WO2018034534A1

WO2018034534A1 - Check valve for discharging air, and hydraulic actuator for power plant, having same

Info

Publication number: WO2018034534A1
Application number: PCT/KR2017/009009
Authority: WO
Inventors: 양천규; 김수철; 이승훈; 이동훈; 최용대; 이세호; 송규조; 임훈
Original assignee: 주식회사 에네스지
Priority date: 2016-08-18
Filing date: 2017-08-18
Publication date: 2018-02-22
Also published as: KR101739302B1

Abstract

The present invention relates to a check valve for discharging air which selectively discharges air and a hydraulic fluid, and to a hydraulic actuator for a power plant, having the check valve. The check valve for discharging air according to the present invention comprises: a valve body having an entry and exit passage through which a hydraulic fluid flows in and out, and a discharge passage for discharging, to the outside, air introduced due to the hydraulic fluid which has flowed in through the entry and exit passage and the hydraulic fluid; and a valve spool disposed in the valve body and selectively discharging the air and the hydraulic fluid by reciprocating between a discharging position for discharging the air and the hydraulic fluid in accordance with the hydraulic fluid flowing into and out of the valve body and a blocking position for blocking the discharge of the air and the hydraulic fluid. Accordingly, the spherical valve spool can discharge the air and the hydraulic fluid out of the valve body by moving between the discharging position and the blocking position, thereby preventing damage caused by an explosion of compressed air and enhancing the operational reliability of a piston.

Description

Air release check valve and hydraulic actuator for power plant having same

The present invention relates to an air discharge check valve and a hydraulic actuator for a power plant having the same, and more particularly, to an air discharge check valve for selectively discharging air and hydraulic oil, and a hydraulic actuator for a power plant having the same.

In general, the hydraulic actuator is composed of a cylinder and a piston, and is a device that provides a driving force to the piston in accordance with the hydraulic force of the hydraulic oil drawn in and out of the cylinder. Hydraulic actuators are mainly used in a linear manner to provide a linear movement force of the piston to reciprocate the piston.

Here, the hydraulic actuator is used to open and close the valve connected to the piston, or is widely used in various industries for providing kinetic force to the object connected to the piston. For example, hydraulic actuators are widely used in various fields such as construction machinery field and power plant field.

As described above, the hydraulic actuator reciprocates the piston in accordance with the hydraulic force of the hydraulic oil drawn in and out of the cylinder. On the other hand, when the hydraulic oil is supplied to the cylinder of the hydraulic actuator, the air contained in the hydraulic oil in the pressurized region and the air existing in the cylinder may be compressed and exploded.

However, in the conventional hydraulic actuator, when the air is compressed and exploded in the pressurized zone when the hydraulic oil is supplied to the inside of the cylinder, the sealing member of the piston may be damaged, and thus the hydraulic oil supplied to the pressurized zone is negatively pressured. As there may be a leak, there is a problem that the operating reliability for the hydraulic actuator is lowered.

In particular, the hydraulic actuator for the power plant used in the power plant has a problem that may affect the operation reliability of the turbine when the operation reliability caused by the compression and explosion of air in the pressurized region inside the cylinder as described above.

It is an object of the present invention to provide an air discharge check valve having an improved structure so that air in a pressurized region of a piston supplied with hydraulic oil can be discharged to a negative pressure region, and a hydraulic actuator for a power plant having the same.

In addition, another object of the present invention is to provide a hydraulic actuator for a power plant having an air discharge check valve having an improved structure so that the air in the pressurized region of the piston to which the hydraulic oil is supplied can be discharged to the negative pressure region.

According to the present invention, there is provided a valve body having a withdrawal flow path through which hydraulic oil is drawn in and out, and a discharge body for discharging air and hydraulic oil according to the hydraulic oil drawn into the withdrawal flow path to the outside, and the valve body. A concrete valve disposed inside and reciprocated between a discharge position for discharging air and hydraulic oil and a blocking position for blocking discharge of air and hydraulic oil according to the hydraulic oil drawn in and out of the valve body, and selectively discharging air and hydraulic oil. It is made by an air discharge check valve comprising a spool.

