JP2013085491A - Working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of the ride comfort of a traveling machine body decreasing as inclination control is continued if the inclined attitude of the traveling machine body is changed suddenly by the inclination of a field face or the like or by vibration or the like during travel during the execution of the inclination control of the traveling machine body, or if a sensor for detecting inclination angles detects excessively.SOLUTION: This working vehicle includes: a traveling machine body 1 supported by right and left traveling parts 2; a pair of rolling actuators 38 for varying the horizontal inclined attitude of the traveling machine body 1; a pair of pitching actuators 177 for varying the vertical inclined attitude of the traveling machine body 1; a horizontal inclination sensor 374 for detecting the horizontal inclination angle of the traveling machine body 1; and a longitudinal inclination sensor 381 for detecting the longitudinal inclination angle of the traveling machine body 1. During the execution of the horizontal inclination control, if the absolute value |λ(1)-λ(2)| of the difference between the current value λ(2) of the horizontal inclination sensor 374 and the previous value λ(1) of the horizontal inclination sensor 374 exceeds a preset horizontal inclination threshold value Λ, the horizontal inclination control is inhibited.

Description

  The present invention relates to a combine harvester that harvests grains by harvesting cereals planted in a field, a feed combine that harvests grains for feed and collects them as feed, or a work vehicle such as a transport vehicle that travels on rough terrain. More particularly, the present invention relates to a work vehicle having a traveling unit such as a pair of left and right traveling crawlers.

  Conventionally, a combine that is an example of a work vehicle includes a traveling machine body supported by left and right traveling units, and a pair of left and right vehicle height adjusting hydraulic cylinders as rolling actuators that change the inclined posture of the traveling machine body in the left-right direction; A pair of left and right hydraulic cylinders for front / rear tilting as a pitching actuator for changing the tilting posture of the traveling machine body in the front / rear direction is provided. In this type of combine, a technique for tilting the traveling machine body in the front-rear and left-right directions by the expansion and contraction of the four hydraulic cylinders is known (see, for example, Patent Documents 1 and 2). In this case, the traveling machine body moves up and down by the expansion and contraction of both the vehicle height adjusting hydraulic cylinders. Further, the traveling machine body is tilted left and right by the expansion and contraction of each vehicle height adjusting hydraulic cylinder, and the traveling machine body is tilted back and forth by the expansion and contraction movement of both the front and rear tilting hydraulic cylinders.

Japanese Utility Model Publication No. 6-28387 JP 2000-106740 A

  By the way, in the prior art, during the execution of the tilt control for changing the tilt posture in the front / rear / left / right direction for the purpose of maintaining the horizontal posture of the traveling machine body to the ground, the vehicle travels by the inclination of the farm scene or the vibration of the traveling machine body during the traveling. In some cases, the tilt posture of the airframe changes suddenly or the sensor for detecting the tilt angle detects excessively. If the tilt control is continued in such a state, there is a problem in that the traveling aircraft body is excessively changed in posture in the front-rear or left-right direction (hunting motion), and the riding comfort of the traveling aircraft body is deteriorated.

  The present invention has been made as a technical problem to provide a work vehicle that has been improved by examining the above-described present situation.

  According to a first aspect of the present invention, a traveling machine body supported by left and right traveling units, a pair of rolling actuators for changing a lateral inclination posture of the traveling aircraft body, and a longitudinal inclination posture of the traveling aircraft body are changed. A work vehicle comprising a pair of pitching actuators, a left / right tilt sensor that detects a tilt angle in the left / right direction of the traveling machine body, and a front / rear tilt sensor that detects a tilt angle in the front / rear direction of the traveling machine body, During the execution of the left / right tilt control for changing the left / right tilt posture of the traveling machine body, if the absolute value of the difference between the current left / right tilt sensor value and the immediately preceding left / right tilt sensor value exceeds a preset left / right tilt threshold, It is configured to prohibit right / left tilt control.

  According to a second aspect of the present invention, in the work vehicle according to the first aspect, after the absolute value of the difference once exceeds the left-right inclination threshold, a state in which the absolute value of the difference is lower than the left-right inclination threshold is preset. In addition, when the first set time has passed, it is configured to return to the execution state of the left-right tilt control.

  According to a third aspect of the present invention, in the work vehicle according to the first or second aspect, during the execution of the front / rear tilt control for changing the front / rear tilt posture of the traveling machine body, the current front / rear tilt sensor value and the front / rear tilt sensor immediately before When the absolute value of the difference from the value exceeds a preset forward / backward tilt threshold, the forward / backward tilt control is prohibited.

  According to a fourth aspect of the present invention, in the work vehicle according to the third aspect, after the absolute value of the difference once exceeds the front / rear inclination threshold, a state in which the absolute value of the difference falls below the front / rear inclination threshold is preset. In addition, when the second set time has passed, the apparatus is configured to return to the execution state of the front / rear tilt control.

  According to a fifth aspect of the present invention, in the work vehicle according to any one of the first to fourth aspects, the left / right inclination control is prohibited during reverse turning of the traveling machine body.

  According to the invention of claim 1 or claim 3, during the execution of the automatic tilt control for changing the tilt posture of the traveling machine body, the absolute value of the difference between the current tilt sensor value and the previous tilt sensor value is calculated. Since it is configured to prohibit the tilt control when a preset tilt threshold is exceeded, the tilt posture of the traveling machine body suddenly changes due to, for example, the tilt of a farm scene or the vibration of the traveling machine body during traveling. Even if an abrupt change state in which the inclination sensor is excessively detected or the inclination sensor is detected excessively, the inclination control can be prohibited in conjunction with the occurrence of the sudden change state. For this reason, it is possible to prevent the traveling machine body from excessively changing its posture in the front-rear direction (hunting movement), and it is possible to improve the riding comfort of the traveling machine body.

  According to the invention of claim 2 or claim 4, after the absolute value of the difference once exceeds the inclination threshold value, a state in which the absolute value of the difference falls below the inclination threshold value passes a preset time. The inclination control is returned to the execution state, so that even after the inclination control is prohibited due to the occurrence of the sudden change state, if the sudden change state is eliminated, the operator has to take extra effort ( This makes it possible to return to the tilt control automatically and smoothly without applying an operation, thereby reducing the burden on the operator.

  Furthermore, according to the invention of claim 5, since the left / right tilt control is prohibited during reverse turning of the traveling vehicle body, for example, when only the traveling portion on one side rides on a kite or the like during reverse traveling. Even so, the inclined posture of the traveling machine body can be maintained horizontally with respect to the ground, and the workability of the work vehicle can be improved. When such a configuration is applied to, for example, a combine as a work vehicle, it is possible to improve the harvesting and threshing workability with the combine.

It is a side view of the combine for 6-cutting of the embodiment of the present invention. It is the same top view. It is a hydraulic circuit diagram of the combine. It is a side view of a traveling machine body and a traveling crawler part. It is the same top view. FIG. 6 is a top perspective view of FIG. 5. It is side surface explanatory drawing which moved the traveling body up. It is front-lowering side explanatory drawing which moved the traveling body up and inclined forward. It is a crawler attitude | position map which shows the relationship between the ground height of a traveling body, and the front-back inclination angle of a traveling body. It is an operation | movement rule table regarding the combination of a limit range. It is a section explanatory view of the upper surface perspective view of a cabin. It is side surface explanatory drawing of the principal part of a cabin. It is a steering round handle and an enlarged plan view of the periphery. It is a functional block diagram of a control circuit of the attitude control means. It is a flowchart of attitude control. It is a flowchart of the inclination control of the left-right direction and the front-back direction. It is a flowchart of the inclination control at the time of manual operation. It is a flowchart which shows vehicle height raising / lowering control among the inclination control at the time of manual operation. (A) and (b) are explanatory diagrams schematically showing an ascending operation when the load on the left traveling crawler side is large, and (c) and (d) schematically illustrate a descending operation when the load on the left traveling crawler side is large. FIG. It is a flowchart which shows front-back inclination control among the inclination control at the time of manual operation. (A) and (b) are explanatory diagrams schematically showing the forward tilting operation when the load on the left traveling crawler side is large, and (c) and (d) are the backward tilting operations when the load on the left traveling crawler side is large. It is an action explanatory view showing typically. It is a flowchart which shows the sudden change process in right-and-left inclination control. It is a flowchart which shows the sudden change process in front-back inclination control.

  DESCRIPTION OF EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the drawings. FIG. 1 is a left side view of the combine, and FIG. 2 is a plan view of the combine. With reference to FIG.1 and FIG.2, the whole structure of a combine is demonstrated. In the following description, the left side in the forward direction of the traveling machine body 1 is simply referred to as the left side, and the right side in the forward direction is also simply referred to as the right side.

  As shown in FIGS. 1 and 2, a traveling machine body 1 supported by a pair of left and right traveling crawlers 2 as a traveling unit is provided. At the front part of the traveling machine body 1, a 6-row mowing device 3 that takes in while harvesting cereals is mounted by a single-acting lifting hydraulic cylinder 4 so as to be movable up and down around the mowing pivot fulcrum shaft 4 a. The A threshing device 5 having a feed chain 6 and a grain tank 7 for storing the grains taken out from the threshing device 5 are mounted on the traveling machine body 1 side by side. The threshing device 5 is disposed on the left side in the forward direction of the traveling machine body 1, and the grain tank 7 is disposed on the right side in the forward direction of the traveling machine body 1. A swivelable discharge auger 8 is provided at the rear part of the traveling machine body 1, and the grains inside the grain tank 7 are discharged from the throat throwing port 9 of the discharge auger 8 to a truck bed or a container. Yes. An operation cabin 10 is provided on the right side of the cutting device 3 and on the front side of the grain tank 7.

  In the driving cabin 10, a steering round handle 11 as a steering operating tool, a driving seat 12, a main transmission lever 43, an auxiliary transmission switch 44, and a work clutch lever 45 for turning on and off a threshing clutch and a mowing clutch. And are arranged. The driving cabin 10 is provided with a step column 50 (see FIG. 12) on which the operator gets on, a steering column 46 for supporting the steering round handle 11, the lever columns 43, 45, a switch column 44, and the like. 47 are arranged. A diesel engine 14 as a power source is disposed in the traveling machine body 1 below the driver seat 12.

  As shown in FIG. 1, left and right track frames 21 are arranged on the lower surface side of the traveling machine body 1. The track frame 21 includes a drive sprocket 22 that transmits the power of the engine 14 to the traveling crawler 2, a tension roller 23 that maintains the tension of the traveling crawler 2, and a plurality of track rollers that hold the ground side of the traveling crawler 2 in a grounded state. 24 and an intermediate roller 25 that holds the non-grounded side of the traveling crawler 2 are provided. The driving sprocket 22 supports the front side of the traveling crawler 2, the tension roller 23 supports the rear side of the traveling crawler 2, the track roller 24 supports the grounding side of the traveling crawler 2, and the intermediate roller 25 supports the non-traveling crawler 2. Support the ground side.

  As shown in FIGS. 1 and 2, below the cutting frame 221 connected to the cutting rotation fulcrum shaft 4 a of the cutting device 3, a clipper that cuts the stock of uncut grain cereal (grain culm) planted in the field. A type of cutting blade device 222 is provided. In front of the mowing frame 221, a stalk raising apparatus 223 for six stalks that raises an uncut cereal cultivated in the field is disposed. Between the culm pulling device 223 and the front end (feed start side) of the feed chain 6, a culm conveying device 224 that conveys the chopped culm harvested by the cutting blade device 222 is arranged. In addition, in front of the lower part of the cereal habit raising device 223, a weeding body 225 for 6 strips for weeding uncut cereal cereals is projected. While moving in the field, the reaping device 3 continuously cuts uncut cereal grains planted in the field.

  Next, with reference to FIG.1 and FIG.2, the structure of the threshing apparatus 5 is demonstrated. As shown in FIGS. 1 and 2, the threshing device 5 includes a handling cylinder 226 for threshing threshing, a rocking sorter 227 that sorts the cereals falling below the handling cylinder 226, and a tang fan 228. A processing cylinder 229 that reprocesses the threshing waste taken out from the rear part of the cylinder 226 and a dust exhaust fan 230 that discharges dust at the rear part of the swing sorter 227 are provided. In addition, the cereals conveyed by the culm conveying device 224 from the reaping device 3 are inherited by the feed chain 6, carried into the threshing device 5, and threshed by the handling cylinder 226.

  As shown in FIG. 1, on the lower side of the rocking sorter 227, there are a first conveyor 231 for taking out the grain (first thing) sorted by the rocking sorter 227 and two branches such as a grain with a branch raft. A second conveyor 232 for taking out the articles is provided. The rocking sorter 227 is configured such that threshing that has leaked from the receiving net 237 stretched below the handling cylinder 226 is rocked and sorted (specific gravity sorting) by the feed pan 238 and the chaff sheave 239. . The grain that has fallen from the rocking sorter 227 is removed by the sorting air from the red pepper fan 228 and the dust in the grain falls first on the conveyor 231. The grain taken out first from the conveyor 231 is carried into the grain tank 7 via the cereal conveyor 233 and collected in the grain tank 7.

