Working implement

Abstract

To provide technique enabling suppression of such a problem that air having flowed out from an exhaust port impinges against a user .SOLUTION: A working implement works while moving on the ground. The working implement comprises: an electric motor; a fan rotated by driving the electric motor; a housing unit housing the electric motor and the fan; a working unit which is rotated around a rotation axis nearly parallel to a virtual ground orthogonal to a vertical direction by driving the electric motor, and which works on the ground; and an axis changing unit transmitting the rotation of the electric motor to the working unit, and changing the direction of the rotation axis of the working unit to a direction different from the direction of a rotation axis of the electric motor. The housing unit comprises: an intake port through which air flows to the inside from the outside of the housing unit by rotating the fan; and an exhaust port through which air sent by the fan flows to the outside from the inside of the housing unit. The exhaust port communicates with a space on the side of the working unit.SELECTED DRAWING: Figure 13

Description

[Technical field]

[0001] The technology disclosed in this specification relates to a work machine. [Background technology]

[0002] Patent Document 1 discloses a working machine. The working machine includes an electric motor, a fan that rotates when driven by the electric motor, a housing unit that houses the electric motor and the fan, a working unit that rotates around a rotation axis that is approximately parallel to a virtual ground surface perpendicular to the up-down direction when driven by the electric motor, and an axis changing unit that transmits the rotation of the electric motor to the working unit and changes the direction of the rotation axis of the working unit to a direction different from the direction of the rotation axis of the electric motor. The housing unit has an intake port through which air flows from the outside of the housing unit to the inside as the fan rotates, and an exhaust port through which air sent out by the fan flows from the inside of the housing unit to the outside. The exhaust port faces a user who operates the working machine. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-141992 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned work machine, air flowing out from the exhaust port hits the user. This specification discloses a technique that can prevent the air flowing out from the exhaust port from hitting the user. [Means for solving the problem]

[0005] This specification discloses a working machine. The working machine works while moving on the ground. The working machine includes an electric motor, a fan that rotates when driven by the electric motor, a housing unit that houses the electric motor and the fan, a working unit that rotates about a rotation axis that is approximately parallel to a virtual ground perpendicular to the up-down direction when driven by the electric motor and works on the ground, and an axis changing unit that transmits the rotation of the electric motor to the working unit and changes the direction of the rotation axis of the working unit to a direction different from the direction of the rotation axis of the electric motor. The housing unit has an intake port through which air flows from the outside of the housing unit to the inside by the rotation of the fan, and an exhaust port through which air sent out by the fan flows from the inside of the housing unit to the outside. The exhaust port is connected to a space on the working unit side.

[0006] According to the above configuration, the air flowing out from the exhaust port flows toward the working unit and hits the ground, thereby preventing the air flowing out from the exhaust port from hitting the user. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a perspective view of a working machine 2 according to an embodiment. [Diagram 2] FIG. 2 is a side view of the working machine 2 of the embodiment. [Diagram 3] 2 is a perspective view of the working machine 2 of the embodiment when the handle unit 6 is in a folded position. FIG. [Figure 4] 2 is a front view of the vicinity of a right grip 38 in the working machine 2 of the embodiment. [Diagram 5] FIG. 2 is an exploded perspective view of a transmission case unit 58 according to the embodiment. [Figure 6] 1 is an exploded perspective view of a main body housing 94, a cover 96, and a fender 98 of the embodiment. [Figure 7] FIG. 2 is a perspective view of a main body housing 94 and a cover 96 of the embodiment. [Figure 8] 2 is a perspective view of the working machine 2 according to the embodiment when the cover 96 is in an open position. FIG. [Figure 9]2 is a cross-sectional view of the vicinity of a battery mounting unit 62 in the working machine 2 of the embodiment. [Figure 10] 2 is a cross-sectional view of the vicinity of a fan 204 in a state where a first transmission case 76 and a front handle 80 are removed in a main unit 8 of the embodiment. [Figure 11] FIG. 1 is a top view of the lower body housing 102 of the embodiment. [Figure 12] FIG. 2 is a perspective view of the lower body housing 102 of the embodiment. [Figure 13] 2 is a cross-sectional view of the vicinity of an exhaust port 184 in the working machine 2 of the embodiment. [Figure 14] 1 is a cross-sectional view of a working unit 10 and its surroundings in a working machine 2 of the embodiment. [Figure 15] 1 is an exploded perspective view of the main body unit 8 of the embodiment with a transmission case unit 58 and a lower main body housing 102 removed. FIG. [Figure 16] FIG. 2 is an exploded perspective view of a transmission unit 202 and a fan 204 according to the embodiment. [Figure 17] FIG. 2 is a perspective view of an operational unit 10 and a transmission unit 202 according to the embodiment. [Figure 18] 2 is a front view showing the positional relationship between the battery pack BP, the working unit 10, the battery mounting unit 62, the fan 204, and the motor case 208 in the embodiment. FIG. [Figure 19] 1 is a top view showing the positional relationship between the battery pack BP, the working unit 10, and the motor case 208 in the embodiment. FIG. [Figure 20] 2 is a left side view showing the positional relationship of the battery pack BP, the working unit 10, the battery mounting unit 62, the control unit 196, the fan 204, and the motor case 208 in the embodiment. FIG. [Figure 21] FIG. 2 is a perspective view of a lawnmower 400 according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Representative and non-limiting examples 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 the 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 working machines.

[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 housing unit may include a partition disposed between the electric motor and the working unit.

[0012] According to the above configuration, the space on the electric motor side and the space on the working unit side can be separated by a simple configuration of providing a partition wall.

[0013] In one or more embodiments, the exhaust port may be located on the working unit side relative to the bulkhead.

[0014] According to the above configuration, the partition can prevent the air flowing out of the exhaust port from flowing from the space on the working unit side to the space on the electric motor side, thereby further preventing the air flowing out of the exhaust port from hitting the user.

[0015] In one or more embodiments, the air intake may be located on the electric motor side relative to the bulkhead.

[0016] Sand and dust from the ground may be scattered in the space on the working unit side. With the above-mentioned configuration, it is possible to prevent the sand and dust from flowing into the inside of the housing unit through the air intake port.

[0017] In one or more embodiments, the housing unit may include a main housing that houses the electric motor and the fan. The main housing may be separate from the bulkhead.

[0018] According to the above configuration, the partition can be easily replaced depending on the configuration of the working unit.

[0019] In one or more embodiments, the main body housing may include a first main body housing that houses the electric motor, and a second main body housing that is separate from the first main body housing and houses the fan.

[0020] According to the above configuration, the combination of the electric motor and the fan can be easily changed.

[0021] In one or more embodiments, the air intake may open downwards.

[0022] According to the above configuration, it is possible to prevent liquid such as rainwater from flowing into the inside of the housing unit through the air intake port.

[0023] In one or more embodiments, when the fan rotates, air may flow from the air inlet to the air outlet within the housing unit. The working machine may be disposed between the air inlet and the electric motor in the air flow direction and may include a control unit for controlling the electric motor.

[0024] According to the above configuration, the cooling performance of the control unit can be improved.

[0025] In one or more embodiments, the fan may be a centrifugal fan.

[0026] According to the above configuration, the flow rate of air sent out from the fan can be increased.

[0027] In one or more embodiments, the working machine may further include a handle unit that is gripped by a user. The working machine may be a push-type working machine that is moved by a user pushing the handle unit forward.

