KR20030051006A - heavy equipment - Google Patents

Abstract

PURPOSE: A hydraulic circuit for selecting multifunction by using a pilot valve is provided to improve convenience and working efficiency and prevent accidents from wrong selection of the valve by changing the function of the heavy equipment conveniently corresponding to work condition with operating the function selection valve and the remote control valve. CONSTITUTION: A hydraulic circuit for selecting multifunction changes the setting pressure by actuating a function selection valve(27) and a pilot valve in applying the electric signal, and modifies the function selectively and easily according to work condition by joining plural hydraulic pumps. The hydraulic circuit includes the function selection valve changing the setting pressure in the hydraulic circuit into high or low pressure by applying pilot signal pressure from a second main pump(21) to a relief valve(25) in applying the electric signal, a selection valve(28) selecting a main line passage of actuating pressure supplied to an actuator(22) according to the pilot signal in switching the function selection valve, and a conflux unit joining the first main pump and the second main pump in operating the remote control valve in applying the electric signal.

Description

Multifunctional selection hydraulic circuit using pilot valve

The present invention uses a pilot valve to prevent the operation of the operation valve to be selected by error due to the operator's carelessness when using the pilot valve to selectively change the function of the work device according to the working conditions of heavy equipment such as excavators, etc. A multifunctional selection hydraulic circuit.

More specifically, by changing the set pressure in the hydraulic circuit to high or low pressure or by joining a plurality of hydraulic pumps by a function selection valve and a pilot valve driving to drive when an electrical signal is applied, the function of the work device is selectively selected according to the working conditions. A multifunctional selection hydraulic circuit using a pilot valve can be easily changed.

As shown in FIG. 1, the heavy equipment according to the prior art includes a first main pump 8 and a second main pump 7, an actuator 9 connected to and driven by the first main pump 8, A direction switching valve (5) installed in a flow path between the first main pump (8) and the actuator (9) to control the start, stop, and direction change of the actuator (9) during the switching; and the second main pump (7); It is provided with a remote control valve (RCV) 4 which is provided in the flow path between the direction switching valves 5, and switches the direction switching valves 5.

Therefore, the pilot signal pressure acts on the left or right end of the directional control valve 5 via the remote control valve 4 by the operation of the remote control valve 4 to switch to the first main pump 8. The operating pressure discharged from the actuator is supplied to and driven by the actuator 9 via the position switching valve 5.

At this time, in order to maximize the working efficiency of the heavy equipment according to the working conditions, the first main pump (by operating the manual stop valve 6 installed in the flow path between the supply port of the second main pump 7 and the directional valve 5) 8) joins the second main pump (7), and operates the manual three-way valve (1) installed in the flow path connecting the large chamber (9a) and the small chamber (9b) of the actuator (9) in the hydraulic circuit The set pressure can be changed to high or low pressure, and the first main pump 8 is operated by operating a manual three-way valve 2 provided in a flow path between the direction switching valve 5 and the small chamber 9b of the actuator 9. It is possible to select the main line flow path to supply the working pressure from the actuator to the actuator (9).

However, as described above, the operator selects the function of the equipment by selectively operating the manual stop valve 6 and the manual three-way valves 1 and 2 according to the working conditions. If the manual operation valve selection is made in error due to the carelessness of the driver, a safety accident occurs.

Accordingly, an object of the present invention is to provide convenience to the driver by easily changing the function of the work device in accordance with the working conditions due to the operation of the function selection valve and the remote control valve to drive when the electrical signal is applied, the operation valve In order to prevent the occurrence of safety accidents due to the error selection of the multifunctional selection hydraulic circuit using a pilot valve.

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

Figure 3 is a multi-function selection hydraulic circuit using a pilot valve according to an embodiment of the present invention.

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

20; First main pump

21; 2nd main pump

22; Actuator

22a; Large Chamber

22b; Small chamber

23; Directional Valve

24; Remote control valve

25,26; Relief valve

27; Function selection valve

28; Selector valve

29; Joining Solenoid Valve

30; Confluence valve

The object of the present invention described above is installed in the flow path between the first main pump and the second main pump, the actuator connected to the first main pump, the first main pump and the actuator to start, stop and change the direction of the actuator. Hydraulic circuit of heavy equipment including a directional control valve to control, a remote control valve to control the pilot signal pressure applied to the directional control valve, a relief valve installed in the flow path between the directional control valve and the actuator to maintain the set pressure in the hydraulic circuit In the present invention, a function selection valve which is switched when an electrical signal is applied and applies a pilot signal pressure to the relief valve to change the set pressure in the hydraulic circuit to high or low pressure, and is driven by a pilot signal applied when switching the function selection valve to the actuator. Selection valve for selecting main line flow path of supplied working pressure and switching when electric signal is applied It is achieved by providing a multi-function selection hydraulic circuit using a pilot valve, characterized in that it comprises a joining means for joining the pump when operating the remote control valve.

According to a preferred embodiment, the above-mentioned confluence means comprises: a confluence valve installed between the second main pump and the inflow side port of the directional control valve, and a pilot signal pressure that is switched when an electric signal is applied and passes through the remote control valve. And a joining solenoid valve for supplying to the second main pump to join the first main pump.