Here, the discharge flow path is formed to face the withdrawal flow path, the first discharge flow path is discharged air and hydraulic oil in the discharge position of the valve spool of the sphere and the discharge of the air and hydraulic oil in the blocking position, and the withdrawal And a second discharge passage formed between the inlet passage and the first discharge passage to guide air and hydraulic oil to the first discharge passage between the discharge position and the shutoff position of the valve spool of the sphere.

The valve body has a first valve body in which the draw flow path is formed, through which hydraulic oil is drawn in and out, and is connected to the first valve body, and the first discharge flow path and the second discharge flow path are formed, and the valve spool of the sphere is formed. It may include a second valve body is formed receiving portion for receiving.

The receiving portion has a shape corresponding to the cross-sectional shape of the valve spool of the sphere, and the second discharge passage is formed in the second valve body in the circumferential direction of the receiving portion is recessed to form the discharge of the valve spool of the sphere Between the position and the blocking position it is possible to guide the air and hydraulic oil to the first discharge passage.

The second discharge passage may be recessed in the second valve body along a reciprocating direction of movement between the discharge position and the blocking position of the valve spool of the sphere.

The air discharge check valve may further include an elastic member disposed in the first discharge flow path of the valve body to provide an elastic force such that the valve spool of the sphere is reciprocated between the discharge position and the blocking position. Can be.

Preferably, the elastic member may be elastically biased to move the valve spool of the sphere from the blocking position to the discharge position.

The draw in and out flow passages are formed in the first valve body and provide a hydraulic power to the valve spool of a sphere when hydraulic oil is drawn in, and the first valve in the circumferential direction of the first draw in and out flow passages. It is formed in the body and the contact area of the sphere with the valve spool may be notched (notch) may include a second draw-in flow passage for guiding the hydraulic oil to the receiving portion when the hydraulic oil is drawn in.

In addition, the air discharge check valve is disposed between the valve spool of the sphere and the elastic member, so that the hydraulic force provided to the valve spool of the sphere when the valve spool of the sphere is moved from the discharge position to the blocking position It may further include an intermediate member for providing to the elastic member and to provide the elastic force of the elastic member to the valve spool of the sphere when the valve spool of the sphere is moved from the blocking position to the discharge position.

In addition, the outer surface of the intermediate member is preferably provided with a lubrication force providing portion for receiving hydraulic oil to provide lubrication between the contact surface of the valve body.

The media member preferably has a lower hardness than the valve spool and the elastic member of the sphere.

On the other hand, according to the present invention, there is provided a piston, a cylinder in which a hydraulic oil receiving space is formed in which the hydraulic oil for receiving and reciprocating the piston is drawn in and out according to the present invention, and the reciprocating movement direction of the piston It is also made by a hydraulic actuator for a power station, characterized in that it comprises an air discharge check valve of the above-described configuration disposed on the piston to selectively discharge the air and hydraulic oil drawn into the cylinder.

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

Effects of the air discharge check valve and the power plant hydraulic actuator having the same according to the present invention are as follows.

First, since the valve spool of the sphere can move between the discharge position and the blocking position to discharge the air and hydraulic oil to the outside of the valve body, it is possible to prevent damage due to the compression and explosion of the air to improve the operating reliability.

Second, between the valve spool and the elastic member of the sphere to arrange the intermediate member having a relatively low hardness compared to the valve spool and the elastic member of the sphere so that when the valve spool of the sphere is reciprocated between the discharge position and the blocking position, the valve of the sphere Damage to the spool and elastic member can be prevented.

Third, by providing a lubricating force providing member for receiving hydraulic oil in the intermediate member to provide lubricating power during the reciprocating movement of the intermediate member, it is possible to improve the operation reliability of the air discharge check valve.

1 is a cross-sectional view of a hydraulic actuator for a power plant according to embodiments of the present invention,

2 is a first operation of the air discharge check valve according to the first embodiment of the present invention,

3 is a cross-sectional view of the III-III line shown in FIG.

