JPS5839978B2 - Your Tsushiyo Bernadono Senkaiki Sekisei Giyohouhou Oyobi Souchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method and apparatus for controlling the swing trajectory of a hydraulic excavator or the like when loading excavated soil into a dump truck or the like in a construction machine having a rotating body such as a hydraulic excavator or a loader excavator. It is related to.

Conventionally, when loading earth and sand excavated by a hydraulic excavator or the like into a dump truck, the operator had to use a combination of four operating levers installed in the driver's seat: boom, arm, packet, and rotation levers. , the work was extremely complex and required skill.

As a result, not only does the operator become extremely fatigued and work efficiency decreases, but when operated by an inexperienced operator, the front of the hydraulic excavator may hit the dump truck, causing damage to the machine.

The present invention was made in view of the above-mentioned conventional drawbacks, and is used in hydraulic excavators and the like that control the packet swing locus by appropriately combining the displacements of the boom cylinder, arm cylinder, and packet cylinder and the rotational angle displacement of the swing motor, after the completion of excavation. First, select whether the rotating body turns to the left or right and instruct the center of rotation of the packet or the moving direction of the packet cutting edge on a preset linear trajectory, then operate the turning lever to rotate the rotating body and the traveling body. The boom and arm, or each displacement of the boom, arm and packet, in which the center of rotation of the packet or the packet cutting edge should move on a linear trajectory set in advance according to this relative displacement angle from the position immediately after excavation. is calculated by a model calculation mechanism, and a state in which the packet rotation center or the packet cutting edge moves on the trajectory in proportion to the relative displacement angle by the output from the packet calculation mechanism, and a state in which the rotating body turns independently. We provide a method for controlling the turning trajectory of a hydraulic excavator that controls the turning trajectory of packets by selectively instructing, and a device that embodies this method. The purpose of this system is to easily and safely control the turning trajectory of hydraulic excavators, etc.

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

FIG. 1 is a diagram showing a state in which earth and sand excavated by a hydraulic excavator is being loaded into a dump truck. In the figure, 1 is the main body of the hydraulic excavator, which is composed of a revolving body 1a and a traveling body 1b.

2 is a boom whose base end is pivoted to the revolving structure 1a, 3 is an arm that is pivoted to the tip of the boom 2, 4 is a packet that is pivoted to the tip of the arm, and ? Artificial excavator - Front attachment is boom 2. The arm 3 and bucket 4 form a link mechanism.

5 is a boom drive cylinder, 6 is an arm drive cylinder, and 7 is a packet drive cylinder.

In the figure, the dashed line indicates the attitude of the front attachment immediately after excavation, and the solid line indicates the predetermined position from within the plane indicated by the broken line to the position where the rotating body 1a is loaded into the dump trunk 8 relative to the traveling body 1b. This is the posture of the front attachment in a plane rotated by an angle of .

As shown in the figure, while the revolving structure 1a rotates from the position immediately after excavation to the position where dump truck 8 is loaded, the attitude of the front attachment must change from the state shown by the broken line to the state shown by the solid line.

In the figure, the pivot point of the base end of the boom is Pl, the pivot point between the tip of the boom 2 and the arm 3 is P2, the center of rotation of the packet 4 at the tip of the arm 3 is P3, and the packet cutting edge is T.

At this time, G of the rotation center point P2 of the packet 4 immediately after excavation.

The height from L (this is the AA line) is H8, the distance from the turning center CC line is Ro, the height from G is just before being released to the dump truck 8, the height from L is Hl, the distance from the turning center CC line is Let the distance be R1.

In addition, the line connecting the position of P3 immediately after excavation and the position of P3 just before being released to the dump truck 8 is the LL line, and similarly, the line connecting the respective positions of the packet cutting edge T immediately after excavation and just before being released is the XX line. do.

Further, the angle β indicates the angle between the line connecting the 43 points and T and the XX line.

This shows an example of a model link calculation mechanism similar to the front attachment of a hydraulic excavator, etc., which is installed to automatically operate the second turning operation.
0 corresponds to boom 2 in Figure 1, and link 11 corresponds to arm 3.
, and each point P 1' y P 2' + P 3' corresponds to Pl, P2 . This corresponds to each point of P3.

Further, 9 is a slider pivotally attached to the tip 237 points of the link 11, and the slider 9 is a model link along a locus L/L/ line similar to the locus LL line in which the 43 points should move in Fig. 1. It is constrained to pivot in a groove in a guide member 12 provided on the mechanism.

