JP2008079563A - Device for controlling attitude of working vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a devicefor controlling attitude of working device which can reduce the vehicle body attitude-changing speed for preventing deterioration of ride comfort, when the attitude of the vehicle body with respect to a travel unit does not have the risk of changing by a large amount, and can quickly perform attitude change operation, when the attitude of the vehicle body with respect to the travel unit is changed by a large amount. <P>SOLUTION: This working vehicle attitude control device is equipped with a plurality of driving means, capable of lifting or lowering one side position and the other side position separated in an inclination angle-changing direction on the vehicle body, on the basis of the grounding portion of the travel device; performing attitude change control for controlling the driving means to keep an inclination angle with respect to the horizontal standard surface of the vehicle body to a set inclination angle, on the basis of the detection information of inclination angle detection means; performing a single-side driving type attitude change operation, when it is discriminated as not being an attitude change timing where a large change in the vehicle body attitude with respect to the travel unit is predicted; and performing a both-side driving type attitude change operation, when it is discriminated as being an attitude change timing. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a posture change operation means that can freely change the posture of a vehicle body with respect to a traveling device, a posture control means that controls the operation of the posture change operation means, and an inclination angle detection that detects an inclination angle of the vehicle body with respect to a horizontal reference plane. A plurality of drive means that can move up and down each of the one end portion and the other end portion of the vehicle body separated from each other in the inclination angle changing direction with respect to the grounding portion of the traveling device. The attitude control means operates the attitude change operation means so that the inclination angle with respect to the horizontal reference plane of the vehicle body is maintained at the set inclination angle based on the detection information of the inclination angle detection means. The present invention relates to an attitude control device for a work vehicle configured to execute attitude change control to be controlled.

Conventionally, the attitude control device for a work vehicle having the above configuration has been configured as follows.
That is, for example, the posture changing operation means is configured to freely change the front and rear posture of the vehicle body with respect to the traveling device, and the grounding portion of the traveling device is separately provided for each of the front side portion of the vehicle body and the rear side portion of the vehicle body. For example, the control means is configured to maintain the front-rear inclination angle with respect to the horizontal reference plane of the vehicle body at the set front-rear inclination angle as posture change control. The other drive means in a state in which one of the drive means located on the front side and the drive means located on the rear side of the plurality of drive means is stopped. It came to drive (for example, refer patent document 1). That is, ascending / descending one of the one end side and the other end side of the vehicle body in the direction of changing the inclination angle is stopped, and the other is moved up and down so that the front / rear inclination angle with respect to the horizontal reference plane of the vehicle body becomes the set inclination angle Was configured to let.

JP 2002-204613 A

  In the above conventional configuration, for example, when changing the front-rear inclination angle of the vehicle body, always stop raising or lowering one of the one end side position or the other end side position away from the inclination angle change direction in the vehicle body, The other is raised and lowered so that the front / rear tilt angle with respect to the horizontal reference plane of the vehicle body becomes the set inclination angle, so that the posture change speed does not become too fast when the vehicle body posture change operation is performed, and the riding comfort is lowered. It is intended to prevent this. In other words, the unevenness of the normal ground is not so large, and it is possible to perform the posture change operation without increasing the posture change speed of the vehicle body, so the posture change speed of the vehicle body becomes too fast. This prevents the ride comfort from decreasing.

  However, in the above-described conventional configuration, in the combine as an example of the work vehicle, for example, the operation of the attitude changing operation unit is controlled so that the inclination angle with respect to the horizontal reference plane in the longitudinal direction of the vehicle body is maintained at the set inclination angle. When configured to execute posture change control, there are the following disadvantages in performing actual work in the field, and there is room for improvement.

  For example, in a combine, after traveling along one work process, the vehicle switches from a forward state to a forward state after moving a set distance in an oblique direction so as to go to the next work process having a different orientation of about 90 degrees. In this case, if the forward travel is stopped and then switched to the reverse state, the vehicle body tends to lean forward, and if the reverse travel is stopped and then switched to the forward state, the vehicle body However, there is a possibility that the posture change operation may be delayed because the vehicle body is greatly inclined when switching from the reverse state to the forward state.

  When the explanation is added, for example, in a case where a farming field M having a rectangular section as shown in FIG. As shown in (2), when cutting and traveling with forward travel, the front side of the traveling device is scraped with mud and the front side is lifted and the vehicle body front-rear posture tends to be tilted backward, but posture change control is executed. As a result, the front-and-rear posture of the machine body is controlled to be in a horizontal state, and the cutting operation can be performed by lowering the cutting unit. Then, when the harvesting travel along one work process (the position of A in FIG. 14) is finished, the harvesting part is raised and moved to the start end of the next work process while changing the direction by 90 degrees. First, reverse travel is started after stopping forward travel (position b in FIG. 14). At this time, mud is poured into the rear side of the traveling device, the rear side is lifted, and the vehicle body front / rear posture becomes a forward leaning posture, but also in this case, contact with the mud can be avoided by greatly raising the mowing unit . Then, in the reverse travel state (position C in FIG. 14), as shown in FIG. 13C, the front-and-rear posture of the aircraft is operated by raising the front side of the aircraft with respect to the grounding portion of the traveling device by posture change control. Then, after the backward traveling is stopped, the forward traveling is started toward the starting end portion of the next work process (the position indicated by “D” in FIG. 14). ) As shown in the figure, the aircraft's front-rear posture is tilted backward. Also at this time, the posture change control is executed so that the longitudinal posture of the aircraft is controlled to be in a horizontal state.

  However, when the field is a wet field, in the headland where the turning operation with the forward / reverse switching as described above is performed, the field scene may be particularly weakened by being damaged by the traveling device, As described above, the forward / backward posture of the vehicle body cannot be controlled to the horizontal posture in spite of the posture change control so that the front / rear posture of the vehicle body becomes the horizontal posture when traveling backward, and the forward leaning posture may occur. . That is, the one end side portion of the vehicle body is at the uppermost position where it is most elevated with respect to the grounding portion of the traveling device, and the other end side portion of the vehicle body is most lowered with respect to the grounding portion of the traveling device. In spite of the lowermost position, the forward tilt posture is detected based on the detection information of the tilt angle sensor instead of the horizontal posture.

  When the forward traveling is started toward the start end of the next work process after the backward traveling is stopped, the front-rear posture of the machine body becomes the backward inclined posture, but as described above, the posture change control is performed when traveling backward. However, when the front-rear posture of the vehicle body is a forward leaning posture, the vehicle body is greatly inclined backward when starting forward traveling. At this time, when forward traveling is started, posture change control is executed. However, in the above-described conventional configuration, raising / lowering of one of the one end side portion and the other end side portion of the vehicle body is stopped and the other is raised / lowered. Therefore, it takes time to correct the posture of the vehicle body.

