JP2014190523A - Check valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a check valve.SOLUTION: A check valve comprises: a housing 3 that has a fluid passage 4 communicated with a primary side and a secondary side, and in the fluid passage 4 of which a check valve seat 6 is formed; a check valve body 5 that has a relief flow passage 23 communicated with the primary side from the secondary side, and that seats on the check valve seat 6 and can close and open the fluid passage 4, in which a relief valve seat 25 is formed on a primary side end of the relief flow passage 23; a first energization member interposed between the check valve body 5 and the housing 3 and energizing the check valve body 5 in a direction for seating on the check valve seat 6; a relief valve body 26 that is arranged outside the check valve body 5, seats on the relief valve seat 25, and can close and open the relief flow passage 23; and a second energization member for energizing the relief valve body 26 in a direction for seating on the relief valve seat 25.

Description

  The present invention relates to a check valve, and more particularly to a valve that can mitigate an abnormal pressure increase on the secondary side.

  For example, a check valve is often incorporated in the faucet used in a water heater or the like, or in a water supply pipe or hot water pipe connected to the faucet. In addition to the function of preventing the back flow of fluid, this check valve has a function that prevents the check valve itself and the secondary valve when abnormal pressure increases due to water hammer or fluid volume expansion on the secondary side of the check valve. In order to protect various parts arranged in the flow path on the side, those having a pressure relaxation function are also known. The following patent document 1 is mentioned as a structure provided with such a pressure relaxation function.

  In this device, a check valve body is provided inside a housing having a check valve seat, and the check valve body is adapted to receive a biasing force by a first spring, and is seated on the check valve seat. Therefore, backflow is prevented. An escape passage is formed in the check valve body, and a relief valve body for opening and closing the passage is incorporated in the escape passage. An urging force by the second spring acts on the relief valve body, and it is not released to the extent that normal reverse pressure (pressure from the secondary side to the primary side) acts, but an abnormal pressure exceeding this Is configured to open and release the pressure to the primary side.

JP 2010-96298 A

  However, in the above, since the relief valve body is formed inside the check valve body, the check valve body itself is enlarged. Then, during normal water flow, the space between the check valve body and the housing becomes a fluid passage, but it is difficult to secure a cross-sectional area of the fluid passage, and the pressure loss during normal use increases. there were.

  The present invention has been completed based on the above-described circumstances, and it is an object of the present invention to reduce the normal pressure loss as much as possible in a check valve having a function of alleviating an abnormal pressure increase on the secondary side. To do.

  The check valve of the present invention has a check valve seat formed in a fluid passage that leads to a primary side and a secondary side, and a relief passage that leads from the secondary side to the primary side, and the primary side of this relief passage. A relief valve seat is formed at the end, and a check valve body that can be seated on the check valve seat to close and open the fluid passage is attached to the check valve body in a direction to be seated on the check valve seat. A first urging member that is energized, a relief valve element that is disposed outside the check valve body and seats on the relief valve seat to close and open the relief flow path, and seats on the relief valve seat with respect to the relief valve body And a second urging member for urging in the direction of movement.

  According to the present invention, the relief valve body that opens and closes the relief flow path formed in the check valve body is disposed outside the check valve body. By doing so, it is not necessary to secure a space for incorporating the escape valve body in the check valve body, and thus the check valve body can be reduced in size. Along with this, it is possible to secure a wide cross-sectional area of the fluid passage held on the outer peripheral side of the check valve body, and therefore it is possible to reduce the pressure loss of the fluid during normal times. It also contributes to reducing the size of the check valve.

Sectional drawing which shows the state in which the non-return valve body is seated on the non-return valve seat Sectional view showing normal water flow Sectional drawing which shows the valve opening state of a relief valve body AA line sectional view of FIG. BB line sectional view

