JP4824643B2 - Shift operating tool for work vehicle - Google Patents

Description

  The present invention relates to a transmission operating tool for a work vehicle.

A main transmission operating tool for performing a shifting operation of the traveling main transmission device by electric control is provided in a grip portion of the auxiliary transmission lever for performing a shifting operation of the traveling auxiliary transmission device, and the shifting of the traveling main transmission device is performed while the auxiliary transmission lever is held. Patent Documents 1 and 2 that can be operated are known as gear shifting operation tools for work vehicles.
JP 2002-127774 A JP 2002-177871 A

However, since the shift operating tool for the work vehicle shown in the above document is configured such that the main shift operating tool performs the acceleration / deceleration of the traveling main transmission by pressing, the operator grips the grip portion of the sub-shift lever. In this case, there is a problem that the main transmission operating tool may be erroneously operated. In addition, when operating the main gearshift operation tool while holding the auxiliary gearshift lever, the finger to push is limited to a specific finger, so the operator has to operate with the thumb finger even if he wants to operate with the finger. In some cases, there is a case where it is not possible to operate with the thumb, but there is a case where it is necessary to operate with the hunger, and the versatility is low.
The present invention solves the above-described problems, and includes a main transmission operating tool for performing a shift operation of the traveling main transmission by electric control provided in a grip portion of an auxiliary transmission lever that performs a shifting operation of the traveling auxiliary transmission. An object of the present invention is to prevent erroneous operation of a main transmission operating tool by gripping a transmission lever and to provide a highly versatile transmission operating tool for a work vehicle.

  In order to solve the above-described problems, the gear shifting operation tool for the work vehicle according to the present invention firstly performs the gear shifting operation of the traveling sub-transmission device 19 using the main gear shifting operation tool 99 for performing the gear shifting operation of the traveling main transmission device 16 by electric control. In the shift operation tool of the work vehicle provided in the grip portion 98 of the sub-transmission lever 12, the main transmission operation tool 99 is supported on the side surface on the operator side of the sub-transmission lever 12 so as to be able to turn back and forth. In addition, the operator has formed a thumb operating piece 102 for rotating with a thumb and an eating finger operating piece 103 for rotating with a forefinger while gripping the grip portion 98 of the auxiliary transmission lever 12.

  Second, the speed increasing operation piece 102a for speeding up operation with a thumb and the speed reducing operation piece 102b for speeding down operation with a thumb are the characteristics of the thumb operating piece 102 of the main transmission operating tool 99.

  Thirdly, the anti-slip portion 104 is formed on the thumb operating piece 102 or the forefinger operating piece 103 of the main transmission operating tool 99.

  According to the shift operation tool of the work vehicle of the present invention configured as described above, the main shift operation tool can be rotated by either the thumb or the clerk while holding the grip of the sub-shift lever. In addition to improving the versatility of the main transmission operating tool, the shifting operation of the traveling main transmission is not performed unless the main transmission operating tool is rotated with respect to the grip of the auxiliary transmission lever even when the auxiliary transmission lever is held. Therefore, an erroneous operation of the main transmission operating tool by holding the auxiliary transmission lever is prevented.

  In addition, the operability of the main transmission operation tool is further improved by configuring the heel operation piece of the main transmission operation tool by the acceleration operation piece for the speed increase operation by the thumb and the deceleration operation piece for the deceleration operation by the thumb. To do.

  Furthermore, the operability of the main transmission operation tool is further improved by forming the anti-slip portion on the thumb operation piece and the cleaver operation piece of the main transmission operation tool.

  FIG. 1 is an overall plan view of a tractor to which a shift operation tool for a work vehicle according to the present invention is applied. The tractor is a rotary tiller that is connected to a traveling machine body 1, a pair of left and right front wheels 2, 2 and rear wheels 3, 3 that support the traveling machine body 1, and a rear side of the traveling machine body 1 via a link mechanism 4. And a work machine (not shown) such as a machine, and configured to perform work by the work machine while driving the traveling machine body 1 to travel.

