Power supply device for electric work vehicles

Abstract

To provide, for an electric work vehicle, a power supply device which allows an external inverter to be removed when it is unnecessary, and prevents the connection of an inappropriate external inverter.SOLUTION: A power supply device for an electric work vehicle includes: a battery 2 for driving the electric work vehicle; a first connection part 21 for an internal inverter 7 which converts DC power from the battery 2 into AC power, and outputs the AC power to internal electric devices 15 and 32 installed in the electric work vehicle; a second connection part 22 for an external inverter 8 which converts DC power from the battery 2 into AC power, and outputs the AC power to an external electric device 9; and a battery control part 23 which is connected to the first connection part 21 and the second connection part 22, and controls the charging of and power supply from the battery 2. The battery control part 23 communicates with the external inverter 8 side via the second connection part 22, and performs authentication on whether or not power supply to the external inverter 8 is permitted.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a power supply device that is equipped on an electric work vehicle that is driven by power supplied from a battery. [Background technology]

[0002] Patent Document 1 discloses a tractor equipped with a working machine driven by an electric actuator. When the harness of the working machine is connected to a connection part of an external power supply harness extending from a battery, power is supplied from the battery of the tractor to the electric actuator. Only DC power from the battery is supplied to the connection part of the external power supply harness, and an inverter that converts DC power to AC power is required to drive an external electric device that requires AC power.

[0003] Patent Document 2 discloses a power supply device for an electric vehicle such as an electric car or a hybrid car, which converts DC power from a high-voltage drive battery into AC power and supplies the power to an external electric device via an accessory outlet installed inside the vehicle. This power supply device further includes an exterior outlet with a relay exposed outside the vehicle and a control means, and when a power cable for an external electric device is connected to the exterior outlet, the control means detects the connection and switches on the relay to supply AC power to the external electric device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-153962 A [Patent Document 2] JP 2014-030283 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the tractor of Patent Document 1, only DC power from the battery is supplied to the connection part of the external power harness, and an inverter that converts DC power to AC power is required to drive external electric devices that require AC power. In this case, if a high-output inverter or an inverter that does not meet the specifications is connected, the battery and the external power harness may be damaged. In addition, work vehicles such as tractors are often left outdoors, and in such situations, there is a problem of electricity theft through the connection part of the external power harness.

[0006] In the external power supply device disclosed in Patent Document 2, AC power is taken directly from an external outlet connected to the output section of the inverter, so that an external electric device that operates with AC power can be driven by connecting it to the external outlet. However, since the inverter for driving the external electric device is installed inside the vehicle, it is difficult to remove the inverter when the external electric device is not needed, or to select an appropriate inverter depending on the external electric device.

[0007] In view of the above-mentioned circumstances, an object of the present invention is to provide a power supply device for an electric work vehicle that allows the external inverter to be removed when not needed and prevents the connection of an inappropriate external inverter. [Means for solving the problem]

[0008] The power supply device for an electric work vehicle according to the present invention includes a battery for driving the electric work vehicle, and an internal inverter for converting DC power of the battery into AC power and outputting the AC power to an internal electric device installed in the electric work vehicle. and connecting the battery and the internal inverter. a first connection unit for converting the DC power of the battery into AC power and outputting the AC power to an external electric device; and connecting the battery and the external inverter. a second connection section for connecting the battery to the first connection section and the second connection section, and a battery control section that is connected to the first connection section and the second connection section and controls charging and power supply of the battery. a battery device incorporating the battery, the battery control unit, the first connection unit, the second connection unit, and the external inverter, the battery device being removable from the body of the electric work vehicle; The battery control unit communicates with the external inverter side via the second connection unit and performs authentication as to whether or not power supply to the external inverter is possible.

[0009] According to this configuration, in addition to a first connection section for an internal inverter that outputs to an internal electric device (such as a travel motor or a work motor), a second connection section for an external inverter is provided. When the external inverter is connected to the second connection section, the external inverter converts the DC power of the battery that is supplied to the second connection section into AC power and outputs it to the external electric device. At that time, the battery control section communicates with the external inverter side via the second connection section and authenticates whether or not power can be supplied to the external inverter, so that it is possible to prevent the DC power of the battery from being supplied to an inappropriate external inverter. Furthermore, with this configuration, the external inverter can be removed from the electric work vehicle when it is not needed. Alternatively, the external inverter can be permanently installed in any location of the electric work vehicle.