[0028] In a push-type working machine, a user stands behind the working machine to operate the working machine. With the above configuration, even when the user is standing behind the working machine, it is possible to prevent the air flowing out from the exhaust port from hitting the user.

[0029] (Example) As shown in FIG. 1, the working machine 2 is a hand-pushed tiller. The working machine 2 is an electric working machine that operates with the power of a battery pack BP (see FIG. 8). The working machine 2 can till the soil with working claws 286, 294 described later. The working machine 2 can also pull out weeds. Furthermore, the working machine 2 can pile up the tilled soil to make ridges and break the ridges. That is, the working machine 2 is a soil management machine. With the working machine 2 placed on the ground P (see FIG. 2) in a working posture, the user stands behind the working machine 2 and pushes the working machine 2 forward to work. Hereinafter, the movement direction of the working machine 2 is referred to as the front-rear direction, the direction perpendicular to the front-rear direction is referred to as the left-right direction, and the direction perpendicular to the front-rear direction and the left-right direction is referred to as the up-down direction. The up-down direction is also perpendicular to a virtual ground P corresponding to a plane in which the height of the unevenness of the ground P is averaged. In this embodiment, the ground P and the virtual ground P are illustrated with the same line to make the drawing easier to see. The working machine 2 includes a frame unit 4, a handle unit 6, a main body unit 8, and a working unit 10.

[0030] As shown in FIG. 2, the frame unit 4 includes a pair of base plates 14, a frame pipe 16, a loop handle 18, a pair of arm plates 20, a biasing spring 22, a pair of wheels 24, and a resistance rod 26. The pair of base plates 14 are made of a metal material. The pair of base plates 14 are fixed to each other. The frame pipe 16 is made of a metal material. The frame pipe 16 is fixed to the pair of base plates 14. The frame pipe 16 extends toward the rear and upper side. The loop handle 18 is made of a metal material. The loop handle 18 is attached to the frame pipe 16. The pair of arm plates 20 are made of a metal material. The pair of arm plates 20 are fixed to each other. The pair of arm plates 20 are rotatably attached near the rear ends of the pair of base plates 14. The pair of arm plates 20 are rotatable between a lower position (see FIG. 1) and an upper position (see FIG. 2). The biasing spring 22 is attached to the base plate 14 and the arm plate 20. The biasing spring 22 biases the arm plate 20 to fix the arm plate 20 at the lower position or the upper position. The pair of wheels 24 are rotatably attached to the pair of arm plates 20. One wheel 24 is disposed on the left side of the pair of arm plates 20, and the other wheel 24 is disposed on the right side of the pair of arm plates 20. The rotating shaft of one wheel 24 is separate from the rotating shaft of the other wheel 24. Therefore, even if the pair of arm plates 20 rotates between the lower position and the upper position, the rotating shaft of the pair of wheels 24 does not interfere with the resistance rod 26. When the pair of arm plates 20 is in the lower position shown in FIG. 1, the pair of wheels 24 abuts on the ground P (see FIG. 2). The wheels 24 roll on the ground P, allowing the user to easily move the working machine 2. On the other hand, when the pair of arm plates 20 is in the upper position shown in Fig. 2, the pair of wheels 24 is separated from the ground P. The resistance rod 26 is made of a metal material. The resistance rod 26 has a bent shape that is bent near the center in the longitudinal direction. The resistance rod 26 is detachably attached to the rear ends of the pair of base plates 14.The resistance rod 26 can be attached to the rear ends of the pair of base plates 14 from above, and can also be attached to the rear ends of the pair of base plates 14 from below. This allows the orientation of the resistance rod 26 to be adjusted. The vertical position of the resistance rod 26 is adjusted so that the resistance rod 26 digs into the ground P when the pair of arm plates 20 are in the upper position and the pair of wheels 24 are away from the ground P. By having the resistance rod 26 dig into the ground P, it is possible to apply movement resistance to the work machine 2, and the tilling performance of the work machine 2 can be improved.

[0031] As shown in FIG. 1, the handle unit 6 is rotatably attached to the frame pipe 16. The handle unit 6 is rotatable between a working position (see FIG. 1) and a folding position (see FIG. 3). When the handle unit 6 is in the working position, it extends rearward and upward from the frame pipe 16. A user holds the handle unit 6 located in the working position and moves the working machine 2 to till the soil. As shown in FIG. 3, when the handle unit 6 is in the folding position, it is arranged so as to sandwich the main unit 8 in the left-right direction. When storing the working machine 2 or loading it into a vehicle, the user switches the handle unit 6 from the working position to the folding position. In this state, the user can easily lift the working machine 2 by holding the loop handle 18 and a front handle 80 described later.

[0032] As shown in FIG. 1, the handle unit 6 includes a pair of rotating plates 30, a handle pipe 32, a reinforcing pipe 34, a left grip 36, a right grip 38, a switch box unit 40, and a switch box guard 42. The pair of rotating plates 30 are made of a metal material. The pair of rotating plates 30 are fixed to each other. The pair of rotating plates 30 are rotatably attached to the rear end of the frame pipe 16. The handle pipe 32 is made of a metal material. The handle pipe 32 is fixed to the pair of rotating plates 30. The handle pipe 32 has a substantially U-shape. The handle pipe 32 extends from the frame pipe 16 toward the left side, then toward the rear upper side, then toward the rear side, and also extends from the frame pipe 16 toward the right side, then toward the rear upper side, and then toward the rear side. The reinforcing pipe 34 is made of a metal material. The reinforcing pipe 34 is connected to a left portion of the handle pipe 32 located on the left side of the frame pipe 16, and a right portion of the handle pipe 32 located on the right side of the frame pipe 16. The left grip 36 and the right grip 38 are made of a resin material. The left grip 36 is attached to the left rear end of the handle pipe 32. The right grip 38 is attached to the right rear end of the handle pipe 32. A user can move the work machine 2 by standing behind the work machine 2, holding the left grip 36 and the right grip 38, and pushing the handle unit 6 forward.

[0033] The switch box unit 40 includes a switch box 44, a main power switch 46, a switch lever 48, and a lock-off button 50. The switch box 44 is attached to the handle pipe 32 at a position in front of the right grip 38. The switch box 44 is made of a resin material. The main power switch 46 is disposed on the upper surface of the switch box 44. The main power switch 46 can be switched between an ON state in which the working unit 10 is operable and an OFF state in which the working unit 10 is inoperable. The switch lever 48 and the lock-off button 50 are made of a resin material. The switch lever 48 is rotatably attached to the rear end of the switch box 44. The lock-off button 50 is attached to the left wall of the switch box 44 so as to be able to be pressed in. When the lock-off button 50 is pressed in and the switch lever 48 is pushed up, the working unit 10 is driven.

[0034] The switch box guard 42 is made of a metal material. The switch box guard 42 includes an attachment portion 52 and a protruding portion 54. The attachment portion 52 is fixed to the handle pipe 32 at a position in front of the switch box unit 40. As shown in FIG. 4, the protruding portion 54 protrudes to the right from the attachment portion 52. The protruding portion 54 protrudes to the right beyond the right end of the switch box unit 40. Therefore, when the work machine 2 is tilted to the right, the protruding portion 54 abuts against the ground P before the switch box unit 40 does, and absorbs the impact from the ground P. This makes it possible to prevent the switch box unit 40 from being damaged.

