JPS5820835A - Controller for angle of bucket of arm type working machine - Google Patents

Abstract

PURPOSE:To hold the angle of a bucket with a high accuracy as well as prevent the hunting of the bucket by hastening the response of control by using a system in which the angular velocity of the bucket is controlled by the angular veloxity signal of the operating arm and its position is controlled by the deviation signal of the angular veloxity. CONSTITUTION:When operating an operating arm, the angular velocity signals alpha, beta, and gamma of the operating arm are obtained by angle guages 8, 9, and 10, angular velocity signal gamma' according to the angular velocity of the bucket is obtained from the angular velocity signals alpha, beta and gamma, and the bucket is turned by open- loop control at the angular velocity corresponding to gamma. On the other hand, an angle deviation signals DELTAgamma is obtained and control is also made on position feedback. The sum of the angular velocity control signal gamma' and the angle deviation signal DELTAgamma is output, the highest one of the oil pressure of the output and the pilot pressure of the pilot operation valve 13 is supplied to the switching valve 12 of the oil-pressure cylinder 7 of the working machine, and the valve 12 is controlled by shuttle valves 23a and 23b.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for controlling the backt angle of an armhole working machine such as a loading hydraulic excavator or a backhoe hydraulic excavator.

To prevent earth and sand from falling when lifting the boom of a loading hydraulic excavator, or to keep the excavation angle constant when excavating on slopes or horizontal surfaces with a backhoe hydraulic excavator.
Even during the operation of the working arm, ie, the boom or arm, it is necessary to keep the angle of the blade from the horizontal plane, ie, the absolute angle, constant, and such operations require advanced technology and a great deal of effort. In order to solve this problem, the absolute angle of the packet should be automatically kept constant without the need for back-up operation.There are several ways to do this: a link method, a hydraulic method, and an electrical method. Several methods have been proposed.

FIG. 1 is a diagram showing the front part of a loading hydraulic excavator. In the figure, 1 is the hydraulic shield. A bell body, 2 a boom pivotally attached to the body 1, 3 an arm pivotally attached to the tip of the poom 2, 4 a packet pivotally attached to the tip of the arm 3, and 5 a spring that moves the poom 2 up and down. 6 is an arm cylinder that swings the arm 6; 7 is a packet cylinder that rotates the packet 4; 8 is an angle that detects the angle of the boom 2 with respect to the main body 11C, that is, the boom angle, and outputs the boom angle signal α. 9 is an angle meter that detects the angle of the arm 6 with respect to the boom 2, that is, the arm angle, and outputs an arm angle signal β; 10 is a bucket 40 with respect to the arm 6;
This is an angle meter that detects an angle, that is, a packet angle, and outputs a packet angle signal γ.

FIG. 2 is a diagram showing a conventional packet angle control device. In the figure, 11 is a hydraulic pump, 12 is a pilot operated flow control valve provided between the hydraulic pump 11 and the packet cylinder 7, 16 is a packet operating lever, and 14 is a pilot corresponding to one operation amount of the packet operating lever 13. 15 is a pilot operated valve that generates pressure, angle signals α and β.
, an adder for calculating the total value of γ, that is, the absolute angle signal θ;
16 is the output signal θ of the adder 15 when the switch 17 is turned on, that is, the target absolute angle signal θ. 18 is an output signal θ of the storage device 16.

19 is an adder/subtractor that calculates the difference between the output signal θ of the adder 15, that is, an angular deviation signal Δγ; 19 is a coefficient unit that multiplies the output signal Δγ of the adder/subtractor 18 by a coefficient and outputs Δγ as a signal; 20
is the output signal of the coefficient multiplier 19 when the switch 21 is on.
Amplifiers for amplifying and compensating for γ, 22a, 22b
23a is an electro-hydraulic conversion valve that generates a pilot pressure according to the output signal of the amplifier 20;

23b ii This is a shuttle valve that selects the higher of the pilot pressure of the pilot operation valve 14 and the pilot pressure of the electro-hydraulic conversion valves 22a and 22b and supplies it to the pilot port of the flow control valve 12. In addition, switch 17.2
1 is a boom operation lever, arm operation lever (not shown)
is turned on when at least one of the packet control levers 13 and 13 is in the operating position and the packet operating lever 13 is not in the operating position.

