Work vehicles

Abstract

To provide a work vehicle that can further improve power consumption by preventing the battery from discharging when it is not necessary to discharge it.SOLUTION: In a work vehicle 1, its main controller 8 turns off a relay 33 via a sub-controller 9 to stop power supply from the battery 49 to a first drive part 15 when a set time T1 has elapsed without any input operation from the time when a lock lever 5c is raised and the operation of a working device 7 by an operating lever 5a is disabled.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] Conventionally, a hydraulic excavator has been proposed that stops the prime mover if the working device has not been operated for a predetermined period of time (Patent Document 1: JP 2022-104124 A). Also, an electric excavator has been proposed that stops the drive source when a locking operation that disables operation of the control lever is received (Patent Document 2: JP 2023-070976 A). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-104124 [Patent Document 2] Japanese Patent Publication No. 2023-070976 Summary of the Invention [Problem to be solved by the invention]

[0004] Electric motors are quieter than engines, and it can be difficult to tell whether they are powered or not. Therefore, the battery may continue to supply power, and if the battery continues to supply power even when the operator is not present, the battery In situations where there is no need to discharge There is a problem in that the discharge increases the amount of unnecessary energy consumption. [Means for solving the problem]

[0005] The present invention has been made in view of the above circumstances, and provides a battery In situations where there is no need to discharge The object is to provide a work vehicle that can further improve electricity efficiency by preventing discharge.

[0006] In one embodiment, the above problem is solved by the solution disclosed below.

[0007] The work vehicle according to the present invention includes a plurality of hydraulically operated working devices, a drive unit that drives the working devices, a battery, a battery management system that controls the power supply to the battery, a relay, and a contactor; A main controller, a sub-controller, a plurality of operation levers, and a lock lever , display section, and operation switch section Equipped with The drive unit has an electric motor and an inverter that supplies power to the electric motor, and when a set time has elapsed from the point in time when the lock lever is raised and the operation of the working device by the operating lever is disabled without any input operation on either the display unit or the operation switch unit, the main controller turns off the relay via the sub-controller, and the battery management system turns off the contactor to stop the supply of power from the battery to the drive unit. do.

[0009] With this configuration, the machine shuts down when the set time has elapsed without any input operation on the display unit, operation switch unit, etc. This prevents the battery from continuing to supply power when the operator is absent.

[0010] As an example, The aforementioned When the lock lever is down and the start switch is pressed, The main controller Through the sub-controller The aforementioned Turn on the relay The battery management system turns on the contactor The battery starts supplying power to the drive unit, and when the passcode is authenticated, The main controller Enables the operation of the working device by the operating lever The main controller displays a countdown on the display unit when the operation of the working device is enabled, and maintains the on state of the relay when the input operation is performed within the period until the set time is reached. do. [Effects of the Invention]

[0012] According to the present invention, a battery In situations where there is no need to discharge By preventing discharge, a work vehicle can be realized that can further improve power consumption. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a schematic perspective view showing an example of a work vehicle according to this embodiment. [Figure 2] FIG. 2 is a schematic circuit diagram showing an example of a drive control system in the work vehicle shown in FIG. [Figure 3] FIG. 3 is a simplified circuit diagram showing an example of a control system around the start switch in FIG. [Figure 4] FIG. 4 is a schematic flowchart illustrating an example of a control procedure in the work vehicle shown in FIG. [Figure 5] FIG. 5 is a schematic timing chart showing a first example of a control operation in the working vehicle shown in FIG. [Figure 6] FIG. 6 is a schematic timing chart showing a second example of the control operation in the working vehicle shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram showing an example of a work vehicle 1 according to this embodiment, and is a perspective view from above the left rear. Here, a hydraulic excavator will be used as an example. As an alternative to the above configuration, the work vehicle 1 may also be a track loader or a carrier. In all drawings used to explain the embodiment, members having the same function are given the same reference numerals, and repeated description thereof may be omitted.

[0015] As shown in Fig. 1, the work vehicle 1 comprises a travelling lower body 2 and a swiveling upper body 3 disposed on the lower body 2. The lower body 2 has a traveling device 6a, and the upper body 3 has a cab 4. Here, the part surrounded by the dashed line P1 in the figure is a schematic structural diagram showing the main parts of the cab 4.

