JP5134557B2 - Combine traveling control device - Google Patents

Description

  The present invention relates to a combine traveling control device configured to transmit engine power to a reaping processing unit, a threshing device, and a hydrostatic continuously variable transmission for traveling.

  As a conventional example of a combined travel control device configured to transmit engine power to a mowing processing unit, a threshing device, and a hydrostatic continuously variable transmission for traveling, a hydrostatic continuously variable transmission of The variable displacement hydraulic pump is configured to be shifted by a shift lever, and further includes an electric motor that operates the shift lever, a rotation speed detection sensor that detects the rotation speed of the engine, and a control that controls the operation of the electric motor. When the control device determines that the engine load has increased due to a decrease in the rotational speed of the engine, there is a device configured to operate the shift lever to the low speed side by an electric motor (for example, Patent Documents). 1).

JP-A-6-159487

The conventional combine travel control device reduces the engine load by reducing the travel speed when the engine load increases, but has the following disadvantages.
That is, the conventional combine travel control device reduces the engine load by reducing the travel speed after the engine load increases and the engine speed decreases, and the engine speed decreases. Since the driving speed of the threshing device also decreases, there is a possibility that the threshing device cannot be continuously driven at an appropriate driving speed.
In addition, operating the variable displacement hydraulic pump of the hydrostatic continuously variable transmission to the low speed side reduces the discharge rate of the hydraulic pump of the hydrostatic continuously variable transmission, so the traveling speed of the aircraft is low. At the same time, the driving force (torque) for traveling also decreases, and when the hydraulic pump of the hydrostatic continuously variable transmission is operated to the low speed side, the driving force (torque) for traveling becomes insufficient. In particular, there is a possibility that the inconvenience becomes remarkable in turning at a headland.

  In other words, as the traveling mode of the combine V when performing the cutting processing work, the traveling mode shown in FIG. 13 is often used. In other words, the rotational cutting traveling mode travels one work process in a straight traveling state or a state close to it while cutting the grain husk group W in the field, and travels from the location where the husk group W exists to the headland Z, Then, after traveling to the headland Z, it turns to change the direction by 90 degrees toward the side where the next work process is located, and after the turn, the headland is moved toward the location where the next work process exists. Drive straight or close to it and turn at a position corresponding to the next work stroke so that the direction changes 90 degrees toward the beginning of the next work stroke. This is a mode in which the vehicle travels in a straight line state or a state close to it toward the starting end side, and such a rotational mowing travel mode is generally used when performing a cutting processing operation.

  When performing the cutting process work in such a state of cutting cutting, there is no load for driving the cutting process unit immediately after the harvesting process in which the combine travels from the location where the grain pods exist to the headland, but the threshing device The load that drives the vehicle and the traveling load act on the engine. And immediately after the mowing process, since a large amount of processed material remains in the threshing apparatus, the load for driving the threshing apparatus is a large load. In addition, the traveling load becomes a load larger than that in the straight traveling state at the time of turning.

  For this reason, as described above, when the combine travels from the location where the cereal group exists to the headland and turns toward the side where the next work process is located in the headland, a large load that drives the threshing device, A large traveling load for turning acts on the engine, which may cause a state where the rotational speed of the engine is significantly reduced. And if the rotational speed of an engine falls significantly, the drive speed of a threshing device will fall significantly from an appropriate drive speed, and the inconvenience which cannot perform a handling process and a selection process favorably will be caused.

  Further, the turn at the headland is a sudden turn so as to change the direction by 90 degrees, and it is desirable to obtain a large driving force (torque) for traveling. Since the discharge amount of the hydraulic pump of the hydraulic continuously variable transmission is reduced and the driving force (torque) for traveling is also reduced, there is a possibility that the sudden turning at the headland may not be appropriately performed.

  The present invention has been made in view of the above circumstances, and its purpose is to properly drive the threshing device even during turning at the headland and to drive the turning at the headland. The object of the present invention is to provide a combine traveling control device that can appropriately perform in a state where a shortage of force (torque) is avoided.

The present invention relates to a combine traveling control device configured to transmit engine power to a reaping processing unit, a threshing device, and a hydrostatic continuously variable transmission for traveling. Is
Holding means for holding the operation part for changing the capacity of the variable capacity hydraulic motor of the hydrostatic continuously variable transmission device from the set target position to the low speed side with an operating force for moving the high speed side;
Operating force adjusting means for changing and adjusting the operating force of the holding means;
Position detecting means for detecting the position of the operation unit;
A cutting work state detecting means for detecting whether or not a cutting work state;
Control means for executing an operation force adjustment process for controlling the operation of the operation force adjustment means so as to maintain the operation unit at a set target position based on detection information of the position detection means is provided,
After the control means detects that the cutting work state detection means has switched from the cutting work state to the non-cutting work state, the operation unit controls the set target as the operation force adjustment process. The operation immediately after the cutting process that controls the operation of the operating force adjusting means in a form that does not increase the operating force of the holding means exceeding the set upper limit value immediately after the cutting process even when moving to a lower speed side than the position. The force adjustment processing is configured to be executed.

In other words, the operation unit for changing the capacity of the variable displacement hydraulic motor in the hydrostatic continuously variable transmission device tries to move from the set target position to the low speed side due to the traveling load, but the holding means is set by the operation unit. The movement from the target position to the low speed side is held by the operating force for moving the high speed side.
Then, based on the detection information of the position detecting means for detecting the position of the operating section, the control means operates the operating force adjusting means to change and adjust the operating force of the holding means so as to maintain the operating section at the set target position. With this control, the operation unit is maintained at the set target position even when the traveling load increases or decreases.
In addition, after the control means detects that the cutting work state detection means has switched from the cutting work state to the non-cutting work state, the operation unit may move to a lower speed side than the set target position. Because the operation of the operating force adjusting means is controlled in a form that does not increase the operating force of the holding means beyond the set upper limit value immediately after the cutting process, the traveling load increases due to turning in the headland and is held. When the operating force of the means is increased to the set upper limit value and the travel load further increases, the operating part moves to the low speed side, and the rotational speed of the variable displacement hydraulic motor sets the operating part. The engine speed is reduced by operating the motor at a lower speed than the rotational speed at the time of positioning at the target position.

  In this way, when the traveling load increases, the control means operates the hydraulic motor of the hydrostatic continuously variable transmission to the low speed side even when the control unit moves to the low speed side from the set target position. Since the operation force adjustment means is controlled in such a way that the operation force of the holding means is not increased beyond the set upper limit value, the engine speed decreases even if the driving load increases due to turning. Before or significantly lowering the operating load, operate the rotational speed of the hydraulic motor of the hydrostatic continuously variable transmission to a lower speed than the rotational speed when the operating unit is positioned at the set target position. Thus, the engine speed can be suppressed from decreasing due to the traveling load.

Furthermore, when the driving load increases, the control means operates the hydraulic motor of the hydrostatic continuously variable transmission to the low speed side, even if the control means moves to the low speed side from the set target position. Since it is performed by controlling the operation of the operating force adjusting means in a form that does not increase the operating force of the holding means beyond the upper limit value, even if the driving load suddenly increases, a large load is not applied to the engine It is possible to perform accurately.
That is, when the traveling load increases, as a configuration for operating the hydraulic motor of the hydrostatic continuously variable transmission to the low speed side, for example, based on the detection information of the torque detection means that detects the driving torque of the hydraulic motor, Although it is conceivable to operate an actuator that operates the operation unit to the low speed side, a response delay occurs when the drive torque is detected to activate the actuator.
On the other hand, according to the first characteristic configuration, the control means does not increase the operating force of the holding means beyond the set upper limit value even if the operation unit moves to a lower speed side than the set target position. By controlling the operation of the operating force adjustment means, when the driving load increases, there is no special operation and the rotational speed of the variable displacement hydraulic motor is reduced, so there is a response delay. When the running load increases without causing any problems, the hydraulic motor of the hydrostatic continuously variable transmission can be accurately operated to the low speed side, and the running load increases rapidly due to turning. Sometimes, it is possible to control the rotational speed of the hydraulic motor to the low speed side without delay in response so that a large load is not applied to the engine.

  In addition, operating the rotational speed of the hydraulic motor of the hydrostatic continuously variable transmission to a lower speed than the rotational speed when the operating unit is positioned at the set target position is a variable capacity in the hydrostatic continuously variable transmission. The hydraulic motor of the hydrostatic continuously variable transmission is not much, even if sufficient hydraulic oil is supplied from the hydraulic pump of the hydrostatic continuously variable transmission to the hydraulic motor. It does not have to rotate. As a result, when the hydraulic motor of the hydrostatic continuously variable transmission is operated to the low speed side, if the discharge amount of the hydraulic pump of the hydrostatic continuously variable transmission is secured, the hydrostatic continuously variable transmission of Low-speed power having a sufficient driving force (torque) for traveling is transmitted from the hydraulic motor to the lower transmission side.

As described above, when the running load increases, the hydraulic motor of the hydrostatic continuously variable transmission is operated to the low speed side, thereby reducing the load acting on the engine and suppressing the engine speed from decreasing. Moreover, since it is possible to transmit low-speed power with sufficient driving force (torque) for traveling to the traveling device, the combine travels from the location where the cereals are present to the headland, When turning toward the side where the next work process is located in the headland, it is possible to suppress a decrease in the rotational speed of the engine, and that the driving force (torque) for running for turning is insufficient. It can be avoided.
And since it can suppress that the rotational speed of an engine falls also at the time of turning, a threshing apparatus can be continuously driven with a suitable drive speed.

  Therefore, according to the first characteristic configuration of the present invention, the threshing device is properly driven even when turning on the headland, and the turning on the headland avoids a shortage of driving force (torque) for traveling. It is possible to provide a combine travel control device that can be appropriately performed in a state in which the vehicle is in a state of being connected.

In addition to the first feature configuration, the second feature configuration of the present invention includes:
A turning state detecting means for detecting whether or not the turning state is provided;
After the control means detects that the cutting work state detection means has switched from the cutting work state to the non-reaching work state, and the turning state detection means is in a turning state. When it is detected, an operation force adjustment process immediately after the cutting process is executed, and it is detected by the cutting work state detection means that the cutting work state is switched to the non-cutting work state. However, when it is not detected that the turning state is detected by the turning state detection means, the operation force adjustment process increases the operation force of the holding means beyond the set upper limit immediately after the cutting process. The operation force adjusting process for normal traveling for controlling the operation of the operation force adjusting means is executed.

That is, after the control means detects that the cutting work state detection means switches from the cutting work state to the non-reaching work state, the turning state detection means detects that the turning state is in the turning state. When the operation unit is moved, the operation of the operation force adjusting unit is controlled in such a manner that the operation force of the holding unit does not increase beyond the set upper limit value immediately after the cutting process even if the operation unit moves to a lower speed side than the set target position. The operating force adjustment process immediately after the cutting process is executed.
Even if the control means detects that the cutting work state detection means has switched from the cutting work state to the non-reaching work state, the turning state detection means may be in the turning state. If not detected, the normal driving operating force adjustment process for controlling the operation of the operating force adjusting means is executed in such a manner that the operating force of the holding means is increased beyond the set upper limit value immediately after the cutting process.

  Thus, even if it is detected by the cutting operation state detection means that the cutting operation state is switched to the non-cutting operation state, the turning state detection means does not detect that the vehicle is in the turning state. In some cases, an operation force adjustment process for normal travel is performed to control the operation of the operation force adjustment means in a form that increases the operation force of the holding means beyond the set upper limit value immediately after the cutting process. If a large traveling load occurs and the engine is not in a state where a large load is applied to the engine, do not unnecessarily perform the operating force adjustment process immediately after the cutting process, and the traveling speed will be unnecessarily low. It becomes what can suppress becoming.

  Therefore, according to the 2nd characteristic composition, in addition to the operation effect by the 1st characteristic composition, the traveling control device of the combine which can control that traveling speed becomes low unnecessarily can be provided.

The third feature configuration of the present invention is in addition to the second feature configuration,
After the control means detects that the cutting work state has been switched from the cutting work state to the non-cutting work state, the set time has elapsed since the switching was detected. Until the turning state detecting means detects that the turning state is in the turning state, the operating force adjustment process immediately after the cutting process is executed, and the cutting work state detecting means performs the cutting work. Even when it is detected that the state has been switched to the non-reaping work state, the turning state detecting means does not detect the turning until the set time elapses after the switching is detected. When it is not detected that the vehicle is in a turning state, the operation force adjustment unit is controlled to increase the operation force of the holding unit exceeding the set upper limit value immediately after the cutting process as the operation force adjustment process. For normal driving In that it is configured to perform an operation force adjustment process.

