JP7645784B2 - Electric work vehicle - Google Patents

Description

The present invention relates to an electric work vehicle.

For example, the electric work vehicle disclosed in Patent Document 1 has an inverter located adjacent to and below the battery, and the inverter is configured to convert DC power from the battery into AC power and supply it to the motor.

JP 2021-000957 A

In a configuration where the battery and inverter are adjacent to each other, the conductive cable that supplies power from the battery to the inverter can be easily shortened. On the other hand, it is possible that the wiring may become congested at the connection port on the inverter side of the conductive cable between the battery and inverter, so it is desirable to have a configuration in which the conductive cable that supplies power from the inverter to the motor can be wired efficiently while avoiding such congestion as much as possible.

The object of the present invention is to provide an electric work vehicle that is configured to efficiently wire conductive cables between the inverter and the motor.

The electric work vehicle of the present invention is an electric work vehicle that does not have an internal combustion engine, and in which a traveling device and a working device are driven by an electric motor, and is provided with a body, a traveling device having front wheels and rear wheels and for traveling the body, an axle unit supporting the front wheels, an operating mechanism for transmitting power to the working device, a motor for rotating and driving at least one of the traveling device and the operating mechanism, a battery for supplying power to the motor, an inverter for converting direct current from the battery into alternating current and supplying the current to the motor, and a conductive cable electrically connected to each of the inverter and the motor for conducting the alternating current to the motor, The inverter has an inverter module that converts the direct current into the alternating current, a case that houses the inverter module, and a first connector that protrudes outward from a surface of the case and is electrically connected to the conductive cable, wherein the battery and the inverter are arranged adjacent to each other, and the first connector is provided in a state where it protrudes from the surface of the case opposite the side on which the battery is located to the opposite side, and is located on the front wheel side between the front wheels and the rear wheels, and is located between the axle unit and the battery in the vertical direction of the vehicle body .

In the present invention, the inverter and motor are electrically connected by connecting the conductive cable to the first connector, and the first connector protrudes from the surface portion opposite the side where the battery is located. In a configuration in which the battery and the inverter are adjacent to each other, it is possible that the wiring from the battery may become congested in the area of the inverter on the side where the battery is located. For this reason, compared to a configuration in which the first connector is arranged in an area close to the side where the battery is located, it is easier to configure the conductive cable to be freely wired while avoiding such congestion. This realizes an electric work vehicle configured to efficiently wire the conductive cable between the inverter and the motor.

The electric work vehicle of the present invention comprises a body, a traveling device that travels the body, an operating mechanism for transmitting power to a work device, a motor that rotates and drives at least one of the traveling device and the operating mechanism, a battery that supplies power to the motor, an inverter that converts direct current from the battery into alternating current and supplies it to the motor, and a conductive cable that is electrically connected to each of the inverter and the motor and conducts the alternating current to the motor, the inverter has an inverter module that converts the direct current into the alternating current, a case that houses the inverter module, and a first connector that protrudes outward from a surface of the case and is electrically connected to the conductive cable, the battery and the inverter are arranged adjacent to each other, the first connector is provided in a state where it protrudes from the surface of the case opposite to the side on which the battery is located to the opposite side, the inverter and the motor are arranged adjacent to each other, and the first connector is provided in a state where it is located in an area of the case opposite to the side on which the motor is located.

In the present invention, the conductive cable is connected to the first connector, so that the inverter and the motor are electrically connected, and the first connector protrudes from the surface portion opposite to the side where the battery is located. In a configuration in which the battery and the inverter are adjacent to each other, it is possible that wiring from the battery may become crowded in the area of the inverter on the side where the battery is located. Therefore, compared with a configuration in which the first connector is arranged in an area close to the side where the battery is located, it is easier to freely wire the conductive cable while avoiding the congestion . It is considered that a large current flows through the conductive cable between the inverter and the motor. Therefore, the diameter of the conductive cable tends to be thicker than that of a general wiring cable, and it is also considered that the conductive cable is difficult to bend. With this configuration, since the first connector is provided at a position as far away from the motor as possible, even if the diameter of the conductive cable is thick, the conductive cable is connected to the inverter and the motor in a gently bent state. This realizes an electric work vehicle configured to efficiently wire the conductive cable between the inverter and the motor.

