JP7050589B2 - Harvester travel control device - Google Patents

Description

The present invention relates to a traveling control device for a harvester that harvests grains and the like.

For example, in a combine equipped with a hydrostatic continuously variable transmission (HST), the hydraulic pump is driven by the power of the engine, and the hydraulic motor is driven by the oil discharged from the hydraulic pump to power the hydraulic motor. Is transmitted to the left and right crawler. When the left and right crawlers are driven at the same speed, the aircraft moves straight forward and backward, and the left and right crawlers are driven with a speed difference, so that the aircraft turns left and right.

Unlike passenger cars and tractors, combines are generally not equipped with a braking device that brakes the aircraft. Therefore, in the combine, when an abnormality that makes it impossible to acquire information used for driving control (driving control information) such as a sensor failure related to driving occurs, the engine is stopped (operated) in order to ensure safety. Prohibition) will take measures to prohibit driving at all.

Japanese Unexamined Patent Publication No. 2008-57358

However, if the combine is prohibited from traveling while traveling on the road, it may be dangerous depending on the traveling conditions such as when crossing a railroad crossing or traveling on a slope. In addition, if traveling is prohibited while the combine is in the field, it is necessary to replace or repair the traveling-related parts in the field, or to replace or repair the traveling-related parts in the repair shop. The combine must be lifted by a crane and removed from the field, and the combine must be placed on a loading vehicle and transported to the repair site.

An object of the present invention is to provide a travel control device for a harvester, which can improve safety and convenience when an abnormality in which travel control information cannot be acquired occurs in the harvester.

In order to achieve the above object, the traveling control device of the harvester according to the present invention is an engine, a pair of left and right traveling devices, a pump driven by the power of the engine, and a motor driven by the pressure oil discharged from the pump. A travel control device used in a harvester including a power transmission device for transmitting the power of a motor to a travel device, wherein the information acquisition means for acquiring travel control information and the information acquisition means are travel control information. The normal control means that controls the power transmission device by the normal method that uses the travel control information at the normal time when the information can be acquired, and the contraction that does not use the travel control information when the information acquisition means cannot acquire the travel control information. It includes a contraction control means for controlling a power transmission device by a method.

According to this configuration, a power transmission device is interposed between the engine and the pair of left and right traveling devices. The power transmission device includes a pump driven by the power of the engine and a motor driven by the pressure oil discharged from the pump. The power of the motor is transmitted to the pair of left and right traveling devices.

At normal times, the power transmission device is controlled by a conventional method, and travel control information is used in the control. When an abnormality that cannot acquire travel control information occurs in the harvester, the control method of the power transmission device is switched from the normal method to the degenerate method that does not use the travel control information according to the occurrence of the abnormality, and then. The power transmission device is controlled by the degenerate method. As a result, even if an abnormality occurs in the harvester that cannot acquire travel control information, the power transmission device can be degenerately operated, power is transmitted from the power transmission device to the travel device, and the harvester continues to travel. Can be made to.

Therefore, when an abnormality occurs in which the harvester cannot acquire travel control information while crossing the railroad crossing, the harvester can cross the railroad crossing and the risk of the harvester getting stuck in the railroad crossing can be reduced. In addition, when an abnormality occurs in which the harvester cannot acquire travel control information while traveling on a slope, it is possible to suppress the power transmission from the power transmission device to the travel device, and the harvester is intended by the driver. On the contrary, the risk of going down a slope can be reduced. Furthermore, when an abnormality occurs in the field where the harvester cannot acquire travel control information, the harvester can be self-propelled to escape from the field.

Therefore, it is possible to improve the safety and convenience when an abnormality that cannot acquire the traveling control information occurs in the harvester.

The harvester detects the position of the shift operating member, which is operated from the neutral position to one side to move the harvester forward, and is operated from the neutral position to the other side to move the harvester backward. An operation position detecting means may be provided. In this configuration, the information acquisition means acquires the position information of the shift operation member as travel control information based on the detection signal input from the operation position detection means, and the normal control means is acquired by the information acquisition means. When the position information of the shift operation member is information indicating the position on one side with respect to the neutral position, the power transmission device is controlled so that the power transmission device outputs the power in the direction of advancing the harvester to the traveling device. , When the position information of the shift operation member acquired by the information acquisition means is information indicating the position on the other side with respect to the neutral position, the power transmission device outputs the power in the direction of moving the harvester backward to the traveling device. The power transmission device may be controlled as such.

In addition to the shift operation member, the harvester may be provided with a switch operation member that can switch between the first state and the second state. When the harvester is equipped with a threshing device, the switch operating member is a cutting depth switch that selectively sets the length of the culm entering the threshing device to the first length and the second length shorter than the first length. You may. Then, the contraction control means is a traveling device from the power transmission device when the switch operation member is in the first state at the time of abnormality in which the position information of the shift operation member cannot be acquired because the detection signal of the operation position detection means is not input. The power transmission device is controlled so that the power in the direction of moving the harvester forward is output, and when the switch operating member is in the second state, the power in the direction of moving the harvester backward is output from the power transmission device to the traveling device. The power transmission device may be controlled so as to be performed. As a result, the harvester can be moved forward and backward by operating the switch operating member in the event of an abnormality in which the position information of the shift operating member cannot be acquired.

The power transmission device may further include a servo mechanism for controlling the position of the pump swash plate of the pump. In this configuration, the control means usually sets the target position of the pump swash plate according to the position of the shift operation member based on the position information of the shift operation member acquired by the information acquisition means, and positions the pump swash plate. It is preferable to feedback-control the servo mechanism so that the servo mechanism matches the target position. On the other hand, the degenerate control means sets the target position of the pump swash plate to a fixed position on the forward side when the switch operating member is in the first state, and when the switch operating member is in the second state, the pump swash plate is set. The target position may be set to a fixed position on the reverse side to control the servo mechanism in a feed-forward manner. As a result, a certain amount of pressure oil can be discharged from the pump at the time of an abnormality in which the position information of the shift operation member cannot be acquired, and a certain amount of power can be transmitted from the motor to the power transmission device.

