Service vehicle

Abstract

To provide a service vehicle that can perform work for a long time without increasing weight of a vehicle body more, while avoiding deterioration in indoor working environment.SOLUTION: The service vehicle is equipped with a running device B, an engine E, an electric motor M, and a battery T that supplies electric power to the electric motor M. The engine E performs at least either of supplying power to the running device B and charging the battery. The electric motor M supplies power to at least the running device B. When running in an area where the engine E is restricted from operating, the service vehicle runs by power from the electric motor M, while keeping rotation speed of the engine E to be equal to idling rotation speed or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a work vehicle suitable for moving on, for example, slopes or uneven ground with bumps. [Background technology]

[0002] Conventionally, the above-mentioned work vehicle has been configured such that a plurality of traveling wheels driven by a hydraulic motor are supported on the vehicle body so as to be extendable and retractable by operating a hydraulic cylinder, and the height of the traveling wheels can be changed to enable traveling while maintaining the attitude of the vehicle body even on slopes, etc. In addition, this work vehicle is equipped with an engine as a drive source that drives a hydraulic pump, which is a hydraulic supply source (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-93124 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned conventional configuration, an engine is mounted as a driving source. Therefore, when the vehicle is driven for work inside a building such as a vinyl greenhouse, the exhaust gas emitted from the vehicle can worsen the working environment, making the vehicle unsuitable for use indoors.

[0005] In light of environmental issues, it may be considered to use an electric motor instead of an engine as the driving source. However, 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.

[0006] In particular, in the case of a work vehicle suitable for moving on rough ground as described above, the vehicle is often used in work areas that are not equipped with charging facilities, such as mountainous areas, and there is a risk that the vehicle will be unable to work if the battery is insufficiently charged. On the other hand, if a large-capacity battery that allows long-term work is installed, the vehicle body becomes large and the weight becomes excessive. As a result, for example, in the case of a work vehicle that is used to carry cargo, there is a disadvantage in that a sufficient load capacity cannot be secured.

[0007] One possible solution to this problem is to install an engine so that the battery can be charged by the engine. However, when an engine is installed, if the battery charge level becomes low during indoor work, it becomes necessary to generate electricity using the engine, which may worsen the working environment.

[0008] An object of the present invention is to provide a work vehicle capable of performing work for long periods of time without increasing the weight of the vehicle body, while avoiding deterioration of the indoor working environment. [Means for solving the problem]

[0009] The characteristic configuration of the work vehicle of 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 operation of the engine is restricted, the engine speed is kept below idling speed and the vehicle travels using power from the electric motor.

[0010] According to the present invention, when traveling in an area where engine operation is restricted, such as inside a building, the traveling device is driven by the electric motor. Also, since the battery that drives the electric motor can be charged by the engine, long-term operation is possible without a large, high-capacity battery.

[0011] Furthermore, when traveling in areas where engine operation is restricted, the engine speed is kept below idling speed, reducing the amount of engine exhaust gas produced and making it possible to work in an environment that does not deteriorate the working environment.

[0012] It is therefore possible to provide a work vehicle that is capable of working for long periods of time without increasing the weight of the vehicle body, while avoiding deterioration of the indoor working environment.

[0013] In the present invention, when the vehicle is traveling in an area where the operation of the engine is restricted, it is preferable to set the engine speed to zero.

[0014] According to this configuration, it is possible to eliminate the generation of exhaust gas from the engine, so that it is possible to reliably avoid deterioration of the indoor working environment.

[0015] In the present invention, it is preferable that the area in which operation of the engine is restricted is indoors or an area inside a restrictive boundary set a predetermined distance outside the indoors and the boundary between the indoors and outdoors, and that the area in which operation of the engine is permitted is outdoors or an area outside the restrictive boundary.

[0016] According to this configuration, the engine speed is limited to the idling speed or less not only inside the building, but also in the area inside the limiting boundary, for example, between a point located a certain distance outside the building entrance and the entrance, which makes it easy to effectively prevent engine exhaust gas from entering the building.

[0017] In the present invention, a switching mechanism is provided that is switchable 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.

[0018] According to this configuration, since the switching mechanism is switched to the first state outdoors, the battery can be charged smoothly by operating the engine, whereas, since the switching mechanism is switched to the second state indoors and the operation of the engine is restricted, deterioration of the working environment can be appropriately avoided.

