JP2009154844A - Working vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable quick speed change operation without hindrance by rationally arranging speed change gears within a transmission case and also neutralizing a hydraulic speed change clutch. <P>SOLUTION: A working vehicle is constructed by arranging a forward-reverse switching clutch 2 hydraulically turned on and off, and a plurality of hydraulic speed change clutches 3, 4 and 8 on the upstream side of transmission of a multistage speed change gear 40 disposed within the transmission case 1; and disposing a clutch operation tool 59 for bringing the forward-reverse switching clutch 2 and these hydraulic speed change clutches 3, 4 and 8 into a neutral position during transmission of the speed change gear 40. The clutch operation tool 59 is constituted by a clutch switch 5 disposed on an operation lever 7 of the speed change gear 40. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a work vehicle such as a tractor or a passenger management machine.

  In a work vehicle such as a tractor, as described in Japanese Patent Application Laid-Open No. 2004-201622, a main clutch that interrupts power in a transmission case that transmits power from an engine to a traveling wheel, a shift clutch of a multi-stage transmission gear, or a front wheel A front wheel drive clutch that interrupts the power transmission is provided, and the rotation of the traveling wheels is finely increased / decreased so that the rotational output of the diesel engine used at a substantially constant rotation can travel at a speed according to the working conditions. Each clutch includes a hydraulic clutch and a synchromesh mechanism clutch.

In order to simplify the operation of switching the forward / reverse travel and the gear ratio switching by operating such a plurality of clutches, Japanese Patent Laid-Open No. 10-315792 discloses a forward / reverse transmission of a synchromesh mechanism from the front of transmission, The first sub-transmission of the hydraulic clutch mechanism, the main transmission of the synchromesh mechanism, and the second sub-transmission of the simple mechanical clutch mechanism are arranged in this order, and the forward / reverse transmission, the first sub-transmission, and the main transmission are hydraulically operated. The second subtransmission is configured to be shifted by lever operation by shifting the actuator.
JP 2004-201622 A Japanese Patent Laid-Open No. 10-315792

  The shifting of the traveling speed in the above-described conventional work vehicle is performed by changing the meshing of an appropriate transmission gear after the main clutch in the transmission case is operated, but the transmission gear is inertial force immediately after the main clutch is operated. In some cases, it is difficult to engage the speed change gear, that is, to change speed.

  Therefore, an object of the present invention is to make it possible to perform a speed change operation without any trouble by rationalizing the arrangement of the speed change gear in the mission case and by making the hydraulic speed change clutch neutral.

The above object of the present invention is achieved by the following configuration.
That is, according to the first aspect of the present invention, the forward / reverse switching clutch 2 and the plurality of hydraulic transmission clutches 3, 4, 8 that hydraulically enter and exit the transmission upstream side of the multiple-stage gear transmission 40 provided in the transmission case 1 are provided. A work vehicle is provided which is provided with a clutch operating tool 5 for setting the forward / reverse switching clutch 2 and the plurality of hydraulic transmission clutches 3, 4, 8 to a neutral position when the gear transmission 40 is shifted.

  In this configuration, when the clutch operating tool 5 is operated to disengage the clutch, the forward / reverse switching clutch 2 and the clutches of the plurality of hydraulic transmission clutches 3, 4, 8 are neutral, and the driving force from the engine is immediately cut off. Thus, the gear transmission of the gear transmission 40 can be quickly performed without any trouble.

  The invention according to claim 2 is the work vehicle according to claim 1, wherein the clutch operating tool 5 is constituted by a clutch switch 5 provided on the operation lever 7 of the gear transmission 40.

  With this configuration, gear shifting can be performed while operating the clutch switch 5 with a hand holding the operation lever 7 of the gear transmission 40.

  According to the first aspect of the present invention, there is no need for a main clutch that only interrupts the power transmission, and the gear transmission is configured to disconnect the power transmission by neutralizing the forward / reverse switching clutch 2 and the plurality of hydraulic transmission clutches 3, 4, 8. Thus, the transmission mechanism in the transmission case 1 can be simplified, and the gear transmission 40 can be shifted quickly and smoothly.