4 is a second operation of the air discharge check valve according to the first embodiment of the present invention;

5 is a first operation of the air discharge check valve according to a second embodiment of the present invention,

Figure 6 is a second operation of the air discharge check valve according to a second embodiment of the present invention,

7 is an enlarged view of the region A shown in FIG. 6,

8 is a first operation of the air discharge check valve according to a third embodiment of the present invention,

9 is a second operation of the air discharge check valve according to a third embodiment of the present invention;

FIG. 10 is an enlarged view of region B illustrated in FIG. 9.

Hereinafter, an air discharge check valve and a power plant hydraulic actuator having the same according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Prior to the description, it is noted that the air discharge check valve according to the embodiment of the present invention may be applied to various hydraulic apparatuses such as industrial machinery fields in addition to the hydraulic actuator for power plants described below.

In addition, the air discharge check valves according to the first to the third embodiment of the present invention will be apparent that the same reference numerals denote the same reference numerals.

1 is a cross-sectional view of a hydraulic actuator for a power plant according to embodiments of the present invention.

As shown in FIG. 1, the hydraulic actuator 10 for a power plant according to the embodiments of the present invention includes a piston 100, a cylinder 300, and an air discharge check valve 500. In addition, the hydraulic actuator 10 for the power plant according to the embodiments of the present invention further includes a hydraulic oil storage unit 400.

The piston 100 is connected to a turbine valve, not shown in the present invention. The piston 100 is disposed in the cylinder 300 and is reciprocated according to the hydraulic oil drawn in and out relative to the cylinder 300. The piston 100 divides the inside of the cylinder 300 into a pressurized region in which the hydraulic force is provided by the hydraulic oil and a negative pressure region in which the hydraulic force is not provided. In the embodiments of the present invention described as a single-actuated power plant hydraulic actuator 10 is permanently divided into a pressurized region and a negative pressure region by the piston 100, in the double-actuated power plant hydraulic actuator 10 in the piston 100 As a reference, the pressurized region and the negative pressure region may be alternately substituted.

Cylinder 300 houses piston 100. As described above, the interior of the cylinder 300 is divided into a pressurized region in which the hydraulic force is provided by the piston 100 and a negative pressure region in which the hydraulic force is not provided. Hydraulic oil is drawn in and out in the pressurized region inside the cylinder 300 to provide hydraulic pressure to the piston 100.

An air discharge check valve 500 is disposed on the piston. The air discharge check valve 500 will be described in detail in the first to third embodiments to be described later.

The hydraulic oil storage unit 400 is disposed to store and supply the hydraulic oil drawn in and out of the cylinder 300.

Figure 2 is a first operation of the air discharge check valve according to the first embodiment of the present invention, Figure 3 is a cross-sectional view of the line III-III shown in Figure 2, and Figure 4 according to a first embodiment of the present invention The second operation figure of the air discharge check valve.

As shown in Figures 2 to 4, the air discharge check valve 500 according to the first embodiment of the present invention is the valve body 510, the draw-out flow path 530, the discharge flow path 540 and the valve spool 560. In addition, the air discharge check valve 500 according to the first embodiment of the present invention further includes an elastic member 570.

The valve body 510 is disposed on the piston 100. In the valve body 510, a discharge passage for discharging air and hydraulic oil F according to the withdrawal passage 530 through which the hydraulic oil F is drawn in and out with the hydraulic oil F drawn into the withdrawal passage 530 ( 540 is formed. The valve body 510 includes, as an embodiment of the present invention, a first valve body 512, a second valve body 514, and a receiving part 516. The first valve body 512 has a withdrawal flow passage 530 through which the hydraulic oil F is drawn in and out. The second valve body 514 is connected to the first valve body 512, the second valve body 514 to the hydraulic oil (F) flowing into the withdrawal flow passage 530 formed in the first valve body 512. A discharge passage 540 is formed to discharge to the outside of the valve body 510. The receiving part 516 is formed inside the second valve body 514 to receive the valve spool 560 of the sphere. In detail, the receiving portion 516 forms a space in which the valve spool 560 of the sphere is reciprocated between the discharge position and the blocking position.

