JP3086413B2 - Hydraulic circuit of gripper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to the construction of a pile,
The present invention relates to a hydraulic circuit of a gripping device used in an erection demolition machine that performs demolition.

[0002]

2. Description of the Related Art When performing underground construction such as subway construction or construction on a basement floor of a building, an erection demolition machine is used to prevent swelling and collapse of piles for retaining soil such as sheet piles buried in a wall. The erection and dismantling of the section steel that supports the pile by erection in the excavated underground space is performed. At the tip of the arm of the hydraulic excavator of the construction demolition machine, a gripping device equipped with a hydraulically drivable cylinder is mounted so as to be able to move up, down, back and forth, and rotatably. The work is carried out by gripping and moving the gripped steel mold up and down, back and forth, and rotation. An accumulator is connected to a pipeline for supplying pressure oil to the bottom chamber of the cylinder of the gripping device, and when pressure oil is not supplied to the bottom chamber of the cylinder of the gripping device for some reason, the accumulator is connected to the bottom chamber. The configuration is such that the mold steel gripped by applying pressure is prevented from being released from the gripping device.

[0003]

However, when the work is carried out while gripping the shape steel by such a gripping device, since the gripping device moves or rotates in various directions, a pressure is applied to the cylinder of the gripping device. The pipeline may be damaged due to excessive force applied to the pipeline such as a hose for supplying oil. If the pipeline between the hydraulic source and the accumulator is broken, the accumulator prevents the release of the gripping device.However, if the pipeline between the accumulator and the cylinder is broken, pressurized oil flows into the cylinder. No longer supplied, the gripping force of the gripping device is reduced.

[0004] It is an object of the present invention to provide a hydraulic circuit of a gripping device capable of holding the gripping force of the gripping device even if the pressure oil line between the hydraulic source and the gripping device is broken. To provide.

[0005]

FIG. 1 shows an embodiment of the present invention.
The present invention will be described with reference to FIGS. 4 to 4. The present invention according to claim 1 comprises at least one telescopic cylinder 1 that expands and contracts with hydraulic oil from a hydraulic pressure source 10 to drive a grip portion 54.
And a bottom chamber 1a and a rod chamber 1b of the telescopic cylinder 1.
Supply of pressure oil to the bottom chamber 1a in a hydraulic circuit of a gripping device provided with a switching valve SV2 for switching the direction of pressure oil guided to the cylinder and an accumulator ACC for supplying pressure oil to the bottom chamber 1a of the telescopic cylinder 1. A pilot operated check valve PC for permitting and preventing the outflow of pressurized oil from the bottom chamber 1a and permitting the outflow of pressurized oil from the bottom chamber 1a only when the pressurized oil is supplied to the rod chamber 1b; A first oil pump, which is provided in parallel with a pilot operated check valve PC and connected in series with each other, allows supply of pressure oil to the chamber 1a and prohibits outflow of pressure oil from the bottom chamber 1a.
And second check valves CV1 and CV2,
The above object is achieved by providing an accumulator ACC connected between the first and second check valves CV1 and CV2.

In the hydraulic circuit of the gripping device according to the present invention, when the gripping portion 54 grips, the pressure oil from the hydraulic pressure source 10 switches the switching valve SV2, the pilot operated check valve PC and the first and second check valves CV1 and CV2.
Is supplied to the bottom chamber 1a of the telescopic cylinder 1 through which the cylinder 1 is extended and gripping is performed. At the same time, the pressure oil is supplied to the accumulator ACC, and the pressure oil is accumulated in the accumulator ACC. If the pipeline for supplying pressure oil from the hydraulic pressure source 10 to the bottom chamber 1a during gripping is broken, the pressure oil from the accumulator ACC is supplied to the bottom chamber 1a, so that the cylinder 1 does not contract and the gripped object Is securely held. On the other hand, even if the line for supplying the pressure oil from the accumulator ACC to the bottom chamber 1a is broken, the pressure oil from the hydraulic pressure source 10 is supplied to the pilot operated check valve PC and the first and second check valves CV.
Since the cylinder 1 is supplied to the bottom chamber 1a via the CV1 and CV2, the cylinder 1 does not shrink, and similarly the object is surely gripped. When the cylinder 1 is contracted, the switching valve SV2 is switched, the pressure oil from the hydraulic pressure source 10 is supplied to the rod chamber 1b of the cylinder 1, and the pressure oil in the bottom chamber 1a is released via the pilot operated check valve PC. Therefore, the cylinder 1 contracts and the gripping part is released.

