Work vehicle

Abstract

To provide a work vehicle capable of preventing overload of a work machine during cruise control, and improving safety property.SOLUTION: A work vehicle includes a traveling vehicle body, a work machine, a traveling motor, a traveling motor controller, a working motor, a working motor controller, a battery, a vehicle controller, and a cruise control indication unit. In the work vehicle, the vehicle controller controls cruise control of the traveling vehicle body. The vehicle controller adjusts a vehicle speed during cruise control of the traveling vehicle body in accordance with a work load of the work machine, and starts cruise control only in advancing of the traveling vehicle body, and does not start cruise control in retreating and stopping of the traveling vehicle body.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a work vehicle. [Background technology]

[0002] BACKGROUND ART Conventionally, there is known a work vehicle equipped with a control system for the work vehicle that performs automatic steering operation (see, for example, Patent Document 1).

[0003] The control system includes a storage device that stores a target route for the work vehicle. The control system also includes a control device that controls steering of the work vehicle so that the work vehicle travels along the target route based on the position of the work vehicle identified by the positioning device and the target route stored in the storage device. The control device has a cruise control function that causes the work vehicle to travel at a reference speed set by the user. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2022-141259 Summary of the Invention [Problem to be solved by the invention]

[0005] Conventional cruise controls for work vehicles operate at a constant speed even when the work load of the work equipment is high, making them prone to overload. Furthermore, work vehicles are safer when cruise control is performed according to the driving conditions when moving forward, reversing, or stopped. However, the above-mentioned conventional technology does not disclose detailed control content of the cruise control, nor does it disclose control to prevent overload of the work equipment or control according to the driving conditions of the work vehicle.

[0006] The present invention has been made in view of the above, and has an object to provide a work vehicle that can prevent overloading of a work implement during cruise control and can improve safety. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems and achieve the object, the present invention provides a vehicle body (2), a working machine (3) attached to the vehicle body (2), a traveling motor (711) that drives the vehicle body (2), a traveling motor controller (110) that controls the driving of the traveling motor (711), a work motor (712) that drives the work machine (3), a work motor controller (120) that controls the driving of the work motor (712), a battery (72) that supplies power to the traveling motor (711) and the work motor (712), and a battery (72) that controls the driving of the traveling motor controller (110) and the work motor controller (120). A work vehicle (1) is provided with a vehicle controller (100) that controls a roller (120) and a cruise control instruction unit (283) that instructs the start of cruise control of the traveling body, and the vehicle controller (100) controls the cruise control of the traveling body (2), and the vehicle controller (100) adjusts the vehicle speed during cruise control of the traveling body (2) according to the work load of the work equipment (3), and starts cruise control only when the traveling body (2) is moving forward, and does not start cruise control when the traveling body (2) is moving backward or is stopped. [Effects of the Invention]

[0008] According to the charging system of the embodiment, it is possible to prevent overload of the work machine during cruise control and to improve safety. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing the overall configuration of a work vehicle according to an embodiment. [Figure 2] FIG. 2 is a block diagram showing an example of a control system in the work vehicle according to the embodiment. [Figure 3]FIG. 3 is a flowchart showing the processing procedure for cruise control according to the workload in the work vehicle according to this embodiment. [Figure 4] FIG. 4 is a block diagram showing an example of a control system in the work vehicle according to this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the work vehicle disclosed in the present application will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described below.

[0011] <Overall configuration of the work vehicle> The overall configuration of a work vehicle according to an embodiment will be described with reference to Figure 1. Figure 1 is a diagram showing the overall configuration of a work vehicle according to an embodiment. Note that Figure 1 also shows a schematic side (left side) view of a riding lawnmower 1. Note that in this embodiment, the riding lawnmower 1 will be used as an example of the work vehicle.

[0012] 1 also shows a three-dimensional Cartesian coordinate system including a Z-axis whose positive direction is vertically upward (upward). For ease of explanation, the positive direction of the X-axis will be defined as the left, the negative direction of the X-axis as the right, the positive direction of the Y-axis as the forward direction, and the negative direction of the Y-axis as the backward direction, with the X-axis direction being referred to as the left-right direction, the Y-axis as the front-back direction, and the Z-axis as the up-down direction.