The electric work vehicle of the present invention comprises a body, a traveling device that travels the body, an operating mechanism for transmitting power to a working device, a motor that rotates and drives at least one of the traveling device and the operating mechanism, a battery that supplies power to the motor, an inverter that converts direct current from the battery into alternating current and supplies it to the motor, and a conductive cable that is electrically connected to each of the inverter and the motor and conducts the alternating current to the motor, the inverter has an inverter module that converts the direct current into the alternating current, a case that houses the inverter module, and a first connector that protrudes outward from a surface of the case and is electrically connected to the conductive cable, the battery and the inverter are arranged adjacent to each other, the first connector is provided in a state where it protrudes from the surface of the case opposite the side on which the battery is located to the opposite side, the motor has a second connector that connects to the conductive cable, and the first connector and the second connector are arranged facing each other.

In the present invention, the inverter and the motor are electrically connected by connecting the conductive cable to the first connector, and the first connector protrudes from the surface portion opposite the side where the battery is located to the opposite side. In a configuration in which the battery and the inverter are adjacent to each other, it is possible that wiring from the battery may become congested in the area of the inverter on the side where the battery is located. Therefore, compared to a configuration in which the first connector is disposed in an area close to the side where the battery is located, it is easier to configure the conductive cable to be freely wired while avoiding such congestion. Furthermore, this configuration makes it easier for the conductive cable to be connected to the inverter and the motor. This realizes an electric work vehicle configured to efficiently wire the conductive cable between the inverter and the motor.

In the present invention, it is preferable that the inverter and the motor are arranged side by side along the fore-and-aft direction of the aircraft, the first connector and the second connector are arranged with a left-right positional shift when viewed in the fore-and-aft direction of the aircraft, and the first connector is provided in a state in which it is inclined toward the side where the second connector is located with respect to the fore-and-aft direction of the aircraft.

This configuration makes it easier to connect the conductive cable to the inverter and the motor even if the first connector and the second connector are not precisely aligned.

The electric work vehicle of the present invention comprises a vehicle body, a traveling device for traveling the vehicle body, an operating mechanism for transmitting power to a working device, a motor for rotating at least one of the traveling device and the operating mechanism, a battery for supplying power to the motor, an inverter for converting direct current from the battery into alternating current and supplying the alternating current to the motor, and a conductive cable electrically connected to each of the inverter and the motor for conducting the alternating current to the motor, the inverter comprising an inverter module for converting the direct current into the alternating current, a case for housing the inverter module, and a conductive cable for connecting the inverter module to the motor and the motor, the conductive cable being electrically connected to the inverter module and the motor and the inverter module being electrically connected to the motor and the motor. and a first connector extending from the surface portion of the case opposite to the side on which the battery is located, the first connector being provided so as to protrude to the opposite side, the aircraft having left and right aircraft frames extending in a fore-and-aft direction, the battery being placed and supported on the left and right aircraft frames in a state where it is located directly above the inverter, the motor and the inverter being supported by the left and right aircraft frames in a state where they are lined up along the fore-and-aft direction of the aircraft and located between the left and right aircraft frames, and the conductive cable being housed in the space between the left and right aircraft frames.

In the present invention, the conductive cable is connected to the first connector, so that the inverter and the motor are electrically connected, and the first connector protrudes from the surface portion opposite to the side where the battery is located. In a configuration in which the battery and the inverter are adjacent to each other, it is possible that wiring from the battery may become crowded in the area of the inverter on the side where the battery is located. Therefore, compared with a configuration in which the first connector is arranged in an area close to the side where the battery is located, it is easier to configure the conductive cable to be freely wired while avoiding such congestion. In addition, with this configuration, the conductive cable is accommodated in the space between the left and right machine frames, so the space between the left and right machine frames is effectively utilized. In addition, since the machine frames are present on the left and right of the conductive cable, foreign objects are less likely to come into contact with the conductive cable. This realizes an electric work vehicle configured to efficiently wire the conductive cable between the inverter and the motor.

In the present invention, it is preferable that the inverter is detachably supported on the left and right aircraft frames.

This configuration improves the maintainability of the inverter compared to a configuration in which the inverter cannot be attached or detached from the left and right aircraft frames.

In the present invention, the aircraft has a horizontal frame that connects the left and right aircraft frames, and the conductive cable is preferably located above the horizontal frame.

With this configuration, the conductive cable is housed within a space surrounded by the left and right aircraft frames and the horizontal frame, making it even more difficult for foreign objects to come into contact with the conductive cable.