  The traveling machine body 1 includes a bonnet 7 in which an engine 6 (see FIG. 2) is provided, and a driver's seat 8 provided at the rear of the bonnet 7. The driver's seat 8 is provided with a steering handle 11 in front of a seat 9 on which an operator is seated, and an auxiliary transmission lever 12 supported on the left side of the seat 9.

  FIG. 2 is a power transmission system diagram of the tractor. The power of the engine 6 is transmitted through the transmission 13 to the front wheels 2, the rear wheels 3, and the PTO shaft 14 that drives the work machine. The transmission 13 includes a main transmission 16 (traveling main transmission) that performs eight-stage traveling shift switching, a main clutch 17 that is a hydraulic clutch that performs power switching, and a forward / reverse switching that performs forward / backward switching of the traveling machine body 1. Device 18 and a sub-transmission device 19 (traveling sub-transmission device) that performs two-stage traveling shift switching. The main transmission device 16 includes a first main transmission unit 16A and a second main transmission unit 16B. It is configured. Then, the power on the engine 6 side is transmitted in the order of the first main transmission unit 16A → the main clutch 17 → the forward / reverse switching device 18 → the second main transmission unit 16B → the auxiliary transmission device 19.

  The power of the engine 13 is transmitted to the transmission shaft 22 through a clutch 21 that is turned on and off by an operator.

  The first main transmission unit 16A includes four input gears 23a, 23b, 23c, and 23d that are integrally fixed to the transmission shaft 22, and four output gears that always mesh with the corresponding input gears 23a, 23b, 23c, and 23d. 24a, 24b, 24c, and 24d. The four output gears 24a, 24b, 24c, and 24d are rotatably supported by the transmission shaft 26, and the power of the transmission shaft 22 is always transmitted.

  Among the four output gears 24a, 24b, 24c, 24d, a synchromesh type shift member 27 is provided between the two output gears 24a, 24b on the upstream side of the power transmission. The shift member 27 engages one of the two output gears 24a and 24b with the transmission shaft 26 and disengages the other from the transmission shaft 26, thereby generating power for the two output gears 24a and 24b. It is configured to selectively transmit to the transmission shaft 26. Further, when the shift member 27 is positioned at an intermediate position (neutral position) between the two output gears 24 a and 24 b, a neutral state is established in which the power of the two output gears 24 a and 24 b is not transmitted to the transmission shaft 26.

  On the other hand, among the four output gears 24a, 24b, 24c, 24d, a shift member 28 having substantially the same configuration as the shift member 27 is also provided between the two output gears 24c, 24d on the downstream side of the power transmission, The power of either one of the two output gears 24c and 24d is selectively transmitted to the traveling shaft 21.

  Then, the two shift members 27 and 28 are operated so that any one of the four output gears 24a, 24b, 24c, and 24d is transmitted to the transmission shaft 26. 16 A of 1st main transmission parts are comprised so that a four-stage driving | running | working transmission switching can be performed as mentioned above.

  The main clutch 17 performs on / off operation of power transmission from the transmission shaft 26 to the transmission shaft 29.

  The forward / reverse switching device 18 includes two input gears 31 a and 31 b that are integrally fixed to the transmission shaft 29, two output gears 33 a and 33 b that are rotatably supported on the transmission shaft 32, and an intermediate gear 34. It has. While the input gear 31b on the downstream side of power transmission and the output gear 33b are always meshed, the power of the input gear 31a on the upstream side of power transmission is transmitted to the corresponding output gear 33a via the intermediate gear 34. For this reason, the output gear 33a on the upstream side of the power transmission and the output gear 33b on the downstream side of the power transmission are always driven to rotate in opposite directions. A shift member 36 having substantially the same configuration as that of the shift member 27 described above is provided between the two output gears 33a and 33b, and the power of either one of the two output gears 33a and 33b is selectively selected. Therefore, it is possible to perform forward / reverse switching of the transmission shaft 32, that is, forward / backward switching of the traveling machine body 3.

