JP3838319B2 - Horizontal control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a horizontal control device, and more particularly to a horizontal control device such as an agricultural tractor or a riding management machine.
[0002]
[Prior art and problems to be solved by the invention]
In agricultural work vehicles such as agricultural tractors and riding management machines, a work machine such as a rotary is connected to the rear part of the machine via a link mechanism, and the rolling angle of the work machine relative to the machine is changed between the machine and the machine. There is known an actuator provided with a horizontal control device for automatically adjusting the rolling angle of the work implement by providing an inclination adjusting dial or the like for setting the rolling angle of the work implement on the machine body.
[0003]
In this horizontal control device, a sensor for detecting the rolling angle of the work machine is provided between the machine body and the work machine, and a tilt sensor for detecting the rolling angle of the machine body is provided in the machine body, and based on the detection value of each sensor. Calculate the rolling angle of the machine and the rolling angle of the work machine, and output a drive signal to the actuator to keep the rolling angle of the work machine horizontal regardless of the attitude of the machine, or the rolling angle of the machine and the work machine The actuator is controlled so as to be driven in order to maintain the rolling angle in parallel.
[0004]
In general, a tilt sensor is configured to suspend a pendulum that always faces in a vertical direction in a casing and detect a change in the angle of the right and left tilt of the casing attached to the fuselage with respect to the pendulum. For example, when the airframe starts to tilt in the lower right direction, the pendulum is relatively left on the left side. Therefore, the tilt sensor outputs a detection signal in the reverse direction immediately after the start of the tilt of the aircraft, and the response of detecting the tilt of the aircraft quickly is not good due to the time delay in the output of the detection signal.
[0005]
On the other hand, a method of providing a rolling angular velocity sensor for detecting the rolling angular velocity of the aircraft and calculating the rolling angle of the aircraft from the detection value of the rolling angular velocity sensor is also conceivable. However, various noises occur depending on traveling conditions such as the traveling speed of the aircraft, the hardness of the field, or the tire lug pattern, and the field conditions, and the detection signal of the rolling angular velocity sensor continuously changes in small increments. In particular, when running on sloping ground, the natural vibration of the fuselage increases due to the effect of the tire lug pattern, and if the horizontal control signal is output based on the detection signal of the rolling angular velocity sensor, the control error may increase. . In order to prevent this, an actuator capable of providing a variable speed with no response delay at all in synchronism with the output change of the rolling angular velocity sensor is required, which makes the configuration complicated and extremely expensive.
[0006]
Therefore, when the actuator provided between the machine and the work machine is driven and the rolling angle of the work machine is adjusted to perform horizontal control, the work machine is prevented from overshooting and response delay due to the rolling of the machine, and the tire The technical problem to be solved in order to perform accurate horizontal control corresponding to the noise of the rolling angular velocity sensor generated by the traveling conditions such as the lag pattern and the field conditions arises, and the present invention solves this problem. The purpose is to do.
[0007]
[Means for Solving the Problems]
The present invention has been proposed to achieve the above object, and a work machine is connected to the rear part of the machine body via a link mechanism, and the rolling angle of the work machine relative to the machine body is changed between the machine body and the work machine. A horizontal control device comprising an actuator and a means for detecting a rolling angle of the work machine relative to the machine body, a tilt sensor for detecting the rolling angle of the work machine on the machine body, and a tilt setting means for setting the rolling angle of the work machine The rolling machine is provided with rolling angular velocity detection means when the machine rolls, and the work machine according to the set value of the inclination setting means based on the detection value of the rolling angular velocity detection means and the detection value of the inclination sensor. When the tilt sensor detects a rolling angle greater than a certain value, the dead zone of the rolling angular velocity detection means is widened. When the detected value of the rolling angular velocity detection means is within said non sensitive zone is to provide a horizontal control apparatus characterized by being configured so as not to output the horizontal control signal based on the detection value of the rolling angular velocity detection means.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. 1 and 2 show a small tractor 10 as an example of a work vehicle, and a rotary work machine 12 is connected to the rear part of the machine body via a link mechanism 11. In the vicinity of the driver's seat 13, a position lever 15 that is a lifting / lowering position setting means for the work implement, a tilling depth adjustment dial 16 that is a working depth setting means for the work implement, and an inclination that is an inclination setting means for setting the rolling angle of the work implement An adjustment dial 17 and the like are provided. In addition, an inclination sensor 41 that is a means for detecting the rolling angle of the airframe and a means for detecting an angular velocity when the airframe is pitched are provided at the upper surface portion of the mission case 18 at a substantially central portion near the rear axle 19. A pitching angular velocity sensor 42 and a rolling angular velocity sensor 43 that is a means for detecting an angular velocity when the airframe rolls are housed integrally in a case 44.