Therefore, the tip P3/point of link 11 is always L/L/
Move on the line.

13a and 13b are limit switches that can be fixed at any position on the guide member 12;
A serves to turn off the automatic operation when the link 11 is raised, and a limit switch 13b serves to turn off the automatic operation when the link 11 is lowered.

The amount of movement of the 43 points on the guide member 12 is configured to move in proportion to the amount of operation of a turning lever provided in the driver's cab of the rotating structure 1a, that is, the turning angle of the rotating structure 1a.

3 and 4 show an embodiment of a mechanism for moving 231 points along the guide member 12 in proportion to the turning angle. In the figures, the same reference numerals as in FIG. 2 indicate the same parts. or indicate the equivalent part.

In this embodiment, the slider 9 is a nut screwed onto a ball screw 15 arranged in parallel with the guide member 12.

The ball screw 15 is connected to a servo motor 17 via a reducer 16.
Driven by.

When the ball screw 15 is driven, the slider 9 moves along the guide member 12, so P3' is the trajectory L'L'
It will move on the line.

In FIG. 3, 18 is a detector that detects a relative elevation angle of 0 between the rotating body 1a and the traveling body 1b and generates an electric signal, and 19 is a detector that determines whether or not the operator instructs automatic control or the limit switches 13a, 13b. The switch circuit 20 turns the circuit ON and OFF depending on whether it works or not, and the switch circuit 20 is switched depending on whether to release earth after turning left or after turning right.
A changeover switch 21 is a servo amplifier that keeps the direction of movement on the guide member 12 constant at a point corresponding to the packet rotation center point in FIG. 2 during this free turning.

The servo motor 17 is driven by the output sent through the detector 18, the switch circuit 19, the changeover switch 20, and the servo amplifier 21 in proportion to the change in the relative displacement angle 0 only when the switch circuit 19 is ON.

This proportionality constant takes the maximum constant value within the range allowed by the pump capacity and hydraulic circuit configuration.

As mentioned above, FIG. 5 shows that the 237 points at the tip of the link 11 are at
An embodiment of the servo mechanism of the present invention controls the packet rotation center point P3 of a hydraulic excavator to move on the LL line using a master-slave method using a model link calculation mechanism configured to move on the LL line. This is what is shown.

In the figures, the same reference numerals as in FIGS. 1 and 2 indicate the same or corresponding parts.

30 indicates the model link calculation mechanism shown in FIG. 2, and 22
23 is a directional control valve for operating the packet cylinder, 23 is a servo valve for operating the boom cylinder, and 24 is a servo valve for operating the arm cylinder.

At each fulcrum P, , P, between the links that make up the hydraulic excavator front attachment, and at each fulcrum P1'+P2' of the model link calculation mechanism, there is a system for detecting the relative displacement angle between each element forming each link mechanism. For example, a detector such as a synchro or potentiometer is provided, α1 is the boom angle detected at 21 points, and α2 is the boom angle detected at 4 points.
The arm angle α1' is the angle of the link 10 detected at 217 points, and α2' is the angle of the link 11 detected at 227 points.

25a is a servo arp that compares the boom angle α1 and the angle α1' of the link 10 and outputs an output in proportion to the difference, and operates the servo valve 23; 25b is the arm angle α2 and the link 1;
This is a servo amplifier that compares the angle α2' of 1 and outputs an output proportional to the difference to operate the servo valve 24.

Reference numeral 26 indicates a changeover switch for switching the turning trajectory control to automatic or manual mode, and reference numerals 27a and 27b indicate manual operation levers that emit electric signals to operate the servo valves 23 and 24, respectively.

The manual operation levers 27a, 27b are connected to each servo amplifier 25a, 25b via a changeover switch 26, respectively, and generate an electric signal proportional to the operation stroke of each lever to transmit an electric signal to each servo valve 23 via the servo amplifiers 25a, 25b. 24.

The present invention will be described in detail below with respect to the embodiments shown in FIGS. 2 to 5.

Earth and sand is excavated by a hydraulic excavator, and in the posture immediately after excavation, the operator first sets the changeover switch 26 to the automatic position and operates the swing lever to align the swing structure 1a with the position of the dump truck 8 and swing it to the left or right. let

At this time, the detector 18 detects a relative displacement angle of 0 between the rotating body 1a and the traveling body 1b, and issues an electric signal to the switch circuit 1.
9. The servo motor 17 is rotated through the changeover switch 20 and the servo amplifier 21 in proportion to the change in relative displacement angle, the ball screw 15 is rotated, and the slider 9 is moved to the guide member 12 on the model link calculation mechanism. Start moving the upper part upward from the position indicated by the broken line in FIG.