In the section of the means for solving the above-mentioned problems, which explains the configuration of the present invention, the drawings of the embodiments of the present invention are used to make the present invention easy to understand. However, the present invention is not limited to this.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit diagram of a hydraulic circuit of a gripping device according to the present invention, FIG. 2 is a side view showing an embodiment of an erection demolition machine to which the hydraulic circuit of the gripping device according to the present invention is applied, and FIG. Plan view of the construction demolition machine in the form of
FIG. 3 is a partial cross-sectional side view of the gripping device of the construction and demolition machine of the embodiment of FIG. First, the configuration of the erection demolition machine will be described with reference to FIGS.

As shown in FIGS. 2 and 3, the excavator body 23 is constructed by installing an upper revolving unit 22 on a lower traveling unit 20 via a revolving unit 21. 2
Reference numeral 4 denotes a bracket fixedly installed on the upper revolving unit 22, and when used as a hydraulic excavator, the boom and the boom cylinder are connected by pins. In this embodiment, a pin hole of the bracket 24 is used. The mast 25 is replaceably attached to a boom or a boom cylinder by means of pins 26 and 27.

A telescopic arm 30 is mounted on the top of the mast 25 by a hydraulic cylinder 29 for raising and lowering around a pin 28a. More specifically, the telescopic arm 3
0 is attached to the upper part of the outer cylinder 25b by a pin 28a,
The tube end of the elevating cylinder 29 is attached to the lower part of the outer cylinder 25b with a pin 28b. The telescopic arm 30 is a mast 2
5, an outer cylinder 32 connected to the outer cylinder 3 by a pin 28a.
2 comprises an inner cylinder 31 slidably fitted to 2 and a telescopic hydraulic cylinder 33 incorporated therein. The base end of the telescopic hydraulic cylinder 33 is the outer cylinder 32, and the piston rod is the inner cylinder 31.
Connected to each other. The stroke of the telescopic arm 30 is set to be larger than the amount of movement that can release the mold steel from the state where the mold steel is gripped, that is, the width of the mold steel.

An inner cylinder 31 of the telescopic arm 30 accommodates a hydraulic cylinder 41 for swinging up and down, which will be described later. The base end of the hydraulic cylinder 41 is connected to the inner cylinder 31, and the piston rod is connected to a link 75 which will be described later.

As shown in FIGS. 2 and 3, the gripping device 3 is attached to the tip of the telescopic arm 30, that is, the tip of the inner cylinder 31.
4 is attached via a vertical swing device 35, a left and right swing device 36, and a swivel device 37. The vertical oscillating device 35 is connected to a bracket 38 attached to the distal end of the inner cylinder 31 of the telescopic arm 30, a bracket 40 attached to the bracket 38 so as to be movable up and down around a pin 39, and the brackets 38 and 40. A link mechanism 75;
It comprises a hydraulic cylinder 41 for swinging up and down mounted between the link mechanism 75 and the inner cylinder 31.

As shown in FIGS. 2, 3 and 4, the left and right swinging device 36 includes a bracket 43 mounted on a bracket 40 so as to be able to swing left and right around a pin 42, and the brackets 40 and 43. The bracket 43 swings left and right by extending one of the left and right swing cylinders 44 and 45 and simultaneously contracting the other of the left and right swing cylinders 44 and 45. is there.

As shown in FIG. 4, the turning device 37 includes an outer ring 46 mounted on a bracket 43 of the left and right swinging device 36.
An inner ring 47 that is rotatably mounted on the inner periphery of the outer ring 46 and has an internal gear, a hydraulic motor 48 for rotation mounted on the bracket 43, and an output shaft of the rotation motor 48. It comprises a pinion 49 meshing with the internal gear and a turning frame 50 fixed to the inner ring 47.

