US2453595A - Apparatus for dispensing liquid fuel - Google Patents

Description

Nov. 9, 1948. H, ROSENTHAL 2,453,595

APPARATUS FOR DISPENSING LIQUID FUEL Filed Aug. 27, 1943 3 Sheets-Sheet l INVENTOR ADOL HVH. POSENTHAL ylaw/ ATTORNEY Nov. 9, 1948. I RQSENTHAL 2,453,595.

APPARATUS FOR DISPENSING LIQUID FUEL Filed Aug. 27, 1943 3 Sheets-Sheet 2 4) @bp'b.

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INVENTOR A001 PI H. A 055 N THAL ATTORNEY 1948- A. H. ROSENTHAL 2,453,595

APPARATUS FOR DISPENSING LIQUID FUEL Filed Aug. 27, 1943 3 Sheets-Sheet 5 D C) c G INVENTOR ADOL HYH. ROSENTHAL waw,

ATTORN EY Patented Nov. 9, 1948 2,453,595 APPARATUS FOR DISPENSING LIQUID FUEL Adolph H. Rosenthai, New York, N. Y., assignor to Scophcny Corporation of America, New York, N. Y., a corporation of Delaware Application August 27, 1943, Serial No. 500,242

Claims.

This invention relates to a method and apparatus for feeding liquid fuel of any kind into combustion air of internal combustion engines.

Intemal-combustion engines operated by volatile or light liquid fuels are ordinarily provided with a carburetor outside of the cylinder into which the liquid fuel is fed, usually by means of an adjustable nozzle. During the suction stroke of the engine operating either on the fouror two-stroke cycle, combustion air is drawn in through the carburetor and passes the nozzle; depending upon the adjustment of thenozzle, the velocity at which the air stream passes the nozzle and the character of the. liquid fuel, particularly its volatility, the fuel will be admixed in measured quantities and more or less evenly distributed and volatilized in the air-stream. Experience shows that particularly in high speed engines sometimes only part of the liquid fuel is volatilized in the carburetor and manifold and the remainder carried along by the air-stream in the form of small droplets into the cylinder wherein they are vaporized during the compression stroke. It then frequently happens that some droplets still remain as such in the compressed air and upon ignition of the thus incomplete mixture are burned relatively slowly; thereby the efficiency of the engine is reduced and socalled detonations or knocking occurs.

Another difliculty attending this method of feeding liquid fuel into the combustion air consists in maintaining the best air-fuel ratio at various speeds and loads of the engine, It theoretically requires current adjustment of the carburetor depending on varying speeds and loads which is impossible in practical operation. Additional compensating nozzles were suggested for this purpose but they complicate the design of the engine. Fuel pumps, the delivery of which is regulated automatically depending on varying speeds of the engine, afford no complete remedy because they do not affect the volume of combustion air passing the carburetor.

Enginesoperating on the Diesel or semi-Diesel principle generally use heavy and non-volatile liquid fuel which is injected into the cylinder either by air injection (using a part of the combustion air compressed outside of the cylinder by a separate compressor), or solid injection (using a fuel pump driven by the engine). With both methods difliculties areencountered in finely and equally dispersing the liquid fuel while being inlected and in distributing it uniformly in the highly compressed and thereby heated air in the cylinder.

2 thermal efficiency of such types of engines largely depends upon the fine and uniform dispersion of the fuel in the compressed combustion air in the cylinder.

High speed engines operating on any ofthe above principles and used particularly in vehicles of any type, require highly purified and active fuel. The available liquid fuels are therefore, and in order to prevent its deterioration or change upon shipping and storing, subjected to complicated and sensitive refining or purifying processes which also serve to break down (crack) undesirable highly polymerized components and to destroy otherwise detrimental components, such as olefines.

It is therefore an object of the invention to secure more complete. volatilization of volatile liquid fuel supplied to the combustion air drawn into internal-combustion engines.

It is another object of the invention to secure an as fine as possible atomization or dispersion of liquid fuel to be admixed to the combustion air while the latter flows to or is in the cylinder.

It is still another object of the'invention to secure a more intimate admixture of the atomized liquid fuel to and uniform distribution in the combustion air, while'the latter flows to or is in the cylinder.

It is a further object of the invention to highly disintegrate or atomize the liquid, volatile or nonvolatile fuel to be admixed with the combustion air flowing to or being in the cylinder and simultaneously to cause uniform distribution of the atomized fuel particles in that air and, if the fuel be volatile, their almost instantaneous volatilization.

It is still another object of the invention to finely disintegrate or atomize liquid fuel containing highly polymerized components and to break down the latter simultaneously, immediately and uniformly admix it in this state to the combustion air flowing to or being in the cylinder, and, if volatile fuel be concerned, to secure its ahnost instantaneous volatilization. a

These and other objects of the invention will be more clearly understood when the specification proceeds with reference to the drawings in which Fig. 1 shows in vertical cross section and rather schematically a constant-level fuel supply and a fuel integrating and dispensing device (carburetor) according to the invention, Fig. 2 rather schematically a cross section through a dispensing and integrating device using a piezoelectric element, and a diagram of an oscillation generator coupled therewith, for an engine of the Otto-typ F18. 3 a vertical cross section through a fragment of a suction pipe of such engine provided with an electromagnetically operated fuel integrator according to the invention, Fig. 4 a vertical cross section through the head and upper portion of a cylinder of a Diesel-type engine, provided with a fuel integrator using a piezoelectric element, Fig. 5 more in detail and in vertical cross section a fragment of a suction pipe of an Otto-type enginewith a dispensing and integrating device on a larger scale, Fig. 6 a vertical cross section of a modification of such device,