  According to the second aspect of the present invention, the speed change operation of the gear transmission 40 can be performed with only one hand holding the operation lever 7 of the gear transmission 40 without depressing the clutch pedal.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a drive force transmission mechanism, and shows a power transmission configuration from the engine 14 to the front wheels 89, the rear wheels 58, the PTO drive shaft 113, and the hydraulic pump 10.

  A gear 16 is fixed to the input shaft 15 directly connected to the output shaft of the engine 14 and the forward / reverse switching clutch 2 is mounted. The gear 16 meshes with a gear 92 fixed to the first counter shaft 91, meshes with another gear 93 fixed to the first counter shaft 91, and this gear 94 is fixed to the input shaft 96 of the hydraulic pump 10. The hydraulic pump 10 is always driven by meshing with the gear 95. A power steering hydraulic pump 133 is provided adjacent to the hydraulic pump 10 and is driven by a coaxial 96.

  One gear 17 of the forward / reverse switching clutch 2 meshes with a gear 19 fixed to the first transmission shaft 18 and decelerates, and the other gear 20 of the forward / reverse switching clutch 2 is connected to the first transmission shaft 18 via a counter gear 22. The power is transmitted in reverse by meshing with the fixed gear 23. That is, when the forward / reverse switching clutch 2 is placed (connected) to the gear 17 side, the rotation of the input shaft 15 is transmitted to the first transmission shaft 18 in the reverse direction, and when it is placed on the gear 20 side, the rotation of the input shaft 15 is forward. The main clutch disengaged state can be maintained by controlling the hydraulic valve, which will be described later, in the main clutch disengaged state in which the neutral state away from both the gear 17 and the gear 20 is disengaged from the power transmission. I am doing so.

  The first transmission shaft 18 has a first transmission clutch 3 for a first speed / three-speed switching operation and a second speed / four-speed switching operation, which are shifted by a main transmission lever provided in a driver's seat on the lower transmission side of the forward / reverse switching clutch 2. The second transmission clutch 4 is attached. That is, the gears 25 and 27 of the first transmission clutch 3 mesh with the gears 26 and 28 fixed to the second counter shaft 24, and the first transmission shaft 18 is decelerated for the first speed or slightly increased for the third speed. Is transmitted to the second counter shaft 24. Further, the gears 29 and 31 of the second speed change clutch 4 are engaged with the gears 30 and 32 fixed to the second countershaft 24, and are slightly increased for the second speed or greatly increased for the fourth speed. The rotation of the transmission shaft 18 is transmitted to the second counter shaft 24.

  A third counter shaft 34 is connected to the lower transmission side of the second counter shaft 24 by a coupling 33 to transmit the rotation as it is. A small gear 35 and a large gear 36 are fixed to the third counter shaft 34.

  The small gear 35 and the large gear 36 mesh with the large gear 38 and the small gear 39 of the high / low speed switching clutch 8 mounted on the second transmission shaft 37, respectively, and the third counter shaft 34 rotates at a high speed or a low speed at the second transmission shaft. 37. The high / low speed switching clutch 8 is switched by a high / low switching lever provided in the driver's seat.

A gear 42 is fixed to the lower transmission side end portion of the second transmission shaft 37, and the gear 42 and a large gear 44 of a large and small gear 59 pivotally supported on the third drive shaft 49 are engaged with each other to reduce the transmission. Yes.
The small gear 45 of the large and small gear 59 meshes with the gear 43 of the double sub-transmission clutch 40 with a synchro mechanism that is pivotally supported by the bevel gear shaft 48, and is transmitted at a reduced speed. Further, the gear 47 provided integrally with the gear 43 is engaged with the large gear 50 fixed to the fifth countershaft 120 for transmission at a reduced speed.

  A small gear 51 is further fixed to the fifth counter shaft 120, and the small gear 51 is engaged with the large gear 46 of the double sub-transmission clutch 40 to be further decelerated. Therefore, the rotation of the second transmission shaft 37 is transmitted while being sequentially decelerated in the order of gear 42 → large gear 44 → small gear 45 → gear 43 → gear 47 → large gear 50 → small gear 51 → gear 46.

