JPH06212660A - Blade tilting angle control device for motor grader - Google Patents

Abstract

PURPOSE:To change an objective blade tilting angle by an operation lever. CONSTITUTION:There are provided a first operation lever 22 which is operable in any arbitrary direction and outputs a signal based on the operation direction and an operation stroke and a controller 26 which sets first and second proportional solenoid valves 30-1 and 30-2 to an expansion position by manipulating this first operation lever 22 in the front and the rear and sets a blade to an objective tilting angle by expanding right and left lift cylinders 3 and 4. When the first operation lever 22 is manipulated on both ways, the controller 26 tilts the blade on both ways without any relation about the objective blade tilting angle and sets the blade tilting angle as an object blade tilting angle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling a blade inclination angle of a motor grader.

[0002]

2. Description of the Related Art A motor grader is known in which a drawbar is provided on a vehicle body so that the drawbar can be swung up and down by a left and right lifting cylinder, a circle is swingably mounted on the drawbar by a swing hydraulic motor, and a blade is mounted on the circle. . In this motor grader, the stroke of the left and right lifting cylinders is made different so that the blade tilts left and right with respect to the horizontal, and the blade tilt angle changes the vehicle body tilt angle due to the unevenness of the work road surface and the left and right slope changes, and the circle turns. It changes by changing the angle of the blade with respect to the traveling direction, that is, the propulsion angle.

For this reason, there has been proposed a blade inclination angle control device for automatically controlling the blade inclination angle to a set angle even if the vehicle body inclination angle or the blade propulsion angle changes.

[0004]

The above-described blade inclination angle control device is provided with a target blade inclination angle setting means such as a dial or a switch, and by setting the target blade inclination angle by this setting means, a change in the vehicle body inclination angle or Even if there is a change in the blade propulsion angle, the blade inclination angle is always maintained at the target blade inclination angle, and the operator must operate the target blade inclination angle setting means to change the target blade inclination angle.

For this reason, when the work road surface is curved and the left and right slopes are continuously changed, or when it is necessary to continuously perform a desired blade inclination angle such as an intersection with another work road surface, the operator sets a target. It is very difficult to appropriately change and set the blade inclination angle.

Therefore, an object of the present invention is to provide a blade inclination angle control device for a motor grader which can solve the above-mentioned problems.

[0007]

An operation member for outputting different first and second signals, left and right elevating cylinders 3 and 4 for elevating and lowering a blade 9, and a blade inclination for detecting a horizontal inclination angle of the blade 9 with respect to the horizontal direction. The angle sensor 13, the first and second valves for supplying pressure oil to the left and right lifting cylinders 3, 4, and the first signal from the operating member are used to set the left and right inclination angle of the blade 9 to the target blade inclination angle. An expansion / contraction signal is output to the first and second valves, and an expansion / contraction signal is output to the first and second valves to incline the blade 9 to the left and right in response to the second signal from the operating member. A motor grade blade tilt angle control device comprising a controller 26 for resetting the angle to a target blade tilt angle.

[0008]

[Operation] By outputting a second signal from the operating member, the blade 9 can be tilted to the left or right regardless of the set target blade tilt angle, and the blade tilt angle at that time can be reset as the target blade tilt angle. The target blade inclination angle can be changed by operating the operation member, and the operation is simplified, so that the target blade inclination angle can be continuously and easily changed during the work of continuously leveling the work road surface.

[0009]

[Example] As shown in Fig. 1, the motor grader
A drawbar 2 is swingably supported on the front end of the vehicle body 1, and the left and right lifting cylinders 3, 4 extend between the drawbar 2 and the vehicle body 1.
Also, a horizontal feed cylinder 5 is connected, a swing circle 6 is swingably provided on the drawbar 2 by a swing hydraulic motor 7, and a blade 9 is provided on a bracket 8 of the swing circle 6 by a shift cylinder 10 so as to be movable left and right. , Front wheel 1
1 can be tilted to the left and right (leaning) by a leaning cylinder (not shown). As a motor grader, there are known a motor grader provided with a scarifier at a front end portion of a vehicle body so as to be vertically movable by a cylinder for the scarifier, and a vehicle body capable of being bent by a steering cylinder.
The turning hydraulic motor 7 is provided with a potentiometer 12 for detecting its rotation.
The blade swivel angle is detected by the output signal of 2. The swivel circle 6 has a blade slant angle sensor 13 for detecting the horizontal slant angle of the blade 9 with respect to the horizontal.
Is provided.