Fig. 7 a vertical cross section through a fragment of a suction pipe of an Otto-type engine with a dispensing and integrating device operating on a magneto-striction principle, Fig. 8 a vertical cross section through a cylinder head of a Dieseltype engine provided with a dispersing and dispensing device operating on the magnetostriction principle, Fig. 9 in vertical cross section another modification of a fuel dispensing and integrating device for an Otto-type engine, Fig. 10 a top view, partly in cross section along line lI-lfl in Fig. 9, Fig. 11 a. view with parts in cross section along line |l-ll in Fig. 9; Fig. 12 a vertical cross section through a further modification of a dispensing and dispersing device for an Otto-type engine, Fig. 13 a top view, with parts in cross section along line l3l3 in Fig. 12, and Fig. 14 a cross section along line I4-|4 in Fig. 12.

The principle of the invention may be explained with reference to Fig. 1 and in application to an internal-combustion engine operating on the twoor four-stroke Otto cycle. 10 is a conduit through which combustion air is drawn in the direction of arrows II to a manifold and the inlet side of the cylinder or cylinders (not shown). A metallic cup or pan I2 is connected by pipe or conduit l3 with the interior of vessel H which is filled with volatile, liquid fuel IE to level l6; liquid fuel from a supply (not shown) is fed to vessel ll through conduit l1, either by means of a fuel pump or by suction according to well known methods which do not form the sub- Ject matter of the invention and are therefore not shown in detail. The end of conduit l1 within vessel I4 forms a seat SI for a valve IS the stem of which is hinged to one end of a lever l9 pivotally held by bracket 20. A float 2i is adjustably mounted on the other end of lever l9 and submerges into the liquid fuel I5. The design is such that valve l8 rests on seat 6| and thereby closes conduit I! when the level I6 is so high that the fuel in the communicating pan i 2 maintaining a thin film thereof on the upper surface of a piezo-electric element, such as quartz crystal 22 arranged within cup 12.

It is well known in the art that crystals of certain substances, such as quartz, tourmaline, Rochelle salt, etc., exhibit piezo-electric effects, 1. e. oscillate mechanically under the action of oscillating electrical energy applied to them in spaced planes perpendicular to a polar axis. The polar axes of such crystal being ascertained by methods well known in the art, preferably a plate of rectangular or square cross section is cut from the crystalin such a manner that two parallel surfaces of the plate are perpendicular to the selected polar axis ("Curie cut); if there are two such axes, the one is preferred in the direction of which longitudinal or thickness-oscillations occur upon application of an oscillatory energy of proper frequency. It is also known in the art that the longitudinal resonance frequency of such a crystal piece depends primarily upon its thickness and not upon its width or length; that the resonance curve of its oscillation is extremely sharp: and that it is capable of vehement oscillations in its fundamental resonance frequency as well as in odd integer harmonics thereof.

The energy of the thickness or longitudinal mechanical resonance vibrations of the properly cut piece within the supersonic frequency range, between about 10,000 to about two million periods per second, can be great and requires several hundred to a few thousand volts for its excitation. Electrodes covering relatively small surface areas of the piece suffice for the generation of highly energetic mechanical thickness-vibrations. Although in the following reference will be made only to the preferred thickness-vibrations, it should be understood that the use of transverse mechanical vibrations caused. perpendicularly to the direction of a corresponding polar axis of a piece properly cut from a piezoelectric crystal, is within the scope of the invention.

Fig. 2 shows schematically and partly on an enlarged scale an electric arrangement for exciting mechanical vibrations of a crystal piece 22 cut in the manner described hereinbefore. The cut of the piece is such that its upper and lower plane surfaces are perpendicular to its polar axis in the direction of which thickness oscillations occur upon application of an oscillating electric current of proper voltage and a frequency corresponding to the selected thickness of the piece. Its lower surface is covered entirely or in part by an electrode 23 consisting, e. g. of a spray of aluminum or any other electrically well conductive material, such as copper; the electrode material may also be sputtered upon the surface or part of it, or deposited on it by a well known evaporation process, or cathode sputtering, in vacuum. In similar manner, an electrode 24 is provided on top of piece 22, covering it entirely or e. g. along its edges only. Instead of spraying or sputtering, etc., the electrode upon the upper surface of piece 22, a metal ring or piece may be put onto it in contact therewith, as will be illustrated later on. The upper electrode 24 of any proper shape and material is conductively connected at 25 with terminal pin 26 passing an insulating collar-21 mounted in metal cup I2; the insulating collar can also be omitted. The bottom electrode 23 is connected with the other conductive terminal pin 28 passing the electrically insulating piece 29 liquid-tightly mounted in the bottom of cup l2.

