Power unit

Abstract

To provide a technique that allows a pull-in part to be disposed in a proper posture according to a type of a work unit.SOLUTION: A power unit comprises: a driving motor; a body housing supporting the driving motor; and an input unit which controls the driving motor. The input unit comprises: an input unit housing having an internal space, and provided with a pull-in part for pulling in a wire from outside of the input unit housing to the internal space; and a fixing part for fixing the input unit housing to the body housing. The input unit housing can be selectively fixed to the body housing in at least two postures.SELECTED DRAWING: Figure 14

Description

[Technical field]

[0001] The technology disclosed in this specification relates to a power unit. [Background technology]

[0002] Patent Document 1 discloses a power unit. The power unit includes a prime mover, a base that supports the prime mover, and an input unit that controls the prime mover. The input unit includes an input unit main body that is fixed to the base, a pull-in portion that is disposed on the input unit main body and pulls in a wire into the input unit main body, and a fixing portion that fixes the input unit main body to the base. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2000-175310 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned power unit, the retractable part is fixed in a specific position relative to the base. Therefore, when the power unit is used with a working unit, the retractable part cannot be placed in an appropriate position depending on the type of working unit. This specification provides a technology that can place the retractable part in an appropriate position depending on the type of working unit. [Means for solving the problem]

[0005] This specification discloses a power unit. The power unit includes a prime mover, a main body housing that supports the prime mover, and an input unit that controls the prime mover. The input unit includes an input unit housing having an internal space and including a pull-in portion that pulls in a wire from the outside of the input unit housing into the internal space, and a fixing portion that fixes the input unit housing to the main body housing. The input unit housing can be selectively fixed to the main body housing in at least two positions.

[0006] According to the above configuration, the attitude of the retraction part relative to the main body housing can be adjusted by changing the attitude of the input unit housing relative to the main body housing. Therefore, when the power unit is used with a working unit, the retraction part can be placed in an appropriate attitude depending on the type of working unit. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a perspective view of a power unit 2 and a working unit 4 of the first embodiment. [Diagram 2] FIG. 2 is a perspective view of a power unit 2 of the first embodiment. [Diagram 3] FIG. 2 is a perspective view of a power unit 2 of the first embodiment. [Figure 4] FIG. 2 is an exploded perspective view of a right main body housing 42 and a cover unit 110 according to the first embodiment. [Diagram 5] FIG. 2 is an exploded perspective view of the left main body housing 44 and the input unit 112 of the first embodiment. [Figure 6] FIG. 2 is a cross-sectional view of a power unit 2 of the first embodiment. [Figure 7] FIG. 2 is a perspective view of a power unit 2 of the first embodiment. [Figure 8] FIG. 2 is a perspective view of a power unit 2 of the first embodiment. [Figure 9] FIG. 2 is a perspective view of a support member 142 according to the first embodiment. [Figure 10] FIG. 2 is a perspective view of a cover 144 according to the first embodiment. [Figure 11] FIG. 2 is a perspective view of a cover 144 according to the first embodiment. [Figure 12] 2 is a side view of the input unit 112, the handle 20, and the trigger 22 of the first embodiment. FIG. [Figure 13] 2 is a side view of the input unit 112, the handle 20, and the trigger 22 of the first embodiment. FIG. [Figure 14] 1A to 1C are side views showing the positions of the retractable portion 188 of the input unit 112 in each posture in the first embodiment. [Figure 15] FIG. 11 is a side view of the vicinity of an input unit 112 in a power unit 2 of a second embodiment. [Figure 16] FIG. 11 is a side view of the vicinity of an input unit 112 in a power unit 2 of a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Representative, non-limiting embodiments of the present invention are described in detail below with reference to the drawings. This detailed description is intended simply to provide those skilled in the art with details for implementing preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Additionally, the additional features and inventions disclosed may be used separately or in conjunction with other features and inventions to provide further improved power units, methods of making and using the same.

[0009] In addition, the combinations of features and steps disclosed in the following detailed description are not essential for implementing the present invention in the broadest sense, but are specifically described only to illustrate representative embodiments of the present invention. Furthermore, the various features of the following representative embodiments and the various features described in the claims do not have to be combined in the exact manner of the embodiments described herein or in the order listed in order to provide additional and useful embodiments of the present invention.

[0010] All features described in the specification and / or claims are intended to be disclosed individually and independently of one another as limitations to the specific features described in the original disclosure and claims, apart from the configuration of features described in the examples and / or claims. Furthermore, all numerical ranges and group or aggregate descriptions are intended to disclose intermediate configurations thereof as limitations to the specific features described in the original disclosure and claims.

[0011] In one or more embodiments, the at least two orientations may include a first orientation and a second orientation different from the first orientation. The input unit in the first orientation may be arranged rotationally symmetrical with the input unit in the second orientation with respect to a fixed central axis.

[0012] According to the above configuration, the distance between the retraction portion and the fixed central axis can be kept constant regardless of the attitude of the input unit.

[0013] In one or more embodiments, the at least two positions may include a third position different from the first position and the second position. The input unit in the third position may be arranged rotationally symmetrical with respect to the input unit in the first position with respect to a fixed central axis. An angle about the fixed central axis between the retraction part in the first position and the retraction part in the second position may be the same as an angle about the fixed central axis between the retraction part in the second position and the retraction part in the third position.

[0014] According to the above configuration, the attitude of the input unit with respect to the main body housing can be easily adjusted.

