JP6289978B2 - Check valve - Google Patents

Description

  The present invention relates to a check valve that is provided in an internal passage such as a hot-water mixing tap or a stop cock and prevents a fluid from flowing backward from the downstream side to the upstream side.

  Generally, this type of check valve has a main body, a valve body, and a coil spring as described in Patent Document 1 below. For example, the main body is fixedly provided in the internal passage of the hot and cold water mixing tap. By providing the main body in the internal passage, the internal passage of the mixing plug is divided into an upstream portion located upstream from the main body and a downstream portion located downstream. A passage hole is formed in the main body to allow communication between the upstream portion and the downstream portion. A valve seat surrounding the opening of the passage hole is formed in an annular shape on the downstream end face of the main body where the passage hole opens.

  The valve body is movably provided in the main body in a state where most of the valve body is positioned downstream of the valve main body. The valve body can move between a closed position where the valve body is seated on the valve seat and an open position which is spaced from the valve seat. When the valve body is located at the closed position, the passage hole is closed, and the upstream portion and the downstream portion are blocked by the valve body. On the contrary, when the valve body is located at the open position, the passage hole is opened, and the upstream portion and the downstream portion communicate with each other through the passage hole.

The coil spring urges the valve body from the open position toward the closed position, and positions the valve body in the closed position when the hot and cold water mixing tap is not used (when closed). The biasing force of the coil spring is smaller than the force with which the fluid in the passage hole pushes the valve body downstream. Therefore, the valve body is moved to the open position by the hot water in the passage hole when the hot / cold water mixing tap is used (when opened). As a result, the passage hole is opened and the fluid in the upstream portion flows through the passage hole to the downstream portion.

  When the hot water / water mixing tap is closed in a state where the valve body is in the open position, the flow of the fluid in the internal passage stops and the fluid does not press the valve body. Then, the valve body is moved from the open position to the closed position by the coil spring. As a result, the passage hole is closed, and the fluid in the downstream portion is prevented from flowing back to the upstream portion through the passage hole.

Japanese Utility Model Publication No. 5-52452

  If the hot / cold mixing tap is suddenly changed from the use state to the non-use state, that is, if the tap valve body of the hot / cold mixing tap is moved from the open position to the closed position at a high speed, there is a gap between the plug valve body and the check valve. A large pressure wave is generated in the downstream part located at. Due to this pressure wave, the fluid in the downstream portion may pass between the valve element and the valve seat and flow back into the upstream portion.

In order to solve the above-described problem, the present invention provides a valve seat that has a passage hole formed therethrough and that surrounds the opening of the passage hole on the downstream end surface where the downstream end of the passage hole opens. Is formed to be movable in the upstream and downstream sides of the main body, and the valve body opens and closes the passage hole by being separated from and seated on the valve seat. Urging means for urging upstream and seating on the valve seat, a contact member is provided on a surface of the valve body facing the valve seat, and the valve body contacts the valve seat. In a check valve that is seated via a contact member and the contact member is made of an elastic material, the downstream side end surface of the main body has a portion on the inner peripheral side of the valve seat on the downstream side. A cylindrical wall surface extending from the end face toward the upstream side is formed in an annular shape, and the main body of the contact member When the upstream pressing force acting on the valve body exceeds a predetermined magnitude, an abutting wall surface that presses and contacts the entire cylindrical wall surface is formed in an annular shape on the opposite surface of It is a feature.
In this case, a valve portion seated on the valve seat is formed on the surface of the contact member facing the main body, and an annular groove is formed in a portion adjacent to the valve portion of the facing surface on the inner peripheral side. The abutting wall surface is desirably formed on the inner peripheral side surface of the annular groove.
The abutting wall surface is formed in a tapered shape so as to have a larger diameter toward the downstream side, and the diameter of the abutting wall surface is smaller than the diameter of the cylindrical wall surface at the upstream end, When the acting upstream pressing force exceeds the predetermined magnitude and the valve body and the contact member are moved to the upstream side, the downstream portion of the contact wall surface from the upstream end is It is desirable that the diameter of the intermediate portion in the upstream and downstream direction of the contact wall surface is set to be the same as the diameter of the tubular wall surface so as to abut against the cylindrical wall surface.
A protruding portion having an outer peripheral surface coaxial with the valve seat is formed in a portion on the inner peripheral side of the valve portion seated on the valve seat in a surface facing the valve body of the contact member. It is desirable that the abutting wall surface be formed on the outer peripheral surface.
The diameter of the abutting wall surface at the base end portion of the projecting portion is substantially the same as the diameter of the intersecting portion between the cylindrical wall surface and the downstream end surface of the main body, and the upstream pushing force acting on the valve body is pushed. When the pressure exceeds the predetermined size, the outer peripheral side portion of the contact member pressed against the valve seat is elastically deformed so that a part of the contact member enters between the cylindrical wall surface and the contact wall surface. As a result, it is desirable that the abutting wall surface is in press contact with the cylindrical wall surface via the part.

