JP2739650B2 - Method and apparatus for applying tension to position detection wire of excavator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to
A method and apparatus for constantly applying a constant tension to a so-called position detection wire that is connected to an excavator to detect the position of the excavator in front, rear, right and left, torsion, etc. in order to ensure the verticality of the construction groove. Things.

[Conventional technology]

Conventionally, when excavating a construction trench such as a continuous underground wall using an excavator, a detection wire for detecting the excavation position of the excavator is vertically positioned between the excavator and a scaffold-shaped mount provided on the ground. The X-Y displacement meter is associated with the detection wire stretched vertically, and the displacement of the excavator caused by the excavation, that is, the displacement of the front-rear, left-right, twist, etc. is detected, and the detected data is used. Activate the stroke of the adjustable arm mounted on the front, rear, left and right sides of the excavator based on
2. Description of the Related Art It is known to provide a device for controlling the posture of an excavator so as to control the posture of the excavator so that a vertical construction groove can always be excavated.

[Problems to be solved by the invention]

By the way, it is necessary that the detection wire for detecting the displacement of the excavator such as front and rear, right and left, torsion, etc., that is, the excavation position, is always stretched with a constant tension in order to perform highly accurate attitude control.

Therefore, in the related art, a torque motor is associated with an unwinding and winding device for a detection wire provided on a gantry side, and a constant tension is always applied to the detection wire by the torque motor. However, the method using the torque motor has the following problems.

(1) First, the torque generated by the torque motor for applying tension to the detection wire is always constant in principle.
On the other hand, the detection wire becomes longer according to the excavation work of the excavator. Therefore, there is no problem if the detection wire is always maintained at a fixed length, but if the excavation operation proceeds and the length of the detection wire changes, that is, if the excavator goes deep into the ground and the detection wire becomes longer. If this happens, the tension applied to the detection wire becomes relatively weak.

In particular, in the case of deep excavation at an excavation depth of 100 meters or more, since the excavation is also affected by muddy water flow containing a stable liquid filled in the excavation groove, the horizontal position of the detection wire measured by the XY displacement meter is measured. An error occurs in the displacement amount.

As a result, it is difficult to accurately detect the tilt of the excavator,
There was a problem that proper posture control of the excavator could not be performed. That is, there has been a defect that high-accuracy attitude control cannot be performed.

Therefore, in the case of deep excavation as a means for suppressing this disorder, it has been attempted to use a large torque motor, increase the tension applied to the detection wire, and eliminate the influence from muddy water flow and the like. However, when the torque motor is enlarged and a torque control system is introduced, not only is the device complicated, but also its reliability and economy are problematic, and it has not been possible to find an appropriate solution.

(2) Next, when tension is applied by the torque motor, the motion of the torque motor is not completely statically constant. Therefore, there is some discontinuity in unwinding the detection wire, the detection wire oscillates in the vertical direction, and an error occurs in the value detected by the XY displacement meter. There is a problem that the attitude control of the robot cannot be performed.

(3) Since the excavator to which the detection wire is further connected is affected by the excavation speed due to the geological conditions of the ground to be excavated,
During excavation work, it may drop or rise sharply. That is, the excavation speed may change rapidly.

There is no problem if the torque motor can respond appropriately to this change.However, if there is a delay, the detection wire will be cut off by applying abnormal tension to the detection wire or, conversely, will loosen. There was also a problem that trouble was caused by being turbulently wound by the winding drum.

In any case, the conventional method of applying tension to the detection wire using the torque motor has a problem in reliability and economy in performing appropriate posture control of the excavator.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method and an apparatus for always applying an appropriate tension to a detection wire in order to detect a position of an excavator which has solved the problems of the related art.

[Means for solving the problem]

The method and apparatus adopted by the present invention as means for achieving the above object are as follows.

First, a detection wire unwinding and winding device is provided on a ground mount, and the detection wire is vertically connected to the excavator from the unwinding and winding device, and the horizontal displacement of the detection wire connected to the vertical is XY displacement. In a trench excavator for construction, such as a continuous underground wall, which is configured to control the excavation posture of the excavator based on the detected data, a detection wire from the unwinding and winding device is connected to the ground mount. Attached to the excavator via sheaves and sheaves provided on the upper left and right sides, a counterweight type tension applying device was suspended on the detection wire between the left and right sheaves, and the suspended tension applying device was set in advance. When ascending to the upper limit position, the detection wire is unwound at a speed higher than the excavation speed of the excavator by operating the unwinding and winding device for the detection wire, and conversely lowers to the lower limit position. The operation of the unwinding and winding device is stopped, and the unwinding and winding device of the detecting wire is repeatedly operated and stopped in the manner described above so that a constant tension is always applied to the detecting wire. .

