JPH11247217A - Working machine control device for construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform fine operation work without imposing a burden on an operator by detecting the height position of a working machine, and limiting the maximum rotating speed of a second front member to the specified value or less in the case of the detected height position being a specified height position or lower. SOLUTION: The height position of a working machine is detected by detecting the rotating angle of a first boom 5. In case of the detected height position of the working machine being a specified height position or lower, the maximum rotating speed of a second front member 11 is limited to the specified value or less. The working speed of a front member 7 to be a second boom is therefore limited to low speed of the specified value or less without fine adjustment of a second boom operating pedal 47 by a foot. An operator is therefore liberated from fine operation work of the second boom, while the working speed of the second boom is not limited to low speed when the working machine is in a high position, so that work efficiency can be heightened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work machine control device for a construction machine, and more particularly, to a work machine having a work machine including front members such as a boom, an arm, and a bucket provided in front of a vehicle body. The present invention relates to a device for controlling the driving of a vehicle.

[0002]

2. Description of the Related Art In a construction machine such as a hydraulic shovel, a multi-joint structure working machine including a plurality of front members is provided in front of a vehicle body. For example, in the case of a hydraulic excavator 1 as shown in FIG. 2, the first boom 5, the second boom 7, the offset boom 11, the arm 1
2. The buckets 14 are sequentially rotatably connected,
Excavation work and the like are performed by driving these work machines in accordance with operations performed by an operator using an operation lever or the like.

In the hydraulic excavator 1 having such a structure, the second
By operating the operation pedal or switch for the boom 7, the second boom 7 is rotated to perform a trench excavation operation, a mass excavation operation, and the like.

[0004] By the way, when performing a trench excavation work or the like, it is necessary to finely operate the second boom 7 so that the bucket 14 moves at a relatively low speed in the groove. Workability is improved by performing the operation of the second boom by a fine operation.

Therefore, conventionally, as an operator, by finely adjusting the operation amount of an operation pedal or the like for the second boom,
The bucket 14 is moved at a low speed in the groove while suppressing the operation speed of the second boom 7.

[0006]

However, the fine operation of moving the bucket 14 at a low speed in the groove by finely adjusting the operation pedal for the second boom with the foot requires a high level of skill, and Cost. In addition, this is all the more necessary in a situation where other operation levers such as an operation lever for a bucket other than the operation pedal for the second boom must be simultaneously operated.

[0007] For this reason, not only unskilled operators but also skilled operators have a heavy work load and large fatigue.

On the other hand, when the working machine is at a high position,
There is a demand for operating the second boom 7 quickly without requiring fine operation.

The present invention has been made in view of the above situation, and allows the operator to perform fine operation work such as digging work without losing workability when the working machine is at a high position. It is an object of the present invention to be able to perform the operation without burden.

[0010]

Means and Effects for Solving the Problems The first aspect of the present invention.
According to the present invention, in order to achieve the above-described solution, a first front member is disposed at the front of the vehicle body so as to be rotatable in the vertical direction, and is connected to the first front member so as to be rotatable in the vertical direction. A work machine control device for a construction machine, comprising: a work machine having at least a second front member; and controlling a rotation speed of the second front member according to an operation amount of an operation means. A height position detecting means for detecting a height position, and a maximum rotation of the second front member when the height position of the work implement detected by the height position detecting means is equal to or less than a predetermined height position. Control means for limiting the speed to a predetermined value or less.

According to the first invention, the height position of the working machine is
Specifically, it is detected by detecting the rotation angle θ1 of the first boom 5.

Then, as shown in FIG. 24, when the detected height position (first boom rotation angle θ1) of the working machine is below a predetermined height position Ha (not more than a predetermined angle θ1a),
The maximum operation speed of the second front member 11 is limited to a predetermined value or less.

Therefore, even if the second boom operation pedal is not finely adjusted by the foot, and even if the pedal is operated to the full stroke position, the operation speed of the second front member 7 as the second boom is maintained at a predetermined value. Limited to the following low speeds:

Therefore, the operator is freed from the work of finely operating the second boom operation pedal or the operation switch, and the work load and fatigue are reduced. On the other hand, when the work implement is at a high position, the operation speed of the second boom 7 is not limited to a low speed, so that work efficiency can be improved.

According to the second aspect of the present invention, the first front member is disposed at the front of the vehicle body so as to be rotatable in the vertical direction, and the first front member is rotatably connected to the first front member in the vertical direction. A work machine control device for a construction machine, comprising: a work machine having at least a second front member, and controlling a rotation speed of the second front member according to an operation amount of an operation means. A height position detecting means for detecting a position, and a maximum rotation speed of the second front member when the height position of the work implement is equal to or less than a predetermined height position, wherein the height position of the work implement is Correspondence of the maximum rotation speed of the second front member to the height position of the work implement so as to be smaller than the maximum rotation speed of the second front member when it is larger than the predetermined height position Set hands to set relationships And a maximum rotation speed of the second front member corresponding to the height position of the work implement detected by the height position detection means is obtained from the content set by the setting means, and the obtained maximum rotation speed is obtained. Control means for controlling the rotation speed of the second front member within a range not higher than the dynamic speed.

According to the second aspect, the same effects as those of the first aspect can be obtained.

However, in the second invention, as shown in FIG. 24, the second front when the height position of the work implement is equal to or less than a predetermined height position (the first boom rotation angle θ1 is equal to or less than θ1a). Maximum operating speed of the member 7 (from less than 100% to 60%
The maximum operating speed of the second front member 7 when the height position of the work implement is larger than the predetermined height position (when the first boom rotation angle θ1 is larger than θ1a) (100). % Speed), the maximum operating speed of the second front member 7 corresponding to the height position of the work implement (first boom rotation angle θ1) is set.

Therefore, the second front member 7 corresponding to the detected height position of the working machine (the first boom rotation angle θ1).
The maximum operation speed of is obtained from the above set contents,
The offset operation of the second front member 7 is performed within a range equal to or less than the obtained maximum operation speed.

According to the third aspect of the present invention, the first front member is disposed at the front of the vehicle body so as to be rotatable in the vertical direction, and the first front member is rotatably connected to the first front member so as to be rotatable in the vertical direction. A work machine control device for a construction machine, comprising: a work machine having at least a second front member, and controlling a rotation speed of the second front member according to an operation amount of an operation means. Height position detection means for detecting a position, operation amount detection means for detecting the operation amount of the operation means, and the second front member when the height position of the work implement is equal to or less than a predetermined height position Height of the work implement so that the maximum rotational speed of the work implement is smaller than the maximum rotational speed of the second front member when the height position of the work implement is higher than the predetermined height position. Said second flow to a position First setting means for setting a first correspondence between the maximum rotation speeds of the first member and second setting for setting a second correspondence between the rotation speed of the second front member and the operation amount of the operation means. 2 setting means, and the maximum rotation speed of the second front member corresponding to the current height position of the work implement detected by the height position detection means is obtained from the first correspondence, A rotation speed of the second front member corresponding to a current operation amount of the operation means detected by the operation amount detection means is obtained from the second correspondence, and a smaller one of the obtained rotation speeds. Control means for controlling the rotation speed of the second front member so that the rotation speed of the second front member can be obtained.

In the third aspect of the present invention, as shown in FIG. 24, the second front member 7 when the height position of the work implement is equal to or less than a predetermined height position (the first boom rotation angle θ1 is equal to or less than θ1a). The maximum operating speed (speed from less than 100% to 60%) of the work machine when the height position of the work implement is larger than the predetermined height position (when the first boom rotation angle θ1 is larger than θ1a) 2 the maximum operating speed of the front member 7 (1
(A speed of 00%), a first correspondence relationship between the maximum operating speed of the second front member 7 and the height position (first boom rotation angle θ1) of the work implement is set. .

On the other hand, as shown in FIGS. 25A and 25B, the operating means 45U,
A second correspondence relationship between the operation amount St of 5D and the operation speed (flow rate command) of the second front member 7 is set. The operation amount St of the operation means 45U and 45D is detected.

Therefore, the maximum operating speed of the second front member 7 corresponding to the detected current height position of the working machine (first boom rotation angle θ1) is determined by the first correspondence (see FIG. 24), the operation speed of the second front member 7 corresponding to the detected current operation amount St is determined by the second correspondence (FIGS. 25A and 25B).
The second front member 7 is operated such that the smaller one of the obtained operation speeds is obtained (FIGS. 26A and 26B).

For this reason, as shown in FIG. 27, the second front member 7 serving as the second boom is provided with the operating means 45U when the height position of the working machine is low and the digging work is performed. , 45D, regardless of the operation amount St of the operation device, the operation speed is reduced (speed veD), and when the height position of the work implement is high, the speed (speed v) corresponding to the operation amount St of the operation means 45U, 45D ( The second boom 7 is operated at a high speed at a speed veU (> veD).

[0024]

Embodiments of the present invention will be described below.

FIG. 1 shows the overall configuration of a working machine control device for a construction machine according to this embodiment. FIG. 2 shows the appearance of a hydraulic shovel assumed as a construction machine in the present embodiment.

FIG. 2A is a side view of a hydraulic excavator provided with an offset boom, and FIG. 2B is a side view of FIG.
FIG.

As shown in FIG. 2, this excavator 1
A lower traveling body 2 that travels by rotating a crawler belt by a traveling motor (not shown) and an upper part that is disposed above the lower traveling body 2 via a swing circle 4 and that is turned by a turning motor (not shown) Revolving superstructure 3 (vehicle body 3), first boom 5, second boom 7, offset boom 11, arm 1
2, a work machine comprising the front members of the bucket 14. In the cab of the upper revolving superstructure 3, FIG.
As shown in the figure, an operation panel 25 having a monitor for instructing the operation content and displaying the vehicle operation status, a left and right operation lever 45 for operating the driving of each front member of the work machine,
46, operation switches 46U and 46D, and an offset boom operation pedal (offset pedal) 47 are arranged.

This work machine is configured such that a first boom 5, a second boom 7, an offset boom 11, an arm 1
2. The bucket 14 is configured to be sequentially connected.

The first boom 5 is disposed on a vehicle body turning frame of the vehicle body 3 so as to be vertically rotatable about a boom foot 5a. The second boom 7 is disposed at the tip of the first boom 5 so as to be rotatable up and down around the first boom top pin. Similarly, arm 1
2 is disposed on the bracket 9 via a second boom 7, an offset boom 11 and a bracket 9 so as to be rotatable in a vertical direction.
It is arranged so as to be rotatable in the vertical direction.

The first boom hydraulic cylinder 6 is a hydraulic actuator for driving the first boom 5, and the bottom side of the first boom hydraulic cylinder 6 is disposed on the vehicle body 3.
The rod tip is disposed on the upper end of the first boom 5. Therefore, when pressure oil is supplied to the bottom chamber of the first boom hydraulic cylinder 6, the rod is extended, and when pressure oil is supplied to the head chamber, the rod is retracted. 5 is turned upward or downward.

Similarly, with respect to the second boom hydraulic cylinder 8 for driving the second boom 7, the bottom side of the second boom hydraulic cylinder 8 is disposed on the first boom 5, and the rod end thereof is connected to the second boom 7. At the end of the second
By supplying pressure oil to the bottom chamber or the head chamber of the boom hydraulic cylinder 8, the rod is extended or retracted,
In response, the second boom 7 is rotated downward or upward.

As shown in FIG. 1, the pressure P1h of the pressure oil in the head chamber of the first boom hydraulic cylinder 6 is
1 and input to the controller 50. Similarly, the bottom chamber pressure of the first boom hydraulic cylinder 6,
The pressure in the head chamber and the pressure in the bottom chamber of the second boom hydraulic cylinder 8 are detected by pressure sensors 22, 23, and 243, respectively, and input to the controller 50.

The arm hydraulic cylinder 13 for driving the arm 12 is supported by a bracket 9 provided at the tip of the offset boom 11, and its rod tip is connected to the arm 1.
The arm 12 is turned in the excavation direction or the dumping direction when the rod of the arm hydraulic cylinder 13 is driven to extend or retract.

