JPH076213B2 - Drilling rig with grab bucket - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavator which is mainly mounted on a dredging ship and has a grab bucket for excavating the seabed or the like.

[0002]

2. Description of the Related Art An excavator having a grab bucket moves a grab bucket up and down with a support wire and opens and closes a shell of the grab bucket with an opening and closing wire. The grab bucket is raised or lowered by winding or unwinding the support wire. Further, the opening / closing wire is wound around or unwound on the support wire to open / close the shell of the grab bucket. The excavator having this structure is used as follows.

The grab bucket is moved above the excavation position. Loosen the open / close wire and open the grab bucket shell. Pull out the support wire and drop the grab bucket in an open position. Wind the open / close wire, close the shell of the grab bucket, and scoop up the soil. Take up the support wire and lift the grab bucket to carry it into place. Suspend the grab bucket above the carrier and open the shell to drop the earth and sand.

The excavator used in this state has an extremely large impact when the support wire is loosened and the grab bucket is opened. This is because when the support wire is loosened, the extremely heavy shell opens while accelerating under its own weight, and suddenly stops moving when it is completely open. The impact of the grab bucket gives a strong shock to the moving parts of the shell, and seriously damages the grab bucket.

The impact of opening the grab bucket can be eliminated by braking the feeding of the support wire. While the shell is being opened, the brake of the open / close drum can be operated to reduce the speed at which the open / close wire is paid out. Further, by operating the brake of the opening / closing drum immediately before the shell is completely opened, the impact when the grab bucket is completely opened and stopped can be reduced.

[0006]

However, in reality, while the operator watches the opening of the grab bucket,
Accurate braking of the open / close drum is a difficult technique. This is because there is a time delay in braking the grab bucket due to the looseness of the open / close wire. Even if the grab bucket is fully opened and the brake is operated immediately before that, the shell continues to open until the looseness of the open / close wire extends, and braking cannot be performed immediately before the shell opens. For this reason, it is extremely difficult for the conventional excavator having a grab bucket to reduce the impact when the shell of the grab bucket is opened, and the impact damages the grab bucket, shortens its life, and makes maintenance troublesome. There was such a drawback.

The present invention was developed for the purpose of solving this drawback, and an important object of the present invention is to reduce the shock when the shell is opened and to prevent the operator from performing a difficult operation. An excavator having a bucket is provided.

[0008]

An excavator having a grab bucket according to the present invention has the following structure in order to achieve the above object. That is, the excavating device includes a grab bucket 1 to be excavated and a shell 1A of the grab bucket 1.
Opening / closing wire 2 for opening / closing, supporting wire 4 for raising / lowering grab bucket 1, opening / closing drum 7 for winding opening / closing wire 2, brake 9 for controlling rotation of opening / closing drum 7, and supporting drum for winding support wire 4 10 and
A power source 8 for driving the open / close drum 7 and the support drum 10 is provided.

The open / close wire 2 is connected with an open / close sensor 3 for directly or indirectly detecting the movement amount thereof, and the support wire 4 is connected with a support sensor 5 for directly or indirectly detecting the movement amount thereof. Further, the device of the present invention is a control means 6 for calculating the opening degree of the grab bucket 1 from the input signals from the opening / closing sensor 3 and the support sensor 5.
Is equipped with. The control means 6 detects the opening degree of the grab bucket 1 and controls the brake 9 while the shell 1A of the grab bucket 1 is being opened to temporarily brake the rotation of the opening / closing drum 7 to open the shell 1A. Slow down.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. However, the embodiments shown below exemplify an excavation device having a grab bucket for embodying the technical idea of the present invention, and the excavation device of the present invention is made of material, shape, structure of components, The arrangement is not specific to the structure below. The excavating device of the present invention is subject to various modifications within the scope of claims.

Further, in this specification, for easier understanding of the claims, the numbers corresponding to the members shown in the embodiments are referred to as "claims column" and "to solve conventional problems." It is added to the members shown in the column of "means for performing".
However, the members shown in the scope of claims are not limited to the members of the embodiments.

2 and 3 show a dredger equipped with a drilling rig with grab buckets. This excavator is equipped with a drilling device that winds a grab bucket 1 for excavating the seabed, an opening / closing wire 2 for opening / closing a shell 1A of the grab bucket 1, a support wire 4 for moving the grab bucket 1 up and down, and an opening / closing wire 2. Opening / closing drum 7 and supporting drum 10 for winding the supporting wire 4
A power source 8 for driving the open / close drum 7 and the support drum 10, a support sensor 5 for detecting the amount of extension of the support wire 4, and an open / close sensor 3 for detecting the amount of extension of the open / close wire 2.

As shown in FIGS. 2 and 4, the grab bucket 1 is formed by connecting two wires, an open / close wire 2 and a support wire 4. Opening / closing wire 2 is shell 1A
Open and close. That is, the shell 1A is closed by pulling the open / close wire 2 without moving the support wire 4. On the contrary, if the opening / closing wire 2 is paid out without moving the support wire 4, the shell 1A is opened.

