Patent Application
20250033488
The present invention relates to electric work vehicles including travel devices driven by motors.
As disclosed in Japanese Unexamined Patent Application Publication No. 2013-150560, an electric tractor (an electric work vehicle) includes a travel device and a work vehicle both driven by a motor. The electric work vehicle such as an electric tractor includes various operation tools, and the motor or the like is controlled based on an operation on the various operation tools such that the electric work vehicle travels and works.
However, the motor can stand by at a rotation speed of 0 rpm, and when an operation is performed in a wrong procedure with the motor being at the rotation speed of 0 rpm, a body of the electric work vehicle may suddenly move or may not be able to start traveling or working appropriately.
Example embodiments of the present invention provide electric work vehicles that each can start traveling or working appropriately even while a motor is at a rotation speed of 0 rpm or rotates minutely.
An electric work vehicle according to an example embodiment of the present invention includes a motor to drive at least either a travel device or a work device, at least one shift operation tool to shift a rotational power to drive the travel device or the work device, an accelerator operation tool to raise and lower a motor rotation speed of the motor, and a motor controller configured or programmed to control the motor rotation speed in response to an operation on the accelerator operation tool and to perform a motor restraining control to restrict an output from the motor in response to the at least one shift operation tool and the accelerator operation tool being operated in an inappropriate procedure with the motor rotation speed being equal to or less than a predetermined first rotation speed.
At the time when a body is to be moved, when the shift operation tool and the accelerator operation tool are operated in an inappropriate procedure while the motor is in operation at a low rotation speed, the body might suddenly move due to an increase in the motor rotation speed of the motor. In the meantime, at the time when a work device is to be operated, when the shift operation tool and the accelerator operation tool are operated in an inappropriate procedure while the motor is in operation at a low rotation speed, the work device might suddenly work due to an increase in the motor rotation speed of the motor.
In the above configuration, an increase of the output from the motor is restricted by the motor restraining control. Accordingly, even when the shift operation tool and the accelerator operation tool are operated in an inappropriate procedure, it is possible to restrain the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
The motor restraining control may be a control to restrict an increase in the motor rotation speed.
With such a configuration, due to the motor restraining control, it is possible to restrict (restrain) an increase in the motor rotation speed and to easily and appropriately restrict an output from the motor, so that travel or work can be started appropriately.
The motor restraining control may be a control to restrict an increase in a torque of the motor.
With such a configuration, due to the motor restraining control, it is possible to restrict (restrain) an increase in the torque of the motor and to easily and appropriately restrict an output from the motor, so that travel or work can be started appropriately.
The motor controller may be configured or programmed to perform the motor restraining control in response to the accelerator operation tool being operated after the at least one shift operation tool is operated with the motor rotation speed being equal to or less than the first rotation speed.
When the shift operation tool is operated after the accelerator operation tool moderately raises the motor rotation speed, an increasing speed of the rotational power is relieved moderately by a power transmission mechanism to transmit power from the motor to the travel device or the work device. On the other hand, when the motor rotation speed is raised by the accelerator operation tool after the shift operation tool is operated, power is rapidly (directly) transmitted from the motor to the travel device or the work device, so that the body might suddenly move or the work device might suddenly work.
Accordingly, by performing the motor restraining control at the time when the accelerator operation tool is operated after the shift operation tool is operated, it is possible to restrain the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
The first rotation speed may be 0 rotations.
With such a configuration, it is possible to restrain the motor rotation speed from suddenly increasing from a state where the motor does not rotate, thus restraining the body from suddenly moving or the work device from suddenly working.
The motor restraining control may be a control to restrain the motor rotation speed from increasing.
In such a configuration, an increase of the output from the motor is restricted more easily and appropriately. Accordingly, it is possible to restrain the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
The motor restraining control may be a control to set an upper limit allowable for the motor rotation speed to a predetermined idling rotation speed larger than 0 rotations.