[0013] The riding lawnmower 1 is driven by a driver to cut grass G1 and collect the cut grass G1. Note that, hereinafter, the riding lawnmower 1 or the traveling vehicle body 2 described below may be referred to as the "machine body."

[0014] As shown in Figure 1, the riding lawnmower 1 comprises a traveling body 2, a lawn mower (hereinafter referred to as mower) 3, a mower lifting mechanism 4, and a grass collection container (hereinafter referred to as collector) 5. The traveling body 2 comprises a body frame 21, a pair of left and right front wheels 22, and a pair of left and right rear wheels 23. The body frame 21 forms the body framework of the traveling body 2. A prime mover 71, which will be described later, is mounted on the body frame 21. The body frame 21 supports the pair of left and right front wheels 22 via a front axle case.

[0015] The body frame 21 also supports a transmission case 24 that houses a transmission, such as an HST (Hydro Static Transmission). The body frame 21 also supports a pair of left and right rear wheels 23 via a chain case that extends rearward from the transmission case 24.

[0016] In the riding lawnmower 1, the rotational power of the prime mover 71 is appropriately changed speed via the HST and transmitted to the left and right rear wheels 23 via a transmission mechanism housed in the transmission case 24 and chain case, and power is extracted from the transmission case 24 and transmitted to the left and right front wheels 22.

[0017] The traveling vehicle body 2 also includes a floor step 25 , a driver's seat 26 , a steering column 271 , a steering wheel 272 , various operating tools 281 , various operating pedals 282 , and a safety frame 29 .

[0018] The floor step 25 is provided at the front of the traveling vehicle body 2. The driver's seat 26 is a seat where the driver sits, and is provided at the rear of the floor step 25. The steering column 271 is provided at the front of the floor step 25. In other words, the steering column 271 is provided in front of the driver's seat 26. The steering wheel 272 is an operating tool for steering the vehicle body, and is provided at the top of the steering column 271.

[0019] The various operating devices 281 include a cruise control instruction unit 283 (see FIG. 2), a work output instruction unit 284 (see FIG. 2), a mower lifting / lowering lever, a collector lifting / lowering lever, a dump lever, etc., and are provided on the left and right sides of the driver's seat 26. The various operating pedals 282 include an accelerator pedal 285 (see FIG. 2), a brake pedal 286 (see FIG. 2), a clutch pedal, etc., and are provided above the floor step 25 and on the left and right sides of the steering column 271. The cruise control instruction unit 283 and the work output instruction unit 284 can be operating devices in any form, such as a lever or a switch.

[0020] The safety frame 29 is a member for ensuring the safety of the driver in the event of the machine tipping over, and is provided behind the driver's seat 26. The safety frame 29 is provided in an arch shape spanning the left and right directions of the machine when viewed from the front or rear.

[0021] The mower 3 is provided in front of the traveling vehicle body 2. In this way, the riding lawnmower 1 is a so-called front mower type, in which the mower 3 is provided at the front of the machine body. However, the riding lawnmower 1 may also be a so-called mid-mower type, in which the mower 3 is provided at the center of the machine body, for example.

[0022] The mower 3 is a work machine that cuts grass G1 growing in front of the mower 3, and includes a mower deck 31 and a cutting blade (not shown). The riding lawnmower 1 transports the grass clippings G2 cut by the cutting blade to a collector 5 (described below) via a duct 33 and a chute 34. In this case, the riding lawnmower 1 uses a blower 35 to blow and transport the grass clippings G2.

[0023] The mower lifting mechanism 4 includes a mower lifting cylinder 41 and a lift arm 42. The mower lifting cylinder 41 is, for example, a hydraulic cylinder, and drives the mower 3 to move up and down. The lift arm 42 is provided between the mower lifting cylinder 41 and the mower deck 31. The mower lifting mechanism 4 transmits the driving force of the mower lifting cylinder 41 to the lift arm 42, thereby driving the lift arm 42. The mower lifting mechanism 4 drives the lift arm 42 to move the mower 3 (mower deck 31) up and down.