The bottom side of a bucket hydraulic cylinder 15 for driving the bucket 14 is disposed on the arm 12, and the rod tip is disposed on the bucket 14 via links 15a and 15b. Hydraulic cylinder for bucket 1
The bucket 14 is rotated in the digging direction or the dumping direction by driving the telescopic drive 5 or the retractable drive.

FIG. 2B shows a state in which the arm 12 is offset in the left-right direction of the vehicle body 3 with respect to the second boom 7 by rotating the offset boom 11 right and left (referred to as an offset operation). ing.

That is, one end of the offset boom 11 is rotatably disposed on the second boom 7, and the other end is connected to the arm 12 via the bracket 9. The bottom side of the offset boom hydraulic cylinder 10 that drives the offset boom 11 is disposed on the second boom 7, and the rod end thereof is disposed on the bracket 9.
The rod 11a is a rod provided so that the posture of the bracket 9 (arm 12) with respect to the second boom 7 does not change with the offset operation, and one end of the rod 11a is disposed on the second boom 7 and the other end. Are disposed on the bracket 9. Therefore, when the offset boom hydraulic cylinder 10 is driven to extend or retract, the offset boom 11 is rotated rightward or leftward, and the arm 12 is moved rightward or leftward with respect to the second boom 7. It is offset by an offset amount corresponding to the rotation amount. A two-dot chain line in FIG. 2B shows a state when the offset boom 11 is offset rightward. The rotation angle θ3 of the offset boom 11 with respect to the second boom 7 is detected by the offset boom rotation angle sensor 16 as the offset angle θ3, and is input to the controller 50.

FIG. 3 shows only the working machine of the hydraulic excavator 1 shown in FIG. 2 and shows its geometric relationship. FIGS. 3A and 3B correspond to FIGS. 2A and 2B, respectively.

The origin O of the XYZ coordinate system is set at the position of the boom foot 5a. The polarity of the rotation angle θ1 of the first boom 5 with respect to the vehicle body 3 (the first boom rotation angle θ1) is + when the first boom 5 is turned upward,
It is defined as-when turned downward. The first boom rotation angle θ1 is detected by the first boom rotation angle sensor 17. Similarly, the rotation angle θ2 of the second boom 7 with respect to the first boom 5 (second boom rotation angle θ2) is detected by the rotation angle sensor 18 for the second boom, and the rotation angle θ4 of the arm 12 with respect to the offset boom 11 (arm The rotation angle θ 4) is detected by the arm rotation angle sensor 19. The detected rotation angles of these rotation angle sensors 17, 18, 19 are input to the controller 50. The rotation angle sensors 16 to 19 are, for example, potentiometers.

In FIG. 3, a represents the second boom 7 and the first boom.
B is the position of the first boom top pin connecting the boom 5; b is the position of the second boom top pin connecting the offset boom 11 and the second boom 7;
The position of the offset boom top pin connecting the bracket 9 and the offset boom 11 is indicated by d.
Is a position where a bracket top pin (arm bottom pin) for connecting the bracket 14 and the bracket 9 is provided.
This is a position where an arm top pin 12a (hereinafter simply referred to as an arm top 12a) for connecting the arm 12 is disposed.

Therefore, the length L1 of the first boom 5 is represented by the length of a line connecting the boom foot 5a and the point a, and the length L22 (second boom length 2) of the second boom 7 in the vertical direction is calculated as follows. The horizontal length L21 of the second boom 7 (the second boom length 1) is represented by the horizontal distance between the points a and b, and the length of the offset boom 11 is represented by the vertical distance between the points a and b. L3 is b
The length L4 (third bracket length) of the bracket 9 is represented by the length of a line segment connecting the point and the point c, the length of the line segment connecting the point c and the point d, and the length L5 of the arm 12 is represented by , D, and e. The bucket blade position 14a is the position of the tip of the entire work machine (see FIG. 1).

The angle γ formed by the line segment de (arm 12) with respect to the line segment perpendicular to the arm bottom d point is
The arm-to-ground angle γ is defined. The arm-ground angle γ indicates the posture of the arm 12.

Then, the coordinate position e (X5, Y5, Z5) of these arm tops 12a is determined by the rotation angles θ1, θ2, θ
3, given θ4, each known length L1, L21, L2
Using L2, L3, L4, and L5, the following arithmetic expressions (1) to (1)
As shown in 1), it is uniquely determined.

For the arm-to-ground angle γ, given the rotation angles θ1, θ2, θ4, the following equation (1)
As shown in 2), it is uniquely determined.

The bucket width l, floor distance s, and wrist radius r of the bucket 14 are also known. When the rotation angle of the bucket 14 is further given, the coordinate position e (X5, Y5, By using Z5), the coordinate position (X6, Y6, Z6) of the working machine tip 14a is uniquely determined. In addition, ignoring the rotation angle of the bucket 14 (assuming that the bucket 14 is in a fixed state), the coordinate position e (X5, Y5, Z5) of the arm top 12a and the coordinate position (X6 , Y6, Z6).

An arithmetic expression for calculating the coordinate positions of the points a to e and the arm-to-ground angle γ in FIG. 3 will be described below with reference to the table shown in FIG.

First, the coordinate position of the foot 5a (origin 0) of the first boom 5 is set to X0 = 0, Y0 = 0, and Z0 = 0.

Then, the X, Y, Z coordinate positions of the top (point a) of the first boom 5 are as follows: X1 = L1 × Cos θ1 (1) Y1 = L1 × Sin θ1 (2) Z1 = 0 .

Then, the X, Y and Z coordinate positions of the top (point b) of the second boom 7 are as follows: X2 = X1 + L22 × Sin (θ1 + θ2) −L21 × Cos (θ1 + θ2) (3) Y2 = Y1−L22 × Cos (θ1 + θ2) −L21 × Sin (θ1 + θ2) (4) Z2 = 0.

Then, the X, Y, and Z coordinate positions of the top (point c) of the offset boom 11 are as follows: X3 = X2-L3 Cos θ3 × Cos (θ1 + θ2) (5) Y3 = Y2-L3 Cos θ3 × Sin ( θ1 + θ2) (6) Z3 = L3 × Sin θ3 (7)

Then, the X, Y, Z coordinate positions of the top (point d of the arm bottom) of the bracket 9 are as follows: X4 = X3−L4 × Cos (θ1 + θ2) (8) Y4 = Y3−L4 × Sin (θ1 + θ2) (9) Z4 = Z3.

Then, the top 12a (e) of the arm 12
The X, Y, and Z coordinate positions of the point) are as follows: X5 = X4 + L5 × Cos (θ1 + θ2 + θ4) (10) Y5 = Y4 + L5 × Sin (θ1 + θ2 + θ4) (11) Z5 = Z3

On the other hand, the arm-to-ground angle γ is expressed as follows: γ = θ1 + θ2 + θ4-270 ((12)

As described above, when the rotation angles θ1 to θ4 of the working machine are given, the coordinate positions of the arm top 12a of the excavator 1 are calculated by using the known lengths and the above equations (1) to (11). X5, Y5, Z5) can be uniquely obtained, and from this, the coordinate position (X6, Y6, Z6) of the work implement tip 14a can be uniquely obtained. In addition, the rotation angle θ of the working machine
Given 1, θ2 and θ4, the arm-to-ground angle γ can be uniquely obtained. θ1 to θ4 are the rotation angle sensors 1
7, 18, 16, and 19 are provided as detection values.

In this embodiment, when the rotation angle θ1 of the first boom 5 is changed by operating the operation lever, the coordinate position (X6, Y6,
Z6) (Coordinate position of arm top 12a (X5, Y5, Z5))
Is to control the rotation angle θ2 of the second boom 7 so as to be on the target line.

That is, in the memory of the controller 50 shown in FIG. 1, the length L1 of the first boom 5, the length L21, L22 of the second boom 7, the length L3 of the offset boom 11,
Known values such as the length L4 of the bracket 9 and the length L5 of the arm 12 are stored, and an arithmetic expression for calculating the coordinate position of each of the points a to e and a functional expression of the arm-to-ground angle γ are stored. Based on these stored contents, the controller 50 controls the second boom rotation angle θ2 so that the work implement tip 14a moves along a desired line.

In this embodiment, the hydraulic excavator 1 having the offset boom 11 is assumed, but the present invention is also applicable to the hydraulic excavator 1 shown in FIG.

The hydraulic excavator 1 also has a lower traveling body 2 that travels when a crawler belt is rotated by a traveling motor (not shown), and a swing circle 4 above the lower traveling body 2, similarly to FIG. 2. Revolving superstructure 3 (vehicle body 3) which is arranged in a horizontal position and is revolved by a revolving motor (not shown)
And a working machine which is mounted on the front of the vehicle body 3 and includes front members of a first boom 5A, a second boom 7A, an arm 12A and a bucket 14.

This work machine is configured such that a first boom 5A, a second boom 7A, a fixed work machine link 7B, an arm 12A, and a bucket 14 are sequentially connected to the vehicle body 3. The difference from FIG. 2 is that a fixed work implement link 7B is used instead of the offset boom 11. Therefore, the second boom 7A and the arm 12A are connected via the work implement link 7B.
The arm 12A is not offset in the left-right direction with respect to A.

The first boom hydraulic cylinder 6A allows the first
The boom 5A is driven, and the second boom hydraulic cylinder 8A
Drives the second boom 7A, the arm hydraulic cylinder 13A drives the arm 12A, and the first boom 5A
The point that A is rotated at a rotation angle θ1, the second boom 7A is rotated at a rotation angle θ2, and the arm 12A is rotated at a rotation angle θ4 is the same as the hydraulic excavator shown in FIG.

Therefore, by giving the rotation angles θ1, θ2 and θ4 in the same manner as in FIGS. 3 and 4, the coordinate position of the working machine tip 14a can be obtained by calculation. The second boom rotation angle θ2 can be controlled so that the tip 14a moves along a desired line.

Next, the configuration of the work machine control device will be described with reference to FIG.

That is, as shown in FIG. 1, the work machine control device is mainly composed of an engine 31 and driven by the engine 31, and each of the hydraulic cylinders 6, 8, 1
A variable displacement hydraulic pump 1 that discharges pressure oil for driving 0 and 13; a pilot pump 33 that is driven by the engine 31 and discharges pressure oil for a pilot; an operation lever 46; operation buttons 46U and 46D; The opening area is changed in accordance with the operation of the operation pedal 47 and the operation lever 45, whereby the flow rate of the hydraulic oil discharged from the hydraulic pump 32 is controlled, and the hydraulic oil whose flow rate is controlled is supplied to each hydraulic actuator 6, Flow control valves 3 to be supplied to 8, 10 and 13, respectively
4, 35, 36, 37 and the rotation speed Ne of the engine 31
(R / min) engine speed sensor 27
And an operation panel 25 having a monitor function for displaying the state of the device on a screen, and the rotation angle sensors 17, 18, and 1.
6, 19 indicating the detected rotational angles θ1, θ2, θ3, θ4, signals indicating the detected pressures P1h of the pressure sensors 21 to 24, signals indicating the detected rotational speed Ne of the engine rotational speed sensor 27, and operations Lever 46, operation buttons 46U, 46D,
Signals V1, V2, V3, and V4 indicating the operation amounts (operation strokes) of the operation pedal 47 and the operation lever 45 are input, and based on these signals, the flow control valves 34, 35, 36, and 37 are respectively driven and controlled. Command currents I1, I2, I3,
Controller 5 that outputs I4 and outputs a command current for sounding (or lighting) alarm 28
0. A functional block diagram of the controller 50 is shown in FIG. 13 as described later. In the drawings, a mechanism for driving the bucket 14, a mechanism for turning the upper swing body 3, and a mechanism for running the lower running body 2 are omitted because they are not directly related to the gist of the present invention. .

A more specific description will be given.

FIG. 6A shows the arrangement of the operation levers 45 and 46 in the cab of the excavator 1. Left and right operation levers 45 and 46 are provided at the front of the seat 48 on which the operator sits, and different front members can be operated by one operation lever.

