Electric work vehicle

Abstract

To highly efficiently consume energy.SOLUTION: An electric work vehicle comprises: a battery; a motor 29 which receives electric power supply from the battery and generates power; a travel device which is operated by power; a work power output portion (37, 38) which outputs power to be supplied to a work device performing work; a travel transmission system 41 which transmits power from the motor 29 to the travel device; a work transmission system 42 which transmits power from the motor 29 to the work power output portion (37, 38); a situation detection portion 52 which detects work travel situation; and a transmission control portion 54 which controls transmission states of the travel transmission system 41 and the work transmission system 42. The transmission control portion 54 performs power saving control for reducing electric power consumed by the motor 29 when the situation detection portion 52 detects that the work travel is a prescribed work travel situation.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an electric work vehicle in which a traveling device and a working device are driven by power generated by a motor. [Background technology]

[0002] As disclosed in Patent Document 1, a work machine (work vehicle, electric work vehicle) includes a battery unit (battery) and an electric motor (motor) that is driven by electricity stored in the battery unit. The work machine also includes a traveling device that drives the machine body, and a work device that performs a predetermined task can be attached and detached. The traveling device and the work device are driven by electricity generated by the electric motor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-099086 Summary of the Invention [Problem to be solved by the invention]

[0004] However, there is a limit to the amount of power that can be stored in a battery, and in order to drive for work efficiently, it is necessary to suppress power (energy) consumption.

[0005] An object of the present invention is to efficiently consume energy. [Means for solving the problem]

[0006] In order to achieve the above-mentioned objective, an electric work vehicle according to one embodiment of the present invention comprises a battery, a motor that receives power from the battery and generates power, a traveling device operated by the power, a work power output unit that outputs the power supplied to a work device performing work, a traveling transmission system that transmits the power from the motor to the traveling device, a work transmission system that transmits the power from the motor to the work power output unit, a situation detection unit that detects the situation of work traveling, and a transmission control unit that controls the transmission state of the traveling transmission system and the work transmission system, and when the situation detection unit detects that the work traveling is in a predetermined low work traveling situation, the transmission control unit performs power saving control to reduce the power consumed by the motor.

[0007] In a typical electric work vehicle, the motor operates at a predetermined rotation speed even when traveling at low speed, and the motor continues to operate at a predetermined rotation speed even when the operation of the work equipment is reduced or stopped.

[0008] According to the above configuration, in a low-work driving situation where driving or work is reduced, power saving control is performed to reduce the power consumption of the motor. This prevents the motor from operating more than necessary and consuming more power (energy) than necessary, allowing energy to be consumed efficiently.

[0009] The transmission control unit may reduce the power generated by the motor as the power saving control.

[0010] With this configuration, the power generated by the motor itself is reduced, so that power (energy) consumption can be suppressed with greater precision, and energy can be consumed more efficiently.

[0011] In addition, the power generated by the motor may be output via a drive shaft that rotates in response to the power, and the transmission control unit may reduce the rotation speed of the drive shaft as the power saving control.

[0012] With this configuration, the rotation speed of the propeller shaft that transmits rotational power to the traveling device and the working device is reduced, and the power transmitted to the traveling device and the working device is precisely controlled. As a result, the load on the motor is reduced, and the power (energy) consumed by the motor can be precisely controlled, resulting in efficient energy consumption.

[0013] The transmission control section may stop transmission of the power by the work transmission system when a predetermined first time has elapsed since the power was reduced.

[0014] With this configuration, power is not transmitted to the working device, so the load on the motor is reduced and the power (energy) consumed by the motor can be more accurately controlled, resulting in more efficient energy consumption.

[0015] The transmission control unit may stop transmission of the power by the work transmission system as the power saving control.

[0016] With this configuration, power is not transmitted to the working device, so the load on the motor is reduced and the power (energy) consumed by the motor can be more accurately controlled, resulting in more efficient energy consumption.

