JPH079099B2 - Control device for power shovel - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a first boom pivotally supported by the swing body, a second boom pivotally supported by the first boom, and a second boom pivotally. The present invention relates to a control device for a power shovel that has a supported arm and a bucket that is pivotally supported by the arm.

[Prior Art] When excavating a corner portion of a groove using this type of power shovel, the first boom, the second boom and the arm are operated in combination to move the bucket upward in the vertical direction. There must be.

[Problems to be Solved by the Invention] However, operating the above-mentioned three types of working machines in a complex manner imposes a heavy burden on the operator, and requires a considerable degree of skill in the operation.

In view of such a situation, the present invention aims to reduce the labor of the operator.

[Means for Solving the Problems] The present invention includes a first boom pivotally supported by an upper swing body, a second boom pivotally supported by the first boom, and a second boom. A controller for a power shovel having an arm and a bucket pivotally supported by the arm, comprising: first angle detecting means for detecting an attitude angle of the first boom with respect to a horizontal plane; and the first boom with respect to the first boom. Second angle detecting means for detecting the attitude angle of the second boom, third angle detecting means for detecting the attitude angle of the arm with respect to the second boom, and the first, second and third angle detecting means. Calculating means for calculating the attitude angle of the arm with respect to the horizontal plane based on the angle detected by the means, and calculating a deviation between the arm attitude angle with respect to the horizontal plane and a preset target attitude angle; Disappear Thus, a cylinder control means for controlling the arm driving cylinder is provided.

[Operation] According to this configuration, the arm cylinder is operated so that the arm posture angle always becomes the target posture angle.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a control device according to the present invention, and FIG. 2 shows the configuration and working mode of a power shovel to which this control device is applied.

The power shovel shown in FIG. 2 has a first boom 1 whose base is pivotally supported by an upper swing body 5, a second boom 2 whose base is pivotally supported at the tip end of the first boom 1, and a power shovel shown in FIG. It has an arm 3 whose base is pivotally supported by the tip of the second boom 2 and a bucket 4 which is pivotally supported by the tip of the arm 3 so as to be rotatable about the longitudinal axis 1 shown.

Then, as shown in FIG. 3, a potentiometer 6 for detecting the attitude angle φ ₁ of the boom 1 with respect to a horizontal plane is provided at the rotation fulcrum of the first boom 1, and a rotation fulcrum of the second boom 2 is provided at the rotation fulcrum. A potentiometer 7 that detects the attitude angle φ ₂ of the boom 2 with respect to the first boom 1 is provided, and a potentiometer 8 that detects the attitude angle φ ₃ of the arm 3 with respect to the second boom 2 is provided at the rotation fulcrum of the arm 3. I am doing it.

The arm 3 is rotated by a hydraulic motor 34 for rotating the arm.

The first boom 1, the second boom 2, the arm 3 and the bucket 4 are swiveled by the first boom cylinder 11, the second boom cylinder 12, the arm cylinder 13 and the bucket cylinder 14 shown in FIG. 2, respectively.

FIG. 4 is a plan view showing the inside of the driver's seat provided on the upper swing body 5. In this driver's seat, two levers 15 and 16 that can be operated in the front and rear, left and right, and four pedals 17 to 20 are arranged, and the top of the grip portion 161 of the lever 16 is to specify the automatic mode. The push button switch 162 is attached. The push button switch 162 has a function of being set by the first action and being reset by the second action.

The longitudinal operating force of the lever 15 is transmitted to the switching valve 21 shown in FIG. The switching valve 21 has a function of applying its output pressure as a pilot pressure to the operation valve 22 for operating the upper swing body. Therefore, by operating the lever 15 in the front-rear direction, the upper swing is performed at a speed corresponding to the operation amount. The body driving hydraulic motor 23 is rotated forward and backward.

Also, the operating force in the left-right direction of the lever 15 is transmitted to the switching valve 24 shown in FIG. 1, whereby the output pressure of the switching valve 24 is piloted to the arm operating valve 26 via the shuttle valves 25A and 25B. Applied as pressure. Therefore, the lever 15
When is operated in the left-right direction, the arm cylinder 13 is expanded and contracted at a speed corresponding to the operation amount. That attitude angle φ ₃ of the arm 3 is changed.

