WO2025004898A1 - Work vehicle - Google Patents

Abstract

A work vehicle comprising a travel device (B), an engine (E), an electric motor (M), and a battery (T) that supplies electric power to the electric motor (M), wherein the engine (E) supplies motive power to the travel device (B) and/or charges the battery, the electric motor (M) supplies motive power to at least the travel device (B), and when traveling in a region in which the operation of the engine (E) is limited, the engine speed of the engine (E) is set to an idling speed or lower and travel is performed using the motive power from the electric motor (M).

Description

Work vehicle

The present invention relates to a work vehicle that is suitable for moving on uneven ground, such as slopes or uneven terrain.

A conventional work vehicle as described above has a structure in which a vehicle body is supported by multiple running wheels that can be extended or retracted by operating hydraulic cylinders and are driven by a hydraulic motor, and by changing the height of the running wheels, the vehicle body can be driven while maintaining its position even on slopes. Furthermore, this work vehicle is equipped with an engine as a drive source that drives a hydraulic pump, which is a hydraulic supply source (see, for example, Patent Document 1).

Japanese Patent Application Publication No. 2022-93124

In the above conventional configuration, an engine is installed as a drive source, so when driving the vehicle for work inside a building such as a vinyl greenhouse, for example, there is a disadvantage that the exhaust gases emitted can worsen the working environment, making the vehicle unsuitable for use indoors.

In light of environmental issues, it is conceivable to use an electric motor as the driving source instead of an engine, but if the vehicle is driven by an electric motor, the electric motor consumes a large amount of power, and so ensuring the battery's charge becomes an issue.

In particular, work vehicles suitable for moving on rough terrain such as those described above are often used in work areas that are not equipped with charging facilities, such as mountainous regions, and there is a risk that they will be unable to work if the battery does not have enough charge. On the other hand, if a large-capacity battery that allows for long-term work is installed, the vehicle body will become larger and the weight will be excessive. As a result, for example, in the case of work vehicles that are used to carry cargo, there are disadvantages such as an inability to ensure a sufficient load capacity.

To solve these problems, it is conceivable to equip the vehicle with an engine that can be used to charge the battery. However, if an engine is provided, when working indoors and the battery charge gets low, it will be necessary to generate electricity using the engine, which could worsen the working environment.

The object of the present invention is to provide a work vehicle that can perform long hours of work without increasing the weight of the vehicle body while avoiding deterioration of the indoor working environment.

The characteristic configuration of the work vehicle according to the present invention is that it is equipped with a traveling device, an engine, an electric motor, and a battery that supplies power to the electric motor, the engine at least either supplies power to the traveling device or charges the battery, the electric motor supplies power to at least the traveling device, and when traveling in an area where the operation of the engine is restricted, the engine speed is kept below the idling speed and the vehicle travels using power from the electric motor.

According to the present invention, when traveling in areas where engine operation is restricted, such as inside buildings, the traveling device is driven by the electric motor. In addition, since the battery that drives the electric motor can be charged by the engine, long-term operation is possible without the need for a large, high-capacity battery.

Furthermore, when driving in areas where engine operation is restricted, the engine speed is kept below idling speed, which reduces the amount of engine exhaust gas produced and makes it possible to work in an environment that does not deteriorate the work environment.

As a result, it has become possible to provide a work vehicle that can work for long periods of time without increasing the weight of the vehicle body, while avoiding deterioration of the indoor working environment.

In the present invention, it is preferable to set the engine speed to zero when traveling in an area where the engine's operation is restricted.

This configuration eliminates the generation of engine exhaust gas, ensuring that the indoor working environment does not deteriorate.

In the present invention, it is preferable that the area in which the operation of the engine is restricted is indoors or an area inside a restrictive boundary set a predetermined distance outside the indoors or the boundary between the indoors and outdoors, and that the area in which the operation of the engine is permitted is outdoors or an area outside the restrictive boundary.

With this configuration, the engine speed is limited to below idling speed not only indoors, i.e., inside the building, but also in the area inside the restricted boundary, for example, between a point located a certain distance outside the building entrance and the entrance. As a result, it is easy to effectively prevent engine exhaust gas from entering the building.