That is, as shown by arrows in FIG. 6A, the arm 12 is operated in the dumping direction and the arm 12 is operated in the excavation direction in response to the forward operation or the backward operation of the left operation lever 45. Is done. Then, in response to the leftward operation or the rightward operation of the same left operation lever 45, the upper swing body 3 is operated in the left swing direction, and the upper swing body 3 is operated in the right swing direction. Similarly, the first boom 5 is operated in the upward direction and in the downward direction in response to the forward operation or the backward operation of the right operation lever 46, so that the same right operation lever 46 can be operated leftward or rightward. Accordingly, the bucket 14 is operated in the digging direction and the dumping direction (FIG. 6).
(B)).

As shown in FIG. 6B, the right operation lever 4
Operation buttons 46U and 46D are arranged above the knob 46N of No. 6. These operation buttons 46U and 46D are switches for instructing the second boom 7 to rotate upward and downward, and when the operation button 46U is pressed, the amount of the press operation (pressed amount) The second boom 7 is actuated upward by an amount corresponding to the number of times and the time of pressing. Similarly, when the operation button 46D is pressed, the second boom 7 is operated downward by an amount corresponding to the amount of the pressing operation.

Since the button for operating the second boom 7 is provided above the operation lever 46 for operating the first boom 5, the second boom 7 is operated while operating the first boom 5.
Is quickly and easily performed, and operability is improved. The right operation lever 46 has the operation buttons 46
In addition to the buttons U and 46D, buttons for instructing other operations are provided. The same applies to the left operation lever 45.

Operation pedal 47 as offset pedal
Are provided on the left and right sides of the driver's seat 48, and the offset boom 11 is operated left and right according to the respective operation amounts (stepping amounts).

The operation lever 46 is an electric lever, and the operation stroke amount when the first boom 5 is operated by the operation lever 46 is input to the controller 50 as an electric signal V1. Similarly, an electric signal V2 indicating the operation amount of the operation buttons 46U and 46D, an electric signal V3 indicating the depression amount of the operation pedal 47, and an electric signal V4 indicating the operation amount when the arm 12 is operated by the operation lever 45 are: Each is input to the controller 50.

A signal V1 indicating the operation amount of the operation lever 46
Is converted by the controller 50 into a command current I1 for the flow control valve 34, which is applied to the electromagnetic proportional control valve 38 or 39. Pilot pressure oil discharged from the pilot pump 33 is supplied to these electromagnetic proportional valves 38 and 39 via a pilot line 41. The pilot pressure oil controlled by the electromagnetic proportional valve 38 or 39 is applied as a pilot signal to the input port 34a or 34b of the flow control valve 34 via the pilot line 41 or 42.

When the operation amount V1 indicates the polarity (+) indicating the upward direction of the first boom 5, the command current I1 is applied to the electromagnetic proportional control valve 38, and the operation amount V1 is decreased in the downward direction of the first boom 5. When the polarity (-) indicating
The command current I1 is applied to the electromagnetic proportional control valve 39.

For example, when the operation lever 46 is operated in the direction of raising the first boom 5, the command current I
1 is added to the electromagnetic proportional control valve 38. At the electromagnetic proportional control valve 38, the command current I1 is converted into a pilot pressure, and pilot pressure oil having a pilot pressure corresponding to the command current I1 is applied to the input port 34a of the flow control valve 34. As a result, the spool of the flow control valve 34 is driven leftward,
When the pressure oil is supplied to the bottom chamber side of the hydraulic cylinder 6, the first boom 5 is rotated upward at a speed corresponding to the operation amount of the operation lever 46. Similarly, the operation lever 4
When the first boom 5 is operated to lower the first boom 5, the command current I 1 is converted into a pilot pressure by the electromagnetic proportional control valve 39, and the first boom 5 is moved at a speed corresponding to the operation amount of the operation lever 46. It is turned downward.

Similarly, an electric signal V2 indicating the amount of operation of the operation buttons 46U and 46D is converted into a command current I2 by the controller 50, and the flow control valve 35 is driven via an electromagnetic proportional control valve (not shown). The second boom 7 is turned up and down via the hydraulic cylinder 8. Similarly, an electric signal V3 indicating the depression amount of the operation pedal 47 is converted into a command current I3 by the controller 50, the flow control valve 36 is driven via an electromagnetic proportional control valve (not shown), and the offset is output via the hydraulic cylinder 10. The boom 11 is rotated left and right.

Similarly, an electric signal V4 indicating an operation amount when the arm 12 is operated by the operation lever 45 is converted into a command current I4 by the controller 50, and the electric current V4 is supplied to the flow control valve 37 via an electromagnetic proportional control valve (not shown). Drive the hydraulic cylinder 13
The arm 12 is turned up and down via the.

The operation panel 25 controls the driving of the second boom 7
The “auto mode” for automatically controlling the first boom 5 in accordance with the rotation angle θ1 and the driving of the second boom 7
Automatically selects and switches to "manual mode" to control manually regardless of the rotation angle θ1 of the boom 5
A / manual mode changeover switch 26 is provided. The switch 26 includes a mode changeover switch 26 a for selecting various operation modes including “auto mode”, and a switch 26.
Set the mode selected / released in a /
And a release switch 26b. When "automatic mode" is selected by the mode switch 26a and "setting" is selected by the mode setting / cancellation switch 26b,
A signal instructing the “auto mode” is input to the controller 50. "Automatic mode" with the mode switch 26a
Is selected and "release" is selected by the mode setting / release switch 26b, "auto mode" is released, and a signal instructing "manual mode" is input to the controller 50. The controller 50 executes control according to either the input “auto mode” instruction signal or the “manual mode” instruction signal.

Next, the control contents of the "auto mode" performed by the controller 50 will be described.

First Control (Automatic Control of Second Boom Rotation Angle θ2 According to First Boom Rotation Angle θ1) FIG. 7 is a side view showing a working radius of the excavator 1.

In FIG. 7, the curve a represents the working machine tip 14a (bucket) when the second boom rotation angle θ2 is the maximum angle (the first boom rotation angle θ1 and the arm rotation angle θ4 are also the maximum angles). 2 shows the movement locus of the cutting edge.
At this time, the locus a draws an arc-shaped locus, and the excavator 1
Has the largest working radius and the largest working range.

A curve b indicates the locus of the movement of the arm top 12a when the tip 14a of the working machine draws the locus a of the maximum working radius. At this time, the locus b draws an arc-shaped locus.

However, when the working machine tip 14a and the arm top 12a move along the trajectories a and b, the hydraulic excavator 1 has a large overturning moment, and is highly likely to overturn.

A curve c indicates the movement locus of the arm top 12a at the limit where the excavator 1 does not fall. If the arm top 12a is positioned ahead of the locus c, the excavator 1 may fall down due to an increase in the overturning moment.

The curve d from the point C to the point B represents the working machine tip 14a when the arm top 12a draws the locus c.
Indicates the trajectory of the movement. At this time, the locus d draws an arc-shaped locus. The point C is a position where the first boom hydraulic cylinder 6 reaches the stroke end on the rod extension side.

When the working machine tip 14a moves along the trajectory d, work such as excavation at a high place can be performed with a maximum working range within a range where the excavator 1 is stable.

In the hydraulic excavator 1, there is a case where a work machine is extended forward to perform a trench excavation operation, a mass excavation operation, or the like. Such work must be performed not only to stabilize the hydraulic excavator 1 so that it does not fall over, but also to linearly move the work implement tip 14a vertically in front of the vehicle body 3.

A straight line e from the point B to the point A, which is continuous with the curve d, shows the movement locus of the working machine tip 14a when performing a trench excavation operation, a mass excavation operation, or the like.

When the working machine tip 14a moves along the trajectory e, the work can be performed with a maximum working range within a range where the hydraulic excavator 1 is stable.

A curve g from the point A to the point D, which is continuous with the straight line e, indicates the movement locus of the working machine tip 14a when performing a trench excavation work, a mass excavation work, or the like. This locus g draws an arc-shaped locus. When excavating a hole or the like below the ground surface GL, the working machine tip 14a draws this locus g. In addition,
Point D is a position where the first boom hydraulic cylinder 6 reaches the stroke end on the rod retracting side.

When the working machine tip 14a moves along the trajectory g, the work can be performed with the maximum working range within which the hydraulic excavator 1 is stable.

In the present embodiment, the second boom rotation angle θ2 is controlled so that the working machine tip 14a moves along a locus including such a curve d, a straight line e, and a curve g (referred to as a reference line R1). Things.

FIG. 8 is a diagram exemplifying a work site. The work for forming the groove HL can be easily performed by moving the working machine tip 14a along the reference line R1.
In some cases, it may be preferable to move the working machine tip 14a along different lines R2 and R3 depending on the working mode. However, to prevent the vehicle from tipping over,
2 and R3 also need not be located ahead (as viewed from the vehicle body) of the reference line R1.

FIG. 9 shows the reference line R shown in FIG. 7 or FIG.
6 is a graph showing the correspondence between the first boom rotation angle θ1 and the second boom rotation angle θ2 when the work implement tip 14a moves in FIG.

The line S1 indicating the correspondence can be obtained by the above-mentioned arithmetic expressions (1) to (11).

That is, when the reference line R1 is determined, the coordinate position (X6, Y6, Z6) of the tip 14a of the working machine is determined, whereby the coordinate position (X5, Y5, Z5) of the arm top 12a is determined.
5) is determined. Therefore, if the arm rotation angle θ4 and the offset boom rotation angle θ3 are fixed, the second boom rotation angle θ2 corresponding to the first boom rotation angle θ1 can be uniquely obtained. In this manner, the correspondence S1 between the first boom rotation angle θ1 and the second boom rotation angle θ2 is obtained. The controller 50 performs a process of creating the correspondence S1 based on the stored data of the known first boom length L1 and the like, and uses the created correspondence S1 as a reference line diagram S1 of the “first” of the controller 50. Target second boom angle reference diagram memory 58 for boom angle "(FIG. 13).

In this case, the correspondence S1 may be stored in the form of a storage table so that θ2 can be immediately read out when θ1 is given, and the correspondence S1 is given using the function θ2 = f (θ1). The function θ2 = f (θ1) may be stored so that θ2 can be calculated from the obtained θ1.

In the controller 50, as described later,
Current first boom rotation angle θ detected by rotation angle sensor 17
The second boom target rotation angle θ2 corresponding to 1 is obtained by reading out or calculating from the stored correspondence S1,
The rotation angle sensor 1 is set so that the target rotation angle θ2 is obtained.
Drive control is performed using the current second boom rotation angle θ2 detected in step 7 as a feedback amount. That is, the target rotation angle θ
The current command I2 is output so that the deviation θd between 2r and the current rotation angle θ2 becomes zero, and the rotation of the second boom 7 is controlled.

Therefore, as an operator, the arm rotation angle θ4 is fixed to the maximum angle, and the offset boom rotation angle θ3
Is fixed at a predetermined offset angle θ3,
Only by manually operating the drive of the first boom 5 with the operation lever 46, the second boom 7 is automatically driven.
), The working machine tip 14a can be moved along the reference line R1. Thereby, a trench excavation work, a mass excavation work, and the like can be easily performed.

The sections θD to θA of the first boom rotation angle θ1 in FIG. 9 correspond to the sections D to A of the trajectory g of the working machine tip 14a in FIG. 7, and the sections of the first boom rotation angle θ1 in FIG. θA to θB are the working machine tip 14 in FIG.
9 corresponds to the sections A to B of the trajectory e of FIG. 9, and the sections θB to θC of the first boom rotation angle θ1 in FIG. 9 correspond to the sections B to C of the trajectory d of the work implement tip 14a in FIG. .

In the sections θD to θA of FIG. 9, the second boom rotation angle θ2 is the maximum value θ2max (the rod retraction-side stroke end position of the second boom hydraulic cylinder 8), as shown in FIG. The working machine tip 14a is farthest from the vehicle body 3, and it is possible to excavate the farthest position and the deepest position.

Next, in the section θA to θB of FIG. 9, the second boom rotation angle θ2 gradually decreases as the first boom rotation angle θ1 increases, and as shown in FIG.
Can move along the vertical straight line e to form the wall of the groove HL in a straight line (see FIG. 8). If the second boom rotation angle θ2 is kept at the maximum value θ2max irrespective of the increase of the first boom rotation angle θ1, the work implement tip 1
This is because 4a moves along the curve a, so that the stability of the vehicle body is not ensured and the working efficiency is reduced.