Any type of generator of electric oscillation can be used for exciting the mechanical vibrations of piece 22. In Fig. 2, the diagram of a Hartley circuit is shown. It comprises in its most simple form and essentially a triode 30 with cathode 3|, grid 32 and plate (anode) 33. N is a source of current for heating cathode ll; 25 is a source of plate current; 35 a make and break switch for starting and interrupting the oscillations; 31 a resistance in the heating circuit of the cathode from which, over leak resistance 38, a desired bias of grid 32 can be derived by adjustable tap 39; 40 is a block condenser; 4| is a self-induction coil and 42 an adjustable condenser forming together an oscillation circuit of variable frequency which determines the frequency of the oscillations generated; and 43 is an adjustable tap for connecting a desired point of coil 4! with the positive terminal of source 38. By adjusting condenser 42, the frequency generated is determined; by adjusting tap 39 or 43, the energy of the high frequency oscillations generated and thereby of the mechanical vibrations of piece 22 is determined. Other means and arrangements for generating supersonic or high frequency oscillations of desired frequency and energy can be used instead of the illustrated ones. It will be appreciated that the piezo-electric piece with its electrodes forms a small capacitance in parallel to variable condenser 42 and self-induction coil 4|, which is of negligible influence upon the frequency developed and in any event of constant value for all practical purposes. The frequency of the generator is to be adjusted so that it equals the fundamental resonance frequency of piezo-electric piece 22 or an odd integer harmonic frequency thereof. The energy of the excited mechanical vibrations depends of course upon the electric oscillatory energy applied to piece 22; adjustment of the latter energy is possible within wide range and gradually in the manner described, and/or by adJusting the bias of grid 32 and/or the plate voltage and/or the heating current of cathode 3i, etc.

While the frequencies impressed uponpiece 22 may be within the audible range, the supersonic or high frequency range is preferred not only because its effect for the purposes of the invention is far greater, but also because generation of audible sound should be avoided in the engine.

Float 2| and the mechanism connected therewith are adjusted in such a manner that level it, Fig. 1, and thereby the level of the liquid fuel in cup I2 is above electrode 25 at desired and adjusted height.

Upon closing of switch 36, self-oscillations of the generator set in and excite piece 22 to mechanical oscillations of the same frequency perpendicular to the surfaces on which electrodes 23, 24 are applied, 1. e. to thickness vibrations of an energy defined by that of the electrical oscillations. These vibrations are imparted to the layer of liquid fuel upon the exposed upper surface of piece 22. As a. consequence liquid fuel comprised by the layer is thrown off vehemently and finely dispersed into the combustion air above piece 22. The vibrations of the liquid layer are, however, also imparted to the combustion air in contact therewith, and that air is thrown off simultaneously with the fuel particles or droplets from the exposed surface of the fuel layer, leaving a kind of vacuum above the layer into which instantaneously fresh combustion air is sucked. Thereby an utterly intimate mixture between continuously flowing-in, fresh combustion air and the thrown oif finely divided fuel particles is produced, and the fuel particles of substantially colloidal size are dispersed and intimately and uniformly admixed with the simultaneously thrown off combustion air. As a consequence, the fuel particles volatilize quickly and a complete fuel-air mixture results which now is drawn into the engine during its suction stroke.

The fuel layer on the upper surface of piece 22 grates the dispersed particles with the combus tion air in the manner described. While the volume per time unit of combustion air passing the fuel dispensing device can be regulated by the operator or automatically depending on the load and desired speed of the engine, the amount of fuel dispensed and integrated in the volume of air passing the device depends primarily upon the dispersing and integrating effect of the new device according to the invention which in turn depends upon the vibration energy translated to piece 22. Electric means for'gradually or stepwise increasing or decreasing the energy of the oscillations generated are described above. They can be actuated by the operator or automatically. e. g. depending on speed and/or load, independently from the means regulating the volume of combustion air admitted to the engine, or coupled with them. Thus, for instance, a speedometer or governor may control both the admission of air and the oscillation iergy generated, though each according to individual laws securing greatest efficiency of the engine as well as complete air-fuel mixtures of predetermined varying (with speed and/or load) or constant ratio.

Experiments have shown that by subjecting the layer of liquid heavy fuel to mechanical vibrations of such high frequency and energy, destruction or mec 'zanical cracking of highly polymerized larger molecules of the organic fuel and thereby their depolymerization occurs.

If vibrations of higher frequency are desired, for instance because heavy fuel comprising highly polymerized components is to be disintegrated, correspondingly higher frequencies are to be used, e. g. in the example stated, condenser 42 may be adjusted to a frequency corresponding to an odd integer harmonic of the fundamental resonance frequency of piece 22. If the engine is to be 0D- erated with different kinds of fuels or at greatly varying loads, a set of individual dispensing devices of different resonance frequencies and/or surface developments and/or potential vibration energies may be arranged in the combustion air and one, some or all of the devices switched in and excited to vibration, in order to obtain optimum effects as to a particular fuel used, or to control the amount of fuel admixed to the combustion air.

The larger the vibration energy, the larger is in general the amount of fuel dispensed by piece 22. The constant level supply as exemplified in Fig. l, or a fuel pump, will secure the maintenance of a layer of fuel of sufficient thickness on top of piece 22.