The harvester further comprises a control device communicably connected to the travel control device, the control device for adjusting the position detected by the operating position detecting means to match the actual position of the shift operating member. The operation position adjustment data may be retained. In this configuration, the information acquisition means acquires the position information of the shift operation member from the detection signal input from the operation position detection means using the operation position adjustment data, and the degeneration control means is the operation position adjustment data by the information acquisition means. When an abnormality cannot be obtained because the position information of the shift operation member cannot be obtained, the target position of the pump diagonal plate is set according to the position detected by the operation position detecting means, and the servo mechanism is feed-forward controlled. You may.

Further, when the power transmission device further includes a servo mechanism for controlling the position of the pump swash plate of the pump, and the harvester is provided with a swash plate position detecting means for detecting the position of the pump swash plate. , The information acquisition means acquires the position information of the pump swash plate as travel control information based on the detection signal input from the swash plate position detection means, and the normal control means is based on the position information of the pump swash plate. , The target position of the pump swash plate is set, the servo mechanism is feedback-controlled so that the position of the pump swash plate matches the target position, and the contraction control means sets the target position of the pump swash plate and the servo. The mechanism may be feed-forward controlled.

In such a case, the harvester further comprises a control device communicably connected to the travel control device so that the control device aligns the position detected by the swashplate position detecting means with the actual position of the pump swashplate. The swash plate position adjustment data for adjusting to may be retained. Then, the information acquisition means acquires the position information of the pump swash plate from the detection signal input from the swash plate position detection means using the swash plate position adjustment data, and the swash plate position adjustment means by the information acquisition means adjusts the position of the pump swash plate. In the event of an abnormality where the position information of the pump swash plate cannot be obtained because data cannot be used, the target position of the pump swash plate is set based on the position detected by the swash plate position detecting means, and the servo mechanism is fed. Forward control may be used.

According to the present invention, even if an abnormality that cannot acquire travel control information occurs in the harvester, the harvester can continue to travel, so that the safety and convenience at the time of the abnormality can be improved. Can be done.

It is a right side view which shows the front part of the combine which concerns on one Embodiment of this invention. It is a figure which shows the structure of the HST mounted on a combine. It is a block diagram which shows the main part of the electric composition of a combine. It is a block diagram which shows the concrete structure for traveling control.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<Combine>
FIG. 1 is a right side view showing the front part of the combine 1 according to the embodiment of the present invention.

The combine 1 is a work vehicle that cuts the culm and threshs the culm while traveling in the field. The body 11 of the combine 1 is supported by a pair of left and right traveling devices 12. In the traveling device 12, a crawler having an ability to run on rough terrain is adopted in order to enable the combine 1 to travel in the field.

The machine body 11 is provided with a driver's cab 13, a cutting device 14, a threshing device 15, and a grain tank 16.

The driver's cab 13 is arranged above the front end portion of the traveling device 12. The driver's cab 13 is provided with a driver's seat 17 on which an operator sits. For example, an operation panel 18 operated by an operator is provided in front of and to the left of the driver's seat 17. The operation panel 18 is provided with a main shift lever 21, a steering lever, and the like.

The main shift lever 21 is provided so as to be tiltable in the front-rear direction. By tilting the main shift lever 21, the forward and reverse speeds of the airframe 11 can be switched, and the forward or reverse speed thereof can be changed.

The steering lever 22 is provided so as to be tiltable in the left-right direction and the front-back direction. By tilting the steering lever 22 in the left-right direction, the machine body 11 can be switched between going straight, turning left, and turning right. Further, the cutting device 14 can be raised and lowered by tilting the steering lever 22 in the front-rear direction.

The cutting device 14 is arranged in front of the traveling device 12. The cutting device 14 is provided with a weeding tool 23 at its front end and a cutting blade 24 behind the weeding tool 23. The weeding tool 23 and the cutting blade 24 are supported by the cutting device frame 25F. At the rear end of the cutting device frame 25F, a cutting horizontal frame 25L extending in the left-right direction is provided. One end of the cutting main frame 25M is connected to the cutting horizontal frame 25L. The cutting main frame 25M extends rearward from the cutting horizontal frame 25L, and the other end portion (provided in the front lowering portion and the rear end portion) is rotatably connected to the frame of the machine body 11. By tilting the steering lever 22 in the front-rear direction, a cylinder (not shown) can be operated to swing the cutting main frame 25M, and the swing causes the weeding tool 23 and the cutting blade 24 to move to the ground. It goes up and down to the ascending position where it rises high from the ground and the descending position where the weeding tool 23 and the cutting blade 24 descend near the ground. When the machine body 11 advances with the weeding tool 23 and the cutting blade 24 in the descending position, the culm is separated by the weeding tool 23 while the culm is separated by the culm 23. Mowed by.

The threshing device 15 and the grain tank 16 are arranged side by side above the traveling device 12 and behind the cutting device 14. The cut culm is transported to the threshing device 15 by the reaping device 14. The threshing device 15 transports the stock root side of the grain culm backward by the threshing feed chain, and supplies the tip side of the grain culm to the handling chamber to thresh. Then, the grains are transported from the threshing device 15 to the grain tank 16, and the grains are stored in the grain tank 16. A grain discharge auger 26 is continuously provided in the grain tank 16, and the grains stored in the grain tank 16 can be discharged to the outside of the machine by the grain discharge auger 26.

<Stepless variable transmission>
FIG. 2 is a diagram showing the configuration of HST31.

The combine 1 is equipped with an HST (Hydro Static Transmission) 31. The HST 31 shifts and outputs the power of the engine 32 (see FIG. 3). The power output by the HST 31 is transmitted to the left and right traveling devices 12 via a turning mechanism (not shown). As the turning mechanism, for example, a state in which a plurality of hydraulic clutches are provided and constant speed power is transmitted to the left and right traveling devices 12 by a combination of engaging (on) and disengaging (disengaging) of the clutches. A state in which power lower than the power transmitted to one of the left and right traveling devices 12 is transmitted to the other, a state in which power is transmitted to only one of the left and right traveling devices 12, and a state in which power is transmitted to one of the left and right traveling devices 12. A structure that can take a state in which the power to be generated and the power in the opposite direction are transmitted to the other is adopted.