  According to the present invention having the above-described characteristic configuration, when a pressure exceeding a predetermined size acts on the valve body toward the upstream side, the abutting wall surface of the abutting member comes into annular contact with the cylindrical wall surface of the main body. . That is, the abutting member is pressed against the main body at two locations of the valve seat and the cylindrical wall surface. Therefore, the space between the contact member of the valve body and the main body is more highly sealed. Therefore, it is possible to reliably prevent the fluid in the internal passage on the downstream side of the check valve from flowing back to the upstream side through the check valve.

FIG. 1 is a front view showing a hot and cold water mixing tap provided with a check valve according to the present invention. FIG. 2 is a plan view of the hot water / water mixing tap. FIG. 3 is a side view of the hot water / water mixing tap. FIG. 4 is a partially omitted enlarged cross-sectional view taken along line XX of FIG. 2, and shows the first embodiment of the check valve according to the present invention provided in the internal passage of the hot and cold water mixing tap. Has been. FIG. 5 is a cross-sectional view showing the first embodiment of the check valve according to the present invention in a closed state. FIG. 6 is a cross-sectional view showing the first embodiment in an open state. FIG. 7 is a cross-sectional view showing the first embodiment in a state where a pressure smaller than a predetermined magnitude is applied to the valve body. FIG. 8 is a cross-sectional view showing the first embodiment in a state where a pressure exceeding a predetermined level is applied to the valve body. FIG. 9 is a view of the valve body used in the first embodiment viewed from the X direction in FIG. 5. FIG. 10 is an exploded perspective view of the first embodiment. FIG. 11 is a sectional view showing a check valve in a closed state according to a second embodiment of the invention. FIG. 12 is a cross-sectional view showing the second embodiment in an open state. FIG. 13 is a cross-sectional view showing the second embodiment in a state where a pressure exceeding a predetermined level is applied to the valve body. FIG. 14 is an enlarged view of a main part of FIG. FIG. 15 is an enlarged view of a main part of FIG.

The best mode for carrying out the present invention will be described below with reference to the drawings.
1 to 4 show a hot and cold water mixing tap A provided with a check valve 1 according to the present invention. Of course, the check valve 1 is not used only for the hot and cold water mixing plug A, but can be used for various other known plugs.

  The hot and cold water mixing property A has first and second supply pipes B and C. One end (upstream end) of the first and second supply pipes B and C is attached to a wall portion such as a bathroom. It is fixed. Thereby, the whole hot-water mixing tap A is being fixed to the wall part. Water such as tap water is supplied to the upstream end of the first supply pipe B. Hot water is supplied to the upstream end of the second supply pipe C. A mixing pipe D is connected to the downstream ends of the first and second supply pipes B and C via connection pipes E and E.

  As shown in FIG. 4, the connection pipe E has a first pipe body E1, a second pipe body E2, and a nut E3. The upstream end of the first pipe body E1 is screwed and fixed to the downstream end of the first supply pipe B, and the inside communicates with the inside of the first supply pipe B. The downstream end of the second tube E2 is screwed and fixed to the mixing tube D, and the inside thereof communicates with the inside of the mixing tube D. The downstream end of the first tube E1 and the upstream end of the second tube E2 are connected and fixed by a nut E3. As a result, the first supply pipe B is connected to the mixing pipe D via the connection pipe E, and the water supplied to the first supply pipe B flows into the mixing pipe D through the connection pipe E. Similarly, the second supply pipe C is also connected to the mixing pipe D via the connection pipe E, and the hot water supplied to the second supply pipe C flows into the mixing pipe D through the connection pipe E. Then, water and hot water are mixed in the mixing tube D. A plug valve body (not shown) is provided in the mixing tube D. When the stopper valve body is positioned at the open position, the mixed water of hot and cold water mixed in the mixing pipe D flows out from the outlet pipe F. When the stopper valve body is positioned at the closed position, the outflow of mixed water from the water discharge pipe F stops.

  A temperature adjusting knob G is provided at one end of the mixing tube D (the left end in FIGS. 1 and 2). The temperature of the mixed water is adjusted by rotating the temperature adjusting knob G to an appropriate position. An opening / closing handle H is provided at the other end of the mixing tube D. The opening / closing handle H is used to open / close the stopper valve body. When the opening / closing handle H is rotated to the open position, the mixed water flows out from the drain pipe F. When the opening / closing handle H is rotated to the closed position, the outflow of mixed water from the water discharge pipe F stops. In addition, the outflow amount of the mixed water from the water discharge pipe F can be appropriately adjusted according to the rotational position of the opening / closing handle H.

An internal passage I of the hot and cold water mixing tap A is constituted by the inside of the first supply pipe B, the second supply pipe C, the connection pipes E and E, the mixing pipe D, and the outlet pipe F. Check valves 1 and 1 according to the present invention are provided in the connection pipes E and E constituting the internal passage I, respectively. One check valve 1 allows water in the first supply pipe B to flow into the mixing pipe D through the one connection pipe E, but the mixed water in the mixing pipe D is allowed to flow into the first supply pipe B. To prevent backflow. The other check valve 1 allows hot water in the second supply pipe C to flow into the mixing pipe D through the other connection pipe E, but the mixed water in the mixing pipe D is allowed to flow into the second supply pipe C. To prevent backflow.

