JPH09238509A - Depth controller for rotary working machine - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To automatically prevent the rear cover of a rotary working machine from jumping up to prevent malfunction of the depth control device. A bracket 29 is fixed to a main cover 26 of a rotary working machine, and a base of a pair of left and right bell cranks 38 is pivotally attached to the bracket 29. Pressure rod 3
A cylindrical slider 35 is vertically movably inserted near the upper end of 0, and the tip of a bell crank 38 is connected to the slider 35. Further, the tip of the arm 40 pivotally attached to the stepping motor 39 and the other end of the bell crank 38 are connected by a rod 41. When the stepping motor 39 is driven to rotate the tip end of the bell crank 38 downward, the slider 35 is pressed downward and the spring 32 is compressed, so that the rear cover 27 is strongly held to the ground and the jumping is reduced. Regulated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a depth control device for a rotary working machine, and more particularly to a depth control device for a rotary working machine in which movement of a rear cover is restricted by a pressure rod.

[0002]

2. Description of the Related Art The depth control device for a rotary working machine of this type malfunctions when the rear cover vibrates up and down due to unevenness in the field. Therefore,
The rear cover is held down by a pressure rod etc. to prevent the rear cover from jumping up.

A device for detecting the vibration of the rear cover to change the sensitivity of the depth control is, for example, Shoukai 63-505.
The configurations of No. 04 and No. Sho 63-50505 are known. The former is designed so that the sensitivity of the control unit changes according to the vehicle speed of the tractor, and the suppression of the rear cover is manually adjusted. In the latter, the dead band width of the rear cover is adjustable by using an adjustment pin, and the operator operates the adjustment pin to change the dead band width.

As described above, when the rear cover jumps up during traveling work, it is necessary to manually move the operator down from the tractor each time, and the operability is not good.

Therefore, there arises a technical problem that should be solved in order to automatically prevent the rear cover from jumping up and prevent the depth control device from malfunctioning. The present invention aims to solve this problem. To aim.

[0006]

SUMMARY OF THE INVENTION The present invention has been proposed in order to achieve the above object, and is a rotary working machine connected to the rear part of a tractor, wherein a rear cover is pivoted on a rear end of a main cover. It is freely attached, the rotation of the rear cover is detected to control the working depth of the rotary working machine, and a bracket is fixed to the main cover to attach the upper part of the pressure rod, and the lower end of the pressure rod is attached to the rear cover. In a rotary working machine in which the movement of the rear cover is restricted by interposing a spring on the pressure rod, the expansion and contraction of the spring is restricted so that the movement amount of the rear cover can be automatically adjusted. The present invention provides a depth control device for a machine.

[0007]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a tractor 10, and a rotary working machine 12 is connected to a rear portion of the tractor 10 via a link mechanism 11. A control device 14 is provided near the driver's seat 13 of the tractor 10, and a position lever 15, a working depth setting dial 16, and a control device 14 are provided to the control device 14.
The rotary working machine 12 is provided with an inclination setting dial 17 and the like.
Set the plowing depth and the left and right tilt amounts. A slope sensor 18 and a vehicle speed sensor 19 are provided below the driver's seat 13.
Etc. are provided.

The link mechanism 11 is a three-point link system consisting of a top link 20 and left and right lower links 21. When the lift arm 22 is rotated, the lower link 21 moves up and down and the rotary working machine 12 moves up and down. To do.
The rotation angle of the lift arm 22 is determined by the lift arm sensor 23.
Detect with.

Further, a rolling cylinder 24 is provided on one or both of the left and right sides of the link mechanism 11, and the rolling cylinder 24 is expanded and contracted to change the lift amount of the lower link 21 between the left and right, whereby the rotary working machine 12 with respect to the tractor 10 is moved. Tilts to the left and right. The extension length of the rolling cylinder 24 is detected by a stroke sensor 25.

On the other hand, a rear cover 27 is rotatably attached to the rear end of the main cover 26 of the rotary working machine 12, the depth sensor 28 detects the rotation of the rear cover 27 and feeds it back to the control device 14, and a plowing depth setting dial. The rotary working machine 12 according to the working depth set in 16
Depth control. Further, the slope sensor 18 detects the tilt of the tractor 10 in the left-right direction, and the rolling control of the rotary working machine 12 is performed according to the tilt amount set by the tilt setting dial 17.

