JP4107590B2 - Rolling control device for work equipment - Google Patents

Description

  The present invention relates to an actuator for connecting a ground working device to a traveling machine body so that the ground working device can be rolled, and an actuator for rolling the ground working device with respect to the traveling machine body, and an inclination for detecting a right and left inclination angle of the traveling machine body or the ground working device. Based on a sensor, an angular velocity sensor that detects an angular velocity in a lateral tilt direction of the traveling machine body or the ground work device, and a left and right tilt angle of the ground work device is set to a set angle based on detection values of the tilt sensor and the angular speed sensor. The present invention relates to a rolling control device for a working machine comprising a rolling control means for controlling the operation of the actuator so as to be maintained.

  The rolling control device using the tilt sensor and the angular velocity sensor as described above can perform rolling control with higher responsiveness and higher accuracy than the rolling control device using only the tilt sensor. Due to the sensitivity of the other axis, the control accuracy may decrease during turning.

  In other words, the angular velocity sensor needs to be mounted so that its detection operation axis is parallel to the rolling axis (axial center in the longitudinal direction of the aircraft), but in actuality, the mounting error of the angular velocity sensor itself, Due to the difference in the amount of subsidence of the front and rear wheels, the difference in the degree of indentation of the tire, etc., it is impossible to mount the detection operating axis of the angular velocity sensor completely in parallel with the rolling axis. Even if the case is accurately attached in a predetermined posture, if there is an attachment error or a processing error of an element inside the case, the angular velocity sensor outputs also to the yawing operation or pitching operation of the traveling machine body.

  In this way, a phenomenon that is sensitive to rotation around another axis (in this case, yawing axis and pitching axis) perpendicular to the sensor mounting axis (in this case, the rolling axis), the so-called other axis sensitivity When it becomes conspicuous, for example, when the vehicle is turned 180 degrees at the edge in a reciprocating operation in a farm field, or when the traveling machine body is rotated while changing its orientation according to the field shape in a modified farm field, If the vehicle is turned rapidly or relatively rapidly, an unnecessary output is output from the angular velocity sensor due to the sensitivity of the other axis corresponding to the yawing operation of the traveling machine body, and the control accuracy is lowered.

Therefore, conventionally, when the turning of the traveling vehicle body is detected such that the turning angle of the steered wheel is equal to or larger than the set value, the rolling control means is controlled based on only the detected value of the tilt sensor. It comprised (for example, refer patent document 1).
JP 2000-342010 A

  By the way, when performing a scraping work or a lawn mowing work with a work machine, the traveling machine body may be turned 180 degrees while continuing such work. Increases the cutting angle. In other words, in the above-described conventional technique, at the time of 180-degree turning work, rolling control with high responsiveness and high accuracy using the angular velocity sensor cannot be performed.

  On the other hand, the factor that makes the sensitivity of the other axis of the angular velocity sensor noticeable during turning is the turning angular velocity, which is the relationship between the vehicle speed and the turning angle of the wheel so that the turning angular velocity = vehicle speed ÷ turning diameter. Therefore, as in the above-described prior art, there remains a question as to whether or not the turning traveling of the traveling vehicle body is detected as a criterion for determining whether or not to use the angular velocity sensor.

  SUMMARY OF THE INVENTION An object of the present invention is to make it possible to accurately perform rolling control with high responsiveness and high accuracy by appropriately setting a criterion for determining whether or not to use an angular velocity sensor.

  As means for solving the above problems, in the present invention, a ground work device is connected to a traveling machine body so as to be able to roll, and an actuator for rolling the ground work device with respect to the traveling machine body, the traveling machine body or the Based on a tilt sensor that detects a left / right tilt angle of the ground work device, an angular speed sensor that detects an angular velocity in a left / right tilt direction of the traveling machine body or the ground work device, and a detection value of the tilt sensor and the angular speed sensor, In a rolling control device for a working machine comprising a rolling control means for controlling the operation of the actuator so that the right and left tilt angle of the ground working device is maintained at a set angle, the traveling machine body is turned on each wheel during turning. The turning center is configured to converge to one point on the extension line of the fixed axle, and the traveling speed of the traveling machine body is set. A vehicle speed sensor to be output and a turning angle sensor for detecting a turning angle of the steered wheel, and based on the distance between the shaft and the wheel interval of the traveling machine body and the detected value of the turning angle sensor, A turning angular velocity calculation means for performing a calculation process for calculating a turning angular velocity generated during the turning traveling based on the turning diameter and a detection value of the vehicle speed sensor, and the turning angular velocity is set in advance. Determining means for determining whether or not the limit turning angular velocity has been exceeded, and when the turning means determines that the turning angular velocity has exceeded the limit turning angular velocity, the determination unit determines whether the turning angle speed exceeds the limit turning angular speed or not only based on the detected value of the tilt sensor. The rolling control means is configured to be controlled.

