electric work vehicle

Abstract

To provide an electric work vehicle which can perform, when attaching a motor to a support member, attachment operation smoothly, perform positioning of the motor, and avoid damage to a surface of the motor.SOLUTION: An electric work vehicle comprises: a harness which connects a front part of a motor 40 with an invertor; and a positioning mechanism 7 with a first guide part 71 arranged at one of the motor 40 and a support member 50 and a second guide part 72 arranged at the other of the motor 40 and the support member 50 in which the first guide part 71 and the second guide part 72 abut on each other so that a position of the motor 40 is decided relative to the support member 50 when viewed in a forward and backward direction. When the motor 40 is attached to the support member 50, the positioning mechanism 7 is constructed so that the first guide part 71 and the second guide part 72 can abut on each other while a projection 45 is positioned ahead of a support front face 51.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an electric work vehicle equipped with a battery and a motor. [Background technology]

[0002] An example of an electric work vehicle like the one described above is already known, for example, from Patent Document 1. The motor in this electric work vehicle (referred to as a "tractor" in Patent Document 1) is driven by power supplied from a battery (referred to as a "driving battery" in Patent Document 1).

[0003] This electric work vehicle is equipped with an inverter that converts DC power from the battery into AC power and supplies it to the motor.

[0004] This motor is supported by a front support frame and a support member (referred to as a "rear support frame" in Patent Document 1). More specifically, the front support frame supports the front of the motor from below. The support member is in contact with the rear end of the motor and supports the rear of the motor.

[0005] The output shaft of the motor passes through the support member and extends rearward. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-953 Summary of the Invention [Problem to be solved by the invention]

[0007] It is possible to configure the electric work vehicle described in Patent Document 1 without a front support frame. In this case, the motor would be supported in a cantilevered manner on the support member. In such a configuration, if a recess that recesses rearward is formed on the front surface of the support member and a protrusion that fits into the recess is formed on the rear end of the motor, when the motor is attached to the support member, the engagement of the recess and the protrusion allows the motor to be positioned relative to the support member in the front-to-rear direction.

[0008] However, in a configuration having such a recess and protrusion, if the support member is made of a material with a relatively high hardness (e.g., iron), when the recess and protrusion are fitted together, it is possible that the protrusion will come into contact with the recess or its surroundings, causing scratches on the surface of the protrusion.

[0009] Furthermore, when a harness is provided to connect the motor and inverter in the electric work vehicle described in Patent Document 1, it is conceivable that the connection of the harness on the motor or the harness itself may interfere with the installation of the motor to the support member, making it difficult to install the motor to the support member smoothly.

[0010] The object of the present invention is to provide an electric work vehicle that allows smooth installation of a motor on a support member, allows the motor to be positioned, and makes it easy to avoid scratches on the surface of the motor. [Means for solving the problem]

[0011] The present invention is characterized in that it comprises: a battery; a motor supported by a support member and driven by power supplied from the battery; an inverter that converts DC power from the battery into AC power and supplies the AC power to the motor; and a harness that connects a front portion of the motor and the inverter, wherein power is supplied from the inverter to the motor via the harness, the motor is supported by the support member with an output shaft of the motor extending rearward through the support member, and a front support surface, which is the front surface of the support member, is formed with a recess that recesses rearward, and the motor has a contact surface that contacts the front support surface and a protruding portion that protrudes rearward beyond the contact surface and fits into the recess. the protruding portion is made of a first material, the support member is made of a second material having a higher hardness than the first material, and the motor has a first guide portion provided on one of the motor and the support member, and a second guide portion provided on the other of the motor and the support member, and is provided with a positioning mechanism that positions the motor with respect to the support member in a front-to-rear direction by the first guide portion and the second guide portion abutting against each other, and the positioning mechanism is configured so that when the motor is attached to the support member, the first guide portion and the second guide portion can abut against each other with the protruding portion positioned forward of the support front surface.

[0012] According to this configuration, when the motor is attached to the support member, the first guide portion and the second guide portion come into contact with each other before the protrusion fits into the recess. This allows the motor to be positioned. Furthermore, by moving the motor rearward while the first guide portion and the second guide portion remain in contact with each other, the protrusion can be fitted into the recess with the motor positioned relative to the support member in the front-to-rear direction. This makes it less likely that the surface of the protrusion will be scratched compared to when the protrusion is fitted into the recess with the motor not positioned relative to the support member in the front-to-rear direction (a state in which the motor can move freely relative to the support member in the front-to-rear direction).

[0013] Furthermore, with this configuration, the motor is attached to the support member from the front, and the harness connecting the motor and inverter is connected to the front of the motor, so the harness connection on the motor and the harness itself are less likely to interfere with the installation of the motor to the support member, compared to when the harness is connected to the rear of the motor.