[0015] In one or more embodiments, the main body housing may include a first outer wall to which the input unit housing can be secured, and a second outer wall, different from the first outer wall, to which the input unit housing can be secured.

[0016] According to the above configuration, the outer wall to which the input unit housing is fixed can be selected from the first outer wall and the second outer wall depending on the type of the working unit, so that the retraction section can be positioned in an appropriate position depending on the type of the working unit.

[0017] In one or more embodiments, the wire may be movable relative to the lead-in portion. The input unit may further include a detector disposed in the interior space to detect movement of the wire.

[0018] According to the above configuration, it is possible to prevent the input unit from becoming large in size, compared to a configuration in which the detector is disposed outside the input unit housing.

[0019] In one or more embodiments, the input unit may further comprise a lever fixed to the wire for operating the detector when the wire moves relative to the lead.

[0020] In a configuration in which the wire directly operates the detector, the detector may be erroneously operated due to vibration of the wire, etc. With the above configuration, the lever operates the detector, so that erroneous operation of the detector can be suppressed.

[0021] In one or more embodiments, the prime mover may be a motor.

[0022] Generally, a motor is smaller than an engine, and therefore the main body housing is compact. With the above configuration, the retraction portion can be disposed in an appropriate position in the compact main body housing depending on the type of working unit.

[0023] (First embodiment) 1, the power unit 2 is used while being fixed to a working unit 4. The power unit 2 is selectively applicable to various working units 4. The power unit 2 causes the working unit 4 to operate.

[0024] The working unit 4 is a push-type grass cutter. The working unit 4 includes a housing 8, a plurality of wheels 10, a handle unit 14, and a working part 16. In Fig. 1, the direction perpendicular to the placement surface P is referred to as the up-down direction, the direction perpendicular to the front-rear direction is referred to as the front-rear direction, and the direction perpendicular to the up-down direction and the front-rear direction is referred to as the left-right direction.

[0025] The multiple wheels 10 are rotatably supported by the housing 8. The handle unit 14 includes a fixed frame 18, a handle 20, and a trigger 22. The fixed frame 18 is fixed to the housing 8. The handle 20 is attached to the fixed frame 18. When a user grips the handle 20 and pushes it forward, the multiple wheels 10 rotate. This causes the working unit 4 to move on the placement surface P. The trigger 22 is rotatably attached to the handle 20. The trigger 22 is operated by the hand of the user holding the handle 20 to move closer to the handle 20. When the trigger 22 is operated, the power unit 2 operates.

[0026] The working section 16 includes a drum 24, a transmission shaft 26, and a blade 28. The drum 24 is rotatably supported by the housing 8. The blade 28 is fixed to the drum 24 via the transmission shaft 26. When the power unit 2 operates, the drum 24 rotates. As a result, the blade 28 rotates integrally with the transmission shaft 26. The rotating blade 28 cuts grass growing on the mounting surface P.

[0027] As shown in Figures 2 and 3, the power unit 2 operates using power from the battery pack BP. In the following, the coordinate system will be changed to a different coordinate system from the above-mentioned one. Specifically, the direction in which a shaft 102 (see Figure 6) of a prime mover 96 (described later) extends is called the front-rear direction, the direction perpendicular to the front-rear direction is called the left-right direction, and the direction perpendicular to the front-rear direction and the left-right direction is called the up-down direction.

[0028] The power unit 2 includes a main body housing 40. The main body housing 40 is made of a resin material. The main body housing 40 includes a right main body housing 42 and a left main body housing 44. The right main body housing 42 defines the outer shape of the right half of the main body housing 40. The left main body housing 44 defines the outer shape of the left half of the main body housing 40. The right main body housing 42 and the left main body housing 44 have a shape obtained by dividing the main body housing 40 in half on a plane including the front-rear and up-down directions. An accommodation space 46 (see FIG. 6) is defined between the right main body housing 42 and the left main body housing 44.

[0029] The main body housing 40 includes a right wall 50, a left wall 52, a bottom wall 54, a rear upper wall 56, a front upper wall 58, a rear wall 60, a front vertical wall 62, and a front horizontal wall 64. The left wall 52 is disposed on the opposite side to the right wall 50. The bottom wall 54 comes into contact with a mounting surface P (see FIG. 1) when the power unit 2 is placed on the mounting surface P.

[0030] The rear upper wall 56 and the front upper wall 58 are disposed on the opposite side to the lower wall 54. A main power switch 66 is disposed on the front upper wall 58. The main power switch 66 receives a user's operation to switch the power unit 2 between an on state and an off state. The front vertical wall 62 extends upward from the front end of the lower wall 54. The front horizontal wall 64 extends forward from the upper end of the front vertical wall 62.

[0031] The main body housing 40 further includes a battery mounting portion 68, a right fixing portion 70, and a left fixing portion 72. The battery mounting portion 68 is disposed on the upper rear wall 56. A battery pack BP is detachably attached to the battery mounting portion 68. The battery pack BP includes a chargeable and dischargeable secondary battery, for example, a lithium ion battery.

[0032] 4, the right fixing part 70 is disposed on the right wall 50. The right fixing part 70 includes a right peripheral wall part 74, a right communication hole 76, a plurality of (four in this embodiment) right fixing holes 78, and a plurality of (two in this embodiment) right positioning protrusions 80.