  In this configuration, the traveling machine body is configured based on the so-called Ackermann-Jantho system in which the turning center of each wheel is converged to one point on the extension line of the fixed axle at the time of turning. The relational expression of turning radius r = W (distance between axes) ÷ tan θs (distance angle) + H (distance between wheels) ÷ 2 based on the distance W between the wheels, the wheel interval H, and the detected value θs of the angle sensor. Thus, it is possible to easily calculate the turning radius r when turning.

  Further, the turning angular velocity ω is ω (turning angular velocity) = v (vehicle speed) ÷ r (turning diameter), and the turning angle is calculated from the relational expression r and the detection value v of the vehicle speed sensor as described above. The angular velocity ω can be easily calculated, and an appropriate usable region of the angular velocity sensor can be obtained by comparing the calculated turning angular velocity ω with a limit turning angular velocity ωm set in advance based on the usage standard of the angular velocity sensor.

  Then, when the usable area of the angular velocity sensor obtained in this way is compared with the usable area of the angular velocity sensor obtained simply by setting the steering wheel turning angle, the steering wheel turning angle is large. However, there are areas where the angular velocity sensor can be used for low speed traveling, and where it is desirable to avoid using the angular velocity sensor for high speed traveling even when the steering wheel has a small turning angle. Can be recognized.

  In other words, if the use of the angular velocity sensor is determined based on the turning angular velocity generated during turning, even if the traveling body is turned 180 degrees while continuing the work in the cutting work or the lawn mowing work, For low-speed driving, it is possible to perform rolling control with high responsiveness and high accuracy using an inclination sensor and an angular velocity sensor, and because the turning angle of the steering wheel is small while driving at high speed, It is possible to avoid performing rolling control with low accuracy based on the output of the angular velocity sensor that is greatly influenced by the axial sensitivity.

  Therefore, the use of the angular velocity sensor can be determined based on an appropriate judgment criterion based on the turning angular velocity at the time of turning, which is a factor that makes the other-axis sensitivity of the angular velocity sensor at the time of turning running conspicuous. Therefore, it is possible to accurately perform rolling control with high accuracy and at the same time avoid precisely performing rolling control with low accuracy, and as a result, it is possible to improve the evenness during the turning operation.

  As one of means for making the present invention more suitable, a ratio between the measured turning angular speed and the calculated turning angular speed at the time of the test turning travel is provided as a correction coefficient in the calculation processing of the turning angular speed calculating means. .

  According to this configuration, it is possible to calculate a more accurate turning angular velocity in consideration of a decrease in the actual speed with respect to the detected value of the vehicle speed sensor due to wheel slip that occurs during traveling, thereby more accurately using the angular velocity sensor. Can be determined.

  Therefore, the use of the angular velocity sensor based on the appropriate judgment criteria based on the turning angular velocity during turning can be determined at a more appropriate turning angular velocity that takes into account the decrease in actual speed due to wheel slip. High-precision rolling control can be performed more accurately, and low-precision rolling control can be more accurately avoided. As a result, it is possible to further improve the levelness during the turning operation.

As a means for the present invention to more suitable, the traveling state of the vehicle body, comprising a running control means for switching the plurality of traveling condition of different turning diameters, a plurality of the traveling condition, the turning diameter A correction coefficient in the calculation process of the turning angular velocity calculating means corresponding to a small value for a large traveling state and a large value for a traveling state having a small turning diameter , The correction coefficient is selected according to the travel condition that the travel control means appears based on the determination information that enables the travel control means to determine the travel condition that appears.

  As the running state where the running control means appears, for example, a two-wheel drive state in which only the left and right rear wheels are driven, and a four-wheel drive in which the left and right front wheels are driven so that the peripheral speed thereof is equal to the peripheral speed of the rear wheels. State, front wheel acceleration state that drives the front wheel so that its peripheral speed is faster than the peripheral speed of the rear wheel, braking front wheel acceleration state that brakes the rear wheel inside the turn in this front wheel acceleration state, etc. For example, even if the steering wheel detected by the turning angle sensor has the same turning angle, the front wheel and the rear wheel have the same peripheral speed in the four-wheel drive state. The turning diameter becomes larger compared to the driving state, and in the front wheel acceleration state, the peripheral speed of the front wheel becomes faster than the peripheral speed of the rear wheel. In the acceleration state, brake the rear wheel inside the turn with the front wheel acceleration state. Et turning diameter is further reduced.

