KR20030083169A - hydraulic circuit of construction heavy equipment - Google Patents

Abstract

It is to make it easy to change the set pressure and flow path required for the actuator to be replaced according to the working conditions for the heavy equipment main body applied hydraulic and pneumatic system by one-touch operation of the switch. Direction switching for controlling the start, stop and direction change of the actuator 7 provided in the flow path between the actuator 7 driven by the hydraulic oil discharged from (P) and the hydraulic pump 1 and the actuator 7. In the hydraulic circuit for heavy construction equipment, comprising a valve (3) and RCV (1) for controlling the pilot signal pressure discharged from the pilot pump (PP) to switch the direction switching valve (3),

A two-stage relief valve (10) installed in the supply side flow path between the direction switching valve (3) and the actuator (7) to boost the operating pressure supplied to the actuator (7) when the pilot signal pressure is applied; and the direction switching valve (3). And a selector valve (11) installed in the discharge side flow path between the actuator and the actuator (7) and switched when the pilot signal pressure is applied, and the pilot signal pressure from the pilot pump (PP) by a two-stage relief valve (10). ) And a pilot signal pressure supply means for simultaneously applying to the selection valve (11).

Description

Hydraulic circuit of construction heavy equipment with variable set pressure and flow path

The present invention is a construction in which the set pressure and the flow path of the actuator is variably adjusted so as to work by selectively mounting an actuator (referring to a hammer or a cutter) different in operating pressure and flow path for heavy equipment to which a hydraulic and pneumatic system is applied. It relates to a hydraulic circuit for heavy equipment.

More specifically, the present invention relates to a hydraulic circuit for heavy construction equipment that enables the user to easily change a set pressure and a flow path required for driving an actuator to be replaced according to working conditions by one-touch operation of the switch.

1 and 2, the hydraulic circuit of the construction equipment according to the prior art, the hydraulic pump (P) driven by the engine, and the actuator driven by the hydraulic oil discharged from the hydraulic pump (P) (7; hammer or hydraulic cutter), the direction switching valve (3) installed in the flow path between the hydraulic pump (P) and the actuator (7) for controlling the flow direction of the hydraulic oil supplied to the actuator (7), and the direction switching RCV (1) for controlling the pilot signal pressure discharged from the pilot pump (PP) applied to switch the valve (3), and the main relief valve (2) for maintaining the pressure set in the hydraulic circuit.

Therefore, as shown in Fig. 1, when a small hammer is required to be mounted as the operating pressure of the actuator, the hydraulic oil discharged from the hydraulic pump P is switched to the RCV (1) operation ( In the drawing, it is supplied to the cylinder head 8 side of the hammer 7 via the direction switching valve 3 which is switched downward, and is discharged from the cylinder rod 9 side of the hammer 7. The working oil is repeatedly drained to the hydraulic tank (T) through the three-way valve (6) installed in the discharge side flow path of the hammer (7) can be a hammer operation.

At this time, the operating pressure supplied to the cylinder head 8 side of the hammer 7 is maintained to be relatively low pressure than the pressure set in the hydraulic system of the heavy equipment main body by the relief valve 5 installed in the supply side flow path of the hammer 7 Is set.

As shown in Figure 2, when working to replace the hydraulic shear (shear) that requires a high pressure as the operating pressure relative to the hammer, the hydraulic fluid discharged from the hydraulic pump (P) is in the operation of RCV (1) By alternately supplying and discharging to the cylinder head 8 and the cylinder rod 9 side of the hydraulic cutter 7 via the direction switching valve 3 to be switched, it is possible to perform a cutting operation.

At this time, the heavy-duty main body is operated by three-way valves 4 and 6 provided on the supply side and the discharge side flow path of the hydraulic cutter 7 as the working pressure supplied to the cylinder head 8 or the cylinder rod 9 of the hydraulic cutter 7. The high pressure of the hydraulic system is set to be supplied.

However, the above-mentioned hammer or hydraulic cutting machine of the actuator 7 is different from the operating pressure required during operation, and thus, the three-way valves 4 and 6 are selectively provided on the supply side and the discharge side flow path of the actuator 7 during the operation. Since the manual operation must be changed direction, the workability is remarkably inferior.

