Work vehicle

Abstract

To effectively use a detection range of a potentiometer when detecting an operation position of an artificial operation tool is detected by a potentiometer in a work vehicle.SOLUTION: A work vehicle comprises: an artificial operation tool 12 that can swing around a first shaft core P1; and a potentiometer in which a free end of a detection arm 25b that can swing around a second shaft core P2 along the first shaft core P1 is connected to the artificial operation tool 12. Since the detection arm 25b is operated around the second shaft core P2 in conjunction with the artificial operation tool 12 operated around the first shaft core P1, the potentiometer detects an operation position of the artificial operation tool 12. In a first length L1 from the first shaft core P1 to a connection portion 21e between the free end of the detection arm 25b and the artificial operation tool 12 and a second length L2 from the second shaft core P2 to a connection portion 21e between the free end of the detection arm 25b and the artificial operation tool 12, the second length L2 is shorter than the first length L1.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a configuration for detecting the operating position of a manually operated tool in a work vehicle. [Background technology]

[0002] As disclosed in Patent Document 1, some work vehicles are provided with a manually operated gear shift lever (corresponding to a manually operated tool) and a potentiometer that detects the operation position of the gear shift lever. As a result, when a worker on the work vehicle operates the gear shift lever, the potentiometer detects the operating position of the gear shift lever, and the traveling transmission is operated based on the detection value of the potentiometer (operating position of the gear shift lever).

[0003] When the gear shift lever is capable of swinging about its axis, a potentiometer is provided at the axis of the gear shift lever and the gear shift lever is connected to the potentiometer, thereby allowing the potentiometer to detect the operation position of the gear shift lever. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-10436 A (see FIG. 2) Summary of the Invention [Problem to be solved by the invention]

[0005] When a potentiometer is provided at the axis position of the manual operating tool and the manual operating tool is connected to the potentiometer so that the operating position of the manual operating tool is detected by the potentiometer, the operating range of the manual operating tool is the range in which the potentiometer outputs a detection value.

[0006] The detection range of the potentiometer, which is the range within which the potentiometer can output a detection value, is often larger than the operating range of the manual operating tool, so even if the manual operating tool is operated from one end to the other end of the operating range of the manual operating tool, there will be a portion of the detection range of the potentiometer that is not used. This leaves room for improvement in terms of effectively using the detection range of the potentiometer.

[0007] SUMMARY OF THE PRESENT INVETION The present invention has an object to provide a configuration in which, when the operating position of a manual operating tool is detected by a potentiometer in a work vehicle, the detection range of the potentiometer can be effectively used. [Means for solving the problem]

[0008] The work vehicle of the present invention is equipped with a body having a driving section, right and left traveling devices provided on the body, an manual operating tool that is swingable around a first axis and operated manually, and a detection arm that can swing around a second axis along the first axis, the free end of the detection arm being connected to the manual operating tool, and a potentiometer, in which the detection arm is operated around the second axis in conjunction with the manual operating tool being operated around the first axis, thereby detecting the operating position of the manual operating tool by the potentiometer, and the first axis and the second axis are arranged at a position where a first length from the first axis to the connection part between the free end of the detection arm and the manual operating tool, and a second length from the second axis to the connection part between the free end of the detection arm and the manual operating tool are shorter than the first length.

[0009] According to the present invention, there is provided an manual operation tool that can be swung around a first axis, and a potentiometer having a detection arm that can be swung around a second axis, and the free end of the detection arm is connected to the manual operation tool. In conjunction with the operation of the manual operation tool around the first axis, the detection arm is operated around the second axis, and the operation position of the manual operation tool is detected by the potentiometer.

[0010] In the above-mentioned configuration, according to the present invention, the second length from the second axis to the connection portion between the free end of the detection arm and the manual operation tool is shorter than the first length from the first axis to the connection portion between the free end of the detection arm and the manual operation tool. As a result, the operation of the manual operating tool is magnified and transmitted to the detection arm, and the operation angle of the detection arm becomes larger than the operation angle of the manual operating tool, so that the unused portion of the detection range of the potentiometer can be reduced, and the detection range of the potentiometer can be used effectively.

[0011] According to the present invention, the operation of the manual operating tool is magnified and transmitted to the detection arm, and the operation angle of the detection arm becomes larger than the operation angle of the manual operating tool. Therefore, even if the operation of the manual operating tool is small, the operation of the manual operating tool can be detected with high accuracy by the potentiometer, thereby improving the detection accuracy of the operation position of the manual operating tool.

[0012] In the present invention, it is preferable that the second axis is arranged so that when the manual operating tool is located at the center position of the operating range of the manual operating tool, when viewed from the direction of the first axis, the second axis is located on a virtual line passing through the connection part between the free end of the detection arm and the manual operating tool and the first axis.

[0013] According to the present invention, when the manual operation tool is located at the center of the operation range of the manual operation tool, the detection arm is located at the center of the detection range of the detection arm. When the manual operating tool is operated to one side and the other from the central position of the operating range of the manual operating tool, the detection arm is operated to one side and the other from the central position of the detection range of the detection arm, and the operation of the detection arm is symmetrical with respect to the central position of the detection range of the detection arm.