Further, as means for repeatedly operating and stopping the unwinding and winding device of the detection wire, an elevating guide rail of a tension applying device is provided on both sides of the ground mount, and the tension applying device is provided on upper and lower portions of the elevating guide rail. An upper limit switch and a lower limit switch that are turned on and off when the ascending and descending operations are provided, respectively, and the upper limit switch and the lower limit switch function as an ON-OFF control switch of the unwinding and winding device of the detection wire. It is assumed that.

That is, an apparatus configuration is provided in which the ON / OFF control switch of the unwinding / winding device for the detection wire is provided on the upper and lower portions of the lifting guide rail of the tension applying device.

Further, the tension applying device is characterized in that a plurality of divided weights are loaded and configured as a tension applying device capable of adjusting the weight.

[Action]

Since the method and apparatus for applying tension to the detection wire according to the present invention is a counterweight type tension applying method as described above, the tension applied to the detection wire is always kept constant according to its weight. .

More specifically, the operation of this point will be described first. When the excavation operation is started and the excavator descends, the tension applying device suspended on the detection wire relatively rises. At this time, the detecting wire is maintained at a constant tension by the weight of the tension applying device.

When the tension applying device rises, that is, the excavation work proceeds, and the tension applying device comes to the set upper limit position, the upper limit switch is operated, and the detection wire unwinding device is operated to excavate the detection wire. Unwind at a speed higher than the excavation speed of the machine.

Then, the tension applying device is relatively lowered by its weight. Then, when the tension applying device is lowered to the lower limit position, the lower limit switch is operated, and as a result, the unwinding and winding device of the detection wire stops operating. Hereinafter, as the excavation work progresses, the tension applying device repeats the up and down operation, and during that time, a constant tension is always applied to the detection wire.

That is, the detection wire is held at a predetermined tension without slackening or vertical deflection. As a result, the values measured by the XY displacement meter do not become out of order, the appropriate control of the posture of the excavator can be always performed, and the excavation of the vertical construction groove can be performed.

Also, since the weight of the tension applying device is adjustable,
If the excavation depth is 100 meters or more and there is a risk of the influence of stable liquid, that is, if the length of the detection wire is long, adjust the weight so that appropriate tension can be applied according to the length. Just do it.

When the excavation work is completed and the excavator is to be lifted,
The tension of the sensing wire is not a problem. Therefore, contrary to the excavation work, the lower limit switch may be switched so that the lower limit switch is operated when the tension applying device is lowered to the lower limit position to perform the winding operation of the detection wire.

〔Example〕

Further, the configuration of the method and the apparatus of the present invention will be specifically described based on embodiments shown in the drawings.

First, FIG. 1 shows a main part of an apparatus for carrying out the method of the present invention. FIG. 2 shows a state in which a winding device 3 and a counterweight type tension applying device 4 for applying an appropriate tension to the detection wire 2 are suspended. In the embodiment, as shown in this figure, the unwinding and winding device 3 for the detection wire 2 uses a general winch. Then, the detection wire 2 from the winch is vertically hung down via a reversing sheave 5 and a top sheave 6 provided on the upper left and right sides of the gantry 1, and its terminal is connected to an excavator (not shown). Next, a counterweight type tension applying device 4 is suspended between the reversing sheave 5 and the top sheave 6 via a suspension sheave 7.

The tension applying device 4 includes a weight mounting base 4b formed of a box-shaped frame 4a, and on the weight mounting base 4b,
A plurality of weights 8 divided into a fixed weight are mounted in a stacked manner so that the weight of the tension applying device 4 can be adjusted appropriately.

Further, guide rails 9 and 9 for raising and lowering the tension applying device 4 are provided on both left and right sides of the gantry 1, and the tension applying device 4 is configured to perform the raising and lowering operation via the guide rollers 10 and 10. An upper limit switch 11 is provided above the guide rail 9 and a lower limit switch is provided below the guide rail 9.
When the tension applying device 4 ascends and reaches the position of the upper limit switch 11, the upper limit switch 11 causes the unwinding and winding device 3, that is, the winch of the detection wire to operate, and the detection wire 2 is moved to the excavator. It is configured so that it can be fed at a speed higher than the excavation speed.

Conversely, when the tension applying device 4 is lowered to the position of the lower limit switch 12, the operation of the winch is stopped.

In the embodiment, the upper limit switch 11
An upper limit alarm limit switch 11a and a lower limit alarm limit switch 12a are provided above and below the lower limit switch 12 for safety, respectively, to ensure the safety of the device.

Further, a cushioning material 13 is provided on the bottom of the gantry 1 so as to function as a shock absorber so that it is safe even if the tension applying device 4 falls down.