In the present invention, it is preferable that the inverter is located in front of the motor, and the horizontal frame is connected to the left and right body frames at the lower parts of the left and right body frames, and extends back and forth across the area where the front end of the inverter is located and the area where the front end of the motor is located in a plan view.

With this configuration, the horizontal frame is present across the area where the conductive cable is located, making it even more difficult for foreign objects to come into contact with the conductive cable.

FIG. FIG. 4 is a left side view showing the arrangement of an inverter and the like. FIG. FIG. 2 is a cross-sectional view of the machine frame and shows wiring around the inverter. FIG. 2 is a cross-sectional view of the machine frame and shows wiring around the inverter. 2 is a plan view showing the inside of an inverter and the periphery of the inverter; FIG. FIG. 13 is a diagram showing a locking mechanism for wiring to an inverter. FIG. 13 is a diagram showing a locking mechanism for wiring to an inverter. FIG. 13 is a diagram showing a locking mechanism for wiring to an inverter. 13A and 13B are views showing a vibration-isolating member for a first conductive part. 13A and 13B are views showing a vibration-isolating member for a second conductive part.

The embodiment for carrying out the present invention will be explained with reference to the drawings. In the following explanation, unless otherwise specified, the direction of the arrow F in the figure is "forward", the direction of the arrow B is "backward", the direction of the arrow L is "left", and the direction of the arrow R is "right". In addition, the direction of the arrow U in the figure is "up" and the direction of the arrow D is "down".

[Overall configuration of the tractor]
The tractor of this embodiment will be described below. As shown in FIG. 1, the tractor has left and right front wheels 10, left and right rear wheels 11, and a cover member 12.

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

The cover member 12 is disposed at the front of the aircraft. 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.

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 board 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.

The tractor is equipped with a driving battery 4. The cover member 12 is configured to be able to swing around an opening/closing axis Q that runs along 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 driving battery 4 is covered by the cover member 12.

As shown in FIG. 2, the tractor is equipped with an inverter 14 and a motor M. The driving battery 4 supplies power to the inverter 14. The inverter 14 converts DC power from the driving battery 4 into AC power and supplies it to the motor M. The motor M is then driven by the AC power supplied from the inverter 14.

As shown in Figures 2 and 3, the tractor is equipped with a hydrostatic continuously variable transmission 15 and a transmission 16. As shown in Figure 3, the hydrostatic continuously variable transmission 15 has a hydraulic pump 15a and a hydraulic motor 15b.

The hydraulic pump 15a is driven by the rotational power from the motor M. When the hydraulic pump 15a is driven, the rotational power is output from the hydraulic motor 15b. The hydrostatic continuously variable transmission 15 is configured so that the rotational power is changed between the hydraulic pump 15a and the hydraulic motor 15b. The hydrostatic continuously variable transmission 15 is also configured so that the gear ratio can be changed steplessly.

The rotational power output from the hydraulic motor 15b is transmitted to the transmission 16. The rotational power 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. This drives the left and right front wheels 10 and the left and right rear wheels 11.

As shown in Figures 2 and 3, the tractor is equipped with a mid PTO shaft 17 and a rear PTO shaft 18. The rotational power output from the motor M is distributed to the hydraulic pump 15a, the mid PTO shaft 17, and the rear PTO shaft 18. This causes the mid PTO shaft 17 and the rear PTO shaft 18 to rotate.

If a working device is connected to the mid-PTO shaft 17 or the rear PTO shaft 18, the working device is driven by the rotational power of the mid-PTO shaft 17 or the rear PTO shaft 18. For example, as shown in FIG. 2, in this embodiment, a grass cutting device 19 is connected to the mid-PTO shaft 17. The grass cutting device 19 is driven by the rotational power of the mid-PTO shaft 17.

The mid PTO shaft 17 and rear PTO shaft 18 correspond to the "operating mechanism" of the present invention. The grass cutting device 19 corresponds to the "working device" of the present invention. The left and right front wheels 10 and the left and right rear wheels 11 correspond to the "traveling device" of the present invention.

[Inverter and wiring around the inverter]
The inverter 14 and peripheral wiring of this embodiment will be described with reference to Figures 4 to 6. The inverter 14 converts direct current from the driving battery 4 into alternating current and supplies it to the motor M.