[0014] In other words, with this configuration, when the motor is attached to the support member, the attachment work can be carried out smoothly, the motor can be positioned, and an electric work vehicle can be realized that makes it easy to avoid scratches on the surface of the motor.

[0015] Furthermore, in the present invention, it is preferable that the first guide portion is a pin extending in the front-to-rear direction, the second guide portion is a hole portion that fits into the pin, the positioning mechanism has a plurality of positioning portions, and each of the positioning portions includes one of the first guide portion and one of the second guide portion that correspond to each other.

[0016] This configuration allows for a relatively simple positioning mechanism that positions the motor relative to the support member in the front-to-rear direction. Furthermore, the engagement of multiple sets of pins and holes prevents the motor from rotating relative to the support member in the front-to-rear direction during installation. This makes it easier to install the motor relative to the support member than if the positioning mechanism had only one set of pins and holes.

[0017] Furthermore, in the present invention, it is preferable that the positioning mechanism has three or more positioning portions.

[0018] If the positioning mechanism has only two positioning parts, for example, one positioning part may be located to the left and one to the right of the axis of the output shaft of the motor. In this case, if the axis of the output shaft is located on a line connecting the two positioning parts when viewed from the front to back, and the distances from the axis of the output shaft to each positioning part are equal, it is conceivable that an operator attaching the motor to the support member may accidentally attach the motor upside down.

[0019] With this configuration, compared to when the positioning mechanism has only two positioning parts, the worker assembling the motor to the support member can easily accurately grasp the correspondence between the pins and the holes when looking at the arrangement of the pins and the holes, which makes it less likely that the worker will mistakenly attempt to install the motor upside down.

[0020] Furthermore, in the present invention, it is preferable that the positioning mechanism has three of the positioning portions, and that the three positioning portions are arranged so that, when viewed in the front-to-back direction, the triangle with each of the positions of the three positioning portions as vertices is not an equilateral triangle.

[0021] If the positioning mechanism has only three positioning parts, it is conceivable to arrange the positioning parts so that the triangle with the positions of the three positioning parts as vertices forms an equilateral triangle. In this configuration, if the distance from the axis of the output shaft to each positioning part is equal when viewed from the front to back, it is conceivable that an operator attaching the motor to the support member may attach the motor in an orientation that is rotated 120 degrees to the left or right from the correct orientation.

[0022] According to this configuration, the three positioning parts are arranged so that the triangle with the vertices at the positions of the three positioning parts is not an equilateral triangle. This makes it possible to fit all the pins into the holes only when the motor is in the correct orientation when viewed from the front to back. This prevents the worker installing the motor on the support member from installing it in an orientation that is rotated 120 degrees left or right from the correct orientation, as described above.

[0023] Furthermore, in the present invention, it is preferable that the plurality of positioning portions are arranged so as to be distributed above and below the axis of the output shaft.

[0024] When multiple positioning parts are concentrated above or below the axis of the output shaft, the weight of the motor and other factors can cause relatively large stresses to be applied to the pins when the pins are fitted into the corresponding holes. To prevent this stress from damaging the pins, the pins must be made of a relatively strong material, which can increase manufacturing costs.

[0025] With this configuration, the motor is less likely to apply a relatively large amount of stress to the pin compared to when multiple positioning parts are concentrated above or below the axis of the output shaft, which prevents damage to the pin and avoids an increase in manufacturing costs.

[0026] Furthermore, in the present invention, it is preferable that, of the plurality of positioning portions, the number of positioning portions arranged above the axis is greater than the number of positioning portions arranged below the axis.

[0027] When each pin is fitted into its corresponding hole, stress is applied to each pin from the motor due to factors such as the motor's weight. The total stress applied from the motor to each pin located above the axis of the positioning mechanism tends to be greater than the total stress applied from the motor to each pin located below the axis. Therefore, when the number of pins located above the axis is relatively small, relatively large stress tends to be applied to each pin located above the axis. Therefore, to prevent the pins from being damaged by this stress, it becomes necessary to form the pins from a relatively high-strength material. This tends to increase manufacturing costs.

[0028] According to this configuration, the number of pins arranged above the axis is relatively large, so that relatively large stress is not likely to be applied to each pin arranged above the axis, and therefore, it is possible to prevent the pins from being damaged and avoid an increase in manufacturing costs.

[0029] Furthermore, in the present invention, it is preferable that the pin is attached to a pin mounting surface which is one of the support front surface and the contact surface, and protrudes forward or rearward from the pin mounting surface, and that the length from the pin mounting surface to the protruding end of the pin is longer than the protruding length of the protruding portion.