As shown in FIGS. 2, 3 and 4, the gripping device 34 includes side plates 51 fixedly mounted on both sides of the revolving frame 50, fixed claws 52 mounted on the lower portion of each side plate 51, respectively. The movable pawl 54 is attached to the top of each side plate 51 via a parallel link mechanism 53, and a hydraulic cylinder device 62 for opening and closing the movable pawl 54. The side plate 51, the fixed claw 52, the parallel link mechanism 53, the movable claw 54, and the opening / closing hydraulic cylinder device 62 are provided as a set as shown in FIG. The parallel link mechanism 53 is connected to each side plate 51.
And links 57 and 58 rotatably attached to pins 55 and 56, respectively, and a bracket 61 which is rotatably connected to tips of the links 57 and 58 by pins 59 and 60 and is integral with the movable claw 54. Consisting of pins 55 and 5
The line connecting 6,59,60 forms a parallelogram. The opening and closing hydraulic cylinder device 62 is provided between the extending portion of the link 57 rearward and the turning frame 50.

As shown in FIG. 1, a hydraulic circuit for driving an opening / closing hydraulic cylinder device 62 for driving a movable claw 54 of a gripping device 34 includes two opening / closing hydraulic cylinder devices 62.
A hydraulic pump 10 for supplying hydraulic oil to the pump, a first solenoid valve SV1 for controlling the flow of hydraulic oil from the hydraulic pump 10 into the tank T, and a hydraulic cylinder device 62 for opening and closing from the hydraulic pump 10 Second for switching supplied pressure oil
Solenoid valve SV2 and an operation switch S provided in the cab
A pressure switch PS and an accumulator ACC connected to an open / close hydraulic cylinder device 62 and an external pipe, and a relief valve RV.

The opening / closing hydraulic cylinder device 62 is a cylinder 1
A pilot operated check valve PC provided in a pipe connecting the cylinder 1 and the hydraulic pump 10, and first and second check valves CV1, provided in parallel with the pilot operated check valve PC and connected in series with each other. CV2. The pilot operated check valve PC allows the flow of the pressure oil into the bottom chamber 1a of the cylinder 1 and prohibits the flow of the pressure oil from the bottom chamber 1a, but the pressure oil is supplied to the rod chamber 1b of the cylinder 1. Only in such a case, the pressure oil is allowed to flow out of the bottom chamber 1a. The first and second check valves CV1 and CV2 are connected to the bottom chamber 1a of the cylinder 1.
It is configured to allow inflow of pressurized oil to the pump and prohibit outflow of pressurized oil. The accumulator ACC and the pressure switch PS are connected to a pipeline between the first check valve CV1 and the second check valve CV2. Here, the pilot operated check valve PC and the check valves CV1 and CV2 are integrated with the cylinder 1
And a pilot operated check valve P
C, check valves CV1, CV2 and cylinder 1
Are connected to each other by an internal pipe in the hydraulic cylinder device 62 for opening and closing. In addition, the opening and closing hydraulic cylinder device 6
2 is rotated by the driving of the gripping device 34, so that a pipeline for supplying pressure oil from the hydraulic pump 10 to the opening / closing hydraulic cylinder device 62 and a power switch P
The electric wire to be supplied to S is arranged in a swivel joint SJ provided in the turning frame 50.

Next, the operation of the hydraulic circuit of the gripping device according to the present invention will be described. First, a case where the shape steel is gripped by the gripping device 34 will be described. Operation switch SW
1 is switched to the a side and the c side, and the second solenoid valve SV2 is excited to be switched to the g side. In this state, if a certain amount of pressure oil does not act on the pressure switch PS, the pressure switch PS is kept on, so that the first solenoid valve SV1 communicates with the power supply 11 and is excited to be switched to the e side. Thus, the first and second solenoid valves SV
When 1, SV2 is switched, the pressure oil from the hydraulic pump 10 is supplied to the bottom chamber 1a of the cylinder 1 via the pilot operated check valve PC and the first and second check valves CV1, CV2. As a result, the cylinder 1 is extended, the movable claw 54 of the gripper 34 is closed, and the mold steel disposed between the movable claw 54 and the fixed claw 52 is moved to the gripper 3.
4.