The withdrawal passage 530 is formed in the first valve body 512 as described above. The withdrawal flow passage 530 communicates with the pressurized region inside the cylinder 300 to draw in and out the hydraulic oil F drawn into and out of the pressurized region. The hydraulic oil F introduced through the withdrawal flow passage 530 provides hydraulic pressure to the valve spool 560 of the sphere.

The discharge passage 540 guides the hydraulic oil F and the air contained in the hydraulic oil F introduced into the withdrawal passage 530 to the outside of the valve body 510. In addition, the discharge passage 540 guides the air present in the pressurized region of the cylinder 300 together with the hydraulic oil F to the outside of the valve body 510. As an embodiment of the present invention, the discharge passage 540 includes a first discharge passage 542 and a second discharge passage 544.

The first discharge passage 542 is formed to face the withdrawal passage 530 to discharge the air and the hydraulic oil F to the outside of the valve body 510. The first discharge passage 542 discharges air and hydraulic oil F at the discharge position of the valve spool 560 of the sphere, and the air and hydraulic oil F discharged into the first discharge passage 542 is the valve spool of the sphere. If it is located in the blocking position of 560 is blocked.

The second discharge passage 544 is formed between the withdrawal passage 530 and the first discharge passage 542 to remove air and hydraulic oil F between the discharge position and the shutoff position of the valve spool 560 of the sphere. The discharge path 542 is guided. The second discharge passage 544 is recessed in the second valve body 514 along the reciprocating direction of movement between the discharge position and the blocking position of the valve spool 560 of the sphere. In detail, as illustrated in FIG. 3, the second discharge passages 544 are recessed along the circumferential direction of the second valve body 514 and four are disposed at intervals of 90 degrees in one embodiment. That is, the second discharge passage 544 is recessed with respect to the contact surface between the inner wall surface of the second valve body 514 and the valve spool 560 of the sphere so that the valve spool 560 of the sphere moves in the discharge position and the blocking position. When the air and the hydraulic oil (F) is guided to the first discharge passage (542). As an embodiment of the present invention, four second discharge passages 544 are formed at intervals of 90 degrees, but at least two may be formed at equal intervals. For example, the second discharge passages 544 are formed at least two, such that two are formed at 180 degree intervals, three are formed at 120 degree intervals, and five are formed at 75 degree intervals.

Next, the valve spool 560 is disposed inside the valve body 510, and a discharge position and air and hydraulic oil F for discharging air and hydraulic oil according to the hydraulic oil F drawn in and out of the valve body 510. It is reciprocated between the blocking positions to block the discharge of air and selectively discharge the hydraulic oil (F). The valve spool 560 of the present invention has the shape of a sphere. The valve spool 560 of the sphere is accommodated in the second valve body 514, that is, accommodated in the receiving portion 516. The outer surface of the valve spool 560 of the sphere is in contact with the inner wall surface of the second valve body 514. Accordingly, the hydraulic oil F flowing into the withdrawal flow passage 530 provides hydraulic pressure to the lower surface of the valve spool 560, and the air and the hydraulic oil F are formed on the inner wall surface of the second valve body 514 and the concrete. Flows into the second discharge passage 544 formed between the valve spools 560.

The elastic member 570 is disposed in the first discharge passage 542 formed in the valve body 510 to provide an elastic force so that the valve spool 560 of the sphere is reciprocated between the discharge position and the blocking position. Specifically, the elastic member 570 is elastically biased so that the valve spool 560 of the sphere is moved from the blocking position to block the discharge of air and hydraulic oil (F) to the outside of the valve body 510. In detail, the elastic member 570 has a valve spool 560 of the sphere is moved from the discharge position to the blocking position by the hydraulic oil (F) introduced into the withdrawal flow passage 530, the hydraulic oil through the withdrawal flow passage 530 When (F) is discharged, the valve spool 560 of the sphere in the shutoff position is provided to be moved to the discharge position.

