the outer pipe 62, and the locking mechanism 70 can be switched between an unlocked state, which allows the tip pipe 82 to move relative to the outer pipe unit 60, and a locked state, which prevents the tip pipe 82 from moving relative to the outer pipe unit 60. This prevents the chainsaw body 40 from colliding with the locking mechanism 70 when the telescopic pipe 50 is shortened. Therefore, the protective performance of the locking mechanism 70, which fixes the telescopic pipe 50 at a predetermined length, can be improved while the locking mechanism 70 is provided at the tip of the outer pipe 62.

[0053] Furthermore, the front-to-rear dimension L1 of the gap G between the chainsaw body 40 and the outer pipe unit 60 when the telescopic pipe 50 is in the shortest position is set to be longer than the front-to-rear dimension L2 of the locking mechanism 70. More specifically, the front-to-rear dimension L1 of the gap G is set to be longer than the front-to-rear dimension of the locking lever 74 of the locking mechanism 70. This ensures a sufficient gap between the locking mechanism 70 and the chainsaw body 40 when the telescopic pipe 50 is in the shortest position. As a result, it is possible to prevent the operator's hand from coming into contact with the chainsaw body 40 when operating the locking lever 74 when the telescopic pipe 50 is in the shortest position. This therefore improves operability when operating the locking mechanism 70.

[0054] Furthermore, caps 84 are provided on the rear end of the tip pipe 82 and the front end of the inner pipe 92, and when the telescopic pipe 50 is in the shortest state, the caps 84 abut against each other, restricting rearward movement of the tip pipe 82. This allows the caps 84 to function as a shock absorber, for example. Also, by appropriately setting the shape of the caps 84, it is possible to increase the abutting area between the caps 84 when the telescopic pipe 50 is in the shortest state. This makes it possible to distribute the collision load input to the caps 84 of the inner pipe unit 90 when the tip pipe unit 80 abuts against the inner pipe unit 90. This can therefore contribute to reducing damage to the caps 84.

[0055] The handle portion 20 also has a support wall 22F, which supports the inner pipe 92 from the rear side. As a result, the collision load input to the inner pipe 92 when the telescopic pipe 50 is brought to the shortest state can be transmitted to the handle portion 20 by the support wall 22F, and dispersed to the handle portion 20.

[0056] Furthermore, when viewed from the front-rear direction, the portion of the support wall 22F that supports the inner pipe 92 extends discontinuously in the circumferential direction of the inner pipe 92. This allows the support wall 22F to receive the collision load input to the inner pipe 92 approximately uniformly in the circumferential direction of the inner pipe 92 and transmit the load to the handle portion 20. This reduces damage to the support wall 22F.

[0057] Furthermore, a fixing boss 22D and a fixed boss 22E, whose axial direction is the left-right direction, are formed on the inner periphery of the handle housing 22 of the handle section 20, and a support hole 92C of the inner pipe 92 is inserted into the fixing boss 22D and the fixed boss 22E. When the fixing boss 22D and the fixed boss 22E are inserted into the support hole 92C, the rib 22D1 of the fixing boss 22D and the rib 22E1 of the fixed boss 22E abut against the inner periphery of the support hole 92C. This allows the collision load input to the inner pipe 92 when the telescopic pipe 50 is in the shortest state to be transmitted to the handle section 20 while being distributed among the support wall 22F, the fixing boss 22D, and the fixed boss 22E.

[0058] In this embodiment, the tip pipe 82 and the inner pipe 92 have the same cross-sectional shape when viewed from the front-to-rear direction. However, the cross-sectional shape of the inner pipe 92 may be different from that of the tip pipe 82. For example, the inner pipe 92 may be formed into a substantially rectangular tubular shape. Furthermore, when changing the cross-sectional shape of the inner pipe 92, the tubular portion 84A of the cap 84 assembled to the inner pipe 92 may be formed into a substantially rectangular shape corresponding to the inner pipe 92. In this case, the cap 84 assembled to the tip pipe 82 corresponds to the first cap of the present invention, and the cap 84 assembled to the inner pipe 92 corresponds to the second cap of the present invention. The outermost shapes of the flange portions 84B of the cap 84 assembled to the tip pipe 82 and the cap 84 assembled to the inner pipe 92 are formed to be the same shape, as in this embodiment.

[0059] Furthermore, in this embodiment, when the telescopic pipe 50 is in the shortest state, the tip pipe 82 indirectly abuts against the inner pipe 92 via the cap 84, but the tip pipe 82 may also be made to abut directly against the inner pipe 92. In other words, the cap 84 may be omitted from the tip pipe unit 80 and the inner pipe unit 90.

[0060] Furthermore, in the present embodiment, the portion of the support wall 22F of the handle portion 20 that supports the inner pipe 92 extends discontinuously in the circumferential direction of the inner pipe 92, but the shape of the support wall 22F may be appropriately modified so that the support portion extends continuously in the circumferential direction of the inner pipe 92. In other words, the support wall 22F may be configured to support the inner pipe 92 from the rear side over the entire circumferential circumference of the inner pipe 92.