Further, the check valves 1 and 1 are provided in the connection pipes E and E, respectively, so that the internal passage I of the mixing plug A is located upstream of the check valves 1 and 1, and upstream portions Ia and Ia. And the downstream portions Ib and Ib located between the plug valve body and the check valves 1 and 1. When the valve body for stopper is closed from the open state at a high speed, a shock wave is generated in the downstream portion Ib.

Next, the check valve 1 according to the present invention will be described. As shown in FIGS. 5 to 10, the check valve 1 includes a packing 2, a main body 3, a movable member 4, a valve body 5 and a contact member 6. It is the main component. Since the check valves 1 and 1 provided in the two connection pipes E and E have the same configuration, only one check valve 1 will be described.

The packing 2 is made of a material having moderate elasticity and high strength, for example, a relatively hard rubber, and is formed in a short cylindrical shape having a circular cross section. An attachment recess 2 a that extends in an annular shape is formed at a substantially central portion in the longitudinal direction of the inner peripheral surface of the packing 2. As shown in FIG. 4, the packing 2 configured in this manner is disposed between the downstream end face (the lower end face in FIG. 4) of the first tubular body E <b> 1 and the upstream end face of the second tubular body E <b> 2. It is pressed against both end faces by tightening the nut E3. Accordingly, the packing 2 is fixed between the first and second tubular bodies E1 and E2, and the end surfaces of the first and second tubular bodies E1 and E2 are sealed by the packing 2.

The main body 3 is made of a metal such as stainless steel or a hard resin, and has a cylindrical main portion 3 a as shown in FIGS. 5 to 8 and 10. The upstream end of the main portion 3 a is inserted into the packing 2. On the outer peripheral surface of the main portion 3a inserted into the packing 2, a mounting protrusion 3h extending in the circumferential direction is formed. The mounting protrusion 3 h is inserted into the mounting recess 2 a of the packing 2. In addition, both end surfaces (upper and lower end surfaces in FIG. 5) of the mounting protrusion 3h are attached to the mounting recess 2a by the packing 2 being pushed and compressed elastically by the first and second tubular bodies E1 and E2. Is pressed against both sides. As a result, the main body 3 is fixed to the connecting pipe E via the packing 2, and the space between both end surfaces of the mounting protrusion 3h and both side surfaces of the mounting recess 2a is sealed, and consequently the outer peripheral surface of the main portion 3a. And the inner peripheral surface of the packing 2 are sealed.

An annular protrusion 3b is formed at the downstream end of the inner peripheral surface of the main portion 3a. A cylindrical portion 3c extending toward the upstream side is formed on the inner peripheral portion of the annular projecting portion 3b. The inside of the main part 3a and the cylinder part 3c is a passage hole 3d. Water (hot water) that has flowed into the upstream end portion of the connection pipe E (E) from the first supply pipe B (second supply pipe C) enters the passage hole 3d. Then, after flowing toward the downstream side in the passage hole 3d, it flows into the mixing pipe D through the downstream end of the connection pipe E (E).

Of the surface facing the downstream side of the annular protrusion 3b, the annular portion adjacent to the opening on the downstream side of the passage hole 3d is the valve seat 3e. The valve seat 3e is arranged so that its center is located on the axis of the main portion 3a. Although the valve seat 3e is configured by a plane orthogonal to the axis of the main portion 3a, an annular protrusion may be formed on the surface facing the downstream side of the annular protrusion 3b, and this protrusion may be used as the valve seat.

A portion on the tip side of the inner peripheral surface of the cylindrical portion 3c is a cylindrical wall surface 3f. The cylindrical wall surface 3f is constituted by a straight cylindrical surface having a circular cross section, and is arranged such that its axis coincides with the axis of the main portion 3a. The cylindrical wall surface 3f may be configured by a tapered surface having a smaller diameter toward the upstream side. The intersection between the cylindrical wall surface 3f and the valve seat 3e is smoothly connected by a circular arc surface. A receiving portion 3g is formed on the upper end surface of the cylindrical portion 3c. Although the receiving part 3g is comprised by the plane orthogonal to the axis line of the main part 3a, you may comprise by the curved surface convex toward the upstream.

The movable member 4 is made of metal or hard resin, and has an annular portion 4a having a circular cross section. The annular portion 4a is slidably fitted to the main portion 3a. A plurality of support arm portions 4b extending radially inward are formed on the inner peripheral surface of the annular portion 4a. The support arm portions 4b are spaced apart from each other in the circumferential direction. Therefore, the water (hot water) flowing into the upper end portion of the main portion 3a can flow between the two support arm portions 4b and 4b adjacent in the circumferential direction to the downstream side of the support arm portion 4b. The gap between the two support arm portions 4b, 4b adjacent in the circumferential direction is wide enough to allow water (hot water) to flow. A support tube portion 4c is provided at the tip of each support arm portion 4b. The support cylinder portion 4c has a circular cross section, and is arranged such that its axis coincides with the axis of the annular portion 4a.