That is, after the control means detects that the cutting work state detection means has switched from the cutting work state to the non-cutting work state, the set time has elapsed since the switching was detected. If the turning state detection means detects that the turning state is in the meantime until the elapsed time, even if the operation unit moves to a lower speed side than the set target position, the set upper limit value immediately after the cutting process is exceeded. Thus, the operation force adjustment process immediately after the cutting process for controlling the operation of the operation force adjustment means in a form that does not increase the operation force of the holding means is executed.
Even after the control means detects that the cutting work state detection means has switched from the cutting work state to the non-reaching work state, the set time after the switching is detected is detected. When the turning state detecting means does not detect that the turning state is detected until the time elapses, the operating force adjusting means is configured to increase the operating force of the holding means beyond the set upper limit value immediately after the cutting process. The normal driving operation force adjustment process for controlling the operation is executed.

Thus, even after the cutting operation state detecting means detects that the cutting operation state has been switched to the non-cutting operation state, the set time has elapsed since the switching was detected. Until the turning state detecting means does not detect that the turning state is detected, the operation force adjusting means is operated in such a manner that the operating force of the holding means is increased beyond the set upper limit value immediately after the cutting process. Since the operating force adjustment process for normal driving to be controlled is performed, if a large traveling load does not occur even if a large traveling load occurs due to turning, it is unnecessarily immediately after the cutting process Therefore, it is possible to suppress the traveling speed from becoming unnecessarily low by not performing the operation force adjustment process for the purpose.
In other words, if the time necessary for processing the processed material remaining in the threshing apparatus is set as the set time, the cutting operation state detection means switches the cutting operation state to the non-cutting operation state. When the set time has passed since the detection of the slag, the load that drives the threshing device becomes small, so even if a large running load occurs due to turning, a state where a large load acts on the engine does not occur In such a case, the operation force adjustment process immediately after the cutting process is not executed unnecessarily, so that the traveling speed can be suppressed from becoming unnecessarily low.

  Therefore, according to the third characteristic configuration, in addition to the operational effects of the second characteristic configuration, it is possible to provide a combined travel control device that can more appropriately suppress the traveling speed from becoming unnecessarily low.

In addition to the first feature configuration described above, the fourth feature configuration of the present invention includes:
A turning state detecting means for detecting whether or not the turning state, and an engine load detecting means for detecting an engine load acting on the engine are provided;
After the control means detects that the cutting work state detection means has switched from the cutting work state to the non-reaching work state, and the turning state detection means is in a turning state. When it is detected that the engine load detected by the engine load detection means is greater than or equal to a set amount, an operating force adjustment process immediately after the cutting process is executed, and the cutting work state detection means Even if it is detected that the cutting operation state is switched to the non-cutting operation state, the turning state detection means does not detect that the turning state is detected, or the engine load detection means When it is not detected that the engine load is greater than or equal to the set amount, the operating force adjusting means is operated in such a manner that the operating force of the holding means is increased beyond the set upper limit value immediately after the cutting process. Controlling the in that it is configured to perform an operation force adjustment processing for normal running.

That is, after the control means detects that the cutting work state detection means switches from the cutting work state to the non-reaching work state, the turning state detection means detects that the turning state is in the turning state. When it is detected that the engine load detected by the engine load detecting means is equal to or greater than the set amount, the set upper limit value immediately after the cutting process is set even if the operation unit moves to a lower speed side than the set target position. The operation force adjustment process immediately after the cutting process for controlling the operation of the operation force adjustment means in a form that does not increase the operation force of the holding means beyond is executed.
Then, even after the control means detects that the cutting work state detection means has switched from the cutting work state to the non-reaching work state, the turning state detection means detects that the turning state is present. When the engine load detection means does not detect that the engine load is greater than or equal to the set amount, the operation force adjusting means is operated in a form that increases the operation force of the holding means beyond the set upper limit value immediately after the cutting process. The normal driving operating force adjustment process for controlling the vehicle is executed.

  By the way, when the engine load detection means detects that the engine load is equal to or greater than the set amount, a large amount of processed material remains in the threshing device, and the load that drives the threshing device is large. Therefore, when the load of the engine on which the driving load and the traveling load of the threshing device are greater than the set amount, and conversely, when the engine load is less than the set amount by the engine load detecting means In the threshing device, only a small amount of the processed product remains or no processed product exists, and the load for driving the threshing device is a small load, so that the driving load and the running load of the threshing device act on the engine. Is when the load becomes less than the set amount.

  Thus, even when it is detected by the harvesting state detection means that the cutting state has been switched to the non-reaching state, the turning state detection unit does not detect that the turning state is detected. Alternatively, when the engine load detecting means does not detect that the engine load is greater than or equal to the set amount, the operation force adjusting means is controlled to increase the operating force of the holding means exceeding the set upper limit value immediately after the cutting process. Therefore, when a state in which a large traveling load is generated due to turning does not occur or when the driving load of the threshing device is small, a large load acts on the engine. In the case where there is not, it is possible to prevent the traveling speed from becoming unnecessarily low by not performing the operation force adjustment process immediately after the cutting process unnecessarily.

  Therefore, according to the 4th characteristic composition, in addition to the operation effect by the 1st characteristic composition, the traveling control device of the combine which can control that traveling speed becomes low unnecessarily can be provided.

In addition to any of the second to fourth feature configurations described above, the fifth feature configuration of the present invention includes:
When the control means is executing the operation force adjustment process immediately after the cutting process, it is detected by the cutting work state detection means that the cutting work state is switched from the non-cutting work state. Thereafter, the operation force adjustment process for normal traveling is executed.

In other words, when the control means is executing the operation force adjustment process immediately after the cutting process, it is detected by the cutting work state detection means that the non-cutting work state is switched to the cutting work state. Assuming that the traveling on the headland is completed and the cutting operation is started, the operation force adjustment processing for normal traveling is executed.
As described above, when the cutting operation is started, the operation force adjustment process for the normal traveling is executed, so that it is possible to suppress the traveling speed from being unnecessarily low during the cutting operation.

  Therefore, according to the fifth feature configuration, in addition to the operational effects of any of the second to fourth feature configurations, the traveling control of the combine that can suppress the traveling speed from becoming unnecessarily low during the cutting operation. Equipment can be provided.

In addition to any of the second to fourth feature configurations described above, the sixth feature configuration of the present invention includes:
When the control means is executing the operation force adjustment process immediately after the cutting process, it is detected by the cutting work state detection means that the non-cutting work state is switched to the cutting work state. Or when the turning state detecting means detects that the turning state is switched to the non-turning state, the operation force adjustment process for the normal traveling is executed thereafter. In the point.

  In other words, when the control means is executing the operation force adjustment process immediately after the cutting process, it is detected by the cutting work state detection means that the non-cutting work state is switched to the cutting work state. When traveling on the headland is finished and the cutting operation is started, the operating force adjustment process for normal traveling is executed, and in addition, the operating force adjustment process for immediately after the cutting process is executed When the turning state detecting means detects that the turning state is switched to the non-turning state, a large traveling load is applied for turning while driving the threshing device in which the processed material remains. Assuming that the generated state has disappeared, the normal driving operating force adjustment process is executed.

  In this way, while driving the threshing device in which the processed material remains during driving on the headland, the operation force adjustment processing for normal traveling is executed when there is no longer a state where a large traveling load is generated due to turning. Therefore, the subsequent headland can be run in a state in which the traveling speed is suppressed from becoming unnecessarily low, and the work process that has been completed is close to the next work process, etc. Even if the vehicle moves to the next work process while turning, the operating force adjustment process for normal travel is executed when the mowing work is started. It becomes possible to accurately suppress an unnecessarily low speed.

  Therefore, according to the sixth feature configuration, in addition to the operational effects of any of the second to fourth feature configurations, it is possible to travel in a state in which the traveling speed is suppressed from being unnecessarily low during the cutting operation. In addition, while driving on the headland, if the state where a large travel load is generated due to turning while driving the threshing device in which the processed material remains is left, the headland travels at a lower speed. A traveling control device for a combine that can be performed in a state in which a low speed is suppressed as necessary can be provided.

In addition to any of the second to sixth feature configurations described above, the seventh feature configuration of the present invention includes:
The engine load detected by the engine load detecting means for detecting the engine load acting on the engine when the control means is executing the operation force adjustment process immediately after the cutting process is the cutting process. When the set amount is decreased from the maximum load previously detected during the execution of the operation force adjustment process for the immediately following operation, the operation force adjustment process for the normal traveling is thereafter executed.

That is, when the control means is executing the operation force adjustment process immediately after the cutting process, the engine load detected by the engine load detecting means is being executed during the operation force adjustment process immediately after the cutting process. When the set amount is decreased from the previously detected maximum load, the operation force adjustment process for normal traveling is executed afterwards assuming that there is no state in which a large load acts on the engine.
That is, during the execution of the operating force adjustment process immediately after the cutting process, the maximum load of the engine load detected by the engine load detecting means is large for turning while driving the threshing device where the processed material remains. This is the engine load that is detected when a load is generated. When the engine load decreases by a set amount from this maximum load, the amount of processed material remaining in the threshing device decreases and the load that drives the threshing device decreases. Or when the turn is nearing the end of the turn and the driving load has decreased, and when such a condition is detected, By performing the operation force adjustment process for traveling, the operation force adjustment process for normal traveling can be executed at the earliest possible time when traveling on a headland. Traveling speed becomes capable of performing running for headland while minimizing that slower unnecessarily.

  Therefore, according to the seventh feature configuration, in addition to the operational effects of any of the second to sixth feature configurations, the operation force adjustment process for normal travel is executed as early as possible when traveling on the headland. Thus, it is possible to provide a combined travel control device that can travel the headland while suppressing the travel speed from being unnecessarily low.

In addition to any of the second to seventh feature configurations described above, the eighth feature configuration of the present invention includes:
As the set target position, a plurality of set target positions that are different positions are determined,
Selection means for selecting any of the plurality of set target positions is provided,
As the operation force adjustment process, the control unit operates the operation force adjustment unit so as to maintain the operation unit at the set target position selected by the selection unit among the plurality of set target positions. It is the point which is comprised so that the process to control may be performed.

That is, the control means controls the operation of the operating force adjusting means so as to maintain the operating portion at the set target position selected by the selecting means among the plurality of set target positions.
Since the rotation speed of the hydraulic motor can be changed to high or low by maintaining the operation unit at a plurality of different set target positions, the running speed can be changed depending on running conditions such as the hardness of the ground. In addition, if a set target position on the low speed side is selected, a large driving force (torque) for traveling can be obtained.

  Therefore, according to the eighth feature configuration, in addition to the operational effects of any of the first to sixth feature configurations, a combined travel control device capable of selecting a travel speed according to the travel conditions such as the hardness of the ground is provided. it can.

The ninth feature configuration of the present invention is in addition to the eighth feature configuration,
Even if the operation unit moves to a lower speed side than the set target position, the control means is set to a value larger than the set upper limit value immediately after the cutting process as the operation force adjustment process for the normal travel. Configured to execute the process of controlling the operation of the operating force adjusting means in a form that does not increase the operating force of the holding means beyond the set upper limit for normal control,
The set upper limit immediately after the cutting process is a setting target position for the cutting process work among the plurality of setting target positions, and at least a setting target on the high speed side among the setting target positions for the cutting process work Determined according to the position,
The set upper limit for the normal control immediately after the cutting process, which is set for the same set target position in a state where the set upper limit value for normal control is lower for each of the plurality of set target positions as the set target position on the lower speed side. The point is that the value is set to a value larger than the value.

That is, since the setting upper limit value for normal control for each of the plurality of setting target positions is set to be lower as the setting target position on the low speed side is set, even when the setting target position on the low speed side is set, Even when the set target position on the high speed side is set, the rotational speed of the hydraulic motor can be accurately operated to the low speed side as the driving load increases, so that a large load is not applied to the engine. Will be able to do exactly.
That is, when setting the low-speed set target position among the plurality of set target positions is when the driving force (torque) for traveling is required due to the softness of the ground, the hydraulic pressure Even if the motor is rotated at a low speed, a state in which a large load is applied to the engine tends to occur. However, the upper limit value for normal control for each of a plurality of set target positions is lower for the set target position on the lower speed side. Therefore, it is possible to avoid as much as possible that a large load is applied to the engine for driving the hydraulic motor.

