US3447553A

US3447553A - Pneumatic airfoil actuated amplifier

Info

Publication number: US3447553A
Application number: US584024A
Authority: US
Inventors: Carl J Campagnuolo; Leonard M Sieracki
Original assignee: US Department of Army
Current assignee: US Department of Army
Priority date: 1966-10-03
Filing date: 1966-10-03
Publication date: 1969-06-03
Anticipated expiration: 1986-06-03

Description

Jum 1969 c. J. CAMPAGNUOLO ETAL 3,447,553

PNEUMATIC AIRFOIL ACTUATED AMPLIFIER Filed Oct. 8,.1966 Sheet of 2 //VVEA/7'0,5, 6424 J. aM /zaA/uom [EU/V4,? Al. SIEF/ICK/ H- A mm June 3, 1969 c, CAMPAGNUQLO ET AL 3,447,553

PNEUMATIC AIRFOIL ACTUATED AMPLIFIER Filed Oct. 5. 1966 Sheet 2 of 2 i INVENTO/QS 0m J (AMPAGl/UOLO [Ed/VA/ZD/l S/EI/JCK/ W. a: m A-r roxugvs United States Patent U.S. Cl. 13781.5 11 Claims ABSTRACT OF THE DISCLOSURE A fluid amplifier having a left, right, and a single or plurality of centrally located output channels and wherein the power stream through the amplifier may be proportionally deflected to the central channels from either the left or right output channels independent of the deflection of the other output stream. Proportional control in the fluid amplifier is accomplished by placing an elongated airfoil symmetrically within the interaction chamber of the fluid amplifier with either its rounded or sharp edge adjacent to the power nozzle. Deflection is achieved by means of control streams flowing from either side of the symmetrically placed airfoil which emit fluid in a downstream direction of the power nozzle.

This invention relates to fluid amplifiers and more particularly to a fluid amplifier having multi-output channels.

In a typical fluid amplifier, an orifice at one end of an interaction chamber emits a power stream of fluid that flows in the general direction of two or more outlets at the other end of the chamber. One or more control streams of fluid emitted from control orifices at the sides of the chamber can be caused to impinge on the power stream and to divert the power stream from one outlet to another. As is well known, some fluid amplifiers are of a proportional type, in which the distribution of the power stream between outlets is continuously variable. Others are of the lockon or bistable type, in which the power stream, if initially locked onto a first sidewall that is part of a first outlet, continues to flow out the first outlet until sufiicient control nozzle energy is applied to detach the stream from the first sidewall. Thereupon, the stream abruptly switches to another sidewall and flows out of a second outlet. A typical fluid amplifier is symmetrical, having left and right control jets and left and right outlets separated by a divider.

An object of this invention is to provide a fluid amplifier that has at least three output channels and in which a part of the power stream may be variably deflected from one output channel to another output channel by means of a control stream.

Another object of this invention is to provide a fluid amplifier having left, right and center output channels in which a left output stream initially flowing out the left output channel may be proportionately deflected to the center output channel and in which a right output stream initially flowing out of the right output channel may be proportionately deflected to the center output channel, the deflecting of the right output stream being independent of the deflection of the left output stream.

Still another object of the invention is to provide a fluid amplifier having left center, right center, and right output channels in which a left output stream initially flowing out the left output channel may be proportionately deflected to the left center output channel and in which a right output stream initially flowing out the right output channel may be proportionately deflected to the right center output channel, the deflecting of the right output stream being independent of the deflecting of the left output stream.

A further object of the invention is to provide a fluid amplifier having left, left center, right center, and right output channels in which a left output stream initially flowing out the left center output channel may be proportionately deflected to the left output channel and in which a right output stream initially flowing out the right center output channel may be proportionately deflected to the right output channel, the deflecting of the right output stream being independent of the deflecting of the left output stream.

In an illustrative embodiment of the invention a fluid amplifier is symmetrically constructed with a power nozzle, an interaction chamber, a left output channel, a right output channel, and a center output channel, An elongated airfoil is symmetrically positioned in the interaction chamber of the fluid amplifier with its rounded edge adjacent the power nozzle. Left and right control tubes project from the left and right sides of the airfoil, respectively, and are pointed to emit fluid in a downstream direction of the power nozzle. In the absence of control flow from either control tube a power stream from the power nozzle is divided by the airfoil into a left output stream that flows out the left output channel and a right output stream that flows out a right outpu channel. Application of control flow to either control tube will entrain the corresponding output stream and cause the entrained stream to proportionately deflect to the center output channel.