In addition, when most drivers who do not have professional knowledge on the maintenance of heavy equipment misoperate the three-way valves (4, 6), there is a problem that the hydraulic fluid is lost due to leakage as well as may cause a safety accident.

An object of the present invention is to change the set pressure and the flow path required for the actuator to be selectively replaced according to the working conditions to one-touch operation of the switch during operation, so that the driver can concentrate on the work, thereby greatly improving workability. It is to provide a hydraulic circuit for construction equipment in which a set pressure and the flow path is adjusted.

Another object of the present invention is to provide a hydraulic circuit for heavy equipment for construction to prevent the driver's expert knowledge from changing the set pressure and the flow path required for driving the actuator, to prevent the leakage of hydraulic oil, and to prevent the occurrence of a safety accident. To provide.

1 is a hydraulic circuit diagram of a heavy construction equipment according to the prior art,

2 is another hydraulic circuit diagram of the heavy construction equipment according to the prior art,

3 is a hydraulic circuit diagram of the heavy construction equipment according to an embodiment of the present invention,

4 is an operation of the hydraulic circuit according to another embodiment of the present invention.

* Explanation of symbols used in the main part of the drawing

One; RCV

2; Main relief valve

3; Directional Valve

7; Actuator

8; Cylinder head

9; Cylinder rod

10; 2-stage relief valve

11; Selector valve

12,13; Pilot line

14; Solenoid valve

15; Electric switch

The object of the present invention described above is provided in the oil passage between the hydraulic pump P, the actuator 7 driven by the hydraulic oil discharged from the hydraulic pump P, and the hydraulic pump 1 and the actuator 7. RCV for controlling the pilot signal pressure discharged from the pilot pump PP to switch the direction change valve 3 and the direction change valve 3 to control the start, stop and direction change of the actuator 7. In the hydraulic circuit for heavy construction equipment provided with 1),

A two-stage relief valve (10) installed in the supply side flow path between the direction switching valve (3) and the actuator (7) to boost the operating pressure supplied to the actuator (7) when the pilot signal pressure is applied;

A selection valve 11 installed in the discharge side flow path between the direction switching valve 3 and the actuator 7 and switched when the pilot signal pressure is applied;

A set pressure and flow path, characterized in that it comprises a pilot signal pressure supply means for switching at the time of applying the drive signal and simultaneously applying the pilot signal pressure from the pilot pump PP to the two-stage relief valve 10 and the selection valve 11. Is achieved by providing a hydraulic circuit for the heavy construction equipment which is variable adjusted.

At this time, the above-described pilot signal pressure supply means is switched on and off when the electrical switch 15 and the electrical signal applied from the electrical switch 15 to select the pilot pump (PP) with the two-stage relief valve 10 The solenoid valve 14 which switches to the pilot line 12 and 13 of the valve 11 is provided.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, which are intended to explain in detail to enable those skilled in the art to easily carry out the present invention. It does not mean that the technical spirit and scope of the present invention is limited.

As shown in FIG. 3 and FIG. 4, the present invention is a hydraulic pump (P) connected to the engine to drive, the actuator (7) driven by the hydraulic oil discharged from the hydraulic pump (P), the hydraulic pump The pilot pump (PP) is provided in the flow path between the actuator (1) and the actuator (7) to switch between the direction change valve (3) and the direction change valve (3) for controlling the start, stop, and direction change of the actuator (7). It is applied to the hydraulic circuit for heavy equipment having a RCV (1) for controlling the pilot signal pressure discharged from the), these are the same as shown in Figures 1 and 2, detailed description of the configuration and operation will be omitted, overlapping Reference numerals are the same.

Therefore, the hydraulic circuit for construction equipment in which the set pressure and the flow path of the present invention are variably adjusted is installed in the supply side flow path between the directional control valve 3 and the actuator 7 described above, and the actuator 7 when the pilot signal pressure is applied. Or a hydraulic pressure cutting machine), which is installed in a two-stage relief valve 10 for boosting the operating pressure supplied to the hydraulic cutting machine, and a discharge side flow path between the direction switching valve 3 and the actuator 7 to be switched when the pilot signal pressure is applied. The valve 11, the electric switch 15 electrically on / off, and the electric signal from the electric switch 15 are switched upon application of the pilot signal pressure from the pilot pump PP to the pilot lines 12 and 13. It is provided with a solenoid valve 14 to be simultaneously applied to the two-stage relief valve 10 and the selection valve 11 through.

