Lawn management machine

Abstract

To provide a technique that can restrain liquid from flowing into a housing.SOLUTION: A lawn management machine comprises: a pair of wheels to be rotated on the ground; a handle unit to be held by a user when the lawn management machine is moved; a working unit for working on the ground; an electric motor for driving the working unit; a fan to be rotated by driving of the electric motor; a housing supporting the working unit, and housing the electric motor and the fan; and a wall body arranged outside the housing, and attached to the housing. The housing has a communication opening which establishes communication between the inside and the outside of the housing, and through which air passes in association with rotation of the fan. The wall body is arranged opposite to the communication opening.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The technology disclosed herein relates to a turf management machine. [Background technology]

[0002] Patent Document 1 discloses a lawnmower. The lawnmower includes a pair of wheels that rotate on the ground, a handle unit that is held by a user when moving the lawnmower, a working unit that works on the ground, an electric motor that drives the working unit, and a housing that supports the working unit and contains the electric motor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 8-256554 Summary of the Invention [Problem to be solved by the invention]

[0004] In a working machine such as that described in Patent Document 1, in order to cool the motor, the housing communicates between the inside and outside of the housing and may have a communication opening through which air can pass. In such a working machine, for example, when the working machine is washed with liquid, the liquid may pass through the communication opening and flow into the inside of the housing. This specification provides a technology that can suppress the liquid from flowing into the inside of the housing. [Means for solving the problem]

[0005] This specification discloses a lawn care machine. The lawn care machine performs maintenance on the grass on the ground while moving forward on the ground. The lawn care machine includes a pair of wheels that rotate on the ground, a handle unit that is held by a user when moving the lawn care machine, a working unit that works on the ground, an electric motor that drives the working unit, a fan that rotates when driven by the electric motor, a housing that supports the working unit and accommodates the electric motor and the fan, and a wall body that is disposed outside the housing and attached to the housing. The housing communicates between the inside and outside of the housing and has a communication opening through which air passes as the fan rotates. The wall body is disposed opposite the communication opening.

[0006] According to the above configuration, when the lawn care machine is being washed with liquid, the liquid can be prevented from hitting the wall and reaching the communication opening, thereby preventing the liquid from passing through the communication opening and flowing into the housing. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a perspective view of a turf management machine 2 according to an embodiment. [Diagram 2] 4 is a cross-sectional view of a connection portion between an upper housing 26 and a lower housing 28 in the embodiment. [Diagram 3] 1 is an exploded perspective view of the vicinity of a right handle bracket 110 in a state in which a right front wheel 60 is removed in a lawn trimmer 2 of an embodiment. FIG. [Figure 4] 2 is a perspective view of the vicinity of a second communication port 44 in the lawn management machine 2 of the embodiment. FIG. [Diagram 5] 1 is a perspective view of the lawn management machine 2 of the embodiment with a battery cover 14 open. FIG. [Figure 6] 2 is a cross-sectional view of the vicinity of a cutter unit 130 of the lawn management machine 2 of the embodiment. [Figure 7] 2 is a perspective view of a front wheel unit 22 and a height adjustment unit 24 according to the embodiment. FIG. [Figure 8]2 is a perspective view of the front wheel unit 22 and the height adjustment unit 24 of the embodiment, and the vicinity of the height adjustment unit 24. FIG. [Figure 9] 4 is a cross-sectional view of a height adjustment unit 24 according to the embodiment. FIG. [Figure 10] 2 is a cross-sectional view of the vicinity of a right front wheel 60 in the lawn trimmer 2 of the embodiment. [Figure 11] 2 is a cross-sectional view of the vicinity of an electric motor 122 in the lawn trimmer 2 of the embodiment. [Figure 12] 2 is a cross-sectional view of the vicinity of a second communication port 44 in the lawn management machine 2 of the embodiment. [Figure 13] FIG. 2 is a perspective view of an electric motor 122, a fan 126, a transmission unit 128, and a cutter unit 130 of the embodiment. [Figure 14] 2 is a cross-sectional view of the vicinity of a cutter unit 130 in the lawn management machine 2 of the embodiment. [Figure 15] FIG. 13 is a perspective view of a mounting unit 178 according to the embodiment. [Figure 16] FIG. 13 is a perspective view of a mounting unit 178 according to the embodiment. [Figure 17] 13 is an exploded perspective view of the vicinity of a right shaft insertion opening 198 in the mounting unit 178 of the embodiment. FIG. [Figure 18] 13 is an exploded perspective view of the vicinity of the left shaft insertion opening 216 in the mounting unit 178 of the embodiment. FIG. [Figure 19] 1 is a left side view of the battery mounting unit 16, the battery pack BP, the front wheel unit 22, the control unit 120, the electric motor 122, the fan 126, and the cutter unit 130 of the embodiment. [Figure 20] 1 is a rear view of the battery mounting unit 16, the battery pack BP, the front wheel unit 22, the control unit 120, the electric motor 122, the fan 126, and the cutter unit 130 of the embodiment. [Figure 21] 1 is a top view of a battery mounting unit 16, a battery pack BP, a front wheel unit 22, a control unit 120, an electric motor 122, a fan 126, and a cutter unit 130 of the embodiment. [Figure 22]FIG. 2 is a perspective view of a cutter unit 130 according to the embodiment. [Diagram 23] FIG. 2 is a perspective view of a shaft 232 according to an embodiment. [Figure 24] FIG. 2 is an exploded perspective view of a cutter unit 130 according to the embodiment. [Diagram 25] FIG. 2 is a front view of a cutter unit 130 according to the 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 can be used separately or together with other features and inventions to provide further improved turf management machines, 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 wall may be disposed between the communication opening and the wheel.

[0012] When the lawn care machine moves on the ground, dirt and grass may adhere to the wheels. With the above-mentioned configuration, even when the wheels are washed with liquid, the liquid hits the wall and is prevented from reaching the communication opening. This makes it possible to prevent the liquid from passing through the communication opening and flowing into the housing.

[0013] In one or more embodiments, the wall may be a handle bracket that connects the handle unit and the housing.

[0014] According to the above configuration, the handle unit and the housing can be connected with a single part, and liquid can be prevented from passing through the communicating opening and flowing into the inside of the housing when the lawn care machine is being washed with liquid.

[0015] In one or more embodiments, when the turf trimmer is viewed along the axis of rotation of the pair of wheels, the electric motor may at least partially overlap the wheels.

[0016] According to the above-mentioned configuration, the electric motor, which is a heavy object, is disposed near the ground. This makes it possible to prevent the housing from tilting relative to the ground when an external force acts on the housing, compared to a configuration in which the electric motor is not disposed near the ground.

[0017] In one or more embodiments, the turf management machine may further include a control unit contained in the housing and configured to control the electric motor. When viewed from the rear of the turf management machine, the control unit may at least partially overlap the electric motor.

[0018] When the fan rotates, air passes through the electric motor. With the above configuration, the distance between the electric motor and the control unit can be shortened. This allows the control unit to be more effectively cooled by the air passing through the electric motor.

[0019] In one or more embodiments, the control unit may be located forward of the electric motor.

[0020] According to the above configuration, the space behind the electric motor can be made more compact than in a configuration in which the control unit is disposed behind the electric motor, and therefore, for example, when the working unit is disposed behind the electric motor, the distance between the electric motor and the working unit can be shortened.

