US3533427A

US3533427A - Fluid amplifier

Info

Publication number: US3533427A
Application number: US697793A
Authority: US
Inventors: Donald W Chapin
Original assignee: Garrett Corp
Current assignee: Garrett Corp
Priority date: 1968-01-15
Filing date: 1968-01-15
Publication date: 1970-10-13
Anticipated expiration: 1987-10-13
Also published as: GB1250402A; FR1603675A

Description

United States Patent Los Angeles, California a corporation of California [54] FLUID AMPLIFIER 7 Claims, 4 Drawing Figs.

[52] U.S.Cl 137/815, 137/612, 137/608 511 Int.Cl .3 Fl5c3/04 [50] FieldofSearch 137/815,

Adams 137/815 3,276,463 10/1966 Bowles 137/8 l .5 3,342,198 9/1967 Gr0eber.... 137/815 3,375,840 4/1968 Fox et a1. 137/815 3,406,701 10/1968 Meulendyk.... 137/83 3,435,837 4/1969 Sher 137/815 Primary ExaminerSamuel Scott Attorney-Herschel C. Omohundro and H. Vincent Harsha direction and extent of deflection thereof and direct it to output passages. Relative adjustment of the sections serves to [56] References Cited change the relation of the receivers and the power stream to UNITED STATE PATENT counteract or modify the effect of the control streams. Such 3,053,276 9/ 1962 Woodward 137/815 adjustment may be made manually, mechani lly, pn m i- 3,17l,915 3/1965 Johnson l37/83X cally, or in any suitable manner to match, compare, or modify 3,233,622 2/1966 Boothe 137/815 signals from a variety of sources.

IO 33 35 I2 2| Patented Oct. 13, 1910 v 3,533,427

IO 33 u 2| I 35 !/4| I2 7 I3 I6 v I I ll 4 p 24 33 25 2 INVENTOR 56/ DONALD w. CHAPIN -I ATTORNEY FLUID AMPLIFIER SUMMARY This invention relates generally to the fluid control art and pertains more particularly to components employed in fluid 'control systems and designated as fluid amplifiers. More specifically, the invention is directed to improvements in a deflected beam type of fluid amplifier. Beam amplifiers in general use have a body with a reaction chamber into which fluid under pressure is directed to form a power stream which flows across the chamber and, in the absence of other conditions, is vented to exhaust.

To make use of the stream, the body is provided with one or more control nozzles at the sides of the reaction chamber to direct control streams against the power stream to deflect it toward one of a plurality of receivers which collects a variable proportion of the power stream and directs it to an output port for transfer to a point of use.

It is an object of this invention to so construct a beam deflector amplifier that its uses will be increased to include the ability to match, compare and/or modify a plurality of signals from different sources.

Another object of this invention is to provide a fluid amplifier having a plurality of relatively movable parts which combine to form a means for receiving and converting fluid under pressure into a power stream, to apply fluid under differential pressures to the power stream to variably deflect it, to form receivers to collect different proportions of the power stream,

depending upon the degree of deflection thereof, and to adjust the receivers to further vary the proportions of the power stream collected in any set degree of deflection of such power stream. The device may thus match, compare and/or modify signals from a plurality of sources, or provide a feedback effect from a mechanism operated in response to signals from the device.

A further object of the invention is to provide apparatus for matching, comparing and/or modifying fluid pressure signals and mechanical movements of elements controlled by or in response to fluid pressures.

Other objects and advantages of the invention will be made apparent by the following description of one fonn of the invention selected for illustration in the accompanying drawings.

THE DRAWINGS FIG. 1 is a schematic view ofa portion of a fluid system employing a fluid amplifier embodying the principles of the invention;

FIG. 2 is a similar view of another adaptation of the invention;

FIG. 3 is a plan view of a fluid amplifier formed in accordance with invention; and

FIG. 4 is a sectional view taken through the amplifier on the plane indicated by the line IV-IV of FIG. 3.

DESCRIPTION Specific reference to FIG. 1 discloses that a fluid amplifier 10 embodying the fundamental principles of the invention may be used in a fluid control system 11, a portion of which has been illustrated in this figure. The portion of the system 11 illustrated further includes a second fluid amplifier 12, an actuator 13 of the diaphragm type, and fluid conductors. The purpose of the portion of the system shown may be to maintain an object 14 connected with the push rod 15 of the actuator 13 in a predetermined position. As pointed out above, the actuator 13 is of the diaphragm type in which the casing 16 is divided into two sections 17 and 18 by a diaphragm 20.