  The second main transmission unit 16B includes two input gears 37a and 37b that are rotatably supported by the transmission shaft 32, and two output gears 39a and 39b that are integrally fixed to the transmission shaft 38. The input gears 37a and 37b are always meshed with the corresponding output gears 39a and 39b. Between the two input gears 37a and 37b, a shift member 41 having substantially the same configuration as the shift member 27 described above is provided. The power of the transmission shaft 32 is transmitted to the transmission shaft 38 by one of the two input gears 37a and 37b by the shift member 41. The second main transmission unit 16B is configured to be able to perform two-stage traveling shift switching as described above. Then, the main transmission 16 constituted by the first main transmission unit 16A and the second main transmission unit 16B can perform a total of eight stages of traveling shifts at 4 × 2.

  The auxiliary transmission 19 includes two input gears 42a and 42b that are integrally fixed to the transmission shaft 38, two intermediate gears 43a and 43b that always mesh with the corresponding input gears 42a and 42b, and a corresponding intermediate gear 43a. , 43b and two output gears 44a, 44b that always mesh with each other. The intermediate gears 43 a and 43 b are rotatably supported on the transmission shaft 46, and the output gears 44 a and 44 b are rotatably supported on the drive shaft 47. Between the two output gears 44a and 44b, a shift member 48 having substantially the same configuration as that of the shift member 27 described above is provided, and the power of the two output gears 44a and 44b is driven by the shift member 48 to the drive shaft. 47 is selectively transmitted. The auxiliary transmission 19 is configured to be able to perform two-stage traveling shift switching as described above.

  The power of the drive shaft 47 is always transmitted to the rear wheel 3 via the differential gear 49. On the other hand, the power transmission from the drive shaft 47 to the front wheel 2 is turned on and off by the switching member 51. The switching member 51 includes a small-diameter gear 51a and a large-diameter gear 51b that mesh with a front-wheel drive gear 52 that is integrally fixed to the drive shaft 47, and is supported by the transmission shaft 46 so as to be reciprocally movable in the axial direction. 46 is configured to rotate integrally with the motor 46.

  By reciprocating the switching member 51, the front wheel drive gear 52 and the small diameter gear 51a are engaged and disengaged. When the small-diameter gear 51a and the front wheel drive gear 52 are engaged, the power of the drive shaft 47 is transmitted to the front wheels 2 to drive the traveling machine body 3 to four-wheel drive, while the small-diameter gear 51a and the front wheel drive gear 52 are engaged. When is released, the power transmission from the drive shaft 47 to the front wheels 2 is cut off, and the traveling machine body 3 becomes a two-wheel drive.

  The power of the switching member 51 is transmitted to the front wheel 2 via the quick turn device 53 and the differential gear 54. The quick turn device 53 is configured to transmit the power of the switching member 51 to the differential gear 54 via a gear 56 that rotates integrally with the large-diameter gear 51 b or the transmission shaft 46. When the power of the large-diameter gear 51b is transmitted to the differential gear 54, the front wheel 2 is rotationally driven at a speed approximately twice that of the rear wheel 3, and the traveling machine body 1 is switched to the rapid turning mode. The On the other hand, when the power of the gear 56 is transmitted to the differential gear 54, the front wheels 2 are rotationally driven at substantially the same speed as the rear wheels 3, and the traveling machine body 1 is switched to the normal turning mode.

  In the transmission 13 configured as described above, the main transmission device 16 and the forward / reverse switching device 18 are changed in speed by a hydraulic control device 57 described later, and the auxiliary transmission device 19 is changed in speed by the auxiliary transmission lever 12 described above. The sub-transmission lever 12 is mechanically connected to the shift member 48 of the sub-transmission device 19 through a link mechanism, a wire, and the like, and the shift member 48 is operated by a swinging operation so that the traveling machine body 1 travels at a high speed. The operation is switched to one of a state, a neutral state, and a low-speed traveling state.