[0033] The right peripheral wall portion 74 protrudes rightward from the outer surface of the right wall 50. When the main body housing 40 is viewed from the leftward direction, the right peripheral wall portion 74 has a generally square frame shape.

[0034] The right communication hole 76 penetrates the right wall 50 in the left-right direction. The right communication hole 76 is surrounded by the right peripheral wall portion 74. The right communication hole 76 communicates between the accommodation space 46 of the main body housing 40 (see FIG. 6) and the external space of the main body housing 40.

[0035] The right fixing hole 78 penetrates the right wall 50 in the left-right direction. The four right fixing holes 78 are arranged in the right peripheral wall portion 74. Each of the four right fixing holes 78 is arranged near each of the four corners of the right peripheral wall portion 74. The right fixing portion 70 has a right fixing central axis C1 that is arranged at a position equidistant from each of the four right fixing holes 78. Adjacent right fixing holes 78 are spaced 90 degrees apart around the right fixing central axis C1.

[0036] The right positioning protrusion 80 protrudes to the right from the outer surface of the right wall 50. The right positioning protrusion 80 is disposed within the right peripheral wall portion 74. The right positioning protrusion 80 is disposed closer to the right fixed central axis C1 than the right fixing hole 78. The two right positioning protrusions 80 are spaced 180 degrees apart around the right fixed central axis C1.

[0037] 5, the left fixing part 72 is disposed on the left wall 52. The left fixing part 72 includes a left peripheral wall part 82, a left communication hole 84, a plurality of (four in this embodiment) left fixing holes 86, and a plurality of (two in this embodiment) left positioning protrusions 88.

[0038] The left peripheral wall portion 82 protrudes leftward from the outer surface of the left wall 52. When the main housing 40 is viewed from the rightward, the left peripheral wall portion 82 has a generally square frame shape. The shape of the left peripheral wall portion 82 is generally the same as the shape of the right peripheral wall portion 74.

[0039] The left communication hole 84 penetrates the left wall 52 in the left-right direction. The left communication hole 84 is surrounded by the left peripheral wall portion 82. The left communication hole 84 communicates the accommodation space 46 of the main body housing 40 (see FIG. 6) with the external space of the main body housing 40.

[0040] The left fixing hole 86 penetrates the left wall 52 in the left-right direction. The four left fixing holes 86 are arranged in the left peripheral wall portion 82. The number of the left fixing holes 86 is the same as the number of the right fixing holes 78. The four left fixing holes 86 are arranged near the four corners of the left peripheral wall portion 82. The left fixing portion 72 has a left fixing center axis C2 that is arranged at a position equidistant from the four left fixing holes 86. The distance from the left fixing center axis C2 to the left fixing hole 86 is approximately the same as the distance from the right fixing center axis C1 to the right fixing hole 78. Adjacent left fixing holes 86 are spaced 90 degrees apart around the left fixing center axis C2.

[0041] The left positioning protrusion 88 protrudes leftward from the outer surface of the left wall 52. The left positioning protrusion 88 is disposed within the left peripheral wall portion 82. The left positioning protrusion 88 is disposed closer to the left fixed central axis C2 than the left fixing hole 86. The two left positioning protrusions 88 are spaced 180 degrees apart around the left fixed central axis C2.

[0042] As shown in Fig. 6, the power unit 2 includes a control unit 92, a motor housing 94, a prime mover 96, a cooling fan 98, and an output unit 100. Note that the internal structure of the battery pack BP is not shown in Fig. 6. The control unit 92, the motor housing 94, the prime mover 96, the cooling fan 98, and the output unit 100 are disposed in the accommodation space 46. The control unit 92, the motor housing 94, and the output unit 100 are supported by being sandwiched between the right main body housing 42 (see Fig. 2) and the left main body housing 44 (see Fig. 3).

[0043] The control unit 92 operates using power supplied from the battery pack BP. The control unit 92 operates the prime mover 96 when the trigger 22 (see FIG. 1) is operated.

[0044] The prime mover 96 is accommodated in a motor housing 94. The prime mover 96 is supported by the main body housing 40 via the motor housing 94. The prime mover 96 is a motor, for example a brushless motor. In a modified example, the prime mover 96 may be an internal combustion engine. When the power unit 2 is in the on state and the trigger 22 (see FIG. 1 ) is operated, a shaft 102 of the prime mover 96 rotates. The rotation speed of the shaft 102 gradually increases from zero as the amount of operation of the trigger 22 increases.

[0045] The maximum output value of the prime mover 96 may be 0.5 kW or more and 2.0 kW or less, for example, 0.5 kW or more and 1.5 kW or less, for example, 0.5 kW or more and 1.2 kW or less, for example, 0.5 kW or more and 1.0 kW or less. The prime mover 96 of this embodiment is a low-output type prime mover.

[0046] The cooling fan 98 is fixed to a shaft 102. The cooling fan 98 rotates integrally with the shaft 102. In this way, the cooling fan 98 pressurizes and blows air.

[0047] The output unit 100 is inserted into the front end opening of the main housing 40. The output unit 100 includes a fixed base portion 104 and a clutch portion 106. The fixed base portion 104 is fixed to the main housing 40. The fixed base portion 104 is fixed to the housing 8 (see FIG. 1) of the working unit 4. The clutch portion 106 is rotatably supported by the fixed base portion 104. The clutch portion 106 is fixed to the shaft 102. When the rotation speed of the shaft 102 reaches or exceeds a predetermined value, the clutch portion 106 comes into contact with the drum 24 (see FIG. 1) of the working unit 4. As a result, the rotation of the shaft 102 is transmitted to the drum 24 via the clutch portion 106, causing the blade 28 (see FIG. 1) to rotate.