In the following, the operation of the hydraulic circuit for construction equipment in which the set pressure and the flow path is adjusted according to the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 3, when working with a hammer requiring low pressure as the operating pressure of the actuator, the high pressure hydraulic fluid discharged from the hydraulic pump P is switched to the RCV (1) operation (in the drawing, After passing through the direction switching valve (3) which is switched downward), the hydraulic oil set to low pressure by the two-stage relief valve (10) installed in the supply side flow path of the hammer (7) is the cylinder head ( The hydraulic oil supplied to the 8) side and simultaneously discharged from the cylinder rod 9 side of the hammer 7 passes through the selection valve 11 installed as an initial state to block the discharge side flow path of the hammer 7 to the hydraulic tank. Since the drained to (T) is repeated, the hammer operation can be performed.

On the other hand, as shown in Figure 4, when you want to work by replacing the hydraulic cutting machine that requires a high pressure as the operating pressure relative to the hammer, the electrical signal according to the operation of the above-described electrical switch 15 by the driver As it is applied to one solenoid valve 14 and switched downward in the drawing, the pilot line 12 is routed via the solenoid valve 14 in which a part of the pilot signal pressure discharged from the pilot pump PP is switched. It is applied to the two-stage relief valve 10 through to set the set pressure of the two-stage relief valve 10 to a high pressure, and at the same time a part of the pilot signal pressure is applied to the selection valve 11 through the pilot line 13 to the drawing , Switch upwards.

Therefore, after the high pressure hydraulic fluid discharged from the hydraulic pump P passes through the direction switching valve 3 which is switched upward or downward in the drawing by the pilot signal pressure applied by the RCV 1 operation, The hydraulic oil which maintains the set pressure of the hydraulic system by the step-up and regulated two-stage relief valve 10 is repeatedly supplied and discharged alternately with respect to the cylinder head 8 and the cylinder rod 9 side of the hydraulic cutter 7. As a result, the cutting operation can be performed.

As described above, the hydraulic circuit for heavy equipment construction variable setting pressure and the flow path of the present invention has the following advantages.

It provides convenience to the driver by changing the set pressure and flow path required for the actuator to be selectively replaced according to the working conditions by one-touch operation of the switch during operation, and greatly improves the workability by allowing the driver to concentrate on the work. Can be.

When changing the set pressure and flow path required for the actuator, the operator's expert knowledge is unnecessary, the hydraulic oil is prevented from being lost due to leakage, and the safety accident can be prevented from occurring.

Claims (2)

The hydraulic pump P, the actuator 7 driven by the hydraulic oil discharged from the hydraulic pump P, and the oil passage between the hydraulic pump 1 and the actuator 7 are activated to start the actuator 7. Construction construction comprising a direction switching valve 3 for controlling stop and direction switching and an RCV 1 for controlling pilot signal pressure discharged from the pilot pump PP for switching the direction switching valve 3. In the cost hydraulic circuit: A two-stage relief valve (10) installed in the supply side flow path between the direction switching valve (3) and the actuator (7) to boost the operating pressure supplied to the actuator (7) when a pilot signal pressure is applied; A selection valve 11 installed in the discharge side flow path between the direction switching valve 3 and the actuator 7 and switched when the pilot signal pressure is applied; And And a pilot signal pressure supply means for switching at the time of applying the drive signal and applying the pilot signal pressure from the pilot pump PP to the two-stage relief valve 10 and the selection valve 11 simultaneously. Hydraulic circuit for heavy equipment under construction with variable flow paths. The method of claim 1, wherein the pilot signal pressure supply means; The electric switch 15 which is turned on / off, and is switched when the electric signal from the electric switch 15 is applied to convert the pilot pump PP to the second stage relief valve 10 and the pilot line of the selector valve 11. A hydraulic circuit for heavy equipment for construction, in which a set pressure and a flow path are variably adjusted, comprising a solenoid valve (14) which is connected to the switches 12 and 13).