Thus it will be appreciated that with the invention many advantages are obtained. The liquid fuel, whether volatile or not, is disintegrated or atomized into particles or droplets of very fine, almost colloidal size. If the so dispersed fuel is volatile, the extremely fine droplets are volatilised almost immediately when incorporated into the air-stream and before the latter enters the cylinder. The air-fuel mixture is homogeneous for all practical purposes and obtained in a minimum of time and over a minimum distance passed by the air-stream. If the fuel be nonvolatile, the fine droplets are and remain dispersed and evenly distributed in the air-stream and are carried by it into the cylinder. If the fuel contains highly polymerized constituents, they are destroyed or mechanically cracked into particles of lower polymerization which easily and instantaneously burn when ignited. Regulation of the amount of fuel dispersed and incor.

porated in the air-stream is effected primarily in an electrical way, and therefore gradually and within any desired wide range. The air-fuel ratio can be adjusted substantially independent of the speed and load of the engine, can be kept constant or changing, e. g. by automatic, means, according to a predetermined law afdifferent speeds and loads. It is also evident that the fuelair ratio can be varied without deteriorating the effects of the invention as described, and therefore in particular super-charged engines can be supplied without difliculty with a homogeneous air-fuel mixture obtained and regulated according to the invention. If different kinds of fuel are used in the same engine, or if it is operated in regions of different air density (altitude), complete atomization and vaporization can easily be obtained by adjusting the energy of the oscillating electric current exciting piece 22 and thereby adjusting the amplitude of its mechanical vibrations. Due to the fine dispersion and distribution of the liquid fuel in the air-stream, the air-fuel mixture is rendered very stable and no condensations occur in the bends of the manifold. The structure of the new dispersion and dispensing device (carburetor) is relatively simple and a wide range of adjustment secured of the quantity of fuel incorporated and evenly distributed in the air-stream per time unit, independent of the velocity of the latter and the pressure in the fuel.

A source of electric current is needed for all internal combustion engines operating on an Otto-cycle and from such source the energy can be derived to operate the oscillation generator exemplified in Fig. 2; or a generator can be provided which is driven by the engine.

In order to secure a layer of liquid fuel on top of the vibrator when it sways or rocks due to the motion of the vehicle in which the engine ;is installed, porous substances such as of glass wool, porous sintered glass, fine wire meshes, etc., can be arranged on top of piece 22 so that the fuel is temporarily held within the interstices or pores of this material by capillary action or the like, until it is thrown off. Other means to similar effect will be described hereinafter.

The fuel dispensing device according to the invention can be reduced to small size and will actually occupy only a small portion of the cross section of suction pipe IQ (for clarity's sake the dispensing device in the various figures is shown on a larger scale than actually used) a streamlined cover 54, Fig. 1, can be arranged below the bottom of cup I2, in order to guide the combustion air smoothly around it.

While the invention has been exemplified hereinbefore-by the use of a piezo-electric piece,

' other types of vibrators can be used to similar effect.

Thus, for instance, the exposed surface of a member driven electromagnetically at proper frequency and with sufficient energy may be used for disintegrating and dispensing the fuel. Referring to Fig. 3, such member may consist of a membrane 50 of electromagnetic material held on the edge 49 of a metallic cup 45 by means of a ring screwed upon the lateral outside of edge 49. Inside cup 45 a soft iron core 53 and coil 52 are arranged and the latter connected with insulated conductors 47, 48 passing a hollow bracket 45 mounted in the wall of suction pipe III of an engine operating on an Otto-cycle. Liquid fuel is supplied under ressure through conduit l3 and nozzle 55, preferably by means of a fuel pump, and sprayed upon the exposed surface of memher 50. oscillatory electric energy of proper frequency is supplied through conductors 41, 48 from a generator, e. g. of the type as exemplified in Fig. 2, and thereby member 50 electromagnetically excited to vibrations of a frequency and energy sufficient to disintegrate and throw of! the fuel sprayed upon the exposed surface of member 50 in a manner identical in principle withthat explained hereinbefore with reference to piezo-electric piece 22.

It is understood that coil 52 can be mounted on the inside of member 50 and, upon proper excitation by oscillatory electric energy, vibrate relative to core 53 fixedly mounted in cup 45. It is also feasible to excite mechanical vibrations of member 50 in an electrostatic manner well known in the art, and to replace the membrane-like member 50 by a ribbon of electromagnetic material.

It will be appreciated that member 50 can be excited with desired energy as well as at any desired frequency because metallic membranes of this type can be made so as to vibrate within a large range of oscillations.

While it has been assumed above that the airstream ll results from the suction stroke of the engine, it is clear that a stream of compressed air can be charged effectively with liquid fuel in similar manner. Therefore, if the invention is used for charging compressed air with liquid fuel to be fed into an engine operating on a Diesel or semi-Diesel cycle, essentially the same arrangement can be used as exemplified in Figs. 1 to 3. In such case, however, the dispersed fuel will be essentially non-volatile and therefore carried along by the compressed air into the cylinder where the extremely fine fuel particles uniformly distributed in the compressed air are ignited instantaneously and almost ideal combustion iS obtained.

