US3563260A

US3563260A - Power transmission

Info

Publication number: US3563260A
Authority: US
Inventors: Gaylord O Ellis
Original assignee: Sperry Rand Corp
Current assignee: Vickers Inc
Priority date: 1968-11-08
Filing date: 1968-11-08
Publication date: 1971-02-16
Anticipated expiration: 1988-02-16
Also published as: DE1955973B2; DE1955973A1; FR2022857A1; GB1290547A; JPS4827878B1

Abstract

A vortex flow control device having a chamber with a main stream input flowing radially inward during one mode of operation and flowing in a logarithmic spiral path during a second mode of operation for creating a back pressure for a metering element which is inversely proportional to the flow rate of the fluid issuing from said metering element.

Description

United States Patent inventor Appl. No.

Filed Patented Assignee Gaylord 0. Ellis Rochester, Mich.

Nov. 8,1968 Feb. 16, 1971 Sperry Rand Corporation Troy, Mich.

a corporation of Delaware POWER TRANSMISSION 11 Claims, 5 Drawing Figs.

US. Cl Int. Cl Field of Search 137/8l.5 Fl5c 1/16 137/8 1 .5

References Cited UNITED STATES PATENTS Bowles Lorenz Adams et a1. Rhoades Bowles et al Primary Examiner-Samuel Scott Attorney-Van Meter and George l37/8l.5X I37/81.5X 137/815 137/81.5X 137/815 ABSTRACT: A vortex flow control device having a chamber with a main stream input flowing radially inward during one mode of operation and flowing in a logarithmic spiral path during a second mode of operation for creating a back pressure for a metering element which is inversely proportional to the flow rate of the fluid issuing from said metering element.

PATENTEUFEBIBIBYI 35633260 SHEI1UF3 FIG III I MM'HI; m \ks INVENTOR. l-Q D O. ELLIS ATTORNEYS sum 2 [IF 3 5mm W5 INVENTUR.

' ATTORNEYS PATENTEDFEBIB'IBIIL' 3.563.260

sumanra FIG. 5"

INVIL'N'H )R. GAYLORD o. ELLIS ATTORNEYS 1 rows: TRANSMISSION BACKGROUND OF THE INVENTION The present invention relates to flowcontrol devices of the type which do not utilize mechanical flow impeding means and, more particularly, this inventionrelates to vortex flow control devices.

It has been established that, in valves of the metering element type, bubbles are formed in the jet stream issuing from the metering element, if the dynamic'head of the jet exceeds some critical value, generally three times the back pressure. This bubble formation generates noise and fluid cavitation which may result in damage to the valve and a shortening of its useful life.

This problem of bubble formation becomes increasingly serious as system pressures increase and water soluble oil solutions are used as an operating fluid.

One solution is to provide an increased back pressure at critical conditions of valve operation wherein the issuing jet stream has a dynamic head which will be less than three times the back pressure. This may be accomplished by means of a simple restriction, however, such restrictions provide a back pressure which increases with flow, thus, giving the required back pressure at high flow conditions where it is generally not needed and results in an unnecessary reduction in system efficiency. It would thus be desirable to provide a restriction which will vary inversely with the flow rate; that is, a restriction which will provide a high back pressure at low flow rates and which will provide a low back pressure at high flow rates. Such a restriction may be had by utilizing a vortex flow control device.

The basic vortex flow control deviceis comparatively simple in construction consisting generally of a cup-shaped chamber in which the main fluid stream is introduced at the outer wall of the chamber'and is oriented, to flow radially inward to the center of the chamber to an outlet. The control input port is located near the power input stream and thecontrol flow is directed perpendicularly against the main fluid supply. If no control input is present, themain fluid stream flows directly to the output, and encounters minimum impedance. When a control flow is introduced, the interaction of .the main and control streams results in the main stream being deflected away from its radial path to establish a spiral pattern. This deflection of the mainstream and subsequent formation of the vortex lengthens the flow path of the main fluid stream, which increases the pressure drop. If the control stream is sufficiently strong, the main flow'stream can be shut off completely. The ratio of themaximum discharge flow divided by the minimum discharge flow is known as the turndown ratio and generally is on the order of 6 to 1. However, to be generally practical in reducing bubble formation within a metering element, a vortex flow control device should have a turndown ratio of to l, or more.