The HST 31 has a closed circuit configuration in which the hydraulic pump 41 and the hydraulic motor 42 are connected by the first oil passage 43 and the second oil passage 44 so that the hydraulic oil circulates between the hydraulic pump 41 and the hydraulic motor 42. Have. The first oil passage 43 is connected to the first port 45 of the hydraulic pump 41 and the first port 46 of the hydraulic motor 42. The second oil passage 44 is connected to the second port 47 of the hydraulic pump 41 and the second port 48 of the hydraulic motor 42.

Further, the HST 31 is provided with a charge pump 51. The charge pump 51 is a fixed-capacity hydraulic pump, and the hydraulic oil is discharged to the charge oil passage 53 by the rotation of the pump rotation shaft 52. The charge oil passage 53 is connected to the first oil passage 43 via the first check valve 54, and is connected to the second oil passage 44 via the second check valve 55. Further, the charge oil passage 53 is connected to the oil tank 57 via the charge relief valve 56.

The function of the charge relief valve 56 maintains the hydraulic pressure of the charge oil passage 53 at a predetermined charge pressure. When the oil pressure of the first oil passage 43 becomes lower than the oil pressure of the charge oil passage 53, that is, the charge pressure, the first check valve 54 is opened, and the first oil passage from the charge oil passage 53 via the first check valve 54 is opened. Hydraulic oil is supplied to 43. Further, when the hydraulic pressure of the second oil passage 44 becomes lower than the charge pressure, the second check valve 55 is opened, and hydraulic oil is supplied from the charge oil passage 53 to the second oil passage 44 via the second check valve 55. Will be done. As a result, the hydraulic pressure of the first oil passage 43 and the second oil passage 44 is maintained above the charge pressure.

The HST 31 is an integrated type in which a hydraulic pump 41, a hydraulic motor 42, a first oil passage 43, a second oil passage 44, a first check valve 54, a second check valve 55, a charge relief valve 56, and the like are housed in a single case. It is configured as an HST.

The hydraulic pump 41 is a variable capacity type swash plate type piston pump, and includes a cylinder block, a plurality of pistons radially arranged in the cylinder block, a pump swash plate on which the pistons slide, and the like. The hydraulic pump 41 and the charge pump 51 have a pump rotating shaft 52 in common, and the cylinder block is provided so as to rotate integrally with the pump rotating shaft 52.

An electronically controlled servo cylinder 58 is provided to change the inclination angle of the pump swash plate of the hydraulic pump 41. The servo cylinder 58 has a first pressure chamber 62 to which hydraulic pressure is supplied from the pressure control valve 61 on the forward side, and a second pressure chamber 64 to which hydraulic pressure is supplied from the pressure control valve 63 on the reverse side. Further, the servo cylinder 58 has a rod 65 that directly moves by the differential pressure between the first pressure chamber 62 and the second pressure chamber 64, and the tilt angle of the pump swash plate is changed by the direct movement of the rod 65. Will be done. The servo cylinder 58, the pressure control valve 61 on the forward side, and the pressure control valve 63 on the reverse side constitute a servo mechanism 66 that controls the inclination angle of the pump swash plate of the hydraulic pump 41.

The larger the inclination angle of the pump swash plate with respect to the axis of the pump rotation shaft 52 of the hydraulic pump 41 (the rotation axis of the cylinder block), the smaller the amount of hydraulic oil discharged from the hydraulic pump 41, and the inclination angle of the pump swash plate is 90. When °, the discharge of hydraulic oil from the hydraulic pump 41 is stopped. Further, when the inclination angle of the pump swash plate exceeds 90 ° (when the inclination is reversed), the discharge direction of the hydraulic oil from the hydraulic pump 41 is reversed when the inclination angle is less than 90 °.

The hydraulic motor 42 is a variable displacement type swash plate type piston motor, and a motor rotating shaft 71, a cylinder block that rotates integrally with the motor rotating shaft 71, a plurality of pistons radially arranged in the cylinder block, and pistons are pressed against the hydraulic motor 42. It is equipped with a motor diagonal plate. When the inclination angle of the motor diagonal plate with respect to the axis of the motor rotary shaft 71 of the hydraulic motor 42 is constant, the larger the amount of hydraulic oil supplied to the hydraulic motor 42, that is, the larger the amount of hydraulic oil discharged from the hydraulic pump 41. , The number of rotations of the motor rotation shaft 71 increases.

Further, when the amount of hydraulic oil supplied to the hydraulic motor 42 is constant, the larger the inclination angle of the motor diagonal plate, the lower the rotation speed of the motor rotation shaft 71. An auxiliary speed change piston 72 is provided to change the inclination angle of the motor swash plate of the hydraulic motor 42. A low-speed switching valve 73 and a high-speed switching valve 74 are connected to the auxiliary speed change piston 72. The low-speed switching valve 73 is turned on, the high-speed switching valve 74 is turned off, and hydraulic pressure is supplied from the low-speed switching valve 73 to the auxiliary transmission piston 72, so that the rod 75 of the auxiliary transmission piston 72 is positioned at a low speed position. , The tilt angle of the motor swash plate becomes relatively large. On the other hand, the low speed switching valve 73 is turned off, the high speed switching valve 74 is turned on, and hydraulic pressure is supplied from the high speed switching valve 74 to the auxiliary speed change piston 72, so that the rod 75 of the auxiliary speed change piston 72 is moved to the high speed position. It is located and the tilt angle of the motor swash plate becomes relatively small. Therefore, by switching the low-speed switching valve 73 and the high-speed switching valve 74 on / off, the position of the motor swash plate is set to the position on the high-speed side where the rotation speed of the motor rotation shaft 71 becomes relatively large, and the rotation of the motor rotation shaft 71. It is possible to switch to two stages with the position on the low speed side where the number is relatively small.

<Electrical configuration>
FIG. 3 is a block diagram showing a main part of the electrical configuration of the combine 1.