[0030] This configuration makes it easy to reliably realize a configuration in which, when the motor is attached to the support member, the pin and the hole can abut against each other with the protrusion positioned forward of the support front surface. In other words, this configuration makes it easy to reliably realize an electric work vehicle in which the motor can be positioned when attached to the support member and scratches on the motor surface can be easily avoided.

[0031] Furthermore, in the present invention, it is preferable that a tapered portion is formed at the protruding end of the pin, and the length from the pin mounting surface to the base end of the tapered portion is longer than the protruding length of the protruding portion.

[0032] According to this configuration, the protruding end of the pin is formed with a tapered portion, so that when attaching the motor to the support member, the worker can easily insert the pin into the hole.

[0033] Furthermore, from the time when the tip of the tapered portion begins to enter the hole until the base end of the tapered portion enters the hole, the deeper the tapered portion enters the hole, the higher the positioning accuracy of the motor in the front-to-rear direction. With this configuration, the entire tapered portion from its tip to its base end can be inserted into the hole while the protrusion is positioned forward of the support front surface. This allows for accurate positioning when the motor is attached to the support member before the protrusion fits into the recess.

[0034] Furthermore, in the present invention, it is preferable that the pin is attached to the motor, and the hole is provided in the support member.

[0035] If a pin is attached to a support member and a hole is provided in the motor, when the pin and hole are fitted together, the pin may come into contact with the hole or its surrounding area, which may cause scratches around the hole in the motor.

[0036] According to this configuration, the pin is attached to the motor and the hole is provided in the support member, which prevents the motor from being damaged as described above.

[0037] Furthermore, in the present invention, it is preferable that the motor is fastened to the support member by a fastener, and that the positioning portion is located radially inward of the fastener in the radial direction of the output shaft.

[0038] When the positioning portion is located on the outer periphery of the fastener, the hole tends to be formed closer to the outer periphery of the motor or support member in the front-to-rear view. As a result, it is expected that the strength around the hole will be reduced. Therefore, measures such as reinforcing the area around the hole will be necessary. This tends to increase manufacturing costs.

[0039] According to this configuration, the hole is formed on the inner periphery side of the fastener. Therefore, it is easy to avoid the situation where the strength around the hole is reduced as described above. Therefore, it is less likely that measures such as reinforcing the area around the hole will be necessary. This makes it easy to avoid an increase in manufacturing costs.

[0040] Furthermore, in the present invention, it is preferable that the motor is supported in a cantilevered manner by the support member.

[0041] This configuration makes it easier to simplify the motor support structure compared to when the motor support structure is not cantilevered (for example, when it is double-supported), which makes it easier to suppress increases in manufacturing costs. [Brief explanation of the drawings]

[0042] [Figure 1] FIG. 2 is a left side view of the tractor. [Figure 2] FIG. 2 is a partially cutaway plan view showing the configuration of a motor and other components. [Figure 3] FIG. 2 is a front view showing the configuration of a support member and the like. [Figure 4] FIG. 4 is a cross-sectional view showing the configuration of a positioning portion and the like. [Figure 5] FIG. 2 is a partially cutaway left side view showing the configuration of the motor and other components. [Figure 6] FIG. 10 is a partially cutaway left side view showing the configuration of a motor and other components in another embodiment (10). DETAILED DESCRIPTION OF THE INVENTION

[0043] An embodiment of the present invention will be described with reference to the drawings. In the following description, unless otherwise specified, the direction of arrow F in the drawings will be referred to as "front," the direction of arrow B as "rear," the direction of arrow L as "left," and the direction of arrow R as "right." Furthermore, the direction of arrow U in the drawings will be referred to as "up," and the direction of arrow D as "down."

[0044] [Overall configuration of the tractor] The tractor 1 of this embodiment (corresponding to the "electric work vehicle" of the present invention) will be described below. As shown in Figure 1, the tractor 1 has left and right front wheels 10, left and right rear wheels 11, and a cover member 12.

[0045] The tractor 1 also includes a machine body frame 2 and a driving section 3. The machine body frame 2 is supported by left and right front wheels 10 and left and right rear wheels 11.

[0046] The cover member 12 is disposed at the front of the vehicle body, and the driving section 3 is provided behind the cover member 12. In other words, the cover member 12 is disposed in front of the driving section 3.

[0047] The driver's unit 3 has a protective frame 30, a driver's seat 31, and a steering wheel 32. An operator can sit in the driver's seat 31. This allows the operator to get into the driver's unit 3. The left and right front wheels 10 are steered by operating the steering wheel 32. The operator can perform various driving operations in the driver's unit 3.

[0048] The tractor 1 is equipped with a battery 4. The cover member 12 is configured to be swingable about an opening / closing axis Q that extends in the left-right direction of the vehicle body. This allows the cover member 12 to be opened and closed. When the cover member 12 is in a closed state, the battery 4 is covered by the cover member 12.