On the other hand, the accumulator ACC and the pressure switch PS are connected to the first check valve CV1 and the second check valve CV1.
Is connected to the pipeline between the check valve CV2 and a part of the pressure oil supplied from the hydraulic pump 10 to the accumulator ACC and the pressure switch PS. Therefore, pressurized oil is accumulated in the accumulator ACC. When the mold steel is completely gripped by the movable pawl 54, the cylinder 1 does not extend any more, so the pressure oil in the bottom chamber 1a becomes higher in pressure, and therefore, the pressure oil supplied to the accumulator ACC and the pressure switch PS is reduced. The pressure is also higher. Thereby, while the pressure oil is more accumulated in the accumulator ACC, when the pressure becomes equal to or higher than the predetermined pressure, the pressure switch PS is turned off. When the pressure switch PS is turned off, the power supply 1
1 is disconnected from the first solenoid valve SV1,
The solenoid valve SV1 is demagnetized and switches to the f side. As a result, the hydraulic pump 10 and the tank T communicate with each other, so that no more pressurized oil is supplied to the bottom chamber 1a, and the movable claw 54 is prevented from gripping the mold steel due to excessive gripping pressure.

When the pressure oil is no longer supplied to the bottom chamber 1a as described above, the pilot operated check valve PC and the first and second check valves CV
The outflow of pressure oil from the bottom chamber 1a is prohibited by CV2 and the pressure oil accumulated in the accumulator ACC is supplied to the bottom chamber 1a via the first check valve CV1, so that the cylinder 1 contracts. Instead, the gripping device 34 maintains the state of gripping the section steel with an appropriate gripping pressure. Further, when the gripping pressure decreases, the pressure of the pressure oil supplied to the pressure switch PS decreases, and the pressure switch PS is turned on. Therefore, the first solenoid valve SV1 is excited, and the hydraulic pump 10 transmits the pilot operation check valve. PC and first and second check valves C
Pressure oil is supplied to the bottom chamber 1a via V1 and CV2,
Thereby, the gripping device 34 can also grip the section steel with an appropriate gripping pressure.

In the state where the mold steel is gripped as described above,
When the pipeline between the hydraulic pump 10 and the bottom chamber 1a of the cylinder 1 is broken, pressure oil from the accumulator ACC is supplied to the bottom chamber 1a via the first check valve CV1, and the pilot operated check valve is used. PC and first and second check valves CV1, CV
2 prevents the pressure oil from flowing out of the bottom chamber 1a, so that the cylinder 1 does not contract rapidly, and the gripping device 34 maintains a predetermined gripping force.

On the other hand, when the pipeline between the accumulator ACC and the opening / closing hydraulic cylinder device 62 is broken, the hydraulic oil from the bottom chamber 1a is opened by the pilot operated check valve PC and the first and second check valves CV1 and CV2. Outflow is prohibited and the pressure switch P
Since the pressure of the pressure oil supplied to S is reduced and the pressure switch PS is turned on, the first solenoid valve SV1 is excited, and the pilot operation check valve PC and the first and second check valves are transmitted from the hydraulic pump 10 to the first solenoid valve SV1. CV
1. Since the pressurized oil is supplied to the bottom chamber 1a via the CV 2, the gripping device 34 can continue to grip the shape steel.