  In other words, even if the steering angle of the steered wheels is the same, depending on the running condition that appears during turning, the turning diameter varies and the turning angular speed that occurs during turning changes. The possible areas will also be different.

  Therefore, by taking the above-mentioned means, it is possible to select a correction coefficient in consideration of the traveling state that the traveling control means appears. By this, the traveling condition that the traveling control means appears is considered. An accurate turning angular velocity can be calculated, and the use of the angular velocity sensor can be more accurately determined.

  Therefore, the use of the angular velocity sensor based on the appropriate judgment criteria based on the turning angular velocity during turning traveling can be determined at a more appropriate turning angular velocity considering the traveling state that appears during turning work. Regardless of the state, it is possible to accurately perform highly accurate rolling control with high responsiveness and to accurately avoid performing rolling control with low accuracy, and as a result, it is possible to further improve flatness during turning operations. become.

  FIG. 1 shows an overall side view of the work machine, and FIG. 2 shows a rear part thereof. The work machine has a top link 2 and a pair of left and right lower links 3 at the rear part of a tractor 1 as a traveling machine body. The rotary plowing device 5 which is an example of a ground work apparatus is connected through a three-point link mechanism 4 composed of

  As shown in FIGS. 1 to 3, the tractor 1 has an engine 6 mounted on the front portion thereof and a pair of left and right front wheels 7 as steering wheels, and the left and right front wheels 7 are connected to the left and right front wheels 7 via a steering operation system. The boarding operation part 11 is formed with a steering wheel 8, a meter panel 9 for displaying information such as a vehicle speed, and a driver seat 10, and a pair of left and right rear wheels 12 and a pair of left and right lifts at the rear part. The arm 13 is configured to include a hydraulic single-acting lift cylinder 14 that swings and drives the left and right lift arms 13 in the vertical direction, and the left lift arm 13 is interposed via a lift rod 15. Are connected to the left lower link 3 and the right lift arm 13 is connected to the right lower link via a hydraulic double-acting rolling cylinder 16 which is an example of an actuator. It has been linked to the 3. In other words, the rotary tiller 5 is driven up and down by the operation of the lift cylinder 14, and the rotary tiller 5 is driven by the rolling cylinder 16.

  As shown in FIGS. 1, 4, and 5, the power from the engine 6 is transmitted to the transmission 20 incorporated in the transmission case 19 via the main clutch 18 incorporated in the clutch housing 17, and the transmission 20 Transmission from the left and right front wheels 7 is performed through a front wheel transmission system including a front wheel transmission 21 and a front wheel differential 22, and transmission from the transmission 20 to the left and right rear wheels 12 is performed by rear wheels. It is configured such that transmission from the transmission 20 to the rotary tiller 5 is performed via a work transmission system (not shown).

  The front wheel transmission 21 transmits the power after shifting by the transmission 20 to the left and right front wheels 7 via a standard clutch 24 formed of a hydraulic multi-plate clutch, a gear-type standard transmission mechanism 25, and the like. A standard four-wheel drive state in which the peripheral speed of the front wheel 7 and the peripheral speed of the rear wheel 12 are made equal, a speed increasing clutch 26 composed of a hydraulic multi-plate clutch, a gear speed increasing transmission mechanism 27, etc. To the left and right front wheels 7, the front wheel 7 is driven at a speed that is, for example, about twice as fast as the peripheral speed of the front wheel 7 is higher than the peripheral speed of the rear wheel 12. It is configured to be switchable to a two-wheel drive state in which transmission is not performed.

  The transmission case 19 is equipped with a pair of left and right side brakes 28 that are hydraulic and multi-plate type, and the left and right side brakes 28 correspond to a braking force proportional to the hydraulic pressure via corresponding left and right rear axles 29. It is configured to act on the rear wheel 12.

  As shown in FIG. 3, the tractor 1 is based on the Ackermann-Jantho method, and when turning, the turning angle θsa of the front wheel 7 inside the turning is larger than the turning angle θsb of the front wheel 7 outside the turning, The turning centers of the wheels 7 and 12 are configured to converge to one point on the extension line of the rear axle 29 which is a fixed axle, whereby the inter-axis distance W, the wheel interval H, and the cutting angle of the front wheel 7 are configured. From θs, a relational expression of turning radius r = W (distance between axes) ÷ tan θs (cut angle of front wheel 7) + H (wheel spacing) ÷ 2 can be derived from turning. That is, if the turning angle θs of the front wheel 7 is detected, the turning radius r during turning traveling can be calculated.