[0035] As shown in Fig. 2, the main body unit 8 is attached to the frame unit 4. The main body unit 8 includes a transmission case unit 58, a housing unit 60, and a battery mounting unit 62 (see Fig. 8). The transmission case unit 58 is made of a metal material. The transmission case unit 58 is fixed to the front ends of the pair of base plates 14 by bolts 74.

[0036] As shown in Fig. 5, the transmission case unit 58 includes a first transmission case 76, a second transmission case 78, and a front handle 80. The first transmission case 76 extends in the vertical direction. The working unit 10 (see Fig. 1) is disposed at the lower end of the first transmission case 76. The first transmission case 76 has bolt holes 82 into which the bolts 74 are inserted, and a gear accommodating groove 84 recessed downward from the upper surface of the first transmission case 76.

[0037] The second transmission case 78 includes a plate portion 86 and a cylindrical portion 88. The plate portion 86 is fixed to the upper surface of the first transmission case 76 with bolts 90. The cylindrical portion 88 protrudes upward from the plate portion 86. The cylindrical portion 88 has a cylindrical shape. The cylindrical portion 88 has a coupling accommodating space 92 defined by its inner circumferential surface.

[0038] The front handle 80 is fixed near the front end of the first transmission case 76. The front handle 80 protrudes forward from the first transmission case 76. As shown in FIG. 2, the front handle 80 protrudes forward beyond the housing unit 60.

[0039] The housing unit 60 is attached to an upper portion of the transmission case unit 58. The housing unit 60 is made of a resin material. As shown in Fig. 6, the housing unit 60 includes a main housing 94, a cover 96, and a fender 98. The main housing 94 is a separate body from each of the cover 96 and the fender 98.

[0040] The main body housing 94 includes an upper main body housing 100 and a lower main body housing 102. The upper main body housing 100 is separate from the lower main body housing 102. As shown in Figs. 6 and 7, the upper main body housing 100 includes a first neck portion 104, a head portion 106, and a rear connecting portion 108. The head portion 106 is disposed above the first neck portion 104. The rear connecting portion 108 is connected to both the rear upper portion of the first neck portion 104 and the rear lower portion of the head portion 106. The rear connecting portion 108 has a substantially rectangular shape.

[0041] The upper main body housing 100 has an intake port 110 that penetrates the bottom wall 108a of the rear connecting portion 108 in the up-down direction. The intake port 110 communicates the inside and outside of the upper main body housing 100. The intake port 110 has a plurality of intake openings 112. A cross section of each of the plurality of intake openings 112 has a substantially rectangular shape extending in the front-rear direction. The plurality of intake openings 112 open downward toward the ground P (see FIG. 2). The plurality of intake openings 112 are lined up in the left-right direction.

[0042] As shown in FIG. 8, a cover 96 is rotatably attached to the upper end of the upper main body housing 100. A rotation axis RX of the cover 96 is located at the front end of the upper main body housing 100. The cover 96 rotates between a closed position and an open position. As shown in FIG. 9, when the cover 96 is located at the closed position, a battery storage space 114 is defined between the cover 96 and the upper surface of the head 106. As shown in FIG. 8, when a user stands behind the working machine 2 and rotates the cover 96 from the closed position (see FIG. 9) to the open position, the cover 96 opens from the rear side to the front side. When the working machine 2 is placed on the ground P in a working posture and the cover 96 is in the open position, and the user releases the cover 96, the cover 96 rotates from the open position to the closed position due to the weight of the cover 96.

[0043] As shown in Fig. 9, a battery mounting unit 62 is attached to the top surface of the head 106. An upper surface 62a of the battery mounting unit 62 is inclined with respect to a plane along the left-right and front-rear directions (i.e., the imaginary ground P). The upper surface 62a extends from the upper rear side to the lower front side. The vertical position of the upper surface 62a decreases from the rear end to the front end.

[0044] As shown in FIG. 8, two battery packs BP are detachably attached to the battery mounting unit 62. In FIG. 8, one battery pack BP is omitted from the illustration in order to make it easier to understand the position of the battery mounting unit 62. The battery pack BP is attached to the battery mounting unit 62 when it is slid on the upper surface 62a of the battery mounting unit 62 in an attachment direction D1 toward the lower front side with the cover 96 in the open position, and is detached from the battery mounting unit 62 when it is slid on the upper surface 62a in a removal direction D2 toward the upper rear side. The upper surface 62a of the battery mounting unit 62 corresponds to the slide surface on which the battery pack BP slides. The attachment direction D1 faces the ground P, and the removal direction D2 does not face the ground P. The two battery packs BP are aligned in the left-right direction when attached to the battery mounting unit 62.

[0045] The battery pack BP is equipped with a remaining power display unit 115. The remaining power display unit 115 displays the remaining power of the battery pack BP. When the battery pack BP is attached to the battery mounting unit 62, the remaining power display unit 115 faces rearward and upward. Therefore, when the battery pack BP is attached to the battery mounting unit 62 and the cover 96 is in the open position, the user can easily view the remaining power display unit 115.

[0046] In this embodiment, when two battery packs BP are attached to the battery mounting unit 62, the power of one battery pack BP (for example, the left battery pack BP) is used first. When the remaining power of one battery pack BP becomes zero, the power of the other battery pack BP (for example, the right battery pack BP) is used next. Therefore, even when the power of the other battery pack BP is being used, the one battery pack BP whose remaining power has become zero can be removed from the battery mounting unit 62 and a new battery pack BP can be attached to the battery mounting unit 62. In addition, two indicator lamps 116 are disposed near the rear end of the upper surface of the head 106. The left indicator lamp 116 lights up or flashes when the remaining power of the left battery pack BP becomes equal to or less than a predetermined value, and the right indicator lamp 116 lights up or flashes when the remaining power of the right battery pack BP becomes equal to or less than a predetermined value.

[0047] As shown in Fig. 6, the lower main body housing 102 is disposed below the upper main body housing 100. As shown in Fig. 10, the lower main body housing 102 defines an accommodation space 120 between itself and the upper main body housing 100. The main body unit 8 further includes a partition member 122, which divides the accommodation space 120 into an upper accommodation space 124 and a lower accommodation space 126. The upper accommodation space 124 is defined by the upper main body housing 100 and the partition member 122. The lower accommodation space 126 is defined by the lower main body housing 102 and the partition member 122.

[0048] The partition member 122 is made of a metal material. The partition member 122 includes an upper partition member 128 and a lower partition member 129. The upper partition member 128 includes a flange portion 130, a cylindrical portion 132, and a bottom wall portion 134. The flange portion 130 is fixed to the upper main body housing 100. The cylindrical portion 132 is disposed below the flange portion 130. The cylindrical portion 132 has a cylindrical shape. The bottom wall portion 134 is disposed at the lower end of the cylindrical portion 132. The bottom wall portion 134 has a plate shape. The bottom wall portion 134 has a through hole 136 that penetrates the bottom wall portion 134 in the thickness direction (vertical direction).

[0049] The lower partition member 129 is disposed below the upper partition member 128. The lower partition member 129 is fixed to the upper partition member 128. The lower partition member 129 has a generally plate shape. The lower partition member 129 has a through hole 138 that passes through the lower partition member 129 in the thickness direction (vertical direction). The through hole 138 overlaps with the through hole 136 of the bottom wall portion 134 in the vertical direction.