[0009]
The link mechanism 11 includes a top link 20 and left and right lower links 21, 21, and the ends of the left and right lift arms 22, 22 and the lower links 21, 21 are connected by lift rods 23, 23 to drive the lift cylinder 24. By rotating the lift arm 22, the lower links 21, 21 move up and down via the lift rods 23, 23. Thus, the rotary working machine 12 moves up and down with the tip ends of the lower links 21 and 21 as the center of rotation.
[0010]
A lift arm angle sensor 25 is provided at the rotation base of the lift arm 22 as means for detecting the lift position of the work implement. The lift arm angle sensor 25 detects the rotation angle of the lift arm 22, and the controller 50. To calculate the elevation height of the rotary working machine 12. Further, a rear cover 27 is attached to the rear end portion of the main cover 26 of the rotary work machine 12 so as to be rotatable up and down, and a rotation angle of the rear cover 27 is detected by a rear cover sensor 28, and the controller 50 detects the rotation of the rotary work machine 12. Calculate tillage depth.
[0011]
On the other hand, as an actuator for changing the rolling angle of the rotary working machine 12 with respect to the machine body, a rolling cylinder 30 is provided in the middle of either the left or right lift rod 23, and the rolling cylinder 30 is expanded or contracted to increase or decrease the lift amount of the lower link 21. By changing the angle, the inclination of the rotary working machine 12 with respect to the machine body in the left-right direction can be changed.
[0012]
As a means for detecting the rolling angle of the rotary working machine 12 with respect to the machine body, a stroke sensor 31 is provided adjacent to the rolling cylinder 30, and the expansion / contraction length of the rolling cylinder 30 is detected by the stroke sensor 31. The rolling angle of the rotary working machine 12 is calculated by the controller 50, and the rolling cylinder 30 is driven according to the set value of the tilt adjusting dial 17 so that the horizontal working of the rotary working machine 12 can be performed.
[0013]
Here, a steering handle 32 which is a steering operation portion of the fuselage is provided in front of the driver's seat 13, and a forward / reverse switching lever 33 is provided in the vicinity of the steering handle 32, and the forward / backward switching lever 33 is operated. Thus, the driving force transmitted to the rear wheel 34 is reversed so that the traveling direction of the aircraft can be selected. In addition, a shift lever 35 is provided at the front lower portion of the driver's seat 13 and left and right brake pedals 36 and 36 that can be stepped independently are provided. The rotation operation of the steering handle 32 is transmitted to the steering device 37, and the front wheel 38 turns according to the steering amount. The steering amount of the front wheel 38 is detected by a front wheel break angle sensor 39.
[0014]
FIG. 3 is a block diagram of the control system. The working depth target value of the rotary working machine 12 is set by the working depth adjustment dial 16, and the lift position of the rotary working machine 12 is calculated by the detection signal of the lift arm angle sensor 25. At the same time, the rear cover sensor 28 detects the rotation angle of the rear cover 27 and calculates the working depth of the rotary working machine. Then, in order to maintain the rotation angle of the rear cover 27 at a predetermined angle corresponding to the working depth target value set by the working depth adjustment dial 16, to the raising solenoid or the lowering solenoid of the electromagnetic control valve that drives the lift cylinder 24. A control signal is output from the controller 50. Therefore, the lift arm 22 is turned up and down to move the rotary work machine 12 up and down, and the rear cover 27 is turned and the detection value of the rear cover sensor 28 is controlled to coincide with the tilling target value.
[0015]
On the other hand, the tilt adjustment dial 17 allows the operator to arbitrarily set the rolling angle of the rotary working machine 12. The rolling angle of the machine relative to the ground is detected by the tilt sensor 41, and the rolling angle of the rotary working machine 12 relative to the machine is detected by the stroke sensor 31. Accordingly, the rolling angle of the rotary working machine 12 with respect to the ground can be calculated from the detection values of both sensors, and the rolling cylinder 30 is driven to maintain the rolling angle of the working machine set by the tilt adjustment dial 17. A control signal is output from the controller 50 to the right-up solenoid or right-down solenoid of the electromagnetic control valve. Accordingly, the rolling cylinder 30 is expanded and contracted to change the rolling angle of the rotary working machine 12, and the detection value of the stroke sensor 31 is controlled to coincide with the target value of the horizontal control.
