KR20140048376A

KR20140048376A - Poppet type bypass-cut valve

Info

Publication number: KR20140048376A
Application number: KR1020120112790A
Authority: KR
Inventors: 박형준; 이상우; 장달식
Original assignee: 두산인프라코어 주식회사
Priority date: 2012-10-11
Filing date: 2012-10-11
Publication date: 2014-04-24

Abstract

The present invention relates to a poppet type bypass-cut valve. The poppet type bypass-cut valve according to an embodiment of the present invention comprises: a first body (110) which includes a first chamber (112) having a first inner diameter (d1), an inflow port (114) and an outflow port (115) respectively formed at both sides of the first chamber (112), and a drain port (116) formed at an end portion of the opposite side of the first chamber (112); a second body (120) which is joined to the first chamber (112) of the first body (110) and has a second chamber (122) having a second inner diameter (d2) of the same size as the first inner diameter (d1); a poppet (130) accommodated in the first chamber (112) to cut off the inflow port (114) from the outflow port (115) when the poppet comes into contact with an end portion of the second chamber (122); a compression spring (140) which is accommodated in the first chamber (112) and applies a restoring force to push the poppet (130) toward the second body (120); a first orifice (150) disposed at the center of the poppet (130) to reduce a flow rate; and a second orifice (160) disposed between the first chamber (112) and the drain port (116) inside the first body (110) to reduce a flow rate.

Description

Poppet type Bypass-cut Valve

The present invention relates to a poppet-type bypass cut valve, and more particularly, to a poppet-type bypass cut valve for controlling opening and closing of a center bypass line configured in a hydraulic circuit of a construction machine under specific conditions.

In general, the bypass cut valve is configured in the hydraulic circuit of the construction machine to receive an external signal as an input and operate the spool to close or open the center bypass line. . Hereinafter, the bypass cut valve will be abbreviated as 'BC valve'.

The hydraulic circuit of the construction machine will be described with reference to FIG. 1.

1 is an exemplary view of a hydraulic circuit for excavator control.

As shown in FIG. 1, hydraulic oil is discharged from the first and second hydraulic pumps 11 and 12. The hydraulic oil discharged from the first and second hydraulic pumps 11 and 12, respectively, is provided to the main control valve MCV, and the hydraulic oil is distributed from the main control valve MCV to the desired actuator.

The main control valve MCV includes the first and second center bypass lines 21 and 31, the first and second parallel lines 22 and 32, the first and second confluence lines 23 and 33, and the various firsts. , Second group control valve units 41, 42, 51, 52 are arranged.

The first hydraulic oil provided from the first hydraulic pump 11 is discharged to the drain line 70 via the first center bypass line 21 and through the first bypass cut valve 61.

Similarly, the second hydraulic oil provided from the second hydraulic pump 12 passes through the second center bypass line 31 and is discharged to the drain line 70 through the second bypass cut valve 62.

The first group control valves 41 and 42 are disposed in the first bypass line 21 described above, and the second group control valves 51 and 52 are disposed in the second bypass line 31.

That is, the 1st hydraulic pump 11 is in charge of the hydraulic fluid flow volume to the 1st group control valve 41 and 42, and the 2nd hydraulic pump 12 is responsible for the 2nd group control valve 51 and 52. FIG.

When operating a construction machine, for example, when operating an excavator at least two actuators at the same time, at this time, a phenomenon that the flow rate of the hydraulic oil provided to the actuator may be insufficient, thereby causing a problem of deterioration of workability.

More specifically, for example, when performing a combined operation in any one of the first group control valves 41 and 42 and the second group control valves 51 and 52, for example, the second hydraulic pump 12 In order to compensate for the insufficient flow rate discharged from), the first bypass cut valve 61 of the center bypass line 21 of the other first hydraulic pump 11 is closed, whereby the first confluence line 23 is closed. It joins to the discharge flow volume of the other 2nd hydraulic pump 12 via. That is, the plurality of actuators provided with the hydraulic oil in the second bypass line 31 can smoothly perform a desired operation when performing a combined operation.

Conventional first and second bypass cut valves 61 and 62 will be described with reference to FIG. 2. 2 is a cross-sectional view illustrating a BC valve in the main control valve MCV as an exemplary view for explaining a conventional BC valve.