A compression coil spring (biasing means) 7 is provided between the annular protrusion 3 b of the main body 3 and the annular portion 4 a of the movable member 4. By this compression coil spring 7, the movable member 4 is urged to the upstream side (the upper side in FIGS. 5 to 8). When the hot water mixing tap A is not in use and mixed water is not flowing in the internal passage I, the movable member 4 is positioned at the closed position shown in FIG. When the movable member 4 is located at the closed position, as will be described later, the valve body 5 is seated on the valve seat 3e via the contact member 6 to close the passage hole 3d. This prevents the mixed water in the downstream portion Ib from flowing back into the upstream portion Ia. When the hot water mixing tap A is used, the movable member 4 is moved to the open position shown in FIG. 6 against the urging force of the compression coil spring 7 by the water (hot water) flowing toward the downstream side in the passage hole 3d. The open position is determined by the movable member 4 abutting against the receiving portion 3g of the main body 3. When the movable member 4 is located at the open position, the valve body 5 and the contact member 6 are separated from the valve seat 3e to the downstream side, and the passage hole 3d is opened. Accordingly, water (hot water) in the upstream portion Ia flows into the downstream portion Ib through the passage hole 3d.

The valve body 5 has a disk portion 5a. The disc part 5a is arrange | positioned downstream from the main part 3a and the support cylinder part 4c, and the axis line is arrange | positioned with the axis line of the support cylinder part 4c. The outer diameter of the disc part 5a has substantially the same outer diameter as the outer diameter of the valve seat 3e. Therefore, the outer peripheral portion of the end surface facing the upstream side of the disc portion 5a faces the valve seat 3e. Note that when the movable member 4 moves to the closed position, the disc portion 5a is seated on the valve seat 3e via a contact member 6 described later.

A shaft portion 5b having a circular cross section is formed on the end surface facing the upstream side of the disc portion 5a so that its axis coincides with the axis of the disc portion 5a. The shaft portion 5b is inserted into the support cylinder portion 4c in a penetrating state. On the outer peripheral surface of the tip end portion (upstream end portion) of the shaft portion 5b protruding upstream from the support cylinder portion 4c, an engagement protrusion portion 5c is formed in an annular shape. The outer diameter of the engagement protrusion 5c is larger than the inner diameter of the support cylinder 4c. When the engagement protrusion 5c hits the upstream end surface of the support cylinder 4c, the shaft 5b is supported by the support cylinder. It is prevented from coming out of 4c downstream. A tapered portion 5d having a smaller diameter toward the upstream side is formed at the tip of the shaft portion 5b following the engaging protrusion 5c. The outer diameter of the upper end portion of the taper portion 5d, that is, the minimum outer diameter of the taper portion 5d is smaller than the inner diameter of the support cylinder portion 4c.

One or a plurality of slits 5e (in this embodiment, two as shown in FIG. 10) that cross the shaft portion 5b in the radial direction are formed on the tip surface (the end surface facing the upstream side) of the shaft portion 5b. Has been. Thereby, the front-end | tip part of the axial part 5b can elastically expand / contract diameter. Moreover, the slit 5e extends to the downstream side from the engagement protrusion 5c. Thus, the distal end portion of the shaft portion 5b can be elastically reduced in diameter until the outer diameter of the engagement protrusion portion 5c becomes smaller than the inner diameter of the support cylinder portion 4c. Therefore, by reducing the diameter of the tip of the shaft portion 5b, the shaft portion 5b can be inserted into the support cylinder portion 4c from the opening on the downstream side. In addition, when the distal end portion of the shaft portion 5b is inserted into the support cylinder portion 4c, the taper portion 5d hits the intersection of the inner peripheral surface of the support tube portion 4c and the downstream end surface of the support tube portion 4c, and the shaft portion 5b. Reduce the diameter of the tip. Therefore, the shaft portion 5b can be easily inserted into the support cylinder portion 4c. When the engaging protrusion 5c passes through the support cylinder 4c, the tip of the shaft 5c expands to its original outer diameter due to its own elasticity. Then, the engagement protrusion 5c engages with the upstream end surface of the support cylinder 4c, and the shaft 5b cannot come out of the support cylinder 4c downstream.

A restriction hole 5f is formed in the distal end surface of the shaft portion 5b so that its axis line coincides with the axis line of the shaft portion 5b. The restriction hole 5f extends downstream from the slit 5e. A restriction shaft 8 is inserted into the restriction hole 5f. The outer diameter of the restricting shaft 8 is substantially the same as the inner diameter of the restricting hole 5f when the distal end portion of the shaft portion 5b is in a natural state where the diameter is not expanded or reduced. Therefore, when the restriction shaft 8 is inserted into the restriction hole 5f, the tip end portion of the shaft portion 5b cannot be reduced in diameter, and the engagement protrusion 5c is reliably engaged with the surface facing the upstream side of the support cylinder portion 4c. . This reliably prevents the shaft portion 5b from coming out of the support cylinder portion 4c to the downstream side. A locking projection 5g is formed at the upper end of the inner peripheral surface of the restriction hole 5f. The locking projection 5g abuts against the end surface facing the upstream side of the restriction shaft 8, so that the restriction shaft 8 is prevented from coming out of the restriction hole 5f to the upstream side.