In such a configuration, the upper limit of the motor rotation speed is restricted to the idling rotation speed at which the travel device and the work device barely work, so that an increase in the motor rotation speed is restrained. Accordingly, it is possible to restrain the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
In addition, the rotation speed of the motor increases moderately, and this allows an operator to recognize, by a motor sound, that the motor is in operation. Accordingly, the operator can intentionally operate the shift operation tool and the accelerator operation tool in an appropriate procedure, so that travel or work can be started appropriately.
The motor restraining control may be a control to set the motor rotation speed to a predetermined second rotation speed larger than the first rotation speed, in response to the at least one shift operation tool being operated with the motor rotation speed being equal to or less than the first rotation speed.
In such a configuration, the motor rotation speed is set to the second rotation speed, so that the motor rotation speed is raised in advance. Accordingly, even when the accelerator operation tool is operated, it is possible to restrain the motor rotation speed from increasing rapidly. As a result, it is possible to restrain the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
Since the rotation speed of the motor increases moderately, the operator can recognize, by motor sound, that the motor is in operation. Accordingly, the operator can intentionally operate the shift operation tool and the accelerator operation tool in an appropriate procedure, so that travel or work can be started appropriately.
The motor restraining control may be a control to raise the motor rotation speed at a predetermined acceleration or less.
In such a configuration, a sudden increase in the output from the motor is restrained, and the output from the motor increases moderately. Accordingly, it is possible to restrain the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
The motor controller may be configured or programmed to stop the motor restraining control in response to the shift operation tool being restored.
When the shift operation tool is restored to a neutral position, for example, the travel device and the work device do not work. Accordingly, even when the motor restraining control is stopped, the body does not suddenly move or the work device does not suddenly work. When the shift operation tool and the accelerator operation tool are operated in an appropriate procedure in this state, travel or work can be started appropriately.
The motor controller may be configured or programmed to stop the motor restraining control in response to the shift operation tool being restored and the motor rotation speed becoming 0 rotations.
When the shift operation tool is restored to the neutral position, for example, and the motor rotation speed becomes 0 rotations, the travel device and the work device do not work. Accordingly, even when the motor restraining control is stopped, the body does not suddenly move or the work device does not suddenly work. When the shift operation tool and the accelerator operation tool are operated in an appropriate procedure in this state, travel or work can be started appropriately.
An electric work vehicle according to an example embodiment of the present invention includes a motor to drive at least either a travel device or a work device, at least one shift operation tool to shift a rotational power to drive the travel device or the work device, an accelerator operation tool to raise and lower a motor rotation speed of the motor, and a motor controller configured or programmed to control the motor rotation speed in response to an operation on the accelerator operation tool, and the electric work vehicle is configured to perform predetermined notification while the motor is in operation.
At the time when a body is to be moved, when the motor is wrongly recognized to be stopped though the motor works at a low rotation speed, and the shift operation tool and the accelerator operation tool are operated in an inappropriate procedure, the body might suddenly move unintentionally due to an increase in the motor rotation speed. In the meantime, at the time when a work device is to be operated, when the motor is wrongly recognized to be stopped though the motor works at a low rotation speed, and the shift operation tool and the accelerator operation tool are operated in an inappropriate procedure, the work device might suddenly work unintentionally due to an increase in the motor rotation speed.
In the above configuration, the predetermined notification is performed while the motor is in operation. This allows an operator to recognize that the motor is in operation. This restrains the motor from being wrongly recognized to be stopped though the motor works at a low rotation speed, and the operator can intentionally operate the shift operation tool and the accelerator operation tool in an appropriate procedure. As a result, travel or work can be started appropriately.
The notification may be performed while the motor rotation speed is 0 rotations or equal to or less than a predetermined first rotation speed after the at least one shift operation tool is operated.
When the shift operation tool is operated after the accelerator operation tool moderately raises the motor rotation speed, an increasing speed of the rotational power is relieved moderately by a power transmission mechanism to transmit power from the motor to the travel device or the work device.
Accordingly, the notification is performed in a case where the motor rotation speed is 0 rotations or the motor barely rotates after the shift operation tool is operated, and thus, the operator can recognize that the motor M is in operation. As a result, the operator can intentionally operate the shift operation tool and the accelerator operation tool in an appropriate procedure, so that travel or work can be started appropriately.
The motor controller may be configured or programmed to set the motor rotation speed to be equal to or less than a predetermined second rotation speed larger than the first rotation speed, in response to the at least one shift operation tool being operated with the motor rotation speed being equal to or less than the first rotation speed, and the notification may be performed by a rotary sound of the motor.
In such a configuration, the motor rotation speed is set to the second rotation speed, so that the motor generates motor sound. Thus, the operator can recognize, by the motor sound, that the motor is in operation. Accordingly, the operator can intentionally operate the shift operation tool and the accelerator operation tool in an appropriate procedure, so that travel or work can be started appropriately.
The motor controller may be configured or programmed to control the motor rotation speed not to become larger than an idling rotation speed that is a predetermined rotation speed larger than 0 rounds while the motor is in operation, and the notification may be performed by rotary sound of the motor.
In such a configuration, the motor rotation speed is set equal to or less than the idling rotation speed at which the travel device and the work device barely work, so that motor sound is generated from the motor. Thus, the operator can recognize, by a motor sound, that the motor is in operation. Accordingly, the operator can intentionally operate the shift operation tool and the accelerator operation tool in an appropriate procedure, so that travel or work can be started appropriately.
The electric work vehicle may further include a notifier to perform the notification.
With such a configuration, the operator can recognize that the motor is in operation. Accordingly, the operator can intentionally operate the shift operation tool and the accelerator operation tool in an appropriate procedure, so that travel or work can be started appropriately.
The notifier may be a speaker to emit a beep sound, and the notification may be performed by the beep sound.
With such a configuration, the operator can recognize, by the beep sound, that the motor is in operation. Accordingly, the operator can intentionally operate the shift operation tool and the accelerator operation tool in an appropriate procedure, so that travel or work can be started appropriately.
The notifier may be an alarm lamp, and the notification may be performed by lighting or flashing the alarm lamp.
With such a configuration, the operator can recognize, by the lighting or flashing of the alarm lamp, that the motor is in operation. Accordingly, the operator can intentionally operate the shift operation tool and the accelerator operation tool in an appropriate procedure, so that travel or work can be started appropriately.
The electric work vehicle may further include a hydrostatic continuously variable transmission to shift the rotational power to be transmitted from the motor to the travel device, and the at least one shift operation tool may include an HST operation tool to operate an angle of a cam plate of the hydrostatic continuously variable transmission.
With such a configuration, even in a case where the angle of the cam plate of the hydrostatic continuously variable transmission is not operated in an appropriate procedure, it is possible to restrain the body from suddenly moving and to cause the body to start traveling appropriately.
In a case where the HST operation tool to operate the angle of the cam plate of the hydrostatic continuously variable transmission is not operated in an appropriate procedure, the operator can recognize that the motor is in operation. Accordingly, the operator can intentionally operate the shift operation tool in an appropriate procedure, so that the body can start traveling appropriately.
The at least one shift operation tool may include a PTO operation tool to shift the rotational power to be transmitted from the motor to the work device.
With such a configuration, even in a case where the rotational power is not shifted in an appropriate procedure, it is possible to restrain the work device from suddenly working, so that the work device can start working appropriately.
In addition, in a case where the PTO operation tool to shift the rotational power is not operated in an appropriate procedure, the operator can recognize that the motor is in operation. Accordingly, the operator can intentionally operate the shift operation tool in an appropriate procedure, so that the work vehicle can start working appropriately.
The above and other elements, features, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of the example embodiments with reference to the attached drawings.