Here, due to the unevenness of the field, the rear cover 27
When the vibration occurs up and down, the detection value of the depth sensor 28 is disturbed and the depth control malfunctions. In order to prevent this, brackets 29 are provided at the left and right positions of the main cover 26.
, And the pressure rod 3 on each bracket 29.
The upper part of 0 is attached, and the lower end of the pressure rod 30 is connected to the bracket 31 of the rear cover 27. The movement of the rear cover 27 is regulated by interposing a spring 32 on the pressure rod 30, so that the rear cover 2
It prevents 7 from jumping up.

FIG. 2 shows the mounting portion of the pressure rod 30. Fixing rings 33 and 34 are fixed to the upper end and lower end of the pressure rod 30, respectively, and a cylindrical slider 35 near the upper end of the pressure rod 30. Insert vertically. A collar portion 35A is provided above and below the slider 35,
35B is fixedly provided, and pins 36 are provided on the left and right sides. Then, the above-mentioned spring 32 is interposed between the slider flange 35B and the lower fixing ring 34, and the spring 37 is interposed between the slider flange 35A and the upper fixing ring 33.

The bases of a pair of left and right bell cranks 38 are pivotally attached to the bracket 29 of the main cover 26, and both ends of the slider 35 are sandwiched between the ends of the bell crank 38 while the slider 35 and the bell crank 38 are sandwiched. The tip is connected by the pin 36. Further, a stepping motor 39 is fixedly installed on the main cover 26, and the tip of an arm 40 mounted on the motor shaft and the other end of the bell crank 38 are connected to the rod 4 by the rod 4.
Connect at 1.

When the stepping motor 39 is driven to rotate the arm 40 in the clockwise direction in the figure, the bell crank 38 is moved through the rod 41 as shown by the chain double-dashed line.
The other end is pulled, and the bell crank 38 rotates clockwise. Therefore, the slider 35 connected to the tip of the bell crank 38 is pressed downward, and the slider 35 moves downward along the pressure rod 30. For this reason, the spring 32 is compressed, the rear cover 27 is strongly held to the ground, and the rear cover 27 is regulated so that the rear cover 27 is prevented from jumping up.

Although not shown, a motor driven electrically or hydraulically is provided in place of the stepping motor 39, a rack gear is engaged with a pinion gear fitted to the motor shaft, and one end of the rack gear is bell crank 38. It may be connected to the other end of the. At that time, the rack gear is pushed back and forth by the drive of the motor, and the bell crank 38 is rotated steplessly to move the spring 3
Expansion and contraction of 2 is restricted. Alternatively, instead of the motor, the piston rod of the hydraulic cylinder may be connected to the other end of the bell crank 38, and the bell crank 38 may be continuously rotated by the expansion and contraction operation of the hydraulic cylinder.

FIG. 3 shows a block diagram of the attitude control system of the rotary working machine 12. The setting signals of the position lever 15, the working depth setting dial 16, the inclination setting dial 17 and the like are input to the control device 14. The control device 1 also detects detection signals from the slope sensor 18, the vehicle speed sensor 19, the lift arm sensor 23, the stroke sensor 25, the depth sensor 28, and the like.
4 is input.

In the control device 14, the tractor 1 is detected based on the detection signals of the slope sensor 18 and the stroke sensor 25.
0 and the rolling angle of the rotary working machine 12 are calculated, a drive signal is output to the rolling cylinder 24 according to the set value of the tilt setting dial 17, and the rolling control of the rotary working machine 12 is performed.

The height and the working depth of the rotary working machine 12 are calculated based on the detection signals of the lift arm sensor 23 and the depth sensor 28, and a drive signal is sent to the lift cylinder 42 according to the set value of the working depth setting dial 16. This is output and depth control of the rotary working machine 12 is performed.

Furthermore, due to the unevenness of the field, the rear cover 27
In order to prevent the rear cover 27 from vibrating up and down, a drive signal is output from the control device 14 to the stepping motor 39, and as described above, the expansion and contraction of the spring 32 interposed in the pressure rod 30 is restricted, and the rear cover 27 of the rear cover 27 is prevented. Adjust the amount of movement.

Next, the control for automatically adjusting the movement amount of the rear cover 27 will be described with reference to the flowchart of FIG. First, the setting signals of the levers and dials and the detection signals of the sensors are read into the control device 14 (step 100). As the vehicle speed of the tractor 10 increases, the rear cover 27 easily vibrates up and down, and the depth sensor 2
Since the detected value of 8 is disturbed, when the vehicle speed becomes 4 km / h or more (step 110), the process proceeds to step 150 to suppress the movement of the rear cover 27.

Further, when the PTO output becomes high speed, the rotary pawls rotate at high speed and the rear cover 27 easily vibrates up and down. Therefore, even when the PTO output becomes the second speed or higher (step 120), the rear cover 27 moves. To proceed to step 150.

Furthermore, when the field once cultivated is cultivated again, the tractor 10 rolls due to the unevenness of the field, and the detection value of the slope sensor 18 greatly changes. When the rolling of the tractor 10 becomes large, the rear cover 27
Easily vibrates up and down, so when the amount of change in the slope sensor value exceeds a predetermined range (step 13
0), Step 15 to prevent the movement of the rear cover 27
Go to 0.

Further, the depth sensor 2 may be formed by the unevenness of the field.
When the detection value of 8 largely changes and the depth sensor value deviates from the lower limit of the dead zone to the outside (step 140),
Since the rotary working machine 12 jumps up and the rear cover 27 hangs down, the rear cover 27 is likely to vibrate up and down due to its reaction. Therefore, the routine proceeds to step 150 in order to suppress the movement of the rear cover 27.

Then, in step 150, a drive signal is output from the control device 14 to the stepping motor 39, and as shown by the chain double-dashed line in FIG.
Is rotated to move the slider 35 downward. Therefore, the spring 32 is compressed, and the rear cover 27 is strongly pressed against the ground by the pressure rod 30, and the rear cover 27 is regulated so that the rear cover 27 is prevented from jumping up. This movement amount restraining process of the rear cover 27 is repeated until the lift arm 22 is raised to raise the rotary working machine 12 (step 160).

When the lift arm 22 is raised, a drive signal is output from the control device 14 to the stepping motor 39, and the stepping motor 3 is moved in the opposite direction to the above.
9 is driven, and the movement amount restraining process of the rear cover 27 ends. Therefore, at the position shown by the solid line in FIG.
8 returns, the compression of the spring 32 is released, and the pressure rod 30 is less pressed against the rear cover 27. In this way, the amount of movement of the rear cover 27 can be adjusted by restricting the expansion and contraction of the spring 32 and changing the pressure of the pressure rod 30 against the rear cover 27.

Here, if the detection accuracy of the slope sensor 18 is low, the rolling angle of the tractor 10 cannot be calculated accurately, which adversely affects the depth control and the rolling control of the rotary working machine 12. In particular, since silicon oil is sealed inside the slope sensor 18 and the change in the oil level is converted into a voltage to output a detection signal, when the rolling angle of the tractor 10 changes, it is caused by swinging back. If there is a change in the oil level, the slope sensor 18
The detected value of is disturbed and the rolling control malfunctions.

FIG. 5 shows a structure in which the slope sensor 18 is provided with a plurality of detecting portions. As shown in FIG. 5A, the detecting portion 50 is provided at the center of the slope sensor 18 and the right end of the slope sensor 18 is provided. The detection unit 51 is also provided in the vicinity.

For example, when the tractor 10 rolls upward to the right, the slope sensor 18 tilts upward to the right around the lower left end 52, as shown by the chain double-dashed line in FIG. At this time, since the right detection unit 51 is farther from the left lower end 52 than the central detection unit 50, the change in the oil level of the detection unit 51 is large. Therefore, as shown in the graph of FIG. 7B, the voltage V _{2 in} the detection unit 51 on the right is higher than the voltage V _{1 in} the detection unit 50 in the center.

On the other hand, when the tractor 10 rolls upward to the left, the change in the oil level of the central detecting portion 50 of the slope sensor 18 is large, so that the voltage is lower than the voltage V _{2 in} the right detecting portion 51. Voltage V _{1 at} the detection unit 50 of
Will be higher. In this way, if the detection signals from the plurality of detection units 50 and 51 are read into the control device 14 and the slope sensor value with the smaller voltage change is detected, even if there is a change in the oil level due to swingback, it is accurate. The rolling angle can be calculated.

Further, as shown in FIG. 6, two slope sensors 18a and 18b are arranged in parallel on the substrate 53, and the detection signals of the respective slope sensors 18a and 18b are read into the control device 14 to detect the slope sensor value. You may. For example, if the tractor 10 rolls to the left,
As shown in (a) of the figure, the substrate 53 is inclined to the left from the position shown by the solid line to the position shown by the chain double-dashed line centering on the lower right end 54.