[0049] The tractor 1 includes an inverter 14 and a motor 40. The motor 40 is located below the battery 4. The motor 40 is also located behind the inverter 14.

[0050] The battery 4 supplies power to the inverter 14. The inverter 14 converts the DC power from the battery 4 into AC power and supplies it to the motor 40. The motor 40 is then driven by the AC power supplied from the inverter 14.

[0051] That is, the tractor 1 is provided with an inverter 14 that converts DC power from the battery 4 into AC power and supplies it to the motor 40.

[0052] As shown in FIG. 1 , the tractor 1 includes a harness 13. The motor 40 also includes a connection portion 41. The connection portion 41 is located at the front of the motor 40. The harness 13 connects the connection portion 41 to the lower end portion of the front of the inverter 14. In other words, the tractor 1 includes the harness 13 that connects the front of the motor 40 to the inverter 14. Power is supplied from the inverter 14 to the motor 40 via the harness 13.

[0053] The tractor 1 is equipped with a hydrostatic continuously variable transmission 15 and a transmission 16. The driving force output from the motor 40 is distributed to the hydrostatic continuously variable transmission 15 and the working device 19. The hydrostatic continuously variable transmission 15 changes the speed of the driving force received from the motor 40 and transmits it to the transmission 16.

[0054] The hydrostatic continuously variable transmission 15 includes a hydraulic pump and a hydraulic motor, and is configured to be able to continuously change the gear ratio. Since the configuration of such a hydrostatic continuously variable transmission 15 is well known, a detailed description of the hydrostatic continuously variable transmission 15 will be omitted.

[0055] The driving force transmitted to the transmission 16 is changed in speed by a gear-type speed change mechanism of the transmission 16 and distributed to the left and right front wheels 10 and the left and right rear wheels 11. In this way, the left and right front wheels 10 and the left and right rear wheels 11 are driven.

[0056] The working device 19 is driven by a driving force from a motor 40. In this embodiment, the working device 19 is specifically a grass cutting device. However, the present invention is not limited to this, and the working device 19 may be, for example, a tilling device or a fertilizing device.

[0057] As shown in FIG. 1 , the aircraft frame 2 includes left and right main frames 20 and a support member 50. The left and right main frames 20 extend in the front-to-rear direction. The support member 50 is a plate-shaped member. The support member 50 is disposed in a position perpendicular to the front-to-rear direction. The front surface of the support member 50 abuts against the rear ends of the left and right main frames 20. The support member 50 is connected to the rear ends of the left and right main frames 20. Although not particularly limited, the support member 50 may be connected to the rear ends of the left and right main frames 20 by, for example, welding.

[0058] The motor 40 is supported by a support member 50. That is, the tractor 1 is provided with the motor 40 that is supported by the support member 50 and is driven by power supplied from the battery 4. As shown in FIG. 5 , the battery 4 is supported by a support frame 35. The support frame 35 is supported by the machine frame 2.

[0059] [Oil pump] As shown in Fig. 2, the tractor 1 is equipped with an oil pump 60. The oil pump 60 is provided on the right side of the machine body. The oil pump 60 is driven by the driving force from the motor 40. The oil pump 60 supplies hydraulic oil to each part of the machine body.

[0060] The structure for transmitting driving force to the oil pump 60 will now be described in detail. As shown in Figures 2 and 5, the motor 40 is cantilevered by the support member 50, with the rear end of the motor 40 supported by the support member 50. The output shaft 42 of the motor 40 passes through the support member 50 and extends rearward. In other words, the motor 40 is cantilevered by the support member 50, with the output shaft 42 of the motor 40 passing through the support member 50 and extending rearward.

[0061] As shown in Fig. 2, a gear case 61 is provided behind the support member 50. A flange portion 43 extending radially outward from the output shaft 42 is formed at the rear end of the motor 40. The flange portion 43, the support member 50, and the gear case 61 are fastened together by a plurality of fasteners 62. That is, the motor 40 is fastened to the support member 50 by the fasteners 62.

[0062] In this embodiment, as shown in Fig. 3, the number of fasteners 62 provided is six. However, the present invention is not limited to this, and the number of fasteners 62 provided may be five or less, or seven or more.

[0063] Furthermore, the fastener 62 in this embodiment is specifically a bolt. However, the present invention is not limited to this. The fastener 62 may be, for example, a bolt and a nut, or may be a rivet.

[0064] 2, a cylindrical member 63 extending in the front-rear direction is attached to the output shaft 42. The output shaft 42 is inserted into the cylindrical member 63. The cylindrical member 63 is disposed in a state in which it penetrates the support member 50 and the gear case 61.