[0021] In one or more embodiments, the turf trimmer may further include a battery that provides power to the electric motor. When the turf trimmer is viewed along the axis of rotation of the pair of wheels, the battery may at least partially overlap the electric motor.

[0022] According to the above configuration, the battery, which is a heavy object, is disposed near the ground. This makes it possible to prevent the housing from tilting relative to the ground when an external force acts on the housing, compared to a configuration in which the battery is not disposed near the ground.

[0023] In one or more embodiments, the housing may have a drain hole that is disposed on the ground side of the communication opening and communicates between the inside and the outside of the housing. The drain hole may be disposed in a position facing the wheels.

[0024] According to the above configuration, even if liquid passes through the communication opening and flows into the inside of the housing, the liquid can be discharged to the outside of the housing through the drainage hole. Furthermore, when the lawn care machine is being washed with liquid, the liquid can be prevented from hitting the wheels and reaching the drainage hole. This prevents the liquid from passing through the drainage hole and flowing into the inside of the housing.

[0025] (Example) As shown in FIG. 1, the lawn maintenance machine 2 performs maintenance on the grass on the ground G (see FIG. 6) while moving over the ground G. Specifically, the lawn maintenance machine 2 performs thatching to remove dead grass and leaves on the ground G, and grass that has fallen due to mowing (thatch). The lawn maintenance machine 2 also performs aeration to supply oxygen to the roots and soil of the grass on the ground G by tilling the ground G. Furthermore, the lawn maintenance machine 2 performs cutting to cut the grass on the ground G.

[0026] The lawn management machine 2 comprises a main unit 4, a grass collection box 6, and a handle unit 8. The grass collection box 6 is detachably attached to the rear end of the main unit 4. The grass collection box 6 collects grass cut by the lawn management machine 2 and grass and leaves that have fallen on the ground G. The handle unit 8 is attached to the main unit 4. A user stands behind the lawn management machine 2 and moves the lawn management machine 2 by gripping the upper part of the handle unit 8 with both hands and pushing it forward or pulling it backward. Hereinafter, the direction in which the lawn management machine 2 moves and that is along the ground G is referred to as the front-rear direction, the direction perpendicular to the ground G is referred to as the up-down direction, and the direction perpendicular to the front-rear direction and the up-down direction is referred to as the left-right direction.

[0027] The main unit 4 includes a housing 12, a battery cover 14, a battery mounting unit 16 (see FIG. 5), a battery pack BP (see FIG. 5), a right rear wheel 18, a left rear wheel 20, a front wheel unit 22, and a height adjustment unit 24 (see FIG. 7). The housing 12 includes an upper housing 26 that defines the outer shape of an upper portion of the housing 12, and a lower housing 28 that defines the outer shape of a lower portion of the housing 12. The housing 12 has an internal space 30 (see FIG. 6) that is defined by the upper housing 26 and the lower housing 28.

[0028] As shown in FIG. 2, at the location where the upper housing 26 is connected to the lower housing 28, an upper abutment surface 31 of the upper housing 26 abuts against a lower abutment surface 32 of the lower housing 28. The upper housing 26 includes an upper protruding wall 34 and a receiving groove 36. The upper protruding wall 34 protrudes downward from the upper abutment surface 31. The upper protruding wall 34 is exposed to the outside of the turf management machine 2. The lower end of the upper protruding wall 34 is disposed below the lower abutment surface 32. The receiving groove 36 is recessed upward from the upper abutment surface 31. The receiving groove 36 is disposed closer to the internal space 30 than the upper protruding wall 34. The lower housing 28 includes a lower protruding wall 38. The lower protruding wall 38 protrudes upward from the lower abutment surface 32. The lower protruding wall 38 is received in the receiving groove 36. The upper protruding wall 34, the receiving groove 36, and the lower protruding wall 38 form a labyrinth structure, which makes it possible to prevent liquid from passing between the upper housing 26 and the lower housing 28 and entering the internal space 30.

[0029] As shown in FIG. 3 and FIG. 4, the housing 12 includes a first communication port 40, a first drain hole 42, a second communication port 44, and a second drain hole 46. As shown in FIG. 3, the first communication port 40 and the first drain hole 42 are disposed in the right front part of the lower housing 28. The first communication port 40 and the first drain hole 42 are disposed below the connection part between the upper housing 26 and the lower housing 28 (i.e., on the ground G side). The first communication port 40 and the first drain hole 42 penetrate the lower housing 28 in the left-right direction. The first communication port 40 and the first drain hole 42 communicate the internal space 30 (see FIG. 6) of the housing 12 with the outside. The first communication port 40 includes a plurality of first communication openings 48 arranged in the front-rear direction. The first communication openings 48 are elongated openings in the up-down direction. The first drainage hole 42 is disposed below the first communication port 40 (ie, on the ground G side).

[0030] As shown in FIG. 1 and FIG. 4, the second communication port 44 and the second drainage hole 46 are disposed in the front right part of the lower housing 28. The second communication port 44 and the second drainage hole 46 are disposed below the connection part between the upper housing 26 and the lower housing 28 (i.e., on the ground G side). As shown in FIG. 4, the second communication port 44 penetrates the lower housing 28 in the front-rear direction. The second drainage hole 46 penetrates the lower housing 28 in the up-down direction. The second communication port 44 and the second drainage hole 46 communicate the internal space 30 (see FIG. 6) of the housing 12 with the outside. The second communication port 44 has a plurality of second communication openings 50 arranged in the left-right direction. The second communication openings 50 are elongated openings in the up-down direction. The second drainage hole 46 is disposed below the second communication port 44 (i.e., on the ground G side). The second drain hole 46 is disposed rearward of the second communication port 44 .

[0031] As shown in FIG. 5, the upper housing 26 has a recess 52 recessed downward from the upper surface, and the battery cover 14 is attached to the upper housing 26 at a position forward of the recess 52. The battery cover 14 rotates between a closed position (see FIG. 6) and an open position. The rotation axis of the battery cover 14 is disposed in front of the recess 52. As shown in FIG. 6, when the battery cover 14 is in the closed position, the battery cover 14 covers the recess 52. This defines an accommodation space 54 between the upper housing 26 and the battery cover 14. The recess 52 constitutes a part of the accommodation space 54. As shown in FIG. 5, when the battery cover 14 is in the open position, the recess 52 is not covered.

[0032] The battery mounting unit 16 is fixed to the upper housing 26 within the recess 52. Two battery packs BP are detachably attached to the battery mounting unit 16. In FIG. 5, one battery pack BP is omitted from the illustration in order to make the battery mounting unit 16 easier to see. The two battery packs BP are arranged side by side in the left-right direction. The battery pack BP is attached to the battery mounting unit 16 by sliding the battery pack BP forward and downward relative to the battery mounting unit 16 with the battery cover 14 in the open position, and is removed from the battery mounting unit 16 by sliding the battery pack BP backward and upward relative to the battery mounting unit 16. The battery pack BP includes a secondary battery, such as a lithium-ion battery.

[0033] 1, the right rear wheel 18 is rotatably attached near the rear right end of the lower housing 28. The left rear wheel 20 is rotatably attached near the rear left end of the lower housing 28. The front wheel unit 22 is attached near the front end of the lower housing 28. The height adjustment unit 24 is fixed to the upper left part of the upper housing 26.