[0019] In the present invention, it is preferable that a switching command means is provided that is manually operable to switch the switching mechanism between the first state and the second state.

[0020] According to this configuration, an 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, in a configuration in which switching is performed automatically in response to various condition determinations, there is a risk of the engine operating unexpectedly due to a determination error, but with this configuration, such a disadvantage does not occur and it is possible to prevent the engine from operating unexpectedly against the operator's will.

[0021] 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 fully charged are provided, and when the full charge state is notified, the switching mechanism is switched from the first state to the second state by operating the switching command means.

[0022] According to this configuration, the full charge notification means notifies the operator that the battery is fully charged, so that the operator can recognize this and can operate the switching command means to switch to the second state at the appropriate timing when the full charge state is notified.

[0023] In the present invention, it is preferable that a charging state detection means is provided for detecting the charging state of the battery, and 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 due to operation of the engine.

[0024] According to 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 of driving outdoors to a state of driving indoors, the operator does not have to perform any special switching operation, and can work indoors without hassle and without worsening the work environment.

[0025] In the present invention, it is preferable that a vehicle position discrimination means is provided which discriminates whether the vehicle is outdoors or indoors, and 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 discrimination result of the vehicle position discrimination means.

[0026] According to this configuration, it is automatically determined whether the vehicle is outdoors or indoors, and the control device automatically switches to the appropriate state, either the first state or the second state, depending on the determination result. This eliminates the risk of the engine being started indoors due to an operator error, making the system easy to use.

[0027] In the present invention, an open / closed state detection means is provided for detecting whether the door section is open or closed when a vehicle enters a building from outdoors through the door section, and it is preferable that when the open / closed state detection means detects that the door section is open, the control device switches from the first state to the second state a predetermined distance before the door section.

[0028] According to this configuration, if the door of the building is open and the work vehicle approaches the door with the engine running, there is a risk of exhaust gas entering the building. Therefore, in this configuration, by utilizing the fact that the position of the work vehicle is determined, if the door is open, the state is switched to the second state a predetermined distance in front of the door, thereby preventing exhaust gas from entering the building.

[0029] 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.

[0030] According to this configuration, when working outdoors, the vehicle often assumes an inclined posture because it travels over rough ground. In contrast, when working inside a building, the ground is often flat. Therefore, with this configuration, the inclined posture of the work vehicle can be automatically switched to an appropriate state, either state 1 or state 2, based on the discrimination result.

[0031] In the present invention, it is preferable to provide a low-charge notification means for notifying that the battery has become low-charged as a result of use of the electric motor.

[0032] According to this configuration, when the battery is running low on charge while the vehicle is being driven indoors, the operator can know this and immediately take appropriate action, making the vehicle easy to use.

[0033] 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 of the traveling devices can be raised and lowered separately, 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.

[0034] According to this configuration, the power of the engine can be utilized to supply the hydraulic oil, and the efficiency of utilizing the engine power can be improved.

[0035] In the present invention, it is preferable that a support mechanism is provided for supporting the multiple traveling devices on the vehicle body so that each of the multiple traveling devices can be raised and lowered separately, the multiple traveling devices and the multiple support mechanisms are configured to be hydraulically driven, a hydraulic oil supply device is provided for supplying hydraulic oil to the traveling devices and the support mechanisms, and the electric motor is configured to drive the hydraulic oil supply device.

[0036] Compared to the vehicle body, the running gear and support mechanism of the vehicle are more likely to be adversely affected by moisture, dust, etc., when they come into contact with mud, wet grass, etc. However, according to the present configuration, since they are hydraulically driven, they are less susceptible to the effects of moisture, dust, etc., and are easier to drive for work in a stable manner, compared to, for example, electrically driven means. [Brief description of the drawings]

[0037] [Figure 1] FIG. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. [Figure 7] FIG. 2 is a diagram showing a configuration of a hydraulic supply source. [Figure 8] FIG. 13 is a diagram showing the state of entering a building. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] 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 is defined as "forward", the direction of the arrow BK is defined as "rear", the direction of the arrow RH is defined as "right", the direction of the arrow LH is defined as "left", the direction of the arrow UP is defined as "up", and the direction of the arrow DW is defined as "down".

[0039] 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, and 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, and 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.

[0040] A specific configuration will be described below.