In engines operating on the Diesel or semi- Diesel cycle liquid fuel is also injected into the combustion space of the cylinder wherein combustion air is compressed near the end of the compression stroke and heated above the ignition temperature of ..1e fuel. In order to secure complete and rapid combustion of the injected fuel, its finest and uniform distribution in that heated air is necessary. According to the invention, an electrically excited mechanical vibrator is used for this purpose. Referring to Fig. 4, 56 is a water cooled cylinder in which piston 51 reciprocates; the latter is shown in its innermost position in which the combustion air is compressed within the combustion space 58 of the water cooled cylinder head 59. The latter is provided with a kind of combustion chamber 60 in which an electrically excited, mechanical vibrator 62 of the piezo-electric type, as illustrated in Fig. 6, is mounted. It suffices to say here that its housing element 63 is screwed into a screw-threaded bore 54 of the water jacketed cylinder head 59 and secured in position by a hollow counter-nut 85. oscillatory electric energy is supplied to it through insulated conductor 66 connected with terminal 61 of the vibrator and through the conductive metallic mass of cylinder 56 and cylinder head 59 which in turn is conductively connected with housing 63. To this end, for instance, conductor 88 of the generator shown in Fig. 2 can be connected with conductor 56, Fig. 4, while conductor 69 in Fig. 2 can be grounded so as to close the supply circuit of oscillatory electric energy through the ground connection 10 in Fig. 4. A conduit 12 9* provided with nozzle 13 ends spaced from the inclined surface ll of vibrator 82. Fuel is pressed through conduit "in the direction of arrow I4 in regulable amounts at recurrent moments timed with the operation cycles, when piston 51 approaches its innermost position shown. Timed and regulable feeding devices for this purpose (fuel pumps) are-well known and therefore not shown. The fuel injected through nozzle 13 is thrown or sprayed in the direction of arrow 14 upon the vibrator surface I I, and disintegrated by and thrown off from that vibrating surface into the highly heated combustion air within chamber 88. Only a small part of the spray emerging from nozzle 15 will be ignited in contact with the heated combustion air; the main body of the spray reaches surface 1|. When the fuel is disintegrated and thrown off surface 1|, also combustion air in contact with surface H is thrown off and thereby 'a kind of circulation caused in the combustion air in the direction of arrow 15; thereby the complete and uniform dispersion of the finely disintegrated or atomized heavy fuel in the combustion air is assisted and most rapid combustion accomplished. Heavy and highly polymerized components of the fuel reaching surface H- are "mechanically cracked.

Instead of a mechanical vibrator of the piezoelectric type, also an electromagnetically excited vibrator of the type shown in Fig. 3 can be used, provided that the insulation of the wires of coil 52 and'conductors 41, 48 is heat resistant and comprised, e. g. essentially of asbestos. An electromagnetically excited vibrator of the type illustrated in Fig. 3 can also be used in place of the piezo-electric piece 22 in Figs. 1 and 2, by arranging the exposed surface of member 58 horizontally and supplying fuel into the space above member ill-inside ring 5|.

Another" manner of injecting fuel directly into the combustion space of a Diesel-type engine is illustrated in Fig. 8. The water jacketed cylinder head 59 is provided with a bore l6 through which a tube TI ending in nozzle 18 projects. Tube ii is mounted outside the cylinder head in a sleeve 19 and connected therein with feeding conduit l3. Tube 88 is seated at one end on shoulder N2 of sleeve 19 and at its other end in recess 8| of portion 82 of the cylinder head. A cylindrical housing 83 with flange 84 is seated on shoulder 84 of portion 82 and preferably bolted thereto (not shown). A nut 81 is screwed into the outer contracted end 86 of housing 83 and presses through sleeve 19 the tube 88 into recess 8|. Thus escape from the combustion space 58 of air and combustion products which enter the narrow space between tubes I1 and 88, is prevented.

Two coils 88, 89 are slipped over and mounted on the outside of tube 88 spaced from one another. Oscillatory electric energy is supplied to them in parallel through insulated conductor 98 and individually through conductors 9|, 92. These three conductors are conveniently combined in a cable 93 passing a hole in housing 83. Since oscillatory electric energy is to be supplied to coils 88, 89, they may be used as self-inductions of the electric oscillation generator and replace the portions of coil 4|, Fig. 2, on both sides of tap 43. In this exempliflcation it is assumed that tap 43 is in a position in which it divides coil 4| intohalves, and coil 88 corresponds for instance to the lower and coil 89 to the upper half of coil 4|. Hence conductor 98 corresponds to wire 95 in Fig. 2 and leads to switch 88, while conduc- .tors 9|, 92 form continuations, respectively, of wires 88, 69 in Fig. 2. It is understood, however, that a complete generator including an inductance 4| can be connected with coils 88, 89, and in such case conductors 9|, 92 can be combined into a single conductor and form a continuation, e. g.

' of wire 68 in Fig. 2, while conductor 98 forms a continuation of wire 69.

Tube 11 consists of ferro-magneti-c material capable of exhibiting a so-called magnetostriction effect, such as nickel or alloys known by the trade names Invar and Monel metal." Tube 88 consists, however, of a non-magnetic material, such as bron'ze, brass, etc.

As is known in the art, a magnetostriction effect can be caused by passing recurrently at certain frequency a magnetic flux longitudinally through an elongated body of ferro-magnetic material which is freely projecting from its mounting. Each magnetic excitation causes a dilation and contraction or mechanical vibration, of the freely projecting portion of the body in its longitudinal direction, the amplitude of which is greatest at the free end of the body. The frequency at which this phenomenon occurs strongest equals the resonance frequency of the body and in the case described its mounting forms a node and its free end is spaced therefrom for A wave length. Therefore, the freely projecting tube 11 measured from its mounting in sleeve 19, corresponds to A of its wave length at resonance frequency. A rather high resonance frequency within supersonic range is preferred. The energetic longitudinal oscillations of tube "I1, comprises periodic contractions and dilations in the direction of its axis the amplitude of which is greatest at nozzle I8, are permitted by its spaced arrangement within tube 88 and bore 16. The magnetic flux recurrently produced by coils 88, 89 is closed through ferromagnetic tube 11 and not by-passed through tube 88 since the latter consists of non-magnetic material. Coils 88, 89 determine the frequency of the oscillatory energy and produce the magnetic flux; they are unaffected by the longitudinal mechanical vibrations of tube 'II from which they are spaced by tube 88.