[0016]
Note that the pitching angular velocity sensor 42 and the rolling angular velocity sensor 43 are each of the vibration gyro type, and the structure is simple, precise, and inexpensive. However, a sensor other than the vibration gyro system may be used. The tilt sensor 41, the pitching angular velocity sensor 42, and the rolling angular velocity sensor 43 are provided at a substantially central portion near the rear axle 19 and closer to the center of gravity of the airframe than when installed on the front wheel 38 side. As a result, there is little vibration in the vertical direction and it is difficult to receive disturbances, and the measurement accuracy is improved. In addition, since all the three sensors are integrally stored in the case 44, the installation space becomes compact and the installation work can be simplified, for example, the power supply circuit can be shared.
[0017]
Further, a horizontal mode, a machine parallel mode, and an angle setting mode can be selected by the horizontal switch 45, and the horizontal switch 45 detects the relative inclination of the machine and the work machine and the inclination with respect to the ground. A target value for horizontal control is determined according to the set mode, and the rolling cylinder 30 is driven to adjust the inclination of the rotary working machine 12.
[0018]
For example, when the horizontal selector switch 45 is set to the horizontal mode, the inclination of the rotary work machine 12 with respect to the ground is calculated from the detection value of the inclination sensor 41 and the detection value of the stroke sensor 31, and this inclination is made zero. Set the target value for horizontal control. Then, a control signal is output from the controller 50 to the right-up solenoid or the right-down solenoid of the electromagnetic control valve that drives the rolling cylinder 30 so that the measured value of the stroke sensor 31 matches the target value. Therefore, control is performed so that the horizontal inclination of the rotary working machine 12 is horizontal regardless of the attitude of the machine body.
[0019]
On the other hand, when the horizontal changeover switch 45 is set to the aircraft parallel mode, the target value of the horizontal control is determined so that the lift amounts of the left and right lower links 21 are equal. Then, in order to drive the rolling cylinder 30 so that the measured value of the stroke sensor 31 coincides with this target value, a control signal is output from the controller 50 to the right raising solenoid or the right lowering solenoid. Therefore, the rotary working machine 12 is controlled so that the horizontal tilt is parallel to the tilt of the machine.
[0020]
When the horizontal changeover switch 45 is set to the angle setting mode, a target value for horizontal control is determined according to the set value of the tilt adjustment dial 17 arbitrarily set by the operator, and the measured value of the stroke sensor 31 is set to this value. In order to drive the rolling cylinder 30 so as to match the target value, a control signal is output from the controller 50 to the right-up solenoid or right-down solenoid. Therefore, the rotary working machine 12 is controlled to have an arbitrary inclination set.
[0021]
Here, noise caused by various vibrations is generated in the detection signal of the rolling angular velocity sensor 43 depending on the traveling condition and the field condition such as the traveling speed of the machine body, the hardness of the field, or the lug pattern of the tire. For example, as shown in FIG. 4, when the output signal of the rolling angular velocity sensor 43 changes from 0V to a maximum of 5V, the change in angular velocity when the aircraft rolls to the left appears upward in the graph, and the aircraft moves to the right. Assuming that the change in the angular velocity when rolling appears downward, the detection signal of the rolling angular velocity sensor 43 continuously changes in small increments due to the vibration noise of the airframe.
[0022]
Therefore, when performing horizontal control based on the rolling angular velocity, the peak value (upper peak value) of the right direction angular velocity and the peak value (lower end peak value) of the left direction angular velocity are continuously measured for a predetermined time, and each peak value is The moving average value is calculated, and the neutral position C of the rolling angular velocity sensor 43 is set from the moving average value of the rightward angular velocity peak value and the moving average value of the leftward angular velocity peak value. Then, as shown by the dotted line in FIG. 4, a dead zone U ₁ in a predetermined range (for example, ± ₁ V to 1.5 V with the neutral position as the center) is determined in advance with respect to the neutral position C, and the rolling angular velocity sensor 43 When the detected value is within the dead zone U ₁ , the rolling angle of the airframe is calculated from the detected value of the tilt sensor 41 in consideration of the angular velocity detection due to the natural vibration of the airframe, and the detected value of the tilt sensor 41 is detected. Is output to the electromagnetic control valve for the rolling cylinder 30 based on the “right-up” or “right-down” horizontal control signal. When a rolling angular velocity larger than the dead zone U ₁ is detected, a horizontal control signal is output to the electromagnetic control valve for the rolling cylinder 30 based on the detected value of the rolling angular velocity sensor 43.