As shown in FIGS. 4 to 7, the tractor 1 is equipped with a first control device 30 composed of a microcomputer, and this first control device 30 is arranged in the lower right portion of the boarding operation unit 11. A pair of brake sensors 32 that detect the amount of depression of the corresponding left and right brake pedals 31 and an electromagnetic that detects the rotational speed of the gear 34 provided on the transmission shaft 33 ranging from the transmission 20 to the rear wheel differential 23 as the vehicle speed v. A vehicle speed sensor 35 comprising a pick-up rotation sensor, a turning angle sensor 36 comprising a rotary potentiometer that detects the amount of operation of the steering operation system as the turning angle θs of the front wheels 7, and a travel selection for selecting the travel mode of the tractor 1 based on the respective outputs of a switch 37 switches the flow conditions of the working fluid with respect to the left and right corresponding side brake 28 Brake control valve 38 of the pair, and, running control means 40 for controlling the operation of such a clutch control valve 39 for switching the flow state of the hydraulic oil is provided for the standard clutch 24 and the speed increasing clutch 26.

  The traveling modes selected by the traveling selection switch 37 in the tractor 1 include a two-wheel drive mode, a four-wheel drive mode, an automatic front wheel acceleration mode, and an automatic braking front wheel acceleration mode.

  When the two-wheel drive mode is selected by the travel selection switch 37, the travel control means 40 turns on the 2WD lamp 41 provided on the meter panel 9, and the standard regardless of the outputs of the vehicle speed sensor 35 and the turning angle sensor 36. The operation of the clutch control valve 39 is controlled so that the clutch 24 and the speed increasing clutch 26 are maintained in the non-transmission state, and a two-wheel drive state in which only the left and right rear wheels 12 are driven appears.

  When the four-wheel drive mode is selected by the travel selection switch 37, the 4WD lamp 42 provided on the meter panel 9 is turned on, and the standard clutch 24 is in a transmission state regardless of the outputs of the vehicle speed sensor 35 and the turning angle sensor 36. In addition, the operation of the clutch control valve 39 is controlled so that the speed-increasing clutch 26 is maintained in the non-transmission state so that the peripheral speeds of the left and right front wheels 7 and the left and right rear wheels 12 are equal. The four-wheel drive state to drive appears.

  When the automatic front wheel acceleration mode is selected by the travel selection switch 37, first, the acceleration lamp 43 provided in the meter panel 9 is turned on, and the cutting angle θs of the front wheel 7 is determined based on the output of the cutting angle sensor 36. When the turning angle θs is less than the set angle θso (for example, 35 degrees), the above-described four-wheel drive state appears regardless of the output of the vehicle speed sensor 35, and the turning angle θs is greater than or equal to the set angle θso. In some cases, the vehicle speed v is determined based on the output of the vehicle speed sensor 35, and the vehicle speed v is less than the first set speed (for example, 0.2 km / h) or the second set speed (for example, 5 km / h) or more. If the vehicle speed v is greater than or equal to the first set speed and less than the second set speed, the standard clutch 24 is in a non-transmission state and the speed increasing clutch 26 Is in the transmission state The front wheels that drive the left and right front wheels 7 and the left and right rear wheels 12 so that the peripheral speed of the front wheels 7 is higher than the peripheral speed of the rear wheels 12 by controlling the operation of the clutch control valve 39 so as to switch to The speed increase state appears.

  When the automatic braking front wheel acceleration mode is selected by the travel selection switch 37, first, the AD lamp 44 provided on the meter panel 9 is turned on, and the turning angle θs of the front wheel 7 is determined based on the output of the turning angle sensor 36. When the turning angle θs is less than the set angle θso (for example, 35 degrees), the above-described four-wheel drive state appears regardless of the output of the vehicle speed sensor 35, and the turning angle θs is greater than or equal to the set angle θso. In some cases, the vehicle speed v is determined based on the output of the vehicle speed sensor 35, and the vehicle speed v is less than the first set speed (for example, 0.2 km / h) or the second set speed (for example, 5 km / h) or more. If the vehicle speed v is greater than or equal to a third set speed (for example, 3.6 km / h) and less than the second set speed, the aforementioned front wheel acceleration state is manifested. Vehicle speed If v is greater than or equal to the first set speed and less than the third set speed, the aforementioned front wheel acceleration state appears and the side brake 28 for the rear wheel 12 on the inside of the turn is in a braking state. By controlling the operation of the braking control valve 38 to drive the left and right front wheels 7 and the left and right rear wheels 12 so that the peripheral speed of the front wheels 7 is higher than the peripheral speed of the rear wheels 12. The pre-braking wheel acceleration state for braking the wheel 12 is revealed.