  As a result, when the forward travel is started toward the starting end of the next work stroke after the backward travel is stopped, as described above, the vehicle body is largely tilted backward at the start of forward travel. Since it takes time to correct the posture of the vehicle body, it takes time to correct the vehicle's front-rear posture to a posture suitable for the mowing work after starting forward travel, and the start of the mowing work is delayed. There were disadvantages such as.

  The object of the present invention is to prevent the vehicle posture from changing relative to the traveling device while preventing the ride comfort from deteriorating by slowing down the vehicle body posture changing speed when there is little possibility that the vehicle posture is greatly changed with respect to the traveling device. An object of the present invention is to provide an attitude control device for a work vehicle that can perform an attitude change operation quickly in the case of a large change.

A posture control device for a work vehicle according to the present invention includes a posture change operation means that can freely change a posture of a vehicle body with respect to a traveling device, a posture control means that controls the operation of the posture change operation means, and a horizontal reference plane of the vehicle body. An inclination angle detecting means for detecting the inclination angle,
The posture changing operation means is configured to include a plurality of driving means capable of moving up and down with respect to the grounding part of the traveling device at one end side position and the other end side position apart in the inclination angle changing direction in the vehicle body,
Based on the detection information of the inclination angle detection means, the attitude control means controls the operation of the attitude change operation means so that the inclination angle with respect to the horizontal reference plane of the vehicle body is maintained at the set inclination angle. The first feature configuration is configured to execute,
Posture variation timing determination means for determining whether or not the posture variation timing is predicted to greatly change the posture of the vehicle body with respect to the traveling device;
In the posture change control, the posture control means
When the posture variation timing determining means determines that it is not the posture variation timing, one of the one end side portion and the other end side portion of the vehicle body is lifted and stopped, and the other one with respect to the horizontal reference plane of the vehicle body Performing a one-sided drive type posture changing operation for operating a part of the plurality of driving means so as to move up and down so that the inclination angle becomes a set inclination angle; and
When the posture variation timing determining means determines that it is the posture variation timing, the inclination angle with respect to the horizontal reference plane of the vehicle body simultaneously becomes the set inclination angle at the one end side portion and the other end side portion of the vehicle body. In order to move up and down, a posture change operation of a double-sided drive type that operates each of the plurality of driving means is performed.

  According to the first characteristic configuration, when the posture control means executes the posture change control, it is not the posture change timing predicted by the posture change timing determination means that the posture of the vehicle body with respect to the traveling device is greatly changed. When it is determined, one of the one end side location and the other end side location in the vehicle body is raised and stopped, and the other is raised and lowered so that the inclination angle with respect to the horizontal reference plane of the vehicle body becomes a set inclination angle. One-side drive type posture changing operation for operating a part of the plurality of drive means is executed.

  In this way, when it is predicted that the posture of the vehicle body with respect to the traveling device does not change significantly, by executing the one-side drive type posture changing operation, either the one end side location or the other end side location of the vehicle body is determined. Since such a part is stopped up and down, the vehicle body posture change speed can be slowed to prevent a decrease in riding comfort.

  Then, when it is determined by the posture change timing determining means that the posture change timing is predicted to greatly change the posture of the vehicle body with respect to the traveling device, the one end side portion and the other end side portion of the vehicle body are simultaneously In order to raise and lower the tilt angle with respect to the horizontal reference plane to the set tilt angle, a posture change operation of a double-side drive type that operates each of the plurality of drive means is executed. When the posture of the vehicle body with respect to the traveling device is predicted to change greatly in this way, the amount of lifting operation by the driving means is less than that in the case of the one-side drive type by executing the posture change operation of the double-side drive type. In other words, if the operation speed by the driving means is the same, the tilt angle of the vehicle body can be returned to the set tilt angle in a shorter time.

  Therefore, according to the first characteristic configuration, when there is little possibility that the posture of the vehicle body with respect to the traveling device is greatly changed, the traveling device is prevented from slowing down the posture changing speed of the vehicle body and preventing the ride comfort from being lowered. When the posture of the vehicle body with respect to the vehicle changes greatly, it has become possible to provide a posture control device for a work vehicle that can quickly change the posture.

In addition to the first feature configuration, the second feature configuration of the present invention is configured such that the posture change operation means changes the front-rear inclination angle with respect to the horizontal reference plane of the vehicle body,
The tilt angle detecting means is configured to detect a front / rear tilt angle with respect to a horizontal reference plane of the vehicle body;
The posture control means controls the posture change operation means as the posture change control so that the front / rear inclination angle with respect to the horizontal reference plane of the vehicle body is set to the set front / rear inclination angle based on the detection information of the inclination angle detection means. It is in the point which is comprised.

  According to the second characteristic configuration, since the posture changing operation means is controlled so that the front-rear inclination angle with respect to the horizontal reference plane of the vehicle body becomes the set front-rear inclination angle based on the detection information of the inclination angle detection means, The front-rear posture of the vehicle body is changed so that the front-rear inclination angle with respect to the horizontal reference plane becomes the set front-rear inclination angle. As described above, when the vehicle body posture changes with respect to the traveling device when the vehicle body posture is changed, the posture change operation can be quickly performed.

  According to a third characteristic configuration of the present invention, in addition to the second characteristic configuration, the posture variation timing determination means is arranged at an uppermost position where the one end side portion of the vehicle body is most elevated with respect to the grounding portion of the traveling device. And the other end side portion of the vehicle body is in the lowest position where it is most lowered with respect to the grounding portion of the traveling device, and based on the detection information of the inclination angle detection means, When an inclined state in which the one end portion is located below the other end portion is detected, it is determined that it is the posture variation timing.

  For example, after the work vehicle travels forward along one work stroke in a soft field, the work vehicle moves backward in an oblique direction so as to go to the next work stroke having a different orientation of about 90 degrees, and then switches to the forward movement state. In the case of adopting such a work form, the vehicle body front-rear posture may become a forward leaning posture when traveling backward. At this time, when the vehicle is largely tilted forward, the front end side portion of the vehicle body is at the uppermost position where it is most elevated with respect to the grounding portion of the traveling device, and the rear end side portion of the vehicle body is the most relative to the grounding portion of the traveling device. Despite being in the lowermost position where it is descending, it does not become a horizontal posture, but based on the detection information of the tilt angle sensor, it detects the forward leaning posture where the front end side location on the vehicle body is located below the rear end side location May be.

