JP5802036B2 - Work vehicle - Google Patents

Description

  The present invention relates to a work vehicle that performs left-right tilt control of a traveling machine body.

  Inclination driving means for causing the traveling body supported by the pair of left and right traveling devices to be tilted left and right with respect to the left and right traveling devices, and inclination detecting means for detecting the left and right inclination of the traveling body, 2. Description of the Related Art Conventionally, a work vehicle provided with a control unit that executes a tilt control for holding a traveling machine body at a predetermined left and right tilt angle with respect to a horizontal direction by the tilt driving means based on a detection result is well known. According to the present invention, even when traveling in a undulating place, the traveling machine body can be held at a predetermined left-right inclination angle with respect to the horizontal direction.

  As a further improvement, a control unit is configured to stop the execution of the tilt control when the traveling aircraft turns left and right during the tilt control. A work vehicle shown in Patent Document 1 that efficiently prevents the traveling machine body from becoming unstable due to tilt control during a right or left turn has been developed and is publicly known.

Japanese Patent Publication No. 7-32645

In the work vehicle described in the above document, it is recognized that the traveling vehicle is turning left and right even when the steering lever is slightly swung left and right for the purpose of fine adjustment of the traveling direction of the traveling vehicle during high speed traveling. In recent years, the tilt control is stopped, but in recent years, the travel speed has increased, and if the tilt control is stopped every time fine adjustment of the travel direction of the vehicle is performed, the undulating travel surface can be moved at high speed. When traveling, the traveling aircraft may not be inclined to the left and right with high sensitivity with respect to the left and right traveling aircraft, and the operator may feel a response delay with respect to holding the left and right inclination of the traveling aircraft. .
According to the present invention, in a work vehicle that executes tilt control for holding a traveling machine body at a predetermined left and right tilt angle with respect to the horizontal direction based on a detection result of the tilt detection means, the tilt control is performed during left and right turn travel. It is an object of the present invention to provide a work vehicle in which an operator does not feel a delay in response to tilt control or is difficult to feel even when the traveling speed is high.

In order to solve the above-mentioned problem, firstly, tilt drive means 31, 31 for causing the traveling machine body 2 supported by the pair of left and right traveling devices 1, 1 to be tilted left and right with respect to the left and right traveling devices 1, 1; And an inclination detecting means 74 for detecting the right and left inclination of the traveling machine body 2. Based on the detection result of the inclination detecting means 74, the traveling machine body 2 is predetermined in the horizontal direction by the inclination driving means 31, 31. A work vehicle provided with a control unit 73 that executes tilt control to be held at a predetermined left-right tilt angle, a steering lever 66 that performs a steering operation by swinging left and right from a neutral position N, and the steering lever 66 The operation position detecting means 77 for detecting the left and right swing position from the neutral position N is provided. The operation position detecting means 77 is provided at the neutral position N of the steering lever 66 and the neutral position N in each of the left and right swing ranges. In the near side range And non-regulatory domain, left and right of the regulating range is in the range of the far side from the neutral position N in the swing range and detectable configuration respectively, the control unit 73, the steering lever 66 by the operating position detecting means 77 When it is detected that the steering lever 66 has been swung to either the left or right regulation range, the tilt control is stopped while the steering lever 66 is moved to the left or right non-regulation range by the operation position detecting means 77. When it is detected that the head is swung to the neutral position N or to the neutral position N , the tilt control is continuously executed.

  Secondly, the control unit 73 swings the steering lever 66 when the operation position detecting means 77 detects that the steering lever 66 is swung to either the left or right regulation range. When the operation position detecting means 77 detects that the steering lever 66 has been swung to either the left or right non-restricted range while performing the turning control for steering the traveling machine body 2 to the side. Further, the present invention is characterized in that direction correction control for steering the traveling machine body 2 by a predetermined angle smaller than that during turning control is performed on the swing side of the steering lever 66.

  Third, the steering lever 66 is configured such that the left and right swinging operation can be performed with an operation force lighter than that in the non-regulated range.

  Fourth, when the operation position detection unit 77 detects that the steering lever 66 has been swung to any one of the left and right unrestricted ranges, the control unit 73 has a swing-side travel device. 1 is controlled to decelerate and turn to a slower driving speed than the non-oscillating side travel device 1, while the operating position detecting means 77 swings the steering lever 66 to either the left or right regulation range. In the case where it is detected, the brake turning control for braking the swinging travel device 1 is performed.

  According to the above configuration, the side close to the neutral position in each of the left and right swing ranges of the steering lever is set as the non-restricting range, the side far from the neutral position is set as the limiting range, and the steering lever is in the non-restricting range of either the left or right side. When the swinging operation is performed, the tilt control is continued. On the other hand, when the steering lever is swung within one of the left and right regulation ranges, the tilt control is stopped. For this reason, in a work vehicle whose traveling speed has been increased in recent years, the inclination control is executed every time the steering lever is swung a small amount in the left-right direction for the purpose of fine adjustment of the traveling direction of the traveling body during high-speed traveling. When it is stopped and the operator feels a delay in the response of the left and right tilting of the traveling aircraft, it can be prevented in advance, and the steering lever is swung to the left and right for the purpose of turning the traveling aircraft to the left and right. As a result, the execution of the tilt control is stopped, and the traveling vehicle body can be stably turned left and right.

  Specifically, when it is detected by the operation position detection means that the steering lever has been swung to either the left or right regulation range, while turning control is performed to steer the traveling machine body, When it is detected by the operation position detection means that the steering lever has been swung to either the left or right non-restricted range, a predetermined angle smaller than that at the time of turning control on the swinging side of the steering lever, If direction correction control to steer the traveling aircraft is performed, the execution of the tilt control is stopped only when the traveling aircraft is largely turned left and right, so that the operator feels a response delay due to the stop of the execution of the tilt control, It can be prevented more efficiently.

  In addition, if the steering lever is configured so that the left and right swinging operation can be performed with an operation force lighter than the regulation range in the non-regulated range, the steering lever from the neutral position to a range where a strong operating force is required. Since the execution of the tilt control is stopped for the first time when the is swung left and right, it is possible to smoothly stop the execution of the tilt control as needed without giving the operator a sense of incongruity.

  Further, when it is detected by the operation position detecting means that the steering lever has been swung to any one of the left and right unrestricted ranges, the swing side travel device is moved from the non-swing side travel device. On the other hand, if the operation position detecting means detects that the steering lever has been swung to either the left or right regulation range, the decelerating turning control for decelerating to a slower driving speed is performed. If brake turning control that brakes the traveling device is performed, the execution of the tilt control is stopped only when the traveling body is largely turned left and right, so that it is more efficient that the operator feels a response delay due to the stop of the execution of the tilt control. Can be prevented.