As shown in FIG. 6, the inverter 14 is equipped with a capacitor 41 and an inverter module 42. The capacitor 41 and the inverter module 42 are electrically connected. The inverter module 42 is a circuit body that converts direct current from the driving battery 4 into alternating current, and is, for example, an insulated gate bipolar transistor (IGBT). The capacitor 41 keeps the supply voltage to the inverter module 42 constant. The inverter 14 has a case 14A, and the capacitor 41 and the inverter module 42 are housed in the case 14A. The case 14A is made by die casting of aluminum.

The driving battery 4 and the inverter 14 are electrically connected by a power cable 20. A direct current flows through the power cable 20. As shown in Figures 4 and 6, the inverter 14 is provided with an input connector 14B, which protrudes forward from the front surface of the case 14A and is electrically connected to the connection port 20A of the power cable 20.

As shown in Figures 4 and 5, the inverter 14 and the motor M are electrically connected by a power supply cable 21. Three-phase AC current flows through the power supply cable 21. In other words, the power supply cable 21 is electrically connected to each of the inverter 14 and the motor M, and conducts AC current to the motor M. The inverter 14 is provided with an output connector 14C, which protrudes below the bottom surface of the case 14A and is electrically connected to the connection port 21A of the power supply cable 21. The motor M has a power receiving connector 22, which is electrically connected to the connection port 21B of the power supply cable 21.

As shown in FIG. 6, the inverter 14 has a first conductive part 43 and a second conductive part 44. The first conductive part 43 has two bus bars 43A, 43B for conducting DC current from the input connector 14B to the capacitor 41. The second conductive part 44 has three bus bars 44A, 44B, 44C for conducting AC current from the inverter module 42 to the output connector 14C. Three-phase AC currents of U, V, and W are passed through each of the three bus bars 44A, 44B, and 44C in the second conductive part 44. A clamp-type current sensor 47 is disposed in the longitudinal center of each of the three bus bars 44A, 44B, and 44C.

Thus, the inverter 14 has an input connector 14B that is electrically connected to the power cable 20, an inverter module 42 that converts DC current to AC current, and an output connector 14C that is electrically connected to the power supply cable 21.

The output connector 14C corresponds to the "first connector" of the present invention. The power receiving connector 22 corresponds to the "second connector" of the present invention. The power supply cable 21 corresponds to the "conductive cable" of the present invention.

As shown in Figures 4 and 5, the aircraft frame 2 has left and right front-rear frames 2A and a horizontal frame 2B. The left and right front-rear frames 2A extend along the front-rear direction of the aircraft, and the horizontal frame 2B connects the left and right front-rear frames 2A to each other. The horizontal frame 2B connects the left and right front-rear frames 2A at the lower parts of the left and right front-rear frames 2A, and extends in the front-rear direction across the area where the front end of the inverter 14 is located and the area where the front end of the motor M is located in a plan view. The left and right front-rear frames 2A correspond to the "left and right aircraft frames" in this invention.

The axle unit 10F is connected to the horizontal frame 2B and extends to the left and right of the vehicle. The front wheels 10 are rotatably supported at both the left and right ends of the axle unit 10F. A propeller shaft 26 is connected to the transmission 16 and the axle unit 10F and extends in the fore-and-aft direction of the vehicle below the horizontal frame 2B.

The inverter 14 and the motor M are arranged adjacent to each other in the fore-and-aft direction. In other words, the inverter 14 and the motor M are arranged side by side along the fore-and-aft direction of the aircraft. The motor M and the inverter 14 are supported by the left and right front-and-aft frames 2A side by side along the fore-and-aft direction of the aircraft and positioned between the left and right front-and-aft frames 2A. The inverter 14 is located in front of the motor M.

The output connector 14C and the power receiving connector 22 are arranged facing each other. The output connector 14C is provided in a state in which it is located in an area of the case 14A opposite the side where the motor M is located. The power supply cable 21 is located above the horizontal frame 2B and is housed in the space between the left and right front and rear frames 2A. In other words, the power supply cable 21 extends forward and backward within the space surrounded by the left and right front and rear frames 2A, the horizontal frame 2B, and the bottom surface of the case 14A. This prevents the output connector 14C and the power supply cable 21 from coming into contact with foreign objects, and also reduces the risk of the output connector 14C and the power supply cable 21 coming into contact with foreign objects and becoming disconnected.

As shown in FIG. 5, line L11 indicating the center in the left-right direction of connection port 21B and power receiving connector 22 and line L12 indicating the center in the left-right direction of connection port 21A and output connector 14C are misaligned left-right. In other words, output connector 14C and power receiving connector 22 are arranged facing each other and misaligned left-right when viewed in the front-to-rear direction of the aircraft. For this reason, output connector 14C is arranged in a state in which it is tilted toward the side where power receiving connector 22 is located with respect to the front-to-rear direction of the aircraft.