The opening degree of the shell 1A is determined by the pulling amount of the opening / closing wire 2 with respect to the support wire 4. In other words, the shell 1A is opened and closed by the relative movement of the opening / closing wire 2 and the supporting wire 4. When the opening / closing wire 2 and the supporting wire 4 are moved together, the glove bucket 1 moves up and down without the shell 1A performing opening / closing movement.

As shown in FIG. 4, the opening / closing wire 2 is connected to a bent portion at the center of the shell 1A via a pulley. When the opening / closing wire 2 pulls up the central portion of the shell 1A, the shell 1A is closed. If the opening / closing wire 2 does not pull up the central portion of the shell 1A, the shell 1A is opened by its own weight as shown in FIG. Two shells 1A
Are connected so that they can be bent at the central portion, as shown in FIG.

The opening of the shell 1A is detected by the control means 6 which operates the open / close sensor 3 and an input signal from the open / close sensor 3. A block diagram of the control means 6 is shown in FIG. The control means 6 shown in this figure detects the opening of the shell 1A, controls the brake 9 at a predetermined position, brakes the feeding of the opening / closing wire 2, and controls the opening movement of the shell 1A. That is, at a predetermined position in the middle of opening the shell 1A by pulling out the opening / closing wire 2,
The brake 9 is operated to slow down the rotation of the open / close drum 7, and the shell 1A is braked so as not to open suddenly.

In order to control the rotation of the open / close drum 7, the excavator is provided with an open / close sensor 3 for detecting the amount of movement of the open / close wire 2 for opening / closing the grab bucket 1, as shown in FIG.
A support sensor 5 for detecting the amount of movement of the support wire 4 for moving the grab bucket 1 up and down, a control means 6 for computing the input signals from both sensors and calculating the opening of the grab bucket 1, and a control means 6. Controlled by the open / close drum 7
And a brake 9 for braking.

As the opening / closing sensor 3, all sensors which can directly or indirectly detect the movement amount of the opening / closing wire 2 can be used. As the opening / closing sensor 3 that directly detects the amount of movement of the opening / closing wire 2, a sensor that detects the rotation of a roller that rotates in contact with the opening / closing wire 2 can be used.
As a sensor for indirectly detecting the movement amount of the opening / closing wire 2, for example, a sensor for detecting the rotation of the winding drum of the opening / closing wire 2 can be used.

As the support sensor 5, as with the open / close sensor 3, all the sensors capable of directly or indirectly detecting the movement amount of the support wire 4 can be used. As the sensor that directly detects the movement amount of the support wire 4, a sensor that detects the rotation of the roller that rotates in contact with the support wire 4 can be used. As a sensor that indirectly detects the movement amount of the support wire 4, for example, a sensor that detects the rotation of the winding drum of the support wire 4 can be used.

The control means 6 calculates the opening degree of the shell 1A of the grab bucket 1 from the input signals from the open / close sensor 3 and the support sensor 5. A microcomputer is used as the control means 6. The microcomputer includes an A / D converter 6A that converts an analog signal input from the opening / closing sensor 3 and the support sensor 5 into a digital signal,
A CPU 6B that calculates the opening of the shell 1A by calculating the input signals from both sensors, a function that calculates the opening of the shell 1A from the input signals from both sensors, and a memory 6C that stores the operation information of the brake 9. Is equipped with.

The opening of the shell 1A is determined by the amount of extension of the opening / closing wire 2 with respect to the support wire 4. Therefore, the memory 6C includes the open / close sensor 3 and the support sensor 5.
It stores a function for calculating the opening of the shell 1A from the difference between the input signals of. The memory 6C also stores brake information about how much the brake 9 is applied to brake the feeding of the opening / closing wire 2 when the shell 1A of the grab bucket 1 is opened. Brake operation of the opening / closing drum 7 is preferably 2 to 3 during the opening movement of the shell 1A.
It is good practice to apply the brake 9 for a short time at three places, and apply the brake 9 continuously at the end of the shell 1A completely opening.

The drooping machine which replaces and uses a plurality of grab buckets 1 has a function for calculating the openings of the shells 1A of all the grab buckets 1 to be replaced and the optimum brake information for the grab buckets 1. Are stored in the memory 6C, and when the grab bucket 1 is replaced, the function and the brake information corresponding to the replaced grab bucket 1 are switched.

The CPU 6B calculates the opening of the shell 1A from the function of storing the signal input from the A / D converter 6A in the memory 6C, and operates the brake 9 when the shell 1A is opened at a predetermined angle. Then, the rotation of the open / close drum 7 is braked.

The brake 9 is provided with a disc brake which is a braking member 9A for braking the rotation of the open / close drum 7, and a drive member 9B for driving the caliper of the disc brake to adjust the braking force of the disc brake. .

The disc brake, which is the braking member 9A, is
As shown in FIG. 2, a disc fixed to both sides of the opening / closing drum 7 and a caliper for sandwiching the disc and braking the rotation of the disc are provided.