As shown in FIG. 2, the seat 21 of the cab 20
A first operating member, for example, a first operating lever 22 and a second operating member, for example, an operating lever 23 are provided on the left and right sides of the vehicle, and a handle 24 is provided in front of the seat 21. The first
The second operation levers 22 and 23 may be attached to the left and right sides of the support member 25 of the handle 24. The first and second operation levers 22 and 23 can be tilted in the front-rear direction, the right and left rightward directions, and the oblique front-rear and left-right directions, and output an electric signal proportional to the operation stroke. That is, when the left and right operation levers 22 and 23 are operated, the potentiometer is rotated to output an electric signal corresponding to the operation direction and proportional to the operation stroke.

The output signals of the first and second operation levers 22 and 23 are input to a controller 26 as shown in FIG. 3, and ON / OFF signals are input to the controller 26 from a changeover switch 27, and tilting is performed. Sensor 28
The vehicle body tilt angle signal is input from the potentiometer 1
A turning circle rotation angle signal is input from 2, and the controller 26 outputs an electric signal to a directional control valve that supplies pressure oil to each cylinder and a turning hydraulic motor, for example, a solenoid of a proportional solenoid valve 30 based on the input signal. At the same time, a signal is sent to the display panel 31 to display the operation status and the like.

As shown in FIG. 2, the display panel 31 is attached to the right side of the seat 21 in the cab 20, and the display panel 31 displays the operating condition and the target blade inclination angle as shown in FIG. And automatic ON / OFF button 41
And a target blade inclination angle setting button 42 and the like.

FIG. 5 is a hydraulic circuit diagram. The proportional solenoid valve 30 is a first proportional solenoid valve 30-1 for supplying pressure oil to the left lifting cylinder 3 and a second proportional solenoid for supplying pressure oil to the right lifting cylinder 4. The solenoid valve 30-2, the third proportional solenoid valve 30-3 that supplies pressure oil to the lateral feed cylinder 5, the fourth proportional solenoid valve 30-4 that supplies pressure oil to the shift cylinder 10, and the steering cylinder 32 are supplied with pressure oil. A fifth proportional solenoid valve 30-5 for supplying and a sixth proportional solenoid valve 3 for supplying pressure oil to the leaning cylinder 33.
0-6, a seventh proportional solenoid valve 30-7 for supplying pressure oil to the scarifier cylinder 34, and an eighth proportional solenoid valve 30-8 for supplying pressure oil to the swing hydraulic motor 7 are provided. The controller 26 sends an energization signal to the proportional solenoid valves 30-1 to 30-8 to switch the proportional solenoid valves 30-1 to 30-8, thereby supplying the pressure oil discharged from the hydraulic pump 35 to each cylinder and the swing hydraulic motor 7. In addition,
The first to eighth proportional solenoid valves 30-1 to 30-8 are switched by a stroke proportional to the energization amount so that the opening area (supply flow rate) is proportional to the energization amount.

The first operating lever 22 is operated as shown in FIG. 6 to the front, rear, left, right, right front, right rear, left front and left rear, and an electric signal proportional to the operation stroke is shown in FIG. Output to. The electric signal output from the first operation lever 22 is sent to the controller 26 and the changeover switch 2
The operation pattern is determined by the ON and OFF signals of 7 and the combination of the output signals is selected.

The second operating lever 23 is operated forward, rearward, leftward and rightward as shown in FIG. 8, and outputs an electric signal proportional to the operating stroke as shown in FIG. This second
The electric signal output from the operating lever 23 is the controller 26.
The operation pattern is judged by the ON / OFF signal of the changeover switch 27 and the combination of the output signals is selected.

Next, the operation of automatically controlling the blade inclination angle to the target inclination angle will be described. Display panel 31 shown in FIG.
By turning on the automatic ON / OFF button 41, the blade tilt angle control mode is set, and the target blade tilt angle setting button 42
The target blade inclination angle set by operating is displayed on the display unit 40 and input to the controller 26. When the first operation lever 22 is operated forward, the controller 26 outputs expansion signals of different magnitudes to the first and second proportional solenoid valves 30-1 and 30-2 in accordance with the target blade tilt angle to output the expansion position a. Move different strokes toward
The second proportional solenoid valves 30-1 and 30-2 have different opening degrees according to the target blade inclination angle, and the pressure oils having different flow rates are supplied to the extension chambers 3a and 4a of the left and right lifting cylinders 3 and 4, respectively. The blades 9 and 3 are extended at different speeds and the blade 9 is tilted left and right with respect to the horizontal to obtain the target blade tilt angle.
The actual inclination angle of the blade 9 is determined by the blade inclination angle sensor 1
It may be detected in step 3 and fed back to the controller 26 so that the actual inclination angle matches the target blade inclination angle.