[0016] As an example, the traveling device 6a is equipped with a pair of left and right crawlers. The traveling device 6a has a traveling hydraulic motor 17a for the left traveling body and a traveling hydraulic motor 17b for the right traveling body. As an alternative to the above configuration, the traveling device may be equipped with tires.

[0017] The work vehicle 1 has a battery 49 that supplies power. The battery 49 is built into the battery pack 47. The work vehicle 1 has a display unit 98. The display unit 98 is configured to be able to display operation information of the first drive unit 15 and the second drive unit 16, remaining capacity information of the battery pack 47, and other known vehicle information. The work vehicle 1 is also equipped with an on-board charger (not shown).

[0018] As an example, the cab 4 has a seat 4a where the operator gets in and sits, a lock lever 5c disposed on the left side of the seat 4a, and a display unit 98 disposed on the right side of the seat 4a. In addition, the cab 4 has operation levers 5a disposed on the left and right sides of the seat 4a.

[0019] For example, a seat switch 5d is located below the seat 4a, and a start switch 4b is located to the right of the seat 4a. The seat switch 5d is a mechanical switch or a pressure-sensitive switch that is activated by the weight of the operator when he or she sits on the seat 4a. The start switch 4b is a push-button switch that can be used for both start and stop.

[0020] As an example, an operation switch unit 99 is disposed on the right side of the seat 4a. As an example, the operation switch unit 99 includes one or more of a jog dial, a tactile switch, a lever switch, a push switch, a pressure-sensitive switch, and a touch panel.

[0021] As an example, the operation switch unit 99 includes one or more of an eco mode selection switch, a lift alarm activation switch, a beacon switch, a detent switch, a deceleration switch, a light switch, a wiper switch, and a washer switch.

[0022] The work vehicle 1 has a plurality of working devices 7. Each of the plurality of working devices 7 is operated by hydraulic pressure (hydraulic oil at a predetermined pressure).

[0023] The working device 7 includes, for example, a blade 51a. The blade 51a is swung up and down by a blade cylinder 18a relative to the lower body 2. The arm 51c is swung up and down by an arm cylinder 18b relative to the boom 51b.

[0024] The working device 7, for example, has a boom 51b, an arm 51c, and an attachment 51d. The boom 51b is attached to the upper body 3 so as to be swingable in the vertical direction, including the up-down direction and a front-to-back component. The arm 51c is attached to the boom 51b so as to be swingable in the vertical direction, including the up-down direction and a front-to-back component. The attachment 51d is attached to the arm 51c so as to be swingable in the vertical direction, including the up-down direction and a front-to-back component.

[0025] As an example, the attachment 51d is a bucket, which is swung up and down relative to the arm 51c by a bucket cylinder 18c. As an example, the boom 51b is swung up and down relative to the upper body 3 by a boom cylinder, and is swung left and right relative to the upper body 3 by a swing cylinder (not shown).

[0026] Figure 2 is a schematic circuit diagram showing an example of a drive control system in the work vehicle 1. The work vehicle 1 is equipped with a first drive unit 15 that supplies hydraulic oil at a predetermined pressure to a traveling hydraulic motor 17a, a traveling hydraulic motor 17b, a blade cylinder 18a, an arm cylinder 18b, and a bucket cylinder 18c. Note that the circuit diagram in Figure 2 omits some parts other than essential parts.

[0027] The work vehicle 1 is equipped with a slewing device 6b operated by a second drive unit 16. As an example, the second drive unit 16 has an electric motor for slewing 16a to which a reducer 16c is attached, and a pinion gear of the reducer 16c meshes with a slewing bearing of the lower body 2 (not shown).

[0028] 2 and 3, the work vehicle 1 has a battery pack 47. The battery pack 47 is detachably attached to the work vehicle 1. As an example, the battery pack 47 has a battery management system 48, a battery 49, and a contactor 34.