[0034] As shown in FIG. 7, the front wheel unit 22 includes a shaft 58, a right front wheel 60, and a left front wheel 62. As shown in FIG. 7 and FIG. 8, the shaft 58 includes a central shaft portion 64, a right connecting portion 66, a right shaft portion 68, a left connecting portion 70, a left shaft portion 72, a plate portion 74, and a pin portion 76. The central shaft portion 64 extends in the left-right direction. As shown in FIG. 6, the central shaft portion 64 is attached to the lower part of the front end of the lower housing 28 from below. The central shaft portion 64 is rotatable with respect to the lower housing 28, and is supported by the lower housing 28 so as to be immovable in the up-down direction and the front-rear direction. As shown in FIG. 7, the rotation axis AX1 of the central shaft portion 64 extends in the left-right direction. The right connecting portion 66 connects the right end of the central shaft portion 64 and the left end of the right shaft portion 68. The right shaft portion 68 extends in the left-right direction. The right shaft portion 68 is disposed at a position offset relative to the central shaft portion 64. The right shaft portion 68 rotatably supports the right front wheel 60. The right front wheel 60 rotates about a rotation axis AX2 extending in the left-right direction. The rotation axis AX2 is offset from the turning axis AX1.

[0035] As shown in FIG. 8, the left connection portion 70 connects the left end of the central shaft portion 64 and the right end of the left shaft portion 72. The left shaft portion 72 is disposed at a position offset from the central shaft portion 64. The central axis of the left shaft portion 72 and the central axis of the right shaft portion 68 are substantially the same. The left shaft portion 72 rotatably supports the left front wheel 62. The left front wheel 62 rotates around a rotation axis AX2. That is, the left front wheel 62 and the right front wheel 60 rotate coaxially. The plate portion 74 extends from the central shaft portion 64 in a direction perpendicular to the central shaft portion 64. The pin portion 76 protrudes leftward from the plate portion 74.

[0036] The height adjustment unit 24 is disposed on the left side of the plate portion 74. As shown in FIG. 9, the height adjustment unit 24 includes a fixed cylinder portion 80, an adjustment dial portion 82, a first cylinder portion 84, a second cylinder portion 86, and a pin operation portion 88. The fixed cylinder portion 80 is fixed to the upper housing 26 (see FIG. 1). The adjustment dial portion 82 is exposed to the outside of the upper housing 26 and is operated by a user. The adjustment dial portion 82 is supported by the fixed cylinder portion 80 so as to be rotatable around a rotation axis AX3 extending in the vertical direction. The first cylinder portion 84 and the second cylinder portion 86 are disposed inside the fixed cylinder portion 80. The first cylinder portion 84 has a substantially cylindrical shape with a bottom at the upper end. The upper end of the first cylinder portion 84 is connected to the adjustment dial portion 82. The first cylinder portion 84 rotates around the rotation axis AX3 together with the adjustment dial portion 82. The first cylinder portion 84 cannot move in the vertical direction. A male screw portion 90 extending in a spiral shape is formed on the outer peripheral surface of the first cylindrical portion 84. The second cylindrical portion 86 has a substantially cylindrical shape with a bottom at the lower end. The second cylindrical portion 86 surrounds the outer peripheral surface of the first cylindrical portion 84. The second cylindrical portion 86 is supported by the fixed cylindrical portion 80 so as not to be rotatable around the rotation axis AX3. A female screw portion 92 extending in a spiral shape is formed on the inner peripheral surface of the second cylindrical portion 86. The female screw portion 92 is screwed into the male screw portion 90. When the first cylindrical portion 84 rotates around the rotation axis AX3, the second cylindrical portion 86 moves relatively in the up-down direction with respect to the first cylindrical portion 84. The pin operating portion 88 extends downward from the lower end of the second cylindrical portion 86. The pin operating portion 88 has a pin receiving groove 94 recessed from the right surface to the left. As shown in FIG. 8, the pin receiving groove 94 has a substantially rectangular shape elongated in the front-rear direction. The pin portion 76 is received in the pin receiving groove 94 so as to be rotatable and movable in the front-rear direction.

[0037] When the adjustment dial portion 82 rotates around the rotation axis AX3, the second tube portion 86 moves up and down relative to the first tube portion 84 due to the screw structure of the male screw portion 90 and the female screw portion 92. This causes the pin operation portion 88 to move up and down. As shown in FIG. 8, when the pin operation portion 88 moves up and down, the pin portion 76 moves in the front-rear direction within the pin receiving groove 94. For example, when the pin operation portion 88 moves downward, the pin portion 76 moves in the rear direction within the pin receiving groove 94. This causes the plate portion 74 to rotate so that the connection position between the plate portion 74 and the pin portion 76 is pushed downward. As a result, the central shaft portion 64 rotates around the rotation axis AX1 in the rotation direction D1, and the right shaft portion 68 supporting the right front wheel 60 and the left shaft portion 72 supporting the left front wheel 62 move so as to be pushed downward relative to the central shaft portion 64. As a result, the housing 12 (see FIG. 6) is pushed up so as to move away from the ground G (see FIG. 6). On the other hand, when the pin operating portion 88 moves upward, the pin portion 76 moves forward within the pin receiving groove 94. As a result, the plate portion 74 rotates so that the connection position between the plate portion 74 and the pin portion 76 is pushed up. As a result, the central shaft portion 64 rotates about the rotation axis AX1 in a rotation direction D2 opposite to the rotation direction D1, and the right shaft portion 68 supporting the right front wheel 60 and the left shaft portion 72 supporting the left front wheel 62 move so as to be pushed up in the upward direction relative to the central shaft portion 64. As a result, the housing 12 is pushed down so as to approach the ground G.

[0038] As shown in FIG. 1, the handle unit 8 includes a lower frame 98, an upper frame 100, a right box 102, a left box 104, a main power switch 106, and an operating lever 108. The lower frame 98 has a substantially U-shape. The lower frame 98 extends rearward and upward from the housing 12. The main unit 4 includes a right handle bracket 110 and a left handle bracket 112 each having a plate shape. The right front end of the lower frame 98 is attached to the right surface of the housing 12 via the right handle bracket 110. The left front end of the lower frame 98 is attached to the left surface of the housing 12 via the left handle bracket 112. The right handle bracket 110 and the left handle bracket 112 connect the lower frame 98 and the housing 12.

[0039] As shown in FIG. 3, the right handle bracket 110 is fixed to the upper housing 26 and the lower housing 28. In the left-right direction, the right handle bracket 110 is disposed opposite the first communication port 40. When the lawn mower 2 is viewed from the right side to the left side, the right handle bracket 110 at least partially overlaps with the first communication port 40. The right handle bracket 110 covers the first communication port 40 from the right side. As shown in FIG. 10, in the left-right direction, the right handle bracket 110 is disposed between the right front wheel 60 and the first communication port 40. In the up-down direction, the lower end of the right handle bracket 110 is disposed below the lower end of the first communication port 40, and the upper end of the right handle bracket 110 is disposed above the upper end of the first communication port 40. Therefore, for example, when the right front wheel 60 is washed with liquid, the liquid hits the right handle bracket 110, and the right handle bracket 110 prevents the liquid from entering the internal space 30 of the housing 12 through the first communication port 40. Furthermore, since the first water drainage hole 42 is disposed below the first communication port 40, even if the liquid enters the internal space 30, the liquid is discharged from the internal space 30 through the first water drainage hole 42. Furthermore, since the first water drainage hole 42 is disposed opposite the right front wheel 60 in the left-right direction, for example, when the right front wheel 60 is washed with liquid, the liquid is prevented from entering the internal space 30 of the housing 12 through the first water drainage hole 42.

