JPH09303690A - Thermally actuated steam trap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent reverse flow surely while reducing the number of a parts by forming a leading-out passage opened/closed by a valve member on the lower wall member of a temperature control mechanism, and forming a seal surface for closing the leading-out passage on the valve member. SOLUTION: At the time of a normal condition in which the fluid pressure of an inlet 4 side is higher than that of an outlet 5 side, a check valve element 18 receives fluid pressure of the inlet 4 side, displaces downward, and mounts on the rib 16 of a valve member 17 so as to open a check valve opening 10. When the temperature in a valve chamber 3 is raised and an expansion medium 20 is expanded, a diaphragm 14 is displaced downward, the valve member 17 is seated on a lower wall member 19, the leading-out passage 8 of the lower wall member 19 is closed by the seal surface 30 of the valve member 17 so as to prevent leakage of steam. When the temperature in the valve chamber 3 is reduced and the expansion medium 20 is contracted, the diaphragm 14 is displaced upward, and the leading-out passage 8 is opened by the seal surface 30 so as to discharge condensation from an outlet 5. When fluid pressure of the outlet 5 becomes higher than that of the inlet 4 side, a check valve opening 10 is closed by the check valve element 18 so as to close a fluid passing hole 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steam trap for automatically discharging condensate generated in various steam-using devices and steam pipes, and more particularly, it is heated and cooled by steam and condensate and expands according to its temperature. The present invention relates to a heat-actuated steam trap that discharges condensed water below a desired temperature to the outside of a system by using a temperature control element containing a contracting medium.

[0002]

2. Description of the Related Art The basic structure of a heat-actuated steam trap is known, for example, from Japanese Patent Application Laid-Open No. 8-287787. As understood from the publication, a valve casing having an inlet, a valve chamber and an outlet, a valve seat member having a lead-out passage communicating the valve chamber and the outlet, and a diaphragm between two upper and lower wall members. The valve member is attached between the valve chamber and the outlet by attaching the valve member to the diaphragm by sealing the expansion medium between the upper wall member and the diaphragm by fixing the outer peripheral edge of the valve member. The valve seat member with the temperature control element facing the valve seat member, and a fluid passage gap is provided between the inner wall of the valve casing and the outer circumference of the temperature control element. The valve member has a seal surface for closing the lead-out path of the valve seat member when seated on the valve member.

When the temperature in the valve chamber rises, the expansion medium expands, and the valve member is seated on the valve seat member via the diaphragm to close the outlet passage. This prevents steam from leaking out. When the temperature in the valve chamber decreases, the expansion medium contracts, and the valve member separates from the valve seat member to open the outlet passage. This discharges the condensate out of the system.

[0004]

SUMMARY OF THE INVENTION In the above conventional one,
There has been a problem that the lead-out path opened and closed by the seat of the valve member has to be formed in a valve seat member different from the temperature control element, resulting in an increase in the number of parts. In addition, when the fluid pressure on the outlet side becomes higher than that on the inlet side, the fluid on the outlet side flows backward and reaches various steam-using devices, which lowers the thermal efficiency of the steam-using devices. In addition, there is a problem that steam-powered equipment may be damaged when an impact reverse flow occurs due to a water hammer at the outlet side.

Therefore, a technical object of the present invention is to provide a heat-actuated steam trap which can prevent backflow while forming a lead-out path in the temperature control element to reduce the number of parts.

[0006]

Means for Solving the Problems The technical means of the present invention taken to solve the above technical problems is to form an inlet, a valve chamber and an outlet in a valve casing, and to provide two upper and lower wall members. The outer peripheral edge of the diaphragm is fixed in between, the expansion medium is enclosed between the upper wall member and the diaphragm, and the temperature control element with the valve member attached to the diaphragm is installed in the valve chamber to control the inner peripheral wall of the valve casing and the temperature control. A seal member is provided to seal the outer periphery of the element, and a fluid passage hole is formed in the temperature control element by penetrating the upper wall member, the diaphragm and the valve member, and a check valve opening is provided in the fluid passage hole. Is provided with a check valve body that allows the flow from the inlet side to the outlet side and stops the flow in the opposite direction, forms a lead-out path in the lower wall member, and lower valve member when seated on the lower wall member of the valve member. A heat-actuated steam trap with a sealing surface formed on the valve member that closes the outlet path of the That.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION During normal operation, when the fluid pressure on the inlet side is higher than that on the outlet side, the check valve body opens the check valve port. When the expansion medium expands due to the rise in the temperature in the valve chamber, the valve member is seated on the lower wall member via the diaphragm, and the seal surface of the valve member closes the outlet passage of the lower wall member. This prevents vapor leakage. When the expansion medium contracts due to the decrease in the temperature in the valve chamber, the valve member separates from the lower wall member and opens the outlet passage. This discharges the condensate out of the system. Since the outlet passage is formed in the lower wall member of the temperature control element, the valve seat member for forming the outlet passage is unnecessary. This makes it possible to reduce the number of parts. When the fluid pressure on the outlet side becomes higher than that on the inlet side, the check valve body receives the action of the fluid pressure on the outlet side, closes the check valve opening, and shuts off the fluid passage hole. This prevents the backflow on the outlet side from reaching the various steam-using devices.