It is a whole side view of the self-removing combine to which the present invention is applied. (A) is a side view of the crawler type traveling apparatus when the traveling machine body is lowered, and (B) is a side view of the crawler type traveling apparatus when the traveling machine body is raised. It is a conceptual diagram which shows the power transmission structure of the traveling system of this combine. It is a hydraulic circuit diagram which shows the structure of the hydraulic device mounted in this combine. It is a top view of the control part in a cabin. It is explanatory drawing which shows the operation state according to the left-right inclination angle of a multi lever. It is a top view of an operation panel. It is a block diagram of a control part. It is a processing flowchart of the horizontal automatic control which a control part performs. It is a processing flowchart of the subroutine of inclination determination. It is a processing flow figure of a subroutine of valve operation. It is a processing flowchart which shows another embodiment of the horizontal automatic control which a control part performs. It is a processing flowchart which shows another embodiment of the horizontal automatic control which a control part performs.

  FIG. 1 is an overall side view of a self-removing combine to which the present invention is applied. A combine that is a type of work vehicle includes a traveling machine body 2 supported by a pair of left and right crawler type traveling devices (traveling devices) 1, and a preprocessing unit 3 that is connected to the front part of the traveling machine body 2 so as to be movable up and down. It has.

  The pre-processing unit 3 is configured to perform the harvesting operation of the grain culm in the field and to convey the harvested culm backward to the traveling machine body 2 side. The pre-processing unit 3 is arranged in front of the traveling machine body 2. It is driven up and down by expansion and contraction of a lifting cylinder 4 that is a hydraulic cylinder provided between the lower end of the section and the preprocessing section 3.

  The traveling machine body 2 is provided with a threshing device (not shown) on the left half of the machine frame 2a in the front-rear direction supported by the left and right crawler traveling devices 1 and 1, and a control unit 6 ( The cabin 7 is provided so as to cover the cabin 7 (see FIG. 5), and a Glen tank 8 is provided behind the cabin 7.

  The combine is driven forward by the left and right crawler type traveling devices 1 and 1 in a state where the lowered preprocessing unit 3 is cut and transported and the threshing device is threshed and selected in the field. By doing so, the harvesting work of the field is performed.

  Specifically, the culm harvested by the preprocessing unit 3 is transported backward and passed to the threshing device side of the traveling machine body 2. The cereals passed to the threshing device side are threshed to become waste, and are left or cut, and discharged from the rear end of the traveling machine body 2 while being threshed by the threshing device. The processed products are sorted into grains such as straw and wastes such as swarf by sorting winds obliquely upward at the rear and raised in the threshing apparatus. The sorted discharged matter is discharged out of the machine from the rear end of the traveling machine body 2, and the sorted grain is conveyed and stored in the Glen tank 8.

  The grain in the Glen tank 8 is discharged out of the machine by an auger 9 provided on the traveling machine body 2 so as to be able to turn left and right and to be moved up and down. Incidentally, the auger 9 includes a vertical cylinder 11 in the vertical direction installed on the right side of the rear end portion of the traveling machine body 2, and a discharge cylinder 12 that is supported by the upper end of the vertical cylinder 11 and extends linearly. Has been. The discharge cylinder 12 is supported by the vertical cylinder 11 so as to be swingable up and down, and an auger elevating cylinder 13 which is a hydraulic cylinder is provided between an upper end side of the vertical cylinder 11 and a proximal end side of the discharge cylinder 12.

  The auger 9 is turned up and down by turning the vertical cylinder 11 up and down by the expansion and contraction of the auger raising / lowering cylinder 13 while the vertical cylinder 11 is turned around its own axis. In the Glen tank 8, in the vertical cylinder 11, and so on, the grains in the Glen tank 8 can be discharged from the distal end portion (the distal end portion of the auger 9) of the discharge cylinder 12 positioned at a predetermined position by turning left and right and raising and lowering. In the discharge cylinder 12, conveying spirals 8a, 11a, 12a for conveying the grains are installed.

  2A is a side view of the crawler type traveling device when the traveling machine body is lowered, and FIG. 2B is a side view of the crawler type traveling device when the traveling machine body is raised. Each crawler type traveling device 1 includes a traveling frame 1a in the front-rear direction, a plurality of front and rear wheels 14 supported in an idle state at a lower portion of the traveling frame 1a, and an idler on the upper rear end portion of the traveling frame 1a. An idler wheel 16 supported in a state, a drive sprocket 17 which is a drive wheel disposed on the upper side of the front end portion of the traveling frame 1a, an upper wheel 18 disposed on the middle part of the traveling frame 1a, A movable roller 19 disposed below the middle part of the traveling frame 1a and a synthetic resin crawler 21 that is wound around an idler wheel 16 and a drive sprocket 17 to form an annular shape are provided.

  The plurality of rollers 14, the upper roller 18, and the movable roller 19 are in contact with the annular crawler 21 from the inside to prevent the crawler 21 from loosening. The drive sprocket 17 and the upper wheel 18 are rotatably supported on the traveling machine body 2 side. In particular, the drive sprocket 17 is configured to be rotationally driven by transmission of engine power on the traveling machine body 2 side. The crawler type traveling device 1 is driven to travel forward or backward by the rotation of the drive sprocket 17 in the forward or reverse direction.

  In addition, the movable wheel 19 is rotatably attached to the distal end portion of the support arm 22 attached to and supported by the traveling frame 1a so as to protrude and swing up and down in the middle of the traveling frame 1a. The movable wheel 19 is allowed to move up and down, and the vertical movement of the movable wheel 19 makes it easy to stably maintain the tension of the crawler 21.

  Between the left and right crawler type traveling devices 1, 1 having the above configuration and the body frame 2 a of the traveling body 2, an elevating mechanism 23 that lifts and lowers the support side portion of the traveling body 2 is provided. In other words, the traveling machine body 2 is supported by the left and right crawler traveling devices 1 and 1 by a pair of left and right lifting mechanisms 23 so as to be movable up and down.

  For this reason, the traveling machine body 2 is moved to the left and right crawler type traveling devices 1, 1 by displacing the elevation height of the elevation mechanism 23 on the left and right side with respect to the elevation height of the elevation mechanism 23 on the other side. On the other hand, it is possible to incline left and right.