Example embodiments of the present invention will be described with reference to the drawings. Note that, in the following description, a direction of an arrow “F” in the drawings indicates “forward,” a direction of an arrow “B” indicates “rearward,” a direction of an arrow “L” indicates “left,” and a direction of an arrow R indicates “right,” unless otherwise specified. Further, in the drawings, a direction of an arrow “U” indicates “upward,” and a direction of an arrow “D” indicates “downward.”
The following describes an electric tractor (hereinafter just referred to as a “tractor”) as an electric work vehicle according to the present example embodiment. As illustrated in
The tractor also includes a body frame 2 and a driving section 3. The body frame 2 is supported on the right and left front wheels 10 (corresponding to a “travel device”) and the right and left rear wheels 11 (corresponding to a “travel device”).
The cover 12 is disposed in a front portion of a body. The driving section 3 is provided rearward of the cover 12. In other words, the cover 12 is disposed forward of the driving section 3.
The driving section 3 includes a protection frame 30, a driver seat 31, and a steering wheel 32. An operator can be seated on the driver seat 31. This allows the operator to get in the driving section 3. The right and left front wheels 10 are steered by an operation on the steering wheel 32. The operator can perform various driving operations in the driving section 3.
The tractor includes a drive battery 4. The cover 12 is swingable around an opening-closing axis Q along the left-right direction of the body. Thus, the cover 12 is openable and closable. When the cover 12 is closed, the drive battery 4 is covered with the cover 12.
As illustrated in
As illustrated in
The hydraulic pump 15a is driven by a rotational power from the motor M. When the hydraulic pump 15a is driven, a rotational power is output from the hydraulic motor 15b. Note that the hydrostatic continuously variable transmission 15 is configured to shift the rotational power between the hydraulic pump 15a and the hydraulic motor 15b. The hydrostatic continuously variable transmission 15 is also configured to continuously vary a gear ratio.
The rotational power output from the hydraulic motor 15b is transmitted to the transmission 16. The rotational power transmitted to the transmission 16 is shifted by a gear transmission mechanism of the transmission 16 and distributed to the right and left front wheels 10 and the right and left rear wheels 11. Thus, the right and left front wheels 10 and the right and left rear wheels 11 are driven.
As illustrated in
When a work device is connected to the mid PTO shaft 17 or the rear PTO shaft 18, the work device is driven by the rotational power from the mid PTO shaft 17 or the rear PTO shaft 18. For example, as illustrated in
As illustrated in
The main shift lever 34 and the auxiliary shift lever 35 are provided on a left side of the driver seat 31 and are used for an operation to set a vehicle travel speed in forward movement and reverse movement. The accelerator lever 37 is provided on a right side of the steering wheel 32 and is used to operate raising and lowering of a rotation speed of the motor M. The PTO lever 39 is provided on the left side of the driver seat 31 and is used to shift the rotational power of the PTO shaft.
The HST pedal 38 is provided on a right front side of the driver seat 31, on the floor of the driving section 3. The HST pedal 38 is operated by the right foot of an operator seated on the driver seat 31 and is used to start forward movement and reverse movement and to adjust the vehicle travel speed. The vehicle travel speed in this case is limited within a vehicle travel speed set by the main shift lever 34 and the auxiliary shift lever 35. When the HST pedal 38 receives a shifting operation on a rotational power to drive the wheels (the front wheels 10 and the rear wheels 11), and the HST pedal 38 is tilted forward from a neutral position, the angle of a cam plate of the hydrostatic continuously variable transmission 15 is changed, so that the body advances. When the HST pedal 38 is tilted rearward from the neutral position, the angle of the cam plate of the hydrostatic continuously variable transmission 15 is changed, so that the body reverses. The HST pedal 38 can operate the vehicle travel speed depending on the amount of forward or rearward tilting.
At the time when the body travels, the main shift lever 34 and the auxiliary shift lever 35 are first operated with the motor M being in operation, so as to set a highest vehicle speed in forward movement or reverse movement. Subsequently, the accelerator lever 37 is operated such that the rotation speed of the motor M is adjusted to a rotation speed suitable for travel and work. Then, the HST pedal 38 is operated, so that the body starts to travel. When the body is operated in such a procedure, the hydrostatic continuously variable transmission 15 restrains the rotational power of the motor M from being suddenly transmitted to the wheels (the front wheels 10 and the rear wheels 11), thus retraining the body from suddenly moving.
