JP2673749B2 - Temperature responsive valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention operates a valve body with a reversal bimetal that is heated and cooled by a controlled fluid and deforms from one shape to another in a snap action, so that fluid above or below a predetermined temperature is automatically operated. Related to a temperature responsive valve for exhausting the gas.
This temperature responsive valve is used as a steam trap that discharges condensate generated in the steam system, an antifreeze valve that opens and leaks water immediately before freezing so that the water pipe does not freeze.

In the valve using the reversal bimetal, there is a large difference in the temperature of the controlled fluid between when the reversal bimetal is opened and when the reversal bimetal is closed due to the fluid pressure acting on the valve body when the valve is closed. There was a problem.

[0003]

2. Description of the Related Art Therefore, in the prior art, Japanese Patent Laid-Open No. 55-7296 has been proposed.
The technique shown in Japanese Patent No. 9 was used. This forms an inlet, a valve chamber, and an outlet by valve casing, forms a valve port that communicates the valve chamber with the outlet, arranges an inverted bimetal in the valve chamber, and opens and closes the valve port in the center of the inverted bimetal. When the valve body is fixed and the shape of the reversal bimetal is displacing the valve body to the closed position, a spring is provided to apply a force to the reversal bimetal so as to deform it to another shape.

Since the spring exerts a force on the reversal bimetal in the direction opposite to the fluid pressure that acts when the valve body closes the valve opening, the difference between the on-off valve temperatures can be reduced.

[0005]

In the above, the spring always acts in the direction opposite to the fluid pressure in the closed state, so that a strong spring can be used to close the valve in a low-pressure piping system. On the other hand, if a weak spring is used, the difference in the on-off valve temperature does not shrink very much in the high-pressure piping system.

Therefore, a technical object of the present invention is to make it possible to reduce the difference in on-off valve temperature regardless of the pressure of the piping system.

[0007]

The technical means of the present invention taken to solve the above technical problem is to form an inlet, a valve chamber and an outlet by valve casing, and to communicate the valve chamber with the outlet. A valve opening is formed, a reversing bimetal is placed in the valve chamber, and the valve body that opens and closes the valve opening is fixed in the center of the reversing bimetal. A curved bimetal that is deformed in proportion to is arranged, the bending direction of the curved bimetal is formed in the same direction as the direction in which the inverted bimetal should be inverted due to temperature change, and the center of the curved bimetal is overlapped with the inverted bimetal to form a valve body. It is fixed to.

[0008]

The operation of the above technical means is as follows.
Since the bending direction of the bending bimetal is formed in the same direction as the direction in which the reversing bimetal should be reversed due to temperature change, the temperature in the valve opening direction changes from the shape in which the reversing bimetal displaces the valve body to the valve closing position. When changed, the curved bimetal bends in the same direction as the direction in which the inverted bimetal should be inverted, and the bending force acts on the inverted bimetal to try to invert the inverted bimetal. Then, when the temperature reaches almost the same temperature as the valve closing temperature, the reverse bimetal reverses and opens. The curved bimetal exerts a bending force on the reversal bimetal in proportion to the change of the fluid temperature regardless of the pressure of the piping system, so that the difference in the on-off valve temperature can be reduced regardless of the fluid pressure.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment showing a specific example of the above technical means will be described (see FIGS. 1 to 3). In this embodiment, a temperature responsive valve is applied to the exhaust valve of the steam trap. A lid 2 is fastened to the main body 1 with bolts 3 to form a valve casing, and a valve chamber 4 is formed inside. The inlet 5 is opened in the upper part of the valve chamber 4. The inlet 5 communicates with the valve chamber 4 via a cylindrical screen 6. An outlet 7 is formed on the same axis as the inlet 5.

A trap valve seat 8 is attached to the bottom of the main body 1. The trap valve seat 8 maintains an airtightness with the main body 1 by an O-ring 9 provided on the outer circumference, and a plug 10 screw-connected to the main body
Hold with. The trap valve seat 8 is formed with a trap valve opening 11 opening at the inner end of the valve chamber 4, an axial trap valve hole 12, and a through hole 14 positioned in the direction of the rising passage 13.
The valve chamber 4 has an outlet 7 through a trap valve opening 11 of the trap valve seat 8, a trap valve hole 12, a through hole 14 and a rising passage 13.
Communicate with

A hollow spherical float 15 is accommodated in the valve chamber 4 in a free state. A float cover 16 that holds the float 15 is attached above the float 15. The front cover 16 has many through holes. A float seat 17 that defines the descending position of the float 15 is formed in the lower portion of the valve chamber 4.