  Specifically, the elevating mechanism 23 includes a pair of front and rear links 24 and 26 for connecting the traveling machine body 2 to the traveling frame 1a so as to be movable up and down, and a link 26 on one front and rear side (rear side in the illustrated example). A main arm 27 that swings back and forth integrally, a driven arm 28 that swings back and forth integrally with the link 24 on the other side of the front and rear, a connecting rod 29 in the front-rear direction that connects the main arm 27 and the driven arm 28, and expansion and contraction And a horizontal cylinder 31 that is a hydraulic cylinder that drives the main arm 27 to swing back and forth by operation.

  The horizontal cylinder 31 is bridged between the body frame 2a and the main arm 27, and the main arm 27 and the driven arm 28 are swung back and forth by the expansion and contraction of the horizontal cylinder 31, and the front and rear links 24, 26 is integrally rocked up and down, and the lifting mechanism 23 side portion of the traveling machine body 2 is driven up and down with respect to the left and right crawler type traveling devices 1 and 1. That is, the horizontal cylinders 31, 31 provided separately for the left and right crawler type traveling devices 1, 1 constitute an inclination driving means for inclining the traveling machine body 2 to the left and right crawler type traveling devices 1, 1. Yes. Incidentally, when the traveling machine body 2 is raised and lowered by the lifting mechanism 23, the drive sprocket 17 and the upper roller 18 installed on the traveling machine body 2 side are lifted and lowered with respect to the crawler traveling device 1 integrally with the traveling machine body 2. .

  FIG. 3 is a conceptual diagram showing the power transmission configuration of the traveling system of this combine. The engine 32 disposed below the rear portion of the cabin 7 drives the left and right crawler type traveling devices 1, 1, the pretreatment unit 3, the threshing device, the auger 9, and the like. In this, engine power is transmitted to the left and right crawler type traveling devices 1, 1 via the HST 33 and the transmission 34.

  Specifically, the engine power that is steplessly shifted by the HST 33 including the HST pump 33a and the HST motor 33b is input to the transmission 34 in the transmission case 36. The crawler type traveling devices 1 and 1 are driven.

  The transmission 34 includes a traveling shaft 37 to which transmission power from the HST 33 is transmitted, a sub-transmission mechanism 38 to which power of the traveling shaft 37 is transmitted, a branch shaft 39 to which power of the sub-transmission mechanism 38 is transmitted, The intermediate shaft 41 and the turning mechanism 42 to which the power of the shaft 39 is gear-transmitted, the switching mechanism 43 to which the power of the turning mechanism 42 and the power of the branch shaft 39 are input, and the branch shaft 39 or the turning mechanism via the switching mechanism 43 42, a switching shaft 44 to which any one of the motive power is transmitted, a pair of left and right cylindrical transmission shafts 46, 46 provided on the left and right sides of the intermediate shaft 41, and a left and right cylindrical transmission shaft 46, 46, a pair of left and right side clutches 47 and 47 for intermittently transmitting the power of the intermediate shaft 41 separately, and a pair of left and right drive clutches 48 for intermittently transmitting the power of the switching shaft 44 to the left and right cylindrical transmission shafts 46 and 46, respectively. , 48 The left and right cylindrical drive shafts 46 and 46 are respectively provided with a pair of left and right drive shafts 49 and 49 to which the power is transmitted, and the left and right drive shafts 49 and 49 are provided with the drive sprockets 17 and 17, respectively. The drive shafts 49 and 49 drive the left and right crawler type traveling devices 1 and 1 to travel forward or backward by the drive shafts 49 and 49.

  The auxiliary transmission mechanism 38 has a large-diameter high-speed gear 38 a that is supported on the traveling shaft 37 so as to freely rotate, a small-diameter low-speed gear 38 b that is supported on the traveling shaft 37 so as to freely rotate, and power of the traveling shaft 37. And a shifter member 38c for switching between transmission to the high speed gear 38a or the low speed gear 38b. The sub-transmission mechanism 38 transmits the power of the traveling shaft 37 to the high speed gear 38a to switch to the high speed state in which the high speed power is transmitted to the branch shaft 39, while the low speed gear 38b has the traveling shaft. By transmitting the power of 37, switching to the low speed state in which the low speed power is transmitted to the branch shaft 39 is performed.

  The turning mechanism 42 includes a turning transmission shaft 51, a hydraulic deceleration turn clutch 42a for intermittently transmitting the power of the branch shaft 39 to the turning transmission shaft 51, and a braking force transmitted to the turning transmission shaft 51 for braking. The brake turn clutch 42b and the deceleration turn clutch 42a are configured such that when one is connected, the other is disconnected.

  The turning mechanism 42 connects the power of the engine (specifically, the branch shaft) to the transmission downstream side of the turning transmission shaft 51 by connecting the deceleration turn clutch 42a (disconnecting the brake turn clutch 42b). 39 is switched to the transmission state in which the transmission power is transmitted to 39, while the deceleration turn clutch 42a is disconnected (the brake turn clutch 42b is connected), so that the downstream side of the transmission shaft 51 for turning is braked. Switched.

  The switching mechanism 43 is supported on the switching shaft 44 so as to be freely rotatable, and the decelerating turning gear 43a to which the power of the turning transmission shaft 51 is always transmitted, and is supported on the switching shaft 44 so as to be freely rotatable and branched. A spin turning gear 43b to which the power of the shaft 39 is always transmitted is provided, and a shifter member 43c that transmits the power of either the speed reducing turning gear 43a or the spin turning gear 43b to the switching shaft 44.

  Then, the switching mechanism 43 switches the shifter member 43c so that the power of the decelerating swivel gear 43a is transmitted to the switching shaft 44, whereby the power or braking force from the swivel mechanism 42 is applied to the left and right drive clutches 48, 48. By switching the shifter member 43c so that the power of the spin turning gear 43b is transmitted to the switching shaft 44 while switching to the decelerated turning state to be transmitted, the left and right drive clutches 48, 48 are connected to the branch shaft 39 from the branch shaft 39. Switching to a spin turning state where power is reversed and transmitted.

  That is, the power transmitted from the branch shaft 39 to the switching shaft 44 via the switching mechanism 43 and the power transmitted from the branch shaft 39 to the switching shaft 44 via the turning mechanism 42 and the switching mechanism 43 are the drive clutch 48. Is intermittently transmitted to the crawler type traveling device 1.

  By the transmission 34 having the above-described configuration, the traveling machine body 2 including the pair of left and right crawler type traveling devices 1 and 1 has one kind of straight traveling mode and three kinds of turning modes.

  First, in the straight-ahead mode (straight-ahead control), the left and right drive clutches 48 are disconnected and the left and right side clutches 47 are connected. Thereby, the traveling machine body 2 travels straight.