As shown in FIG. 6, the three bus bars 44A, 44B, and 44C in the second conductive portion 44 are arranged at equal or approximately equal intervals so as to be aligned on line L13. Line L13 is inclined relative to the lateral direction of the aircraft. This makes it possible to configure the output connector 14C to be inclined toward the side where the power receiving connector 22 is located.

The driving battery 4 is mounted and supported on the left and right front and rear frames 2A, positioned directly above the inverter 14. Specifically, as shown in Figures 4 to 6, left and right support surface portions 23 are formed on the upper end portions of the left and right front and rear frames 2A. A mounting frame 24 is placed on the left and right support surface portions 23, and the driving battery 4 is placed on the mounting frame 24.

The left and right support surface portions 23 extend laterally of the aircraft at the upper ends of the left and right front and rear frames 2A. As shown in Figures 4 and 5, triangular ribs 27A, 27B, 27C, and 27D are interposed between the support surface portions 23 and the front and rear frames 2A to prevent the left and right support surface portions 23 from bending relative to the left and right front and rear frames 2A, and the support surface portions 23 are reinforced by the triangular ribs 27A, 27B, 27C, and 27D. The bottom of the inverter 14 and the support surface portions 23 are connected by bolts. As a result, the inverter 14 is supported removably on the left and right front and rear frames 2A.

The mounting platform frame 24 is connected to the left and right support surface portions 23 with bolts. As shown in Figures 4 to 6, the mounting platform frame 24 is a member assembled by welding a vertical frame 24A of C-shaped steel erected on the left and right support surface portions 23, left and right angle steels 24B extending in the fore-and-aft direction of the machine body at the upper ends of the left and right vertical frames 24A, and a horizontal angle steel (not shown) connecting the left and right angle steels 24B extending in the fore-and-aft direction of the machine body. The mounting platform frame 24 is formed in a C-shape when viewed in the fore-and-aft direction of the machine body. The mounting platform frame 24 covers the inverter 14 from above and from the left and right sides.

Bolts are used to connect the left and right sides of the upper part of the angle steel 24B to the lower part of the connecting plate 25. Also, bolts are used to connect the left and right sides of the lower part of the driving battery 4 to the upper part of the connecting plate 25. This connects the inverter 14 and the mounting frame 24 via the connecting plate 25.

The driving battery 4 and the inverter 14 are arranged adjacent to each other in the vertical direction. Thus, the output connector 14C is provided in a state where it protrudes from the surface of the case 14A on the side opposite to the side where the driving battery 4 is located.

[Lock mechanism for wiring to inverter]
In this embodiment, the connection port 20A of the power cable 20 and the connection port 21A of the power supply cable 21 are each provided with a rotating member 35 and a sliding member 36 as a locking mechanism. An arc-shaped long hole 35h is formed in the rotating member 35. A protruding locking portion 37 is inserted into the long hole 35h. The protruding locking portion 37 is formed in each of the input connector 14B and the output connector 14C of the inverter 14, and protrudes outward from the connector body.

As shown in Figures 7 and 8, the rotating member 35 is configured to be rotatable around the axis X. Figure 7 shows a state in which the connection port 20A is not engaged with the input connector 14B, or a state in which the connection port 21A is not engaged with the output connector 14C. The state of the rotating member 35 at this time is called the "non-engagement position." With the rotating member 35 in the non-engagement position, the protruding engagement portion 37 can be removed from the long hole 35h.

Figure 8 shows a state in which connection port 20A is engaged with input connector 14B, or a state in which connection port 21A is engaged with output connector 14C. The state of rotating member 35 at this time is called the "engaged position." When an operator rotates rotating member 35 in the direction of the arrow in Figure 7, rotating member 35 is switched from the non-engaged position to the engaged position.

One end of the long hole 35h is formed to be closer to the axis X than the other end of the long hole 35h. The long hole 35h is formed to be closer to the axis X on the side where the one end is located. Therefore, when the rotating member 35 rotates to the engagement position side, the protruding locking portion 37 slides inside the long hole 35h toward the one end, and the connection port 20A and the input connector 14B (or the connection port 21A and the output connector 14C) approach each other and are firmly connected.