[0065] An input gear 64 is fixed to the cylindrical member 63. The input gear 64 may be formed integrally with the cylindrical member 63, or may be a separate body from the cylindrical member 63.

[0066] The cylindrical member 63 is configured to rotate integrally with the output shaft 42. As a result, the driving force from the output shaft 42 is transmitted to the input gear 64 via the cylindrical member 63.

[0067] 3, the tractor 1 is equipped with four transmission gears 65. The driving force transmitted from the output shaft 42 to the input gear 64 is transmitted to the input shaft 66 of the oil pump 60 via the four transmission gears 65. With this configuration, the oil pump 60 is driven by the driving force from the output shaft 42.

[0068] The input gear 64 and each transmission gear 65 are housed in a space surrounded by the support member 50 and the gear case 61.

[0069] 2, a transmission shaft 67 is connected to the rear end of the cylindrical member 63. The driving force transmitted from the cylindrical member 63 to the transmission shaft 67 is distributed to the hydrostatic continuously variable transmission 15 (see FIG. 1) and the working device 19 (see FIG. 1).

[0070] [Recesses and protrusions] 2 to 4, a recess 52 is formed in the front support surface 51. The front support surface 51 is the front surface of the support member 50. The recess 52 is recessed rearward. That is, the front support surface 51, which is the front surface of the support member 50, is formed with the recess 52 recessed rearward.

[0071] 3, the recess 52 is formed in a ring shape so as to surround a hole (opening) in the support member 50. The output shaft 42 passes through the hole.

[0072] 2 and 4, the motor 40 has a contact surface 44 and a protrusion 45. The contact surface 44 is a vertical surface at the rear end of the motor 40. The contact surface 44 is the rear surface of the motor 40. When the motor 40 is attached to the support member 50, the contact surface 44 comes into contact with the front support surface 51.

[0073] The protruding portion 45 protrudes rearward beyond the contact surface 44. The protruding portion 45 is cylindrical (ring-shaped) and extends in the front-to-rear direction. The output shaft 42 passes through the inside of the protruding portion 45. The protruding portion 45 has a shape that fits into the recessed portion 52. In other words, the motor 40 has the contact surface 44 that comes into contact with the support front surface 51, and the protruding portion 45 that protrudes rearward beyond the contact surface 44 and fits into the recessed portion 52.

[0074] 2 and 4, a ring-shaped collar 68 may be attached to the recess 52. When the motor 40 is attached to the support member 50, the rear end of the protrusion 45 may be in contact with the collar 68.

[0075] 2 and 4, the motor 40 has a housing 46. The housing 46 is formed in a cylindrical shape (approximately cylindrical). The flange portion 43, the contact surface 44, and the protrusion 45 are included in the housing 46.

[0076] The housing 46 is made of a predetermined first material. That is, the protrusion 45 is made of the first material. Although not particularly limited, the first material may be, for example, an aluminum alloy or other metal.

[0077] The support member 50 is made of a predetermined second material. The second material is a material having a higher hardness than the first material. That is, the support member 50 is made of a second material having a higher hardness than the first material. Although not particularly limited, the second material may be, for example, iron or other metals.

[0078] [Positioning mechanism] As shown in Fig. 2, the tractor 1 is provided with a positioning mechanism 7. The positioning mechanism 7 is a mechanism that positions the motor 40 relative to the support member 50 when viewed in the front-rear direction. The positioning mechanism 7 will be described in detail below.

[0079] 2, the positioning mechanism 7 has a plurality of positioning parts 70. Although not particularly limited, it is preferable that the positioning mechanism 7 has three or more positioning parts 70. In this embodiment, the positioning mechanism 7 has three positioning parts 70.

[0080] As shown in Figures 3 and 4, each positioning portion 70 includes one first guide portion 71 and one second guide portion 72 that correspond to each other. In this embodiment, the first guide portion 71 is a pin 8 that extends in the front-rear direction. The second guide portion 72 is a hole portion 9 that fits into the pin 8. The positioning portions 70 have the same structure. The positioning portion 70 shown in Figure 4 is the leftmost positioning portion 70 of the three positioning portions 70 shown in Figures 2 and 3.

[0081] As shown in FIG. 4 , the pin 8 is attached to the motor 40. The hole 9 is provided in the support member 50. That is, in this embodiment, the first guide portion 71 is provided in the motor 40, and the second guide portion 72 is provided in the support member 50. However, the present invention is not limited to this, and the first guide portion 71 (pin 8) may be provided in the support member 50, and the second guide portion 72 (hole 9) may be provided in the motor 40.

[0082] The positioning mechanism 7 is configured to position the motor 40 relative to the support member 50 in a front-to-rear view by abutting the first guide portion 71 and the second guide portion 72 against each other. More specifically, the positioning mechanism 7 is configured to position the motor 40 relative to the support member 50 in a front-to-rear view by fitting the pins 8 into the holes 9 against each other. In this specification, "fitting" is a specific example of "abutting."