Further, the setting upper limit value immediately after the cutting process is a setting target position for the cutting process work among the plurality of setting target positions, and is set on at least the high speed side of the setting target position for the cutting process work Because it is determined according to the target position, the operating force adjustment process is executed immediately after the cutting process when the load on the engine becomes excessive when turning at the headland in order to travel at high speed. Thus, an excessive load acting on the engine can be suppressed.
That is, when the set target position on the high speed side is selected from the set target positions for the mowing processing work and the vehicle travels at a high speed, when turning toward the side where the next work process is located on the headland, the speed is high. For this reason, there is a possibility that the load acting on the engine becomes large, but in such a case, the operation force adjustment process immediately after the cutting process is executed, and the load acting on the engine is suppressed from becoming excessive. Will be.

  Furthermore, since the set upper limit value for normal control is determined to be a value larger than the set upper limit value immediately after the cutting process determined for the same set target position, the combine is When traveling to the headland and turning toward the side where the next work process is located on the headland, it is possible to accurately reduce the travel speed as the travel load increases, For example, when traveling for work, the traveling speed can be prevented from being unnecessarily reduced.

  Therefore, according to the ninth feature configuration, in addition to the operational effects of the eighth feature configuration, a large load is applied to the engine when traveling at a high speed and a low speed for performing a cutting operation or the like. In addition, while traveling at a high speed, when turning toward the side where the next work process is located on the headland, it is possible to accurately reduce the traveling speed as the traveling load increases. In spite of this, it is possible to provide a combined travel control device that can suppress an unnecessarily decrease in travel speed when traveling for cutting work.

Combine side view Longitudinal front view of the mission case Hydraulic circuit diagram of hydraulic unit Block diagram showing control configuration Hydraulic circuit diagram of hydrostatic continuously variable transmission The figure which shows a traveling state, a standard cutting state, and a low-speed cutting state Flow chart showing control operation Flow chart showing control operation 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 driving | running | working form at the time of performing a cutting process work

Embodiment
As shown in FIG. 1, a cutting unit 2 as a cutting processing unit is supported by a front part of a machine body supported by right and left crawler type traveling devices 1 so as to be movable up and down, and is operated on the right side of the front part of the machine body. The unit 3 is provided, the threshing device 4 is provided on the left side of the rear part of the machine body, and the glen tank 5 is provided on the right side of the rear part of the machine body, thereby constituting a self-decomposing combine that is an example of a combine.
The mowing unit 2 causes cereals planted in the field as the machine progresses, causes the cereals to be caused by the device, cuts the roots of the cereals caused by the cutting blades, and transmits the reaped cereals to the cereal conveying device. It is comprised so that it may convey to the feed chain of a threshing apparatus.

  As shown in FIG. 2, an engine 6 is provided on the lower side of the driving unit 3, a mission case 8 is provided in the vicinity of the center of the left and right of the front part of the airframe, and the hydrostatic continuously variable transmission 7 is connected to the mission case 8. A belt transmission mechanism 9 having a tension clutch function is connected across the input shaft 7a of the hydrostatic continuously variable transmission 7 and the output shaft 6a of the engine 6 connected to the upper portion of the right side.

  As shown in FIG. 2, the output shaft 7b of the hydrostatic continuously variable transmission 7 is inserted into a mission case 8 and connected to a low-speed gear 10 by a spline structure, and the transmission in which the low-speed gear 10 is fixed. A high speed gear 11 is fixed to the shaft 12. A low-speed gear 14 and a high-speed gear 15 are fitted on the output shaft 13 so as to be relatively rotatable, and the low-speed gears 10 and 14 and the high-speed gears 11 and 15 are engaged. The shift member 16 slides on the output shaft 13 by a spline structure. And it is externally fitted so that it can rotate integrally. A tension clutch type cutting clutch 17 is provided by a transmission belt across the output shaft 13 and the input shaft 2a of the cutting unit 2. The power of the output shaft 6a of the engine 6 is configured to be transmitted to the threshing device 4 via a tension clutch type threshing clutch 4A (see FIG. 4).

  As shown in FIG. 2, when the shift member 16 is engaged with the low speed gear 14 (low speed position), the power of the output shaft 7 b of the hydrostatic continuously variable transmission 7 is transmitted via the low speed gears 10, 14 and the shift member 16. When the shift member 16 is engaged with the high-speed gear 15 (high-speed position) when transmitted to the cutting unit 2 in a low-speed state, the power of the output shaft 7b of the hydrostatic continuously variable transmission 7 is transmitted to the high-speed gears 11 and 15 and the shift member 16. Is transmitted to the cutting unit 2 in a high speed state. As described above, the low-speed gears 10 and 14, the high-speed gears 11 and 15, the shift member 16, and the like constitute the cutting transmission 18 that can be shifted in two steps.

Next, the structure of the transmission system (transverse system) of the mission case 8 will be described.
As shown in FIG. 2, a transmission gear 19 is externally fitted to the transmission shaft 20 so as to be relatively rotatable, the transmission gear 19 is engaged with the low-speed gear 10, and a shift member 21 is slid onto the transmission shaft 20 by a spline structure. It is externally fitted so that it can rotate integrally. Transmission gears 22 and 23 are fixed to the transmission shaft 20, and a multi-plate friction parking brake 24 is provided at the end of the transmission shaft 20.

  As shown in FIG. 2, the shift member 21 is normally engaged with the transmission gear 19, and the power of the output shaft 7 b of the hydrostatic continuously variable transmission 7 is transmitted via the low-speed gear 10 and the transmission gear 19. It is transmitted to the shaft 20. At the time of towing the aircraft due to a failure or the like, the right and left traveling devices 1 and the hydrostatic continuously variable transmission 7 can be shut off at the position of the shift member 21 by separating the shift member 21 from the transmission gear 19. Therefore, the airframe can be pulled without receiving the resistance of the hydrostatic continuously variable transmission 7.

  As shown in FIG. 2, the transmission gear 25 is fixed to the transmission shaft 26, and the transmission gears 22 and 25 are engaged. The right and left output gears 27 are fitted on the transmission shaft 26 so as to be relatively rotatable. The right and left output gears 27 are slid onto the transmission shaft 26 by a spline structure. It is externally fitted so that it can rotate integrally. Right and left axles 29 are provided, right and left transmission gears 30 fixed to the right and left axles 29 mesh with the right and left output gears 27, and the ends of the right and left axles 29 The sprocket 1a (refer FIG. 1) of the right and left traveling apparatuses 1 is connected to the part.

  As shown in FIG. 2, a spring 32 is provided between the receiving member 31 fixed to the transmission shaft 26 and the right occlusion portion 28, and a spring 32 is provided between the transmission gear 25 and the left occlusion portion 28. Thus, the right and left occlusion portions 28 are biased by the springs 32 to the occlusion side of the right and left output gears 27. A right oil chamber is formed between the right output gear 27 and the right occlusion portion 28, and a left oil chamber is formed between the left output gear 27 and the left occlusion portion 28. By supplying hydraulic oil to the left oil chamber, the right and left occlusion portions 28 can be separated from the right and left output gears 27 against the spring 32.

  As shown in FIG. 2, an occlusion-type right side clutch 33 is configured between the right output gear 27 and the right occlusion portion 28, and the occlusion is established between the left output gear 27 and the left occlusion portion 28. A left side clutch 33 of the equation is configured. When the right (left) occlusal portion 28 meshes with the right (left) output gear 27, the right (left) side clutch 33 is in a transmission state, and the right (left) occlusal portion 28 becomes right (left). By separating from the output gear 27, the right (left) side clutch 33 is disconnected.

  2, the power of the output shaft 7b of the hydrostatic continuously variable transmission 7 is such that the low speed gear 10, the transmission gear 19, the transmission shaft 20, the transmission gears 22, 25, the transmission shaft 26, The aircraft is transmitted straight to the right and left traveling devices 1 via the left occlusal portion 28, right and left output gears 27, right and left transmission gears 30, and right and left axles 29.

Next, the structure of the transmission system (turning system) of the mission case 8 will be described.
As shown in FIG. 2, a transmission gear 35 externally fitted to the transmission shaft 34 is engaged with a gear portion on the outer peripheral portion of the right occlusion portion 28, and the transmission shaft 34 and the transmission gear 35 are connected to each other. A slow swing clutch 36 is provided therebetween. The slow swing clutch 36 is configured as a frictional multi-plate type and is energized in a shut-off state, and is operated in a transmission state when hydraulic oil is supplied, and is operated in a shut-off state when the hydraulic oil is discharged.

  As shown in FIG. 2, a swing clutch case 37 is fitted on the transmission shaft 26 so as to be relatively rotatable, and a transmission gear 38 fixed to the transmission shaft 34 and a gear portion on the outer periphery of the swing clutch case 37 are engaged with each other. doing. The swing clutch case 37 is configured symmetrically, and a right swing clutch 39 is provided between the swing clutch case 37 and the right output gear 27, and between the swing clutch case 37 and the left output gear 27. A left turning clutch 39 is provided. The right and left turning clutches 39 are configured as a friction multi-plate type, and are operated in a transmission state by supplying hydraulic oil. In this case, in the right and left turning clutch 39, the friction plates are arranged so as to be close to each other, and the right and left turning clutch 39 are in a semi-transmission state even when the hydraulic oil is discharged. ing.

  As a result, as shown in FIG. 2, when the slow swing clutch 36 is operated in the transmission state, the power of the transmission shaft 26 causes the right occlusal portion 28, the transmission gear 35, the slow swing clutch 36, the transmission shaft 34, and the transmission gear. The power is transmitted to the turning clutch case 37 as power that is lower in speed than the transmission shaft 26 in the same direction as the transmission shaft 26. When the right or left side clutch 33 is operated in the disconnected state and the right or left side clutch 39 is operated in the transmission state in the transmission state of the slow rotation clutch 36, the transmission shaft 26 is moved in the same direction as the transmission shaft 26. Also, low speed power is transmitted to the right or left output gear 27.

As shown in FIG. 2, a brake 40 is provided on the left side of the transmission shaft 34. The brake 40 is configured as a friction multi-plate type, and is operated in a braking state by supplying hydraulic oil, and is operated in a released state by discharging the hydraulic oil.
As a result, as shown in FIG. 2, when the brake 40 is operated in the braking state, the turning clutch case 37 is in the braking state via the transmission shaft 34 and the transmission gear 38. In the braking state of the brake 40, when the right or left side clutch 33 is operated in the disconnected state and the right or left turning clutch 39 is operated in the transmission state, the right or left output gear 27 is in the braking state.

  As shown in FIG. 2, a transmission gear 41 is externally fitted to the transmission shaft 34 so as to be relatively rotatable, and the transmission gears 23 and 41 are engaged with each other, and the reverse clutch 42 is interposed between the transmission shaft 34 and the transmission gear 41. Is provided. The reverse clutch 42 is configured as a frictional multi-plate type and is energized in a shut-off state, and is operated in a transmission state when hydraulic oil is supplied, and is operated in a shut-off state when the hydraulic oil is discharged.

  As a result, as shown in FIG. 2, when the reverse clutch 42 is operated in the transmission state, the power of the transmission shaft 20 is transmitted via the transmission gears 23 and 41, the reverse clutch 42, the transmission shaft 34 and the transmission gear 38. It is transmitted to the turning clutch case 37 as power in the direction opposite to that of the shaft 26. In the transmission state of the reverse clutch 42, when the right or left side clutch 33 is operated in the disconnected state and the right or left turning clutch 39 is operated in the transmission state, the power in the direction opposite to that of the transmission shaft 26 is right or left. To the output gear 27.

Next, a hydraulic unit 59 that supplies and discharges hydraulic oil to and from the right and left side clutches 33 (the right and left occlusal portions 28), the right and left turning clutch 39, the slow turning clutch 36, the brake 40, and the reverse rotation clutch 42. Will be described.
As shown in FIGS. 2 and 3, the hydraulic unit 59 is connected to the lower part of the left side portion of the mission case 8. The hydraulic pump 60 is connected to the input shaft 7 a of the hydrostatic continuously variable transmission 7, and the hydraulic pump 60 is driven by the input shaft 7 a of the hydrostatic continuously variable transmission 7. An oil passage 61 extending from the oil pressure unit 59 is connected to the hydraulic unit 59.