[0048] As shown in Figs. 2 and 3, the power unit 2 includes a cover unit 110 and an input unit 112. As shown in Figs. 3 and 7, the cover unit 110 is selectively fixed to the right fixing portion 70 of the right wall 50 and the left fixing portion 72 of the left wall 52. As shown in Figs. 2 and 8, the input unit 112 is selectively fixed to the right fixing portion 70 and the left fixing portion 72. As shown in Figs. 2 and 3, when the cover unit 110 is fixed to the right fixing portion 70, the input unit 112 is fixed to the left fixing portion 72. As shown in Figs. 7 and 8, when the cover unit 110 is fixed to the left fixing portion 72, the input unit 112 is fixed to the right fixing portion 70.

[0049] 4, the cover unit 110 includes a cover 114, a guide member 116, and a plurality of cover fixing members 118. When the cover 114 is viewed from the left, the cover 114 has a substantially square shape. When the cover unit 110 is fixed to the right wall 50, the cover 114 is surrounded by the right peripheral wall portion 74. The cover 114 has an intake port 120 and a plurality of cover fixing holes 122 (four in this embodiment).

[0050] The intake port 120 and the four cover fixing holes 122 penetrate the cover 114 in the left-right direction. The number of the cover fixing holes 122 is the same as the number of the right fixing holes 78. The four cover fixing holes 122 are disposed near the four corners of the cover 114. Adjacent cover fixing holes 122 are spaced 90 degrees apart around the right fixed center axis C1.

[0051] When the guide member 116 is viewed to the left, the guide member 116 has a substantially square shape. The guide member 116 is sandwiched between the right wall 50 of the main body housing 40 and the cover 114. The guide member 116 has an intake passage 124, a plurality of (four in this embodiment) guide fixing holes 126, and a plurality of (four in this embodiment) guide positioning holes 128.

[0052] The intake passage 124 communicates with the external space of the main housing 40 via the intake port 120. The intake passage 124 communicates with the accommodation space 46 at its lower end. When the cooling fan 98 (see FIG. 6) rotates, air passes through the intake port 120 and the intake passage 124 and flows into the accommodation space 46. This cools the control unit 92 (see FIG. 6) and the prime mover 96 (see FIG. 6).

[0053] The guide fixing hole 126 and the guide positioning hole 128 penetrate the guide member 116 in the left-right direction. The number of the guide fixing holes 126 is the same as the number of the right fixing holes 78. The four guide fixing holes 126 are disposed near the four corners of the guide member 116. Adjacent guide fixing holes 126 are spaced 90 degrees apart around the right fixed center axis C1.

[0054] The four guide positioning holes 128 are disposed near the four corners of the guide member 116. The guide positioning holes 128 are disposed closer to the center of the guide member 116 than the guide fixing holes 126. The guide member 116 is positioned with respect to the right wall 50 by inserting each right positioning protrusion 80 into the corresponding guide positioning hole 128. When the cover unit 110 is fixed to the left fixing portion 72 (see FIG. 5), the guide member 116 is positioned with respect to the left wall 52 by inserting each left positioning protrusion 88 (see FIG. 5) into the corresponding guide positioning hole 128.

[0055] The cover fixing member 118 is, for example, a screw. The cover fixing member 118 is inserted into the cover fixing hole 122 and the guide fixing hole 126, and is screwed into the thread of the right fixing hole 78. This fixes the cover unit 110 to the right wall 50. In a modified example, the cover unit 110 may be fixed to the right wall 50 using a tapping screw as the cover fixing member 118. When fixing the cover unit 110 to the left wall 52 (see FIG. 5), the cover fixing member 118 is inserted into the left fixing hole 86 (see FIG. 5), the cover fixing hole 122, and the guide fixing hole 126.

[0056] 5, the input unit 112 includes an input unit housing 130, a pipe 132, a wire W, a lever 134, a biasing member 136 (FIG. 12), a detector 138, and a plurality of (four in this embodiment) fixing members 140. The input unit housing 130 includes a support member 142 and a cover 144.

[0057] The support member 142 includes a base plate portion 150, a first guide portion 152, a second guide portion 154, a first support portion 156, a second support portion 158, a third support portion 160, a first stopper portion 162, and a second stopper portion 164.

[0058] The base plate portion 150 has a substantially square shape. The base plate portion 150 is sandwiched between the left wall 52 and the cover 144 of the main body housing 40. When the input unit 112 is fixed to the left wall 52, the base plate portion 150 is surrounded by the left peripheral wall portion 82. The base plate portion 150 has a plate communication hole 166, a plurality of (four in this embodiment) plate fixing holes 168, and a plurality of (four in this embodiment) plate positioning holes 170. The plate communication hole 166, the plate fixing hole 168, and the plate positioning hole 170 penetrate the base plate portion 150 in the left-right direction.

[0059] The plate communication hole 166 is disposed in the lower part of the base plate portion 150. The plate communication hole 166 faces the left communication hole 84 in the left-right direction. The plate communication hole 166 has a substantially right-angled triangular shape.