The combine 1 is equipped with a single main ECU (Electronic Control Unit) 81 for overall overall control and a plurality of ECUs for individual specific control. The ECU for individual specific control includes, for example, an engine ECU 82 for controlling the engine 32 and a traveling control ECU 83 for controlling the HST 31. The main ECU 81, the engine ECU 82, and the travel control ECU 83 each include a microcontroller unit (MCU: Micro Controller Unit).

The main ECU 81 is communicably connected to each ECU for individual specific control, that is, an engine ECU 82, a traveling control ECU 83, and the like. Further, a meter panel 84 arranged on the operation panel 18 (see FIG. 1) of the driver's cab 13 is connected to the main ECU 81 as a control target. The main ECU 81 controls various instruments and indicators such as a mileage meter provided on the meter panel 84. For example, when an abnormality occurs in the combine 1, the main ECU 81 transmits information about the abnormality to the meter panel 84 and causes the display to display the content of the abnormality. The display comprises, for example, a liquid crystal display.

The travel control ECU 83 includes a main shift lever sensor 85 that outputs a detection signal according to the operation position of the main shift lever 21, and a steering lever sensor 86 that outputs a detection signal according to the operation position of the steering lever 22. They are connected and their detection signals are input.

Further, the travel control ECU 83 is connected to a switch 87 provided on the operation panel 18 of the driver's cab 13, which is used for purposes other than travel control and turning control, and a signal corresponding to the state of the switch 87 is connected to the switch 87. Is entered. As an example of the switch 87, there is a sawing depth switch that adjusts the length of the grain culm that enters the threshing device 15, that is, the sawing depth. The saw depth switch may be, for example, a switch that selectively sets the saw depth to a first length (depth) and a second length (shallow) shorter than the first length.

The operation panel 18 is provided with a swivel mode switch. The swivel mode switch is a dial switch for switching the swivel control mode between soft swivel mode, brake swivel mode and spin swivel mode, and its range of motion includes soft swivel mode, brake swivel mode and spin swivel mode. The soft position, brake position and spin position corresponding to each are set. The swivel mode switch has a knob that is pinched and rotated by the operator's finger, and its position is switched by the rotation operation of the knob, and signals corresponding to each position of the soft position, the brake position, and the spin position are output. Output.

Further, the traveling control ECU 83 includes a current sensor 88 that outputs a detection signal corresponding to the value of the current supplied to the pressure control valves 61 and 63 included in the HST 31, and a pump diagonal plate of the hydraulic pump 41 included in the HST 31. Is connected to a pump sloping plate position sensor 89 that outputs a detection signal according to the position (inclination angle from the reference position), and the detection signals thereof are input.

The main ECU 81 receives information acquired from detection signals of various sensors by each ECU for individual specific control, and transmits commands and information required for control by each of these ECUs to each ECU. For example, the main ECU 81 receives the engine start permission transmitted from the travel control ECU 83, and transmits a command for starting the engine 32 to the engine ECU 82. Further, the main ECU 81 holds adjustment data for adjusting the detection values acquired from the detection signals of the main speed change lever sensor 85, the steering lever sensor 86, and the current sensor 88 connected to the travel control ECU 83. The adjustment data is transmitted to the travel control ECU 83.

The travel control ECU 83 includes information acquired from each detection signal of the main shift lever sensor 85, steering lever sensor 86, current sensor 88, and pump swash plate position sensor 89, information acquired from signals input from the switch 87, and In addition, the pressure control valves 61 and 63, the low-speed switching valve 73, the high-speed switching valve 74 and the turning mechanism included in the engine 32 and the HST 31 are used to control the traveling and turning of the machine body 11 based on the information input from the main ECU 81. It controls the valve for switching the engagement / disengagement of each clutch provided in.

<Running control>
The travel of the machine body 11 is controlled by the travel control ECU 83. In this travel control, the position of the main shift lever 21 is acquired from the detection signal of the main shift lever sensor 85.

When the position of the main speed change lever 21 is the stop position, the opening degree of each of them is adjusted by controlling the current supplied to the pressure control valve 61 on the forward side and the pressure control valve 63 on the reverse side of the HST 31, and the hydraulic pressure is increased. The position of the pump swash plate of the pump 41 is set to the position of the inclination angle of 90 °. As a result, the hydraulic oil is not discharged from the hydraulic pump 41, so that the hydraulic motor 42 does not rotate and power is not output from the HST 31. Therefore, the traveling device 12 does not operate and the machine body 11 is stopped.

When the main speed change lever 21 is tilted forward from the stop position, the pressure control valve 61 on the forward side moves to the first pressure chamber 62 of the servo cylinder 58 by controlling the current supplied to the pressure control valves 61 and 63 of the HST 31. The hydraulic pressure supplied is made larger than the hydraulic pressure supplied from the pressure control valve 63 on the reverse side to the second pressure chamber 64. As a result, a differential pressure is generated between the first pressure chamber 62 and the second pressure chamber 64, and the differential pressure causes the position of the pump swash plate of the hydraulic pump 41 to be a position where the inclination angle is less than 90 °. As a result, hydraulic oil is discharged from the hydraulic pump 41, the hydraulic motor 42 receives the hydraulic oil and rotates, and power in the forward direction is output from the HST 31. At this time, if the state of the turning mechanism is a state of transmitting constant speed power to the left and right traveling devices 12, the left and right traveling devices 12 rotate at a constant speed in the forward direction, so that the machine body 11 moves straight forward. ..

When the main speed change lever 21 is tilted rearward from the stop position, it is supplied from the reverse pressure control valve 63 to the second pressure chamber 64 by controlling the current supplied to the pressure control valves 61 and 63 of the HST 31. The hydraulic pressure is made larger than the hydraulic pressure supplied from the pressure control valve 61 on the forward side to the first pressure chamber 62 of the servo cylinder 58. As a result, a differential pressure is generated between the first pressure chamber 62 and the second pressure chamber 64, and the differential pressure causes the position of the pump swash plate of the hydraulic pump 41 to be larger than the inclination angle of 90 °. As a result, the hydraulic oil is discharged from the hydraulic pump 41 in the direction opposite to that at the time of forward movement, the hydraulic motor 42 receives the hydraulic oil and rotates in the direction opposite to that at the time of forward movement, and power in the reverse direction is output from the HST 31. At this time, if the state of the turning mechanism is a state of transmitting constant velocity power to the left and right traveling devices 12, the reverse power output from the HST 31 is transmitted to the traveling device 12, and the left and right traveling devices 12 are transmitted. Rotates at a constant speed in the reverse direction, so that the aircraft 11 moves straight backward.