As shown in FIG. 2, various valves are provided in the main control valve MCV. The valve consists of a combination of flow path, spool and spring. That is, the first and second bypass cut valves 61 and 62 also include a spool 63 and a spring 64, the spring 64 is protected by the spool cap 65, and the spool cap 65 is It is fixedly installed on the main control valve (MCV). In addition, a relief valve unit 80 is provided at one side of the bypass cut valve, and the relief valve unit 80 allows the hydraulic oil of excessive pressure to be discharged when a pressure higher than the set pressure is formed.

The spool 63 is linearly moved in the spool housing 66 formed in the main control valve MCV, and precise processing is required as the flow direction and the flow rate of the hydraulic oil change according to the position of the spool 63.

The spring 64 is provided with a bolt 67, and the degree to which the spool 63 responds to the pressure of the hydraulic oil varies depending on the degree of tightening the bolt 67. That is, a pressure adjustment process (tuning) is performed to move the spool 63 at a desired pressure.

As described above, the conventional first and second bypass cut valves 61 and 62 are configured as BC valves in the form of spools, and between the spool 63 and the notch and the stage for determining the switching timing of the valve. Tuning should be performed to change the distance. That is, each time the adjustment process is performed, the spool cap 65 is removed, and the spool 63 is pulled out to process the notch shape and the distance between the steps.

On the other hand, the space required for mounting the spool type BC valve to the main control valve (MCV) is large, and the clearance between the spool 63 and the spool housing 66 for smooth operation of the spool 63. Since this exists, there is a problem that internal leakage occurs.

On the other hand, in order to mount a spool BC valve, a spool housing is required and a space to be occupied by the spool cap 65 is required, which makes it difficult to manufacture a mold of a casting material. Furthermore, there is a problem that the manufacturing cost increases due to an increase in the defective rate of the material.

Accordingly, the technical problem to be achieved by the present invention is to compensate for the problems of the spool type and to reduce the size relative to the conventional spool type bypass cut valve, so that it is provided in the main control valve MCV. The objective is to provide a bypass cut valve in the form of a poppet that can be connected to the port where the fitted Foot Relief Valve was mounted.

The present invention has been made in view of the above problems, and it is an object of the present invention to at least partially solve the problems in the conventional arts. There will be.

In order to achieve the above technical problem, a poppet-type bypass cut valve according to the present invention includes a first chamber 112 having a first inner diameter d1, and is formed at both sides of the first chamber 112, respectively. An inlet port 114 and an outlet port 115, and a first body 110 having a drain port 116 formed at an opposite end of the first chamber 112; A second body (120) fastened from the first body (110) to the first chamber (112) and having a second chamber (122) having a second inner diameter (d2) having the same size as the first inner diameter (d1); 120); A poppet (130) for disconnecting the inlet port (114) and the outlet port (115) when received in the first chamber (112) and in close contact with an end of the second chamber (122); A compression spring (140) accommodated in the first chamfer (112) and acting a restoring force to push the poppet (130) toward the second body (120); A first orifice 150 for reducing the flow rate provided at the center of the poppet 130; And a second orifice 160 disposed between the first chamber 112 and the drain port 116 in the first body 110 to reduce the flow rate.

In addition, in the poppet-type bypass cut valve according to the present invention, a tapered inner circumferential surface 124 is formed at an end of the second chamber 122 toward the poppet 130, and the second chamber 122 is formed. A tapered outer circumferential surface 132 is formed at an end of the facing poppet 130, and when the poppet 130 is in close contact with the second body 120, the tapered inner circumferential surface 124 and the tapered outer circumferential surface 132 are in close contact with each other. To close the center bypass line.

In addition, in the poppet-type bypass cut valve according to the present invention, the male screw 118 is formed on the outer circumferential surface of the first body 110, and the O-ring 126 is disposed on the outer circumferential surface of the second body 120. It may be.

The details of other embodiments are included in the detailed description and drawings.

