JPH0193687A - Lift valve device - Google Patents

Abstract

PURPOSE:To obtain a complete sealing performance by loading a soft, elastic seal member suitably thicker at its side to be subjected to high pressure between a valve box and a piston. CONSTITUTION:A seal member 11 is tightened and fixed between a flange 13 of a valve box 1 and a flange 14 attached to a valve cover 2. When water is fed, the water flows from an inlet passage (a) into a valve casing or a piston chamber (b), and then flows through the valve opening into an outlet passage (c). Because the seal member 11 is sufficiently soft and elastic, and an internal force homogeneously acts in the seal material, slacks of the seal member 11 are pressed by the pressure in the piston chamber (b) to form adequate configuration. Thus, the piston side space is completely separated from the piston chamber (b) by the seal member 11.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application This invention relates to a lift valve device equipped with a balancing piston.

(B) Conventional technology Conventionally, in lift valve devices equipped with a reciprocating piston for balancing the valve thrust, in order to prevent leakage from the piston gap, a ring-shaped backing is interposed in the piston gap. , and if complete sealing is required,
Diaphragm and bellows devices were used.

(c) Problems to be solved by the invention A reciprocating piston is suitable for high pressure differences, and if the pressure acting on the piston is constant, the operating force during its displacement does not change. Functionally, it is said to be very convenient as a balance piston.

However, since the piston and the cylinder form a relatively displaceable gap surface, leakage from this gap is sometimes a critical problem for the valve device. This is because even if a sufficient backing is installed there, sealing deterioration due to wear cannot be avoided.

Therefore, even if a diaphragm is unavoidably used in the balance piston of a lift valve device (the same applies to bellows), there is no problem as far as leakage is concerned.

However, unlike a reciprocating piston, a diaphragm device has a flexible plate fixed at its outer periphery, and the pressure difference acting between both sides causes the annular diaphragm portion at the outer periphery of the diaphragm pressure receiving plate to deform and actuate. ,
It was structurally unsuitable for applying a large pressure difference, and had the disadvantage that the displacement distance of the diaphragm spindle could not be made very large.

Moreover, the operating force generated on the diaphragm has complex functional properties such as the magnitude of the pressure difference applied, the diaphragm area, thickness, appropriate elasticity, and tensile strength, and is not simple in practice.

This invention solves the above-mentioned problems of the conventional lift valve, and provides a lift valve that has a small and simple structure and uses a reciprocating piston as the valve thrust balancing piston, which is completely free of leakage concerns. The purpose is to provide equipment.

(d) Means for solving the problem As mentioned earlier, the diaphragm is made up of pressure that acts on the diaphragm pressure plate fixed in the center and the annular diaphragm part outside the pressure plate. Since this annular portion is deformed to perform piston action, it is made of an elastic member that has sufficient strength mainly in the radial direction in a plane and has a relatively thin thickness.

This means that the elastic member is only two-dimensional, that is, mainly
It seems that the mechanism is made cramped by being used as a member that deforms and displaces only in the direction along the surface.

Now, if we enlarge the diaphragm pressure plate to the size of the diaphragm plate, it is clearly the structure of a reciprocating piston itself, and the diaphragm part that surrounds its outer circumference in a linear shape is a volumetric type. It can be considered that the main function as a machine has been lost, and for the time being it has become a member that only has the function of sealing the gap.

In the present invention, such a structure is separately assumed, and the seal portion considered in this way is made of an elastic member that can be displaced and deformed three-dimensionally (at least a surface that does not easily protrude from the gap). By configuring the structure to be strong (it only needs to be strong), we were able to realize a mechanism that achieves that purpose.

This invention will be explained based on the drawings showing an embodiment thereof. Fig. 1 shows a vertical cross-sectional view of a lift valve device which is an embodiment of the invention in a valve fully open state, and Fig. 2 shows the same lift valve device as an embodiment of the invention. It is a longitudinal cross-sectional view showing the valve closed state of the valve device. 1 indicates the valve box, and 2 indicates the valve lid. a and C are inlet channels, respectively;
Use as an exit flow path. 3 is a valve seat, 4 is a valve body part that opens and closes perpendicular to the valve seat surface, that is, a lift valve, and a screw hole of a screw bush 7 provided in the valve cover 2 is connected to a screw 6 of an integrated spindle 5. penetrates and is retained.

Reference numeral 16 denotes a handle fixed to a threaded bushing, and when the handle is turned, the threaded bushing 7 rotates, and the valve body portion 4 can be opened and closed via the spindle 5. 8 is a piston cylinder perpendicular to the valve closing surface, and its cross-sectional area perpendicular to the axis is equal to the operating area of the valve body 4. It is fitted through a gap IO.

