JP2001082693A - Float type drain trap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly discharge large quantity of low temperature drain and to use a float type drain trap without causing valve closing delay along an extensive pressure region from low pressure to high pressure. SOLUTION: A first valve hole 7 and a first valve seat 8 are formed on a lower part side wall of a valve chest 3, and a constantly opened orifice 16 is formed. A second valve seat 10 having a second valve hole 9 smaller in diameter than the first valve hole, to close the first valve hole at a position adhered to the first valve seat 8 and on which a contraction member 17 contracts a passing area of the orifice is arranged free to advance and retreat on the side of an outlet 6 of the first valve hole. An inlet chamber 12 communicated from the valve chest 3 to a back surface of the second valve seat 10 is formed, and a coil type shape memory alloy 13 is arranged as a temperature reacting member. The second valve seat opens and closes the first valve hole in a state of opening the first valve hole from the outlet side and a float 15 to open and close the second valve hole in a state where the second valve seat closes the first valve hole from the outlet side is arranged in the valve chest.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steam or compressed air and gas piping system by opening and closing a valve hole by driving a valve means with an open or closed float utilizing a specific gravity difference between a gas and a liquid. Regarding a float type drain trap that automatically discharges drain such as condensate and condensed water generated, in particular, a normally open orifice is provided separately from the valve hole to increase the drain discharge capacity and reduce the fluid pressure of the piping system. It relates to a device that can be used over a wide pressure range from low pressure to high pressure.

[0002]

2. Description of the Related Art A float type drain trap provided with a normally open orifice separately from a valve hole is disclosed, for example, in Japanese Patent Laid-Open No. 10-14 / 1998.
No. 1593. As understood from the publication, a valve chamber is formed in a casing having an inlet and an outlet, a valve seat having a valve hole communicating with the valve chamber and the outlet is provided at a lower portion of the valve chamber, and a float disposed in the valve chamber. The valve member is driven to open and close the valve hole, and a normally open orifice communicating the valve chamber and the outlet is provided at a lower portion of the valve chamber.

[0003] A float type drain trap usable over a wide pressure range from low pressure to high pressure is, for example,
It is disclosed in Japanese Patent Publication No. 3-35560. As understood from the publication, a valve chamber is formed in a casing having an inlet and an outlet, a valve seat having a valve hole communicating with the valve chamber and the outlet is provided at a lower portion of the valve chamber, and a float disposed in the valve chamber. The valve member is driven to open and close the valve hole, the first valve seat having the first valve hole and fixedly provided in the valve chamber, and the second valve hole having a smaller diameter than the first valve hole. A second valve seat is formed to extend and retract through the first valve hole and is configured to open and close the first valve hole from the valve chamber side. The first valve hole is opened and closed by the second valve seat against the valve opening action spring by its own weight and the fluid pressure on the inlet side.

[0004]

The above-mentioned conventional Japanese Patent Application Laid-Open No.
The float type drain trap disclosed in JP-A-141593 is excellent because the drain discharge capacity can be increased. However, since the passage area of the orifice is constant, the float type drain trap has a low When a large amount of drain is generated, it takes a long time to discharge the drain.

[0005] Further, the above-mentioned conventional Japanese Patent Publication No. 3-35560.
The float type drain trap disclosed in Japanese Patent Application Laid-Open Publication No. H10-150,086 has a problem in that when used in a low-pressure steam piping system, there is a risk of causing steam leakage. That is, when the float descends due to the discharge of the condensate, the second valve hole is first closed by the float, and then the first valve hole is closed by the second valve seat whose second valve hole is closed by the float. Therefore, there is a risk of causing a delay in closing the first valve hole.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a float type drain trap which can quickly discharge a large amount of low-temperature drain and can be used over a wide pressure range from low pressure to high pressure without causing valve closing delay. It is.

[0007]

The technical means of the present invention taken to solve the above technical problem is to form a valve chamber in a casing having an inlet and an outlet, and to form the valve chamber and the outlet. A valve seat with a communicating valve hole is provided in the lower part of the valve chamber, and a valve member is driven by a float arranged in the valve chamber to open and close the valve hole, and an orifice communicating the valve chamber and the outlet is provided in the lower part of the valve chamber. And a first valve fixedly provided in the valve chamber having a first valve hole.
A valve seat having a second valve hole having a diameter smaller than that of the first valve hole, disposed at an outlet side of the orifice and the first valve hole, opening and closing the first valve hole from the outlet side, and changing a passage area of the orifice; 2
A valve seat is formed from the valve seat, and the first valve hole is opened and the orifice passage area is increased at low temperatures in response to the fluid temperature at the inlet side, and the first valve hole is closed and the orifice passage area is reduced at high temperatures. As described above, the temperature responsive member is connected to the second valve seat, and the float opens and closes the first valve hole in a state where the second valve seat opens the first valve hole and the passage area of the orifice is increased.
The float type drain trap is characterized in that the float opens and closes the second valve hole with the second valve seat closing the first valve hole and reducing the passage area of the orifice.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A float type drain trap according to the present invention uses a temperature responsive member which responds to the fluid temperature on the inlet side when the fluid temperature on the inlet side is low, that is, when the fluid pressure on the inlet side is low, The two valve seats open the first valve hole of the first valve seat from the outlet 6 side and increase the passage area of the orifice. Then, the float opens and closes the first valve hole due to its rising and falling. When the fluid temperature on the inlet side is high, that is, when the fluid pressure on the inlet side is high, the second valve seat is connected to the outlet 6.
The first valve hole of the first valve seat is closed from the outlet side from the side and the passage area of the orifice is reduced. Then, the float opens and closes the second valve hole having a smaller diameter than the first valve hole due to its rising and falling. In this way, at low temperature, ie, low pressure, the second valve seat opens the first valve hole from the outlet 6 side, and the float opens and closes the first valve hole with a large orifice passage area. The seat closes the first valve hole from the outlet 6 side and the float opens and closes the second valve hole with a smaller diameter than the first valve hole with the orifice passage area narrowed. It can be discharged and can be used over a wide pressure range from low pressure to high pressure without causing valve closing delay.

[0009]

FIG. 1 is a sectional view showing an embodiment of a float type drain trap according to the present invention. This embodiment is applied to a free float steam trap. The casing of the free-float type steam trap is composed of the main body 1 and the main body 1
And a valve body 3 inside.
The main body 1 has an inlet 4, an outlet passage 5, and an outlet 6, and the inlet 4 communicates with an upper part of the valve chamber 3.

A first valve seat 8 having a first valve hole 7 is formed in a lower side wall of the valve chamber 3 and a normally open orifice 16 is formed. The lower part of the valve chamber 3 communicates with the outlet 6 via the outlet passage 5 from the first valve hole 7 and the orifice 16. A second valve hole 9 having a smaller diameter than the first valve hole 7 and a throttle member 17 provided on the first valve hole 7 and the outlet 6 side of the orifice 16.
The valve seat 10 is disposed so as to be able to advance and retreat. The second valve seat 10 is the valve chamber 3
The first valve hole 7 is closed at a position displaced to the side and in close contact with the first valve seat 8, and the throttle member 17 narrows the passage area of the orifice 16. The lower portion of the valve chamber 3 communicates with the outlet 6 via the outlet passage 5 from the second valve hole 7 and the narrowed orifice 16.

The communication passage 1 is provided on the back of the second valve seat 10 from the valve chamber 3.
An inlet chamber 12 for introducing a fluid on the inlet 4 side through 1 is formed, and a coil-shaped shape memory alloy 13 as a temperature responsive member is disposed in the inlet chamber 12. The shape memory alloy 13 has both sides connected to the second valve seat 10 and the plug 14, respectively, and contracts at low temperature to open the second valve seat 10 from the first valve hole 7 and increase the passage area of the orifice 16. Then, it extends at high temperature to close the second valve seat 10 in the first valve hole 7 and to narrow the passage area of the orifice 16. As the temperature responsive member, besides the shape memory alloy, a bimetal, a thermowax, a liquid bellows, or the like can be used. A hollow spherical float 15 is arranged in the valve chamber 3 in a free state. Float 1
5, the second valve seat 10 opens and closes the first valve hole 7 in a state where the first valve hole 7 is opened and the passage area of the orifice 16 is increased, and the second valve seat 10 closes the first valve hole 7 and The second valve hole 9 is opened and closed with the passage area of the orifice 16 narrowed.

The operation of the free-float type steam trap of the above embodiment is as follows. When the fluid temperature on the inlet 4 side is low, that is, when the fluid pressure on the inlet 4 side is low, the shape memory alloy 13 contracts and displaces the second valve seat 10 toward the plug 14, and the second valve seat 10 moves The first valve hole 7 of the first valve seat 8 is opened from the side 6 and the passage area of the orifice 16 is increased. Then, the first valve hole 7 is opened and closed by the floating and descending of the float 15 to automatically drain the drain 6.
To be discharged. If the fluid temperature on the inlet 4 side is high,
When the fluid pressure on the side is high, the shape memory alloy 13 expands and displaces the second valve seat 10 toward the valve chamber 3, and the second valve seat 10 moves from the outlet 6 side to the first valve seat 8. 1 The valve hole 7 is closed and the passage area of the orifice 16 is reduced. And
The second valve hole 9 having a smaller diameter than the first valve hole 7 is opened and closed by the floating and falling of the float 15, and the drain is automatically discharged to the outlet 6.

In the above embodiment, the present invention is applied to a free-float type steam trap, but can also be applied to a lever-float type steam trap. Further, the present invention can be applied not only to a float type steam trap but also to a float type air trap and a float type gas trap.

[0014]

As described above, according to the present invention, when the temperature is low, that is, when the pressure is low, the first valve hole is opened from the outlet side of the second valve seat and the float is moved to the first position with the orifice passage area increased.
The valve hole is opened and closed. At high temperature, that is, high pressure, the second valve seat closes the first valve hole from the outlet side and the float opens and closes the second valve hole smaller in diameter than the first valve hole with the orifice passage area narrowed. Therefore, a large amount of low-temperature drain can be quickly discharged, and an excellent effect that it can be used over a wide pressure range from a low pressure to a high pressure without causing a valve closing delay is produced.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment in which a float type drain trap of the present invention is applied to a free float type steam trap.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 2 Lid 3 Valve room 4 Inlet 6 Outlet 7 1st valve hole 8 1st valve seat 9 2nd valve hole 10 2nd valve seat 13 Spring 15 Float 16 Orifice 17 Throttle member

Claims (1)

[Claims] A valve chamber is formed in a casing having an inlet and an outlet, a valve seat having a valve hole communicating with the valve chamber and the outlet is provided at a lower portion of the valve chamber, and the valve member is floated in the valve chamber. A first valve seat having a first valve hole fixedly provided in the valve chamber, the first valve seat having an orifice communicating with the valve chamber and the outlet provided in a lower portion of the valve chamber; A second valve seat having a second valve hole smaller in diameter than the hole, the second valve seat being disposed on the outlet side of the orifice and the first valve hole, opening and closing the first valve hole from the outlet side, and changing the passage area of the orifice; In response to the fluid temperature on the inlet side, the first valve hole is opened at a low temperature and the orifice passage area is increased, and the first valve hole is closed at a high temperature and the orifice passage area is reduced at a high temperature. The second valve seat opens the first valve hole and passes through the orifice. The float opens and closes the first valve hole with the area increased, the second valve seat closes the first valve hole, and the float opens and closes the second valve hole with the orifice passage area reduced. Floating drain trap.