It should also be noted that the control stream is at a higher pressure than that of the main flow stream, thus requiring a separate source of fluid pressure energy which adds unnecessary cost to such a system. It would thus be very desirable to provide a vortex flow control device having a turndown ratio of 20 to l or more and one which may function without the need for a high-pressure control stream.

SUMMARY OF THE INVENTION A vortex flow control device havlng a chamber with a main stream input at its periphery which is adapted to flow radially inward to an output; a plurality of logarithmic spiral elements forming a flow path originating at the main stream input and terminating at the output; and, means for selectively directing the main stream from its radial flow path to the spiral flow path.

It is therefore an object of this invention to provide an improved vortex flow control device.

It is another object of this invention to provide an improved vortex flow control device having a turndown ratio which greatly exceeds values hereinbefore obtainable.

It is another object of this invention to provide an improved vortex flow control device which is operable with a control input having a pressure either above or below the main flow stream pressure.

It is still another object of this invention to provide an improved vortex flow control device which is capable of providing a back pressure for use with a metering element to eliminate bubble formation in the jet issuing from said element.

It is a further object to provide an improved vortex fluid control device having all of the above cited advantages and which requires no moving mechanical elements.

Further objects and advantages of the present invention will become apparent from the following description, reference being made therein to the accompanying drawings wherein a preferred form of the present invention is clearly shown.

IN THE DRAWINGS FIG. 1 is a sectional view of a vortex flow control device embodying the present invention and taken along line 1-1 of FIG.

present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the several figures, and especially FIG. 1, there is shown a presently preferred, but merely illustrative embodiment of the inventive principles; a flow control device 10 of the vortex type. The housing 12 of the device comprises a nozzle plate 14 sandwiched between a body section 16 and an end plate 20, all of which are suitably connected to each other by means of bolts 22. A mounting flange is provided at 24 and is secured to the end plate 20 by bolts 26 one of which is shown in FIG. 1. The body section 16 is provided with an inlet connection port 28 having an inlet passage 30 leading therefrom into a cylindrically shaped cavity 32. The inlet port 28 is adapted to be connected to a source of fluid pressure energy, such as a pump, not shown.

Within the cavity 32, there is provided a vortex control element 34 having at its outer periphery a plurality of axially extending flanges 36 of which the opposite ends 38 and 40 respectively abut the cavity wall 42 and the nozzle plate 14 and is secured therein the the same, forming a second cavity or chamber 43 between the control element 34 and the nozzle plate 14. The vortex control element. is further provided with a guide cone 44 located within chamber 43 at its center on a vortex flow surface 46 formed on the right-hand side of element 34. The cone 44 extends axially away from surface 46 into a throat 48 of conically shaped outlet nozzle 50. The outlet nozzle 50 is formed within a centrally located axial extension 51 of the nozzle plate 14 and extends through a bore 52 formed within the end plate 20.

Within the end plate 20, there is provided an annular recess 54 which is connected by means of passageway 56 to a control pressure input connection port 58 for the purpose of conducting the control fluid in a manner to be described hereinafter.

Seal 60 is provided to prevent leakage at the juncture of the body section and the nozzle plate while

seals

62 and 64 are provided to prevent leakage at the juncture of the nozzle plate and end plate. The

seals

60, 62, and 64 are preferably in the form of an endless elastomeric O-ring of circular radial cross section, however, any suitable sealing means may be employed.