[0061] Furthermore, the present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit and scope of the present invention. The motor serving as the drive unit may be provided in the handle unit rather than in the chainsaw body unit, and the driving force of the motor may be transmitted to an operating unit such as a saw chain via a transmission mechanism such as a flexible shaft inserted through the telescopic pipe. The telescopic pipe may be reversed from the front to the back in the above-described embodiment, with the outer pipe fixed to the chainsaw body unit and the tip pipe fixed to the handle housing. In this case, the main body housing is an example of a first case unit. The present invention may also be applied to equipment such as lawnmowers, in which the operating unit is placed in contact with the ground. [Explanation of symbols]

[0062] 10 Chainsaw (working equipment) 20 Handle (grip) 22 Handle housing (first case part) 22D Fixed boss (support column) 22E Fixed boss (support column) 22F Support wall (support part) 40 Chainsaw body (body) 42 Main body housing (second case part) 44 Motor (drive unit) 48 Saw chain (operating part) 50 Telescopic pipe (telescopic mechanism) 60 Outer pipe unit (outer cylinder) 62 Outer pipe (first cylindrical member) 70 Locking mechanism 82 Tip pipe (second cylindrical member) 84 Cap 92 Inner pipe (third cylindrical member) L1: The distance between the main body and the outer tube when the telescopic mechanism is in the shortest position L2 Locking mechanism length

Claims

1. A drive unit; a main body having an actuating part that is actuated by the driving force of the driving part; a gripping portion to be gripped by an operator; an extension mechanism that extends in a predetermined direction, has the grip portion provided at a base end and the main body portion provided at a tip end, and is configured to be extendable and contractible in the predetermined direction; Equipped with The extension mechanism is an outer cylinder including a first cylindrical member to which a first case portion constituting either the grip portion or the main body portion is fixed; a second cylindrical member inserted into the outer cylinder so as to be movable relative to the outer cylinder, and having a second case portion fixed thereto, the second case portion constituting the other of the grip portion and the main body portion; a third cylindrical member provided inside the outer cylinder and restricting movement of the second cylindrical member toward the base end side when the telescopic mechanism is in the shortest position; The invention comprises: A work machine in which the second tubular member and the third tubular member have the same cross-sectional shape when viewed from the predetermined direction.

2. The work machine according to claim 1, wherein, in the shortest state of the telescopic mechanism, the second case portion is disposed at a distance toward the tip end of the outer cylinder.

3. the outer cylinder has a locking mechanism provided at a tip end of the first cylindrical member, The work machine according to claim 2, wherein the locking mechanism is configured to be switchable between an unlocked state that permits relative movement of the second tubular member with respect to the outer tube and a locked state that prevents relative movement of the second tubular member with respect to the outer tube.

4. The work machine according to claim 3, wherein a distance between the second case portion and the outer cylinder when the extension mechanism is in the shortest position is longer than a length of the locking mechanism in the predetermined direction.

5. The work machine according to claim 1, wherein caps are provided on the base end of the second tubular member and the tip end of the third tubular member, and the abutment of the caps restricts movement of the second tubular member toward the base end.

6. The work machine according to claim 1 , wherein the first case portion has a support portion, and the support portion supports a base end of the third tubular member from a base end side of the telescopic mechanism.

7. The work machine according to claim 6, wherein when viewed from the predetermined direction, a portion of the support portion that supports the third tubular member extends continuously or intermittently in the circumferential direction of the third tubular member.

8. a support hole penetrating the third cylindrical member in a direction perpendicular to a predetermined direction, and a support pillar having an axial direction aligned with the perpendicular direction is formed in the first case portion; The work machine according to claim 1, wherein the support post is inserted into the support hole and abuts against an inner periphery of the support hole.

9. A drive unit; a main body having an actuating part that is actuated by the driving force of the driving part; a gripping portion to be gripped by an operator; an extension mechanism that extends in a predetermined direction, has the grip portion provided at a base end and the main body portion provided at a tip end, and is configured to be extendable and contractible in the predetermined direction; Equipped with The extension mechanism is an outer cylinder including a first cylindrical member to which a first case portion constituting either the grip portion or the main body portion is fixed; a second cylindrical member inserted into the outer cylinder so as to be movable relative to the outer cylinder, and having a second case portion fixed thereto, the second case portion constituting the other of the grip portion and the main body portion; a third cylindrical member provided inside the outer cylinder; a first cap provided at a base end of the second cylindrical member; a second cap provided at a tip end of the third cylindrical member; Equipped with When the telescopic mechanism is in the shortest position, the first cap abuts against the second cap, restricting movement of the second tubular member toward the base end, and the outermost shape of the first cap when viewed from a specified direction is the same as that of the second cap.

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