JP2008301830A - Agricultural tractor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To free an operator of complex operation for various settings in the turning operation of an agricultural tractor. <P>SOLUTION: The agricultural tractor is equipped with a work machine lift 25 for lifting a rotary work machine R, a work machine lift-controlling means C1 for controlling the work machine lift 25, a front wheel drive-switching device 3 for switching the vehicle body to the two-wheel drive mode or to the four-wheel drive mode, a running controlling means C2 for controlling the switch condition of the front-wheel drive-switching means 3, and a setting device 9 for switching the setting position to the running position P1 or the cultivation position P4. At the cultivation position P4, the running mode of the vehicle body is set to the four-wheel running mode and, and the work machine lift is turned on. The tractor is further provided with a setting tool for allowing individual and independent selection of front wheel acceleration control, automatic lift control and automatic braking control, and when the setting tool 9 is operated to the cultivation position P4, the front wheel acceleration control, the automatic lift control or automatic-braking control is forcedly turned on by the setting tool. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an agricultural tractor, and relates to the configuration of a setting device for various controls mounted on the tractor.

  In conventional agricultural tractors, so-called “backup control” that detects the reverse operation of the operator and raises the working machine connected to the vehicle body from the working position to the non-working position, or detects the turning state of the vehicle, A device having so-called “auto lift control” for raising the working position to the non-working position is known.

  In addition, the agricultural tractor is driven by driving the front and rear wheels of the vehicle in the “two-wheel drive” state and the “four-wheel drive” state, and the front wheel peripheral speed is increased relative to the rear wheel peripheral speed. A front / rear wheel drive switching device for switching to the "front wheel speed-up 4WD" state is provided, and the drive mode of the front and rear wheels is always set to the "2WD" state at the first setting position, and always set to the "4WD" state. Two setting positions, which can be set by a dial type setting tool arranged in order of the third setting position that shifts to the "front wheel acceleration 4WD" state when turning the vehicle from the "2WD" state or "4WD" state Things are also known.

The agricultural tractor is equipped with two turning controls such as a so-called “front wheel speed increasing control” for making the front wheel speed increasing 4WD when turning, and “auto brake control” for braking the rear wheel inside the turning, In the case where safety is important, either one of the two controls is selectively activated. On the other hand, in the case where operability is important, both control devices are controlled by a dial setting device. A configuration is known in which the setting operation of the operator is reduced by turning on and off at the same time.
JP 2001-146119 (paragraph [0035], [FIG. 1]) JP 4-19235 ([FIG. 2], [FIG. 3])

  As described above, agricultural tractors are equipped with a large number of controls according to the type of work and work conditions, but if these controls become excessive, the on / off setting of each control becomes troublesome or the setting is incorrect. This causes a problem that the safety is impaired.

  Further, in the usage pattern of the tractor, although there is a common usage pattern generally used by most users, as described above, a plurality of controls can be performed alternatively or simultaneously with the dial type setting tool. When the on / off setting is made, either the safety of the vehicle or the operability is impaired.

In view of the above-described problems, the present invention has a tractor control setting device configured as follows.
That is, a work implement elevating device (25) that elevates the rotary work implement (R) to a working position and a non-working position, a work implement elevating control means (C1) for controlling the work implement elevating device (25), and a front wheel ( 2F) a front-wheel drive switching device (3) for switching the driving mode of the vehicle body to the “two-wheel drive” state or the “four-wheel-drive” state by switching the driving mode to the non-driving state or the driving state, and the front wheel driving switching device (3) Is provided with a travel control means (C2) for controlling the switching state, and a setting device (9) for switching the set position between the travel position (P1) and the tillage position (P4) is provided. In the travel position (P1), the vehicle body The traveling mode is set to “2WD” and the work implement lifting control is set to OFF. At the tillage position (P4), the vehicle traveling mode is set to “4WD” and the work implement lifting control is turned on. Setting In the agricultural tractor, there is provided a setting tool capable of independently selecting front wheel acceleration control, auto lift control or auto brake control, and when the setting device (9) is operated to the tillage position (P4), The agricultural tractor is characterized in that the front wheel acceleration control, auto lift control, or auto brake control selected and set by the setting tool is forcibly turned on.

  With the above configuration, when the setting device (9) is set to the traveling position (P1), the vehicle body is always in the “two-wheel drive” state, and when set to the tilling position (P4), the vehicle body is in the “four-wheel drive” state. As well as being set, the control of the work implement lifting apparatus suitable for the tilling work is set on the entry side. In addition, when set to the tillage position (P4), turning control such as front wheel acceleration control, auto lift control, and auto brake control is forcibly turned on. Speed control, auto lift control or auto brake control can be turned on / off independently.