The restriction shaft 8 can be inserted into the restriction hole 5f as follows. First, the shaft part 5b is inserted into the support cylinder part 4c, and the engagement protrusion part 5c is protruded upstream from the support cylinder part 4c. As a result, the shaft portion 5c is returned to the original state where the diameter is not enlarged or reduced. Next, the shaft part 5b is moved upstream with respect to the support cylinder part 4c. Actually, as will be described later, the contact member 6 is interposed between the support cylinder portion 4c and the disc portion 5a. Therefore, the contact member 6 is elastically compressed and deformed, and the shaft portion 5b is moved upstream by the amount of the compression deformation. Then, since the length of the upstream end portion of the shaft portion 5b protruding upstream from the support cylinder portion 4c is increased, the tip end portion of the shaft portion 5b can be elastically expanded. The diameter of the tip of the shaft 5b is increased, and the diameter of the upstream end of the restriction hole 5f, particularly the portion where the locking projection 5g is formed, is increased. Then, the restriction shaft 8 is inserted into the restriction hole 5f. When the regulating shaft 8 passes through the locking projection 5g, the tip of the shaft portion 5b is reduced in diameter by its own elasticity, and the locking projection 5g engages with the upstream end surface of the regulating shaft 8. As a result, the restriction shaft 8 is inserted into the restriction hole 5f in a retaining state.

After inserting the regulating shaft 8 into the mounting hole 4d in this way, the shaft portion 5b is moved downstream until the contact member 6 that has been compressed and deformed returns to its original state. Then, the tip portion of the shaft portion 5b moves downstream by the amount that the contact member 6 has returned to its original state, and is inserted into the mounting hole 4d. As a result, the tip end portion of the shaft portion 5b cannot be greatly enlarged, and the locking projection 5g is maintained in a state of being engaged with the restriction shaft 8. Therefore, the restriction shaft 8 is reliably prevented from coming out of the mounting hole 4d. Therefore, the engagement protruding portion 5c is kept engaged with the upstream end surface of the support cylinder portion 4c, and the shaft portion 5b is prevented from coming out of the mounting hole 4d to the downstream side.

As shown in FIG. 9, an outer ridge 5h and an inner ridge 5i are formed on the end face on the downstream side of the disc portion 5a so as to extend annularly about the axis of the disc portion 5a. The outer protrusion 5h is arranged so that the outer peripheral edge thereof coincides with the outer peripheral edge of the disc portion 5a. The inner ridge 5i is disposed so as to be located at the approximate center between the axis of the disc portion 5a and the outer ridge 5h. Between the outer ridge 5h and the inner ridge 5i, a plurality (four in this embodiment) of radial ridges 5j extending in the radial direction are arranged at equal intervals in the circumferential direction. By forming the outer protrusion 5h, the inner protrusion 5i, and the radial protrusion 5i, five concave portions 5k are formed on the end surface facing the downstream side of the disk portion 5a.

The reason for forming the recess 5k is as follows. That is, when a shock wave is generated, the shock wave collides with an end face on the downstream side of the disc portion 5a. In this case, there is no problem if the shock wave collides with each part of the end face on the downstream side of the disk part 5a simultaneously and uniformly, but there is a slight time shift in the collision of the shock wave with the disk part 5a. And non-uniformity of force acting on each part. For this reason, when the shock wave reaches the disk part 5a, the disk part 5a tilts, that is, a part of the disk part 5a in the circumferential direction is located on the downstream side and a part located on the opposite side of the circumferential direction is upstream. The disc portion 5a is inclined so as to be located on the side. Then, as a result of the shock wave hitting a part located on the upstream side immediately flowing outward from the disc portion 5a and coming off, the disc portion 5a tilts in the opposite direction at the next moment. As a result of the change in the inclination of the disc portion 5a in this way, there is a problem that the disc portion 5a is vibrationally rattling.

However, when the recess 5k is formed by the protrusions 5h, 5i, and 5j, a difference occurs in the arrival time of the shock wave to the disc portion 5a, and as a result, even if the disc portion 5a is inclined, The entering shock wave remains in the recess 5k. Therefore, the inclination of the disk part 5a is returned when all the shock waves reach the disk part 5a. Therefore, it is possible to prevent the disk portion 5a from rattling vibrationally.

A contact member 6 is provided on the surface facing the upstream side of the disc portion 5a. The contact member 6 is made of a material having both moderate elasticity and sealing properties such as relatively hard rubber, and is formed in a disk shape. And the contact member 6 is mounted in the surface which faces the upstream of the disc part 5a in the state which made the axis line correspond with the axis line of the disc part 5a. Both end surfaces of the contact member 6 are configured by planes orthogonal to the axis of the contact member 6. The outer diameter of the contact member 6 has substantially the same outer diameter as that of the disc portion 5a. Therefore, the outer peripheral portion of the surface facing the upstream side of the contact member 6 faces the valve seat 3e, and the outer peripheral portion is a valve portion 6a that is seated on and separated from the valve seat 3e.

A through hole 6 b is formed at the center of the contact member 6. The base end portion of the shaft portion 5b is inserted into the through hole 6b. The inner diameter of the through hole 6b is set smaller than the outer diameter of the shaft portion 5b by a predetermined dimension. Therefore, the inner peripheral surface of the through-hole 6b is brought into press contact with the outer peripheral surface of the shaft portion 5b by the elasticity of the contact member 6 itself. Thereby, the space between the inner peripheral surface of the through hole 6b and the outer peripheral surface of the shaft portion 5b is sealed.

