JP2000055297A - Heat reaction type steam trap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To certainly close an effluent passage by arranging a temperature reaction member to energize a diaphragm or a valve member in the valve closing direction at the time of high temperature between the diaphragm or the valve member and a valve seat member or a casing. SOLUTION: An inlet 4, a valve chest 3 and an outlet 5 are formed of an upper casing 1 and a lower casing 2. A temperature control element 10 is arranged in the inside of the valve chest 3. The temperature control element 10 is formed by sealing an expansion medium 16 in an inside space 14 formed by fastening a wall member 12 and an outer peripheral edge of a diaphragm 15 and connecting a valve member 18 to the diaphragm 15. A shape memory alloy 21 one end of which is fixed on the valve member 18 and the other end of which is fixed on a valve seat member 8 is provided. The valve member 18 is energized in the valve closing direction at the time of high temperature by this shape memory alloy 21. An effluent passage 7 formed on an opening end on the side of the valve chest 3 of the outlet 5 is opened and closed by driving the valve member 18 in accordance with displacement of the diaphragm 15 by expansion and contraction of the expansion medium 16. As deforming force of the shape memory alloy 21 is applied as valve closing force at the time of high temperature, it is possible to certainly close the effluent passage 7.

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 equipment and steam pipes, and more particularly, to a temperature including a medium which is heated, expanded, cooled, and contracted. The present invention relates to a heat-responsive steam trap for discharging a fluid having a temperature lower than a desired temperature out of a system by using a control element.

[0002]

2. Description of the Related Art A thermally responsive steam trap using a temperature control element is disclosed, for example, in Japanese Patent Application Laid-Open No. 8-86397. As understood from the publication, an inlet, a valve chamber, and an outlet are formed by casing, an expansion medium is sealed in an internal space formed by fixing a wall member and an outer peripheral edge of the diaphragm, and a valve member is mounted on the diaphragm. A connected temperature control element is disposed in a valve chamber, and a valve member is driven by displacement of a diaphragm due to expansion and contraction of an expansion medium to open and close an outlet path formed at an opening end of a valve chamber at an outlet. .
The expansion medium is formed of water, a liquid having a lower boiling point than water, or a mixture thereof.

[0003]

When a high-temperature fluid having a temperature equal to or higher than a predetermined temperature flows into the valve chamber, the expansion medium expands and the pressure in the internal space increases, and the diaphragm opposes the fluid pressure on the inlet side. The valve member is displaced in the valve closing direction to close the lead-out path. This prevents the discharge of steam. When a low-temperature fluid of a predetermined temperature or less flows, the expansion medium contracts and the pressure in the internal space drops, and the diaphragm is displaced in the valve opening direction by the fluid pressure on the inlet side, and the valve member opens the outlet passage. . As a result, condensate and air are discharged outside the system.

[0004] However, in such a thermo-responsive steam trap of this type, when water, a liquid having a boiling point slightly lower than water, or a mixture thereof is used as the expansion medium, the outlet path cannot be completely closed, and the steam cannot be completely closed. There was a problem that caused leakage. This is because the pressure in the internal space that rises due to the expansion of the expansion medium is equal to or slightly higher than the fluid pressure on the inlet side, so that the valve closing force for closing the outlet path is weak. That's why.

[0005] Accordingly, it is an object of the present invention to provide a heat-responsive steam trap that can reliably close an outlet path.

[0006]

In order to solve the above technical problems, the technical means of the present invention is to form an inlet, a valve chamber, and an outlet by casing, and to form an outer peripheral edge of a wall member and a diaphragm. A temperature control element having a valve member connected to a diaphragm is arranged in a valve chamber, and the valve member is driven by displacement of the diaphragm due to expansion and contraction of the expansion medium, and an outlet is provided. A temperature responsive member for urging the diaphragm or the valve member in the valve closing direction when the temperature is high is disposed between the diaphragm or the valve member and the valve seat member or the casing. A heat-responsive steam trap is characterized in that:

[0007]

DETAILED DESCRIPTION OF THE INVENTION A thermally responsive steam trap according to the present invention has a temperature responsive member disposed between a diaphragm or a valve member and a valve seat member or a casing for urging the diaphragm or the valve member in a valve closing direction at a high temperature. are doing. Therefore, due to the pressure of the internal space that rises due to the expansion of the expansion medium and the deformation force of the temperature responsive member that urges the diaphragm or the valve member in the valve closing direction when the temperature is high, the valve member closes against the fluid pressure on the inlet side. Displace in the direction to close the lead-out path. As a result, the lead-out path can be reliably closed, and no steam leakage occurs.

[0008]

An embodiment showing a specific example of the above technical means will be described (see FIG. 1). Upper case 1 and lower case 2
Are screwed together to form a casing having a valve chamber 3 therein. An inlet 4 is formed in the upper case 1 and an outlet 5 is formed in the lower case 2. The inlet 4 and the outlet 5 are formed coaxially. A valve seat member 8 having an outlet 7 communicating the valve chamber 3 and the outlet 5 is screwed to the transverse wall 6 of the lower casing 2.

A temperature control element 10 is arranged above the valve seat member 8. The temperature control element 10 includes a wall member 12 having an inlet 11, a plug member 13 for sealing the inlet 11, and a diaphragm 15 forming an internal space 14 between the wall member 12.
And an expansion medium 16 sealed in the internal space 14, a valve member 18 fixed to the diaphragm 15 by welding (reference numeral 17), and an outer peripheral edge of the diaphragm 15 to the wall member 1.
2 and a lower wall member 20 fixed by welding (reference numeral 19). The expansion medium 16 includes water,
It is formed of a liquid having a lower boiling point than water, or a mixture thereof.

One end of a coil-shaped shape memory alloy 21 as a temperature responsive member is fixed to the valve member 18 and the other end is fixed to the valve seat member 8. One end of the shape memory alloy 21 may be fixed to the diaphragm 15. The other end is the lower casing 2
May be fixed. The shape memory alloy 21 contracts at a high temperature and urges the valve member 18 in the valve closing direction (toward the valve seat member 8). This shape memory alloy 21 allows the temperature control element 1
The outer periphery of the lower surface of the lower wall member 20 is held against the steps of a plurality of ribs 22 formed on the inner periphery of the lower casing 2. The shape memory alloy 21 extends at a low temperature and does not urge the valve member 18 in the valve closing direction. Reference numeral 23 denotes a screen fixed between the upper case 1 and the lower case 2 for capturing foreign matter.

The operation of this embodiment is as follows. At the time of starting, the temperature in the valve chamber 3 is low, the shape memory alloy 21 is expanded and does not urge the valve member 18 in the valve closing direction, and the expansion medium 16 is contracted. Therefore, the diaphragm 15
Is displaced in the valve opening direction by the fluid pressure on the inlet 4 side, and the valve member 18 is separated from the valve seat member 8 to open the outlet passage 7. Thereby, low-temperature condensate and air are discharged from the outlet 5.

When the temperature of the fluid flowing into the valve chamber 3 increases due to the discharge of the low-temperature fluid, the shape memory alloy 2
1 contracts and urges the valve member 18 in the valve closing direction. Then, when the temperature of the fluid flowing into the valve chamber 3 further increases, the expansion medium 16 expands. Due to the deformation force that urges the valve member 18 of the shape memory alloy 21 in the valve closing direction and the pressure in the internal space that rises due to the expansion of the expansion medium, the diaphragm 15 moves in the valve closing direction against the fluid pressure on the inlet 4 side. The valve member 18 is displaced, and the valve member 18 is seated on the valve seat member 8 to close the outlet passage 7. This prevents vapor leakage. As described above, since the deformation force of the shape memory alloy 21 is applied as the valve closing force, the lead-out path 7 can be reliably closed.

When the fluid temperature in the valve chamber 3 decreases due to heat radiation or the like, the expansion medium 16 contracts. Therefore, the diaphragm 15 is displaced in the valve opening direction by the fluid pressure on the inlet 4 side, and the valve member 18 separates from the valve seat member 8 to open the outlet passage 7. Thereby, low-temperature condensate and air are discharged from the outlet 5.

[0014]

The present invention has the following specific effects. As described above, according to the present invention, the outlet path is securely closed by disposing the temperature responsive member that urges the diaphragm or the valve member in the valve closing direction when the temperature is high between the diaphragm or the valve member and the valve seat member or the casing. As a result, steam leakage does not occur and energy is saved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a thermally responsive steam trap according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper casing 2 Lower casing 3 Valve room 4 Inlet 5 Outlet 7 Outgoing path 8 Valve seat member 10 Temperature control element 12 Wall member 14 Internal space 15 Diaphragm 16 Expansion medium 18 Valve member 21 Shape memory alloy

Claims (1)

[Claims] A temperature control wherein an inlet, a valve chamber, and an outlet are formed by casing, an expansion medium is sealed in an internal space formed by fixing a wall member and an outer peripheral edge of the diaphragm, and a valve member is connected to the diaphragm. A device in which a valve element is disposed in a valve chamber and a valve member is driven by displacement of a diaphragm due to expansion and contraction of an expansion medium to open and close an outlet path formed at an opening end of a valve chamber at an outlet. A thermally responsive steam trap, wherein a temperature responsive member for urging a diaphragm or a valve member in a valve closing direction at a high temperature is disposed between a member or a casing.