[0017] The transmission control section may stop the transmission of the power by the work transmission system by stopping the output of the power from the work power output section.

[0018] With this configuration, power is not transmitted to the working device, so the load on the motor is reduced and the power (energy) consumed by the motor can be more accurately controlled, resulting in more efficient energy consumption.

[0019] The low-work traveling state may be a state in which the transmission of power to the traveling device in the traveling transmission system is stopped.

[0020] A situation where the transmission of power to the traveling gear is stopped and traveling is not occurring is a situation where work traveling is not occurring or work is being performed with the machine stopped. At least, since traveling is not occurring, the need for power output from the motor is reduced.

[0021] With the above configuration, by performing power saving control when the vehicle is stopped and the need for power output from the motor is reduced, the power (energy) consumed by the motor can be reduced, allowing energy to be consumed efficiently.

[0022] In addition, the traveling transmission system may include a continuously variable transmission that changes the speed of the power, and may further include a traveling operation tool that accepts operations on the continuously variable transmission, and the low-work traveling condition may be a situation in which the traveling operation tool is operated to a position that operates the continuously variable transmission to a neutral position.

[0023] When the continuously variable transmission is operated to the neutral position, the vehicle is not traveling. With the above configuration, power saving control is performed when the vehicle is stopped and the need for power output from the motor is reduced, thereby reducing the power (energy) consumed by the motor and making the energy consumption more efficient.

[0024] The traveling transmission system may include a continuously variable transmission that changes a speed of the power, and the low-work traveling state may be a state in which the continuously variable transmission is in a neutral position.

[0025] When the continuously variable transmission is in the neutral position, the vehicle is not traveling. With the above configuration, power saving control is performed when the vehicle is stopped and the need for power output from the motor is reduced, thereby reducing the power (energy) consumed by the motor and allowing the energy to be consumed efficiently.

[0026] The vehicle may further include a work operating tool that receives an operation for the work device, and the low work traveling state may be a state in which the work operating tool has not been operated for a predetermined second time period or longer.

[0027] When the work operating tool is not operated for a predetermined time (second time) or more, it is highly likely that no work is being performed. In the work stop state where no work is being performed, the need for power output from the motor is reduced.

[0028] With the above configuration, by performing power saving control when work is stopped and the need for power output from the motor is reduced, the power (energy) consumed by the motor can be reduced, allowing energy to be consumed efficiently.

[0029] In addition, the work power output unit may be capable of attaching and detaching the work device, and may further include a sensor that detects whether or not the work device is attached to the work power output unit, and the transmission control unit may stop the power saving control when the sensor detects that the work device is attached to the work power output unit.

[0030] Even if the vehicle stops traveling and is in a low-working driving state, there are cases where work continues with the vehicle stopped. In such cases, if the power consumed by the motor is reduced, the power transmitted to the working device may be insufficient and the work may not be performed properly.

[0031] According to the above configuration, when no work is being performed and the driving condition is low-work, power-saving control is performed to reduce the power (energy) consumed by the motor, and when there is a possibility that work may continue, power-saving control is not performed, so that sufficient power can be secured to perform appropriate work as needed.

[0032] In addition, the motor may include a driving motor that drives the driving device and a work motor that drives the work device, and the transmission control unit may reduce the power generated by at least one of the driving motor and the work motor.

[0033] With this configuration, even in an electric work vehicle equipped with multiple motors, the motors are prevented from operating when not needed, thereby preventing more power (energy) than necessary, allowing energy to be consumed efficiently. [Brief description of the drawings]

[0034] [Figure 1] FIG. [Diagram 2] FIG. 2 is a left side view in vertical section showing the arrangement of a battery, a motor, etc. [Diagram 3] FIG. [Figure 4] FIG. 10 is a diagram illustrating a configuration for executing power saving control. [Diagram 5] FIG. 11 is a diagram illustrating a processing flow of power saving control. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] Below, we will explain about work vehicles (electric work vehicles) using a tractor as an example. In the following figures, F indicates the forward direction, B indicates the backward direction, U indicates the upward direction, D indicates the downward direction, F indicates the forward direction which is the forward direction, and B indicates the backward direction.