  In addition, not only when switching from reverse travel to forward travel, for example, when the vehicle is moved forward, the vehicle travels over the ridge and enters the field. Despite being at the uppermost position where it is most elevated with respect to the grounding part of the device, and the rear end side location in the vehicle body is at the lowest position where it is most lowered relative to the grounding part of the traveling device, There is a possibility that a forward leaning posture in which the front end side portion of the vehicle body is located below the rear end side portion is detected based on the detection information of the tilt angle sensor, without being in a horizontal posture.

  Therefore, in such a case, it is determined that it is the posture variation timing, and the posture changing operation is performed quickly during forward traveling performed thereafter by executing the posture changing operation of the double-side drive type. Can do it.

  According to a fourth feature configuration of the present invention, in addition to the second feature configuration, it is detected that the posture variation timing determination means has changed from a state in which the vehicle body travels forward to a state in which the vehicle travels backward within a set time. Alternatively, when it is detected that the vehicle body has changed from a state of traveling backward to a state of traveling forward within a set time, the posture variation timing is determined.

  According to the fourth feature configuration, when changing the front-rear posture of the vehicle body, it is detected that the vehicle body has changed from a state of traveling forward to a state of traveling backward within a set time, or the vehicle body is traveling backward. When it is detected that the vehicle has changed from the running state to the forward running state within the set time, it is determined that it is the posture variation timing.

  For example, when performing a work, after traveling forward along one work process, after moving backward from the forward direction in an oblique direction so as to go to the next work process with a different orientation of about 90 degrees, it is switched to the forward process. There is a case where the work form is changed, but in such a work form, the state where the vehicle body travels forward changes from the state where the vehicle body travels backward within a set time, or the state where the vehicle body travels backward. It will change to a state of traveling forward within the set time, but in such a case, it is determined that it is the posture change timing, and the posture change is performed quickly by executing the posture change operation of the double-side drive type. The operation can be performed.

According to a fifth feature configuration of the present invention, in addition to the first feature configuration, the posture change operation means is configured to change and operate a right / left inclination angle with respect to a horizontal reference plane of the vehicle body,
The tilt angle detecting means is configured to detect a left / right tilt angle with respect to a horizontal reference plane of the vehicle body;
The posture control means controls the posture change operation means as the posture change control based on the detection information of the left / right inclination angle detection means so that the left / right inclination angle with respect to the horizontal reference plane of the vehicle body becomes a set left / right inclination angle. Configured as
Travel speed detection means for detecting the drive speed of the travel device is provided,
If the driving speed of the traveling device detected by the traveling speed detecting means is greater than or equal to a set value based on the detection information of the traveling speed detecting means, the attitude variation timing determining means is the attitude variation timing. It is in the point comprised so that it may distinguish.

  According to the fifth characteristic configuration, the posture changing operation means is controlled based on the detection information of the left / right inclination angle detection means so that the right / left inclination angle with respect to the horizontal reference plane of the vehicle body becomes the set left / right inclination angle. The left-right posture of the vehicle body is changed so that the left-right inclination angle with respect to the horizontal reference plane becomes the set left-right inclination angle. Thus, when changing the left-right posture of the vehicle body, if the posture of the vehicle body with respect to the traveling device changes greatly, the posture change operation can be quickly performed.

  Then, if the driving speed of the traveling device is equal to or higher than the set value, the posture variation timing determining means determines that it is the posture variation timing. In other words, when the vehicle body is traveling on a field with many irregularities, if the vehicle body travels at a high speed, the left-right inclination angle with respect to the horizontal reference plane of the vehicle body is likely to change greatly. When the vehicle is traveling in a high speed state as described above, it is possible to quickly perform the posture change operation by determining that it is the posture change timing and executing the posture change operation of the double-side drive type.

  Therefore, according to the fifth characteristic configuration, when the vehicle body is largely inclined to the left and right by traveling at a high speed, it is possible to quickly perform the posture changing operation, and to quickly perform the right and left inclination angle with respect to the horizontal reference plane of the vehicle body. Can be set to a tilt angle before and after setting.

Hereinafter, a case where the first embodiment of the present invention is applied to a combine as an example of a work vehicle will be described with reference to the drawings.
As shown in FIG. 1, the combine includes a pair of left and right crawler type traveling devices 1 </ b> R and 1 </ b> L, a threshing device 3 that threshs the harvested cereal, a grain tank 4 that stores the threshed grain, and a boarding operation unit 2. The harvesting part 10 which harvests planted cereals such as rice and wheat and supplies it to the threshing device 3 with respect to the vehicle body V provided with the above and the like is configured to be movable up and down.

  The cutting unit 10 includes a weeding tool 6 provided at the tip, a pulling device 5 that causes a planted culm that has been weeded by the weeding tool 6, and a clipper type that cuts the stock side of the induced culm. The cutting blade 7 and the vertical conveying device 8 that conveys the harvested cereal rice cake to the rear side while gradually changing the posture to the horizontal position, and the hydraulic cutting cylinder around the horizontal axis P1 at the front of the vehicle body V It is provided to be swingable up and down by C1.

  At the starting end of the vertical conveying device 8, there is provided a stock sensor 53 that is turned on when it comes into contact with the harvested cereal mash and is turned off when it is not in contact with the harvested cereal. Further, an ultrasonic cutting height sensor 9 for detecting the height of the cutting unit 10 with respect to the ground is provided at the rear side portion of the weeding tool 6. Although not described in detail, the cutting height sensor 9 detects the height of the cutting unit 10 with respect to the ground by measuring the time from when the ultrasonic wave is transmitted downward to when it is received. It is configured in a non-contact manner.

The combine is provided with posture changing operation means 100 that can freely change the front-rear inclination angle and the left-right inclination angle of the vehicle body V with respect to the grounding portions of the left and right traveling apparatuses 1R, 1L. Hereinafter, the configuration will be described.
First, a structure for attaching the left and right traveling apparatuses 1R and 1L to the vehicle body V will be described. Since the left and right traveling apparatuses 1R and 1L have the same configuration, the left traveling apparatus 1L will be described below, and the description of the right traveling apparatus 1R will be omitted.

  As shown in FIG. 2, a drive sprocket 13 is rotatably supported on the front end side of the support frame 12 fixed to the main frame 11 that constitutes the vehicle body V in the front-rear-facing posture, and a plurality of idle rotations. A track frame 16 that pivots in a state where the ring bodies 14 are arranged in the front-rear direction and supports a tension ring body 15 at the rear end portion is mounted on the support frame 12 so as to be movable up and down. A crawler belt B, which is an endless rotating body, is wound around the drive sprocket 13, the tension ring body 15, and each idler ring body 14.