[0029] As an example, the battery 49 is a lithium ion battery made up of multiple cells. As an example, the battery 49 The power supply voltage is 60The voltage is about 800 V. The battery pack 47 has various sensors built in, and the wiring diagram for these sensors is omitted in the figure. As an example, the work vehicle 1 has a lead battery 46 that supplies power to a battery management system 48 when the work vehicle 1 is started.

[0030] The work vehicle 1 starts up when the operator presses the start switch 4b. The work vehicle 1 has a main controller 8 (vehicle controller) and a sub-controller 9 (switch assembly controller). When the start switch 4b is pressed, the main controller 8 sends a power supply start signal to the sub-controller 9, and the sub-controller 9 that receives the power supply start signal turns on the relay 33.

[0031] Then, when relay 33 is turned on, battery management system 48 turns on contactor 34. When contactor 34 is turned on, power supply from battery 49 to first drive unit 15 and second drive unit 16 begins. After power supply begins, the operator operates operating lever 5a to operate traveling device 6a, swing device 6b, and work device 7.

[0032] When the operator operates the control lever 5a, an operation signal is sent to the main controller 8, and the main controller 8, upon receiving the operation signal, activates the first drive unit 15 and the second drive unit 16. The Controller Area Network (CAN) is used as the communication protocol for vehicle control including the main controller 8 and the sub-controller 9. As an example, the relay 33 is an ACC relay attached to the accessory power supply.

[0033] The first drive unit 15 has a first hydraulic pump 22a that sucks in and discharges hydraulic oil stored in a hydraulic oil tank 54. The first drive unit 15 also has a first electric motor 21a that drives the first hydraulic pump 22a, and a first inverter 25a that supplies power to the first electric motor 21a in response to a command from the main controller 8.

[0034] The first drive unit 15 has a second hydraulic pump 22b that sucks in and discharges hydraulic oil stored in a hydraulic oil tank 54. The first drive unit 15 also has a second electric motor 21b that drives the second hydraulic pump 22b, and a second inverter 25b that supplies power to the second electric motor 21b in response to a command from the main controller 8.

[0035] As an example, the first drive unit 15 is configured to merge the first output portion of the first hydraulic pump 22a and the second output portion of the second hydraulic pump 22b to send hydraulic oil to the primary side of the control valve unit 10.

[0036] In the control valve unit 10, the primary sides of a plurality of control valves are connected in parallel. In the example of Fig. 2, the primary sides of hydraulic motor control valves 11a and 11b and hydraulic cylinder control valves 12a, 12b, and 12c are connected in parallel. Here, the number of various control valves constituting the control valve unit 10 may increase or decrease.

[0037] The control valve unit 10 has a relief valve 43, and the primary side of the relief valve 43 is connected in parallel to the primary side of each control valve. The secondary side of the relief valve 43 forms a return flow path, and hydraulic oil exceeding the set pressure is returned to the hydraulic oil tank 54.

[0038] As an example, the primary side of a first check valve 41a is connected to the output side of the first hydraulic pump 22a, and the primary side of a second check valve 41b is connected to the output side of the second hydraulic pump 22b. The secondary sides of the first check valve 41a and the second check valve 41b join together and are connected to the primary side of the control valve unit 10. As an example, the first hydraulic pump 22a and the second hydraulic pump 22b are both fixed displacement gear pumps. As an example, the first electric motor 21a and the second electric motor 21b are both interior permanent magnet motors.

[0039] The first driving unit 15 has a rotation speed sensor 45a that detects the rotation speed of the first electric motor 21a and a rotation speed sensor 45b that detects the rotation speed of the second electric motor 21b. The first driving unit 15 also has a temperature sensor 44 that detects the temperature of the hydraulic oil stored in the hydraulic oil tank 54.

[0040] The second drive unit 16 has a swing electric motor 16a to which a reducer 16c is attached, and a swing inverter 16b that supplies power to the swing electric motor 16a in response to a command from the main controller 8. The second drive unit 16 has a rotation speed sensor 45c that detects the rotation speed of the swing electric motor 16a.

[0041] As an example, the operator's cab 4 is provided with an air conditioner 26. The air conditioner 26 has an air conditioner electric motor 26a and an air conditioner inverter 26b that supplies power to the air conditioner electric motor 26a in response to a command from the main controller 8.