Therefore, 231 points will rise on the L/L/ line.

Further, the changeover switch 20 is set in advance so that the servo motor 17 rotates in a direction in which the slider 9 moves upward in accordance with the turning direction.

As the slider 9 moves, the links 10 and 11 are also displaced, and the detectors provided at the fulcrums P1' and P2' detect the respective link angles α1' and α2' and send electrical signals to the servo amplifiers 25a and 25b. send to

Further, detectors provided at each of the fulcrums P1 and P2 at the front of the hydraulic excavator detect the boom angle α1 and the arm angle α2 and send electrical signals to the servo amplifiers 25a and 25b.

The servo amplifiers 25a and 25b are α1, α1' and α2.
and α2' are compared, and an output is generated based on the difference, and the servo valves 23 and 24 are operated.

Therefore, the boom cylinder 5 and the arm cylinder 6 are actuated, and the boom 2 and the arm 3 are
and α2 and α2 are respectively displaced to be equal.

Therefore, the packet rotation center point P3 moves on the trajectory LL line in proportion to the change in the relative displacement angle 0.

As the relative displacement angle changes, the slider 9 moves upward from the position indicated by the broken line in FIG. 2 to the position indicated by the solid line in FIG. 2, as described above.

At this time, the packet rotation center point P3 moves on the locus LL line and assumes a posture on the verge of release.

However, at this point, the revolving structure 1a has not yet been turned to the position where it is loaded onto the dump truck 8.

If you now change the switch from the automatic position to the manual position,
While maintaining the packet rotation center point P3 in a posture on the verge of release, the rotating body 1a is rotated to a position where it is loaded onto the dump truck 8, and at this position, the rotating lever is returned to the neutral position to stop the rotating operation.

Here, after manipulating the packet 4 to release earth and sand onto the dump truck 8, the turning control lever was operated in the opposite direction to turn the revolving structure 1a at a certain angle to prevent the bucket 4 from hitting the dump truck 8. When the rear switch 26 is set to the automatic position, the 231st point changes to L in proportion to the change in relative displacement angle 0.
/ L/ descends on the line, link 10 and link 11
is displaced.

As mentioned above, boom 2 and arm 3 have a boom angle α1
The arm angle α2 and the arm angle α2 are controlled to be equal to the link angle α1′ and the link angle α2′, respectively, and the packet rotation center point P3 descends on the LL line in proportion to the change in the relative displacement angle 0.

At this time, the packet rotation center point P3 reaches the excavation attitude before the rotating body 1a returns to the original excavation point.

At this time, when the switch 26 is returned from automatic to manual, the packet rotation center point P3 remains in the digging position, the swing body 1a swings to the digging position, and at this position the swing lever is returned to the neutral position to stop the swing operation. .

Therefore, the next digging operation can begin.

In the above action, the packet rotation center point P3 is the locus L
If the switch 26 is not set to the manual position when it ascends or descends on the L line and reaches the position just before release or the position immediately before excavation, P3 will continue to advance along the trajectory LL line.

Therefore, the limit switches 13a and 13b are provided to prevent this.

Alternatively, when the packet rotation center point P3 reaches the release position or excavation position, the limit switches 13a, 13
If b is set to work, even if the switch 26 is left in the automatic position, the 23-point trajectory LL will be automatically set.
The range of movement on the line will be determined.

In the above explanation, there is a proportional relationship between the change in the relative displacement angle 0 between the rotating body 1a and the traveling body 1b and the amount of movement of the link tip point P3'(7), that is, the amount of movement of the packet rotation center point P3. The most general embodiment of the present invention has been described in which the constant is set to the maximum constant value within the range allowed by the pump capacity and hydraulic circuit configuration of the hydraulic excavator.

In actual work, the rotation angle of the rotating body 1a from the excavation position to the release position changes arbitrarily for a fixed amount of movement of the packet rotation center point P3, and FIG. In the embodiment of the present invention in which the angle of rotation is set to a constant value, the above-mentioned turning angle can be changed to an arbitrary value by appropriately switching the switch 26 between the self-d device (this is referred to as automatic ON) and the manual upright position (this is referred to as automatic OFF). This shows that it is possible to control the

In the figure, the height H from the 23 points G and L and the distance R from the 23 point turning center line CC are taken on the vertical axis, and the relative displacement angle 0 is taken on the horizontal axis.