Next, the hydraulic control device 57 will be described.
FIG. 3 shows a hydraulic circuit of the hydraulic control device. The hydraulic control measure 57 includes a proportional pressure control solenoid valve 58, a first speed solenoid valve 59, a second speed solenoid valve 61, a third speed solenoid valve 62, a fourth speed solenoid valve 63, a high / low speed solenoid valve 64, and front and rear. The first and second speed cylinders 67 and 67, which are hydraulic cylinders controlled to be expanded and contracted by the forward switching solenoid valve 66, the first speed solenoid valve 59 and the second speed solenoid valve 61, and the expansion and contraction are controlled by the third speed solenoid valve 62 and the fourth speed solenoid valve 63. A three-speed / four-speed cylinder 68 which is a hydraulic cylinder, a high / low speed shift cylinder 69 which is a hydraulic cylinder controlled to be expanded / contracted by a high / low speed solenoid valve 64, and a forward / backward cylinder which is a hydraulic cylinder controlled to be expanded / contracted by a forward / reverse switching solenoid valve 66. Switching cylinder 71 , And a hydraulic pressure sensor 72 for measuring the pressure inside the apparatus, the oil temperature sensor 73 for measuring the temperature inside the device. Then, pressure oil is supplied into the hydraulic control device 54 by the oil pump 74.

  The proportional pressure control solenoid valve 58 is an electromagnetic switching valve that switches on and off the main clutch 17 by adjusting the pressure of the pressure oil supplied from the oil pump 74 to the main clutch 17. Controlled by a control signal. The pressure of the pressure oil supplied to the main clutch 17 is sensed by the aforementioned hydraulic sensor 72 and the information is fed back to the control device 76.

  In the first-speed / second-speed cylinder 67, a shift piston 77 that is expanded and contracted is engaged with a shift member 27 on the upstream side of the first main transmission unit 16A, and when the shift piston 77 is in a contracted state, the first main transmission unit 16A upstream The power on one side of the two output gears 24a, 24b on the side is transmitted to the transmission shaft 26, and the power on the other side of the two output gears 24a, 24b is transmitted to the transmission shaft 26 in the extended state. When the shift piston 77 is contracted or expanded, one of the two notches 77a and 77b provided in the shift piston 77 is engaged with the pin 78 and the contracted or expanded state is maintained. On the other hand, when the pin 78 is positioned between the two notches 77a and 77b and is not engaged with any of the notches 77a and 77b, the shift member 27 is in a neutral state and the above-described 1 A check valve 79 provided corresponding to the high-speed 2-speed cylinder 67 is opened, the pressure oil supplied to the main clutch 17 is reduced, and the main clutch 17 is turned off. That is, the main clutch 17 is automatically turned off during the shift change by the shift member 27, and the main clutch 17 is automatically turned on when the shift change is completed.

  In the third and fourth speed cylinder 68, a shift piston 81 that is extended and contracted is engaged with a shift member 28 on the downstream side of the first main transmission portion 16A, and when the shift piston 81 is in a contracted state, the first main transmission portion 16A is downstream. Power on one side of the two output gears 24c, 24d on the side is transmitted to the transmission shaft 26, and power on the other side of the two output gears 24c, 24d is transmitted to the transmission shaft 26 in the extended state. When the shift piston 81 is contracted or expanded, one of the two notches 81a and 81b provided on the shift piston 81 is engaged with the pin 82 and the contracted or expanded state is maintained. On the other hand, when the pin 82 is positioned between the two notches 81a and 81b and is not engaged with any of the notches 81a and 81b, the shift member 28 is in a neutral state, and the 3 The check valve 83 provided corresponding to the high-speed 4-speed cylinder 68 is opened, the pressure oil supplied to the main clutch 17 is reduced, and the main clutch 17 is turned off.

  Note that the check valves 79 and 83 of the two hydraulic cylinders 67 and 68 are connected in series, and the pressure oil supplied to the main clutch 17 is not reduced unless both the check valves 79 and 83 are opened. Therefore, only one of the powers of the four output gears 24 a, 24 b, 24 c, 24 d is transmitted to the transmission shaft 26.

  In the high / low speed change cylinder 69, the shift piston 84 that is extended and contracted is engaged with the shift member 41 of the second main transmission portion 16B, and when the shift piston 84 is in the contracted state, the power of the transmission shaft 32 is supplied to the second main transmission portion. 16B is transmitted to one side of the two input gears 37a and 37b, and the power of the transmission shaft 32 is transmitted to the other side of the two input gears 37a and 37b in the extended state. When the shift piston 84 is in the contracted or expanded state, one of the two notches 84a and 84b provided in the shift piston 84 is engaged with the pin 86 and the contracted or expanded state is maintained. On the other hand, when the pin 86 is moving between the two notches 84a and 84b and is not engaged with any of the notches 84a and 84b, the shift member 41 is in a neutral state. At the same time, the check valve 87 provided corresponding to the high / low speed change cylinder 69 is opened, the pressure oil supplied to the main clutch 17 is reduced, and the main clutch 17 is turned off. When the forward / reverse switching is completed, the decompression of the pressure oil supplied to the main clutch 17 is released, and the main clutch 17 enters the engaged state.