[0036] (Overall configuration of the tractor) As shown in Fig. 1, the machine body 3 has right and left front wheels 1 (corresponding to the running gear) and right and left rear wheels 2 (corresponding to the running gear). The tractor has a bonnet 4 at the front of the machine body 3, and a driver's section 5 at the rear of the machine body 3. The driver's section 5 has a steering wheel 6 for steering the front wheels 1, a driver's seat 7, and a rope frame 9.

[0037] As shown in Figures 1 and 2, the machine body 3 has right and left machine body frames 10, a continuously variable transmission 11, a transmission case 12, etc. The continuously variable transmission 11 is connected to the front part of the transmission case 12. The machine body frame 10 is provided along the front-to-rear direction, and the continuously variable transmission 11 and the transmission case 12 are connected to it. The front wheels 1 are attached to a front axle case 8 supported on the front part of the machine body frame 10. The rear wheels 2 are attached to the transmission case 12.

[0038] The transmission case 12 supports, at its rear portion, one top link 13 and right and left lower links 14 so that they can swing up and down. Right and left lift arms 15 are supported at the rear portion of the transmission case 12. A rod 16 is connected between the lift arms 15 and the lower links 14.

[0039] Various types of working equipment (not shown) can be attached to the top link 13 and the lower link 14. The working equipment is raised and lowered via the top link 13 and the lower link 14 as the lift arm 15 is swung up and down.

[0040] (Front loader configuration) 1, the tractor is equipped with a front loader 17 (corresponding to a working device) at the front of the machine body 3. The front loader 17 has a base 18, a boom 19, a bucket 20, a boom cylinder 21, a bucket cylinder 22, a frame 23, and the like.

[0041] The right and left bases 18 are connected to the machine frame 10, extend upward, and are disposed on the right and left sides of the rear of the bonnet 4. The right and left booms 19 are attached to the upper parts of the bases 18 so as to be able to swing up and down, and extend forward. The right and left boom cylinders 21 are attached across the bases 18 and the boom 19, and operate the boom 19 to raise and lower.

[0042] The bucket 20 is attached to the front of the boom 19 so as to be able to swing up and down. A frame 23 is connected across the right and left booms 19. A bucket cylinder 22 is connected across the bucket 20 and the frame 23, and the bucket 20 is operated for scooping and dumping by the bucket cylinder 22.

[0043] (Moore's composition) 1, the tractor has a mower 24 (corresponding to a working device) that can be attached to and detached from the machine frame 10. The mower 24 is disposed between the front wheels 1 and the rear wheels 2, and can be raised and lowered relative to the machine frame 10.

[0044] The mower 24 includes three blades (not shown) that are driven to rotate around an axis that extends in the up-down direction. The three blades are disposed inside the mower 24 so as to be aligned in the left-right direction.

[0045] (Front configuration of the aircraft) As shown in FIG. 2, the tractor includes, at the front of the machine frame 10, a battery 27, an inverter 28, a motor 29, a battery 33, and the like.

[0046] The right and left support members 25 are connected to the front part of the body frame 10, and a flat support frame 26 is connected to the support members 25. The battery 27 is provided inside the bonnet 4 and supported on the upper surface of the support frame 26.

[0047] The inverter 28 is attached to the front of the lower surface of the support frame 26. The motor 29 is attached to the rear of the lower surface of the support frame 26, and is disposed between the right and left aircraft frames 10.

[0048] The inverter 28 and the motor 29 are covered from below by a lower cover 30. The lower cover 30 is provided with a fan 31 in its front portion. The fan 31 introduces outside air into the inside of the lower cover 30, and the inverter 28 and the motor 29 are cooled by the outside air.

[0049] An arch-shaped frame 32 is connected across the right and left body frames 10, and is disposed at the rear end of the bonnet 4. A 12V battery 33 is supported by the frame 32.