Referring now to FIG. 3 where there is illustrated the vortex flow surface 46 of the control element 34. At the outer peripheral wall of the surface 46 and circumferentially spaced between the flanges 36 are a plurality of slots indicated by the numerals 66 through inclusive. Each, slot connects the cavity 32 with the flow surface 46. Associated with each slot 66 through 80, respectively are radial flow paths 82 through 96 inclusive. through which the fluid will flow from the slots to the outlet nozzle, until acted on m a manner to be described hereinafter. Thus, it can be seen that a continuous flow path is established between the inlet connection and the outlet nozzle by means of the cavity 32, the peripheral slots 66 through 80, the radial flow paths 82 through 96, the guide cone 44, and throat 48 There is provided on the vortex flow surface 46 a plurality of radially spaced blades or vane elements 100 following a logarithmic spiral curve. The vane elements 100 form a plurality of logarithmic spiral flow paths 101 through which the radial flow paths 82 through 96 intersect and annularly separate. The spiral angle [3 is that angle of the blade formed at the intersection of a radius of the vortex surface 46 and a line which is tangented to the blade 100 and the angle B will be a constant along the same logarithmic spiral. As a quantity of fluid moves from one point to another point along the spiral flow path, that is, its annular movement 6 to that quantity will move inward from one distance y, from the vortex center to a second position at y The several functions are related by the following formula:

Tan 6=% The logarithmic spiral may be of any desired angle; the greater the logarithmic spiral angle, the greater the turndown ratio will be and vice versa. Although the vane elements are illustrated as being stationary, it would also be possible to incorporate the vane elements whose logarithmic angle could be varied.

There is associated with each of the radial flow paths 82 through 96 respectively, a plurality of control jets 102 through 116 inclusive. The control jets are generally perpendicular to the radial flow paths and each individually are connected to the annular recess 54 within the end plate by means of a plurality of bores 118 extending from the vortex control element 34 and through the nozzle plate 14, one of which is illustrated in FIG. 1. It can be seen from FIG. 3 that the control jets are positioned on the control element 34 in such a manner that the control flow admitted from the jets will flow in the direction of the logarithmic spiral vane elements and into the spiral flow paths 101.

In operation, as hereinbefore mentioned, fluid enters the device by means of the inlet connection port; flows therethrough to the cavity 32, around the outer periphery of the control element via the slots, and undisturbed radially inward to the cone, and is discharged into the conical nozzle. When high-pressure fluid enters the annular recess 54 via the control pressure input connection port, pressure fluid will be conducted through the bores 118 to each of the control jets and into each of the radial flow paths. The high-pressure flow from the jets gives a deflection to the main flow which, though slight, is sufficient to cause the main flow to partially engage the vane elements, which, in turn, further deflects the main flow until a logarithmic spiral flow path is established. Flow diverted from one radial flow path into the spiral flow path will further deflect the main flow within other radial flow paths as it follows the desired spiral path, thus further aiding the action of the vortex.

The embodiment illustrated in FIG. 4 with the exception of the location of the control jets, is identical to that illustrated in FIG. 3, and thus, the corresponding components will be identified with the same numeral followed by the letter a. For example, the vane elements in FIG. 3 are identified by the numeral 100, whereas in FIG. 4, they are identified by the numeral 100a.

The control jets 102a through 166a are positioned on the control element 34a in such a manner that the jets are generally faced in a direction which is opposite to the spiral flow path, but are still generally normal to the radial flow paths. The plurality of control jets are connected to a lowpressure bleed, such as a vacuum pump, not shown.

In the operation of the embodiment illustrated in FIG. 4, the undisturbed fluid entering through the slots 66a through a will flow radially inward until the recess 54 is bleed vented to a low-pressure region. When vented, the mainflow within the radial flow paths will attach to the walls of the vortex chamber with an accompanying deflection. Once deflected slightly, the main flow will engage the vane elements a which will further deflect the flow into the desired spiral flow path in the same manner as hereinbefore described the embodiment illustrated in FIG. 3.