[0050] As shown in Figures 6 and 7, the lower main body housing 102 includes a second neck portion 140, a cylindrical portion 142, and a bottom wall portion 144. The second neck portion 140 is attached to the lower end of the first neck portion 104. The cylindrical portion 142 is disposed below the second neck portion 140. The cylindrical portion 142 has a substantially cylindrical shape. The bottom wall portion 144 is disposed at the lower end of the cylindrical portion 142. The bottom wall portion 144 has a plate shape. The bottom wall portion 144 has a through hole 145 that penetrates the bottom wall portion 144 in the thickness direction (vertical direction).

[0051] The cylindrical portion 142 has a front communication port 146 and a rear communication port 147 penetrating the cylindrical portion 142 in the thickness direction. The vertical position of the front communication port 146 is substantially the same as the vertical position of the rear communication port 147. The front communication port 146 and the rear communication port 147 each communicate between the lower accommodation space 126 (see FIG. 10) and the outside of the lower main body housing 102. The front communication port 146 and the rear communication port 147 are spaced apart from each other in the circumferential direction of the outer circumferential surface of the cylindrical portion 142. The front communication port 146 is located in the front part of the cylindrical portion 142, and the rear communication port 147 is located in the rear part of the cylindrical portion 142. The front communication port 146 and the rear communication port 147 each have a plurality of communication openings 148. The cross section of each of the plurality of communication openings 148 has a substantially rectangular shape extending in the vertical direction. The multiple communication ports 148 open in a direction perpendicular to the up-down direction toward the radially outer side of the cylindrical portion 142. In each of the front communication port 146 and the rear communication port 147, the multiple communication ports 148 are lined up in the circumferential direction on the outer circumferential surface of the cylindrical portion 142. In addition, the total opening area of ​​the multiple communication ports 148 of the front communication port 146 and the total opening area of ​​the multiple communication ports 148 of the rear communication port 147 are each larger than the total opening area of ​​the multiple intake ports 112.

[0052] As shown in Fig. 11, the lower main body housing 102 further includes a peripheral rib 150, an annular rib 152, and a plurality of (16 in this embodiment) radial ribs 154. The peripheral rib 150, the annular rib 152, and the plurality of radial ribs 154 are connected to an upper surface 144a of the bottom wall portion 144. As shown in Fig. 12, the plurality of radial ribs 154 are also connected to an inner circumferential surface 142a of the cylindrical portion 142, the peripheral rib 150, and the annular rib 152. The peripheral rib 150, the annular rib 152, and the plurality of radial ribs 154 protrude upward from the upper surface 144a of the bottom wall portion 144. The upper ends of the peripheral rib 150, the upper end of the annular rib 152, and the upper ends of the multiple radial ribs 154 are positioned lower (toward the bottom wall portion 144) than the lower end of the rear communication port 147 and the lower end of the front communication port 146 (see Figure 6).

[0053] 11, the peripheral rib 150 goes around the periphery of the through-hole 145. The peripheral rib 150 is spaced apart from the inner circumferential surface 142a of the cylindrical portion 142.

[0054] The annular rib 152 has an annular shape. The annular rib 152 is disposed between the inner circumferential surface 142a of the cylindrical portion 142 and the peripheral rib 150. The annular rib 152 is spaced apart from the inner circumferential surface 142a of the cylindrical portion 142 and the peripheral rib 150.

[0055] The multiple radial ribs 154 extend from the inner peripheral surface 142a of the cylindrical portion 142 to the peripheral rib 150. The multiple radial ribs 154 extend from the inner peripheral surface 142a of the cylindrical portion 142 toward the radially inward direction of the cylindrical portion 142. The multiple radial ribs 154 are arranged at equal intervals in the circumferential direction of the inner peripheral surface 142a of the cylindrical portion 142. The multiple radial ribs 154 divide the space between the inner peripheral surface 142a of the cylindrical portion 142 and the annular rib 152 into multiple first spaces 156. In addition, the multiple radial ribs 154 divide the space between the annular rib 152 and the peripheral rib 150 into multiple second spaces 158.

[0056] As shown in FIG. 12, each of the eight radial ribs 154 has a first space communication hole 160 and a second space communication hole 162. In this embodiment, the radial ribs 154 having the first space communication hole 160 and the second space communication hole 162 and the radial ribs 154 not having the first space communication hole 160 and the second space communication hole 162 are arranged alternately in the circumferential direction of the inner peripheral surface 142a of the cylindrical portion 142. The first space communication hole 160 and the second space communication hole 162 penetrate the radial rib 154 in the thickness direction. The first space communication hole 160 and the second space communication hole 162 are arranged at the lower end of the radial rib 154. The first space communication hole 160 is arranged between the inner peripheral surface 142a of the cylindrical portion 142 and the annular rib 152. The first space communication hole 160 communicates with the first spaces 156 adjacent to each other. The second space communication hole 162 is disposed between the annular rib 152 and the peripheral edge rib 150. The second space communication hole 162 communicates the adjacent second spaces 158 with each other.

[0057] As shown in Fig. 11, the bottom wall portion 144 further has a plurality of (eight in this embodiment) first drainage holes 164 and a plurality of (eight in this embodiment) second drainage holes 166. The first drainage holes 164 and the second drainage holes 166 penetrate the bottom wall portion 144 in the thickness direction (vertical direction). As shown in Fig. 12, the first drainage hole 164 is connected to the lower end of the first space communication hole 160. The first drainage hole 164 communicates the first space 156 with the outside of the lower main body housing 102 via the first space communication hole 160. Therefore, even if liquid flows into the first space 156 through, for example, a small gap at the connection between the upper main body housing 100 (see FIG. 7) and the lower main body housing 102, or through the front communication port 146 or the rear communication port 147, the liquid is discharged to the outside of the lower main body housing 102 through the first space communication hole 160 and the first water drain hole 164. The second water drain hole 166 is connected to the lower end of the second space communication hole 162. The second water drain hole 166 communicates between the second space 158 and the outside of the lower main body housing 102 via the second space communication hole 162. Therefore, even if liquid flows into the second space 158, for example, through a small gap at the connection point between the upper main body housing 100 and the lower main body housing 102, or through the front communication port 146 or the rear communication port 147, the liquid will be discharged to the outside of the lower main body housing 102 through the second space communication hole 162 and the second drainage hole 166.

[0058] As shown in Fig. 6, the fender 98 is disposed below the lower main body housing 102. The fender 98 is fixed to the transmission case unit 58 (see Fig. 5) and the lower main body housing 102 by bolts 90 (see Fig. 5). The fender 98 includes an surrounding wall portion 170, a bottom wall portion 172, and a partition portion 174.

[0059] The surrounding wall portion 170 has a generally rectangular cylindrical shape. As shown in Fig. 10, the surrounding wall portion 170 surrounds the lower end of the second neck portion 140 with a small gap between the surrounding wall portion 170 and the lower end of the second neck portion 140. The surrounding wall portion 170 also surrounds the cylindrical portion 142. The surrounding wall portion 170 is separated from the cylindrical portion 142.