In a case where the power of the PTO shaft is adjusted at this time, the PTO lever 39 is operated after the accelerator lever 37 is operated to adjust the rotation speed of the motor M, so that a rotational power suitable for work is output to the PTO shaft. When the body is operated in such a procedure, the hydrostatic continuously variable transmission 15 restrains the rotational power of the motor M from being suddenly transmitted to a work device, thus retraining the work device from suddenly working.
Here, in a case where the operator does not notice the motor M working, and the operation tools are not operated in the appropriate procedure as described above, the body may not be able to start to travel appropriately, or the work device may not be able to work appropriately. For example, when the accelerator lever 37 is operated after the HST pedal 38 is operated, the rotational power of the motor M is suddenly (directly) transmitted to the wheels (the front wheels 10 and the rear wheels 11), so that the body might suddenly move unintentionally. In the meantime, when the accelerator lever 37 is operated after the PTO lever 39 is operated, the rotational power of the motor M is suddenly (directly) transmitted to the work device, so that the work device might suddenly work unintentionally.
The following will describe example embodiments to restrain such an inappropriate travel and work.
First described is a configuration to restrain inappropriate travel and work by controlling an output from the motor M based on
The tractor according to Example Embodiment 1 performs a predetermined motor restraining control so as to restrain inappropriate travel and work. The controller 50 is configured or programmed to control the motor restraining control. The controller 50 may include a processor such as a CPU or an ECU and works in response to a control performed by the processor.
The controller 50 is connected to operation tools such as the main shift lever 34, the auxiliary shift lever 35, the accelerator lever 37, the HST pedal 38, and the PTO lever 39 and controls the motor M, the hydrostatic continuously variable transmission 15, and the transmission 16 based on respective operation states of these operation tools. The motor M drives the wheels (the front wheels 10 and the rear wheels 11) and the PTO shafts (the mid PTO shaft 17 and the rear PTO shaft 18), as described above. The controller 50 may be connected to a notifier 26, and in this case, the controller 50 causes the notifier 26 to perform predetermined notification.
The controller 50 is configured or programmed to include an operation acquirer 52 and a motor controller 54. In a case where the notifier 26 is provided, the controller 50 further includes a notification controller 55.
The operation acquirer 52 acquires information on operations performed on the operation tools such as the main shift lever 34, the auxiliary shift lever 35, the accelerator lever 37, the HST pedal 38, and the PTO lever 39. More specifically, the operation acquirer 52 acquires information on operation positions of the operation tools, or the like.
The motor controller 54 is configured or programmed to control an output from the motor M such as a motor rotation speed or a torque of the motor M, based on the information on the operations performed on the operation tools which information is acquired by the operation acquirer 52. In a case where the accelerator operation tool, the HST pedal 38, and the PTO lever 39 are operated in an inappropriate procedure, the motor controller 54 performs a control to restrict an increase in the output of the motor M as the predetermined motor restraining control. The notification controller 55 is configured or programmed to cause the notifier 26 to perform predetermined notification and notifies that the motor restraining control is performed, for example.
In such a configuration, at the time when work travel is started with the motor M being in operation, the main shift lever 34 and the auxiliary shift lever 35 are operated first. Subsequently, the accelerator lever 37 (the accelerator operation tool) is operated such that the motor rotation speed of the motor M is adjusted. As an appropriate procedure, the accelerator lever 37 (the accelerator operation tool) is operated, and after that, the HST pedal 38 and the PTO lever 39 (the shift operation tools) are operated to respective positions suitable for work travel.