An annular wall 18 is formed on the inner wall of the lid 2, a holding member 20 is fixed via a snap ring 19, and a bimetal chamber 21 is formed inside. The holding member 20 has a communication hole 2
2 is formed, and a screen 23 is attached to the lower surface. A passage 24 that connects the upper portion of the lid 2 and the main body 1 to the upper portion of the valve chamber 4 and the outlet 7 is formed. A valve seat 25 is attached to the inner end of the valve chamber 4 of the passage 24. A valve opening 26 is formed in the valve seat 25.

In the bimetal chamber 21, there are arranged a disk-shaped inverted bimetal 27 and a disk-shaped curved bimetal 28 which deforms in proportion to temperature changes. Inverted bimetal 27
A valve element 29 for opening and closing the valve opening 26 is attached to the center of the curved bimetal 28 with a snap ring 30. The valve body 29 has a mushroom shape, and the inverted bimetal 27 and the curved bimetal 28 are tightly fixed between the umbrella portion and the snap ring 30. A rib is provided on the inner peripheral surface of the annular wall 18 to form a stopper for restricting the upward movement of the reversal bimetal 27, and a stopper for restricting the downward movement is formed on the outer peripheral upper surface of the holding member 20.

When the temperature inside the valve chamber 4 is low, as shown in FIGS. 1 and 2, the inverted bimetal 27 is curved downwardly in a convex shape, and the curved bimetal 28 is flat. The outer peripheral upper surface of the reversal bimetal 27 contacts the stopper 30, and the upward movement is restricted,
The valve body 29 opens the valve opening 26 and discharges low temperature air.

When the temperature inside the valve chamber 4 gradually rises due to the discharge of the low temperature air, the curved bimetal 28 is deformed in an upward convex shape, and when the desired temperature is reached, the reversal bimetal 27 is deformed. Invert, and as shown in FIG. 3, invert upward. The valve body 29 closes the valve opening 26 to prevent fluid from flowing out. At this time, the curved shapes of the inverted bimetal 27 and the curved bimetal 28 are almost the same.

When the temperature in the valve chamber 4 gradually decreases, the curved bimetal 28 has the shape shown in FIG.
Although it gradually tries to return to a flat shape, it cannot be deformed by the inverted bimetal 27 until the desired temperature is reached.
At this time, the outer peripheral portion of the curved bimetal 28 is located above the lower surface of the inverted bimetal 27, and the inner peripheral portion thereof is the snap ring 3.
It exerts a force to displace 0 downward. And
When the desired temperature is reached, the reverse bimetal reverses,
And the shape shown in FIG.

[0017]

The present invention has the following specific effects. As described above, according to the present invention, it is possible to obtain a temperature responsive valve capable of opening and closing at substantially the same temperature regardless of the pressure of the piping system.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment in which a temperature responsive valve of the present invention is applied to an exhaust valve of a steam trap.

FIG. 2 is an enlarged sectional view showing a valve open state of a valve body portion of FIG.

FIG. 3 is an enlarged cross-sectional view showing a valve closed state of the valve body portion of FIG.

[Explanation of symbols]

 1 Main Body 2 Lid 4 Valve Chamber 5 Inlet 7 Outlet 11 Trap Valve Port 15 Float 21 Bimetal Chamber 25 Valve Seat 26 Valve Port 27 Inverted Bimetal 28 Curved Bimetal 29 Valve Body

Claims (1)

(57) [Claims] 1. An inlet, a valve chamber, and an outlet are formed by valve casing, a valve port is formed to connect the valve chamber to the outlet, a reversing bimetal is arranged in the valve chamber, and a valve port is formed at the center of the reversing bimetal. In a fixed valve body that opens and closes, a curved bimetal that deforms in proportion to the temperature change is arranged on the surface of the reversing bimetal opposite to the valve port, and the bending direction of the curved bimetal changes depending on the temperature change. A temperature-responsive valve that is formed in the same direction as the reverse bimetal to be reversed, and the center of the curved bimetal is superimposed on the reverse bimetal and fixed to the valve body.