[0060] The bottom wall portion 172 is disposed at the lower end of the surrounding wall portion 170. The bottom wall portion 172 is disposed below the lower main body housing 102. The bottom wall portion 172 has a plate shape. The bottom wall portion 172 faces the bottom wall portion 144 of the lower main body housing 102. The bottom wall portion 172 is separated from the bottom wall portion 144 in the up-down direction. As a result, an exhaust space 176 is defined between the surrounding wall portion 170 and the bottom wall portion 172 of the fender 98 and between the cylindrical portion 142 and the bottom wall portion 144 of the lower main body housing 102. The exhaust space 176 is in communication with the lower accommodation space 126 via the front communication port 146 and the rear communication port 147.

[0061] The lower main body housing 102 has a positioning protrusion 178 protruding downward from the bottom wall portion 144, and the bottom wall portion 172 has a positioning hole 180 that receives the positioning protrusion 178. The position of the fender 98 relative to the lower main body housing 102 is determined by the positioning hole 180 receiving the positioning protrusion 178. The bottom wall portion 172 further has two third drainage holes 182 that penetrate the bottom wall portion 172 in the thickness direction (up and down direction). The third drainage holes 182 communicate between the internal space (exhaust space 176) of the surrounding wall portion 170 and the external space. Therefore, even if liquid flows into the exhaust space 176 through a small gap between the surrounding wall portion 170 and the lower end of the second neck portion 140, or through the first drain hole 164 (see Figure 12) or the second drain hole 166 (see Figure 12), the liquid is discharged into the space outside the surrounding wall portion 170 through the third drain hole 182.

[0062] The bottom wall portion 172 has an exhaust port 184 penetrating the bottom wall portion 172 in the thickness direction (vertical direction). The exhaust port 184 opens downward toward the ground P (see FIG. 2). The exhaust port 184 overlaps with the through hole 145 of the lower main body housing 102 in the vertical direction. As shown in FIG. 13, the cylindrical portion 88 of the second transmission case 78 is inserted into the exhaust port 184. In the exhaust port 184, the bottom wall portion 172 is separated from the outer circumferential surface of the cylindrical portion 88. The opening area between the bottom wall portion 172 and the cylindrical portion 88 is larger than the total value of the total opening area of ​​the plurality of communication ports 148 (see FIG. 6) of the front communication port 146 and the total opening area of ​​the plurality of communication ports 148 (see FIG. 7) of the rear communication port 147. The opening area between the bottom wall portion 172 and the cylindrical portion 88 is larger than the opening area of ​​the third drainage hole 182.

[0063] As shown in FIG. 10, the partition wall 174 is connected to the upper end of the surrounding wall 170. The partition wall 174 surrounds the outer peripheral surface of the surrounding wall 170. The partition wall 174 extends from the surrounding wall 170 in a direction away from the surrounding wall 170. As shown in FIG. 2 and FIG. 14, the partition wall 174 has a shape in which the rear part of the partition wall 174 is longer than the front part of the partition wall 174. The partition wall 174 extends from the surrounding wall 170 so as to approach the ground P. The partition wall 174 is arranged so as to block the gap between the working unit 10 and a user (e.g., the upper body of the user) standing on the rear side of the working machine 2. This makes it possible to prevent soil or stones from hitting the user even if they are blown toward the user by the operation of the working unit 10. In addition, the partition wall 174 is arranged so as to partially cover the working unit 10. The partition portion 174 is disposed between the working unit 10 and the upper main body housing 100. The partition portion 174 separates a lower space 188 on the working unit 10 side from an upper space 190 on the upper main body housing 100 side.

[0064] 10, the intake port 110 is disposed closer to the upper main body housing 100 than the partition wall 174. Therefore, the intake port 110 is in communication with the upper space 190. Moreover, the exhaust port 184 is disposed closer to the working unit 10 than the partition wall 174. Therefore, the exhaust port 184 is in communication with the lower space 188.

[0065] 9, 10 and 14, the main unit 8 further includes a sponge member 194, a control unit 196, an upper motor case 198, an electric motor 200, a transmission unit 202, and a fan 204. The sponge member 194, the control unit 196, the upper motor case 198, and the electric motor 200 are disposed in the upper accommodation space 124.

[0066] 9, the sponge member 194 is disposed inside the rear connecting portion 108. The sponge member 194 is disposed directly above the intake port 110. The sponge member 194 is a foam having a plurality of minute holes.

[0067] The control unit 196 is disposed straddling the interior of the rear coupling part 108 and the interior of the head part 106. The control unit 196 is disposed approximately parallel in the up-down and left-right directions. The control unit 196 is separated from the rear inner surface of the rear coupling part 108 and the upper inner surface of the head part 106. The control unit 196 includes an inverter circuit having a plurality of switching elements, and a control circuit that controls the operation of each of the switching elements. The control unit 196 controls the electric motor 200.

[0068] The upper motor case 198 is made of a metal material. As shown in Figs. 9 and 10, the upper motor case 198 is disposed inside the first neck portion 104. The upper motor case 198 is disposed above the upper partition member 128. The upper motor case 198 is fixed to the upper partition member 128 by bolts (not shown). The upper motor case 198 defines a motor accommodating space 206 between itself and the upper partition member 128. An electric motor 200 is disposed in the motor accommodating space 206. The upper motor case 198 and the upper partition member 128 constitute the motor case 208, and the upper partition member 128 corresponds to the lower motor case.

[0069] The upper motor case 198 has a motor intake port 210 that communicates between the motor accommodating space 206 and the outside of the motor case 208. In addition, as shown in Fig. 15, the upper partition member 128 has a motor exhaust port 212 that penetrates the bottom wall portion 134. The motor exhaust port 212 is disposed near the cylindrical portion 132.

[0070] As shown in Figs. 9 and 10, the electric motor 200 is an outer rotor type brushless motor. The electric motor 200 is disposed in the upper space 190. The electric motor 200 is driven by power supplied from a battery pack BP (see Fig. 8). The electric motor 200 includes a stator 214 and a rotor 216. The stator 214 includes a stator core 218 and a plurality of coils 220 wound around the stator core 218. The rotor 216 includes a cylindrical rotor body 224 having a bottom wall 222 at its lower end, and a plurality of permanent magnets 226 fixed to the rotor body 224. The rotor 216 rotates about a rotation axis AX1 as a result of power from the battery pack BP (see Fig. 8) being supplied to the plurality of coils 220. The rotation axis AX1 extends in the vertical direction and is substantially perpendicular to the virtual ground P (see Fig. 14).

[0071] As shown in Figures 10 and 14, the transmission unit 202 includes a first transmission shaft 230, a jaw coupling 232, a first helical gear 236, a second helical gear 238, a second transmission shaft 240, a worm gear 242, a worm wheel 244, and output shafts 246, 248.

[0072] The first transmission shaft 230 is made of a metal material. As shown in Fig. 10, the first transmission shaft 230 is inserted into and fitted into the bottom wall 222 of the rotor body 224. The first transmission shaft 230 is rotatably supported by the motor case 208 via a bearing 249 and a bearing 250. The first transmission shaft 230 rotates together with the rotor 216 about the rotation axis AX1. The first transmission shaft 230 is inserted into the through hole 136 of the upper partition member 128 and the through hole 138 of the lower partition member 129.