The following describes a step of performing the motor restraining control in a case where the operation tools are not operated appropriately. First, the accelerator lever 37 (the accelerator operation tool) is not operated, and the HST pedal 38 and the PTO lever 39 (the shift operation tools) are operated to respective positions suitable for work travel (step #1 in
Then, the motor controller 54 determines whether or not the motor rotation speed is 0 rotations (0 rotations/m (rpm)) (step #2 in
In a case where the accelerator lever 37 (the accelerator operation tool) is operated after the HST pedal 38 and the PTO lever 39 (the shift operation tools) are operated (Yes in step #3 in
In contrast, in a case where the motor restraining control is performed, even when the accelerator lever 37 is operated as indicated by a rotation speed transition LC1, the motor rotation speed is maintained at 0 rotations and does not change.
Thus, due to the motor restraining control in the present example embodiment, even when the accelerator lever 37 is operated, the motor rotation speed does not increase, so that the body does not move and the work device also does not work. This consequently restrains the body from suddenly moving or the work device from suddenly working, thus promoting the operation tools to be operated in an appropriate procedure. When the operation is restarted in an appropriate procedure, travel or work can be started appropriately.
When a predetermined stop condition is satisfied while the motor restraining control is being performed (step #5 in
When the stop condition to end the motor restraining control is provided, the tractor is restored to a state where the tractor can receive an operation to cause the body to travel or to cause the work device to work, and when the operations are performed in an appropriate procedure after that, travel or work can be started appropriately.
After the motor restraining control is ended or in a case where the motor rotation speed is not 0 rotations (0 rotations/m (rpm)) (No in step #2 in
The rotation speed of the motor M at the time when the motor retraining control is performed is not limited to 0 rotations, and the motor restraining control may be performed in a case where the operation tools are operated in a predetermined (inappropriate) procedure with the rotation speed of the motor M being equal to or less than a predetermined first rotation speed. The motor restraining control may be also performed in a case where it is not checked whether or not the rotation speed of the motor M is equal to or less than the predetermined first rotation speed or 0 rotations, and the accelerator lever 37 (the accelerator operation tool) is operated after the HST pedal 38 and the PTO lever 39 (the shift operation tools) are operated.
Thus, the motor restraining control is performed appropriately in a situation that requires the motor restraining control. This consequently restrains the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
The motor restraining control is not limited to restraining an increase in the motor rotation speed and may be a control to restrain an increase in the torque of the motor M. The motor restraining control is not limited to a control on the motor rotation speed or the torque of the motor M and may be an output restriction control to restrict an increase in the output from the motor M by a given method.
With such a configuration, it is possible to restrict (restrain) an increase in the rotational power of the motor M to be transmitted to the wheels (the front wheels 10 or the rear wheels 11) or the work device appropriately depending on the situation. This consequently restrains the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
The motor restraining control is not limited to restraining an increase in the motor rotation speed, and the motor restraining control may control the motor rotation speed not to become larger than a predetermined idling rotation speed larger than 0 rotations even when the accelerator lever 37 is operated. That is, as indicated by a rotation speed transition LC2 in
Thus, even when the accelerator lever 37 is operated, the motor rotation speed does not become larger than the idling rotation speed. This consequently restrains the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately. Besides, when the motor M reaches the idling rotation speed, the operator can notice, by rotary sound of the motor M, that the motor M is in operation. This allows the operator to recognize that the motor M is in operation and to intentionally move the body or operate the work device in an appropriate procedure. This consequently allows the operations to be performed in an appropriate procedure and restrains the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
