JPS647370Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the structure of a detection section of a self-powered pressure regulating valve for liquid.

Self-powered pressure regulating valves have a diaphragm chamber separated by a partition wall and a detection hole provided in the partition wall to prevent performance deterioration due to the flow inside the valve box affecting the diaphragm, and a detection tube installed in this small hole. There are some devices that aim to greatly improve performance by inserting a diaphragm and having its tip protrude into the constricted part of the adjustment side fluid passage, thereby adding the effect of the fluid flow velocity to the diaphragm chamber pressure. However, when installed in vertical piping, depending on the flow direction of the liquid and the type of regulating valve (the position of the detection tube or detection hole is different), for example, if the detection tube or detection hole is downward, the water flow may not be possible. Air that has existed in the diaphragm chamber from before or air that has flowed into the diaphragm chamber during the operation of the regulating valve stagnates, making it impossible for the diaphragm chamber to be filled with liquid, resulting in hunting,
It may cause unstable operation of vibration, water hammer, etc. There is also a structure in which the flow inside the valve is actively guided into the diaphragm chamber without a partition wall in the diaphragm chamber, and the accumulated air is pushed out into the flow path along with the flow. In addition to poor flow performance, it is necessary to introduce a sufficient flow into the diaphragm chamber, which requires a wide open flow path, resulting in disadvantages such as a large regulating valve. Therefore, in self-powered pressure regulating valves that have a partition wall that separates the diaphragm chamber from the flow path, if the air in the diaphragm chamber cannot escape with vertical piping, an auxiliary device such as an automatic air bleed valve is generally used. In reality, the air is removed by manual means such as a manual air bleed valve, or the use is limited to horizontal piping due to unavoidable circumstances.

Figure 1 shows an example of this type of conventional self-operated pressure regulating valve (self-operated pressure reducing valve for liquids), in which 1 is a diaphragm, 2 is a diaphragm chamber, and 3
4 is a partition wall, 4 is a detection tube connecting the secondary flow path and the diaphragm chamber 2, 5 is an adjustment spring, 6 is a valve stem, 7 is a valve box having an inlet 7a and an outlet 7b, 8 is a valve stem guide part , 9 is a valve seat, 10 is a strainer, 11 is a valve body, 12 is a communication hole drilled in the valve body 11, 13 is a valve body spring weaker than the adjustment spring 5, and 14 is a spring protection cylinder, which is a valve body. When liquid flows into the primary flow path from the inlet 7a in the initial state (valve open state) where the body 11 is separated from the valve seat 9 by the force of the adjustment spring 5, the strainer 10 removes dust and the like. It flows out from the outlet 7b through the next flow path. In this case, the liquid flowing through the secondary flow path flows behind the valve body 11 through the communication hole 12, and this acts in the direction of closing the valve body 11, counteracting the pressure acting on the valve body 11 in the valve opening direction. do. Due to this effect, the secondary liquid pressure is not affected by fluctuations in the primary liquid pressure. Further, the liquid flowing through the secondary flow path flows into the diaphragm chamber 2 through the detection tube 4, which acts in a direction to compress the adjustment spring 5 through the diaphragm 1, and balances the force of the adjustment spring 5. In this way, when the secondary liquid pressure increases or decreases depending on the load (flow rate), the secondary liquid pressure acting on the diaphragm 1 and the adjustment spring 5 work together to adjust the opening degree of the valve body 11. As a result, the secondary liquid pressure applied to the diaphragm 1 always balances the force of the adjustment spring 5, so that the secondary liquid pressure is maintained at a constant value. Therefore, if this self-powered pressure regulating valve is used, for example, as a pressure reducing valve for individual water supply in mid-to-high-rise housing complexes that have rooftop tanks (elevated water tanks), water at the appropriate water pressure can be supplied to households on any floor. This means that it will be possible to supply By the way, in this type of self-powered pressure regulating valve, the diaphragm chamber 2 is filled with air before water is passed through, and the primary and secondary side piping are also filled with air, so when water is passed through, the flow path is is filled with water, and the inside of the diaphragm chamber 2 is also replaced with air, and some liquid flows in, but most of it remains air, and this air flows into the lower surface of the partition wall 3, that is, the diaphragm chamber 2 in FIG. It stays above. Thereafter, when the valve is activated, liquid flows into the diaphragm chamber 2 and liquid flows out from the diaphragm chamber 2, and the air inside the diaphragm chamber 2 flows between the detection tube 4, the valve stem 6, and the valve stem guide part 8. The liquid flows into the secondary flow path through the gap between them, and conversely, the liquid flows into the diaphragm chamber 2 from the secondary flow path through the detection tube 4 and the above-mentioned gap. Air is completely replaced by liquid. As described above, in this type of conventional regulating valve, the diaphragm chamber 2 is isolated by a partition wall, and the detection tube 4 is made to protrude into the constricted part of the secondary flow path, so that the suction effect of the pressure in the diaphragm chamber can be utilized. In normal use (horizontal piping), the spring protection tube 1 is placed below the valve box 7.
4 is positioned so that the detection tube 4
Due to the repeated expansion and contraction of the volume of the diaphragm chamber 2 due to the increase and decrease of the secondary side liquid pressure, combined with the Ventury effect of the secondary side opening of the diaphragm chamber 2.
By ensuring that the air inside is replaced with liquid, we have achieved a significant improvement in performance (flow characteristics). However, as mentioned above, when this valve is used as a pressure reducing valve for door-to-door water supply, it is installed just before the water meter, but recently, horizontal piping often cannot be stored in a pit with limited space, so As a result, there are many cases where vertical piping has to be used. Since the pit is located directly above the floor, the flow direction in the vertical piping is from top to bottom.
Due to such piping restrictions, self-powered pressure regulating valves are also installed in an orientation rotated 90 degrees to the right from the orientation shown in Figure 1. When the regulating valve is installed, as is clear from the explanation of the initial water flow, the air inside the pipes and valve during the initial water flow will eventually flow into the upper half of the diaphragm chamber 2 (the At the position shown in Figure 1, the part to the left of the valve stem 6) is filled with water, and it will never come out. Since the presence of such air would lead to extremely dangerous consequences, conventional self-operated pressure regulating valves of this type could not be used for such applications.