Next, in the section θB to θC of FIG. 9, the second boom rotation angle θ2 gradually increases with the increase of the first boom rotation angle θ1, and as shown in FIG.
Can excavate the most distant position within a range in which the vehicle body is stable. If the second boom rotation angle θ2 is not increased even if the first boom rotation angle θ1 increases, the working machine tip 14a will move along the curve f, and the working range will be narrowed, This is because the work efficiency when excavating at a high place is reduced.

As described above, along with the correspondence S1, the second
By controlling the boom rotation angle θ2, a maximum working range can be secured within a range where the vehicle body is stabilized, and work can be performed safely and efficiently.

As described above, when the working machine of the excavator 1 is extended forward to perform a trench excavation work, a mass digging work, or the like, the operating machine tip 14a can be moved only by operating one operating lever 46. Since the excavator 1 is automatically moved along the linear trajectory e within a range in which the vehicle body is stabilized, the hydraulic excavator 1 can be stabilized and not fall down. Even if the operation requires a complicated complex operation of moving up and down linearly, the operator's burden and labor are dramatically reduced without requiring skill. Also, when working on a narrow land, even if there are obstacles such as telephone poles and building walls in the front, once the working machine tip 14a is located in front of these obstacles, the working machine will be moved from that position. Tip 14
a can be automatically moved along a linear trajectory e in the vertical direction. Therefore, it is necessary to always pay attention to the work implement tip 14a interfering with obstacles and operate the movement of the work implement tip. Disappears. For this reason, it is possible to concentrate on the operation of the work machine without paying attention to the obstacle, and the work efficiency is improved, and the work is safely performed without the work machine tip 14a interfering with the obstacle.

In addition to the line S1 corresponding to the reference line R1 in FIG. 8, a line S2 corresponding to the line R2 in FIG. 8 and a line S3 corresponding to the line R3 in FIG.
It may be stored and stored in the memory 58 of the controller 50.

Sections θE to θF of line S2 in FIG.
Correspond to the sections EF of the line R2 in FIG. 8, and the sections θF to θC ′ of the line S2 in FIG. 9 correspond to the sections FC to C ′ of the line R2 in FIG.

In the section θG of the line S3 in FIG.
θF corresponds to the sections GF of the line R3 in FIG.
The sections θF to θC ′ of the line S3 in FIG.
Corresponds to the sections F to C 'of the line R3.

The lines S1, S2, and S3 are stored in the memory 58, and the line closest to the current position of the tip 14a of the work machine is selected from these lines, and the second boom rotation is performed along the selected line. The angle θ2 may be controlled, and one of the lines S2 and S3 is stored in the memory 58,
The second boom rotation angle θ2 may be controlled along the stored line.

Further, the working machine tip line R having a different shape is used.
Instead of setting the lines S1, S2, S3 corresponding to 1, R2, R3, respectively, they correspond to the working machine tip lines R1, R4, R5, R6 having the same shape as the reference line R1 as shown in FIG. The lines S1, S4, S5, and S6 to be used may be stored in the memory 58 as shown in FIG. The working machine tip lines R4, R5, and R6 are lines obtained by sequentially moving the reference line R1 in parallel to the vehicle body 3 as shown in FIG.
The lines S4, S5, and S6 shown in FIG. 10 can be obtained by sequentially translating the reference line S1 downward in parallel. However, the line S cannot be set when the second boom rotation angle θ2 is lower than the minimum angle θ2min (stroke end position of the rod of the second boom hydraulic cylinder 8 on the extension side).

In this case, lines S1, S4,
S5 and S6 may be stored, a line closest to the current position of the work implement tip 14a may be selected from these lines, and the second boom rotation angle θ2 may be controlled along the selected line. Any one of the lines S4, S5 and S6 is stored in the memory 58, and the second line is stored along the stored line.
The boom rotation angle θ2 may be controlled.

FIG. 11 shows that the working machine tip 14 is stored in the memory 58.
The reference line S1 corresponding to the reference line R1 of the work machine a is stored, and the reference line S1 is translated downward, so that the line S1 corresponding to the work machine tip line R passing the current position of the work machine tip 14a is stored. Is shown.

Hereinafter, the contents of the processing will be described with reference to the functional block diagram of the controller 50 shown in FIG. 13 and the flowchart shown in FIG.

In step 101 shown in FIG. 16, first,
By switching operation of the automatic / manual mode switch 26,
It is determined whether "automatic mode" or "manual mode" has been selected. If it is determined that the "auto mode" has been selected (determination YES in step 101), then it is determined whether or not the operation buttons 46U and 46D have been operated, that is, whether or not the second boom 7 has been manually operated. (Step 102).

If it is determined that the second boom 7 has not been manually operated (NO in step 102), then it is determined whether or not the operation buttons 46U and 46D have just been operated, that is, the second operation has been completed. It is determined whether or not the boom 7 has just been manually operated (step 103).

Here, at the start of the "auto mode", the first
In order to obtain the initial values of the rotation angles θ1 and θ2 of the boom 5 and the second boom 7, the controller 50 executes steps 107 to 109 at the time of startup.

After that, the first boom 5 is manually operated.
If the second boom 7 has not been manually operated yet, the determination in step 103 is NO, and the procedure proceeds to step 106.

For example, the initial values of the rotation angles θ1 and θ2 of the first boom 5 and the second boom 7 are changed to the angle θ1 on the reference line S1.
If s and θ2s, the process of automatically controlling the second boom 7 is executed according to the reference line S1 stored in the memory 58 shown in FIG.

That is, in FIG. 13, the controller 50 receives the first boom rotation angle detection signal and the second boom rotation angle detection signal from the rotation angle sensors 17 and 18 as voltage values. The 2 boom angle calculation unit 51 calculates the first boom rotation angle θ1 and the second boom rotation angle θ2 by performing processing such as converting the voltage value into engineering units.

Now, the operation lever 46 is operated by a predetermined amount from the neutral position, and the operation amount signal V1 is output from the controller 50.
, The first boom operation valve command calculation unit 5
In step 4, a command I1 corresponding to the manipulated variable V1 is calculated, and the current output unit 57 outputs the command current I1 to the electromagnetic proportional control valve 38 or 39 corresponding to the first boom flow control valve 34. As a result, the first boom 5 is rotated upward or downward at a speed corresponding to the operation amount V1 of the operation lever 46.

On the other hand, the difference calculation section 52 between the second boom angle and the target second boom angle calculates the second boom rotation angle θ1 corresponding to the current first boom rotation angle θ1 obtained from the detection result of the sensor 17 by the calculation section 51. A process for obtaining the boom target rotation angle θ2r from the correspondence S1 stored in the memory 58 is executed.

That is, as shown in FIG. 11, when the current first boom rotation angle θ1 is θ1s, the first
The second boom angle θ2s corresponding to the boom angle θ1s is read from the storage table of the correspondence S1 as the second boom target rotation angle θ2r.

Therefore, the compensation element calculating section 53 quickly sets the deviation θd between the read second boom target rotation angle θ2r and the current second boom target rotation angle θ2 to zero with good settling property. Is calculated.

That is, as shown in FIG. 11, it is assumed that the first boom 7 is rotated by the operator operating the operation lever 46, and the first boom rotation angle θ1 changes from θ1N to θ1M. At this time, the second boom 7 has the original rotation angle θ2N.
(Rotational angle corresponding to the first boom angle θ1N), and is kept at a deviation from the target rotation angle θ2M (the rotation angle corresponding to the first boom angle θ1M) by θd = θ2M (target rotation angle).
−θ2N (current rotation angle).

Therefore, a proportional element to this deviation θd,
Compensation by the differential element, the integral element, and the like is performed as follows.

Rd = F1 (θd) (13) Here, the function F1 is an arithmetic expression for compensating θd. When the above processing is executed by the compensation element calculation unit 53,
The second boom operation valve command calculation unit 56 corrects the calculated compensation element calculation value rd using a correction value Is corresponding to the size of the dead zone of the second boom flow control valve 35, Command I2 for the second boom flow control valve 35
Is calculated as follows.

I2 = Is + rd (14) When the command I2 is calculated by the second boom operation valve command calculating section 56, the current output section 59 outputs the command current I2.
And outputs this to the electromagnetic proportional control valve corresponding to the second boom flow control valve 35.

However, the second boom operation valve command calculation unit 56
Is monitoring the magnitude of the control deviation θd, and the range in which the control deviation θd is determined to be substantially zero (−θd1 <θd
<Θdh), the command I2 is calculated as I2 = 0 (15), the command current I2 output from the current output unit 59 is turned off (I2 = 0), and the rotation of the second boom 7 is stopped. Stop.

As a result, the current angle θ2 of the second boom 7
Always coincides with the target rotation angle θ2r (the control deviation θd becomes zero).

The compensation element calculation processing in the compensation element calculation section 53 and the command calculation processing in the second boom operation valve command calculation section 56 are performed by operating the first boom operation lever 46 by a predetermined amount from the neutral position. Executed only when V1 is input. When the operation amount signal V1 is not input (V1 = 0), the first boom 5 remains stopped. Therefore, in order to stop the rotation of the second boom 7, the compensation element calculation is performed. The compensation element calculation processing in the section 53 and the command calculation processing in the second boom operation valve command calculation section 56 are not executed. That is, the current command I2 output from the controller 50 is turned off (I2 =
0), the second boom 7 is kept stopped at the current rotation position.

As described above, by controlling the second boom 7 in accordance with the reference line S1, the working machine tip 14a
Moves along the reference line R1 shown in FIG. 7 or FIG.

By the way, the operator sometimes wants to move the work implement tip 14a along a line closer to the vehicle body 3 with respect to the reference line R1, depending on the form of work. For example, there is a case where there is an obstacle such as a wall approaching in front of the vehicle body 3 and it is desired to move the working machine tip 14a in the vertical direction just before this wall.

Under these circumstances, the operation button 46D is operated, and the work machine is pulled toward the vehicle body 3, and the work machine
Assume that 4a is positioned closer to the vehicle body 3.

Then, the judgment result of step 102 is YE
In S, even if the “automatic mode” is being executed, the “automatic control” process of step 106 is prohibited, and the procedure shifts to step 105. In step 105, the second boom 7 is rotated at a speed corresponding to the amount of pressing operation of the work button 46D. That is, the second boom 7 is manually operated independently of the operation of the first boom 5 (step 1).
05).

When the operation of the operation button 46D is completed, the determination result of step 102 is NO, and
Is YES, and the procedure moves to step 107.

In the following, the target second boom angle diagram creating section 55 for the first boom angle sets the line S corresponding to the work implement tip line R passing through the work implement tip position positioned by operating the operation button 46D as a reference. The process of creating by shifting the line S1 downward is executed (steps 107, 108, 109).

That is, as shown in FIG. 11, if the first boom rotation angle θ1 currently calculated by the first and second boom angle calculation units 51 is θ1J, the first boom angle θ1J The corresponding second boom angle θ2J is equal to the reference line S
It is read from the storage table of No. 1 and obtained (step 107).

Next, the second boom rotation angle θ2k currently calculated by the first and second boom angle calculation units 51 is obtained. As shown in FIG. 12, by operating the work button 46D,
It is assumed that the working machine tip 14a is currently located at a point K closer to the vehicle body 3 than a point J on the reference line R1 (step 108).

Next, a deviation Δθ2 between the obtained second boom angle θ2J on the reference line S1 and the current second boom angle θ2k is calculated, and this deviation Δθ2 (= θ2J−θ2k) is temporarily stored. The reference line S1 is translated downward by an amount corresponding to the deviation Δθ2, thereby creating a line S4 (step 109).

Hereinafter, in step 106, the second boom 7 is automatically controlled according to the line S4 thus created. Therefore, as shown in FIG. 12, the work implement tip 14a moves along the work implement tip line R4, which is further deviated toward the vehicle body 3 with respect to the reference line R1.