With this configuration, the operation of the air discharge check valve 500 according to the first embodiment of the present invention will be described below.

First, when the hydraulic oil F is supplied to the pressurized region inside the cylinder 300, the hydraulic oil is supplied to the withdrawal flow passage 530 of the air discharge check valve 500. The hydraulic oil F supplied to the withdrawal flow passage 530 provides hydraulic pressure to the valve spool 560 of the sphere located at the discharge position.

Then, the valve spool 560 of the sphere is moved from the discharge position to the blocking position by the hydraulic force of the hydraulic oil (F), wherein the air and the hydraulic oil (F) is guided to the second discharge passage 544 to the first discharge passage Discharged to 542. Then, when the valve spool 560 of the sphere is positioned in the blocking position, the air discharged to the first discharge passage 542 and the hydraulic oil (F) is blocked.

Second Embodiment

5 is a first operation of the air discharge check valve according to a second embodiment of the present invention, Figure 6 is a second operation of the air discharge check valve according to a second embodiment of the present invention, and FIG. An enlarged view of area A shown in FIG. 6.

As shown in FIGS. 5 to 7, the air discharge check valve 500 according to the second embodiment of the present invention includes a valve body 510, a draw in and out flow path 530, a discharge flow path 540, and a valve spool. 560, an elastic member 570, and an intermediate member 590.

The valve body 510, the discharge passage 540, the valve spool 560 and the elastic member 570 of the air discharge check valve 500 according to the second embodiment of the present invention are provided in the first embodiment of the present invention. Since the air discharge check valve 500 has been described, detailed description thereof will be omitted below.

The withdrawal channel 530 of the second embodiment of the present invention includes a first withdrawal channel 532 and a second withdrawal channel 534. The first draw-out passage 532 is formed in the first valve body 512 and provides hydraulic pressure to the valve spool 560 of the sphere when the hydraulic oil (F) is drawn in. The second draw-out flow passage 534 is recessed in the first valve body 512 in the circumferential direction of the first draw-in flow passage 532 and the second draw-out flow passage 534 is in contact with the valve spool 560 of the sphere. ), The contact area is notched (N). The second draw-out flow passage 534 guides the hydraulic oil F to the receiving portion 516 when the notch N is processed and the hydraulic oil F is drawn therein. Thus, unlike the first embodiment of the present invention, the second draw-out passage 534 may guide the air and the hydraulic oil F to the second discharge passage 544 more quickly.

The intermediate member 590 is disposed between the valve spool 560 and the elastic member 570 of the sphere. The intermediate member 590 provides the elastic member 570 with hydraulic force provided to the valve spool 560 of the sphere when the valve spool 560 of the sphere is moved from the discharge position to the shut off position. On the other hand, the intermediate member 590 provides an elastic force of the elastic member 570 to the valve spool 560 of the sphere when the valve spool 560 of the sphere is moved from the blocking position to the discharge position. The intermediate member 590 has a lower hardness than the valve spool 560 and the elastic member 570 of the sphere. That is, the intermediate member 590 is provided with a softer material than the valve spool 560 and the elastic member 570 of the sphere. Thus, the intermediate member 590 is disposed between the valve spool 560 and the elastic member 570 of the sphere and made of a relatively soft material, to prevent damage to the valve spool 560 and the elastic member 570 of the sphere. There are advantages to it.

With this configuration, the operation of the air discharge check valve 500 according to the second embodiment of the present invention will be described below.

First, when the hydraulic oil F is supplied to the pressurized region inside the cylinder 300, the hydraulic oil F is supplied to the withdrawal flow passage 530 of the air discharge check valve 500. The hydraulic oil F is supplied to the first draw-in flow passage 532 and the second draw-in flow passage 534, respectively, and the air and the hydraulic oil F flowing into the second draw-in flow passage 534 are the second discharge flow path ( 544). The hydraulic oil F flowing into the first draw-out passage 532 and the second draw-out passage 534 provides hydraulic pressure to the valve spool 560 of the sphere located at the discharge position.