When an operator rotates the rotating member 35 in the direction opposite to the arrow in FIG. 7, the rotating member 35 is switched from the engaged position to the disengaged position. At this time, when the rotating member 35 rotates toward the disengaged position, the protruding locking portion 37 slides inside the long hole 35h toward the other end, and the connection port 20A and the input connector 14B (or the connection port 21A and the output connector 14C) are separated. Then, when the protruding locking portion 37 comes out of the long hole 35h with the rotating member 35 in the disengaged position, the connection between the connection port 20A and the input connector 14B (or the connection port 21A and the output connector 14C) is released.

In this manner, the rotating member 35 is configured to rotate between an engagement position in which it engages with the input connector 14B and a disengagement position in which it does not engage with the input connector 14B.

The slide member 36 is configured to slide between a holding position where the rotating member 35 is held in the engaged position and a non-holding position where the rotating member 35 is not held in the engaged position. As shown in Figure 9, when an operator slides the slide member 36 in the direction of the arrow shown in Figure 9, the rotating member 35 and the slide member 36 engage with each other, and the rotating member 35 becomes unable to rotate while holding the engaged position. The position of the slide member 36 at this time is the holding position.

When the operator slides the slide member 36 in the direction opposite to the arrow shown in FIG. 9, the engagement between the rotating member 35 and the slide member 36 is released, and the rotating member 35 can be rotated to the non-engaged position. The position of the slide member 36 at this time is the non-retained position.

[Vibration-proof structure of busbars in inverters]
As described above, the inverter 14 has the first conductive part 43 and the second conductive part 44. The first conductive part 43 has two bus bars 43A and 43B for conducting DC current from the input connector 14B to the capacitor 41. The second conductive part 44 has three bus bars 44A, 44B, and 44C for conducting AC current from the inverter module 42 to the output connector 14C. Each of the bus bars 43A, 43B, 44A, 44B, and 44C is made of a long metal flat plate. Both ends in the longitudinal direction of each of the bus bars 43A, 43B, 44A, 44B, and 44C are fixed by bolts.

As shown in Figures 6 and 10, the bus bars 43A and 43B in the first conductive part 43 are bolted to the input connector 14B and the terminals 41A and 41B of the capacitor 41, respectively. As shown in Figures 6 and 11, the bus bars 44A, 44B, and 44C in the second conductive part 44 are bolted to the output connector 14C and the inverter module 42, respectively.

The input connector 14B and the output connector 14C each protrude outward beyond the outer surface of the case 14A. For this reason, when vibrations occur, the vibrations of the input connector 14B and the output connector 14C may tend to be greater than the vibrations of the case 14A. In this case, the vibrations of the input connector 14B are transmitted to the bus bars 43A and 43B, and the vibrations of the output connector 14C are transmitted to the bus bars 44A, 44B, and 44C.

Each of the bus bars 43A, 43B, 44A, 44B, and 44C is made of a long metal flat plate. For this reason, if resonance occurs in each of the bus bars 43A, 43B, 44A, 44B, and 44C, for example, the central portion in the longitudinal direction of the metal plate may vibrate more than the bolted connection portions at both ends. This vibration may cause the bolts in the bolted connection portions to loosen. To avoid such problems, in this embodiment, vibration-proof members 45 and 46 are provided as shown in Figures 6, 11, and 12.

The vibration-isolating member 45 suppresses vibration of the bus bars 43A and 43B in the first conductive part 43, and the vibration-isolating member 46 suppresses vibration of the bus bars 44A, 44B, and 44C in the second conductive part 44. Each of the vibration-isolating members 45 and 46 is made of an insulating material that cannot conduct electricity.

As shown in FIG. 11, two grooves 45i and 45j are formed in the vibration-proof member 45. The grooves 45i and 45j are each formed to have a groove width corresponding to the thickness of the bus bars 43A and 43B, and are formed to be deeper than the width (length in the short direction) of the bus bars 43A and 43B. The central portion in the longitudinal direction of the bus bar 43A is inserted into the groove 45i, and the central portion in the longitudinal direction of the bus bar 43B is inserted into the groove 45j. The vibration-proof member 45 is fixed to the case 14A with bolts.

Both ends of the bus bars 43A and 43B in the longitudinal direction are located outside the grooves 45i and 45j. In other words, both ends of the bus bars 43A and 43B are connected to the input connector 14B and the terminals 41A and 41B, respectively, and the central portions of the bus bars 43A and 43B in the longitudinal direction are clamped by the vibration-proof members 45 in the grooves 45i and 45j, respectively. This prevents the central portions of the bus bars 43A and 43B in the longitudinal direction from vibrating more than the both ends. As a result, the risk of the bolts fastened at both ends of the bus bars 43A and 43B becoming loose is greatly reduced.