[0023]
FIG. 5 shows a flowchart of horizontal control. When horizontal control is started, first, the state of various sensors, switches, dials and the like is read into the controller 50 (Step 100), and then the peak value of the rolling angular velocity sensor 43 is collected (Step 100). Step 110). Now, when vibration noise as shown in FIG. 4 is generated, the peak value of the angular velocity in the right direction (upper peak value) and the peak value of the left angular velocity (lower peak value) are continuously measured for a predetermined time, The moving average value of each peak value is calculated. Then, a region between the moving average value of the right-direction angular velocity peak value and the moving average value of the left-direction angular velocity peak value is set as a dead zone of the rolling angular velocity sensor 43 (Step 120).
[0024]
After setting the dead zone, if the detected value of the rolling angular velocity sensor 43 is within the dead zone (Step 130), it is regarded as noise caused by vibration and the rolling angle of the aircraft is calculated from the detected value of the tilt sensor 41. Then, based on the detected value of the tilt sensor 41, a horizontal control signal of “right-up” or “right-down” is output to the electromagnetic control valve for the rolling cylinder 30 (Step 140). On the other hand, when the detected value of the rolling angular velocity sensor 43 deviates from the dead zone and a large angular velocity is detected in the right or left direction, the value for the rolling cylinder 30 is determined based on the detected value of the rolling angular velocity sensor 43. A horizontal control signal is output to the electromagnetic control valve (Step 150).
[0025]
Here, when the tilt sensor 41 detects a tilt of a predetermined value or more, the width of the dead zone of the rolling angular velocity sensor 43 is increased in Step 120. This is because, as shown in FIG. 6, the lug pattern of the tire is provided with the lugs 60a and 60b inclined alternately from the center of the tread to the outside, and when the fuselage is in a horizontal state, the ground contact surface of the tire Becomes part A, and both lugs 60a and 60b are continuously in contact with the ground, so that the rolling angular velocity generated in the aircraft is small, but when the inclination of the aircraft increases, the ground contact surface of the tire is the B or C portion. This is because one of the lugs 60a or 60b is intermittently grounded, and the rolling angular velocity is intermittently generated in the airframe.
[0026]
Thus, when the tilt sensor 41 detects a tilt greater than a predetermined value and determines that the tilt of the airframe is large, the dead zone U ₁ of the rolling angular velocity sensor 43 is set as shown by the two-dot chain line in FIG. By expanding to a new dead zone U ₂ , stable horizontal control can be performed. The new dead zone U ₂ may be set so as to expand stepwise according to the inclination angle of the aircraft, or may be set so as to increase steplessly in proportion to the inclination angle of the aircraft.
[0027]
When the horizontal control output based on the detection value of the rolling angular velocity sensor 43 is stopped and the control is shifted to the horizontal control based on the tilt sensor 41, the detection value of the tilt sensor 41 is within a predetermined range within a predetermined time. Only the horizontal control output based on the tilt sensor 41 is started. This is because the horizontal control based on the tilt sensor 41 is performed after the change in the tilt of the airframe becomes gentle after the rolling angular velocity disappears.
[0028]
If the rolling angular velocity of the aircraft detected by the rolling angular velocity sensor 43 is ω and the detection time is T, the rolling angle θ of the aircraft is expressed by the following equation.
[0029]
θ = ω × T
The rolling angle of the rotary working machine 12 is calculated from the rolling angle θ of the machine body obtained by the above equation and the detected value of the stroke sensor 31, and the electromagnetic control valve for the rolling cylinder is operated according to the set value of the tilt adjustment dial 17. Outputs horizontal control signal. Thus, for noise inevitably generated due to traveling conditions, farm conditions, etc., a horizontal control signal based on the rolling angular velocity sensor 43 is not output as a dead zone. Therefore, unnecessary output can be eliminated, and responsive horizontal control can be performed at low cost.