[0073] The jaw coupling 232 is disposed across the gear accommodating groove 84, the coupling accommodating space 92, and the lower accommodating space 126. The jaw coupling 232 is inserted into the through hole 145 of the lower main body housing 102 and the exhaust port 184 of the fender 98. The jaw coupling 232 includes a first member 252, a connecting member 254, and a second member 256. The first member 252 is made of a metal material. The first member 252 is fitted to the lower end of the first transmission shaft 230. The lower end of the first transmission shaft 230 is inserted into the first member 252. Therefore, the jaw coupling 232 rotates together with the first transmission shaft 230 about the rotation axis AX1.

[0074] The first member 252 is inserted into the fan 204. The fan 204 is made of a resin material. The fan 204 is fitted into the first member 252. The fan 204 is, for example, a centrifugal fan. The vertical position of the fan 204 is substantially the same as the vertical position of the front communication port 146 and the vertical position of the rear communication port 147. In the radial direction of the fan 204, the fan 204 faces each of the front communication port 146 and the rear communication port 147. The fan 204 rotates around the rotation axis AX1 together with the jaw coupling 232. The fan 204 sends out air toward each of the front communication port 146 and the rear communication port 147.

[0075] 16, the first member 252 has three first claws 258 located at the lower end. The three first claws 258 are disposed at equal intervals around the rotation axis AX1. The interval between adjacent first claws 258 in the circumferential direction of the rotation axis AX1 is 120 degrees.

[0076] The connecting member 254 connects the first member 252 and the second member 256. The connecting member 254 is made of a resin material. The connecting member 254 has a disk shape. The connecting member 254 has six claw receiving holes 260 penetrating the connecting member 254 in the thickness direction (up and down direction). The six claw receiving holes 260 are arranged at equal intervals around the rotation axis AX1. The interval between adjacent claw receiving holes 260 in the circumferential direction of the rotation axis AX1 is 60 degrees. When the connecting member 254 is connected to the first member 252, the three claw receiving holes 260 receive the three first claws 258.

[0077] The second member 256 is made of a metal material. The second member 256 has three second claws 262 located at the upper end. The three second claws 262 are arranged at equal intervals around the rotation axis AX1. The interval between adjacent second claws 262 in the circumferential direction of the rotation axis AX1 is 120 degrees. When the connecting member 254 is connected to the second member 256, the three second claws 262 are received in the remaining three claw receiving holes 260 that do not receive the first claws 258.

[0078] 14, the second member 256 is rotatably supported on the second transmission case 78 via a bearing 264. The vicinity of the upper end of the second member 256 and the connecting member 254 are disposed across the gear accommodating groove 84 and the coupling accommodating space 92.

[0079] The first helical gear 236 and the second helical gear 238 are made of a metallic material. The first helical gear 236 and the second helical gear 238 are disposed in the gear accommodating groove 84. The first helical gear 236 is fitted into the second member 256. The second helical gear 238 is disposed forward of the first helical gear 236. The second helical gear 238 meshes with the first helical gear 236.

[0080] The first transmission case 76 has a shaft hole 266 extending in the vertical direction, and the second transmission shaft 240 is inserted into the shaft hole 266. The second transmission shaft 240 is made of a metal material. The second transmission shaft 240 extends in the vertical direction. The upper end of the second transmission shaft 240 is fitted into the second helical gear 238. The second transmission shaft 240 is rotatably supported by the first transmission case 76 via bearings 268, 270, and 272. The second transmission shaft 240 rotates together with the jaw coupling 232 because the first helical gear 236 and the second helical gear 238 are engaged with each other. The rotation axis AX2 of the second transmission shaft 240 is offset forward with respect to the rotation axis AX1 of the jaw coupling 232. The rotation axis AX2 extends in the vertical direction and is substantially perpendicular to the virtual ground P.

[0081] The worm gear 242 and the worm wheel 244 are made of a metal material. The worm gear 242 is fitted in the vicinity of the lower end of the second transmission shaft 240. The first transmission case 76 has a wheel accommodating space 276 having a substantially circular plate shape, and the worm wheel 244 is disposed in the wheel accommodating space 276. The worm wheel 244 has a substantially circular plate shape. The worm wheel 244 meshes with the worm gear 242. When the worm gear 242 rotates about the rotation axis AX2, the worm wheel 244 rotates about the rotation axis AX3. The rotation axis AX3 is substantially parallel to the virtual ground P and extends in the left-right direction along the virtual ground P. The direction in which the rotation axis AX3 extends is different from the directions in which the rotation axes AX1 and AX2 extend.

[0082] As shown in FIG. 17, the output shafts 246, 248 are fitted to the worm wheel 244. The output shafts 246, 248 are made of a metal material. The output shaft 246 extends leftward from the worm wheel 244, and the output shaft 248 extends rightward from the worm wheel 244. The output shafts 246, 248 are rotatably supported by the first transmission case 76 (see FIG. 14) via bearings (not shown). The output shafts 246, 248 rotate together with the worm wheel 244 about the rotation axis AX3. The output shafts 246, 248 rotate the working unit 10.

[0083] As shown in FIG. 18, the working unit 10 includes a left working unit 280 and a right working unit 282. The left working unit 280 and the right working unit 282 are made of a metal material. The left working unit 280 includes a left claw mounting box 284, a plurality of left working claws 286, and a left plate 288. The left claw mounting box 284 is fixed to the output shaft 246. Therefore, the left working unit 280 rotates around the rotation axis AX3 together with the output shaft 246. The left claw mounting box 284 extends leftward from the output shaft 246. The left claw mounting box 284 extends leftward beyond the left end of the fender 98. In FIG. 18, the outer shape of the fender 98 is shown by a dashed line. The plurality of left working claws 286 are fixed to the left claw mounting box 284. The left working claw 286 is, for example, a tilling claw. The multiple left work claws 286 rotate to till the soil of the ground P. The left plate 288 is attached to the left end of the left claw attachment box 284.

[0084] The right working unit 282 includes a right claw mounting box 292, a plurality of right work claws 294, and a right plate 296. The right claw mounting box 292 is fixed to the output shaft 248. Therefore, the right working unit 282 rotates around the rotation axis AX3 together with the output shaft 248. The right claw mounting box 292 extends rightward from the output shaft 248. The right claw mounting box 292 extends rightward beyond the right end of the fender 98. The plurality of right work claws 294 are fixed to the right claw mounting box 292. The right work claw 294 is, for example, a tilling claw. The plurality of right work claws 294 till the soil of the ground P by rotating. The right plate 296 is attached to the right end of the right claw mounting box 292.

[0085] With reference to Figs. 18 to 20, the positional relationship between the battery pack BP, the working unit 10, the battery mounting unit 62, the control unit 196, the motor case 208 (electric motor 200), and the fan 204 will be described. As shown in Fig. 18, when the working machine 2 is placed in the working posture on the ground P and viewed from the front, the battery pack BP, the motor case 208 (electric motor 200), the fan 204, and the working unit 10 are spaced apart from one another in the vertical direction. When the working machine 2 is placed in the working posture on the ground P, the rotation axes AX1 and AX2 are approximately perpendicular to the virtual ground P. The working unit 10, the fan 204, the motor case 208 (electric motor 200), the battery mounting unit 62, and the battery pack BP are lined up in this order toward the top. The left battery pack BP, the battery mounting unit 62, the motor case 208 (electric motor 200), the fan 204, and the left working unit 280 are lined up in a vertical line. In addition, the right-side battery pack BP, the battery mounting unit 62, the motor case 208 (electric motor 200), the fan 204, and the right-side working unit 282 are aligned in a vertical line. The force due to the weight of the battery pack BP and the force due to the weight of the electric motor 200 act on the working unit 10, so that the working unit 10 is prevented from lifting off the ground P during work. The battery pack BP and the motor case 208 (electric motor 200) do not overlap in the front-rear direction or the left-right direction. The battery mounting unit 62 and the motor case 208 (electric motor 200) do not overlap in the front-rear direction or the left-right direction. The motor case 208 (electric motor 200) and the fan 204 do not overlap in the front-rear direction or the left-right direction. The fan 204 and the working unit 10 do not overlap in the front-rear direction or the left-right direction.