At this time, the blade propulsion angle is calculated from the detection value of the potentiometer 12, and the target blade inclination angle is corrected by the blade propulsion angle to correct the horizontal inclination angle of the blade 9 with respect to the horizontal even if the blade propulsion angle is different. The target blade tilt angle should be achieved. That is, even if the inclination angle of the blade 9 is constant, if the blade 9 is turned to the left or right from a posture orthogonal to the traveling direction and the blade propulsion angle is changed, the horizontal inclination angle of the blade 9 with respect to the horizontal is different,
Since the target blade tilt angle is the tilt angle when the blade 9 is in the posture perpendicular to the push button direction, even if the target blade tilt angle is corrected and the blade 9 turns, the horizontal tilt angle of the blade 9 with respect to the horizontal is always the same. To do so.

As described above, when the blade inclination angle is automatically controlled to reach the target blade inclination angle,
The operation of changing the target blade inclination angle will be described. When the first operation lever 22 is operated to the right front, the controller 26
By outputting different expansion signals to the first and second proportional solenoid valves 30-1 and 30-2, the left and right lifting cylinders 3 and 4 are expanded at different speeds, and the blade 9 is lowered to the right, so that the actual blade inclination angle is the target. Unlike the blade inclination angle, the actual blade inclination angle when the first operation lever 22 is set to the neutral position is detected by the blade inclination angle sensor 13 and is input to the controller 26 and the display panel 31, and the value is set as the target blade inclination angle. Is displayed on the display unit at the same time. The same applies to the case where the first operation lever 22 is operated to the right rear, left front, and left rear to change the blade inclination angle to the upper right, the lower left, or the upper left.

When the automatic ON / OFF button 41 is turned off, the above-mentioned operation for matching the blade inclination angle with the target inclination angle and the operation for changing the target blade inclination angle are eliminated.
It will be normal operation. In this embodiment, since the normal operation and the automatic tilt angle control operation are performed by the same operation member, the automatic ON / OFF button is provided, but an operation member dedicated to the automatic tilt angle control operation may be provided.

Next, another embodiment of the operating member will be described. FIG. 10 shows the second embodiment, and the first operating member 50 and the second operating member 60 are of the push button type having a plurality of push button switches. That is, the first operating member 50 is the rectangular main body 5
1, the left front push button switch 52 is located near the left front corner corner 51a, the right front push button switch 53 is located near the right front corner angle 51b, the left rear push button switch 54 is near the left rear corner corner 51c, and the right rear corner corner 51.
The right rear push button switch 55 is provided near the d side, and the front push button switch 5 is provided near the left and right middle front portions 51e of the main body 51.
6. A rear push button switch 57 is provided near the left-right intermediate rear portion 51f, a left push button switch 58 is provided near the front-rear intermediate left portion 51g, and a right push button switch 59 is provided near the front-rear intermediate right portion 51h.

When each push button switch is pushed, an electric signal is output, and the level of the output electric signal gradually increases in proportion to the duration of the pushing operation.
0 has the same function as the first operation lever 22 described above.
The push button switches may have ON and OFF functions.

Since each of the push button switches has a triangular shape and is arranged between the corner portions and the push button switches adjacent to each other, the push button switches can be efficiently arranged in the small main body 51, which is compact. The function of the push button switch, that is, the type of the actuator to be operated can be easily determined by the position of each push button switch, and the operability of the operator can be improved.

The second operating member 60 is a rectangular main body 61.
A front push button switch 62 near the left and right middle part front part 61a, a rear push button switch 63 near the left and right middle part rear part 61b, a left push button switch 64 near the front and rear middle left part 61c, and a right push button switch 65 near the front and rear middle right part 61d. Each is provided.