In this control device, when only the packet operating lever 15 is in the operating position, the pilot operating valve 14 generates a pilot pressure corresponding to the amount of operation of the packet operating lever 16, and since the switch 21 is off, the electric power is Since the pilot pressure of the hydraulic conversion valves 22a and 22b is zero, the pilot pressure of the pilot operation valve 14 is supplied to the flow rate control valve 12 via the shuttle valves 25a and 23b, so that the flow rate control valve 12 is connected to the packet operation lever 13. is switched by an amount corresponding to the amount of operation of the packet operation lever 13, and the packet 4 rotates at an angular velocity corresponding to the amount of operation of the packet operation lever 13. Further, when at least one of the boom operating lever and the arm operating lever is set to the operating position, the switch 17.21 is turned on, and the target absolute angle signal θ at that time. is stored in the storage device 16, and the angular deviation signal Δγ is obtained from the adder/subtractor 1st.
is output, Δγ is output as a signal from the coefficient unit 19, and a pilot pressure corresponding to Δγ is generated as a signal from the electro-hydraulic conversion valves 22a and 22b.On the other hand, since the pilot pressure of the pilot operating valve 14 is zero, the electric hydraulic conversion valve 22a,
The pilot pressure of 22b is applied to the shuttle valves 23a, 2
Since the packet 4 is supplied to the flow rate control valve 12 via the signal 3b, the packet 4 rotates at an angular velocity according to the signal Δγ. By the way, the boom angle, arm angle, and packet angle are each A.
1, B, and F, the absolute angle θ of the back blade 4 is expressed by the following equation.

θ=A0B+r10 Here, C is a constant value determined by the shape of the bag nose 4, etc. Therefore, since the absolute angle signal θ=α+β0r has a value according to the absolute angle θ, K for keeping the absolute angle θ constant may be set so that the absolute angle signal θ becomes constant. In this device, the target absolute angle signal θ.

The bucket 4 is rotated at an angular velocity according to the difference between the angle signal θ and the absolute angle signal θ, that is, the angular deviation signal Δγ. Therefore, even if the angle signals α, β, and r change, the absolute angle θ of the bucket 4 is maintained at the value at the time when the operation of the boom operating lever and the arm operating lever was started.

In this state, when the packet controller 13 is also set to the operating position, switches 17 and 21 are turned off.

The bucket 4 rotates at an angular velocity according to the amount of operation of the bucket operation lever 13.

In this way, when automatically controlling the bucket 4, the bucket 4 is rotated at an angular velocity according to the angular deviation signal Δγ. Therefore, in order to rotate the bucket 4 at a certain angular velocity, the angular deviation signal Δγ must always be non-zero. is necessary. By the way, normally, if you increase the gain k of the control system, you can always keep the -angular deviation signal Δγ small, but in a system with a large delay such as a hydraulic excavator, increasing the gain k will cause hunting. , the gain k must be made small, and in this case, the angular deviation signal Δγ becomes considerably large, making it impossible to accurately control the back-nod angle. In addition, when manual operation of the packet 4 is started while the bucket 4 is automatically controlled, the packet 4 is moved from the bucket operation lever 1 at that point 75).
It rotates at an angular velocity according to the amount of operation in step 3. For this reason, when the packet 4, which was rotating at a predetermined angular velocity during automatic control, operates the bat operation lever 16, it starts rotating at an angular velocity that is unrelated to the previous angular velocity, resulting in a smooth operation feeling. is not obtained. for example.

In order to keep the absolute angle θ of the bucket 4 constant during automatic control, the operator corrects the absolute angle θ of the bucket 4 to a smaller value while the packet 4 is rotating clockwise in FIG. When I operated the packet control lever 13 so that the packet 4 would rotate clockwise,
Bakunodo 4 commanded by Bakunodo operating lever 13
If the angular velocity is smaller than the angular velocity tag, the absolute angle θ of the bucket 4 will not become smaller but will instead become larger, which is contrary to the operator's intention and is dangerous.

This invention was made to solve the above-mentioned problems, and it is possible to precisely control the packet angle.

Another object of the present invention is to provide a bucket angle control device for an armhole working machine that can smoothly correct the absolute angle of the bucket during automatic control.

