JPH0743076B2 - Float valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a float valve for automatically discharging a liquid from a gas-liquid mixing system by using a difference in specific gravity between a gas and a liquid to open and close a valve port with the float. .

The float valve is a steam trap that automatically discharges condensed water generated in the piping system, an air trap that automatically discharges condensed water generated in the compressed air piping system, and the like.

A gas with a small specific gravity is located above a liquid with a large specific gravity,
The liquid surface moves up and down according to the change in the quantitative ratio of liquid and gas. The float floats on the liquid surface by the balance between the buoyancy acting on it and its own weight, and moves up and down together with the liquid surface. Float valves use these natural laws.The gas-liquid is separated in the valve chamber, the valve port is arranged at the bottom of the valve chamber, and the valve port is opened and closed by the vertical movement of the float accommodated in the valve chamber. The liquid is selectively and automatically discharged.

<Prior Art> As a float valve, for example, there is a float type trap. This opens a valve opening in the lower part of the valve chamber, and directly opens and closes this valve opening on the surface of the float arranged in the valve chamber in a free state. This trap opens and closes one valve opening with one float, the area of the valve opening is small, and it was not suitable for discharging a large amount of fluid.

As a trap for solving this, there is a trap disclosed in Japanese Patent Publication No. 57-8358. This opens the first valve opening in the low position of the valve chamber, opens the second valve opening in the valve chamber higher than the first valve opening, and is placed in the valve chamber and floats down according to the liquid level in the valve chamber. A valve body for directly opening and closing the first valve opening and for opening and closing the second valve opening is provided on the surface of the float, and one end is connected to the valve body to operate the valve body and the other end extends above the float. The lever is provided so that the float after opening the valve opening comes into contact with the float.

<Problems to be Solved by the Present Invention> However, although the trap has two valve openings, there is a problem that the desired discharge flow rate cannot be obtained. This is because the second valve opening is at a high position, and there is a portion where the conduit resistance such as a bend increases while communicating with the outlet.
This is because the desired flow rate does not flow even when the valve port is fully opened. Further, providing the valve opening at a high position in the valve chamber means that the valve opening exists in the gas atmosphere, and therefore, the water sealing action cannot be performed, which leads to gas leakage. If this is a trap for steam, the sealability will be worse because the floats corresponding to the valve seat forming the valve opening are metal. Further, in the above-mentioned trap, a coil spring is provided to close the valve body that opens and closes the second valve opening, and there is a problem that the number of parts is increased.

Therefore, the technical problem of the present invention is a float valve having two valve openings, which has a simple structure and less gas leakage,
The purpose of the present invention is to provide a float valve with which a desired discharge flow rate can be obtained.

<Means for Solving the Problem> The technical means of the present invention taken to solve the above technical problem is to form an inlet and an outlet in a valve casing having a valve chamber, and to form the valve chamber at the lower part of the valve chamber. A first valve opening and a second valve opening communicating with the outlet through the discharge passage, and a float that floats and descends according to the liquid level in the valve chamber is accommodated in the valve chamber in a free state,
The second valve opening is arranged above the first valve opening and
The valve opening is provided at a position lower than the liquid surface in the state where the float closes the first valve opening, and the first valve opening is opened and closed directly on the outer surface of the float, and the valve body for opening and closing the second valve opening is attached. The lever is pivotally connected to the valve chamber, and one end of the lever is arranged so that the float opens the first valve opening and then abuts to open the second valve opening. The discharge passage for the valve opening is formed by a smooth pipe passage so that the pipe resistance is reduced.

<Operation> The float accommodated freely in the valve chamber moves up and down together with the liquid level in the valve chamber. When the inflow rate is high, the float opens the first valve opening and the second valve opening via the lever to discharge the fluid. In this case, both the first valve opening and the second valve opening are located in the lower part of the valve chamber, and a smooth discharge flow path is formed between the first valve opening and the second valve opening, so that the conduit resistance is reduced.

<Example> An example showing a specific example of the above technical means will be described.
(See FIG. 1) This embodiment is applied to a closed float type steam trap.

A lid 2 is fastened to the main body 1 with bolts 3 to form a valve casing having a valve chamber 4 inside. A gasket 5 is interposed between the main body 1 and the lid 2 to keep them airtight.

An inlet 6 is formed in the upper part of the body 1 and an outlet 7 is formed in the lower part. The inlet 6 communicates with the upper portion of the valve chamber 4 and is connected to a steam-using device (not shown) or the like to introduce condensed water into the valve chamber 4. Body 1
A first valve seat 16 having a first valve opening 14 at the bottom of the
The second valve seat 20 having the valve port 18 is provided with gaskets 15 and 19 respectively.
Screwed through. The first valve opening 14 and the second valve opening 18 communicate the valve chamber 4 and the outlet 7 through the discharge passage 22 formed in the main body 1, and guide the condensed water of the valve chamber 4 to the outlet 7. The discharge passage 22 is a single common passage, and is formed in a shape that eliminates bent portions and narrowed portions as much as possible. Inlet 6 and outlet 7 open horizontally
Each has a female thread for piping.

