JPH07167390A - Float valve - Google Patents

Abstract

PURPOSE:To prevent magnetization due to frictional contact action to cause the adhesion of foreign matter such as iron powder by forming at least the small diameter hole formed part of a valve seat member of ceramic material. CONSTITUTION:An inlet 5 and an outlet 6 are coaxially opened at the upper part of a body 1. The inlet 5 is communicated with a valve chamber 4 through a cylindrical screen 7, and the outlet 6 is communicated with the valve chamber 4 through a valve seat member 8. The valve seat member 8 fitted to the lower part side wall of the body 1 is formed of a base part 9 screw-connected to the body 1 and a tip part 10 shrinkage-fitted to the base part 9. The base part 9 is formed of stainless steel, and the tip part 10 is formed of ceramic material. The valve seat member 8 has a valve hole 11 opened to communicate the valve chamber 4 with the outlet 6 side, and a hollow spherical float 16 is disposed in the free state at the valve chamber 4. The tip part 10 formed of ceramic material is not magnetized even if a discharge fluid flows down at high speed in a small diameter hole 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention utilizes a difference in specific gravity between gas and liquid to drive valve means by an open or closed float to automatically discharge one fluid from a gas-liquid mixing system. Regarding the structure of the float valve.

This float valve is used to selectively and automatically discharge either gas or liquid from a system in which gas and liquid coexist, and automatically condenses water generated in a steam piping system. Steam trap, which discharges condensed water generated in the compressed air piping system,
It is used as an air vent that automatically discharges the air mixed in the water piping system.

In the above-mentioned float valve, the float floating on the liquid surface moves up and down together with the liquid surface due to the balance between buoyancy and its own weight, thereby driving the valve means to open and close the valve hole formed in the valve seat member. Therefore, the area of the valve hole that can be opened and closed is limited, and the valve chamber side is formed as a small diameter hole having a relatively small diameter.

[0004]

2. Description of the Related Art A float valve having a valve seat structure as described above is disclosed, for example, in Japanese Patent Publication No. 59-32718. The float valve disclosed here is a free-float trap, and as understood from the publication, a large-diameter hole having a larger cross-sectional area than the small-diameter hole on the valve chamber side and the small-diameter hole on the downstream side. The valve seat member having a valve hole made of is made of stainless steel which is a metal material harder than the valve casing in consideration of wear resistance. Further, it has been conventionally performed to subject this valve seat member to a quenching treatment to further improve its hardness.

[0005]

However, the above-mentioned conventional device has a problem that the flow passage area of the small diameter hole is reduced in a relatively short time and a desired discharge flow rate cannot be obtained. This is because foreign matter such as iron powder and carbon mixed in the discharged fluid adheres to and accumulates in the small diameter holes. That is, the inside of the small-diameter hole of the valve seat member made of stainless steel is magnetized by the frictional action because the discharged fluid flows down at a high speed, and iron powder adheres to the inside of the small-diameter hole. Foreign matter is accumulated.

Therefore, a technical object of the present invention is to obtain a float valve in which foreign matter does not adhere to the small diameter hole of the valve hole.

[0007]

The technical means of the present invention taken to solve the above technical problems is to form an inlet, a valve chamber and an outlet by valve casing, and to form a small diameter hole on the valve chamber side. A float that connects the valve chamber to the outlet side by a valve seat member having a valve hole having a valve hole, and drives the valve means by a float arranged in the valve chamber to open and close the valve chamber side opening end of the small diameter hole. In the valve, at least a portion of the valve seat member forming the small diameter hole is made of a ceramic material.

Alumina, silicon nitride, zirconia or the like can be used as the above ceramic material.

[0009]

The operation of the above technical means is as follows.
Since the portion forming the small diameter hole of the valve seat member is made of a ceramic material, the discharged fluid is not magnetized even when flowing down through the small diameter hole at a high speed. Therefore, iron powder or the like does not adhere, and the foreign matter flows off to the downstream side together with the discharged fluid flowing down at a high speed.

[0010]

EXAMPLE An example showing a concrete example of the above technical means will be described (see FIG. 1). This embodiment is applied to a free-float steam trap. Main body 1 and lid member 2
Are fastened with bolts 3 to form a valve casing, and a valve chamber 4 is formed inside. The main body 1 has an inlet 5 and an outlet 6 on the same axis at the top. The inlet 5 communicates with the valve chamber 4 via a cylindrical screen 7. The outlet 6 communicates with the valve chamber 4 via a valve seat member 8 described below.

The valve seat member 8 is screwed and attached to the lower side wall of the main body 1. The valve seat member 8 includes a base portion 9 that is screwed to the main body 1, and a tip portion 10 that is attached to the tip portion of the base portion 9 by shrink fitting. The base portion 9 is made of stainless steel, and the tip portion 10 is made of a ceramic material. The valve seat member 8 is formed with a valve hole 11 that allows the valve chamber 4 to communicate with the outlet 6 side. The valve hole 11 includes a large-diameter hole 12 formed in the base portion 9, a through-hole 13 for communicating the large-diameter hole 12 with the outlet 6 side, a small-diameter hole 14 formed in the valve chamber 4 side of the tip portion 10, The taper hole 15 connects the small diameter hole 14 to the large diameter hole 12 of the base 9.

Inside the valve chamber 4, a hollow, spherical float 16 is arranged in a free state. A float seat 17 is formed at the bottom of the valve chamber 4 to define the descending position of the float 16.

Condensate flowing from the inlet 5 is accumulated in the valve chamber 4,
The float 17 floats and descends according to the liquid level to open and close the end of the small diameter hole 14 on the valve chamber 4 side. As a result, the condensed water in the valve chamber 4 is discharged from the valve hole 11 to the outlet 6. The tip portion 10 made of a ceramic material does not magnetize even if the discharged fluid flows down through the small-diameter hole 14 at a high speed, so that iron powder or the like does not adhere to the foreign matter and the foreign matter exits with the discharged fluid flowing down at a high speed. Run off to 6.

In the above embodiment, the base portion and the tip end portion of the valve seat member are joined by shrink fitting, but
They may be connected by screw connection or other means. Although only the tip of the valve seat member is made of a ceramic material, the entire valve seat member may be made of a ceramic material.

[0015]

The present invention produces the following unique effects. As described above, according to the present invention, since foreign matter does not adhere and accumulate in the small diameter hole made of the ceramic material, the discharge flow rate does not decrease.
It is possible to obtain a float valve capable of maintaining a good initial discharge action over a long period of time. Further, since the ceramic material does not cause rusting, this also prevents foreign matter from adhering and depositing in the small diameter holes. Furthermore, since the ceramic material has a high hardness, it is possible to prevent the end of the small diameter hole on the valve chamber side from being worn away by frequent seating of the valve means, and maintain a good initial sealing action for a long period of time. You get a float valve that you can.

[Brief description of drawings]

FIG. 1 is a sectional view of a free float type steam trap of an embodiment of a float valve of the present invention.

[Explanation of symbols]

 1 Main body 2 Lid member 4 Valve chamber 5 Inlet 6 Outlet 8 Valve seat member 9 Base part 10 Tip part 11 Valve hole 12 Large diameter hole 14 Small diameter hole 16 Float

Claims (1)

[Claims] 1. A valve seat is provided with a valve seat member having an inlet, a valve chamber and an outlet formed by valve casing, and having a valve hole having a small diameter hole formed on the valve chamber side so that the valve chamber communicates with the outlet side. In the one in which the valve means is driven by the arranged float to open and close the opening end on the valve chamber side of the small diameter hole, at least the portion forming the small diameter hole of the valve seat member is made of a ceramic material. valve.