Further, during the “automatic control” in step 106, the operator operates the operation button 46D to
If the second boom rotation angle is changed from θ2P to θ2Q as shown in FIG. 1, similarly, the process of “automatic control” is temporarily inhibited, and the line S5 further shifted by the deviation θ2P−θ2Q at this time is obtained. Are created by the diagram creation unit 55 (steps 107, 108, 109). Therefore, as shown in FIG. 12, the work implement distal end 14a moves along the work implement distal end line R5 further shifted toward the vehicle body 3 with respect to the line R4.

As described above, according to the present embodiment, only by storing the reference line S1 in advance, the working machine tip line that passes through the working machine tip position positioned by manually operating the second boom 7 can be used. The line S corresponding to R can be automatically created. Of course, if the vehicle body is within the stable range, the second boom lowering operation button 46D
Operation button 46 for raising the second boom.
By operating U, it is possible to arbitrarily create the lines S4, S5, S6 deviated from the reference line S1, and move the working machine tip 14a along the respective working machine tip lines R4, R5, R6. it can.

The process of creating the lines S4, S5, S6 by shifting the reference line S1 may be performed not only during the work but also at the start of the work. This is because the work implement is stored compactly at the start of the work, and may not be in a posture suitable for the work. At the start of the operation, the operator manually operates the second boom 7 together with the first boom 5 to position the working machine tip 14a so as to have the desired working machine posture (NO in step 103). The working machine tip 14a can be moved along the lines R1, R4, R5, R6 passing through the working machine tip position (steps 107, 108, 1).
09).

However, during the execution of the “automatic control” in step 106 or at the start of the work, the operator erroneously operates the second boom raising operation button 46U.
The working machine tip 14a is indicated by a line Re virtually shown in FIG.
It may be positioned above.

Here, if the working machine tip 14a is moved along this line Re, the vehicle body may be overturned due to an increase in the overturning moment.

Therefore, as shown in FIG.
The boom raising operation button 46U is operated, and the reference line S1
When a signal indicating an angle θ2e larger than the second boom rotation angle θ2L is input, the controller 50
An alarm command signal is output to the alarm 28. As a result, the alarm 28 is actuated to alert the operator by sounding or lighting. In this case, for safety, the operation signal V3 from the second boom raising operation button 46U is used.
Is input to the controller 50, the controller 50 turns off the command current I3 to the second boom flow control valve 35 (I3 = 0).

By recognizing the alarm from the alarm 28, the operator operates the operation button 46 in a direction to stabilize the vehicle body.
U and 46D can be operated.

In FIG. 16, if "manual mode" is selected by the automatic / manual mode switch 26 (NO in step 101), step 10 is executed.
4 and the second boom 7 is rotated at a speed corresponding to the amount of pressing operation of the work buttons 46U and 46D. That is, independently of the operation of the first boom 5, the second boom 7
Is manually operated (step 104).

In this embodiment, the memory 5 shown in FIG.
8, only the reference line S1 is stored, and the other lines are obtained by correcting the reference line S1 by an amount corresponding to the shift amount. However, as shown in FIG. , S4, S5, and S6 are also stored.

For example, if the rotation angle θ2 of the second boom 7 immediately after the operation of the operation buttons 46U and 46D is θ2R, a plurality of lines S4 having the current rotation angle θ2R as a target angle on the line are provided. The line is selected from among the lines S1, S4, S5 and S6. Then, as shown in FIG. 12, the working machine tip 14a is moved along the working machine tip line R4 corresponding to the selected line S4. The same applies when other lines S1, S5 and S6 are selected.

As shown in FIG. 9, each line S1, S2, corresponding to the working machine tip line R1, R2, R3 having a different shape.
S3 may be stored in the memory 58, and a line having the current second boom rotation angle on the line may be selected from a plurality of lines S1, S2, and S3 in the same manner.

By the way, in the embodiment described above, the working machine tip 14a is connected to the line R1 (or R2, R2) in which the arc composed of the trajectory g, the trajectory e and the trajectory d is combined with a straight line.
3, R4, R5, R6), the rotation of the second boom 7 is automatically controlled so as to move along, but the tip end line of the working machine to be automatically controlled is not necessarily the arc-shaped trajectory g or d. May not be included. That is, it is only necessary to automatically control the rotation of the second boom 7 so that at least the working machine tip 14a moves along the working machine line including the linear trajectory e. For example, in FIG.
Instead of storing the reference line S1 for the entire sections θD to θC, it is also possible to store the reference line S1 only for the sections θA to θB.

Further, in the present embodiment, it is assumed that the offset boom rotation angle θ3 is a fixed angle, and the working machine tip 14a is moved to a desired working machine tip line (for example, the reference line R1) on the XY two-dimensional coordinate system. Although the control to maintain the above is performed, even if the offset boom 11 is operated during the work and the angle θ3 is changed, in response to this,
In the XYZ three-dimensional coordinate system, control may be performed to maintain the working machine tip 14a on a desired working machine tip plane (for example, a plane obtained by extending the reference line R1 in the Z-axis direction). When such control is performed, for example, FIG.
, The offset boom 11 is operated and the angle θ3
Is changed, the trajectory of the working machine tip 14a is defined by a plane (XY-Y) in which the reference line R1 (line on the XY two-dimensional coordinate system) is extended perpendicularly (in the Z-axis direction) to the paper surface. Z3
(A plane on a dimensional coordinate system).

In the present embodiment, it is assumed that the second boom 7 is automatically controlled in accordance with the operation of the first boom 5, but if the front member is a work implement, it is manually operated. The combination of the front member to be controlled and the front member to be automatically controlled in response to the manual operation can be arbitrarily set. For example, the first boom 5 may be automatically controlled according to the manual operation of the arm 12 of the excavator 1,
The second boom 7 may be automatically controlled according to a manual operation of the arm 12.

The above is the content of the “first control”.

Second control (control for limiting the maximum value of the speed of the first boom when the angular deviation of the second boom becomes large (predicted)) The first control described above is executed, and The second boom 7 is rotated following the diagram created by the diagram creating unit 55, for example, S1, and the working machine tip 14a moves along the locus R1 corresponding to the diagram S1 as shown in FIG. If it is moved with high accuracy, ideal control has been performed.

However, in practice, when the angle of the first boom 5 changes greatly due to the sudden operation of the first boom 5 by the operating lever 46, the speed of the hydraulic cylinder 8 driving the second boom 7 is increased. Is saturated, and the above diagram S
Control along 1 becomes difficult.

That is, when the angle change of the first boom 5 per unit time is small, the control deviation θd between the target rotation angle θ2r of the second boom 7 and the current rotation angle θ2 (feedback amount) is small or zero. The drive of the second boom 7 is ideally controlled following the above-mentioned diagram S1.

However, when the angle change of the first boom 5 per unit time increases, the speed of the second boom hydraulic cylinder 8 cannot follow the large angle change, and the control deviation θd increases. . For this reason, the rotation angle θ2 of the second boom 7 deviates from the diagram S1, and the work implement tip 14a deviates from the desired trajectory R1. For this reason, work may not be able to be performed accurately.

In particular, when the first boom 5 is turned downward, gravity is applied to the working machine, and
In many cases, the angular acceleration of the boom 5 increases, and the trajectory of the working machine tip 14a deviates from a desired trajectory R1.

In the second control, even if the first boom 5 is suddenly operated (especially, even if the first boom 5 is turned downward), the rotation angle θ2 of the second boom 7 is always set to the target. In order to match the rotation angle θ2r,
The trajectory a is changed to a desired trajectory R1 (or R2, R3, R3, R
(4, R5, R6) so that the work can be performed accurately.

In the excavator 1, as shown in FIG. 1, a hydraulic pump 32 is driven by an engine 31, and hydraulic oil discharged from the hydraulic pump 32 is supplied to each of the hydraulic cylinders 6, 7, and the like. Is done. When each of the hydraulic cylinders 6, 7 and the like is driven at a speed corresponding to the flow rate of the supplied pressure oil, each of the front members of the working machine, such as the first boom 5, the second boom 7, and the like, is driven. It is rotated at a rotation speed according to the speed.

Here, the rotation speed Ne (re
v / min) means that the flow rate Q (l / min) discharged from the hydraulic pump 32 is reduced. This is because the flow rate Q is expressed as Q = q · Ne, where Ne (rev / min) is the rotation speed of the engine 31 and q is the displacement volume of the hydraulic pump 32 (cc / rev). When the flow rate Q decreases, the driving speed of each of the hydraulic cylinders 6 and 8 decreases, and the rotation speed of the first boom 5 and the second boom 7 decreases.

Therefore, when the rotation speed Ne of the engine 31 decreases, the flow rate Q discharged from the hydraulic pump 32 decreases, and the flow rate Q is supplied to the hydraulic cylinder 8 for driving the second boom 7 accordingly. Flow rate is also small,
The drive speed of the hydraulic cylinder 8 is likely to be saturated.
In other words, when the engine speed Ne decreases, the speed of the second boom drive hydraulic cylinder 8 is saturated in the same manner as when the first boom operation lever 46 is rapidly operated, and the second boom is operated. 7 deviates from the diagram S1, and the working machine tip 14a deviates from the desired locus R1.

Furthermore, even when the discharge amount Q of the hydraulic pump 32 itself becomes small, the speed of the second boom driving hydraulic cylinder 8 is similarly saturated, and the second boom 7 is shifted from the above-mentioned diagram S1. The work machine tip 14a
Deviates from the desired trajectory R1.

In the second control, the engine speed Ne
Of the second boom 7 even when the discharge amount Q of the hydraulic pump 32 decreases.
2 always coincides with the target rotation angle θ2r, and the trajectory of the working machine tip 14a is changed to a desired trajectory R1 (or R2, R2).
(3, R3, R4, R5, R6) so that the work can be performed accurately.

In the second control embodiment, the deviation θd and the first boom lowering speed maximum value I1max as shown in FIG.
Is stored in the controller 50 as a storage table. Note that an arithmetic expression for obtaining I1max from θd may be stored.

Here, I1max on the vertical axis in FIG. 17 is an electromagnetic proportional control valve 39 corresponding to the first boom flow control valve.
(Boom lowering direction) indicates the upper limit value of the current command I1. That is, the current command I in the first boom lowering direction
By setting the maximum value I1max of 1, the maximum rotation speed in the first boom lowering direction can be limited.

In the correspondence shown in FIG. 17, when the deviation θd is smaller than a predetermined threshold value θda, the first boom lowering speed maximum value I1max is set to 100%. When the deviation θd is equal to or larger than the threshold value θda, the first boom lowering speed maximum value I1max is increased by 100% according to the increase of θd.
It is set to decrease gradually. Here, the threshold value θda is set in advance to a size at which it is determined that the second boom 7 cannot be controlled following the reference line S1.

Therefore, as shown in FIG. 13, the current deviation θd calculated by the difference calculator 52 between the second boom angle and the target second boom angle is input to the first boom operation valve command calculator 54. .

Then, the first boom lowering speed maximum value I1max corresponding to the current deviation θd is obtained from the correspondence shown in FIG. Then, the command I1 is set within a range not exceeding the obtained first boom lowering speed maximum value I1max.
Is generated and output to the electromagnetic proportional control valve 39 corresponding to the first boom flow control valve 34 via the current output unit 57. For this reason, the lowering rotation speed of the first boom 5 is suppressed within the range of the maximum rotation speed corresponding to the first boom lowering speed maximum value I1max.

That is, if θd is now smaller than the threshold value θda, and accordingly I1max is 100%, there is no restriction on the rotation speed in the first boom lowering direction. A command I1 corresponding to the operation amount V1 of the lever 46 is generated and directly applied as a command current I1 to the electromagnetic proportional control valve 39 (boom lowering direction) corresponding to the first boom flow control valve 34.

However, if θd is equal to or larger than the threshold value θda and I1max is smaller than 100%, the rotation speed in the first boom lowering direction is limited. That is, the command I1 corresponding to the operation amount V1 of the operation lever 46 is limited by I1max. And
The degree of the restriction increases as the deviation θd increases. For example, when I1≤I1max, I1 is directly added to the electromagnetic proportional control valve 39 (boom lowering direction) corresponding to the first boom flow control valve 34, but I1
When 1> I1max, I1max is added to the electromagnetic proportional control valve 39 (boom lowering direction) corresponding to the first boom flow control valve 34.

