JP2023097970A - electric work vehicle - Google Patents

Abstract

To finely perform safety management of a vehicle body during charging.SOLUTION: An electric work vehicle is equipped with an electric motor M that can drive a vehicle body to travel, a battery 4 that supplies driving power to the electric motor M and can be charged by an external feeding device KD, a connecting portion 37 to which a feeding connector 36 on the feeding device side can be connected, and a control device 34 that controls the actuation of the electric motor M and controls a charging state by the feeding device KD. The control device 34 is configured to prohibit moving/traveling the vehicle body, during charging since starting charging while the feeding connector 36 is connected to the connecting portion 37 until charging to the battery 4 is completed.SELECTED DRAWING: Figure 4

Description

The present invention is configured to perform, for example, work on the ground or other work while the vehicle body is traveling, and includes an electric motor capable of driving the vehicle body and a battery that supplies driving power to the electric motor. It relates to an electric work vehicle.

In this type of electric working vehicle, for example, as described in Patent Document 1, when the power of the battery is consumed, charging is performed from an external power supply device connected via a connector. No special control was performed on the vehicle body side while the battery was being charged.

Japanese Patent Application Laid-Open No. 2021-957

Charging the battery may require a long time. As a result, while the battery is being charged, for example, it is conceivable that the driver forgets that the battery is being charged, and erroneously sits on the driving portion of the vehicle body and performs a driving operation. Also, it is conceivable that another person may perform the driving operation when the driver leaves the vehicle body. As a result, the vehicle body may move unexpectedly and the vehicle body and the power supply device may be damaged.

Therefore, there has been a demand for better safety management of the vehicle body during charging.

An electric working vehicle according to the present invention is characterized by an electric motor capable of driving a vehicle body, a battery that supplies driving power to the electric motor and is rechargeable by an external power supply device, and a A connection portion to which a power supply connector can be connected, and a control device that controls the operation of the electric motor and the charging state of the power supply device, wherein the control device controls the power supply connector when the power supply connector is connected to the connection. After the charging of the battery by the power supply device is started in the state connected to the unit, the vehicle body is prohibited from moving and running during the charging operation until the charging of the battery is completed. in the point.

According to the present invention, moving the vehicle body is prohibited during the charging operation from the start of charging the battery to the completion of charging. As a result, when a long time is required for charging, even if the driver accidentally sits on the driving part of the vehicle body and operates the vehicle, or if another person performs the driving operation, the vehicle body will not move. This avoids disadvantages such as damage to the vehicle body and the power supply device.

Therefore, it has become possible to perform good safety management of the vehicle body while the battery is being charged.

In the present invention, it is preferable that the control device is configured not to drive the electric motor during the charging operation.

According to this configuration, since the electric motor is not driven during the charging operation, the vehicle body does not move due to the power of the electric motor. When the vehicle body is equipped with a working device, the working device is not driven by the electric motor. Therefore, since the electric motor, which is the power source, cannot be driven, safety can be ensured.

In the present invention, the electric power from the battery is supplied to the electric motor via an inverter, and the control device stops the output to the inverter during the charging operation, thereby It is configured not to drive the motor.

According to this configuration, the operation of the electric motor can be reliably restrained by stopping the output to the inverter.

In the present invention, the power of the electric motor is transmitted to the vehicle body traveling device via the traveling clutch, and the control device receives a command to engage the traveling clutch during the charging operation. Also, it is preferable that the driving clutch is not switched to the engaged state.

According to this configuration, the traveling clutch is not engaged during the charging operation, so even if the electric motor is driven at this time, the vehicle body does not move and travel, ensuring safety. can be secured.

In this case, since the electric motor can be driven, for example, the working device can be driven while the movement of the vehicle body is stopped, and convenience in use can be improved.

In the present invention, the work device is attachable to and detachable from the vehicle body, the power of the electric motor is transmitted to the work device through the work clutch, and the control device is configured to operate during the charging operation. is preferably constructed so as not to switch to the engaged state of the work clutch even if a command to engage the work clutch is given.

According to this configuration, while the vehicle body is prohibited from moving and traveling during charging, the work clutch is prohibited from being switched to the engaged state, so that safety can be further improved.

It is a left view of a tractor. It is a left view which shows arrangement|positionings, such as an inverter. It is a figure which shows the flow of power transmission. It is a block diagram which shows the structure for charge. 4 is a flow chart of control operation; It is a figure which shows the flow of power transmission of another embodiment. It is a block diagram which shows the structure for charge of another embodiment.