[0050] The battery 27 supplies power to the inverter 28. The inverter 28 converts the DC power of the battery 27 into AC power and supplies it to the motor 29. The motor 29 is operated by receiving the AC power from the inverter 28.

[0051] Battery 27 supplies power to a DC-DC converter (not shown), and the DC-DC converter reduces the voltage of the supplied power to 12 V. The DC-DC converter supplies the power reduced to 12 V to battery 33. Various devices (not shown) equipped on the tractor are operated by the 12 V power from battery 33.

[0052] (Configuration of transmission system to front and rear wheels and mower) 2 and 3, power supplied from the motor 29 is transmitted to the front wheels 1 and the rear wheels 2 via a driving transmission system 41. The driving transmission system 41 includes the motor 29, a drive shaft 34 (input shaft), the continuously variable transmission 11, a transmission 44 mounted on the transmission case 12, a transmission shaft 35, and a transmission shaft 36.

[0053] The tractor includes a mid PTO shaft 37 (corresponding to a work power output section) and a rear PTO shaft 38 (corresponding to a work power output section). The mower 24 is detachably attached to the mid PTO shaft 37, and outputs power to the mower 24. The rear PTO shaft 38 outputs power to a work implement, and the work implement is detachably attached to the rear PTO shaft 38, the top link 13, and the lower link 14. Power supplied from the motor 29 is transmitted to the mid PTO shaft 37 and the rear PTO shaft 38 via a work transmission system 42. The work transmission system 42 includes the motor 29, the propeller shaft 34, a work transmission shaft 45, etc.

[0054] The power of the motor 29 is transmitted to the continuously variable transmission 11 via the drive shaft 34. The continuously variable transmission 11 has a hydraulic pump 11a and a hydraulic motor 11b. The continuously variable transmission 11 changes the speed of the power input to the hydraulic pump 11a and outputs it from the hydraulic motor 11b. The drive shaft 34 rotates according to the power of the mower 24. The power of the mower 24 is transmitted to the hydraulic pump 11a as the rotational power of the drive shaft 34 (input shaft). The continuously variable transmission 11 is configured as a hydrostatic type and is capable of continuously changing the speed between the forward and reverse sides. The operator can operate the continuously variable transmission 11 via a travel operating tool 56 (see FIG. 4) provided on the driver's unit 5.

[0055] The power changed in speed by the continuously variable transmission 11 is transmitted to the rear wheels 2 via a transmission 44 (auxiliary transmission) and a rear wheel differential (not shown) provided inside the transmission case 12. The power branches just before the rear wheel differential, and the branched power is transmitted via transmission shafts 35 and 36 to a front wheel differential (not shown) provided inside the front axle case 8, and then transmitted from the front wheel differential to the front wheels 1.

[0056] The mid PTO shaft 37 is provided facing forward at a lower part of the front part of the transmission case 12, and the rear PTO shaft 38 is provided facing backward at the rear part of the transmission case 12. Power transmitted by the propeller shaft 34, which is not subjected to speed change by the continuously variable transmission 11, is transmitted to the mid PTO shaft 37 and the rear PTO shaft 38 (hereinafter, these will be simply referred to as PTO shafts) via a work transmission shaft 45 branching off from the propeller shaft 34.

[0057] [Power saving control] Next, power saving control will be described using Figures 4 and 5 while also referring to Figure 3. The motor 29 of the electric tractor increases output (rotation speed) according to the traveling speed, and maintains a predetermined output (rotation speed) even when the tractor is not traveling. Power saving control is a control that optimizes the amount of power consumed by the motor 29 according to the working traveling situation, and reduces the power consumed by the motor 29 according to the power required for the working traveling.

[0058] The tractor (electric work vehicle) is equipped with a controller 50, which executes power saving control. The controller 50 is equipped with a processor such as a CPU, and is controlled by the processor. The controller 50 may be built into the ECU of the tractor, or may be mounted on the tractor separately from the ECU. The controller 50 is equipped with a situation detection unit 52 and a transmission control unit 54. The controller 50 may further include a storage unit, etc., as necessary.