  That is, in the automatic front wheel acceleration mode, the front wheel 7 is accelerated by increasing the speed of the front wheel 7 to reduce the turning diameter, and in the automatic braking front wheel acceleration mode, the front wheel 7 is accelerated. It is possible to automatically display the front wheel acceleration state in which the turning diameter is reduced and the front wheel acceleration state in which the front wheel 7 is accelerated and the rear wheel 12 inside the turning is braked to further reduce the turning diameter. While being able to improve the turning operability and turning performance on the ground, in both the automatic front wheel acceleration mode and the automatic braking front wheel acceleration mode, it is contrary to the operator's will in a low-speed traveling state below the first set speed. Thus, it is possible to prevent the small turning state from appearing and the sudden small turning state against the operator's will to appear in the high speed traveling state higher than the second set speed.

  Note that the traveling control means 40 outputs the output of each brake sensor 32 regardless of the traveling mode selected by the traveling selection switch 37 when one or both of the left and right brake pedals 31 are depressed. Based on the control, the operation of the corresponding brake control valve 38 is controlled, and the braking state of the left and right side brakes 28 corresponding to the amount of depression of the left and right brake pedals 31 appears.

As shown in FIG. 1, FIG. 2, FIG. 5 and FIG. 6, the tractor 1 is equipped with a second control device 45 comprising a microcomputer, and the second control device 45 selects a lifting control mode. The height setting device 48 composed of a rotary potentiometer that sets the target ground height of the rotary tiller 5 based on the swing operation amount of the lift selection switch 46, the lift lever 47, and the target tillage depth of the rotary tiller 5 are set. After the pressure leveling of the tilling depth setter 49 composed of a rotary potentiometer to be set, the lift arm sensor 50 composed of a rotary potentiometer for detecting the vertical swing angle of the lift arm 13, and the ground of the tillage by the rotary tiller 5 are suppressed. based on the outputs, such as tilling depth sensor 52 consisting of a rotary potentiometer for detecting the vertical swing angle of the cover 51, the lift Elevation control means 54 for controlling the operation of the lift control valve 53 for switching the flow state of the hydraulic oil for Linda 14 is provided.

  When the output of the lift selection switch 46 is “off”, the lift control means 54 determines that the output of the lift arm sensor 50 is the output of the height setter 48 based on the outputs of the height setter 48 and the lift arm sensor 50. The rotary tiller 5 is moved up and down to the set height by the height setting device 48 by controlling the operation of the lifting control valve 53 and operating the lift cylinder 14 so as to match (within the dead zone width). At the same time, position control is performed to maintain the height position.

  When the output of the elevating selection switch 46 is “ON”, the output of the tilling depth sensor 52 matches the output of the tilling depth setting device 49 based on the outputs of the tilling depth setting device 49 and the tilling depth sensor 52 (dead zone width). The state where the actual tilling depth is maintained at the target tilling depth by controlling the operation of the lifting control valve 53 and actuating the lift cylinder 14 so that the state of the tilling is maintained) Execute automatic tilling control that automatically raises and lowers.

If the swing operation from the output of the height setting device 48 to the upper limit position of the lifting lever 47 is recognized during the execution of the automatic tilling control, the rotary tiller 5 is raised with priority given to the position control. Thereafter, when the swing operation from the output of the height setting device 48 to the lower limit position of the lift lever 47 is recognized, the automatic tilling control is resumed and the actual tilling depth of the rotary tiller 5 is maintained at the target tilling depth. Automatically lift to state. In other words, when performing automatic heading depth control, for example, when turning headland turning to change direction at the side of a dredging, if the automatic heading depth control is temporarily stopped and the rotary tiller 5 is separated from the ground, it is lifted and lowered. When the lever 47 is swung to the upper limit position, or when the rotary tilling device 5 is grounded again after the headland turning traveling, etc., the automatic tilling control is resumed. By swinging to the lower limit position, these states can be easily switched and displayed.