The fuel pressed into and passing tube in the direction of arrow 94, will be subjected to the action of the preferably supersonic longitudinal mechanical vibrations of tube 'I'I the amplitude of which increases toward nozzle 18. The fuel in contact with the inner surface of tube I1 is taken along and accelerated upon longitudinal dilation of tube 11 and is immediately thereafter retracted upon longitudinal contraction of the tube. The fuel column proceeding through tube I1 is subjected to such action at increasing extent toward nozzle 18 where the amplitude of the vibrations is greatest and results in tearing the'column to finest pieces or droplets which emerge and are vehemently ejected from nozzle 18. Projections arranged, if desired, within nozzle 18 were found to increase this disrupting effect.

By properly dimensioning the length, thickness and diameter of freely projecting tube 'I'I including nozzle 18 and tuning to its resonance frequency, the frequency of the oscillatory electric energy supplied to coils 88, 89 (which translate the electric energy into periodically recurring magnetic fluxes) and by adjusting the magnitude of that electric energy, the intensity of the longitudinal mechanical vibrations of pipe 11 and thereby the degree of disintegration of the fuel passing it, can be conveniently regulated in 11 a purely electrical manner, gradually or stepwise. The amount of fuel passing tube 11 is measured and timed independently. It will be convenient to regulate the magnitude of the electric oscillatory energy supplied depending on the amount of fuel passed through pipe 11, so as to increase this energy with increasing amount of fuel to be disintegrated, and vice versa. Automatic means to this effect are'essentially the same as previously described for regulating the excitation of piezo-electric piece 22.

Magnetostriction effects can also be used for dispensing and dispersing fuelinto combustion air of engines of the Otto-type. To this end, Fig. 7, a solid or hollow rod 96 of ferromagnetic material is mounted in a bracket 91 provided with spokes 98 ending in ring 99 mounted between flanges I00, IOI of the portions I02, I03 of the air intake pipe of an Otto-type engine.

Rod-96 is preferably enlarged on its top end to form a head or plate I04. Rod 96 is arranged within and slightly spaced from a cylindrical housing I05 of non-magnetic material which is mounted at its bottom, e. g. screwed into bracket 91 and enlarged at its top to form a cup I06 provided with an inlet I'I connected with a pipe I I0 passing wall I02 to the outside. Another housing element I09 of non-magnetic material is connected, e. g. by welding at its top with cup I06 and its bottom mounted (screwed) upon bracket 91. Coils 08, 89 are spacedly arranged between the housings I05, I09 and connected with conductors 90, SI, 92 in a manner and for a purpose the same as described hereinbefore with reference to Fig. 8. The freely projecting rod 96, with head I04, of ferromagnetic material is capable of magnetostriction resonance vibrations in the direction of its vertical axis, and is to be dimensioned so that the frequency of those vibrations is preferably supersonic. The magnetostriction vibrations are excited by coils 88, 89 upon feeding oscillatory electric energy of that resonance frequency thereto, in the manner as described hereinbefore with reference to Fig. 8.

Liquid, preferably light and volatile fuel is fed into pipe 0 in the direction of arrow II I and enters the space between the inside of cup I06 and head I04; it may also flow into the space between rod 96 and housing I which is liquid-tightly closed at its lower end, without interfering with the longitudinal or axial mechanical vibrations of rod 96. The fuel is fed within cup I06 by means of a constant level supply as illustrated in Fig, 1, or by a fuel pump, to a predetermined level above the upper exposed surface of head I04. The longitudinal vibrations of head I04 will then disintegrate or atomize the layer of fuel and throw it off essentially perpendicularly to the upper surface of head I04 in the same way as described with reference to plezo-electric piece 22, Figs. 1, 2

The uppermost portion of rod 96 and/or head I04 may be made of a non-magnetic material, e. g. aluminum.

In the following, various features of piezo-electric dispensing and integrating devices embodying the invention are described.

Referring to Fig. 5, a properl cut piezo-electric element 22, such as a cylindrical plate, is provided with a ring-shaped electrode 24 on top and another electrode H3 in the shape of a circular metal plate, e. g. of aluminum or steel, on the bottom. It flts rather snugly inside a cupshaped insulator II4 of porcelain, or like insulating material, provided with a hollow cylindrical extension II5 through which the terminal pin is passed. Onto the upper end of pin 20 a rather hard spring H6 is riveted and supports and engages the bottom electrode H3. A metal shell II! is slipped over insulator H4 and engages electrode 24 with its upper. inwardly extending flange II6. which is provided with one or more notches H9 the bottom of which is preferably level with the edge of insulator III. shell I" is screw-threaded over a part of its outside periphery and screwed into a metal cup I20 provided with a hole I2I in its bottom through which extension II5 passes. A washer I22 of electrically insulating material covers that hole and is held in place by nut I23 screwed or otherwise fastened upon pin 28. A ring 89 between flanges I00, IOI of pipe portions I02 I03 forming an intake conduit of an Otto-type engine, supports by means of spokes I24, I25 a cylindrical member I26, the lower inside portion of which is screwthreaded and the upper end of which continues into a curved rim I21. Spoke I25 is hollow and forms a. duct I28 into the outer end of which the end of conduit I3, Fig. l, is screwed.