  As shown in FIG. 3, a supply oil passage 62 is connected across the transmission case 8 and the hydraulic pump 60, and an oil cooler 63 is provided in the supply oil passage 62. A filter 64 is provided in a portion between the oil cooler 63. Lubricating oil stored in the transmission case 8 passes through the oil cooler 63 and the filter 64 as hydraulic oil and is supplied to the hydraulic pump 60. The hydraulic oil of the hydraulic pump 60 is supplied to the hydraulic unit 59 via the oil passage 61, and the hydraulic oil discharged from each part of the hydraulic unit 59 is returned to the transmission case 8 as will be described later.

  As shown in FIG. 3, inside the hydraulic unit 59, there are a right turn control valve 67, a left turn control valve 68, a first relief valve 69, an unload valve 70, a second relief valve 76, a proportional control valve 71, and a turn switching. A control valve 72 and pilot operation valves 73 and 74 are provided. An oil passage 61 of the hydraulic pump 60 is connected to the hydraulic unit 59, and right and left turning control valves 67 and 68, a first relief valve 69, and an unload valve 70 are connected in parallel to the oil passage 66 connected to the oil passage 61. It is connected.

  As shown in FIG. 3, the right turn control valve 67 is connected to the right side clutch 33 (right occlusion portion 28) and the right turn clutch 39, and the left turn control valve 68 is connected to the left side clutch 33 ( It is connected to the left occlusal portion 28) and the left turning clutch 39. The right and left turning control valves 67 and 68 are configured in an electromagnetic operation type that can be operated to supply positions 67a and 68a and discharge positions 67b and 68b, and are urged to the discharge positions 67b and 68b. The unload valve 70 is configured as an electromagnetic operation type that can be freely operated at the shut-off position 70a and the discharge position 70b, and is urged to the shut-off position 70a.

  As shown in FIG. 3, the second relief valve 76 is connected to the oil passage 75 branched from the right and left side clutches 33 (the right and left occlusal portions 28), and the proportional control valve 71 and the swing are connected to the oil passage 75. The switching control valve 72 is connected in series, and the turning switching control valve 72 is connected to the slow turning clutch 36, the brake 40 and the reverse rotation clutch 42. The proportional control valve 71 is configured as an electromagnetic operation type, and can control the pressure of hydraulic oil. The turning switching control valve 72 is configured in a pilot operation type that can be operated to a slow turning position 72a, a trust turning position 72b, and a super turning position 72c, and is biased to the slow turning position 72a. In this case, the relief pressure of the first relief valve 69 is set to a relatively high value, and the relief pressure of the second relief valve 76 is set to a relatively low value.

As shown in FIG. 3, the pilot operation valve 73 is configured so that the pilot hydraulic oil branched from the oil passage 75 is supplied to the turning switching control valve 72 and operated to the pivot turning position 72 b. The pilot operation valve 74 is configured to supply the pilot hydraulic oil thus supplied to the turning switching control valve 72 and to operate it to the super turning position 72c. A drain oil passage (not shown) is formed on the connection surface (mating surface) between the hydraulic unit 59 and the transmission case 8, and includes a right turn control valve 67, a left turn control valve 68, a first relief valve 69, The hydraulic oil of the unload valve 70, the second relief valve 76, the proportional control valve 71, the turning switching control valve 72, and the pilot operation valves 73 and 74 is returned to the mission case 8 through the drain oil passage.
As shown in FIG. 4, the right and left turning control valves 67 and 68, the unload valve 70, the proportional control valve 71, and the pilot operation valves 73 and 74 are operated as described later by a control device 79 as a control means. .

Next, a straight traveling state by the steering lever 77 will be described.
As shown in FIGS. 1 and 4, a steering lever 77 that can be operated to the right and left is provided in the operation unit 3, and detection information of an operation position detection sensor Q that detects an operation position of the steering lever 77 is indicated by the control device. 79, and the steering lever 77 is configured to be operated at a straight advance position n, right and left first turning positions R1, L1, and right and left second turning positions R2, L2. A dial operation type turning mode switch 78 is provided in the operation unit 3, and operation information of the turning mode switch 78 is inputted to the control device 79, and the turning mode switch 78 is set to a slow turning position, a trust turning position, and a super trust. It has a swivel position.

  As shown in FIGS. 2, 3, and 4, regardless of the operation position of the turning mode switch 78, when the steering lever 77 is operated to the rectilinear position n, the right and left turning control valves 67, 68 are moved to the discharge positions 67b, The unload valve 70 is operated to the discharge position 70b. As a result, the hydraulic oil is discharged from the right and left side clutch 33 (right and left occlusion portion 28) and the right and left turning clutch 39, and the right and left side clutch 33 (right and left occlusion portion 28). Is operated in the transmission state, and the right and left turning clutch 39 are operated in the half transmission state. The proportional control valve 71 operates the slow turn and reverse clutches 36 and 42 to the disconnected state, and the brake 40 to the released state.

  As shown in FIG. 2, the power of the output shaft 7b of the hydrostatic continuously variable transmission 7 is such that the low speed gear 10, the transmission gear 19, the transmission shaft 20, the transmission gears 22, 25, the transmission shaft 26, the right and left occlusions. It is transmitted to the right and left traveling devices 1 through the part 28, the right and left output gears 27, the right and left transmission gears 30, and the right and left axles 29, and the aircraft advances straight.

Next, the slow turning state by the steering lever 77 will be described.
As shown in FIGS. 2 to 4, when the turning mode switch 78 is operated to the slow turning position, the turning switch control valve 72 is operated to the slow turning position 72 a by the pilot operation valves 73 and 74.
Accordingly, when the steering lever 77 is operated to the right first turning position R1, the right turning control valve 67 is operated to the supply position 67a, the unload valve 70 is operated to the cutoff position 70a, and the right side The hydraulic oil is supplied to the clutch 33 (right occlusion portion 28) and the right turning clutch 39, the right side clutch 33 (right occlusion portion 28) is operated to be disconnected, and the right turning clutch 39 is in a transmission state. To be operated.

  As shown in FIG. 2, since the left swing clutch 39 is in a semi-transmission state, the power of the left side clutch 33 (the left occlusion portion 28) is transferred from the left output gear 27 and the left swing clutch 39 to the right. Is transmitted to the right output gear 27 through the turning clutch 39, and the power slightly lower than the transmission shaft 26 in the same direction as the transmission shaft 26 is transmitted to the right output gear 27. As a result, the aircraft gently turns to the right.

  As shown in FIGS. 2, 3, and 4, when the steering lever 77 is operated to the first right turning position R1, the right turning control valve 67 is operated to the supply position 67a as described above, and the unload valve 70 is moved. Simultaneously with the operation to the shut-off position 70a, hydraulic oil begins to be supplied to the slow swing clutch 36 via the proportional control valve 71 and the swing switching control valve 72 (slow swing position 72a), and the steering lever 77 is The proportional control valve 71 increases the operating pressure of the slow turning clutch 36 as the right first turning position R1 is operated to the right second turning position R2.

  As shown in FIGS. 2, 3, and 4, as the operating pressure of the slow swing clutch 36 is increased by the proportional control valve 71 based on the operation position of the steering lever 77, the power of the transmission shaft 26 is changed to the right. And the transmission shaft 26 in the same direction as the transmission shaft 26 via the occlusal portion 28, the transmission gear 35, the slow turning clutch 36, the transmission shaft 34, the transmission gear 38, the turning clutch case 37 and the right turning clutch 39. It is transmitted to the right output gear 27 as power.

  In this case, as shown in FIG. 2, the power from the left side clutch 33 (the left occlusal portion 28) and the power from the slow turning clutch 36 are simultaneously transmitted to the right output gear 27. In the range where the operating pressure of the slow swing clutch 36 is low, the power from the left side clutch 33 (left occlusion portion 28) overcomes the power from the slow swing clutch 36, and the left side clutch 33 (left occlusion) The right output gear 27 is driven by the power from the section 28). As a result, the airframe gradually turns to the right when the operating pressure of the slow swing clutch 36 is low.

  Next, when the operating position of the steering lever 77 approaches the right second turning position R2 and the operating pressure of the slow turning clutch 36 becomes high, the power from the slow turning clutch 36 is changed to the left side as shown in FIG. Overcoming the power from the clutch 33 (the left occlusal portion 28), the right output gear 27 is driven by the power from the slow turning clutch 36. In this state, the right output gear 27 is driven by the power from the slow turning clutch 36, rather than the right output gear 27 being driven by the power from the left side clutch 33 (the left occlusal portion 28). However, the right output gear 27 is driven at a low speed, and the aircraft turns slowly to the right.

  As shown in FIGS. 2 to 4, when the steering lever 77 is operated to the left first turning position L1, the left turning control valve 68 is operated to the supply position 68a, and the unload valve 70 is operated to the cutoff position 70a. Then, hydraulic oil is supplied to the left side clutch 33 (the left occlusion portion 28) and the left turning clutch 39, and the left side clutch 33 (the left occlusion portion 28) is operated in a disconnected state to turn left. The clutch 39 is operated to the transmission state. At the same time, the same operation as described above is performed, and the aircraft gradually turns to the left. When the steering lever 77 is operated from the left first turning position L1 to the left second turning position L2, the same operation as described above is performed, and the aircraft turns slowly to the left.

Next, the belief turning state by the steering lever 77 will be described.
As shown in FIGS. 2 to 4, when the turning mode switch 78 is operated to the belief turning position, the turning switch control valve 72 is operated to the belief turning position 72 b by the pilot operation valves 73 and 74.
Accordingly, when the steering lever 77 is operated to the right first turning position R1, the right turning control valve 67 is operated to the supply position 67a, the unload valve 70 is operated to the cutoff position 70a, and the right side The hydraulic oil is supplied to the clutch 33 (right occlusion portion 28) and the right turning clutch 39, the right side clutch 33 (right occlusion portion 28) is operated to be disconnected, and the right turning clutch 39 is in a transmission state. To be operated. In this case, since the left turning clutch 39 is in a semi-transmission state, the aircraft gradually turns to the right.

  As shown in FIGS. 2 to 4, when the steering lever 77 is operated to the right first turning position R1, the right turning control valve 67 is operated to the supply position 67a as described above, and the unload valve 70 is shut off. Simultaneously with the operation of 70a, the hydraulic oil begins to be supplied to the brake 40 via the proportional control valve 71 and the turn switching control valve 72 (the pivot turn position 72b), and the steering lever 77 is moved to the right first. The proportional control valve 71 increases the operating pressure of the brake 40 as the turning position R1 is operated to the second right turning position R2.

  As shown in FIGS. 2 to 4, the operating pressure of the brake 40 is increased by the proportional control valve 71 based on the operation position of the steering lever 77, and accordingly, the transmission shaft 34, the transmission gear 38, and the swing clutch case 37. And the braking force is applied to the right output gear 27 via the right turning clutch 39.

  In this case, as shown in FIG. 2, the power from the left side clutch 33 (the left occlusal portion 28) and the braking force of the brake 40 are simultaneously transmitted to the right output gear 27. In a range where the operating pressure of the brake 40 is low, the power from the left side clutch 33 (the left occlusion portion 28) overcomes the braking force of the brake 40 and the force from the left side clutch 33 (the left occlusion portion 28) The right output gear 27 is driven by the power. As a result, when the operating pressure of the brake 40 is in a low pressure range, the aircraft gradually turns to the right.

  Next, when the operating position of the steering lever 77 approaches the right second turning position R2 and the operating pressure of the brake 40 becomes high, the braking force of the brake 40 is applied to the left side clutch 33 (left The power output from the occlusal portion 28) is overcome, the braking force of the brake 40 causes the right output gear 27 to enter the braking state, and the aircraft turns right.