A mode for carrying out the present invention will be described based on the drawings. In the following description, unless otherwise specified, the direction of arrow F in the drawings is "forward", the direction of arrow B is "rear", the direction of arrow L is "left", and the direction of arrow R is "left". Let's say "right". The direction of arrow U in the figure is defined as "up", and the direction of arrow D is defined as "down".

[Overall configuration of tractor]
A tractor as an example of an electric working vehicle according to the present invention will be described below. As shown in FIG. 1, the tractor includes left and right front wheels 10, left and right rear wheels 11, and a cover member 12 as a vehicle body traveling device.

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

The cover member 12 is arranged at the front part of the machine body. The operating section 3 is provided behind the cover member 12 . In other words, the cover member 12 is arranged in front of the driving section 3 .

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

The tractor has a battery 4 for running. The cover member 12 is configured to be swingable around an opening/closing axis Q extending in the lateral direction of the machine body. Thereby, the cover member 12 is configured to be openable and closable. The driving battery 4 is covered with the cover member 12 when the cover member 12 is in the closed state.

The tractor includes an inverter 14 and an electric motor M, as shown in FIG. The running battery 4 supplies power to the inverter 14 . Inverter 14 converts the DC power from running battery 4 into AC power and supplies it to electric motor M. As shown in FIG. The electric motor M is driven by AC power supplied from the inverter 14 .

As shown in FIGS. 2 and 3 , the tractor includes a hydrostatic continuously variable transmission 15 and a transmission 16 . As shown in FIG. 3, the hydrostatic continuously variable transmission 15 has a hydraulic pump 15a and a hydraulic motor 15b.

The hydraulic pump 15a is driven by rotational power from the electric motor M. As shown in FIG. Rotational power is output from the hydraulic motor 15b by driving the hydraulic pump 15a. The hydrostatic continuously variable transmission 15 is configured such that the rotational power is changed between the hydraulic pump 15a and the hydraulic motor 15b. The hydrostatic continuously variable transmission 15 is configured so that the gear ratio can be changed steplessly.

Rotational power output from the hydraulic motor 15 b is transmitted to the transmission 16 . The rotational power transmitted to the transmission 16 is changed in speed by a gear transmission mechanism of the transmission 16 and distributed to the left and right front wheels 10 and the left and right rear wheels 11 . As a result, the left and right front wheels 10 and the left and right rear wheels 11 are driven.

As shown in FIGS. 2 and 3, the tractor has a mid PTO shaft 17 and a rear PTO shaft 18. As shown in FIGS. Rotational power output from the electric motor M is distributed to the hydraulic pump 15a, the mid PTO shaft 17, and the rear PTO shaft 18. Thereby, the mid PTO shaft 17 and the rear PTO shaft 18 rotate.

If a working device is connected to the mid PTO shaft 17 or the rear PTO shaft 18, the rotational power of the mid PTO shaft 17 or the rear PTO shaft 18 drives the working device. For example, as shown in FIG. 2, a mower 19 is connected to the mid PTO shaft 17 in this embodiment. The rotary power of the mid PTO shaft 17 drives the lawn mower 19 .

[Configuration related to electric motor control]
As shown in FIG. 4 , the configuration related to control of the electric motor M includes an accelerator device 33 , a control device 34 that controls the operation of the electric motor M, and an inverter 14 . The accelerator device 33 is provided near the steering wheel 32 . Although not shown, the accelerator device 33 includes a swingable lever and a potentiometer operated by swinging the lever. The accelerator device 33 is connected with the control device 34 . The control device 34 is connected to the inverter 14 via a signal harness 35 . The control device 34 is configured to command the inverter 14 according to the command from the accelerator device 33 . The inverter 14 is configured to control the output of the electric motor M by adjusting the electric power supplied from the battery 4 for running to the electric motor M according to a command from the control device 34 .

[Configuration related to charging]
As shown in FIG. 4, the running battery 4 can be charged by an external power supply device KD. The tractor is provided with a charging connection portion 37 to which a power supply connector 36 on the side of the power supply device KD can be connected. The charging connection portion 37 is provided inside the cover member 12 and is exposed to the outside when the cover member 12 is opened by swinging. The control device 34 controls the operation of the electric motor M and also controls the charging state of the power supply device KD.

