US3554207A

US3554207A - Fluid switching device

Info

Publication number: US3554207A
Authority: US
Inventors: Robert Thomas John Skinner
Original assignee: Lucas Industries Ltd
Current assignee: ZF International UK Ltd
Priority date: 1968-05-08
Filing date: 1968-05-08
Publication date: 1971-01-12
Anticipated expiration: 1988-01-12

Abstract

A device comprising a first nozzle having an interior chamber, a pair of inlet passages communicating with the chamber through tangential portions thereof, and a recovery nozzle, the form of the jet issuing from the first nozzle being dependent upon the pressures of the inlets and only when they are equal is there a laminar stream issuing for reception in the recovery nozzle.

Description

United States Patent 2 Inventor Robert Thomas John Skinner I 3,272,213 9/1966 Jones 137/815 Kenilworth, England 3,272,215 9/1966 Bjornsen eta 137/815 21 Appl, No. 727,581- 3,285,263 11/1966 Bjornsen m1 l37/8l.5 [22] Filed May 8,1968 3,413,995 12/1968 Bowles et al l37/81.5 [45] Patented Jan. 12, 1971 v 3,426,534 2/1969 Murphy 137/81.5X [73] 'Asslgnee Joseqh L gndustsles) Limited Primary ExaminerSamuel Scott Birmmg Attorney-Holman & Stern [54] FLUID SWITCHING DEVICE 2 Claims, 5 Drawing Figs. I 52 u.s.c1.... 137/815 ABSTRACT: A device comprising a first nozzle having an i 1 llll- C| Flsc 16 terior chamber, a pair of inlet passages communicating with [50] Field of Search the chamber through tangential portions thereof, and a recovery nozzle, the form of the jet issuing from the first noz- 1 References c'ted zle being dependent upon the pressures of the inlets and only UNITED STATES PATE T when they are equal is there a laminar stream issuing for 3,256,899 6/1966 Dexter et a1. 137/8l.5 reception in the recovery nozzle.

PATENTEU JAN I 2m INVEN'TO R Shh/wt B 4M, ATTORNEYS FLUID SWITCHING DEVICE the first nozzle having an interior chamber, tangentially arranged passages disposed in-at least one oppositely directed pair along which streams of fluid flow from the two sources of fluids entering the chamber from the two sources along the oppositely arranged passages are equal, any tendency for rotation of the fluid about the axisv of the; chamber will be prevented thus causing fluid to be emitted in a lamina stream of a form to be received by the. recovery noule, and if the pressures are unequal, there will be rotation within the chamber resulting in the emission of the fluid as a substantially hollow cone which will affect the reception at the recovery nozzle.

The invention will now be described. by way of example with reference to the accompanying drawings in which:

FIG. 1 is a cross-sectional view of a device constructed in accordance with the invention; and I V FIG. 2 is a cross-sectional view on the line 2-2 in FIG. 1;

FIG. 3 is a diagrammatic representation of an alternative form of the device on a reduced scale; v

a FIG. 4 is a cross-sectional view on a reduced scale of a further alternative arrangement; and

FIG. 5 is a cross-sectional viewofa further form of the first nozzle in FIG. 1. a ,1

With reference to FIGS. 1 and .2 there is provided a first nozzle having an outlet 11 arranged in alignment with an entry opening 12 of a recovery nozzle 13- The nozzles 10 and 13 are disposed in a body 9 which is. provided with a drain passage 14. The recovery nozzle 13 is -a simple nozzle with a coaxial outlet passage 13a. 1

The first nozzle 10 has a pair of inlets 15, 16, the former being annular and surrounding the latter. There is, in the interior of the first nozzle 10, a chamber 17 which in this example has a frustoconical midregion, the wider end being formed as a cylindrical portion and the narrower end being formed by the cylindrical outlet 11. The inlets 15, 1.6 communicate with the interior of the chamber 17 at the wider end through two pairs of passages 18, 19. The terminal regions of these passages 18, 19 adjacent to the chamber 17 are formed tangentially with respect to the cylindrical portion of the chamber 17, each passage 18 being arranged in opposition to an associated passage 19 as illustrated in FIG. 2.