A front bell crank 17a configured to be substantially L-shaped in a side view so as to be rotatable around a horizontal axis P2 is pivotally supported on the front side of the support frame 12, and a horizontal axis is provided on the rear side of the support frame 12. A rear bell crank 17b configured to be substantially L-shaped in a side view so as to be rotatable around P3 is pivotally supported. The lower end portion of the front bell crank 17a is pivotally connected to the front portion of the track frame 16, and the lower end portion of the rear bell crank 17b is connected to the track frame 16 via an auxiliary link 17b1 for absorbing the stroke. It is pivotally connected to the rear part.
On the other hand, the cylinder rods of the hydraulic cylinders C2 and C3 are connected to the upper end portions of the front and rear bell cranks 17a and 17b, respectively. The cylinder main body side of each of the hydraulic cylinders C2 and C3 is pivotally connected to the horizontal frame portion of the main frame 11, and each of the hydraulic cylinders C2 and C3 is constituted by a double-acting hydraulic cylinder.

  When the hydraulic cylinder C2 (hereinafter referred to as the left front cylinder) corresponding to the front bell crank 17a is most extended and the hydraulic cylinder C3 (hereinafter referred to as the left rear cylinder) corresponding to the rear bell crank 17b is most shortened, FIG. As shown, the track frame 16 is received and supported by the support frame 12, and the track frame 16 comes closest to the main frame 11 and becomes substantially parallel. This state is called the lower limit reference posture.

  When the left front cylinder C2 is shortened while maintaining the left rear cylinder C3 as it is in the lower limit reference posture, the front side of the vehicle body V is separated from the grounding portion as shown in FIG. The posture is changed in the direction of movement (i.e., a forward ascending operation). When the left rear cylinder C3 is extended while maintaining the left front cylinder C2 as it is in the lower limit reference posture, the rear side of the vehicle body V is separated from the grounding portion as shown in FIG. The posture is changed in the direction (after-lifting operation). When the left front cylinder C2 is shortened and the left rear cylinder C3 is extended from the lower limit reference posture, as shown in FIG. 5, the vehicle body V is separated from the ground contact portion in a parallel posture. The posture will be changed (ascending operation) in the direction.

  Similarly, the right traveling apparatus 1R includes a right front cylinder C4 positioned on the front side of the fuselage and a right rear cylinder C5 positioned on the rear side of the fuselage, and performs the same operation as that of the left traveling apparatus 1L. .

  Therefore, the posture changing operation means 100 can change and adjust the heights of the left and right traveling devices 1R and 1L with respect to the grounding portions at the left front, left rear, right front, and right rear in the vehicle body V, respectively. The four hydraulic cylinders C2 to C5 for changing the attitude of the airframe are provided as four driving means.

  Based on the amount of rotation of the four hydraulic cylinders C2, C3, C4, C5 corresponding to the rotation fulcrums of the bell cranks 17a, 17b in the left and right traveling devices 1R, 1L. The potentiometer type stroke sensors 18, 19, 20, 21 are provided for detecting the operation amount (that is, the stroke amount of the expansion / contraction operation) of each of the hydraulic cylinders C2, C3, C4, C5 (see FIG. 8). .

  Next, the power transmission system is shown in FIG. The power output from the engine E mounted on the vehicle body V is transmitted to the threshing device 3 via the threshing clutch 45 and travels to the left and right via the traveling clutch 46 and the continuously variable transmission 47 as the traveling transmission device. The power transmitted to the transmission unit 48 of the devices 1R and 1L and transmitted to the transmission unit 48 is transmitted to the traveling devices 1R and 1L and also transmitted to the cutting unit 10 via the cutting clutch 49. In the figure, reference numeral 50 denotes a vehicle speed sensor as a traveling speed detecting means for detecting the vehicle speed based on the input rotational speed to the mission unit 48.

  The continuously variable transmission 47 is configured to be shifted by a shift lever 51 provided in the boarding operation unit 2, and is provided with a potentiometer type shift lever sensor 52 that detects an operation position of the shift lever 51. Yes. That is, a trunnion shaft for speed change operation (not shown) in the continuously variable transmission 47 and the speed change lever 51 are mechanically linked via a link, and the speed change lever 51 is manually operated to move the continuously variable speed change apparatus 47 in the forward direction. In addition, the speed change operation can be performed steplessly in each of the reverse directions.

The combine is provided with a gravity-type front / rear inclination angle sensor 24 for detecting the front / rear inclination angle with respect to the horizontal reference plane of the vehicle body V by the action of gravity. It is configured as follows.
That is, as shown in FIG. 7, a liquid 42 having a predetermined viscosity made of silicon oil or the like is accommodated in a rectangular container 41 fixed to the vehicle body V, and metal plates having the same shape are parallel to each other at the same interval. Two pairs of detection electrodes 43 erected are arranged in a state of being fixed to the container 41 with an interval in the inclination angle detection direction (left-right direction in FIG. 7). When the liquid 42 is returned to the initial posture (liquid level horizontal state) due to gravity, when the vehicle body V is not inclined, the two sets of detection electrodes 43 are in the same immersion state (the state of FIG. 7). In the state where the vehicle body V is inclined, the immersion state of the two sets of detection electrodes 43 is different. The capacitance of each detection electrode 43 is measured, and the difference between the measured values (the vehicle body V is inclined). The conversion circuit unit 44 converts the detection value corresponding to the inclination angle information into zero.

  In addition, a gravity-type left / right tilt angle sensor 23 for detecting the left / right tilt angle with respect to the horizontal reference plane of the vehicle body V by the action of gravity is also provided. This is the same configuration as the forward / backward inclination angle sensor 24.

  As shown in FIG. 8, a microcomputer-based control device 22 is provided. The control device 22 includes the stroke sensors 18 to 21, a cutting height sensor 9, a left / right inclination angle sensor 23, a front / rear inclination angle sensor 24, Each detection information of the vehicle speed sensor 50, the shift lever sensor 52, and the stock sensor 53 is input. The operation panel of the boarding operation unit 2 is provided with an automatic on / off switch 27 for instructing on / off of automatic posture control described later, and operation information thereof is also input to the control device 22. Further, on the operation panel of the boarding operation unit 2, a volume-type cutting height setting device 39 for setting the height of the cutting unit 10 with respect to the vehicle body V with respect to the ground, that is, a cutting height, an ascending command and a descending command for the cutting unit 10 are provided. Based on the operation of the operating lever 28 to be instructed, a raising switch SW1 for instructing raising of the cutting part, a lowering switch SW2 for instructing lowering of the cutting part, and the like are provided.