When the tilt angle of the pump diagonal plate of the hydraulic pump 41 is changed by controlling the current supplied to the pressure control valves 61 and 63 during forward or backward movement, the amount of hydraulic oil discharged from the hydraulic pump 41 changes. , The rotation speed of the hydraulic motor 42 changes. Therefore, by adjusting the tilt angle of the pump swash plate of the hydraulic pump 41 according to the amount of tilt from the stop position of the main shift lever 21, the forward and reverse speeds of the machine body 11 can be changed steplessly. ..

Further, by switching the low-speed switching valve 73 and the high-speed switching valve 74 on / off, it is possible to switch between a high-speed stage in which the rotation speed of the hydraulic motor 42 is relatively large and a low-speed stage in which the rotation speed is relatively small. .. Therefore, the forward and reverse speeds of the airframe 11 can be changed by switching between the high-speed stage and the low-speed stage. It is preferable that the operation panel 18 of the driver's cab 13 is provided with an auxiliary shift lever (not shown), and the operation of the auxiliary shift lever is instructed to switch between the high-speed stage and the low-speed stage.

<Turning control>
When the steering lever 22 is tilted from the central straight position to the left or right turning position during straight-ahead (forward / backward) running of the machine body 11, the running control ECU 83 controls turning to turn the machine body 11. It will be started.

In the turning control, it is determined from the output signal of the turning mode switch whether the position of the turning mode switch is the soft position, the brake position, or the spin position.

When the position of the swivel mode switch is the soft position, the valve for switching the engagement / disengagement of each clutch provided in the swivel mechanism is controlled, and the swivel mechanism transmits constant speed power to the left and right traveling devices 12. The state switches to a state in which a power lower than the power transmitted to one of the left and right traveling devices 12 is transmitted to the other.

When the position of the swivel mode switch is the brake position, the valve for switching the engagement / disengagement of each clutch provided in the swivel mechanism is controlled, and the swivel mechanism transmits constant speed power to the left and right traveling devices 12. The state is switched to a state in which power is transmitted to only one of the left and right traveling devices 12.

When the position of the swivel mode switch is the spin position, the valve for switching the engagement / disengagement of each clutch provided in the swivel mechanism is controlled, and the swivel mechanism transmits constant speed power to the left and right traveling devices 12. The state is switched to a state in which the power transmitted to one of the left and right traveling devices 12 and the power in the opposite direction are transmitted to the other.

<Specific configuration for driving control>
FIG. 4 is a block diagram showing a specific configuration for traveling control.

The travel control ECU 83 has target diagonal plate position calculation unit 101, actual diagonal plate position calculation unit 102, deviation calculation unit 103, PI (Proportional-Integral) calculation unit 104, and FF (Proportional-Integral) calculation unit 104 as processing units for travel control. Feed forward) Control unit 105, Addition unit 106, Forward side current detection unit 107, Forward side average current calculation unit 108, Forward side deviation calculation unit 109, Forward side PI calculation unit 110, Forward side FF control unit 111, Forward side addition A unit 112, a reverse side current detection unit 113, a reverse side average current calculation unit 114, a reverse side deviation calculation unit 115, a reverse side PI calculation unit 116, a reverse side FF control unit 117, and a reverse side addition unit 118 are substantially provided. There is. Each processing unit is realized by software by program processing or by hardware such as a logic circuit.

The target swash plate position calculation unit 101 adjusts the detection value obtained by digitizing the detection signal of the main shift lever sensor 85 by using the adjustment data transmitted from the main ECU 81 to the travel control ECU 83, and detects after the adjustment. The value is set according to the position of the main shift lever 21. For example, due to variations in the assembly of the main shift lever sensor 85, the detected value of the main shift lever sensor 85 when the main shift lever 21 is in the neutral position (reference position) may deviate from the reference value according to the reference position. .. The adjustment data is data for adjusting the detection value of the main speed change lever sensor 85 in order to eliminate the deviation. The target swash plate position calculation unit 101 is a target swash plate position target of the hydraulic pump 41 according to the position of the main speed change lever 21 according to a predetermined calculation formula in a range of a preset maximum vehicle speed or less. Calculate the plate position. A map defining the relationship between the position of the main shift lever 21 and the target swash plate position is stored in the memory of the traveling control ECU 83, and the target swash plate position calculation unit 101 of the main shift lever 21 according to the map. The target swash plate position may be set according to the position.

The actual swashplate position calculation unit 102 adjusts the detection value obtained by digitizing the detection signal of the pump swashplate position sensor 89 by using the adjustment data transmitted from the main ECU 81 to the travel control ECU 83, and detects after the adjustment. The value is set according to the actual swash plate position, which is the actual position (tilt angle) of the pump swash plate of the hydraulic pump 41. For example, due to variations in the assembly of the pump swash plate position sensor 89, the detected value of the pump swash plate position sensor 89 when the pump swash plate of the hydraulic pump 41 is located at the reference position may deviate from the reference value according to the reference position. be. The adjustment data is data for adjusting the detected value of the pump swash plate position sensor 89 in order to eliminate the deviation.

The deviation calculation unit 103 subtracts the value according to the actual swash plate position calculated by the actual swash plate position calculation unit 102 from the value corresponding to the target swash plate position calculated by the target swash plate position calculation unit 101. , Calculate the swash plate position deviation, which is the deviation between the target swash plate position and the actual swash plate position.

The PI calculation unit 104 has a P control term obtained by multiplying the diagonal plate position deviation by a predetermined proportional gain (proportional operation) and an I obtained by multiplying the diagonal plate position deviation by a predetermined integrated gain (integral operation). By adding the control term, the target current value, which is the target of the current values supplied to the pressure control valves 61 and 63, is calculated.