[0030]
Here, when a large rolling angular velocity is detected, even if a horizontal control signal is output based on this, the target horizontal posture may not be corrected due to the relationship of the operating speed of the rolling cylinder 30. In order to prevent this, a delay is applied to the stop of the horizontal control output.
[0031]
For example, as shown in FIG. 7, a threshold value is set at a position of a constant value ± αV centered on the neutral position C beyond the dead zone U of the rolling angular velocity sensor 43, and the detected value of the rolling angular velocity sensor 43 is the dead zone. When the aircraft rolls to the right beyond U, and there is a request to output a “right-down” horizontal control signal (time point t ₁ ), the aircraft rolls further to the right and this rolling angular velocity is When the threshold value (+ αV) is exceeded (time point t ₂ ), the time T ₁ while the constant value + αV is exceeded is measured (time point t _{2 to} t ₃ ), and this rolling angular velocity is the threshold value (+ αV). ) During the time T ₁ (time t _{3 to} t ₄ ) from when it becomes below, even if the rolling angular velocity decreases and enters the dead zone U, the “right-down” horizontal control signal is not stopped. Elongation of rolling cylinder 30 To continue the dynamic.
[0032]
Similarly, when the detection value of the rolling angular velocity sensor 43 exceeds the dead zone U and there is a request to output a “right-up” horizontal control signal (time point t ₅ ), the rolling angular velocity exceeds the threshold value (−αV). (Time t ₆ ), the time T ₂ during which the constant value −αV is exceeded is measured (time t _{6 to} t ₇ ), and the rolling angular velocity becomes equal to or less than the threshold value (−αV). From time to time T ₂ (time t _{7 to} t ₈ ), even if the rolling angular velocity decreases and enters the dead zone U, the horizontal control signal “upward to the right” does not stop and the rolling cylinder 30 contracts. Continue driving.
[0033]
When the rolling cylinder 30 is a single rod type, the pressure receiving area of the piston is different between the expansion side and the contraction side, so that a difference occurs in the operation speed, and the contraction speed becomes faster than the expansion speed. The rolling cylinder 30 used in the small tractor described in the present embodiment has an extension speed of about 2/3 with respect to the contraction speed.
[0034]
Therefore, as shown in the lowermost stage of FIG. 7 (corrected right-up output), when the horizontal control signal of “right-up” is output and the rolling cylinder 30 is contracted, the output stop delay time is set to 2/2 of T2 described above. 3, the rolling angular velocity is reduced and the dead zone U is reduced during the time T ₂ × (2/3) from the time when the rolling angular velocity becomes equal to or less than the threshold value (−αV) (time point t _{7 to} t ₉ ). Even if entered, the contraction drive of the rolling cylinder 30 is continued without stopping the “right-up” horizontal control signal. Thus, the operation amount of the cylinder can be made the same on the expansion side and the contraction side of the rolling cylinder 30.
[0035]
On the other hand, as shown in FIG. 8, the time T ₃ while the constant value + αV is exceeded is measured (time points t _{11 to} t ₁₂ ), and the rolling angular velocity becomes equal to or less than the threshold value (+ αV). _{When the} output stop delay is performed during ₃ (time t _{12 to} t ₁₃ ) and the rolling angular velocity exceeds the reverse threshold (−αV) (time t ₁₄ ), the output stop delay It is necessary to prevent the work machine from overshooting by subtracting the time. Subtraction of the output stop delay is half of the difference between T4 of the time t ₁₃ and t _14. Thereby, the output stop delay of the “lower right” horizontal control signal is subtracted at time T ₅ from time t ₁₂ to time t ₁₅ .
[0036]
Since the degree of inclination with respect to the amount of expansion / contraction of the rolling cylinder 30 varies depending on the size of the mounting width of the rotary work machine 12, the tractor 10 is provided with a mounting width switching device (not shown). Accordingly, when the mounting width switching device is switched, it is natural to change the output stop delay time of the horizontal control signal described above.
[0037]
Here, when the aircraft turns during the horizontal control based on the detection value of the rolling angular velocity sensor 43, a command signal is output from the controller 50 to the lift solenoid of the lift cylinder electromagnetic control valve to raise the rotary work machine 12 to a predetermined height. Raise it. Alternatively, even when the machine is traveling straight ahead, the rotary work machine 12 is raised to a predetermined height by a manual operation when going out of the work area or when moving the machine backward. At this time, if the rolling angular velocity sensor 43 detects the angular velocity due to the vibration of the airframe and outputs a horizontal control signal, the work implement may be rattled and the feeling of operation will be deteriorated. The output of the horizontal control signal based on the angular velocity is prohibited, and when the turning operation or the reverse operation is finished and the rotary work machine 12 is lowered, the horizontal control signal based on the rolling angular velocity is output again.