Further, θ indicates the amount of change in the relative displacement angle ■ when the changeover switch 26 is automatically turned on.

As shown in the figure, when the turning lever is operated and the switch 26 is turned on and off as appropriate, the change in the automatic ON state of H and R is the change in relative displacement angle θ1θ2
．． θ3. It changes in proportion to θ4, and HLR changes from Ho to R6 to R1.

Further, in the automatic OFF state, the relative displacement angle 0 (turning angle) changes, but H and R do not change.

Therefore, the total sum of changes in relative displacement angle 0 in the automatic ON state where 23 points move within a certain range θT = θ1 + θ2+
Even if θ3+θ4 is always constant, the turning angle can be changed arbitrarily.

FIG. 6 shows turning trajectory control in which the proportionality constant can be arbitrarily adjusted by an external command.

As shown in the figure, by adjusting the proportionality constant from the outside as appropriate, the relative displacement angle 0 (turning angle) is set to 01 as shown in the figure while H is displaced from H8 to Hl and R is displaced from Ro to R1. It can be changed arbitrarily like a pound.

In the embodiment described above, the angle of packet 4 is the fifth
The switching valve 22 shown in the figure must be manually operated to control the angle so that earth and sand will not spill from the packet 4.

Therefore, in order to perform complete turning trajectory control simply by operating the turning lever, a model link calculation mechanism as shown in FIG. 8 may be used.

In the drawings, the same reference numerals as in FIG. 2 indicate the same or corresponding parts.

This model link calculation mechanism is shown in Figure 2.
A link 14 is added to 1.

Actually, the line connecting point 237 and point T' shown in the figure corresponds to packet 4, but in order to simplify the link mechanism, P3'T' is placed on the opposite side of T' on the extension line of P3'T'. Considering a point τ' that becomes '2P3'τ', this T'' point moves on a trajectory x//f line that is parallel to a trajectory I'll do what I do.

Therefore, link 11
A slider 9 is pivotally attached to the tip 137 of the link 14, and a slider 9 is pivotally attached to the T'' point of the link 14, and this slider 9 is attached to the guide provided on the model link calculation mechanism along the X // X'' line. The member 12 is restrained from sliding in the groove.

In the model link calculation mechanism configured in this way, the link 14 corresponds to the packet 4, and the relative angle / between the slider 9 and the link 14 corresponds to the angle β between P3T and the trajectory XX line in FIG. .

This relative angle β' can be adjusted and fixed to a predetermined value by means such as bolts and nands.

Therefore, if β' is fixed at a predetermined value, when the tip T'' of the link 14 is on the X''X''X'' line, the link 14 will be
//Always maintain a predetermined angle to the X" line.

In FIG. 8, the upper and lower limit switches provided on the guide member 12 are omitted.

As in the case of the model link mechanism shown in FIG.
It is connected to a mechanism as shown in FIGS. 3 and 4 so as to move on the guide member 12 in proportion to the change in the relative displacement angle a of b.

FIG. 9 shows an embodiment of the present invention in which the packet cutting edge T of a hydraulic excavator is controlled to move on the XX-ray by a master-slave method using such a model link mechanism.

In the figures, the same reference numerals as in FIGS. 1, 5, and 8 indicate the same or corresponding parts.

In the figure, 31 indicates the model link mechanism of FIG. 8, and 2
2' Servo valve for operating the packet cylinder 7.

Packet rotation center point P3 and tip 137 of link 11
A detector such as a synchronizer or a potentiometer is provided at each point to detect the packet angle α3 and the relative displacement angle α3' of the link 14, and 25c compares the packet angle α3 and the link angle α3' and detects the difference. This is a servo amplifier that outputs an output in proportion to the difference and operates the servo valve 22'.

Reference numeral 26' indicates a changeover switch for switching the swing operation control between automatic and manual operation, and reference numeral 27c indicates a manual operation lever that generates an electric signal to operate the servo valve 22'.

The embodiments shown in FIGS. 8 and 9 will now be described in detail.

Immediately after excavation, the operator sets the switch 26' to the automatic position and operates the swing lever to swing the revolving structure 1a to the left or right depending on the position of the dump trunk 8.