The FF control unit 105 obtains, for example, a correction amount of the target current value according to the swash plate position deviation according to the map stored in the memory of the travel control ECU 83. For example, in the memory of the traveling control ECU 83, a map defining the relationship between the swash plate position deviation and the correction amount of the target current value is stored.

The addition unit 106 adds the target current value obtained by the PI calculation unit 104 and the correction amount of the target current value set by the FF control unit 105.

The forward-side current detection unit 107 detects the value of the current supplied to the forward-side pressure control valve 61 from the detection signal of the current sensor 88 provided in association with the forward-side pressure control valve 61.

The forward-side average current calculation unit 108 obtains a moving average of the current values detected by the forward-side current detection unit 107, and calculates the value obtained by this as an actual current value.

The forward side deviation calculation unit 109 subtracts the actual current value calculated by the forward side average current calculation unit 108 from the sum of the target current value output from the addition unit 106 and the correction amount thereof, so that the target current value And the current value deviation, which is the deviation between the added value of the correction amount and the actual current value, is calculated.

The forward side PI calculation unit 110 has a P control term obtained by multiplying the current value deviation by a predetermined proportional gain (proportional operation) and an I obtained by multiplying the current value deviation by a predetermined integrated gain (integral operation). By adding the control term, the duty of the chopper control for controlling the current supplied to the pressure control valve 61 is calculated.

The forward side FF control unit 111 obtains a duty correction amount according to the current value deviation, for example, according to a map stored in the memory of the travel control ECU 83. For example, the memory of the travel control ECU 83 stores a map that defines the relationship between the current value deviation and the duty correction amount.

The forward side addition unit 112 adds the duty obtained by the forward side PI calculation unit 110 and the duty adjustment amount set by the forward side FF control unit 111. Then, the current supplied to the pressure control valve 61 on the forward side is chopper controlled with a duty corresponding to the added value.

The reverse side current detection unit 113 detects the value of the current supplied to the reverse side pressure control valve 61 from the detection signal of the current sensor 88 provided in association with the reverse side pressure control valve 61.

The reverse side average current calculation unit 114 obtains a moving average of the current values detected by the reverse side current detection unit 113, and calculates the value obtained by this as the actual current value.

The reverse side deviation calculation unit 115 subtracts the actual current value calculated by the reverse side average current calculation unit 114 from the sum of the target current value output from the addition unit 106 and the correction amount thereof, and thereby the target current value. And the current value deviation, which is the deviation between the added value of the correction amount and the actual current value, is calculated.

The reverse side PI calculation unit 116 has a P control term obtained by multiplying the current value deviation by a predetermined proportional gain (proportional operation) and an I obtained by multiplying the current value deviation by a predetermined integrated gain (integral operation). By adding the control term, the duty of the chopper control for controlling the current supplied to the pressure control valve 61 is calculated.

The reverse side FF control unit 117 obtains a duty correction amount according to the current value deviation, for example, according to a map stored in the memory of the travel control ECU 83. For example, the memory of the travel control ECU 83 stores a map that defines the relationship between the current value deviation and the duty correction amount.

The reverse side addition unit 118 adds the duty obtained by the reverse side PI calculation unit 116 and the duty adjustment amount set by the reverse side FF control unit 117. Then, the current supplied to the pressure control valve 63 on the reverse side is chopper controlled by the duty according to the added value.

With the above configuration, in the traveling control when each part of the combine 1 is operating normally, the pressure control valve 61 on the forward side and the pressure control valve 63 on the reverse side are set according to the change in the position of the main speed change lever 21. The supplied current is controlled, the position of the pump swash plate of the hydraulic pump 41 is adjusted, and the forward and reverse speeds of the machine body 11 change steplessly. This travel control is a travel control by a conventional method.

When an abnormality occurs in the combine 1 and the travel control information necessary for the travel control by the normal method cannot be acquired, the travel control ECU 83 executes the travel control by the degenerate method different from the normal method. The content of the traveling control by the degeneracy method differs depending on the type of abnormality occurring in the combine 1. The following are some specific examples of running control (degenerate control) by the degenerate method.

(1) Abnormality in which the position of the main speed change lever 21 cannot be acquired An abnormality such as a failure of the main speed change lever sensor 85 or a disconnection of the signal line connected to the main speed change lever sensor 85 causes the travel control ECU 83 to perform the main speed change lever. An abnormality in which the position of 21 cannot be obtained is considered. When this abnormality occurs, the travel control ECU 83 sets the switch 87 to be usable for instructing the machine body 11 to move forward and backward. Then, information to that effect is transmitted from the travel control ECU 83 to the main ECU 81, and the display of the meter panel 84 indicates that the switch 87 is used for instructing the forward / backward movement of the machine body 11 by the control of the main ECU 81. .. For example, a saw depth switch can be used to instruct the machine body 11 to move forward and backward, and by turning on the saw depth switch that sets the saw depth to the first length, it is possible to instruct the machine body 11 to move forward. By turning on the saw depth switch that sets the saw depth to the second length, it is possible to instruct the aircraft 11 to move backward.

In this case, when the saw depth switch for setting the saw depth to the first length is on, the target swash plate position calculation unit 101 calculates the target swash plate position according to the position of the main speed change lever 21. Instead, the target swash plate position, which is the target of the position of the pump swash plate of the hydraulic pump 41, is set to a fixed position on the forward side. On the other hand, when the saw depth switch for setting the saw depth to the second length is on, the target swash plate position calculation unit 101 does not calculate the target swash plate position according to the position of the main speed change lever 21. , The target swash plate position, which is the target of the position of the pump swash plate of the hydraulic pump 41, is set to a fixed position on the reverse side.

In such a case, the proportional gain and the integrated gain in each of the PI calculation unit 104, the forward side PI calculation unit 110, and the reverse side PI calculation unit 116 are set to be smaller than those in the normal control, for example, 0 (zero). To. As a result, the effect of the feedback control term in the traveling control becomes zero, and the servo mechanism 66 including the servo cylinder 58 and the pressure control valves 61 and 63 is feedforward controlled.