In view of these circumstances, the present invention has been developed to ensure that the air inside can be reliably and completely replaced with liquid during initial water flow even in the case of vertical piping in which the detection end is located below the diaphragm chamber. The purpose of the present invention is to provide a self-operated pressure regulating valve for liquids, which will be described below based on the illustrated embodiment, with the same parts and parts as in FIG. 1 being given the same reference numerals. In Figures 2 and 3, 15
16 is an annular groove formed on the lower surface of the partition wall 7 and communicated with the detection tube 4; 16 is an annular groove 1 that is airtightly attached to the annular groove 15 and is located on the side closer to the inlet 7a;
5 and the diaphragm chamber 2, and has at least one communication hole 16a.

Since the self-powered pressure regulating valve of this invention is configured as described above, it can be used in a position rotated 90 degrees to the right from the position shown in Figure 2, that is, when the flow direction is from top to bottom in a vertical pipe. However, during the first water flow, the air that filled the diaphragm chamber 2 flows through the communication hole 16a located at the top of the diaphragm chamber 2, the annular groove 15, and The liquid flows out through the detection tube 4 to the secondary flow path, and from the secondary flow path, the liquid flows into the diaphragm chamber 2 through the detection tube 4, the annular groove 15, and the communication hole 16a. The air in the diaphragm chamber 2 is completely replaced with liquid. To explain in more detail, when the water supply valve is opened and closed on the secondary side, the pressure in the secondary flow path decreases and increases, and the change in secondary liquid pressure is transmitted to the diaphragm chamber 2 through the detection tube 4, resulting in the posture shown in Fig. 2. In the vertical piping from top to bottom in the flow direction when the diaphragm 1 is rotated 90 degrees to the right, the force pushing the diaphragm 1 to the left decreases and increases, and the balance with the force pushing the adjustment spring 5 to the right is broken, and the diaphragm 1 The opening degree of the valve body 11 is adjusted by moving to the right or left, but at this time the volume of the diaphragm chamber 2 changes.
That is, when the water supply faucet is opened on the secondary side, the secondary side liquid pressure decreases and the diaphragm 1 moves to the right, so that the air staying above the diaphragm chamber 2 flows through the communication hole 16a installed above to the secondary side. discharged into the street. Further, when the water supply valve is closed on the secondary side, the secondary side liquid pressure increases and the diaphragm 1 moves to the left, so that the liquid in the secondary side flow path flows into the diaphragm chamber 2 from the detection tube 4. In this manner, the volume of the diaphragm chamber 2 is repeatedly contracted and expanded each time the water tap is opened and closed on the secondary side, and as a result, the air staying above the diaphragm chamber 2 is forcibly replaced with liquid. In addition, even when the flow rate is constant with the water tap open, that is, the opening degree of the valve body 11 is constant, the pressure at the secondary side opening of the detection tube 4 is lower than the pressure inside the diaphragm chamber 2 due to the Ventury effect. The residual air in 2 is detected by the detection tube 4.
The liquid is sucked out from the valve rod 6 and replaced with the liquid that has flowed in from the gap between the valve rod 6 and the valve rod guide portion 8. It goes without saying that when the present regulating valve is used in the illustrated position, the air in the diaphragm chamber 2 is completely replaced with liquid as described above. Therefore, unstable operations such as hunting, vibration, water hammer, etc. can be completely prevented.

