US 3204652 A
Description (OCR text may contain errors)
Sept. 7, 1965 P. BAUER 3,204,652
FLUID SIGNAL GENERATOR Filed Dec. 28, 1961 FIG. I
24 12} j f fi 14 1 my I 1 Q 12- 2s 18 14-- FIG. 10.
l/VI/E/VTUR PETER BAUER ATTORNEY United States Patent 3,204,652 FLUID SIGNAL GENERATOR Peter Bauer, 'Ambler, Pa., assignor to Sperry Rand Corporation, New York, N.Y., a corporation of Delaware Filed Dec. 28, 1961, Ser. No. 162,776 9 Claims. (Cl. 137-815) It is a further object of the invention to provide an improved fluid pulse generator adapted to produce fluid pulses of variable time duration.
It is a still further object of the invention to produce an improved fluid pulse generator adapted to produce fluid pulses at a variable repetition rate.
According to the invention, means are provided to direct a fluid power stream representing an output pulse to pass on opening in an enclosure to create a partial vacuum within the enclosure. When the vacuum within the enclosure reaches a certain level, the resulting pressure drop causes the power stream to deflect into said enclosure. After the pressure in the enclosure rises to a certain level, the power stream is switched back and resumes its original path of flow.
Further objects of the invention will become apparent upon reading the following specification, together with the accompanying drawing, in which:
FIG. 1 illustrates a plan view, partly broken away, of a device according to the invention.
FIG. 1a illustrates an end view of the device shown in FIG. 1, with means for applying power fluid to the device.
FIG. 2 illustrates diagrammatically another embodiment of the device of FIG. 1.
FIG. 3 illustrates diagrammatically still another embodiment of the device of FIG. 1.
Referring particularly to FIGS. 1 and 1a, a fluid operated device 10 according to the invention is formed by three laminae 12, 14 and 16. Lamina 14 is positioned between laminae 12 and 16, and is tightly sealed between them by suitable means, such as screws or cement (not illustrated). The laminae 12, 14 and 16 may be of any metallic, plastic or other suitable material. For purposes of illustration, laminae 12, 14 and 16 are shown as being of a clear plastic material.
The lamina 14 has a cut-out section, obtained for example, by means of a cutting or stamping operation. The entire cut-out section is designated as a configuration 18. The cut-out section or configuration 18 includes a fluid supply inlet 20, a fluid outlet 22 and a control chamber 24. The fluid supply inlet 20 forms a constricted supply orifice 26, communicating with the outlet 22 and the control chamber 24. The term orifice as used herein includes an orifice, having parallel, converging or diverging walls or any conventional shape. The supply inlet 20 communicates with a bore 28 in lamina 16. The output end of fluid outlet 22 may communicate with various control or utilization devices (not shown) to perform desired Work functions.
Bore 28 may be internally threaded to receive a tube 30 which may be externally threaded. The end of tube 30, extending from lamina 16 is connected with a source 32 of fluid under pressure. The fluid under pressure may be a gas or air, or water or other liquid. Fluid flow regulating devices, such as a valve 34, may be used in conjunction with the fluid source 32, so as to supply a constant flow of fluidat a desired pressure. Such fluid regulating devices are of conventional construction.
The control chamber 24 contains a piston 36 of planar form. The piston is provided with rod 38 by means of which the piston may be moved to different positions within the chamber thereby determining its momentary volume.
Fluid flowing from source 32 and entering the device through supply inlet 20 is, for the purpose of explanation,
assumed to be at a certain pressure above atmospheric pressure. As the stream of fluid is reduced in cross-sectional area in the orfice 26, its velocity increases. The fluid stream of reducedcross-sectional area, indicated by arrow 40, is called the power stream of the device. The design of the device, i.e. the position of the outlet 22 with respect to the control chamber 24, is such that, if no internal or external forces are active on the power stream, it will travel longitudinally from the orifice 26 into the outlet 22 and exit, undisturbed in its motion, via this outlet.
