JP3273346B2 - Temperature sensing valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature sensing valve for discharging a fluid having a predetermined temperature or higher to the outside of a valve by opening and closing a valve body by sensing the temperature of a fluid passing through the inside of the valve.

[0002]

2. Description of the Related Art As a conventional temperature sensing valve, for example,
There is one disclosed in Japanese Patent Application Laid-Open No. 1-103030. this is,
By using a temperature-sensitive magnetic material made of ferrite as a temperature-sensitive element, when the temperature of the temperature-sensitive magnetic material is lower than a predetermined temperature, the air communication port is opened by the magnetic force of the temperature-sensitive magnetic material, and the air is sucked in. When the temperature exceeds the temperature, the magnetic force of the temperature-sensitive magnetic body is lost and the valve body is displaced, thereby closing the atmosphere communication port and opening the negative pressure valve port, and opening and closing the valve port at a predetermined temperature as a boundary. is there.

[0003]

In the above-mentioned prior art, there is a problem that a so-called chattering phenomenon occurs in which the valve body causes a remarkable vibration immediately after the opening of the valve port. This is because, immediately after the valve element is opened, the speed of the fluid around the valve element rapidly increases and the static pressure decreases, so that the valve element is sucked in the valve closing direction to close the valve. The valve is opened by the heating element, and the valve element exhibits a vibration state by repeating this operation.
The vibration of the valve body causes the wear of the valve part to progress, and when the vibration becomes severe, the valve part may be damaged.

Accordingly, it is an object of the present invention to provide a thermosensitive valve in which the valve body does not vibrate even immediately after the valve body is opened.

[0005]

The construction of the temperature sensing valve of the present invention is as follows. An inlet and an outlet are formed in the valve casing, and a valve body and a valve port that define the inlet and the outlet are arranged to face each other,
A piston portion is connected to the end of the valve body, a cylinder portion is formed by valve casing on the outer periphery of the piston portion, and a substantially cylindrical bellows is attached to one surface of the piston portion. The piston, the piston, and the cylinder are provided with expansion medium reservoirs on both surfaces of the piston to vary the pressure receiving areas of the expansion media on both surfaces of the piston, and the piston is provided with pores communicating with the expansion medium reservoirs on both surfaces. The bellows outer peripheral space is connected to an inlet of a valve casing.

[0006]

By connecting the inlet of the valve casing and the outer peripheral space of the bellows, when the fluid temperature on the inlet side rises, the bellows temperature also rises and the internal expansion medium thermally expands. The expansion of the expansion medium on the bellows side is transmitted through the pores of the piston to the expansion medium reservoir on the opposite side of the piston, so that the expansion medium on both sides of the piston has the same pressure. By making the expansion medium pressure receiving area on both sides of the piston different, the piston and valve element are displaced in the valve opening direction by increasing the pressure receiving area on the piston surface in the valve opening direction of the valve element, and the valve port is opened. Connect the inlet and outlet.

The piston is connected to the end of the valve body, and the expansion medium reservoir is provided on both sides of the piston through a fine hole, so that the displacement of the valve body moves the expansion medium through the fine hole. Is limited to only the displacement according to. By making the effective cross-sectional area of the pores sufficiently smaller than the expansion medium pressure receiving area of the piston portion, the movement of the expansion medium, that is, the displacement of the valve element can be delayed, and the high-speed fluid immediately after the valve element opens. Therefore, even if the static pressure is reduced, the instantaneous displacement of the valve body due to the reduction can be prevented, and therefore, the vibration of the valve body, that is, the chattering phenomenon can be prevented.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. The main body 1 and the lid 2 form a valve casing, and the main body 1 has an inlet 3 and a valve port 4.
And an outlet 5 are formed. A disc-shaped valve element 6 is disposed opposite to the valve port 4 to define the inlet 3 and the outlet 5. A piston 8 is integrally formed above the valve body 6 via a connecting rod 7. The piston 8 has a cylindrical shape and a small-diameter metal bellows 9 having a small diameter is attached to the upper portion of the piston 8 by welding, and the expansion medium reservoir 1 is provided inside.
0 is provided. The outer peripheral chamber 18 of the metal bellows 9 has a communication passage 17.
In addition, an adjusting screw 20 which can be moved up and down in the vertical direction is arranged at the upper end of the metal bellows 9 while being connected to the inlet 3. The displacement of the bellows 9 can be adjusted by moving the adjusting screw 20 forward and backward. A large-diameter cylindrical space having the same diameter as the piston 8 is formed below the piston 8 to form another expansion medium reservoir 11. The expansion medium reservoirs 10 and 11 communicate with each other by a small hole 19 penetrating the piston 8.