  In the present invention, the setting position of the setting device (9) is assumed to be the driving position (P1), the setting position assuming traveling on the road, the tilling work setting position used by most users as the tilling position (P4), and the work equipment tilling At the time of work, simply by operating the setting device (9), it is possible to easily set control suitable for tillage work or traveling, and at the tillage position (P4), turning control is forcibly turned on and during the tillage work. Since the turning operation can be facilitated and these turning controls can be turned on and off independently, it is possible to achieve an operation state according to the preference of the operator.

The present invention will be described below with reference to the drawings.
First, the overall configuration of the tractor 10 will be described.
As shown in FIG. 3, the tractor 10 includes a diesel engine E inside a bonnet 11, and the rotational power of the engine E is appropriately decelerated by various transmissions in the transmission case 13, and then the left and right rear wheels 2 </ b> R serving as a traveling device. Or, it is configured to travel by transmitting to the left and right front and rear wheels 2F, 2R.

  Further, a steering handle 16 that steers the front wheel 2F is provided in front of the cockpit 20 of the tractor 10, and an elevator lever 14 that moves the work implement up and down by one-touch operation up and down, before and after switching the vehicle forward and backward. An advance switch lever (not shown) and an accelerator lever 19 for adjusting the rotational speed of the engine E are provided. A forward switch 18f and a reverse switch 18r for detecting an operator's forward / backward operation and a neutral position operation are provided at the rotation base of the forward / reverse switching lever, and the rotation base of the accelerator lever 19 is made of a friction material. A lever holding mechanism is provided and connected to the governor mechanism G on the side of the engine E via a wire or the like. Further, a front wheel turning angle sensor 6 is provided as a means for detecting a turning operation of the vehicle at an interlocking portion of the steering handle 16, specifically, a pitman arm of the front wheel 2F.

  Further, as shown in FIG. 4, a meter panel controller C4 is provided on the back side in front of the steering handle 16, and various pilot lamps L1, L2I, an engine tachometer 75, a liquid crystal display M, etc. are provided on the front side. It is the structure which provides the meter panel 17 provided with. Also, below the meter panel 17, as shown in FIG. 1, a PTO on / off switch for turning on / off the rotation of a work switching dial 9 which is a dial type setting tool of the present invention and a PTO shaft 15 protruding from the rear of the vehicle body. 22a, an independent PTO control on / off switch 22b is provided for selecting whether the rotation of the PTO shaft 15 is manually turned on or off, or automatically turned on and off in conjunction with the lifting and lowering state of the work machine. .

Next, the work switching dial 9 will be described in detail.
The work switching dial 9 is provided with a first setting position P1 which always fixes the driving mode of the front and rear wheels to “two-wheel drive (2WD)” at one end position, and the driving mode of the front and rear wheels 1F and 1R is sequentially adjacent thereto. Second setting position P2 for fixing the vehicle to “4WD (4WD)”, a third setting position P3 for turning on the front wheel acceleration control and auto brake control which will be described later, assuming the general “work” of the tractor, and the front wheel which will be described later Various controls suitable for "(rotary) tillage" work, which is assumed to be used by most users, including acceleration control (front wheel acceleration control, auto lift control, auto brake control, backup control, accelerator control) Etc.) is forcibly turned on, and the fourth position P4 is arranged.

  The work switching dial 9 is provided with a notch mechanism along the circumference of the rotation base so that it can be positioned at each operation position, and is provided with a dial-side stopper S9 at the rotation base, and a first setting position P1. In order to make the operation range up to the fourth setting position P4, the rotation of the dial 9 is restricted by contacting the vehicle side stoppers S1, S2 at both ends of the operation range.

  In other words, the operation switching dial 9 assumes that “rotary tillage” work and “run on the road” are used by most users when using the tractor, and the on / off setting state of various control devices suitable for both states. Is arranged at both end positions of the dial operation range, for example, compared with a configuration in which a position suitable for the rotary work is arranged in the middle part of the dial operation range, the operator does not need detailed setting position operation. Setting operation can be reduced.

  The third setting position P3 has a brake pressure setting range pb for auto brake control from the middle part (the part rotated to the left in the figure), and this brake pressure is applied to the second setting position P2 side. 0, and the fourth setting position P4 side is set to the maximum pressure (the degree to which the rear wheel 2R is locked). The brake pressure is also set to the maximum pressure at the fourth setting position P4.

  Further, as shown in FIG. 3, a clutch pedal, a left / right brake pedal, and an accelerator pedal 23 are provided below the steering handle 16, and the engine speed is returned to the deceleration side at the rotation base of the accelerator pedal 23. An urging mechanism is provided, and the rotational speed of the engine E is adjusted by the stepping operation or the forward / backward pivoting operation of the accelerator lever 19, and the rotational speed is detected by the engine rotational sensor 24 provided on the engine output shaft. ing.