[0024] The collector 5 is provided at the rear of the traveling vehicle body 2. The collector 5 is a container that stores the grass clippings G2 cut by the mower 3. The collector 5 is formed, for example, from a rectangular parallelepiped frame, and the front, rear, left, right, and top surfaces of the frame are made up of plate members with ventilation holes. An intake port (not shown) for the grass clippings G2 that communicates with the chute 34 is formed in the front of the collector 5.

[0025] The collector 5 includes a lid portion 51. The lid portion 51 is formed by integrating the rear and top surfaces of the collector 5. The lid portion 51 is configured to move away from the main body of the collector 5 in conjunction with the dump of the collector 5, leaving the rear of the collector 5 widely open. In this way, the collector 5 discharges the grass clippings G2 that have accumulated by dumping. In the riding lawnmower 1, the grass clippings G2 are basically discharged when the collector 5 is filled with grass clippings G2. When discharging the grass clippings G2, the riding lawnmower 1 moves to a predetermined discharge location and discharges the grass clippings G2 at the predetermined discharge location.

[0026] The riding lawnmower 1 also includes a prime mover 71, a battery 72, a vehicle controller 100 (see FIG. 2), and a display unit 62. As described above, the prime mover 71 is mounted on the vehicle body frame 21. The prime mover 71 drives the front wheels 22 and rear wheels 23, as well as the cutting blade of the mower 3, using rotational power. The riding lawnmower 1 includes a driving motor 711 (see FIG. 2) and a working motor 712 (see FIG. 2) as the prime mover 71. The battery 72 is provided, for example, on the traveling vehicle body 2 below the collector 5, and supplies power to the driving motor 711 and the working motor 712.

[0027] The vehicle controller 100 is capable of controlling each part through electronic control, and is equipped with a processing unit (not shown) having a CPU (Central Processing Unit) and the like, as well as a memory unit (not shown) consisting of a hard disk, ROM (Read Only Memory), RAM (Random Access Memory), and the like, in which various programs and necessary data are stored.

[0028] As will be described later, the vehicle controller 100 also controls the cruise control of the traveling vehicle body 2. Cruise control is a function that maintains the vehicle speed of the traveling vehicle body 2 at a set vehicle speed that is set by the driver.

[0029] The display unit 62 is provided on the upper part of the steering column 271. The display unit 62 is, for example, a liquid crystal monitor.

[0030] <Control content of the control system and control device for the work vehicle> Next, the control system in the riding lawnmower 1 according to the embodiment and the control details by the vehicle controller 100 will be described with reference to Fig. 2. Fig. 2 is a block diagram showing an example of a control system in the work vehicle according to the embodiment.

[0031] 2, a cruise control instruction unit 283, a work output instruction unit 284, an accelerator pedal 285, a brake pedal 286, and the like are connected to the vehicle controller 100. An accelerator pedal sensor 287 is provided for the accelerator pedal 285, and the opening degree of the accelerator pedal 285 is detected by the accelerator pedal sensor 287. A brake pedal sensor 288 is provided for the brake pedal 286, and the opening degree of the accelerator pedal 285 is detected by the brake pedal sensor 288.

[0032] The vehicle controller 100 receives an input of a cruise control start signal from a cruise control instruction unit 283. The vehicle controller 100 receives an input of a switching signal for switching the mower 3 on and off (between working state and non-working state) from a work output instruction unit 284. The vehicle controller 100 receives an input of the opening degree of an accelerator pedal 285 from an accelerator pedal sensor 287. The vehicle controller 100 receives an input of the opening degree of a brake pedal 286 from a brake pedal sensor 288.

[0033] Furthermore, the vehicle controller 100 is connected to a battery 72, a driving motor controller 110, a work motor controller 120, and the like.

[0034] The battery 72, the driving motor 711, and the like are connected to the driving motor controller 110. The driving motor controller 110 is capable of controlling the driving motor 711 by electronic control, and is provided with a processing unit (not shown) having a CPU and the like, and a storage unit (not shown) made up of ROM, RAM, and the like in which various programs and necessary data are stored.

[0035] A battery 72, a work motor 712, and the like are connected to the work motor controller 120. The work motor controller 120 is capable of controlling the work motor 712 by electronic control, and is equipped with a processing unit (not shown) having a CPU and the like, and a storage unit (not shown) made up of ROM, RAM, and the like in which various programs and necessary data are stored.