  The shifters 121 and 122 of the double auxiliary transmission clutch 40 are slidably engaged with the bevel gear shaft 48 in the axial direction. When the shifter 121 is slid to the gear 43 side and engaged, the rotation of the gear 43 remains at a high speed. When the shifter 122 slides to the gear 47 side and engages with the bevel gear shaft 48, the rotation of the gear 47 is transmitted to the bevel gear shaft 48 at a medium speed, and when the shifter 122 slides to engage with the gear 48 side and rotates, the gear 47 rotates. Is transmitted to the bevel gear shaft 48 at a low speed, and is gradually decelerated to rotate the bevel gear shaft 48.

  The shifters 121 and 122 of the double auxiliary transmission clutch 40 are operated by the auxiliary transmission lever 7 provided in the driver's seat. In order to change the gear combination, the rotation of the drive shaft must be slowed down or stopped completely. However, the control is performed by a traveling system controller 135 incorporating a microcomputer as described later. As shown in FIG. 7, the auxiliary transmission lever 7 tilts the auxiliary transmission lever 7 back and forth to move the shifters 121, 122 to shift to high, medium, and low, and the clutch switch 5 and the speed increase at the grip 9. A switch 11 and a deceleration switch 13 are provided.

The rotation of the bevel gear shaft 48 is transmitted to the differential gear 123 via the bevel gears 54 and 55, and is transmitted from the differential gear 123 to the rear wheel 58 via the axle 56 and the planetary gear 57.
To summarize the above description, the rotation of the input shaft 15 is first switched to forward rotation or reverse rotation by the forward / reverse switching clutch 2, and the first speed / three-speed switching first transmission clutch 3 and the second / fourth-speed switching second clutch. The gear shift clutch 4 shifts to four speeds, the high / low speed switching clutch 8 shifts to two speeds, the double sub-shift clutch 40 shifts to three speeds, and is transmitted to the bevel gear shaft 48. That is, the rotation of the input shaft 15 is shifted to 4 × 2 × 3 = 24 speeds and transmitted to the axle 56.

  At the time of shifting the double sub-shifting clutch 40, the clutch switch 5 of the sub-shifting lever 7 is pushed to move the forward / reverse switching clutch 2, the first speed / three-speed switching first shift clutch 3, and the second / fourth speed switching. Either the second shifting clutch 4 or the high / low speed switching clutch 8 is neutral at the same time. However, when the clutch is connected, there is much wear on the clutch that is connected last. Yes.

  Transmission to the front wheel 89 is performed as follows. A gear 53 is fixed to the bevel gear shaft 48, and the gear 53 is meshed with a gear 52 fixed to the third drive shaft 49 to drive the third drive shaft 49. Another gear 68 fixed to the third drive shaft 49 is meshed with a gear 69 of a front wheel acceleration clutch 70 attached to a transmission shaft 67 connected to the front wheel drive shaft 76 by a coupling 75. The gears 126 and 74 of the front wheel acceleration clutch 70 and the all-wheel drive clutch 156 are engaged with gears 72 and 73 fixed to the seventh countershaft 71, so that the front wheel acceleration and the rear wheel drive (two-wheel drive) ).

  A gear 77 is fixed to the front wheel drive shaft 76 and is engaged with a gear 78 fixed to the front wheel drive bevel shaft 127 to transmit power. The power of the front wheel drive bevel shaft 127 drives the front wheels 89 via the bevel gears 79 and 80, the differential gear 81, the bevel gears 82 and 83, the vertical shaft 84, the bevel gears 85 and 86, and the planetary gear 88.

Next, the power transmission of the PTO drive shaft 113 will be described.
The gear 16 of the input shaft 15 is engaged with the gear 101 of the PTO intermittent clutch 100 mounted on the fourth counter shaft 102, and two gears 103 and 104 are fixed to the fourth counter shaft 102.

  A first PTO shaft 107, a second PTO shaft 66, and a third PTO shaft 109 are arranged in series with respect to the input shaft 15 at a position symmetrical to the input shaft 96 of the hydraulic pump 10, and the first PTO shaft on the uppermost transmission side is arranged. One side of the drive switching clutch 67 mounted on the second PTO shaft 66 at high speed or low speed by the gears 105 and 106 of the high and low clutch 12 mounted on the PTO shaft 107 meshing with the gears 103 and 104 and sliding the shifter, respectively. The disk 114 is driven.