[0086] 19, when the work machine 2 is viewed from above while placed in a working posture on the ground P, the battery pack BP, the motor case 208 (electric motor 200), and the working unit 10 overlap one another. Although not shown, the fan 204 also overlaps with the battery pack BP, the motor case 208 (electric motor 200), and the working unit 10.

[0087] As shown in FIG. 20, when the work machine 2 is placed in the working posture on the ground P and viewed from the left side, the control unit 196 is disposed rearward of the battery pack BP and the battery mounting unit 62. The control unit 196 overlaps with the battery pack BP and the battery mounting unit 62 in the front-rear direction. The control unit 196 does not overlap with the battery pack BP and the battery mounting unit 62 in the up-down direction. The control unit 196 overlaps with the working unit 10 in the up-down direction. The control unit 196 is disposed rearward of the rotation axis AX3 of the working unit 10. The rotation axis AX3 of the working unit 10 is disposed rearward of the rotation axis AX1 of the electric motor 200. The center of gravity G1 of the battery pack BP is disposed forward of the rotation axes AX1, AX2, and AX3.

[0088] Next, the operation of the work machine 2 will be described. As shown in Figs. 9, 10, and 14, when the working unit 10 is switched to the on state by operating the main power switch 46 (see Fig. 1), the lock-off button 50 (see Fig. 1) is pressed, and the switch lever 48 (see Fig. 1) is pushed upward, the control unit 196 supplies power from the battery pack BP to the multiple coils 220 of the electric motor 200. This causes the rotor 216 to rotate about the rotation axis AX1. Thereafter, the rotation of the rotor 216 is transmitted to the working unit 10 via the first transmission shaft 230, the jaw coupling 232, the first helical gear 236, the second helical gear 238, the second transmission shaft 240, the worm gear 242, the worm wheel 244, and the output shafts 246 and 248 in this order. This causes the working unit 10 to rotate about the rotation axis AX3. Furthermore, the direction in which the rotation shaft AX3 extends (left-right direction) is changed to a direction different from the direction in which the rotation shafts AX1 and AX2 extend (up-down direction) by the worm gear 242 and the worm wheel 244. As the work unit 10 rotates, the soil on the ground P is tilled by the left work claw 286 (see FIG. 17) and the right work claw 294.

[0089] When the rotor 216 rotates, the fan 204 also rotates. This generates an air flow in the housing unit 60. In Figs. 9, 10, 13, and 14, the air flow is illustrated by arrows. Specifically, as shown in Fig. 9, the air first flows from the space outside the main body housing 94 (the upper space 190) through the intake port 110 into the upper housing space 124. Next, the air flows upward between the control unit 196 and the rear connecting part 108 through the sponge member 194, and then bends and flows forward between the control unit 196 and the upper inner surface of the head 106. This cools the control unit 196. In addition, since the air passes through the sponge member 194, it is possible to prevent foreign matter such as dust from flowing into the upper housing space 124. Next, the air bends and flows downward toward the motor case 208. As shown in Fig. 10, the air then flows into the motor housing space 206 through the motor intake port 210. Next, the air passes through the electric motor 200, and then passes through the motor exhaust port 212 (see FIG. 15) and the through hole 138 of the lower partition member 129 in that order, before flowing into the lower accommodation space 126. This cools the electric motor 200.

[0090] Next, the air flows downward to the fan 204, and is then sent out by the fan 204 radially outward (in a direction perpendicular to the rotation axis AX1). As shown in FIG. 13, the air then flows into the exhaust space 176 through the front communication port 146 and the rear communication port 147 (see FIG. 6). Next, the air flows downward, and then bends and flows toward the rotation axis AX1 (see FIG. 10) to the exhaust port 184. Next, the air passes between the bottom wall portion 172 of the fender 98 and the second transmission case 78, and flows out of the exhaust port 184 into a space outside the main body housing 94 (lower space 188). As shown in FIG. 14, the air flows toward the working unit 10 (toward the ground P).

[0091] In this embodiment, the battery mounting unit 62, the cover 96, the upper main body housing 100, the sponge member 194, the control unit 196, the electric motor 200, the motor case 208, the lower partition member 129, and the first transmission shaft 230 are also used in a work machine 2 other than a tiller. Hereinafter, the above nine components are collectively referred to as a common unit 300. As shown in FIG. 21, the common unit 300 is used in, for example, a lawnmower 400. The common unit 300 is attached to a deck 402 of the lawnmower 400. The lawnmower 400 is a hand-pushed or self-propelled electric work machine. The cutting blade 404 of the lawnmower 400 is fitted to the first transmission shaft 230 (see FIG. 10) of the common unit 300. Therefore, the cutting blade 404 rotates around the rotation axis AX1. The cutting blade 404 can cut grass on the ground P (see FIG. 2) by rotating.

[0092] (effect) The working machine 2 of this embodiment performs work while moving on the ground surface P. The working machine 2 includes an electric motor 200, a fan 204 that rotates when driven by the electric motor 200, a housing unit 60 that houses the electric motor 200 and the fan 204, a work unit 10 that rotates about a rotation axis AX3 that is approximately parallel to a virtual ground surface P perpendicular to the up-down direction when driven by the electric motor 200 and performs work on the ground surface P, and a transmission unit 202 (an example of an axis changing unit) that transmits the rotation of the electric motor 200 to the work unit 10 and changes the direction of the rotation axis AX3 of the work unit 10 to a direction different from the direction of the rotation axis AX1 of the electric motor 200. The housing unit 60 has an intake port 112 through which air flows from the outside of the housing unit 60 to the inside by the rotation of the fan 204, and an exhaust port 184 through which the air sent out by the fan 204 flows from the inside of the housing unit 60 to the outside. The exhaust port 184 communicates with a lower space 188 (an example of a space) on the working unit 10 side.

[0093] According to the above configuration, the air flowing out from the exhaust port 184 flows toward the working unit 10 and hits the ground P. Therefore, it is possible to prevent the air flowing out from the exhaust port 184 from hitting the user.

[0094] The housing unit 60 also includes a partition portion 174 disposed between the electric motor 200 and the working unit 10 .

[0095] According to the above-mentioned configuration, the upper space 190 on the electric motor 200 side and the lower space 188 on the working unit 10 side can be separated by a simple configuration in which the partition wall 174 is provided.

[0096] Further, the exhaust port 184 is disposed on the working unit 10 side with respect to the partition wall portion 174 .

[0097] According to the above configuration, the partition 174 can prevent the air flowing out from the exhaust port 184 from flowing from the lower space 188 on the working unit 10 side to the upper space 190 on the electric motor 200 side. This can further prevent the air flowing out from the exhaust port 184 from hitting the user.