[0036] The traveling motor 711 uses rotational power to drive the traveling body 2. The work motor 712 uses rotational power to drive the mower 3. The vehicle controller 100 can control the speed of the traveling body 2 and the drive of the mower 3 by issuing output instructions to the traveling motor controller 110 and the work motor controller 120.

[0037] Therefore, by issuing an output command to the travel motor controller 110, the vehicle controller 100 can perform cruise control to maintain the speed of the traveling vehicle body 2. Furthermore, by separating the travel motor 711 and the work motor 712, the vehicle controller 100 can individually control the output of the travel motor 711 when the work load of the work motor 712 is high.

[0038] The vehicle controller 100 is configured to be able to initiate cruise control only when the vehicle is moving forward, and not when the vehicle is reversing or stopped. With the riding lawnmower 1, it is difficult for the operator to check the direction of travel of the traveling body 2 when the vehicle is moving backward, and there is a possibility that the traveling body 2 may start moving unintentionally when the vehicle is stopped. Therefore, by not performing cruise control when the vehicle is moving backward or stopped, the safety of the cruise control can be improved.

[0039] In cruise control, the vehicle controller 100 maintains the forward vehicle speed of the traveling vehicle body 2 at the time when the cruise control is turned on. The vehicle speed at this time is set based on the accelerator pedal sensor value (opening degree of the accelerator pedal 285) at the time when the cruise control is turned on. In other words, the vehicle controller 100 determines the vehicle speed for cruise control based on the operation of the cruise control instruction unit 283 and the accelerator pedal sensor value. This allows the vehicle controller 100 to maintain the vehicle speed while the traveling vehicle body 2 is traveling.

[0040] The vehicle controller 100 transmits the rotation speed of the driving motor 711 corresponding to the vehicle speed of the cruise control determined above to the driving motor controller 110. The driving motor controller 110 controls the speed of the driving motor 711 so as to maintain the transmitted rotation speed of the driving motor. This enables the driving motor controller 110 to control the vehicle speed of the traveling vehicle body 2 (the rotation speed of the driving motor 711).

[0041] When the accelerator pedal 285 is depressed while the cruise control is in operation, the vehicle controller 100 cancels the cruise control. In this way, the riding lawnmower 1 is configured so that the driver can cancel the cruise control simply by depressing the accelerator pedal 285.

[0042] Alternatively, the vehicle controller 100 cancels the cruise control when the brake pedal 286 is depressed while the cruise control is in operation. This allows the riding lawnmower 1 to be configured so that the driver can cancel the cruise control simply by depressing the brake pedal 286.

[0043] Alternatively, the vehicle controller 100 cancels the cruise control when the cruise control instructing unit 283 is operated during cruise control. In this way, the riding lawnmower 1 is configured so that the cruise control can be canceled by the driver operating the cruise control instructing unit 283.

[0044] The vehicle controller 100 is also configured to set a maximum vehicle speed at which cruise control can be applied, and performs cruise control within the set maximum vehicle speed (hereinafter referred to as the maximum vehicle speed for cruise control). This allows the riding lawnmower 1 to perform cruise control at a safe vehicle speed or below.

[0045] Furthermore, the vehicle controller 100 changes the control content of the cruise control in accordance with an instruction from the work output instruction unit 284. This allows the vehicle controller 100 to change the control content of the cruise control depending on whether work is being performed or not.

[0046] For example, when the work output is off (not working), the vehicle controller 100 performs cruise control within the maximum vehicle speed for cruise control. In this way, when the work output is off, the vehicle controller 100 does not adjust the vehicle speed because no load is placed on the work motor 712. When the work output is on (working), the vehicle controller 100 performs cruise control while applying load control that adjusts the vehicle speed according to the work load within the maximum vehicle speed for cruise control. In this way, because a load is placed on the work motor 712 when the work output is on, the vehicle controller 100 can prevent overload by adjusting the vehicle speed.