  Further, as shown in FIG. 1, the swing sorter 227 is configured to drop a second thing such as a grain with a branch incline from the chaff sheave 239 onto the second conveyor 232 by swing sorting. A sorting fan 241 for wind-selecting the second thing falling below the chaff sheave 239 is provided. As for the second thing that has fallen from the chaff sheave 239, the dust and swarf in the grain are removed by the sorting air from the sorting fan 241 and dropped onto the second conveyor 232. The terminal end of the second conveyor 232 is connected to the upper surface side of the rear part of the feed pan 238 via the reduction conveyor 236, and is configured to return the second product to the upper surface side of the swing sorter 227 for re-sorting. doing.

  On the other hand, as shown in FIGS. 1 and 2, an exhaust chain 234 and an exhaust cutter 235 are disposed on the rear end side (feed end side) of the feed chain 6. The slag passed from the rear end side of the feed chain 6 to the sewage chain 234 (the slag from which the grain has been threshed) is discharged to the rear of the traveling machine body 1 in a long state, or the rear part of the threshing device 5 After being cut to an appropriate length by a waste cutter 235 provided on the rear, the paper is discharged to the lower rear side of the traveling machine body 1.

  Next, the hydraulic circuit structure of the combine will be described with reference to FIG. As shown in FIG. 3, the combine hydraulic circuit 250 raises and lowers the above-described lifting hydraulic cylinder 4, an auger lifting hydraulic cylinder 254 that raises and lowers the side of the discharge auger 8 and the left and right ends of the traveling machine body 1. Left and right vehicle height adjustment hydraulic cylinders 38 as rolling actuators that tilt the traveling machine body 1 left and right, and left and right front and rear tilts as pitching actuators that tilt the traveling machine body 1 forward and backward by raising and lowering the front and rear parts of the traveling machine body 1. The hydraulic cylinder 177 for operation and each work pump 91a, 91b of a double structure are provided. A first high-pressure oil passage 257 is connected to the discharge side of one work pump 91a. A second high pressure oil passage 258 is connected to the discharge side of the other work pump 91b.

  The first high pressure oil passage 257 is connected to a cutting lift electromagnetic valve 260 that operates the lifting hydraulic cylinder 4 and an unload relief valve 256 for the tank oil passage. Comparison of the lifting / lowering solenoid valve 260 for moving the cutting device 3 at a relatively high speed, the lifting / lowering solenoid valve 264 for moving the cutting device 3 at a relatively low speed, and the lifting / lowering hydraulic cylinder 4 on the lowering side of the cutting device 3 A cutting lowering solenoid valve 265 that operates at a low speed is connected to the lifting hydraulic cylinder 4. Separately from the lifting / lowering movement of the cutting / lifting electromagnetic valve 260 for switching the cutting / lifting electromagnetic valve 260, the cutting / lifting electromagnetic valve 264 is switched to raise the cutting apparatus 3. While being limited by the mowing lift electromagnetic valve 264, the mowing apparatus 3 is lowered by switching the mowing lowering electromagnetic valve 265.

  The second high-pressure oil passage 258 includes a left tilt solenoid valve 261 that operates the left vehicle height adjustment hydraulic cylinder 38, a right tilt solenoid valve 262 that operates the right vehicle height adjustment hydraulic cylinder 38, and a left front / rear tilt hydraulic cylinder. A left-hand front tilting solenoid valve 266 that operates 177, a right-hand front tilting solenoid valve 267 that operates the right-hand front tilting hydraulic cylinder 177, and a grain discharge solenoid valve 263 that operates the auger lifting hydraulic cylinder 254 are connected. Has been. Further, a left tilting solenoid valve 261, a right tilting solenoid valve 262, a left side front / rear tilting solenoid valve 266, a right side front / rear tilting solenoid valve 267, and a grain discharge solenoid valve 263 are arranged via a posture control solenoid valve 268. 2 is connected to the high pressure oil passage 258. The posture control solenoid valve 268 gives priority to the operation of the auger lifting hydraulic cylinder 254 over the operation of the vehicle height adjusting hydraulic cylinder 38 or the front / rear tilt hydraulic cylinder 177. A relief valve 269 is connected in parallel to the attitude control electromagnetic valve 268.

  Next, a structure for adjusting the tilt angle in the left-right direction of the traveling machine body 1 will be described with reference to FIGS. 4 to 8, a pair of left and right rolling fulcrum frames 26 provided on the lower surface side of the traveling machine body 1, a pair of left and right front bearing bodies 27, and a pair of left and right rear bearing bodies 28 are provided. A pair of left and right front bearing bodies 27 are arranged on the front end side of the rolling fulcrum frame 26 fixed to the lower surface side of the traveling machine body 1. A pair of left and right rear bearing bodies 28 are arranged on the rear end side of the pair of left and right rolling fulcrum frames 26. A pair of left and right front rolling fulcrum shafts 29 are passed through the left and right front bearing bodies 27, and a pair of left and right rear rolling fulcrum shafts 30 are passed through the left and right rear bearing bodies 28, respectively. A drive sprocket 22 (mission case 88) is arranged on the lower surface side of the traveling machine body 1 via the traveling chassis 1a. The rear side of the mission case 88 is fastened to the front portion of the traveling machine body 1.

  The base end sides of the pair of left and right upper front rolling arms 31 extended in the vertical direction are integrally fixed to one end side of the pair of left and right front rolling fulcrum shafts 29 extended in the left and right direction. To the other end side of the pair of left and right front rolling fulcrum shafts 29, the base end sides of the pair of left and right lower front rolling arms 33 extending in the front-rear direction are fixed integrally. That is, the pair of left and right upper front rolling arms 31 and the pair of left and right lower front rolling arms 33 rotate integrally around the pair of left and right front rolling fulcrum shafts 29, respectively. In addition, the front portion of the track frame 21 is connected to the distal end side of the lower front rolling arm 33 via a connecting shaft body 40.

  Moreover, the base end side of a pair of left and right upper rear rolling arms 32 is rotatably fitted to one end side of the rear rolling fulcrum shaft 30 extended in the left-right direction. As shown in FIG. 6, a pair of left and right front / rear connecting rolling frames 36 with turnbuckles that can be expanded and contracted are provided. The long rod-like front / rear connecting rolling frame 36 extends in the front / rear direction parallel to the traveling machine body 1 at a position lower than the upper surface of the traveling machine body 1. The front end side of the front / rear connecting rolling frame 36 is connected to the front end side of the pair of left and right upper front rolling arms 31 via the shaft body 35. The rear end side of the front / rear connecting rolling frame 36 is connected to the upper end side of the upper rear rolling arm 32 via a shaft body 37.

  As shown in FIGS. 4 to 8, a pair of left and right vehicle height adjusting hydraulic cylinders 38 for changing the inclination angle of the traveling body 1 in the left and right direction are provided. The traveling machine body 1 is provided with a pair of left and right cylinder support brackets 39. A pair of left and right vehicle height adjusting hydraulic cylinders 38 are connected to a pair of left and right cylinder support brackets 39 via a base shaft body 48, respectively. Piston rods 41 of a pair of left and right vehicle height adjusting hydraulic cylinders 38 are connected to the upper ends of the pair of left and right upper rear rolling arms 32 via front end side shaft bodies 42, respectively.

  To the other end side of the pair of left and right rear rolling fulcrum shafts 30, the base end sides of the pair of left and right lower rear rolling arms 34 are integrally fixed. That is, the pair of left and right rear rolling fulcrum shafts 30 and the pair of left and right lower rear rolling fulcrum arms 34 are configured to rotate integrally around the axis of the pair of left and right rear rolling fulcrum shafts 30, respectively. Further, one end side of the driven link body 175 is connected to the distal end side of the lower rear rolling arm 34 via the connecting shaft body 174. The rear portion of the track frame 21 is connected to the other end side of the driven link body 175 via a connecting shaft body 179.

  As shown in FIGS. 4 to 8, a front and rear tilt hydraulic cylinder 177 that changes the tilt angle of the traveling machine body 1 in the front and rear direction is provided. The base end sides of the pair of left and right pitching arms 176 are fixed to one end side of the pair of left and right rear rolling fulcrum shafts 30. The pair of left and right pitching arms 176 and the pair of left and right lower rear rolling arms 34 are configured to rotate integrally around the axis of the pair of left and right rear rolling fulcrum shafts 30, respectively. Further, a pair of left and right front and rear tilt hydraulic cylinders 177 are connected to the pair of left and right upper rear rolling arms 32 via a connecting shaft body 180, respectively. The front end side of the pitching arm 176 is connected to the piston rod 178 of the hydraulic cylinder 177 for forward / backward tilting via a connecting shaft body 181.

  As shown in FIGS. 4 and 5, the pair of left and right vehicle height adjusting hydraulic cylinders 38 and the front / rear inclination hydraulic cylinders 177 are arranged in a line in the front-rear direction in a side view or a plan view. A pair of left and right front rolling link mechanisms R1 that change the tilt angle in the left-right direction of the traveling machine body 1 by operating the pair of left and right vehicle height adjusting hydraulic cylinders 38 includes an upper front rolling arm (left and right tilt arm) 31, an upper rear rolling. It has an arm (left-right tilt arm) 32, a lower front rolling arm (front arm) 33, a lower rear rolling arm (rear arm) 34, a front / rear connecting rolling frame 36, and a driven link body (pitching link) 175. When the vehicle height adjusting hydraulic cylinder 38 is operated, the upper front rolling arm 31 and the lower front rolling arm 33 are integrally rotated around the front rolling fulcrum shaft 29, and at the same time, the upper rear rolling arm 32, The lower rear rolling arm 34, the pitching arm 176, and the forward / backward tilting hydraulic cylinder 177 rotate integrally around the rear rolling fulcrum shaft 30.

  That is, as shown in FIG. 7, when the vehicle height adjusting hydraulic cylinder 38 is operated, the relative distance between the traveling machine body 1 and the track frame 21 is maintained while maintaining the inclination angle of the traveling machine body 1 with respect to the track frame 21. Change. When the amount of subsidence of the left and right traveling crawlers 2 changes and the traveling machine body 1 tilts to the left and right, or when the operator wants to tilt the traveling machine body 1 to the left and right, the vehicle travels by automatic control or manual control of the vehicle height adjusting hydraulic cylinder 38. The horizontal inclination angle of the aircraft 1 can be changed, and the ground inclination angle of the traveling aircraft 1 in the horizontal direction can be maintained at a set angle (substantially horizontal posture).

  A pair of left and right rear pitching link mechanisms P1 that change the tilt angle in the front-rear direction of the traveling machine body 1 by the operation of the pair of left and right hydraulic cylinders 177 are a lower rear rolling arm (rear arm) 34, a driven link. It has a body (pitching link) 175 and a pitching arm (front and rear tilt arm) 176. When the forward / backward tilting hydraulic cylinder 177 is operated, the lower rear rolling arm 34 and the pitching arm 176 rotate integrally around the rear rolling fulcrum shaft 30, and the front rolling fulcrum shaft is driven via the driven link body 175. The track frame 21 is rotated around 29.

  That is, as shown in FIG. 8, when the forward / backward tilt hydraulic cylinder 177 is operated, the front / rear direction inclination angle of the traveling body 1 with respect to the track frame 21 is maintained while maintaining the lateral inclination angle of the traveling body 1 in the left / right direction. Change. When the traveling road surface on which the left and right traveling crawlers 2 are moved is an upward or downward sloping slope, or when the traveling machine body 1 tilts back and forth due to a change in the amount of settlement at the front (or rear) of the left and right traveling crawlers 2 Alternatively, when the operator wants to tilt the traveling machine body 1 back and forth, the front and rear tilt angle of the traveling machine body 1 is changed by automatic control or manual control of the front and rear tilt hydraulic cylinder 177, and the ground tilt angle of the traveling machine body 1 in the front and rear direction is reduced. Can be maintained at a set angle (substantially horizontal posture).

  The intermediate roller 25 that holds the non-grounded side of the traveling crawler 2 is rotatably supported on a roller shaft 25a that protrudes laterally from the traveling machine body 1. That is, on the non-grounded side of the traveling crawler 2 between the drive sprocket 22 and the intermediate roller 25, the inclination angle of the traveling body 1 in the left-right direction or the front-rear direction is changed by the vehicle height adjusting hydraulic cylinder 38 or the front-rear tilting hydraulic cylinder 177. However, the distance from the lower surface of the traveling machine body 1 is always maintained substantially constant.