  Further, in the deceleration turning mode (deceleration turning control) which is the first turning mode, the left and right side clutches 47, 47 are switched to the disconnected state while the non-turning side is maintained in the connected state, and the left and right drive are driven. While the turning sides of the clutches 48 and 48 are switched to the connected state, the non-turning side is switched to the disconnected state, the turning mechanism 42 is switched to the transmission state, and the switching mechanism 43 is switched to the deceleration turning state. Accordingly, the driving speed of the crawler traveling device 1 on the turning side to which the power from the driving clutch 48 is transmitted is slower than the crawler traveling device 1 on the non-turning side to which the power from the side clutch 47 is transmitted. Driven (decelerated to a slow speed), the traveling machine body 2 is turned to the turning side.

  Also, in the brake turning mode (brake turning control), which is the second turning mode, the left and right side clutches 47, 47 are switched to the disconnected state while the non-turning side is maintained in the connected state, and the left and right drive are driven. While the turning sides of the clutches 48 and 48 are switched to the connected state, the non-turning side is switched to the disconnected state, the turning mechanism 42 is switched to the braking state, and the switching mechanism 43 is switched to the deceleration turning state. As a result, the braking force from the turning mechanism 42 side is transmitted to the crawler type traveling device 1 on the turning side, and the brake is applied to stop or decelerate, so that the crawler type traveling device 1 on the turning side has the side clutch 47. The driving speed becomes slower than the crawler type traveling device on the non-turning side to which the motive power is transmitted or is stopped, and the traveling machine body 2 is turned to the turning side.

  Further, in the spin turning mode (spin turning control), which is the third turning mode, the turning side of the left and right side clutches 47, 47 is switched to the disconnected state, while the non-turning side is maintained in the connected state, and the left and right driving are performed. The turning side of the clutches 48, 48 is switched to the connected state, while the non-turning side is switched to the disconnected state, and the switching mechanism 43 is switched to the spin turning state. As a result, the turning sides of the left and right crawler type traveling devices 1 and 1 are driven in the opposite direction to the non-turning side, and the traveling machine body 2 is spin-spinned on the spot.

  FIG. 4 is a hydraulic circuit diagram showing the configuration of the hydraulic device mounted on the combine. In the present combine, expansion and contraction of the elevating cylinder 4, the auger elevating cylinder 13, and the left and right horizontal cylinders 31, 31 are controlled by the hydraulic device 52 housed on the lower side of the front portion of the cabin 7, and the deceleration turn clutch 42a, The side clutches 47 and 47 and the left and right drive clutches 48 and 48 are controlled to be intermittent.

  Specifically, the hydraulic device 52 includes a hydraulic pump 54 that pumps hydraulic oil from an oil tank 53, a lift valve 56 that is an electromagnetic valve that supplies and discharges hydraulic oil to and from the lift cylinder 4, and a deceleration turn clutch. A deceleration turn valve 57 that is an electromagnetic valve that supplies and discharges hydraulic oil to and from the a and a horizontal valve 58 that is a pair of electromagnetic valves that individually supply and discharge hydraulic oil to and from the left and right horizontal cylinders 31 and 31. 58, a pair of drive valves 59, 59 that are electromagnetic proportional control valves that individually supply and discharge hydraulic oil to and from the pair of drive clutches 48, 48, and supply of hydraulic oil to the auger elevating cylinder 13 An auger lift valve 61 that is a solenoid valve that discharges and a side clutch that is a solenoid valve that operates a single hydraulic side clutch cylinder 62 that intermittently connects the left and right side clutches 47, 47. And a Chibarubu 63.

  The hydraulic pump 54 is driven by engine power, and the hydraulic oil from the oil tank 53 is transferred to the lift valve 56, the deceleration turn valve 57, the horizontal valve 58, the drive valve 59, the auger lift valve 61, the side clutch valve 63, and the like. Pump.

  The elevating valve 56 has an ascending position that forms a flow path for supplying hydraulic oil from the hydraulic pump 54 to the extension chamber 4a of the elevating cylinder 4 so as to elevate the pretreatment unit 3 by elongating operation of the elevating cylinder 4. A lowering position for forming a flow path for discharging the hydraulic oil in the extension chamber 4a of the elevating cylinder 4 to the oil tank 53 so that the pretreatment unit 3 is lowered by the reduction operation of the elevating cylinder 4; It is configured to be switchable to a stop position at which the supply / discharge of hydraulic oil to / from the lifting cylinder 4 is stopped so that the lifting / lowering of the pretreatment unit 3 is stopped by stopping the expansion / contraction operation.

  The deceleration turn valve 57 has a connection position that forms a flow path for supplying hydraulic oil from the hydraulic pump 54 to the deceleration turn clutch 42a and the deceleration turn clutch 42a is disconnected so that the deceleration turn clutch 42a is connected. Thus, the position can be switched to a cutting position that forms a flow path for discharging the hydraulic oil in the deceleration turn clutch 42 a to the oil tank 53.

  Each of the pair of horizontal valves 58 supplies hydraulic oil from the hydraulic pump 54 to the extension chamber 31a of the horizontal cylinder 31 so that the horizontal cylinder 31 side of the traveling machine body 3 is raised by the extension operation of the horizontal cylinder 31. The horizontal cylinder of the traveling machine body 3 is formed by a rising position that forms a flow path for discharging the hydraulic oil in the reduction chamber 31b of the horizontal cylinder 31 to the oil tank 53 and a reduction operation of the horizontal cylinder 31. A flow path for supplying hydraulic oil from the hydraulic pump 54 is formed in the reduction chamber 31 b of the horizontal cylinder 31 so as to lower the 31 side, and the hydraulic oil in the extension chamber 31 a of the horizontal cylinder 31 is supplied to the oil tank 53. Due to the lowered position that forms the discharge flow path and the extension stop of the horizontal cylinder 31, the elevation of the traveling machine body 3 on the side of the horizontal cylinder 31 is stopped. Sea urchin, are positioned switchably configured to a stop position to stop the supply and discharge of hydraulic oil to the horizontal cylinder 31.

  Each of the pair of drive valves 59 has a connection position that forms a flow path for supplying hydraulic oil from the hydraulic pump 54 to the drive clutch 48 so that the drive clutch 48 is connected, and the drive clutch 48 is disconnected. Thus, the position of the hydraulic oil in the drive clutch 48 can be switched to a cutting position that forms a flow path for discharging the hydraulic oil to the oil tank 53.

  Since the drive valve 59 is a proportional control valve, it is possible to switch the intermittent state of the drive clutch 48 step by step, so that the ratio of the power of the switching shaft 44 to the drive shaft 49 is increased. You can finely change and adjust the transmission.