[0038]
For example, as shown in FIG. 9, when the detection value of the lift arm angle sensor 25 becomes a certain value or more during horizontal control based on the detection value of the rolling angular velocity sensor 43 (Step 200), the rotary work machine 12 rises. Since it is in operation or stopped at the ascending position, the output of the horizontal control signal based on the rolling angular velocity is prohibited (Step 210). Therefore, unnecessary horizontal control output is not performed while the work implement is raised, and the play of the work implement can be eliminated.
[0039]
When the rotary work machine 12 is lowered after the turning operation or the reverse operation is finished, a horizontal control signal based on the rolling angular velocity is not immediately output, but a weight for a predetermined time (about 2 seconds from the lowering operation) is applied. (Step230). During this time, the control signal is output by switching to horizontal control based on the detection value of the tilt sensor 41 (Step 240). Even if a rotary angular velocity occurs due to the work implement grounding or the like, a horizontal control signal based on the rolling angular velocity is not output, so that erroneous control can be prevented. After a predetermined time has elapsed, output of the horizontal control signal based on the rolling angular velocity is resumed (Step 250).
[0040]
It should be noted that the present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified one.
[0041]
【The invention's effect】
In the present invention, as described in detail in the above embodiment, when performing horizontal control of the work implement based on the detection value of the airframe tilt sensor and the detection value of the rolling angular velocity of the airframe, the tilt sensor is equal to or greater than a certain value. When the rolling angle is detected, a horizontal control signal based on the rolling angular velocity is output as the dead zone even if the rolling angle velocity dead zone is widened and vibration noise due to the tire lug pattern increases due to the inclination of the fuselage. Since the horizontal control signal is output based on the detected value of the tilt sensor, the unnecessary output can be eliminated without using a special high-performance sensor or actuator. And horizontal control with good responsiveness can be performed. On the other hand, when a rolling angular velocity greater than the dead zone is detected, horizontal control based on the rolling angular velocity is performed, so that it is possible to perform accurate horizontal control by preventing overwork of the work implement and response delay.
[Brief description of the drawings]
The figure shows an embodiment of the present invention.
FIG. 1 is a side view of a tractor body and a rotary work machine.
FIG. 2 is a rear view of FIG. 1 in which illustration of a rear cover sensor and the like is omitted.
FIG. 3 is a block diagram of a control system.
FIG. 4 is a graph showing a detection signal of a rolling angular velocity sensor when there is noise.
FIG. 5 is a flowchart showing a control procedure of the horizontal control device.
FIG. 6 is a perspective view of a main part showing a lug pattern of a tire.
FIG. 7 is a graph showing an output stop delay when a large rolling angular velocity is detected.
FIG. 8 is a graph obtained by subtracting an output stop delay.
FIG. 9 is a flowchart showing a control procedure when a work implement lowering operation is performed during horizontal control at a rolling angular velocity.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Tractor 11 Link mechanism 12 Rotary work machine 17 Inclination adjustment dial 30 Rolling cylinder 31 Stroke sensor 41 Inclination sensor 43 Rolling angular velocity sensor 50 Controller

Claims (1)

A work machine is connected to the rear part of the machine body via a link mechanism, and an actuator for changing the rolling angle of the work machine relative to the machine body and means for detecting the rolling angle of the work machine relative to the machine body are provided between the machine body and the work machine. In a horizontal control device comprising an inclination sensor for detecting the rolling angle of the machine body and an inclination setting means for setting the rolling angle of the work machine, a rolling angular velocity detection means when the machine rolls on the machine body And adjusting the rolling angle of the work implement according to the set value of the tilt setting means based on the detection value of the rolling angular velocity detection means and the detection value of the tilt sensor, and the tilt sensor When the angle is detected, the dead zone of the rolling angular velocity detection means is widened, and the detection value of the rolling angular velocity detection means is within the dead zone. A horizontal control apparatus characterized by being configured so as not to output the horizontal control signal based on the detection value of the rolling angular velocity detection means.

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