In a second illustrative embodiment of the invention an airfoil is similarly placed in an interaction chamber. In the second embodiment of the invention, the sharp edge of the airfoil is placed adjacent the power nozzle. Control tubes are again placed on the left and right side of the airfoil. In the absence of control flow from either control tube a power stream from the power nozzle is divided by the sharp edge of the airfoil, attaches to the sides of the airfoil and issues from the center output .channel. A control flow to either control tube will proportionately deflect the power fluid on that side of the airfoil into the respective output channel. Application of control flow to both control tubes will cause power fluid to be proportionately deflected to both output channels.

These and other objects and aspects of the invention will be apparent to those skilled in thevart from the following disclosure and accompanying drawings in which:

FIG. 1 is a schematic illustration of one embodiment of the invention.

FIG. 2 is a schematic illustration of a modification of the embodiment of FIG. 1.

FIG. 3 is a schematic illustration of a second embodiment of the invention.

FIG. 4 is a schematic illustration of a modification of the embodiment of FIG. 3.

In FIG. 1, an amplifier 30 has a source of pressure 10 which by a conduit 11 and a power nozzle 12 communicates with an interaction chamber 28. A left sidewall 14 and a right sidewall 13 are adjacent power nozzle 12, but are each set back from the power nozzle by a small distance. Both sidewalls are preferably, but not necessarily straight, and both are symmetrical with respect to the power nozzle. Located symmetrically in interaction chamber 28 is a conventional symmetrical airfoil 15, which is positioned a short distance from power nozzle 12. A rounded leading edge 34 of the airfoil is bisected by the centerline of power nozzle 12.

Splitters

24 and 25 are adjacent trailing edge 20 of airfoil 15 and serve to define output a left output channel 23 and a right output channel 22. A center output channel 21 is formed between

splitters

24 and 25. 'A control port 32 in airfoil 15 is connected to a source of control pressure not shown and leads to a control tube 17, which is positioned along airfoil approximately one-third the chord length of the airfoil from the leading edge. Control tube 17 is positioned with respect to splitter 24 to direct control fluid into center output channel 21. A similar control port 33 and control tube 16 are located on right side 19 of airfoil 15.

In the absence of a fluid control signal from either

control tube

16 or 17, the power fluid sfrorn power nozzle 12 hits against rounded leading edge 34 of airfoil 15. The fluid is event y split by the rounded edge and is directed into left output channel 23 and right output channel 22.

If a control pressure is applied to port 32, control fluid will issue from tube 17 and enter center output channel 21, entraining power fluid to the left side of the airfoil and proportionately deflecting the power fluid to center output channel 21. The operation is reversible; if control pressure is stopped the stream on the left side of the airfoil is again deflected to channel 23 by the airfoil. A control pressure applied to port 33 will similary cause the power fluid on the right side of the airfoil to proportionately deflect from right output channel 22 to center output channel 21. The left-side and right-side operations are independent of each other. If the amount of control flow is increased, a greater amount of entrainment of the power fluid will occur, thus giving the amplifier an output proportionality.

FIG. 2 is identical to FIG. 1 with the addition of splitter 35 positioned with its apex in contact with trailing edge of airfoil 15. The splitter serves to further define center output channel 21 into a right center output channel 37 and a left center output channel 36. The addition of splitter 35 serves to give the amplifier plural output channels into which fluid may be selectively directed, thus increasing the uses the ampifier may be put to.

The operation of the amplifiers of FIGS. 1 and 2 is similar, the difference being that in FIG. 2 when power fluid is entarined by tube 17, it will be directed into left center output channel 36 instead of center output channel 21 of FIG. 1. Operation of the disclosed amplifier in other control situations will be readily understood in the light of the foregoing teaching.

The amplifier 130 of FIG. 3 is identical to amplifier 30 of FIG. 1 with the exception of the orientation of airfoil 15, Elements in FIG. 3 identical to those in FIG. 1 have the same last two digits as those of FIG. 1, but are prefaced by the numeral 1. In FIG. 3, the sharp edge 120 of airfoil 115 is also the leading edge of the airfoil as it is positioned adjacent power nozzle 112. The airfoil is symmetrically positioned in interaction chamber 128 so that edge 120 will divide the power fluid. Control port 132 is located on airfoil 115 and is adapted to receive a control pressure. The control port leads to control tube 117 which is positoned to direct control flow towards left output channel 123. Right control port 133 leads to right control tube 116, the latter being similarly positioned with respect to right output channel 122.