  With the above configuration, as shown in FIG. 7, either one or both of the pair of left and right vehicle height adjusting hydraulic cylinders 38 are operated, and either one or both piston rods 41 of the pair of left and right vehicle height adjusting hydraulic cylinders 38 are operated. , One or both of the pair of left and right track frames 21 move downward, push down either one or both of the pair of left and right traveling crawlers 2 and push down the left or right side or both of the traveling body 1. It is configured to increase the vehicle height.

  Further, as shown in FIG. 4, one or both of the pair of left and right vehicle height adjusting hydraulic cylinders 38 are operated to retract the piston rod 41 of either one or both of the pair of left and right vehicle height adjusting hydraulic cylinders 38. In this case, either one or both of the pair of left and right track frames 21 move upward, pushes up one or both of the pair of left and right traveling crawlers 2 and raises the vehicle height on the left or right side or both of the traveling body 1. Is configured to be low. That is, by operating the pair of left and right vehicle height adjusting hydraulic cylinders 38 to change the heights of the contact surfaces of the left and right traveling crawlers 2 with respect to the traveling machine body 1, the inclination angle of the traveling machine body 1 in the horizontal direction can be increased. The traveling machine body 1 is adjusted so as to be supported substantially horizontally (left and right inclination angle 0 degree).

  As shown in FIG. 8, in the state where the piston rod 41 is advanced (or the piston rod 41 is retracted) where the vehicle height is high, the front / rear tilt hydraulic cylinder 177 is operated, and a pair of left / right front / rear tilt hydraulic cylinders 177 is operated. When the piston rods 178 are retracted, the pair of left and right pitching arms 176 are actuated, respectively, and the pair of left and right driven link bodies 175 are respectively pushed downward, so that the rear ends of both the pair of left and right track frames 21 Each side moves down simultaneously.

  As a result, the parallel posture of the lower rear rolling arm 34 with respect to the lower front rolling arm 33 is changed, the grounding side of the rear part of the pair of left and right traveling crawlers 2 is pushed down, and the vehicle on the rear end side of the traveling machine body 1 is pushed. The height is increased, and the traveling machine body 1 is configured to tilt forward and downward. That is, the rear end side of the traveling machine body 1 is moved up around the front rolling fulcrum shaft 29 so that the rear end side of the traveling machine body 1 is tilted to a forward inclined posture (front downward inclined posture) that is higher than the front end side. It is composed. As a result, when moving on a traveling road surface that is inclined forwardly upward, the longitudinal inclination of the traveling machine body 1 can be maintained substantially horizontal.

  In addition, by retracting the piston rods 178 of the pair of left and right hydraulic cylinders 177, the rear end sides of the pair of left and right track frames 21 are moved upward at the same time. Needless to say, the vehicle height on the rear end side becomes lower, and the traveling machine body 1 tilts backward.

  As is clear from the above description and FIGS. 4 to 8, the vehicle height adjustment as a traveling actuator 1 having a traveling crawler 2 as a left and right traveling unit and a rolling actuator that corrects the horizontal inclination of the traveling aircraft 1. In a work vehicle provided with a hydraulic cylinder 38 and a hydraulic cylinder 177 for longitudinal tilting as a pitching actuator for correcting the tilting posture of the traveling machine body in the longitudinal direction, the vehicle height adjusting hydraulic cylinder 38 and the hydraulic cylinder for longitudinal tilting 177 are Since it is arranged in a line in a plan view and a plan view, the installation length (connection support length) of the front / rear tilt hydraulic cylinder 177 can be shortened compared to the conventional case, and the direction other than the expansion / contraction direction acting on the front / rear tilt hydraulic cylinder 177 can be reduced. The twisting force can be reduced and the durability can be improved. Moreover, the lower surface side space of the traveling machine body 1 between the left and right traveling crawlers 2 can be widely formed, mud can be reduced from being accumulated on the lower surface side of the traveling machine body 1, and wet field workability can be improved. Further, it is possible to prevent the upper surface side structure of the traveling machine body 1 or the support position of the front and rear tilt hydraulic cylinder 177 from being restricted to each other, and the traveling machine body 1 and the like can be configured easily.

  As is apparent from the above description and FIGS. 4 to 8, the parallel link-like lower front rolling arm 33 (front arm) and lower rear rolling arm 34 (rear arm) actuated by the vehicle height adjusting hydraulic cylinder 38. ), And the pitching arm 176 is connected to either the lower front rolling arm 33 or the lower rear rolling arm 34, so that the vehicle height of the vehicle body 1 in the left-right inclined posture is maintained. The traveling machine body 1 can be tilted back and forth. The control performance of the vehicle height adjusting hydraulic cylinder 38 that corrects the tilting posture of the traveling machine body 1 in the left-right direction can be maintained, and the control performance of the front-rear tilting hydraulic cylinder 177 that corrects the tilting attitude of the traveling machine body 1 in the front-rear direction can be improved. .

  As apparent from the above description and FIGS. 4 to 8, the traveling machine body 1 having the left and right traveling crawlers 2 (traveling portions), the vehicle height adjusting hydraulic cylinder 38 (rolling actuator), and the forward / backward tilting hydraulic cylinder 177 ( A traveling actuator 1 is mounted on the left and right track frames 21 via the left and right link mechanisms R1 and P1 so that the traveling aircraft 1 can be lifted and lowered. In the work vehicle configured to be able to correct the inclination posture, the link mechanisms R1 and P1 have a parallel link-like lower front rolling arm 33 (front arm) and a lower rear rolling arm 34 (rear arm). The lower front rolling arm 33 or the lower side via the follower link body 175 (pitching link) of the track frame 21 Either parts rolling arm 34 are connected.

  Therefore, while the traveling body 1 can be tilted left and right by the operation of the parallel link-shaped lower front rolling arm 33 and lower rear rolling arm 34 (control of the vehicle height adjusting hydraulic cylinder 38), the lower front portion The front or rear side of the track frame 21 is moved up and down via either the rolling arm 33 or the lower rear rolling arm 34 and the driven link body 175 (control of the front / rear tilt hydraulic cylinder 177) to move the traveling machine body 1 back and forth. Can tilt. The traveling machine body 1 can be tilted back and forth in a state where the vehicle height of the traveling machine body 1 in the left-right tilted posture is maintained (control of the vehicle height adjusting hydraulic cylinder 38 is stopped). The connecting structure of the traveling machine body 1 and the track frame 21 can be easily configured, or the control of the hydraulic cylinder 177 for front and rear tilt can be easily executed. A pitching structure for changing the tilting posture of the traveling machine body 1 in the front-rear direction can be assembled at low cost, or a pitching control function for changing the tilting posture of the traveling machine body 1 in the front-rear direction can be improved.

  As apparent from the above description and FIGS. 4 to 8, both the lower front rolling arm 33 and the lower rear rolling arm 34 are connected to the vehicle height adjusting hydraulic cylinder 38 and are connected to the driven link body 175. A front / rear tilt hydraulic cylinder 177 is connected to either the side rear rolling arm 34 or the lower front rolling arm 33. Therefore, the front / rear tilt hydraulic cylinder 177 can be assembled compactly close to the vehicle height adjusting hydraulic cylinder 38. Further, it is possible to improve the pitching function for changing the tilting posture in the front-rear direction of the traveling machine body 1 while preventing the rolling function for changing the tilting posture in the left-right direction of the traveling machine body 1 from being complicated.

  As is clear from the above description and FIGS. 4 to 8, the transmission case 88 is arranged in the front portion of the traveling machine body 1, and the front and rear tilting hydraulic cylinder 177 is connected to the lower rear rolling arm 34. The lower rear rolling arm 34 is connected to the track frame 21 via a driven link body 175. Therefore, by installing the front part of the track frame 21 close to the support part of the mission case 88 and changing the inclined posture of the traveling machine body 1 in the front-rear direction, the lower surface side of the traveling machine body 1 and the traveling crawler 2 It is possible to prevent the upper surface side from interfering. The front / rear tilt hydraulic cylinder 177 can be assembled in a compact manner in a line at substantially the same height from the middle to the rear of the track frame 21 in the vicinity of the vehicle height adjusting hydraulic cylinder 38. For example, it is possible to easily secure a tilt change range in the front-rear direction of the traveling machine body 1 or simplify the connection structure between the traveling machine body 1 and the track frame 21.

  As apparent from the above description and FIGS. 4 to 8, the upper rear rolling arm 32 connected to the vehicle height adjusting hydraulic cylinder 38 and the pitching arm 176 connected to the front / rear tilting hydraulic cylinder 177 are connected to the same fulcrum shaft 30. A front / rear tilt hydraulic cylinder 177 is provided on the upper rear rolling arm 32 connected to the vehicle height adjusting hydraulic cylinder 38 while being disposed on the (rear rolling fulcrum shaft), and the vehicle height adjusting hydraulic cylinder 38 and the front / rear tilt hydraulic cylinder 177 are provided. It is arranged in a row toward the front and back. Therefore, the traveling machine body 1 having the same specification can be easily shared between the specification with the front / rear tilt hydraulic cylinder 177 and the specification without it. In addition, a space between the left and right traveling crawlers 2 is formed wide on the lower surface side of the traveling machine body 1 so that the traveling crawler 2 is easily sunk, and workability such as wet fields is easily swollen or mud such as the rice field is greatly raised. It can improve the running performance of easy field headlands.

  As shown in FIG. 4, the front lowest stopper 185 is fixed to the traveling chassis 1a. One end side of the front lowering stopper 185 is extended to the upper surface side of the lower front rolling arm 33. When the front vehicle height of the traveling machine body 1 is the lowest (the state shown in FIG. 4 or FIG. 6), that is, when the front side of the traveling machine body 1 and the track frame 21 are closest to each other, the upper side of the lower front rolling arm 33 is The lower surface of the lowest stop stopper 185 comes into contact with the front side of the traveling machine body 1 and is supported at the lowest position. By contacting the lower front rolling arm 33 and the front lowering stopper 185, the front upper surface of the traveling crawler 2 is prevented from interfering with the front lower surface of the traveling machine body 1.

  In addition, a rear lowermost stopper 186 is fixed to the lower surface of the rear bearing body 28. A receiving body 187 is fixed to the track frame 21. When the rear vehicle height of the traveling machine body 1 is the lowest (the state shown in FIG. 4 or FIG. 6), that is, when the rear side of the traveling machine body 1 and the track frame 21 are closest to each other, The lower surface of the lowest-stop stopper 186 comes into contact, and the rear side of the traveling machine body 1 is supported at the lowest position. The contact between the receiving body 187 and the rear-most lowering stopper 186 prevents the rear upper surface of the traveling crawler 2 from interfering with the rear lower surface of the traveling machine body 1.

  FIG. 9 shows crawler attitude maps ML and MR as attitude data indicating the relationship between the ground height of the traveling machine body 1 and the front and rear inclination angle of the traveling machine body 1 (attitude range on the left and right traveling crawler 2 side). There are two types of crawler attitude maps ML and MR, one corresponding to the left traveling crawler 2 side and the one corresponding to the right traveling crawler 2 side, both of which have common contents. The crawler posture maps ML and MR are stored in advance in a work controller 371 described later. In FIG. 9, the height on the left and right traveling crawler 2 side in the traveling machine body 1 is taken on the vertical axis, and the longitudinal inclination angle of the traveling machine body is taken on the horizontal axis. The posture data is not limited to the map format as in the embodiment, and may be a function table, set data (data table), or the like. The left and right crawler posture maps ML and MR include normal ranges AR2 and AR4 which are normal posture ranges, and limited ranges AR1, AR3 and AR5 to AR7 which are front and rear inclination ranges on the vehicle height upper limit side or lower limit side. Is stipulated. The range surrounded by the thick solid line in FIG. 9 is a combination of the normal ranges AR2 and AR4.

  In the embodiment, the vehicle height adjusting hydraulic cylinder is basically based on the detection results of the left and right vehicle height sensors 375 and 376 and the front and rear inclination sensor 381 in the range (normal ranges AR2 and AR4) surrounded by the thick solid line in FIG. 38 is extended and contracted to maintain the vehicle height adjusting operation by the vehicle height adjusting hydraulic cylinder 38 within a predetermined range, and then the vehicle height adjusting hydraulic cylinder 38 or the tilting operation by the front / rear tilting hydraulic cylinder 177 is executed. ing.

  For example, the height C of the vehicle height adjustment hydraulic cylinder 38 (left-right tilting operation) is about 60% (about 2/3) of the maximum height E and the maximum height E. Between the height A of about 10% (about 1/10), each forward / backward tilt hydraulic cylinder in the range from 0 ° to the maximum forward tilt angle F (for example, about 5 °) is the forward / backward tilt angle of the traveling body 1. The forward leaning operation of 177 is executed, and the traveling machine body 1 is supported in the forward leaning posture (forward downward leaning posture). Between the height D and the height C of about 95% with respect to the maximum height E, within a range of about 80% (about 4/5) of the forward tilt angle F1 with respect to the maximum forward tilt angle F, The forward tilting operation of the forward / backward tilting hydraulic cylinder 177 is executed. When the height is A or less, the forward tilting operation of the front / rear tilt hydraulic cylinder 177 is executed within a range of the forward tilt angle F2 of about 60% (about 2/3) with respect to the maximum forward tilt angle F.