In the present invention, a switching mechanism is provided that can be switched between a first state that permits operation of the engine and a second state that restricts operation of the engine, and it is preferable that the switching mechanism switches to the first state when traveling outdoors and switches to the second state when traveling indoors.

With this configuration, the switching mechanism switches to the first state outdoors, allowing the engine to operate and charge the battery effectively. On the other hand, indoors, the switching mechanism switches to the second state and engine operation is restricted, allowing the working environment to be appropriately prevented from deteriorating.

In the present invention, it is preferable to provide a switching command means that can manually switch the switching mechanism between the first state and the second state.

With this configuration, the operator can switch the switching mechanism between the first state and the second state by operating the switching command means. As a result, for example, if the configuration automatically switches in response to various condition judgments, there is a risk of the engine operating unexpectedly due to judgment errors, but with this configuration, there is no such disadvantage, and it is possible to prevent the engine from operating unexpectedly against the operator's will.

In the present invention, it is preferable that a charging state detection means for detecting the charging state of the battery and a full charge notification means for notifying that the battery is in a fully charged state are provided, and when the fully charged state is notified, the switching mechanism is switched from the first state to the second state by operating the switching command means.

With this configuration, the full charge notification means notifies the operator that the battery is fully charged, allowing the operator to recognize this and, at the appropriate time when the full charge state is notified, the operator can operate the switching command means to switch to the second state.

In the present invention, a charging state detection means is provided for detecting the charging state of the battery, and the switching mechanism preferably switches from the first state to the second state when it determines, based on the detection information from the charging state detection means, that the battery has become fully charged as a result of charging caused by the operation of the engine.

With this configuration, when the charge state detection means detects that the battery is fully charged, the control device automatically switches to a charge restriction state. Therefore, when switching from a state in which the vehicle is traveling outdoors to a state in which the vehicle is traveling indoors, the operator does not need to perform any special switching operations, and can work indoors without hassle and without worsening the work environment.

In the present invention, it is preferable that a vehicle position determination means is provided that determines whether the vehicle is outdoors or indoors, and that the switching mechanism switches to the first state when the vehicle is outdoors and switches to the second state when the vehicle is indoors based on the determination result of the vehicle position determination means.

With this configuration, it is automatically determined whether the vehicle is outdoors or indoors, and the control device automatically switches to either the first or second state as appropriate based on the determination result, so there is no risk of the engine starting indoors due to an operator error, making it easy to use.

In the present invention, when a vehicle enters a building from the outdoors through a door, an open/closed state detection means is provided that detects whether the door is open or closed, and the control device preferably switches from the first state to the second state at a predetermined distance in front of the door when the open/closed state detection means detects that the door is open.

　With this configuration, if the door of the building is open and a work vehicle approaches the door with its engine running, there is a risk of exhaust gas entering the building. Therefore, with this configuration, the position of the work vehicle is determined, and if the door is open, the state is switched to the second state a specified distance in front of the door, thereby preventing exhaust gas from entering the building.

In the present invention, it is preferable that a posture discrimination means is provided for discriminating whether the vehicle is in an inclined posture, and the switching mechanism switches to the first state if the vehicle is in an inclined posture based on the discrimination result of the posture discrimination means, and switches to the second state if the vehicle is not in an inclined posture.

With this configuration, when working outdoors, the vehicle often assumes an inclined posture as it travels over rough ground. In contrast, when working inside a building, the ground is often flat. Therefore, with this configuration, the inclined posture state of the work vehicle can be automatically switched to an appropriate state, either a first state or a second state, based on the discrimination result.

In the present invention, it is preferable to provide a means for notifying the user that the battery is in a low-charge state due to use of the electric motor.

With this configuration, if the battery becomes low on charge while driving indoors, the operator will know this and can take immediate action, making it easy to use.

In the present invention, it is preferable that a support mechanism is provided that supports the multiple traveling devices on the vehicle body so that each can be raised and lowered, and that the engine is capable of driving the traveling devices and the support mechanism in place of the electric motor or in cooperation with the electric motor.

With this configuration, engine power can be used to supply hydraulic oil, improving the efficiency of engine power usage.

In the present invention, it is preferable that a support mechanism is provided that supports the plurality of traveling devices on the vehicle body so that each of the traveling devices can be raised and lowered separately, the plurality of traveling devices and the plurality of support mechanisms are configured to be hydraulically driven, a hydraulic oil supply device is provided that supplies hydraulic oil to the traveling devices and the support mechanisms, and the electric motor is configured to drive the hydraulic oil supply device.