The center part of the contact member 6 is clamped in an elastically compressed state by the disk part 5a and the support cylinder part 4c. As a result, the upstream and downstream end surfaces of the abutting member 6 are pressed against the surface facing the upstream side of the disk portion 5a and the surface facing the downstream side of the support cylinder portion 4c by the elasticity of the abutting member 6 itself. It has been. Thereby, the space between the contact surfaces of the contact member 6, the disk portion 5a, and the support cylinder portion 4c is sealed. You may seal between the contact surfaces of the contact member 6, the disc part 5a, and the support cylinder part 4c by adhere | attaching them.

The abutting member 6 is sandwiched in an elastically compressed state by the disc portion 5a and the support cylinder portion 4c. Accordingly, the abutting member 6 biases the disc portion 5a to the downstream side. And the engagement protrusion part 5c is pressed by the surface which faces the upstream of the support cylinder part 4c with the urging | biasing force. That is, the engagement protrusion 5c is pressed against the upstream end face of the support cylinder 4c, and the disc part 5a is pressed via the contact member 6 to the downstream end face of the support cylinder 4c. Yes. In other words, the support cylinder part 4c is clamped by the disk part 5a and the engagement protrusion part 5c via the contact member 6. As a result, the valve body 5 and the contact member 6 are fixed to the support cylinder portion 4c. Therefore, the valve body 5 and the contact member 6 move to the upstream side and the downstream side together with the movable member 4.

When the hot-water mixing tap A is not used, the pressure in the upstream portion Ia and the pressure in the downstream portion Ib are the same. Therefore, the valve body 5 and the contact member 6 are moved to the upstream side by the compression coil spring 7 together with the movable member 4 to the closed position shown in FIG. When the valve body 5 and the contact member 6 move to the closed position, the valve portion 6a of the contact member 6 is seated on the valve seat 3e, and the passage hole 3d is closed. Therefore, the mixed water in the downstream portion Ib does not flow into the upstream portion Ia. When the hot water mixing tap A is used, the valve body 5 and the contact member 6 are moved downstream against the urging force of the compression coil spring 7 by the water (hot water) flowing through the passage hole 3d. As shown in FIG. 6, the valve body 5 and the contact member 6 are moved to an open position where the movable member 4 abuts against the receiving portion 3 g of the main body 3. When the valve body 5 and the contact member 6 move to the open position, the contact member 6 moves away from the valve seat 3e to the downstream side, so that the passage hole 3d is opened. Then, water (hot water) in the upstream portion Ia flows into the downstream portion Ib through the passage hole 3d.

  On the surface facing the upstream side of the contact member 6, an annular groove 6 c is formed that extends annularly about the axis of the contact member 6. The annular groove 6c is disposed so as to be in contact with the inner peripheral portion of the valve portion 6a. The diameter of a circle connecting the center of the annular groove 6c in the width direction (the radial direction of the contact member 6) is set to be substantially the same as the inner diameter of the cylindrical portion 3c. Therefore, both side surfaces of the annular groove 6c straddle the inner peripheral surface of the cylindrical portion 3c in the radial direction of the contact member 6, and the valve body 5 and the contact member 6 are moved to the closed position by the compression coil spring 7. Only the valve portion 6a comes into contact with the valve seat 3e.

  Of the both side surfaces of the annular groove 6c, the radially inner side surface is a contact wall surface 6d. The contact wall surface 6d is inclined so as to be separated from the center of the contact member 6 as it goes from the open portion of the annular groove 6c toward the bottom side, that is, from the upstream side toward the downstream side. Therefore, the outer diameter of each part of the contact wall surface 6d is small on the open side of the annular groove 6c and large on the bottom side. The minimum diameter of the contact wall surface 6d is set smaller than the inner diameter of the cylindrical portion 3c, that is, the inner diameter of the cylindrical wall surface 3f. The maximum diameter of the contact wall surface 6d is set larger than the inner diameter of the cylindrical wall surface 3f. Therefore, the diameter of the abutting wall surface 6d is the same as the inner diameter of the cylindrical wall surface 3f at the intermediate portion in the depth direction of the annular groove 6c (the axial direction of the abutting member 6; the upstream and downstream directions).

  Since the diameter of the end of the contact wall surface 6d on the open side is larger than the inner diameter of the cylindrical wall surface 3f, when the valve body 5 and the contact member 6 are in the closed position as shown in FIG. As shown in FIG. 7, even when a relatively small shock wave (pressure) is applied to the valve body 5, the valve portion 6a only sits on the valve seat 3e, and the contact wall surface 6d It does not hit the cylindrical wall surface 3f.