[0083] That is, the tractor 1 has a first guide portion 71 provided on one of the motor 40 and the support member 50, and a second guide portion 72 provided on the other of the motor 40 and the support member 50, and is equipped with a positioning mechanism 7 that positions the motor 40 relative to the support member 50 when viewed in the forward / backward direction by the first guide portion 71 and the second guide portion 72 abutting against each other.

[0084] As a result of positioning by the positioning mechanism 7, the shaft core 42a of the output shaft 42 is positioned at the center of the hole (opening) surrounded by the recess 52 when viewed in the front-rear direction, as shown in FIG.

[0085] Also shown in Figure 3 is a triangle T. The three vertices of the triangle T are the positions of the three positioning portions 70 when viewed in the front-to-rear direction. In this embodiment, as shown in Figure 3, the triangle T is not an equilateral triangle. That is, the three positioning portions 70 are arranged so that the triangle T, whose vertices are the positions of the three positioning portions 70, is not an equilateral triangle when viewed in the front-to-rear direction.

[0086] 3, two of the three positioning portions 70 are arranged above the shaft center 42a. The remaining one of the three positioning portions 70 is arranged below the shaft center 42a. That is, the multiple positioning portions 70 are arranged above and below the shaft center 42a of the output shaft 42. Furthermore, of the multiple positioning portions 70, the number of positioning portions 70 arranged above the shaft center 42a is greater than the number of positioning portions 70 arranged below the shaft center 42a.

[0087] 3 also shows an arrangement circle E. The arrangement circle E is a circle whose center is the shaft core 42a when viewed in the front-rear direction. Each fastener 62 is arranged on the arrangement circle E. Each positioning portion 70 is located inside the arrangement circle E. In other words, in the radial direction of the output shaft 42, the positioning portion 70 is located on the inner peripheral side of the fastener 62.

[0088] 4, the pin 8 is attached to a pin attachment surface P, which is one of the front support surface 51 and the abutment surface 44. In this embodiment, the pin attachment surface P is the abutment surface 44. That is, the pin 8 is attached to the abutment surface 44. The pin 8 protrudes rearward from the pin attachment surface P.

[0089] However, the present invention is not limited to this, and the pin mounting surface P may be the front support surface 51. In this case, the pin 8 protrudes forward from the pin mounting surface P. Also, in this case, the hole 9 may be provided in the motor 40.

[0090] That is, the pin 8 is attached to a pin attachment surface P, which is one of the support front surface 51 and the abutment surface 44, and protrudes from the pin attachment surface P forward or backward.

[0091] As shown in FIG. 4, the pin 8 has a tapered portion 81 and a main body portion 83. The tapered portion 81 is formed at the protruding end of the pin 8. That is, the tapered portion 81 is formed at the protruding end of the pin 8. The tapered portion 81 is formed so that the diameter decreases toward the tip. The main body portion 83 is formed in a cylindrical shape. The diameter of the main body portion 83 is the same as the diameter of the base end 81a of the tapered portion 81. In addition, the diameter of the main body portion 83 is approximately the same as the diameter of the hole portion 9. The front end (root portion) of the main body portion 83 is fixed in a state embedded in the motor 40. In addition, FIG. 4 shows a first length L1, a second length L2, and a third length L3.

[0092] The first length L1 is the protruding length of the protruding portion 45. In other words, the first length L1 is the length from the contact surface 44 to the rear end of the protruding portion 45 in the front-rear direction.

[0093] The second length L2 is the length from the pin attachment surface P to the base end 81a of the tapered portion 81 in the front-rear direction.

[0094] The third length L3 is the length from the pin attachment surface P to the protruding end 82 of the pin 8 in the front-rear direction.

[0095] 4, the second length L2 is longer than the first length L1. The third length L3 is longer than the second length L2. That is, the third length L3 is longer than the first length L1.

[0096] That is, the length from the pin mounting surface P to the protruding end 82 of the pin 8 is longer than the protruding length of the protruding portion 45. Also, the length from the pin mounting surface P to the base end 81a of the tapered portion 81 is longer than the protruding length of the protruding portion 45.

[0097] Fig. 4 shows the motor 40 when it is attached to the support member 50. Note that the output shaft 42 is omitted from Fig. 4. Fig. 4 also shows a first position Q1 and a second position Q2. Both the first position Q1 and the second position Q2 are positions forward of the support front surface 51. The first position Q1 is a position forward of the second position Q2.