[0010] In one preferred embodiment of the present invention, the battery control unit supplies the DC power to the external inverter when the external inverter is connected to the second connection unit and a power supply permission is output from the control system of the electric work vehicle. In this configuration, even if the external inverter connected to the second connection unit is authenticated as an external inverter capable of supplying power, the external inverter is not supplied with power from the battery unless there is a power supply permission from the control system of the electric work vehicle. This makes it possible to stop the power supply from the battery under circumstances in which it is inappropriate to supply power to the external inverter, such as when the internal electric device is operating under high load or when there is no margin in the battery capacity. Note that the power supply permission from the control system may be configured to be output by the driver operating a specific operating tool.

[0011] In one preferred embodiment of the present invention, the battery, the battery control unit, the first connection unit, and the second connection unit are incorporated in a battery device that is mounted on the body of the electric work vehicle in a portable manner. In this configuration, the battery device including the battery can be removed from the body of the electric work vehicle and taken outside the vehicle. If the external inverter is attached to the battery device while connected to the second connection unit, the battery device together with the external inverter can be carried to a place where an external power source is required, particularly to a narrow place where the electric work vehicle cannot enter. This configuration is suitable for cases where a power source is required urgently, such as during a disaster. It is also suitable as a power source for outdoor camping.

[0012] In one preferred embodiment of the present invention, when a battery device including a battery is heavy, the battery device is provided with the external inverter and wheels for transportation in order to facilitate carrying the battery device. In this case, if the external inverter is also attached to the battery device, even a combination of a large and heavy battery and an external inverter can be smoothly moved to a place where an external power source is required. [Brief description of the drawings]

[0013] [Figure 1] 1 is an overall side view of an electric grass cutter, which is an example of an electric work vehicle. [Diagram 2] FIG. 2 is an overall plan view of the electric grass cutter. [Diagram 3] 1 is a perspective view of a battery device carried out of a vehicle body. FIG. [Figure 4] 11 is a perspective view of the electric grass cutter showing the vicinity of the battery storage unit after the battery device has been carried out. FIG. [Diagram 5] FIG. 2 is a perspective view showing a cable harness, a free connector, and a fixed connector. [Figure 6] FIG. 2 is a schematic diagram showing a power system and a control system of the electric grass cutter. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] In this specification, unless otherwise specified, "front" means forward in the longitudinal direction (driving direction) of the vehicle body, and "rear" means rearward in the longitudinal direction (driving direction) of the vehicle body. In addition, left-right or lateral means the transverse direction (vehicle width direction) of the vehicle body that is perpendicular to the longitudinal direction of the vehicle body. "Up" and "down" refer to the positional relationship in the vertical direction (perpendicular direction) of the vehicle body, and indicate the relationship in terms of height above ground.

[0015] Next, one embodiment of an electric working vehicle according to the present invention will be described. Here, the electric working vehicle is an electric grass cutter. As shown in Fig. 1 and Fig. 2, this electric grass cutter is equipped with a pair of left and right front wheels 11 supported on the front part of the vehicle body 1, a pair of left and right rear wheels 12 supported on the rear part of the vehicle body 1, and a mower unit 3 supported between the front wheels 11 and the rear wheels 12 under the vehicle body 1. A battery storage section 4 for storing a battery device 6 is provided between the left and right rear wheels 12. Furthermore, the vehicle body 1 is provided with a driver's seat 13, a rope frame 14, etc.

[0016] The vehicle body 1 includes a frame 10 consisting of right and left longitudinal beams extending in the front-rear direction and a cross beam connecting the longitudinal beams. The lower end of a ROPS frame 14 is connected to the frame 10.

[0017] The front wheels 11 are caster type wheels, and the rear wheels 12 are drive wheels. A pair of left and right travel motors 15 are disposed inside each rear wheel 12 as internal electric devices. The power of the travel motors 15 is transmitted to the rear wheels 12 via a reduction mechanism 16. Each rear wheel 12 is driven independently.

[0018] A gear shift lever 17 is disposed on each side of the driver's seat 13. When the right gear shift lever 17 is operated to the neutral position, the right traveling motor 15 is stopped. When the right gear shift lever 17 is operated to the forward side, the right traveling motor 15 rotates forward, and when the right gear shift lever 17 is operated to the reverse side, the right traveling motor 15 rotates reverse. Similarly, when the left gear shift lever 17 is operated to the neutral position, forward side, or reverse side, the left traveling motor 15 operates in the same manner as the right traveling motor 15 described above. In other words, by operating the right and left gear shift levers 17, the right and left rear wheels 12 are driven forward or reverse independently of each other, and the vehicle body 1 moves forward or reverse and turns right or left.