[0047] The vehicle controller 100 also determines (calculates) the workload based on the current value of the work motor 712. This allows the vehicle controller 100 to determine even the momentary workload based on the current value of the work motor 712. Alternatively, the vehicle controller 100 determines the workload based on the rotation speed of the work motor 712. This allows the riding lawnmower 1 to determine the workload from how the rotation speed of the work motor 712 drops. Alternatively, the vehicle controller 100 determines the workload based on the power of the work motor 712. This allows the vehicle controller 100 to determine the workload based on fluctuations in the power of the work motor 712. Alternatively, the vehicle controller 100 determines the workload based on the torque value of the work motor 712. This allows the riding lawnmower 1 to determine even the momentary workload based on the torque value.

[0048] The vehicle controller 100 sets a threshold value for determining whether the workload is high or not in the indicator for detecting the workload. This allows the vehicle controller 100 to determine the level of the workload based on the threshold value. For example, if the workload exceeds the threshold value, the vehicle controller 100 forcibly reduces the speed of the traveling vehicle body 2 until the workload falls below the threshold value. This allows the vehicle controller 100 to reduce the load on the work motor 712 by reducing the speed of the traveling vehicle body 2.

[0049] When forcibly decelerating the vehicle speed of the traveling vehicle body 2, the vehicle controller 100 continues to instruct the traveling motor controller 110 to maintain a constant deceleration rate until the workload decreases. By decelerating the traveling vehicle body 2 at a constant deceleration rate, the vehicle controller 100 can prevent shocks from occurring during deceleration. As will be described below, the thresholds may be set to a first threshold value and a second threshold value that is a workload threshold value smaller than the first threshold value.

[0050] Next, the cruise control according to the workload will be described with reference to Fig. 3. Fig. 3 is a flowchart showing the processing procedure for the cruise control according to the workload in the work vehicle according to this embodiment.

[0051] Conventional cruise control vehicles maintain a constant speed even when the work load is high, but the riding lawnmower 1 automatically adjusts the vehicle speed during cruise control to prevent overload, even without the operator's operation.

[0052] As shown in FIG. 3, the vehicle controller 100 determines whether the workload is greater than a first threshold value (step S101).

[0053] If the vehicle controller 100 determines in step S101 that the workload is equal to or less than the first threshold (step S101: No), the vehicle controller 100 determines whether the workload is greater than a second threshold (step S102).

[0054] If the vehicle controller 100 determines in step S102 that the workload is equal to or less than the second threshold (step S102: No), it restores the speed of the traveling vehicle body 2 to the set speed (step S103). In this way, when the high load determination is completed and the conditions for restoring the speed of the traveling vehicle body 2 are met, the vehicle controller 100 restores the speed of the traveling vehicle body 2 to the set speed of the cruise control. This causes the riding lawnmower 1 to automatically restore the speed of the traveling vehicle body 2 to the set speed. Note that when restoring the speed of the traveling vehicle body 2, the vehicle controller 100 increases the speed at a constant acceleration. This allows the vehicle controller 100 to prevent shocks from occurring when the speed is increased.

[0055] Next, the vehicle controller 100 determines whether or not a condition for continuing the cruise control is satisfied (step S104). The condition for continuing the cruise control is whether or not the cruise control has been released by the accelerator pedal 285 or the like.

[0056] If it is determined in step S104 that the continuation condition is not satisfied (step S104: No), the vehicle controller 100 ends the cruise control.

[0057] If the vehicle controller 100 determines in step S101 that the workload is greater than the first threshold (step S101: Yes), the vehicle controller 100 reduces the vehicle speed (step S105) and returns to step S101.

[0058] If the vehicle controller 100 determines in step S102 that the workload is greater than the second threshold (step S102: Yes), the vehicle controller 100 determines whether the load fluctuation is large (step S106).

[0059] In this way, by setting the threshold in two stages, the vehicle controller 100 can change the control according to the load stage. Furthermore, in a work vehicle equipped with multiple work modes that allow the maximum output of the work motor 712 to be changed, different first and second thresholds may be set for each work mode. This allows the vehicle controller 100 to control the cruise control with a workload that corresponds to the selected work mode. For example, the first and second thresholds may be set to be larger as the maximum output of the work motor 712 in the work mode increases.