  The auger elevating valve 61 is an ascending position that forms a flow path for supplying hydraulic oil from the hydraulic pump 54 to the extension chamber 13a of the auger elevating cylinder 13 so that the auger 9 is raised by the extension operation of the auger elevating cylinder 13. A lowering position for forming a flow path for discharging the hydraulic oil in the extension chamber 13a of the auger lifting cylinder 13 to the oil tank 53 so that the auger 9 is lowered by the reduction operation of the auger lifting cylinder 13; In order to stop the raising / lowering of the auger 13 by stopping the expansion / contraction operation of 13, the position can be switched to the stop position where the supply / discharge of the hydraulic oil to the auger raising / lowering cylinder 13 is stopped.

  The side clutch valve 63 includes a left turning position that forms a flow path for operating the side clutch cylinder 62 so that the left side clutch 47 is disconnected and the right side clutch 47 is connected, and the left side clutch 47 is A right turn position that forms a flow path for operating the side clutch cylinder 62 so that the right side clutch 47 is disconnected, and a side clutch cylinder 62 that connects the left and right side clutches 47, 47 are connected. The position is switchable to a straight-ahead position that forms a flow path to be operated.

  FIG. 5 is a plan view of the control unit in the cabin. The control unit 6 in the cabin 7 is disposed on the opposite side of the entrance 6a with the seat 64 on which an operator is seated, a multi-lever (steering lever) 66 disposed in front of the seat 64, and the seat 64 in plan view. A main transmission lever 67, a sub transmission lever 68 disposed on the outer side of the main transmission lever 67, and an operation panel 69 disposed behind the main transmission lever 67.

  The main transmission lever 67 can swing forward from the neutral position by setting the swing position where the above-mentioned HST 33 is neutral to the neutral position and inclining to the left or right side (right side in the illustrated example) at the neutral position. On the other hand, it is possible to swing backward from the neutral position by inclining left and right in the neutral position. Then, by swinging the main speed change lever 67 forward from the neutral position, the HST 33 is accelerated to the forward travel side, while the main speed change lever 67 is swung backward from the neutral position to move backward. The HST 33 is speeded up on the traveling side.

  The auxiliary transmission lever 68 switches the auxiliary transmission mechanism 38 to a high speed state or a low speed state by swinging back and forth.

  The multi-lever 66 is mounted and supported on the steering unit 6 so as to be swingable back and forth and swingable left and right. The multi-lever 66 is swung back and forth from the neutral position to move the pre-processing unit 3 up and down, and the multi-lever 66 is swung left and right from the neutral position to turn the traveling machine body 2 left and right. Direction operation.

  FIG. 6 is an explanatory view showing an operation state according to the left and right inclination angles of the multi-lever. When the multi-lever 66 is swung from the neutral position N to the left-right most tilted position E, the operation position (left-right inclination angle) of the multi-lever 66 is the brake off position P1, the turning operation position P2, and the detent position P3. → Displacement is made in the order of the switching position P4, and finally the position E is reached most. In other words, the left and right swinging ranges of the multi-lever 66 are arranged in order from the neutral position N in the order of the brake off position P1, the turning operation position P2, the detent position P3, the switching position P4, and the most tilted position E. Are provided. Incidentally, in the following description, it is assumed that the switching mechanism 43 is switched to the deceleration turning state.

  When the multi-lever 66 is swung between the neutral position N and the brake off position P1, the turning mechanism 42 is in a braking state via the deceleration turn clutch 42a, and both sides are connected via the side clutch cylinder 62. The clutches 47 and 47 are in a connected state (a straight traveling state).

  When the multi-lever 66 is swung between the brake-disengaged position P1 and the turning operation position P2, the turning mechanism 42 is in a transmission state via the deceleration turn clutch 42a, and both are connected via the side clutch cylinder 62. The side clutches 47 and 47 are in a connected state (a straight traveling state).

  When the multi-lever 66 is swung between the turning operation position P2 and the switching position P4, the turning mechanism 42 is in a transmission state via the deceleration turn clutch 42a, and via the left and right side clutch cylinders 62. The side clutch 47 on the swinging side (turning side) of the multi-lever 66 is switched to the disconnected state, and the non-swinging side (non-turning side) of the multilever 66 is switched to the connected state, so that the above-described reduced-swing mode is set. .

  When the multi-lever 66 is swung between the switching position P4 and the most tilted position E, the turning mechanism 42 is in a braking state via the deceleration turn clutch 42a, and the multi-lever 66 is The side clutch 47 on the swinging side (turning side) of the lever 66 is switched to the disconnected state, and the non-swinging side (non-turning side) of the multi-lever 66 is switched to the connected state, and the above-described brake swing mode is set.

  That is, the range closer to the neutral position N than the switching position P4 is a deceleration turning range in which the traveling machine body 2 is turned left and right by the deceleration turning control, and the range closest to the position E from the switching position P4 is the brake turning range. This combine is comprised so that it may become the brake turning range which makes the traveling body 2 turn left and right by turning control.

  In addition, the light operation range that is closer to the neutral position N than the detent position P3 swings the multi-lever 66 left and right with a lighter operating force than the heavy operation range that is closest to the position E than the detent position P3. The multi-lever 66 is supported by the steering unit 6 so that it can be moved.

  Incidentally, at the time of the deceleration turning control and the brake turning control, as described above, the turning-side drive clutch 48 is in a connected state and the non-turning-side drive clutch 48 is in a disconnected state. However, as the left / right swinging position of the multi-lever 66 moves away from the neutral position N (as the left / right tilt angle of the multi-lever 66 increases), the lower-speed power is transmitted to the crawler type traveling device 1 on the turning side. (The pressure of the drive valve 59 is increased), thereby increasing the speed difference from the crawler type traveling device 1 on the non-turning side and increasing the change angle (steering angle) of the running direction during turning.

  That is, the greater the left / right tilt angle of the multi-lever 66, the steerable vehicle body 2 is steered at a larger steering angle. The rate of increase of the steering angle with the increase of the left / right tilt angle is from the detent position P3 to the neutral position N. The range from the detent position P3 to the most tilted position E is set to be larger than the range up to.

  As a result, the left and right light operation ranges on the side close to the neutral position N are directions in which the direction correction control for finely adjusting the traveling direction of the traveling machine body 2 is performed when the multi-lever 66 is swung to the range. On the other hand, the left and right heavy operation ranges on the far side from the neutral position N are the turning ranges that perform turning control that causes the traveling machine body 2 to turn left and right greatly when the multi-lever 66 is swung to the range. The combine is configured to be in range. Incidentally, during the execution of the turning control, the traveling aircraft body 2 is steered more rapidly with a larger steering angle in the brake turning mode than in the above-described reduced speed turning mode.