[0042] Figure 4 is a simplified schematic flowchart showing an example of the control procedure by the main controller 8 and sub-controller 9 in the work vehicle 1. The control procedure shown in Figure 4 consists of steps S1 to S9. The control procedure in the work vehicle 1 will now be described below.

[0043] In step S1 of Fig. 4, when the start switch 4b is pressed, the main controller 8 sends a power supply start signal to the sub-controller 9. Then, the sub-controller 9, which has received the power supply start signal, turns on the relay 33. When the relay 33 is turned on, power supply from the battery 49 to the first drive unit 15 and the second drive unit 16 begins. When power supply begins, the process proceeds to step S2.

[0044] 4, the main controller 8 displays a passcode entry screen on the display unit 98. When the passcode entry screen is displayed, the process proceeds to step S3.

[0045] 4, the main controller 8 authenticates the passcode entered by the operator. If the main controller 8 authenticates the passcode, the process proceeds to step S4. On the other hand, if the main controller 8 does not authenticate the passcode, the process returns to step S2 and the passcode entry screen is redisplayed. Alternatively, the process returns to step S2 and the passcode entry screen is redisplayed while displaying an error message.

[0046] 4, the main controller 8 determines whether the lock lever 5c is lowered. If the main controller 8 determines that the lock lever 5c is lowered, the process proceeds to step S5. On the other hand, if the main controller 8 determines that the lock lever 5c is not lowered, the process returns to step S4.

[0047] In step S5 of FIG. 4, the main controller 8 starts operating the first driving unit 15 and the second driving unit 16, enables the operation of the plurality of operating levers 5a, and then proceeds to step S6.

[0048] 4, the main controller 8 determines whether the lock lever 5c is raised. If the main controller 8 determines that the lock lever 5c is raised, the process proceeds to step S7. On the other hand, if the main controller 8 determines that the lock lever 5c is not raised, the process returns to step S6.

[0049] 4, the main controller 8 stops the operation of the first drive unit 15 and the second drive unit 16, disables the operation of the operating lever 5a, displays a countdown on the display unit 98, and then proceeds to step S8. The countdown display will be described later.

[0050] 4, the main controller 8 determines whether the set time T1 has elapsed. If the main controller 8 determines that the set time T1 has elapsed, the process proceeds to step S9. On the other hand, if the main controller 8 determines that the set time T1 has not elapsed, the process returns to step S8.

[0051] 4, the main controller 8 transmits a power supply stop signal to the sub-controller 9. Then, upon receiving the power supply stop signal, the sub-controller 9 turns off the relay 33. When the relay 33 is turned off, power supply from the battery 49 to the first drive unit 15 and the second drive unit 16 is stopped.

[0052] Next, a timing chart showing the outline of drive control in the work vehicle 1 will be explained below.

[0053] 5 is a timing chart of Example 1. Example 1 shows that power supply to the first drive unit 15 and the second drive unit 16 is stopped when a set time T1 has elapsed without any input operation from the time when operation of the working device 7 by the operating lever 5a is disabled.

[0054] 6 is a timing chart of the second example. The second example is an example in which an input operation is performed before the set time T1 has elapsed since the operation of the working device 7 by the operating lever 5a was disabled. The second example shows that power supply to the first drive unit 15 and the second drive unit 16 is stopped when the set time T1 has elapsed since the last input operation was not performed.

[0055] In step S7 of FIG. 4, if an input operation is performed before the set time T1 has elapsed, the main controller 8 resets the count toward the set time T1 and starts the count from the point in time when the input operation was performed.

[0056] According to this configuration, the relay 33 is maintained in the on state by the operator operating the touch panel or operation buttons of the display unit 98 or by operating the various switches of the operation switch unit 99. Then, the machine is not automatically shut down, and the count toward the set time T1 is restarted from zero. This allows for flexible response according to the operator's work situation, resulting in a configuration that is easier to use.

[0057] The countdown display is, for example, performed by lighting an icon, blinking an icon, or changing the color of the icon, for example, from yellow to red, on a predetermined screen of the display unit 98.