[0019] The mower unit 3 includes a mower deck 30 and a cutting blade 31 rotatably supported around a vertical axis inside the mower deck 30. The cutting blade 31 is driven to rotate by a cutting blade motor 32 serving as an internal electric device. The mower deck 30 is suspended from the frame 10 by a link mechanism 33 so as to be movable up and down.

[0020] The battery device 6 that supplies power to the travel motor 15 and the blade motor 32 is removably stored in the battery storage section 4. As shown in FIG. 3, the battery device 6 has a substantially cubic housing 60, and rollers 61 as transport wheels are provided on the bottom surface of the housing 60. The battery 2 is built into the housing 60. Battery guide rails 62 and battery guide rollers 63 are provided on the left and right sides of the housing 60. A power supply unit 20 for charging and power supply is provided on the central upper surface of the housing 60. An external inverter box 80 is disposed next to the power supply unit 20. An external inverter 8 is accommodated in the external inverter box 80. The external inverter 8 converts the DC power of the battery 2 into AC power and outputs it. An AC socket 82 of 100V or 200V that is connected to the external inverter 8 is provided on the outer surface of the external inverter box 80. A plug of an external electric device 9 such as a hand mower, a blower, or a chain saw is inserted into the AC socket 82.

[0021] As shown in FIG. 2, below the driver's seat 13 are disposed an internal inverter 7 that converts DC power from the battery 2 into AC power and outputs it to internal electric devices such as the traction motor 15 and the blade motor 32, and a control unit 5 that controls the internal inverter 7.

[0022] Although not shown in FIG. 5, the power supply unit 20 houses a battery control unit 23. As shown in FIG. 5, a first connection unit 21 and a second connection unit 22 to which a power supply line from the battery 2 is connected are provided on the side of the power supply unit 20. An internal harness 71, which is a power supply line to the internal inverter 7, is connected to the first connection unit 21. An external harness 81, which is a power supply line to the external inverter 8, is connected to the second connection unit 22. The battery control unit 23 has a function of controlling charging and power supply of the battery 2. The battery control unit 23 is connected to the first connection unit 21 and the second connection unit 22, and can control (ON / OFF) the power flowing through the switching units of the first connection unit 21 and the second connection unit 22. Furthermore, the battery control unit 23 is connected to the first connection unit 21 and the second connection unit 22 via a data communication line. The battery control unit 23 can exchange data with the internal inverter 7 via the data communication line of the first connection unit 21, and can exchange data with the external inverter 8 via the data communication line of the second connection unit 22. As will be described in detail later, the battery control unit 23 can authenticate whether or not power can be supplied to the external inverter 8 via the second connection unit 22.

[0023] The second connection part 22 can supply charging power to the battery 2 by connecting to a power supply line of a charging device (not shown). In other words, the second connection part 22 is also used as a charging port for the battery 2.

[0024] As shown in Fig. 4, the battery storage section 4 is formed between the rear ends of the left and right frames 10. A cross member 41 connecting the left and right frames 10 is configured to be used as a mounting base for the battery storage section 4. Furthermore, a vehicle body guide rail 42 and a vehicle body guide roller 43 are provided on the inner surfaces of the rear ends of the left and right frames 10. An internal harness 71 extends from the internal inverter 7 arranged below the driver's seat 13, and a first connector 71a is attached to the tip of the internal harness 71.

[0025] When the battery device 6 is loaded into the battery storage section 4, the battery guide rollers 63 are guided by the vehicle body guide rails 42, and the battery guide rails 62 come into contact with the vehicle body guide rollers 43. This allows the battery device 6 to move smoothly to a storage position in the battery storage section 4.

[0026] When the external inverter 8 is not needed, the external harness 81 together with the external inverter 8 can be stored in another location outside or inside the vehicle by disconnecting the second connection portion 22 from the connector 81a.

[0027] 6 shows a schematic diagram of the power system and control system of the electric grass cutter. The internal inverter 7 is made up of a travel motor inverter 7a and a mower motor inverter 7b. The travel motor inverter 7a supplies power to the pair of left and right travel motors 15 individually. The mower motor inverter 7b supplies power to the blade motor 32. The rotational power of the blade motor 32 is transmitted to the blade 31 via a belt transmission mechanism 34.

[0028] The control unit 5 has a calculation function for calculating the speed of the pair of left and right rear wheels 12 and a control function for the internal inverter 7. The control unit 5 calculates the rotation speeds of the left and right traveling motors 15 separately based on the amount of operation of the left and right speed change levers 17 that function as steering levers. Furthermore, the control unit 5 generates a control signal for supplying each traveling motor 15 with the power required to realize the rotation speed of each traveling motor 15 based on the calculation result, and supplies the control signal to the traveling motor inverter 7a. The traveling motor inverter 7a supplies the power based on the control signal to the traveling motor 15. This allows the electric lawnmower to travel straight ahead, turn left, and turn right.