  On the other hand, the control device 22 outputs drive signals for the hydraulic control electromagnetic valves 29 to 33 for hydraulic control of the cutting cylinder C1 and the four body posture changing hydraulic cylinders C2 to C5. The control device 22 operates the cutting cylinder C1 so that the value detected by the cutting height sensor 9 is maintained at the set cutting height set by the cutting height setting device 39 during the cutting operation. Perform height control.

  Based on the detection information of the front / rear inclination angle sensor 24 using the control device 22, the operation of the posture changing operation means 100 is performed so that the front / rear inclination angle with respect to the horizontal reference plane of the vehicle body V is maintained at the set inclination angle. Attitude control means 400 is configured to execute pitching control to be controlled. As the pre- and post-set inclination angles, an inclination angle 0 (zero), that is, an inclination angle corresponding to a horizontal state is set in advance. The posture control unit 400 controls the operation of the posture change operation unit 100 based on the detection information of the left / right tilt angle sensor 23 so that the left / right tilt angle with respect to the horizontal reference plane of the vehicle body V is maintained at the set tilt angle. The left / right posture control is also executed.

  Further, using the control device 22, posture variation timing determination means 200 is configured to determine whether or not the posture variation timing is predicted to greatly change the posture of the vehicle body V with respect to the traveling devices 1R and 1L.

  In other words, the control device 22 is based on the detection values of the stroke sensors 18, 19, 20, and 21 so that one end side in the front-rear direction of the vehicle body V is the most with respect to the grounding portion of the traveling devices 1R and 1L. Even though it is detected that it is in the uppermost position that is rising and the other end in the front-rear direction of the vehicle body V is in the lowermost position that is lowest with respect to the grounding portion of the traveling device. Based on the detection information of the front / rear inclination angle sensor 24, when an inclination state in which the one end side portion of the vehicle body V is inclined upward from the other end side portion is detected, it is determined that it is the posture variation timing. It is configured.

  When the posture change timing discriminating unit 200 determines that the posture change timing is not the posture change timing, the posture control unit 400 stops raising and lowering one of the front end side portion and the rear end side portion of the vehicle body V. Performing a one-side drive type attitude changing operation to operate a part of the four hydraulic cylinders C2 to C5 so as to raise and lower the other so that the inclination angle with respect to the horizontal reference plane of the vehicle body V becomes the set inclination angle; When the posture variation timing discriminating means 200 determines that it is the posture variation timing, the inclination angle of the vehicle body V with respect to the horizontal reference plane at the front end side portion and the rear end side portion at the same time becomes the set inclination angle. In order to ascend and descend as much as possible, it is configured to execute a posture change operation of a double-sided drive type in which each of the four hydraulic cylinders C2 to C5 is operated.

  Briefly describing the posture change operation of the one-side drive type, out of the four hydraulic cylinders C2 to C5, two hydraulic cylinders (left front cylinder C2 and right front cylinder C4) located at the left front part and the right front part; The other two hydraulic cylinders C2 to C5 are stopped while driving any one of the two hydraulic cylinders (left rear cylinder C3 and right rear cylinder C5) located at the left rear and right rear. Of the four hydraulic cylinders C2 to C5, the two hydraulic cylinders (the left front cylinder) positioned at the left front part and the left rear part among the four hydraulic cylinders C2 to C5. C2 and the left rear cylinder C3) and the hydraulic pressure of one of the two hydraulic cylinders (the right front cylinder C4 and the right rear cylinder C5) located at the right front and right rear. Linda (C2, C3 or C4, C5) in a state of driving stop, and is configured of the other two hydraulic cylinders (C2, C3 or C4, C5) to drive operation.

  Explaining the posture change operation of the both-side drive type, the front and rear inclination angles of the two hydraulic cylinders C2 and C4 and the other two hydraulic cylinders C3 and C5 with respect to the horizontal reference plane of the vehicle body V are set. They are operated simultaneously so that the tilt angle is set back and forth.

  When the relation with the actual work in the field is described, in the combine, the work process along each side M1 to M4 is performed in a so-called mowing form for the field M of the rectangular section as shown in FIG. There is a case of cutting and traveling, but when traveling backward, pitching control as will be described later is executed so that the front-rear posture of the aircraft becomes horizontal as shown in FIG. Despite this, the front end side portion of the vehicle body is at the uppermost position where it is most elevated with respect to the grounding portions of the traveling devices 1R and 1L, and the rear end side portion of the vehicle body V is Despite being at the lowest position where the traveling devices 1R and 1L are lowered most with respect to the ground contact portion, the forward tilt posture is detected based on the detection information of the front / rear tilt angle sensor 24 without being in a horizontal posture. It is that there is. In such a case, the posture change operation of the both-side drive type is executed.

  Next, a specific control operation of the pitching control by the control device 22 will be described based on the flowcharts of FIGS. This pitching control is executed when a threshing clutch switch (not shown) for detecting whether the threshing clutch 45 is turned on or off is turned on.

  As shown in FIG. 10, when the pitching control is started, the posture variation timing determination process is first executed, and the deviation between the detected value of the front / rear inclination angle sensor 24 and the signal value corresponding to the set front / rear inclination angle is determined as the pitching control. If it is out of the dead zone for use, it is determined from the determination result of the posture variation timing determination processing whether or not it is determined that it is the posture variation timing at that time. If the posture change timing is determined, and the posture change timing is determined, the posture change operation of the double-side drive type is executed.

Next, the posture variation timing determination process will be described.
As shown in FIG. 9, if the posture change timing is not set at that time, either the left front cylinder C2 or the right front cylinder C4 is detected based on the detection information of the left and right stroke sensors 18 and 20 located at the front of the body. One of the left rear cylinder C3 and the right rear cylinder C5 is operated to the lower limit position based on whether or not the upper limit position is operated and the detection information of the left and right stroke sensors 19 and 21 located at the rear of the machine body. Depending on whether or not the front end side portion of the vehicle body V is at the uppermost position where it is most elevated with respect to the grounding portion of the traveling devices 1R and 1L, and the rear end side portion of the vehicle body V is the position of the traveling devices 1R and 1L. It is determined whether or not it is at the lowest position where it descends most with respect to the grounding portion.