A preferred embodiment of the present invention will be described.
(1) In the check valve of the present invention, the check valve body includes a valve packing that can be seated on the check valve seat and a holder to which the valve packing is attached, and one end side of the holder includes the valve packing. The relief valve seat is formed at the distal end of the guide cylinder, penetrating to the primary side, the guide cylinder extending coaxially in the secondary direction is formed on the other end, and the support shaft slides on the guide cylinder. The relief valve body is attached to the support shaft at a position outside the check valve body by penetrating the check valve body to the primary side. A guide portion for slidingly guiding the support shaft is formed, and a second urging member is interposed between the guide tube portion and the support shaft so that the relief valve body is moved to the relief valve seat. A configuration in which it is urged in the seating direction is preferable.
According to such a configuration, the relief valve body is attached to the support shaft, and the support shaft is guided to slide by the guide portion formed on the guide tube portion of the holder. At this time, since the cylindrical portion is formed to extend in the secondary direction, a long region for guiding the sliding of the support shaft can be secured long, and the opening and closing operation of the relief valve body is smoothly performed. be able to.
(2) Further, the check valve seat is formed, and has a housing in which the check valve body, the relief valve body, the first urging member and the second urging member are incorporated, An end portion extending in the secondary direction of the guide tube portion is supported by a holding member attached to the housing, and the first urging member is interposed between the holding member and the check valve body. May be interposed.

  According to such a configuration, since the extending end portion in the secondary side direction of the guide tube portion is supported by the holding member attached to the housing, the sliding operation of the support shaft becomes more stable. Therefore, the opening and closing operation of the relief valve body can be made smoother.

Next, a first embodiment in which the check valve of the present invention is embodied will be described with reference to the drawings.
<Example 1>
The check valve 1 of the present embodiment can be used by being incorporated in a hot water supply circuit including a hot water heater, for example. FIG. 1 shows a state in which a check valve 1 according to Embodiment 1 of the present invention is incorporated in a pipe 2. In the figure, the right side of the check valve 1 is the primary side, and the left side is the secondary side. A housing 3 of the check valve 1 is formed in a cylindrical shape from a synthetic resin material, and a fluid passage 4 is formed therein. A check valve seat 6 on which the check valve body 5 can be seated is formed at a position slightly inward from the primary side opening in the housing 3. On the other hand, a holding member 7 is assembled to the secondary side opening of the housing 3.

  The holding member 7 has a ring-shaped attachment portion 8 formed on the outer peripheral side, and a holding cylinder 9 extending in the axial direction at the center. The attachment portion 8 and the holding cylinder 9 are connected by a plurality of connecting pieces 10 that extend radially, and between the connecting pieces 10 are openings 11 through which fluid passes. An insertion hole 19 that slidably supports the holder 12 of the check valve body 5 is formed in the holding cylinder 9 so as to penetrate along the axial direction.

  The check valve body 5 includes a valve packing 18 that can be seated on the check valve seat 6 and a holder 12 that supports the valve packing 18. The valve packing 18 is formed of a rubber material, and the whole is formed in a disk shape. A central portion of the valve packing 18 is thick, and a thick portion 18A is formed that rises in a disc shape in both directions.

  The holder 12 is integrally formed of a synthetic resin material and has a disc-shaped base portion 12A. The base portion 12A is formed to have substantially the same diameter as the outer diameter of the valve packing 18, and a tapered surface 20 is formed on the outer peripheral edge so as to be inclined downward in the secondary side direction. At the center of the surface of the base portion 12A that faces the valve packing 18, a mounting cylinder portion 12B projects toward the primary side. A valve packing 18 is coaxially inserted into the mounting cylinder portion 12B. On the outer peripheral surface near the tip of the mounting cylinder portion 12B, a retaining piece 24 projects outward in the radial direction over the entire circumference, and the thick portion 18A of the valve packing 18 is sandwiched between the base portion 12A and the base portion 12A. The valve packing 18 is attached in a retaining state. Further, a relief valve seat 25 projects from the distal end surface of the mounting cylinder portion 12B in the axial direction.

  A guide tube portion 12C is projected from the surface of the base portion 12A opposite to the side on which the mounting tube portion 12B is formed toward the secondary side. The guide tube portion 12C is coaxial with the mounting tube portion 12B and has an outer diameter larger than that of the mounting tube portion 12B. The guide cylinder portion 12C is slidably inserted into the insertion hole 19 of the holding cylinder 9 in the holding member 7, and the tip penetrates to the secondary side. In addition, a first spring 17 is interposed between the base 12A of the holder 12 and a portion of the holding member 7 around the holding cylinder 9 around the guide cylinder 12C. The first spring 17 biases the check valve body 5 in the closing direction, that is, in the direction in which the valve packing 18 is seated on the check valve seat 6.