  Further, during the execution of the automatic tilling control, if the output of the auto up switch 55 provided in the boarding operation unit 11 is “ON”, the cutting angle θs of the front wheel 7 is determined based on the output of the cutting angle sensor 36. When the cutting angle θs becomes equal to or greater than the set angle θso, the automatic tilling control is temporarily stopped and the lifting control valve 53 is operated so that the rotary tiller 5 is raised to a predetermined upper limit position. Then, when the cutting angle θs becomes less than the set angle θso, the automatic tilling control is resumed, and the rotary tiller 5 is automatically raised and lowered to a state where the actual tilling depth is maintained at the target tilling depth. In other words, by turning the output of the auto up switch 55 “on”, when the headland 7 turns headland more than the set angle θso, etc., the rotary tiller 5 is automatically activated at the start. The rotary tiller 5 can be automatically grounded at the end of the distance from the ground.

  As shown in FIGS. 1, 2, 5, and 6 to 10, the second control device 45 includes a rotary potentiometer that sets a target inclination angle θro in the horizontal direction with respect to the horizontal plane of the rotary tiller 5. An angular setter 56; a weight-type tilt sensor 57 that detects the left-right tilt angle θt of the tractor 1; a vibration gyro-type angular velocity sensor 58 that detects the angular velocity dθt / dt of the tractor 1 in the left-right tilt direction; The operation of the rolling control valve 60 for switching the flow state of the hydraulic oil with respect to the rolling cylinder 16 is controlled on the basis of the outputs of the stroke sensor 59 composed of a sliding potentiometer for detecting the operating length L of the rolling cylinder 16. By operating the rotary tiller 5, the horizontal inclination angle θr with respect to the horizontal plane is set to the target inclination. Rolling control means 61 for rolling drive is provided so as to maintain the angle Shitaro.

  That is, by operating the tilt angle setting device 56, the set angle in the left-right direction of the rotary tiller 5 can be arbitrarily changed.

  As shown in FIG. 8, the rolling control means 61 includes a right / left inclination angle calculating means 62 for calculating the left / right inclination angle θt of the tractor 1 based on the outputs of the inclination sensor 57 and the angular velocity sensor 58, and the tractor 1 has the right / left inclination angle θt. The cylinder length calculation means 63 for calculating the target cylinder length Lo of the rolling cylinder 16 necessary for setting the rotary tiller 5 to the target setting angle θro set by the inclination angle setting device 56, and the target Feedback comparing the cylinder length Lo and the length L of the rolling cylinder 16 output from the stroke sensor 59, and controlling the operation of the rolling control valve 60 so that the length L of the rolling cylinder 16 approaches the target cylinder length Lo. Cylinder operation control means 64 for performing control is provided.

  The calculation of the left / right tilt angle θt of the tractor 1 by the left / right tilt angle calculating means 62 is basically performed by integrating the output dθtj / dt of the angular velocity sensor 58 in the calculation processing section and calculating the error as the output θtr of the tilt sensor 57. This is done by correcting.

  That is, by using the angular velocity sensor 58 that is not affected by inertia and has excellent responsiveness, and the inclination sensor 57 that compensates for the drawbacks of the angular velocity sensor 58 that cannot detect the absolute inclination angle at the time of detection, the responsiveness is high and the accuracy is high. High rolling control can be performed.

  By the way, as a problem that the angular velocity sensor 58 has, in order to detect the angular velocity of the tractor 1 in the right-and-left tilt direction, the detection operation axis of the angular velocity sensor 58 is parallel to the rolling axis (axis centered in the longitudinal direction of the body). However, due to the mounting error and the difference in the amount of settlement of the front and rear wheels 7, 12, rotation around other axes (the yawing axis and the pitching axis) perpendicular to the rolling axis is also possible. There is a so-called other-axis sensitivity that is sensitive, and the factor that makes this other-axis sensitivity conspicuous during cornering is the turning angular velocity ω that occurs during cornering.

  In other words, if rolling control using the angular velocity sensor 58 is performed during a turning operation with a large turning angular velocity ω, rolling control with low accuracy is performed due to the influence of the sensitivity of the other axis, resulting in a decrease in flatness. .

  Therefore, the tractor 1 determines whether or not to perform rolling control using the angular velocity sensor 58 based on the turning angular velocity ω that is generated during turning.