(2) Communication abnormality between the main ECU 81 and the travel control ECU 83 (No. 1).
When the travel control ECU 83 cannot acquire the adjustment data for detecting the position of the main shift lever 21 from the main ECU 81 due to a communication abnormality between the main ECU 81 and the travel control ECU 83, the target swash plate position calculation unit 101 performs the main shift. When the position of the lever 21 is acquired, the detection value acquired from the detection signal of the main shift lever sensor 85 is not adjusted, and the detected value is taken as the value corresponding to the position of the main shift lever 21 as it is.

Then, the proportional gain and the integrated gain in each of the PI calculation unit 104, the forward side PI calculation unit 110, and the reverse side PI calculation unit 116 are set to be smaller than those in the normal control, for example, 0 (zero). As a result, the effect of the feedback control term in the traveling control becomes zero, and the servo mechanism 66 including the servo cylinder 58 and the pressure control valves 61 and 63 is feedforward controlled.

(3) Communication abnormality between the main ECU 81 and the travel control ECU 83 (No. 2).
When the travel control ECU 83 cannot acquire adjustment data for calculating the value according to the actual swash plate position of the pump swash plate of the hydraulic pump 41 from the main ECU 81 due to a communication abnormality between the main ECU 81 and the travel control ECU 83. When the actual swashplate position calculation unit 102 calculates the value according to the actual swashplate position, the detected value obtained by digitizing the detection signal of the pump swashplate position sensor 89 is not adjusted, and the detected value is calculated. The value is taken as it is according to the position of the actual swash plate.

Then, the proportional gain and the integrated gain in each of the PI calculation unit 104, the forward side PI calculation unit 110, and the reverse side PI calculation unit 116 are set to be smaller than those in the normal control, for example, 0 (zero). As a result, the effect of the feedback control term in the traveling control becomes zero, and the servo mechanism 66 including the servo cylinder 58 and the pressure control valves 61 and 63 is feedforward controlled.

<Action effect>
As described above, the HST 31 is interposed between the engine 32 and the pair of left and right traveling devices 12. The HST 31 includes a hydraulic pump 41 driven by the power of the engine 32 and a hydraulic motor 42 driven by the hydraulic oil discharged from the hydraulic pump 41. The power of the hydraulic motor 42 is transmitted to the pair of left and right traveling devices 12.

At normal times, the HST 31 is controlled by a conventional method, and travel control information is used in the control. When an abnormality that cannot acquire driving control information occurs in combine 1, the control method of HST31 is switched from the normal method to the degenerate method that does not use the driving control information according to the occurrence of the abnormality, and then the degenerate method. HST31 is controlled by. As a result, even if an abnormality that cannot acquire travel control information occurs in the combine 1, the HST 31 can be degenerately operated, and power is transmitted from the HST 31 to the traveling device 12 to continue the traveling of the combine 1. can.

Therefore, when an abnormality occurs in which the combine 1 cannot acquire travel control information while crossing the railroad crossing, the combine 1 can cross the railroad crossing and the risk of the combine 1 getting stuck in the railroad crossing can be reduced. Further, when an abnormality occurs in which the combine 1 cannot acquire the travel control information while traveling on a slope, it is possible to prevent the power from being transmitted from the HST 31 to the traveling device 12, and the combine 1 is contrary to the intention of the driver. You can reduce the risk of going down a slope. Further, when an abnormality that the traveling control information cannot be acquired occurs in the combine 1 in the field, the combine 1 can be escaped from the field by self-propelling.

Therefore, it is possible to improve the safety and convenience when an abnormality in which the travel control information cannot be acquired occurs in the combine 1.

<Modification example>
Although one embodiment of the present invention has been described above, the present invention can also be implemented in other embodiments.

For example, in the above-described embodiment, combine 1 is taken as an example of a harvester, but the present invention is applied not only to combine 1 but also to a harvester for harvesting vegetables such as carrots, radishes, green soybeans, and cabbage. be able to.

In addition, various design changes can be made to the above-mentioned configuration within the scope of the matters described in the claims.

1: Combine (harvester)
12: Traveling device 15: Threshing device 21: Main shift lever (shift operation member)
31: HST (power transmission device)
32: Engine 41: Hydraulic pump 42: Hydraulic motor 66: Servo mechanism 81: Main ECU (control device)
83: Travel control ECU (travel control device, information acquisition means, normal control means, degeneration control means)
85: Main shift lever sensor (operation position detection means)
87: Switch (switch operation member)
89: Pump swash plate position sensor (swash plate position detection means)
102: Actual swash plate position calculation unit (swash plate position detecting means)

Claims (8)