[0008]

EXAMPLE An example showing a concrete example of the above technical means will be described (see FIG. 1). In FIG. 1, the upper casing 1 and the lower casing 2 are screwed together to form a valve casing having a valve chamber 3 therein. The upper casing 1 has a valve chamber 3
An inlet 4 communicating with the lower casing 2 is formed in the lower casing 2.
Forming an outlet 5 communicating with

A temperature control element 9 is arranged in the valve chamber 3.
The temperature control element 9 includes an upper wall member 12 having a check valve port 10 and an injection port 11, a diaphragm 14 having a central opening 13, a central opening and a plurality of lateral openings laterally opened from the central opening. Valve member 17 in which a rib 16 is formed on the upper end of the opening 15 and the central opening, the check valve opening 10 and the rib 1.
6, a check valve body 18 is arranged so as to be movable up and down, a lower wall member 19 having a lead-out path 8 opened, and an expansion medium 20 enclosed between an upper wall member 12 and a diaphragm 14.

The valve member 17 is welded to the diaphragm 14 (reference numeral 21). Further, the diaphragm 1 is attached to the upper wall member 12.
Weld 4 (reference number 22). The check valve port 10, the central opening 13, and the opening 15 form a fluid passage hole 23 that penetrates the upper wall member 12, the diaphragm 14, and the valve member 17. The outer peripheral edges of the upper wall member 12, the diaphragm 14, and the lower wall member 19 are welded (reference numeral 24). Upper wall member 1
The expansion medium 20 is injected into the closed space between the diaphragm 2 and the diaphragm 14 from the injection port 11 and is closed with the plug member 25. The expansion medium 20 is formed of water, a liquid having a boiling point lower than that of water, or a mixture thereof.

The temperature control element 9 is mounted on a step portion 27 formed on the inner peripheral wall 26 of the lower casing 2 via a gasket 28 as a sealing means and held by a snap ring 29. Inner wall 2 of lower casing 2 by gasket 29
6 and the outer periphery of the temperature control element 9 are sealed. Valve member 1
A seal surface 30 for closing the lead-out path 8 of the lower wall member 19 when seated on the lower wall member 19 is formed on the lower surface of 7.

In a normal state in which the fluid pressure on the inlet 4 side is higher than that on the outlet 5 side, the check valve body 18 is displaced downward due to the action of the fluid pressure on the inlet 4 side and rests on the rib 16 of the valve member 17. The check valve port 10 is opened. When the temperature inside the valve chamber 3 rises, the expansion medium 20 expands. The expansion of the expansion medium 20 causes the diaphragm 14 to be displaced downward, so that the valve member 17 is seated on the lower wall member 19. When the valve member 17 is seated on the lower wall member 19, the seal surface 30 of the valve member 17 closes the outlet passage 8 of the lower wall member 19. This prevents vapor leakage. When the temperature inside the valve chamber 3 decreases, the expansion medium 20 contracts. The diaphragm 14 is displaced upward due to the contraction of the expansion medium 20, and the seal surface 30 of the valve member 17 is moved downward.
The lead-out path 8 is opened. As a result, the condensate is discharged from the outlet 5. When the fluid pressure on the outlet 5 side becomes higher than that on the inlet 4 side, the check valve body 18 receives the action of the fluid pressure on the outlet 5 side to close the check valve opening 10 and shut off the fluid passage hole 23.
This prevents backflow.

[0013]

The present invention has the following specific effects. As described above, the heat-actuated steam trap according to the present invention is
The number of parts can be reduced by forming the lead-out path opened and closed by the seat of the valve member in the lower wall member of the temperature control element. Moreover, since backflow can be prevented, the thermal efficiency of the steam-using device is not reduced or damaged.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of a heat-actuated steam trap according to the present invention.

[Explanation of symbols]

 1 Upper casing 2 Lower casing 3 Valve chamber 4 Inlet 5 Outlet 8 Outlet passage 9 Temperature control element 10 Check valve mouth 12 Upper wall member 14 Diaphragm 17 Valve member 18 Check valve body 19 Lower wall member 20 Expansion Medium 23 Fluid passage hole 26 Inner peripheral wall of lower casing 28 Gasket 30 Seal surface of valve member

Claims (1)

[Claims] 1. A diaphragm in which an inlet, a valve chamber and an outlet are formed in a valve casing, an outer peripheral edge of a diaphragm is fixed between two upper and lower wall members, and an expansion medium is enclosed between the upper wall member and the diaphragm. A temperature control element with a valve member attached to it is installed in the valve chamber, and a seal member is provided to seal between the inner peripheral wall of the valve casing and the outer periphery of the temperature control element, and the temperature control element has an upper wall. A check valve body is formed by penetrating the member, diaphragm and valve member to form a fluid passage hole, and providing a check valve port in the fluid passage hole to allow the flow from the inlet side to the outlet side and stop the flow in the opposite direction. The heat-responsive type is characterized in that the valve member is provided with a lead-out passage formed in the lower wall member, and a seal surface is formed in the valve member to close the lead-out passage of the lower wall member when seated on the lower wall member of the valve member. Steam trap.