  As shown in FIGS. 2 to 4, when the steering lever 77 is operated to the left first turning position L1, the left turning control valve 68 is operated to the supply position 68a, and the unload valve 70 is operated to the cutoff position 70a. Then, hydraulic oil is supplied to the left side clutch 33 (the left occlusion portion 28) and the left turning clutch 39, and the left side clutch 33 (the left occlusion portion 28) is operated in a disconnected state to turn left. The clutch 39 is operated to the transmission state. At the same time, the same operation as described above is performed, and the aircraft gradually turns to the left. When the steering lever 77 is operated from the left first turning position L1 to the left second turning position L2, the same operation as described above is performed, and the aircraft turns to the left.

Next, the super turning state by the steering lever 77 will be described.
As shown in FIGS. 2 to 4, when the turning mode switch 78 is operated to the super turning position, the turning control valve 72 is operated to the super turning position 72 c by the pilot operation valves 73 and 74.
Accordingly, when the steering lever 77 is operated to the right first turning position R1, the right turning control valve 67 is operated to the supply position 67a, the unload valve 70 is operated to the cutoff position 70a, and the right side The hydraulic oil is supplied to the clutch 33 (right occlusion portion 28) and the right turning clutch 39, the right side clutch 33 (right occlusion portion 28) is operated to be disconnected, and the right turning clutch 39 is in a transmission state. To be operated. In this case, since the left turning clutch 39 is in a semi-transmission state, the aircraft gradually turns to the right.

  As shown in FIGS. 2 to 4, when the steering lever 77 is operated to the right first turning position R1, the right turning control valve 67 is operated to the supply position 67a as described above, and the unload valve 70 is shut off. Simultaneously with the operation of 70a, the hydraulic oil starts to be supplied to the reverse rotation clutch 42 via the proportional control valve 71 and the turn switching control valve 72 (super pivot turn position 72c). The proportional control valve 71 increases the operating pressure of the reverse rotation clutch 42 as the first turning position R1 is operated to the right second turning position R2.

  2-4, as the operating pressure of the reverse clutch 42 is increased by the proportional control valve 71 based on the operation position of the steering lever 77, the power of the transmission shaft 20 is transmitted to the transmission gear 23, 41, the reverse rotation clutch 42, the transmission shaft 34, the transmission gear 38, the turning clutch case 37, and the right turning clutch 39 are transmitted to the right output gear 27 as power in the direction opposite to that of the transmission shaft 26.

  In this case, as shown in FIG. 2, the power from the left side clutch 33 (the left occlusal portion 28) and the power from the reverse clutch 42 are transmitted to the right output gear 27 at the same time. In the range where the operating pressure of the reverse clutch 42 is low, the power from the left side clutch 33 (the left occlusion portion 28) overcomes the power from the reverse clutch 42 and the left side clutch 33 (the left occlusion portion 28). ) Drives the right output gear 27. As a result, when the operating pressure of the reverse clutch 42 is in a low pressure range, the aircraft gradually turns to the right.

  Next, when the operating position of the steering lever 77 approaches the right second turning position R2 and the operating pressure of the reverse clutch 42 becomes high, the power from the reverse clutch 42 is changed to the left side clutch 33 as shown in FIG. The right output gear 27 is driven by the power from the reverse clutch 42 by overcoming the power from the (left occlusal portion 28). In this state, the right output gear 27 is driven in the opposite direction with respect to the left output gear 27, and the aircraft turns to the right.

  As shown in FIGS. 2 to 4, when the steering lever 77 is operated to the left first turning position L1, the left turning control valve 68 is operated to the supply position 68a, and the unload valve 70 is operated to the cutoff position 70a. Then, hydraulic oil is supplied to the left side clutch 33 (the left occlusion portion 28) and the left turning clutch 39, and the left side clutch 33 (the left occlusion portion 28) is operated in a disconnected state to turn left. The clutch 39 is operated to the transmission state. At the same time, the same operation as described above is performed, and the aircraft gradually turns to the left. When the steering lever 77 is operated from the left first turning position L1 to the left second turning position L2, the same operation as described above is performed, and the aircraft turns to the left.

Next, the hydraulic circuit structure of the hydrostatic continuously variable transmission 7 will be described.
As shown in FIG. 5, the hydrostatic continuously variable transmission 7 includes an axial plunger type variable displacement hydraulic pump 7P and an axial plunger type variable displacement hydraulic motor 7M. The hydraulic pump 7P and the hydraulic motor 7M are connected to each other. It is configured to be connected by a pair of oil passages 7c. A charge pump 44 is connected to the input shaft 7 a of the hydrostatic continuously variable transmission 7, and the charge pump 44 is driven by the input shaft 7 a of the hydrostatic continuously variable transmission 7.

  As shown in FIG. 5, a bypass oil passage 83 is connected across the oil passage 7 c of the hydrostatic continuously variable transmission 7, and a charge oil passage 45 extending from the charge pump 44 is connected to the bypass oil passage 83. The charge oil passage 45 is provided with a filter 49. A check valve 84, a throttle portion 85, and a relief valve 86 are provided between a portion of the bypass oil passage 83 to which the charge oil passage 45 is connected and the oil passage 7c of the hydrostatic continuously variable transmission 7. The relief pressure of the relief valve 86 is set to the highest pressure allowed as a whole of the hydrostatic continuously variable transmission 7. A supply oil passage 47 is connected across an oil tank 46 provided separately from the mission case 8 and the charge pump 44, and a filter 48 is provided in the supply oil passage 47.

  As shown in FIG. 5, a relief valve 50 is connected to the charge oil passage 45, and the relief valve 50 is connected to a case 51 that houses the hydrostatic continuously variable transmission 7. An oil passage 52 is connected across the case 51 and the oil tank 46, and an oil cooler 53 is provided in the oil passage 52. With the above structure, the hydraulic oil in the oil tank 46 is supplied to the oil passage 7c of the hydrostatic continuously variable transmission 7 through the filter 48, the supply oil passage 47, the charge pump 44, and the charge oil passage 45, and surplus. The hydraulic oil is discharged to the case 51 through the relief valve 50. The hydraulic oil from each part of the hydrostatic continuously variable transmission 7 is discharged to the case 51, and the hydraulic oil in the case 51 passes through the oil passage 52 and the oil cooler 53 and is returned to the oil tank 46.

Next, the operation structure of the hydraulic pump 7P of the hydrostatic continuously variable transmission 7 will be described.
As shown in FIGS. 4 and 5, the hydraulic pump 7P of the hydrostatic continuously variable transmission 7 is configured to be steplessly variable in the neutral state, the forward side and the reverse side, and is in a neutral position N, the forward side F, and the reverse side. A shift lever 43 (corresponding to a hydraulic pump operating tool) that can be operated on the side R is provided in the operating unit 3, and the shift lever 43 and the swash plate 7Pa of the hydraulic pump 7P of the hydrostatic continuously variable transmission 7 are linked to each other. 80 are mechanically linked. Although not illustrated, a friction type holding mechanism for holding the operated shift lever 43 in its position is provided.

  As shown in FIG. 4, an electric motor 55 for applying an operating force (assist force) to the speed change lever 43 and an operation sensor (FIG. 5) for detecting that the speed change lever 43 is about to be operated to the forward side F or the reverse side R. The electric motor 55 is operated by the control device 79 as follows based on the detection value of the operation sensor.

  As shown in FIG. 4, when the shift lever 43 is about to be operated to the forward side F, this operation is detected by the operation sensor, and the electric motor 55 is activated to apply the operating force to the forward side F to the shift lever 43. give. When the shift lever 43 is about to be operated to the reverse side R, this operation is detected by the operation sensor, and the electric motor 55 is activated to apply an operation force to the reverse side R to the shift lever 43.

  As shown in FIG. 4, the swash plate 7Pa of the hydraulic pump 7P in the hydrostatic continuously variable transmission 7 is operated by the shift lever 43 so that the swash plate 7Pa of the hydraulic pump 7P is set to the neutral position N, the forward side F, and the reverse side. By operating the electric motor 55, the transmission lever 43 can easily operate the swash plate 7Pa of the hydraulic pump 7P to the forward side F and the reverse side R. When the operation of the shift lever 43 toward the forward side F and the reverse side R stops, the electric motor 55 also stops, and the swash plate 7Pa of the hydraulic pump 7P is held at that position.

Next, operations of the hydraulic motor 7M, the harvesting clutch 17, the threshing clutch 4A, and the harvesting transmission 18 of the hydrostatic continuously variable transmission 7 will be described.
As shown in FIG. 4, the grip 43 a at the top of the shift lever 43 is provided with a travel shift switch 81 at the bottom of the lateral surface of the grip 43 a of the shift lever 43, and the grip 43 a of the shift lever 43 is A cutting shift switch 82 is provided at the upper portion of the rear surface portion. The travel speed change switch 81 and the mowing speed change switch 82 are configured as push buttons that are urged to return to the return side (projection side), and operation signals of the travel speed change switch 81 and the mowing speed change switch 82 are input to the control device 79. Is done.

As shown in FIGS. 4 and 5, the hydraulic motor 7M of the hydrostatic continuously variable transmission 7 is configured to be steplessly variable in the range of the high speed position H and the low speed position L, and the hydrostatic continuously variable transmission apparatus. 7 is provided with an operating cylinder 56 (corresponding to the holding means) that holds the swash plate 7Ma (corresponding to the capacity changing operation section) of the hydraulic motor 7M that moves to the low speed side with an operating force that moves it to the high speed side. It has been.
As the position of the swash plate 7Ma of the hydraulic motor 7M, a potentiometer 89 (corresponding to a position detecting means) for detecting the position of the piston of the operating cylinder 56 is provided, and the position of the piston of the operating cylinder 56 is detected by the potentiometer 89. The position of the swash plate 7Ma of the hydraulic motor 7M is detected, and the detection value P of the potentiometer 89 is input to the control device 79.

As shown in FIGS. 4 and 5, the oil passage 57 branches from the charge oil passage 45, and the oil passage 57 is connected to an oil chamber 56 a that operates the operation cylinder 56 to the high speed side. A spring 56b for urging is provided. A pressure control valve 58 constituted by an electromagnetic proportional valve is provided in the oil passage 57 as an operation force adjusting means for changing and adjusting the operation force of the operation cylinder 56, and the pressure in the oil chamber 56a of the operation cylinder 56 increases. Then, when the operating cylinder 56 operates the swash plate 7Ma of the hydraulic motor 7M to the high speed side against the traveling load and the urging force of the spring 56b, and the pressure in the oil chamber 56a of the operating cylinder 56 decreases, the operating cylinder 56 tilts. The plate 7Ma is operated to the low speed side by the traveling load and the urging force of the spring 56b.
In other words, the operation cylinder 56 is a hydraulic cylinder that is changed by hydraulic pressure to which an operation force for moving the swash plate 7Ma of the hydraulic motor 7M to the high speed side is supplied, and the pressure control valve 58 is an operation cylinder 56. Is configured to change and adjust the pressure of the hydraulic pressure supplied to.

  As shown in FIG. 4, an operation motor 65 is provided, and the operation motor 65, the reaping clutch 17, the threshing clutch 4 </ b> A, and the reaping transmission device 18 are mechanically linked. The clutch 4A and the cutting transmission 18 are operated. By the operating motor 65, the cutting clutch 17 and the threshing clutch 4A are operated in the disconnected state and the cutting transmission 18 is operated to the low speed position, and the cutting clutch 17 and the threshing clutch 4A are operated in the transmission state and the cutting transmission 18 The three states appear in the state in which the cutting clutch 17 and the threshing clutch 4A are operated in the transmission state and the cutting transmission 18 is operated in the high speed position.

  As shown in FIG. 6, a moving traveling state, a standard cutting state, and a low-speed cutting state are set. In the traveling state, the standard cutting state, and the low-speed cutting state, as shown in FIGS. 4 and 6, the control device 79. Accordingly, the pressure control valve 58, the operation motor 65, and the display unit 87 provided in the operation unit 3 are operated as follows.

In the traveling state, the swash plate 7Ma of the hydraulic motor 7M in the hydrostatic continuously variable transmission 7 is operated to the high speed position H for traveling, the reaping clutch 17 and the threshing clutch 4A are operated in the disconnected state, and the reaping transmission device. 18 is a state where the low speed position is operated, and the high speed position H is displayed on the display unit 87.
In the standard reaping state, the swash plate 7Ma of the hydraulic motor 7M in the hydrostatic continuously variable transmission 7 is operated to the middle speed position M for reaping work, the reaping clutch 17 and the threshing clutch 4A are operated to the transmission state, and the reaping speed change. In this state, the device 18 is operated to the low speed position, and the medium speed position M is displayed on the display unit 87.
In the low-speed cutting state, the swash plate 7Ma of the hydraulic motor 7M in the hydrostatic continuously variable transmission 7 is operated to the low-speed position L for the overturning cutting operation, the cutting clutch 17 and the threshing clutch 4A are operated in the transmission state, and the cutting shift is performed. The device 18 is in a state of being operated to the high speed position, and the low speed position L is displayed on the display unit 87. This low-speed cutting state is selected when cutting a crop that is heavily laid down.