  Then, in a state where it is determined that the front end side portion of the vehicle body V is at the uppermost position and the rear end portion of the vehicle body V is at the lowermost position, the detection information of the front / rear inclination angle sensor 24 is further included. If it is determined that the front end position of the vehicle body V is a forward leaning position located above the rear end position, the posture variation timing is set assuming that the determination condition is satisfied.

  If the determination condition as described above is not satisfied, the setting of the posture variation timing is canceled. Further, while the posture change timing is set, the detected value of the front / rear tilt angle sensor 24 and the signal value corresponding to the set front / rear tilt angle are being executed while the posture change operation of the double-sided drive type as described later is executed. Is within the dead zone for pitching control or the detection result of each of the stroke sensors 18 to 21 causes the front end side portion of the vehicle body V to descend most with respect to the grounding portion of the traveling devices 1R and 1L. In the lowermost position, and the rear end portion of the vehicle body V is in the uppermost position where it is most elevated with respect to the grounding portion of the traveling devices 1R and 1L, and the operation limit of the posture correction operation is detected. If operated, the setting of posture change timing is canceled.

Next, the one-side drive type posture changing operation will be described.
As shown in FIG. 11, if the deviation between the detected value of the front / rear inclination angle sensor 24 and the set front / rear inclination angle deviates from the pitching dead zone to the front inclination side of the vehicle body V, the left and right stroke sensors 19 located at the rear of the vehicle body. , 21 based on the detected information, it is determined whether any of the left rear cylinder C3 and the right rear cylinder C5 is operated to the lower limit position, and both the cylinders C3, C5 must be operated to the lower limit position. For example, the left rear cylinder C3 and the right rear cylinder C5 are shortened until either one of the cylinders C3 and C5 reaches the lower limit position.

If one of the left rear cylinder C3 and the right rear cylinder C5 is operated to the lower limit position, then the left front cylinder C2 and the right front cylinder are next based on the detection information of the left and right stroke sensors 18 and 20 located at the front of the machine body. It is determined whether or not any of C4 is operated to the upper limit position, and if both cylinders C2 and C4 are not operated to the upper limit position, the left front cylinder C2 and the right front cylinder are maintained until either one reaches the upper limit position. Shorten C4.

  If the deviation between the detected value of the front / rear inclination angle sensor 24 and the set front / rear inclination angle deviates from the pitching dead zone to the rear inclination side of the vehicle body V, the detection information of the left and right stroke sensors 18, 20 located at the front of the vehicle body Based on the above, it is determined whether either the left front cylinder C2 or the right front cylinder C4 is operated to the lower limit position. If both the cylinders C2, C4 are not operated to the lower limit position, both the cylinders C2, The left front cylinder C2 and the right front cylinder C4 are extended until either one of C4 reaches the lower limit position.

If either the left front cylinder C2 or the right front cylinder C4 is operated to the lower limit position, then the left rear cylinder C3 and the right rear cylinder C5 are based on the detection information of the left and right stroke sensors 19, 21 located at the rear of the machine body. Are determined to be operated to the upper limit position, and if both cylinders C3 and C5 are not operated to the upper limit position, the left rear cylinder C3 and the right rear cylinder are operated until either of them reaches the upper limit position. The cylinder C5 is extended.

  As described above, when two hydraulic cylinders are simultaneously driven, if there is a difference in the change speed of the operation amount (cylinder expansion / contraction amount) by the two hydraulic cylinders to be driven, for example, the speed is slow. The operating state of the two hydraulic cylinders, such as driving the hydraulic cylinder with the higher speed intermittently while driving the hydraulic cylinder continuously, or changing and adjusting the flow rate of the hydraulic oil to be supplied By adjusting the control, the operation is controlled so that the difference in the operation amount between the two hydraulic cylinders to be driven is within the set value.

Next, the posture change operation of the both-side drive type will be described.
As shown in FIG. 12, if the deviation between the detected value of the front / rear tilt angle sensor 24 and the set front / rear tilt angle deviates from the pitching dead zone to the front tilt side of the vehicle body V, the left rear cylinder C3 and the right rear cylinder C5 If any of the cylinders C3 and C5 does not reach the lower limit position, the left rear cylinder C3 and the right rear cylinder C5 are shortened until either one of the cylinders C3 and C5 reaches the lower limit position, and the left front cylinder C2 and the right front cylinder C4 If one of the cylinders C2 and C4 has not reached the upper limit position, the left front cylinder C2 and the right front cylinder C4 are shortened until either one of the cylinders C2 and C4 is operated to the upper limit position.

  If the deviation between the detected value of the front / rear tilt angle sensor 24 and the set front / rear tilt angle deviates from the pitching dead zone to the rear tilt side of the vehicle body V, either the left front cylinder C2 or the right front cylinder C4 is operated to the lower limit position. If not, the left front cylinder C2 and the right front cylinder C4 are extended until either one of the cylinders C2 and C4 reaches the lower limit position, and either the left rear cylinder C3 or the right rear cylinder C5 is operated to the upper limit position. If not, the left rear cylinder C3 and the right rear cylinder C5 are extended until either one of the cylinders C3 and C5 reaches the upper limit position.

That is, in this posture change operation of the both-side drive type, the hydraulic cylinders (C2, C4) acting on one end side in the front-rear direction and the hydraulic cylinders (C3, C5) acting on the other end side in the front-rear direction are changed. The vehicle body V is operated simultaneously so that the front / rear inclination angle with respect to the horizontal reference plane of the vehicle body V becomes the set front / rear inclination angle. Although not described in detail, the operation speed may be different if the loads applied to the plurality of hydraulic cylinders C2 to C5 are different. For example, the hydraulic oil supplied based on the amount of expansion / contraction operation per unit time of each hydraulic cylinder The operation state of the plurality of hydraulic cylinders is adjusted by changing and adjusting the flow rate.

[Second Embodiment]
Next, a second embodiment will be described. In this embodiment, the configuration of the posture variation timing discriminating means 200 is different from that of the first embodiment, but the other configurations are the same as those of the first embodiment, so only the different configurations will be described, and the same configurations will be described. Is omitted.

  That is, in this embodiment, it is detected that the posture variation timing determination means 200 has changed from a state in which the vehicle body travels forward to a state in which the vehicle body travels backward within a set time, or the vehicle body travels backward. When it is detected that the vehicle has changed from the present state to the forward traveling state within the set time, the posture variation timing is determined. In other words, the control device 22 determines whether or not the vehicle body has changed from a state of traveling forward to a state of traveling backward within a set time based on detection information of the shift lever sensor 52, or It is configured to determine whether or not it has changed from a state of traveling backward to a state of traveling forward within a set time, and from the determination result, it is determined whether or not it is the posture variation timing.