[0014] As a result, if the operation of the detection arm is symmetrical with respect to the central position of the detection range of the detection arm, the operation of the detection arm is less likely to differ on one side and the other side of the central position of the detection range of the detection arm, which is advantageous in terms of improving the detection accuracy of the operating position of the manual operating tool.

[0015] In the present invention, it is preferable that the second axis is disposed closer to the first axis than a connection portion between the free end of the detection arm and the manual operation tool.

[0016] According to the present invention, the potentiometer and the detection arm are disposed close to the first axis of the manual operation tool in the longitudinal direction of the manual operation tool, so that the manual operation tool and the potentiometer can be disposed compactly.

[0017] In the present invention, it is preferable that the second axis is disposed within an operating range of the manual operation tool when viewed from a direction of the first axis.

[0018] According to the present invention, in addition to the potentiometer and detection arm being positioned close to the first axis of the manual operating tool in the longitudinal direction of the manual operating tool, the potentiometer and detection arm are also positioned close to the first axis of the manual operating tool in a direction perpendicular to the longitudinal direction of the manual operating tool, which is advantageous in terms of arranging the manual operating tool and potentiometer compactly.

[0019] In the present invention, it is preferable that right and left transmissions are provided for operating the right and left traveling devices, the right manual operating device is a right shift lever capable of operating the right transmission and is provided in the right part of the driving section, the left manual operating device is a left shift lever capable of operating the left transmission and is provided in the left part of the driving section, and the right transmission is operated based on the detection value of the right potentiometer and the left transmission is operated based on the detection value of the left potentiometer.

[0020] Some work vehicles are equipped with right and left transmissions that operate the right and left traveling gear independently, and are configured so that the right transmission is operated by the right transmission lever, which is a manually operated tool, and the left transmission is operated by the left transmission lever, which is also a manually operated tool. In this work vehicle, the right shift lever is provided on the right side of the driver's section, and the left shift lever is provided on the left side of the driver's section. An operator in the driver's section can hold and operate the right shift lever with his right hand, and can operate the left shift lever with his left hand.

[0021] According to the present invention, in a work vehicle equipped with right and left shift levers as described above, the operating positions of the right and left shift levers are appropriately detected by right and left potentiometers to operate the right and left transmissions.

[0022] In the present invention, it is preferable that the potentiometer is provided closer to the left and right center of the driving section than the gear shift lever.

[0023] According to the present invention, when the right and left shift levers are provided on the right and left parts of the driver's section, the right and left potentiometers are provided closer to the left and right center of the driver's section than the shift levers. This reduces the likelihood of the potentiometer coming into contact with obstacles at the work site, which is advantageous in terms of protecting the potentiometer and improving the durability of the potentiometer.

[0024] In the present invention, the speed change device can be operated to a neutral position, a forward side, and a reverse side, and the speed change lever has a base portion provided on the machine body so as to be swingable about the first axis along the left-right direction, and a lever portion having a handle portion to be held by an operator provided at an upper portion, attached to the base so as to be swingable about a third axis along a direction perpendicular to the first axis, and swingable integrally with the base about the first axis, and the potentiometer detects an operating position of the base, and when the speed change lever is in a neutral position within an operating range thereof, the potentiometer detects an operating position of the base, and detects a forward side and a reverse side. It is preferable that a lever guide is provided having a neutral guide portion capable of guiding the lever portion in a direction along the left-right direction, and forward and reverse side travel guide portions capable of guiding the lever portion in a front-rear direction in a range other than the neutral position of the operating range of the shift lever, and that when the lever portion is operated to the neutral position within the operating range of the shift lever and to the neutral guide portion, the shift device is operated to the neutral position, and when the lever portion is operated to the forward and reverse side travel guide portions, the shift device is operated to the forward and reverse sides.

[0025] In the above-mentioned work vehicle, the transmission is configured so that it can be operated to the neutral position, forward side, and reverse side. When the shift lever is operated to the forward side travel guide part of the lever guide, the transmission is operated to the forward side, and when the shift lever is operated to the reverse side travel guide part of the lever guide, the transmission is operated to the reverse side. When the shift lever is operated to the neutral position, the transmission is operated to the neutral position and stopped. In this case, the shift lever is held in the neutral position by being operated into the neutral guide portion of the lever guide, and the transmission is held in the neutral position.

[0026] As in the above-mentioned work vehicle, when the shift lever is operated in the forward / rearward direction (the forward and reverse travel guide portions of the lever guide) and the left / right direction (the neutral guide portion of the lever guide), according to the present invention, the shift lever has a base portion and a lever portion. The base is provided on the body so as to be swingable about a first axis along the left-right direction. The lever is attached to the base so as to be swingable about a third axis that is perpendicular to the first axis, and has a handle at its top for an operator to hold. The lever can swing integrally with the base around the first axis.