When each push button switch is pressed, an electric signal is output, and the level of the output electricity gradually increases in proportion to the length of time the button is kept pressed. This right operating member 60 is similar to the second operating lever 23 described above. It has various functions. Each push button switch may have an ON / OFF function.

FIG. 11 shows a third embodiment, in which the main body 51 of the first operating member 50 has a shape curved in the left-right direction in a long shape,
This main body 51 has a left push button switch 58 and a right push button switch 5
9, a rear push button switch 57, a front push button switch 56, a left rear push button switch 54, a left front push button switch 52, a right rear push button switch 55, and a right front push button switch 53 are sequentially arranged from the left.

The main body 61 of the second operating member 60 has a shape that is curved in the left-right direction in a long direction, and a front push button switch 62, a rear push button switch 63, a right push button switch 65, and a left push button switch 64 are sequentially arranged from the left on this main body 61. They are arranged side by side.

In this way, the first operating member 50 and the second operating member 51 can be arranged close to the left and right of the seat 21, so that the distance from the operator to each push button switch is shortened and it is easy to operate. .

FIG. 12 shows a fourth embodiment, in which a main body 51 of the first operating member 50 is formed in a rectangular shape elongated in the left-right direction, and a rear push button switch 57, a left push button switch 58, a right push button switch 59, a left side are provided on the main body 51. A rear push button switch 54 and a right rear push button switch 55 are sequentially arranged from left to right, a front push button switch 56 is provided near the front part between the rear push button switch 57 and the left push button switch 58, and a right push button switch 59 and a left rear push button. A left front push-button switch 52 is provided near the front of the switch 54, and a right front push-button switch 53 is provided near the right front of the right rear push-button switch 55. In this way, the player feels like playing a piano with his left hand. The push button switch can be operated.

As shown in FIG. 12, the main body 61 of the second operating member 60 has a rectangular shape that is long in the left-right direction.
A rear push button switch 63, a left push button switch 64, and a right push button switch 65 are sequentially arranged from the left side on the rear push button switch 6
A front push button switch 62 is provided near the front portion between the left push button switch 3 and the left push button switch 64. In this way, the push button switch can be operated by playing the piano with the right hand. To automatically control the blade tilt angle with these operating members,
The front push button switch 56 and the rear push button switch 57 of the first operation member 50 are pushed to input the front signal and the rear signal to the controller 26 to operate in the same manner as described above. The left front, left rear, right front and left rear push button switches 52, 54 , 53, 55 to input a front left signal, a rear right signal, a front right signal, and a rear right signal to the controller 26 and operate in the same manner as described above.

FIG. 13 shows a fifth embodiment, in which the main body 51 of the first operating member 50 has a rectangular shape elongated in the left-right direction, and the main body 51 is provided with first, second, third and fourth push buttons 70, 71, 7
2, 73 are arranged side by side from the left, and the first, second, third, and fourth switches 70, 71, 72, 73 are swingable about the front and rear intermediate points, and the front portion 7 of the first switch 70 is movable.
When 0a is pressed, a front left signal is output, and when the rear portion 70b is pressed, a rear left signal is output. Similarly, the front portion 71a of the second switch 71 is output.
When pressing, the front signal is output, when the rear signal 71b is pressed, the rear signal is output, when the front portion 72a of the third switch 72 is pressed, the left signal is output, when the rear portion 72b is pressed, the right signal is output, and the front portion of the fourth switch 73 is output. When the 73a is pressed, the right front signal is output, and when the rear part 73b is pressed, the right rear signal is output, and the first, second, third and fourth switches 70,
Reference numerals 71, 72 and 73 are seesaw switches.

The first and second main bodies 61 of the second operating member 60 are
The switches 74 and 75 are provided, and the first and second switches 7
4 and 75 can swing freely around the middle of the front and rear,
When the front portion 74a of the switch 74 is pressed, a front signal is output, and when the rear portion 74b is pressed, the seesaw switch outputs a rear signal. When the front portion 75a of the second switch 75 is pressed, a left signal is output.
It is a seesaw switch that outputs a right signal when the rear part 75b is pressed. In order to automatically control the blade inclination angle with this operating member, the second switch 71 of the first operating member 50 is used.
The front part 71a and the rear part 71b are pushed to input the front signal and the rear signal to the controller 26 to operate in the same manner as described above.
The front and rear portions of the fourth switches 70 and 73 are pressed to output a front left signal, a rear left signal, a front right signal, and a rear right signal to the controller 26.
Input to and operate in the same manner as described above.