[0060] In a work vehicle with multiple work modes that allow the maximum output of the work motor 712 to be changed, the deceleration and acceleration when decelerating and increasing the vehicle speed may be set to different values ​​for each work mode. This allows the vehicle controller 100 to control the cruise control with a workload that corresponds to the selected work mode. For example, the deceleration and acceleration when decelerating and increasing the vehicle speed may be set to larger values ​​as the maximum output of the work motor 712 in the work mode increases.

[0061] If the vehicle controller 100 determines in step S106 that the load variation per unit time is greater than the predetermined value (step S106: Yes), it decelerates the vehicle speed at a constant deceleration (step S105) and returns to step S101. As a result, when the workload is medium, the vehicle controller 100 can change the vehicle speed of the traveling vehicle body 2 in accordance with the load variation. When the load variation is large, the vehicle speed of the traveling vehicle body 2 decreases. The predetermined value is a value for determining whether the load variation is large or not, and is set in advance.

[0062] If the vehicle controller 100 determines in step S106 that the load variation per unit time is equal to or less than a predetermined value (step S106: No), the vehicle controller 100 does not increase the vehicle speed from the current vehicle speed (step S107) and returns to step S101. As a result, if the load variation is small, the vehicle speed of the traveling vehicle body 2 is maintained.

[0063] If it is determined in step S104 that the continuation condition is satisfied (step S104: Yes), the vehicle controller 100 returns to step S101.

[0064] As described above, when the work motor 712 reaches a threshold value for determining that the load is high during cruise control, the vehicle controller 100 reduces the speed of the traveling body 2. As a result, the riding lawnmower 1 automatically adjusts the speed of the traveling body 2 during cruise control to prevent overload, even without operation by the operator.

[0065] In step S105, the vehicle controller 100 may set a lower limit (lower limit vehicle speed) for reducing the vehicle speed of the traveling vehicle body 2, and may reduce the vehicle speed of the traveling vehicle body 2 to the lower limit vehicle speed. The lower limit vehicle speed may be a vehicle speed obtained by multiplying the set vehicle speed of the cruise control by a predetermined rate. When the set vehicle speed of the cruise control is 100%, the predetermined rate is set to a value smaller than 100% and larger than 0%. This allows the vehicle controller 100 to set a lower limit for reducing the vehicle speed. Furthermore, the vehicle controller 100 sets the lower limit vehicle speed according to the set vehicle speed of the cruise control.

[0066] Alternatively, the vehicle controller 100 may set the lower limit vehicle speed to a preset vehicle speed regardless of the set vehicle speed of the cruise control. The vehicle controller 100 maintains the preset lower limit vehicle speed until the high load determination is completed and the conditions for restoring the vehicle speed are met. This allows the vehicle controller 100 to decelerate the vehicle to a desired vehicle speed regardless of the set vehicle speed of the cruise control.

[0067] Furthermore, the vehicle controller 100 may set a threshold value (threshold value of the work motor 712) separate from the first threshold value and the second threshold value as a condition for restoring the vehicle speed of the traveling vehicle body 2. For example, the vehicle controller 100 sets a condition for restoring the vehicle speed, which is whether the vehicle speed falls below the threshold value of the work motor 712 for a certain period of time. The threshold value of the work motor 712 is set to a value smaller than the second threshold value. This allows the vehicle controller 100 to prevent frequent fluctuations in vehicle speed by providing hysteresis. Furthermore, the vehicle controller 100 can prevent frequent fluctuations in vehicle speed by restoring the vehicle speed when the load remains low.

[0068] Next, another configuration of the work vehicle will be described using Figure 4. Figure 4 is a block diagram showing an example of a control system in a work vehicle according to an embodiment. Note that the following description will focus on configurations and processes that are different from the configuration of the work vehicle described above, and descriptions of similar configurations and processes will be omitted.

[0069] As shown in FIG. 4, the various operating devices 281 (see FIG. 1) further include an acceleration change unit 289 and a set vehicle speed change unit 290. The acceleration change unit 289 and the set vehicle speed change unit 290 are connected to the vehicle controller 100. The vehicle controller 100 acquires the set acceleration from the acceleration change unit 289. The vehicle controller 100 acquires the set vehicle speed from the set vehicle speed change unit 290.