Poppet-type bypass cut valve according to the present invention made as described above, because the adjustment (tuning) process is very convenient, in order to tune the BC valve, only the inner diameter size of the orifice needs to be changed so that the spool type The adjustment process is much more convenient than the valve. In particular, the conventional spool type bypass cut valve does not need to process the spool notch and the step distance, and it is very convenient because the switching time can be secured only by changing the size of the orifice. .

In addition, the poppet-type bypass cut valve according to the present invention is very advantageous in oil leakage management, and since the center bypass line is opened and closed in the poppet form, the working oil is moved inside without leaking to the outside. Internal leakage prevention effect is better than spool type valve.

In addition, the poppet-type bypass cut valve according to the present invention can be manufactured in a compact size, and the size thereof is comparable to that of the foot relief valve, so that the BC valve of the conventional spool type The smaller size can be provided in about half the size.

In addition, the poppet-type bypass cut valve according to the present invention is advantageous in terms of cost and handling convenience, and includes a port for installing a foot relief valve in the main control valve MCV. The foot relief valve installed in this case can be removed and a bypass cut valve of the poppet type according to the invention can be fitted. That is, the mounting position of the bypass cut valve can be secured in a single process, so that the mold of the casting material can be relatively simple, thereby lowering the processing cost and increasing handling convenience.

In addition, the poppet-type bypass cut valve according to the present invention may be advantageous in the utilization of the hydraulic system, and as a single machining of the mounting position of the bypass cut valve is secured, the conventional control valve (MCV) used in the related art is secured. By replacing the existing foot relief valve with the bypass cut valve according to the present invention it is possible to respond to the new hydraulic system.

1 is an exemplary view of a hydraulic circuit for excavator control.
2 is a cross-sectional view illustrating a bypass cut valve in a main control valve as an exemplary view for explaining a conventional bypass cut valve.
3 and 4 are views for explaining the bypass cut valve of the poppet type according to an embodiment of the present invention, Figure 3 is a poppet is closed state, Figure 4 is a poppet open state.
5 is a hydraulic circuit diagram illustrating a bypass cut valve of a poppet type according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and how to accomplish them, will become apparent by reference to the embodiments described in detail below with reference to the accompanying drawings.

Like reference numerals refer to like elements throughout the specification, like reference numerals are used to refer to like elements throughout the related art, and a description thereof will be omitted.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

One of the systems for controlling hydraulic circuits in construction machinery is the negative cone system. The negative cone system determines the discharge flow rate of the pump by the pressure of the bypass line. The pressure in the bypass line is the part of the loss that does not actually work (use hydraulic oil for the purpose of moving the machine). A new hydraulic circuit control system has been developed to improve fuel efficiency by controlling the discharge flow rate of the hydraulic pump by the software (S / W) command without using a bypass line as an advanced form.

As described above, bypass lines are not used as hardware (H / W) in the new hydraulic circuit control system, and in some cases bypass bypass valves are used with the intention of opening the bypass lines. Sometimes.

Hereinafter, a bypass cut valve of a poppet type according to an embodiment of the present invention will be described with reference to FIGS. 3 to 5.

3 and 4 are diagrams for explaining the bypass cut valve of the poppet type according to an embodiment of the present invention, Figure 3 is a poppet is closed, Figure 4 is a poppet is open. 5 is a hydraulic circuit diagram illustrating a bypass cut valve having a poppet according to an embodiment of the present invention.

As shown in FIGS. 3 and 4, in the poppet-type bypass cut valve 100 according to the exemplary embodiment, the first body 110 and the second body 120 are combined, and the first body. Poppet 130 is provided inside the 110. The first chamber 112 is formed in the first body 110, and the compression spring 140 is provided in the first chamber 112. Compression spring 140 is a restoring force is applied in the direction in which the above-mentioned poppet 130 is subjected to a force pushed by the restoring force of the compression spring 140.

In addition, the first orifice 150 is provided in the center of the poppet 130, and the second orifice 160 is provided in the middle of the first body 110.

In addition, the inlet port 114 and the outlet port 115 are formed on both side surfaces of the first body 110, respectively, and the drain port 116 behind the second orifice 160 described above in the first body 110. Is formed. A male screw 118 is formed on an outer circumferential surface of the first body 110, and the male screw 118 may be used for fastening when installed in the main control valve MCV.