As shown in FIG. 6, the control device 79 is configured to operate the pressure control valve 58 and the operation motor 65 as follows based on the pushing operation of the travel shift switch 81 and the cutting shift switch 82.
When the travel shift switch 81 is pushed and operated in the state where the mobile travel state is set, the standard cutting state is set. When the travel shift switch 81 is pushed and operated in the state where the standard cut state is set, the mobile travel state is set. Is set. Thus, every time the travel shift switch 81 is pushed, the traveling state and the standard cutting state are alternately set.
In this case, even if the cutting shift switch 82 is pushed in a state where the traveling state is set, the pushing operation is ignored and the traveling state is maintained. When the travel shift switch 81 is pushed, and the cutting shift switch 82 is pushed in a state where the standard cutting state is set, the low-speed cutting state is set.

When the cutting shift switch 82 is pushed in the state where the standard cutting state is set, the low-speed cutting state is set. When the cutting shift switch 82 is pushed in a state where the low-speed cutting state is set, the standard cutting state is set. Thus, every time the cutting shift switch 82 is pushed, the standard cutting state and the low-speed cutting state are alternately set.
In this case, even if the travel shift switch 81 is pressed in a state where the low-speed cutting state is set, this pressing operation is ignored and the low-speed cutting state is maintained. If the travel shift switch 81 is pushed and operated in a state where the standard cut state is set by pushing the cut shift switch 82, the traveling state is set.

As described above, the high speed position H, the medium speed position M, and the low speed position L are determined as the set target positions of the swash plate 7Ma of the hydraulic motor 7M in the hydrostatic continuously variable transmission 7. 81 and the mowing shift switch 82 function as selection means for selecting one of the set target positions.
Then, the control device 79 maintains the swash plate 7Ma of the hydraulic motor 7M at the target position set by the travel shift switch 81 and the cutting shift switch 82 among the plurality of set target positions. An operation force adjustment process for controlling a current value to be energized is executed.

Further, even if the control device 79 moves the swash plate 7Ma of the hydraulic motor 7M to the lower speed side than the set target position as an operation force adjustment process, the control device 79 exceeds the set upper limit value for normal control and the tilt of the hydraulic motor 7M is increased. The operation force adjustment process for normal traveling is performed to control the pressure control valve 58 in a form that does not increase the operation force for moving the plate 7Ma to the high speed side.
When the explanation is added, the current value energized to the pressure control valve 58 corresponds to the operating force for moving the swash plate 7Ma of the hydraulic motor 7M to the high speed side by the operating cylinder 56. As shown in FIG. A current detection sensor D for detecting a current value a energized to the pressure control valve 58 and a drive circuit 93 for the pressure control valve 58 are provided.
Then, corresponding to each of the high speed position H, the medium speed position M, and the low speed position L as set target positions for maintaining the swash plate 7Ma of the hydraulic motor 7M, it corresponds to the set upper limit value for normal control. The set upper limit current values A1, A2, and A3 for normal control are set so as to be lower as the set target position on the low speed side is lowered, and the control device 79 is based on the detection information of the current detection sensor D, and controls the pressure control valve. The current value a energizing the pressure control valve 58 is controlled in such a manner that the current value a energizing 58 does not increase beyond the set upper limit current values A1, A2 and A3 for normal control (for normal running). It is configured.

In this way, the current value supplied to the pressure control valve 58 is controlled in such a manner that the current value a supplied to the pressure control valve 58 does not increase beyond the set upper limit current values A1, A2, and A3 for normal control. Thus, it is possible to suppress an excessive load on the engine 6.
That is, when the swash plate 7Ma of the hydraulic motor 7M is maintained at the high speed position H, the traveling load increases, and the swash plate of the hydraulic motor 7M is operated with an operating force corresponding to the set upper limit current value A1 for normal control. If 7Ma cannot be maintained at the high speed position H, the swash plate 7Ma of the hydraulic motor 7M will move to a lower speed side than the high speed position H, and the traveling speed will be reduced and the load on the engine 6 will be prevented from increasing. Will do.
Similarly, when the swash plate 7Ma of the hydraulic motor 7M is maintained at the medium speed position H, the traveling load increases, and the operating force corresponding to the set upper limit current value A2 for normal control causes the hydraulic motor 7M to If the swash plate 7Ma cannot be maintained at the medium speed position M, the swash plate 7Ma of the hydraulic motor 7M moves to the lower speed side than the medium speed position H, the traveling speed becomes lower, and the load on the engine 6 increases. Will be suppressed.

The low speed position L as the set target position of the swash plate 7Ma of the hydraulic motor 7M is set to a position slightly higher than the movement limit of the swash plate 7Ma to the low speed side, and the swash plate 7Ma of the hydraulic motor 7M. Is maintained at the low speed position H, the traveling load increases, and the swash plate 7Ma of the hydraulic motor 7M cannot be maintained at the low speed position L with the operating force corresponding to the set upper limit current value A3 for normal control. Although the swash plate 7Ma of the hydraulic motor 7M moves to the lower speed side than the low speed position L, the movement amount is small and the traveling speed is only a small amount, and the load on the engine 6 is reduced. It is not very effective in mitigating.
Incidentally, the high speed position H as the set target position of the swash plate 7Ma of the hydraulic motor 7M is set to a position slightly on the low speed side from the limit of movement of the swash plate 7Ma to the high speed side.

In addition, as the operation force adjustment process, the control device 79 exceeds the set upper limit value immediately after the cutting process, even if the swash plate 7Ma of the hydraulic motor 7M moves to the lower speed side than the set target position. An operation force adjustment process immediately after the cutting process is performed to control the pressure control valve 58 in a form that does not increase the operation force for moving the swash plate 7Ma to the high speed side.
That is, the control device 79 performs the operation force adjustment process immediately after the cutting process during the cutting-out traveling that is immediately after the cutting process, and the medium speed with the swash plate 7Ma of the hydraulic motor 7M as the set target position. This is executed when maintaining the position M, and even when the cutting blade is traveling, the swash plate 7Ma of the hydraulic motor 7M is maintained at the high speed position H or the low speed position L as the set target position, and the cutting blade is traveling. If not, that is, during non-cutting travel, the above-described operation force adjustment processing for normal travel is executed.
Note that the determination of whether or not cutting cutting is in progress will be described later.

  When the operation force adjustment process immediately after the cutting process is described, the setting upper limit current value immediately after the cutting process corresponding to the setting upper limit value immediately after the cutting process is the medium speed position M in the operating force adjustment process for normal traveling. Is set smaller than the set upper limit current value A2 for normal control. Specifically, the set upper limit current value immediately after the cutting process is set to a value (A2-β) obtained by subtracting the set amount β from the set upper limit current value A2 for normal control. Incidentally, the set amount β is a value smaller than the difference between the set upper limit current value A2 corresponding to the medium speed position M and the set upper limit current value A3 corresponding to the low speed position L. In other words, the set upper limit current value A2 for normal control is set larger by the set amount β than the set upper limit current value A2-β for immediately after the cutting process.

Therefore, when the control device 79 determines that the above-described cutting-off travel is being performed when the medium speed position M is selected as the set target position for maintaining the swash plate 7Ma of the hydraulic motor 7M as described above, An operation force adjustment process immediately after the process is executed.
In the operation force adjustment process immediately after the cutting process, the set upper limit current value A2- immediately after the cutting process in which the current value a energizing the pressure control valve 58 is smaller than the set upper limit current value A2 for normal travel. Since β does not increase beyond β, the swash plate 7Ma of the hydraulic motor 7M is operated to the lower speed side than the medium speed position M with a smaller traveling load than when the normal driving operation force adjustment process is executed. Thus, the traveling load acting on the engine 6 is reduced.
Incidentally, as described above, since the set upper limit current value A2 for normal travel is set larger than the set upper limit current value A2-β for immediately after the cutting process, the operation force adjustment process for immediately after the cutting process is performed immediately after the cutting process. Thus, the process of controlling the current value to be supplied to the pressure control valve 58 is performed in such a manner that the current value a to be supplied to the pressure control valve 58 is increased beyond the set upper limit current value A2-β.

As described above, when the traveling load increases, the swash plate 7Ma of the hydraulic motor 7M in the hydrostatic continuously variable transmission 7 is set to the high speed position H, the medium speed position M, and the low speed position L as the set target positions. Although the load on the engine 6 is reduced by moving it from the low speed side to the low speed side, when the load on the engine 6 is excessive in spite of reducing the traveling speed in this way, the control device 79 In the hydrostatic continuously variable transmission 7, the swash plate 7Pa of the hydraulic pump 7P is configured to perform a deceleration operation process in which the electric motor 55 operates the deceleration side.
In other words, as shown in FIG. 4, a rotation speed sensor 90 that detects the rotation speed E of the engine 6 is provided, and a detection value E <b> 1 of the rotation speed sensor 90 is input to the control device 79. The operation unit 3 is provided with a dial operation type accelerator operation tool 91 configured by a volume or the like, and operation position information of the accelerator operation tool 91 is input to the control device 79. The accelerator operating tool 91 sets the rotational speed E2 of the engine 6 in a no-load state, and although not described in detail, an electronic governor (not shown) of the engine 6 based on the operating position information of the accelerator operating tool 91. Is configured to be operated.
Then, the control device 79 determines the difference between the rotation speed E2 of the engine 6 in the no-load state set by the accelerator operation tool 91 and the rotation speed E1 of the engine 6 detected by the rotation speed sensor 90 (corresponding to the engine load). If the difference is larger than the set value E3 for overload determination, the shift lever 43 is operated to the low speed side by the electric motor 55, and the swash plate of the hydraulic pump 7P in the hydrostatic continuously variable transmission 7 is obtained. It is configured to operate 7 Pa to the low speed side.

Next, determination during cutting cutting will be described.
As shown in FIG. 1, a stock source sensor U that detects and detects the presence of a stock of cereal that is conveyed by a cereal transport device that transports the chopped cereal to a threshing device 4 As shown in FIG. 4, detection information of the stock sensor U is input to the control device 79.

  Further, based on the detection information of the operation position detection sensor Q in which the control device 79 detects the operation position of the steering lever 77, the steering lever 77 exceeds the set angle (for example, 2 degrees) from the neutral position n to the left and right. When it is swung, it is detected that it is in a turning state, and it is detected that it is in a non-turning state if the steering lever 77 is not swung beyond the neutral position n and to the left and right beyond a set angle (for example, 2 degrees). It is configured as follows. That is, the operation position detection sensor Q is configured to function as a turning state detection unit that detects whether or not the turning state is in a turning state.

Further, the control device 79 determines the difference (corresponding to the engine load) between the rotational speed E2 of the engine 6 in the no-load state set by the accelerator operating tool 91 and the rotational speed E1 of the engine 6 detected by the rotational speed sensor 90. ), And whether or not the difference is larger than the set value for determining the cut-off travel, in other words, whether or not the engine load is greater than or equal to the set amount is detected. Incidentally, the setting value for determining the cut-off travel is sufficiently smaller than the setting value E3 for determining the overload. For example, assuming that the engine 6 rotates 3000 times per minute, the setting value for cut-off travel discrimination is set to a value of about 100 times per minute, whereas the setting for overload discrimination The value E3 is set to a value of about 300 to 500 times per minute.
In the present embodiment, the rotation speed sensor 90 functions as an engine load detection unit that detects an engine load acting on the engine 6.

Then, after the control device 79 detects that the stock sensor U has switched from the cutting operation state to the non-cutting operation state, a set time (for example, 3 seconds) after the switching is detected. ), When it is detected that the engine is in a turning state and the engine load is equal to or greater than the set amount, it is determined that the cutting operation is in progress, and the stock sensor U performs a non-cutting operation from the cutting operation state. Even after it is detected that the vehicle has been switched to a state, the turning state is not detected or the engine load is greater than or equal to the set amount during the set time (for example, 3 seconds) after the switch is detected. If it is not detected that the vehicle is running without cutting, and if it is determined that the vehicle is not cutting, the operation force adjustment process immediately after the cutting process is performed as described above. Run It becomes door.