[0027] According to the present invention, the potentiometer detects the operating position of the base of the shift lever. When the shift lever is operated in the forward or backward direction (the forward and reverse travel guide portions of the lever guide), the potentiometer detects the operating position of the shift lever via the base of the shift lever. When the shift lever is operated to the neutral position, the potentiometer detects that the shift lever is in the neutral position via the base of the shift lever.

[0028] When the shift lever is operated to the neutral position and then operated into the neutral guide portion of the lever guide, the lever portion of the shift lever swings left and right relative to the base, so that the base of the shift lever does not move from the neutral position, and the potentiometer detects that the shift lever is in the neutral position via the base of the shift lever. This allows the potentiometer to easily detect the operating position of the shift lever in a configuration in which the shift lever is operated in the forward / backward direction (the forward and reverse travel guide portions of the lever guide) and the left / right direction (the neutral guide portion of the lever guide). [Brief description of the drawings]

[0029] [Figure 1] FIG. 2 is a left side view of the riding type grass mower. [Diagram 2] FIG. 2 is a plan view of the riding type grass mower. [Diagram 3] FIG. 4 is a plan view of the vicinity of the shift lever and the support case. [Figure 4] FIG. 4 is a cross-sectional plan view of the vicinity of the shift lever and the support case. [Diagram 5] FIG. 2 is a vertical sectional front view of the vicinity of the shift lever and the support case. [Figure 6] FIG. 4 is a vertical sectional right side view of the vicinity of the shift lever and the support case. [Figure 7]5 is a diagram showing the relationship between the operation range of a shift lever and the detection range of a potentiometer. FIG. [Figure 8] FIG. 11 is a diagram showing the relationship between the operation range of a shift lever and the detection range of a potentiometer in the first alternative embodiment of the invention. [Figure 9] FIG. 11 is a diagram showing the relationship between the operation range of a shift lever and the detection range of a potentiometer in a second alternative embodiment of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] Figures 1 to 9 show an electric riding grass mower, which is an example of a work vehicle, and in Figures 1 to 9, F indicates the forward direction, B indicates the rearward direction, U indicates the upward direction, D indicates the downward direction, R indicates the rightward direction, and L indicates the leftward direction.

[0031] (Overall configuration of riding grass mower) As shown in Figs. 1 and 2, the riding grass mower has a body 4, a front wheel 1, a rear wheel 2 (corresponding to a traveling device), a mower 5, a battery 6, a driving section 27, and the like.

[0032] Right and left body frames 3 are provided along the fore-and-aft direction, and a plurality of horizontal frames (not shown) along the left-right direction are connected across the right and left body frames 3 to form a body 4. Right and left front wheels 1 are provided at the front of the body 4, and right and left rear wheels 2 are provided at the rear of the body 4, with the front wheels 1 and rear wheels 2 supporting the body 4.

[0033] A mower 5 is attached between the front wheel 1 and the rear wheel 2 at the bottom of the machine body 4, and a battery 6 is attached between the right and left rear wheels 2 at the rear of the machine body 4, and a cover 7 is provided to cover the upper part of the battery 6. A driver's section 27 is provided on the machine body 4, and a driver's seat 8 and a rope frame 9 are provided on the driver's section 27.

[0034] (Front and rear wheel configuration) As shown in Figures 1 and 2, the right and left front wheels 1 are configured as caster wheels that can freely change direction around an axis that runs in the vertical direction, and are attached to the front of the right and left body frames 3.

[0035] Right and left rear wheel transmission cases 10 are connected to the rear portions of the right and left body frames 3, and the rear wheels 2 are attached to the rear wheel transmission cases 10. Right and left electric motors 11 (corresponding to transmissions) are provided. The right electric motor 11 is attached to the left portion of the right rear wheel transmission case 10, and the left electric motor 11 is attached to the right portion of the left rear wheel transmission case 10.

[0036] The power of the electric motor 11 is transmitted to the rear wheels 2 via a reduction mechanism (not shown) inside the rear wheel transmission case 10, thereby driving and rotating the rear wheels 2. The electric motor 11 can change speed continuously between the forward and reverse sides, and the right and left rear wheels 2 are driven and rotated by changing speed continuously between the forward and reverse sides independently of each other.

[0037] (Overview of Electric Motor Operation) As shown in Figures 1 and 2, the right shift lever 12 (corresponding to a manual operation device) is provided to the right of the driver's seat 8 (corresponding to the right part of the driver's section 27), and the left shift lever 12 (corresponding to a manual operation device) is provided to the left of the driver's seat 8 (corresponding to the left part of the driver's section 27).

[0038] The gear shift lever 12 can be operated in the front-rear direction from a neutral position N1 to a maximum forward speed position F1 forward from the neutral position N1 to a maximum reverse speed position R1 rearward from the neutral position N1. As will be described later, the operation position of the gear shift lever 12 is detected, and the operation position of the gear shift lever 12 is input to a control device (not shown).

[0039] When the speed change lever 12 is operated to the neutral position N1, the electric motor 11 is stopped by the control device. When the shift lever 12 is operated forward from the neutral position N1 to the forward drive side, the control device operates the electric motor 11 in the forward direction so as to achieve a forward drive speed corresponding to the operated position of the shift lever 12. When the shift lever 12 is operated to the maximum forward speed position F1, the control device operates the electric motor 11 at the maximum forward speed.