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

As shown in FIG. 2, the multifunctional selection hydraulic circuit using a pilot valve according to an embodiment of the present invention includes a first main pump 20, a second main pump 21, and a first main pump 20. An actuator 22 connected to and driven in the flow path between the actuator 22 and the first main pump 20 and the actuator 22 to control the start, stop, and direction change of the actuator 22; , A remote control valve 24 for controlling the pilot signal pressure applied to the direction switching valve 23, a relief valve installed in a flow path between the direction switching valve 23 and the actuator 22 to maintain a set pressure in the hydraulic circuit. Applied to the hydraulic circuit of the heavy equipment having a 25, these are to be applied substantially the same as shown in Figure 1, so the detailed description of their configuration and operation will be omitted below, overlapping reference numerals are the same Make a note of the notation.

Therefore, according to a preferred embodiment of the present invention, the function selection valve 27 for switching when the electrical signal is applied to apply the pilot signal pressure to the relief valve 25 to change the set pressure in the hydraulic circuit to high or low pressure, and function A selection valve 28 which is driven by a pilot signal associated with operation of the selection valve 27 to select a main line flow path of the operating pressure supplied to the actuator 22, and is switched when an electrical signal is applied to operate the remote control valve 24; And joining means for joining the second main pump 21 to the first main pump 20.

At this time, the merging valve 30 is installed between the second main pump 21 and the inlet side port of the direction switching valve 23 by the merging means described above, and is switched when the electric signal is applied to the remote control valve 24. And a joining solenoid valve 29 for supplying the pilot signal pressure via the to the joining valve 30 to join the second main pump 21 to the first main pump 20.

Hereinafter, the operation of the multifunctional selection hydraulic circuit using the pilot valve according to the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 2, the above-described function selection valve 27 and the remote control valve 24 may be operated to selectively change a function of a corresponding work device according to a working condition.

When the above-described function selection valve 27 is switched left or right by an electrical signal applied from a controller not shown by the driver, the pilot two-stage relief valve 25 may have the aforementioned pilot signal pressure a or b. As applied to the port of the, the set pressure in the hydraulic circuit will be able to select high pressure or low pressure.

At the same time, the pilot signal pressure (a or b) via the switched position selector valve 27 is applied to the valve spring 28a opposite side port of the selector valve 28 described above and positioned upward in the drawing. By switching, the main line flow path of the hydraulic circuit can be selected to the tank side or the direction switching valve 23 side.

At this time, the remote control valve 24 is operated by the driver so that the pilot signal pressure is applied to the function selection valve 27, the shuttle valve 31 and the remote control valve 24 provided in the inflow side flow path of the remote control valve 24. In the case where the direction switching valve 23 is switched in the right direction (B direction) on the drawing via the actuator, the operating pressure discharged from the first main pump 20 passes through the direction switching valve 23 in which the actuator is switched. It is supplied to the large chamber 22a of 22 and driven.

At this time, the hydraulic oil returned from the small chamber 22b of the actuator 22 described above is returned to the tank via the selection valve 28 or returned to the direction switching valve 23.

On the other hand, when the pilot signal pressure switches the direction switching valve 23 to the left direction (A direction) in the drawing due to the above-described operation of the remote control valve 24, the pilot signal pressure is discharged from the first main pump 20. The operating pressure is supplied to the small chamber 22b of the actuator 22 via the selection valve 28 and then driven via the direction switching valve 23 in which the operating pressure is switched.

At this time, the hydraulic oil returned from the large chamber 22a of the actuator 22 described above is returned to the tank via the direction switching valve 23.

On the other hand, when the pilot signal pressure a or b is not applied to the selection valve 28 described above, the hydraulic oil discharged from the first main pump 20 described above is drained to the tank side via the relief valve 26. By doing so, it is possible to protect the hydraulic circuit by preventing unnecessary hydraulic oil from being supplied to the actuator 22.

In addition, when the electrical signal from the controller not shown is applied to the above-mentioned solenoid valve 29 to switch downward in the drawing, the shuttle valve 32 provided between the discharge side flow paths of the remote control valve 24 is removed. The second main pump 21 with respect to the first main pump 20 by switching the merging valve 30 to the right in the drawing via the merging solenoid valve 29 having the pilot signal pressure passed therethrough. ) Can be joined.

As mentioned above, according to a preferable embodiment, it has the following advantages.

Functions that operate when electric signal is applied The operation of selection valve and remote control valve makes it easy to change the function of the corresponding work device of heavy equipment according to the working conditions, providing the operator with convenience and greatly improving workability. Therefore, it is possible to prevent the occurrence of safety accidents caused by the error selection of the corresponding operation valve.

Claims (2)

An actuator connected to the first main drive, a direction change valve installed in a flow path between the first main pump and the actuator to control the start, stop, and direction change of the actuator, and a pilot signal pressure applied to the direction change valve. In the hydraulic circuit of a heavy equipment having a remote control valve, a relief valve installed in the flow path between the directional control valve and the actuator to maintain a set pressure: A function selection valve that is switched upon application of an electrical signal to apply a pilot signal pressure from the second main pump to the relief valve to change the set pressure in the hydraulic circuit to high or low pressure; A selection valve which is driven by a pilot signal applied when the function selection valve is switched to select a main line channel of an operating pressure supplied to the actuator; And A multi-function selection hydraulic circuit using a pilot valve, characterized in that it comprises a joining means for switching when the electrical signal is applied to join the other pump to the existing pump when operating the remote control valve. According to claim 1, wherein said joining means; A confluence valve installed between the inflow side ports of the directional valve and an electric signal applied to switch the converging valve through the remote control valve to supply the converging valve to the main pump Multifunctional selection hydraulic circuit using a pilot valve, characterized in that the solenoid valve for.