Compared to the vehicle body, the vehicle's running gear and support mechanisms are more likely to be adversely affected by moisture and dust when they come into contact with mud or wet grass. However, with this configuration, these are hydraulically driven, so they are less susceptible to the effects of moisture and dust compared to, for example, electrically driven means, making it easier to perform stable work driving.

FIG. FIG. FIG. FIG. FIG. FIG. FIG. 2 is a diagram showing a configuration of a hydraulic supply source. FIG. 13 is a diagram showing the state of entering a building.

An embodiment of the work vehicle of the present invention will be described with reference to the drawings. In the following description, the direction of the arrow FW shown in the drawings will be referred to as "forward", the direction of the arrow BK as "rear", the direction of the arrow RH as "right", the direction of the arrow LH as "left", the direction of the arrow UP as "up", and the direction of the arrow DW as "down".

The work vehicle of this embodiment is equipped with a traveling device, an engine, an electric motor, and a battery that supplies power to the electric motor. The engine at least either supplies power to the traveling device or charges the battery, and the electric motor supplies power to at least the traveling device. When traveling in an area where engine operation is restricted, the engine speed is kept below idling speed and the vehicle travels using power from the electric motor.

The specific configuration is explained below.

As shown in Figures 1 to 3, the work vehicle is equipped with a vehicle body 1 that is substantially rectangular in plan view and that supports the entire vehicle, multiple hydraulically driven traveling devices B, and a hydraulically driven support mechanism A that supports the multiple traveling devices B on the vehicle body 1 so that they can be raised and lowered separately. The traveling devices B are equipped with traveling wheels 2 that support the vehicle body 1, and a hydraulic motor 4 that drives the traveling wheels 2. In addition, multiple auxiliary wheels 3 are provided in correspondence with each of the multiple traveling wheels 2.

The running wheels 2 are located at the front and rear on both the left and right sides of the vehicle body 1. In this embodiment, the work vehicle is equipped with four running wheels 2, located at the front left, front right, rear left, and rear right. Four support mechanisms A are provided at the front left, front right, rear left, and rear right, corresponding to the four running wheels 2. The support mechanism A is equipped with a bending link mechanism 5 as a vehicle body support part, and multiple hydraulic cylinders 6, 7 that can individually change the position of the bending link mechanism 5. The four running wheels 2 are supported via the bending link mechanism 5 so that they can be raised and lowered separately relative to the vehicle body 1.

The vehicle body 1 is generally rectangular in plan view, and the top surface of the vehicle body 1 is provided with a flat loading section 8 on which luggage can be loaded. The loading section 8 is generally rectangular in plan view, and extends from the right end to the left end of the vehicle body 1. The loading section 8 is configured so that luggage can be placed on it. Examples of luggage that can be placed on the loading section 8 include agricultural machinery, agricultural supplies such as fertilizer and chemicals, harvested crops and harvest baskets, and pallets on which these are placed.

The vehicle body 1 is equipped with a hydraulic supply source 9 that supplies hydraulic oil to the hydraulic equipment below the loading section 8, and a control device C that adjusts the supply of hydraulic oil from the hydraulic supply source 9 to control the operation of each hydraulic equipment (hydraulic cylinders 6, 7, hydraulic motor 4, etc.). The control device C constitutes a switching mechanism, which will be described later.

As shown in Figures 1 and 8, the hydraulic supply source 9 includes a hydraulic pump 10 as a hydraulic oil supply device that supplies hydraulic oil to the traveling device B and the support mechanism A, an electric motor M that drives the hydraulic pump 10, a battery T that supplies power to the electric motor M, a generator G that charges the battery T, and an engine E that drives the generator G. The engine E is an internal combustion engine that burns fuel to output rotational power, and emits exhaust gases during operation.

The electric motor M drives the hydraulic pump 10, and the hydraulic oil supplied from the hydraulic pump 10 is supplied to the traveling device B and the support mechanism A to drive them. Therefore, the electric motor M is configured to supply power to the traveling device B.

