JPH0481673B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention utilizes the difference in specific gravity between gas and liquid to open and close a valve port using a float to automatically discharge one fluid from a gas-liquid mixing system. Regarding valves.

The above float valve is a steam trap that automatically discharges condensate generated in a steam piping system, an air trap that automatically discharges condensed water generated in a compressed air piping system, and an air trap that automatically discharges air mixed in a water piping system. This is an air vent etc. that discharges the air.

The gas with a lower specific gravity is located above the liquid with a higher specific gravity, and the liquid level moves up and down according to changes in the quantitative ratio of the liquid and the gas. The float floats on the liquid surface due to the balance between the buoyant force acting on it and its own weight, and moves up and down with the liquid surface. Float valves take advantage of these natural laws. Gas and liquid are separated in the valve chamber, the valve port is placed at the top or bottom of the valve chamber, and the valve port is opened by the vertical movement of a float housed in the valve chamber. It opens and closes to selectively and automatically discharge one fluid.

<Prior Art> Conventionally, there is a float type trap, for example, as a float valve. This opens the valve port at the bottom of the valve chamber,
This valve port is opened and closed directly on the surface of a float placed freely within the valve chamber. This trap opens and closes one valve opening with one float, and in this case, the area of the valve opening is small and is not suitable for discharging a large amount of fluid.

Patent No. 118910 has a trap that solves this problem. The first valve opening is opened at a lower position in the valve chamber, and the second valve opening is opened at a higher position than the first valve opening. A valve body is provided that opens and closes the first valve port and opens and closes the second valve port directly on the surface of the float, one end of which is connected to the valve body to operate the valve body, and the other end extends above the float. It consists of a lever that is provided so that the float comes into contact with it after opening the valve port.

<Problems to be Solved by the Present Invention> However, when the amount of the trapped liquid is small to medium, the float responds by opening and closing only the first valve port, while the second valve port is constantly in a gas atmosphere. Therefore, the second valve port and the valve body cannot perform a water-sealing action, leading to fluid leakage. If this is a trap for steam, the valve seat forming the valve port and the corresponding float are made of metal, so the sealing performance will be worse. Also,
In the trap described above, a coil spring is provided to close the valve body that opens and closes the second valve port, which has the disadvantage of requiring a large number of parts.

Therefore, a technical object of the present invention is to provide a float valve which is a mechanism having a sub-valve, has a simple structure, and has an excellent valve structure in sealing performance.

<Means for Solving the Problems> The technical means of the present invention taken to solve the above-mentioned technical problems is to form an inlet and an outlet in a valve casing having a valve chamber, and to install a valve at a low position in the valve chamber. A first valve port and a second valve port that communicate with the chamber and the outlet are opened, and a float is housed in a free state in the valve chamber to directly open and close the first valve port by floating up and down according to the liquid level in the valve chamber, A lever equipped with a valve body for opening and closing the second valve port is pivotally connected in the valve chamber, and one end of the lever has a float attached to the first valve.
The second valve port is arranged so as to open the second valve port by contacting the second valve port after opening the valve port, and the second valve port is located at a position lower than the liquid level when the first valve port is completely closed by the float. It is arranged so that it is always submerged in water.

<Effect> The operation of the above technical means is as follows.

The float accommodated in the valve chamber in a free state is displaced up and down along with the liquid level within the valve chamber. When the inflow flow rate is large, the float opens the first valve port and the second valve port via the lever to discharge the liquid. When the flow rate decreases and the liquid level drops, the float opens and closes only the first valve port, does not engage the lever, and closes the second valve port. When the liquid level drops and the first valve port is closed, the second valve port is always below the liquid level and is sealed with water, so that the sealing performance is good and fluid leakage is prevented.

<Example> An example showing a specific example of the above technical means will be described. (See Figures 1 and 2) This embodiment is applied to a closed float type steam trap.

A lid 4 is fastened to the main body 2 with bolts (not shown) to form a valve casing having a valve chamber 6 therein.
A gasket 8 is interposed between the main body 2 and the lid 4 to keep them airtight.

An inlet 10 is formed in the upper part of the lid 4, and an outlet 12 is formed in the lower part. The inlet 10 communicates with the upper part of the valve chamber 6, is connected to steam-using equipment (not shown), etc., and introduces condensate into the valve chamber 6. A first valve seat 16 having a first valve port 14 is provided at the bottom of the main body 2, and a second valve seat 16 is provided at the bottom of the lid 4.
The second valve seats 20 with 8 are respectively screwed together. The first valve port 14 communicates between the valve chamber 6 and the outlet 12 via a communication passage 22 formed in the lower part of the main body 2, and the second valve port 18 directly communicates between the valve chamber 6 and the outlet 12, and condensate is led to outlet 12. The inlet 10 and the outlet 12 open horizontally and each form an internal thread for piping. Each valve seat 16, 20
gasket 16 to ensure airtightness between the corresponding parts
Keep it at a, 20a.