[0041] As shown in Figures 1 to 3, the work vehicle is equipped with a vehicle body 1 having a substantially rectangular shape in a plan view 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 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 corresponding to the multiple traveling wheels 2, respectively.

[0042] The traveling wheels 2 are located at the front and rear of both the left and right sides of the vehicle body 1. In this embodiment, the work vehicle is equipped with four traveling wheels 2, located at the left front, right front, left rear, and right rear. Four support mechanisms A are provided at the left front, right front, left rear, and right rear, corresponding to the four traveling wheels 2, respectively. The support mechanism A is equipped with a bending link mechanism 5 as a vehicle body support part, and a plurality of hydraulic cylinders 6, 7 that can individually change the attitude of the bending link mechanism 5. The four traveling 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.

[0043] The vehicle body 1 is generally rectangular in plan view, and a flat loading section 8 capable of loading luggage is provided on the upper surface of the vehicle body 1. 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 thereon. Examples of luggage that can be placed on the loading section 8 include agricultural machinery, agricultural materials such as fertilizer and chemicals, harvested crops and harvesting baskets, and pallets on which these are placed.

[0044] The vehicle body 1 is provided, below the loading section 8, with a hydraulic supply source 9 that supplies hydraulic oil to the hydraulic equipment, and a control device C that controls the operation of each hydraulic equipment (hydraulic cylinders 6, 7, hydraulic motor 4, etc.) by adjusting the supply state of hydraulic oil from the hydraulic supply source 9. The control device C constitutes a switching mechanism, which will be described later.

[0045] 1 and 8, the hydraulic supply source 9 includes a hydraulic pump 10 serving 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, 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.

[0046] The electric motor M drives a hydraulic pump 10, and hydraulic oil supplied from the hydraulic pump 10 is supplied to the traveling device B and the support mechanism A to drive them. Thus, the electric motor M is configured to supply power to the traveling device B.

[0047] 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 a plurality of 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.), adjust the flow rate, etc.

[0048] [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.

[0049] A support bracket 17 that supports the traveling wheel 2 is supported by a boss portion 18 provided at the swing side end of the second link 16 so as to be swingable around the vertical axis Y. A hydraulic cylinder 20 (hereinafter referred to as a swing cylinder) for swing 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.

[0050] 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 the plurality of 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.

[0051] 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 traveling wheel 2 swing together around the horizontal axis X1 of the pivot connection point with respect 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 traveling wheel 2 swing 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.

[0052] An auxiliary wheel 3 is rotatably supported at an intermediate bent portion of each of the multiple bent link mechanisms 5. The auxiliary wheel 3 is configured as a wheel having a smaller diameter than the traveling wheel 2. A 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 wheel 3 is rotatably supported at the extended protruding portion of the support shaft.

[0053] By operating the turning cylinder 20, the traveling wheel 2 can be turned around the vertical axis Y relative to the articulating link mechanism 5, thereby enabling the vehicle to be turned.

[0054] The position of each traveling wheel 2 with respect 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 turning 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.

[0055] [Sensor] This work vehicle is equipped with various sensors.

[0056] 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.

[0057] A plurality of stroke sensors S3 capable of detecting the amount of extension / retraction operation are provided for each of the four first hydraulic cylinders 6 and the four second hydraulic cylinders 7. 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 the second link 16 that are the objects of operation.

[0058] The vehicle body 1 is provided 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) that is a well-known configuration. The IMU has a three-axis acceleration sensor and a gyro sensor, and can detect the change in the attitude of the vehicle body 1, specifically, the tilt in the front-rear and left-right directions.

[0059] A rotation sensor S5 is provided near the traveling wheels 2 to detect the rotation speed of the traveling wheels 2 driven by the hydraulic motor 4. Based on the rotation speed of the traveling 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 traveling 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 traveling wheels 2 becomes a target value. A stroke sensor S7 capable of detecting the extension / retraction operation amount is provided for each of the four swing cylinders 20.

[0060] A driving operation unit 21 is provided behind the loading section 8 of the vehicle body 1. 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.

[0061] The driving operation unit 21 is provided with a so-called joystick type steering lever 29 that can be manually swung forward, backward, left and right. By swinging the steering 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 provided with other operating tools.

[0062] [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 programs are executed by the CPU to realize the functions of the functional units. The ECU 13 includes a posture control unit 100, a driving control unit 101, an engine control unit 102, and a charge state determination unit 103 as the functional units.

