This application claims priority to Japanese Patent Application No. 2022-181172 filed Nov. 11, 2022, the disclosure of which is hereby incorporated by reference in its entirety.
The present invention relates to an electric work vehicle.
In such a conventional work vehicle disclosed in Japanese Patent Publication JP2019-060426A as an example, an operator changes a shift level of a transmission while operating an operation tool as a means of varying a speed of a motive power inputted from an engine. In the conventional work vehicles, the operator can change not only the shift level but also a direction of travel to either a front direction or a reverse direction by operating the operation tool. In recent years, an electric motor has been increasingly employed in the work vehicle as a driving source instead of an engine. The electric motor is able to rotate in both a forward direction and a reverse direction. On the other hand, the conventional operation tool is merely configured to operate the transmission. That is, in a case that the conventional operation tool is employed in a work vehicle driven by the electric motor, an additional operation tool is necessary for changing the direction of a rotation of the electric motor. The present invention provides an electric work vehicle which simplifies an operation for changing the direction of the rotation of the electric motor.
An electric work vehicle including:
According to this configuration, an operator can change not only the shift level of the transmission but also the direction of the rotation of the electric motor by operating the single operation part. That is, the operator can switch a travel direction of the electric work vehicle between a forward travel and a reverse travel without an additional operation tool for changing the direction of the rotation of the electric motor. Therefore, an operation for changing the direction of the rotation of the electric motor is simplified in the electric work vehicle.
In one preferred embodiment of the electric work vehicle of the present invention,
According to this configuration, the operator can change the shift level by operating the lever in the front-back direction and can switch the travel direction of the electric work vehicle between the forward travel and the reverse travel by operating the lever in the left-right direction. This enables the operator to operate the lever intuitively.
In one preferred embodiment of the electric work vehicle of the present invention,
According to this configuration, the lever moves along the first hole when the operator operates the lever in the front-back direction. In addition, the lever moves along the second hole when the operator operates the lever in the left-right direction. This enables the operator to operate the lever in respective front, back, left and right directions certainly. That is, this configuration can avoid a risk of unintentional switching between the forward travel and the reverse travel and a risk of unintentional change of the shift level, which would otherwise be caused by slipping operator's hand.
In one preferred embodiment of the electric work vehicle of the present invention,
This configuration enables the operator to cause the electric work vehicle traveling forward by operating the lever forward or backward from the neutral position and to cause the electric work vehicle traveling backward by operating the lever leftward or rightward from the neutral position. The electric work vehicle stops in a case of the lever positioned at the neutral position. That is, the operator can cause the electric work vehicle traveling forward or backward by operating the lever forward, backward, leftward and rightward from the neutral position as a start point.
In one preferred embodiment of the electric work vehicle of the present invention,
According to this configuration, the lever is returned to the neutral position by the biasing mechanism when the operator is putting the lever back to the neutral position. Therefore, in comparison with a configuration without the biasing mechanism, the operator does not need to adjust a position of the lever when the operator is putting the lever back to the neutral position, thus relieving a burden of the operator.
In one preferred embodiment of the electric work vehicle of the present invention,
This configuration switches the travel direction of the electric work vehicle from the forward travel to the reverse travel when the operator operates the lever leftward or rightward from the longitudinal intermediate portion of the first hole. This enables the operator to operate the lever intuitively.
In one preferred embodiment of the electric work vehicle of the present invention,
This configuration allows the lever to move, along the second hole, to only one side, the
left side or the right side, of the of the first hole. This switches the travel direction of the electric work vehicle from the forward travel to the reverse travel when the operator operates the lever leftward or rightward along the second hole from the first hole. This enables the operator to operate the lever intuitively.