  Furthermore, when the control device 79 determines that the cutting cutting is in progress, that is, when the operation force adjustment process for the cutting process is being performed, the stock sensor U starts from the non-cutting work state. It is configured to determine that the vehicle is in the non-cutting travel when it is detected that the switch is made to the cutting work state or the switch is made from the turning state to the non-turning state, and If it is determined that the trimming is not being performed, as described above, the operation force adjustment process for normal traveling is executed instead of the operation force adjustment process for immediately after the cutting process.

In addition, it is detected by the rotation speed sensor 90 when it is determined that the control device 79 is running through the cutting, that is, when the operation force adjustment process immediately after the cutting process is being executed. When the engine speed is sampled and the sampled engine speed increases by a set amount (for example, 30 revolutions per minute) from the lowest previously sampled speed (corresponding to the maximum load of the engine load) (engine The load is reduced to a set amount), and is determined to be in non-cutting travel, and an operation force adjustment process for normal travel is executed instead of the operation force adjustment process for immediately after the cutting process. It is configured as follows.
In other words, during the cut-off travel, it is determined that the non-cut-off travel is being performed as early as possible, and the operation force adjustment process for normal travel is executed as early as possible.

Hereinafter, the control operation of the control device 79 will be described based on the flowcharts shown in FIGS.
FIG. 7 shows the main flow. When the power is turned on, the initial setting is performed first (# 1). In this initial setting, the traveling state is set.
Once the initial setting has been made, it is next determined whether or not the vehicle is in a traveling state (# 2). If in the traveling state, whether or not the traveling shift switch 81 has been operated, that is, the traveling shift switch 81 is It is determined whether or not it is turned on (# 3), and if the travel shift switch 81 is not operated, the process for moving travel state is performed in which the mowing clutch 17 and the threshing clutch 4A are disconnected and the mowing transmission 18 is lowered. (# 4) and a high-speed operation process (# 5) for maintaining the swash plate 7Ma of the hydraulic motor 7M in the hydrostatic continuously variable transmission 7 at the high-speed position H is executed.
Next, when the load of the engine 6 is excessive, a deceleration operation process is performed in which the swash plate 7Pa of the hydraulic pump 7P in the hydrostatic continuously variable transmission 7 is operated to the deceleration side by the electric motor 55 (# 6). , The process returns to the process of determining whether or not the traveling state is # 2.

  When it is determined that the travel shift switch 81 has been operated in # 3, it is assumed that it is a change to the standard reaping state, and the reaping clutch 17 and the threshing clutch 4A are set in the transmission state and the reaping transmission device 18 is set to a low speed The mowing state process (# 10) and the medium speed operation process (# 11) for maintaining the swash plate 7Ma of the hydraulic motor 7M in the hydrostatic continuously variable transmission 7 at the medium speed position M are executed, and then # 6 shifts to the deceleration operation process.

  If it is determined in # 2 that the vehicle is not in the traveling state, it is determined whether or not it is in the standard cutting state (# 7). If it is in the standard cutting state, it is determined whether or not the traveling shift switch 81 is turned on. Discriminate (# 8). If the travel shift switch 81 is not operated, it is determined whether or not the cutting shift switch 82 is operated, that is, whether or not the cutting shift switch 82 is turned on (# 9), and the cutting shift switch 82 is operated. If not, the process proceeds to the standard cutting state process of # 10.

If it is determined at # 8 that the travel shift switch 81 has been turned ON, it is determined that the travel shift state has been changed, and the process proceeds to # 4 for travel travel state processing.
When it is determined in # 9 that the cutting shift switch 82 has been turned ON, it is determined that the cutting is to the low-speed cutting state, and the cutting clutch 17 and the threshing clutch 4A are set in the transmission state to make the cutting transmission 18 high speed. The state process (# 13) and the low speed operation process (# 14) for maintaining the swash plate 7Ma of the hydraulic motor 7M in the hydrostatic continuously variable transmission 7 at the low speed position L are executed, and then the deceleration of # 6 is performed. Transition to operation processing.

  If it is determined in # 7 that it is not in the standard cutting state, that is, if it is determined in the low speed cutting state, it is determined whether or not the cutting shift switch 82 is turned on in # 12, and the cutting shift switch 82 is turned on. If it is determined that the change is made to the standard cutting state, the process proceeds to the standard cutting state process of # 10, and it is determined that the cutting shift switch 82 is turned ON in # 12. , # 13 shifts to the low-speed cutting state process.

FIG. 8 shows the control operation of the above-described high-speed operation process, and this high-speed operation process corresponds to the control device 79 executing the operation force adjustment process for normal traveling.
First, it is determined whether or not the detection value P of the potentiometer 89 for detecting the position of the piston of the operating cylinder 56 is a position corresponding to the high speed position H (# 21), and the detection value P is a position corresponding to the high speed position H. If it is, the process returns to the main flow.
If it is determined in # 21 that the detected value P is not a position corresponding to the high speed position H, it is determined whether or not the detected value P is on the higher speed side than the position corresponding to the high speed position H (# 22). When it is determined that the speed is high, a value obtained by subtracting the set amount α from the current target current value A is set as a new target current value A (# 23), and the current detected by the current detection sensor D A current control process for instructing the drive circuit 93 to give a current increase / decrease command is executed so that the value a becomes the new target current value A (# 24), and then the process returns to the main flow.

When it is determined in # 22 that the detected value P is not on the higher speed side than the position corresponding to the high speed position H, that is, the detected value P is on the lower speed side than the position corresponding to the high speed position H, the target current value A Is smaller than the set upper limit current value A1 corresponding to the high speed position H (# 25). If it is determined that the current value is smaller, the current target current value A is set to # 26. A value obtained by adding the set amount α is set as a new target current value A, and thereafter, the process proceeds to a current control process of # 24.
If it is determined at # 25 that the target current value A is not smaller than the set upper limit current value A1 corresponding to the high speed position H, the current target current value A is set to the set upper limit current value A1 at # 27. Then, the process proceeds to the current control process of # 24.

FIG. 9 shows the control operation of the above-described medium-speed operation process. This medium-speed operation process includes a control device 79 that performs an operation force adjustment process for normal travel and an operation force adjustment process for immediately after the cutting process. It corresponds to performing.
First, a cutting travel determination process is performed to determine whether or not the cutting travel is in progress (# 40). Next, the detection value P of the potentiometer 89 that detects the position of the piston of the operation cylinder 56 is medium speed. It is determined whether or not the position corresponds to the position M (# 41). If the detected value P is a position corresponding to the medium speed position M, the process returns to the main flow.
If it is determined in # 41 that the detected value P is not a position corresponding to the medium speed position M, it is determined whether or not the detected value P is higher than the position corresponding to the medium speed position M ( # 42) When it is determined that the speed is high, a value obtained by subtracting the set amount α from the current target current value A is set as a new target current value A (# 43) and detected by the current detection sensor D. The current control process for instructing the drive circuit 93 to give a current increase / decrease command is executed so that the current value a to become the new target current value A (# 44), and then the process returns to the main flow.

When it is determined in # 42 that the detected value P is not on the higher speed side than the position corresponding to the medium speed position M, that is, the detected value P is on the lower speed side than the position corresponding to the medium speed position H, It is determined whether or not the result determined in the cutting-cut traveling determination process is in the cutting-cut traveling (# 45).
When it is determined in # 45 that it is not cutting-cut traveling, that is, when it is determined that it is not cutting-cut traveling, the set upper limit current value A2 for normal control is set to the determination set value S ( # 46). If it is determined in # 45 that the cutting is running, the set current value A2-β immediately after cutting is set to the setting value S for determination (# 47).

Next, it is determined whether or not the target current value A is smaller than the determination setting value S (# 48). If it is determined that the target current value A is smaller, the current target current value A is determined in # 49. A value obtained by adding the set amount α to is set as a new target current value A, and then the process proceeds to a current control process of # 44.
If it is determined at # 48 that the target current value A is not smaller than the determination set value S, the determination set value S is set as the target current value A at # 50, and the current control of # 44 is performed. It will move to processing.

  In this medium speed operation process, when it is determined that the cutting is running at # 45, the set current value A2-β immediately after cutting is set to the setting value S for determination at # 47. By performing the process, the control device 79 executes the operation force adjustment process immediately after the cutting process, and when it is determined in # 45 that it is not cutting cutting, that is, non- By determining that the upper limit current value A2 for normal control is set to the setting value S for determination in # 46 when it is determined that the cutting is being carried out, the control device 79 performs normal operation. An operation force adjustment process for traveling is executed.

FIG. 10 shows the control operation of the low-speed operation process described above, and this low-speed operation process corresponds to the control device 79 executing the normal driving operating force adjustment process.
First, it is determined whether or not the detected value P of the potentiometer 89 for detecting the position of the piston of the operating cylinder 56 is a position corresponding to the low speed position L (# 61), and the detected value P is a position corresponding to the low speed position L. If it is, the process returns to the main flow.
If it is determined in # 61 that the detected value P is not a position corresponding to the low speed position L, it is determined whether or not the detected value P is higher than the position corresponding to the low speed position L (# 62). When it is determined that the speed is high, a value obtained by subtracting the set amount α from the current target current value A is set as a new target current value A (# 63), and the current detected by the current detection sensor D Current control processing for instructing a current increase / decrease command to the drive circuit 93 is executed so that the value a becomes the new target current value A (# 64), and then the process returns to the main flow.

When it is determined in # 62 that the detected value P is not on the high speed side from the position corresponding to the low speed position L, that is, the detected value P is on the low speed side than the position corresponding to the low speed position H, the target current value A Is smaller than the set upper limit current value A3 corresponding to the low speed position L (# 65). If it is determined that the current value is smaller, the current target current value A is set to # 66. A value obtained by adding the set amount α is set as a new target current value A, and then the process proceeds to # 64 current control processing.
If it is determined at # 65 that the target current value A is not smaller than the set upper limit current value A3 corresponding to the low speed position L, the current target current value A is set to the set upper limit current value A3 at # 67. Then, the process proceeds to # 64 current control processing.

FIG. 11 shows the control operation of the deceleration operation process described above.
The difference (corresponding to the running load) between the rotational speed E2 of the engine 6 in the no-load state set by the accelerator operation tool 91 and the rotational speed E1 of the engine 6 detected by the rotational speed sensor 90 is obtained, and the difference is obtained. Is determined to be larger than the set value E3 (# 80). If it is determined that it is not larger, the process returns to the main flow.

If it is determined at # 80 that the difference between the rotational speed E2 of the engine 6 in the no-load state and the rotational speed E1 of the engine 6 detected by the rotational speed sensor 90 is larger than the set value E3, the electric motor 55, the set amount deceleration process for operating the shift lever 43 to the set amount low speed side is executed (# 81).
The set amount deceleration operation process is not described in detail, but the shift lever 43 is moved from the current position to a position decelerated by the set amount based on the detection information of the position detecting means for detecting the position of the shift lever 43. The electric motor 55 is operated.

FIG. 12 shows the control operation of the above-described cutting-running traveling determination process.
First, it is determined whether or not the cutting-cut traveling has been set (# 90).
If it is determined that the setting has not been completed in # 90, the time after the detection information of the stock sensor U switches from the cutting work state to the non-cutting work state in # 91 is within 3 seconds as the set time. That is, it is determined that the elapsed time after the detection information of the stock sensor U is turned from ON to OFF is within 3 seconds, it is determined that the turn is started in # 92, In # 93, the engine load is equal to or greater than the set amount, that is, the difference between the rotation speed E2 of the engine 6 in the no-load state and the rotation speed E1 of the engine 6 detected by the rotation speed sensor 90 (corresponding to the engine load). ) Is larger than the set value for cutting-off travel discrimination, it is set at # 94 that cutting-off travel is in progress.

  When it is determined at # 91 that the elapsed time since the detection information of the stock sensor U has been turned from ON to OFF is not within 3 seconds, when it is determined at # 92 that the turn has not started Furthermore, if it is determined at # 93 that the engine load is less than the set amount, it is set at # 99 that the vehicle is not cutting.