  The other disk 115 of the drive switching clutch 67 meshes with a gear 64 fixed to the sixth countershaft 62 with a gear 65 integrated with the other disk 115. The sixth counter shaft 62 is transmitted by meshing the gear 61 fixed to the ground shaft 60 connected to the third drive shaft 49 with the coupling 116 with the gear 63 fixed to the sixth counter shaft 62. The power from the bevel gear shaft 48 that drives the rear wheel 58 is transmitted to the other disk 115.

  Therefore, when the shifter 117 of the drive switching clutch 67 is slid to the one-side disk 114, the power of the first PTO shaft 107 is transmitted, and when the shifter 117 is slid to the other-side disk 115, the power from the ground shaft 60 is transmitted.

  The second PTO shaft 66 to which the drive switching clutch 67 is attached is connected to the third PTO shaft 109 by the coupling 108, and the shaft of the gear 111 is connected to the third PTO shaft 109 by the coupling 110. The PTO drive shaft 113 is driven by meshing with the gear 112 fixed to the PTO drive shaft 113.

  FIG. 2 is a power transmission diagram in which the periphery of the drive switching clutch 67 is changed. The long ground shaft 60 is changed to the short eighth counter shaft 118, and the power transmission from the bevel gear shaft 48 is cut off. Then, the gear 119 fixed to the eighth counter shaft 118 is engaged with the gear 97 fixed to the one-side disk 114 and the gear 98 fixed to the sixth counter shaft 62, and further fixed to the eighth counter shaft 118. The other disk 115 is reversely rotated by meshing another gear 99 with the gear 65 integrated with the other disk 115. Accordingly, when the shifter 117 of the drive switching clutch 67 is slid to the one-side disk 114, the power of the first PTO shaft 107 is transmitted in the normal direction, and when the shifter 117 is slid to the other-side disk 115, the power of the first PTO shaft 107 is reversed. Will be transmitted at high speed. Therefore, by controlling the engine rotation from 2000 rpm to 1700 rpm, for example, in order to prevent reverse high-speed rotation, the normal PTO shaft rotation is performed at a low engine speed, thereby reducing fuel consumption. Become a shift.

  FIG. 3 is a side sectional view of the transmission case 1 that constitutes the transmission diagram of FIG. 1. The transmission case 1 is configured by connecting the front transmission case 1a, the intermediate transmission case 1b, and the hollow case of the rear transmission case 1c. ing. Inside the front mission case 1a, the forward / reverse switching clutch 2, the PTO intermittent clutch 100, the PTO high / low speed switching clutch 12, and the drive switching clutch 67 are built in, and the hydraulic pump 10 is mounted outside the case. Inside the intermediate transmission case 1b, a first speed / three-speed switching first shift clutch 3, a second / fourth speed switching second shift clutch 4, a high / low speed switching clutch 8 and a front wheel speed increasing clutch 70 are incorporated. ing. The rear transmission case 1c integrally constitutes a differential gear case, and a double sub-transmission clutch 40 and a PTO high / low speed clutch 12 are incorporated therein.

  4 is a side sectional view of the transmission case 1 that constitutes the transmission diagram of FIG. 2. The difference from FIG. 3 is that an eighth counter shaft 118 is installed instead of the long ground shaft 60. The drive switching clutch 67 functions as an economy shift by changing and adding gears.

  FIG. 5 is an enlarged view of the transmission device in the transmission case 1, and is an enlarged view of a plurality of gear transmissions 40 and their surroundings. The multi-stage gear transmission 40 is a low-speed, medium-speed, and high-speed three-speed shift, and the medium-speed and high-speed are synchronized. Low speed is assumed to be a gear dock connection.

  As shown in FIG. 6, the tractor equipped with the transmission mechanism and the hydraulic circuit has an engine 14 mounted inside the hood 125 at the front of the vehicle body, and transmits the rotational power of the engine 14 to the transmission mechanism in the transmission case 1. The rotational power appropriately decelerated is transmitted to the left and right front wheels 89 and the left and right rear wheels 58.