The control device C includes a hydraulic control mechanism 12 that adjusts the supply state of hydraulic oil from the hydraulic supply source 9, and an ECU (Electronic Control Unit) 13 that controls the operation of the hydraulic control mechanism 12. The ECU 13 includes a microcomputer and is capable of executing various controls according to a control program. The hydraulic control mechanism 12 includes multiple control valves (not shown) that individually supply and discharge hydraulic oil to and from each hydraulic device (hydraulic cylinders 6, 7, hydraulic motor 4, etc.) and adjust the flow rate.

[Support mechanism]
As shown in Figures 4 and 5, the bending link mechanism 5 includes a base end 14 supported by the vehicle body 1, a first link 15 having an upper end supported on a lower part of the base end 14 so as to be rotatable about a horizontal axis X1, and a second link 16 having one end supported on a lower end of the first link 15 so as to be rotatable about a horizontal axis X2 and having the running wheel 2 supported at the other end.

The support bracket 17 that supports the running wheel 2 is supported by a boss portion 18 provided at the swinging end of the second link 16 so that it can swing about the vertical axis Y. A hydraulic cylinder 20 (hereinafter referred to as a swing cylinder) for turning operation as a steering mechanism is provided between a bracket 19 on one end side of the second link 16 and an arm portion 17a provided on the support bracket 17.

　A plurality of hydraulic cylinders 6, 7 capable of individually changing the posture of each of the bending link mechanisms 5 are provided corresponding to each of the bending link mechanisms 5. That is, a first hydraulic cylinder 6 capable of changing the swing posture of the first link 15 relative to the vehicle body 1, and a second hydraulic cylinder 7 capable of changing the swing posture of the second link 16 relative to the first link 15 are provided.

When the first hydraulic cylinder 6 is extended or retracted with the second hydraulic cylinder 7 stopped, the first link 15, the second link 16, and the running wheel 2 each oscillate together around the horizontal axis X1 of the pivot connection point to the base end 14 while maintaining a constant relative posture. When the second hydraulic cylinder 7 is extended or retracted with the first hydraulic cylinder 6 stopped, the second link 16 and the running wheel 2 oscillate together around the horizontal axis X2 of the connection point between the first link 15 and the second link 16 while maintaining a constant posture of the first link 15.

The auxiliary wheels 3 are rotatably supported at the intermediate bent portions of each of the multiple bent link mechanisms 5. The auxiliary wheels 3 are configured with wheels having a smaller diameter than the running wheels 2. The support shaft that pivotally connects the first link 15 and the second link 16 is extended so as to protrude outward in the vehicle body width direction, and the auxiliary wheels 3 are rotatably supported at the extended protruding portion of the support shaft.

By operating the turning cylinder 20, the running wheel 2 can be rotated around the vertical axis Y relative to the bending link mechanism 5.

The position of each traveling wheel 2 relative to the vehicle body 1 can be changed by supplying and discharging hydraulic oil to the multiple first hydraulic cylinders 6, the multiple second hydraulic cylinders 7, and the swivel cylinder 20. In addition, the rotation speed of the hydraulic motor 4, i.e., the rotation speed of the traveling wheels 2, can be changed by adjusting the flow rate of the hydraulic oil corresponding to the hydraulic motor 4.

[Sensor]
This work vehicle is equipped with various sensors.

As shown in FIG. 6, each of the four second hydraulic cylinders 7 is provided with a head-side pressure sensor S1 and a cap-side pressure sensor S2. The head-side pressure sensor S1 detects the internal pressure of the oil chamber in the head-side chamber of the second hydraulic cylinder 7. The cap-side pressure sensor S2 detects the internal pressure of the oil chamber in the cap-side chamber of the second hydraulic cylinder 7.

Each of the four first hydraulic cylinders 6 and the four second hydraulic cylinders 7 is equipped with a plurality of stroke sensors S3 capable of detecting the amount of extension/retraction operation. The amount of extension/retraction operation of each hydraulic cylinder 6, 7 is a detection value corresponding to the swing position of the first link 15 and second link 16 that are the objects of operation.

The vehicle body 1 is equipped with a tilt sensor S4 that detects the tilt state of the vehicle body. The tilt sensor S4 is configured using an Inertial Measurement Unit (IMU), which is a well-known configuration. The IMU has a three-axis acceleration sensor and a gyro sensor, and can detect changes in the attitude of the vehicle body 1, specifically, tilt in the forward/backward and left/right directions.