A hollow spherical float 8 made of a stainless steel thin plate is accommodated in the valve chamber 4 in a free state. The float 8 floats on the condensed water accumulated in the valve chamber 4 and ascends and descends together with the liquid surface. Two protrusions are formed on the bottom surface of the valve chamber 4 substantially parallel to the central axis of the first valve opening 14,
The float seat 26 is formed.

Attach a lever attachment member (not shown) to the main body 1 with a screw. Attach the lever 28 with the pin 30 to the lever attachment member. A valve body 32 for opening and closing the second valve opening 18 is attached to the lever 28. Therefore, the lever 28 can rotate about the pin 30 as a fulcrum. lever
The upper portion of the lever 28 extends obliquely above the float 8 at an angle α from the vertical line, and the upper portion of the lever 28 at an angle β from the vertical line.

The gasket 5 between the main body 1 and the lid 2 is formed of Teflon or the like, and is also present on the inner wall portion in the valve chamber 4, so that the float 8 abuts on the opposite side when moving upward while abutting on the lever 28. The frictional resistance of the part should be small.

The operation of the steam trap is as follows. Entrance 6
Is connected to the condensate generation place such as steam-using equipment. Condensate and steam flow into the valve chamber 4, and condensate is separated into a lower part and steam is separated into an upper part and accumulated. When the amount of condensate inflow is small, the float 8 floats little and only the first valve port 14 is opened and closed, and the condensate flows out to the outlet 7 through the first valve port 14 and the discharge passage 22. If the amount of condensed water in the valve chamber increases, the float 8 floats as the liquid level rises and contacts the lever 28 and the gasket 5 on the inner wall of the casing. Further, the buoyancy of the float 8 that raises the liquid level acts on the lever 28 as a wedge force. This wedge force causes the lever 28 to rotate in the valve opening direction (clockwise direction in FIG. 1) and the valve element 32 to move to the second valve opening.
Open 18 Condensate in the valve chamber 4 is discharged from the first valve opening 14 and at the same time is discharged from the second valve opening 18 to the outlet 7. At this time, since the first valve opening 14 and the second valve opening 18 communicate with the outlet 7 through the common discharge passage 22, and the discharge passage 22 is formed smoothly, the pipe resistance is small. Will be things.

When the liquid level drops due to discharge, the float 8 also descends, and as the float 8 descends, the lever 28 rotates in the valve closing direction and the valve body 32
Closes the second valve opening 18 and stops the outflow of condensed water from the second valve opening 18. When the liquid level in the valve chamber 4 further lowers, the float 8 descends and the first valve port 14 is also closed to completely stop the condensate outflow as in the state shown in FIG. At this time, since the float seat 26 is formed with two threads in parallel with the central axis of the first valve opening 14,
The descended float 8 contacts the float seat 26 and at the same time sits on the first valve seat 16 to completely close the first valve port 14.

Further, the second valve opening 18 of the second valve seat 20 is provided so that the float 8 is located at a position lower than the liquid level in the state where the first valve opening 14 is completely closed, so that the water is always submerged and Due to the sealing action, the sealing property between the valve element 32 and the second valve seat 20 is improved and the leakage of steam is prevented.

<Effects of the Invention> Since the first valve opening and the second valve opening are adopted, the amount of condensate discharged increases, and in addition, the conduit resistance in the discharge path leading from both valve openings to the outlet is small, and the loss is small. As a result, a desired sufficient discharge flow rate can be obtained. Also,
Both the first and second valve openings are always submerged,
The valve mouth and the outer surface of the float are in contact with each other in water to close the valve mouth, and the outer circumference of the contact surface between the valve mouth and the outer surface of the float is in a water-sealed state so that the vaporous vapor is not leaked.
That is, due to the water sealing action, the sealing property between the outer surface of the float as the valve body and the valve seat having the valve opening is greatly improved. Further, unlike the conventional case, a coil spring for closing the second valve port is not required, and the structure is simple and the number of parts is reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of a closed float type steam trap of an embodiment of the float valve of the present invention. 1: Main body, 2: Lid 4: Valve chamber, 6: Inlet 7: Outlet, 8: Float 14: First valve port, 16: First valve seat 18: Second valve port, 20: Second valve seat 22: Discharge path, 28: lever

Claims (1)

[Claims] 1. A valve casing having a valve chamber having an inlet and an outlet formed therein, and a first valve opening and a second valve opening, which communicate the valve chamber and the outlet through a discharge passage, are formed in a lower portion of the valve chamber, and a valve is formed. A float that floats and descends according to the liquid level in the chamber is accommodated in the valve chamber in a free state, and the second valve port is arranged above the first valve port,
The second valve opening is provided at a position lower than the liquid surface in a state where the float closes the first valve opening, and the first valve opening opens and closes directly on the outer surface of the float to open and close the second valve opening. The lever having the valve attached thereto is pivotally connected to the valve chamber, and one end of the lever is arranged so that the float abuts the valve after opening the first valve opening to open the second valve opening. And a discharge valve for the second valve port, which is formed by a smooth conduit so that the conduit resistance is reduced.