  A steering handle 126 for steering the left and right front wheels 89 and 89 is provided behind the engine 14, and a cockpit 127 is installed behind the steering handle 126. A cylinder case 128 is mounted on the rear upper part of the transmission case 1, and left and right lift arms 129 and 129 are pivotally supported on both left and right sides of the cylinder case 128. When the working oil is supplied to the hydraulic cylinder for raising and lowering the work implement housed in the cylinder case 128, the lift arms 129 and 129 are configured to rotate upward. Various work machines R can be connected to the three-point link mechanism of the lower link 130, 130 and the top link 131 connected to the lift arms 129, 129. Although not shown in the figure, a clutch pedal for interrupting power is provided at the feet of the cockpit 127.

Next, various automatic controls by the microcomputer will be described.
FIG. 8 is a block diagram showing input / output of control signals. A travel system controller 135 that controls the travel speed, an engine controller 163 that controls the output of the engine 14, and a work machine lift system controller 171 that controls the lift of the work machine. It is connected with a communication line and communicates control signals.

  First, the running system controller 135 receives on / off information of each clutch of the first speed / third speed switching first transmission clutch 3 and the second speed / fourth speed switching second transmission clutch 4 from the transmission 1 clutch pressure sensor 136. The shift 2 clutch pressure sensor 137, the shift 3 clutch pressure sensor 138 and the shift 4 clutch pressure sensor 139 are input, and the on / off information of the high / low speed switching clutch 8 is input from the Hi clutch pressure sensor 140 and the Lo clutch pressure sensor 141. On / off information of the forward / reverse switching clutch 2 is input from the forward clutch pressure sensor 142 and the reverse clutch pressure sensor 143, and the forward / reverse lever operating position for detecting the shift position of the forward / reverse lever for shifting the forward / reverse switching clutch 2 is detected. The shift position from the sub shift lever operation position sensor 145 that detects the shift position of the sensor 144 and the double sub shift clutch 40. Broadcast is input to the traveling system controller 135.

  Furthermore, the travel system controller 135 receives a travel speed from a vehicle speed sensor 146 that detects the number of revolutions of the rear wheel 58, and an oil temperature in the mission case 1 is input from the mission oil oil temperature sensor 147. The position of the clutch pedal is input from the sensor 148, and the engine power setting information is input from the engine power selection switch 149.

  Further, the accelerator shift information is input from the accelerator shift setting switch 151, the setting information is input from the main shift acceleration / deceleration operation switch 151, and the accelerator setting information is input from the accelerator sensor 152 to the traveling system controller 135, and the accelerator fine adjustment is performed. Setting information is input from the lever 153, and output torque line setting information of the engine is input from the torque selection switch 134. The accelerator fine adjustment lever 153 is a rebound push switch, and the adjustment value changes step by step each time it is pressed.

  The control signal output from the travel system controller 135 includes a switching signal to the forward / reverse switching solenoid 154 of the hydraulic valve that operates the forward / reverse switching clutch 2, a switching boost signal to the linear boost solenoid 155, and a neutral operation to the clutch solenoid 156. Signal, a switching signal to the shift 1-3 switching solenoid 157 and a boost signal to the shifting 1-3 boost solenoid 158 of the hydraulic valve that operates the first speed / three-speed switching first shift clutch 3, a second speed / fourth speed switching. The switching signal to the shift 2-4 switching solenoid 159 of the hydraulic valve that operates the second speed change clutch 4 and the boost signal to the shift 2-4 boost solenoid 160, the Hi clutch of the hydraulic valve that operates the high / low speed switching clutch 8 This is a high / low switching signal to the switching solenoid 161 and the Lo clutch switching solenoid 162.

  The information signal input to the engine controller 163 includes the exhaust temperature from the engine exhaust temperature sensor 164, the rotational speed from the engine rotation sensor 165, the oil pressure from the engine oil pressure sensor 166, and the cooling from the engine water temperature sensor 167. The control signal output from the engine controller 163 at the water temperature and the common rail pressure from the rail pressure sensor 168 is a pressurization signal to the fuel high pressure pump 169 and a fuel injection signal to each high pressure injector 170.

  The information signal input to the work implement lifting system controller 171 is arm position information from the lift arm sensor 172, and the control signal output from the work implement lifting system controller 171 is a hydraulic cylinder that operates the left and right lift arms 129 and 129. It is a raising / lowering signal to the main raising solenoid 173 and the main lowering solenoid 174 of the main valve.