  A through hole 22 is formed in the holder 12 along the axial center, and the support shaft 13 is slidably passed through the through hole 22 coaxially. The through hole 22 is set to have a diameter slightly larger than the outer diameter of the support shaft 13 except for a spring housing portion 12D described later.

  The distal end side of the support shaft 13 protrudes from the attachment cylinder portion 12B to the primary side, and a relief valve body 26 is attached to the protruding distal end portion. That is, a head 13A is integrally formed at the tip of the support shaft 13, and a cap-shaped metal holder 27 fitted into the support shaft 13 is fixed to the head 13A. A rubber valve member 28 is attached in a press-fit state. The end face and the outer peripheral surface of the head 13 </ b> A side are covered with the receiving member 27, but the surface of the valve member 28 facing the relief valve seat 25 is exposed and can be directly seated on the relief valve seat 25. Yes.

  On the other hand, a pressure introduction hole 29 for releasing the pressure on the secondary side and acting on the valve body 26 is opened at the base portion with respect to the base portion 12A side in the guide cylinder portion 12C. As shown in FIG. 4, a pair of the pressure introducing holes 29 are formed so as to penetrate the wall surface of the guide cylinder portion 12 </ b> C along the diameter direction, and communicate with the through holes 22. Further, in the formation region from the base portion 12A to the mounting cylinder portion 12B in the through hole 22, relief passages 23 are arranged around the through hole 22 at intervals of about 90 degrees as shown in FIG. Each escape channel 23 is formed along the axial direction in the formation region. Thus, the secondary pressure can be applied to the valve member 28 via the pressure introducing hole 29 and the relief passages 23. In addition, guide ridges 30 extending relatively in the axial direction are arranged between the escape passages 23 so as to surround the support shaft 13, and can guide the sliding operation of the support shaft 13.

  In the through hole 22 in the guide tube portion 12C, the half region on the base portion 12A side in the axial direction is slightly larger than the outer diameter of the support shaft 13 as described above, and thereby the base portion 12A side of the guide tube portion 12C. Is a guide portion 12E capable of guiding the sliding of the support shaft 13. On the other hand, the front end side in the axial direction of the through hole 22 is formed to have a large diameter, and serves as the spring accommodating portion 12D that accommodates the second spring 16 (second urging member). The distal end side of the support shaft 13 protrudes through the spring accommodating portion 12D in the secondary direction, and a stopper plate 15 is attached to the distal end portion via a retaining ring 14. The second spring 16 is interposed between the stopper plate 15 and the inner wall in the spring accommodating portion around the support shaft 13 and urges the support shaft 13 to be displaced in the secondary direction along the axial direction. doing. As a result, normally, the stopper plate 15 is at a position axially separated from the tip of the spring accommodating portion 12D. However, when excessive pressure is generated on the secondary side, the support shaft 13 resists the second spring 16. Then, it moves toward the primary side to open the relief valve body 26. At that time, the stopper plate 15 abuts against the distal end surface of the spring accommodating portion 12D to restrict the movement stroke of the support shaft 13.

  Next, the operation and effect of the present embodiment configured as described above will be described. In the state where no fluid flows in the pipe 2, as shown in FIG. Since the body 5 is seated on the check valve seat 6, back flow from the secondary side to the primary side is prevented. Further, since the support shaft 13 is urged to the left in the drawing by the spring force of the second spring 16, even if the pressure on the secondary side in the pipe 2 increases, the degree of the pressure is the second spring. As long as it is within the range of 16 spring forces, the relief valve body 26 is held in a state of being seated on the relief valve seat 25.

  When fluid begins to flow into the pipe 2, the primary water flow pressure acts on the valve packing 18 of the check valve body 5 as shown in FIG. 2. Then, while the first spring 17 is compressed, the check valve body 5 is separated from the check valve seat 6 and is opened. As a result, the fluid passes through the inside of the check valve seat 6 and enters the housing 3, and further flows in the pipe 2 to the secondary side through the openings 11 between the connecting pieces 10 of the holding member 7. At this time, the relief valve body 26 is seated on the relief valve seat 25 by the second spring 16 and is held in the closed state.