In this embodiment, as shown in FIG. 12, the vibration-proof member 46 is provided with two rod-shaped bodies 46A and 46B that can clamp the bus bars 44A, 44B, and 44C together. The two rod-shaped bodies 46A and 46B clamp the central portions of the bus bars 44A, 44B, and 44C in the longitudinal direction in the central region. The two longitudinal ends of the two rod-shaped bodies 46A and 46B are connected by bolts. This prevents the central portions of the bus bars 44A, 44B, and 44C from vibrating more than the two ends. As a result, the risk of the bolts fastened to both ends of the bus bars 44A, 44B, and 44C becoming loose is greatly reduced.

[Another embodiment]
The present invention is not limited to the configurations exemplified in the above-described embodiments, and other representative embodiments of the present invention will be described below.

(1) In the above embodiment, the motor M drives and rotates both the traveling device and the actuation mechanism, but this is not limited to the embodiment. The motor M may be configured to drive and rotate either the traveling device or the actuation mechanism.

(2) In the above embodiment, the driving battery 4 and the inverter 14 are adjacent to each other vertically, but this is not limited to this embodiment. For example, the driving battery 4 and the inverter 14 may be adjacent to each other in the front-rear direction, or the driving battery 4 and the inverter 14 may be adjacent to each other in the left-right direction.

(3) In the above embodiment, the inverter 14 and the motor M are arranged adjacent to each other in the front-to-rear direction, but this is not limited to this embodiment. For example, the inverter 14 and the motor M may be arranged adjacent to each other in the top-to-bottom direction, or the inverter 14 and the motor M may be arranged adjacent to each other in the left-to-right direction. In addition, the inverter 14 and the motor M do not have to be adjacent to each other.

(4) In the above embodiment, the output connector 14C and the power receiving connector 22 are arranged so that they are offset left and right when viewed in the front-to-rear direction of the aircraft, but this is not limited to this embodiment. For example, the output connector 14C and the power receiving connector 22 may be arranged so that they are offset up and down when viewed in the front-to-rear direction of the aircraft. Also, the output connector 14C and the power receiving connector 22 may be configured so that they are not offset when viewed in the front-to-rear direction of the aircraft.

(5) In the above embodiment, the grass cutting device 19 is provided as the working device, but this is not limited to this embodiment. For example, the working device may be a cultivator, a seeding device, a planter, a fertilizer device, a leaf cutting device, a spraying device, a ridge forming device, a baler, a rotary rake, a tedder, etc.

(6) In the above embodiment, an electric tractor is shown as the electric work vehicle, but this is not limited to this embodiment. For example, the electric work vehicle may be an electric rice transplanter, an electric spreader, an electric sprayer, an electric combine harvester, an electric grass cutter, an electric wheel loader, an electric backhoe, etc.

The configurations disclosed in the above-mentioned embodiments (including other embodiments, the same applies below) can be applied in combination with configurations disclosed in other embodiments, so long as no contradiction occurs. Furthermore, the embodiments disclosed in this specification are merely examples, and the embodiments of the present invention are not limited thereto, and can be modified as appropriate within the scope of the purpose of the present invention.

The present invention can be applied to electric work vehicles equipped with an inverter that converts direct current from a battery into alternating current and supplies it to a motor.

2: Aircraft frame 2A: Front and rear frames (left and right aircraft frames)
2B: Horizontal frame 4: Running battery (battery)
10: Front wheels (running gear)
11: Rear wheels (running gear)
14: Inverter 14A: Case 14C: Output connector (first connector)
17: Mid PTO shaft (operating mechanism)
18: Rear PTO shaft (operating mechanism)
19: Grass cutting equipment (work equipment)
21: Power supply cable (conductive cable)
22: Power receiving connector (second connector)
42: Inverter module M: Motor

Claims (8)