  In a work vehicle such as the tractor 10, the accelerator setting position held by the accelerator lever 18 is set as a lower limit, the engine speed is increased only when the accelerator pedal 23 is depressed, and the original position is restored when the depression is released. In general, the accelerator lever 19 is set to a high rotation position (full throttle position) and travels at a constant speed. When traveling on the road or in a field, the accelerator lever 19 is set to a low rotation position. Then, the accelerator pedal 23 is depressed to adjust the engine speed and the vehicle speed.

  As shown in FIG. 5, an operation panel 29 made of resin having a recess formed inside is provided on the side of the cockpit 20, and the speed change lever 4 is projected from a lever guide 4g on the panel so as to change the speed change. The sub-transmission device to be described later is switched to three stages (H speed, L speed, and M speed) by rotating the lever 4. Sub-shift position sensors 5L, 5M, 5H, and 5HH that detect the lever operation position are provided at the base of the shift lever 4, and the lever gripper is an upper and lower portion that switches the main transmission 42 from 1st to 8th. A pair of shift switches (shift-up switch 8u, shift-down switch 8d) are provided, and the shift position of the main transmission 42 is switched one by one through an energization command from the controller C2 by an operator's manual operation.

  Further, the shift lever 4 is configured to swing sideways in the left-right direction at the forward rotation position, and keeps the sub-transmission device at the H speed, and includes the “work H” and “road H”. Any one of these is selected, and the number of shiftable stages of the main transmission is changed. Specifically, it is possible to switch from 1 to 8 speeds of the main shift at 1st to 8th speeds for "working H", and the main transmission can be switched to 5th to 8th speeds for "road H". It has a simple structure.

  Similarly, a position lever 21 for changing the height of the work implement R at the rear of the vehicle body is provided on the side of the cockpit 20, and a potentiometer 21 s for detecting the operation position is provided at the base of the position lever 21. The working machine is operated up and down by matching the operating angle of a lift arm 27 described later with respect to the corner. In addition, behind the lever guides of the levers 4 and 21, an operation of a control (hereinafter referred to as backup control) for raising the work implement R by detecting the reverse operation of the vehicle, which is the work implement elevation control device of the present invention, is entered. Backup control ON / OFF switch 1 to be turned off, work implement designation switch 30 for designating the type of work implement R (rotary, draft, external work implement) connected to the vehicle, and the maximum ascending rotational position of the lift arm 27 Raised position adjustment dial 31 set to 1), horizontal changeover switch 32 for switching the horizontal control (rolling control) mode of the work machine R, and accelerator control for detecting the raising operation of the work machine R and lowering the rotation of the engine 12 by a certain amount. It has a configuration provided with various setting tools such as an accelerator control on / off switch 33 for turning on / off the operation of.

  In addition, a cylinder case 26 is provided in the upper portion of the transmission case 13 so as to house a working machine lifting / lowering hydraulic cylinder 25 serving as a working machine lifting / lowering device. Various work machines, in the example of FIG. 3, the rotary work machine R is raised and lowered via a three-point link mechanism 28 including a top link 28a and left and right lower links 28b and 28c. The lift arm base is provided with a lift arm angle sensor 27s for detecting the raised position of the work implement. The left and right lower link 28b is composed of a horizontal control hydraulic cylinder 28c. The piston 28 of the cylinder 28b is expanded and contracted to control the left and right rolling posture of the work machine R and the work machine R. Is detected by a stroke sensor 28s provided in the cylinder 28b.

  Further, as shown in FIG. 6, the working machine lifting / lowering hydraulic cylinder 25 and the horizontal control hydraulic cylinder 28 c divide the pressure oil fed from the hydraulic pump P driven by the engine E by the flow dividing valve 38. Is connected to the working machine lifting / lowering hydraulic cylinder 25, and the other is connected to the horizontal control hydraulic cylinder 28c.

Next, horizontal control of the work machine R connected to the tractor 10 will be described.
The tractor 10 has four horizontal control modes (automatic horizontal, tilt, manual, parallel) and is configured to be switched by the horizontal selector switch 32.

  The “automatic horizontal” mode is a mode mainly operated in a flat field such as a paddy field. The horizontal control hydraulic cylinder 28c is driven with respect to the horizontal reference detected by the inclination sensor 34 provided on the vehicle body, and the working machine is operated. In this mode, R is held in a horizontal state. Further, the right and left rolling posture of the work machine R with respect to the horizontal reference can be arbitrarily set by the tilt adjustment dial 36 provided separately.

  The “tilt” mode is a mode mainly used when working along a contour line on a tilted field. The undulation change of the ground surface is detected by moving and averaging the detection values of the tilt sensor 30. On the other hand, in this mode, the horizontal control hydraulic cylinder 28c is driven to keep the inclination of the work implement R constant. Further, the inclination of the work machine R can be arbitrarily set by the inclination adjustment dial 36.

  The “manual” mode is a mode that is activated when the heights of the hooks of the three-point link mechanism are adjusted when, for example, the work machine R is connected to the tractor 10, and the horizontal manual switch 37 provided separately is pressed. In this manner, the horizontal control hydraulic cylinder 28c is driven to operate the work machine R at an arbitrary inclination with respect to the tractor 10.

  The “parallel” mode is a mode that is used when, for example, a groove forming operation is performed while dropping one wheel of a tractor into a gutter groove, and the horizontal control hydraulic cylinder 28c is set to a certain length. This is a mode in which the work implement R is set in parallel with the tractor 10. In addition, the inclination of the working machine R can be arbitrarily operated by pressing the horizontal manual switch 37 for the fixed length.

Next, the power transmission path of the tractor 10 will be described with reference to FIG. In addition, the arrow of the main auxiliary transmission part shown in a figure shows the transmission direction of the motive power by a constantly meshing gear.
The rotational power of the engine E is intermittently operated by the main clutch 40, and the forward / reverse switching device 41 and the main transmission 42 (first main transmission) in which the rotational power transmitted by the clutch 40 is provided in the transmission case 13. 42a, the second main transmission 42b), and the auxiliary transmission 43 are sequentially transmitted to the rear wheel via the rear wheel differential mechanism 52r, and also via the front and rear wheel drive switching device 3 and the front wheel differential mechanism 52f of the present invention. To transmit to the front wheel 2F.

  Further, the engine E is provided with an accelerator position sensor 44 in the governor mechanism G, an engine rotation sensor 24 is provided on the output shaft, the engine load state of the vehicle is detected by both sensors 44 and 24, and the load increases. In this case, the main shift position is lowered by one step (auto drive load control).

  The forward / reverse switching device 41 is a hydraulic clutch type switching device having two clutches (forward clutch Cf and reverse clutch Cr), whichever is selected according to the operating position of the forward / reverse switching lever (not shown). One clutch Cf (Cr) is pressure-bonded, and the rotational power is transmitted to the first main transmission 42a by forward rotation or reverse rotation.

  Each of the clutches Cf and Cr of the forward / reverse switching device 41 also serves as a booster clutch for switching the shift position of the main transmission 42 on the lower power side. That is, when the main transmission 42 is switched, the clutches Cf and Cr are both disconnected prior to the switching operation, and the forward clutch Cf or the reverse clutch Cr is turned on after the switching is completed.

  The first main transmission 42a is a synchromesh gear transmission including a “1-2 speed” shifting hydraulic cylinder 45A and a “3-4 speed” shifting hydraulic cylinder 45B, which are piston-type shifting actuators. Of the two hydraulic cylinders 45A, 45B, one of the gears of the four gear sets can be obtained by extending or shortening the piston of one cylinder 45A (45B) and moving the shifter engaged with the tip part back and forth. The rotational power is transmitted to the second main transmission 42b through the set. Specifically, the piston of the “1-2 speed” shifting hydraulic cylinder 45A extends to the left side in the figure to become “1st speed”, and the piston shortens to the right side in the figure to become “2nd speed”. The piston of the 3-4 speed hydraulic cylinder 45B for shifting is extended to the left side in the figure to become “3rd speed”, and the piston is shortened to the right side in the figure to become “4th speed”.

  The second main transmission 42b is a hydraulic clutch transmission having a high and low two-stage clutch (high speed clutch Ch, low speed clutch Cl), and either one of the high and low clutch plates is provided by a piston 46 inside the clutch. The rotational power is switched to high and low two stages by pressure bonding, and the power is transmitted to the auxiliary transmission 3b.

  Thus, the main transmission 42 has a shift position of 4 × 2 = all 8 speeds by combining the shift positions of the first main transmission 42a and the second main transmission 42b. When shifting the main transmission 42, the shift control valve is turned on via an energization command of a travel system controller C2, which will be described later, by pressing a shift up switch 8u and a shift down switch 8d provided in the shift lever 4. By switching, the shift actuator, that is, the hydraulic cylinders 45A and 45B or the piston 46 in the clutch is driven to increase or decrease the shift position of the transmission 42 one by one in order.

  In this tractor 10, when the shift lever 4 is set to the “road H” position, the depressing operation of the accelerator pedal 23 increases the shift position by one speed according to the change in the engine speed. It is configured to decelerate or decelerate.

