US 3766399 A
A generator in which the inductor is operatively connected to spring structure to be periodically oscillated relative to an induced current coil, at frequencies of mechanical resonance and responsive to irregular power strokes of an engine piston.
Description (OCR text may contain errors)
United States Patent [1 Demetrescu  COMBUSTION ENGINE DRIVEN GENERATOR INCLUDING SPRING STRUCTURE FOR OSCILLATING THE INDUCTOR AT THE MECHANICAL RESONANT FREQUENCY BETWEEN POWER STROKES  Inventor: De r n efre scu, 17761Pa1'ment0 Way, Irvine, Calif. 92664  Appl. No.: 298,824
 US. Cl 290/40, 290/1, 123/46,
 Int. Cl. H02p 9/04  Field of Search"; 123/46, 46 F; 185/9;
[451 Get. 16, 1973  References Cited UNITED STATES PATENTS 3,247,406 4/1966 Toesca 290/1 2,083,680 6/1937 Anderson et a1. 123/46 3,398,302 8/1968 Harnau et a] 310/1 S 3,675,031 7/1972 Lavigne 290/1 Primary Examiner-G. R. Simmons Attorney.Charles E. Wills [5 7] ABSTRACT A generator in which the inductor is operatively connected to spring structure to be periodically oscillated relative to an induced current coil, at frequencies of mechanical resonance and responsive to irregular power strokes of an engine piston.
43 Claims, 10 Drawing Figures 40 37 FUEL 64 l 3 A A COMBUSTION ENGINE DRIVEN GENERATOR INCLUDING SPRING STRUCTURE FOR OSCILLATING THE INDUCTOR AT THE MECHANICAL RESONANT FREQUENCY BETWEEN POWER STROKES REFERENCE TO DISCLOSURE DOCUMENT This application incorporates subject matter of Disclosure Document No. 009927, filed Apr. 5, 1972.
BACKGROUND OF THE INVENTION This invention has to do with generation of electricity and for that purpose provides a novel generator of improved design. More particularly, the invention has to do with a radical breakthrough in electrical power generation technology which enables portable, almost pollution-free power generation using conventional fuels and presently widely available and low cost materials of construction.
The invention will be described in embodiments of particular utility in automobile propulsion, but the device and method are plainly applicable to all manner of applications with or without modification, as the case may be, including all those uses now known for electric motors which may be conveniently operated by power provided by the present generator invention and many of those uses thought to be beyond the electric motor as now known for reasons of power, cost or weight.
The automobile has of late been the center of much attention, being attacked as the bete noire of a clean environment and defended as the sine qua non of modern civilization. Unprecendented governmental interest and regulation has produced a storm of engineering effort at the best financed and most capable centers of scientific talent in this country and elsewhere throughout the world. These efforts for the most part have been constrained by traditional thought channels, because of the assumed impossibility of harnessing conventional fuels to unconventional engines.
The conflict between proponents of automobiles and opponents isa contest of economic dimensions. Unusual fuels or battery powered cars would obsolete service stations as they are presently known creating economic chaos in one of the countrys-most basic industries. Turbine powered automobiles pose safety problems of untold difficulty'since no product of like danger potential has ever been mass marketed. Rapid transit can supplement, but .never supplant the private automobile, and even then, only in the most densely populated areas. Indeed, the wideavailability of the automobile has made it possible to have suburbs as we now know them, and suburbs are where people want to live;
The attempted refinement of the present internal combustion engine, or its Wankel counterpart, through extremes of fineness in tuning and tolerances, through tailoring of fuels and through ever more drasticand expensive post combustion treatment ofexhaustgases does not addressthe fundamental problem, but merely applies patches to a basically false premise.
No matter how sophisticated (and costly) the engine refinement, the fuel composition and the after burner technology, the inescapable fact is that an automobile must go fast or slow, it must stop, start and idle, it must accelerate and decelera te; and heretofore these operating requirements have been the shoals upon which improvements in pollution performance have foundered. The presently known internal combustion engines, re-
ciprocatory or rotary cannot be optimized for fast and slow or accelerating and decelerating operation but compromises must be struck between these operating modes, and thus pollution generating nonoptimum perfonnance tolerated a good portion of the time.