[0063] The attitude control unit 100 executes attitude control for controlling the attitude of the vehicle body to a desired state based on detection information from various sensors. The attitude control has a position control mode and a pressure control mode.

[0064] 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 can maintain a substantially horizontal position, and can move without falling over even if the loading section is loaded with harvesting containers, equipment, etc.

[0065] In the 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 traveling wheels 2 is maintained at an appropriate value. As a result, the traveling wheels 2 move up and down while following the unevenness of the ground, and each of the multiple traveling 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.

[0066] The travel control unit 101 switches and controls hydraulic control valves corresponding to the four swing 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. 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.

[0067] Although not described in detail, the engine control unit 102 is configured to be able to perform start processing, stop processing, and rotation speed adjustment processing of the engine E. If charging of the battery T is required, the engine E is operated to drive the generator G, thereby charging the battery T. The engine control unit 102 is configured to switch the charging state of the engine E, as will be described later.

[0068] (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.

[0069] The vehicle is provided with a switching mechanism that can be switched between a first state that permits the operation of the engine E and a second state that restricts the operation of the 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 constituted by the control device C.

[0070] That is, the control device C is switchable 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 switches to the first state when driving outdoors and switches to the second state when driving indoors.

[0071] 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 the 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, such as inside a vinyl house. As a result, when traveling outdoors, the engine E operates to charge the battery T, but when traveling inside a vinyl house, the charging of the battery T by the engine E is restricted so that the air inside the room is not polluted by exhaust gas. The indoors is not limited to the inside of a vinyl house, and may be the inside of another building such as a large warehouse.

[0072] This work vehicle is provided with a switching command device 31 as switching command means capable of manually switching the control device C between a first state and a second state. Also, a first display unit 33 is provided as full charge notification means for notifying that the battery T is in a fully charged state, and when the full charge state is notified, the control device C is switched from the first state to the second state by operating the switching command device 31.

[0073] That is, it is equipped with a charging detection sensor 32 as a charging state detection means for detecting the charging state of battery T, a charging state determination unit 103 for determining that battery T has reached a fully charged state based on the detection result of the charging detection sensor 32, and a first display unit 33 for notifying an operator by display information according to the determination result of the charging state determination unit 103.

[0074] The charge detection sensor 32 is a commonly used sensor having 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, a sound such as a buzzer may also be used to notify the operator.

[0075] 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 be displayed by an image. It may also be an analog display format, such as a bar graph that shows the charge amount, or an analog display format in which different light-emitting segments are arranged to show the charge amount by changing the light emitted, and when the analog amount exceeds a reference value, it shows that the battery T is fully charged.

[0076] 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 operation position, the control state of the engine E by the ECU 13 can be switched between a first state and a second state.

[0077] When the work vehicle continues to travel outdoors, the switching command device 31 is switched to the first state side. This allows the engine E to operate and charge the battery T. When the work vehicle switches from a state traveling outdoors to a state traveling indoors, the operator confirms on the first display unit 33 that the battery is fully charged and switches the switching command device 31 to the second state.

[0078] The vehicle is provided with a second display unit 34 as a charge shortage notification means for notifying that the battery T has become in a charge shortage state due to the use of the electric motor M. As shown in FIG. 2, the second display unit 34 is provided on the side of the first display unit 33 in the driving operation unit 21. The second display unit is used to display and notify the operator that the battery T has become in a charge shortage state in a manner that the operator can recognize. As the display form at this time, the various forms mentioned for the full charge state can be adopted. That is, when the charge state determination unit 103 determines that the battery T is in a charge shortage state based on the detection result of the charge detection sensor 32, the second display unit 34 notifies the operator of the state.

[0079] If the battery T runs out of charge while traveling 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 state, it is advisable to report this when the battery T has a sufficient charge to allow the vehicle to leave the building.

[0080] 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 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 insufficient charge 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 to start charging. This makes it possible to suppress unnecessary fuel consumption by the engine E.

[0081] [Another embodiment] Other embodiments are listed below.

[0082] (1) In the above embodiment, the area where the operation of engine E is restricted is indoors, and the area where the operation of engine E is permitted is outdoors, but instead, a part of the indoor area may be set as the area where the operation of engine E is restricted, and another part of the indoor area may be set as the area where the operation of engine E is permitted. Also, a part of the outdoor area may be set as the area where the operation of engine E is restricted, and another part of the outdoor area may be set as the area where the operation of engine E is permitted.