[0040] When the shift lever 12 is operated backward from the neutral position N1 to the reverse side, the control device operates the electric motor 11 in the reverse direction so as to achieve a reverse speed corresponding to the operating position of the shift lever 12. When the shift lever 12 is operated to the maximum reverse speed position R1, the control device operates the electric motor 11 at the maximum reverse speed.

[0041] The right and left rear wheels 2 are driven to rotate independently of each other in a stepless manner forward and backward by the right and left speed change levers 12. Because the right and left front wheels 1 are caster wheels, the right and left rear wheels 2 are driven to rotate independently of each other, thereby causing the vehicle body 4 to move forward and backward and turn right and left.

[0042] (Correspondence of the claims in the overall structure) The vehicle is provided with a body 4 having a driving section 27, and right and left running devices (rear wheels 2) provided on the body 4. The vehicle is provided with right and left transmissions (electric motors 11) that operate the right and left traveling devices (rear wheels 2), and the transmissions (electric motors 11) can be operated to a neutral position, a forward side, and a reverse side.

[0043] (Configuration of the support case that supports the gear shift lever) As shown in Figures 1 and 2, right and left support cases 13 are connected to right and left body frames 3. As shown in Figures 3 to 6, the support case 13 has an upper part 14, an outer part 15, an inner part 16, a front part 17, etc., and is configured in a box shape.

[0044] A fulcrum shaft 18 is attached in the left-right direction across a lower portion of the outer portion 15 and a lower portion of the inner portion 16. A guide plate 19 is connected to the upper portion 14 of the support case 13 and extends laterally outward from the upper portion 14 of the support case 13.

[0045] 3, the lever guide 20 is open across the upper part 14 of the support case 13 and the guide plate 19. The lever guide 20 has an opening along the front-rear direction and another opening extending laterally outward from the middle of the opening, and the connection part of the two openings is the neutral position N1 of the gear shift lever 12.

[0046] In the lever guide 20, the portion extending forward from the neutral position N1 is the forward travel guide portion 20a, and the front end portion of the forward travel guide portion 20a is the maximum forward speed position F1 of the shift lever 12.

[0047] In the lever guide 20, the portion extending rearward from the neutral position N1 is the reverse side travel guide portion 20b, and the rear end portion of the reverse side travel guide portion 20b is the maximum reverse speed position R1 of the shift lever 12. The portion extending laterally outward from the neutral position N1 is the neutral guide portion 20c.

[0048] (Gear shift lever configuration) 4, 5, and 6, the gear shift lever 12 has a base portion 21 and a lever portion 22. The base portion 21 has a boss portion 21a, an arm portion 21b, an operation plate 21c, a stopper portion 21d, and an operation pin 21e (corresponding to a connection portion).

[0049] In the base 21, the boss portion 21a is attached to the fulcrum shaft 18 so as to be able to swing, and the boss portion 21a is able to swing about an axis P1 (corresponding to a first axis) along the left-right direction of the fulcrum shaft 18. The arm portion 21b is attached to the boss portion 21a so as to be able to swing about an axis P3 (third axis) perpendicular to the axis P1.

[0050] In the base 21, an operation plate 21c is connected to the boss portion 21a and extends upward. A stopper portion 21d is connected to the upper end portion of the operation plate 21c and extends toward the arm portion 21b. An operation pin 21e is connected to the vertical middle portion of the operation plate 21c and extends in the opposite direction to the stopper portion 21d.

[0051] 1 and 2, the lever portion 22 is connected to the arm portion 21b of the base portion 21 and extends upward through the lever guide 20. A handle portion 22a to be held by an operator is provided on the upper portion of the lever portion 22. As shown in FIGS. 4, 5, and 6, a damper 23 is connected between the operation plate 21c of the base portion 21 and the machine frame 3.

[0052] 3 to 6, when an operator in the driver's seat 8 holds the handle portion 22a of the gear shift lever 12 (lever portion 22) and operates it back and forth, the gear shift lever 12 (base portion 21 and lever portion 22) is swung about the axis P1 and operated along the travel guide portions 20a, 20b of the lever guide 20. Rapid operation of the gear shift lever 12 in the forward and backward directions is suppressed by the damper 23.

[0053] When the gearshift lever 12 is operated laterally outward from the neutral position N1 of the lever guide 20, the lever portion 22 of the gearshift lever 12 swings laterally outward about the axis P3 relative to the base portion 21. As a result, the lever portion 22 of the gearshift lever 12 enters the neutral guide portion 20c of the lever guide 20 with the base portion 21 of the gearshift lever 12 remaining in the neutral position N1.

[0054] When the lever portion 22 of the shift lever 12 is operated from the neutral guide portion 20c of the lever guide 20 to the neutral position N1, the lever portion 22 of the shift lever 12 hits the stopper portion 21d of the base 21, and the lever portion 22 of the shift lever 12 is stopped at the neutral position N1 of the lever guide 20.