Then, the valve spool 560 of the sphere is moved from the discharge position to the blocking position by the hydraulic force of the hydraulic oil (F), wherein the air and the hydraulic oil (F) is guided to the second discharge passage 544 to the first discharge passage Discharged to 542. Then, when the valve spool 560 of the sphere is positioned in the blocking position, the air discharged to the first discharge passage 542 and the hydraulic oil (F) is blocked. Here, when the valve spool 560 of the sphere is moved between the discharge position and the blocking position, the intermediate member 590 disposed between the valve spool 560 and the elastic member 570 of the sphere is the valve spool 560 of the sphere ) And a material having a lower hardness than the elastic member 570 may prevent damage of the valve spool 560 and the elastic member 570 of the sphere.

Third Embodiment

8 is a first operation of the air discharge check valve according to a third embodiment of the present invention, Figure 9 is a second operation of the air discharge check valve according to a third embodiment of the present invention, and FIG. An enlarged view of region B shown in FIG. 9.

8 to 10, the air discharge check valve 500 according to the third embodiment of the present invention includes a valve body 510, a draw in and out flow path 530, a discharge flow path 540, and a valve spool. 560, an elastic member 570, and an intermediate member 590.

The valve body 510, the discharge passage 540, the valve spool 560 and the elastic member 570 of the air discharge check valve 500 according to the third embodiment of the present invention are provided in the first embodiment of the present invention. Since the air discharge check valve 500 has been described, detailed description thereof will be omitted below. In addition, since the outlet flow path 530 of the air discharge check valve 500 according to the third embodiment of the present invention has been described in the second embodiment of the present invention, a detailed description thereof will be omitted.

The intermediate member 590 of the third embodiment of the present invention, like the intermediate member 590 of the second embodiment of the present invention, is disposed between the valve spool 560 and the elastic member 570 of the sphere. The intermediate member 590 provides the elastic member 570 with hydraulic force provided to the valve spool 560 of the sphere when the valve spool 560 of the sphere is moved from the discharge position to the shut off position. The intermediate member 590 provides the elastic force of the elastic member 570 to the valve spool 560 of the sphere when the valve spool 560 of the sphere is moved from the blocking position to the discharge position. The intermediate member 590 has a lower hardness than the valve spool 560 and the elastic member 570 of the sphere. That is, the intermediate member 590 is provided with a softer material than the valve spool 560 and the elastic member 570 of the sphere.

The intermediate member 590 of the third embodiment of the present invention includes a mediator body 592 and a lubrication force providing unit 594. The intermediate member body 592 is in contact with the inner wall surface of the second valve body 514, unlike the intermediate member 590 of the second embodiment of the present invention. The intermediate member body 592 is in contact with the inner wall surface of the second valve body 514, it can prevent the eccentric movement when the valve spool 560 of the sphere is reciprocated between the discharge position and the blocking position.

Lubricating force providing unit 594 is disposed on the intermediate member body 592 at a predetermined interval. The lubrication force providing unit 594 is provided in plurality in the reciprocating direction of the intermediate member body 592. The lubrication force providing unit 594 receives the hydraulic oil F flowing into the first discharge passage 542. The lubrication force providing unit 594 may receive hydraulic oil F to provide lubrication force between the intermediate member body 592 and the second valve body 514.

With this configuration, the operation of the air discharge check valve 500 according to the third embodiment of the present invention will be described below.

In addition, the intermediate member body 592 is in contact with the inner wall surface of the second valve body 514 to prevent the eccentric movement. The intermediate member body 592 is provided with a lubricating force providing unit 594 for receiving hydraulic oil to provide lubricating force between the second valve body 514 and the intermediate member body 592.

Accordingly, the valve spool of the sphere can be discharged to the outside of the valve body while moving between the discharge position and the blocking position, thereby preventing the damage caused by the compression and explosion of the air can improve the operation reliability of the piston.

In addition, a valve member of the sphere when the valve spool of the sphere is reciprocated between the discharge position and the blocking position by arranging an intermediate member having a relatively lower hardness than the sphere of the sphere and the elastic member between the valve spool and the elastic member of the sphere Damage to the spool and elastic member can be prevented.

