JPH0663598B2 - Temperature control valve - Google Patents

Description

The present invention relates to a thermoresponsive element having no self-recovery ability, such as a thermowax or a bimetal plate, which is formed by stacking a plurality of thermowaxes or bimetal plates. The present invention relates to a temperature control valve for automatically discharging a fluid having a temperature equal to or lower than a predetermined temperature from a steam system, and more particularly to a means for maintaining a constant discharge temperature even when the pressure of the steam system fluctuates.

INDUSTRIAL APPLICABILITY The present invention is used in the field of flow rate control according to the temperature of a fluid, particularly in the field of control for automatically discharging a fluid having a temperature below a predetermined temperature from a vapor system to the outside of the system.

2. Description of the Related Art Thermo-responsive elements that are stacked with thermowax and bimetal plates do not have a self-recovery ability, so a return spring is required. One basic structure of a temperature control valve using such a heat responsive element is that the heat responsive element, an intermediate member, and a return spring are sequentially stacked, and both ends are arranged so as to be in contact with the immovable wall of the valve casing. It is a combination of valve bodies.

An example of this is shown in Japanese Utility Model Publication No. 53-13948. That is, the valve seat member having the valve port is fixed to the bottom wall of the valve chamber, and the adjusting rod having the connecting rod fitting hole is screwed to the ceiling wall of the valve chamber. Here, the valve port and the connecting rod fitting hole are arranged on the same axis. An upper end of the connecting rod is displaceably fitted in the connecting rod fitting hole, and a lower end thereof is fitted in a hole formed in the intermediate member. A heat responsive element is arranged around the connecting rod. The heat responsive element is formed by stacking a plurality of bimetal plates, the upper end surface of which is in contact with the inner end of the adjusting rod that is the immovable wall of the valve casing, and the lower end surface is in contact with the upper end surface of the intermediate member. A return spring is interposed between the intermediate member and the bottom wall of the valve chamber. A valve element is connected to the intermediate member.

When the temperature of the surrounding fluid rises, the thermoresponsive element expands while compressing the return spring via the intermediate member. In response to this, the valve element coupled to the intermediate member is displaced, hitting the valve seat and closing the valve port. When the temperature of the surrounding fluid decreases, the extension force of the thermoresponsive element is weakened, so that the thermoresponsive element is pushed back by the return spring through the intermediate member. In response to this, the valve element separates from the valve seat and opens the valve opening.

Problems to be Solved by the Invention In this case, there is a problem that the discharge temperature changes when the pressure of the steam system changes. That is, when the pressure of the fluid flowing into the valve chamber becomes high, the pressure difference before and after the valve opening becomes large and the discharge temperature decreases, and when the pressure becomes low, the discharge temperature increases. In particular, when the discharge temperature is set to a temperature 3 to 4 degrees lower than the saturation temperature to be used as a steam trap, the condensate is retained or steam is blown off, so that the function cannot be achieved.

Means for Solving Problems The technical means of the present invention taken to solve the above problems is to form an inlet, a valve chamber, and an outlet in a valve casing, and to form a valve port communicating the valve chamber and the outlet. The formed valve seat member is fixed to the bottom wall of the valve chamber, the adjustment rod is screwed to the ceiling wall of the valve chamber, and the connecting rod with the valve body for opening and closing the valve opening at the lower end is formed integrally or separately. It is located in the valve chamber and has a connecting rod fitting hole that fits the upper end of the connecting rod in a displaceable manner, and the valve chamber is airtightly separated into a lower chamber communicating with the inlet and an upper chamber communicating with the outside air. A response member is provided, and a thermal response element, an intermediate member, and a return spring are sequentially stacked around the connection rod between the pressure reception response member and the bottom wall of the valve chamber, and pressure is applied between the adjustment rod and the pressure reception response member. A balance spring is arranged.

Action The action of the above technical means is as follows.

The thermoresponsive element expands while compressing the return spring according to the temperature of the surrounding fluid. Along with that, the intermediate member and the connecting rod formed integrally with or separately from the valve body are displaced in the valve opening direction, and the valve body hits the valve seat to close the valve opening. The pressure receiving responsive member is displaced to a position balanced with the urging force of the pressure balance spring according to the pressure of the fluid flowing into the valve chamber. That is, when the pressure is high, the pressure balance spring is compressed and displaced upward, and when the pressure is low, the pressure balance spring is displaced downward. Therefore, the higher the pressure, the larger the amount of refraction to the valve closing of the heat responsive element, and the lower the pressure, the smaller the lift amount. By designing the elastic force of the pressure balance spring within the range where the fluid pressure and the saturation temperature are close to a straight line,
Even if the pressure fluctuates, the discharge temperature can be kept almost constant.

EFFECTS OF THE INVENTION The present invention produces the following unique effects.

The thermoresponsive element can further expand by compressing the pressure balance spring even after the valve is closed, preventing an abnormal increase in internal stress of the thermoresponsive element, preventing performance deterioration, and extending the life.

Example An example showing a specific example of the above technical means will be described (see FIG. 1).

A cylinder member 2 is screwed to the main body 1 and a lid 3 is screwed to the cylinder member 2 to form a valve casing having a valve chamber 4 inside. Gaskets 5 and 6 are interposed between the main body 1 and the cylinder member 2 and between the cylinder member 2 and the lid 3 to maintain airtightness. An inlet 7 communicates with the valve chamber 4 through a through hole 8 and an outlet 9 communicates with the through hole 10 through a valve port 11 and a through hole 12. Through hole 1
0 and the valve port 11 are formed in the valve seat member 13 screwed to the main body 1. A gasket 14 is provided between the main body 1 and the valve seat member 13.
Keeps airtightness.