[0040] As shown in Fig. 1, the upper frame 100 has a generally U-shape. The right and left front ends of the upper frame 100 are fixed to the upper rear part of the lower frame 98 so as to sandwich the lower frame 98 in the left-right direction. The upper frame 100 is provided with a grip portion 114 extending in the left-right direction. The grip portion 114 is held by the user.

[0041] The right box 102 is fixed to the upper frame 100 on the right side and below the grip portion 114. The left box 104 is fixed to the upper frame 100 on the left side and below the grip portion 114. A main power switch 106 is disposed on the right box 102. When pressed by a user, the main power switch 106 switches the turf management machine 2 between an on state and an off state. An operating lever 108 is supported by the right box 102 and the left box 104 so as to be rotatable about a rotation axis extending in the left-right direction. When the turf management machine 2 is in the on state, pulling the operating lever 108 in a direction toward the grip portion 114 operates an electric motor 122 (see FIG. 11), which will be described later.

[0042] 11, the main unit 4 further includes a sponge member 118, a control unit 120, an electric motor 122, a motor housing 124, a fan 126, a transmission unit 128 (see FIG. 13), and a cutter unit 130 (see FIG. 13). The sponge member 118, the control unit 120, the electric motor 122, the motor housing 124, the fan 126, and the transmission unit 128 are accommodated in the internal space 30 of the housing 12.

[0043] The internal space 30 includes a first internal space 134, a second internal space 136, and a third internal space 138. The first internal space 134 is disposed forward of the first communication port 40 (see FIG. 10). As shown in FIG. 12, the first internal space 134 communicates with the outside of the lawn care machine 2 via the second communication port 44 and the second drainage hole 46. As shown in FIG. 11, the second internal space 136 is disposed rearward of the first internal space 134. The second internal space 136 communicates with the first internal space 134 via a first connection opening 140. The third internal space 138 is disposed to the right of the second internal space 136. The third internal space 138 communicates with the second internal space 136 via a second connection opening 142. 10, the third internal space 138 communicates with the outside of the turf management machine 2 via the first communication port 40 and the first drainage hole 42. The third internal space 138 is located to the left of the first communication port 40 and the first drainage hole 42.

[0044] As shown in FIG. 12, the sponge member 118 is disposed in the first internal space 134. The sponge member 118 is made of a porous material. Air can pass through the sponge member 118. Meanwhile, foreign matter such as dust cannot pass through the sponge member 118. The sponge member 118 is disposed below the connection point between the upper housing 26 and the lower housing 28 (i.e., on the ground G side). The lower housing 28 includes a waterproof wall 144 that protrudes upward rearward from the second drainage hole 46, and the sponge member 118 is disposed forward from the waterproof wall 144. The sponge member 118 is disposed adjacent to the rear side of the second communication port 44. In the front-rear direction, the sponge member 118 is disposed between the second communication port 44 and the waterproof wall 144. The sponge member 118 is disposed adjacent to the upper side of the second drainage hole 46. The sponge member 118 guides liquid (for example, liquid that has entered through the second communication port 44) to the second drainage hole 46. This allows the liquid to be discharged to the outside of the lawn management machine 2 via the second drainage hole 46.

[0045] The control unit 120 is disposed in the first internal space 134. The control unit 120 controls the electric motor 122 in response to the operation of the operating lever 108 (see FIG. 1). The control unit 120 is disposed behind the sponge member 118 and the waterproof wall 144. The control unit 120 includes a board 148 having a microcomputer and a plurality of switching elements (not shown). The board 148 has a plate shape. The board 148 is disposed so that a bottom surface 150 is perpendicular to the front-rear direction. The bottom surface 150 is aligned in the up-down direction and the left-right direction.

[0046] As shown in FIG. 11, the electric motor 122 and the motor housing 124 are inserted into the second connection opening 142. The electric motor 122 and the motor housing 124 are disposed on the rear side of the control unit 120. The electric motor 122 is, for example, a DC brushless motor. In a modified example, the electric motor 122 may be an AC motor or a brushed motor. The electric motor 122 includes a motor shaft 152. In the front-rear direction, the position of the motor shaft 152 is substantially the same as the position of the front end of the first communication port 40. In FIG. 11, the first communication port 40 is illustrated by a dashed line. When power is supplied from the battery pack BP (see FIG. 5) to the electric motor 122, the motor shaft 152 rotates around a rotation axis AX4 extending in the left-right direction.

[0047] The motor housing 124 includes a motor support portion 154 and a cover portion 156. The motor support portion 154 and the cover portion 156 define an accommodation space 158 that accommodates the electric motor 122 and the fan 126. The motor support portion 154 is fixed to the housing 12. The motor support portion 154 is inserted into the second connection opening 142. The motor support portion 154 supports the electric motor 122. The motor support portion 154 has a substantially cylindrical shape having a bottom portion 160. The motor support portion 154 has an intake opening 162 that penetrates the bottom portion 160. The intake opening 162 communicates between the second internal space 136 and the accommodation space 158. The cover portion 156 is disposed on the right side of the motor support portion 154. The cover portion 156 is fixed to the motor support portion 154 and also to the housing 12. The motor shaft 152 is inserted into the cover portion 156, and the cover portion 156 rotatably supports the motor shaft 152. Note that in Fig. 11, the motor shaft 152 is illustrated by a dashed line. The cover portion 156 covers the right end opening of the motor support portion 154. The cover portion 156 has an exhaust opening 164 that penetrates the cover portion 156. The exhaust opening 164 communicates between the accommodation space 158 and the third internal space 138.

[0048] The fan 126 is disposed on the right side of the electric motor 122. The fan 126 is fixed to the motor shaft 152. The fan 126 is, for example, a centrifugal fan. The fan 126 rotates together with the motor shaft 152. This generates an airflow AF in the internal space 30. Specifically, as shown in FIG. 12, air passes through the second communication port 44 and flows from the outside of the lawn care machine 2 into the first internal space 134. The air that has flowed in passes through the sponge member 118. As a result, foreign matter that has flowed into the first internal space 134 together with the air is captured by the sponge member 118. Next, the air flows upward along the control unit 120, and then bends and flows toward the first connection opening 140. This cools the control unit 120. Next, the air flows from the first internal space 134 into the second internal space 136 through the first connection opening 140. As shown in FIG. 11, the incoming air passes through the intake opening 162 and flows from the second internal space 136 into the storage space 158. The air then passes through the inside and outside of the electric motor 122, thereby cooling the electric motor 122. The air is then sent to the fan 126 and passes through the exhaust opening 164 and flows from the storage space 158 into the third internal space 138. The incoming air flows to the right, then bends and flows backward. As shown in FIG. 10, the air passes through the first communication port 40 and then flows between the lower housing 28 and the right handle bracket 110, and flows out to the outside of the lawn care machine 2.