Output lines

21 and 22 lead to the chamber sections 17 and 18, respectively, from output ports of a conventional fluid amplifier 12. Fluid under suitable pressure is supplied from a source 24 to the inlet of the second amplifier 12 to form a power stream 25.

Control fluid jets

26 and 27 direct control streams against the sides of the power stream to deflect it toward one or the other of the receivers 28, 29 communicating with the

lines

21 and 22, respectively.

The direction and extent of deflection of the power stream 25 depends upon the differential pressure of fluid supplied to the

jets

26 and 27 which communicate, respectively, with

output ports

31 and 32 of the amplifier 10 via

passages

33 and 34. Amplifier 10 includes first and second parts 35 and 36, the former having an inlet 37 receiving fluid from a pressure source 38 and directing it from a nozzle 40 toward the part 36. This latter part is formed with a receiver opening 41, 42 at each side of a wedgelike splitter vane 43 normally in axial alignment with the nozzle 40. The receiver openings 41 and 42 communicate with the

passages

33 and 34, respectively. These passages are at least partly formed in flexible material to permit movement of the part 36 relative to the part 35. Suitable mounting means, such as a pivot, is provided for part 36 to allow this relative movement. The arrangement of parts 35 and 36 is such that the movement of one with respect to the other will vary the angular relation of the

receiver openings

41 and 42 to the nozzle 40 and power stream issuing therefrom. This change in angle will vary the proportion of power stream fluid received by the

openings

41 and 42 and consequently the pressures in the

output passages

33 and 34. As indicated above, such pressure differential will deflect power stream 25, causing the application of different pressures to opposite sides of diaphragm 20 and a consequent tendency to transmit movement to element 14 via push rod 15.

In the system shown in FIG. 1, a feedback lever 44 has a connection 45 with the rod 15 and is pivoted to a suitable support, as at 46. An intermediate point 47 is connected by a link 48 with the part 36 of amplifier 10, as at 50. When the vane 43 is axially aligned with the nozzle 40, equal proportions of the power stream will be collected by the

receiver openings

41 and 42 and equal pressures will be transmitted to opposite sides of diaphragm 20 which will then tend to maintain the position of the element 14. It will be apparent that any tendency of the element 14 to move or be moved will cause a resultant movement of the part 36 through lever 44 and link 48 and the proportion of the power stream collected by

receiver openings

41 and 42 will be varied. A consequent control signal will be applied through the

jet nozzles

26, 27 to the power stream 25 to direct a counteracting pressure through

passages

21, 22 to the diaphragm 20. The element 14 will thus be returned to or held in its predetermined position.

In the control system shown in FIG. 2, a fluid amplifier 10A, having features in addition to those of amplifier 10, is employed. As in the device 10, this modified amplifier 10A has first and second relatively

movable parts

51 and 52, the former having an inlet 53 which communicates with a source 54 of fluid pressure and a nozzle 55. The amplifier 10A is shown more in detail in FIGS. 3 and 4.

The nozzle 55 converts fluid under pressure into a power stream directed toward the second amplifier part 52 which, in the illustration shown, is pivoted as at 56 for swinging movement relative to the first part 51. Under normal or inactive condition, part 52 is disposed with a wedgelike splitter vane 57 in axial alignment with the nozzle 55 which serves to divide the power stream issuing from the nozzle into equal portions for reception by the

receiver openings

58 and 59. Part 51 is provided at either side of nozzle 55 with

control jet nozzles

61 and 62 which may direct control streams against the sides of the power stream to deflect it to one side or the other, depending upon which of

nozzles

61 or 62 is receiving fluid at higher pressure. Suitable means, such as adjusting screws 63, may be employed to move part 52 relative to part 51 to vary the angular relation of the

receiver openings

58 and 59 to the nozzle 55 or power stream issuing therefrom. As in the form of the invention first described, a change in the angular position of the

openings

58 and 59 relative to nozzle 55 will vary the proportion of fluid from the power stream received thereby and

output passages

64 and 65 leading from

openings

58 and 59, respectively, will then convey fluid under differential pressures.