To achieve this object, the present invention includes at least one working arm pivoted by an oil field cylinder, a packet pivoted at the tip of the working arm and pivoted by a socket cylinder, and a packet cylinder rotatable by a socket cylinder. In a bucket angle control device for an armhole working machine, the speed control device is equipped with a packet operating lever and a pyro-operated cooking valve that supplies pilot pressure according to the operating tool of the speed control device. , an arithmetic unit for determining an angular velocity control signal corresponding to the angular velocity at which the bakunod should move from an angular velocity signal corresponding to the angular velocity of the working arm, and outputting the angular velocity control signal when operating the working arm; and a shuttle valve that selects the higher of the pilot pressure of the pilot operated valve and the pilot pressure of the electrohydraulic conversion valve and supplies it to the speed control device. . Further, an angular velocity control signal corresponding to the angular velocity at which the packet should move is determined from an angular velocity signal corresponding to the angular velocity of the working arm, and a difference between the target angle and the actual angle of the packet is determined from the angular velocity signal corresponding to the angle of the working arm. An arithmetic unit that calculates an angular deviation signal corresponding to the angular deviation signal and outputs a signal obtained by adding the angular velocity control signal and the angular deviation signal when the working arm is operated, and generates a pilot pressure in accordance with the output signal of the arithmetic unit. an electro-hydraulic conversion valve,
A shuttle valve is provided that supplies the higher of the pilot pressure of the pilot operation valve and the pilot pressure of the electrohydraulic conversion valve to the speed control device.

FIG. 3 is a diagram showing a packet angle control device according to the present invention. In the figure, 24 is an adder for calculating the sum of the boom angle signal α and the arm angle signal β.

25 is a differentiator that differentiates the output signal α+β of the adder 24;
26 is an adder that calculates the difference between Δγ in the output signal of the coefficient multiplier 19 and the output signal λmean of the differentiator 25; 27 is a switch provided between the adder 26 and the amplifier 20; 28
．． 29 is the boom operation lever and arm operation respectively / (
-, 30 to 32 are operating levers 28, 29, 13 respectively
36 is a control command device that controls the switch 17゜21.27, and the control command device 63 detects when at least one of the operation levers 2"'8.29 is in the operating position. Output control signal A.

When at least one of the operating levers 28 and 29 is in the operating position and the operating lever 13 is not in the operating position, the control signal B is output, and when the control signal A is output, the switch 2
7 is turned on and the control signal B is output, the switch 17.21 is turned on.

In this control device, when only the packet operation lever 16 is being operated, the control signals A and B are not output from the control command device 63, so the switches 17, 21',
27 is off, the electro-hydraulic conversion valves 22a, 2
2b is zero, and the pilot pressure of the pilot operating valve 14 is supplied to the flow rate control valve 12 via the shuttle and valves 26a1 and 23b, so the packet 4 moves at an angular velocity according to the amount of operation of the packet operating lever 16. Rotate.

In addition, if at least one of the operating levers 28 and 29 is operated and the operating lever 13 is not operated, the control command device 36
Since control signals A and B are output from switch 17.
21.27 is turned on, electro-hydraulic conversion valve 2,! a,
, 22b to the output signal of the adder 26, and Δγ
On the other hand, the pilot pressure of the pyrotechnical control valve 14 is zero, so the pilot pressure of the electro-hydraulic conversion valves 22a and 22b is the same as that of the shuttle valve 2.
Flow control valve 111C is supplied via 3a and 23b,
Therefore, the packet 4 rotates at an angular velocity according to the signal 'r + and Δγ. By the way, as mentioned above, the absolute angle signal θ corresponding to the absolute angle θ of packet 4 is expressed by the following formula % Formula % And when the absolute angle θ is constant, that is, when the absolute angle signal θ is constant, this formula is When differentiated, it becomes as follows.

Therefore, if the packet 4 is rotated at an angular velocity according to the angular velocity control signal Nmiru, the absolute angle θ of the packet 4 will be constant. When the absolute angle θ at the start of operation of the operating lever 28°29 fluctuates, the angular velocity' of the packet 4 is corrected according to Δγ to a signal proportional to the amount of fluctuation, and the absolute angle θ of the packet 4 is kept constant. In this state, when the packet operation lever 16 is also operated, only the control signal A is output from the control command device 66, so the switch 17.21 is turned off.Therefore, the adder 26 outputs the angular velocity control signal , and one of the electro-hydraulic conversion valves 22a, 22b outputs an angular velocity control signal.