[0049] The transmission unit 128 is disposed in the third internal space 138. The transmission unit 128 is disposed on the left side of the first communication port 40. The transmission unit 128 is disposed in a position facing the first communication port 40 in the left-right direction. As shown in FIG. 13, the transmission unit 128 includes a first pulley 168, a second pulley 170, a belt 172, and an output shaft 174. The first pulley 168 is fixed to the motor shaft 152. The second pulley 170 is disposed rearward of the first pulley 168. The diameter of the outer circumferential surface of the second pulley 170 is larger than the diameter of the outer circumferential surface of the first pulley 168. The belt 172 is stretched between the first pulley 168 and the second pulley 170. When the first pulley 168 rotates, the belt 172 rotates around the first pulley 168 and the second pulley 170, causing the second pulley 170 to rotate. The rotation speed of the second pulley 170 is smaller than the rotation speed of the first pulley 168. The first pulley 168, the second pulley 170, and the belt 172 function as a reducer. The output shaft 174 is fixed to the second pulley 170. The output shaft 174 rotates together with the second pulley 170. As shown in FIG. 14, the output shaft 174 is inserted into a mounting unit 178, which will be described later. The output shaft 174 is engaged with the cutter unit 130.

[0050] The main unit 4 includes an attachment unit 178, and the cutter unit 130 is attached to the attachment unit 178. The attachment unit 178 is fixed to the lower housing 28 inside the lower housing 28. The attachment unit 178 is disposed at the rear lower part of the lower housing 28.

[0051] As shown in FIG. 15, the mounting unit 178 includes a right support member 180, a right bearing 182 (see FIG. 16), a left support member 184, a left bearing 186 (see FIG. 16), a connecting shaft 188, a right fixing screw 190, and a left fixing screw 192. The right support member 180 includes a transmission unit facing portion 194 and an upper protruding wall portion 196. As shown in FIG. 14, the transmission unit facing portion 194 faces the transmission unit 128 in the left-right direction. As shown in FIG. 16, the transmission unit facing portion 194 has a longitudinal direction in the front-rear direction. The left front portion of the transmission unit facing portion 194 is formed by the cover portion 156. The transmission unit facing portion 194 has a through hole 194a penetrating the transmission unit facing portion 194 in the left-right direction. The through hole 194a is located in the rear lower portion of the transmission unit facing portion 194. The transmission unit facing portion 194 supports the right bearing 182 in the through hole 194a. The output shaft 174 is inserted into the through hole 194a, and the right bearing 182 rotatably supports the output shaft 174. The upper protruding wall portion 196 protrudes upward from the rear upper portion of the transmission unit facing portion 194. The upper protruding wall portion 196 is disposed above the through hole 194a. The upper protruding wall portion 196 has a right shaft insertion opening 198 and a right screw insertion opening 200. The right shaft insertion opening 198 penetrates the upper protruding wall portion 196 in the left-right direction. The right shaft insertion opening 198 is located at the top of the upper protruding wall portion 196. The right screw insertion opening 200 is disposed above the right shaft insertion opening 198. The right screw insertion opening 200 extends in the up-down direction. The lower end of the right screw insertion opening 200 is connected to the right shaft insertion opening 198. The upper end of the right screw insertion opening 200 is open. As shown in Fig. 17, the cross section of the right shaft insertion opening 198 has a substantially circular shape. The cross section of the right screw insertion opening 200 also has a substantially circular shape.

[0052] The right support member 180 further includes a right rib portion 202 that protrudes leftward from the right surface of the upper protruding wall portion 196. The right rib portion 202 is disposed in the vicinity of the right shaft insertion opening 198. The right rib portion 202 includes a front portion 204, a rear portion 206, and a lower portion 208. The front portion 204 extends in the up-down direction. The front portion 204 is disposed forward of the right shaft insertion opening 198. The rear portion 206 extends in the up-down direction. The rear portion 206 is disposed rearward of the front portion 204 and the right shaft insertion opening 198. The lower portion 208 extends in the front-rear direction. The lower portion 208 is connected to the lower end of the front portion 204 and the lower end of the rear portion 206. The lower portion 208 blocks the vicinity of the lower end of the right shaft insertion opening 198 from the right side. The lower portion 208 is provided with a right abutment surface 210 having a planar shape along the front-rear and left-right directions. The right abutment surface 210 is located on the upper surface of the lower portion 208. The right abutment surface 210 is adjacent to the right shaft insertion opening 198. In the up-down direction, the right abutment surface 210 is located between the upper end and the lower end of the right shaft insertion opening 198.

[0053] As shown in FIG. 16, the left support member 184 is disposed on the left side of the right support member 180. The left support member 184 has a longitudinal direction in the up-down direction. The left support member 184 includes a left bearing fixing portion 214 recessed from the right surface of the left support member 184. The left bearing fixing portion 214 is disposed at a position facing the through hole 194a in the left-right direction. The left support member 184 supports a left bearing 186 in the left bearing fixing portion 214. The left bearing 186 rotatably supports the cutter unit 130 (see FIG. 14). The left support member 184 has a left shaft insertion opening 216 and a left screw insertion opening 218. The left shaft insertion opening 216 extends leftward from the right surface of the left support member 184. The left shaft insertion opening 216 is located at the upper portion of the left support member 184. The left shaft insertion opening 216 is disposed at a position facing the right shaft insertion opening 198 in the left-right direction. The left screw insertion opening 218 is disposed above the left shaft insertion opening 216. The left screw insertion opening 218 extends in the up-down direction. The lower end of the left screw insertion opening 218 is connected to the left shaft insertion opening 216. The upper end of the left screw insertion opening 218 is open. As shown in FIG. 18 , the cross section of the left shaft insertion opening 216 has a substantially circular shape. In addition, the cross section of the left screw insertion opening 218 has a substantially circular shape.

[0054] The left support member 184 has a recess 220 recessed from the left surface of the left support member 184. The recess 220 is located at the upper end of the left support member 184. The recess 220 is connected to the upper surface of the left support member 184. The recess 220 is connected to the left end of the left shaft insertion opening 216. The recess 220 has a left abutment surface 222 having a planar shape along the front-rear direction and the left-right direction. The left abutment surface 222 is located at the bottom surface of the recess 220. The left abutment surface 222 is adjacent to the left shaft insertion opening 216. In the up-down direction, the left abutment surface 222 is located between the upper end and the lower end of the left shaft insertion opening 216.

[0055] As shown in FIG. 15, the connection shaft 188 connects the right support member 180 and the left support member 184. The connection shaft 188 extends in the left-right direction. The connection shaft 188 has an elongated, generally cylindrical shape. As shown in FIG. 17, the connection shaft 188 has a right cutout portion 224 located at the right end of the connection shaft 188. The right cutout portion 224 is recessed leftward from the right end face of the connection shaft 188 and is recessed upward from the lower end of the outer circumferential surface of the connection shaft 188. The right cutout portion 224 has a right alignment surface 226 extending in the left-right direction. The right alignment surface 226 has a planar shape along the left-right direction and the front-rear direction. As shown in FIG. 18, the connection shaft 188 has a left cutout portion 228 located at the left end of the connection shaft 188. The left cutout 228 is recessed rightward from the left end face of the connecting shaft 188, and is recessed upward from the lower end of the outer circumferential surface of the connecting shaft 188. The left cutout 228 is provided with a left alignment surface 230 that extends in the left-right direction. The left alignment surface 230 has a planar shape that is aligned in the left-right direction and the front-rear direction.