As mentioned above, the slider 9 starts moving upward on the guide member 12 from the position indicated by the broken line in FIG. 8 in proportion to the change in the relative displacement angle, and therefore the TV point becomes x-/x. '／
Rise on the line.

At this time, the link 14 and the slider 9 are arranged in advance so that the link 14 and the x'Ixt line always maintain a predetermined relative angle β'.
and keep it fixed.

As the slider 9 moves, the link 10. Link 11 and link 14 are displaced, and each fulcrum P1', P2' and P3
Nine detectors detect each link angle α1', α2', α3'
Detects and sends electrical signals to servo amplifiers 25a, 25b
, 25c.

Also Pl. Each detector provided at P2 and P3 is α1. α
2 and α3 to detect the servo amplifiers 25a and 25b.
, 25c, and each servo amplifier sends an electric signal to α1 and α
1′.

α2 and α2' and α3 and α3' are compared, and an output is generated based on the difference to operate the servo valves 22', 23 and 24.

Therefore, boom cylinder 5, arm cylinder 6 and packet cylinder 7 are actuated, boom 2, arm 3 and packet 4 are activated, α1 and α1'α2, α2' and α3
and α3' are displaced so that they become equal.

Therefore, the packet cutting edge T moves on the trajectory XX line in proportion to the change in the relative displacement angle ■.

At this time, the angle β between the packet 4 and the trajectory XX line is always kept at a constant value, and is automatically controlled to an angle that prevents dirt from spilling from the packet 4.

The other functions are the same as those using the model link calculation mechanism shown in FIG.
By performing FF, it is possible to arbitrarily set a turning angle with respect to a fixed amount of movement of the bucket cutting edge T on the trajectory XX line.

Further, when setting the changeover switch 26' to the manual position, the operator operates the manual operation levers 27a, 27b, and 27c to control the boom 2, arm 3, and packet 4.
Needless to say, each of these can be operated independently to perform excavation work and other desired work operations.

Generally, the model link mechanism shown in FIG. 2 or FIG. 8 is preferably placed in the operator's cab to facilitate maintenance, inspection, and adjustment by the operator, but if there is a problem with space or other issues, it may be placed in an appropriate location in the hydraulic excavator main body 1. It may be placed in

According to the present invention described above, the following effects are achieved.

(1) It is possible to easily and safely control the turning trajectory of a hydraulic excavator, etc. when loading earth and sand into a dump truck, etc. by simply operating the turning lever and the switch that switches the turning trajectory control between automatic and manual.

(2J A model calculation mechanism that calculates and outputs the movement values of each link of the front attachment of a hydraulic excavator can be used to control the packet turning trajectory of a hydraulic excavator, etc., so it is possible to provide a low-cost control device. can.

[Brief explanation of the drawing]

Fig. 1 is a diagram illustrating the posture of the hydraulic excavator front attachment when loading earth and sand into a dump trunk with a hydraulic excavator, Fig. 2 is a diagram illustrating an example of the model link mechanism used in the present invention, and Fig. 3 4 is a front view showing a device that drives the model link mechanism, FIG. 4 is a sectional view taken along the line I-I in FIG. FIGS. 6 and 7 are diagrams explaining the relationship between the relative angle between the revolving body and the traveling body of the hydraulic excavator and the amount of movement of the front attachment, and FIG. 8 is another example of the model link mechanism. FIG. 9 is an explanatory diagram of a servo mechanism that controls a hydraulic excavator attachment by a master-slave method using the model link mechanism of FIG. 8. 1a: revolving body, 1b: traveling body, 2: boom, 3: arm, 4: packet, 5 nib cylinder, 6: arm cylinder, 7: packet cylinder, 8: dump truck, 9
: Slider, 10: Link corresponding to boom, 11: Link corresponding to arm, 12 Ni guide member, 14: Link corresponding to packet, 20: Changeover switch, 26: Changeover switch, Pl: Boom base end Pivot point 1, P2: Pivot point between the tip of boom 2 and arm 3, P3: Center point of packet rotation, Pl: Point corresponding to Pl, P2': Point corresponding to P2, P3'2 Point corresponding to P3 , T: Packet cutting edge, T'+T'' Point corresponding to 4 packet cutting edges, α1: Boom angle, α2: Arm angle, α,: Packet angle, α1': α
1, α2': link angle equivalent to α2, α3': link angle equivalent to α3, β: angle formed by a line connecting the packet rotation center point and the packet cutting edge with a predetermined locus.