  More specifically, as shown in FIG. 9 and FIG. 10, the left and right inclination angle calculation means 62 of the rolling control means 61 is transmitted from the Ackermann-Jantho method, which is a design index of the tractor 1, and the first control device 30. Based on the output value θs of the turning angle sensor 36, the turning radius r at the time of turning is calculated as follows: r (turning diameter) = W (distance between shafts) / tan θs (cutting angle of the front wheels 7) + H (wheel spacing) ÷ 2 based on the turning radius r obtained by the calculation and the output value v of the vehicle speed sensor 35 transmitted from the first control device 30, the turning angular velocity ω generated during the turning travel is expressed as ω A turning angular speed calculating means 65 that performs calculation processing calculated from (turning angular speed) = v (vehicle speed) ÷ r (turning diameter), and a determination for determining whether or not the turning angular speed ω exceeds a preset limit turning angular speed ωm. Means 66, and this If it is determined by the separate means 66 that the turning angular velocity ω has exceeded the limit turning angular velocity ωm, the rolling control means 61 performs the rolling control based only on the detected value θtr of the inclination sensor 57 without using the angular velocity sensor 58. Configured to do.

  The limit turning angular velocity ωm can be adjusted by a setting device (not shown) including a rotary potentiometer provided in the boarding operation unit 11.

  Then, when the usable area A1 of the angular velocity sensor 58 obtained by this is compared with the usable area A2 of the angular velocity sensor 58 simply obtained by setting the turning angle of the steered wheel 7, as shown in FIG. Even if the turning angle of the steered wheel 7 is large, the region A1a in which the angular velocity sensor 58 can be used if traveling at a low speed, or even if the turning angle θs of the steered wheel 7 is small, the vehicle can travel at high speed. If there is, it can be recognized that there is a region A2a where it is desirable to avoid the use of the angular velocity sensor 58.

  In other words, by determining the use of the angular velocity sensor 58 based on the turning angular velocity ω that is generated during turning traveling, even when the tractor 1 is turned 180 degrees while continuing the working state in a scraping operation or the like, the traveling at low speed is possible. If there is, it is possible to perform rolling control with good responsiveness and high accuracy using the inclination sensor 57 and the angular velocity sensor 58, and the front wheel 7 has a small cutting angle θs while being traveling at high speed, so that the other axis It is possible to avoid performing rolling control with low accuracy based on the output of the angular velocity sensor 58 having a large influence of sensitivity.

  By the way, the turning angular velocity ω obtained by the above calculation includes an error caused by slip of the wheels 7 and 12 generated during actual traveling. Therefore, the left / right inclination angle calculating means 62 is preliminarily provided with a ratio between the actual turning angular velocity actually measured in the test run on the field and the calculated turning angular velocity calculated at this time as a correction coefficient K1 for eliminating the error. In addition, the correction coefficient K1 is corrected by multiplying the turning angular velocity ω calculated during actual traveling by the first correcting means 67 for optimizing the turning angular speed ω calculated by the turning angular speed calculating means 65. .

In addition, as described above, the tractor 1 has two-wheel drive state, four-wheel drive state, front wheel acceleration state, and braking front wheel acceleration state as the traveling states that appear during turning. In the running state, even if the vehicle speed v detected by the vehicle speed sensor 35 and the turning angle θs of the front wheel 7 detected by the turning angle sensor 36 are the same, the turning radius r is different. For example, when the two-wheel drive state in which only the left and right rear wheels 12 are driven is used as a reference, the turning diameter is determined in the four-wheel drive state in which the left and right front wheels 7 are driven so that the peripheral speed thereof is equal to the peripheral speed of the rear wheel 12 In the front wheel acceleration state where r is increased and the front wheel 7 is driven so that its peripheral speed is higher than the peripheral speed of the rear wheel 12 , the turning radius r becomes small. In the brake pre-brake wheel acceleration state in which the brake 12 is braked, the turning radius r is further reduced. That is, the turning angular velocity ω obtained by the above calculation includes an error based on the difference in the running state that appears.

  Therefore, the left / right inclination angle calculating means 62 includes a value theoretically estimated according to the traveling state, or an actual turning angular velocity in each traveling state actually measured in the test traveling on the field, and each traveling state at this time. The ratio with the calculated turning angular velocity calculated correspondingly is provided in advance as correction coefficients K2a to K2d for eliminating the error, and the travel mode selected by the travel selection switch 37 transmitted from the first control device 30, Based on the output value v of the vehicle speed sensor 35 and the output value θs of the turning angle sensor 36, the currently running state is determined, and the correction coefficients K2a to K2d corresponding to the running state are calculated during actual driving. Second correction means 68 is further provided to further optimize the turning angular speed ω calculated by the turning angular speed calculation means 65 by performing correction by multiplying the angular speed ω.