When the rolling of the tractor 10 changes from the state of rising to the right to the state of rising to the right, the substrate 5
The movement of the left end of No. 3 is reversed, and its inclination returns from the position of the chain double-dashed line in the same figure (a) to the position of the solid line. Slope to the right from the position indicated by the solid line to the position indicated by the alternate long and two short dashes line.

Further, when the rolling of the tractor 10 changes from the state of rising to the right to the state of rising to the left, the substrate 53
The movement of the right end of is reversed, and its inclination returns from the position of the alternate long and two short dashes line in the same figure to the position of the alternate long and two short dashes line in the same figure. Thus, when the tractor 10 rolls to the left and right, the slope sensors 18a and 18b repeat the postures shown in FIGS.

FIG. 7 shows signals detected by the pair of slope sensors 18a and 18b when the tractor 10 rolls left and right, and the graph shows the slope sensor 18a.
Detection value, the graph shows the detection value of the slope sensor 18b,
The graph shows a combination of the detection values of both slope sensors 18a and 18b.

[0034] First, when the tractor 10 is rolled upward to the left, will change substantially in the same way the negative side with the graph (t ₁ ~t _2). Here, when the rolling changes from the upward rising state to the upward rising state, the graph temporarily changes to the positive side (t ₃ ), and the substrate 5
When the movement of the left end of 3 is reversed, the slope sensor 18
It can be seen that the oil surfaces of a and 18b fluctuate due to the shaking back.

At this time, looking at the graph, it is found that there is a large difference from the graph in the swing-back portion (t ₃ ), and the graph projects further to the plus side. That is,
In FIG. 6A, the slope sensor 18a far from the lower right end 54 is greatly disturbed. Therefore, in the swing-back control described later, the slope sensor value S _S (the side closer to the neutral value) with less swing-back (t in FIG. 7).
_In Fig. ₃ , rolling control is performed based on the value in the graph).

[0036] The unwag fits in a short time, as the tractor 10 is gradually rolling upward to the right, the graph will change substantially in the same way plus side both from the flat state (t ₃ ~t ₄ ).

Further, when the rolling changes from the upward rising state to the upward rising state, the graph temporarily changes to the minus side (t ₅ ), and when the movement of the right end of the substrate 53 is reversed, the slope sensor 18a. It can be seen that the oil surface of Nos. 18b fluctuates due to shaking back.

At this time, looking at the graph, it can be seen that the difference between the graph and the swing-back portion (t ₅ ) is large, and the graph projects further to the minus side. That is, in FIG. 6B, the slope sensor 18b far from the lower left end 55 is greatly disturbed. Therefore, in the swing-back control described later, the rolling control is performed with reference to the slope sensor value S _S (the one shown in the graph at t ₅ in FIG. 7) having the smaller swing-back (closer to the neutral value).

This swing-back also subsides in a short time, and as the tractor 10 rolls to the left, the graphs change from the flat state to the minus side in the same manner (t _{5 to} t). ₆ ). Hereinafter, similarly, each time the rolling direction changes to the left or right, the graph temporarily changes to the opposite side (t ₇ , t ₈ ), and it can be seen that the oil level of the slope sensors 18a, 18b fluctuates due to rocking back. .

FIG. 8 shows two slope sensors 18a, 18
The difference between the signals detected by b is obtained and the absolute value of the difference (hereinafter referred to as “difference d”) is expressed. When the rolling on the tractor 10 is large and the impact is strong, the difference d between the two slope sensor values Becomes large, and when rolling is small, the difference d between the two slope sensor values also becomes small,
To some extent it can be ignored. Therefore, the set value α is set in advance, and when the difference d between the two slope sensor values exceeds the set value α, it can be detected that the swing-back occurrence portion is present.

The control relating to this swing-back detection will be described with reference to FIGS. 9 to 12. FIG. 9 is a flowchart of the swing-back detection control. First, the slope sensor 1
The detection signals of 8a and 18b are read (step 20
0), the difference d between the two slope sensor values is obtained (step 210). At this time, it is determined whether or not the difference d is greater than or equal to the set value α shown in FIG. 8 (step 220). If the difference d is less than the set value α, there is no rocking back.
Alternatively, it is assumed that the swing-back is small and can be ignored, and the rolling control is continued or restarted (step 220 → 26).
0).

On the other hand, when the difference d is equal to or greater than the set value α, it is determined that the swinging is back (step 220 →
230), the rolling control is temporarily suspended until a certain time has elapsed (step 240 → 250). Then, after a lapse of a certain time, the original control is returned to.