Next, another embodiment of the directional control valve will be described.
Although the directional control valve is a proportional solenoid valve in the above embodiment, as shown in FIG. 14, the pilot type switching valve 80 that is switched by pilot pressure and the pilot pressure receiving portion 81 of the pilot type switching valve 80 have pilot pressures. To the solenoid 26 of the proportional solenoid valve pressure control valve 82.
Alternatively, the opening of the pilot switching valve 80 may be set to a value proportional to the amount of energization by further energizing.

[0033]

The blade 9 receives the first signal from the operating member.
The right and left inclination angle of the blade can be matched with the target blade inclination angle, and the blade 9 can be inclined to the left and right regardless of the target blade inclination angle set by the second signal from the operation member. It can be reset as a corner. Therefore, the blade 9 can be matched with the target blade inclination angle by operating the operation member, and the target blade inclination angle can be changed, so that the operation is simplified and the target is achieved during the work for continuously leveling the work road surface. The blade inclination angle can be easily changed continuously.

[Brief description of drawings]

FIG. 1 is a side view of a motor grader.

FIG. 2 is a perspective view of a driver's cab provided with the operating device of the present invention.

FIG. 3 is a perspective view of an operating device.

FIG. 4 is a front view of a display panel.

FIG. 5 is a hydraulic circuit diagram.

FIG. 6 is an explanatory diagram of an operation direction of a left operation lever.

FIG. 7 is a chart showing a relationship between a stroke and an output signal.

FIG. 8 is an explanatory diagram of an operation direction of a right operation lever.

FIG. 9 is a chart showing a relationship between a stroke and an output signal.

FIG. 10 is an explanatory diagram of a second embodiment of the operating member.

FIG. 11 is an explanatory view of a third embodiment of the operating member.

FIG. 12 is an illustration of a fourth embodiment of the operating member.

FIG. 13 is an explanatory diagram of a fifth embodiment of the operating member.

FIG. 14 is an explanatory diagram of another example of the directional control valve.

[Explanation of symbols]

2 ... Drawbar, 3 ... Left lift cylinder, 4 ... Right lift cylinder, 5 ... Traverse cylinder, 6 ... Swing circle, 7 ... Swing hydraulic motor, 9 ... Blade, 10 ... Shift cylinder, 1
2 ... Potentiometer, 13 ... Blade inclination angle sensor, 22 ... First operating lever, 23 ... Right operating lever, 26
... controller, 31-1 ... first proportional solenoid valve, 30-2
… Second proportional solenoid valve.

Claims (6)

[Claims] 1. An operating member for outputting different first and second signals, and left and right lifting cylinders 3, 4 for lifting and lowering a blade 9.
A blade inclination angle sensor 13 for detecting a horizontal inclination angle of the blade 9 with respect to the horizontal, first and second valves for supplying pressure oil to the left and right lifting cylinders 3, 4, and a first signal from the operating member. To output the expansion / contraction signal to the first and second valves for which the left / right tilt angle of the blade 9 should be the target blade tilt angle, and to tilt the blade 9 left / right by the second signal from the operating member. A blade inclination angle control device for a motor grader configured by a controller 26 that outputs an expansion / contraction signal to the second valve and resets the blade inclination angle at that time to the target blade inclination angle. 2. The controller 26 has a first function of performing a normal blade elevation by a first signal from the operation member and a normal blade inclination by a second signal, and a first function by the operation member. A second function of resetting the target blade tilt angle by a signal to match the aforementioned blade tilt angle with the target blade tilt angle, and a second signal based on the blade tilt and the blade actual tilt angle from the blade tilt angle sensor 13. The blade inclination angle control device for a motor grader according to claim 1, further comprising means for switching the controller 26 between the first function and the second function. 3. The operation member can be operated in any direction,
The blade inclination angle control device for a motor grader according to claim 1 or 2, wherein the operation lever outputs a signal proportional to an operation direction and an operation stroke. 4. The switch according to claim 1, wherein the operation member is a switch.
Alternatively, the blade inclination angle control device of the motor grader according to the above item 2. 5. The blade tilt angle control device for a motor grader according to claim 1, wherein the valve is a proportional solenoid valve. 6. The blade inclination angle control device for a motor grader according to claim 1, wherein the valve is a pilot type switching valve and a proportional electromagnetic pressure control valve.