The drive member 9B includes a hydraulic piston 12 for adjusting the disc stopping force, a control valve 13, and a switching valve 14.
And a hydraulic pump 11. Hydraulic piston 12
When is pushed out by hydraulic pressure, the caliper clamps the disc and brakes the rotation of the disc.

The control valve 13 is controlled by the CPU 6B. That is, the opening degree of the control valve 13 is controlled by the CPU 6B.
The control valve 13 bypasses the hydraulic pressure supplied from the switching valve 14 to the hydraulic piston 12.

As the opening degree of the control valve 13 increases, a large amount of hydraulic pressure is bypassed and the hydraulic pressure supplied to the hydraulic piston 12 is reduced, and the force with which the hydraulic piston 12 presses the caliper becomes weaker. When the pressing force of the caliper becomes weak, the disc easily rotates, that is, the brake 9 is released, and the open / close drum 7 easily rotates.

On the contrary, as the control valve 13 is closed, the hydraulic pressure acting on the hydraulic piston 12 becomes higher, and the hydraulic piston 12 presses the caliper with a stronger force against the disc. In this state, the brake 9 is strongly closed, and the rotation of the open / close drum 7 is more strongly braked.

The switching valve 14 is in the position shown in FIG. 1 when the shell 1A of the grab bucket 1 is not braked. In this state, the hydraulic oil pressurized by the hydraulic pump 11 is not supplied to the hydraulic cylinder. Therefore, the brake 9 does not brake the rotation of the open / close drum 7. When the shell 1A of the grab bucket 1 is opened to a predetermined opening, the switching valve 1
4 is switched from the position of FIG. When the switching valve 14 is switched, the hydraulic pump 11 supplies hydraulic oil to the hydraulic cylinder. In this state, the opening degree of the control valve 13 is adjusted and the braking force of the shell 1A of the grab bucket 1 is adjusted.

[0031]

INDUSTRIAL APPLICABILITY The excavator having a grab bucket according to the present invention can open the shell of the grab bucket in an ideal state even if the operator is not required to have a high level of operation skill, and the grab bucket is completely opened and stopped. It has the feature of significantly reducing the impact when doing. This feature is because the opening amount of the shell is calculated by detecting the feeding amount of the open / close wire and the support wire by the open / close sensor and the support sensor, and the support drum is braked in a state optimal to the opening of the shell. The relative feeding amount of the opening / closing wire and the supporting wire accurately specifies the opening degree of the shell. Therefore, the excavating device of the present invention that detects the amount of the open / close wire fed out with respect to the support wire and brakes the open / close drum has the shell accurately at a predetermined angle even if the support wire and the open / close wire are loose. Is braked. In other words, the looseness of the support wire and opening / closing wire does not disturb the braking position of the shell. This is because the amount of feeding of the opening / closing wire with respect to the support wire determines the opening degree of the shell.

Further, in the excavator having the grab bucket of the present invention, in order to reduce the shock of the shell, it is not necessary for the operator to operate the brake by looking at the opening of the shell. Therefore, the operator is not required to have a high level of operation skill, and the shell is opened in an ideal state to reduce the impact, thereby prolonging the life of the grab bucket and simplifying the maintenance.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of control means of an excavator according to the present invention.

FIG. 2 is a side view showing a dredging ship in which an excavator is set.

FIG. 3 is a plan view showing a supporting drum and an opening / closing drum portion of the dredger shown in FIG.

FIG. 4 is a side view showing an example of a shell.

[Explanation of symbols]

1 …… Grab bucket 1A …… Shell
2 ... Open / close wire 3 ... Open / close sensor 4 ... Support wire
5 ... Support sensor 6 ... Control means 6A ... A / D converter 6B ... CPU 6C ... Memory
7 ... Opening / closing drum 8 ... Power source 9 ... Brake
9A ... braking member 9B ... driving member 10 ... support drum
11 ... hydraulic pump 12 ... hydraulic piston 13 ... control valve
14 ... Switching valve

Claims (1)

[Claims] 1. A grab bucket (1) to be excavated and an opening / closing wire (2) for opening and closing a shell (1A) of the grab bucket (1).
And support wires (4) that raise and lower the grab bucket (1)
An open / close drum (7) that winds the open / close wire (2), a brake (9) that controls the rotation of the open / close drum (7), a support drum (10) that winds the support wire (4), and an open / close drum In an excavator having a grab bucket equipped with a power source (8) for driving (7) and a supporting drum (10), an opening / closing wire (2) has an opening / closing sensor (directly or indirectly) for detecting the movement amount thereof. 3) are connected and support wire
A support sensor (5) that directly or indirectly detects the movement amount is connected to (4), and the opening degree of the grab bucket (1) is determined from the input signals from the opening / closing sensor (3) and the support sensor (5). Is equipped with a control means (6) for calculating, and the control means (6) detects the opening degree of the grab bucket (1) and controls the brake (9) while the shell (1) of the grab bucket is being opened. An excavator having a grab bucket, which is configured to temporarily brake the rotation of the opening / closing drum (7) to reduce the speed at which the shell (1A) is opened.