[0058] As an example, when the countdown to the set time T1 starts, the main controller 8 lights up the icon. After that, when one minute has passed since the start of the countdown to the set time T1, the main controller 8 makes the icon blink. The set time T1 can be changed using the service tool.

[0059] As an example, in step S2 of FIG. 4, whether or not to perform auto-shutdown can be stored in the database for each passcode of the logged-in user, and the conditions can be carried over the next time the device is started up.

[0060] In addition to the above-described configuration, when the set time T1 has elapsed with no input operation and the seat switch 5d not being activated, the power supply from the battery 49 to the first drive unit 15 and the second drive unit 16 can also be stopped.

[0061] In addition to the above configuration, if the sheet switch 5d is activated before the set time T1 has elapsed, the countdown toward the set time T1 can be reset and the countdown can be restarted from the point at which the sheet switch 5d was activated.

[0062] According to the work vehicle 1 of the present embodiment described above, it is possible to further improve the electricity consumption of the first electric motor 21a and the second electric motor 21b. Furthermore, limiting the time that power is supplied to the first electric motor 21a and the second electric motor 21b when no predetermined input operation is performed also further improves safety.

[0063] The drive source of the work vehicle 1 is not limited to the above configuration, and may be configured to use an engine in addition to an electric motor. The battery of the work vehicle 1 is also not limited to the above configuration, and known secondary batteries such as nickel-metal hydride batteries can be used. In this way, the work vehicle 1 may be modified as appropriate to suit the specifications, etc. [Explanation of symbols]

[0064] 1. Work vehicles 2 Lower body 3. Upper body 4 Driver's cab, 4a Seat, 4b Start switch 5a Operating lever, 5c Lock lever 6a Running gear, 6b Swivel gear 7 Work equipment 8 Main controller (vehicle controller) 9 Sub-controller (switch assembly controller) 10 Control valve unit 11a, 11b Hydraulic motor control valve 12a, 12b, 12c Control valves for hydraulic cylinders 15 First drive unit 16 second drive unit, 16a electric motor for turning, 16b inverter for turning 17a, 17b Hydraulic motor for travel 18a Blade cylinder (hydraulic cylinder) 18b Arm cylinder (hydraulic cylinder) 18c Bucket cylinder (hydraulic cylinder) 21a first electric motor, 21b second electric motor 22a First hydraulic pump, 22b Second hydraulic pump 25a First inverter, 25b Second inverter 26 Air conditioner, 26a Electric motor for air conditioner, 26b Inverter for air conditioner 33 Relay 34 Contactor 41a First check valve, 41b Second check valve 43 Relief valve 44 Temperature Sensor 45a, 45b, 45c RPM sensors 46 Lead-acid battery 47 Battery Pack 48 Battery Management System (BMS) 49 Battery (Lithium-ion battery) 51a blade, 51b boom, 51c arm, 51d attachment (bucket) 54 Hydraulic oil tank 98 Display unit 99 Operation switch section T1 Setting time

Claims

1. The device comprises a plurality of hydraulically operated working devices, a drive unit that drives the working devices, a battery, a battery management system that controls the power supply from the battery, a relay, a contactor, a main controller, a sub-controller, a plurality of operation levers, a lock lever, a display unit, and an operation switch unit, and the drive unit has an electric motor and an inverter that supplies power to the electric motor, and when a set time has elapsed from the point in time when the lock lever is raised and the operation of the working devices by the operation lever is disabled with no input operation being performed on either the display unit or the operation switch unit, the main controller turns off the relay via the sub-controller, and the battery management system turns off the contactor to stop the power supply from the battery to the drive unit. A work vehicle characterized by:

2. When the lock lever is down and the start switch is pressed, the main controller turns on the relay via the sub-controller, the battery management system turns on the contactor and starts supplying power from the battery to the drive unit, and when the passcode is authenticated, the main controller enables operation of the work device using the operation lever, and when operation of the work device is enabled, the main controller displays a countdown on the display unit, and when there is an input operation within the period until the set time is reached, maintains the on state of the relay.

2. The work vehicle according to claim 1,

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