Cup I20, shell III, insulator H4 and piezoelectric element 22 obviously form a unit which can be screwed from below into and removed from member I26. A hand-hole (not shown) may be provided for this purpose in pipe I03.

It will be appreciated that this vibrator unlt forms a rugged entity which can easily be replaced by one of the same or different vibration characteristics; the latter may be chosen, for instance, if a different kind of fuel is to be used or the altitude is changed in which the engine is to operate. The differences between such units consist primarily in different thicknesses and possibly different exposed surface areas of piece 22.

When this vibrator unit is mounted in member I26, fuel admitted through conduit I3 and duct I28 will fill the space between rim I21 and flange II8 as well as pass notch or notches II! and discharge upon the exposed upper surface of element 22. Upon application of proper oscillatory electric energy through conductor 60. terminal 28 and spring I I6 to the bottom electrode II3. on one hand and through ground 10, pipe I03. spokes I24. I25, member I26, cup I20. shell II! and flange III to electrode 26 on the other hand, element 22 will be excited to resonant thickness vibrations and disintegrate and throw off the fuel supplied upon its upper exposed surface into the combustion air flowing around the vibrator unit in the direction of arrows II. The thickness vibrations of great, adjustable energy are translated to the fuel flooding the exposed surface of the vibrator and imparted to the surface of the fuel layer as well as the combustion air in contact with the latter. Thus the effects previously described with reference to Figs. 1 and 2 are realized and the disintegrated or atomized fuel is thrown off essentially perpendicular to the vibrating exposed surface of element 22 and dispensed into and integrated with the combustion air to form a kind of colloidal aerosol with it, which is drawn into the engine cylinder.

Although the thickness vibrations particularly of supersonic frequency are of great acceleration, their amplitudes are extremely small so that spring II6 and the supporting unit in contact with the vibrator element 22 will not be excited to vibration.

If element 22 does not fit snugly into insulator H4, the fuel-enters the space between them; this does not interfere with the operation of the device because the fuel is an insulating liquid.

Fig. 6 illustrates a vibrator unit which can be mounted in member I20, Fig. 5, or in bore 84 of cylinder head 59 in Fig. 4. In the latter case cup I20 is preferably shaped in the manner shown for cup 63 in Fig. 4, and some notches are to be provided in flange II8 to facilitate screwing in end out of the unit.

The unit shown in Figs. 9. 10 and 11 differs from the one illustrated in Fig. as to the structure of the vibrator element. It consists of two plates I29, I30 of metal, such as steel, each of which is provided with elongated holes or ducts I M I32, respectively. Between metal plates I29, I30, square shaped plates I33 of piezo-electric material, such as quartz, are cemented. Thereby a unitary vibrator element is obtained consisting of steel plates I29, I30 and mosaic-like arranged quartz pieces I33 in between. The metal (steel) plates conveniently serve as electrodes. The speed of sound propagation through steel and quartz being approximately equal, this unitary vibrator element reacts as a vibrating entity upon oscillatory electric energy applied thereto by thickness vibrations the resonance frequency of which is determined by the total thickness of the element, viz. of the two steel plates plus the quartz pieces between them. In other words, in spite of the combination with the quartz pieces of steel plates, the unitary element will vibrate as if it consisted entirely of quartz. If the total thickness thereof be 5 mm. or mm., a frequency respectively of about 600,000 or 300,000 cycles per second will excite the unitary element to resonance vibrations.

The engaging parts of member I26, cup I20, and shell II1 are cylindrical and so is the outer vertical circumference of insulator H4. The inner vertical surface of insulator II4 is, however,

essentially square shaped and spaced from the substantially square shaped vibrator unit I29, I30, I33. Vertical ducts I34 in any desired and proper number are provided in the insulator which communicate with the space below the unitary vibrator element and through openings I35 in flange I I8 with the space between the latter and rim I21. Fuel supplied through duct I28 will therefore flow through the space between rim I21 and flange II8, openings I35 and ducts I34 into the space within the insulator II4 surrounding the lateral and bottom surfaces of the unitary vibrator element, and rise through ducts I32 in plate I30 and the spaces between the quartz pieces I33 and ducts I3I in plate I29 to and flood the upper exposed surface of the unitary vibrator element wherefrom it is dispensed and distributed into the combustion air in the manner described hereinbefore.

Particular advantages of this unitary vibrator element consist in that the fuel passing the ducts and spaces of the vibrator element is somewhat disrupted by its vibrations and therefore mo e easily and completely atomized on its exposed surfaces. Moreover the fuel supplied by a constantlevel device as shown in Fig. 1 or under pressure by a fuel pump, e. g. in timed relation to the operation cycle of the engine, is conveyed through confined space to the exposed surface of the vibrator element; therefore if the vibrator element sways or rocks, the supply of fuel to its dispensing and disintegrating surface is secured.