The charging connection 37 complies with commonly used standards. The running battery 4 is charged via the power supply line 39 while the power supply connector 36 on the power supply device KD side is connected to the charging connection portion 37 . The running battery 4 supplies electric power of high voltage (for example, several tens to several hundred volts) to the running electric motor M through the power supply line 39 .

The running battery 4 is configured using, for example, a lithium ion battery, and although not shown, is configured by stacking a large number of low-voltage small unit cells (cells), and the outside is covered with a storage case in a sealed state. It's packed away. Therefore, heat tends to accumulate inside the battery, and when the internal temperature rises, it is difficult for the temperature to drop. Therefore, the running battery 4 is provided with a temperature sensor 40 as temperature detecting means for detecting the internal temperature. Information detected by the temperature sensor 40 is input to the control device 34 .

The tractor is equipped with an electrical component battery 41 that supplies electric power to the control device 34 and other electrical components in addition to the running battery 4 . The electrical component battery 41 supplies low voltage (12 volts) power to drive the electrical components. The electrical component battery 41 is charged with electric power supplied from the running battery 4 via the DC/DC converter 42 .

The operating section 3 is provided with a switching operation section 44 as a start command means capable of switching the control device 34 between an operable state and a non-operating state. The switching operation unit 44 includes an insertion portion 46 as a mounted portion into which a portable operation key 45 can be inserted, and a push button type switch 47 that can be manually pushed. By pushing the switch 47 while the operation key 45 is inserted into the insertion portion 46, the control device 34 can be switched from the non-operating state to the operable state.

The operation panel 43 is provided with a meter panel 48 that displays, for example, the running state of the vehicle body, the working state, battery information (charge amount and temperature), and the like. The meter panel 48 is connected to the control device 34 and its operation is controlled by the control device 34 .

The control device 34, the inverter 14, the running battery 4, the DC/DC converter 42, the meter panel 48, the charging connector 37, etc. communicate data via a CAN (Controller Area Network) type signal harness 35. connected as possible. The control device 34 communicates with the charging connection portion 37 via the charging communication harness 49, and receives information as to whether or not the power supply connector 36 is connected to the charging connection portion 37, and Information such as the charging current required by the work vehicle is transmitted. Signals are also configured to be communicable between the charging connection portion 37 and the power supply device KD. Further, operation information of the switching operation unit 44 is input to the control device 34 .

[Control for charging]
When the control device 34 is switched to the operable state while the power supply connector 36 is connected to the charging connection portion 37, the control device 34 switches to the charging mode. In the charge mode, the power supply device KD is configured to charge the running battery 4 .

After the power supply device KD starts charging the running battery 4 with the power feeding connector 36 connected to the charging connection portion 37, the control device 34 waits until the charging of the running battery 4 is completed. During the charging operation, the vehicle body is prohibited from moving. Specifically, the control device 34 is configured not to drive the electric motor M during the charging operation.

After starting charging by the power supply device KD, the control device 34 is configured to continue charging by the power supply device KD even if the operation key 45 is switched to a state in which it is removed from the insertion portion 46 . . Further, if the charging by the power supply device KD is continued after the operation key 45 is removed from the insertion portion 46, the control device 34 automatically switches to the non-operating state when the charging is completed. configured to switch.

Specific charging control of the control device 34 will be described below with reference to the flowchart of FIG.

When charging the running battery 4 , the operator connects the power supply connector 36 of the power supply device KD to the charging connection portion 37 . Next, in the switching operation section 44 provided on the operation panel 43 of the operation section 3, the operation key 45 is inserted into the insertion section 46, and the switch 47 is pressed. When control device 34 recognizes this, it switches to the charging mode (steps #1, #2, #3).

When the mode is switched to the charging mode, the operation of the electric motor M is restrained by stopping the output of the inverter 14 (step #4). Next, necessary information is transmitted via the charging communication harness 49 so as to supply power to the power supply device KD, and charging of the running battery 4 by the power supply device KD is started (step #5).

The running battery 4 is charged to a preset charging state, and when it reaches the fully charged state, the charging is stopped (steps #6 and #7).

When charging is completed, it is determined whether or not the operation key 45 is inserted into the insertion portion 46 (step #8). At that time, if it is determined that the operation key 45 has been pulled out and not installed, it can be considered that the operation key 45 has been pulled out while the battery is being charged and the driver has taken it out, so the controller 34 is turned off. The power supply is forcibly cut off by switching to the non-operating state (step #09).