  FIG. 7 is a plan view of the operation panel. The operation panel 69 includes a work implement clutch switch 71 which is an intermittent operation tool for performing intermittent operation of the work implement clutch for performing intermittent operation of engine power to the preprocessing unit 3 and the threshing device, and horizontal automatic control which is a kind of tilt control. There is provided a horizontal automatic switch 72 which is an on / off operation tool for performing the on / off operation.

  Incidentally, at the time of tilt control, the left and right lifting mechanisms 23, 23 cause the traveling machine body 2 to be tilted left and right (rolling operation) with respect to the left and right crawler-type traveling devices 1, 1, and the unevenness and inclination of the farm scene and the road surface. Regardless of, the traveling machine body 2 is held at a predetermined left-right inclination angle predetermined with respect to the horizontal direction. In particular, when performing horizontal automatic control, which is a type of tilt control, the predetermined tilt angle is 0 degree, and the traveling machine body 2 is held horizontally in the left-right direction regardless of the tilt of the traveling surface. The

  This tilt control is executed by a control unit (see FIG. 8) 73 composed of a microcomputer or the like mounted on the combine. Incidentally, the steering operation of the traveling machine body 2 shown in FIG. 6 may be controlled by the control unit 73, or the steering operation may be controlled by a microcomputer or the like provided separately from the control unit 73. However, the steering operation may be controlled by combining a relay circuit, a sensor, and the like.

  FIG. 8 is a block diagram of the control unit. On the input side of the control unit 73, in addition to the work implement clutch switch 71 and the horizontal automatic switch 72 described above, a tilt sensor (tilt detection means) 74 that detects the left and right tilt angles of the traveling machine body 2 with respect to the horizontal direction, and the branch described above. An operation for detecting a left-right swinging position by detecting a left-right inclination angle of the multi-lever 66 and a vehicle speed sensor 76 that is a traveling speed detecting means for detecting the traveling speed of the traveling machine body 2 by detecting the rotational speed of the shaft 39. A multi-lever potentiometer 77 which is a position detecting means is connected.

  On the output side of the control unit 73, a horizontal valve that is a solenoid that raises the right side of the traveling machine body 2 by switching the horizontal valve 58 that expands and contracts the horizontal cylinder 31 installed in the crawler type traveling device 1 on the right side to the raised position. A right raising means 78, a horizontal valve lowering means 79 which is a solenoid for lowering the right side of the traveling machine body 2 by switching the horizontal valve 58 to a lowered position, and a horizontal cylinder installed in the crawler type traveling device 1 on the left side. By switching the horizontal valve 58 for expanding and contracting 31 to the raised position, the horizontal valve left raising means 81 which is a solenoid for raising the left side of the traveling machine body 2 and the horizontal valve 58 to the lowered position, A horizontal valve lowering means 82 which is a solenoid for lowering the left side is connected.

  When the traveling machine body 2 is steering during execution of the horizontal automatic control, the control unit 73 restricts the execution of the horizontal automatic control under a predetermined condition. Specifically, when the multi-lever 66 during the steering operation is swung to a non-regulatory range that is closer to the neutral position N than the detent position P3, while the execution of the horizontal automatic control is continued, The control unit 73 is configured to stop the execution of the horizontal automatic control when the multi-lever 66 during the steering operation is swung to the restriction range which is the most tilted position from the detent position P3 and closer to the position EN. ing.

  That is, the direction correction range and the light operation range set to the same range are set to a non-restricted range that does not restrict the execution of horizontal automatic control, and the turning range and heavy operation range set to the same range are It is set to a regulation range that regulates execution of control.

  FIG. 9 is a process flow diagram of horizontal automatic control performed by the control unit. When the process is started, the control unit 73 proceeds to step S1. In step S1, on / off detection of the horizontal automatic switch 72 is performed, and when the on / off operation is performed, it is assumed that the horizontal automatic control is being executed or is in an executable state, and the process proceeds to step S2. In step S2, the on / off detection of the work implement clutch switch 71 is performed to detect the on / off state of the work implement clutch, and when the transmission of engine power to the preprocessing unit 3 and the threshing device is connected, the cutting / threshing operation is being performed. As such, the process proceeds to step S3.

  In step S3, the left / right operation position of the multi-lever 66 is detected by the multi-lever potentiometer 77. If the multi-lever 66 is located in either the left / right unrestricted range or the neutral position N, the traveling machine body 2 travels straight. Or the traveling direction of the traveling machine body 2 is identified as being finely adjusted, and the process proceeds to step S4. On the other hand, if the multi-lever 66 is located in either the left or right regulation range, the traveling machine body 2 is larger. It identifies that it is turning right and left, and progresses to step S5.

  In step S4, the steering operation is a fine adjustment of the traveling direction, and the traveling vehicle body 2 is stable to the extent that it can be tilted to the left and right. Therefore, in order to continue the tilt control, a tilt determination subroutine is executed. When this subroutine ends, the process returns to step S1. On the other hand, in step S5, it is determined that the traveling vehicle body 2 that has been swung left and right is not stable to the extent that it can be tilted left and right, and a valve stop subroutine is executed to temporarily stop the tilt control. When this subroutine ends, the process returns to step S1. Incidentally, in the valve stop subroutine, the pair of horizontal valves 58 and 58 are held in a state of being switched to the stop positions, and the expansion and contraction of the left and right horizontal cylinders 31 and 31 is stopped.

  In step S1, when the horizontal automatic switch 72 is turned on, it is assumed that execution of horizontal automatic control is stopped, and the process proceeds to step S5. Moreover, in step S2, when the transmission of the engine power to the preprocessing unit 3 and the threshing device is cut off from the on / off detection of the work machine clutch switch 71, it is assumed that no mowing / threshing work is performed. The process proceeds to step S5. By the way, by performing horizontal automatic control during the threshing operation, the threshing device is held substantially horizontal regardless of the unevenness or inclination of the field scene, and the threshing / sorting operation can be performed efficiently.

  FIG. 10 is a processing flow diagram of a subroutine for tilt determination. When the processing of the tilt determination subroutine is started, the control unit 73 proceeds to step S11. In step S11, the traveling speed of the traveling machine body 2 is detected by the vehicle speed sensor 76. When the traveling speed is slower than the threshold speed X that is a predetermined speed, the process proceeds to step S12 while the traveling speed is the threshold speed. If it is faster than X, the process proceeds to step S13.