[0060] As shown in FIG. 9, the number of the plate fixing holes 168 is the same as the number of the left fixing holes 86 (see FIG. 5). The four plate fixing holes 168 are disposed near the four corners of the base plate portion 150. The center 150a of the base plate portion 150 is disposed on the left fixing central axis C2. The center 150a is disposed at an equal distance from the four plate fixing holes 168. The distance from the center 150a to the plate fixing hole 168 is approximately the same as the distance from the left fixing central axis C2 to the left fixing hole 86. Adjacent plate fixing holes 168 are spaced 90 degrees apart around the left fixing central axis C2.

[0061] The plate positioning hole 170 is disposed closer to the center 150a than the plate fixing holes 168. The center 150a is disposed at a position equidistant from the four plate positioning holes 170. Each of the four plate positioning holes 170 is disposed near each of the four plate fixing holes 168. As shown in FIG. 5, the support member 142 is positioned with respect to the left wall 52 by inserting each left positioning protrusion 88 into the corresponding plate positioning hole 170. When the input unit 112 is fixed to the right fixing part 70 (see FIG. 4), the support member 142 is positioned with respect to the right wall 50 by inserting each right positioning protrusion 80 (see FIG. 4) into the corresponding plate positioning hole 170.

[0062] 9, the first guide portion 152, the second guide portion 154, the first support portion 156, the second support portion 158, the third support portion 160, the first stopper portion 162, and the second stopper portion 164 protrude leftward from the base plate portion 150 when the input unit 112 (see FIG. 2) is fixed to the left wall 52 (see FIG. 2), and protrude rightward from the base plate portion 150 when the input unit 112 (see FIG. 8) is fixed to the right wall 50 (see FIG. 8). The protruding direction is opposite when the input unit 112 is fixed to the left wall 52 and when the input unit 112 is fixed to the right wall 50.

[0063] The first guide portion 152 is disposed below an upper front corner of the base plate portion 150. The first guide portion 152 is disposed on the periphery of the base plate portion 150. The first guide portion 152 has a first recess 152a recessed from a tip of the first guide portion 152.

[0064] The second guide portion 154 faces the first guide portion 152 in the front-rear direction. The second guide portion 154 has a second recess 154a recessed from the tip of the second guide portion 154. The second recess 154a is aligned with the first recess 152a in the front-rear direction.

[0065] The first support portion 156 has a substantially L-shape. One end of the first support portion 156 is disposed in the vicinity of the plate communication hole 166. The vicinity of the other end of the first support portion 156 is connected to the second guide portion 154.

[0066] The second support portion 158 has a curved shape. One end of the second support portion 158 is disposed near the plate communication hole 166. The other end of the second support portion 158 is disposed near the lower rear corner of the base plate portion 150.

[0067] The third support portion 160 has a substantially cylindrical shape. The third support portion 160 is disposed in the vicinity of the second support portion 158.

[0068] The first stopper portion 162 has a substantially L-shape. The first stopper portion 162 faces the second stopper portion 164.

[0069] The second stopper portion 164 has a substantially T-shape. The second stopper portion 164 protrudes upward toward the rear from the other end of the first support portion 156.

[0070] 10, the cover 144 has a generally box-like shape. The cover 144 defines an internal space 174 between itself and the support member 142 (see FIG. 9). The cover 144 includes a bottom portion 176, a side portion 178, and a third guide portion 180.

[0071] As shown in FIG. 11, when the input unit housing 130 is viewed in the right direction, the bottom 176 has a substantially square shape. The bottom 176 faces the support member 142 (see FIG. 9). The bottom 176 has a plurality of (four in this embodiment) cover fixing holes 184 penetrating the bottom 176 in the left-right direction. The number of the plurality of cover fixing holes 184 is the same as the number of the plurality of left fixing holes 86 (see FIG. 5). Each of the four cover fixing holes 184 is disposed near each of the four corners of the bottom 176. The center 176a of the bottom 176 is disposed on the left fixed central axis C2. The center 176a is disposed at a position equidistant from the four cover fixing holes 184. The distance from the center 176a to the cover fixing holes 184 is substantially the same as the distance from the left fixed central axis C2 to the left fixing hole 86 (see FIG. 5). Adjacent cover fixing holes 184 are spaced apart by 90 degrees around the left fixed central axis C2.

[0072] The side portion 178 protrudes to the right from the peripheral edge of the bottom portion 176. The side portion 178 goes around the peripheral edge of the bottom portion 176. When the input unit 112 is fixed to the left wall 52 (see FIG. 5), the side portion 178 is surrounded by the left peripheral wall portion 82 (see FIG. 5).

[0073] The input unit housing 130 has a retraction portion 188, which is formed in the side portion 178. The retraction portion 188 is disposed in the vicinity of an upper front corner of the bottom portion 176. The retraction portion 188 penetrates the front wall of the side portion 178 in the front-rear direction. The retraction portion 188 is a through hole.

[0074] The third guide portion 180 is disposed in a portion of the retraction portion 188. The third guide portion 180 has a substantially semi-cylindrical shape. As shown in FIG. 5, the third guide portion 180 abuts against the tip of the first guide portion 152. The first guide portion 152 is disposed within the retraction portion 188. As a result, a retraction hole 190 is formed by the third guide portion 180 and the first recess 152a of the first guide portion 152. The retraction hole 190 is a portion of the retraction portion 188. The retraction hole 190 communicates between the outside of the input unit housing 130 and the internal space 174 (see FIG. 10).