The meter panel 175 displays detection information of each sensor and switch setting information, and various setting signals are input through the operation panel 176.
FIG. 9 is a flowchart of automatic control at the time of shifting of the double sub-shift clutch 40. In step S1, it is determined whether the clutch pedal provided at the foot of the driver's seat is depressed (ON). If NO, the sub-shift is performed in step S2. If it is determined that the clutch switch 5 provided on the lever 7 is ON and the determination in step S2 is YES or the clutch pedal is ON in step S1, the forward / reverse switching clutch 2 and the first speed / three-speed switching first shift are determined in step S3. All the hydraulic clutches of the clutch 3, the second speed / fourth speed switching second shift clutch 4 and the high / low speed switching clutch 8 are made neutral so that the rotation of the engine 14 is not transmitted to the double subtransmission clutch 40.

  Further, when the shift of the double sub-transmission clutch 40 is a shift from a high speed to a medium speed in step S5, the first speed clutch 3 for switching the first speed / three speed and the second speed / fourth speed switching clutch 3 in step S5. The two-speed clutch 4 is engaged at a low pressure to cause double engagement and completely stop the transmission shaft from rotating.

FIG. 10 is a plan view of the work machine control adjustment panel 180.
On the front side of the work implement control adjustment panel 180, an accelerator memory 179 that stores two types of rotation speed of the engine 14, a position control lever 181 that moves the work implement up and down, and a tillage depth adjustment that adjusts the tillage depth of the rotary tiller. A dial 182 is provided, an elevating control unit 200 and an automatic control setting unit 201 for controlling elevating of the left and right lift arms 129 and 129 are provided at the center, and an automatic control adjusting unit 202 and a horizontal control adjusting unit 203 are provided on the rear side. .

  The elevation control unit 200 is provided with an automatic control sensitivity standard input button 204, an automatic control type display unit 183, an automatic control switching button 205, a lowered position adjustment dial 184, and a lowering speed adjustment dial 185. Each time the automatic control switching button 205 is pressed, the auto rotary, mix auto, load auto, and draft lamps of the automatic control type display unit 183 are lit and the control is switched. For example, when autorotation is used, automatic horizontal control and backup control are performed.

  The automatic control setting unit 201 is provided with an auto accelerator button 186, an auto lift button 187, a backup button 188, and an auto brake button 189. The automatic control adjustment unit 202 includes a PTO intermittent automatic sensitivity button 190, a sensitivity adjustment button 191, a PTO connection button 192, a speed change connection button 193, a linear connection button 194, and a brake weakening button 195.

  The horizontal control unit 203 is provided with a horizontal sensitivity button 196, a horizontal switching button 197 for switching between tilt, parallel, manual, and automatic horizontal, a horizontal tilt adjustment dial 198, and a horizontal switch button 199 for setting the degree of tilt. For example, when the horizontal switch button 197 is manually set and the rotary tiller is tilted to the left and right with the left and right tilt adjustment dial 198 and then automatically switched again with the horizontal switch button 197, the rotary tiller is controlled to maintain the tilted state. This control is performed by adding / subtracting the correction value to the left / right sensor output values for detecting the left / right height of the rotary tiller by the work machine lifting / lowering system controller 171.

  In addition to the above, the work implement elevating system controller 171 may be provided with a control capable of setting multi-work. However, if the controller equipped with this control is shared with a truck or the like not equipped with automatic multi-control, the control panel 171 Do not display auto multi.

FIGS. 11 and 12 are control flowchart diagrams of the adjustment buttons and the adjustment dial provided on the work implement control adjustment panel 180. FIG.
In step S9, the detection value of each sensor and the setting value of each operation switch are read, and if the sensitivity adjustment button 191 is being operated for a long time in step S10, the linear connection is made in step S11 from the PTO connection button 192 or the speed change connection button 193. Press one of the buttons 194 or the brake weakening button 195 to display the sensitivity of the selected control target. If you press increase with the sensitivity adjustment button 191 in step S12, the sensitivity is increased by one rank in step S13, and if you press decrease, the sensitivity is increased. If one rank is decreased and neither increase nor decrease is pressed, the current sensitivity is set as control data in step S14. In step S16, the adjusted sensitivity is displayed on the display unit. If the sensitivity adjustment button 191 is not being pressed for a long time in step S10, the process proceeds to step S17.