[0070] The vehicle controller 100 allows the operator to set cruise control settings (set acceleration, set vehicle speed) according to the load. This allows the riding lawnmower 1 to set detailed settings during cruise control according to the operator's preferences and the state of the field.

[0071] For example, the vehicle controller 100 can determine and adjust the deceleration to be applied when the load is high, based on the set acceleration acquired from the acceleration change unit 289. The vehicle controller 100 transmits the determined deceleration to the running motor controller 110. The running motor controller 110 controls the running motor 711 so that the transmitted deceleration is achieved. In this way, the vehicle controller 100 can adjust the responsiveness to avoid overload and the degree of shock during deceleration by changing the deceleration.

[0072] Furthermore, the vehicle controller 100 can determine and adjust the acceleration when restoring the vehicle speed based on the set acceleration acquired from the acceleration change unit 289. The vehicle controller 100 transmits the determined acceleration to the driving motor controller 110. The driving motor controller 110 controls the driving motor 711 so that the transmitted acceleration is achieved. In this way, the vehicle controller 100 can adjust the responsiveness of the vehicle speed restoration and the degree of shock when the vehicle speed increases by changing the acceleration.

[0073] Furthermore, the vehicle controller 100 can change the set vehicle speed of the cruise control during cruise control based on the set vehicle speed acquired from the set vehicle speed changing unit 290. This allows the vehicle controller 100 to change the set vehicle speed without canceling the cruise control. Also, the vehicle controller 100 can change the set vehicle speed using the set vehicle speed changing unit 290 according to the operator's preference.

[0074] As described above, the riding lawnmower 1 of this embodiment comprises the traveling body 2, the mower 3 attached to the traveling body 2, a traveling motor 711 that drives the traveling body 2, a traveling motor controller 110 that controls the drive of the traveling motor 711, a work motor 712 that drives the mower 3, a work motor controller 120 that controls the drive of the work motor 712, a battery 72 that supplies power to the traveling motor 711 and the work motor 712, a vehicle controller 100 that controls the traveling motor controller 110 and the work motor controller 120, and a cruise control instruction unit 283 that instructs the start of cruise control for the traveling body 2, and is a riding lawnmower 1 in which the vehicle controller 100 controls the cruise control of the traveling body 2, and the vehicle controller 100 adjusts the vehicle speed during cruise control of the traveling body 2 according to the workload of the mower 3, and starts cruise control only when the traveling body 2 is moving forward, and does not start cruise control when the traveling body 2 is moving backward or stopped.

[0075] This prevents the riding lawnmower 1 from becoming overloaded, saving energy and improving work efficiency. The riding lawnmower 1 also operates at a constant speed, preventing weed clogging and leaving grass uncut, enabling automatic operation while maintaining work quality close to that of a human driver. The riding lawnmower 1 also improves safety by starting cruise control only when the traveling vehicle body 2 is moving forward.

[0076] The riding lawnmower 1 also has a work output instruction unit 284 that switches the work output by the mower 3 on and off, and the vehicle controller 100 sets the maximum vehicle speed at which cruise control can be applied, performs cruise control within the set maximum vehicle speed, calculates the work load based on the current value of the work motor 712, and when the work output by the mower 3 is on, performs load control to adjust the vehicle speed within the maximum vehicle speed according to the calculated work load, and performs cruise control while applying load control.

[0077] As a result, when the work output of the riding lawnmower 1 is on, a load is placed on the work motor 712, but overload can be prevented by adjusting the vehicle speed. The riding lawnmower 1 can also determine the instantaneous work load based on the current value.

[0078] In addition, the vehicle controller 100 is set with a first threshold, which is a workload threshold, and a second threshold, which is a workload threshold smaller than the first threshold, and if the workload of the mower 3 exceeds the first threshold during cruise control, the vehicle speed is reduced at a constant deceleration rate, and if the workload of the mower 3 exceeds the second threshold during cruise control, the load fluctuation per unit time is calculated, and if the load fluctuation per unit time is greater than a predetermined value, the vehicle speed is reduced at a constant deceleration rate.