  If the height of each traveling crawler 2 side is equal to or higher than the height C, the forward tilting operation on each traveling crawler 2 side is less than the forward tilt angle F1 of about 80% (about 4/5) with respect to the maximum forward tilt angle F Therefore, it is possible to prevent the front end side of the reaping device 3 from being supported low. In this case, even when the cutting device 3 is raised to the non-working position (high position) by the lifting / lowering hydraulic cylinder 4, the traveling machine body 1 can properly tilt forward. For example, even when the traveling machine body 1 moves in a posture inclined forward and downward during operations such as entering and exiting a field and loading and unloading to a truck bed, the front end side of the reaping device 3 is prevented from colliding with the rice field or road surface. it can.

  On the other hand, the height D of the vehicle height adjusting hydraulic cylinders 38 (left-right tilting operation) is about 95% of the maximum height E and about 20% of the maximum height E. Between the forward and backward tilt angles of the traveling machine body 1 within a range from 0 ° to a maximum backward tilt angle R (for example, about 3 °), the backward tilting operation of each forward / backward tilt hydraulic cylinder 177 is executed. 1 is supported in a backward inclined posture (backward downward inclined posture). The backward tilting operation of the forward / backward tilt hydraulic cylinder 177 is executed within a range of about 25% (about ¼) of the rearward tilt angle R3 with respect to the maximum rearward tilt angle R.

  If the height of each traveling crawler 2 side is equal to or higher than the height B, the traveling machine body 1 can be tilted backward to the maximum rearward tilting angle R, so that the cutting device 3 is moved to the non-working position (high position) by the lifting hydraulic cylinder 4. Even if it is raised, the traveling machine body 1 can be smoothly moved backward and tilted, the reaping device 3 can be further raised, and the reaping device 3 can be quickly avoided with respect to obstacles.

  In the case of the low heights A and B that are about 20% (about 1/5) or less with respect to the maximum height E, the traveling machine body is higher than the height A at which the forward tilting operation of the traveling machine body 1 is restricted. The height B at which the backward tilting operation of 1 is restricted is set higher (height A <height B). The maximum backward inclination angle R (for example, about 3 °) and the forward inclination angle F2 of about 60% (about 2/3) with respect to the maximum forward inclination angle F are set to be approximately equal. That is, the maximum rearward tilt angle R is set in accordance with the magnitude of the tilt angle of about 60% with respect to the maximum forward tilt angle F.

  By setting the maximum forward tilt angle F larger than the maximum rearward tilt angle R as in the embodiment, the traveling crawler 2 sinks greatly in the super wet field, and the cutting height is increased by raising the vehicle height of the traveling machine body 1. The traveling machine body 1 is moved forward without lowering the vehicle height of the traveling machine body 1 without increasing the running resistance and without lowering the cutting device 3 and causing the cutting blade device 222 or the like to enter the soil. It can be tilted. Therefore, the stock of uncut cereal can be cut by the cutting blade device 222 at a predetermined height.

  In the embodiment, the posture change operation of the traveling machine body 1, that is, the vehicle by the vehicle height adjusting hydraulic cylinder 38 or the front / rear tilt hydraulic cylinder 177 is combined by the combination of the restriction ranges AR1, AR3, AR5 to AR7 of the both crawler posture maps ML, MR. High adjustment and tilting movements are limited. The table shown in FIG. 10 is an operation rule table T relating to combinations of the limited ranges AR1, AR3, AR5 to AR7. Similarly to the crawler attitude maps ML and MR, the operation rule table T is also stored in advance in a work controller 371 described later.

  The crosses in the operation rule table T in FIG. 10 indicate prohibited operation types. For example, when the posture range (ground height and inclination angle) on the left traveling crawler 2 side is the restriction range AR1, and the posture range on the right traveling crawler 2 side is the restriction range AR3, the left / right inclination control and the front / rear inclination are performed automatically or manually. During the execution of the control, even if the traveling machine body 1 is requested to tilt right or forward, the traveling body 1 is prohibited from tilting right and tilting forward. That is, even if there is a request for the right tilting operation of the traveling machine body 1, the extension movement of the left vehicle height adjustment hydraulic cylinder 38 and the shortening movement of the right vehicle height adjustment hydraulic cylinder 38 are prohibited. Further, even if the traveling machine body 1 is requested to tilt forward, the forward / backward tilting hydraulic cylinder 177 is prohibited from extending. As can be seen from the operation rule table T in FIG. 10, the posture change operation (the vehicle height adjustment hydraulic cylinder 38 and the front / rear inclination) of the traveling machine body 1 is achieved by the combination of the restriction ranges AR1, AR3, AR5 to AR7 of the crawler posture maps ML, MR. The vehicle height adjustment operation and the inclination operation by the hydraulic cylinder 177 are determined.

  Next, referring to FIGS. 11 to 13, the tilt switch mechanism 54 and the vehicle height switch mechanism 55 for operating the vehicle height adjusting hydraulic cylinder 38 and the front / rear tilt hydraulic cylinder 177 and the tilt switch mechanism 54 are operated. A posture operation lever 56 as a tilting operation tool and a vehicle height button 57 as a vehicle height operation tool for operating the vehicle height switch mechanism 55 will be described.

  As shown in FIG. 11 and FIG. 12, a posture operation lever 56 as a tilt operation tool is projected outwardly from one of the left and right side surfaces (right side surface in the embodiment) of the steering column 46. The posture operation lever 56 is located on the lower right side of the steering round handle 11 as the steering operation tool. The operator sitting on the driver's seat 12 holds the steering wheel handle 11 with the left hand, the operator holds the grip portion 56a of the posture operation lever 56 with the right hand, and the posture operation lever 56 can be tilted up and down and front and rear. Yes.

  As shown in FIGS. 11 and 12, a tilting switch mechanism 54 is provided at the base end portion of the posture operation lever 56. As will be described in detail later, the tilt switch mechanism 54 includes a left tilt switch 61, a right tilt switch 62, a forward tilt switch 63, and a rear tilt switch 64 (see FIG. 14). The tilting switch 61, the right tilting switch 62, the forward tilting switch 63, or the rearward tilting switch 64 are selectively turned on by tilting the posture operation lever 56 in the up / down / front / rear direction. That is, by manually operating the attitude control lever 56, the traveling machine body 1 is tilted to the left, right, front, or rear side, and the inclined attitude of the traveling machine body 1 is changed.

  For example, when the posture operation lever 56 is tilted upward, the left tilt switch 61 (left tilt solenoid valve 261 or right tilt solenoid valve 262) is turned on, and the traveling machine body 1 tilts to the left. When the posture operation lever 56 is tilted downward, the right tilt switch 62 (left tilt solenoid valve 261 or right tilt solenoid valve 262) is turned on, and the traveling machine body 1 tilts to the right. If the posture operation lever 56 is tilted forward, the forward tilt switch 63 (front / rear tilt electromagnetic valves 266 and 267) is turned on, and the traveling machine body 1 tilts forward. When the attitude control lever 56 is tilted backward, the rear tilt switch 64 (front / rear tilt electromagnetic valves 266 and 267) is turned on, and the traveling machine body 1 tilts rearward.

  As shown in FIG.11 and FIG.13, the substantially circular wheel part 51 in the steering round handle 11 has a vehicle height button as a vehicle height operation tool on the upper surface of the grip part on the left or right side (left side in the embodiment). 57 is provided. The vehicle height button 57 is for operating the vehicle height switch mechanism 55 that operates the vehicle height adjusting hydraulic cylinder 38, and is configured to be operated to be pushed in two directions. Although details will be described later, the vehicle height switch mechanism 55 includes a vehicle height increase switch 65 and a vehicle height decrease switch 66 (see FIG. 14). By pushing the vehicle height button 57 in the front-rear direction, the vehicle height raising switch 65 or the vehicle height lowering switch 66 is selectively turned on, and the vehicle height of the traveling machine body 1 is changed.

  That is, while the vehicle height button 57 is pushed forward, the vehicle height lowering switch 66 is turned on, and the left tilting electromagnetic valve 261 and the right tilting electromagnetic valve 262 are turned on so as to lower the traveling machine body 1. The ground height of the traveling machine body 1 is lowered. On the contrary, while the vehicle height button 57 is pushed backward, the vehicle height raising switch 65 is turned on, and the left tilt solenoid valve 261 and the right tilt solenoid valve 262 are turned on so as to raise the traveling machine body 1. As a result, the ground height of the traveling machine body 1 is increased. When the operator releases his / her finger from the vehicle height button 57, the vehicle height button 57 returns to the initial position by a biasing force of a spring (not shown), and the traveling machine body 1 is maintained at the ground height at this time.

  Only during the manual operation of the vehicle height button 57, the vehicle height adjusting hydraulic cylinder 38 is operated, and the traveling machine body 1 can be supported at an appropriate ground height. For example, even when the traveling machine body 1 is moved in an inclined position when the truck carrying the machine (combine) is loaded onto or unloaded from the loading platform, or when the machine is moved in or out of the field, the machine is damaged due to contact with the road surface. Can be reduced.

  As shown in FIGS. 11 and 13, in the embodiment, the vehicle height button 57 is positioned on the left side and the posture operation lever 56 is positioned on the right side as viewed from the operator seated on the driver seat 12. That is, the vehicle height button 57 and the posture operation lever 56 are positioned on the opposite sides as viewed from the operator seated on the driver seat 12. The positional relationship between the vehicle height button 57 and the posture operation lever 56 may be reversed to the left and right in the embodiment. With this configuration, the vehicle height button 57 can be operated with one hand (left hand), and the posture operation lever 56 can be operated with the other hand (right hand). That is, since the vehicle height button 57 and the posture operation lever 56 can be operated using both hands (sorting), the operability when the posture of the traveling machine body 1 is manually changed is good.

  In the embodiment, in order to deal with, for example, the case where the vehicle height button 57 and the posture operation lever 56 are operated simultaneously, the vehicle height adjustment operation of the vehicle height adjustment hydraulic cylinder 38 by the vehicle height button 57 (the elevation movement of the traveling machine body 1) is performed. The vehicle body height adjusting hydraulic cylinder 38 or the forward / backward tilting hydraulic cylinder 177 is configured to have priority over the tilting operation (the tilting motion of the traveling machine body 1) by the posture operation lever 56. Therefore, the vehicle height adjusting operation of the vehicle height adjusting hydraulic cylinder 38 is executed first to maintain the vehicle height of the traveling machine body 1 at a predetermined vehicle height, and then the vehicle height adjusting hydraulic cylinder 38 or the front / rear tilting hydraulic cylinder 177 is maintained. Thus, for example, it is possible to prevent the front portion of the reaping device 3 (the front portion of the combine) from entering the soil such as a farm field or a straw. Further, since the supply and discharge of the hydraulic oil to the vehicle height adjusting hydraulic cylinder 38 and the supply and discharge of the hydraulic oil to the front and rear tilt hydraulic cylinder 177 are executed separately, the four hydraulic cylinders 38, As a result, the responsiveness of 177 can be ensured, and the posture control function in the combine can be improved. There is little possibility that the operating speeds of the hydraulic cylinders 38 and 177 are influenced by each other. In addition, the work pump 91b can be configured at low cost without increasing the size.

  In the embodiment, the traveling machine body 1 is tilted to the left by the upward operation of the posture operation lever 56, and the traveling machine body 1 is tilted to the right by the downward operation, while the traveling machine body 1 is tilted forward and backward by the forward operation of the posture operation lever 56. Therefore, the relationship between the operation direction of the posture operation lever 56 and the tilting direction of the traveling machine body 1 is the same as viewed from the operator. For this reason, the inclination attitude | position of the traveling body 1 can be changed smoothly without a sense of incongruity by manual operation of the attitude | position operation lever 56. FIG.

  Next, with reference to FIG. 14, the left / right tilt control, the front / back tilt control of the combine (running vehicle body 1), and the lifting / lowering control of the reaping device 3 will be described. It should be noted that the control of the vehicle height adjustment of the combine (traveling machine body 1) is included in the left / right tilt control. The traveling machine 1 of the combine is equipped with a work controller 371 that controls the above-described various controls. Although not shown in detail, the work controller 371 includes a CPU that executes various arithmetic processes and controls, a ROM that stores a control program, and a RAM that stores various data.