Therefore, if charging by the power supply device KD is continued after the operation key 45 is removed from the insertion portion 46, the control device 34 automatically switches to the non-operating state when the charging is completed. will be replaced.

If the operation key 45 is inserted when the charging is completed, the operator removes the power supply connector 36 of the power supply device KD to release the connection with the charging connection portion 37, and then the switch is turned on. When 47 is pushed, the charging mode is canceled (steps #08, #10, #11). At this time, by restarting the output of the inverter 14, the electric motor M is made operable, and the restrained state of the electric motor M is released (step #12). Therefore, while the running battery 4 is being charged, the electric motor M is not operated even if an operation for running the vehicle body is performed, and the vehicle body is prohibited from traveling.

[Another embodiment]
(1) In the above embodiment, the control device 34 does not drive the electric motor M during the charging operation.

As shown in FIG. 6, a traveling clutch 50 capable of connecting and disconnecting power is provided in the transmission path for transmitting the power of the electric motor M to the hydrostatic continuously variable transmission 15, and the power of the electric motor M is transferred to the mid PTO shaft. 17 is provided with a first working clutch 51 capable of connecting and disconnecting power, and a second working clutch capable of connecting and disconnecting power is provided in the transmission path transmitting the power of the electric motor M to the rear PTO shaft 18. 52 is provided. Then, as shown in FIG. 7, the controller 34 is configured to control the operation of each of the traveling clutch 50, the first work clutch 51, and the second work clutch 52. As shown in FIG.

When the hydrostatic continuously variable transmission 15 is used, a running stop state can be realized by the neutral position, so generally no clutch is provided. The device 34 normally sets the running clutch 50 to the engaged state, and during the charging operation, the control device 34 maintains the running clutch 50 in the disengaged state even if a command to engage the traveling clutch 50 is issued. By not switching to the clutch-engaged state, the movement of the vehicle body is prohibited.

At this time, if either the first work clutch 51 or the second work clutch 52 is maintained in the engaged state, the work device can be driven while the vehicle body is stopped. Also, during the charging operation, the first work clutch 51 and the second work clutch 52 may be maintained in the disengaged state.

Note that instead of such a configuration, either one of the first work clutch 51 and the second work clutch 52 may be provided, or neither of the work clutches may be provided.

(2) In the above embodiment, the operation keys 45 are configured to be insertable into the insertion portion 46. Alternatively, the control device 34 may be switched to the operable state when the switch 47 is operated while the operation key 45 is in proximity to the vehicle body.

(3) In the above-described embodiment, the controller 34 is configured to switch to the charging mode when the power supply connector 36 is connected to the charging connector 37 and switched to the operable state. Alternatively, the control device 34 may be switched to the operable state in advance and then switched to the charging mode when the power supply connector 36 is connected to the charging connection portion 37 .

The present invention can be applied not only to tractors but also to various electric working vehicles such as rice transplanters, combine harvesters, and construction machines.

4 Battery 36 Power Supply Connector 37 Connection Portion 50 Running Clutch 51 First Working Clutch 52 Second Working Clutch KD Power Supply Device M Electric Motor

Claims (5)

an electric motor capable of driving the vehicle body;
a battery that supplies drive power to the electric motor and is rechargeable by an external power supply device;
a connecting portion to which a power feeding connector on the power feeding device side can be connected;
a control device that controls the operation of the electric motor and controls the charging state of the power supply device;
After the power supply device starts charging the battery with the power supply connector connected to the connecting portion, the control device is configured to perform charging until the battery is completely charged. , an electric work vehicle configured to prohibit movement of the vehicle body. The electric working vehicle according to claim 1, wherein the control device is configured not to drive the electric motor during the charging operation. configured to supply power from the battery to the electric motor via an inverter;
3. The electric working vehicle according to claim 2, wherein the control device is configured not to drive the electric motor by stopping output to the inverter during the charging operation. configured to transmit the motive power of the electric motor to a vehicle body running device via a running clutch;
4. The control device according to any one of claims 1 to 3, wherein during the charging operation, the control device is configured not to switch to the engaged state of the traveling clutch even if a command to engage the traveling clutch is given. The electric work vehicle described in the paragraph. The work device is detachable from the vehicle body,
configured to transmit the power of the electric motor to the work device via a work clutch;
5. The control device according to any one of claims 1 to 4, wherein during the charging operation, even if a command to engage the work clutch is issued, the control device does not switch to the engaged state of the work clutch. The electric work vehicle described in the paragraph.

Images