[0055] A neutral sensor 24 is attached to the outer portion 15 of the support case 13. The neutral sensor 24 detects that the lever portion 22 of the gear shift lever 12 is operated into the neutral guide portion 20c of the lever guide 20.

[0056] (Correspondence to claims regarding gear shift levers) The gear shift lever 12 is provided so as to be pivotable about a first axis (axis P1) and is manually operated.

[0057] The right manual operation device (shift lever 12) is a right shift lever 12 capable of operating the right transmission (electric motor 11), and is provided on the right side of the driver's section 27. The left manual operation device (shift lever 12) is a left shift lever 12 capable of operating the left transmission (electric motor 11), and is provided on the left side of the driver's section 27.

[0058] The shift lever 12 has a base 21 that is mounted on the body 4 so as to be swingable around a first axis (axis P1) that runs along the left-right direction, and a lever portion 22 that has a handle portion 22a at its upper portion that is held by an operator and is attached to the base 21 so as to be swingable around a third axis (axis P3) that runs along a direction perpendicular to the first axis (axis P1), and is swingable integrally with the base 21 around the first axis (axis P1).

[0059] A lever guide 20 is provided which has a neutral guide portion 20c capable of guiding the lever portion 22 in the left-right direction at the neutral position N1 of the operating range of the shift lever 12, and forward and reverse side travel guide portions 20a, 20b capable of guiding the lever portion 22 in the front-rear direction in the range other than the neutral position N1 of the operating range of the shift lever 12.

[0060] When the lever portion 22 is operated to the neutral position N1 and the neutral guide portion 20c within the operating range of the shift lever 12, the shift device (electric motor 11) is operated to the neutral position, and when the lever portion 22 is operated to the forward and reverse side travel guide portions 20a, 20b, the shift device (electric motor 11) is operated to the forward and reverse sides.

[0061] (Potentiometer configuration for detecting the operating position of the gear shift lever) As shown in FIGS. 3 to 6, the potentiometer 25 is disposed toward the left-right center of the body 4 with respect to the inner portion 16 of the support case 13, and is attached to the inner portion 16 of the support case 13 by an attachment member .

[0062] Since the inner portion 16 of the support case 13 is provided toward the left-right center of the body 4 relative to the outer portion 15 of the support case 13, the potentiometer 25 is disposed toward the left-right center of the driver's part 27 relative to the shift lever 12 (the side closer to the driver's seat 8).

[0063] The potentiometer 25 has a detection shaft 25a and a detection arm 25b. The detection shaft 25a is provided on the potentiometer 25 so as to be swingable around a shaft core P2 (corresponding to a second shaft core) along the left-right direction. The detection arm 25b is attached to the detection shaft 25a and extends upward. In this case, the fulcrum shaft 18 (shaft core P1) and the detection shaft 25a (shaft core P2) of the potentiometer 25 are aligned along the left-right direction and are parallel to each other.

[0064] The operating pin 21e of the shift lever 12 (base 21) engages with the free end of the detection arm 25b of the potentiometer 25, and the operating pin 21e of the shift lever 12 (base 21) and the detection arm 25b of the potentiometer 25 are connected.

[0065] As described above, when the gearshift lever 12 (base 21 and lever portion 22) is swung about axis P1 and operated along the travel guide portions 20a, 20b of the lever guide 20, the detection arm 25b of the potentiometer 25 swung about axis P2 in conjunction with the operation plate 21c and operation pin 21e of the gearshift lever 12 (base 21). The operation position of the gearshift lever 12 is detected by the potentiometer 25 via the base 21 of the gearshift lever 12 (operation plate 21c and operation pin 21e).

[0066] When the gear shift lever 12 is operated from the neutral position N1 of the lever guide 20 to the neutral guide portion 20c, the lever portion 22 of the gear shift lever 12 swings laterally outward about the axis P3 relative to the base portion 21 while the base portion 21 of the gear shift lever 12 is left in the neutral position N1. The potentiometer 25 maintains a detection state in which the operated position of the gear shift lever 12 is the neutral position N1 of the lever guide 20.

[0067] As the operating position of the right shift lever 12 is detected by the right potentiometer 25, as described above, the control device stops the right electric motor 11, operates it in the forward rotation side (forward rotation side), or operates it in the reverse rotation side (reverse rotation side). As a result of the operation position of the left shift lever 12 being detected by the left potentiometer 25, as described above, the control device stops the left electric motor 11, operates it in the forward rotation side (forward movement side), or operates it in the reverse rotation side (reverse movement side).

[0068] (Correspondence to claims regarding the potentiometer configuration that detects the operating position of the gear shift lever) A potentiometer 25 is provided, which has a detection arm 25b that can swing around a second axis (axis P2) that is aligned with the first axis (axis P1), and the free end of the detection arm 25b is connected to an manual operation device (gear shift lever 12). The potentiometer 25 is provided closer to the left and right center of the driving section 27 than the gear shift lever 12.

[0069] In conjunction with the operation of the manual operating device (gear shift lever 12) around the first axis (axis P1), the detection arm 25b is operated around the second axis (axis P2), thereby detecting the operating position of the manual operating device (gear shift lever 12) by the potentiometer 25.