  In step S12, the low value x is substituted for the slope detection dead zone value and the process proceeds to step S14, while in step S13, the high value y is substituted for the slope detection dead zone value and the process proceeds to step S14. Incidentally, the low value x is set to a lower value than the high value y. In step S14, the inclination sensor 74 detects the horizontal inclination angle of the traveling machine body 2 with respect to the horizontal direction. If the detected horizontal inclination angle is equal to or greater than the inclination detection dead zone value, the process proceeds to step S15.

  In step S15, a subroutine for operating valve determination is executed, and when the processing of the subroutine ends, the process proceeds to step S16.

  In the operation valve determination subroutine, based on the left-right tilt state of the traveling machine body 2, it is selected whether to operate the left or right horizontal cylinders 31, 31 in order to make the left-right inclination of the traveling machine body 2 horizontal. A determination is made as to whether the horizontal cylinder 31 is operated to extend or contract. For example, when the traveling machine body 3 is inclined downward to the left or right side, the horizontal cylinder 31 arranged in the one side crawler type traveling device 1 is extended or the other side crawler type traveling device is operated. One horizontal cylinder 31 is contracted. Incidentally, when making this determination, it may be considered that the traveling machine body 2 has as low a center of gravity as possible.

  In step S16, a valve actuation subroutine for actuating the valve is executed based on the matters determined by the subroutine execution of the actuation valve decision. When this processing is completed, this inclination determination subroutine processing is terminated.

  In step S14, when the horizontal inclination angle with respect to the horizontal direction of the traveling machine body 2 is smaller than the inclination detection dead zone value, the process proceeds to step S17. In step S17, the horizontal inclination angle of the traveling machine body 2 with respect to the horizontal direction is smaller than the inclination detection dead zone value, and it can be determined that the traveling machine body 2 is in a substantially horizontal state. The left / right tilt operation is stopped, and the tilt determination subroutine is terminated.

  As described above, when the horizontal inclination angle of the traveling machine body 2 with respect to the horizontal direction is smaller than the inclination detection dead band value, the left and right inclination operation of the traveling machine body 2 with respect to the horizontal direction is stopped. When the inclination detection dead zone value is equal to or greater than the value, the left and right tilting operation of the traveling machine body 2 is stopped. Therefore, the occurrence of hunting that causes the traveling machine body 2 to vibrate by repeating the left and right tilting operation in a substantially horizontal state is efficiently performed. Can be prevented.

  Further, when the traveling speed is slower than the threshold speed X, a low value x is substituted for the inclination detection dead band value, and when the traveling speed is higher than the threshold speed X, a high value y is substituted for the inclination detection dead band value. Therefore, when the traveling speed is traveling at a high speed, the tilt detection dead zone value becomes large, and unless the traveling aircraft body 2 tilts further to the left and right, the traveling aircraft body 2 does not operate to tilt left and right. Hunting can be prevented.

  FIG. 11 is a processing flowchart of a subroutine for valve operation. When the process of the valve actuation subroutine is started, the control unit 73 advances the process to step S21. In step S21, the traveling speed is detected by the vehicle speed sensor 76. If the detected traveling speed is slower than the threshold speed X, the process proceeds to step S22. If the detected traveling speed is higher than the threshold speed X, the process proceeds to step S23. . Incidentally, although the threshold speed X shown in the figure is set to be the same as the threshold speed X shown in FIG. 10, both may be set to different values.

  In step S22, the raising ON time, which is the time for extending the horizontal cylinder 31 and continuously raising the corresponding side of the traveling machine body 2, and the horizontal cylinder 31 is reduced and the corresponding side of the traveling machine body 2 is continuously lowered. Both the lower ON time, which is time, is set to time a, and the process proceeds to step S24. In step S23, while raising ON time is set to time b, decreasing ON time is set to time c, and it progresses to step S24. Incidentally, the time b is set shorter than the time a, and the time c is set shorter than the time b.

  In step S24, a check is made to see if the valve operation timer, which is a timer built in the control unit 73, has reached 0 and the count has ended. If the count has ended, the process proceeds to step S25, where the count is increased. If not completed, the process proceeds to step S26. In step S25, time a is set in the valve operation timer, the countdown to 0 is started again, and the process proceeds to step S26.

  In step S26, the operation valve determination subroutine is checked. If the operation direction of the horizontal cylinder 31 selected by the operation valve determination is determined to be on the side where the traveling machine body 2 is raised, the process proceeds to step S27. In step S27, when the valve operation timer is not less than the time obtained by subtracting the increase ON time from time a due to the countdown, the process proceeds to step S28. In step S28, the selected horizontal cylinder 31 is extended by the solenoids 78, 79, 81, 82, and the valve operation subroutine is terminated. In step S27, when the valve operation timer is equal to or less than the time obtained by subtracting the raising ON time from time a due to the countdown, the horizontal cylinder 31 is not extended and the valve operation subroutine is terminated.

  If it is determined in step S26 that the operating direction of the horizontal cylinder 31 selected by the operating valve determination subroutine is determined to be the side for lowering the traveling machine body 2, the process proceeds to step S29. In step S29, if the valve operation timer is not equal to or less than the time obtained by subtracting the decrease ON time from time a due to the countdown, the process proceeds to step S30. In step S30, the selected horizontal cylinder 31 is contracted by the solenoids 78, 79, 81, and 82, and the valve operation subroutine is terminated. In step S29, if the valve operation timer is equal to or less than the time obtained by subtracting the lowering ON time from the time a due to the countdown, the horizontal cylinder 31 is not reduced and the valve operation subroutine is terminated.

  Since the main routine shown in FIG. 9 is repeatedly executed, the valve operation subroutine is also repeatedly executed when the traveling machine body 2 is tilted left and right. In the repeated execution of the valve operation subroutine, the valve operation timer starts to count down from the time a every time a by step S24 and step S25.

  When the corresponding part of the traveling machine body 2 is raised within this time a, the selected horizontal cylinder 31 is extended until the raising ON time elapses, and after the raising ON time elapses, the selected The extension operation of the horizontal cylinder 31 is stopped. On the other hand, when the corresponding part of the traveling machine body 2 is lowered within this time a, the selected horizontal cylinder 31 is reduced before the lowering ON time elapses, and after the lowering ON time elapses, the selection is performed. The reduction operation of the horizontal cylinder 31 is stopped.

  When the traveling machine body 3 is traveling at a speed slower than the threshold speed X, both the raising ON time and the lowering ON time are set to the time a. Sometimes the corresponding horizontal cylinder is driven continuously.