Referring now, to the FIG. 5, for a schematic view of a system employing the present invention. A pump is provided for supplying fluid pressure via conduit 121 from a reservoir 122 to a fluid motor 124 via conduit 125. Pressure fluid is selectively directed to either

conduit

126 or 128 by means of a standard four-way valve 130 for the purpose of reciprocally moving a piston 132 to any desired position. For example, if fluid pressure is communicated to conduit 126, the piston 132 will reciprocate rightwardly and fluid will be discharged into conduit 128 and via the four-way valve into an outlet conduit 134. The fluid being discharged is carried by the conduit 134 to the vortex flow control device 136 and back to the reservoir 122. The control jets 138 of the vortex device are continuously connected to the pressure fluid being admitted from pump 120 by means of a conduit 140. Relief valve 142 is provided and in fluid communication with conduit 140 for the purpose of venting the fluid pressure directly to the reservoir when the pressure exceeds a predetermined value.

The vortex flow control device 136 which is schematically illustrated in FIG. 5 is identical in construction and operation to the vortex flow control device 10 described hereinbefore; therefore, the back pressure induced in conduit 134 will be a function of both the control flow and the main flow entering the vortex device 136. If a constant main flow enters the device and the control flow is varied, the back pressure induced in conduit 134 will increase with a corresponding increase in the control flow; whereas, if a constant control flow is utilized, the back pressure induced in the conduit 134 will decrease with an increase in the main flow. As illustrated in FIG. 5, the control flow is essentially at a fixed rate while the main flow in conduit 134 varies as the valve 130 is shifted from one position to another.

As valve 130 is initially shifted to provide fluid communication between

conduit

128 and 134, the main flow into the vortex device 136 will be relatively small as compared to the constant control flow at 138 with a resultant effect of inducing a back pressure in conduit 134 in a manner which has been described hereinbefore. As the valve 130 opens further, the main flow will increase, and the back pressure induced in conduit 134 will decrease. By proper design which will be dependent on the pressure range and fluid desired, the fluid being discharged into the reservoir via vortex device 136 will be maintained at some predetermined back pressure to prevent the formation of bubbles at the discharge of valve 130. It can readily be seen that the back pressure induced by means of the vortex device will be greater at the lower main flow rates and will decrease in value as the main flow rate is increased. This condition is considerably more desirable than the increased back pressure which would wear across a fixed restriction as the main flow rate is increased.

It can thus be seen that the present invention has provided a vortex flow control valve having no mechanical or moving parts, which is not prone to malfunction due to the presence of dirt or other materials in the fluid, and which will have a turndown ratio which will exceed values hereinbefore obtainable.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

I claim:

1. A vortex flow control device comprising:

A. Means forming a chamber having peripheral walls;

B. First means for supplying fluid to said chamber adjacent said peripheral walls and radially inward thereof;

C. Means remote from said peripheral walls for discharging fluid from said chamber;

D. A plurality of vane elements which follow a logarithmic spiral curve to form a spiral fluid flow path extending from said supply means to said discharge means; and

E. Means for diverting said radially inward fluid flow into said spiral fluid flow path.

2. A vortex flow control device as described in claim 1 wherein said diverting means comprises a control jet for supplying a control fluid substantially normal to the direction of said radially inward fluid flow for diverting said radially inward fluid flow into said spiral fluid flow path.

3. A vortex flow control device as described in claim 1 wherein said diverting means comprises a low pressure bleed associated with said radially inward flow for diverting said radial flow into said spiral fluid'flow path.

4. A vortex flow control device as described in claim 1 wherein said vane elements form a plurality of logarithmic spiral fluid flow paths each of which extends from said supply means to said discharge means.

5. A vortex flow control device as described in claim 4 wherein said supplying means comprises a plurality of fluid inlets associated with said peripheral walls; and, a plurality of radial flow paths extending from each of said fluid inlets to said discharge means.

6. A vortex flow control device as described in claim 5 wherein said diverting means comprises a plurality of control jets for individually supplying a control fluid substantially normal to the direction of each of said radially inward fluid flow paths for diverting said radially inward fluid flow into said spiral fluid flow paths.