A rotation sensor S5 is provided near the running wheels 2 to detect the rotation speed of the running wheels 2 driven by the hydraulic motor 4. Based on the rotation speed of the running wheels 2 detected by the rotation sensor S5, the supply of hydraulic oil to the hydraulic motor 4 is controlled so that the rotation speed of the running wheels 2 becomes a target value. A pressure sensor S6 is provided to detect the pressure of the hydraulic oil supplied to the hydraulic motor 4. Based on the pressure of the hydraulic oil detected by the pressure sensor S6, the supply (pressure) of hydraulic oil to the hydraulic motor 4 is controlled so that the drive torque of the running wheels 2 becomes a target value. Each of the four swivel cylinders 20 is provided with a stroke sensor S7 capable of detecting the amount of extension/retraction operation.

The vehicle body 1 is provided with a driving operation unit 21 behind the loading section 8. The driving operation unit 21 can be manually operated by the driver from outside the vehicle. The vehicle can be driven by the driver operating the driving operation unit 21.

The driving operation unit 21 is equipped with a so-called joystick-type control lever 29 that can be manually swung forward, backward, left, and right. By swung the control lever 29 forward, backward, left, and right from a neutral state (stopped state), the vehicle can be made to travel straight forward or backward, or turn in either the left or right direction. The driving operation unit 21 is also equipped with other operating tools.

[Vehicle control]
The ECU 13 includes a non-volatile memory (not shown) that stores programs corresponding to the functional units described below, and a CPU (not shown) that executes the programs. The functions of the functional units are realized by the CPU executing the programs. The ECU 13 includes, as the functional units, a posture control unit 100, a driving control unit 101, an engine control unit 102, and a charge state determination unit 103.

The attitude control unit 100 performs attitude control to control the attitude of the vehicle body to a desired state based on detection information from various sensors. There are two control modes for attitude control: a position control mode and a pressure control mode.

In the position control mode, the operation of the four first hydraulic cylinders 6 and the four second hydraulic cylinders 7 is controlled based on the detection information of the tilt sensor S4 and the detection information of the stroke sensor S3 so that the loading section 8 of the vehicle body 1 is in a horizontal position. Specifically, the hydraulic control valves corresponding to the four first hydraulic cylinders 6 and the four second hydraulic cylinders 7 are switched and controlled. As a result, even when traveling on a slope, the vehicle body 1 can maintain a substantially horizontal position, and can move without tipping over even if the loading section 8 is loaded with harvesting containers, equipment, etc.

In pressure control mode, the hydraulic control valve can be switched to control the operation of the four second hydraulic cylinders 30 so that the thrust of the second hydraulic cylinders 30, calculated based on the detection value of the head side pressure sensor S1 and the detection value of the cap side pressure sensor S2, becomes a target value that is set and stored in advance. By controlling in this way, the ground reaction force of the running wheels 2 is maintained at an appropriate value. As a result, the running wheels 2 rise and fall while following the unevenness of the ground, and each of the multiple running wheels 2 does not spin freely or have its rotation impeded, and the vehicle can run smoothly on uneven ground while maintaining an appropriate ground contact state and supporting the vehicle body 1.

The travel control unit 101 switches and controls the hydraulic control valves corresponding to the four turning cylinders 20 and the four hydraulic motors 4 based on the operating state of the steering lever 29. When the steering lever 29 is operated forward, the vehicle travels straight ahead, and when it is operated rearward, the vehicle travels straight ahead backward. Also, when the steering lever 29 is operated to the right, the vehicle turns to the right, and when it is operated to the left, the vehicle turns to the left.

The engine control unit 102, which will not be described in detail, is configured to be able to start, stop, and adjust the rotation speed of the engine E. If charging of the battery T is required, the engine E can be operated to drive the generator G and charge the battery T. The engine control unit 102 is configured to switch the charging state of the engine E, as will be described later.

(Switching the charging state by engine)
When the work vehicle according to the present invention travels in an area where the operation of the engine E is restricted, the rotation speed of the engine E is set to below the idling rotation speed and the work vehicle travels using power from the electric motor M. Specifically, when the work vehicle travels in an area where the operation of the engine E is restricted, the rotation speed of the engine E is set to zero. The area where the operation of the engine E is restricted is indoors, and the area where the operation of the engine E is permitted is outdoors. Indoors means, for example, inside a vinyl greenhouse, and outdoors means outside the vinyl greenhouse.