  If the PTO connection button 192 is turned on for a short time in step S17, it is determined in step S18 whether the PTO sensitivity immediately before the operation is standard. If YES, the PTO sensitivity switching monitor is turned off in step S19 and the PTO sensitivity is turned off. The connection sensitivity is set to the standard value. If NO, the PTO sensitivity switching monitor is turned on in step S20, the PTO sensitivity is set to the fine adjustment stored value, and the adjustment LED display is changed to the PTO fine adjustment state display. If the PTO connection button 192 is not turned on for a short time in step S17, these processes are skipped and the process proceeds to the next step S21.

  If the linear connection button 194 is turned on for a short time in step S21, it is determined in step S22 whether the linear shift sensitivity immediately before the operation is standard. If YES, the linear shift sensitivity switching monitor is turned off in step S23. The linear shift sensitivity is set to the standard value. If NO, the linear shift sensitivity switching monitor is turned on in step S24, the PTO connection sensitivity is set to the fine adjustment stored value, and the adjustment LED display is changed to the linear shift fine adjustment state display. . If the linear connection button 194 is not turned on for a short time in step S21, these processes are skipped and the process proceeds to the next step S25.

  If the shift connection button 193 is turned on for a short time in step S25, it is determined in step S26 whether the shift sensitivity immediately before the operation is standard. If YES, the shift sensitivity switching monitor is turned off in step S27 and the shift is performed. If the sensitivity is set to the standard value, if NO, the shift sensitivity switching monitor is turned on in step S28, the shift sensitivity is set to the fine adjustment stored value, and the adjustment LED display is changed to the shift fine adjustment state display. If there is no short time ON operation of the speed change connection button 193 in step S25, these processes are skipped and the process proceeds to the next step S29.

  If the horizontal sensitivity button 196 is turned on for a short time in step S29, it is determined in step S30 whether the horizontal sensitivity immediately before the operation is standard. If YES, the horizontal sensitivity switching monitor is turned off in step S31 and the horizontal sensitivity is turned off. If the sensitivity is set to the standard value, if NO, the horizontal sensitivity switching monitor is turned on in step S32, the horizontal sensitivity is set to the fine adjustment stored value, and the adjustment LED display is set to the horizontal fine adjustment state display. If the horizontal sensitivity button 196 is not turned on for a short time in step S29, these processes are skipped and the process proceeds to the next step S33.

  If there is a short-time ON operation of the automatic control switching button 205 in step S33, it is determined in step S34 whether the lift mode is auto-rotary. If YES, the auto-rotary sensitivity immediately before the operation is standard in step S35. If YES, the auto rotary sensitivity switching monitor is turned off in step S36 and the auto rotary sensitivity is set to the standard value. If NO, the auto rotary sensitivity switching monitor is turned on in step S37 and the auto rotary sensitivity is set. Set the sensitivity to the fine adjustment memory value and set the adjustment LED display to the auto rotary fine adjustment state display. If there is no short-time ON operation of the automatic control switching button 205 in step S34, these processes are skipped and the process returns.

  In step S33, it is determined whether the lift mode is load auto. If YES, it is determined in step S35 whether the load auto sensitivity immediately before the operation is standard. If YES, load auto sensitivity is switched in step S40. The monitor is turned off and the load auto sensitivity is set to the standard value. If NO, the load auto sensitivity switching monitor is turned on in step S41, the load auto sensitivity is set to the fine adjustment memory value, and the adjustment LED display is adjusted to the load auto fine adjustment. Display status. If the determination is NO in step S38, these processes are skipped and the process proceeds to the next step S42.

  In step S42, it is determined whether the lift mode is a draft. If YES, it is determined in step S43 whether the draft sensitivity immediately before the operation is standard. If YES, the draft sensitivity switching monitor is turned off in step S44. Then, the draft sensitivity is set to the standard value. If NO, the draft sensitivity switching monitor is turned on in step S45, the draft sensitivity is set to the fine adjustment stored value, and the adjustment LED display is changed to the draft fine adjustment state display. If the determination is NO in step S42, these processes are skipped and the process returns.