A screen 15 is arranged in the valve chamber 4 to regulate the flow direction of the fluid flowing from the inlet 7 and to capture foreign matter in the fluid. The connecting rod 16 is arranged so as to face the valve opening 11. A valve body 17 is integrally formed at the lower end of the connecting rod 16. An adjustment rod 18 is screwed to the lid 3 so that the adjustment rod 18 can be moved back and forth. The adjusting rod 18 is made to project from the lid 3 at the upper part thereof, and a cutout 19 into which the tip of a tool such as a screwdriver is fitted is provided on the upper end surface thereof. Adjusting rod 18
A lock nut 20 is attached to the projecting portion of the to prevent loosening and is covered with a cap 21.

A piston 24, which slides on the inner peripheral surface of the cylinder member 2 and has piston rings 22 and 23 on the outer periphery, is arranged in the valve chamber 4. As a result, the valve chamber 4 is divided into the lower chamber 4a and the upper chamber 4
b. Airtightly separated. The lower chamber 4a communicates with the inlet 7, and the upper chamber 4b communicates with the outside air through the opening 33 formed in the cylinder member 2. The lower end surface of the adjusting rod 18 and the piston 2
A pressure balance spring 25 is arranged between the four. Piston 2
4, a connecting rod fitting hole 26 is formed on the same axis as the valve opening 1,
The upper end of the connecting rod 16 is displaceably fitted.

A snap ring 27 is attached to the center of the connecting rod 16. A bimetal laminated body 28 is arranged around the connecting rod 16 between the lower end surface of the piston 24 and the upper end surface of the snap ring 27. The bimetal laminated body 28 is composed of two bimetal discs 29, which are combined in different bending directions, to form a pair, and a plurality of pairs are stacked. A spacer 30 is interposed between each bimetal pair. The intermediate member 31 is arranged on the lower end surface of the snap ring 27. The return spring 32 is arranged between the lower end surface of the intermediate member 31 and the bottom wall of the valve chamber 3.

The fluid enters the valve chamber 4 from the inlet 7 through the through hole 8 and the screen 15, flows around the pi-metal laminated body 28, and flows out from the through hole 10 and the valve opening 11 through the through hole 12 to the outlet 9. The piston 24 is displaced to a position where the fluid flowing into the valve chamber 4, the pressure, and the elastic force of the pressure balance spring 25 are balanced. When the temperature of the surrounding fluid rises and the bimetal laminated body 28 is heated to a high temperature, each bimetal disc 29 is heated.
Bends and its degree increases, so that the return spring 32 is compressed via the intermediate member 31 and extends in the stacking direction. Along with this, the intermediate member 31 and the connecting rod 16 are connected to the valve opening 11
Direction, the opening of the valve opening 11 gradually decreases, and the valve body 17 closes the valve opening 11 at the end. This valve closed state is shown in FIG.

Even after the valve is closed, the temperature of the valve chamber 1 further rises if a higher temperature fluid flows in, for example, because the fluid leaks. Then, the bimetal laminated body 28 further expands while compressing the pressure balance spring 25.

If the temperature of the fluid in the valve chamber 4 drops, the bimetal laminate 2
Since the bending force of No. 8 is small, it is pushed back by the return spring 32 via the intermediate member 31. Along with this, the intermediate member 3
1 and the connecting rod 16 are displaced in the direction away from the valve port 11,
The valve port 11 is opened, and the fluid in the valve chamber 4 flows out to the outlet 9 again.

When the pressure of the fluid flowing into the valve chamber 4 increases, the piston 24 is displaced further upward, increasing the lift amount of the bimetal laminate 28 until the valve is closed, and decreasing the pressure decreases the lift amount. Since the pressure balance spring is designed so that the amount of deformation of the fluid due to the pressure changes linearly with the saturation temperature, even if the pressure fluctuates, the fluid below the set temperature can be automatically discharged.

The set temperature can be adjusted by moving the adjusting rod 18 forward and backward. That is, if the adjusting rod 18 is screwed in, the set temperature (the temperature of the fluid to be discharged) is lowered, and if it is screwed up, the set temperature is raised.

Although the piston is used as the pressure receiving member in the above embodiment, a bellows or the like may be used.

[Brief description of drawings]

 FIG. 1 is a sectional view of an embodiment of the temperature control valve of the present invention. 1: Main body, 2: Cylinder member 3: Lid, 4: Valve chamber 7: Inlet, 9: Outlet 11: Valve opening, 13: Valve seat member 16: Connecting rod, 17: Valve body 18: Adjusting rod, 24: Piston 25: Pressure balance spring, 26: Connecting rod fitting hole 28: Bimetal laminated body, 31: Intermediate member 32: Return spring

Claims (1)

[Claims] 1. A valve seat member having an inlet, a valve chamber and an outlet formed by a valve casing and having a valve port communicating the valve chamber and the outlet is fixed to a bottom wall of the valve chamber and adjusted to a ceiling wall of the valve chamber. A connecting rod with a rod that is screwed together and has a valve body that opens and closes the valve opening at the lower end is formed integrally or separately and is placed in the valve chamber, and the upper end of the connecting rod is displaceably fitted. A pressure-responsive member that has a hole and is airtightly separated between a lower chamber communicating the valve chamber with the inlet and an upper chamber communicating with the outside air is provided between the pressure-responsive member and the bottom wall of the valve chamber around the connecting rod. A temperature control valve in which a heat responsive element, an intermediate member, and a return spring are sequentially stacked on top of each other, and a pressure balance spring is disposed between the adjusting rod and the pressure receiving responsive member.