[0079] This allows the riding lawnmower 1 to determine the level of the workload based on the threshold value. Also, the riding lawnmower 1 can reduce the load on the work motor 712 by slowing down the speed of the traveling body 2.

[0080] In addition, the mower 3 has multiple work modes that allow the maximum output of the work motor 712 to be changed, and the vehicle controller 100 can change the deceleration and acceleration when slowing down and increasing the speed of the traveling vehicle body 2 to different values ​​for each work mode depending on the work load.

[0081] This allows the riding lawnmower 1 to control the load according to the selected mode.

[0082] In addition, the vehicle controller 100 can set a cruise control setting value according to the workload, and based on the setting value, can adjust the deceleration when the workload increases and the traveling vehicle body 2 slows down, and can adjust the acceleration when the workload decreases and the vehicle speed of the traveling vehicle body 2 returns to normal, and can change the cruise control setting vehicle speed during cruise control.

[0083] As a result, the riding lawnmower 1 can adjust the response to avoid overload and the level of shock when decelerating by changing the deceleration rate. Also, the riding lawnmower 1 can adjust the response to return to normal speed and the level of shock when increasing speed by changing the acceleration rate. Also, the riding lawnmower 1 can change the set vehicle speed without disabling the cruise control. Also, the riding lawnmower 1 can change the set vehicle speed using the set vehicle speed change unit 290 according to the operator's preferences.

[0084] Further advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. [Explanation of symbols]

[0085] 1. Riding lawn mower (work vehicle) 2 Running vehicle 3 Mower (working equipment) 72 Battery 100 Vehicle Controller 110 Driving motor controller 120 Work Motor Controller 283 Cruise control indicator 284 Work Output Instructions 711 Driving motor 712 Work Motor

Claims

1. A running vehicle body, a work machine attached to the traveling vehicle body; a driving motor that drives the traveling vehicle body; a driving motor controller that controls the driving of the driving motor; a work motor that drives the work machine; a work motor controller that controls the drive of the work motor; a battery that supplies power to the drive motor and the work motor; a vehicle controller that controls the driving motor controller and the working motor controller; a cruise control instruction unit that instructs the start of cruise control of the traveling vehicle body, A work vehicle in which the vehicle controller controls a cruise control of the traveling vehicle body, The vehicle controller adjusts the vehicle speed during cruise control of the traveling vehicle body according to the workload of the work equipment, and starts cruise control only when the traveling vehicle body is moving forward, and does not start cruise control when the traveling vehicle body is moving backward or stopped.

2. a work output instruction unit that switches on and off the work output of the work machine; The vehicle controller A maximum vehicle speed at which cruise control can be applied is set, and cruise control is performed within the set maximum vehicle speed, calculating a workload based on a current value of the work motor; The work vehicle according to claim 1, wherein when the work output from the work implement is on, load control is performed to adjust the vehicle speed within the maximum vehicle speed in accordance with the calculated work load, and cruise control is performed while applying the load control.

3. The vehicle controller a first threshold value that is a workload threshold value and a second threshold value that is a workload threshold value that is smaller than the first threshold value are set; When the workload of the work implement exceeds the first threshold workload during cruise control, the vehicle speed is reduced at a constant deceleration rate, 3. A work vehicle according to claim 1 or claim 2, wherein when the workload of the work implement exceeds the second threshold workload during cruise control, the load fluctuation per unit time is calculated, and when the load fluctuation per unit time is greater than a predetermined value, the vehicle speed is reduced at a constant deceleration rate.

4. The work machine has a plurality of work modes in which the maximum output of the work motor can be changed, 3. The work vehicle according to claim 1, wherein the vehicle controller is capable of changing the deceleration and acceleration of the traveling vehicle body to different values ​​when decelerating and accelerating the traveling vehicle body in accordance with the work load for each of the work modes.

5. The vehicle controller Cruise control settings can be set according to workload, Based on the set value, it is possible to adjust the deceleration when the work load increases and the traveling vehicle body is decelerated, and it is also possible to adjust the acceleration when the work load decreases and the vehicle speed of the traveling vehicle body is restored, 3. The work vehicle according to claim 1, wherein the set vehicle speed of the cruise control can be changed during the cruise control.

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