In the above description, sensitivity refers to the rate of pressure increase per hour in hydraulic pressure switching, and switching is quick when the sensitivity is high, and switching takes time when the sensitivity is low.
FIG. 13 is an output control flowchart of the engine 14, and FIG. 14 is an engine output chart.

  In step S50, information signals of the sensors and operation switches are read. In step S51, control signals and the like of the travel system controller 135 and work implement lifting system controller 171 are read. In step S52, control data of the engine controller 163 is read. Then, the engine speed is set according to the instruction from the accelerator sensor 153 by the accelerator lever or the accelerator pedal.

  In the next step S54, it is determined whether or not the accelerator fine adjustment lever 153 is operated. If there is, the instruction engine speed is changed in step S55 according to the operation direction and operation time of the accelerator fine adjustment lever 153. The change range is a maximum of ± 300 rpm. If there is no operation, step S55 is passed. Although not shown, if the engine speed instruction is given from the accelerator sensor 153 by the accelerator lever or the accelerator pedal after the instruction engine speed is changed, the engine speed is immediately changed.

  If YES in the next step S56 during the rotation instruction change, it is determined in step S57 whether the instruction rotational speed of the accelerator sensor 152 has changed beyond the current instruction rotational speed. If YES, the engine is determined in step S58. The rotation speed instruction is changed to the instruction rotation speed of the accelerator sensor 152. Then, the process proceeds to the next step S59. Even if the determination in step S56 or step S57 is NO, the process proceeds to the next step S59.

  In step S59, it is determined whether the torque lines A, B, and C shown in FIG. 14 are being selected. If NO, the presence / absence of operation of the torque selection switch 134 is determined in step S60. The standard torque line control is automatically performed in accordance with the acceleration speed indicated by the accelerator sensor. In the standard torque line control, the A line is selected when the indicated rotational speed is 2000 rpm or less, the B line is selected at 2200 rpm or higher, and the C line is selected when the command rotational speed is higher than 2200 rpm. If the determination in step S59 or step S60 is YES, control is performed using the torque line manually set in step S62.

  FIG. 14 is an output chart based on engine output control. There are a low rotation high torque A line, a medium rotation high torque B line, and a high rotation high torque C line. The engine output includes a standard H line and a high rotation. There are L lines where the output is averaged in the region. The A line, B line, and C line of the torque have the same output torque at the minimum rotation speed and the maximum rotation speed, and the output torque at the minimum rotation speed is larger than the output torque at the maximum rotation speed. Further, the output of the engine output H line and L line decreases at the maximum rotational speed.

It is a power transmission diagram in a mission case. It is a power transmission diagram in the mission case which changed a part. FIG. 2 is a longitudinal sectional view of the mission case in FIG. 1. FIG. 3 is a longitudinal sectional view of the mission case of FIG. 2. Enlarged view of part of the mission case It is the whole tractor side view. It is a partial enlarged side view. It is a control block diagram. It is a control flowchart figure of a clutch. It is a top view of the operation panel of a working machine. It is a control flowchart figure of a working machine. It is the whole tractor side view. It is a control flowchart figure of an engine. It is a performance curve figure of an engine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mission case 2 Forward / reverse switching clutch 3 Hydraulic transmission clutch 4 Hydraulic transmission clutch 8 Hydraulic transmission clutch 5 Clutch operating tool (clutch switch)
7 Operation lever 40 Gear transmission

Claims (2)

  A forward / reverse switching clutch (2) and a plurality of hydraulic transmission clutches (3), (4), (8) that are hydraulically engaged and disengaged upstream of the transmission of a multi-stage gear transmission (40) provided in the transmission case (1). And a clutch operating tool (5) for setting the forward / reverse switching clutch (2) and the plurality of hydraulic transmission clutches (3), (4), (8) to a neutral position when shifting the gear transmission (40). Work vehicle that is provided with.   The work vehicle according to claim 1, wherein the clutch operating tool (59) comprises a clutch switch (5) provided on an operation lever (7) of the gear transmission (40).

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