  In the forward / reverse switching cylinder 71, a shift piston 88 that is expanded and contracted is engaged with a shift member 36 of the forward / reverse switching device 18, and when the shift piston 88 is in a contracted state, the two output gears 33a of the forward / reverse switching device 18 are used. , 33b is transmitted to the transmission shaft 32, and the other power of the two output gears 33a, 33b is transmitted to the transmission shaft 32 in the extended state. When the shift piston 88 is contracted or expanded, one of the two notches 88a and 88b provided on the shift piston 88 is engaged with the pin 89 to maintain the contracted or expanded state. On the other hand, when the pin 89 is moving between the two notches 88a and 88b and is not engaged with any of the notches 88a and 88b, the shift member 36 is in a neutral state. At the same time, the check valve 91 provided corresponding to the forward / reverse switching cylinder 71 is opened, the pressure oil supplied to the main clutch 17 is reduced, and the main clutch 17 is turned off. When the forward / reverse switching is completed, the decompression of the pressure oil supplied to the main clutch 17 is released, and the main clutch 17 enters the engaged state.

Next, the control device 76 will be described.
FIG. 4 is a block diagram of the control device. The control device 76 is configured by a microcomputer or the like. On the input side, a neutral switch SW1 (stage clear switch) for setting the main transmission 16 in a neutral state and a shift-up switch SW2 (switching for increasing the speed of the main transmission 16) ( (Acceleration switch), shift-down switch SW3 (deceleration switch) for decelerating and switching the main transmission 16, engine rotation sensor 92 for detecting the rotational speed of the engine 6, and axle for detecting the rotational speed of the axle of the traveling machine body 1 Rotation sensor 93, the aforementioned hydraulic sensor 72, the aforementioned hot oil sensor 73, a forward / reverse sensor 94 for detecting a forward / reverse switching operation by a forward / reverse switching operation tool (not shown), and an on / off state of the main clutch 17 Is connected to the main clutch sensor 96.

  On the other hand, on the output side of the control device 76, the first speed solenoid valve 59, the second speed solenoid valve 61, the third speed solenoid valve 62, the fourth speed solenoid valve 63, the high and low speed solenoid valve 64, the proportional pressure control solenoid valve 58, and the front and rear A forward switching solenoid valve 66 is connected.

  Based on the input signals from the devices 72, 73, 92, 93, 94, 96, SW1, SW2, SW3 connected to the input side, the control device 76 is connected to the devices 58, 59, 61, connected to the output side. Output signals are output to 62, 63, 64, and 66, and the operations of the main transmission 16, the main clutch 17, and the forward / reverse switching device 18 are controlled.

  Note that the first speed solenoid valve 59, the second speed solenoid valve 61, the third speed solenoid valve 62, the fourth speed solenoid valve 63, and the high / low speed shift solenoid valve are operated by turning ON / OFF the neutral switch SW1, the shift up switch SW2, and the shift down switch SW3. 64 ON / OFF patterns are switched and the main transmission 16 is switched.

  FIG. 5 is an explanatory diagram showing a shift pattern of the main transmission. When the high / low speed shifting solenoid valve 64 and the first speed solenoid valve 59 are in the ON state, the main transmission 16 is in the first speed state, and when the high / low speed shifting solenoid valve 64 and the second speed solenoid valve 61 are in the ON state, the main transmission 16 is When the second speed state is reached and the high / low speed solenoid valve 64 and the third speed solenoid valve 62 are in the ON state, the main transmission 16 is in the third speed state, and the high / low speed solenoid valve 64 and the fourth speed solenoid valve 63 are in the ON state. When the main transmission 16 is in the fourth speed state and only the first speed solenoid valve 59 is in the ON state, the main transmission 16 is in the fifth speed state and only the second speed solenoid valve 61 is in the ON state. If 16 is in the 6th speed state and only the 3rd speed solenoid valve 62 is in the ON state, the main transmission 16 is in the 7th speed state and the 4th speed solenoid When only the id valve 63 is in the ON state, the main transmission 16 is in the eighth speed state, and when all the five solenoid valves 59, 61, 62, 63, 64 are in the OFF state, the main transmission 16 is in the neutral state. .