In one preferred embodiment of the electric work vehicle of the present invention,
According to this configuration, the lever is guided to the third hole when the operator operates the lever leftward or rightward from the first hole. Furthermore, the shift level in a case of the work vehicle traveling backward is changed when the operator operates the lever in the front-back direction along the third hole. That is, first, the travel direction of the electric work vehicle is switched from the forward travel to the reverse travel when the operator operates the lever in the left-right direction along the second hole, and then, the shift level is changed when the operator operates the lever in the front-back direction. This enables the operator to operate the lever intuitively.
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 preferred embodiments with reference to the attached drawings.
Throughout embodiments, unless otherwise noted, “front” is defined as a front side corresponding to a front-back direction (traveling direction) relative to a body of the electric work vehicle, “back” is defined as a back side corresponding to the front-back direction relative to the body of the electric work vehicle, a left-right direction or a lateral direction is defined as a traversing direction (width direction) perpendicular to the front-back direction relative to the body of the electric work vehicle, “top” and “bottom” refer to positional relationship based on a ground height in a vertical direction relative to the body of the electric work vehicle.
Modes for carrying out the present invention will be described with reference to the drawings showing a utility vehicle as an example of an electric work vehicle. An example of the utility vehicle shown in
The illustrated utility vehicle includes a pair of left and right drivable and steerable front wheels 11 and a pair of left and right drivable rear wheels 12. A travel body 1 is able to travel by the pair of front wheels 11 and the pair of rear wheels 12. The travel body 1 includes a driver's section 13 in a center portion thereof which driver's section 13 an operator boards to perform an operation. The travel body 1 includes a loading platform 14 in a rear portion thereof on which luggage is loadable. The travel body 1 is mounted with a motive power unit 2 located in an area below the loading platform 14. The motive power unit 2 includes a rotationally drivable electric motor 2m as a chief element.
The travel body 1 is mounted with a powertrain device 20. The powertrain device 20 transmits a motive power inputted from the motive power unit 2 to the pair of front wheels 11 and the pair of rear wheels 12. In this way, the pair of front wheels 11 and the pair of rear wheels 12 move on a ground based on a rotational drive of the electric motor 2m. The pair of front wheels 11 and the pair of rear wheels 12 correspond to a “travel device” recited in the claims.
The driver's section 13 is surrounded and protected by a ROPs frame 15 in a boxed shape. The driver's section 13 includes a driver's seat 16 on which an operator sits. In front of the driver's seat 16, the driver's section 13 includes a front panel 3 in which various operation tools and display devices are assembled, and a steering handle 17 for steering the pair of front wheels 11. The driver's section 13 includes an acceleration pedal 18 in a floor area thereof below the steering handle 17.
The powertrain device 20 to which the motive power from the motive power unit 2 is input includes a gear transmission mechanism 21, a rear wheel differential mechanism 22, a front wheel differential mechanism 23, and the like. The gear transmission mechanism 21 in this embodiment includes a transmission 24. The transmission 24 is configured to switch a shift level between a high-speed stage and a low-speed stage by a high-low shift clutch. That is, the transmission 24 is configured to transmit the motive power from the electric motor 2m to the pair of front wheels 11 and the pair of rear wheels 12 (i.e., the travel device) while varying the speed of the rotation inputted from the electric motor 2m.
To the front panel 3, there are assembled: a meter panel 30 which has a liquid-crystal display (LCD) and light-emitting diode (LED) lamp; a single shift operation part 31; a speed limit operation tool 34; and the like. The shift operation part 31 accepts a manual operation for changing the shift level of the transmission 24. The shift operation part 31 includes a single shift lever 32, a shift gate 33. The shift operation part 31 is provided with a biasing mechanism 32a. Alternatively, the shift operation part 31 may include the biasing mechanism 32a. The shift gate 33 is formed in a H-shape in the front panel 3. The shift lever 32 is movable along the shift gate 33 with the H-shape. The shift lever 32 is operable in front, back, left and right directions. The biasing mechanism 32a biases the shift lever 32 to a neutral position described later. The biasing mechanism 32a may be a plate spring, a coil spring, a torsion spring or a rubber. The biasing mechanism 32a may also be a composite containing at least one of the spring and the rubber. The shift operation part 31 corresponds to a “single operation tool” recited in claims. The shift lever 32 corresponds to a “single lever” recited in claims.