[0059] The situation detection unit 52 detects at least one of the traveling situation and the work situation, and detects whether the work traveling is a predetermined low-work traveling situation. For example, the situation detection unit 52 detects a situation in which the machine body 3 is stopped during the work traveling as a low-work traveling situation.

[0060] Specifically, the situation detection unit 52 detects whether the continuously variable transmission 11 is in a neutral position or not, and if the continuously variable transmission 11 is in a neutral position, it determines that the vehicle 3 is stopped, which is an example of a low-work driving situation.

[0061] The transmission control unit 54 controls the transmission states of the traveling transmission system 41 and the work transmission system 42. As power saving control, when the situation detection unit 52 detects that the work traveling is in a predetermined low work traveling situation, the transmission control unit 54 reduces the power consumed by the motor 29. For example, in order to reduce the power consumed by the motor 29 as power saving control, the transmission control unit 54 reduces the power generated by the motor 29.

[0062] Specifically, first, the transmission control unit 54 judges whether the situation detection unit 52 has detected a low-work driving situation (step #1 in FIG. 5). When the situation detection unit 52 judges that a low-work driving situation has been detected (step #1 Yes in FIG. 5), the transmission control unit 54 controls the motor 29 to directly reduce the output (revolutions) of the motor 29 to reduce the power transmitted (step #2 in FIG. 5). In this way, in a situation where the driving is stopped and there is a high possibility that the driving is not being performed, the output (revolutions) of the motor 29 is reduced, thereby reducing the power consumed by the motor 29. As a result, the motor 29 is prevented from operating more than necessary and consuming more power (energy) than necessary, and the power consumption efficiency can be improved. And, by improving the power consumption efficiency, the tractor can extend the working time (working distance) and the traveling time (traveling distance).

[0063] Next, in the power saving control, when a predetermined first time has elapsed since the output (rotation speed) of the motor 29 was reduced, the transmission control unit 54 stops the transmission of power by the work transmission system 42. For example, the transmission control unit 54 stops the output of power from the PTO shaft (step #3 in FIG. 5). At this time, a clutch 48 may be provided on the work transmission shaft 45, and the transmission control unit 54 may control the clutch 48 to stop the rotation (transmission of power) of the work transmission shaft 45 and stop the output of power from the PTO shaft. The transmission control unit 54 may also stop the transmission of power by the work transmission system 42 by stopping the motor 29.

[0064] In a situation where traveling has stopped and it is highly likely that no work traveling is being performed, the transmission of power by the work transmission system 42 is stopped, so that no power is transmitted to the working device, and the output of the motor 29 can be reduced. As a result, the power consumed by the motor 29 is reduced, and the power consumption efficiency can be improved. In particular, by stopping the motor 29, the power consumption by the motor 29 can be almost eliminated, and therefore the power consumption can be significantly reduced.

[0065] In addition, by stopping the motor 29 or stopping the transmission of power by the work transmission system 42 after a predetermined first time has elapsed after the output (rotation speed) of the motor 29 is reduced, the worker can recognize this in advance before the motor 29 is stopped or the output of power from the PTO shaft is stopped. Therefore, the worker can select whether to continue the power saving control during the first time, or to stop the power saving control and continue the work. As a result, the work can be continued when the travel is stopped and the work is performed while suppressing the power consumed by the motor 29 as necessary. For this reason, it is preferable that the first time is set in advance as the time required for the worker to consider whether or not to continue the work and to take the predetermined measures.

[0066] [Another embodiment] (1) In the above embodiment, when the situation detection unit 52 determines that a low work driving situation has been detected, the transmission control unit 54 may stop the output of power from the PTO shaft (stop the rotation of the work transmission shaft 45) without reducing the output (rotation speed) of the motor 29.