Next, the operation state will be described with reference to FIGS. First, FIG. 2 shows the position of the tension applying device 4 immediately after the start of the excavation operation. As the excavation operation proceeds, the tension applying device 4 further rises. When the upper limit switch 11 rises to the height position shown in FIG. 3, the upper limit switch 11 is operated, and the detection wire 2 is fed out at a speed higher than the excavating speed of the excavator. As a result, the tension applying device 4 relatively lowers. FIG. 4 shows the tension applying device 4.
Shows a state in which the lower limit has been lowered to the position of the lower limit switch 12.

When the tension applying device 4 comes to this position, the lower limit switch 12 is operated, and the operation of the winch that has been feeding out the detection wire 2 is stopped. When the winch stops, the tension applying device 4 rises again with the excavation work.

Hereinafter, as the excavation work progresses, the tension applying device repeatedly moves up and down, and during that time, constantly applies a constant tension to the detection wire 2 in accordance with the weight of the tension applying device 4, and as a result, there is no error, that is, accuracy. X- of high detection wire 2
Measure the Y displacement to ensure proper control of the excavator attitude.

In the case of a deep excavation with an excavation depth of 100 meters or more, the length of the detection wire and a corresponding tension capable of eliminating the influence of the stable liquid or the like in the excavation groove are given to the detection wire 2 in advance. The weight of the tension applying device 4 is adjusted. (See FIG. 5) [Effects of the Invention] In the present invention, since the tension applied to the detection wire is applied by the counterweight method as described above, the following effects are exhibited as compared with the conventional application method using a torque motor. Is done.

(1) Since the weight of the weight can be freely adjusted, that is, by increasing or decreasing the number of weights, an optimum tension can always be applied to the detection wire.

As a result, the displacement measurement of the detection wire with high accuracy is maintained, the position of the excavator can be detected accurately, the posture of the excavator can be controlled properly, and a deep trench such as a vertical continuous underground wall is excavated. can do.

(2) Because of the counterweight method, the configuration as a tension applying device is simple, and it is much more economical than a torque motor.

(3) Since the lifting and lowering operation of the tension applying device is perfectly synchronized with the movement of the excavator, a constant tension is always applied to the detection wire, and the displacement measurement result of the detection wire has no error, and the posture control of the excavator is appropriate. , And high-precision excavation of the construction groove is guaranteed.

(4) There is no trouble such as cutting of the detection wire or turbulence of the wire drum as seen when a torque motor is used. Therefore, reliability, workability,
Maintainability is improved.

[Brief description of the drawings]

FIG. 1 is a mechanism diagram showing a main part of an apparatus for carrying out the method of the present invention. FIG. 2 is a diagram showing a state in which the tension applying device is performing an ascent operation at the start of excavation work, FIG. 3 is a diagram showing a state in which the tension applying device is elevated to a position of an upper limit switch,
Fig. 4 shows the detection wire unwinding and rewinding device being activated by the operation of the upper limit switch (ON), and the detection wire is extended. The tension applying device is lowered to the lower limit switch (OFF) position, and the detection wire is extended. FIG. 5 is a front view of the device when the excavation depth is large and the length of the detection wire is long, and when the weight adjustment of the tension applying device is performed. DESCRIPTION OF SYMBOLS 1 ... Stand, 2 ... Detection wire 3 ... Unwinding and winding device (winch) of detection wire 4 ... Tension applying device, 5 ... Reversing sheave 6 ... Top sheave, 7 ... Hanging sheave 8 ... Weight 9 Guide rail 10 Guide roller 11 Upper limit switch 12 Lower limit switch

Claims (2)

(57) [Claims] A detection wire is vertically extended between an excavator for excavating a construction groove such as a continuous underground wall and a ground stand, and the XY displacement of the vertically extended detection wire is measured. In an excavator such as a continuous underground wall that detects and controls the attitude of the excavator based on the detection data, the detection wire is passed through two sheaves from an unwinding and winding device provided on a ground mount. Connected to the excavator, a counterweight type tensioning device is suspended between the two sheaves, and the tensioning device rises with the excavation work,
When the upper limit position is reached, the detection wire unwinding and winding device is operated to unwind the detection wire at a speed higher than the excavation speed, and when the lower limit position is reached, the detection wire unwinding and winding device is used. A method of applying tension to a position detection wire of an excavator, wherein the operation is stopped, and the above operation is repeated to constantly apply a constant tension to the detection wire based on the weight of the tension applying device. . 2. A sheave is provided on the left and right of the upper part of the ground stand, a detection wire is connected to an excavator from an unwinding and rewinding device via the right and left sheaves, and a weight adjustable tension loaded with a plurality of divided weights is loaded. An application device is suspended on a detection wire between the left and right sheaves, and a lifting guide rail of the tension application device is provided on the ground stand, and the detection wire is unwound and wound on the upper and lower portions of the elevation guide rail. A tension applying device for a position detecting wire of an excavator, comprising a switch for ON-OFF control of the device.