7. A vortex flow control device as described in claim 6 wherein said diverting means comprises a plurality of low pressure bleeds individually associated with each of said radially inward fluid flow paths for diverting said radially inward fluid flow into said spiral fluid flow paths.

8. A vortex flow control device as described in claim 5 wherein said radial fluid flow paths project through said spiral fluid flow paths.

9. A vortex fluid flow control device for restraining the flow of pressure fluid comprising:

A. A housing having a fluid inlet and a fluid discharge;

B. A chamber having a plurality of slots formed about the peripheral wall of said chamber for forming a fluid connection between said fluid inlet and said chamber;

C. A flow path extending radially inward from each of said fluid slots to said discharge, said discharge being remote from said peripheral wall;

D. A plurality of vane elements defining a plurality of spiral flow paths each path extending along a logarithmic spiral curve for connecting said slots to said discharge; and

E. Means for diverting said radially inward fluid flow from said radial fluid flow paths to said spiral fluid flow paths.

10. A circuit for establishing fluid communication between a high pressure fluid region and a low pressure fluid region comprising:

A. A valve having an inlet connect-ed to said high pressure fluid region, an outlet, and means disposed between said inlet and outlet for providing a predetermined pressure drop between said inlet and said outlet; and

B. A vortex flow control device comprising: means forming a chamber having peripheral walls; means connecting said valve outlet to said chamber for supplying fluid to said chamber adjacent said peripheral walls, and radially inward thereof; means remote from said peripheral walls for discharging fluid to said low pressure fluid region; a plurality of vane elements defining a plurality a logarithmic spiral fluid flow paths extending from said peripheral walls to said discharge means; and, means for diverting said radially inwardly fluid flow into said spiral fluid flow paths. 1

11. A vortex flow control device as described in claim 10 wherein said diverting means comprises a plurality of fluid supply jets substantially normal to the direction of said radially inward fluid flow, said control fluid supply being connected to said high pressure fluid region.

Claims

1. A vortex flow control device comprising: A. Means forming a chamber having peripheral walls; B. First means for supplying fluid to said chamber adjacent said peripheral walls and radially inward thereof; C. Means remote from said peripheral walls for discharging fluid from said chamber; D. A plurality of vane elements which follow a logarithmic spiral curve to form a spiral fluid flow path extending from said supply means to said discharge means; and E. Means for diverting said radially inward fluid flow into said spiral fluid flow path.

3. A vortex flow control device as described in claim 1 wherein said diverting means comprises a low pressure bleed associated with said radially inward flow for diverting said radial flow into said spiral fluid flow path.

9. A vortex fluid flow control device for restraining the flow of pressure fluid comprising: A. A housing having a fluid inlet and a fluid discharge; B. A chamber having a plurality of slots formed about the peripheral wall of said chamber for forming a fluid connection between said fluid inlet and said chamber; C. A flow path extending radially inward from each of said fluid slots to said discharge, said discharge being remote from said peripheral wall; D. A plurality of vane elements defining a plurality of spiral flow pathS each path extending along a logarithmic spiral curve for connecting said slots to said discharge; and E. Means for diverting said radially inward fluid flow from said radial fluid flow paths to said spiral fluid flow paths.

10. A circuit for establishing fluid communication between a high pressure fluid region and a low pressure fluid region comprising: A. A valve having an inlet connected to said high pressure fluid region, an outlet, and means disposed between said inlet and outlet for providing a predetermined pressure drop between said inlet and said outlet; and B. A vortex flow control device comprising: means forming a chamber having peripheral walls; means connecting said valve outlet to said chamber for supplying fluid to said chamber adjacent said peripheral walls, and radially inward thereof; means remote from said peripheral walls for discharging fluid to said low pressure fluid region; a plurality of vane elements defining a plurality a logarithmic spiral fluid flow paths extending from said peripheral walls to said discharge means; and, means for diverting said radially inwardly fluid flow into said spiral fluid flow paths.