[0067] This makes it possible to quickly reduce the power consumed by the motor 29, thereby improving the power consumption efficiency.

[0068] (2) In each of the above embodiments, the low-work driving state may be a state in which the transmission of power to the traveling device (at least one of the front wheels 1 and the rear wheels 2) in the traveling transmission system 41 is stopped. In other words, the low-work driving state may be a state in which power is not being transmitted to at least one of the transmission shafts 35 and 36.

[0069] The low work driving state may also be a state in which the continuously variable transmission 11 is in a neutral position. The state in which the continuously variable transmission 11 is in the neutral position may be detected directly by detecting the gear shift state of the continuously variable transmission 11, but may also be detected by a potentiometer or the like that detects the operating position of the traveling operation device 56, indicating that the traveling operation device 56 has been operated to a position that operates the continuously variable transmission 11 to the neutral position.

[0070] The work implements such as the front loader 17 and the mower 24 mounted on the electric work vehicle are operated by a work operation tool 57 provided on the driving unit 5. The low work traveling state may be a state in which no work is performed by the work implements for a predetermined second time or more. For example, the low work traveling state may be a state in which the work operation tool 57 has not been operated for a predetermined second time or more. The second time is set arbitrarily in advance.

[0071] As described above, by detecting the low-work driving state in a manner appropriate for the driving state, the low-work driving state that affects the power consumption can be detected with high accuracy. As a result, the power consumed by the motor 29 can be accurately suppressed, and the power consumption efficiency can be improved.

[0072] (3) In the above embodiment, instead of reducing the output (revolutions) of the motor 29, the transmission control unit 54 may reduce the rotation speed of the propeller shaft 34. That is, a speed change device 47 consisting of gears or the like is provided on the propeller shaft 34. The transmission control unit 54 may then control the speed change device 47 as power saving control to reduce the rotation speed of the propeller shaft 34, thereby reducing the power transmitted from the motor 29. It is difficult to efficiently transmit power from the hydraulic pump 11a to the hydraulic motor 11b. By reducing the rotation speed of the propeller shaft 34 that transmits power to the hydraulic pump 11a, the efficiency of power transmission from the hydraulic pump 11a to the hydraulic motor 11b can be improved, and the amount of power consumed can be reduced.

[0073] (4) Even when the machine body 3 is not traveling, work may be performed with the machine body 3 stopped. In such a case, even in a low work traveling condition, it is appropriate to maintain the power generated by the motor 29 and to maintain the power consumed by the motor 29.

[0074] Therefore, in each of the above embodiments, the transmission control unit 54 may stop performing power saving control in a situation where work is performed with the machine body 3 stopped.

[0075] Specifically, a sensor 58 is provided on the PTO shaft to detect whether or not a working device is attached, or whether or not the attached working device is a working device that may perform work with the machine body 3 stopped. Then, when the sensor 58 detects that a working device is attached, or when the sensor 58 detects that the attached working device is a working device that may perform work with the machine body 3 stopped, the transmission control unit 54 stops performing power saving control.

[0076] As a result, even in low work travel conditions, if work is carried out with the machine body 3 stopped, the power generated by the motor 29 can be maintained and work can be continued.

[0077] (5) In each of the above embodiments, the controller 50 is not limited to being configured from the above-mentioned functional blocks, and may be configured from any functional blocks. For example, each functional block of the controller 50 may be further subdivided, or conversely, some or all of the functional blocks may be combined. In addition, the functions of the controller 50 are not limited to the above-mentioned functional blocks, and may be realized by a method executed by any functional block. In addition, some or all of the functions of the controller 50 may be configured from software. A program related to the software is stored in any storage device and executed by a processor such as a CPU included in the controller 50 or a processor provided separately.

[0078] (6) In each of the above embodiments, the tractor does not have to include the front loader 17. In addition, the tractor does not have to include the mower 24. In other words, the tractor can be configured to be capable of detachably mounting any working implement. Furthermore, the tractor may be configured without either the mid PTO shaft 37 or the rear PTO shaft 38.

