This invention pertains to the art of valves and more particularly to valves for use in high fluid pressure drop applications.
The invention is particularly applicable to situations wherein the fluid supply to a system is variable and at substantially higher pressures than the desired output pressures where it is particularly desired to obtain a constant rate of fluid output from the valve outlet. Although the invention will be described with specific reference to this particular environment, it will be appreciated by those skilled in the art that the invention has broader applications and may be employed in other environments for controlling high pressure fluid flow.
Prior valves of this general type, that is, valves for use in obtaining a constant rate of fluid flow at high input pressures generally varying from about 600 to 2500 psi have comprised what are normally termed labyrinth type valves. In such valves, the fluid is forced through a random labyrinth arrangement whereby the fluid is necessarily required to take a tortuous path as it flows from the fluid inlet toward the fluid outlet. This tortuous path has the effect of dissipating pressure as the fluid passes from the valve inlet toward the outlet. Regulation of this dissipation along such a tortuous path is made possible by a valve actuator or stem which facilitates altering the effective length of the path in order that the desired output flow may be obtained. Normally, the labyrinth arrangement in prior valves of this type has been formed integrally into either the valve body or the actuator stem which thus necessitates the use of undesired precise metal removal or etching techniques.
These precise machining or etching techniques require a substantial amount of additional valve manufacturing time and effort which, of course, add to production costs. Also, and from an operational standpoint, the labyrinth type structure employed in prior valves of this general type is such that foreign contaminants dispersed in the fluid have had a distinct tendency to partially or completely clog portions of the tortuous path. Such labyrinth clogging produces changes in valving characteristics so as to require constant monitoring and adjustment in order to obtain a desired constant output fluid flow rate. This generates additional maintenance difficulties.
The present invention contemplates a new and improved arrangement which overcomes the above described problems and others and provides a new valve for use in high pressure drop applications which is simple, economical, reliable, readily adaptable to use in a variety of applications in high pressure fluid environments and which provides simple means for altering the physical make-up of the labyrinth arrangement.
The principal object of the present invention is the provision of a new and improved labyrinth type valve for use in high pressure drop applications which is simple in both construction and operation.
Another object of the present invention is the provision of a new and improved labyrinth type valve for use in high pressure drop applications which may be employed to provide an accurate, constant rate of fluid flow output.
Another object of the present invention is the provision of a new and improved labyrinth type valve for use in high pressure drop applications which is simple to manufacture.
Still another object of the present invention is the provision of a new and improved labyrinth type valve for use in high pressure drop applications which is readily adapted for use in a plurality of fluid environments.
Still a further object of the present invention is the provision of a labyrinth type valve for use in high pressure drop applications which may be employed to provide a constant rate of fluid flow output over a wide range of pressures.
Yet another object of the present invention is the provision of a new and improved labyrinth type valve for use in high pressure drop applications wherein the physical characteristics of the labyrinth arrangement may be readily altered as may be desired for a particular valve application.