The operating force of the lever 16 in the front-back direction is the switching valve shown in FIG.
Is transmitted to 27. As a result, the output pressure of the switching valve 27 becomes the first
Pilot pressure is applied to the boom operating valve 28. Therefore, by operating the lever 16 in the front-rear direction, the first boom cylinder 11 is expanded and contracted at a speed corresponding to the operation amount. That is the attitude angle φ ₁ of the first boom 1 is changed.

The operating force of the lever 16 in the left-right direction is transmitted to a switching valve (not shown), whereby the bucket operating valve (not shown) is piloted by the output pressure of the valve to operate the bucket.

On the other hand, the movement of the pedal 17 is transmitted to the potentiometer 29 shown in FIG. With this, the potentiometer 29 has a polarity corresponding to the stepping direction of the pedal,
A signal having a value corresponding to the stepping amount is output, and this signal is input to the controller 30.

Then, when the left end of the pedal 17 is depressed, a signal is supplied to the arm left rotation servo valve 31, and when the right end is depressed, a signal is supplied to the arm right rotation servo valve 32, respectively.
Along with this, pilot valves from the valves 31 and 32 are added to the arm rotation operation valve 33. Therefore, the stepping operation of the pedal 17 actuates the arm rotation motor 34, whereby the arm 3 is rotated about the axis l.

The movement of the pedal 20 is transmitted to the switching valve 35 shown in FIG. The output pressure of the valve 35 is the operation valve 36 for operating the second boom.
Since it acts as a pilot pressure on the second boom cylinder 12, when the pedal 20 is stepped forward and backward, the second boom cylinder 12 is expanded and contracted at a speed corresponding to the stepped amount.

The pedals 18 and 19 are operated when changing the traveling direction and traveling speed of the left traveling system and the right traveling system, respectively.

FIG. 5 shows the controller 3 based on the outputs of the pushbutton switches 162 attached to the potentiometers 6 to 8 and the lever 16.
The processing procedure of 0 is shown.

The operation of this embodiment will be described below with reference to FIG.

The controller 30 switches the switch 162 in step 200.
It is determined whether or not it is in the ON state, that is, whether or not the automatic mode is selected. Now, assuming that the push button switch 162 is pressed and the automatic mode is selected, the first boom 1, the second boom 1 and the second boom 2 are detected based on the outputs of the potentiometers 6, 7 and 8.
The attitude angles φ ₁ , φ _2, and φ _{3 of the} boom 2 and the arm 3 are input to the controller 30 (step 201), and then θ
= 2π−φ ₁ −φ ₂ −φ ₃ and Δθ = θ−θ
The calculation r is executed (step 202).

As is clear from FIG. 3, when the posture angle of the arm 3 with respect to the angle reference plane (horizontal plane) of the first boom 1 is θ, then φ
_{Since the} relation of ₁ + φ ₂ + φ ₃ + θ = 2π is established, the posture angle θ is represented as θ = 2π−φ ₁ −φ ₂ −φ ₃ . Therefore, in step 202, the current posture angle θ of the arm 3 and the deviation Δ between the posture angle θ and the target posture angle θr are calculated.
θ will be obtained.

When the angle deviation Δθ is obtained, it is determined in the next step 203 whether or not the angle deviation Δθ is zero. When it is determined that Δθ = 0, step 200
The contents of to 202 are executed again, and when it is judged that Δθ ≠ 0, the positive / negative judgment of the angular deviation Δθ is executed (step 204).

Then, if the decision result in the step 204 is YES, a control signal corresponding to the angular deviation Δθ is added to the servo valve 37 (step 205), and if the decision result is NO, a similar control signal is given. Added to servo valve 38 (step 20)
6).

The output pressure of the servo valve 37 acts as a pilot pressure for extending the arm cylinder on the operation valve 26 for arm operation via the shuttle valve 25A, and the output pressure of the servo valve 38 is the shuttle valve.
It acts on the operation valve 26 as a pilot pressure for retracting the arm cylinder via 25B. As a result, the posture angle θ of the arm 3
Is θ> θr, the arm cylinder 13 is extended and θ
Control is performed such that the cylinder 13 is retracted when <θr, whereby the posture angle θ of the arm 3 is held at the target posture angle θr.