Generates pilot pressure according to the For example, when the pump is raised, the angular velocity control signal becomes a signal to dump the packet 4, that is, a signal to contract the vacuum cylinder 7, so the electro-hydraulic conversion valve 22b generates pilot pressure. . In this case, the bucket operating lever 13
When is operated to the packet dump side, the shuttle valve 23b supplies the higher of the pilot pressure of the electro-hydraulic conversion valve 22b and the pilot pressure of the pilot operation valve 14 to the flow rate control valve 1. For this reason, when the bucket operation lever 13 is operated toward the bucket dump side, the pilot pressure of the electro-hydraulic conversion valve 22b is initially higher, so the packet 4 rotates at an angular velocity according to the angular velocity control signal. , Bakut operation "The operation lever 15 is further operated, and the pilot operation valve 14
When the pilot pressure becomes higher, the bucket 4 rotates at an angular velocity corresponding to the amount of operation of the packet operation lever 13.

On the other hand, when the packet operation lever 16 is operated to the bug-no-tilt side.

Since the pilot operation valve 14 generates pilot pressure on the shuttle valve 23a side, both i of the spool of the flow control valve 12
Since the pilot pressures of the electro-hydraulic conversion valve 22a and the Byronto operation valve 14 act on the two pilot pressures, the flow rate control valve 12 is switched by an amount corresponding to the differential pressure between the two pilot pressures.

Therefore, the back door 4 rotates at an angular velocity that is the difference between the angular velocity according to the signal and the angular velocity according to the operation amount of the packet operation lever 13. Therefore, the absolute angle θ of packet 4
can be corrected at a speed corresponding to the amount of operation of the packet operation lever 15. A similar operation is performed when the electro-hydraulic conversion valve 22a generates pilot pressure. In this state, move the packet operation lever 16 to the neutral position.
When the switch is returned to , the control signal B is output from the control command device 63 and the switches 17 and 2.1 are turned off. a. A. Storage device 1
．． "7" K is a short time point. A target absolute angle signal θ having a value corresponding to the absolute angle θ is stored, and the packet 4 holds that absolute angle θ from then on.

In addition, in the above-mentioned Example, although the packet angle control apparatus of the hydraulic excavator was demonstrated, it is not limited to a hydraulic excavator. In addition, in the above embodiment, the packet angle control device for the roasting and loading hydraulic excavator was explained.
The same is true for backhoe hydraulic excavators. Furthermore, one end of the packet cylinder 7 is pivotally connected to the poom 2 instead of the arm 3, and even if the arm 6 is swung, the absolute angle θ of the packet 4 is automatically kept almost constant. In the case of a structure such as a loader consisting of only the angular velocity signal and the packet 4, the angle and speed control signal n are obtained from the angular velocity signal of the poom 2, and the angular deviation signal Δγ is obtained from the boom angle signal α and the bucket angle signal γ. Good too. Also,
In the above embodiment.

Although the boom angle signal α, arm angle signal β, and packet angle signal γ are directly detected by angle meters 8 to 10, the angle signals α, β, and 5γ can be detected by detecting the amount of extension of cylinders 5 to 7, etc. It may also be obtained indirectly. Furthermore, in the above embodiment, by differentiating the angle signals α and β, the angular velocity signal a, ;! I asked for i, but
The angular velocity signal &, may be detected directly, or something corresponding to the angular velocity, such as the speed of the cylinders 5 to 7 or the flow rate of a pipe connected to the cylinders 5 to 7, may be detected. Also,
In the above-mentioned embodiment, the operation state of the operation lever 28.29 was detected by the lever operation detector 30.31. When automatically controlling arm 3 in a certain relationship, the control lever 2 is activated by the automatic control signal.
8.29 operation status may be detected, and Poom 2. Angular velocity signal of arm 6 &.

The operating state of the operating levers 28 and 29 may be detected by λ. Furthermore, the arithmetic unit may be constructed of an analog circuit or a digital circuit such as a microcomputer. Further, in the above embodiment, the flow rate control valve 12 is used as the speed control device, but a variable displacement pump may be used as the speed control device.