A power transmission device including an engine, a pair of left and right traveling devices, a pump driven by the power of the engine, and a motor driven by a pressure oil discharged from the pump, and transmitting the power of the motor to the traveling device. , The shift operation member operated from the neutral position to one side to move the harvester forward, and operated from the neutral position to the other side to move the harvester backward, and the position of the shift operation member are detected. A traveling control device used in a harvester equipped with an operation position detecting means .
Information acquisition means for acquiring travel control information,
A normal control means for controlling the power transmission device by a normal method using the travel control information at a normal time when the information acquisition means can acquire the travel control information.
A degenerate control means that controls the power transmission device by a degenerate method that does not use the travel control information when the information acquisition means cannot acquire the travel control information .
Includes a switch operating member that can be switched between the first state and the second state .
The information acquisition means acquires the position information of the shift operation member as the travel control information based on the detection signal input from the operation position detection means.
When the position information of the shift operation member acquired by the information acquisition means is information indicating the position of the one side with respect to the neutral position, the normal control means is said to the traveling device from the power transmission device. When the power in the direction of advancing the harvester is output and the position information of the shift operating member acquired by the information acquisition means is information indicating the position of the other side with respect to the neutral position, the power transmission device. The power transmission device is controlled so that the power in the direction of moving the harvester backward is output to the traveling device.
The contraction control means has the power transmission when the switch operation member is in the first state at the time of abnormality in which the position information of the shift operation member cannot be acquired because the detection signal of the operation position detection means is not input. When the power is output from the device to the traveling device in the direction of advancing the harvester and the switch operating member is in the second state, the power in the direction of moving the harvester backward from the power transmission device to the traveling device is performed. A travel control device that controls the power transmission device so that The power transmission device further includes a servo mechanism for controlling the position of the pump swash plate of the pump.
The normal control means sets a target position of the pump swash plate according to the position of the shift operation member based on the position information of the shift operation member acquired by the information acquisition means, and the pump swash plate. The servo mechanism is feedback-controlled so that the position of the head matches the target position.
The degenerate control means sets the target position of the pump swash plate to a fixed position on the forward side when the switch operating member is in the first state, and when the switch operating member is in the second state. The traveling control device according to claim 1 , wherein the target position of the pump swash plate is set to a fixed position on the reverse side, and the servo mechanism is feed-forward controlled. The harvester is further equipped with a threshing device for threshing from the culm.
The switch operating member is a cutting depth switch according to claim 1 or 2 , wherein the length of the culm that enters the threshing device is selectively set to a first length and a second length shorter than the first length. The travel control device according to. The harvester further comprises a control device communicatively connected to the travel control device.
The power transmission device further includes a servo mechanism for controlling the position of the pump swash plate of the pump.
The control device holds operation position adjustment data for adjusting the position detected by the operation position detecting means so as to match the actual position of the shift operation member.
The information acquisition means acquires the position information of the shift operation member from the detection signal input from the operation position detection means by using the operation position adjustment data.
The degenerate control means corresponds to the position detected by the operation position detecting means at the time of an abnormality in which the position information of the shift operation member cannot be acquired because the information acquisition means cannot use the operation position adjustment data. The traveling control device according to any one of claims 1 to 3 , wherein a target position of the pump swash plate is set and the servo mechanism is feed-forward controlled. A power transmission device including an engine, a pair of left and right traveling devices, a pump driven by the power of the engine, and a motor driven by a pressure oil discharged from the pump, and transmitting the power of the motor to the traveling device. , The shift operation member operated from the neutral position to one side to move the harvester forward, and operated from the neutral position to the other side to move the harvester backward, and the position of the shift operation member are detected. A traveling control device used in a harvester equipped with an operation position detecting means.
Information acquisition means for acquiring travel control information,
A normal control means for controlling the power transmission device by a normal method using the travel control information at a normal time when the information acquisition means can acquire the travel control information.
The degeneracy control means for controlling the power transmission device by a degeneration method that does not use the travel control information when the information acquisition means cannot acquire the travel control information is included.
The harvester further comprises a control device communicatively connected to the travel control device.
The power transmission device further includes a servo mechanism for controlling the position of the pump swash plate of the pump.
The control device holds operation position adjustment data for adjusting the position detected by the operation position detecting means so as to match the actual position of the shift operation member.
The information acquisition means acquires the position information of the shift operation member from the detection signal input from the operation position detection means by using the operation position adjustment data.
When the position information of the shift operation member acquired by the information acquisition means is information indicating the position of the one side with respect to the neutral position, the normal control means is said to the traveling device from the power transmission device. When the power in the direction of advancing the harvester is output and the position information of the shift operating member acquired by the information acquisition means is information indicating the position of the other side with respect to the neutral position, the power transmission device. The power transmission device is controlled so that the power in the direction of moving the harvester backward is output to the traveling device.
The degenerate control means corresponds to the position detected by the operation position detecting means at the time of an abnormality in which the position information of the shift operation member cannot be acquired because the information acquisition means cannot use the operation position adjustment data. A travel control device that sets a target position of the pump swash plate and controls the servo mechanism in a feed-forward manner. The power transmission device further includes a servo mechanism for controlling the position of the pump swash plate of the pump.
The harvester is provided with a swash plate position detecting means for detecting the position of the pump swash plate.
The information acquisition means acquires the position information of the pump swash plate as the travel control information based on the detection signal input from the swash plate position detecting means.
The normal control means sets a target position of the pump swash plate based on the position information of the pump swash plate, and feedback-controls the servo mechanism so that the position of the pump swash plate matches the target position. death,
The travel control device according to any one of claims 1 to 5 , wherein the degenerate control means sets a target position of the pump swash plate and feed-forward controls the servo mechanism. A power transmission device including an engine, a pair of left and right traveling devices, a pump driven by the power of the engine, and a motor driven by a pressure oil discharged from the pump, and transmitting the power of the motor to the traveling device. It is a traveling control device used for a harvester equipped with
Information acquisition means for acquiring travel control information,
A normal control means for controlling the power transmission device by a normal method using the travel control information at a normal time when the information acquisition means can acquire the travel control information.
The degeneracy control means for controlling the power transmission device by a degeneration method that does not use the travel control information when the information acquisition means cannot acquire the travel control information is included.
The power transmission device further includes a servo mechanism for controlling the position of the pump swash plate of the pump.
The harvester is provided with a swash plate position detecting means for detecting the position of the pump swash plate.
The information acquisition means acquires the position information of the pump swash plate as the travel control information based on the detection signal input from the swash plate position detecting means.
The normal control means sets a target position of the pump swash plate based on the position information of the pump swash plate, and feedback-controls the servo mechanism so that the position of the pump swash plate matches the target position. death,
The degeneracy control means is a travel control device that sets a target position of the pump swash plate and feedforward-controls the servo mechanism. The harvester further comprises a control device communicatively connected to the travel control device.
The control device holds swash plate position adjustment data for adjusting the position detected by the swash plate position detecting means so as to match the actual position of the pump swash plate.
The information acquisition means acquires the position information of the pump swash plate from the detection signal input from the swash plate position detection means by using the swash plate position adjustment data.
The shrinkage control means is at a position detected by the swashplate position detecting means at the time of an abnormality in which the position information of the pump swashplate cannot be acquired because the information acquisition means cannot use the swashplate position adjusting data. The travel control device according to claim 6 or 7, wherein the target position of the pump swash plate is set based on the above, and the servo mechanism is feed-forward controlled.

Images