My invention takes a different approach. I provide an apparatus which, while using conventional fuel, operates at optimum conditions all the time, or it does not operate at all. The conflicting requirements of more or less power, faster or slower, in operation of the device, e. g., a car powered by my apparatus, are treated in such manner, hereinafter explained, that optimum operation from a pollution standpoint continues regardless of the ebb and flow of power demand.
Moreover, the efficiency is nearly theoretical, fuel consumption is reduced overall, fewer parts are required, and those that are needed are readily available, and in the automobile application, costly gear train parts and their inherent problems are obviated.
Accordingly, as will become apparent hereinafter, the environmental, economic and technological forces heretofore acting in opposition in the development of low cost, safe prime movers have been harmonized through the present invention, in that gasoline distribution is unaffected, present auto design parameters are retained, the auto after-market continues, the atmosphere is not subjected to untold tons of pollutants, and
withal no economically unrealisitc innovation is required.
SUMMARY OF THE INVENTION put is fixed, at a harmonic of the oscillation frequency,
e.g., at 60 Hertz. As is known, the energy required to maintain resonant oscillation is a small fraction of the energy required to oscillate the same mass at other than resonantfrequencies, nonetheless, the energy derived from each oscillation, as voltage and current, isthe same since the induction coil does not know the energy required to move the inductor.
Moreover, because the inductor resonates, the energy pulsesare not only small but may be fixed in total energy and varied in their rate of incidence. Thus, for example, an internal combustion engine may be used to displace a piston carrying the inductor, the cylinder receiving metered and constant or fixed quantities of combustible fuel-air mixture to effect piston displacement. Because the quantity of fuel introduced can be kept the same, since only small pulses of energy are needed, and these can be irregularly spaced to vary engine output, the fuel delivery system need not be able to vary air-fuel ratios and many complications of presently known carburetion and fuel injection devices are obviated.
Additionally, the constant fuel-air ratio can be optimized, made essentially ideal for complete combustion and thus virtually pollution free, all the time.
The fuel additions in the internal combustion engine embodiment hereof are varied in incidence, with blind strokes during which only fuel-free air is admitted, compressed and expanded in the cylinder, being substituted for fuel combustion during the power stroke portion of the cycle, from one power stroke in every cycle four strokes total) to any smaller ratio e.g., two power strokes in 40 cycles, or the like. Recalling that the inductor is kept oscillating by the resonant system, at a constant frequency but decaying amplitude, the occasional true power strokes will pulse the piston, and, thus, the inductor and restore the amplitude of oscillation, which amplitude may accordingly be sensed to assist in control of the device, i.e., a sensed decreased oscillation amplitude indicating a need for greater incidence of power strokes in the engine cycle.
A notable feature of the present device is the retention of one true advantage of the so-called rotary, or Wankel engine, over conventional reciprocating en-,
gines, namely the absence of end-of-excursion power loss as the movable part reverses direction. In my device the spring system stores energy on compression and returns it so the-end of excursion does not entail power losses heretofore associated with linear motion.
A further advantage of the present invention is that greater power is nearly instantly available, without the need of accelerating heavy metal masses and without the undue delays characteristic of turbine and diesel engines which have limited theappeal of these propulsion systems in automobiles.
Accordingly, the invention provides in an electric generator of the internal combustion type, a generator structure including an inductor adapted to be driven directly'by power strokes in the operating cycle of the engine, and spring structure reacting to said power strokes to oscillate the inductor at the frequency of mechanical resonance, between successive power strokes to generate electricity. The invention further contemplates provision of means responsiveto a predetermined decrease in the amplitude of inductor oscillation to increase the incidence of power strokes in the'operation of the engine, andthus increase power in generator output lines, and motor means and/or electrical energy storage apparatus operatively connected thereto. The' engine mentioned may be one operating in the diesel cycle and include a piston adapted to compress .air within the cylinder for spontaneous ignition upon additionof fuel, or one operating in the Otto cycle and include a spark means adapted to ignite a fuel-air mixture within the cylinder for the engine cycle power stroke.