In the case of the above embodiment, the annular groove 15 can be deformed into any other shape, and the point is that the groove may be configured so that the inside thereof communicates with the diaphragm chamber 2 only through the communication hole 16a. . Also, instead of drilling the communication hole 16a in the ring plate 16, a notch or cutout is provided on the side (left end) of the groove 15 closest to the inlet 7a, as shown by the dotted line in FIG.
Further, as shown in FIG.
Instead of forming a diaphragm chamber 2 side part of the detection tube 4, extend it to the inlet 7a side (left end) of the diaphragm chamber 2 and open its tip into the diaphragm chamber 2, or A thin tube connected to the small hole may be used and its tip may be positioned at the left end of the diaphragm chamber 2.
Although the case where the present regulating valve is used as a pressure reducing valve has been described above, it goes without saying that it can also be applied as various self-powered pressure regulating valves such as back pressure valves and differential pressure valves.

As mentioned above, the present invention has an extremely simple structure, and even in the case of vertical piping where the detection end is located below the diaphragm chamber, that is, on the floor side, the air inside the diaphragm chamber can be reliably and completely removed. Therefore, it is possible to provide a self-operated pressure regulating valve for liquids that operates stably without air obstruction. Furthermore, the present invention has the advantage that it can be provided without increasing the manufacturing cost because it only requires adding a few parts or performing simple processing to the conventional structure.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view showing an example of the structure of a conventional self-powered pressure regulating valve for liquids, and FIG. 2 is a longitudinal sectional view of an embodiment of the self-powered pressure regulating valve for liquids according to the present invention. 3 is a sectional view taken along the line -- in FIG. 2, and FIG. 4 is a perspective view of a detection tube used in another embodiment of the present invention. 1...Diaphragm, 2...Diaphragm chamber,
3... Bulkhead, 4... Detection tube, 6... Valve stem, 7...
Valve box, 7a...inlet, 7b...outlet, 11...
... Valve body, 15 ... Annular groove, 16 ... Ring plate, 1
6a...Communication hole.

Claims (1)

[Claims for Utility Model Registration] (1) A partition wall that separates the primary and secondary flow paths from the diaphragm chamber, and a small detection hole provided in the partition wall that communicates the adjustment side flow path and the diaphragm chamber. Or, in a self-operated pressure regulating valve for liquids in which the detection tube is located in the diaphragm chamber and located in the lower part, the detection small hole or the detection tube is configured to communicate only with the diaphragm chamber part on the upper side. Self-powered pressure regulating valve. (2) A small detection hole or a detection tube is formed in the partition wall and communicates with the diaphragm chamber only in the upper part through a groove that is kept airtight in the other part.
A self-operated pressure regulating valve for liquid according to claim (1) of the utility model registration, which is communicated with a diaphragm chamber. (3) The detection small hole or detection tube is communicated with the diaphragm chamber through a tube whose one end is connected to the detection hole or detection tube and the other end is opened into the upper diaphragm chamber portion. Self-operated pressure regulating valve for liquids as described in claim (1) for utility model registration.