[0098] Moreover, the air intake 112 is disposed on the electric motor 200 side with respect to the partition wall 174 .

[0099] Sand and dust may be scattered on the ground P in the lower space 188 on the working unit 10 side. With the above-described configuration, it is possible to prevent the sand and dust from flowing into the housing unit 60 through the intake port 112.

[0100] The housing unit 60 also includes a main housing 94 that houses the electric motor 200 and the fan 204. The main housing 94 is a separate body from the partition wall portion 174.

[0101] According to the above configuration, the partition wall portion 174 can be easily replaced depending on the configuration of the working unit 10.

[0102] The main body housing 94 also includes an upper main body housing 100 (an example of a first main body housing) that houses the electric motor 200, and a lower main body housing 102 (an example of a second main body housing) that is separate from the upper main body housing 100 and houses the fan 204.

[0103] According to the above configuration, the combination of the electric motor 200 and the fan 204 can be easily changed.

[0104] Moreover, the air intake 112 opens downward.

[0105] According to the above configuration, it is possible to prevent liquid such as rainwater from flowing into the inside of the housing unit 60 through the intake port 112.

[0106] Furthermore, when the fan 204 rotates, air flows through the housing unit 60 from the air intake 112 to the air exhaust 184. The work machine 2 is disposed between the air intake 112 and the electric motor 200 in the air flow direction, and includes a control unit 196 that controls the electric motor 200.

[0107] According to the above configuration, the cooling performance of the control unit 196 can be improved.

[0108] Moreover, the fan 204 is a centrifugal fan.

[0109] According to the above configuration, the flow rate of air sent out from the fan 204 can be increased.

[0110] The working machine 2 further includes a handle unit 6 that is held by a user. The working machine 2 is a push-type working machine that is moved by the user pushing the handle unit 6 forward.

[0111] In a push-type working machine, a user stands behind the working machine 2 to operate the working machine 2. According to the above configuration, even when the user is standing behind the working machine 2, it is possible to prevent the air flowing out from the exhaust port 184 from hitting the user.

[0112] (Modification) In one embodiment, the working machine 2 may be a lawn care machine such as a scarifier or a snow removal machine. The working machine 2 may also be an electric brush that removes dirt by rotating brush bristles, or an electric sweeper that removes dirt or cuts grass by rotating a drum on which multiple rubber spatulas are formed.

[0113] The work machine 2 according to one embodiment may be provided with a built-in battery instead of the battery pack BP. In this case, the built-in battery is charged by being connected to an external power source via a connection cable. The built-in battery is accommodated in the housing unit 60.

[0114] The work machine 2 according to one embodiment may be equipped with a backpack battery instead of the battery pack BP. The backpack battery is detachable from a backboard worn on the user's back. The backpack battery is attached to the top surface of the upper main body housing 100.

[0115] The work machine 2 according to one embodiment does not necessarily have to be equipped with the pair of wheels 24 .

[0116] In the transmission unit 202 according to one embodiment, a screw groove may be formed near the lower end of the second member 256 of the jaw coupling 232, and a bevel gear may mesh with the screw groove. This changes the direction of the rotation axis from the direction of the rotation axis AX1 of the jaw coupling 232 (up-down direction) to the left-right direction. After that, the rotation of the bevel gear may be transmitted to the output shafts 246, 248 via a belt or a spur gear.

[0117] The main unit 8 according to one embodiment does not need to include the partition member 122. In this case, the storage space 120 is not divided into the upper storage space 124 and the lower storage space 126.

[0118] In the housing unit 60 according to one embodiment, the upper main body housing 100 and the lower main body housing 102 may be integrally formed. Also, the partition wall portion 174 of the fender 98 may be detachably attached to the lower main body housing 102. Also, the fender 98 does not have to include the surrounding wall portion 170 and the bottom wall portion 172.

[0119] In the housing unit 60 according to one embodiment, the lower main body housing 102 and the partition wall portion 174 of the fender 98 may be integrally formed.

[0120] In the housing unit 60 according to one embodiment, the lower main body housing 102, the surrounding wall portion 170 of the fender 98, and the bottom wall portion 172 may be integrally formed. In this case, the partition wall portion 174 of the fender 98 may be detachably attached to the lower main body housing 102.

[0121] In one embodiment of the lower body housing 102 , the through-holes 145 may function as exhaust ports through which air can flow to the outside of the housing unit 60 .

[0122] In one embodiment, the fan 204 may be an axial fan. [Explanation of symbols]

[0123] 2: Work equipment 6: Handle unit 8: Main unit 10: Unit of Work 60: Housing unit 62: Battery mounting unit 94: Main housing 96: Cover 98: Fender 100: Upper body housing 102: Lower body housing 110: Intake port 112: Air intake 114: Battery storage space 120: Containment space 122: Partition member 124: Upper storage space 126: Lower storage space 146: Communication port 148: Connecting port 174: Partition wall part 176: Exhaust space 184: Exhaust port 188:Lower space 190: Upper space 196: Control unit 200: Electric motor 202: Transmission unit 204: Fan 208: Motor case 214: Stator 216: Rotor 230: First transmission shaft 232: Jaw coupling 240: Second transmission shaft 252: First member 254: Connecting member 256: Second member 280: Left side working unit 282: Right side working unit 300: Common unit 400: Lawnmower AX1, AX2, AX3: Rotation axis BP: Battery pack D1: Installation direction D2:Removal direction G1: Center of gravity P: Ground, virtual ground

Claims

1. A work machine that works while moving on the ground, An electric motor; a fan that is rotated by being driven by the electric motor; a housing unit that houses the electric motor and the fan; a working unit that rotates about a rotation axis that is substantially parallel to a virtual ground plane perpendicular to the up-down direction by being driven by the electric motor, and performs work on the ground plane; an axis changing unit that transmits the rotation of the electric motor to the working unit and changes the direction of the rotation axis of the working unit to a direction different from the direction of the rotation axis of the electric motor, The housing unit comprises: an intake port through which air flows from the outside to the inside of the housing unit by rotation of the fan; an exhaust port through which the air blown out by the fan flows from the inside of the housing unit to the outside, The exhaust port is in communication with a space on the working unit side.

2. The work machine according to claim 1 , wherein the housing unit includes a partition wall portion disposed between the electric motor and the working unit.

3. The work machine according to claim 2 , wherein the exhaust port is disposed on the working unit side with respect to the partition wall.

4. The work machine according to claim 3 , wherein the air intake is disposed on the electric motor side with respect to the partition wall.

5. the housing unit includes a main body housing that houses the electric motor and the fan, The work machine according to claim 2 , wherein the main body housing is a separate body from the partition wall.

6. The main body housing includes: a first main body housing that accommodates the electric motor; The work machine according to claim 5 , further comprising: a second main body housing that is separate from the first main body housing and that houses the fan.

7. The work machine according to claim 1 , wherein the air intake port opens downward.

8. When the fan rotates, air flows through the housing unit from the intake port to the exhaust port, The work machine according to claim 1 , wherein the work machine is disposed between the air intake port and the electric motor in the air flow direction, and includes a control unit that controls the electric motor.

9. The work machine according to claim 1 , wherein the fan is a centrifugal fan.

10. The device further includes a handle unit to be held by a user, The work machine according to claim 1 , wherein the work machine is a push-type work machine that is moved by the user pushing the handle unit forward.

Images