[0075] The pipe 132 is sandwiched between the first guide part 152 and the third guide part 180. As shown in Fig. 12, the pipe 132 is received in the first recess 152a and the second recess 154a. The pipe 132 has a substantially cylindrical shape. The pipe 132 is fixed to the second guide part 154 by two nuts 192 and two washers 194.

[0076] The wire W is inserted into the pipe 132. Therefore, the wire W passes through a retraction portion 188 (see FIG. 10) and is retracted from the external space of the input unit housing 130 into the internal space 174 (see FIG. 10). One end of the wire W is fixed to the trigger 22. The other end of the wire W is fixed to the lever 134.

[0077] The lever 134 includes a rotating portion 198, a wire fixing portion 200, and a switch operation portion 202. The rotating portion 198 is rotatably attached to the third support portion 160. The wire fixing portion 200 protrudes from the rotating portion 198. The tip of the wire fixing portion 200 is fixed to the other end of the wire W. When the lever 134 rotates, the wire fixing portion 200 moves between the first stopper portion 162 and the second stopper portion 164. The switch operation portion 202 protrudes from the switch operation portion 202 toward the detector 138.

[0078] The biasing member 136 is attached to the lever 134. The biasing member 136 is, for example, a torsion spring. One end 136a of the biasing member 136 is engaged with the switch operation portion 202. The other end 136b of the biasing member 136 is engaged with the first stopper portion 162. The biasing member 136 biases the lever 134 toward a position where the wire fixing portion 200 abuts against the first stopper portion 162.

[0079] The detector 138 is, for example, a push switch. The detector 138 includes a main body portion 206, a switch portion 208, and a wiring connection portion 210. The main body portion 206 has a substantially rectangular parallelepiped shape. The main body portion 206 is at least partially surrounded by the first support portion 156 and the second support portion 158, and is supported by the first support portion 156 and the second support portion 158.

[0080] The switch portion 208 is disposed on a side surface of the main body portion 206. The switch portion 208 is pressed into the switch operation portion 202.

[0081] The wiring connection portion 210 is disposed on a side surface of the main body portion 206. The wiring connection portion 210 is adjacent to the plate communication hole 166. The wiring connection portion 210 is connected to the control unit 92 (see FIG. 6) via a wiring 212. The wiring 212 passes through the plate communication hole 166 .

[0082] When the trigger 22 is not operated by the user, the wire fixing part 200 abuts against the first stopper part 162 due to the biasing force of the biasing member 136. As shown in FIG. 13, when the trigger 22 is operated, the wire W is pulled and the other end of the wire W moves toward the first guide part 152 and the second guide part 154 (i.e., the retraction part 188). The wire fixing part 200 moves toward the second stopper part 164, and the lever 134 moves. At this time, the switch operating part 202 pushes the switch part 208. As a result, the detector 138 detects that the other end of the wire W moves toward the retraction part 188, that is, that the wire W has been pulled. The trigger 22 can be operated until the wire fixing part 200 abuts against the second stopper part 164. When the wire fixing part 200 abuts against the second stopper part 164, the lever 134 cannot move further. As a result, switch section 208 is pushed to a predetermined position. This prevents detector 138 from being pushed beyond the predetermined position, and prevents detector 138 from being damaged. A signal corresponding to the amount of depression of switch section 208 (a signal corresponding to the amount of operation of trigger 22) is transmitted to control unit 92 (see FIG. 6) via wiring 212. Control unit 92 controls the rotation speed of shaft 102 of prime mover 96 based on the received signal.

[0083] 5, the fixing member 140 is, for example, a screw. The fixing member 140 is inserted into the plate fixing hole 168 and the cover fixing hole 184, and is screwed into the thread of the left fixing hole 86. This fixes the input unit 112 to the left wall 52. When fixing the input unit 112 to the right wall 50 (see FIG. 4), the fixing member 140 is inserted into the right fixing hole 78, the plate fixing hole 168, and the cover fixing hole 184.

[0084] As shown in FIG. 14, by changing the combination of the left fixing hole 86, the plate fixing hole 168, and the cover fixing hole 184, the input unit 112 is selectively fixed to the left wall 52 in four positions. In the first position, the retractable portion 188 faces forward. In the second position, the retractable portion 188 faces upward. In the third position, the retractable portion 188 faces rearward. In the fourth position, the retractable portion 188 faces downward. The input unit 112 in the first position is arranged rotationally symmetrical with the input unit 112 in the second position, the input unit 112 in the third position, and the input unit 112 in the fourth position, with the left fixed central axis C2 as the reference. Because adjacent left fixing holes 86 are spaced 90 degrees apart about the left fixed central axis C2, the angle A1 about the left fixed central axis C2 between the retraction portion 188 in the first position and the retraction portion 188 in the second position is 90 degrees. Also, the angle A1 is the same as the angle A2 about the left fixed central axis C2 between the retraction portion 188 in the second position and the retraction portion 188 in the third position, the angle A3 about the left fixed central axis C2 between the retraction portion 188 in the third position and the retraction portion 188 in the fourth position, and the angle A4 about the left fixed central axis C2 between the retraction portion 188 in the fourth position and the retraction portion 188 in the first position.