  FIG. 6 is a flowchart of the control device. When the shift control of the main transmission 16 is started, the process proceeds to step S1. In step S1, the on / off operation of the switches SW1 to SW3 is detected, and the process proceeds to step S2. In step S2, the presence or absence of a neutral switching operation by the neutral switch SW1 is determined based on the detection in step S1. If there is no neutral switching operation, the process proceeds to step S3. If there is a neutral switching operation, the process proceeds to step S4. move on.

  In step S3, based on the detection in step S1, the presence / absence of a shift operation by the shift up switch SW2 or the shift down switch SW3 is determined. If there is a shift operation, the process proceeds to step S5. The process returns to step S1. In step S5, the presence / absence of a speed increasing operation by the upshift switch SW2 is detected. If there is no speed increasing operation, the process proceeds to step S6, and if the speed increasing operation is performed, the process proceeds to step S7.

  In step S4, the set speed is set to neutral, and the process proceeds to step S8. In step S6, it is considered that a deceleration operation has been performed by the shift down switch SW3, the set gear number is set to a gear step number one lower than the current state, and the process proceeds to step S8. In step S7, the set speed is set to a speed that is one step higher than the current speed, and the process proceeds to step S8.

  In step S8, pressure reduction control of the pressure oil supplied to the main clutch 17 is performed to disengage the main clutch 17, and the process proceeds to step S9. In step S9, the main transmission 16 is shifted to the speed set in any of step S4, step S6 or step S7, and the process proceeds to step S10.

  In step S10, completion of shift switching of the main transmission 16 is detected. If completion is not detected, the process returns to step S10, and if completion is detected, the process proceeds to step S11. In step S11, pressure increase control of the pressure oil supplied to the main clutch 17 is performed to engage the main clutch, and the process returns to step S1. As described above, the shift control of the main transmission 16 by the control device 76 is performed.

Next, the configuration of the auxiliary transmission lever 12 will be described with reference to FIGS.
FIG. 7 is a side view of the left operation panel and the auxiliary transmission lever, and FIGS. 8 to 12 are a front view, a left side view, a right side view, a plan view, and a rear view of the grip portion. The auxiliary transmission lever 12 protrudes obliquely upward and forward from a left operation panel 97 provided on the left side of the seat 9, and swings by gripping a vertical grip portion 98 formed on the upper portion with the left hand of the operator. Supported to be able to.

  The grip portion 98 has a distal end portion (upper end portion) curved forward with respect to the proximal end portion, and an arcuate surface 98a is formed at the distal end portion. The circular arc surface 98a is formed in a substantially semi-circular shape that forms a mountain shape obliquely upward and forward in a side view so that the operator can place four fingers excluding the thumb with the palm placed. The neutral switch SW1 described above can be pushed and operated on the inner side surface (right side surface) of the grip portion 98, and the main transmission 16 is shifted on the inner side surface of the tip portion of the grip portion 98. A main transmission operating tool 99 is supported so as to be rotatable forward and backward.

  The main transmission operating tool 99 mainly includes a substantially circular main body 101 that follows the outer shape of the distal end portion of the side view grip portion 98 and a rear side of two protruding pieces that protrude outward from the side view main body 101. The shift-up switch SW2 provided in the grip portion 98 by a forward turning operation is composed of a thumb operating piece 102 that is a protruding piece and a food finger operating piece 103 that is a front protruding piece. The above-described shift down switch SW3 provided in the grip portion is operated to be pushed (decelerated) by a backward turning operation.

  The main body 101 is disposed on the inner side (lower side) in a side view with respect to the arcuate surface 98a, and is compactly fitted and supported on the inner side surface of the grip portion 98 so as to be rotatable back and forth. This prevents the operator from accidentally touching the main body 101 when holding the grip portion 98.