[0079] (7) In each of the above embodiments, the tractor is not limited to a configuration in which the traveling device and the working device are driven by one motor 29, and the tractor may be provided with a traveling motor that drives the traveling device and a working motor that drives the working device.

[0080] In this case, the transmission control section 54 reduces the power generated by at least one of the traveling motor and the working motor during power saving control.

[0081] (8) In each of the above embodiments, the present invention is not limited to a tractor (work vehicle) driven by a motor 29 powered by battery 27, but may be applied to a work vehicle driven by any prime mover, such as an engine powered by fuel. [Industrial Applicability]

[0082] The present invention can be applied not only to tractors but also to work vehicles that perform any type of work, such as agricultural work or civil engineering work. [Explanation of symbols]

[0083] 1 Front wheel (running gear) 2 Rear wheels (running gear) 11 Continuously variable transmission 11a Hydraulic pump 17 Front loader (work equipment) 24 Mower (working device) 27 Battery 29 Motor 34 Propulsion shaft (input shaft) 37 Mid PTO shaft (working power output part) 38 Rear PTO shaft (working power output part) 41 Driving transmission system 42 Work Transmission System 52 Situation detection section 54 Transmission control section 56 Traveling controls 57 Working tools 58 Sensors

Claims

1. A battery; A motor that receives power from the battery to generate power; A traveling device operated by the power; a working power output unit that outputs the power to be supplied to a working device that performs work; a drive transmission system that transmits the power from the motor to the drive device; a work transmission system that transmits the power from the motor to the work power output section; A situation detection unit that detects a situation of work travel; A transmission control unit that controls a transmission state of the traveling transmission system and the work transmission system, The transmission control unit performs power saving control to reduce the power consumed by the motor when the condition detection unit detects that the work driving is in a predetermined low work driving condition.

2. The electric work vehicle according to claim 1 , wherein the transmission control section reduces the power generated by the motor as the power saving control.

3. The power generated by the motor is output via a drive shaft that rotates in response to the power, The electric work vehicle according to claim 2 , wherein the transmission control section reduces the rotation speed of the drive shaft as the power saving control.

4. The electric work vehicle according to claim 2 , wherein the transmission control section stops the transmission of the power by the work transmission system when a predetermined first time has elapsed since the power was reduced.

5. The electric work vehicle according to claim 1 , wherein the transmission control section stops the transmission of the power by the work transmission system as the power saving control.

6. The electric work vehicle according to claim 4 or 5, wherein the transmission control section stops the transmission of the power by the work transmission system by stopping the output of the power from the work power output section.

7. The electric work vehicle according to claim 1 , wherein the low-work-load driving state is a state in which the transmission of power to the traveling device in the driving transmission system is stopped.

8. The traveling transmission system includes a continuously variable transmission that changes the speed of the power, Further comprising a travel operating tool that receives an operation for the continuously variable transmission, The electric work vehicle according to claim 1 , wherein the low-work-duty driving state is a state in which the driving operating tool is operated to a position that operates the continuously variable transmission to a neutral position.

9. The traveling transmission system includes a continuously variable transmission that changes the speed of the power, The electric work vehicle according to claim 1 , wherein the low work driving state is a state in which the continuously variable transmission is in a neutral position.

10. Further, a work operation tool is provided for receiving an operation for the work device, The electric work vehicle according to claim 1 , wherein the low work traveling state is a state in which the work operating tool has not been operated for a predetermined second time or longer.

11. the working power output unit is capable of detachably mounting the working device, a sensor for detecting whether the working device is attached to the working power output unit, The electric work vehicle according to claim 1 , wherein the transmission control section stops the power saving control when the sensor detects that the work device is attached to the work power output section.

12. The motor includes a travel motor that drives the travel device and a work motor that drives the work device, The electric work vehicle according to claim 2 , wherein the transmission control section reduces the power generated by at least one of the travel motor and the work motor.

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