  Next, for example, when the water tap is rapidly closed, the check valve body 5 is seated on the check valve seat 6 by the spring force of the first spring 17 when the water flow is stopped, and the valve is closed. The water hammer phenomenon may occur on the secondary side, and the pressure in the secondary side pipe 2 may be increased at once. In such a case, excessive pressure generated on the secondary side acts on the valve member 28 of the relief valve body 26 via the pressure introduction hole 29 and each relief flow path 23. As a result, the relief valve element 26 opens away from the relief valve seat 25 while compressing the second spring 16, so that the pressure generated on the secondary side can be released to the primary side. Since excessive secondary pressure on the secondary side is relieved in this way, a situation in which the check valve body 5 is deformed or damaged can be avoided.

  In addition, according to the present embodiment, since the relief valve body 26 is arranged outside the check valve body 5, unlike the conventional case, a storage space for the relief valve body 26 is secured inside the check valve body 5. There is no need to do. Therefore, the check valve body 5 can be reduced in size, and thereby, the cross-sectional area of the fluid passage 4 held between the inner wall of the housing 3 and the check valve body 5 can be secured widely. While being able to reduce the pressure loss of the fluid in normal time, the check valve 1 whole can be reduced in size.

  In addition, since the long guide cylinder portion 12C is formed in the holder 12 and thereby guides the sliding of the support shaft 13, the opening and closing operations of the relief valve body 26 can be performed smoothly. it can.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) In the above embodiment, the relief valve body 26 has a two-body structure including the metal receiving member 27 and the rubber valve member 28. However, the receiving member 27 can be omitted by changing the shape of the head 13A. It is.
(2) In the above embodiment, the support plate 13 is provided with the stopper plate 15 and the retaining ring 14 to prevent the second spring 16 from coming off, but the stopper plate 15 has a locking structure for the support shaft 13. In this case, the retaining ring 14 can be omitted.
(3) In the above embodiment, the entire check valve 1 is incorporated in the housing 3, but the housing can be omitted. In that case, the check valve seat 6 and the like are integrally formed in the pipe 2.

DESCRIPTION OF SYMBOLS 1 ... Check valve 3 ... Housing 4 ... Fluid passage 5 ... Check valve body 6 ... Check valve seat 7 ... Holding member 12 ... Holder 12C ... Guide cylinder part 13 ... Support shaft 16 ... 2nd spring (2nd urging | biasing) Element)
17 ... 1st spring (1st biasing member)
23 ... Relief passage 25 ... Relief valve seat 26 ... Release valve body

Claims (3)

A check valve seat formed in a fluid passage leading to the primary side and the secondary side;
It has an escape passage that leads from the secondary side to the primary side, and a relief valve seat is formed at the primary side end of the escape passage, and it can be seated on the check valve seat to close and open the fluid passage Non-return valve body,
A first urging member that urges the check valve body in a direction to be seated on the check valve seat;
A relief valve element which is arranged outside the check valve element and is seated on the relief valve seat so as to close and release the relief flow path;
A check valve comprising: a second urging member that urges the relief valve body in a direction to be seated on the relief valve seat. The check valve body includes a valve packing that can be seated on the check valve seat and a holder to which the valve packing is attached, and one end of the holder penetrates the valve packing to the primary side, and the tip of the check valve body A relief valve seat is formed, and the other end side is formed with a guide cylinder portion extending coaxially in the secondary direction,
A support shaft is slidably provided in the guide tube portion, and the check valve body passes through the support shaft to the primary side, and the relief valve body is positioned outside the check valve body. And a guide portion for sliding and guiding the support shaft is formed in the guide tube portion, and a second urging member is interposed between the guide tube portion and the support shaft. The check valve according to claim 1, wherein the check valve is biased in a direction in which the relief valve body is seated on the relief valve seat. The check valve seat is formed, and has a housing in which the check valve body, the relief valve body, the first urging member and the second urging member are incorporated,
An end portion extending in the secondary direction of the guide tube portion is supported by a holding member attached to the housing, and the first urging member is interposed between the holding member and the check valve body. The check valve according to claim 2, wherein a check valve is interposed.

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