  On the other hand, when the traveling machine 3 is traveling at a speed equal to or higher than the threshold speed X, the time b, which is a time shorter than the time a, becomes the ON time, and the time c, which is a time shorter than the time a, It becomes lower ON time. For this reason, the corresponding horizontal cylinder is intermittently driven when the traveling body 2 is tilted left and right during the tilt control. Specifically, the horizontal cylinder 31 is driven by b / a in one circumference during expansion, and the horizontal cylinder 31 is driven by c / a in one circumference during reduction.

  That is, when the traveling speed becomes higher than the threshold speed, the driving speed of the left and right tilting operation of the traveling machine body 2 at the time of tilt control is lowered, and this makes it possible to more efficiently prevent the hunting at the time of high speed traveling. .

Next, based on FIG. 12, a different point from the above-mentioned example is demonstrated about another embodiment of this invention.
FIG. 12 is a process flow diagram illustrating another embodiment of the horizontal automatic control performed by the control unit. As shown in the processing content of step S3 in the same figure, the light operation range is set to the non-restriction range, and the heavy operation range is set to the restriction range.

  In the example shown in FIGS. 1 to 11, the light operation range is set to the same range as the direction correction range, and the heavy operation range is set to the same range as the turning range. As a result, the control content shown in FIG. Is the same as that shown in FIG.

Next, based on FIG. 13, a different point from the above-mentioned example is demonstrated about another embodiment of this invention.
FIG. 13 is a process flow diagram showing another embodiment of the horizontal automatic control performed by the control unit. As shown in the processing content of step S3 in the figure, the deceleration turning range is set to the non-restricted range, and the brake turning range is set to the restricted range.

1 Crawler type traveling device (traveling device)
DESCRIPTION OF SYMBOLS 1a Traveling frame 2 Traveling machine body 2a Airframe frame 3 Pre-processing part 4 Lifting cylinder (hydraulic cylinder)
4a Extension chamber 6 Control section 7 Cabin 8 Glen tank 8a Transport spiral 9 Auger 11 Vertical cylinder 11a Transport spiral 12 Discharge cylinder 12a Transport spiral 13 Auger lifting cylinder (hydraulic cylinder)
13a Extension chamber 14 Roller wheel 16 Idler wheel 17 Drive sprocket (drive wheel)
18 Upper wheel (roller)
19 Movable wheels (rollers)
21 Crawler 22 Support arm 23 Elevating mechanism 24 Link 26 Link 27 Main arm 28 Subordinate arm 29 Connecting rod 31 Horizontal cylinder (tilt drive means, hydraulic cylinder)
31a Extension chamber 31b Reduction chamber 32 Engine 33 HST (hydraulic continuously variable transmission)
34 Transmission 36 Transmission case 37 Traveling shaft 38 Subtransmission mechanism 38a High speed gear 38b Low speed gear 38c Shifter member 39 Branch shaft 41 Intermediate shaft 42 Turning mechanism 42a Deceleration turn clutch 42b Brake turn clutch 43 Switching mechanism 43a Deceleration turning gear 43b Spin turning gear 43c Shifter member 44 Switching shaft 46 Cylindrical transmission shaft 47 Side clutch 48 Drive clutch 49 Drive shaft 51 Rotating transmission shaft 52 Hydraulic device 53 Oil tank 54 Hydraulic pump 56 Lift valve (solenoid valve)
57 Deceleration turn valve (solenoid valve)
58 Horizontal valve (solenoid valve)
59 Drive valve (proportional control valve)
61 Auger lift valve (solenoid valve)
62 Side clutch cylinder 63 Side clutch valve (solenoid valve)
64 seats 66 multi-lever (steering lever)
67 Main transmission lever 68 Sub transmission lever 69 Operation panel 71 Work implement clutch switch (intermittent operation tool)
72 Horizontal automatic switch (on / off operation tool)
73 Control unit (microcomputer)
74 Tilt sensor (Tilt detection means)
76 Vehicle speed sensor (travel speed detection means, rotation sensor)
77 Multi-lever potentiometer (operation position detection means)
78 Horizontal valve lifting mechanism (solenoid)
79 Horizontal valve lowering means (solenoid)
81 Horizontal valve left raising means (solenoid)
82 Horizontal valve lowering means (solenoid)
E E most tilted position N Neutral position P1 Brake off position P2 Turning operation position P3 Detent position P4 Switching position

Claims (4)

Inclination drive means (31), (31) for operating the traveling body (2) supported by the pair of left and right traveling devices (1), (1) to the left and right traveling devices (1), (1). ) And an inclination detection means (74) for detecting the left-right inclination of the traveling machine body (2), and based on the detection result of the inclination detection means (74), the inclination drive means (31), (31) , A work vehicle provided with a control unit (73) that executes tilt control for holding the traveling machine body (2) at a predetermined left and right tilt angle with respect to the horizontal direction, the left and right sides from the neutral position (N) a steering lever (66) to perform the steering operation by the swinging operation position detecting means for detecting a lateral swing position from the neutral position of the該操direction lever (66) (N) (77) is provided, the operation The position detection means (77) is a neutral position (N) of the steering lever (66). Detects a non-regulation range that is a range closer to the neutral position (N) in each of the left and right swing ranges and a control range that is a range farther from the neutral position (N) in each of the left and right swing ranges. and configurable, the control unit (73), when said operation position detecting means (77) by the steering lever (66) is swung in any of regulation range right is detected, the inclination While the execution of the control is stopped, the steering lever (66) is swung to the left or right non-restricted range by the operation position detecting means (77) , or is swung to the neutral position (N). If this is detected, the work vehicle continues to execute the tilt control.   When the operation position detecting means (77) detects that the steering lever (66) is swung to either the left or right regulation range, the control unit (73) controls the steering lever (66). ), The steering lever (66) is swung to either the left or right unrestricted range by the operation position detecting means (77). When it is detected that the vehicle has been detected, direction correction control for steering the traveling vehicle body (2) by a predetermined angle smaller than that during turning control is performed on the swing side of the steering lever (66). The work vehicle described.   The work vehicle according to claim 1, wherein the steering lever (66) is configured such that a left-right swinging operation can be performed with an operation force lighter than that in the non-regulated range.   When the operating position detecting means (77) detects that the steering lever (66) is swung to either the left or right non-restricted range, the controller (73) While performing the decelerating turning control for decelerating the traveling device (1) to a driving speed slower than the non-oscillating traveling device (1), the steering lever (66) is moved by the operation position detecting means (77). 2. The work vehicle according to claim 1, wherein, when it is detected that the vehicle has swung within one of the left and right regulation ranges, brake work control is performed to brake the rocking side travel device.

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