  As shown in FIG. 14, the work controller 371 includes a crop sensor 372 that detects the harvested cereal crops harvested by the harvesting device 3, a work switch 373 that detects the operation of the harvesting device 3, and the horizontal direction of the traveling machine body 1. A pendulum-type left / right tilt sensor 374 that detects an inclination angle, a potentiometer-type left vehicle height sensor 375 that detects a distance (vehicle height) between the traveling vehicle body 1 and the left track frame 21, and a traveling vehicle body 1 and a right track A potentiometer-type right vehicle height sensor 376 that detects the distance (vehicle height) from the frame 21 and a manual dial-switching potentiometer-type left / right tilt setting device 377 that initially sets the reference value of the lateral tilt angle of the traveling machine body 1 Is connected.

  The work controller 371 is connected to a left tilting solenoid valve 261 and a right tilting solenoid valve 262. With this configuration, the left tilt solenoid valve 261 or the right tilt solenoid valve 262 is switched based on the detected value of the left / right tilt sensor 374, the detected value of the left vehicle height sensor 375, and the detected value of the right vehicle height sensor 376, and the left vehicle The high adjustment hydraulic cylinder 38 or the right vehicle height adjustment hydraulic cylinder 38 is operated to correct the inclination of the traveling machine body 1 in the left-right direction, and is automatically controlled so that the traveling machine body 1 becomes substantially horizontal in the left-right direction.

  Further, the work controller 371 includes a pendulum type front / rear tilt sensor 381 that detects the front / rear direction tilt angle of the traveling machine body 1 and the front / rear tilt angles of the left and right sides of the traveling machine body 1 Potentiometer-type left and right pitching sensors 382a, 382b for detecting a tilt angle), a manual dial-switching potentiometer-type front / rear tilt setter 383 for initially setting a reference value of the tilt angle of the traveling body 1 in the front-rear direction, and a forward / backward tilt A solenoid valve 266 is connected. With this configuration, the front / rear tilting solenoid valve 266 is switched based on the detected value of the front / rear tilt sensor 381, the detected values of the pitching sensors 382a and 382b, and the set value of the front / rear tilt setter 383, and the front / rear tilt hydraulic cylinder 177 is switched. , And the inclination of the traveling machine body 1 in the front-rear direction is corrected, so that the traveling machine body 1 is automatically controlled so as to be substantially horizontal in the front-rear direction.

  A left tilt switch 61, a right tilt switch 62, a forward tilt switch 63, a rear tilt switch 64, a vehicle height increase switch 65, and a vehicle height decrease switch 66 are connected to the input side of the work controller 371. With this configuration, the vehicle height adjusting hydraulic cylinder 38 or the front / rear tilt hydraulic cylinder 177 is actuated by a manual operation such as a tilt operation in the up / down / front / rear direction of the posture operation lever 56 or a push operation in the front / rear direction of the vehicle height button 57. Manual control can be performed so that the traveling machine body 1 is supported in an inclined posture desired by the operator.

  On the other hand, as shown in FIG. 14, the work controller 371 includes a vehicle speed sensor 385 that detects the rotational speed (vehicle speed) of the traveling crawler 2, and a potentiometer-type cutting height sensor 386 that detects the ground height of the cutting device 3. A manual dial switching potentiometer-type cutting height setting device 387 for initially setting a reference value for the ground height of the cutting device 3 is connected to a cutting lift electromagnetic valve 260. With this configuration, the cutting lift solenoid valve 260 is switched based on the detection value of the vehicle speed sensor 385, the detection value of the cutting height sensor 386, and the setting value of the cutting height setting device 387, and the cutting lift hydraulic cylinder 4 Is operated, the ground height of the reaping device 3 is corrected, and the grain reaper cutting height of the reaping device 3 is automatically controlled so as to be substantially constant.

  Further, on the input side of the work controller 371, a back switch 391 as a straight traveling detection means for detecting the forward / backward traveling state of the traveling machine body 1 (whether the traveling direction of the traveling machine body 1 is the forward side or the reverse side), A turning angle sensor 392 as a turning detection means for detecting a turning state (turning direction and turning angle) is electrically connected. The back switch 391 of the embodiment is configured to be turned on by a reverse operation (backward tilting operation) of the main transmission lever 43 and turned off by a forward operation (forward tilting operation). The cutting angle sensor 392 of the embodiment detects the turning state of the traveling machine body 1 from the turning operation angle of the steering round handle 11, and a rotary encoder or a rotary potentiometer, for example, is employed. The straight traveling detection means is not limited to the configuration associated with the main transmission lever 43, and may be configured to detect the forward / rearward traveling state of the traveling machine body 1 in association with the power transmission system of the mission case 88. The turning detection means is not limited to the configuration associated with the steering wheel handle 11 but may be configured to detect the turning state of the traveling machine body 1 in association with the power transmission system of the mission case 88.

  As shown in FIG. 14 and FIG. 16, in the embodiment, the traveling machine body 1 is shifted to the ground horizontal posture by manual operation of the posture operation lever 56 or automatic control of the vehicle height adjusting hydraulic cylinder 38 and the forward / backward tilting hydraulic cylinder 177. In such a case, the changing operation of the left and right tilt posture of the traveling machine body 1 or the changing operation of the front and back tilt posture of the traveling machine body 1 is temporarily stopped, and the stopped state is notified to the operator by, for example, the buzzer 390 ringing. Yes. Accordingly, it is possible to control the expansion / contraction operation of the vehicle height adjusting hydraulic cylinder 38 or the front / rear tilt hydraulic cylinder 177 without greatly deviating from the tilt posture of the traveling machine body 1 from the tilt posture desired by the operator (predicted tilt posture). become. The manual operation of the posture operation lever 56 can prevent the traveling machine body 1 from being excessively tilted in the front-rear and left-right directions. The manual control function of the vehicle height adjusting hydraulic cylinder 38 and the forward / backward tilt hydraulic cylinder 177, these automatic control functions, or the manual operability of the attitude control lever 56 can be easily improved.

  Next, with reference to FIG. 7 to FIG. 10 and FIG. 14 to FIG. 17, the culm cutting height control mode of the reaping device 3 and the combine tilt control mode (posture control mode) will be described. As shown in the flowchart of FIG. 15, when the engine 14 is started, the crop sensor 372 value, the left / right tilt sensor 374 value, the left vehicle height sensor 375 value, the right vehicle height sensor 376 value, the left / right tilt setter 377 value, the front / rear tilt The sensor 381 value, the left and right pitching sensors 382a and 382b values, the front / rear inclination setting device 383 value, the vehicle speed sensor 385 value, the cutting height sensor 386 value, and the cutting height setting device 387 value are read. During the cutting operation with the work switch 373 turned on, cutting height control is executed. Further, regardless of whether the work switch 373 is on or off, the left / right tilt control and the front / rear tilt control shown in the flowchart of FIG. 16 are executed.

  As shown in the flowchart of FIG. 15, if the crop sensor 372 is turned on during the cutting operation with the work switch 373 turned on, the vehicle speed sensor 385 value, the cutting height sensor 386 value, and the cutting height setter 387. When it is determined that the harvesting height of the harvesting device 3 is low based on the value, the harvesting lifting / lowering solenoid valve 260 is switched, and the harvesting lifting hydraulic cylinder 4 is operated to control the lifting of the harvesting device 3 so that the harvesting is performed. The ground height of the device 3 is corrected. On the other hand, when it is determined that the harvesting height of the harvesting device 3 is high, the lifting / lowering electromagnetic valve 260 is switched to operate the lifting hydraulic cylinder 4 to control the lowering of the harvesting device 3 so that the harvesting device 3 Correct the height of the ground. By the cutting height control of FIG. 13, the culm cutting height of the cutting device 3 set by the cutting height setting unit 387 can be automatically maintained.

  The flowchart of FIG. 16 shows a specific control mode of left / right tilt control and front / back tilt control. In the left / right and front / rear tilt control, when the posture operation lever 56 or the vehicle height button 57 is not manually operated, the left / right tilt sensor 374 value, the left vehicle height sensor 375 value, the right vehicle height sensor 376 value, Based on the inclination setter 377 value, the front and rear inclination sensor 381 value, the pitching sensors 382a and 382b values, the front and rear inclination setter 383 values, and the crawler attitude maps ML and MR, the attitude ranges AR1 on the traveling crawler 2 side. AR7 is calculated. If it is determined that the traveling machine body 1 is tilted to the left, the left tilting solenoid valve 261 or the right tilting solenoid valve 262 is switched to operate the left vehicle height adjustment hydraulic cylinder 38 or the right vehicle height adjustment hydraulic cylinder 38, and the traveling machine body 1 is raised or the right side of the traveling machine body 1 is lowered (the posture of the traveling machine body 1 is changed to the right tilt direction).

  On the other hand, if it is determined that the traveling machine body 1 is tilted to the right, the left tilt solenoid valve 261 or the right tilt solenoid valve 262 is switched to operate the left vehicle height adjustment hydraulic cylinder 38 or the right vehicle height adjustment hydraulic cylinder 38, The right side of the traveling machine body 1 is raised or the left side of the traveling machine body 1 is lowered (the posture of the traveling machine body 1 is changed to the left tilt direction).

  Therefore, the left-right inclination angle of the traveling machine body 1 is automatically corrected by the left-right inclination control of the combine (traveling machine body 1) shown in FIG. Based on the value of the left / right tilt setting device 377, the traveling posture of the traveling machine body 1 in the left / right direction can be maintained. When the operator operates the left / right tilt setting device 377, the traveling machine body 1 is supported in the left / right tilt angle posture (ground horizontal posture) set by the left / right tilt setting device 377.

  Further, as shown in the flowchart of FIG. 16, if it is determined from the posture ranges AR1 to AR7 on the side of each traveling crawler 2 that the traveling vehicle body 1 is in a forward leaning posture that is inclined downward to the front side, based on the operation rule table T. Then, it is determined whether or not the posture change in the backward tilt direction of the traveling machine body 1 is permitted. When permitting the posture change, the front / rear tilting solenoid valve 266 is switched to operate the left / right front / rear tilt hydraulic cylinders 177 to lower the rear side of the traveling machine body 1 tilted forward. That is, the forward inclination angle of the traveling machine body 1 is automatically corrected by the forward / backward inclination control of the combine (traveling machine body 1) shown in FIG. The front-rear inclination angle (horizontal posture) of the traveling machine body 1 matches the front-rear inclination setter 383 value.

  In this case, when the traveling machine body 1 is in the horizontal posture with respect to the traveling portion (parallel posture) with respect to the track frame 21 before reaching the target inclined posture, the backward tilting operation is temporarily stopped for a certain time, The buzzer 390 connected to the work controller 371 is sounded to notify the operator. Then, when a certain time has elapsed from the temporary stop, the backward tilting operation is automatically resumed. With the temporary stop and continuous buzzer 390, the operator can easily recognize the horizontal orientation of the traveling unit 1 with respect to the traveling unit without visually recognizing the display unit.

  On the other hand, when the posture change in the backward tilt direction is prohibited, the left vehicle height adjustment hydraulic cylinder 38 or the right vehicle height adjustment hydraulic cylinder 38 is operated while the buzzer 390 is intermittently sounded to notify the operator. After the right or left side of the traveling machine body 1 is moved up and down to change the posture range on each traveling crawler 2 side into the normal ranges AR2 and AR4, the backward tilting operation is subsequently performed. That is, the forward tilt correction control for automatically correcting the forward tilt angle of the traveling machine body 1 is executed, and the forward / backward tilt angle (horizontal orientation with respect to the ground) of the traveling machine body 1 coincides with the front / back tilt setter 383 value.

  Furthermore, as shown in the flowchart of FIG. 16, if it is determined from the posture ranges AR1 to AR7 on the side of each traveling crawler 2 that the traveling vehicle body 1 is tilted backward and tilted rearward, the operation rule table T is displayed. Based on this, it is determined whether or not the posture change of the traveling machine body 1 in the forward tilt direction is permitted. When permitting the posture change, the front / rear tilting electromagnetic valve 266 is switched to operate the left / right front / rear tilt hydraulic cylinders 177 to raise the rear side of the traveling machine body 1 inclined rearward. That is, the backward inclination angle of the traveling machine body 1 is automatically corrected by the forward / backward inclination control of the combine (traveling machine body 1) shown in FIG. The front-rear inclination angle (horizontal posture) of the traveling machine body 1 matches the front-rear inclination setter 383 value.

  In this case, when the traveling machine body 1 is in the horizontal posture with respect to the traveling portion (parallel posture) with respect to the track frame 21 before reaching the target inclined posture, the forward leaning operation is temporarily stopped for a certain period of time, The buzzer 390 connected to the work controller 371 is sounded to notify the operator. Then, the forward tilting operation is automatically restarted when a certain time has passed since the temporary stop. With the temporary stop and continuous buzzer 390, the operator can easily recognize the horizontal orientation of the traveling unit 1 with respect to the traveling unit without visually recognizing the display unit.