Since this embodiment has such an action, when the bucket 4 is rotated 90 degrees to the side of the arm 3 to excavate the corner portion of the groove 39 as shown in FIG. 2, for example, the first boom 1 and the second boom 1 The posture angle θ of the arm 3 is always held at the target posture angle θr regardless of the turning angles φ ₁ and φ ₂ of ₂ . Therefore,
The bucket 4 is moved vertically from the bottom of the groove 39 by operating the first boom and the second boom so that the connection point of the arm 3 to the second boom 2 rises along a vertical line. become.

That is, according to this embodiment, it is possible to properly excavate the corner portion only by operating the first boom 1 and the second boom 2, and the operator's burden can be omitted because the operation of the arm 3 can be omitted. Can be reduced.

The target attitude angle θr can be arbitrarily set by the setter 40 shown in FIG. 1. When performing the corner digging as shown in FIG. 2, the target attitude angle θr is usually θr =
Set at 90 °.

Of course, the present invention is also applicable to the case of excavating with the blade edge of the bucket 4 facing the upper swing body 5 side as shown in FIG.

By the way, in order to switch the automatic mode to the manual mode, the push button switch 162 may be pressed again.However, if it is possible to manually interrupt the arm rotation during the operation in the automatic mode, the arm cylinder 13 can be urgently operated. This is convenient when activating the, or when temporarily correcting the arm posture angle.

The shuttle valve 41 and the pressure switch 42 shown in FIG. 1 are provided in consideration of this point. Now, when the switching valve 24 is manually switched from the neutral position while the automatic mode is selected, the output pressure of one or the other output port of the valve 24 is applied to the pressure switch 42 via the shuttle valve 41. Therefore, the pressure switch is turned on. That is, it is possible to detect that the switching valve 24 is manually operated from the output of the pressure switch 42.

Therefore, if the controller 30 is caused to perform the processing of cutting the control signals for the servo valves 37 and 38 based on the ON signal of the pressure switch 42, the automatic control of the arm cylinder 13 is interrupted and the manual operation is stopped. The cylinder can be controlled.

[Effects of the Invention] As is clear from the description of the above embodiment, according to the present invention, the arm cylinder is automatically controlled so that the posture angle of the arm becomes the target posture angle. Therefore, it is possible to excavate a corner portion or the like without operating the arm,
This can reduce the labor of the operator and facilitate the work.

Further, during excavation of the corner portion, since the attitude angle of the arm with respect to the horizontal plane is always kept constant, there is no danger of the arm coming into contact with surrounding objects,
Moreover, the posture of the bucket is prevented from changing during excavation of the corner portion, so that there is no possibility of causing inconvenience such as spilling of sand and sand from the bucket.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a power shovel control device according to the present invention, and FIG. 2 is a perspective view showing a configuration of a power shovel to which the present invention is applied and an excavation mode thereof.
FIG. 3 is a conceptual diagram showing the relationship between the posture angles of the first boom, the second boom, and the arm and the posture angle of the arm. FIG. 4 is a plan view conceptually showing the configuration of the driver's seat. The figure is a flow chart showing the processing procedure of the controller shown in FIG. 1 ... 1st boom, 2 ... 2nd boom, 3 ... arm,
4 ... Bucket, 5 ... Upper swing body, 6,7,8,29 ... Potentiometer, 11 ... First boom cylinder, 12 ... Second
Boom cylinder, 13 …… Arm cylinder, 15,16 …… Lever, 17-20 …… Pedal, 162 …… Push button switch, 21,2
2,27,35 …… Switching valve, 30 …… Controller, 31,32,37,38
...... Servo valve, 40 …… Shuttle valve, 42 …… Pressure switch.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP 54-96201 (JP, A) JP 56-150229 (JP, A) JP 59-68437 (JP, A) JP 60- 59237 (JP, A) Actual development Sho 59-160656 (JP, U)

Claims (1)

[Claims] 1. A first boom pivotally supported by an upper swing body, a second boom pivotally supported by the first boom, an arm pivotally supported by the second boom, and pivotally supported by the arm. A power shovel controller having a bucket and a first boom for detecting an attitude angle of the first boom with respect to a horizontal plane.
Angle detecting means, second angle detecting means for detecting an attitude angle of the second boom with respect to the first boom, and third angle detecting means for detecting an attitude angle of the arm with respect to the second boom. The attitude angle of the arm with respect to the horizontal plane is calculated based on the angles detected by the first, second, and third angle detecting means, and the arm attitude angle with respect to the horizontal plane and the preset target attitude angle. And a cylinder control means for controlling the arm driving cylinder so as to eliminate the deviation.