As explained above, in the backward angle control device for an arm-hole working machine according to the present invention, when operating nine working arms, the angular velocity is controlled based on the angular velocity signal of one working arm according to the angular velocity at which the packet should move. The packet is rotated at an angular velocity according to the angular velocity control signal 'rr, thereby performing open loop control. Therefore, compared to the conventional position feedback control method that controls the angular velocity of the angular deviation signal Δγ sepacket, the open loop control of the present invention has a faster response, does not cause hunting, and can reduce the weight of the load. If the influence of changes in system parameters and disturbances such as when a packet hits something is small, the packet angle can be controlled with high precision. and.

In addition to open-loop control, position feedback control using the angular deviation signal Δγ can be used even if the system parameters change and the influence of disturbances is large.

Since the resulting change in the absolute angle θ can be corrected by position feedback control, the packet angle can be controlled with great precision. In addition, when the packet control lever is operated while the packet angle is being automatically controlled, the angular velocity corresponding to the angular velocity control signal rr and the angular velocity corresponding to the operation amount of the Bakunodo control lever, whichever is greater, or both angular velocities With the angular velocity difference of packet 4
Since it is rotated, the absolute angle θ of the bag can be changed at a speed corresponding to the amount of operation of the packet control lever, so it is possible to smoothly correct the absolute angle θ of the packet during automatic control. . in this way,
The effects of this invention are remarkable.

[Brief explanation of the drawing]

ii Figure 2 is a diagram showing the front part of a hello-tef ink hydraulic excavator, Figure 2 is a diagram showing a conventional packet angle control device, and Figure 6 is a diagram showing a packet angle control device according to the present invention. 1 Oil field excavator body 2 ・Boom 6 ・Arm 4 ・Bakunod
5 Boom cylinder 6...Arm cylinder
719. Packet cylinders 8 to 10... Angle meter 12... Pilot operated flow rate control valve 13... Bakunodo operating lever 14... Pilot operated valve 15... Adder 16... Storage device 17.
...Switch 18...Adder/subtractor 19...Coefficient unit 20...Amplifier 21...Switches 22a, 22b...Electro-hydraulic conversion valve 25a,
23b ・Shuttle valve 24... Adder 25... Differentiator 26...
・Adder 27・・Switch 28・Boom operation lever 29・・Chi private operation lever 60-62・・Lever operation detector 53・・Control command device agent Junnosuke Nakamura

Claims (2)

[Claims] (1) at least one rotated by a hydraulic cylinder;
one working arm, and a packet pivoted at the tip of the working arm and rotated by a back cylinder. A packet angle control device for an armhole work machine, comprising a speed control device that controls the speed of the packet cylinder, and a pilot operation valve that supplies pilot pressure to the speed control device according to the operation amount of the packet operation lever, an arithmetic unit that calculates an angular velocity control signal corresponding to the angular velocity at which the packet should move from an angular velocity signal corresponding to the angular velocity of the working arm, and outputs the angular velocity control signal when operating the working arm;
An electrohydraulic conversion valve generates a pilot pressure in response to the angular velocity control signal, and the higher one of the pilot pressure of the pilot operation valve and the pilot pressure of the electrohydraulic conversion valve is selected and supplied to the speed control device. A packet angle control device for an arm hole working machine, characterized in that it is equipped with a shuttle valve that (2) At least one working arm that is rotated by a hydraulic cylinder, and a packet that is pivotally attached to the tip of the working arm and is rotated by a back cylinder. Packet angle control of an arm-hole work machine equipped with a speed control device that controls the speed of the above-mentioned cylinder, and a pilot operation valve that supplies pilot pressure to the speed control device according to the amount of operation of the packet operation lever. In the device, an angular velocity control signal corresponding to the angular velocity at which the packet should move is determined from an angular velocity signal corresponding to the angular velocity of the working arm, and an angular velocity control signal corresponding to the angle of the working arm is calculated between the target angle and the actual angle of the packet. An angular deviation signal corresponding to the difference is obtained, and when the working arm is operated, an arithmetic unit that outputs a signal obtained by adding the angular velocity control signal and the angular deviation signal, and a pilot pressure corresponding to the output signal of the multiplication calculator are provided. An armhole characterized by comprising an electro-hydraulic conversion valve that generates electricity, and a shuttle valve that supplies the higher of the pilot pressure of the pilot-operated valve and the pilot pressure of the electro-hydraulic conversion valve to the speed control device. Bucket angle control device for work equipment.