The vehicle is also provided with a switching mechanism that can be switched between a first state that permits the operation of engine E and a second state that restricts the operation of engine E, and the switching mechanism switches to the first state when traveling outdoors and switches to the second state when traveling indoors. In this embodiment, the switching mechanism is configured by a control device C.

In other words, the control device C can be switched between a first state that allows the operation of the engine E and a second state that restricts the operation of the engine E, and is switched to the first state when traveling outdoors and to the second state when traveling indoors.

Specifically, the control state of the engine E by the engine control unit 102 of the ECU 13 can be switched between a first state in which the engine E operates to charge the battery T, and a second state in which the engine E is stopped to restrict charging of the battery T. That is, in this embodiment, restricting the operation of the engine E means making the number of revolutions of the engine E zero. The state is switched to the first state outdoors, and to the second state indoors inside a vinyl greenhouse. As a result, when traveling outdoors, the engine E operates to charge the battery T, but when traveling inside a vinyl greenhouse, the air inside the room is not polluted by exhaust gases by restricting charging of the battery T through the operation of the engine E. The indoor state is not limited to the inside of a vinyl greenhouse, and may be the inside of another building such as a large warehouse.

This work vehicle is equipped with a switching command device 31 as a switching command means that can manually switch the control device C between a first state and a second state. In addition, a first display unit 33 is provided as a full charge notification means that notifies the user that the battery T is in a fully charged state, and when the full charge state is notified, the switching command device 31 is operated to switch the control device C from the first state to the second state.

That is, it is equipped with a charge detection sensor 32 as a charge state detection means for detecting the charge state of the battery T, a charge state determination unit 103 for determining that the battery T is fully charged based on the detection result of the charge detection sensor 32, and a first display unit 33 for notifying the operator by displaying information according to the determination result of the charge state determination unit 103.

The charge detection sensor 32 is a commonly used sensor with a well-known configuration, and its detection information is input to the control device C. The charge state determination unit 103 of the control device C determines whether the battery T is fully charged or not based on the detection information of the charge detection sensor 32 in accordance with a control program. The first display unit 33 is provided in the driving operation unit 21, and performs a display operation so that the operator operating the vehicle can visually confirm that the battery T is fully charged. At this time, in addition to the display operation by the first display unit 33, an audio notification such as a buzzer may also be performed.

Various display formats can be used for the first display unit 33. For example, it may be a lamp that lights up when the battery is not fully charged and goes out when the battery is not fully charged, or it may display an image. It may also be an analog display format, such as a bar graph that shows the charge level, or an analog display format in which segments of different light colors are arranged to show the charge level by changing the light emitted, and when the analog amount exceeds a reference value, it shows that the battery T is fully charged.

The switching command device 31 is provided in the driving operation unit 21 and is configured as a two-position switch. By manually switching the operating position, the control state of the engine E by the ECU 13 can be switched between a first state and a second state.

When the work vehicle continues to travel outdoors, the switching command device 31 is switched to the first state. This allows the engine E to be operated and the battery T to be charged. When the work vehicle switches from traveling outdoors to traveling indoors, the operator confirms on the first display unit 33 that the battery is fully charged and then switches the switching command device 31 to the second state.

The second display unit 34 is provided as a low charge notification means for notifying the user that the battery T has become low charge due to use of the electric motor M. As shown in FIG. 2, the second display unit 34 is provided to the side of the first display unit 33 in the driving operation unit 21. The second display unit 34 is used to notify the user that the battery T has become low charge in a manner that is recognizable by the operator. The various display forms mentioned for the full charge state can be used as the display form at this time. That is, when the charge state determination unit 103 determines that the battery T is in a low charge state based on the detection result of the charge detection sensor 32, the second display unit 34 notifies the user of this.

If the battery T runs out of charge while driving indoors, the vehicle will not be able to leave the building, and so the engine will need to generate power. Therefore, when reporting an insufficient charge, it is best to report this when the battery T still has enough charge to allow the vehicle to leave the building.