  On the other hand, when the posture change in the forward tilt direction is prohibited, the left vehicle height adjustment hydraulic cylinder 38 or the right vehicle height adjustment hydraulic cylinder 38 is operated while the buzzer 390 is intermittently sounded to notify the operator. The forward tilting operation is subsequently performed after the right or left side of the traveling machine body 1 is moved up and down to change the posture range on each traveling crawler 2 side into the normal ranges AR2 and AR4. That is, the backward inclination correction control that automatically corrects the rearward inclination angle of the traveling machine body 1 is executed, and the forward and backward inclination angle (horizontal posture) of the traveling machine body 1 coincides with the forward / backward inclination setting device 383 value.

  As shown in the flowcharts of FIGS. 16 and 17, when the posture operation lever 56 is manually operated, a tilting posture of the traveling machine body 1 in the left-right direction or in a front-back direction is determined by tilting the posture operation lever 56 in the vertical direction. The posture is changed. If the posture operation lever 56 is tilted upward (left tilt operation), based on the operation rule table T, it is determined whether or not the posture change of the traveling machine body 1 in the left tilt direction is permitted. When permitting the posture change, either the left or right vehicle height adjusting hydraulic cylinder 38 is operated, and the traveling machine body 1 is supported in a posture in which the left side is lower than the right side of the traveling machine body 1. Further, if the posture operation lever 56 is tilted downward (right tilt operation), based on the operation rule table T, it is determined whether or not the posture change of the traveling machine body 1 in the right tilt direction is permitted. When permitting the posture change, either one of the left and right vehicle height adjusting hydraulic cylinders 38 is operated, and the traveling machine body 1 is supported in a posture in which the right side is lower than the left side of the traveling machine body 1.

  When the posture operation lever 56 is tilted forward (forward tilt operation), based on the operation rule table T, it is determined whether or not to permit the posture change of the traveling aircraft body 1 in the forward tilt direction. The left and right front and rear tilt hydraulic cylinders 177 are operated in the same direction by substantially the same amount in the same direction, so that the traveling machine body 1 is supported in a posture in which the front side is lower than the rear side of the traveling machine body 1. Further, when the posture operation lever 56 is tilted backward (backward tilt operation), it is determined based on the operation rule table T whether or not the posture change in the backward tilt direction of the traveling machine body 1 is permitted. In this case, the left and right forward / backward tilt hydraulic cylinders 177 are operated in the same direction by substantially the same amount in the same direction so that the traveling machine body 1 is supported in a posture in which the rear side is lower than the front side of the traveling machine body 1. In any case where posture change is prohibited, for example, the buzzer 390 sounds to notify the operator of that fact.

  During the manual operation of the posture control lever 56, when the traveling machine body 1 is in the horizontal posture (parallel posture) with respect to the track frame 21, the posture changing operation described above is temporarily stopped for a certain period of time. The buzzer 390 connected to the controller 371 is sounded to notify the operator. If the manual operation of the posture operation lever 56 is continued after a lapse of a certain time from the temporary stop, the posture changing operation described above is automatically resumed. The operator can easily recognize the horizontal posture of the traveling machine body 1 with respect to the traveling unit 1 by the temporary stop and the ringing of the buzzer 390.

  Further, as shown in FIGS. 16 and 17, when the operator manually operates the vehicle height button 57, the vehicle height of the traveling machine body 1 is changed by pushing the vehicle height button 57 in the front-rear direction. That is, when the vehicle height button 57 is pushed forward, based on the output of the vehicle height lowering switch 66, the left and right vehicle height adjustment hydraulic cylinders 38 are operated in the same direction by the same amount in the same direction to lower the traveling machine body 1. The ground height of the traveling machine body 1 is lowered. Conversely, when the vehicle height button 57 is pushed backward, the left and right vehicle height adjusting hydraulic cylinders 38 are actuated at the same time in the same direction in the same direction based on the output of the vehicle height raising switch 65 to raise the traveling machine body 1. The ground height of the traveling machine body 1 is increased. As a result, the vehicle height of the combine is changed to the height desired by the operator while maintaining the front, rear, left and right tilt postures of the traveling machine body 1 as they are.

  On the other hand, when the operator releases his / her finger from the vehicle height button 57, the vehicle height button 57 returns to the initial position by a biasing force of a spring (not shown), and the traveling machine body 1 is maintained at the ground height at this time. It is possible to reduce the damage of the reaping device 3 and the like in contact with the road surface when the truck for transporting the combine is loaded onto or unloaded from the loading platform, or when the machine enters and leaves the field. Further, even on a steeply inclined road surface such as a walk board, it can be easily moved while preventing the fall of the combine.

  As apparent from the above description and FIGS. 6 to 10, 14, 16 and 17, according to the embodiment, the traveling machine body 1 supported by the left and right traveling units 2, and the left and right sides of the traveling machine body 1 A work vehicle including a rolling actuator 38 that changes the inclination posture of the direction, a pitching actuator 177 that changes the inclination posture of the traveling body 1 in the front-rear direction, and a controller 371 that controls the driving of the actuators 38 and 177. The controller 371 stores a pair of posture data ML and MR related to the posture of each traveling unit 2 in the traveling machine body 1, and the controller 371 uses the actuators 38 and 177 to perform the operations described above. Since whether or not the posture of the traveling machine body 1 can be changed is determined based on the both posture data ML and MR, both the posture data ML, it is possible to limit the movable range of the respective actuators 38,177 based on the MR. For this reason, the actuators 38 and 177 are not moved to the limit of movement to cause the traveling machine body 1 to be twisted, and the traveling machine body 1 is not brought into an extreme posture. realizable.

  The posture data ML and MR include a normal range AR2 and AR4 which are normal posture ranges and a limited range AR1, AR3 and AR5 to AR7 which are front and rear inclination ranges on the vehicle height upper limit side or lower limit side. The controller 371 determines whether or not the posture change of the traveling machine body 1 is possible depending on the combination of the limited ranges AR1, AR3, AR5 to AR7 of the posture data ML and MR. With reference to the combination of the restriction ranges AR1, AR3, AR5 to AR7 of the posture data ML, MR, the movable range of the actuators 38, 177 and thus the posture change of the traveling machine body 1 can be restricted. Therefore, while ensuring the responsiveness of the actuators 38 and 177, the traveling machine body 1 can be prevented from being twisted easily and reliably, and the posture changing operation of the traveling machine body 1 can be performed in a stable state as much as possible.

  Furthermore, a vehicle height operating tool 57 for changing the vehicle height of the traveling aircraft body 1 is provided on the wheel portion 51 of the steering round handle 11 disposed in front of the driver seat 12 on the traveling aircraft body 1, The steering column 46 that supports the steering round handle 11 is provided with a tilt operation tool 56 for changing the tilt posture of the traveling machine body 1, and the controller 371 manually operates the operation tools 56 and 57. Therefore, when the change of the posture of the traveling machine body 1 in the direction corresponding to the manual operation is prohibited, a notification to that effect is given. Therefore, an operation outside the posture range in which the responsiveness of the actuators 38 and 177 can be secured is performed. Can be actively informed. As a result, the actuators 38 and 177 can be smoothly driven within the posture range in which the responsiveness of the actuators 38 and 177 can be secured, and the vehicle height operation tool 57 and the tilt operation tool 56 can be manually operated. The posture changing operation of the traveling machine body 1 can be realized in a stable state as much as possible.

  The flowchart of FIG. 18 shows a specific control mode of the vehicle height raising / lowering operation (vehicle height raising operation and vehicle height lowering operation in FIG. 17) when the vehicle height button 57 is manually operated. In this case, the difference ΔHo = HRo−HLo between the left and right vehicle height sensors 375 and 376 at the start of raising / lowering is calculated (S01), and the left and right vehicle height adjustment hydraulic cylinders 38 are simultaneously driven in the same direction (S02). . Next, the left and right vehicle height sensors 375 and 376 values HLx and HRx are read again and updated (S03), and the difference ΔHx = HRx−HLx between the updated left and right vehicle height sensors 375 and 376 values HLx and HRx is calculated (S04). ). Then, it is determined whether or not the absolute value | ΔHx−ΔHo | of the difference between the updated difference ΔHx and the difference ΔHo at the start of lifting is equal to or greater than a preset first lifting reference value C1 (S05). Here, the first elevation reference value C1 is set to 20 mm, for example. In addition, you may include the 1st raising / lowering reference value C1 itself on the lower side, and may be included on the higher side. The embodiment is a case where it is included on the higher side. If the absolute value | ΔHx−ΔHo | is equal to or greater than the first lift reference value C1 (S05: yes), the vehicle height adjusting hydraulic cylinder 38 that has advanced in the moving direction first is stopped (S06). If it is less than the first raising / lowering reference value C1 (S05: no), the process proceeds to step S11 described later.

  After step S06 in which the vehicle height adjusting hydraulic cylinder 38 that has advanced in the moving direction first is stopped, the left and right vehicle height sensors 375 and 376 values HLx and HRx are read again and updated (S07), and then updated again. The difference ΔHx = HRx−HLx between the left and right vehicle height sensors 375 and 376 is calculated (S08). Then, it is determined whether or not the absolute value | ΔHx−ΔHo | of the difference between the difference ΔHx after re-update and the difference ΔHo at the start of lifting is equal to or larger than the second lifting reference value C2 that is smaller than the first lifting reference value C1. (S09). In the embodiment, the second elevation reference value C2 is set to 10 mm, for example. Note that the second elevation reference value C2 itself may also be included on the lower side or on the higher side. The embodiment is a case where it is included on the higher side. If the absolute value | ΔHx−ΔHo | is equal to or greater than the second elevation reference value C2 (S09: yes), the vehicle height adjustment hydraulic cylinder 38 that is stopped is redriven (S10). Then, if the manual operation of the vehicle height button 57 has been completed (S11: yes), both the left and right vehicle height adjustment hydraulic cylinders 38 are stopped (S12). If manual operation is continuing (S11: no), it will return to step S03.

  On the other hand, returning to step S09, if the absolute value | ΔHx−ΔHo | is less than the second elevation reference value C2 (S09: no), the vehicle height sensors 375 and 376 corresponding to the vehicle height adjustment hydraulic cylinder 38 being driven. Has reached the limit value (upper limit or lower limit) (S13: yes), the process proceeds to step S10, and the vehicle height adjusting hydraulic cylinder 38 being stopped is driven again. If the limit value has not been reached (S13: no), it is determined whether or not the manual operation of the vehicle height button 57 has ended (S14). If the manual operation has been completed (S14: yes), the process proceeds to step S12, and both the left and right vehicle height adjustment hydraulic cylinders 38 are stopped. If manual operation is continuing (S14: no), it will return to step S07.

  FIGS. 19A to 19D schematically show the lifting operation when the load on the left traveling crawler 2 side is large. FIG. 19A shows a case where the absolute value | ΔHx−ΔHo | becomes equal to or higher than the first elevation reference value C1 during the ascending operation. Here, the right vehicle height adjustment hydraulic cylinder 38 corresponding to the side that has advanced in the moving direction, that is, the height side is stopped, and the left vehicle height adjustment hydraulic cylinder 38 continues to extend (steps S05, S06). reference). FIG. 19B shows a case where the absolute value | ΔHx−ΔHo | becomes equal to or higher than the second elevation reference value C2 after the right vehicle height adjustment hydraulic cylinder 38 is stopped. In this case, the left vehicle height adjusting hydraulic cylinder 38 that is continuously driven increases the height of the left traveling crawler 2 side of the traveling body 1 so as to be excessively higher than the height of the right traveling crawler 2 side. The middle right vehicle height adjusting hydraulic cylinder 38 is driven again, and both the vehicle height adjusting hydraulic cylinders 38 are extended (see steps S09 and S10).

  FIG. 19C shows a case where the absolute value | ΔHx−ΔHo | becomes equal to or higher than the first elevation reference value C1 during the lowering operation. Here, the left vehicle height adjustment hydraulic cylinder 38 corresponding to the side that has advanced in the moving direction, that is, the low height side is stopped, and the right vehicle height adjustment hydraulic cylinder 38 continues the shortening movement (steps S05, S06). reference). FIG. 19D shows a case where the absolute value | ΔHx−ΔHo | becomes equal to or higher than the second elevation reference value C2 after the left vehicle height adjustment hydraulic cylinder 38 is stopped. In this case, the right vehicle height adjusting hydraulic cylinder 38 that is continuously driven causes the height on the right traveling crawler 2 side of the traveling machine body 1 to be excessively lower than the height on the left traveling crawler 2 side. The middle left vehicle height adjusting hydraulic cylinder 38 is driven again, and both the vehicle height adjusting hydraulic cylinders 38 are shortened (see steps S09 and S10).