Claims (1)

[Scope of Claims] 1. In a hydraulic soyobel or the like that controls the packet turning trajectory by suitably combining the displacements of the boom cylinder, arm cylinder, and packet cylinder and the rotational angle displacement of the turning motor, after excavation is completed, the turning body first turns to the left. Select whether to release soil after turning to the right or to release soil after turning to the right, specify the center of rotation of the packet or the direction of movement of the packet cutting edge on a preset linear trajectory, and then operate the swing lever to move the rotating body and traveling body. The relative displacement angle of the boom and the arm or the boom, the arm and the packet, in which the packet rotation center or the packet cutting edge should move on the preset linear trajectory from the position immediately after excavation according to this relative displacement angle. is calculated by a model calculation mechanism, and a state in which the packet rotation center or the packet cutting edge moves on the trajectory in proportion to the relative displacement angle by the output from the model calculation mechanism, and a state in which the rotating body turns independently. A turning trajectory control method for a hydraulic excavator, etc., characterized in that the turning trajectory of a packet is controlled by selectively instructing. 2. In a hydraulic excavator, etc. that controls the turning trajectory of the packet by combining the displacements of the boom cylinder, arm cylinder, and packet cylinder and the rotational angle displacement of the turning motor, the center of rotation of the packet or the straight line trajectory on which the packet cutting edge should work is set in advance. A boom and an arm, or a boom and an arm, in which the packet rotation center or the packet cutting edge moves on the preset linear trajectory from the position immediately after excavation in accordance with the relative displacement angle between the rotating body and the traveling body, which are displaced by the operation of a rotating lever. There is a model calculation mechanism that calculates each displacement of the packet, and by switching whether or not to operate this model calculation mechanism, the packet rotation center or the packet cutting edge is set to the above trajectory in proportion to the relative displacement angle based on the output from the model calculation mechanism. A switching means for selectively instructing a state in which the revolving body moves above the ground or a state in which the revolving body rotates independently, and a switching means for selecting and instructing a state in which the revolving body moves above the ground or a state in which the revolving body rotates independently, and a switching means that selects and instructs whether the revolving body rotates to the left and releases soil after turning to the left, or releases soil after turning to the right after excavation is completed. Alternatively, a turning trajectory control device for a hydraulic excavator or the like is provided, comprising a switching means for selecting and instructing the moving direction of the packet cutting edge on the preset linear trajectory. 3. A model link calculation mechanism similar to a front attachment of a hydraulic excavator, etc. is provided, and in the model link calculation mechanism, a point corresponding to the packet rotation center point on the model link calculation mechanism moves on a predetermined linear trajectory within the model plane. providing a guide member to restrain the packet rotation center point, and turning on a mechanism for moving a point corresponding to the packet rotation center point along the trajectory in proportion to a relative displacement angle between the rotating body and the traveling body and the model calculation mechanism; A changeover switch that turns OFF and a changeover switch that is switched depending on whether earth is released after turning left or earth is released after turning right, and the direction of movement of the point corresponding to the center point of packet rotation on the trajectory is kept constant; The hydraulic system according to claim 2, characterized in that the boom and arm and corresponding model links are connected by a servo mechanism that respectively displaces the boom angle and the arm angle to be equal to each model link angle. Turning trajectory control device for excavators, etc. 4 A model link calculation mechanism similar to a front attachment of a hydraulic excavator, etc. is provided, and the model link calculation mechanism is constrained so that a point corresponding to the packet cutting edge on the model link calculation mechanism moves on a predetermined linear trajectory within the model plane. A guide member is provided, and a mechanism is added to adjust and fix the angle between the model link corresponding to the packet and the trajectory to a predetermined angle, and the point corresponding to the packet cutting edge is set relative to the revolving body and the traveling body. The mechanism for moving along the trajectory in proportion to the displacement angle and the model calculation mechanism are turned ON and OFF.
A changeover switch that turns FF and a changeover switch that changes the direction of movement of the point corresponding to the packet cutting edge on the trajectory to a constant value depending on whether soil is released after turning left or soil is turned right after turning are provided, and the boom, arm, and Claim 2, characterized in that the packet and each corresponding model link are connected by a servo mechanism that respectively displaces the boom angle, arm angle and packet angle to be equal to each model link angle. Turning trajectory control device for hydraulic excavators, etc.