Next, posture variation timing determination processing by the control device 22 will be described based on the flowchart of FIG.
Based on the detection information of the shift lever sensor 52, it is detected that the vehicle has switched to a state where the vehicle travels backward within a set time for determination (for example, several seconds) after the forward traveling is stopped, or the backward traveling is stopped. Then, when it is detected that the vehicle has switched to the state of traveling forward within the set time for determination, the posture variation timing is set assuming that the determination condition is satisfied.

  Even if the above-mentioned determination conditions are not satisfied, if it is determined that it is posture change timing and the set time for continuation has not elapsed, the determination conditions are still satisfied. Although it is determined that it is the posture change timing, when the set time for continuation has passed, the setting of the posture change timing is canceled. The set time for continuation is a time set in advance as a need to continuously execute the posture change operation of the double-side drive type.

[Third Embodiment]
Next, a third embodiment will be described. In this embodiment, the configuration of the attitude variation timing discriminating means 200 and the content of the control by the attitude control means 400 are different from those of the first embodiment, but other configurations are the same as those of the first embodiment, Only the description is omitted, and the description of the same configuration is omitted.

  That is, in this embodiment, when performing the rolling control as the posture change control, if it is determined by the posture variation timing determining means 200 that the posture variation timing is not the one end side in the left and right direction of the vehicle body V and One of the other end portions is lifted and stopped, and a part of the plurality of driving means is operated to raise and lower the other so that the left / right inclination angle with respect to the horizontal reference plane of the vehicle body V becomes the set left / right inclination angle. When the posture change operation of the one-side drive type is executed and it is determined by the posture change timing determining means 200 that the posture change timing, the one end side position and the other end side position of the vehicle body V in the left-right direction are determined. At the same time, both sides for operating each of the plurality of drive means so as to move up and down so that the left / right inclination angle with respect to the horizontal reference plane of the vehicle body V becomes the set left / right inclination angle. It is configured to perform the attitude change operation of the dynamic type.

  Specifically, if the driving speed of the traveling device is greater than or equal to a set value based on the detection information of the vehicle speed sensor 50 serving as the traveling speed detecting unit, the attitude variation timing determining unit 200 is configured to perform the attitude variation timing. It is configured to determine that there is.

Next, a specific control operation of the rolling control by the control device 22 will be described based on the flowcharts of FIGS.
As shown in FIG. 16, when the deviation between the detected value of the left / right tilt angle sensor 23 and the signal value corresponding to the set left / right tilt angle is out of the dead zone for rolling control, the discrimination processing of the posture variation timing discriminating means 200 is performed. The vehicle speed detected by the vehicle speed sensor 50, that is, whether or not the driving speed of the traveling devices 1R and 1L is equal to or higher than a set value is used to determine whether or not it is the posture variation timing. For example, a one-side drive type posture change operation is executed, and if it is determined that the posture change timing, a double-side drive type posture change operation is executed.

Next, the one-side drive type posture changing operation will be described.
As shown in FIG. 17, if the deviation between the detected value of the left / right tilt angle sensor 23 and the set left / right tilt angle is outside the dead zone of the rolling control to the left tilt side of the vehicle body V, the front and rear stroke sensors located on the right side of the body Based on the detection information of 20, 21, it is determined whether either the right front cylinder 4 or the right rear cylinder C5 is operated to the lower limit position, and both the cylinders C4, C5 must be operated to the lower limit position. For example, the right front cylinder 4 is extended and the right rear cylinder C5 is shortened until one of them reaches the lower limit position.

If either the right front cylinder 4 or the right rear cylinder C5 is operated to the lower limit position, then the left front cylinder C2 and the left rear cylinder C3 are based on the detection information of the front and rear stroke sensors 18, 19 located on the left side of the machine body. Is determined to be operated to the upper limit position. If neither of the cylinders C2 and C3 is operated to the lower limit position, the left front cylinder C2 is shortened until one of the cylinders reaches the upper limit position. The left rear cylinder C3 is extended.

  If the deviation between the detected value of the left / right tilt angle sensor 24 and the set left / right tilt angle deviates from the dead zone of the rolling control to the right tilt side of the vehicle body V, the detection information of the front and rear stroke sensors 18, 20 located on the left side of the body Based on the above, it is determined whether any of the left front cylinder C2 or the left rear cylinder C3 is operated to the lower limit position, and if both the cylinders C2 and C3 are not operated to the lower limit position, Until the position is reached, the left front cylinder C2 is extended and the left rear cylinder C3 is shortened.

If either the left front cylinder C2 or the left rear cylinder C3 is operated to the lower limit position, then the right front cylinder C4 and the right rear cylinder C5 are based on the detection information of the front and rear stroke sensors 19, 21 located on the right side of the machine body. Is determined to be operated to the upper limit position, and if both cylinders C4 and C5 are not operated to the upper limit position, the right front cylinder C4 is shortened until one reaches the upper limit position. Further, the right rear cylinder C5 is extended.

Next, the posture change operation of the both-side drive type will be described.
As shown in FIG. 18, if the deviation between the detected value of the left / right tilt angle sensor 23 and the set left tilt angle deviates from the dead zone for rolling control to the left tilt side of the vehicle body V, the front and rear strokes positioned on the right side of the body Based on the detection information of the sensors 20, 21, it is determined whether either the right front cylinder 4 or the right rear cylinder C5 is operated to the lower limit position, and both the cylinders C4, C5 are operated to the lower limit position. Otherwise, until either reaches the lower limit position, the right front cylinder 4 is extended and the right rear cylinder C5 is shortened, and further, based on the detection information of the front and rear stroke sensors 18 and 19 located on the left side of the machine body, It is determined whether either the left front cylinder C2 or the left rear cylinder C3 is operated to the upper limit position, and both the cylinders C2 and C3 are operated to the lower limit position. Kere words, until one reaches the upper limit position, is extended actuating the and left rear cylinder C3 is shortened operating the left front cylinder C2.

  If the deviation between the detected value of the left / right tilt angle sensor 23 and the set left tilt angle deviates from the dead zone for rolling control to the right tilt side of the vehicle body V, the detection information of the front and rear stroke sensors 18, 19 located on the left side of the body Based on the above, it is determined whether any of the left front cylinder C2 or the left rear cylinder C3 is operated to the lower limit position, and if both the cylinders C2 and C3 are not operated to the lower limit position, Until the position is reached, the left front cylinder 2 is extended and the left rear cylinder C3 is shortened. Further, based on the detection information of the front and rear stroke sensors 20 and 21 located on the right side of the body, the right front cylinder 4 and the right rear cylinder It is determined whether or not any of C5 is operated to the upper limit position, and if both cylinders C4 and C5 are not operated to the upper limit position, Until it reaches the limit position, and to extend operating the right rear cylinder C5 is shortened operate the right front cylinder 4.