When working outdoors, the engine control unit 102 may perform automatic charging control. That is, when the battery T is fully charged as a result of charging performed by the operation of the engine E, the engine control unit 102 may automatically stop the operation of the engine E, and when the battery T is in an undercharged state, the engine control unit 102 may control the operation of the engine E so that the engine control unit 102 automatically starts the engine E and begins charging. This makes it possible to reduce unnecessary fuel consumption by the engine E.

[Another embodiment]
Other embodiments are listed below.

(1) In the above embodiment, the area in which the operation of engine E is restricted is indoors, and the area in which the operation of engine E is permitted is outdoors. Alternatively, a part of the indoor area may be set as the area in which the operation of engine E is restricted, and another part of the indoor area may be set as the area in which the operation of engine E is permitted. Also, a part of the outdoor area may be set as the area in which the operation of engine E is restricted, and another part of the outdoor area may be set as the area in which the operation of engine E is permitted.

(2) In addition to the configuration of the above embodiment, or instead of the switching configuration using the switching command device 31, the following configuration may be used.

A charging state detection means for detecting the charging state of the battery T may be provided, and the control device C may be configured to switch to the second state when the charging state detection means detects that the battery T is fully charged. In other words, when it is detected that the battery T is fully charged based on the detection information of the charging detection sensor 32 in the above embodiment as the charging state detection means, the control device C (specifically, the ECU) may be configured to automatically switch from the first state to the second state.

(3) In addition to the configuration of the above embodiment, or instead of the switching configuration using the switching command device 31, the following configuration may be used.

A vehicle position determination means may be provided to determine whether the vehicle is outdoors or indoors, and the control device C may be configured to switch to either a charging permitted state or a charging restricted state based on the determination result of the vehicle position determination means.

Furthermore, for example, as shown in FIG. 8, when a vehicle enters a building from the outdoors through a door 201 (corresponding to the boundary between indoors and outdoors) of the building 200, an open/closed state detection means (not shown) may be provided to detect whether the door 201 is open or closed, and the control device C may be configured to switch from a charging permitted state to a charging restricted state at a location a predetermined distance before the door 201 (corresponding to the restricted boundary) when the open/closed state detection means detects that the door 201 is open. In this case, even if the door 201 of the building 200 is open, the operation of the engine E can be stopped a predetermined distance (e.g., several meters) before the entrance to the building where the work vehicle is open, thereby effectively preventing exhaust gas from entering the building.

In other words, in this embodiment, the area in which the operation of engine E is restricted is the area inside the restricted boundary that is set indoors and a specified distance outside the boundary between indoors and outdoors, and the area in which the operation of engine E is permitted is the area outside the restricted boundary.

As a vehicle position determination means, for example, a satellite positioning module that receives signals (including GPS signals) from a satellite positioning system such as GNSS (Global Navigation Satellite System) to obtain the vehicle's position can be used. This makes it possible to determine whether the vehicle is inside a building (indoors) or outside (outdoors).

As an open/closed state detection means, for example, a configuration can be used that uses an imaging device such as a camera, LIDAR (Light Detection and Ranging), etc. to determine the presence or absence of an object (door).

(4) In the above embodiment, when traveling in an area where engine operation is restricted, the operation of engine E is restricted, i.e., the engine operation is stopped and the engine speed is set to zero. However, instead of this configuration, the speed of engine E may be adjusted to be equal to or lower than the idling speed. In this case, the amount of exhaust gas generated by the engine will not be reduced to zero, but it can be suppressed to as low an amount as possible.

(5) In addition to the configuration of the above embodiment, or instead of the switching configuration using the switching command device 31, the following configuration may be used.

The vehicle may be provided with a posture discrimination means for discriminating whether the vehicle is in an inclined posture, and the control device C may be configured to switch to the first state if the vehicle is in an inclined posture based on the discrimination result of the posture discrimination means, and to switch to the second state if the vehicle is not in an inclined posture. The posture discrimination means is configured using a tilt sensor S4 provided on the vehicle body and a posture control unit 100.

(6) The support mechanism A may be a mechanism having one link or three or more links, and may be equipped with an electric actuator as a device for changing the posture of the support mechanism A.