However, when the pressure of the shock wave acting on the valve body 5 exceeds a predetermined magnitude, the valve portion 6a is largely crushed by the pressure of the shock wave as shown in FIG. It is pushed down to go radially outward. As a result, the valve body 5 and the contact member 6 are moved from the closed position to the upstream side. As a result, a portion of the abutting wall surface 6d on the downstream side of the intermediate portion having the same diameter as the cylindrical wall portion 3f hits a downstream portion of the cylindrical wall surface 3f. As a result, the main body 3 and the contact member 6 are not only pressed and contacted at the valve portion 6a and the valve seat 3e, but are also pressed and contacted at the contact wall surface 6d and the cylindrical wall surface 3f. That is, the number of contact points between the main body 3 and the contact member 6 increases from one place to two places.

In the hot and cold water mixing plug A provided with the check valve 1 having the above-described configuration, it is assumed that the plug valve body is now in the closed position and the hot water and water mixing plug A is not in use. At this time, the valve body 5 and the contact member 6 are urged upstream by the compression coil spring 7 via the movable member 4 and are positioned at the closed position. Therefore, the valve portion 6a is seated on the valve seat 3e, and the mixed water in the downstream portion Ib is prevented from flowing back into the upstream portion Ia through the passage hole 3d.

When the plug valve body is located at the open position and the hot water mixing plug A is in use, the valve body 5 and the contact member 6 resist the biasing force of the compression coil spring 7 by the water (hot water) in the upstream portion Ia. And moved to the open position. As a result, the passage hole 3d is opened, and the water (hot water) in the upstream portion Ia flows into the downstream portion Ib through the passage hole 3d. The mixed water of hot water and hot water mixed in the downstream portion Ib flows out from the water discharge pipe F.

When the hot-water mixing tap A is suddenly changed from the use state to the non-use state, a shock wave is generated in the downstream portion Ib. In this case, when the shock wave is small, the valve portion 6a is slightly crushed as shown in FIG. 7, but the contact wall surface 6d does not contact the cylindrical wall surface 3f. However, when the shock wave exceeds the predetermined magnitude and the upstream pressing force acting on the valve body 5 exceeds the predetermined magnitude, the abutting wall surface 6d hits the cylindrical wall surface 3f as shown in FIG. . As a result, the main body 3 and the contact member 6 are not only pressed and contacted at the valve portion 6a and the valve seat 3e, but are also pressed and contacted at the contact wall surface 6d and the cylindrical wall surface 3f. That is, the number of contact points between the main body 3 and the contact member 6 increases from one place to two places. Therefore, the space between the main body 3 and the contact member 6 can be reliably sealed, and the passage hole 3d can be reliably closed. Therefore, it is possible to prevent the mixed water in the downstream portion Ib from flowing back to the upstream portion Ia through the passage hole 3d.

  Particularly, since the contact wall surface 6d and the cylindrical wall surface 3f are in contact with each other with a certain length in the axial direction of the contact member 6, the valve body 5 and the contact member 6 are prevented from being inclined. When the abutting member is inclined, the contact pressure between the valve seat 3e and the portion of the valve portion 6a located on the most downstream side becomes small, and the mixed water may flow backward therefrom. However, in the check valve 1, the contact wall 6 d and the cylindrical wall surface 3 f come into contact with each other, so that the contact member 6 is prevented from inclining, so that the backflow of mixed water can be prevented. Even if the abutting member 6 is inclined, the abutting wall surface 6d located at the same position in the circumferential direction as the most downstream portion of the valve portion 6a is in contact with the cylindrical wall surface 3f. Pressing contact is made only by the amount of inclination. Therefore, the backflow of mixed water can be prevented more reliably.

  Next, a second embodiment of the present invention will be described. In the second embodiment, only the configuration different from that of the first embodiment will be described, and the same components as those of the first embodiment will be denoted by the same reference numerals and the description thereof will be omitted. To do.

  11 to 15 show a second embodiment of the present invention. In the check valve 1 ′ of this embodiment, an annular protrusion (protrusion) 6 e is formed on the surface facing the upstream side of the contact member 6. The annular protrusion 6e extends annularly in the circumferential direction around the axis of the abutting member 6, and is arranged so that the outer periphery thereof is in contact with the valve portion 6a. The outer peripheral surface of the valve portion 6a is a contact wall surface 6f.

  The abutting wall surface 6f is formed in a taper shape so as to have a smaller diameter from the base end portion toward the distal end portion, that is, toward the upstream side. The outer diameter of the upstream edge of the contact wall portion 6f is set to be smaller than the inner diameter of the cylindrical wall surface 3f. The outer diameter of the downstream edge of the abutting wall portion 6f is set to be equal to or slightly smaller than the inner diameter of the cylindrical wall surface 3f. Therefore, as shown in FIGS. 11 and 14, when the valve portion 6a of the contact member 6 is seated on the valve seat 3e by the compression coil spring 7, the contact wall surface 6f contacts the cylindrical wall surface 3f. There is nothing.