The motor restraining control is not limited to restraining an increase in the motor rotation speed, and when the accelerator lever 37 is not operated, the motor restraining control may control the motor rotation speed to a predetermined rotation speed in a motor rotation speed range in which the body does not suddenly move or the work device does not suddenly work. For example, the motor restraining control may be performed such that, when the accelerator lever 37 is not operated, the motor rotation speed is set to a predetermined second rotation speed larger than the first rotation speed, and when the accelerator lever 37 is operated, the motor rotation speed may be raised from the second rotation speed in response to the manipulated variable of the accelerator lever 37. The second rotation speed is a motor rotation speed at which the body does not move and the work device cannot work, or a motor rotation speed at which the body travels only at a very low speed and the work device barely works. More specifically, the second rotation speed is 300 rotations/m (rpm) or more but 900 rotations/m (rpm) or less and is, for example, 600 rotations/m (600 rpm) that is slightly lower than a motor rotation speed at which the body substantially starts traveling. That is, as indicated by a rotation speed transition LC3 in
Thus, the motor rotation speed is raised in advance with the HST pedal 38 or the PTO lever 39 (shift operation tool) being operated, and therefore, even when the accelerator lever 37 (the accelerator operation tool) is operated, it is possible to restrain the motor rotation speed from increasing rapidly. This consequently restrains the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately. When the motor M maintains the second rotation speed, the operator can notice, by rotary sound of the motor M, that the motor M is in operation. This allows the operator to recognize that the motor M is in operation and to intentionally move the body or operate the work device in an appropriate procedure. This consequently restrains the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
The motor restraining control may be performed to raise the motor rotation speed at a predetermined acceleration or less. That is, in a case where the accelerator lever 37 (the accelerator operation tool) is operated after the HST pedal 38 or the PTO lever 39 (the shift operation tool) is operated, the motor restraining control is performed to moderately raise the motor rotation speed at the predetermined acceleration or less. This consequently restrains the motor rotation speed from suddenly increasing and also restrains the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
The tractor may not include the notifier 26. Thus, the tractor can be achieved with a simpler configuration.
Next will be described, as Example Embodiment 2, a configuration in which, when the motor M is in operation, inappropriate travel and work is restrained by notifying that the motor M is in operation, based on
In order to restrain inappropriate travel and work, a tractor according to Example Embodiment 2 notifies that the motor M is in operation, while the motor M is in operation. Due to this notification, the operator recognizes that the motor M is in operation, so that the operator can intentionally cause the body to travel or the work device to work in an appropriate procedure. This consequently allows the operations to be performed in an appropriate procedure and restrains the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
At the time when the tractor according to Example Embodiment 2 starts work travel with the motor M being in operation, the main shift lever 34 and the auxiliary shift lever 35 are operated first. Then, the accelerator lever 37 (the accelerator operation tool) is operated such that the motor rotation speed of the motor M is adjusted. As an appropriate procedure, after the accelerator lever 37 (the accelerator operation tool) is operated, at least either the HST pedal 38 or the PTO lever 39 (the shift operation tool) is operated to a position suitable for work travel.
The following describes a control performed by the tractor in a case where the operations are performed in an inappropriate procedure. First, the accelerator lever 37 (the accelerator operation tool) is not operated, and the HST pedal 38 and the PTO lever 39 (the shift operation tools) are operated to respective positions suitable for work travel (step #1 in
Then, the motor controller 54 determines whether or not the motor rotation speed is 0 rotations (0 rotations/m (rpm)) (step #2 in
In a case where the motor rotation speed is 0 rotations (Yes in step #2 in
Then, the operator who recognizes that the motor M is in operation changes the HST pedal 38 and the PTO lever 39 (the shift operation tools) to an OFF state (a neutral state) and operates the accelerator lever 37 (the accelerator operation tool), and after that, the operator operates at least either the HST pedal 38 or the PTO lever 39 (the shift operation tools) (step #4 in
In such a configuration, the operator recognizes that the motor M is in operation, so that the operator can intentionally cause the body to travel or operate the work device in an appropriate procedure. This consequently allows the operations to be performed in an appropriate procedure and restrains the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
The notification to notify that the motor M is in operation may be performed in a case where the rotation speed of the motor M is equal to or less than the predetermined first rotation speed after at least either the HST pedal 38 or the PTO lever 39 (the shift operation tool) is operated, as well as the case where the rotation speed of the motor M is 0 rotations.