(7) The electric motor M may be configured to be switchable between a state in which it supplies power to the travel device B and the support mechanism A, and a state in which the engine E supplies power to the travel device B and the support mechanism A. In this case, when working indoors, the electric motor M switches to a state in which it supplies power to the travel device B and the support mechanism A. Furthermore, the electric motor M and the engine E may be configured to be switchable to a state in which they work together to supply power to the travel device B and the support mechanism A.

(8) Instead of the hydraulic cylinder 20 for the rotation operation, the configuration may be driven by a hydraulic motor, an electric motor, an engine, etc.

The present invention can be applied to work vehicles that are suitable for moving on slopes and uneven ground with bumps, for example.

10 Hydraulic pump (hydraulic oil supply device)
31 Switching command tool (switching command means)
32 Charging detection sensor (charging state detection means)
33 Full charge notification means 34 Low charge notification means A Support mechanism B Travel device C Control device (switching mechanism)
E Engine G Generator M Electric motor T Battery

Claims (13)

The vehicle includes a traveling device, an engine, an electric motor, and a battery that supplies power to the electric motor.
The engine performs at least one of supplying power to the traveling device and charging the battery,
The electric motor supplies power to at least the traveling device,
When the work vehicle is traveling in an area where the operation of the engine is restricted, the engine speed is kept below an idling speed and the work vehicle is travelling using power from the electric motor. The work vehicle according to claim 1, wherein the engine speed is set to zero when traveling in an area where the engine operation is restricted. The work vehicle according to claim 1 or 2, wherein the area in which the engine operation is restricted is indoors or an area inside a limiting boundary set a predetermined distance outside the indoors or the boundary between the indoors and outdoors, and the area in which the engine operation is permitted is outdoors or an area outside the limiting boundary. a switching mechanism that is switchable between a first state that permits operation of the engine and a second state that restricts operation of the engine,
4. The work vehicle according to claim 3, wherein the switching mechanism is switched to the first state when traveling outdoors and is switched to the second state when traveling indoors. The work vehicle according to claim 4, further comprising a switching command means capable of manually switching the switching mechanism between the first state and the second state. a charge state detection means for detecting a charge state of the battery;
a full charge notification means for notifying that the battery is in a fully charged state,
6. The work vehicle according to claim 5, wherein when the full-charged state is notified, the switching mechanism is switched from the first state to the second state by operating the switching command means. a charge state detection means for detecting a charge state of the battery is provided;
7. A work vehicle as claimed in any one of claims 4 to 6, wherein the switching mechanism switches from the first state to the second state when it determines, based on detection information from the charging state detection means, that the battery has become fully charged as a result of charging by operation of the engine. A vehicle position determination means is provided for determining whether the vehicle is outdoors or indoors;
8. A work vehicle as claimed in any one of claims 4 to 7, wherein the switching mechanism switches to the first state when the vehicle is outdoors and switches to the second state when the vehicle is indoors based on the determination result of the vehicle position determination means. an open/closed state detection means for detecting whether the door is open or closed when a vehicle enters a building from the outdoors through the door,
The work vehicle according to any one of claims 4 to 8, wherein the switching mechanism switches from the first state to the second state a predetermined distance in front of the door portion when the open/closed state detection means detects that the door portion is in an open state. The vehicle is provided with a posture determination means for determining whether the vehicle is in a tilted posture state,
10. A work vehicle as claimed in any one of claims 4 to 9, wherein the switching mechanism switches to the first state if the vehicle is in an inclined position based on the determination result of the position determination means, and switches to the second state if the vehicle is not in an inclined position. The work vehicle according to any one of claims 1 to 10, which is provided with a charge shortage notification means for notifying the user that the battery has become insufficiently charged due to use of the electric motor. a support mechanism for supporting the plurality of traveling devices on a vehicle body so that each traveling device can be raised and lowered;
12. The work vehicle according to claim 1, wherein the engine is capable of driving the traveling device and the support mechanism in place of the electric motor or in cooperation with the electric motor. a support mechanism for supporting the plurality of traveling devices on a vehicle body so that each traveling device can be raised and lowered;
The plurality of traveling devices and the plurality of support mechanisms are configured to be hydraulically driven,
A hydraulic oil supply device is provided for supplying hydraulic oil toward the traveling device and the support mechanism,
The work vehicle according to any one of claims 1 to 12, wherein the electric motor is configured to drive the hydraulic oil supply device.

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