  Since the relationship of the turning radius r in each traveling state is as described above, the relationship between the correction coefficients K2a to K2d in each traveling state is K2b (correction coefficient for four-wheel drive state) <K2a (two-wheel drive state). Correction coefficient) <K2c (correction coefficient for front wheel acceleration state) <K2d (correction coefficient for front wheel braking acceleration state). For example, when the correction coefficient K2a for the two-wheel driving state is set to “1”, four-wheel driving It is conceivable that the state correction coefficient K2b is “0.7”, the front wheel acceleration state correction coefficient K2c is “1.5”, and the brake front wheel acceleration state correction coefficient K2d = “1.8”.

  Then, the use of the angular velocity sensor 58 can be more accurately determined based on the turning angular velocity ω having a high prediction rate obtained by the above correction, and thereby, the rolling control with high responsiveness and high accuracy can be more accurately performed. Therefore, it is possible to more accurately avoid the rolling control with low accuracy, and as a result, it is possible to effectively improve the flatness during the turning operation.

[Another Example]
Other embodiments of the present invention will be listed below.
[1] The working machine may be a lawn mower configured by connecting a mower to the rear part of the tractor 1.

[2] As shown in FIG. 11, one control device 30 may include a travel control means 40, a lift control means 54, and a rolling control means 61.

[3] The rolling control means 61 appears based on the operation information when the travel control means 40 controls the operation of the brake control valve 38 and the operation information when the operation of the clutch control valve 39 is controlled. You may comprise so that the driving state in inside may be discriminate | determined.

Overall side view of work equipment Diagram showing the rear of the work equipment Diagram showing basic structure of tractor Schematic plan view showing the structure of the tractor Hydraulic circuit diagram Block diagram showing control configuration Diagram showing the correspondence between driving mode, vehicle speed and turning angle Block diagram showing the configuration of the rolling control means Block diagram showing the configuration of the right / left inclination angle calculation means Diagram showing usable area of angular velocity sensor The block diagram which shows the control structure in another Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Traveling machine body 5 Ground working apparatus 7 Steering wheel 12 Wheel 16 Actuator 29 Fixed axle 35 Vehicle speed sensor 36 Cutting angle sensor 40 Traveling control means 57 Inclination sensor 58 Angular speed sensor 61 Rolling control means 65 Turning angular velocity calculation means 66 Discriminating means H Wheel interval K1 correction coefficient K2a correction coefficient K2b correction coefficient K2c correction coefficient K2d correction coefficient W Axis distance dθtj / dt Angular speed r Turning radius v Traveling speed θs Cutting angle θt Left / right inclination angle θto Set angle θtr Left / right inclination angle ω Turning angular speed ωm Limiting turning angular speed

Claims (3)

A ground work device is connected to the traveling machine body so as to be able to roll, an actuator for rolling the ground work apparatus with respect to the traveling machine body, an inclination sensor for detecting a right and left inclination angle of the traveling machine body or the ground work device, An angular velocity sensor that detects an angular velocity in a left-right inclination direction of the traveling machine body or the ground work device, and a left-right inclination angle of the ground work device is maintained at a set angle based on detection values of the inclination sensor and the angular velocity sensor. A rolling control device for a work machine comprising a rolling control means for controlling the operation of the actuator.
The traveling machine body is configured such that the turning center of each wheel is converged to one point on the extension line of the fixed axle during the turning, and a vehicle speed sensor for detecting the traveling speed of the traveling machine body and a break of the steering wheel A cutting angle sensor for detecting a corner,
Based on the distance between the axis of the traveling machine body and the wheel interval, and the detection value of the cutting angle sensor, the turning diameter at the time of turning is calculated, and based on the turning diameter and the detection value of the vehicle speed sensor, A turning angular velocity calculating means for performing a calculation process for calculating a turning angular velocity generated during the turning, and a determining means for determining whether or not the turning angular speed exceeds a preset limit turning angular speed. A rolling control device for a working machine, wherein the rolling control means is controlled to operate only based on a detection value of the tilt sensor when it is determined that a turning angular velocity exceeds the limit turning angular velocity.   The rolling control device for a work machine according to claim 1, wherein a ratio between the measured turning angular velocity and the calculated turning angular velocity during the test turning travel is provided as a correction coefficient in the calculation processing of the turning angular velocity calculation means. Travel control means for switching the traveling state of the traveling machine body to a plurality of traveling states having different turning diameters ,
The turning angular velocity calculating means corresponding to the plurality of running states so as to have a small value for a running state with a large turning diameter and a large value for a running state with a small turning diameter. It has a correction coefficient in arithmetic processing ,
2. The configuration according to claim 1, wherein a correction coefficient is selected in accordance with the travel condition that the travel control unit appears based on discrimination information that enables the travel state that the travel control unit appears. The rolling control device for a work machine according to 2.

Images