The second body 120 has a second chamber 122 formed at the inner center thereof, and a tapered inner circumferential surface 124 is formed at an end portion of the second body 122 coupled to the first body 110, and an O-ring 126 is formed on the outer circumferential surface thereof. Is provided. The O-ring 126 prevents leakage when the bypass cut valve 100 is installed in the main control valve MCV.

Meanwhile, sizes of the first inner diameter d1 of the first chamber 112 and the second inner diameter d2 of the second chamber 122 are the same.

In addition, a tapered outer circumferential surface 132 is formed at an end of the poppet 130, and the tapered outer circumferential surface 132 is in close contact with the tapered inner circumferential surface 124 described above.

Hereinafter, the operation of the poppet-type bypass cut valve 100 according to an embodiment of the present invention configured as described above will be described.

As shown in FIG. 5, high pressure is applied to the first chamber 122, the inlet port 114, and the first orifice 150 from the main control valve MCV. A separate sub valve unit 200 may be added to the outside of the drain port 116, and the sub valve unit 200 is opened and closed by a command applied from a control unit of the hydraulic system.

When there is no input of a signal from the outside, the poppet 130 remains closed. More specifically, the hydraulic oil flow rate discharged from the hydraulic pump flows into the first and second chambers 112 and 122 through the first orifice 150. On the other hand, by the restoring force of the compression spring 140, the poppet 130 is kept in a pushed state.

The poppet 130 is a state in which the tapered inner circumferential surface 124 and the tapered outer circumferential surface 132 are in close contact with each other, and the inlet port 114 and the outlet port 115 are disconnected and closed.

In addition, since there is no command input from the outside, since the sub valve unit 200 is in a closed state, a pressure difference is not formed at the front end and the rear end of the second orifice 160, and the flow of the flow rate through the second orifice 160 is There will be no.

In addition, since the first and second inner diameters d1 and d2 of the first and second chambers 112 and 122 are the same, the poppet 130 has the compression spring 140 because there is no influence of the force due to hydraulic pressure by the same area. The closed state is maintained by the restoring force of.

In detail, since the first and second inner diameters d1 and d2 of the first and second chambers 112 and 122 are the same, a force pushing the poppet 130 in the direction to open due to the discharge pressure of the hydraulic pump ( The force Fp2 for pushing the Fp1) and the poppet 130 to close is equal. On the other hand, as described above, both forces Fp1 and Fp2 by hydraulic pressure cancel each other, and only the force Fs by the compression spring 140 affects the poppet 130, so that the poppet 130 is pushed out. Will be. That is, the center bypass line is closed by disconnecting the inflow port 114 and the outflow port 115.

When there is an input of a signal from the outside, the poppet 130 remains open. More specifically, when a command is input from the outside, that is, when the sub-valve unit 200 is opened, a low pressure is formed at the drain port 116 and thus a pressure difference is formed at the front end and the rear end of the second orifice 160. do. In addition, a pressure difference occurs between the first chamber 112 and the second chamber 122. If the pressure difference is greater than the restoring force of the compression spring 140, the poppet 130 is pushed open and the flow rate discharged from the hydraulic pump is discharged to the tank. In other words, a pressure difference occurs between the front end and the rear end of the second orifice 160 so that the hydraulic oil filled in the space of the first chamber 112 exits through the second orifice 160. Thereafter, a difference in oil pressure acting on the first chamber 112 and the second chamber 122 occurs. At this time, the force Fp1 pushing the poppet 130 in the direction to open is greater than the force Fp2 pushing the poppet 130 in the direction to close.

Meanwhile, the force Fp1 pushing the poppet 130 in the direction to open is greater than the sum of the force Fp2 pushing the poppet 130 in the direction to close and the restoring force Fs of the compression spring 140. When the poppet 130 is moved, there is a gap between the tapered inner circumferential surface 124 and the tapered outer circumferential surface 132, whereby the inlet port 114 and the outlet port 115 are opened to open the center bypass line. It becomes a state.

Poppet-type bypass cut valve according to an embodiment of the present invention made as described above, because the adjustment (tuning) process is very convenient, in order to tune the BC valve only needs to change the inner diameter size of the orifice spool ( The adjustment process is much more convenient than the spool type valve. In particular, the conventional spool type bypass cut valve does not need to process the spool notch and the distance between steps. There is a convenient advantage.