  If it is determined at # 90 that cutting-cut traveling is already set, the lowest among the engine speeds E1 of the engine 6 detected by the rotation speed sensor 90 after setting cutting-cut traveling is set. Processing for storing the rotational speed is executed (# 95). In this storing process, if the rotation speed to be sequentially sampled is lower than the previously stored rotation speed, the rotation speed is stored. If the rotation speed is higher than the previously stored rotation speed, the previously stored rotation speed is continued. Is stored.

  Thereafter, when it is determined at # 96 that the stock sensor U has detected the cutting work state, when it is determined at # 97 that the turn has been completed, and at # 98, the engine 6 is rotated. If any of the cases where it is determined that the number E1 has increased by more than the set number of revolutions than the number of revolutions stored in the process of # 95 is satisfied, the non-cutting travel is being performed at # 99. Is set.

  Further, it is not determined in # 96 that the stock sensor U has detected the cutting operation state, it is not determined in # 97 that the turn has been completed, and further, in # 98, the rotational speed E1 of the engine 6 is determined. If it is not determined that the engine speed has increased by more than the set rotational speed from the stored rotational speed in the process of # 95, the process proceeds to # 94.

[Another embodiment]
Hereinafter, another embodiment of the present invention will be described.

(1) In the above embodiment, a hydraulic cylinder that is changed by the pressure of the hydraulic pressure to which the operating force is supplied is exemplified as the holding means, but other configurations can be used.
For example, a drive rotator for moving the operation unit to the high speed side, and the drive rotator and the operation unit are linked to each other using a friction transmission mechanism whose transmission force can be changed and adjusted. By changing and adjusting the force, it is possible to change and adjust the operating force for moving the operating unit to the high speed side.
The operating force adjusting means for changing and adjusting the operating force of the holding means is variously changed according to the configuration of the holding means.

(2) In the above embodiment, the case where the set target positions for maintaining the operation unit are three positions different from the high speed position, the medium speed position, and the low speed position is exemplified. It may be carried out in a form that is set as the set target position, or may be carried out in a form that sets four or more positions as the set target positions.

(3) In the above embodiment, the case where the set upper limit value for normal control is set when executing the operation force adjustment process for normal running is illustrated, but the set upper limit value for normal control is not set. You may make it implement.
Further, as described in the above embodiment, even when the upper limit value for normal control is set, the low speed side of each of the three set target positions for maintaining the operation unit is set as in the above embodiment. For example, instead of separately setting the target target position so as to be lower, only the set upper limit value corresponding to the high speed position may be determined.

(4) In the above-described embodiment, the combine provided with the trigger device is illustrated, but the present invention can be applied to various types of combine such as a configuration not including the trigger device.

(5) In the above embodiment, when the engine is overloaded, the case where the deceleration operation process for decelerating the hydraulic motor of the hydrostatic continuously variable transmission is performed is illustrated. However, this deceleration operation process is not provided. You may implement.

(6) In the above embodiment, when the cutting operation state detecting means detects that the cutting operation state has been switched to the non-cutting operation state, a set time (for example, 3 seconds) elapses from that time. During this period, when it is detected that the vehicle is turning and the engine load is detected to be greater than or equal to the set amount, it is determined that the cutting is running and the operating force adjustment process immediately after cutting is performed. In the case where the set time (for example, 3 seconds) elapses from when the cutting operation state detection unit detects that the cutting operation state is switched to the non-reaching operation state. After the condition is removed, it is detected by the cutting operation state detecting means that the cutting operation state is switched to the non-cutting operation state, and then the turning state is detected and the engine load is set to the set amount. That is more When it is detected, as is in cutting omission traveling may be configured to perform an operation force adjustment processing for immediately cutting.
By the way, the condition from when it is detected by the cutting operation state detecting means that the cutting operation state is switched to the non-cutting operation state until the set time (for example, 3 seconds) elapses is set in the threshing device. This is a condition for determining that there is a large amount of remaining processed material, and it is easier to avoid that it is unnecessary to discriminate that cutting is being carried out when this condition is added. Become.

(7) In the above embodiment, when the cutting operation state detecting means detects that the cutting operation state has been switched to the non-cutting operation state, a set time (for example, 3 seconds) elapses from that time. During this period, when it is detected that the vehicle is turning and the engine load is detected to be greater than or equal to the set amount, it is determined that the cutting is running and the operating force adjustment process immediately after cutting is performed. However, after the cutting operation state detecting means detects that the cutting operation state is switched to the non-cutting operation state, the operation force adjustment processing immediately after the cutting operation is simply performed. It may be configured to execute.

(8) In the above embodiment, when the cutting operation state detecting means detects that the cutting operation state has been switched to the non-cutting operation state, a set time (for example, 3 seconds) elapses from that time. During this period, when it is detected that the vehicle is turning and the engine load is detected to be greater than or equal to the set amount, it is determined that the cutting is running and the operating force adjustment process immediately after cutting is performed. In this example, the condition for determining that the engine load is detected to be equal to or greater than the set amount is removed, and the cutting operation state detecting means switches from the cutting operation state to the non-cutting operation state. When it is detected that the vehicle is turning, if it is detected that the vehicle is turning during the set time (for example, 3 seconds), Operation force adjustment It may be configured to perform a physical.
In this case, simply remove the condition from when the cutting operation state detection means detects that the cutting operation state is switched to the non-reaching operation state until a set time (for example, 3 seconds) elapses. When the cutting operation state detection means detects that the cutting operation state has been switched to the non-cutting operation state and then the turning state is detected, it is assumed that the cutting operation is in progress. The operation force adjustment process immediately after cutting may be configured to be executed.

(9) In the above-described embodiment, the stock source sensor that detects and operates the culm transported by the culm transporting device is exemplified as the cutting operation state detection unit. For example, the cultivar of the field located in front of the machine body Various forms such as a sensor for detecting whether or not there is a cutting state can be used as the cutting operation state detecting means.

(10) In the above embodiment, the case where the rotational speed sensor for detecting the rotational speed of the engine is used as the engine load detecting means is exemplified. However, the torque sensor for detecting the torque output from the engine is used as the engine load detecting means. Various configurations for detecting the engine load, such as detecting the engine load, can be changed.

(11) In the above embodiment, the setting upper limit current value immediately after the cutting process as the setting upper limit value immediately after the cutting process is determined by subtracting the set amount from the setting upper limit current value for normal control. The set amount to be subtracted from the set upper limit current value for normal control may be set to a larger amount by the control means as the engine load increases. In this way, when the engine load is large, the rotational speed of the hydraulic motor can be easily operated to the low speed side, and the traveling load can be sufficiently reduced.

2 Mowing processing unit 4 Threshing device 6 Engine 7 Hydrostatic continuously variable transmission 7M Hydraulic motor of hydrostatic continuously variable transmission 7Ma Operation unit (swash plate)
46 Holding means (hydraulic cylinder)
48 Operating force adjusting means (Electromagnetic proportional valve)
79 Control means 81, 82 Selection means 89 Position detection means

Claims (9)

A combine travel control device configured to transmit engine power to a mowing processing unit, a threshing device, and a hydrostatic continuously variable transmission for travel,
Holding means for holding the operation part for changing the capacity of the variable capacity hydraulic motor of the hydrostatic continuously variable transmission device from the set target position to the low speed side with an operating force for moving the high speed side;
Operating force adjusting means for changing and adjusting the operating force of the holding means;
Position detecting means for detecting the position of the operation unit;
A cutting work state detecting means for detecting whether or not a cutting work state;
Control means for executing an operation force adjustment process for controlling the operation of the operation force adjustment means so as to maintain the operation unit at a set target position based on detection information of the position detection means is provided,
After the control means detects that the cutting work state detection means has switched from the cutting work state to the non-cutting work state, the operation unit controls the set target as the operation force adjustment process. The operation immediately after the cutting process that controls the operation of the operating force adjusting means in a form that does not increase the operating force of the holding means exceeding the set upper limit value immediately after the cutting process even when moving to a lower speed side than the position. A combine traveling control device configured to execute force adjustment processing. A turning state detecting means for detecting whether or not the turning state is provided;
After the control means detects that the cutting work state has been switched from the cutting work state to the non-cutting work state, the turning state detection means detects that the turning state is being turned. When the operation force adjustment process immediately after the cutting process is executed, the cutting work state detecting means detects that the cutting work state is switched to the non-cutting work state. However, when the turning state detection means does not detect that the turning state is detected, the operation force adjustment process exceeds the set upper limit value immediately after the cutting process and increases the operation force of the holding means. The combine travel control device according to claim 1, wherein the travel control device is configured to execute an operation force adjustment process for normal travel for controlling the operation of the operation force adjusting means.   After the control means detects that the cutting work state detection means has switched from the cutting work state to the non-cutting work state, the set time has elapsed since the switching was detected. When the turning state detecting means detects that the turning state is in the meantime, an operation force adjustment process immediately after the cutting process is executed, and the cutting work state detecting means performs the cutting operation. Even after it is detected that the working state has been switched to the non-reaping working state, the turning state detecting means is in the period from when the switching has been detected until the set time elapses. When the turning state is not detected, the operation force adjustment unit controls the operation of the operation force adjustment unit in a form in which the operation force of the holding unit is increased beyond the set upper limit immediately after the cutting process. Normal running Combine the travel control device of the operation force adjustment processing of Configured claim 2 to run. A turning state detecting means for detecting whether or not the turning state, and an engine load detecting means for detecting an engine load acting on the engine are provided;
After the control means detects that the cutting work state detection means has switched from the cutting work state to the non-reaching work state, and the turning state detection means is in a turning state. When it is detected that the engine load detected by the engine load detection means is greater than or equal to a set amount, an operating force adjustment process immediately after the cutting process is executed, and the cutting work state detection means Even if it is detected that the cutting operation state is switched to the non-cutting operation state, the turning state detection means does not detect that the turning state is detected, or the engine load detection means When it is not detected that the engine load is greater than or equal to the set amount, the operating force adjusting means is operated in such a manner that the operating force of the holding means is increased beyond the set upper limit value immediately after the cutting process. Combine of claim 1 is configured to perform a normal operation force adjustment processing for running for controlling the running control system.   When the control means is executing the operation force adjustment process immediately after the cutting process, it is detected by the cutting work state detection means that the non-cutting work state is switched to the cutting work state. Then, after that, the traveling control device for a combine according to any one of claims 2 to 4, which is configured to execute the operation force adjustment processing for normal traveling.   When the control means is executing the operation force adjustment process immediately after the cutting process, it is detected by the cutting work state detection means that the cutting work state is switched from the non-cutting work state. Alternatively, when the turning state detecting means detects that the turning state is switched to the non-turning state, the operation force adjustment process for the normal traveling is executed thereafter. Item 5. The travel control device for a combine according to any one of Items 2 to 4.   The engine load detected by the engine load detecting means for detecting the engine load acting on the engine when the control means is executing the operation force adjustment process immediately after the cutting process is the cutting process. The configuration is such that when the set amount is reduced from the previously detected maximum load during the execution of the immediately following operating force adjustment process, the normal driving operation force adjustment process is executed thereafter. The travel control device for a combine according to any one of 6. As the set target position, a plurality of set target positions that are different positions are determined,
Selection means for selecting any of the plurality of set target positions is provided,
As the operation force adjustment process, the control unit operates the operation force adjustment unit so as to maintain the operation unit at the set target position selected by the selection unit among the plurality of set target positions. The travel control device for a combine according to any one of claims 2 to 7, which is configured to execute a process to be controlled. Even if the operation unit moves to a lower speed side than the set target position, the control means is set to a value larger than the set upper limit value immediately after the cutting process as the operation force adjustment process for the normal travel. Configured to execute the process of controlling the operation of the operating force adjusting means in a form that does not increase the operating force of the holding means beyond the set upper limit for normal control,
The set upper limit immediately after the cutting process is a setting target position for the cutting process work among the plurality of setting target positions, and at least a setting target on the high speed side among the setting target positions for the cutting process work Determined according to the position,
The set upper limit for the normal control immediately after the cutting process, which is set for the same set target position in a state where the set upper limit value for normal control is lower for each of the plurality of set target positions as the set target position on the lower speed side. 9. The combine travel control device according to claim 8, wherein the travel control device is defined in a state where the value is larger than the value.

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