The speed limit operation tool 34 sets an upper limit of a vehicle speed. The speed limit operation tool 34 is a circular dial tool. An arc-shaped upper speed limit indicator 36 is provided around the speed limit operation tool 34. The upper speed limit indicator 36 has an arc-shaped scale indicative of the vehicle speed. The upper speed limit indicator 36 is provided with a pointer 37 which is disposed below the arc-shaped scale and mechanically linked to the speed limit operation tool 34.
As shown in
A travel battery device 42 is, for example, a lithium-ion battery. Not shown in diagrams, the travel battery device 42 is composed of a plurality of small low-voltage unit batteries (cells) stacked together. The travel battery device 42 outputs a voltage of, for example, 250 volts. The unit batteries (cells) are housed in a sealed storage case of the travel battery device 42. The controller 40 connects with the inverter 41 via a harness (not shown) for signals. The controller 40 outputs a control signal to the inverter 41 in response to an operation of the acceleration pedal 18. In response to the control signal by the controller 40, the inverter 41 adjusts an electric power (voltage, frequency and current) to be supplied to the electric motor 2m from the travel battery device 42 and controls an output of the electric motor 2m.
The controller 40 connects with the transmission 24 via a harness (not shown) for signals. The controller 40 outputs a control signal to the transmission 24 in response to an operation of the shift lever 32. The transmission 24 sets the shift level to either the high-speed stage or the low-speed stage in response to the control signal by the controller 40.
In this embodiment, the shift lever 32 functions as a forward/reverse switching lever which switches a travel direction of the electric work vehicle between a forward travel and a reverse travel. The shift gate 33 has a forward operation hole 33F for a forward operation, a reverse operation hole 33R for a reverse operation, and an intermediate hole 33M. The forward operation hole 33F and the reverse operation hole 33R are arranged side by side, and configured to guide the shift lever 32 in the front-back direction during the operation of the shift lever 32. The intermediate hole 33M is located between the forward operation hole 33F and the reverse operation hole 33R, and communicates with each of the forward operation hole 33F and the reverse operation hole 33R.
That is, the intermediate hole 33M intersects with each of the forward operation hole 33F and the reverse operation hole 33R. The intermediate hole 33M is configured to guide the shift lever 32 in the left-right direction during the operation of the shift lever 32. A right end portion (first end portion) of the intermediate hole 33M connects with the forward operation hole 33F. The reverse operation hole 33R intersects with a left end portion (second end portion), which is an opposite end portion of the right end portion, of the intermediate hole 33M and is configured to guide the shift lever 32 in the front-back direction during the operation of the shift lever 32. The forward operation hole 33F corresponds to a “first hole” recited in claims. The intermediate hole 33M corresponds to a “second hole” recited in claims. The reverse operation hole 33R corresponds to a “third hole” recited in claims.
The both ends of the forward operation hole 33F are respectively defined as a low-speed forward travel position 33a and a high-speed forward travel position 33b. The both ends of the reverse operation hole 33R are respectively defined as a low-speed reverse travel position 33c and a high-speed reverse travel position 33d. A middle position between the low-speed forward travel position 33a and the high-speed forward travel position 33b is a neutral position 33e. A middle position between the low-speed reverse travel position 33c and the high-speed reverse travel position 33d is a neutral position 33f. Both neutral positions 33e, 33f are connected by the intermediate hole 33M. In other words, the intermediate hole 33M intersects with the longitudinal intermediate portion of the forward operation hole 33F and the longitudinal intermediate portion of the reverse operation hole 33R.