Further, the lubrication configuration of the forward / reverse switching device 41 and the main transmission 42 (the first main transmission 42a and the second main transmission 42b) is configured as shown in FIG.
That is, in the transmission case 13, the clutch shaft 81 of the forward / reverse switching device 41 and the main transmission shaft 82 of the main transmission 42 are rotatably mounted on the same axis, and both the shafts 81 and 82 are spline-fitted. It is configured to rotate integrally, and an O-ring 83 is attached to the joint between both shafts 81 and 82 to seal the spline fitting portion. Oil passages 84 and 85 are provided in the center of the clutch shaft 81 and the main transmission shaft 82, the two oil passages 84 and 85 are connected via a spline fitting space 86, and the front end of the oil passage 84 on the clutch shaft 81 side. Are connected to the A port 87 communicating with the hydraulic pump and the B port 88 opened in the case, and the forward oil passage 84a and the reverse oil passage 84b are branched from the oil passage 84 to advance the forward clutch Cf and the reverse gear. The first clutch gear 89 is configured such that the shaft fitting portion of the clutch Cr is lubricated, and the first oil passages 85a and 85a and the second oil passages 85b and 85b are branched from the oil passage 85 on the main transmission shaft 82 side. The second transmission gear 90 is lubricated.

  Thus, the lubricating oil flows from the oil passage 84 through the forward oil passage 84a and the reverse oil passage 84b to the shaft fitting portions of the forward clutch Cf and the reverse clutch Cr, and then between the clutch shaft 81 and the main transmission shaft 82. It flows to the oil passage 85 through the spline fitting space 86, and further flows to the first transmission gear 89 and the second transmission gear 90 through the first oil passages 85a and 85a and the second oil passages 85b and 85b. Therefore, the spline fitting portion between the clutch shaft 81 and the main transmission shaft 82 can be forcibly lubricated, and durability can be improved.

  The auxiliary transmission 43 is a constant mesh gear type transmission that is switched by a manual operation of the transmission lever 4 via a mechanical interlocking mechanism such as a wire or a link mechanism, and is transmitted from the second main transmission 42b. The rotational power thus transmitted is transmitted through one of three gear sets of “H speed”, “M speed”, and “L speed”, and is output from the auxiliary transmission output shaft 47.

In the tractor 10 configured as described above, as shown in FIG. 17, a 24-speed front-rear shift can be achieved by a combination of an 8-speed main shift and a 3-speed sub-shift.
The rotational power transmitted to the output shaft 47 is transmitted to the left and right rear wheels 2R via the rear wheel differential mechanism 52r, and to the left and right front wheels 2F via the front wheel power branch gear 49 and the front and rear wheel drive switching device 3. It is configured to communicate.

  The front wheel drive switching device 3 is a hydraulic clutch type transmission having two clutches (front wheel constant speed clutch Cw1, front wheel speed increasing clutch Cw2). It is configured so that it can be operated to the “2WD” state, and one of the clutch plates is crimped by a piston inside the clutch. Specifically, when the front wheel constant velocity clutch Cw1 is crimped, the circumference of the front wheel 1F is When the vehicle is driven to “four wheel drive (4WD)” by driving the speed at substantially the same speed as the peripheral speed of the rear wheel 1R, and the front wheel acceleration clutch Cw2 is crimped, the peripheral speed of the front wheel 1F is set to the rear wheel 1R. It is configured to drive approximately twice as much as the peripheral speed and to be in the “front wheel speed increase 4WD” state.

  The front wheel acceleration clutch Cw2 is a clutch that operates during so-called front wheel acceleration control. When the front wheel turning angle sensor 6 detects a steering angle that is greater than a predetermined angle that is assumed to be a turning operation, the traveling system controller C2 Outputs an energization command to switch the control valve to drive the front wheel 2F at high speed.

  Further, the front wheel drive shaft 50 to which power is transmitted from the output shaft 47 is provided with a rear wheel rotation sensor 51r, and the drive shaft on the lower power side of the front and rear wheel drive switching device 3 is provided with a front wheel rotation sensor 51f. In the controller C2, the clutches Cw1 and Cw2 are neutralized every predetermined time, and the detected rotational speeds of the sensors 51r and 51f are compared. When this difference is large, that is, when the slip of the vehicle is large, "four wheel drive" When the difference is small, that is, when the slip is small, “2WD” is set (automatic 2-4WD switching control).

  Further, the left and right drive shafts 55, 55 output from the rear wheel differential mechanism 52r are each provided with a disc brake device 56, and when the turning operation of the vehicle is detected by the front wheel turning angle sensor 6, The brake hydraulic cylinders 53, 53 provided on the side of the transmission case 13 are driven by the energization output of the controller C2, and the brake disc on the inner side of the turning is pressure-bonded to brake the rear wheel 1R on the inner side of the turning (hereinafter referred to as the following) Auto brake control).

  Further, from the lower power side of the main clutch 40, the power is branched to the PTO system through a part of the gear of the forward / reverse switching device 41, and the power includes the PTO clutch 57 and the PTO transmission. 58 and the PTO drive shaft 59 are sequentially transmitted to drive the PTO shaft 15.