The embodiment of the invention illustrated in Figs. 12 to 14 differs from that Just described only 14 as to the structure of the vibrator element proper and the supply of fuel thereto. Y

The vibrator element comprises a piezo-electric piece 22 cut in the manner previously described and provided with an electrode, such as a plate I3 on the bottom and another electrode I34, preferably of steel, on top. The latter is traversed by a plurality of ducts I31 in one direction and ducts I38 in a direction preferably perpendicular thereto. The ducts-may be of circular cross section and therefore easily bored into a solid steel plate.

At the points where ducts I31, I38 cross, ducts I39 are bored and connect the intercommunicating network of ducts I31, I38 with the upper exposed surface of the vibrator unit composed of piece 22 and electrodes II3, I 36. The outer ends of ducts I31, I39 communicate with headers or channels I40 in front of which a convenient number of vertical notches MI in insulator II4 open. The space between flange H8 and rim I21 connects through openings I35 with notches I.

If the electrodes H3 and I36 are, e. g. of steel, the resonance frequency of the vibrator element is again determined by the total thickness of electrodes II3, I36 and quartz piece 22 cemented between them.

Fuel is supplied to the vibrator element through a closed system of spaces, channels and conduits, to wit: space between rim I21 and flange II8 (which practically liquid-tightly close upon electrode I36 in the same way as they close upon electrode I29 in Fig. 9), openings I35, notches I4I, headers I40 to the network of ducts I31, I38, from which it rises or is pressed through bores I39 to the exposed dispensing and disintegrating surface of electrode I36. This unit as well as the one shown in Fig. 9 can be easily replaced by a similar or different one, of the same or different resonance frequency, for the purposes stated hereinbefore.

It is also evident that with the embodiments of the invention illustrated in Figs. 9 to 11 and 12 to 14, uniform distribution of the fuel to the dispensing surface of the vibrator element is secured, and consequently vibrator units of large active surface areas can be made accordingly.

It is to be understood that my invention is not limited to any specific example referred to herein, but is to be derived in its broadest aspects from the appended claims.

What I claim is:

1. For use in intemal-combustion engines, a dispensing device for liquid fuel comprising a vibratory element having an exposed surface and capable of supersonic mechanical vibrations including an effective component essentially per pendicular to said surface, said vibratory element including a piece cut out of piezo-electric crystalline material the confines of which comprise two spaced planes essentially perpendicular to a polar axis and parallel to said surface; an electrode associated with each of said planes; 8. cup-shaped electrical insulator holding said vibrator element, said surface within the opening of said insulating cup; a metal shell holding said insulator and a terminal passing said insulator for translating oscillatory electrical energy to one of said electrodes; another terminal connected with the other electrode and exemplified by a conductive connection between it and said shell; said vibratory element, insulator and shell forming a unit removably mounted in a support; and said support provided with means exemplifled by a duct for feeding liquid fuel upon said surface.

2. For use in internal-combustion engines, a dispensing device for. liquid fuel comprising a vibratory element having an exposed surface and capable of supersonic mechanical vibrations including an effective component essentially perpendicular to said surface, said vibrator element including a piece cut out of piezo-electric crystalline material the confines of which comprise two spaced planes parallel to that surface and essentially perpendicular to the polar axis in the direction of which thickness vibrations can occur; an electrode associated with each of said planes, one of said electrodes forming said exposed surface and traversed by ducts communicating with said surface; a cup-shaped electrical insulator receiving said element, said surface within the opening of said cup; at least one metallic shell enclosing said insulating cup and provided with a rim liquid-tightly engaging the edge of said surface and electrode; communicating channels within said shell and insulator to be passed by liquid fuel to be discharged into said ducts within said electrode; and a terminal passed through said insulator and connected with the other electrode.

3. For use in internal-combustion engines, a dispensing device for liquid fuel comprising a vibratory element having an exposed surface and capable of supersonic mechanical vibrations including an effective component essentially perpendicular to said surface, said vibrator element including two electrode plates of metal exemplifled by steel, one of said electrodes forming said surface, and a plurality of pieces of equal thickness cemented between said electrodes, said pieces cut out of piezo-electric crystalline material the confines of which comprise two planes parallel to said surface and essentially perpendicular to the polar axis in the direction of which thickness vibrations occur, the spacing of said planes equalling said thickness; said pieces spaced from one another leaving ducts between them and said electrodes passed by ducts in alignment with those between said pieces; a cupshaped electrical insulator receiving said vibrator element, the bottom of said cup spaced from the adjacent electrode plate; at least one metal a rim engaging liquid-tightly said surface and electrode; a terminal passing-the bottom of said insulator and springy means for connecting said terminal with the adjacent electrode; and communicating ducts within said shell and insulator discharging into the space between the bottom of the latter and the adjacent electrode, so that liquid fuel fed into said ducts from the outside enters said space and through the aligned ducts in said electrode and between said pieces reaches said surface. I

4. A dispensing device for liquid fuel, including an element having a vibratory surface and internal fuel conducting channels leading to spaced openings distributed over said surface, and means for vibrating said element in a direction substantially perpendicular to its vibratory surface and at supersonic frequency.

5. A dispensing device for liquid fuel, including an element having a vibratory surface and internal fuel conducting channels leading to spaced openings distributed over said surface, means for supplying liquid fuel to said surface through said channels, and means for vibrating said element in a direction substantially perpendicular to its vibratory surface and at supersonic frequency.

ADOLPH H. ROSENTHAL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS FOREIGN PATENTS Country Date England July 4, 1939 Number Number

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