[0056] Next, a method of fixing the connecting shaft 188 to the right support member 180 and the left support member 184 will be described. First, the left end of the connecting shaft 188 is inserted into the left shaft insertion opening 216 of the left support member 184 with the left alignment surface 230 of the connecting shaft 188 facing downward. As a result, the left alignment surface 230 abuts against the left abutment surface 222 of the left support member 184. Next, as shown in FIG. 17, the right end of the connecting shaft 188 is inserted into the right shaft insertion opening 198 of the right support member 180 with the right alignment surface 226 of the connecting shaft 188 facing downward. As a result, the right alignment surface 226 abuts against the right abutment surface 210 of the right support member 180. Next, in a state where the connecting shaft 188 is pressed downward (i.e., in a state where the right-side positioning surface 226 is pressed against the right-side abutment surface 210), the right-side fixing screw 190 is inserted from above into the right-side screw insertion opening 200, and the right end of the connecting shaft 188 is fixed to the right-side support member 180 by the right-side fixing screw 190. Finally, as shown in FIG. 18, in a state where the connecting shaft 188 is pressed downward (i.e., in a state where the left-side positioning surface 230 is pressed against the left-side abutment surface 222), the left-side fixing screw 192 is inserted from above into the left-side screw insertion opening 218, and the left end of the connecting shaft 188 is fixed to the left-side support member 184 by the left-side fixing screw 192. As a result, as shown in FIG. 16, the central axis of the right-side bearing 182 and the central axis of the left-side bearing 186 are arranged on the same straight line. As a result, it is possible to suppress vibrations caused by the rotation of the cutter unit 130, compared to a configuration in which the central axes of the right-side bearing 182 and the left-side bearing 186 are not arranged on the same straight line.

[0057] As shown in FIG. 14, the right end of the cutter unit 130 is attached to the right support member 180 via the output shaft 174. The left end of the cutter unit 130 is attached to the left support member 184 via the left bearing 186. The cutter unit 130 is attached to the housing 12 via the mounting unit 178. When the output shaft 174 rotates, the cutter unit 130 rotates around a rotation axis AX5 extending in the left-right direction. This allows thatching, aeration, and cutting to be performed. The rotation speed of the cutter unit 130 is, for example, 3200 rpm or more, and preferably 2100 rpm or more and 3800 rpm or less.

[0058] As shown in FIG. 19, when the lawn care machine 2 is viewed from the left side along the rotation axis AX2 of the right front wheel 60 and the left front wheel 62 (see FIG. 20), the right front wheel 60 and the left front wheel 62 at least partially overlap in the left-right direction with the battery mounting unit 16, the battery pack BP, the control unit 120, the electric motor 122, and the fan 126 (see FIG. 20). When the lawn care machine 2 is viewed from the left side along the rotation axis AX2, the battery mounting unit 16 and the battery pack BP at least partially overlap in the left-right direction with the electric motor 122 and the fan 126. The battery mounting unit 16 and the battery pack BP are disposed above the motor shaft 152 of the electric motor 122. The rotation axis AX4 of the motor shaft 152 is disposed above the rotation axis AX2 of the right front wheel 60 and the left front wheel 62 (see FIG. 20) and the rotation axis AX5 of the cutter unit 130. The control unit 120 is disposed forward of the pivot axis AX1 and the rotation axis AX2. Furthermore, the control unit 120 is disposed forward of the battery mounting unit 16, the battery pack BP, the electric motor 122, the fan 126 (see FIG. 20), and the cutter unit 130. The rotation axis AX5 of the cutter unit 130 is disposed rearward of the battery mounting unit 16, the battery pack BP, the right front wheel 60, the left front wheel 62, the electric motor 122, and the fan 126 (see FIG. 20).

[0059] As shown in Figure 20, the battery mounting unit 16 and the battery pack BP are positioned to the left of the electric motor 122. When the lawn cultivation machine 2 is viewed from the rear in the front-to-rear direction perpendicular to the rotation axis AX2, the control unit 120 overlaps in its entirety with the electric motor 122 and the entire fan 126 in the front-to-rear direction, and at least partially overlaps in the front-to-rear direction with the vicinity of the right end of the cutter unit 130. When the lawn cultivation machine 2 is viewed from the rear in the front-to-rear direction, the electric motor 122 at least partially overlaps in the front-to-rear direction with the vicinity of the right end of the cutter unit 130.

[0060] 21, when the lawn trimmer 2 is viewed from above along the vertical direction perpendicular to the rotation axis AX2, the central shaft portion 64 of the front wheel unit 22 at least partially overlaps in the vertical direction with the battery pack BP, the electric motor 122, and the fan 126. The control unit 120 is disposed forward of the central shaft portion 64.

[0061] As shown in FIG. 22, the cutter unit 130 includes a shaft 232, a plurality of cutter blades 234 (16 in this embodiment), a plurality of long spacers 236 (15 in this embodiment), a fixing pin 238, a short spacer 240, and a fixing nut 242.

[0062] As shown in FIG. 23, the shaft 232 includes a first portion 246 and a second portion 248. The first portion 246 extends in the left-right direction. The outer peripheral surface of the first portion 246 has a polygonal cross-sectional shape, which is a substantially square cross-sectional shape in this embodiment. As shown in FIG. 14, the right end of the first portion 246 engages with the output shaft 174. As shown in FIG. 23, the second portion 248 is disposed on the left side of the first portion 246. The outer peripheral surface of the second portion 248 has a substantially circular cross-sectional shape. As shown in FIG. 14, the left end of the second portion 248 is attached to the left support member 184 via the left bearing 186.

[0063] As shown in FIG. 22, the cutter blades 234 are arranged in the first portion 246. The cutter blades 234 are aligned in the left-right direction. The number of the cutter blades 234 is an even number. The cutter blades 234 are made of, for example, a metal material. In a modified example, the cutter blades 234 may be made of a resin material. The cutter blades 234 have a flat plate shape. In a modified example, the cutter blades 234 may have a curved plate shape. The weight of the cutter blade 234 is, for example, 2000 g or less, and preferably 1000 g or more and 3000 g or less.

[0064] As shown in FIG. 24, the cutter blade 234 includes a cutter portion 252 and an attachment portion 254. The cutter portion 252 extends in a direction away from the shaft 232. The cutter portion 252 extends in a substantially linear manner. The cutter portion 252 performs thatching, aeration, and cutting. The attachment portion 254 is connected to the cutter portion 252. The attachment portion 254 has an attachment opening 256 penetrating the attachment portion 254 in the thickness direction (left-right direction). The attachment opening 256 has a polygonal cross-sectional shape, and in this embodiment, a substantially square cross-sectional shape. The cross-sectional shape of the attachment opening 256 is the same as the cross-sectional shape of the outer circumferential surface of the first portion 246. The first portion 246 is inserted into the attachment opening 256. When the first portion 246 is inserted into the attachment opening 256, each face of the outer circumferential surface of the first portion 246 faces each face of the attachment opening 256. This can prevent the cutter blade 234 from rotating around the first portion 246. Moreover, in the cutter blade 234 of this embodiment, the attachment portion 254 is designed to be relatively large. This can reduce the difference in weight between the portion of the cutter blade 234 on the cutter portion 252 side with respect to the attachment opening 256 and the portion of the cutter blade 234 on the opposite side to the cutter portion 252 with respect to the attachment opening 256. This can prevent the balance of the cutter blade 234 itself from becoming worse.