Next, a plurality of controllers C1, C2, and C3 serving as the control means C of the present invention will be described with reference to FIGS. 8 to 11 and FIG.
The control means C is a host machine controller C1 that mainly controls the raising and lowering and horizontal posture of the work machine R, and a travel that mainly performs control related to the travel system such as the front and rear wheel drive mode and rear wheel brake of the vehicle. A system controller C2, an operation panel controller C3 for mainly processing signals from various switch setting devices on the operation panel 29 on the side of the cockpit 20, and a pilot lamp and a liquid crystal monitor M on the meter panel 7. It is composed of a meter panel controller C4 for controlling display.

  Each of the controllers C1 to C4 is provided with a CPU for processing various signals and storage means (RAM, EEPROM) for storing various control programs and sensor signals, and the work machine system controller C1 and the traveling system controller C2. Are connected by the CAN method, and the work machine system controller C1, the operation panel controller C3, and the meter panel controller C4 are connected by synchronous communication in which signals are sent at predetermined time intervals.

  Further, the work machine system controller C1 is configured so that a controller C5 of a portable checker can be connected, and the sensors and actuators connected to the controllers C1 and C2I are inspected and adjusted.

  Control valves for driving various sensors and actuators connected to the controllers C1 and C2I are as follows. The work machine system controller C1 receives the work switching dial 9 of the present invention, the potentiometer 21s at the base of the position lever 21, the lift lever 14, the front wheel turning angle sensor 6, the lift arm angle sensor 27s, and the left / right inclination angle of the vehicle body at the input section. An inclination sensor 34 for detecting, a stroke sensor 28s for detecting the right and left inclination of the work machine R provided in the three-point link mechanism, a depth sensor 62 connected when the rotary work machine R is attached and performing plowing depth control, and a draft work machine A draft sensor 63 for detecting the traction force when attached is connected.

  Further, at the output portion of the work machine controller C1, the lift arm 27 is turned up and down, that is, the solenoids 64a and 64b of the proportional flow rate control valve for extending and retracting the work machine lifting and lowering hydraulic cylinder 25, and the left and right rolling of the work machine R. Solenoids 65a and 65b of switching control valves for extending and contracting the horizontal control hydraulic cylinder 28c for adjusting the posture are connected and provided.

  Further, the traveling system controller C2 detects the set positions of the shift up / down switches 8u, 8d, the shift lever position sensors 5L, 5M, 5H, 5HH and the first main transmission 42a at the input section. Shift sensors 67a, 67b, 67, second main shift sensors 68H, 68L for detecting the switching state of the second main shift position 42b, forward / reverse switch lever (not shown) forward switch 18f at the base, reverse switch 18r, forward / rear Wheel rotation sensors 51f and 51r, a PTO on / off switch 22a, an independent PTO control on / off switch 22b, and the like are connected, and solenoids 69a, 69b, and 69c of switching control valves that switch the first main transmission 42a to the output section. , Solenoids 70h and 70l of switching control valves for switching the second main transmission 42b, switching control valves for switching between forward and backward travel Solenoid 71f, are provided in connection 71r, and the solenoid 72a of the switching control valve for crimping wheel constant velocity clutch Cw1 before and after the solenoid 72b of the switching control valve for crimping the front wheel acceleration clutch Cw2.

  As shown in FIG. 11, the operation panel controller C3 turns on / off the backup control on / off switch 1, the work implement designation switch 30, the horizontal selector switch 32, and the accelerator control for turning on / off the backup control in this input section. An accelerator control on / off switch 33, an inclination adjusting dial 36, a horizontal manual switch 37, a raising position adjusting dial 31, a tilling depth adjusting dial 35, and the like are connected.

  Further, as shown in FIG. 4, the meter panel controller C4 has a "backup" control pilot lamp L1 on the left side of the panel, and an "upstop" control pilot lamp that stops the rotation of the PTO shaft 15 when the work implement is raised. A pilot lamp indicating a plurality of control operations, such as L2, the "accelerator" control pilot lamp L3, the "auto brake" control pilot lamp L4, and the "auto lift" control pilot lamp L5, is connected and provided. A pilot lamp L6 indicating whether the shaft 15 is rotating or stopped, a lamp L7 indicating that the work machine is in the raised position, and a liquid crystal display M on the right side of the engine tachometer 75 and front and rear wheels are provided. The drive mode is “2WD (2WD)” or “4WD (4WD)” or the front wheel It is provided to connect the pilot light L8~L10 indicating which a front wheel acceleration control for accelerating ".

In the tractor 10 configured as described above, various controls are set as in the flowcharts shown in FIGS.
First, when the power supply system is turned on by the engine key switch of the tractor 10 and the engine E is started, the work machine system controller C1 reads the connection state and setting state of the sensors and switches as shown in FIG. Further, various control programs and setting states stored in the EEPROM are read. A part of the information is read into the RAM (STEPs 1 to 3).