A hollow spherical float 24 made of a thin stainless steel plate is accommodated in the valve chamber 6 in a free state. float 2
4 floats on the condensate accumulated in the valve chamber 6 and rises and falls with the liquid level. The central axis 1 of the first valve port 14 is located on the bottom of the valve chamber 6.
Two protrusions are formed substantially parallel to 4a, and float seats 26a and 26b are formed there. The float seats 26a and 26b are connected to the central axis 14a of the first valve port 14.
are coaxial and formed into a cylindrical surface with a radius slightly larger than the radius of the float 24. As a result, the float seats 26a and 26b can be formed coaxially with the mounting opening (threaded opening) of the first valve seat 16 through a series of machining operations, and there is no need for separate chucking and machining, and the machining is easy. Can be done with high precision.

The second valve seat 20 is installed at a position lower than the liquid level at which the float 24 contacts the valve seat 16 and the float seats 26a, b to completely close the first valve port 14 when the liquid level in the valve chamber decreases.

Attach a lever attachment member (not shown) to the lid 4 with screws. Attach lever 28 to pin 3 on the lever mounting member.
Install with 0. A valve body 32 for opening and closing the second valve port 18 is attached to the lever 28. Therefore, lever 2
8 can rotate using the pin 30 as a fulcrum. Lever 2
The upper part of the float 8 extends diagonally above the float 24 at an angle α from the vertical line. Reference number 34 is float 2
4 in the vertical direction, and are formed at two locations in total, one on the front side of the page, and a slight gap is formed between it and the float 24. In addition, the lever 28
A rib 35 is formed on the side wall inside the valve chamber 6 facing the valve chamber 6 .

Attach the bimetal 36 to the lid 4 with screws 38. The bimetal 36 is approximately U-shaped and expands when the temperature is low, exerting a force that pushes up the lever 28 to open the second valve port 18, and contracts when the temperature is high, causing the lever 28 to open.
Return to a shape that does not involve.

The operation of the steam trap is as follows. The inlet 10 is connected to a location where condensate is generated, such as steam-using equipment. Condensate and steam flow into the valve chamber 6, where the condensate is separated from the lower part and the steam is collected at the upper part. When the amount of condensate flowing in is small, the floating of the float 24 is also small and only the first valve port 14 is opened and closed, and the condensate flows out to the outlet 12 through the first valve port 14 and the communication path 22. When the amount of water condensing into the valve chamber increases, the float 24 rises as the liquid level rises and comes into contact with the lever 28 and the rib 35 on the side wall. When the liquid level further rises, the buoyancy of the float acts on the lever 28 as a wedge force. This wedge force causes the lever 28 to rotate in the valve opening direction (clockwise in FIG. 1) and the valve body 32 to open the second valve opening 1.
Open 8. The condensate in the valve chamber 6 is discharged from the first valve port 14 and at the same time is discharged from the second valve port 18 to the outlet 12.
is discharged.

When the liquid level decreases due to discharge, the float 24 also descends, and as the float descends, the lever 13 rotates in the valve-closing direction, causing the valve body 32 to close the second valve port 18 and close the second valve port 18.
Stop the flow of condensate from the valve port 18. If the liquid level in the valve chamber further decreases, the float 24 descends and the first valve port 14 also closes as shown in FIG. 1, completely stopping the outflow of condensate. At this time, the float seats 26a, b have a cylindrical surface shape slightly larger than the radius of the float 24 in the circumferential direction, and are formed in two strips parallel to the central axis 14a of the first valve port 14.
The float 24 that has descended comes into contact with the float seats 26a and 26b, and at the same time is seated on the first valve seat 16, completely closing the first valve port 14.

Further, as shown in FIG.
Since the valve port 18 is located at a position lower than the liquid level 40 when the float 24 completely closes the first valve port 14, it is constantly submerged in water and its water sealing action protects the valve body 32 and the second valve seat 20. This improves the sealing performance and prevents leakage of condensate and steam.

<Effects of the invention> The present invention produces the following unique effects.

Since a sub-valve is used, the amount of condensate discharged is increased, and since the second valve port is always submerged in water, its water-sealing effect greatly improves the sealing performance between the valve body and the valve seat. Further, unlike the conventional method, a coil spring for opening the second valve port is not required, and the structure is simple and the number of parts is reduced.

In addition, the condensate discharged from the first valve port causes the second
Since the pressure on the secondary side of the valve port increases, the pressure difference acting on the second valve port becomes smaller. Therefore, the second valve port can be opened and closed with a small operating force, or the valve port can be designed to be larger accordingly, so that the discharge flow rate can be further increased.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a sealed float type steam trap according to an embodiment of the float valve of the present invention, and FIG. 2 is a partial plan sectional view of the first valve seat portion of FIG. 1. 2...Main body, 4...Lid, 6...Valve chamber, 10...
Inlet, 12... Outlet, 14... First valve port, 18...
...Second valve port, 24...Float, 28...Lever.

Claims (1)

[Claims] 1 An inlet and an outlet are formed in a valve casing having a valve chamber, and a first
A valve that opens a valve port and a second valve port, and houses a float in a free state in the valve chamber that floats up and down according to the liquid level in the valve chamber to directly open and close the first valve port, and opens and closes the second valve port. A lever with a body attached thereto is pivotally coupled within the valve chamber, one end of the lever is arranged so as to abut after the float opens the first valve port to open the second valve port, and the second valve port is A float valve characterized in that the float is arranged so as to be constantly submerged in water at a position lower than the liquid level with the first valve port completely closed.