[0098] When the motor 40 is attached to the support member 50, and the rear end of the protruding portion 45 is located at the first position Q1, the position of the protruding end 82 of the pin 8 in the front-rear direction coincides with the position of the front support surface 51 in the front-rear direction. In other words, when the motor 40 is attached to the support member 50, the pin 8 begins to enter the hole 9 when the rear end of the protruding portion 45 reaches the first position Q1. At this point, the rear end of the protruding portion 45 is located forward of the front support surface 51. In other words, at this point, the protruding portion 45 has not yet begun to fit into the recess 52.

[0099] Then, when the motor 40 moves even closer to the support member 50, and the rear end of the protrusion 45 is positioned rearward of the first position Q1 and forward of the second position Q2, the pin 8 is able to come into contact with the hole 9. For example, if the position of the motor 40 in the left-right direction is shifted from the appropriate position at this time, the pin 8 will come into contact with the hole 9. As a result, the positional shift of the motor 40 in the left-right direction is prevented from becoming too great.

[0100] At this time, the pin 8 and the hole 9 can come into contact with each other with the rear end of the protrusion 45 positioned forward of the front support surface 51. In other words, the positioning mechanism 7 is configured such that when the motor 40 is attached to the support member 50, the first guide portion 71 and the second guide portion 72 can come into contact with each other with the protrusion 45 positioned forward of the front support surface 51.

[0101] Then, when the motor 40 moves further closer to the support member 50 and the rear end of the protrusion 45 reaches the second position Q2, the position of the base end 81a in the front-rear direction coincides with the position of the front support surface 51 in the front-rear direction, as shown by the imaginary line in FIG. 4 . That is, when the motor 40 is attached to the support member 50, the main body 83 begins to enter the hole 9 when the rear end of the protrusion 45 reaches the second position Q2. In other words, when the motor 40 is attached to the support member 50, the main body 83 of the pin 8 begins to fit into the hole 9 when the rear end of the protrusion 45 reaches the second position Q2. At this point, the rear end of the protrusion 45 is located forward of the front support surface 51. That is, at this point, the protrusion 45 has not yet begun to fit into the recess 52.

[0102] Then, as the motor 40 moves further closer to the support member 50 , the protrusion 45 fits into the recess 52 .

[0103] According to the configuration described above, when the motor 40 is attached to the support member 50, the first guide portion 71 and the second guide portion 72 come into contact with each other before the protrusion 45 fits into the recess 52. This allows the motor 40 to be positioned. Furthermore, by moving the motor 40 rearward while the first guide portion 71 and the second guide portion 72 remain in contact with each other, the protrusion 45 can be fitted into the recess 52 with the motor 40 positioned relative to the support member 50 in the front-to-rear direction. This makes it less likely that the surface of the protrusion 45 will be scratched than when the protrusion 45 is fitted into the recess 52 with the motor 40 not positioned relative to the support member 50 in the front-to-rear direction (with the motor 40 able to move freely relative to the support member 50 in the front-to-rear direction).

[0104] Moreover, with the configuration described above, the motor 40 is attached to the support member 50 from the front, and the harness 13 connecting the motor 40 and the inverter 14 is connected to the front of the motor 40. Therefore, compared to when the harness 13 is connected to the rear of the motor 40, the connection portion 41 of the harness 13 in the motor 40 and the harness 13 itself are less likely to interfere with the attachment of the motor 40 to the support member 50.

[0105] In other words, with the configuration described above, when the motor 40 is attached to the support member 50, the attachment work can be carried out smoothly, the motor 40 can be positioned, and a tractor 1 can be realized in which scratches on the surface of the motor 40 can be easily avoided.

[0106] Other Embodiments (1) As long as it is possible to position the motor 40 relative to the support member 50 when viewed in the front-rear direction, the first guide portion 71 does not have to be a pin 8, and the second guide portion 72 does not have to be a hole 9. For example, the first guide portion 71 and the second guide portion 72 may be configured by rails and rollers guided by the rails.

[0107] (2) The number of positioning parts 70 that the positioning mechanism 7 has may be one.

[0108] (3) Triangle T may be an equilateral triangle.

[0109] (4) All of the positioning portions 70 may be disposed above the axis 42a, or may be disposed below the axis 42a.

[0110] (5) Of the multiple positioning portions 70, the number of positioning portions 70 arranged above the axis 42a may be less than the number of positioning portions 70 arranged below the axis 42a, or may be equal to the number of positioning portions 70 arranged below the axis 42a.

[0111] (6) The pin 8 does not have to have the tapered portion 81 formed thereon.

[0112] (7) In the radial direction of the output shaft 42, the positioning portion 70 may be located on the outer circumferential side of the fastener 62.

[0113] (8) The positioning portion 70 may be disposed on the arrangement circle E.

[0114] (9) The positions and shapes of the protrusions 45 and recesses 52 can be changed as needed.