  FIG. 13 is a side view showing a state where the speed increasing operation is performed by the thumb operating piece of the main transmission operation tool, and FIG. 14 is a side view showing a state where the speed reduction operation is performed by the thumb operating piece of the main transmission operating tool. The thumb operating piece 102 is formed in a mountain shape that protrudes outward from the distal end portion of the side view grip portion 98. A planar speed increasing operation piece 102a that inclines upward toward the front is provided at the rear part of the thumb operating piece 102, and a planar speed reducing operation piece 102b that is inclined downward to the front is provided at the front part of the thumb operating piece 102. Is provided.

  The operator can perform the forward / backward rotation operation of the main transmission operating tool 99 with the thumb operation piece 102 in a state where the side peripheral surface of the grip portion 98 is gripped by the palm. Specifically, by placing the thumb on the speed increasing operation piece 102a of the thumb operating piece 102 and pushing it forward, the main transmission operating tool 99 is rotated forward while the thumb operating piece 102 is decelerated. The main transmission operating tool 99 is rotated backward by placing the thumb on the operation piece 102b and pulling it backward. As described above, since the operation location is divided between the case where the forward rotation operation is performed and the case where the backward rotation operation is performed, the operability of the main transmission operation tool 99 is improved. A stop 104 that slides on the speed increasing operation piece 102 a or the speed reducing operation piece 102 b may be provided to prevent the thumb from sliding from the thumb operating piece 102.

  FIG. 15 is a side view showing a state in which a speed change operation is performed with a finger operating piece of the main speed change operation tool. The finger operating piece 103 is formed in an arc shape that is located slightly outward from the tip of the side view grip portion 98 and conforms to the outer shape of the tip, and prevents slipping when the finger is placed on the surface. An anti-slip portion 104 is formed. The operator puts the palm on the arcuate surface 98a and grips the grip portion 98, and puts the finger on the finger operating piece 103 and pushes it downward to perform the forward rotation operation of the main transmission operating tool 99. Then, the main transmission operating tool 99 is rotated backward by operating it by pulling it upward. At this time, the anti-slip portion 104 can prevent the occupant from slipping from the occupant finger operation piece 103, so that the operability of the main transmission operation tool 99 is improved.

  The main transmission operating tool 99 configured as described above has high convenience and versatility because the finger that performs the forward and backward rotation operation can be selected in accordance with the operator's preference and situation.

  FIGS. 16 and 17 are a side sectional view and a back sectional view showing the structure inside the grip portion of the auxiliary transmission lever. The main transmission operating tool 99 is supported by the grip portion 98 so as to be pivotally supported by being fixed to a pivot shaft 106 that is rotatably supported in the grip portion 98. A cam plate 107, which swings back and forth as the main transmission operating tool 99 rotates, is fixed to the rotation shaft 106.

  The cam plate 107 swings backward when the main transmission operation tool 99 is rotated forward, and pushes the above-described shift-up switch SW2 provided in the grip portion 98, while the main transmission operation tool 99 moves backward. When it is turned, it is configured to swing forward and push the aforementioned downshift switch SW3 provided in the grip portion 98. Then, the process shown in FIG. 6 as described above is executed.

  The cam plate 107 is biased to a neutral position where the downshift switch SW2 and the upshift switch SW3 are not pushed by an elastic member such as a spring 108. For this reason, the main transmission operating tool 99 is also stopped at the neutral position unless the operator intentionally performs the forward / backward rotation operation.

  The example in which the thumb operating piece 102 of the main transmission operating tool 99 is divided into the speed increasing operating piece 102a and the speed reducing operating piece 102b has been described above, but FIGS. An example of a single operation piece is shown.

  18 to 22 are a front view, a left side view, a right side view, a plan view, and a rear view of a grip portion showing another embodiment, and FIG. 23 shows a state in which a speed change operation is performed by a thumb operating piece of a main speed change operation tool. FIG. The thumb operating piece 102 is formed in an arc shape along the outer shape of the distal end portion and is located slightly outward from the distal end portion of the side view grip portion 98, and slipping to prevent slipping when placing the thumb finger on the surface. A stop 104 is formed.