  As is clear from the above description and FIGS. 18 and 19, according to the embodiment, the traveling machine body 1 supported by the left and right traveling units 2 and a pair of right and left inclined postures of the traveling machine body 1 are changed. A rolling actuator 38, a pair of pitching actuators 177 that change the tilting posture of the traveling machine body 1 in the front-rear direction, left and right vehicle height sensors 375, 376 that detect left and right heights in the traveling machine body 1, and the traveling machine body 1 is a work vehicle that includes left and right pitching sensors 382a and 382b that detect front and rear inclination angles in the left and right sides of the vehicle 1 when the vehicle height of the traveling machine body 1 is raised and lowered by manual operation. Between the difference ΔHx between the vehicle height sensors 375 and 376 and the difference ΔHo between the left and right vehicle height sensors 375 and 376 at the start of lifting When the absolute value | ΔHx−ΔHo | of the difference exceeds a preset first ascent / descent reference value C1, the rolling actuator 38 on the side that has advanced in the moving direction first is stopped, and the other rolling actuator 38 is driven. Since the vehicle height difference between the left and right sides of the traveling machine body 1 is greatly deviated from the vehicle height difference at the start of lifting, the rolling actuator 38 on the side that has advanced in the moving direction first is configured. Will be temporarily stopped. For this reason, regardless of the load applied to the pair of rolling actuators 38, the vehicle height of the traveling machine body 1 can be raised and lowered with the left and right inclination angles of the traveling machine body 1 maintained as constant as possible.

  When the absolute value | ΔHx−ΔHo | of the difference exceeds a second lift reference value C2 that is smaller than the first lift reference value C1, after stopping the one rolling actuator 38, the one rolling actuator 38 is used. Is constructed so as to re-drive the vehicle body 1, while smoothly absorbing the influence of the load applied to both the rolling actuators 38, the left-right inclination angle of the vehicle body 1 is maintained as constant as possible, and the vehicle body 1 is The vehicle height can be raised and lowered, and the lifting and lowering operation of the traveling machine body 1 can be stabilized.

  Further, after stopping the one rolling actuator 38, when the vehicle height sensors 375, 376 values HLx, HRx corresponding to the other rolling actuator 38 reach a limit value, the one rolling actuator 38 is driven again. Thus, both the rolling actuators 38 are driven even in an exceptional situation where the vehicle height upper limit or vehicle height lower limit is reached without exceeding the second lifting reference value C2. As a result, it is possible to achieve vehicle height elevating control that reliably and smoothly handles the vehicle.

  The flowchart in FIG. 20 shows a specific control mode of the forward / backward tilting operation (forward tilting operation and backward tilting operation in FIG. 17) when the posture operation lever 56 is tilted in the front / rear direction. In this case, the difference Δθo = θRo−θLo between the left and right pitching sensors 382a and 382b at the start of the forward / backward tilt is calculated (S21), and the difference Δθo is set to zero (θRo and θLo are the origins). After executing the correction (S22), the left and right front / rear tilt hydraulic cylinders 177 are simultaneously driven in the same direction (S23). Next, the left and right pitching sensors 382a and 382b values θLx and θRx are reread and updated (S24), and the difference Δθx = θRx−θLx between the updated left and right pitching sensors 382a and 382b values θLx and θRx is calculated (S25). Then, it is determined whether or not the absolute value | Δθx−Δθo | of the difference Δθx after the update and the difference Δθo at the start of the front / rear tilt is equal to or greater than a preset first tilt reference value φ1 (S26). Here, the first inclination reference value φ1 is set to 3 °, for example. The first inclination reference value φ1 itself may be included on the lower side or included on the higher side. The embodiment is a case where it is included on the higher side. If the absolute value | Δθx−Δθo | is equal to or larger than the first tilt reference value φ1 (S26: yes), the front / rear tilt hydraulic cylinder 177 that has advanced in the moving direction first is stopped (S27). If it is less than the first inclination reference value φ1 (S26: no), the process proceeds to step S32 described later.

  After step S27 in which the forward / backward tilt hydraulic cylinder 177 that has advanced in the moving direction is stopped, the left and right pitching sensors 382a and 382b values θLx and θRx are read again and updated (S28). A difference Δθx = θRx−θLx between the left and right pitching sensors 382a and 382b values θLx and θRx is calculated (S29). Then, it is determined whether or not the absolute value | Δθx−Δθo | of the difference Δθx after the re-update and the difference Δθo at the start of the front / rear tilt is equal to or larger than the second inclination reference value φ2 smaller than the first inclination reference value φ1 (S30). . In the embodiment, the second inclination reference value φ2 is set to 2 °, for example. The second inclination reference value φ2 itself may be included on the lower side or included on the higher side. The embodiment is a case where it is included on the higher side. If the absolute value | Δθx−Δθo | is equal to or greater than the second inclination reference value φ2 (S30: yes), the stopped forward / backward inclination hydraulic cylinder 177 is driven again (S31). Then, if the manual operation of the posture operation lever 56 is completed (S32: yes), both the left and right hydraulic cylinders 177 are stopped (S33). If manual operation is continuing (S32: no), it will return to step S24.

  On the other hand, when the absolute value | Δθx−Δθo | is less than the second tilt reference value φ2 (S30: no), the pitching sensors 382a and 382b corresponding to the forward / backward tilt hydraulic cylinder 177 are driven. If the limit value (forward tilt or rear tilt) is reached (S34: yes), the process proceeds to step S31, and the stopped front / rear hydraulic cylinder 177 is re-driven. If the limit value has not been reached (S34: no), it is determined whether or not the manual operation of the attitude control lever 56 has been completed (S35). If the manual operation has been completed (S35: yes), the process proceeds to step S33, and both the left and right hydraulic cylinders 177 are stopped. If manual operation is continuing (S35: no), it will return to step S28.

  21A to 21D schematically show the front / rear tilting operation when the load on the left traveling crawler 2 side is large. FIG. 21A shows a case where the absolute value | Δθx−Δθo | becomes equal to or larger than the first tilt reference value φ1 during the forward tilting operation. Here, the right front / rear tilt hydraulic cylinder 177 corresponding to the side that has advanced in the moving direction, that is, the side with the larger forward tilt angle, is stopped, and the left front / rear tilt hydraulic cylinder 177 continues to extend. (See steps S26 and S27). FIG. 21B shows a case where the absolute value | Δθx−Δθo | becomes equal to or greater than the second inclination reference value φ2 after the right front / rear inclination hydraulic cylinder 177 is stopped. Here, the forward tilt angle on the left traveling crawler 2 side in the traveling machine body 1 is larger than the forward tilt angle on the right traveling crawler 2 side by the left front / rear tilt hydraulic cylinder 177 during continued driving. (Because it is tilted forward), the right front / rear tilt hydraulic cylinder 177 that has been stopped is driven again, and both the front / rear tilt hydraulic cylinders 177 are extended (see steps S30 and S31).

  FIG. 21C shows the case where the absolute value | Δθx−Δθo | becomes equal to or greater than the first tilt reference value φ1 during the backward tilting operation. Here, the left front / rear tilt hydraulic cylinder 177 corresponding to the side that has advanced in the moving direction, that is, the side with the larger rearward tilt angle is stopped, and the right front / rear tilt hydraulic cylinder 177 continues the shortening motion. (See steps S26 and S27). FIG. 21D shows the case where the absolute value | Δθx−Δθo | becomes equal to or greater than the second inclination reference value φ2 after the left-hand front / rear inclination hydraulic cylinder 177 is stopped. In this case, the right forward crawler 2 side rearward tilt angle of the traveling machine body 1 is excessively larger than the rearward tilt angle of the left travel crawler 2 side by the right front and rear tilt hydraulic cylinder 177 during driving. Therefore, the left front / rear tilt hydraulic cylinder 177 is re-driven and both the front / rear tilt hydraulic cylinders 177 are shortened (see steps S30 and S31).

  As apparent from the above description and FIGS. 20 and 21, according to the embodiment, when the longitudinal inclination angle of the traveling machine body 1 is changed by a manual operation, the difference between the current left and right pitching sensors 382 a and 382 b values. When the absolute value | Δθx−Δθo | of the difference between Δθx and the difference Δθo between the left and right pitching sensors 382a and 382b at the start of the front / rear tilt exceeds a preset first tilt reference value φ1, the movement is first performed. Since the pitching actuator 177 on the side proceeding in the direction is stopped and the driving of the other pitching actuator 177 is continued, the difference between the left and right front and rear tilt angles in the traveling machine body 1 is When there is a large difference compared to the front / rear inclination angle difference, the pitching actuator 1 on the side that has advanced in the moving direction first. 7 Once in stopping the. Therefore, regardless of the load applied to the pair of pitching actuators 177, there is an effect that the front-rear inclination angle of the traveling machine body 1 can be changed in a state where the left-right inclination angle of the traveling machine body 1 is maintained as constant as possible. .

  When the absolute value | Δθx−Δθo | of the difference exceeds a second inclination reference value φ2 smaller than the first inclination reference value φ1 after stopping the one pitching actuator 177, the one pitching actuator 177 is output. Therefore, it is possible to maintain the left-right tilt angle of the traveling machine body 1 as constant as possible while smoothly absorbing the influence of the load applied to the two pitching actuators 177. It is possible to change the front / rear inclination angle of the vehicle, and the front / rear inclination operation of the traveling machine body 1 is stabilized.

  Further, after stopping the one pitching actuator 177, when the pitching sensors 382a, 382b values θLx, θRx corresponding to the other pitching actuator 177 reach a limit value, the one pitching actuator 177 is driven again. Therefore, both of the pitching actuators 177 can be driven even in an exceptional situation where the left or right forward tilt limit or the rearward tilt limit is reached without exceeding the second tilt reference value φ2. Thus, there is an effect that it is possible to realize the forward / backward tilt control that copes reliably and smoothly.

  The flowchart in FIG. 22 shows a specific control mode when the value of the left / right tilt sensor 374 suddenly changes in the left / right tilt control (left tilt operation and right tilt operation in FIG. 17). Note that an inclination operation prohibition flag F, which will be described later, is set to a reset state (F = 0) at the start of execution of inclination control. When the back switch 391 is in the on state (S41: yes) and the turning angle sensor 392 detects that the steering wheel handle 11 is out of the neutral state in which the steering wheel handle 11 is hardly operated (S42: yes), traveling Since the vehicle body 1 is turning left or right while moving backward, a change operation of the left-right inclination posture of the traveling vehicle body 1 by the automatic control of the vehicle height adjusting hydraulic cylinder 38, that is, left-right inclination control is prohibited (S43). When the back switch 391 is in the off state (S41: no) or the turning angle sensor 392 detects that the steering wheel handle 11 is in the neutral state (S42: no), the process proceeds to step S44 and the right / left tilt control is performed. Run. In the embodiment, the angular range of the neutral state of the steering round handle 11 is set to a size of about 15 ° to the left and right (total of 30 °) across the neutral position. The pivotable range of the steering round handle 11 is set to a size of about 135 ° to the left and right across the neutral position.

  In step S44, the left / right tilt sensor 374 value λ (x) is read at appropriate intervals. Next, the absolute value | λ (1) −λ (2) | of the difference between the left and right tilt sensor 374 value λ (1) read earlier and the left and right tilt sensor 374 value λ (2) read later is It is determined whether or not it is equal to or greater than the set left / right inclination threshold Λ (S45). The left / right inclination threshold value Λ in the embodiment is set to 3.5 °, for example. Note that the left / right slope threshold Λ itself may be included on the lower side or included on the higher side. Embodiments are included on the higher side.

  If the absolute value | λ (1) −λ (2) | is equal to or greater than the left / right inclination threshold Λ (S45: yes), whether the right / left inclination posture of the traveling machine body 1 is changing rapidly, vibrations of the traveling machine body 1, etc. If it is understood that the left / right tilt sensor 374 detects excessively, and the left / right tilt control is continued as it is, the traveling aircraft body 1 is excessively changed in posture in the left / right direction (hunting motion), and the riding comfort of the traveling aircraft body 1 is poor. It is considered to be. Therefore, if the tilt operation prohibition flag F is in the reset state (F = 0) (S46: yes), the right / left tilt posture changing operation of the traveling machine body 1 by the automatic control of the vehicle height adjusting hydraulic cylinder 38, that is, the left / right tilt control is performed. It is prohibited (S47). The tilt operation prohibition flag F is for determining whether or not the tilt operation of the traveling machine body 1 is forcibly prohibited during the previous tilt control. After prohibiting the left / right tilting operation, the tilting operation prohibiting flag F is set (F = 1), and the process returns to step S44. Even when the tilt operation prohibition flag F is in the set state (F = 1) in step S46 (S46: no), the process returns to step S44.