In this embodiment, as shown in
In a case of the shift lever 32 positioned at the neutral position 33e or the neutral position 33f, the controller 40 prevents the electric motor 2m from driving even when the acceleration pedal 18 is operated. In this case, the inverter 41 supplies no electric power to the electric motor 2m. That is, the controller 40 is configured to transmit no motive power to the pair of front wheels 11 and the pair of rear wheels 12 (i.e., the travel device) in a case of the shift lever 32 positioned at the neutral positions 33e, 33f.
In a case of the shift lever 32 positioned at the low-speed forward travel position 33a or the high-speed forward travel position 33b, the controller 40 outputs to the inverter 41 the control signal for a forward rotation of the electric motor 2m, in response to the operation of the acceleration pedal 18. The inverter 41 controls the electric motor 2m to rotate the electric motor 2m in a forward direction in response to the control signal by the controller 40. That is, the controller 40 is configured to control the electric motor 2m to rotate in the direction which makes the pair of front wheels 11 and the pair of rear wheels 12 (i.e., the travel device) travel forward in a case of the shift lever 32 operated forward or backward along the forward operation hole 33F from the neutral position 33e. The controller 40 controls the electric motor 2m to rotate in the direction which makes the travel device travel forward in response to the operation of the acceleration pedal 18. Instead of the acceleration pedal 18, a tool for adjusting the speed of the rotation of the electric motor 2m may be employed on the electric work vehicle.
In a case of the shift lever 32 positioned at the low-speed reverse travel position 33c or the high-speed reverse travel position 33d, the controller 40 outputs to the inverter 41 the control signal for a reverse rotation of the electric motor 2m, in response to the operation of the acceleration pedal 18. The inverter 41 controls the electric motor 2m to rotate the electric motor 2m in a reverse direction in response to the control signal by the controller 40. Putting this configuration in other words, the controller 40 is configured to control the electric motor 2m to rotate in the direction which makes the pair of front wheels 11 and the pair of rear wheels 12 (i.e., the travel device) travel backward in a case of the shift lever 32 operated leftward along the intermediate hole 33M (not along the forward operation hole 33F) from the neutral position 33e. The controller 40 control the electric motor 2m to rotate in the direction which makes the travel device travel backward in response to the operation of the acceleration pedal 18.
That is, the controller 40 is configured to change the direction of the rotation of the electric motor 2m in response to the shift lever 32 operated in the left-right direction and to change the shift level of the transmission 24 in response to the shift lever 32 operated in the front-back direction. With this configuration in this embodiment, the powertrain device 20 does not have to include a reverse mechanism for switching the travel direction between the forward travel and the reverse travel. In other words, switching of the direction of the rotation of the electric motor 2m realizes switching between the forward travel and the reverse travel. In this way, the shift lever 32 is configured to accept the manual operation for changing the direction of the rotation of the electric motor 2m and for changing the shift level of the transmission 24. The controller 40 is configured to output the control signal to the electric motor 2m and the transmission 24 based on the manual operation accepted by the shift lever 32.
With the above-described configuration in this embodiment, it is possible to switch the direction of the rotation of the electric motor 2m and to change the shift level of the transmission 24 by the single shift operation part 31, i.e., by the single shift lever 32.
The present invention is not limited to the configuration illustrated in the above embodiment. Other representative embodiments of the invention will be described below.
(1) The reverse operation hole 33R shown in
(2) The electric work vehicle may include a shift gate 51 shown in
(3) The electric work vehicle may include a shift gate 52 shown in
(4) The electric work vehicle may include a shift gate 53 shown in
Note that the configuration disclosed in the above embodiments (including other embodiments; the same applies to the following) may be combined with configurations disclosed in other embodiments, as long as no contradiction arises. The embodiments disclosed herein are illustrative. Embodiments of the present invention are not limited thereto, and can be altered without departing from the object of the present invention.
The present invention is applicable to an electric work vehicle.
Number | Date | Country | Kind |
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2022-181172 | Nov 2022 | JP | national |