  Next, it is determined by the shift lever position sensor 5HH whether or not the shift lever 4 has been operated to the on-road H position. If this is YES, the process proceeds to STEP 5 and a control setting process subroutine suitable for on-road travel is performed. To process.

  As shown in FIG. 13, the control setting process suitable for the road running includes first the backup control and the accelerator control according to the position of the work implement switching dial 9 and the on / off setting states of the on / off switches 1 and 33. The power transmission state of both the clutches Cw1 and Cw2 of the front and rear wheel drive switching device 3 is also set to “OFF” and the vehicle is set to “2WD” (STEP5-2).

Further, when the backup control on / off switch 1 or the accelerator control on / off switch 33 is turned ON again, this change is validated and the control is executed (STEP 5-5).
Thereby, when the position of the shift lever is set to the road running position, various controls are temporarily turned off in preference to the setting state of the work switching dial 9 and the setting state of the on / off switch of each control. Even if the work switching dial 9 is set to the "work" position or "tillage" position, the front wheel acceleration control, autolift control, autobrake control, and even the accelerator control are activated even when traveling at high speed on general roads. Therefore, it is possible to travel on the road while ensuring the safety of the vehicle. In addition, since the backup control and the accelerator control including the respective on / off switches can be turned on / off again under the confirmation of the operator, the operability of the vehicle is not impaired.

  In FIG. 12, when the speed change lever 4 is other than “road running H”, the setting position of the work switching dial is determined. If it is the “2WD” position, the process proceeds to FIG. 13. If it is the “cultivation” position, the process proceeds to STEP 8, and if it is any other position, the process proceeds to STEP 7, and each subroutine is processed.

  As shown in FIG. 14, the setting process suitable for the “cultivation” work in STEP 8 includes turning control such as front wheel acceleration control, auto lift control, and auto brake control (STEP 8-1). Backup control and accelerator control are turned on and set (STEP8-2, 8-3), and each control is executed.

If it is determined in STEP 6 in FIG. 12 that the work switching dial 9 is set to another position, a setting process suitable for the general work of the tractor is performed as shown in FIG.
Here, it is determined whether or not it is immediately after the engine is started for the first time. If this is YES, the backup control or accelerator control on / off state is set according to the setting of the stored value transferred from the EEPROM to the RAM. Is set to the mode setting state of the work implement lifting system and horizontal control system described later. Further, when it is not immediately after the engine is started, the setting position of the work switching dial 9 is further determined to determine whether or not it is immediately after the change from the “till” position. Thus, each control is set to a setting state suitable for tillage work. If it is immediately after the change from the “4WD” position, the on / off setting state at the time of running on the road stored in the RAM is taken over and set. Thereafter, if there is a change in the setting state of the backup control ON / OFF switch 1 and the accelerator control ON / OFF switch 33, the changed setting state is stored in the RAM and various controls are executed.

Next, the relationship between the work switching dial 9 and the work implement lifting / lowering control system and work implement horizontal control system will be described with reference to FIG.
As described above, the mode of the work implement lifting control system has a plowing depth control mode performed in the rotary plowing operation, a draft control mode performed in the drafting operation, and an external hydraulic pressure take-out mode in the case of operating another external work implement. It has a configuration.

  These work implement lifting / lowering control modes are configured to be switched by the work implement designation switch 30, and each mode can be arbitrarily set at the “2WD”, “4WD”, and “work” positions of the work changeover dial 9. In addition, the tilling depth control mode is forcibly set at the “plow” position. Further, in the setting operation of the work switching dial 9, even when switching from the “till” position to the “work” position, the plowing depth control mode set at the “plow” position is taken over. When switched by the work implement designation switch 30, the mode after the switching can be set.

  Similarly, the work implement horizontal control mode is configured to be switched to the four modes by the horizontal changeover switch 32 as described above. However, at the “cultivation” position, the work implement horizontal control mode is forcibly shifted to the automatic horizontal mode. Further, the setting of the work switching dial 9 is configured to take over the automatic horizontal mode set at the “till” position even when the “plow” position is switched to the “work” position, and thereafter When switched by the horizontal selector switch 32, the mode after switching can be set.

  As a result, the work implement lifting control system and the work implement horizontal control system of the tractor 10 as well as the turning control system set the work switching dial 9 to the “till” position, so that the setting state corresponding to the rotary work can be obtained. Since it is set, it is possible to eliminate setting mistakes and reduce the operator's setting operation.

  As another form of the present invention, the work switching dial 9 may be configured as a lever so that each set position can be reciprocated, or the set position can be electrically switched as a rubber tact switch. Further, at the “2WD” position, which is the first setting position, a slip state is detected by the detection of the front and rear wheel rotation sensors 51f and 51r, and the traveling form of the vehicle is automatically set to 2WD and 4WD according to the slip state. It is good also as a setting position which operates 2-4WD automatic switching control switched by.