Thus, the notification is performed appropriately in a state where the operator should recognize that the motor M is in operation, so that the operator can accurately recognize that the motor M is in operation. As a result, the operator performs the operation in an appropriate procedure, thus restraining the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
The notification is performed not only in a case where the motor rotation speed is not limited to 0 rotations (equal to or less than the first rotation speed) at the time when at least either the HST pedal 38 or the PTO lever 39 is operated. While the motor rotation speed is 0 rotations or equal to or less than the first rotation speed after the motor M is started, the notification controller 55 may cause the notifier 26 to notify that the motor M is in operation. In this case, the notification controller 55 may end the notification in response to the accelerator lever 37 (the accelerator operation tool) being operated.
This more accurately restrains at least either the HST pedal 38 or the PTO lever 39 (the shift operation tool) from being operated with the accelerator lever 37 (the accelerator operation tool) being not operated. As a result, the operator performs the operations in an appropriate procedure, thus restraining the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
Together with or separately from with each of the above example embodiments, the tractor may maintain the motor rotation speed to be equal to or more than an idling rotation speed that is a predetermined rotation speed at least larger than 0 rotations while the motor M is in operation (LC4 in
At the time when the motor restraining control in Example Embodiment 1 is performed, the notification controller 55 may cause the notifier 26 to notify at least either that the motor restraining control is to be performed or that the motor M is in operation. This allows the operator to more accurately recognize that the motor M is in operation. As a result, the operator performs the operations in an appropriate procedure, thus restraining the body from suddenly moving or the work device from suddenly working, so that travel or work can be started appropriately.
In each of the above example embodiments, the shift operation tool is not limited to the HST pedal 38 and the PTO lever 39 and may be a given operation tool to shift the rotational power or may be a given combination of given operation tools. The accelerator operation tool is not limited to the accelerator lever 37 and may be a given operation tool to raise and lower the motor rotation speed of the motor M or may be a given combination of given operation tools. At the time when at least one shift operation tool and at least one accelerator operation tool are operated in an inappropriate procedure, at least either the motor restraining control or predetermined notification is performed.
Thus, at least either the motor restraining control or the predetermined notification can be performed depending on the configuration of the tractor, and travel or work can be started appropriately.
In each of the above example embodiments, a given notifier can be used as the notifier 26, provided that the notifier is configured to perform notification to the operator. For example, the notifier 26 may include a speaker or a voice alarm generator that can generate voice or beep sound, an LED, a lamp, or an alarm lamp that can perform notification via a lighting or flashing pattern, a monitor or an information terminal that can display a character or an image, or the like, or a combination thereof. Thus, the notification easily noticed by the operator can be performed depending on the situation.
In each of the above example embodiments, the travel device is not limited to a wheel and may be a crawler.
In each of the above example embodiments, the controller 50 is not limited to being configured or programmed to include the aforementioned functional blocks but may be configured or programmed to include given functional blocks. For example, each of the function blocks of the controller 50 may be further subdivided, or some or all of the function blocks may be integrated. The functions of the controller 50 are not limited to the above functional blocks and may be implemented by a method performed by a given functional block. Some or all of the functions of the controller 50 may be software. A program for the software is stored in a given storage device and is executed by a processor such as the CPU included in the controller 50 or a processor provided separately.
Example embodiments of the present invention are applicable to electrically-driven farm work vehicles such as a harvester and a rice transplanter, including a tractor, and various electric work vehicles that are electrically driven to travel and perform various works.
While example embodiments of the present invention have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the present invention. The scope of the present invention, therefore, is to be determined solely by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-074715 | Apr 2022 | JP | national |
| 2022-074716 | Apr 2022 | JP | national |
This application claims the benefit of priority to Japanese Patent Application No. 2022-074715 and 2022-074716 filed on Apr. 28, 2022 and is a Continuation Application of PCT Application No. PCT/JP2023/003484 filed on Feb. 3, 2023. The entire contents of each application are hereby incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2023/003484 | Feb 2023 | WO |
| Child | 18916889 | US |