In addition, the poppet-type bypass cut valve 100 according to an embodiment of the present invention is very advantageous in oil leakage management, and the center bypass line is opened and closed in a poppet type, so that the working oil is moved to the outside. Because it moves inside without leaking, it has better internal leakage prevention effect than spool valve.

In addition, the poppet-type bypass cut valve 100 according to an embodiment of the present invention may be manufactured in a compact size, and thus the size thereof is comparable to that of a foot relief valve. It is possible to provide approximately half the size of the conventional BC valve of the spool type.

In addition, the poppet-type bypass cut valve 100 according to an embodiment of the present invention is advantageous in terms of cost and handling convenience, and for installing a foot relief valve on the main control valve MCV. If a port is present, the installed foot relief valve can be removed and a bypass cut valve of the poppet type according to the invention can be fitted. In detail, the male screw 118 can be fastened and mounted where the foot relief valve 80 is installed, and the O-ring 126 is prevented from leaking inside.

That is, the mounting position of the bypass cut valve can be secured in a single process, so that the mold of the casting material can be relatively simple, thereby lowering the processing cost and increasing handling convenience.

In addition, the poppet-type bypass cut valve 100 according to an embodiment of the present invention may be advantageous in the utilization of the hydraulic system, and as the single machining of the mounting position of the bypass cut valve is secured, it has been conventionally used. By replacing the existing foot relief valve with the bypass cut valve according to the present invention in the main control valve (MCV) it is possible to respond to the new hydraulic system.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. will be.

Therefore, it should be understood that the above-described embodiments are to be considered in all respects as illustrative and not restrictive, and the scope of the present invention is indicated by the appended claims. The scope of the claims and their equivalents It is to be understood that all changes or modifications that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

The poppet type bypass cut valve according to the present invention may be installed in the main control valve and used to control the opening and closing of the center bypass line under specific conditions.

11, 12: 1st, 2nd hydraulic pump 21, 31: 1st, 2nd center bypass line
22, 32: first and second parallel lines 23, 33: first and second confluence lines
41, 42: first group control valve unit 51, 52: second group control valve unit
61, 62: first and second bypass cut valve 70: drain line
80: relief valve unit
100: bypass cut valve 110, 120: first, second body
112, 122: first and second chambers 114: inlet ports
115: outlet port 116: drain port
124: tapered inner circumference
130: poppet 132: tapered outer surface
140: compression spring 150, 160: first and second orifices
200: sub valve unit

Claims

A first chamber 112 having a first inner diameter d1 is formed, and an inlet port 114 and an outlet port 115 are formed at both sides of the first chamber 112, respectively, and the first chamber ( A first body 110 having a drain port 116 formed at an opposite end of the 112;
A second body (120) fastened from the first body (110) to the first chamber (112) and having a second chamber (122) having a second inner diameter (d2) having the same size as the first inner diameter (d1); 120);
A poppet (130) for disconnecting the inlet port (114) and the outlet port (115) when received in the first chamber (112) and in close contact with an end of the second chamber (122);
A compression spring (140) accommodated in the first chamfer (112) and acting a restoring force to push the poppet (130) toward the second body (120);
A first orifice 150 for reducing the flow rate provided at the center of the poppet 130; And
A second orifice (160) provided between the first chamber (112) and the drain port (116) in the first body (110) to reduce the flow rate;
Poppet-type bypass cut valve comprising a.

The method of claim 1,
A tapered inner circumferential surface 124 is formed at the end of the second chamber 122 on the side facing the poppet 130,
A tapered outer circumferential surface 132 is formed at an end portion of the poppet 130 toward the second chamber 122,
When the poppet 130 is in close contact with the second body 120, the tapered inner circumferential surface 124 and the tapered outer circumferential surface 132 are in close contact with each other to close the center bypass line.
Poppet-type bypass cut valve characterized in that.

The method of claim 1,
A poppet-type bypass cut valve, characterized in that a male screw 118 is formed on the outer circumferential surface of the first body 110 and an O-ring 126 is disposed on the outer circumferential surface of the second body 120.