When the valve body 4 is in the fully open position (as shown in FIG. 1), the piston cylinder 8 moves from the edge of the cylinder hole 9 into the piston chamber by at least the maximum lift of the lift valve. It is necessary to assume a state of prominence. Reference numeral 11 denotes a sealing member made of a rubber-like elastic material and formed to cover the piston end 12 protruding into the piston chamber, the end edge of the cylinder hole 9, and the gap 10. Reference numeral 13 designates a flange formed on the upper part of the valve box 1 to connect the 7 flange 14 provided on the valve cover 2. And these flanges 13.14
In between, the seal member 11 is tightened by sandwiching the seal member flange portion 15 that juts out laterally from the vicinity of the portion where the seal member 11 contacts the flange 13 of the valve body l. The sealing member 11 is made of a soft rubber-like elastic material with an appropriate thickness.
To be more specific, if you apply a slight negative pressure to the inside of a rubber ball made from the same material, if it is thin, it will collapse immediately, and if it is thick, it will collapse. It can be seen that a thin ball will collapse immediately as pressure is applied, and a thick ball will gradually become smaller as the internal air is compressed. ), but also in the three-dimensional direction, that is, in the thickness direction, this can be seen as a result of homogenizing the force.

(E) Function The valve of the lift valve device configured as above is fully opened (the first
In the state shown in the figure), when water is passed (water also refers to other fluids), water enters the valve box chamber, ie, the piston chamber, from the inlet flow path a, and exits to the outlet flow path C through the valve opening. At this time, the sealing member 11 is sufficiently elastically soft and the force inside the material can act homogeneously, so the pressure inside the piston chamber acting as indicated by the small arrow is able to shape the slack portion of the member 11 into an appropriate curved shape. Formed under pressure (increasing thickness in some places). (Thus, the sealing member 11 completely isolates the piston side space from the piston chamber, completely preventing leakage from the chamber, and the force acting on the piston cylinder body 8 is effectively converted into valve thrust. It is something that can be balanced.

Therefore, the valve can be easily opened and closed by simply turning the handle 16. Incidentally, FIG. It is like a hollow O-ring with a cutout in the middle and can withstand a large pressure difference.The properties, structure, mode of operation, and effects of the sealing member 11 have been explained in detail above, but I would like to add an additional comment: It is a backing member for gaps, and its strength is different from that required for diaphragms and the like.

Basically, this means that the strength of the portion corresponding to the leakage gap may be sufficient to withstand extrusion. In other words, even if the internal pressure from the piston chamber in the drawing can withstand tens of atmospheres, if pressure is applied from the opposite side, that is, from the outside,
It is possible that it could easily inflate like a balloon. If you look at it, this is a remarkable effect and a feature.ExamplesAs explained above, by implementing the present invention in a lift valve device, a remarkable effect can be obtained, and the present invention In keeping with the gist, various structural changes can be made to meet universal implementation requirements. (A) Until now, leakage problems have forced the field of automatic control valves to rely on compromised diaphragm devices, but the present invention reduces the need for this. For example, in FIG. 1, if the screw bushing 7 is removed and a coil spring is interposed between the upper surface side of the piston part 12 and the lower surface side of the valve cover 2, this lift valve device can transfer the secondary pressure to the spring. A constant pressure lift valve device that regulates by the strength of is completed.

(B) As for the properties of the sealing member 11, unlike a diaphragm, it does not require much strength, which is also a remarkable feature of the present invention. Although there are polymers with excellent heat, oil, and chemical resistance, until now they have not been able to be used in diaphragms in terms of strength.

However, in the present invention, it becomes possible to implement and contribute to various lift valve devices as an excellent balance piston by utilizing these.

(C) The sealing member 11 has various embodiments in terms of its structure, that is, it may be formed to match the shape of the piston, or its elasticity may be partially modified to adjust its tendency to deform under pressure.

Also suitable is a structure in which a sponge-like member is bonded to a relatively thin member.

(g) Effects of the Invention As explained above, this invention provides a valve thrust valve with a piston for anti-slip balance, and a foot valve device in which the thickness is set appropriately from the high pressure side with respect to the leakage gap of the piston. It has a simple structure in which a soft elastic sealing member is installed between the valve box and the piston, which ensures the normal operation of the balance piston and achieves the same complete sealing effect as the diaphragm device. Needless to say, the balance valve device according to the present invention not only improves the operability and durability of the lift valve device, but also has extremely remarkable effects as a main part of automatic valve devices such as constant pressure valves and constant flow valves.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 both show longitudinal sectional views of a lift/valve device that is an embodiment of the present invention. 1. Valve box, 2. ...Benbuta, 3. ···valve seat,
4. Valve body part, 5. ... spindle, 6. ...
Spindle screw, 7. ...screw bush, 8. ...
Piston cylinder body, 9. ...Cylinder hole, 10. . . . Gap portion 11, . . . Seal member, 12. . . . Piston end portion 13, . . Valve box flange portion, 14. ...Valve lid flange, 15. ...Seal member flange, 16.・・・
・Handle, a, ... inlet channel, b, ...
outlet flow path. half 11 concave

Claims (1)

[Claims] 1. In a lift valve device equipped with a piston for balancing the valve thrust, a soft rubber-like elastic material with a thickness that does not overlap in the piston chamber (b) on the side where higher pressure acts on the piston. A sealing member (11) made of a substance is provided between the piston end (12), the outer peripheral surface of the piston cylinder (8), and the cylinder hole (9).
A lift valve device characterized in that a gap (10) formed between an end edge of an inner wall surface and an outer circumferential surface of a piston cylinder (8) is configured in a shape that isolates it from the piston chamber (b) side. .