However, since the power stream passes the region 42, where the outlet 22. and the control chamber 24 communicate, the control chamber 24 will be partly evacuated. The pumping action taking place in the region 42 is generally called ejection pumping or jet pumping. As a result of the pumping action a presmre difference arises between the side of the power stream facing the control chamber and the opposite side of the power stream. If this pressure difference is of suflicient magnitude, the power stream will be directed, in whole or in part, into the control chamber 24. This causes the pressure in the control chamber to rise almost instantaneously. When the pressure in the chamber 24 reaches a level which exceeds the pressure produced by the power stream, the power stream will be forced to leave the control chamber 24 and return to its original exit path through outlet 22.
The power stream may be considered as representing a fluid outputpulse. The duration or width of this pulse is equal to the time duration of undisturbed fluid flow, i.e. the time during which the power stream is being directed to the outlet 22. The pulse ends when the power stream is interrupted, i.e. when the power stream is deflected into the control chamber.
From the above description it will be clear that the power stream continues along its linear exit path, as long as the vacuum produced within the control chamber 24 is insuflicient to cause the power stream to switch, i.e. to cause it to deflect into the control chamber. It is seen that the smaller the volume of the chamber 24, the sooner the vacuum level at which switching occurs will be reached. In other words, the smaller the volume of the control chamber, the shorter will be the length of 3 the output pulses. correspondingly, the shorter the length of the pulses, the higher will be the frequency of the generated pulses. Reversely, the larger the volume of the control chamber 24, the lower will be the frequency of the generated output pulses.
The volume of the control chamber 24 is determined by the position of the piston 35 within the chamber. The deeper the piston is positioned within the chamber, the smaller will be the volume of the chamber, and a smaller chamber results in higher frequency of the pulses gen erated. It will be appreciated that in this manner a gradual change of frequency may be elfected over a wide range by the movement of the piston.
The frequency control of the output pulses by means of control chamber 24, need not necessarily be by controlling the volume of the chamber. An alternative embodiment may involve an equally effective control by varying the pressure within the chamber 24 while the volume of the chamber is maintained constant. Such a pressure control may be realized, for example, by means of a heater filament. Such a heater filament may be located within the control chamber and supplied with a current to produce heat. Heat developed by the filament will increase the temperature and pressure within the chamber 24. The change in pressure affecting the power stream will cause it to leave the chamber in the manner described. The amount of heat developed by the filament will determine the time required to build up the pressure Within the chamber to the level where switching of the power stream occurs.
Referring now specifically to FIG. 2, there is illustrated diagrammatically a modification of the device illustrated in FIGS. 1 and 1a. Like parts are indicated with the same reference numerals. The devices of FIGS. 1 and 2 are identical, except that the device of FIG. 2 has an opening 44 adjacent the control region 42. The purpose of opening 44 is to provide an auxiliary pressure on one side of the power stream 42 to aid in the deflection of the power stream into the control chamber 24. Thus, the opening 44 may be employed in various ways to in fluence or control the frequency of the output pulse. The opening 44 may communicate with the atmosphere or with another suitable source of pressure dependent upon the particular design of the system and the results desired.
Referring specifically to FIG. 3, there is illustrated another embodiment of the present invention. Again, the parts are indicated with the same reference numerals when such parts are similar to the ones illustrated in FIGURE 1. The device of FIG. 3 includes a loop 46 branching off from outlet 22 at 48. The loop 46 establishes fluid communication between adown stream portion of the outlet 22 and the control region 42. In this embodiment, a portion of the fluid output from the outlet 22 is returned to the control region 42 through the loop 46. This arrangement makes it possible to provide auxiliary momentum for the switching action of the power stream 40 into the chamber 24.