In order to release the gripping of the mold steel by the gripping device 34, the operation switch SW1 is switched to the b side and the c side, and the second solenoid valve SV2 is demagnetized and switched to the h side. In this state, if a certain amount of pressure oil does not act on the pressure switch PS, the pressure switch PS is turned on, and the first solenoid valve SV1 is switched to the e side because it is excited in communication with the power supply 11. When the first and second solenoid valves SV1 and SV2 are switched in this manner, the pressure oil from the hydraulic pump 10 is supplied to the rod chamber 1b of the cylinder 1. At the same time, pressure oil is supplied to the pilot port of the pilot operation check valve PC on the hydraulic pump 10 side, so that pressure oil from the bottom chamber 1a of the cylinder 1 is supplied to the pilot operation check valve PC and the second port.
Flows into the tank T through the solenoid valve SV2. Therefore, the cylinder 1 contracts, whereby the movable pawl 54 of the gripping device 34 is opened, and the mold steel disposed between the movable claw 54 and the fixed claw 52 is released from gripping by the gripping device 34.

In the above embodiment, the gripping device provided with two cylinders has been described.
The present invention is not limited to this, and can be applied to a gripping device having one or more cylinders.

In the correspondence between the above embodiment and the claims, the hydraulic pump 10 serves as a hydraulic source, the movable claw 54 and the fixed claw 52 serve as a gripping part, the cylinder 1 serves as a telescopic cylinder, and the second
Electromagnetic valves SV2 constitute the switching valves.

[0026]

According to the erection and dismantling machine of the present invention, even if the pipeline for supplying the pressurized oil to the telescopic cylinder is broken in the state where the mold steel is being grasped, the grasping by the grasping device using the pressurized oil from the accumulator. Power is maintained.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a hydraulic circuit of a gripping device according to the present invention.

FIG. 2 is a side view showing an embodiment of the erection demolition machine to which the hydraulic circuit of the gripping device according to the present invention is applied.

FIG. 3 is a plan view of the construction demolition machine of FIG. 2;

FIG. 4 is a partial cross-sectional side view of the gripping device of the construction demolition machine of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder 1a Bottom chamber 1b Rod chamber 10 Hydraulic pump 11 Power supply 20 Lower traveling body 21 Swivel device 22 Upper revolving body 23 Main body 23C Operating room 25 Mast 25a Inner cylinder 25b Outer cylinder 25c Mast hydraulic cylinder 29 Elevating cylinder 30 Telescopic arm 31 Inner tube 32 Outer tube 34 Gripping device 35 Vertical swing device 36 Left and right swing device 37 Swivel device 41 Hydraulic cylinder for vertical swing 44, 45 Left and right swing cylinder 52 Fixed claw 54 Movable claw 62 Opening and closing cylinder device 75 Link mechanism PC Pilot Operate check valve ACC Accumulator PS Pressure switch SJ Swivel joint SV1, SV2 Solenoid valve SW1 Operation switch RV relief valve

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Seiichi Someno 2-6-2 Otemachi, Chiyoda-ku, Tokyo Hitachi Construction Machinery Co., Ltd. (72) Inventor Akio Iwasaki 2-5-2, Otemachi, Chiyoda-ku, Tokyo Hitachi Construction Machinery Co., Ltd. (72) Inventor Toshiyuki Takasaka 2-6-1, Otemachi, Chiyoda-ku, Tokyo Hitachi Construction Machinery Co., Ltd. (56) References JP-A-3-128894 (JP, A) JP-A-4- 189223 (JP, A) Japanese Utility Model Showa 64-42365 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B66C 1 / 42,13 / 12 B25J 15 / 08,19 / 00

Claims (1)

(57) [Claims] At least one telescopic cylinder which expands and contracts with a hydraulic oil from a hydraulic source to drive a gripping part, a switching valve which switches a direction of hydraulic oil guided to a bottom chamber and a rod chamber of the telescopic cylinder, In a hydraulic circuit of a gripping device having an accumulator for supplying pressure oil to a bottom chamber of the telescopic cylinder, supply of pressure oil to the bottom chamber is permitted, and outflow of pressure oil from the bottom chamber is prohibited, and A pilot operated check valve that permits the outflow of pressurized oil from the bottom chamber only when pressurized oil is supplied to the rod chamber, and a supply of pressurized oil to the bottom chamber, A first and a second check valve provided in parallel with the pilot operated check valve and connected in series with each other to prevent oil outflow; The hydraulic circuit of the gripping device, characterized in that connected between the serial first and second check valve.