[0065] By changing the positional relationship between the respective faces of the outer circumferential surface of the first portion 246 and the respective faces of the mounting opening 256, the posture of the cutter blade 234 with respect to the first portion 246 changes. The mounting opening 256 has a face 256a that is closest to the cutter portion 252 among the respective faces of the mounting opening 256. When the face 256a of the mounting opening 256 faces the upper face 246a of the outer circumferential surface of the first portion 246, the cutter blade 234 has a first posture in which the cutter portion 252 extends upward from the first portion 246. When the face 256a of the mounting opening 256 faces the rear face 246b of the outer circumferential surface of the first portion 246, the cutter blade 234 has a second posture in which the cutter portion 252 extends rearward from the first portion 246. Furthermore, when the surface 256a of the mounting opening 256 faces the lower surface 246c of the outer circumferential surface of the first portion 246, the cutter blade 234 has a third posture in which the cutter portion 252 extends downward from the first portion 246. When the surface 256a of the mounting opening 256 faces the front surface 246d of the outer circumferential surface of the first portion 246, the cutter blade 234 has a fourth posture in which the cutter portion 252 extends forward from the first portion 246. In the circumferential direction of the rotation axis AX5, when the position of the cutter portion 252 in the first posture is set to 0 degrees, the cutter portion 252 in the second posture is located at a position of 90 degrees, the cutter portion 252 in the third posture is located at a position of 180 degrees, and the cutter portion 252 in the fourth posture is located at a position of 270 degrees. The cutter portions 252 in each posture are disposed at equal intervals in the circumferential direction of the rotation axis AX5. In addition, the spacing between the cutter portions 252 in each position in the circumferential direction (90 degrees in this embodiment) is approximately the same as the value obtained by dividing 360 degrees by the number of faces on the outer circumferential surface of the first portion 246 (4 in this embodiment).

[0066] 22, the multiple long spacers 236 are inserted into the first portion 246. The long spacers 236 have a substantially cylindrical shape. The long spacers 236 are sandwiched between adjacent cutter blades 234 in the left-right direction. As a result, the multiple cutter blades 234 are arranged at equal intervals in the left-right direction.

[0067] The fixed pin 238 is disposed near the right end of the first portion 246. The fixed pin 238 is inserted into the first portion 246 so as to be approximately perpendicular to the rotation axis AX5. The fixed pin 238 abuts against the rightmost cutter blade 234 from the right side. The fixed pin 238 prevents the cutter blade 234 from moving rightward beyond the fixed pin 238. The fixed pin 238 abuts against the output shaft 174 from the left side. The fixed pin 238 prevents the rightmost cutter blade 234 from abutting against the output shaft 174.

[0068] The short spacer 240 is disposed near the left end of the first portion 246. The shaft 232 is inserted into the short spacer 240. The short spacer 240 has a substantially cylindrical shape. The short spacer 240 abuts against the leftmost cutter blade 234 from the left side.

[0069] The fixing nut 242 is fixed to the second portion 248. The fixing nut 242 abuts against the short spacer 240 from the left side. In the left-right direction, the multiple cutter blades 234, the multiple long spacers 236, and the short spacer 240 are sandwiched between the fixing pin 238 and the fixing nut 242. This fixes the left-right positions of the multiple cutter blades 234, the multiple long spacers 236, and the short spacer 240 relative to the shaft 232.

[0070] The left-right positions and attitudes of the multiple cutter blades 234 will be described. In the following description, the center in the left-right direction between the rightmost cutter blade 234 and the leftmost cutter blade 234 is defined as a center position CP. As shown in FIG. 25, the center position CP is located at the center in the left-right direction between the eighth cutter blade 234 from the right and the ninth cutter blade 234 from the right. No cutter blade 234 is located at the center position CP. The number of cutter blades 234 (8 in this embodiment) located to the right of the center position CP is the same as the number of cutter blades 234 (8 in this embodiment) located to the right of the center position CP.

[0071] The attachment position of the cutter blade 234 arranged on the right side of the center position CP to the shaft 232 is approximately the same as the attachment position of the cutter blade 234 arranged on the left side of the center position CP to the shaft 232. The left-right arrangement of the eight cutter blades 234 when viewed to the right from the center position CP is approximately the same as the left-right arrangement of the eight cutter blades 234 when viewed to the left from the center position CP. In other words, the distance between the center position CP and the Nth cutter blade 234 to the right of the center position CP is approximately the same as the distance between the center position CP and the Nth cutter blade 234 to the left of the center position CP.

[0072] 22, the postures of the multiple cutter blades 234 change in sequence from the center position CP to the right in accordance with a cycle of the fourth posture, the second posture, the third posture, and the first posture. Also, the postures of the multiple cutter blades 234 change in sequence from the center position CP to the left in accordance with a cycle of the fourth posture, the second posture, the third posture, and the first posture. The posture of the cutter blade 234 located Nth to the right of the center position CP is the same as the posture of the cutter blade 234 located Nth to the left of the center position CP. That is, the postures of two cutter blades 234 located at the same distance from the center position CP in the left-right direction are the same.

[0073] (effect) The lawn care machine 2 of this embodiment performs maintenance on the lawn on the ground G while moving forward on the ground G. The lawn care machine 2 includes a right front wheel 60 and a left front wheel 62 (an example of a pair of wheels) that rotate on the ground G, a handle unit 8 that is held by a user when the lawn care machine 2 is moving, a cutter unit 130 (an example of a working unit) that works on the ground G, an electric motor 122 that drives the cutter unit 130, a fan 126 that rotates when driven by the electric motor 122, a housing 12 that supports the cutter unit 130 and accommodates the electric motor 122 and the fan 126, and a right handle bracket 110 (an example of a wall body) that is disposed outside the housing 12 and attached to the housing 12. The housing 12 communicates between the inside and outside of the housing 12 and has a first communication opening 48 (an example of a communication opening) through which air passes as the fan 126 rotates. The right handle bracket 110 is disposed opposite the first communication opening 48.

[0074] According to the above configuration, when the lawn care machine 2 is being washed with liquid, the liquid hits the right handle bracket 110, thereby preventing the liquid from reaching the first communication opening 48. This prevents the liquid from passing through the first communication opening 48 and flowing into the housing 12.

[0075] In addition, the right handle bracket 110 is disposed between the first communication opening 48 and the right front wheel 60.

[0076] When the lawn care machine 2 moves over the ground G, dirt and grass may adhere to the right front wheel 60. With the above configuration, even when the right front wheel 60 is washed with liquid, the liquid hits the right handle bracket 110, thereby preventing the liquid from reaching the first communication opening 48. This prevents the liquid from passing through the first communication opening 48 and flowing into the housing 12.

[0077] Further, a right handle bracket 110 (an example of a handle bracket) connects the handle unit 8 and the housing 12 together.

[0078] According to the above configuration, the handle unit 8 and the housing 12 can be connected with a single part, and liquid can be prevented from passing through the first communication opening 48 and flowing into the inside of the housing 12 when the lawn care machine 2 is being washed with liquid.