FIG. 10 is a flowchart of the swing-back detection control. The points different from the swing-back detection control are shown in FIG. 7 when the swing-back is determined in step 330.
As explained at t ₃ and t ₅ in the graph of, the slope sensor value S of the one with less swingback (the one closer to the neutral value)
_{With S} as a reference, rolling control is performed until a certain time has elapsed (step 340 → 350).

On the other hand, the rate of change in the graph shown in FIG. 8 is calculated, and when the absolute value of the rate of change (hereinafter referred to as "rate of change Δd") suddenly increases within a certain period of time, the swing-back occurrence portion occurs. It can also be detected.

FIG. 11 is a flowchart of the swing-back detection control. First, the detection signals of the slope sensors 18a and 18b are read (step 400), and the difference d between the two slope sensor values is obtained (step 410). Further, the rate of change Δd of the difference d is calculated (step 420), and it is determined whether or not the rate of change Δd is greater than or equal to the set value β (step 430). At this time, when the rate of change Δd is less than the set value β, there is no swingback or the swingback is small and can be ignored, and the rolling control is continued or restarted (steps 430 → 470).

On the other hand, the change rate Δd is the set value β.
If it is above, it is determined that the shaking is performed (step 4).
30 → 440), and the rolling control is temporarily suspended until a certain time has elapsed (step 450 → 460). Then, after a lapse of a certain time, the original control is returned to.

FIG. 12 is a flowchart of the swing-back detection control. The difference from the swing-back detection control is that when the swing-back is determined in step 540, the one with less swing-back (the one closer to the neutral value). With reference to the slope sensor value S _S in (1), rolling control is performed until a certain time has elapsed (step 550 → 560).

In this way, the two slope sensors 18
By arranging a and 18b in parallel and detecting swinging back from changes in the respective slope sensor values, an error in the slope sensor value can be reduced and an accurate rolling angle can be calculated.

The present invention can be variously modified without departing from the spirit of the present invention, and it goes without saying that the present invention extends to the modified ones.

[0050]

As described above, according to the present invention, the pressure rod for restricting the movement of the rear cover is provided with the spring, and the expansion and contraction of the spring is restricted so that the movement amount of the rear cover can be automatically adjusted. is there. Therefore, when the rear cover jumps up during traveling work, the jumping up of the rear cover is automatically restricted while the operator is sitting in the driver's seat, and the malfunction of the depth control can be prevented.

[Brief description of drawings]

FIG. 1 is a side view of a tractor showing an embodiment of the present invention and connected with a rotary working machine.

FIG. 2 is a side view of a main part of a mounting portion of a pressure rod 30.

FIG. 3 is a block diagram of an attitude control system of a rotary working machine.

FIG. 4 is a flowchart of control for automatically adjusting the amount of movement of the rear cover.

FIG. 5A is a front view of a slope sensor provided with a plurality of detection units. (B) is a graph showing the difference in voltage between the two detectors.

FIG. 6 (a) is a front view showing a state where two slope sensors arranged in parallel rise to the left. (B) is a front view of a state in which two slope sensors arranged in parallel rise to the right.

FIG. 7 is a graph showing signals detected by two slope sensors during rolling.

FIG. 8 is a graph showing an absolute value of a difference between signals detected by two slope sensors.

FIG. 9 is a flowchart showing swing-back detection control.

FIG. 10 is a flowchart showing swing-back detection control.

FIG. 11 is a flowchart showing swing-back detection control.

FIG. 12 is a flowchart showing swing-back detection control.

[Explanation of symbols]

 10 Tractor 12 Rotary Working Machine 26 Main Cover 27 Rear Cover 28 Depth Sensor 29 Bracket 30 Pressure Rod 32 Spring 35 Slider 38 Bell Crank 39 Stepping Motor 40 Arm 41 Rod

Claims (1)

[Claims] 1. A rotary working machine connected to a rear part of a tractor, wherein a rear cover is rotatably attached to a rear end of a main cover and rotation of the rear cover is detected to control a working depth of the rotary working machine. In addition, a bracket is fixed to the main cover and the upper part of the pressure rod is attached,
In a rotary working machine in which the lower end of the pressure rod is connected to a rear cover and a spring is interposed in the pressure rod to restrict the movement of the rear cover, the expansion and contraction of the spring is regulated to automatically adjust the movement amount of the rear cover. A depth control device for a rotary working machine, which is formed to be adjustable.