JPH031667Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a check valve suitable for installation in a cold water supply system of a hot/cold water mixing faucet.

[Prior Art] In a hot water mixing faucet, hot water supplied from a hot water supply pipe and cold water supplied from a cold water supply pipe flow into a mixing chamber via a mixing valve and can be mixed. As a type of hot water mixing valve, a ceramic disk type valve is used, which includes a pair of ceramic disks that are slidably stacked on top of each other. In this ceramic disk type hot water mixing valve, one fixed ceramic disk is provided with a hot water inlet, a cold water inlet, and a mixed water outlet, and the other movable ceramic disk is provided with a recess that allows these openings to communicate. Set it up,
The movable ceramic disk is slid to change the overlapping area of the recess and each of the openings to adjust the temperature of the mixed water and the amount of outflow.

Therefore, in such a hot water mixing faucet, a check valve is provided in each of the hot water side passage and the cold water side passage to prevent backflow to the hot water supply pipe and the cold water supply pipe.

[Problems to be solved by the invention] As is well known, a check valve only allows flow in the forward direction and has the function of blocking flow in the reverse direction. When a check valve was installed in the cold water side passage of a hot/cold water mixing faucet, the following problems occurred.

In other words, when only hot water is allowed to flow into the mixing chamber after cold water has been passed through the mixing chamber, the cold water passage between the hot water mixing valve and the cold water side check valve becomes sealed. The heat of the hot water is transferred to the cold water passage, causing the cold water to thermally expand. This expansion pressure then acts on the hot water mixing valve, making the movement of the valve body heavier. For example, in a ceramic disk type hot water mixing valve, the ceramic disks press strongly against each other and come into close contact with each other, making it difficult to operate the handle.

[Means for Solving the Problems] The check valve of the present invention includes a cylindrical valve casing having an inlet at one end and an outlet at the other end, and a cylindrical valve casing in the axial direction of the casing. The valve body is mainly composed of a flexible rubber valve body inserted into the valve body so as to be movable forward and backward, and a valve seat member provided on the outlet side of the valve casing.

The flexible rubber valve body has a substantially umbrella-shaped cross-section and has a diameter that allows its outer circumferential surface to come into close contact with the inner circumferential surface of the valve casing. The outer circumference of this valve body is a flexible part whose diameter increases toward the outlet side of the valve casing, and there is a conical protrusion in the center of the face of the valve body on the outlet side. It is formed.

Further, the valve seat member is provided with a cone-shaped seat portion on which the conical protrusion of the valve body is seated, and
A water passage portion is provided around the seat portion to communicate the upstream side and the downstream side of the valve seat member.

[Function] In the check valve of the present invention, when water pressure is applied in the forward flow direction, the peripheral edge of the umbrella-shaped valve body made of flexible rubber deforms in the forward flow direction, and the gap for water passage closes to the inner surface of the casing. It is formed between the two, and water passes through it.

On the other hand, when water flow pressure in the reverse flow direction is applied, the peripheral edge of the valve body comes into close contact with the inner circumferential surface of the casing, preventing reverse flow. Furthermore, in this backflow prevention state, if the pressure on the downstream side of the valve body increases, the valve body retreats upstream while the outer peripheral edge of the valve body remains in close contact with the inner circumferential surface of the casing, and this high pressure on the downstream side decreases. It is possible to achieve this.

[Example] Examples will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a check valve according to an embodiment of the present invention, and FIGS. 2 and 3 are explanatory diagrams of the shape of a valve body. Reference numeral 10 denotes a valve casing, which has a cylindrical shape and has an inlet 12 at one end and an outlet 14 at the other end. A cold water supply pipe 20 is connected to this inlet 12 via a union nut 16 and a joint 18 . Further, a rubber packing 22 is interposed between the end face of the valve casing 10 and the flange portion 18a of the joint 18.

A valve seat member 2 is provided at the outlet 14 of the valve casing 10.
4 is screwed on. The valve seat member 24 includes a ring portion 24a, a seat portion 24b, and a connecting portion 24c that connects the ring portion 24a and the seat portion 24b. The ring portion 24 a has a male thread carved on its outer circumferential surface, and is screwed into a female thread formed on the inner circumferential surface of the valve casing 10 . The seat portion 24b is cone-shaped and narrows toward the outlet side.
A communication hole 24d is formed in the center of the seat portion 24b. The connecting portion 24c is connected to the ring portion 24
It extends in the radial direction from, for example, three directions on the inner circumferential surface of a, and supports the seat portion 24b.

Reference numeral 26 denotes a valve body made of flexible rubber, which has a substantially umbrella-shaped cross-section as shown in FIGS. 2 and 3. That is, a flexible portion 26a whose diameter gradually increases toward the outlet 14 side is formed on its outer peripheral portion, and a chevron-shaped portion 26b that is convex toward the inlet 12 is formed at the center portion on the inlet 12 side. is formed. Also, the back side of this chevron-shaped portion 26b (outflow port 14 side)
is a conical protrusion 26c that can be seated on the cone-shaped seat portion 24b.

In the check valve configured as described above, when water supply pressure is applied from the cold water supply pipe 20, the flexible portion 26a is bent to narrow, and a gap is formed between the flexible portion 26a and the inner peripheral surface of the valve casing 10, etc. is formed and water flows from the inlet 12 to the outlet 14. Conversely, when backflow pressure is applied from the outlet 14 side, the flexible portion 26a
The outer peripheral surface of the valve casing 10 is in close contact with the inner peripheral surface of the valve casing 10,
Prevent backflow. Furthermore, when the pressure downstream of the valve body 26 increases in this backflow prevention state, the valve body 26 retreats toward the inlet 12 while the outer peripheral surface of the flexible portion 26a remains in close contact with the inner peripheral surface of the valve casing 10. It is possible to reduce the pressure on the downstream side.

Therefore, when this check valve is inserted into the cooling water supply system of a hot water mixing faucet, an increase in water pressure in the cold water passage between the check valve and the hot water mixing valve can be avoided, and the hot water mixing An increase in the operating force of the valve is prevented.

Incidentally, although not particularly limited, the angles of each part showing the preferred shape of the valve body used in the present invention are shown in FIG. 3.

[Effects of the invention] As described above, in the check valve of the invention, when the pressure on the downstream side of the valve element increases, the valve element retreats to the upstream side.
The downstream pressure can be reduced.

Therefore, when the check valve of the present invention is installed in the cooling water supply system of a hot and cold water mixing faucet, when switching from the flow of cold water or low-temperature mixed water to the flow of only high-temperature water, the handle will be prevented from becoming heavy. The handle can be operated easily at all times.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a check valve according to an embodiment of the present invention, FIG. 2 is a plan view of a valve body 26, and FIG. 3 is a sectional view taken along the line taken in FIG. 2. 10...Valve casing, 12...Inflow port, 14
...outlet, 24...valve seat member, 26...valve body.

Claims (1)

[Claims for Utility Model Registration] A cylindrical valve casing having an inlet at one end and an outlet at the other end; The valve body includes a flexible rubber valve body whose outer circumferential surface has a diameter that allows it to come into close contact with the inner circumferential surface of a valve casing, and a valve seat member provided on the discharge port side of the valve casing. A flexible portion having a diameter increasing toward the outlet side of the valve casing is formed on the outer peripheral portion thereof, and a conical protrusion is formed in the center of the surface on the outlet side, and the valve seat The member includes a cone-shaped seat portion on which the conical protrusion of the valve body is seated, and a water passage portion provided around the seat portion that communicates the upstream side and the downstream side of the valve seat member. A check valve featuring: