JPH0262760B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermostatic steam trap, and particularly to a thermostatic steam trap that provides a faithful response to condensate temperature.
The aim is to make it possible to easily guarantee long-term use.

Conventionally, when a heat-sensitive element such as a bimetal or thermowax is used for control for selectively eliminating condensate, it is often integrated with a valve by incorporating a coil spring to counter the biasing force of the element. The entire assembly, often referred to as a heat sensitive unit, is constantly exposed to hot fluid within the condensate chamber.

Because coil springs are forced to undergo stress relaxation due to heat, it is necessary to use higher quality materials or increase the size of the coils.

In order to eliminate such disadvantages, the present invention eliminates the opportunity for direct contact with high temperature fluid by arranging the coil spring on the secondary side, that is, in the outlet chamber.
This advantageously prevents material deterioration of the spring material due to thermal effects, making it possible to use inexpensive materials and reduce the size of the coil.

Furthermore, by eliminating the need for a space for housing the coil spring in the condensate reservoir, the present invention achieves placement of the heat-sensitive element close to the valve hole and miniaturization of the condensate reservoir to the minimum necessary size. Effectively suppresses unnecessary convection when the valve is closed,
The temperature distribution in the condensate storage chamber can be made more even, and the accuracy of the drainage temperature can be increased.

Regarding the above-mentioned problems with the conventional thermostatic steam trap, the present invention coaxially disposes a valve in the condensate reservoir communicating with the condensate inlet and a heat-sensitive unit that operates the valve according to the temperature in the reservoir. On the other hand, a push-up stem facing the lower end of the valve is disposed in an outlet chamber that communicates with the condensate outlet through a valve hole opened in a partition wall provided to the storage chamber and its compartment, and an push-up stem facing the lower end of the valve is arranged. This solution is achieved by applying a valve spring.

Practically speaking, it is preferable that the valve opening spring is a plug unit that has a coil spring and a spring seat built into the nipple, is closed, and is removably screwed facing the outlet chamber.

In other words, the valve opening spring in the outlet chamber comes into contact with the low-temperature fluid only when the valve is opened, and in the case of plug units in particular, there is virtually no contact even when the valve is opened, so there are no problems with the material due to thermal effects. Therefore, the initial characteristics can be maintained for a much longer period of time than in the case of a condensate reservoir arrangement of the valve opening spring.

FIG. 1 shows the valve closing behavior of an embodiment of the present invention, and FIG. 2 shows the main parts of the valve opening.

In the figure, 1 is an inlet, 2 is an outlet, 3 is a heat-sensitive element shown in the example of a bimetal column, 4 is a stem, 5 is a retaining ring, 6 is a valve, 7 is a valve seat, 8 is a push-up stem, and 9 10 is a coil spring, 10 is a spring seat, 11 is a nipple, 12 is a lid, 13 is an adjustment screw, 1
4 is an O-ring, 15 is a condensate reservoir communicating with the inlet 1, 16 is an outlet communicating with the condensate reservoir 15 through a valve hole 18 opened in a partition wall 17 serving to partition the condensate reservoir 15, and also communicating with the outlet 2. It is a room.

Note that 19 is a strainer and 20 is a cap.

Condensate coming from a pipe (not shown) connected to the inlet 1 flows into the condensate reservoir chamber 15, and when the temperature is low, the coil spring 9 is moved through the spring seat 10 when the heat-sensitive element 3 is inactive. By biasing the push-up stem 8, the valve 6
is opened as shown in Figure 2, and the low temperature condensate is released through the valve hole 18.
It is discharged from the outlet 2 through the outlet chamber 16.

As a result of the discharge of low-temperature condensate, the temperature of the condensate that continues to arrive in the condensate reservoir chamber 15 gradually increases, and when it reaches a predetermined temperature, the retaining ring 5
The stem 4 biases the valve 6 in the direction of closing the valve hole 18 against the biasing force of the coil spring 9 acting through the push-up stem 8, thereby causing the valve to close. The discharge of condensate stops.

Thereafter, at intervals determined by heat dissipation through the peripheral wall surrounding the condensate reservoir chamber 15, the heat-sensitive element 3 activates the operation of the coil spring 9 as a valve opening spring and presses the coil spring 9 every time the temperature in the condensate reservoir chamber decreases. There is nothing different from conventional steam traps of this type in that they cooperate via the raising stem 8 to selectively remove low-temperature condensate.

The coil spring 9 serving as the valve opening spring does not come into direct contact even with the low-temperature fluid that occurs when the temperature inside the condensate reservoir chamber 15 drops below a predetermined temperature, and is not affected by thermal effects from high-temperature condensate or steam. Since there is no risk of damage, the function can be maintained for a long time without causing deterioration or stress relaxation of the material based on it.

The push-up stem 8 has a receiving hole in its neck as shown in the figure, and is loosely engaged in the radial direction with the leg body collar of the valve 6 that fits into this receiving hole.
It is preferable not to be particular about the seating position with respect to the valve hole 18, and the lower half of the push-up stem 8 is
It is desirable that the expansion and contraction of the coil spring 9 be guided smoothly by a guide hole formed in the inner flange of the nipple 11.

The effects of this invention can be summarized as follows.

1. Inside the condensate reservoir chamber, only the minimum necessary parts consisting of a strainer, a heat-sensitive element, and a valve are required, making it easy and simple to downsize, and since the heat-sensitive element is closer to the valve hole, responsiveness is improved.

2. Since the valve closing spring is installed in the outlet chamber, it is not directly exposed to high temperature fluid, and there is no possibility of material deterioration such as stress relaxation.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of the present invention in the valve-closed position, and FIG. 2 is a cross-sectional view of the main parts in the same valve-open position. 1...Inlet, 2...Outlet, 3...Thermosensitive element, 6
... Valve, 8 ... Push-up stem, 9 ... Coil spring (valve opening spring), 15 ... Condensate reservoir chamber, 16 ... Outlet chamber.

Claims (1)

[Scope of Claims] 1. A valve and a heat-sensitive element that operates the valve according to the temperature in the reservoir are coaxially disposed in a condensate reservoir communicating with a condensate inlet, while a partition wall serving the reservoir and its division is provided. A thermostatic steamer is constructed by disposing a push-up stem facing the lower end of the valve in an outlet chamber that communicates with the condensate outlet through a valve hole opened in the valve, and a valve opening spring acting on the push-up stem. Trap 2: The valve opening spring is a plug unit that has a coil spring and a spring seat built into the nipple, is closed, and is removably screwed facing the outlet chamber, as set forth in claim 1. steam trap.