[0029] The battery control unit 23 is connected to the first connection unit 21 and the second connection unit 22 via a data communication line, and in particular, can authenticate whether or not power can be supplied to the external inverter 8 via the second connection unit 22. In this authentication process, the battery control unit 23 acquires an identification code or specification data of the external inverter 8 from the external inverter 8 connected to the second connection unit 22, and compares it with an identification code or specification data of the external inverter 8 registered in advance. If the respective identification codes or specification data match in the comparison, power supply to the external inverter 8 connected to the second connection unit 22 is permitted. The above authentication method is an example, and authentication of whether or not power can be supplied may be performed using an IC tag or the like provided on the second connection unit 22 and the connector 81a of the external harness 81. In addition, various authentication methods can be adopted.

[0030] The battery control unit 23 is also connected to the control unit 5 so as to be able to exchange data with it. In this embodiment, an external power supply switch 18 that can be operated by the driver is connected to the control unit 5. The external power supply switch 18 is a switch that selects whether or not to supply external power, and the control unit 5 outputs power supply permission to the battery control unit 23 based on a signal from the external power supply switch 18. The battery control unit 23 does not supply power to the external inverter 8 via the second connection unit 22 unless this power supply permission is given. In other words, in this embodiment, when the external inverter 8 is connected to the second connection unit 22 and power supply permission is output from the control system of the electric work vehicle, the battery control unit 23 supplies DC power to the external inverter 8.

[0031] [Another embodiment] (1) In the electric work vehicle of the embodiment described above, the battery 2 is the only power source for the electrically powered equipment. However, a hybrid type power source including an internal combustion engine and the battery 2 may also be used. (2) In the above-described embodiment, the battery device 6 housing the battery 2 could be removed from the vehicle body 1 and used, but the battery device 6 may be fixed to the vehicle body 1, as in an electric passenger vehicle. (3) In the above-described embodiment, an electric lawnmower is given as an example of an electric work vehicle. However, the above-described power supply device can also be installed on other electric work machines, electric tractors, electric harvesters, electric construction machines, and the like.

[0032] In addition, the configurations disclosed in the above embodiments (including other embodiments, the same applies below) can be applied in combination with configurations disclosed in other embodiments, provided no contradiction arises. Furthermore, the embodiments disclosed in this specification are illustrative, and the embodiments of the present invention are not limited thereto, and can be appropriately modified within the scope that does not deviate from the purpose of the present invention. [Industrial Applicability]

[0033] The present invention is applicable to an electric work vehicle that is powered by a battery. [Explanation of symbols]

[0034] 1: Body 15: Driving motor (internal electric device) 18: External power supply switch 2: Battery 20: Power supply unit 21: First connection part 22: Second connection part 23: Battery control unit 3:Moore Unit 32: Blade motor (internal electric device) 4: Battery compartment 5: Control unit 6: Battery device 61: Roller (transport wheel) 7: Internal inverter 7a: Inverter for driving motor 7b: Mower motor inverter 71: Internal harness 71a: First connector 8: External inverter 80: External inverter box 81: External harness 81a : Connector 82: AC socket 9:External electric equipment

Claims

1. A power supply device for an electric work vehicle, a battery for driving the electric work vehicle; an internal inverter that converts DC power from the battery into AC power and outputs the AC power to an internal electric device installed in the electric work vehicle; a first connection portion for connecting the battery and the internal inverter; an external inverter that converts DC power from the battery into AC power and outputs the AC power to an external electrically powered device; a second connection portion for connecting the battery and the external inverter; a battery control unit connected to the first connection unit and the second connection unit and configured to control charging and power supply of the battery; a battery device incorporating the battery, the battery control unit, the first connection unit, the second connection unit, and the external inverter, the battery device being removable from a vehicle body of the electric work vehicle; Equipped with The battery control unit communicates with the external inverter side via the second connection unit, and authenticates whether or not power can be supplied to the external inverter.

2. A power supply device for an electric work vehicle as described in Claim 1, wherein the external inverter can be detached from the battery device by disconnecting it from the second connection part.

3. 3. The power supply device for an electric work vehicle according to claim 1 or 2, wherein the external inverter is connected to the second connection portion, and a power supply permission is output from a control system of the electric work vehicle, so that the battery control unit supplies the DC power to the external inverter.

4. 4. The power supply device for an electric work vehicle according to claim 1, wherein the battery device is provided with transportation wheels.

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