[Another embodiment]
Hereinafter, other embodiments are listed.

(1) In the third embodiment, when rolling control is executed as the posture change control, it is configured to determine that it is the posture variation timing if the driving speed of the traveling device is equal to or higher than a set value. In the case where the pitching control is executed as the posture change control, it may be determined that it is the posture variation timing if the driving speed of the traveling device is equal to or higher than a set value.

(2) In each of the above embodiments, the traveling device is constituted by a pair of left and right crawler type traveling devices, but is not limited to this. For example, a single traveling device may be used, and not a crawler type. A wheel-type traveling device may be used.

(3) In each of the above embodiments, the posture changing operation means 100 is configured by the four hydraulic cylinders C2 to C5 positioned at the four front, rear, left and right positions of the machine body V, but in addition to the hydraulic cylinders, You may comprise by the other drive means which consists of a screw feed mechanism etc. Further, as a configuration for changing only the front-rear inclination angle in the vehicle body, a configuration in which one end side portion and the other end side portion separated in the vehicle body front-rear direction are moved up and down by a single hydraulic cylinder with respect to the grounding portion of the traveling device. As a configuration for changing only the right and left inclination angle in the vehicle body, one end side portion and the other end side portion separated in the right and left inclination angle changing direction are respectively connected to one hydraulic cylinder with respect to the grounding portion of the traveling device. It is good also as a structure which raises / lowers.

(4) In the above embodiment, the combine is exemplified as the work vehicle. However, for example, a work vehicle other than the combine such as an agricultural tractor or a rice planting machine may be used.

Side view showing the front of the combine Side view showing the lifting / lowering configuration of the traveling device Side view showing the lifting / lowering configuration of the traveling device Side view showing the lifting / lowering configuration of the traveling device Side view showing the lifting / lowering configuration of the traveling device Power transmission diagram The perspective view which shows the structure of an inclination angle detection means. Block diagram showing control configuration Flow chart showing control operation Flow chart showing control operation Flow chart showing control operation Flow chart showing control operation The figure which shows the change of the front and back inclination posture The top view which shows the work state in the circumference cutting form in the field Flow chart showing control operation Flow chart showing control operation Flow chart showing control operation Flow chart showing control operation

Explanation of symbols

1R, 1L Traveling devices 23, 24 Inclination angle detection means 50 Travel speed detection means 100 Attitude change operation means 200 Attitude change timing determination means 400 Attitude control means C2, C3, C4, C5 Driving means V Car body

Claims (5)

A posture change operation means that can freely change the posture of the vehicle body with respect to the traveling device, a posture control means that controls the operation of the posture change operation means, and an inclination angle detection means that detects an inclination angle of the vehicle body with respect to a horizontal reference plane. Configured
The posture changing operation means is configured to include a plurality of driving means capable of moving up and down with respect to the grounding part of the traveling device at one end side position and the other end side position apart in the inclination angle changing direction in the vehicle body,
Based on the detection information of the inclination angle detection means, the attitude control means controls the operation of the attitude change operation means so that the inclination angle with respect to the horizontal reference plane of the vehicle body is maintained at the set inclination angle. A work vehicle attitude control device configured to perform,
Posture variation timing determination means for determining whether or not the posture variation timing is predicted to greatly change the posture of the vehicle body with respect to the traveling device;
In the posture change control, the posture control means
When the posture variation timing determining means determines that it is not the posture variation timing, one of the one end side portion and the other end side portion of the vehicle body is lifted and stopped, and the other one with respect to the horizontal reference plane of the vehicle body Performing a one-sided drive type posture changing operation for operating a part of the plurality of driving means so as to move up and down so that the inclination angle becomes a set inclination angle; and
When the posture variation timing determining means determines that it is the posture variation timing, the inclination angle with respect to the horizontal reference plane of the vehicle body simultaneously becomes the set inclination angle at the one end side portion and the other end side portion of the vehicle body. An attitude control device for a work vehicle configured to execute an attitude change operation of a double-sided drive type that operates each of the plurality of driving means to move up and down. The posture change operation means is configured to change and operate a front / rear inclination angle with respect to a horizontal reference plane of the vehicle body,
The tilt angle detecting means is configured to detect a front / rear tilt angle with respect to a horizontal reference plane of the vehicle body;
The posture control means controls the posture change operation means as the posture change control so that the front / rear inclination angle with respect to the horizontal reference plane of the vehicle body is set to the set front / rear inclination angle based on the detection information of the inclination angle detection means. 2. The attitude control device for a work vehicle according to claim 1, which is configured as described above. The posture variation timing discriminating means is
The one end side portion of the vehicle body is at the uppermost position where it is most elevated with respect to the grounding portion of the traveling device, and the other end side portion of the vehicle body is most lowered with respect to the grounding portion of the traveling device. In spite of being in the lowest position, when the tilt state in which the one end side position in the vehicle body is located below the other end side position is detected based on the detection information of the tilt angle detecting means, The work vehicle posture control apparatus according to claim 2, wherein the work vehicle posture control device is configured to determine that it is a posture change timing. The posture variation timing discriminating means is
It has been detected that the vehicle has changed from a state where the vehicle is traveling forward to a state where the vehicle is traveling backward within a set time, or has been changed from a state where the vehicle body is traveled backward to a state where the vehicle is traveling forward within the set time. The work vehicle attitude control device according to claim 2, wherein when detected, the attitude control timing is determined to be the attitude change timing. The posture changing operation means is configured to change and operate a left / right inclination angle with respect to a horizontal reference plane of the vehicle body,
The tilt angle detecting means is configured to detect a left / right tilt angle with respect to a horizontal reference plane of the vehicle body;
The posture control means controls the posture change operation means as the posture change control based on the detection information of the left / right inclination angle detection means so that the left / right inclination angle with respect to the horizontal reference plane of the vehicle body becomes a set left / right inclination angle. Configured as
Travel speed detection means for detecting the drive speed of the travel device is provided,
If the driving speed of the traveling device detected by the traveling speed detecting means is greater than or equal to a set value based on the detection information of the traveling speed detecting means, the attitude variation timing determining means is the attitude variation timing. The work vehicle attitude control device according to claim 1, which is configured to discriminate between

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