The

controljet nozzles

61 and 62 may be connected with a source or sources of fluid at different pressures whereby control signals will be transmitted to the amplifier A. FIG. 2 depicts one example of use of the mechanismv In this figure the system embodying the amplifier is utilized to control the operation of a pressure regulating valve 66 disposed in a fluid line 67 leading from a source (not shown) of fluid pressure. The valve 66 has a piston and cylinder-type actuator 68 operatively connected thereto by a push rod 70. A conventional fluid amplifier 71 is connected in the system between the amplifier 10A and the actuator 68.

Amplifier 71 receives fluid under pressure from a source 72 g and converts it into a power stream 73, which is deflected by control signals from passages 64lor 65 into one or the

other receiver

74, 75 which communicate with opposite ends of the actuator cylinder 68 via

lines

76 and 77, respectively. In the operation of the system of FIG. 2, the adjusting screws 63 may be actuated to set part 52 in a position in which a greater proportion of the power stream from nozzle 55 will be received by opening 58 and passage 64 will apply a control jet stream to the power stream 73 to deflect it toward receiver 75 which will then receive a greater proportion of the power stream. This increased portion of the fluid from the power stream will be conducted by line 77 to the actuator cylinder and cause the piston to transmit opening movement to the valve 66. As this valve opens, fluid will flow through the passage 67 on the downstream side of the valve 66 and pressure'will increase in this portion of the passage 67. This increase in pressure will cause a flow offluid through a line 78 leading from passage 67 to control jet nozzle 61 in part 51 of the amplifier 10A. A control stream of fluid will then be directed against the power stream flowing from nozzle 55 and the power stream will be deflected away from opening 58 to decrease the proportion of fluid received thereby and increase the fluid collected by receiver 59. This action will tend to interrupt or reverse the operation of the valve actuator 68. It is intended that the control will function substantially simultaneously with the operation of the valve and thus prevent the flow of excess fluid past the valve with consequent overrun of pressure. lf, however, an undesired pressure increase downstream of the valve should occur due to excessive valve movement or a reduction in requirement of the regulated pressure, the power stream will be deflected far enough away from opening 58 and toward opening 59 to effect reverse operation of the actuator 68. Valve 66 will then be moved toward a closed position. In this manner valve 66 may be actuated to modulate pressure in passage 67 downstream of the valve.

From the foregoing, it will be apparent that a fluid amplifier has been provided which is capable of performing a plurality of functions, such as comparing one fluid pressure with another, or fluid pressures with mechanical movements, or predetermined positions thereof which serve as points of reference.

lclaim:

l. A fluid amplifier comprising:

a. a first means providing a stationary nozzle for converting fluid under pressure into a power jet stream; and

b. a second means disposed for controlled pivotal adjustment relative to said nozzle about an axis adjacent said nozzle and extending through the axis thereof, said second means having an opening therein for receiving fluid from said power jet stream and directing it to an out put passage, adjustment of said second means relative to said first means varying the proportion of said power jet stream received by said opening.

2. A fluid amplifier as set forth in claim 1 in which said first means has a control jet nozzle at one side of said power jet stream noule and operative to direct a control jet stream against the power jet stream to deflect the same laterally.

3. A fluid amplifier as set forth in claim 1 in which said second means is piv'otally adjustable relative to said first means about an axis intersecting that of said nozzle.

4. A fluid amplifier as set forth in claim 1 in which said second means has a plurality of receiver openings for fluid from said power et stream, the ad ustment of said second means varying the angular relation between said power jet stream nozzle and said receiver openings.

5. A fluid amplifier as set forth in claim 4 in which said first means has a control jet nozzle at either side of said power jet stream nozzle, said control jet nozzles being operative to direct control jet streams against opposite sides of the power jet stream to deflect the same laterally.

6. A fluid amplifier as set forth in claim 5 in which said second means has a flow splitter between a pair of receivers, said flow splitter being aligned with said power jet stream nozzle when the angular relation between said power jet stream nozzle and each of said receivers is equal.

7. A fluid amplifier as set forth in claim 5 in which said second means is adjustable about an axis disposed on and normal to the axis of said power jet stream nozzle.