[0115] (10) As shown in Fig. 6, the support structure of the motor 40 may not be cantilevered. In the example shown in Fig. 6, a connecting portion 47 and a connecting bolt 48 are provided. The connecting portion 47 is formed by bending a plate material into a channel shape. The connecting portion 47 is connected to the lower surface of the support frame 35 in a state where it protrudes downward from the lower surface of the support frame 35. The lower surface of the connecting portion 47 contacts the upper end of the housing 46.

[0116] A connecting bolt 48 extending in the vertical direction connects the connecting portion 47 to the upper end of the housing 46. With this structure, the motor 40 is supported by the connecting portion 47 and the support member 50.

[0117] An opening 49 is formed in the support frame 35 at a location above the connecting bolt 48. An operator can insert a tool such as a wrench into the opening 49 to tighten or loosen the connecting bolt 48.

[0118] The configurations disclosed in the above-described embodiments (including other embodiments, the same applies hereinafter) can be applied in combination with the configurations disclosed in other embodiments, unless a contradiction arises. Furthermore, the embodiments disclosed in this specification are merely examples, and the present invention is not limited to these, and can be modified as appropriate within the scope of the purpose of the present invention. [Industrial Applicability]

[0119] The present invention can be used not only in tractors but also in various electric work vehicles such as combine harvesters, rice transplanters, and construction machines. [Explanation of symbols]

[0120] 1: Tractor (electric work vehicle) 4: Battery 7: Positioning mechanism 8: Pin 9: Hole 13: Harness 14: Inverter 40: Motor 42: Output shaft 42a: Axis core 44: Contact surface 45:Protrusion 50: Support member 51: Support front 52: Recess 62: Fasteners 70: Positioning section 71: First guide section 72: Second guide section 81: Tapered section 81a: proximal end 82:Protruding end P: Pin mounting surface T: Triangle

Claims

1. A battery, a motor supported by a support member and driven by power supplied from the battery; an inverter that converts DC power from the battery into AC power and supplies the AC power to the motor; a harness connecting a front portion of the motor and the inverter, power is supplied from the inverter to the motor via the harness; the motor is supported by the support member with an output shaft of the motor passing through the support member and extending rearward; A recess recessed toward the rear is formed on the front support surface, which is the front surface of the support member, the motor has a contact surface that contacts the support front surface, and a protrusion that protrudes rearward from the contact surface and fits into the recess, the protrusion is made of a first material; the support member is made of a second material having a higher hardness than the first material; a positioning mechanism including a first guide portion provided on one of the motor and the support member, and a second guide portion provided on the other of the motor and the support member, and which positions the motor with respect to the support member when viewed in the front-rear direction by contact between the first guide portion and the second guide portion; The positioning mechanism is an electric work vehicle configured so that when the motor is attached to the support member, the first guide portion and the second guide portion can abut against each other with the protrusion positioned forward of the support front surface.

2. the first guide portion is a pin extending in the front-rear direction, the second guide portion is a hole portion that fits onto the pin, the positioning mechanism has a plurality of positioning portions, The electric work vehicle according to claim 1 , wherein each of the positioning portions includes one of the first guide portions and one of the second guide portions that correspond to each other.

3. The electric work vehicle according to claim 2 , wherein the positioning mechanism has three or more positioning parts.

4. the positioning mechanism has three of the positioning portions, 4. The electric work vehicle according to claim 2, wherein the three positioning parts are arranged so that, when viewed from the front to rear, a triangle having vertices at the positions of the three positioning parts is not an equilateral triangle.

5. 4. The electric work vehicle according to claim 2, wherein the plurality of positioning portions are arranged above and below the axis of the output shaft.

6. The electric work vehicle according to claim 5, wherein the number of the positioning parts arranged above the shaft core is greater than the number of the positioning parts arranged below the shaft core.

7. the pin is attached to a pin attachment surface, which is one of the support front surface and the abutment surface, and protrudes forward or rearward from the pin attachment surface; 4. The electric work vehicle according to claim 2 or 3, wherein the length from the pin mounting surface to the protruding end of the pin is longer than the protruding length of the protruding portion.

8. A tapered portion is formed at the protruding end of the pin, The electric work vehicle according to claim 7 , wherein the length from the pin attachment surface to the base end of the tapered portion is longer than the protruding length of the protruding portion.

9. the pin is attached to the motor; The electric work vehicle according to claim 2 or 3, wherein the hole is provided in the support member.

10. the motor is fastened to the support member by a fastener; The electric work vehicle according to claim 2 or 3, wherein the positioning portion is located radially inward of the fastener in the radial direction of the output shaft.

11. The electric work vehicle according to any one of claims 1 to 3, wherein the motor is supported by the support member in a cantilevered manner.

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