In addition, by providing a lubricating force providing member for receiving hydraulic oil in the intermediate member to provide lubricating power during the reciprocating movement of the intermediate member, it is possible to improve the operation reliability of the air discharge check valve.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may be embodied in other specific forms without changing the technical spirit or essential features of the present invention. It will be understood that. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention is shown by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. do.

Claims

A valve body having a withdrawal flow path through which hydraulic oil is drawn in and out, and a discharge flow path for discharging air and hydraulic oil according to the hydraulic oil drawn into the withdrawal flow path to the outside;

It is disposed inside the valve body, reciprocating between the discharge position for discharging air and hydraulic oil and the blocking position for blocking the discharge of air and hydraulic oil in accordance with the hydraulic oil drawn in and out of the valve body to selectively air and hydraulic oil An air discharge check valve comprising a valve spool of a sphere to be discharged.
The method of claim 1,

The discharge passage

A first discharge passage formed opposite to the take-out flow passage, the air and hydraulic oil being discharged at the discharge position of the valve spool of the sphere and the discharge of the air and hydraulic oil blocked at the blocking position;

A second discharge flow path formed between the take-out flow path and the first discharge flow path to guide air and hydraulic oil to the first discharge flow path between the discharge position and the shutoff position of the valve spool of the sphere; Air discharge check valve characterized in that.
The method of claim 2,

The valve body,

A first valve body having the withdrawal flow path through which hydraulic oil is drawn in and out;

And a second valve body connected to the first valve body, wherein the first discharge channel and the second discharge channel are formed, and a receiving part is formed to receive the valve spool of the sphere. valve.
The method of claim 3, wherein

The receiving portion has a shape corresponding to the cross-sectional shape of the valve spool of the sphere,

At least two second discharge passages are formed in the second valve body in the circumferential direction of the receiving portion to guide air and hydraulic oil to the first discharge passage between the discharge position and the shutoff position of the valve spool of a sphere. Air discharge check valve, characterized in that.
The method of claim 4, wherein

And the second discharge passage is recessed in the second valve body in a reciprocating direction between the discharge position and the shutoff position of the valve spool of the sphere.
The method of claim 2,

The air discharge check valve,

An air discharge check valve disposed in the first discharge passage of the valve body, the elastic member providing an elastic force so that the valve spool of the sphere is reciprocated between the discharge position and the blocking position; .
The method of claim 6,

And the elastic member is elastically biased such that the valve spool of the sphere is moved from the blocking position to the discharge position.
The method of claim 3, wherein

The withdrawal flow path

A first drawing flow passage formed in the first valve body and providing hydraulic pressure to the valve spool of a sphere when hydraulic oil is drawn in;

A recess formed in the first valve body in the circumferential direction of the first draw-out flow passage, and a contact area with the valve spool of the sphere is notched to guide the hydraulic oil to the receiving portion when the hydraulic oil is drawn in. An air discharge check valve comprising a draw-out flow path.
The method of claim 6,

The air discharge check valve,

Disposed between the valve spool of the sphere and the elastic member, providing the elastic member with hydraulic force provided to the valve spool of the sphere when the valve spool of the sphere is moved from the discharge position to the shutoff position And an intermediate member for providing an elastic force of the elastic member to the valve spool of the sphere when the valve spool is moved from the blocking position to the discharge position.
The method of claim 9,

A check valve for air discharge, characterized in that the outer surface of the intermediate member is provided with a lubricating force providing portion for receiving hydraulic oil, and provides a lubricating force between the contact surface of the valve body.
The method of claim 9,

The intermediate member has a lower hardness than the valve spool and the elastic member of the sphere air discharge check valve.
A piston;

A cylinder accommodating the piston and having a hydraulic oil accommodating space through which hydraulic oil for reciprocating the piston is drawn out;

And an air discharge check valve of any one of claims 1 to 11 disposed on the piston along a reciprocating direction of the piston to selectively discharge air and hydraulic oil introduced into the cylinder. Hydraulic actuators for power plants.