It will be understood that modifications and variations may be effected without departing from the scope of the present invention. For example, it will be understood that, although the devices illustrated and described are basically of planar construction, a device according to the invention may have a third dimension of substantial magnitude. Specifically, the control chamber need not be planar, but may be cylindrical and be provided with a piston of conventional cylindrical form. Also, the number of power stream inlets, control chambers and power stream outlets may be varied as a specific application of the device may require.
What I claim is:
1. A fluid device for producing output fluid pulse signals comprising a member having an outlet, a source of power fluid, means for directing said power fluid to said outlet along a normal path, a control chamber having a closed end, said control chamber having an open end, disposed adjacent said normal path of flow of said power fluid and in communication therewith, said chamber being angularly disposed with respect to said outlet so that said flow of power fluid in said outlet creates a partial vacuum in said control chamber to cause all of said power fluid to be deflected from its normal path into said chamber for an interval of time sufiicient to build up a pressure in said control chamber to overcome said partial vacuum, and the angular disposition of said chamber with respect to said outlet being such that said flow of power fluid is deflected back to its normal path to said outlet when said partial vacuum in said chamber is overcome by said pressure.
2. A fluid device as set forth in claim 1 wherein means are provided to vary the volume of said chamber whereby pulse signals of a variable frequency may be produced at said outlet.
3. A fluid device comprising a member adapted to permit a fluid to pass therethrough, means for applying power fluid to said member, an outlet from said member normally receiving said fluid, a fluid receiver being closed at one end, said fluid receiver having an open end adapted to communicate with said member so that fluid normally flows past said open end, said fluid receiver having a vacuum created therein in response to the flow of said fluid past said open end to cause said fluid to switch into said fluid receiver, said fluid receiver being responsive to receipt of said fluid to increase fluid pressure theren whereby after a predetermined time said fluid is switched back to said outlet.
4. The invention as set forth in claim 3, wherein said means includes a piston adapted to be displaced within said receiver.
5. A fluid device comprising an inlet for providing power fluid, a first outlet in substantial alignment with said inlet, a second outlet angularly disposed with respect to said first outlet and in communication with said power fluid, and said second outlet having a closed end to form an enclosed chamber to cause a partial vacuum to be created therein to cause said power fluid when said power fluid is directed out said first outlet to thereby switch from said first outlet to said second'outlet and to return to said first outlet when said partial vacuum is overcome by said power fluid a predetermined time after said power fluid has been in said second outlet.
6. A fluid device comprising a member adapted to permit a fluid to pass therethrough, means for applying power fluid to said member, an outlet from said mem ber disposed to receive said power fluid, a control chamber constructed to communicate with said member and being responsive to fluid flow out said outlet to switch all of said fluid into said control chamber, said control chamber being responsive to said fluid switched into it to switch said fluid back to said outlet after a predetermined time.
7. The invention as set forth in claim 6 and means associated with said chamber adapted to vary the volume thereof.
8. The invention as set forth in claim 6, and means associated with said chamber to vary the pressure therein.
9. A fluid device comprising a member adapted to permit a fluid to pass therethrough, means for applying power fluid to said member, an outlet from said member normally receiving said power fluid, an enclosed pressure responsive chamber angularly disposed with respect to said member and communicating with said member at a point where said fluid passes through said member into said outlet such that a vacuum is created in said chamber when said fluid flows through said outlet whereby said fluid is periodically switched into said chamber when said vacuum reaches a predetermined value and back into said outlet when said vacuum is overcome when said fluid has been flowing into said chamber for a pre- 3,053,276 9/62 Woodward 137-597 determined time. 3,072,147 1/63 Allen et a1 137-815 References Cited by the Examiner FOREIGN PATENTS UNITED STATES PATENTS 5 1278782 11/61 France 3,001,539 9/61 Hurvitz 137-8 M. CARY NELSON, Primary Examiner.
3,016,066 1/62 Warren 137-62414 3,024,805 3/62 Horton 137 81.5 ARNOLD GREGG, LAVERNE D. GEIGER,
3,030,979 4/62 Reilly 137624.14 1O Exammers'