[0079] Furthermore, when the lawn mower 2 is viewed along the rotation axis AX2 of the right front wheel 60 and the left front wheel 62, the electric motor 122 at least partially overlaps the right front wheel 60.

[0080] According to the above configuration, the electric motor 122, which is a heavy object, is disposed near the ground G. This makes it possible to suppress the housing 12 from tilting with respect to the ground G when an external force acts on the housing 12, compared to a configuration in which the electric motor 122 is not disposed near the ground G.

[0081] The lawn cultivation machine 2 is further provided with a control unit 120 that is housed in the housing 12 and controls the electric motor 122. When the lawn cultivation machine 2 is viewed from the rear, the control unit 120 at least partially overlaps with the electric motor 122.

[0082] When the fan 126 rotates, air passes through the electric motor 122. According to the above configuration, the distance between the electric motor 122 and the control unit 120 can be shortened. This allows the control unit 120 to be more effectively cooled by the air passing through the electric motor 122.

[0083] In addition, the control unit 120 is disposed in front of the electric motor 122 .

[0084] According to the above configuration, the space behind the electric motor 122 can be made more compact than in a configuration in which the control unit 120 is disposed behind the electric motor 122. Therefore, for example, when the cutter unit 130 is disposed behind the electric motor 122, the distance between the electric motor 122 and the cutter unit 130 can be shortened.

[0085] The lawn cultivation machine 2 also includes a battery pack BP (an example of a battery) that supplies power to the electric motor 122. When the lawn cultivation machine 2 is viewed along the rotation axis AX2 of the right front wheel 60 and the left front wheel 62, the battery pack BP at least partially overlaps the electric motor 122.

[0086] According to the above configuration, the battery pack BP, which is a heavy object, is disposed near the ground G. This makes it possible to suppress the housing 12 from tilting with respect to the ground G when an external force acts on the housing 12, as compared to a configuration in which the battery pack BP is not disposed near the ground G.

[0087] The housing 12 may have a first drainage hole 42 (an example of a drainage hole) that is disposed closer to the ground G than the first communication opening 48 and communicates between the inside and the outside of the housing 12. The first drainage hole 42 is disposed at a position facing the right front wheel 60.

[0088] With the above configuration, even when liquid passes through the first communication opening 48 and flows into the housing 12, the liquid can be discharged to the outside of the housing 12 via the first drainage hole 42. Furthermore, when the lawn care machine 2 is being washed with liquid, the liquid hits the right front wheel 60, preventing the liquid from reaching the first drainage hole 42. This prevents the liquid from passing through the first drainage hole 42 and flowing into the housing 12.

[0089] (Modification) The lawn care machine 2 according to one embodiment may be a work machine equipped with a non-removable built-in battery. In this case, the built-in battery is charged by connecting the power cord to an external power source.

[0090] The turf management machine 2 according to one embodiment may include a power cord that can be connected to an external power source. In this case, the turf management machine 2 may be operated by power supplied from the external power source via the power cord.

[0091] In the lawn mower 2 according to one embodiment, the first communication port 40 may face a member other than the right handle bracket 110.

[0092] In one embodiment of the lawn management machine 2, when the fan 126 rotates, air flows into the interior of the housing 12 through the first communication port 40, then flows through the third internal space 138, the storage space 158, the second internal space 136, and the first internal space 134 in that order, and may be discharged to the outside of the housing 12 through the second communication port 44.

[0093] In the cutter unit 130 according to an embodiment, the structure for attaching the cutter blade 234 to the shaft 232 is not limited to the structure described in the embodiment. For example, the shaft 232 may have attachment parts arranged on each of the upper surface 246a, the rear surface 246b, the lower surface 246c, and the front surface 246d. The cutter blade 234 may be attachable to the attachment parts arranged on each of the upper surface 246a, the rear surface 246b, the lower surface 246c, and the front surface 246d.

[0094] In the cutter unit 130 according to one embodiment, the posture of the cutter blade 234 relative to the shaft 232 is not limited to four types, and may be, for example, three types, or five or more types. For example, the outer peripheral surface of the first portion 246 of the shaft 232 may have a triangular, pentagonal, hexagonal, or octagonal shape, and the cross-sectional shape of the mounting opening 256 of the cutter blade 234 may have a triangular, pentagonal, hexagonal, or octagonal shape. In addition, the outer peripheral surface of the first portion 246 may have a shape other than a polygonal shape, and the cross-sectional shape of the mounting opening 256 may have a shape other than a polygonal shape.

[0095] In the cutter unit 130 according to one embodiment, the cutter blades 234 arranged on the right side of the center position CP may not be arranged at equal intervals in the left-right direction. In this case, the cutter blades 234 arranged on the right side of the center position CP are not arranged at equal intervals in the left-right direction. [Explanation of symbols]

[0096] 2: Lawn management machine 4: Main unit 8: Handle unit 12: Housing 26: Upper housing 28: Lower housing 30: Interior space 40: First communication port 42: First drain hole 44: Second communication port 46: Second drain hole 48: 1st communication opening 50: 2nd communication opening 60: Right front wheel 62:Left front wheel 110: Right side handle bracket 112: Left handle bracket 120: Control unit 122: Electric motor 126: Fan 128: Transmission unit 130: Cutter unit 134: 1st internal space 136:Second internal space 138:Third internal space 152: Motor shaft 154: Motor support 174: Output shaft 178: Mounting unit 232: Shaft 234: Cutter blade 246 :1st part 246a:Top surface 246b: Rear 246c: Bottom surface 246d:Front 252: Cutter part 254: Mounting part 256: Installation opening AX1, AX3: Rotating axis AX2, AX4, AX5: Rotation axis BP: Battery pack CP : Central location G : Ground

Claims

1. A lawn care machine that performs maintenance on a lawn on the ground while moving forward on the ground, a pair of wheels that rotate on the ground; a handle unit that is gripped by a user when moving the lawn care machine; a working unit that works on the ground; an electric motor that drives the working unit; a fan that is rotated by being driven by the electric motor; a housing supporting the working unit and accommodating the electric motor and the fan; a wall disposed outside the housing and attached to the housing; the housing has a communication opening that communicates the inside and the outside of the housing and through which air passes as the fan rotates; The wall body is disposed opposite the communication opening.

2. The turf management machine according to claim 1 , wherein the wall is disposed between the communication opening and the wheel.

3. The turf management machine according to claim 1 , wherein the wall is a handle bracket that connects the handle unit and the housing.

4. The turf management machine of claim 1 , wherein the electric motor at least partially overlaps the wheels when the turf management machine is viewed along the rotational axis of the pair of wheels.

5. a control unit accommodated in the housing and controlling the electric motor; The turf management machine of claim 4 , wherein the control unit at least partially overlaps the electric motor when the turf management machine is viewed from the rear.

6. The turf management machine according to claim 5 , wherein the control unit is disposed forward of the electric motor.

7. The electric motor further includes a battery for supplying power thereto. The turf management machine of claim 4 , wherein the battery at least partially overlaps the electric motor when the turf management machine is viewed along the rotational axes of the pair of wheels.

8. the housing is disposed closer to the ground than the communication opening and has a drain hole communicating the inside and outside of the housing; The turf management machine according to claim 1 , wherein the drainage holes are arranged in positions opposite the wheels.

Images