  Returning to step S45, when the absolute value | λ (1) −λ (2) | is less than the left / right tilt threshold Λ (S45: no), the tilt operation prohibition flag F is in the reset state (F = 0). If there is (S49: yes), the left or right vehicle height adjusting hydraulic cylinder 38 is operated to change the posture of the traveling machine body 1 in the left or right inclination direction (S50). In this case, if the traveling machine body 1 is tilted to the right, the left or right vehicle height adjusting hydraulic cylinder 38 is operated to raise the right side of the traveling machine body 1 or to lower the left side of the traveling machine body 1. Change the posture to the left tilt direction. If the traveling machine body 1 is tilted to the left, the left or right vehicle height adjusting hydraulic cylinder 38 is operated to lower the right side of the traveling machine body 1 or raise the left side of the traveling machine body 1 and tilt the traveling machine body 1 to the right. Change posture in the direction. The traveling machine body 1 is supported by the left / right inclination angle posture (ground horizontal posture) set by the right / left inclination setting device 377.

  If the tilt operation prohibition flag F is in the set state (F = 1) in step S49 (S49: no), if the transient time T is not being counted (S51: no), counting of the transient time T is started (S52). ). Then, if the transition time T has exceeded the preset first set time T1 (S53: yes), the right-and-left tilting posture is relatively slow for a relatively long time after the right-and-left tilting operation is once prohibited. Or the value of the left / right tilt sensor 374 is detected to be stable for a relatively long time. Therefore, after the tilt operation prohibition flag F is reset (F = 0) (S54), the process proceeds to step S50. It shifts and the left-right inclination operation | movement of the traveling body 1 is performed (it returns from a prohibition state). When the transition time T is less than the first set time T1 (S53: no), the process returns to step S44. Note that the set time To itself used in step S53 may be included on the shorter side or included on the longer side. In the embodiment, it is included on the higher side.

  As is apparent from the above description and FIG. 22, according to the embodiment, the traveling machine body 1 supported by the left and right traveling units 2 and a pair of rolling actuators 38 that change the inclined posture of the traveling machine body 1 in the left-right direction. A pair of pitching actuators 177 that change the tilting posture of the traveling machine body 1 in the front-rear direction, a left-right tilt sensor 374 that detects a tilting angle of the traveling machine body 1 in the left-right direction, and a tilt of the traveling machine body 1 in the front-rear direction A work vehicle including a front / rear inclination sensor 381 for detecting an angle, and during execution of left / right inclination control for changing the right / left inclination posture of the traveling machine body 1, the current right / left inclination sensor 374 value λ (2) and When the absolute value | λ (1) −λ (2) | of the difference from the immediately preceding right / left tilt sensor 374 value λ (1) exceeds a preset left / right tilt threshold Λ, Since the tilt control is prohibited (see Steps S45 to S47), for example, the left and right tilt posture of the traveling machine body 1 suddenly changes due to the inclination of a farm scene or the vibration of the traveling machine body 1 during traveling. Even if a sudden change state that changes or is detected excessively by the left / right tilt sensor 374 occurs, the left / right tilt control can be prohibited in conjunction with the occurrence of the sudden change state. For this reason, it is possible to prevent the traveling machine body 1 from excessively changing its posture (hunting movement) in the left-right direction, and the riding comfort of the traveling machine body 1 can be improved.

  Also, after the absolute value | λ (1) −λ (2) | of the difference exceeds the left / right inclination threshold value Λ, the absolute value | λ (1) −λ (2) | Since it is configured to return to the execution state of the left-right tilt control when the state below the threshold Λ passes a preset first set time T1, the occurrence of the sudden change state is generated (see steps S50 to S53). Even if the left-right tilt control is prohibited by the above, if the sudden change state is resolved, the operator can return to the left-right tilt control automatically and smoothly without any extra effort (operation), and the burden on the operator is reduced. There is an effect that it can be reduced.

  Further, when the traveling machine body 1 moves forward and backward including a left and right turn, execution of the left and right inclination control is permitted, and when the traveling machine body 1 makes a backward turn, the left and right inclination control is prohibited. (See steps S41 to S43), for example, even when only the traveling part 2 on one side is mounted on a kite or the like during reverse travel, the left and right inclined posture of the traveling machine body 1 can be maintained horizontally to the ground. The workability in the vehicle can be improved. When such a configuration is applied to, for example, a combine as a work vehicle, the harvesting and threshing workability can be improved with the combine. Further, since the left / right tilt control is prohibited during the backward turning of the traveling machine body 1, there is no possibility that the behavior of the traveling machine body 1 becomes unstable during the backward turning.

  Incidentally, in the embodiment, when the value of the front / rear tilt sensor 381 suddenly changes in the front / rear tilt control (the forward tilt operation and the rear tilt operation in FIG. 17), the front / rear tilt control is not specifically prohibited. In order to prevent hunting motion in the front-rear direction, it is possible to perform control so as to prohibit front-rear tilt control. The flowchart of FIG. 23 shows a specific control mode when the value of the front / rear tilt sensor 381 suddenly changes in the front / rear tilt control (the forward tilt operation and the rear tilt operation of FIG. 17). When the back switch 391 is in the on state (S61: yes) and the turning angle sensor 392 detects that the steering wheel handle 11 is out of the neutral state in which the steering wheel handle 11 is hardly operated (S62: yes), traveling Since the vehicle body 1 is turning left or right while moving backward, the forward / backward tilt posture changing operation of the traveling vehicle body 1 by the automatic control of the forward / backward tilt hydraulic cylinder 177, that is, forward / backward tilt control is prohibited (S63). When the back switch 391 is in the off state (S61: no) or the turning angle sensor 392 detects that the steering wheel handle 11 is in the neutral state (S62: no), the process proceeds to step S64 and the forward / backward tilt control is performed. Run.

  In step S64, the forward / backward tilt sensor 381 value η (x) is read appropriately every short time. Next, the absolute value | η (1) −η (2) | of the difference between the front and rear inclination sensor 381 value η (1) read earlier and the front and rear inclination sensor 381 value η (2) read later is It is determined whether or not the set forward / backward inclination threshold value Η is exceeded (S65). The front / rear inclination threshold value 傾斜 in the embodiment is set to 3.5 °, for example. Note that the front / rear inclination threshold value Η itself may be included on the lower side or included on the higher side. Embodiments are included on the higher side.

  If the absolute value | η (1) −η (2) | is equal to or greater than the front / rear tilt threshold value Η (S65: yes), whether the front / rear tilt posture of the traveling vehicle body 1 is changing rapidly, vibrations of the traveling vehicle body 1, and the like. If it is understood that the forward / backward tilt sensor 381 detects excessively, and the forward / backward tilt control is continued as it is, the traveling aircraft body 1 is excessively changed in posture in the longitudinal direction (hunting motion), and the riding comfort of the traveling aircraft body 1 is poor. It is considered to be. Therefore, if the tilt operation prohibition flag F is in the reset state (F = 0) (S66: yes), the forward / backward tilt posture changing operation of the traveling machine body 1 by the automatic control of the forward / backward tilt hydraulic cylinder 177, that is, the front / back tilt control is performed. It is prohibited (S67). After prohibiting the forward / backward tilting operation, the tilting operation prohibiting flag F is set (F = 1) and the process returns to step S64. Even when the tilt operation prohibition flag F is in the set state (F = 1) in step S66 (S66: no), the process returns to step S64.

  Now, returning to step S65, when the absolute value | η (1) −η (2) | is less than the front / rear inclination threshold value Η (S65: no), the inclination operation prohibition flag F is in the reset state (F = 0). If there is (S69: yes), the left and right forward / backward tilt hydraulic cylinders 177 are actuated to change the posture of the traveling machine body 1 in the forward or backward tilt direction (S70). That is, the rear side of the traveling machine body 1 inclined to the rear side is raised, or the rear side of the traveling machine body 1 inclined to the front side is lowered. The traveling machine body 1 is supported by the front / rear inclination angle posture (horizontal ground posture) set by the front / rear inclination setter 383.

  If the tilt operation prohibition flag F is in the set state (F = 1) in step S69 (S69: no), if the transient time T is not being counted (S71: no), counting of the transient time T is started (S72). ). If the transition time T has exceeded the preset second set time T2 (S73: yes), the forward and backward tilting operation is once prohibited, but the forward and backward tilting posture of the traveling machine body 1 is then slowed for a relatively long time. Or the value of the front / rear tilt sensor 381 is detected to be stably detected for a relatively long time. Therefore, after the tilt operation prohibition flag F is set to the reset state (F = 0) (S74), the process proceeds to step S70. It shifts and the front-back inclination operation | movement of the traveling body 1 is performed (it returns from a prohibition state). When the transition time T is less than the second set time T2 (S73: no), the process returns to step S64.

  As is apparent from the above description and FIG. 23, during the execution of the forward / backward tilt control for changing the forward / backward tilt posture of the traveling machine body 1, the current forward / backward tilt sensor 381 value η (2) and the immediately preceding front / back tilt sensor 381. When the absolute value | η (1) −η (2) | of the difference from the value η (1) exceeds a preset front / rear inclination threshold value Η, the front / rear inclination control is prohibited ( Steps S65 to S67), for example, due to the inclination of a farm scene or the vibration of the traveling machine body 1 during traveling, the forward / backward inclination posture of the traveling machine body 1 changes suddenly, or the front / rear inclination sensor 381 detects excessively. Even if a sudden change state occurs, the front-rear tilt control can be prohibited in conjunction with the occurrence of the sudden change state. For this reason, it can suppress that the said traveling body 1 changes an attitude | position (hunting movement) excessively in the front-back direction, and there exists an effect that the riding comfort of the said traveling body 1 can be aimed at.

  Also, after the absolute value of the difference | η (1) −η (2) | once exceeds the front / rear inclination threshold Η, the absolute value of the difference | η (1) −η (2) | Since it is configured to return to the execution state of the forward / backward tilt control when the state below the threshold value を passes a preset second set time T2, the occurrence of the sudden change state occurs (see Steps S70 to S73). Even if the forward / backward tilt control is prohibited by the above, if the sudden change state is resolved, the operator can return to the forward / backward tilt control automatically and smoothly without any extra effort (operation), and the burden on the operator is reduced. There is an effect that it can be reduced.

  Further, the forward / backward tilt control is allowed to be executed when the traveling machine body 1 is moving forward and backward including a left / right turn, while the forward / backward tilt control is prohibited during the backward turning of the traveling machine body 1. (See Steps S61 to S63), for example, even when only one traveling part 2 rides on a saddle or the like during reverse travel, the traveling body 1 can maintain the front and rear inclined posture to be horizontal to the ground. The workability in the vehicle can be improved. When such a configuration is applied to, for example, a combine as a work vehicle, the harvesting and threshing workability of the combine can be improved. Further, since the forward / backward tilt control is prohibited during the backward turning of the traveling machine body 1, there is no possibility that the behavior of the traveling machine body 1 becomes unstable during the backward turning.

1 traveling machine body 2 traveling crawler (traveling section)
14 Diesel engine 21 Truck frame 38 Vehicle height adjustment hydraulic cylinder (rolling actuator)
56 Posture control lever (tilt control tool)
57 Vehicle height button (Vehicle height operation tool)
177 Hydraulic cylinder for forward / backward tilting (pitching actuator)
374 Left / right tilt sensor 381 Front / back tilt sensor

Claims (5)

A traveling machine body supported by left and right traveling units, a pair of rolling actuators for changing a lateral inclination posture of the traveling machine body, a pair of pitching actuators for changing a longitudinal inclination posture of the traveling body, and A work vehicle comprising a left / right tilt sensor that detects a tilt angle in a left / right direction of a traveling machine body, and a front / rear tilt sensor that detects a tilt angle in the front / rear direction of the traveling machine body,
During the execution of the left / right tilt control for changing the left / right tilt posture of the traveling machine body, when the absolute value of the difference between the current left / right tilt sensor value and the immediately preceding left / right tilt sensor value exceeds a preset left / right tilt threshold value, It is configured to prohibit the left / right tilt control,
Work vehicle. After the absolute value of the difference once exceeds the left-right inclination threshold, when the state in which the absolute value of the difference is lower than the left-right inclination threshold exceeds a preset first setting time, the left-right inclination control is executed. Configured to return,
The work vehicle according to claim 1. During the execution of the front / rear tilt control for changing the front / rear tilt posture of the traveling machine body, when the absolute value of the difference between the current front / rear tilt sensor value and the previous front / rear tilt sensor value exceeds a preset front / rear tilt threshold, Configured to prohibit the front-rear tilt control;
The work vehicle according to claim 1 or 2. After the absolute value of the difference once exceeds the front / rear inclination threshold, when the state where the absolute value of the difference falls below the front / rear inclination threshold exceeds a preset second set time, the execution state of the front / rear inclination control is set. Configured to return,
The work vehicle according to claim 3. At the time of reverse turning of the traveling machine body, the left and right inclination control is prohibited.
The work vehicle according to any one of claims 1 to 4.

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