Fluid handling – Line condition change responsive valves – Pilot or servo controlled
Patent
1996-01-23
1998-04-07
Hepperle, Stephen M.
Fluid handling
Line condition change responsive valves
Pilot or servo controlled
1374895, 1374925, F16K 1722
Patent
active
057353085
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to an automatic constant-pressure regulating lift valve with automatic flow restriction regulating passage, to be installed in a liquid transportation line, capable of being conveniently used for water conveyance and water distribution, requiring little trouble for management, omitting all fixed flow restriction regulating passages including needle valves from a pilot valve so that the valve can be easily constructed in large dimensions and can be used under high-pressure, said lift valve being provided with valve structures having valve elements capable of automatically moving away from the corresponding valve seats for automatic cleaning when the valve structures are clogged.
In this specification, "water" is the general term for liquids.
BACKGROUND ART
A conventional automatic regulating lift valve widely used for automatically regulating the pressure of a liquid being transported through a line is provided with a pilot valve that detects the valve-outlet pressure of a liquid in the outlet, and operates a piston or a diaphragm for driving a main valve unit by a pilot valve unit operated by restricting the flow of the liquid with a fixed flow restriction regulating line, such as a needle valve.
Although the theoretical performance of such a conventional automatic regulating lift valve has been favorably evaluated, when practically using the automatic regulating lift valve, anxiety about difficulties in maintenance and management, and durability is unavoidable. For example, a conventional valve of a structure shown in FIG. 4 has the following two problems which are difficult to solve.
(1) A sealing member 6s attached to the periphery of a main valve driving member 6 in contact with a cylindrical wall 8 must be capable of perfect watertight sealing to prevent leakage of the liquid when a main valve unit is shut off. Therefore various sealing means have been tested and a bellows or a diaphragm is employed as the sealing member 6s for perfect watertight sealing. However, such a conventional valve, when formed in large dimensions or for handling high-pressure liquid, is not free from problems in the durability of the sealing member and from problems in machining accuracy and still involves troublesome maintenance work.
(2) Although the main valve unit must be driven moderately to avoid the hunting of the pressure due to rapid flow control operation, the conventional valve provided with a pilot valve unit disposed in a connecting passage Q connected to an outlet passage c in which a valve-outlet pressure prevails needs a flow restriction regulating valve S, such as a needle valve, in a connecting passage P. This fine fixed passage is liable to be clogged with sand grains and dust, causing troubles. Therefore, the conventional valve needs a strainer or the like, and a general-purpose pressure reducing valve, particularly, a large general-purpose pressure reducing valve for high-pressure liquid, is difficult to use except when the pressure reducing valve is applied to handling clean water.
DISCLOSURE OF THE INVENTION
The present invention provides an automatic constant-pressure lift valve solving those problems in the conventional valves, provided with a pilot valve unit not provided with any fixed flow restriction regulating passage, protected from clogging and having a construction that does not leak water when the main valve unit is shut off and is capable of continuously regulating the valve-outlet pressure at a desired level.
An automatic constant-pressure lift valve in accordance with the present invention, as will be apparent from the following description of preferred embodiments thereof, comprises a main valve opening pilot valve A (hereinafter referred to as "A valve unit") that operates for opening when the valve-outlet pressure drops below the predetermined level, and a main valve closing pilot valve B (hereinafter referred to as "B valve unit") that operates for opening when the valve-outlet pressure increases beyond the predetermined level. These
REFERENCES:
patent: 583269 (1897-05-01), Sellew
patent: 1000729 (1911-08-01), Gloeckler
patent: 4972870 (1990-11-01), Changnian et al.
Yokota Hiroshi
Yokota Shingo
Hepperle Stephen M.
Kabushiki Kaisha Yokota Seisakusho
LandOfFree
Automatic constant-pressure regulating lift device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Automatic constant-pressure regulating lift device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Automatic constant-pressure regulating lift device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-5548