  However, when an upstream pressing force exceeding a predetermined magnitude is applied to the surface facing the downstream side of the valve body 5 by a shock wave, the outer peripheral side portion having the valve portion 6a of the abutting member 6 becomes the disc portion 5a and the valve portion. It is crushed by the seat 3e. Of the crushed portion of the contact member 6, the outer peripheral portion moves to the outer peripheral side of the contact member 6. As a result, as shown in FIG. 15, the outer peripheral surface of the contact member 6 bulges outward. On the other hand, a part of the part on the inner peripheral side of the crushed part is directed obliquely upward in FIG. 14 as shown by an arrow in FIG. 14, and the base end portion of the annular projecting portion 6e has a large diameter. . As a result, the outer diameter of the downstream portion of the abutting wall surface 6f becomes larger than the inner diameter of the cylindrical wall surface 3f, and the abutting wall surface 6f is in press contact with the cylindrical wall surface 3f.

  In the check valve 1 ′ of this embodiment, only the outer protrusion 5 h is formed on the surface facing the downstream side of the disc portion 5 a of the valve body 5, and the inner protrusion 5 i and The radial protrusion 5j is not formed. Therefore, only one circular recess 5k is formed on the surface facing the downstream side of the disk portion 5a. Of course, in this embodiment, the inner ridge 5i and the radial ridge 5j may be formed. Conversely, also in the check valve 1 of the first embodiment, only the outer protrusion 5h may be formed.

  Also in the check valve 1 ′ of the second embodiment, when the pressure exceeds a predetermined magnitude upstream of the shock wave acting on the valve body 5, the contact wall surface 6 f is pressed against the cylindrical wall surface 3 f. Therefore, it is possible to prevent the mixed water in the downstream portion Ib from flowing back into the upstream portion Ia through the passage hole 3d.

In addition, this invention is not limited to said embodiment, A various modification is employable in the range which does not deviate from the summary.
For example, in the above embodiment, the valve body 5 and the abutting member 6 are provided so as to be movable with respect to the main body 3 via the movable member 4, but the movable member 4 is formed integrally with the main body 3, or The valve body 5 and the abutting member 6 may be fixed to the main body 3 so as to be movable in the direction toward the upstream side and the downstream side with respect to the movable member 4. In such a modification, for example, the shaft portion 5b of the valve body 5 is movably inserted into the support cylinder portion 4c of the movable member 4, and the distal end portion of the shaft portion 5b projecting upstream from the support cylinder portion 4c and the movable member. This can be achieved by providing an urging means such as a coil spring for urging the shaft portion 5b to the upstream side between the four support cylinder portions 4c.

DESCRIPTION OF SYMBOLS 1 Check valve 1 'Check valve 3 Main body 3d Passage hole 3e Valve seat 3f Cylindrical wall surface 5 Valve body 6 Contact member 6a Valve part 6c Annular groove 6d Contact wall surface 6e Annular protrusion part (protrusion part)
6f Abutting wall surface 7 Compression coil spring (biasing means)

Claims (5)

A passage hole penetrating the inside is formed, a main body in which a valve seat surrounding the opening of the passage hole is formed on the downstream end surface where the downstream end of the passage hole opens, and an upstream side of the main body A valve body which is provided so as to be movable to the side and the downstream side and which opens and closes the passage hole by being separated and seated with respect to the valve seat, and urges the valve body to the upstream side to be seated on the valve seat A contact member is provided on a surface of the valve body facing the valve seat, the valve body is seated on the valve seat via the contact member, and the contact member Is a check valve composed of an elastic material,
A cylindrical wall surface extending from the downstream end surface toward the upstream side is formed in an annular shape at a portion of the downstream end surface of the main body on the inner peripheral side from the valve seat, and the main body of the contact member A contact wall surface that presses and contacts the cylindrical wall surface over the entire circumference when the upstream pressing force acting on the valve body exceeds a predetermined magnitude is formed in an annular shape on the opposite surface Check valve characterized by. A valve portion seated on the valve seat is formed on a surface of the contact member facing the body, and an annular groove is formed in a portion adjacent to the valve portion of the facing surface on the inner peripheral side. The check valve according to claim 1, wherein the contact wall surface is formed on a side surface on the inner peripheral side of the groove. The abutting wall surface is formed in a tapered shape so as to have a larger diameter toward the downstream side, and the diameter of the abutting wall surface is smaller than the diameter of the cylindrical wall surface at the upstream end, When the acting upstream pressing force exceeds the predetermined magnitude and the valve body and the contact member are moved to the upstream side, the downstream portion of the contact wall surface from the upstream end is The check valve according to claim 2, wherein the diameter of the intermediate portion in the upstream and downstream direction of the abutting wall surface is set to be the same as the diameter of the cylindrical wall surface so as to abut against the cylindrical wall surface. A protruding portion having an outer peripheral surface coaxial with the valve seat is formed in a portion on the inner peripheral side of the valve portion seated on the valve seat in a surface facing the valve body of the contact member. The check valve according to claim 1, wherein the contact wall surface is formed on an outer peripheral surface of the check valve. The diameter of the abutting wall surface at the base end portion of the projecting portion is substantially the same as the diameter of the intersecting portion between the cylindrical wall surface and the downstream end surface of the main body, and the upstream pushing force acting on the valve body is pushed. When the pressure exceeds the predetermined size, the outer peripheral side portion of the contact member pressed against the valve seat is elastically deformed so that a part of the contact member enters between the cylindrical wall surface and the contact wall surface. As a result, the abutting wall surface is in pressure contact with the cylindrical wall surface via the part.

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