An electric work vehicle that does not have an internal combustion engine and drives a traveling device and a working device with an electric motor,
The aircraft and
The traveling device has front wheels and rear wheels and causes the vehicle to travel;
an axle unit supporting the front wheels;
an actuation mechanism for transmitting power to the working device ;
The motor that rotates and drives at least one of the traveling device and the actuation mechanism;
a battery for supplying power to the motor;
an inverter that converts a direct current from the battery into an alternating current and supplies the alternating current to the motor;
a conductive cable electrically connected to each of the inverter and the motor for conducting the AC current to the motor;
the inverter includes an inverter module that converts the direct current into the alternating current, a case that houses the inverter module, and a first connector that protrudes outward beyond a surface portion of the case and is electrically connected to the conductive cable;
The battery and the inverter are disposed adjacent to each other,
The first connector is arranged in a state where it protrudes from the surface portion of the case opposite the side on which the battery is located, and is located on the front wheel side between the front wheels and the rear wheels, and is located between the axle unit and the battery in the vertical direction of the body of the electric work vehicle. The aircraft and
A traveling device that causes the machine body to travel;
an actuation mechanism for transmitting power to the working device;
a motor that rotates and drives at least one of the traveling device and the actuation mechanism;
a battery for supplying power to the motor;
an inverter that converts a direct current from the battery into an alternating current and supplies the alternating current to the motor;
a conductive cable electrically connected to each of the inverter and the motor for conducting the AC current to the motor;
the inverter includes an inverter module that converts the direct current into the alternating current, a case that houses the inverter module, and a first connector that protrudes outward beyond a surface portion of the case and is electrically connected to the conductive cable;
The battery and the inverter are disposed adjacent to each other,
the first connector is provided in the case so as to protrude from a surface portion on a side opposite to a side on which the battery is located,
The inverter and the motor are disposed adjacent to each other,
The first connector is provided in an area of the case opposite to the side on which the motor is located. The aircraft and
A traveling device that causes the machine body to travel;
an actuation mechanism for transmitting power to the working device;
a motor that rotates and drives at least one of the traveling device and the actuation mechanism;
a battery for supplying power to the motor;
an inverter that converts a direct current from the battery into an alternating current and supplies the alternating current to the motor;
a conductive cable electrically connected to each of the inverter and the motor for conducting the AC current to the motor;
the inverter includes an inverter module that converts the direct current into the alternating current, a case that houses the inverter module, and a first connector that protrudes outward beyond a surface portion of the case and is electrically connected to the conductive cable;
The battery and the inverter are disposed adjacent to each other,
the first connector is provided in the case so as to protrude from a surface portion on a side opposite to a side on which the battery is located,
the motor has a second connector that connects to the conductive cable;
An electric work vehicle in which the first connector and the second connector are arranged facing each other. the inverter and the motor are arranged side by side along a front-rear direction of the aircraft body,
The first connector and the second connector are arranged in a state where they are shifted from one another in a forward/rearward direction of the airframe,
The electric work vehicle according to claim 3 , wherein the first connector is provided in a state in which it is inclined toward the side where the second connector is located with respect to a fore-aft direction of the vehicle body. The aircraft and
A traveling device that causes the machine body to travel;
an actuation mechanism for transmitting power to the working device;
a motor that rotates and drives at least one of the traveling device and the actuation mechanism;
a battery for supplying power to the motor;
an inverter that converts a direct current from the battery into an alternating current and supplies the alternating current to the motor;
a conductive cable electrically connected to each of the inverter and the motor for conducting the AC current to the motor;
the inverter includes an inverter module that converts the direct current into the alternating current, a case that houses the inverter module, and a first connector that protrudes outward beyond a surface portion of the case and is electrically connected to the conductive cable;
The battery and the inverter are disposed adjacent to each other,
the first connector is provided in the case so as to protrude from a surface portion on a side opposite to a side on which the battery is located,
The airframe has left and right airframe frames extending in a front-rear direction,
the battery is mounted and supported on the left and right body frames in a state where it is located directly above the inverter,
the motor and the inverter are supported by the left and right body frames in a state where they are aligned along a front-rear direction of the body and are positioned between the left and right body frames,
The electrically- operated work vehicle, wherein the conductive cable is housed in the space between the left and right body frames. The electric work vehicle according to claim 5, wherein the inverter is detachably supported on the left and right vehicle frames. The airframe has a horizontal frame connecting the left and right airframe frames,
The electric work vehicle according to claim 5 or 6, wherein the conductive cable is located above the horizontal frame. The inverter is located in front of the motor,
8. The electric work vehicle according to claim 7, wherein the horizontal frame connects the left and right body frames at their lower parts, and extends longitudinally across an area where a front end of the inverter is located and an area where a front end of the motor is located in a plan view.

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