[0070] The right transmission (electric motor 11 ) is operated based on the detection value of the right potentiometer 25 , and the left transmission (electric motor 11 ) is operated based on the detection value of the left potentiometer 25 .

[0071] (Gear shift lever operating range) As shown in FIGS. 1 and 3, the speed change lever 12 (arm portion 21b) is operated among a neutral position N1, a maximum forward speed position F1, and a maximum reverse speed position R1. The distance between the neutral position N1 and the maximum reverse speed position R1 is set to be slightly shorter than the distance between the neutral position N1 and the maximum forward speed position F1, and the maximum reverse speed position R1 is set to be slightly slower than the maximum forward speed position F1.

[0072] As shown in FIG. 7, within the operating range (operating angle) B1 (the range spanning the maximum forward speed position F1 and the maximum reverse speed position R1) of the shift lever 12 (arm portion 21b), the central position B11 of the operating range (operating angle) B1 is located on the side closer to the maximum forward speed position F1 than the neutral position N1.

[0073] (detection range of potentiometer 25) As shown in FIGS. 3 to 6, detection arm 25b of potentiometer 25 is connected to shift lever 12 (arm portion 21b) via operation pin 21e of shift lever 12 (arm portion 21b). As shown in FIG. 7, when viewed from the direction of the axis P1, the detection axis 25a (axis P2) of the potentiometer 25 is disposed at the neutral position N1.

[0074] When viewed from the direction of the axis P1, the detection axis 25a (axis P2) of the potentiometer 25 is positioned closer to the fulcrum axis 18 (axis P1) than the operating pin 21e of the shift lever 12 (base 21), and is positioned within the operating range (operating angle) B1 (positioned between the maximum forward speed position F1 and the maximum reverse speed position R1).

[0075] The length from the fulcrum axis 18 (axis center P1) of the shift lever 12 (arm portion 21b) to the operating pin 21e (corresponding to the first length from the first axis center to the connection part between the free end of the detection arm and the manual operating tool) is defined as the first length L1.

[0076] The length from the detection axis 25a (axis core P2) of the potentiometer 25 to the operating pin 21e of the shift lever 12 (arm portion 21b) (corresponding to the second length from the second axis core to the connection part between the free end of the detection arm and the manual operating tool) is the second length L2.

[0077] The second length L2 changes slightly as the gearshift lever 12 (arm portion 21b) is operated around the fulcrum shaft 18 (axis center P1), and the second length L2 is longest when the gearshift lever 12 (arm portion 21b) is operated to the maximum forward speed position F1. Even when the second length L2 is at its longest, the second length L2 is shorter than the first length L1.

[0078] In the detection range (detection angle) C1 of the detection arm 25b of the potentiometer 25, a central position C11 of the detection range (detection angle) C1 is located on the side closer to the maximum forward speed position F1 than the neutral position N1.

[0079] When the detection range (detection angle) of potentiometer 25 (the rotatable angle of detection shaft 25a of potentiometer 25), which is the range within which potentiometer 25 can output a detection value, is detection range (detection angle) C1, when shift lever 12 (arm portion 21b) is operated to maximum forward speed position F1 (corresponding to one end of operating range (operation angle) B1 of the manual operating tool), detection arm 25b of potentiometer 25 is positioned at one end of detection range (detection angle) C1.

[0080] When the detection range (detection angle) of the potentiometer 25 (rotatable angle of the detection shaft 25a of the potentiometer 25), which is the range in which the potentiometer 25 can output a detection value, is the detection range (detection angle) C1, when the shift lever 12 (arm portion 21b) is operated to the maximum reverse speed position R1 (corresponding to the other end of the operation range (operation angle) B1 of the manual operation tool), the detection arm 25b of the potentiometer 25 is located at the other end of the detection range (detection angle) C1. The detection range (detection angle) C1 is larger than the operation range (operation angle) B1.

[0081] As a result, the operation of the gear shift lever 12 (arm portion 21b) around the fulcrum shaft 18 (axis core P1) is magnified and transmitted to the detection arm 25b of the potentiometer 25, so that the operation of the detection arm 25b of the potentiometer 25 becomes larger than the operation of the gear shift lever 12 (arm portion 21b).

[0082] (Correspondence of the claims regarding the operating range of the gear shift lever and the detection range of the potentiometer) The first axis core (axis core P1) and the second axis core (P2) are arranged at a position where the first length L1 from the first axis core (axis core P1) to the connection portion (operation pin 21e) between the free end of the detection arm 25b and the manual operating device (speed change lever 12) and the second length L2 from the second axis core (axis core P2) to the connection portion (operation pin 21e) between the free end of the detection arm 25b and the manual operating device (speed change lever 12) is shorter than the first length L1.

[0083] The second shaft core (shaft core P2) is disposed closer to the first shaft core (shaft core P1) than the connection portion (operation pin 21e) between the free end of detection arm 25b and the manual operation device (speed change lever 12). The second shaft core (shaft core P2) is disposed within an operating range (operating angle) B1 of the manual operating device (gear shift lever 12) when viewed from the direction of the first shaft core (shaft core P1).