[0085] Also, by changing the combination of the right fixing hole 78, the plate fixing hole 168, and the cover fixing hole 184, the input unit 112 is selectively fixed to the right wall 50 (see FIG. 8) in four positions. As shown in FIG. 8, in the first position, the retractable portion 188 faces forward. Although not shown, in the second position, the retractable portion 188 faces upward. In the third position, the retractable portion 188 faces backward. In the fourth position, the retractable portion 188 faces downward. Also, the input unit 112 in the first position is arranged rotationally symmetrical with the input unit 112 in the second position, the input unit 112 in the third position, and the input unit 112 in the fourth position, with the right fixed central axis C1 as a reference.

[0086] 4, in the cover unit 110, the guide member 116 is fixed to the right wall 50 or the left wall 52 (see FIG. 7) in a specific position in which the lower end of the intake passage 124 faces downward. Therefore, in the cover unit 110, only the cover 114 is selectively fixed to the right wall 50 in four positions and selectively fixed to the left wall 52 in four positions.

[0087] (effect) The power unit 2 of this embodiment includes a prime mover 96, a main body housing 40 that supports the prime mover 96, and an input unit 112 that controls the prime mover 96. The input unit 112 includes an input unit housing 130 having an internal space 174 and including a pull-in portion 188 that pulls in the wire W from the outside of the input unit housing 130 into the internal space 174, and a cover fixing hole 184 and a fixing member 140 (an example of a fixing portion) that fix the input unit housing 130 to the main body housing 40. The input unit housing 130 can be selectively fixed to the main body housing 40 in at least two positions.

[0088] According to the above configuration, the attitude of the retraction part 188 relative to the main body housing 40 can be adjusted by changing the attitude of the input unit housing 130 relative to the main body housing 40. Therefore, when the power unit 2 is used with the working unit 4, the retraction part 188 can be placed in an appropriate attitude depending on the type of working unit 4.

[0089] Moreover, the at least two attitudes include a first attitude and a second attitude different from the first attitude. The input unit 112 in the first attitude is disposed rotationally symmetrically with the input unit 112 in the second attitude with respect to the left fixed central axis C2 (an example of a fixed central axis).

[0090] According to the above configuration, regardless of the attitude of the input unit 112, the distance between the retraction portion 188 and the left fixed central axis C2 can be kept constant.

[0091] In addition, the at least two postures include a third posture different from the first posture and the second posture. The input unit 112 in the third posture is disposed rotationally symmetrical to the input unit 112 in the first posture with respect to the left fixed central axis C2. The angle between the retraction portion 188 in the first posture and the retraction portion 188 in the second posture about the left fixed central axis C2 is the same as the angle between the retraction portion 188 in the second posture and the retraction portion 188 in the third posture about the left fixed central axis C2.

[0092] According to the above configuration, the attitude of the input unit 112 relative to the main body housing 40 can be easily adjusted.

[0093] The main body housing 40 also has a right wall 50 (an example of a first outer wall) to which the input unit housing 130 can be fixed, and a left wall 52 (an example of a second outer wall) different from the right wall 50 to which the input unit housing 130 can be fixed.

[0094] According to the above configuration, the outer wall to which the input unit housing 130 is fixed can be selected from the right wall 50 and the left wall 52 depending on the type of working unit 4. This allows the retraction portion 188 to be positioned in an appropriate position depending on the type of working unit 4.

[0095] In addition, the wire W is movable relative to the retraction portion 188. The input unit 112 is disposed in the internal space 174 and further includes a detector 138 that detects the movement of the wire W.

[0096] According to the above configuration, compared to a configuration in which the detector 138 is disposed outside the input unit housing 130, it is possible to prevent the input unit 112 from becoming large.

[0097] The input unit 112 also includes a lever 134 fixed to the wire W for manipulating the detector 138 when the wire W moves relative to the retraction portion 188 .

[0098] In a configuration in which the wire W directly operates the detector 138, the detector 138 may be erroneously operated due to vibration or the like of the wire W. According to the above configuration, the lever 134 operates the detector 138, so that erroneous operation of the detector 138 can be suppressed.

[0099] Moreover, the prime mover 96 is a motor.

[0100] Generally, a motor is smaller than an engine, and therefore the main body housing 40 is compact. According to the above configuration, in the small main body housing 40, the retraction portion 188 can be disposed in an appropriate position depending on the type of working unit 4.

[0101] (Second Example) In the second embodiment, only the points different from the first embodiment will be described. As shown in FIG. 15, the input unit 112 is fixed to the left wall 52 by one fixing member 140. The fixing member 140 is arranged on the left fixed central axis C2. After the input unit 112 is rotated around the left fixed central axis C2 to adjust the retraction portion 188 to a desired orientation, the fixing member 140 is inserted into the input unit housing 130 on the left fixed central axis C2 and screwed into the left wall 52. This adjusts the attitude of the input unit 112 to a desired attitude. Although not shown, the fixing member 140 is inserted into the input unit housing 130 on the right fixed central axis C1 and screwed into the right wall 50 (see FIG. 4), thereby fixing the input unit 112 to the right wall 50.

[0102] (Third Example) In the third embodiment, only the differences from the first embodiment will be described. As shown in Fig. 16, the cover 144 of the input unit housing 130 has an insertion portion 300. The left wall 52 has a receiving portion 302 into which the insertion portion 300 is inserted.

[0103] The cover 144 also has two cover fixing holes 184. Each of the two cover fixing holes 184 is disposed near two of the four corners of the bottom portion 176.