A lower end of the expansion medium reservoir 11 is partitioned from the outlet 5 by a partition plate 12 and a coil spring 1 for urging the valve body 6 between the lower surface of the partition plate 12 and the upper surface of the valve body 6 in the valve closing direction.
Place 3. A sliding ring 1 is provided at the center of the partition plate 12.
4 is attached, and the connecting rod 7 is slidably penetrated.

The expansion medium may be a liquid medium whose volume is expanded or a gas medium whose volume is expanded as a gas.

Next, the operation will be described. The fluid at the inlet 3 passes through the communication passage 17 and reaches the outer peripheral chamber 18 of the bellows 9. As the temperature of the fluid increases, the expansion medium 10 in the bellows 9 expands, and the expansion medium 11 expands through the pores 19. When the fluid temperature exceeds a predetermined value and the expansion amount of the expansion medium also reaches a predetermined amount, the piston 8 overcomes the urging force of the coil spring 13 and is displaced upward, so that the valve body 6 is also opened. That is, since the pressure receiving area of the expansion medium reservoir 10 above the piston 8 is made smaller than the lower surface, even if the pressure of the expansion medium acting on the upper and lower surfaces of the piston 8 is the same, the piston 8 moves upward due to the difference in the pressure receiving area. Is displaced. By opening the valve body 6, the fluid having a predetermined temperature or higher on the inlet 3 side flows down to the outlet 5 side.

When the valve 6 opens and the fluid flows down from the lower surface of the valve 6 to the outlet 5 at a high speed, the static pressure on the lower surface of the valve 6 decreases in proportion to the flow velocity and the valve 6 is closed. An effect of sucking downward is generated. However, the displacement of the piston 8 provided integrally with the valve body 6 is buffered and substantially restricted by the movement of the expansion media 10 and 11 through the small holes 19, and the displacement of the valve body 6 is delayed. Therefore, the degree of displacement due to the downward suction action becomes extremely small, and therefore, the vibration state of the valve body 6, that is, the chattering phenomenon can be prevented.

When the fluid temperature of the outer peripheral chamber 18 of the bellows 9 decreases, the expansion medium inside the bellows 9 and the lower surface of the piston 8 also contracts, and the piston 8 and the valve body 6 move downward by the urging force of the coil spring 13. And the valve port 4 is closed.

[0014]

The present invention has the following effects. The instantaneous displacement of the valve element due to the decrease in the static pressure of the high-speed fluid can be prevented by the buffering effect of the expansion medium by the pores provided in the piston, and a significant vibration state of the valve element, that is, the chattering phenomenon, is prevented. It is possible to obtain a temperature-sensitive valve that does not cause wear or damage of the part.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of a temperature sensing valve of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 2 Lid 3 Inlet 4 Valve port 5 Outlet 8 Piston 9 Bellows 10, 11 Expansion medium reservoir 17 Communication passage 19 Micropore

Claims (1)

(57) [Claims] 1. An inlet and an outlet are formed in a valve casing, and a valve body and a valve port which define the inlet and the outlet are arranged to face each other.
A piston portion is connected to the end of the valve body, a cylinder portion is formed by valve casing on the outer periphery of the piston portion, and a substantially cylindrical bellows is attached to one surface of the piston portion. The piston, the piston, and the cylinder are provided with expansion medium reservoirs on both surfaces of the piston, and the expansion medium receiving pressure areas on both surfaces of the piston are different, and the pores communicating with the expansion medium reservoirs on both surfaces are formed in the piston. Wherein the bellows outer peripheral space is connected to an inlet of a valve casing.