[0084] (First Alternative Embodiment of the Invention) In the configuration shown in FIG. 7, it is also possible to configure the detection axis 25a (axis P2) of the potentiometer 25 so as not to be located at the neutral position N1 when viewed from the direction of the axis P1 (see FIG. 8).

[0085] When the distance between the neutral position N1 and the maximum reverse speed position R1 is set to be slightly shorter than the distance between the neutral position N1 and the maximum forward speed position F1, it is preferable that the detection shaft 25a (axis core P2) of the potentiometer 25 is positioned on the side closer to the maximum forward speed position F1 than the neutral position N1, as shown in FIG. 8.

[0086] (Second Alternative Embodiment of the Invention) In the configuration shown in FIG. 7, when the distance between the neutral position N1 and the highest reverse speed position R1 is the same as the distance between the neutral position N1 and the highest forward speed position F1 (when the highest forward speed position F1 and the highest reverse speed position R1 are at the same speed), it is preferable to configure as shown in FIG. 9.

[0087] 9, when viewed from the direction of the axis P1, the detection axis 25a (axis P2) of the potentiometer 25 is located at the neutral position N1, so that the area on the side of the maximum forward speed position F1 and the area on the side of the maximum reverse speed position R1 are symmetrical with respect to the neutral position N1 when viewed from the direction of the axis P1. The neutral position N1, the center position B11 of the operation range (operation angle) B1, and the center position C11 of the detection range (detection angle) C1 coincide with each other.

[0088] As shown in FIG. 9, when viewed from the direction of axis P1, an imaginary line D1 is assumed to pass through the operating pin 21e (the free end of the detection arm 25b of the potentiometer 25) of the shift lever 12 (arm portion 21b) and the fulcrum shaft 18 (axis P1).

[0089] When the shift lever 12 (arm portion 21b) is operated to the neutral position N1 (central position B11, C11) (when the operating pin 21e of the shift lever 12 (arm portion 21b) is located in the neutral position N1 (central position B11, C11)), the imaginary line D1 is located in the neutral position N1 (central position B11, C11), and is located on the detection axis 25a (axis core P2) of the potentiometer 25.

[0090] (Correspondence of the claims regarding the operating range of the gear shift lever and the detection range of the potentiometer) When the manual operating device (speed change lever 12) is positioned at the center position B11 of the operating range (operating angle) B1 of the manual operating device (speed change lever 12), the second shaft core (shaft core P2) is positioned so that, when viewed from the direction of the first shaft core (shaft core P1), the second shaft core (shaft core P2) is located on a virtual line D1 that passes through the connection part (operating pin 21e) between the free end of the detection arm 25b and the manual operating device (speed change lever 12) and the first shaft core (shaft core P1).

[0091] (Third Alternative Embodiment of the Invention) In the configuration shown in Figures 7, 8 and 9, the positional relationship between the detection arm 25b of the potentiometer 25 and the operating pin 21e of the shift lever 12 (arm portion 21b) may be reversed upside down, so that the detection arm 25b of the potentiometer 25 extends downward from the detection shaft 25a of the potentiometer 25 and is connected to the operating pin 21e of the shift lever 12 (arm portion 21b).

[0092] According to the above-described configuration, when viewed from the direction of axis P1, the detection axis 25a (axis P2) of the potentiometer 25 is positioned farther from the fulcrum axis 18 (axis P1) than the operating pin 21e of the shift lever 12 (base 21), and is positioned within the operating range (operating angle) B1 (positioned between the maximum forward speed position F1 and the maximum reverse speed position R1).

[0093] (Fourth Alternative Embodiment of the Invention) The detection range (detection angle) of potentiometer 25 (rotatable angle of detection shaft 25a of potentiometer 25), which is the range within which potentiometer 25 can output a detection value, may be greater than detection range (detection angle) C1 shown in FIGS.

[0094] According to the above-described configuration, when the shift lever 12 (arm portion 21b) is operated to the maximum forward speed position F1 (corresponding to one end of the operating range (operating angle) B1 of the manual operating tool), the detection arm 25b of the potentiometer 25 may not be positioned at one end of the detection range (detection angle). When the shift lever 12 (arm portion 21b) is operated to the maximum reverse speed position R1 (corresponding to the other end of the operating range (operating angle) B1 of the manual operating tool), the detection arm 25b of the potentiometer 25 may not be positioned at the other end of the detection range (detection angle).

[0095] (Fifth Alternative Embodiment of the Invention) Instead of the electric motor 11, an engine (not shown) and hydrostatic right and left continuously variable transmissions (corresponding to a transmission) (not shown) may be provided. According to this configuration, the power of the engine is transmitted to the right continuously variable transmission, where the speed is changed, and then transmitted to the right rear wheel 2. The power of the engine is transmitted to the left continuously variable transmission, where the speed is changed, and then transmitted to the left rear wheel 2. Based on the operational positions of the right and left shift levers 12, the right and left continuously variable transmissions are operated by right and left electric actuators (not shown).