As described above, according to the second control, when the operation lever 46 for the first boom is suddenly operated downward and the angular deviation θd of the second boom 7 actually becomes large, Since the speed command I1 for the first boom 5 is limited, the rotation speed of the first boom 5 in the lowering direction can be suppressed, and the deviation θd can be reduced. As a result, the trajectory of the working machine tip 14a moves to the desired trajectory R1, and the work can be performed with high accuracy. In the present embodiment, the reference line R1 is assumed, but the same applies to the case where the work implement tip 14a is moved along other lines R2, R3, R3, R4, R5, and R6.

In the present embodiment, when the first boom 5 is rotated in the lowering direction, the rotation speed of the first boom in the lowering direction is limited. When the first boom is turned, the turning speed of the first boom in the raising direction may be limited.

Next, an embodiment in which the engine speed Ne is used instead of the deviation θd will be described. The setting dial for setting the target engine speed of the engine speed Ne
This embodiment is useful when a low-speed operation is performed with the rotation speed set to low.

In this embodiment, the correspondence between the engine speed Ne and the first boom lowering speed maximum value I1max as shown in FIG. 18 is stored in the controller 50 as a storage table. Note that an arithmetic expression for calculating I1max from Ne may be stored.

Here, I1max on the vertical axis in FIG. 18 is an electromagnetic proportional control valve 39 corresponding to the first boom flow control valve 34.
(Boom lowering direction) indicates the upper limit value of the current command I1. That is, the current command I in the first boom lowering direction
By setting the maximum value I1max of 1, the maximum rotation speed in the first boom lowering direction can be limited.

In the correspondence shown in FIG. 18, when the engine speed Ne is larger than a predetermined threshold value Nea, the first boom lowering speed maximum value I1max is set to 100%. When the engine speed Ne is equal to or smaller than the threshold Ne, the first boom lowering speed maximum value I1max is set to gradually increase to 100% in accordance with the increase of Ne.

Thus, as shown in FIG. 14, the current engine speed Ne detected by the engine speed sensor 27 is
Is input to the first boom operation valve command calculation unit 54.

Then, the first boom lowering speed maximum value I1max corresponding to the current engine speed Ne is calculated as shown in FIG.
8 is obtained from the correspondence shown in FIG. Then, the command I1 is generated within a range not exceeding the obtained first boom lowering speed maximum value I1max, and the first command is output via the current output unit 57.
Electromagnetic proportional control valve 39 corresponding to boom flow control valve 34
Is output to For this reason, the rotation speed of the first boom 5 is suppressed within the range of the maximum rotation speed corresponding to the first boom lowering speed maximum value I1max.

That is, if Ne is now larger than the threshold value Nea and accordingly I1max is 100%, there is no limitation on the rotation speed in the first boom lowering direction. A command I1 corresponding to the operation amount V1 of the lever 46 is generated and directly applied as a command current I1 to the electromagnetic proportional control valve 39 (boom lowering direction) corresponding to the first boom flow control valve 34.

However, when the low-speed work is being performed, Ne is equal to or smaller than the threshold value Ne.
If max is less than 100%, the first
The rotation speed in the boom lowering direction is limited, and the command I1 corresponding to the operation amount V1 of the operation lever 46 is I
Limited by 1max. And the degree of the restriction is
It increases as the rotation speed Ne decreases. For example, I1
If ≤I1max, I1 is directly added to the electromagnetic proportional control valve 39 (boom lowering direction) corresponding to the first boom flow control valve 34, but if I1> I1max, I1max is It is added to the electromagnetic proportional control valve 39 (boom lowering direction) corresponding to the flow control valve 34 for one boom.

As described above, according to the present embodiment, when low-speed work is performed, by detecting the engine speed Ne, it is predicted that the angular deviation θd of the second boom 7 will increase. Speed command I1 for first boom 5
, The rotation speed of the first boom 5 in the lowering direction can be suppressed, and thereby the deviation θd can be reduced. As a result, the trajectory of the working machine tip 14a moves to the desired trajectory R1, and the work can be performed with high accuracy. In this embodiment, the reference line R1 is assumed, but the other lines R2, R3, R3, R4, R5, R6
The same applies to the case where the work implement tip 14a is moved along.

In the embodiment shown in FIGS. 14 and 18, when the first boom 5 is rotated in the lowering direction, the rotation speed of the first boom in the lowering direction is limited. When the first boom 5 is turned in the raising direction, the first
The rotation speed of the boom in the raising direction may be limited.

In FIG. 18, the engine speed Ne on the horizontal axis may be used as the discharge amount Q of the hydraulic pump 32.

In the above-described embodiment, the maximum speed of the first boom 5 is limited by assuming a case where the second boom 7 is automatically controlled according to the operation of the first boom 5. For the front members that make up the working machine, the combination of the front members that should be manually operated and the front members that should be automatically controlled in response to this manual operation can be set arbitrarily, and the maximum speed is limited accordingly. The front member to be set can be set arbitrarily. For example, when automatically controlling the first boom 5 or the second boom 7 in response to a manual operation of the arm 12 of the excavator 1,
The maximum speed of the arm 12 may be limited.

In FIGS. 17 and 18, the correspondence is set such that I1max gradually decreases or increases at the threshold, but the value of I1max is binary before and after the threshold. It is also possible to set a correspondence that changes to.

The above is the content of the “second control”.

Third control (control for limiting the maximum value of the speed of the first boom when the load pressure of the first boom increases) In the first control described above, for example, as shown in S1 of FIG. A diagram S1 showing the correspondence between the rotation angle θ1 of the first boom 5 and the target rotation angle θ2 of the second boom 7 is set, and the first boom 5 is operated in accordance with the operation of the first boom 5 so as to follow this diagram S1. The drive control of the two booms 7 is performed.

That is, the second boom 7 is connected to the first boom 5
Is driven in accordance with the operation amount with respect to.

[0189] If the operation amount for the first boom 5 is large, the second boom 7 is rotated greatly so as to follow the diagram S1.

By the way, when a heavy load is applied to the work machine, the operator often operates the operating lever for operating the first boom 5 largely and suddenly in order to remove the load.

For example, at the work site, the first boom 5 is operated in the downward direction to bring the bucket 14 into contact with the ground,
The turning operation of turning the upper turning body 3 and changing the turning direction is performed with the footwear of the hydraulic shovel 1 being lifted off the ground contact surface.

In this case, since the working machine tip 14a is grounded and the working machine fulfills the function of "outrigger", a large load is applied to the working machine.

When the turning operation is completed, the operator operates the first boom 5 in order to remove the load on the work machine and to perform a normal excavation work or the like.
Will be operated suddenly in the upward direction.

Then, since the work implement was grounded to the ground, the load on the second boom 7 which had been stopped until then was suddenly removed. It will suddenly operate according to the operation.

This is an unexpected operation contrary to the intention of the operator, and causes a reduction in work efficiency. Also, when the second boom 7 is suddenly operated, the bucket 14
May violently slide on the ground, damaging the bucket contact surface and the bucket body. Further, in some cases, sudden operation of the second boom 7 may cause an unexpected accident.

In the third control, when a large load is applied to the work machine, even if the operator operates the front member greatly suddenly to remove the large load, the movement of the front member is not affected. The inconvenience caused by the sudden actuation of another front member driven in response to the above is eliminated.

In the third embodiment, the load P1h applied to the work machine, that is, the hydraulic cylinder 6 for driving the first boom 5, is detected by the pressure sensor 21 as load detecting means.
Is detected on the head side pressure P1h.

Therefore, according to the correspondence shown in FIG. 19, when the detected load P1h is equal to or greater than the predetermined threshold value P1ha, the maximum rotation speed of the first boom 5 in the raising direction is limited to a predetermined value or less. Is done. Hereinafter, a specific description will be given.

In the third control embodiment, the correspondence between the head side pressure P1h of the first boom hydraulic cylinder 6 and the first boom raising speed maximum value I1max as shown in FIG. It is stored as a table. Note that an arithmetic expression for calculating I1max from P1h may be stored.

Here, I1max on the vertical axis in FIG. 19 is an electromagnetic proportional control valve 38 corresponding to the first boom flow control valve 34.
The upper limit value of the current command I1 with respect to (boom raising direction) is shown. That is, the current command I in the first boom raising direction
By setting the maximum value I1max of 1, the maximum rotation speed in the first boom raising direction can be limited.

In the correspondence shown in FIG. 19, when the pressure P1h is smaller than a predetermined threshold value P1ha, the first boom raising speed maximum value I1max is set to 100%. When the pressure P1h is equal to or higher than the predetermined threshold value P1ha, the first boom raising speed maximum value I1max is set to a value smaller than 100%. Here, the threshold value P1ha
Is 100 kg / cm 2, for example, and is set in advance to the magnitude of the load at which it is determined that the first boom 5 is suddenly operated.

Therefore, as shown in FIG. 15, the head side pressure P1h of the first boom hydraulic cylinder 6 detected by the pressure sensor 21 is input to the first boom operation valve command calculation section 54.

Then, the first boom raising speed maximum value I1max corresponding to the current pressure P1h is obtained from the correspondence shown in FIG. Then, the command I1 is set within a range not exceeding the obtained first boom raising speed maximum value I1max.
Is generated and output to the electromagnetic proportional control valve 38 corresponding to the first boom flow control valve 34 via the current output unit 57. For this reason, the rotation speed in the raising direction of the first boom 5 is suppressed within the range of the maximum rotation speed corresponding to the first boom raising speed maximum value I1max.

That is, if P1h is now smaller than the threshold value P1ha, and accordingly I1max is 100%, there is no limitation on the rotation speed in the first boom raising direction. A command I1 corresponding to the operation amount V1 of the lever 46 is generated and directly applied to the electromagnetic proportional control valve 38 (boom raising direction) corresponding to the first boom flow control valve 34 as the command current I1.

However, if P1h is equal to or larger than the threshold value P1ha and I1max is accordingly smaller than 100%, the rotation speed in the first boom raising direction is limited. That is, the operation amount V1 of the operation lever 46 is
Is limited by I1max. For example, when I1 ≦ I1max, I1 is directly added to the electromagnetic proportional control valve 38 (boom raising direction) corresponding to the first boom flow control valve 34. However, when I1> I1max, I1max is added to an electromagnetic proportional control valve 38 (boom raising direction) corresponding to the first boom flow control valve 34.

As described above, according to the second control, even if the first boom operation lever 46 is greatly operated suddenly, if the load P1h applied to the work machine is large,
Since the speed command I1 for the first boom 5 is limited, the second boom 7 is suddenly operated in response to a large sudden operation of the operation lever 46 when the load applied to the working machine is suddenly removed thereafter. Will not be done.

[0207] For this reason, there is no possibility that an unexpected operation contrary to the intention of the operator occurs, so that the work efficiency is improved. In addition, the bucket 14 slides violently on the ground due to the sudden operation of the second boom 7, thereby preventing the bucket ground surface and the bucket body from being damaged. Further, an unexpected accident does not occur due to the sudden operation of the second boom 7.

In the present embodiment, the state in which the first boom 5 is operated upward to remove the load from a state in which the tip of the working machine is grounded to the ground and the working machine functions as an “outrigger” is used. Assuming below, the first boom 5 is
The maximum lifting speed of the first boom 5 is limited when it is pivoted upward, but is not limited to this, and the first boom 5 is largely suddenly operated to remove the load. In such a situation, when the first boom 5 is pivoted downward, it is also possible to limit the maximum speed below the first boom 5.

In this embodiment, the load applied to the working machine is detected by the pressure sensor provided in the hydraulic cylinder. However, if the load can be detected other than the pressure, the detection method and the type of the sensor are used. Is optional.

In this embodiment, the load applied to the work equipment is detected by the load P1h applied to the first boom 5. However, if the load applied to the work equipment can be detected, the load is limited to the first boom 5. Instead, the load on the work implement may be detected by detecting the load on another front member such as the second boom 7.