[0104] When fixing the input unit 112 to the left wall 52, first, the inserting portion 300 is inserted into the inserted portion 302. Next, each of the two fixing members 140 is inserted into the corresponding cover fixing hole 184 and plate fixing hole 168, and screwed into the thread of the left fixing hole 86. This prevents the inserting portion 300 from slipping out of the inserted portion 302. As a result, the input unit 112 is fixed to the left wall 52.

[0105] Although not shown, the right wall 50 (see FIG. 4) has an insertion portion having a configuration similar to that of the insertion portion 302 of the left wall 52. Therefore, the input unit 112 is fixed to the right wall 50 using the insertion structure between the insertion portion 300 and the insertion portion of the right wall 50.

[0106] (Modification) The work unit 4 according to one embodiment is not limited to a grass cutter, but may be, for example, a lawn mower, a hedge trimmer, a blower, a transporter, a snow blower, a tiller, an edger, a winch, a concrete vibrator, a screed, a rammer, a plate compactor, or a trowel.

[0107] The input unit 112 according to an embodiment may be selectively fixed to each of the right wall 50 and the left wall 52 in two positions, three positions, or five or more positions. When the input unit 112 is selectively fixed to each of the right wall 50 and the left wall 52 in N positions, the angle A1 may be 360 / N degrees. For example, when N is 2, the angle A1 is 180 degrees, and when N is 3, the angle A1 is 120 degrees.

[0108] In the input unit 112 according to an embodiment, the angles A1, A2, A3, and A4 may not be the same, for example, may be different from each other.

[0109] In the input unit 112 according to one embodiment, the right fixing hole 78 may not be disposed near a corner of the right peripheral wall portion 74. For example, the right fixing hole 78 may be disposed near the center position of two corners of the right peripheral wall portion 74, or may be disposed at a position shifted toward the center position from the position of the right fixing hole 78 in the first embodiment. Moreover, the left fixing hole 86 may not be disposed near a corner of the left peripheral wall portion 82. For example, the left fixing hole 86 may be disposed near the center position of two corners of the left peripheral wall portion 82, or may be disposed at a position shifted toward the center position from the position of the left fixing hole 86 in the first embodiment.

[0110] The input unit 112 according to one embodiment may be selectively fixed to the right wall 50 and the left wall 52 using only two or three fixing members 140. In this case, the fixing members 140 are not inserted into some of the right fixing holes 78 and some of the left fixing holes 86.

[0111] The fixing member 140 according to one embodiment may include a pin and a retaining member fixed to the pin instead of a screw. In this case, the input unit 112 may be selectively fixed to the right wall 50 and the left wall 52 by the pin and the retaining member. Furthermore, the multiple fixing members 140 may include both the screw and the pin and the retaining member.

[0112] The detector 138 according to an embodiment may be a non-contact detector, such as a photointerrupter, or a magnetic sensor including a Hall element and a magnet.

[0113] The detector 138 according to one embodiment may detect whether the switch portion 208 is pressed or not, instead of detecting the amount by which the switch portion 208 is pressed. In this configuration, the control unit 92 rotates the prime mover 96 at a constant rotation speed, regardless of the amount by which the switch portion 208 is pressed. [Explanation of symbols]

[0114] 2: Power unit 4: Unit of Work 22: Trigger 40: Main housing 46: Containment space 50: Right wall 52: Left wall 70: Right fixed part 72:Left fixed part 78: Right fixing hole 86:Left fixing hole 96: Prime mover 102: Shaft 110: Cover unit 112: Input unit 122: Cover fixing hole 126: Guide fixing hole 130: Input unit housing 134: Lever 138: Detector 140: Fixing member 142: Support member 144: Cover 150: Base plate part 150a: center 168: Plate fixing hole 174: Interior space 176a :Center 184: Cover fixing hole 188: Retraction section A1, A2, A3, A4: Angle BP: Battery pack C1: Right fixed center axis C2: Left fixed center axis P: Placement surface W: Wire

Claims

1. The prime mover, a main body housing supporting the prime mover; an input unit for controlling the prime mover, The input unit includes: An input unit housing having an internal space, the input unit housing including a lead-in portion for leading a wire from an outside of the input unit housing into the internal space; a fixing portion that fixes the input unit housing to the main body housing, A power unit, wherein the input unit housing is selectively securable to the main body housing in at least two positions.

2. The at least two positions are: The first position, a second attitude different from the first attitude, The power unit according to claim 1 , wherein the input unit in the first attitude is disposed rotationally symmetrical to the input unit in the second attitude with respect to a fixed central axis.

3. the at least two positions include a third position different from the first position and the second position; the input unit in the third attitude is disposed rotationally symmetrically with respect to the input unit in the first attitude with respect to the fixed central axis; 3. The power unit according to claim 2, wherein an angle about the fixed central axis between the retraction portion in the first position and the retraction portion in the second position is the same as an angle about the fixed central axis between the retraction portion in the second position and the retraction portion in the third position.

4. The main body housing includes: a first outer wall to which the input unit housing can be fixed; 4. A power unit according to claim 1, further comprising a second outer wall to which the input unit housing can be fixed, the second outer wall being different from the first outer wall.

5. The wire is movable relative to the retractor; The power unit according to claim 1 , wherein the input unit is disposed in the internal space and further comprises a detector for detecting movement of the wire.

6. 6. The power unit of claim 5, wherein the input unit further comprises a lever fixed to the wire for operating the detector when the wire moves relative to the retract.

7. A power unit according to any one of claims 1 to 6, wherein the prime mover is a motor.

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