[0096] (Sixth Alternative Embodiment of the Invention) Instead of the front wheels 1 and rear wheels 2, right and left crawler type running devices (not shown) may be provided. In this case, the engine power may be transmitted to a single continuously variable transmission (equivalent to a transmission) where it is changed in speed, and then transmitted from the continuously variable transmission to the right and left traveling devices, and the continuously variable transmission may be operated by an electric actuator (not shown) based on the operating position of a single transmission lever 12.

[0097] (Seventh Alternative Embodiment of the Invention) The driver's seat 8 does not necessarily have to be provided in the driver's section 27. According to this configuration, the operator boards the machine body 4 while standing in the driver's section 27.

[0098] (Eighth Alternative Embodiment of the Invention) When a work vehicle is equipped with a lifting device (not shown) for raising and lowering a working implement (such as a rotary tilling implement) (not shown) attached to the body 4, and a lifting lever (corresponding to a manual operating tool) (not shown) for raising and lowering the lifting device, the present invention may be adopted as described below.

[0099] The operation position of the lift lever is detected by potentiometer 25. When the lift lever is operated within the operation range (operation angle) B1, the lift device operates so that the working device is positioned at a height corresponding to the operation position of the lift lever. The minimum position of the operating range (operating angle) B1 of the lift lever corresponds to the minimum position of the lift device, and the maximum position of the operating range (operating angle) B1 of the lift lever corresponds to the maximum position of the lift device. [Industrial Applicability]

[0100] The present invention can be applied not only to riding mowers, but also to tractors, and also to construction work vehicles such as backhoes and wheel loaders. [Explanation of symbols]

[0101] 2 Rear wheels (running gear) 4. Aircraft 11 Electric motor (transmission) 12 Gear shift lever (manually operated device) 20 Lever guide 20a Travel guide unit 20b Travel guide unit 20c Inside planning 21 Base 21e Operation pin (connection part) 22 Lever section 22a Handle 25 Potentiometer 25b Detection arm 27 Driving Department B1 Operation Range B11 Center position C1 Detection Range D1 Virtual Line L1 First length L2 Second length N1 Neutral position P1 axis (1st axis) P2 axis (second axis) P3 axis (third axis)

Claims

1. An aircraft having a driving section; Right and left running devices provided on the aircraft body; An artificial operating tool that is provided so as to be swingable about a first axis and is manually operated; a potentiometer having a detection arm that can swing around a second axis along the first axis, the free end of the detection arm being connected to the manual operation tool; In conjunction with the operation of the manual operation tool around the first axis, the detection arm is operated around the second axis, whereby the operation position of the manual operation tool is detected by the potentiometer; A work vehicle in which the first axle core and the second axle core are arranged at a position where a first length from the first axle core to a connection portion between the free end of the detection arm and the manual operating tool, and a second length from the second axle core to a connection portion between the free end of the detection arm and the manual operating tool, the second length being shorter than the first length.

2. The work vehicle of claim 1, wherein the second axle is positioned so that when the manual operating tool is located at the center position of the operating range of the manual operating tool, when viewed from the direction of the first axle, the second axle is located on a virtual line passing through the connection part between the free end of the detection arm and the manual operating tool and the first axle.

3. 2. The work vehicle according to claim 1, wherein the second shaft is disposed closer to the first shaft than a connection portion between the free end of the detection arm and the manual operation tool.

4. 4. The work vehicle according to claim 3, wherein the second shaft is disposed within an operating range of the manual operation tool when viewed from the direction of the first shaft.

5. A right and left transmission is provided for operating the right and left traveling devices, The right manual operation tool is a right shift lever capable of operating the right transmission, and is provided on the right side of the driving section; The left manual operation tool is a left shift lever capable of operating the left transmission, and is provided on the left side of the driving section; 5. A work vehicle as claimed in any one of claims 1 to 4, wherein the right transmission is operated based on the detection value of the right potentiometer, and the left transmission is operated based on the detection value of the left potentiometer.

6. 6. The work vehicle according to claim 5, wherein the potentiometer is provided closer to the left and right center of the driver's section than the speed change lever.

7. The transmission can be operated to a neutral position, a forward position, and a reverse position, the shift lever has a base portion provided on the machine body so as to be swingable about the first axis along the left-right direction, and a lever portion having a handle portion to be held by an operator provided at an upper portion, attached to the base so as to be swingable about a third axis along a direction perpendicular to the first axis, and swingable integrally with the base about the first axis, The potentiometer detects an operational position of the base; A lever guide is provided that has a neutral guide portion that can guide the lever portion in a direction along the left-right direction at a neutral position of the operation range of the shift lever, and forward and reverse travel guide portions that can guide the lever portion along the front-rear direction in a range other than the neutral position of the operation range of the shift lever, 6. A work vehicle as described in claim 5, wherein when the lever portion is operated to a neutral position and to the neutral guide portion within the operating range of the shift lever, the shift device is operated to the neutral position, and when the lever portion is operated to the forward and reverse side travel guide portions, the shift device is operated to the forward and reverse sides.

Images