In the above-described embodiment, the maximum speed of the first boom 5 is limited by assuming that the second boom 7 is automatically controlled in accordance with the operation of the first boom 5. For the front members that make up the working machine, the combination of the front members that should be manually operated and the front members that should be automatically controlled in response to this manual operation can be set arbitrarily, and the maximum speed is limited accordingly. The front member to be set can be set arbitrarily. For example, when automatically controlling the first boom 5 or the second boom 7 in response to a manual operation of the arm 12 of the excavator 1,
The maximum speed of the arm 12 may be limited.

In FIG. 19, I1m before and after the threshold value
Although the correspondence that changes the value of ax in a binary manner is set, it is also possible to set a correspondence that gradually reduces the I1max value at the threshold.

The above is the contents of the “third control”.

Fourth Control (Control for Limiting Offset Speed According to Work Machine Height Position) In the hydraulic excavator 1 having the structure shown in FIG. 2, by operating the offset boom operation pedal 47, the control shown in FIG. As shown in b), the offset boom 11 is offset from the vehicle body 3 in the left-right direction, and the arm 12 and the bucket 14 are offset with respect to the second boom 7 to perform a trench excavation operation, a mass excavation operation and the like. I try to make it.

[0215] By the way, when performing a trench excavation work or the like, the offset boom 11 needs to be offset by a fine operation so that the bucket 14 moves left and right in the groove at a relatively low speed. By performing the offset operation with a fine operation, workability is improved.

In this case, the operator moves the bucket 14 left and right at a low speed in the groove while suppressing the speed of the offset operation by finely adjusting the operation amount of the offset pedal 47.

However, the fine operation of finely adjusting the offset pedal 47 with the foot and moving the bucket 14 left and right in the groove at a low speed requires a high level of skill.
Requires skill. This is even more so in a situation in which other operation levers such as the arm operation lever 45 in addition to the offset pedal 47 must be simultaneously operated.

For this reason, not only unskilled operators but also skilled operators have a heavy work load and large fatigue.

On the other hand, when the working machine is at a high position,
There is a demand that a fine operation is not required, but rather a quick offset operation from side to side is performed to perform excavation work at a high place.

In the fourth control, the operator can perform a fine operation in the case of performing a trench excavation work without impairing the workability when the working machine is at a high position. It is.

In the fourth control embodiment, first, the height position of the work implement, specifically, the height H of the arm top 12a is detected. The arm top height H is obtained by calculating the coordinate position (X5, Y5, Z5) of the armtop 12a from the above (1) to (11), and adding the known length from the ground surface GL to the boom foot 5a to the obtained Y5. By adding
Is obtained.

Then, as shown in FIG. 20, when the detected height position H of the work implement is equal to or less than a predetermined threshold value Ha, the offset maximum operation speed of the offset boom 11 is limited. Hereinafter, a specific description will be given.

In the fourth embodiment, the arm top height H and the offset boom 11 as shown in FIG.
The corresponding relationship with the maximum offset speed ve3 (Q3) is stored in the controller 50 as a storage table. Note that an arithmetic expression for obtaining ve3 (Q3) from H may be stored.

Here, ve3 on the vertical axis in FIG. 20 is the rotation speed of the offset boom 11, which is proportional to the flow rate Q3 supplied from the offset boom flow control valve 36 to the offset boom hydraulic cylinder 10. Is proportional to the current command I3 for the offset boom flow control valve 36.

In the correspondence shown in FIG. 19, when the arm top height H is larger than a predetermined threshold value Ha (for example, set to 1 m), the offset speed maximum value ve3
(Q3) is set to 100%. When the arm top height H is equal to or less than the predetermined threshold value Ha, the offset speed maximum value ve3 (Q3) is gradually reduced, and is set to 70% when the arm top height H is equal to or less than the ground surface GL. Here, the threshold value Ha is less than the height of the offset boom 11.
Is set in advance to a size determined to be finely operated.

On the other hand, as shown in FIGS. 21 (a) and 21 (b), the correspondence between the operation amount St of the offset pedal 47 and the offset operation speed (flow rate command) Q3P of the offset boom 11 is set.

That is, the operation stroke St of the offset pedal 47 is proportional to the offset voltage V3 which is an electric signal indicating the operation stroke (FIG. 21).
(A)) The offset voltage V3 is proportional to the offset operation speed (flow rate command) Q3P (FIG. 21).
(B)).

Therefore, the current arm top height H is calculated, and the corresponding maximum offset speed Q3 of the offset boom 11 is obtained from the correspondence shown in FIG.

On the other hand, when the operator
Is operated, the operation amount V3 is input to the controller 50, and the speed Q3P of the offset boom 11 corresponding to the current operation amount V1 is obtained from the correspondence shown in FIG.

Then, the speed Q0 of the smaller offset boom 11 is selected from the obtained speeds Q3 and Q3P of the offset boom 11.

In accordance with the proportional relationship shown in FIG. 22A, a current command I3 proportional to the speed Q0 of the selected offset boom 11 is generated and applied to the offset boom flow control valve 36. As a result,
According to the proportional relationship shown in FIG. 22B, the offset boom 11 is rotated right and left at a speed ve3 proportional to the current command I3.

FIG. 23 shows the operation stroke amount St of the offset pedal 47 and the rotation speed ve3 of the offset boom 11.
Are shown.

Now, the arm top height H is equal to the threshold value Ha.
Suppose that

Then, as shown in FIG. 23, the operation stroke amount St of the offset pedal 47 becomes smaller in the fine operation region (〜St).
In the case of (1), the speed of the offset boom 11 increases in proportion to the amount of depression of the pedal. Eventually, when the operation stroke amount St of the offset pedal 47 reaches the full operation area (St1 to St2), even if the pedal is depressed, the speed of the offset boom 11 remains at the constant value veD and does not increase further. This constant value veD is set to a smaller value as the arm top height H is lower. For example, H
However, below ground surface GL, veD is set to 70%.

For this reason, when the arm top 12a is at a low position and digging a trench is performed, the operating speed ve3 of the offset boom 11 is low regardless of the operation stroke amount St of the offset pedal 47. (Speed veD or less).

Now, the arm top height H is equal to the threshold value Ha.
It is assumed that the value is larger than.

Then, as shown in FIG. 23, the operation stroke amount St of the offset pedal 47 becomes smaller in the fine operation region (〜St).
In the case of (1), the speed of the offset boom 11 increases in proportion to the amount of depression of the pedal. Eventually, even when the operation stroke amount St of the offset pedal 47 reaches the full operation area (St1 to St2), the speed of the offset boom 11 increases in proportion to the pedal depression amount, and reaches the maximum speed veU.

Therefore, when the arm top 12a is at a high position and excavation work at a high place or the like is performed, the speed ve3 according to the operation stroke amount St of the offset pedal 47 is used.
, The offset boom 11 is operated at high speed.

Therefore, when the work machine is at a low position as an operator and a side ditch digging operation or the like is performed, the operation of finely operating the offset pedal 47 is released, and the work load and fatigue are reduced. On the other hand, when the work implement is at a high position and performs excavation work at a high place, the operation speed of the offset boom 11 is not limited to a low speed, so that work efficiency can be improved.

In this embodiment, the arm top 12
The height H of the working machine is detected to detect the height of the working machine. However, the present invention is not limited to this. Any location indicating the height of the working machine, such as the bucket blade position 14a, is used. The position at which the height is to be detected can be set arbitrarily.

[0241] The means for operating the offset boom 11 is assumed to be a pedal, but any operating means such as an operating lever and an operating switch can be used.

In FIG. 20, the correspondence is set such that the offset speed is gradually changed at the threshold, but the value of the offset speed is changed binary before and after the threshold. It is also possible to set such correspondence.

In the present embodiment, it is assumed that the offset voltage V3 is output in proportion to the amount of depression of the offset pedal 47 (FIG. 21 (a)). The present invention is also applicable to a case where the offset voltage V3 is changed in a binary manner. The relationship between the pedal stroke St (on / off signal) and the offset speed ve3 in this case is represented by a two-dot chain line in FIG.

When the pedal is off (~ St1), the speed of the offset boom 11 becomes zero. When the pedal is turned on (St1 to St2), the arm top position 12a is at a low position (H is 1 m above the ground surface GL).
(Below), when the side ditch work is being performed, the operation speed v e3 of the offset boom 11 is lower than the lower speed v
eD. When the pedal is on (St1 to St2)
When the arm top 12a is located at a high position (H is 1 m or more above the ground surface GL) and excavation work is performed at a high place, the operation speed ve3 of the offset boom 11 becomes a high speed veU.

The above is the contents of the fourth control.

Fifth control (control for restricting the rotation speed of the second boom according to the height position of the work implement) In the hydraulic excavator 1 having the structure shown in FIG. 2, the second boom operation buttons 46U and 46D By operating, the second boom 7 is rotated to perform a trench excavation operation, a mass excavation operation, and the like.

By the way, when performing a trench excavation work or the like, it is necessary to finely operate the second boom 7 so that the bucket 14 moves at a relatively low speed in the trench. Workability is improved by performing the operation of the second boom 7 by a fine operation.

Therefore, conventionally, as an operator, by finely adjusting the operation of the second boom operation buttons 46U and 46D, the operator can lower the bucket 14 in the groove while suppressing the operation speed of the second boom 7. It was moving at speed.

However, the second boom operation buttons 46U, 46
The fine operation of finely adjusting the operation of D and moving the bucket 14 at a low speed in the groove requires a high level of skill and skill. Moreover, the second boom operation button 46
Under the situation where other operation levers such as bucket operation levers other than U and 46D must be simultaneously operated simultaneously,
Even more so.

For this reason, not only unskilled operators but also skilled operators have a heavy work load and heavy fatigue.

On the other hand, when the working machine is at a high position,
There is a demand that the second boom 7 be operated promptly in order to efficiently perform the excavation work at a high altitude without requiring fine operation.

In the fifth control, the operator can perform fine operation work such as digging work without burdening the operator without impairing the workability when the work machine is at a high position. It is.

In the fifth control embodiment, first, the height position of the working machine is detected. Specifically, the rotation angle θ1 of the first boom is detected by the rotation angle detection sensor 17 as a value indicating the height position of the work implement.

Then, as shown in FIG. 24, when the detected first boom rotation angle θ1 is equal to or smaller than a predetermined threshold θ1a, the maximum speed value of the second boom 7 is limited. Less than,
This will be specifically described.

In the fifth embodiment, the correspondence between the first boom rotation angle θ1 and the maximum speed ve2 (Q2) of the second boom 7 as shown in FIG. 24 is stored in the controller 50 as a storage table. Have been done. Note that an arithmetic expression for obtaining ve2 (Q2) from θ1 may be stored.

Here, ve2 on the vertical axis in FIG. 24 is the rotation speed of the second boom 7, which is the flow rate Q2 supplied from the second boom flow control valve 35 to the second boom hydraulic cylinder 8. , And is proportional to the current command I2 for the second boom flow control valve 35.

In the correspondence shown in FIG. 24, when the first boom rotation angle θ1 is larger than a predetermined threshold value θ1a (for example, set to 40 °), the second boom speed maximum value ve2 (Q2) Is set to 100%. When the first boom rotation angle θ1 is equal to or less than a predetermined threshold value θ1a, the second boom speed maximum value ve2 (Q2) gradually decreases and reaches 60% at a predetermined angle θ1b (for example, 10 °). Is set to maintain 60%. here,
The threshold value θ1a is set in advance to a size at which it is determined that the second boom 7 is finely operated below the angle.

On the other hand, as shown in FIGS. 25A and 25B, the second boom operation buttons (switches) 46U,
The correspondence between the operation speed (flow rate command) Q2P of the second boom 7 and the 6D operation amount St is set.

That is, the operation amount St of the operation buttons 46U and 46D is proportional to the second boom voltage V2 which is an electric signal indicating the operation amount (FIG. 25 (a)). , 2nd boom operation speed (flow command) Q2P
Is in a proportional relationship (FIG. 25B).

Then, the current first boom rotation angle θ1 is detected, and the speed maximum value Q2 of the second boom 7 corresponding thereto is detected.
Are obtained from the correspondence shown in FIG.

On the other hand, the operator operates the operation buttons 46U and 46D.
Is operated, the operation amount V2 is input to the controller 50, and the second boom 7 corresponding to the current operation amount V2 is operated.
Is obtained from the correspondence shown in FIG. 25 (b).