  The operator performs the forward rotation operation of the main transmission operating tool 99 by operating the gripper 98 with the thumb on the thumb operating piece 102 and pushing it forward while holding the side peripheral surface of the grip part 98 with the palm. The main transmission operating tool 99 is rotated backward by operating it by pulling backward. At this time, since the anti-slip portion 104 can prevent the thumb from slipping from the thumb operating piece 102, the operability of the main transmission operating tool 99 is configured.

  FIG. 24 is a side view showing a state in which a shifting operation is performed on the finger operating piece of the main transmission operating tool by the tip of the eating finger, and FIG. 25 is a side view showing a state in which the shifting operation of the eating finger operating piece of the main transmission operating tool is performed on the entire finger. It is. When the forward / backward turning operation of the main speed change operation tool 99 is performed with the finger, the tip portion of the finger can be placed on the finger operation piece 103 (see FIG. 24), while the entire finger is placed on the finger operation piece 103 and the main body 101. It is also possible to operate by placing it (see FIG. 25). For this reason, the main transmission operating tool 99 having the above-described configuration further improves convenience and versatility.

1 is an overall plan view of a tractor to which a shift operation tool for a work vehicle according to the present invention is applied. It is a power transmission system diagram of this tractor. It is a hydraulic circuit of a hydraulic control apparatus. It is a block diagram of a control apparatus. It is explanatory drawing which shows the transmission pattern of a main transmission. It is a flowchart of a control apparatus. It is a side view of a left operation panel and an auxiliary transmission lever. It is a front view of a grip part. It is a left view of a grip part. It is a right view of a grip part. It is a top view of a grip part. It is a rear view of a grip part. It is a side view which shows the state which carried out the speed increase operation with the thumb operation piece of the main transmission operation tool. It is a side view which shows the state which carried out deceleration operation with the thumb operation piece of the main transmission operation tool. It is a side view which shows the state which speed-change-operated with the eating finger operation piece of the main speed change operation tool. It is a side cross section which shows the structure in the grip part of an auxiliary transmission lever. It is a back sectional view showing the structure in the grip part of the auxiliary transmission lever It is a front view of the grip part which shows another Example. It is a left view of the grip part which shows another Example. It is a right view of the grip part which shows another Example. It is a top view of the grip part which shows another Example. It is a rear view of the grip part which shows another Example. FIG. 6 is a side view showing a state in which a speed change operation is performed by a finger operating piece of a main speed change operation tool. It is a side view which shows the state which carried out gear shifting operation of the eating finger operation piece of the main transmission operating tool with the eating finger tip part. It is a side view which shows the state which carried out gear shift operation of the cleaver operation piece of the main transmission operation tool with the whole lip.

Explanation of symbols

12 Sub-transmission lever 16 Main transmission (traveling main transmission)
19 Subtransmission (traveling subtransmission)
98 Grip part 99 Main transmission operation tool 102 Finger operating piece 103 Eating finger operating piece 102a Speed increasing operation piece 102b Deceleration operating piece 104 Non-slip part

Claims (3)

  A main transmission operating tool (99) for performing a shift operation of the traveling main transmission (16) by electric control is provided on a grip portion (98) of the auxiliary transmission lever (12) for performing a shifting operation of the traveling auxiliary transmission (19). In the shift operating tool of the working vehicle, the main shift operating tool (99) is supported on the side of the sub-shift lever (12) on the operator side so as to be able to rotate back and forth, and the operator can subseat the main shift operating tool (99). Shift operation of a work vehicle in which a thumb operating piece (102) for rotating with a thumb and a cleaver operating piece (103) for rotating with a forefinger is formed while gripping the grip (98) of the speed change lever (12). Ingredients.   The speed-up operation piece (102a) for speed-up operation with a thumb and the speed-down operation piece (102b) for speed-down operation with a thumb, and the thumb operation piece (102) of the main transmission operating tool (99) are configured. Gear shifting operation tool for work vehicles.   The speed change operation tool for a work vehicle according to claim 1 or 2, wherein a non-slip portion (104) is formed on the thumb operating piece (102) or the forefinger operation piece (103) of the main speed change operation tool (99).

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