  In the tractor, the work implement ascent control device is applied to backup control. However, this may be applied to auto lift control that operates in conjunction with the turning operation of the vehicle. Moreover, in the said structure, although it assumed the agricultural tractor, it was set as the structure provided with "front-wheel speed-up control" which drives the peripheral speed of the front wheel 2F at a speed higher than the peripheral speed of the rear wheel 2R when the vehicle turns. In other types of vehicles, a configuration in which the rear wheel peripheral speed is driven at a lower speed than the front wheel peripheral speed, that is, a front and rear wheel drive switching device that gives a rotational difference to the front and rear wheel peripheral speeds may be used.

  As another form of the present invention, when the work switching dial 9 is operated to the fourth position P4, front wheel acceleration control, auto lift control, auto brake control, backup control, accelerator control, and automatic horizontal control are once forced. In addition, a setting tool that can turn on / off these auto lift control, auto brake control, backup control, accelerator control, and automatic horizontal control can be provided. Good. By comprising in this way, it can be set as the driving | running state according to an operator's liking.

  Further, when the work switching dial 9 is operated to the fourth position P4, front wheel acceleration control, auto lift control, auto brake control, backup control, accelerator control, and horizontal control are forcibly turned on, The automatic leveling control has an automatic horizontal mode for holding the work implement R horizontally and an inclination mode for making the work implement parallel to the ground in a mode mainly used when working along a contour line on a tilted field. When the change dial 9 is changed from the third position P3 to the fourth position P4, the automatic horizontal mode of the horizontal control is set first, and it can be selected and changed to the tilt mode by operating the on / off switch. Good. With this configuration, it is possible to obtain an operation state that suits the operator's preference while giving priority to the normal operation state.

  Furthermore, as another form of the present invention, the main shift position may be switched to a shift position suitable for running or work by an actuator according to the set position of the work switching dial 9.

  That is, when the fourth position P4 in the standard tillage work state is operated, various controls relating to the work implement are automatically set, and the shift position is automatically set to a position suitable for the tillage work. . For example, as shown in FIG. 17, if the minimum shift position of the shift position assuming the rotary tillage work, that is, the sub shift position is L at the shift position of the tractor 10, the main shift position is set to the eighth speed, If the sub-shift position is M, the main shift position is switched to the first speed. Further, when the work switching dial 9 is operated to the first position P1 assuming traveling on the road, the main shift is switched to the fifth speed.

  Thus, the control setting operation and the shift operation are reduced, and the operability can be improved.

The figure which shows the work switching dial under a meter panel. The table which shows the dial setting position and the ON / OFF state of each control. The whole tractor side view. The front view of a meter panel. The perspective view of the operation panel part by the side of a cockpit. 1 is a partial hydraulic circuit diagram of a tractor. The transmission mechanism figure of a tractor. The figure which shows the contact state of each controller. The figure which shows the connection state of a work machine system controller. The figure which shows the connection state of a traveling system controller. The figure which shows the connection state of the controller for operation panels. The flowchart which shows the outline | summary of control. The flowchart which shows the outline | summary of the control setting process suitable for driving | running | working on a road. The flowchart which shows the outline | summary of the control setting process suitable for tillage work. The flowchart which shows the outline | summary of the control setting process suitable for general work. The cutaway side view of the principal part. The table | surface which shows the relationship between a work | work and traveling speed (shifting position).

Explanation of symbols

C1 Work machine system controller C2 Travel system controller 1 Setting tool (backup control on / off switch)
2F Front wheel 2R Rear wheel 3 Front wheel drive switching device 4 Shift lever 9 Setting device (work switching dial)
10 Tractor 30 Work implement designation switch

Claims (1)

  A work implement elevating device (25) for elevating the rotary work implement (R) to a working position and a non-working position, a work implement elevating control means (C1) for controlling the work implement elevating device (25), and a front wheel (2F) The front wheel drive switching device (3) for switching the driving mode of the vehicle to the “two-wheel drive” state or the “four-wheel drive” state by switching the driving mode to the non-driving state or the driving state, and switching of the front wheel driving switching device (3) A traveling control means (C2) for controlling the state is provided, a setting device (9) for switching the set position between the traveling position (P1) and the tilling position (P4) is provided, and in the traveling position (P1), the traveling mode of the vehicle body Is set to the “two-wheel drive” state, and the work implement lifting control is set to OFF. At the tillage position (P4), the traveling mode of the vehicle body is set to the “four wheel drive” state, and the work implement lifting control is set to ON. Agriculture In the tractor for a vehicle, there is provided a setting tool capable of independently selecting front wheel acceleration control, auto lift control or auto brake control, and when the setting device (9) is operated to the tillage position (P4), the setting tool An agricultural tractor configured to forcibly turn on front wheel acceleration control, autolift control, or autobrake control selected and set by.

Images