When no control signals are applied to

control ports

132, 133, sharp edge 120 of airfoil 155 will evenly divide the flow from power nozzle 112. The flow will attach to the

sides

118 and 119 of the airfoil in a manner wellknown in the art and will issue from center output channel 121. In FIG. 3, the sharp edge 120 splits the power fluid and because of the sharpness of the edge, the power fluid attaches to the sides of the airfoil instead of being deflected as in FIG. 1.

If a control signal is applied to left control port 132, the control flow from tube 117 will proportionately direct the power fluid on the left side of airfoil 115 into left output channel 123, thus directing power fluid to two output channels. If a signal is simultaneously applied to right control port 133, control flow will issue from right control tube 116 and proportionately direct power fluid into right output channel 122.

As the strength of the control signal increases, more power fluid will correspondingly be deflected rendering the output proportional to the control signal.

The flow resulting from a control signal to right control port 133 in the absence of a signal to left control port 132 will be readily understood in the light of the foregoing teaching.

The amplifier of FIG, 4 is identical to the amplifier of FIG. 3 with the addition of splitter 135, which is positioned to touch trailing edge 134 of airfoil 115. The splitter defines the center output channel of FIG. 3 into a right center output channel 137 and a left center output channel 136. The operation of the amplifier of FIG. 4 is similar to the operation of FIG. 3 except that when fluid attaches to the right side 119 of the airfoil 115, it will be directed to right center output channel 137 instead of a center output channel. A similar result will occur for the left side of airfoil 115. The addition of splitter 135 in no way affects the operation of the control tubes directing power flow into the right and left output channels respectively.

We claim as our invention:

1. A fluid amplifier comprising:

(a) an interaction chamber,

(b) a left and right sidewall each bracketing said interaction chamber,

(c) a power nozzle,

(d) a source of power fluid communicating with said interaction chamber by said power nozzle,

(e) plural output channels communicating with said interaction chamber,

(f) an airfoil symmetrically placed in said interaction chamber, and

(g) control means on said flow guiding body to selectively direct said power fluid into said output channels.

2. A device according to claim 1 wherein:

(a) a left divider is adjacent to said left sidewall and defines a left output channel,

(b) a right divider is adjacent to said right sidewall and forms a right output channel,

(c) said dividers forming between themselves a center output channel.

3. A device according to claim 2 wherein said control means includes means to receive a control flow and further means to utilize said control flow to divert said power fluid from at least one output channel to at least one other output channel.

4. A device according to claim 2 wherein, said control means comprises at least one control port adapted to receive a control flow and a control tube communicating with said control port.

5. A device according to claim 4 wherein said control tube is positioned to direct said control flow into said center output channel.

6. A device according to claim 5 wherein said airfoil has a sharp end and a rounded end, said rounded end of said airfoil being adjacent said power nozzle.

7. A device according to claim 6 wherein a third divider is adjacent said sharp end of said airfoil to divide said center output channel into a right center output channel and a left center output channel.

8. A device according to claim 4 wherein said control tube is positioned to direct said control flow into an output channel adjacent one of said sidewalls.

9. A device according to claim 8 wherein said flow guiding body is an airfoil, said airfoil having a sharp end and a rounded end.

10. A device according to claim 9 wherein said sharp end of said airfoil is adjacent said power nozzle.

11. A device according to claim 10 wherein a third divider is adjacent said round end of said airfoil to divide said center output channel into a left center output channel and a right center output channel.

(References on following page) 5 6 References Cited 3,177,888 4/1965 Moore 137-815 3,181,545 5/1965 Murphy 137 s1.s UNITED f PATENTS 3,247,860 4/1966 Zilberfarb 137-815 3,030,979 4/1962 3,276,473 10/1966 Lewis et a1. 137-815 3,039,490 6/1962 Carlson 3,326,227 6/1967 Mitchell 137-81.5 3,171,422 3/1965 Evans 137--s1.s 5

3,172,495 3/1965 Bliss et a1 137-815 XR SAMUEL SCOTT, Primary Examiner,