Then, the speed QB of the second boom 7 which is smaller among the obtained speeds Q2 and Q2P of the second boom 7 is selected.

Then, in accordance with the proportional relationship shown in FIG. 26A, a current command I2 proportional to the selected speed QB of the second boom 7 is generated, and this is added to the second boom flow control valve 35. Can be As a result, the second boom 7 is rotated at a speed ve2 proportional to the current command I2 according to the proportional relationship shown in FIG.

FIG. 27 shows the correspondence between the operation amounts St of the second boom operation buttons (switches) 46U and 46D and the rotation speed ve2 of the second boom 7.

Now, the first boom rotation angle θ1 is equal to the threshold θ1
a

Then, as shown in FIG.
When the operation amount St of U, 46D is in the fine operation area (〜St1), the speed of the second boom 7 increases in proportion to the operation amount of the operation button. Eventually, when the operation amount St of the operation buttons 46U and 46D reaches the full operation area (St1 to St2), even if the operation button is pressed, the speed of the second boom 7 is kept at a constant value veD.
And will not rise any further. This constant value veD has a lower value as the first boom rotation angle θ1 is smaller. When θ1 is equal to or smaller than θ1b, veD is 60%.

For this reason, when the first boom rotation angle θ1 is small and the digging work is performed, the operation button 46
Regardless of the operation amount St of the U and 46D, the operation speed ve2 of the second boom 7 can be kept low (the speed veD or less).

Now, the first boom rotation angle θ1 is equal to the threshold θ1
Assume that the value is larger than a.

Then, as shown in FIG.
When the operation amount St of U, 46D is in the fine operation area (〜St1), the speed of the second boom 7 increases in proportion to the operation amount of the operation button. Eventually, even if the operation amount St of the operation buttons 46U and 46D reaches the full operation area (St1 to St2), the speed of the second boom 7 increases in proportion to the operation amount of the operation buttons, and the maximum speed veU Reach

Thus, the first boom rotation angle θ1 is large,
When performing high-altitude excavation work, the operation button 46U,
The second boom 7 is operated at a high speed at a speed ve2 corresponding to the operation amount St of 46D.

As a result, when the work machine is in a low position as an operator and a side digging operation or the like is performed, the operation button 46 is used.
The work of finely operating the U and 46D is released, and the work load and fatigue are reduced. On the other hand, when the work implement is at a high position and performs excavation work at a high place, the operation speed of the second boom 7 is not limited to a low speed, so that work efficiency can be improved.

In the present embodiment, the height of the work implement is detected by detecting the first boom rotation angle θ1, but the present invention is not limited to this.
Height H, the height of the first boom 5 or the second boom 7, etc.
As long as the value indicates the height of the working machine, a height other than the angle may be used, and a portion where the height is to be detected can be set arbitrarily.

The means for operating the second boom 7 is controlled by an electric signal V input to the controller 50 in accordance with the operation amount.
Although buttons 46U and 46D in which 2 changes proportionally are assumed, any operation means such as an operation lever, an operation pedal, and an operation switch can be used.

In FIG. 24, the correspondence is set such that the second boom speed is gradually changed on the basis of the threshold value. It is also possible to set a correspondence relationship that changes dynamically.

In this embodiment, the operation buttons 46U, 4U
It is assumed that the second boom voltage V2 is output in proportion to the 6D operation amount (FIG. 25 (a)). However, the case where the offset voltage V2 is changed in a binary manner by turning on and off the switch is also assumed. Applicable. In this case, the relationship between the operation amount (on / off signal) St of the second boom operation switch St and the second boom speed ve2 is represented by a two-dot chain line in FIG.

When the second boom operation switch is turned off (to St1), the speed of the second boom 7 becomes zero. When the second boom operation switch is turned on (St1 to St2), the first boom angle is a small angle (θ1 is smaller than 40 °), and the side ditch digging operation is performed. , The operating speed ve2 of the second boom 7 becomes a low speed veD. When the second boom operation switch is turned on (St1 to St2) and the first boom angle is a large angle (θ1 is 40 ° or more) and high-altitude excavation work or the like is performed, Operating speed ve2 of the second boom 7
Becomes a high speed v eU.

The above is the contents of the fifth control.

The fifth control may be combined with the first control, the second control, the third control, and the fourth control, or may be performed independently.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of a control device for a construction machine according to the present invention.

FIG. 2A is a side view of a hydraulic shovel provided with an offset boom, and FIG. 2B is an A view of FIG. 2A.

3 is a diagram showing a geometric relationship of a working machine of the hydraulic shovel shown in FIG. 2, FIG. 3 (b) is a side view, and FIG. 3 (a).
Is a top view.

FIG. 4 is a table showing a coordinate position of each point of the working machine of the hydraulic shovel shown in FIG. 3 and a functional expression of an arm-to-ground angle.

FIG. 5 is a side view of a hydraulic excavator provided with two booms.

6 (a) is a diagram showing an arrangement of left and right levers, and FIG. 6 (b) is a perspective view showing an upper portion of a left lever shown in FIG. 6 (a).

FIG. 7 is a side view showing a locus drawn by the tip of the working machine of the hydraulic shovel.

FIG. 8 is a side view showing a locus drawn by the tip of the work machine at the work site by the hydraulic shovel.

FIG. 9 is a diagram showing a correspondence relationship between a first boom angle and a second boom target angle stored in the controller shown in FIG. 1;

FIG. 10 is a diagram showing another correspondence between the first boom angle and the second boom target angle stored in the controller shown in FIG. 1;

FIG. 11 is a diagram showing still another correspondence between the first boom angle and the second boom target angle stored in the controller shown in FIG. 1;

FIG. 12 is a side view illustrating a trajectory drawn by the tip of the work machine;

FIG. 13 is a diagram exemplifying a functional block diagram of a controller shown in FIG. 1;

FIG. 14 is a diagram illustrating a functional block diagram of a controller shown in FIG. 1;

FIG. 15 is a diagram exemplifying a functional block diagram of a controller shown in FIG. 1;

FIG. 16 is a flowchart illustrating a procedure of processing executed by the controller shown in FIG. 1;

FIG. 17 is a graph showing the correspondence between the deviation between the target angle of the second boom and the current angle and the maximum value of the speed in the lowering direction of the first boom.

FIG. 18 is a graph showing the correspondence between the engine speed and the maximum value of the speed in the lowering direction of the first boom.

FIG. 19 is a graph showing the correspondence between the head side pressure of the first boom cylinder and the maximum value of the speed of the first boom in the lowering direction.

FIG. 20 is a graph showing a correspondence between an arm top height and an offset boom speed (flow rate command).

FIG. 21A is a graph showing a correspondence relationship between a stroke of an offset boom pedal and an offset voltage corresponding to an operation amount of the offset pedal;
(B) is a graph showing the correspondence between the offset voltage and the flow rate command for the offset boom.

FIG. 22 (a) is a graph showing a correspondence relationship between a flow command for the offset boom and a current command for the offset boom flow control valve, and FIG. 22 (b) is a graph showing the current for the offset boom flow control valve. It is a graph which shows the correspondence of a command and the drive speed of an offset boom.

FIG. 23 is a graph showing the correspondence between the stroke of the offset boom pedal and the drive speed of the offset boom in the embodiment.

FIG. 24 is a graph showing the correspondence between the angle of the first boom and the speed (flow rate command) of the second boom.

FIG. 25A is a graph showing the correspondence between the operation amount of the second boom switch and the second boom voltage corresponding to the operation amount of the second boom switch;
(B) is a graph showing the correspondence between the second boom voltage and the flow rate command for the second boom.

26 (a) is a graph showing a correspondence between a flow command for the second boom and a current command for the flow control valve for the second boom, and FIG. 26 (b) is a flow control for the second boom. It is a graph which shows the correspondence of the current command with respect to a valve, and the drive speed of a 2nd boom.

FIG. 27 is a graph showing the correspondence between the operation amount of the second boom switch and the driving speed of the second boom in the embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Hydraulic excavator 3 Body (upper revolving superstructure) 5, 5A First boom 6, 6A First boom hydraulic cylinder 7, 7A Second boom 7B Work implement link 8, 8A Second boom hydraulic cylinder 9, 9A Bracket 10 Offset Hydraulic cylinder for offset 11 Offset boom 12, 12A arm 12a Arm top position 13, 13A Hydraulic cylinder for arm 12a Arm top position 14 Bucket 14a Bucket tip position (work implement tip position) 17 First boom angle sensor 18 Second boom angle sensor 16 Offset angle sensor 19 Arm angle sensor 21 Hydraulic cylinder head pressure sensor for first boom 22 Hydraulic cylinder bottom pressure sensor for first boom 23 Hydraulic cylinder head pressure sensor for second boom 24 Hydraulic cylinder bottom pressure sensor for second boom 25 Operation panel ( Monitor) 26 Automatic / Manual mode switch 27 Engine speed sensor 28 Alarm 31 Engine 32 Hydraulic pump 33 Pilot pump 34 First boom flow control valve 35 Second boom flow control valve 36 Offset boom flow control valve 37 Arm Flow control valve 45 left operation lever 46 right operation lever 46U, 46D second boom manual operation switch 47 offset pedal operation pedal 50 controller 51 first and second boom angle calculation unit 52 first boom angle and target second Boom angle difference calculation unit 53 Compensation element calculation unit 54 First boom operation valve command calculation unit 55 Target second boom angle diagram creation unit for first boom angle 56 Second boom control valve command calculation unit 57, 59 Current output unit 58 Target Second Boom Angle Reference Diagram Memory for First Boom Angle

Claims (3)

[Claims] A first front member disposed in front of the vehicle body so as to be rotatable in a vertical direction; and a second front member connected to the first front member so as to be rotatable in a vertical direction. A work machine control device for a construction machine, comprising: a work machine having at least a height of the work machine, wherein the work machine control device controls a rotation speed of the second front member according to an operation amount of an operation means. The height position of the work implement detected by the height position detection means is equal to or less than a predetermined height position, the maximum rotation speed of the second front member to a predetermined value or less A work machine control device for a construction machine, comprising a control means for limiting. 2. A first front member disposed in front of a vehicle body so as to be rotatable in a vertical direction, and a second front member connected to the first front member so as to be rotatable in a vertical direction. A work machine control device for a construction machine, comprising: a work machine having at least a height of the work machine, wherein the work machine control device controls a rotation speed of the second front member according to an operation amount of an operation means. Position detecting means, the maximum rotation speed of the second front member when the height position of the work implement is equal to or less than a predetermined height position, the height position of the work implement is the predetermined height A setting for setting a correspondence relationship between the height position of the work implement and the maximum rotation speed of the second front member so as to be smaller than the maximum rotation speed of the second front member when the position is larger than the position. Means, the height position A maximum rotation speed of the second front member corresponding to the height position of the work implement detected by the detection means is obtained from the content set by the setting means, and is within a range not more than the obtained maximum rotation speed. And a control means for controlling a rotation speed of the second front member. 3. A first front member disposed in front of the vehicle body so as to be rotatable in the vertical direction, and a second front member connected to the first front member so as to be rotatable in the vertical direction. A work machine control device for a construction machine, comprising: a work machine having at least a height of the work machine, wherein the work machine control device controls a rotation speed of the second front member according to an operation amount of an operation means. Position detection means, operation amount detection means for detecting the operation amount of the operation means, maximum rotation speed of the second front member when the height position of the work implement is equal to or less than a predetermined height position However, the second position with respect to the height position of the work implement is smaller than the maximum rotation speed of the second front member when the height position of the work implement is larger than the predetermined height position. Maximum rotation of front member First setting means for setting a first correspondence between speeds; second setting means for setting a second correspondence between a rotation speed of the second front member and an operation amount of the operation means; The maximum rotation speed of the second front member corresponding to the current height position of the working machine detected by the height position detection means is obtained from the first correspondence, and the operation amount detection means The rotation speed of the second front member corresponding to the detected current operation amount of the operation means is obtained from the second correspondence relationship, and the smaller rotation speed among the obtained rotation speeds is obtained. A work machine control device for a construction machine, comprising: a control unit configured to control a rotation speed of the second front member.