[0083] (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.

[0084] 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 has reached a fully charged state. That is, when it is detected that the battery T has reached a fully charged state based on detection information from 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.

[0085] (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.

[0086] 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.

[0087] Furthermore, for example, as shown in Fig. 8, when a vehicle enters a building from outdoors through a door 201 (corresponding to a 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 the charging permitted state to the charging restricted state at a location (corresponding to a restricted boundary) a predetermined distance before the door 201 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.

[0088] That is, in this embodiment, the area in which the operation of engine E is restricted is the area inside the restriction boundary set indoors and a predetermined 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 restriction boundary.

[0089] The vehicle position determination means may be, for example, a satellite positioning module that receives signals (including GPS signals) from a satellite positioning system such as the Global Navigation Satellite System (GNSS) to obtain the vehicle's position. This makes it possible to determine whether the vehicle is inside (indoors) or outside (outdoors) of a building.

[0090] The open / closed state detection means may be configured to determine the presence or absence of an object (door) using, for example, an imaging device such as a camera, LiDAR (Light Detection And Ranging), or the like.

[0091] (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, but 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 is not reduced to zero, but it is possible to suppress the amount to be as small as possible.

[0092] (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.

[0093] The vehicle may be provided with a posture discrimination means for discriminating whether the vehicle is in a tilted posture or not, and the control device C may be configured to switch to the first state if the vehicle is in a tilted posture based on the discrimination result of the posture discrimination means, and to switch to the second state if the vehicle is not in a tilted posture. The posture discrimination means is configured by utilizing a tilt sensor S4 provided on the vehicle body and a posture control unit 100.

[0094] (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.

[0095] (7) The electric motor M may be configured to be switchable between a state in which it supplies power to the traveling device B and the support mechanism A, and a state in which the engine E supplies power to the traveling device B and the support mechanism A. In this case, when working indoors, the electric motor M is switched to a state in which it supplies power to the traveling 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 cooperate to supply power to the traveling device B and the support mechanism A.

[0096] (8) Instead of the hydraulic cylinder 20 for the turning operation, a configuration may be adopted in which a hydraulic motor, an electric motor, an engine, or the like is used for driving the turning operation. [Industrial Applicability]

[0097] The present invention can be applied to a work vehicle that is suitable for moving on, for example, slopes or uneven ground with bumps. [Explanation of symbols]

[0098] 10 Hydraulic pump (hydraulic oil supply device) 31 Switching command tool (switching command means) 32 Charge detection sensor (charge state detection means) 33 Full charge notification means 34 Low charge notification means A Support mechanism B Traveling device C Control device (switching mechanism) E-Engine G Generator M Electric motor T Battery

Claims

1. 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.

2. 2. The work vehicle according to claim 1, wherein the engine speed is set to zero when the work vehicle is traveling in an area where the engine operation is restricted.

3. 2. A work vehicle as described in claim 1, wherein 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 and the boundary between the indoors and outdoors, and the area in which the operation of the engine is permitted is outdoors or an area outside the restrictive boundary.

4. 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.

5. 5. 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.

6. 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.

7. a charge state detection means for detecting a charge state of the battery is provided; 5. The work vehicle according to claim 4, wherein the switching mechanism switches from the first state to the second state when it determines, based on detection information from the charge state detection means, that the battery has become fully charged as a result of charging by operation of the engine.

8. A vehicle position determination means is provided for determining whether the vehicle is outdoors or indoors; 5. The work vehicle according to claim 4, 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 result of determination by the vehicle position determination means.

9. 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, 5. The work vehicle according to claim 4, wherein the switching mechanism switches from the first state to the second state at 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.

10. The vehicle is provided with a posture determination means for determining whether the vehicle is in a tilted posture state, 5. The work vehicle according to claim 4, wherein the switching mechanism switches to the first state if the vehicle is in an inclined position based on the result of determination by the position determination means, and switches to the second state if the vehicle is not in an inclined position.

11. 11. The work vehicle according to claim 1, further comprising an insufficient charge notification means for notifying the user that the battery has become insufficiently charged as a result of use of the electric motor.

12. a support mechanism for supporting the plurality of traveling devices on a vehicle body so that each traveling device can be raised and lowered; 11. 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.

13. 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 10, wherein the electric motor is configured to drive the hydraulic oil supply device.

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