The arrangement is such that if fluid is supplied to both inlets 15, 16 of the first nozzle 10 simultaneously there will be created in the chamber 17 a flow which will be'emitted as a stream through the outlet 11 in the direction of the recovery nozzle 13. If the pressures in the inlets l5, 16 are equal, there will be no tendency for the fluid inthe chamber 17 to rotate about the axis of the nozzle 10, and accordingly, the emitted stream will be substantially cylindrical and lamina and a substantial proportion ofthis will therefore be received in the recovery nozzle 13. If, however, the pressures in the inlets I5, 16 are unequal, there will be a tendency for the fluid to rotate inside the chamber 17, and it will thus be emitted as a substantially hollow cone of an angle such that there will be no appreciable recovery of the fluid in the nozzle 13. These alternative flow patterns are illustrated in FIG. 1.

In an alternative arrangement, there are only two passages I8, 19 disposed as one pair of opposed tangentially arranged passages. I

With reference to the construction illustrated in FIG. 3.

there are provided two nozzles 20, each of the kind identified by numeral 10in FIG. 1, having respective outlets 21 disposed lustrated) and the arrangement is such that flow can take place either from right or left, or from left to right as illustrated in the drawings, and control can be achieved in whichever direction is chosen.

In the example illustrated in FIG. 4, there is provided a nozzle 23 having an outlet 24 and a generally frustoconical chamber 25, similar to the chamber 17 of the FIG. I construc tion, but there are three

separate inlets

26, 27 and 28, the former two being annular and surrounding the latter.

The inlets 26, 27 communicate through passages 29, 30

. with the chamber 25 through tangential passages as illustrated in FIGS. 1 and 2, but additionally, a continuous supply of fluid reaches the chamber 25 through the inlet 28.

In use, if only the inlet 28 is supplied with fluid, there will be emitted a substantially cylindrical and laminastrearn of fluid which can be received in a recovery nozzle (not illustrated), but if either of the inlets 26 or 27 is also supplied with fluid, the flow pattern will be disturbed and conical flow will take place so that recovery in a recovery nozzle is substantially prevented. Such conical flow pattern will be produced if only one of the inlets 26 or 27 is in use, or alternatively, if both are in use with the pressures therein unequal. Conditions for recovery in a recovery nozzle will, however be achieved when both the inlets 26 and 27 are being supplied at equal pressures.

In the FIG. 5 construction the nozzle 31 shown is to replace the first nozzle 10 of FIG. 1 and differs from it only in that the chamber 32 within it has a stepped cylindrical outlet of which the separate cylindrical portions are identified by

numerals

33 and 34 respectively. The larger diameter portion 34 is nearer to the frustoconical portion and is of equal diameter to the smaller end thereof.

With nozzles of the kind described accurate control of the outlet from the first nozzle can be achieved and, for example, if the average pressures in the nozzle are in the region of 1,000 pounds per square inch, a change in only l5 pounds per square inch suffices to change the flow pattern to affect control The degree of change in flow pattern between the two extremes, is however, dependent upon the relative pressures, in this small pressure range.

The recovery nozzle may be connected in a passage in which a fluid flow or pressure signal is required in accordance with the inlet pressures.

The devices may be used with either liquids or gases.

I claim:

1. A device comprising a first nozzle to which fluid can be supplied under pressure simultaneously from two independent sources, and a recovery nozzle aligned with said first nozzle, the first nozzle having a coaxial interior chamber, passages communicating with the chamber, tangentially thereof, said passages being arranged in two oppositely directed pairs, one of each pair being connected to the two sources respectively, the recovery nozzle being arranged to receive fluid emitted from the first nozzle when such fluid is emitted in a laminar stream, when the pressures of fluid in the two pairs of passages are equal, and the recovery nozzle being arranged to receive a smaller proportion of the flow when theemission is in the form of a substantially hollow cone, when the pressure of fluid in the two pairs of passages are unequal.

2. A device as claimed in claim 11 inwhich the recovery nozzle is the same as the first nonle and'has an interior chamber and passages arranged to communicate with sources respectively, a

Claims

1. A device comprising a first nozzle to which fluid can be supplied under pressure simultaneously from two independent sources, and a recovery nozzle aligned with said first nozzle, the first nozzle having a coaxial interior chamber, passages communicating with the chamber, tangentially thereof, said passages being arranged in two oppositely directed pairs, one of each pair being connected to the Two sources respectively, the recovery nozzle being arranged to receive fluid emitted from the first nozzle when such fluid is emitted in a laminar stream, when the pressures of fluid in the two pairs of passages are equal, and the recovery nozzle being arranged to receive a smaller proportion of the flow when the emission is in the form of a substantially hollow cone, when the pressure of fluid in the two pairs of passages are unequal.

2. A device as claimed in claim 1 in which the recovery nozzle is the same as the first nozzle and has an interior chamber and passages arranged to communicate with sources respectively.