The present generator apparatus may further include means to pass fuel, or fuel-free air into the cylinder in timed relation to the engine operating cycle and selectively to define a predetermined sequence of power strokes and nonpower strokes: respectively in the engine' operation, e.g., in fixed quantitles of fuel and .at varying ratesaccording to the stroke sequence, means to vary over time the ratio of power strokes to nonpower strokes, including, e'.g., means responsive to a predetermined decrease in the amplitude of inductor oscillation to increase the ratio of power strokes to nonpower strokes in the operation of the engine. The
fuel passing means may comprise a fuel intake port and means to predisperse fuel liquid for passage through the port.
More specifically, the invention provides in an electric generator of the internal combustion type having a cylinder and a piston, a stationary generator portion beyond the cylinder and a movable generator portion connected directly to the piston for displacement axially of the cylinder, i.e., along the axial line extending through and beyond the cylinder about a portion of which the cylinder is generated, relatively past the stationary generator portion responsive to fuel combustion in the cylinder, spring structure acting on the piston and the movable generator portion and reacting to piston displacement by a power stroke of the engine to oscillate the same at the frequency of mechanical resonance to generate alternating current of harmonic frequency, and means to maintain the resonant oscillations. The cylinder maybe provided with an inlet for combustible fuel mixture and and exhaust outlet, and the generator device further includes means to feed combustible fuel mixture or fuel-free air into the engine cylinder through the inlet in timed relation to the en-' gine operating cycle and selectively to define the above noted predetermined sequence of power strokes and nonpower strokes respectively in the engine operation.
The means to maintain resonant piston oscillations mayinclude means sensing the amplitude of piston oscillation, and means responsive to a sensed change in the amplitude to vary the ratio of power strokes to nonpower strokes in the operation of the engine by increasing or decreasing respectively the incidence of fuel combustions within the cylinder.
Additionally, in certain embodiments, the invention includes an electric generator ofthe type having an internal combustion engine comprising a pair of spaced,
axially alined, opposed cylindersand piston means axially displaceable therein responsive to fuel'combustion within one or the other of said cylinders, the generator including a magnetic inductor, e.g., comprising a-permanent magnet, or coil and magnetic core, carried by the piston means between the cylinders, and spring structure coacting with the piston means to continuously linearly oscillate the inductor at the frequency of mechanical resonance responsive to fuel'combustiondisplacement of the piston means, to generate, electricity of harmonic frequency.
More particularly, the invention contemplates an electric generator comprising a pair of spaced, opposed cylinders having a common longitudinal axis, each of the cylinders ha ving an air-inlet means, a combustible fuel inlet comprising a valve controlledinletport, and an exhaust comprising a valve controlled exhaust port; a piston in each of said cylinders, the pistons being coupled together to be displaceable jointly along the common axis in oscillating relation responsive to fuel combustion in one or the other of said cylinders; a magnetic inductor carried by thepistons between the cylinders for oscillation along a linear path parallel to the axis; an
induced current coil and magnetic core thereinbetween the cylinders and adjacent the magnetic inductor path for generation of electricity upon inductor oscillations'therepast; valve operating means, whichrmay be electrically controlled, to operate the inlet port valve and exhaust port valve of each cylinder alternately to provide therein a fuel and air mixture for combustion to displace the cylinder piston; spring structure reacting to the piston displacement to oscillate the magnetic inductor at the frequency of mechanical resonance, and means to maintain resonant frequency oscillation including means to actuate the valve operating means in timed'relation to piston oscillation responsive to a predetermined decrease in the amplitude of piston oscillation. The spring structure may be coaxial with the common cylinder axis and be secured at one end to the piston. There may further be provided means to inject fuel into the cylinder under high pressure, e.g., a fuel injector for each cylinder, in timed relation to the piston travel for fuel combustion in the diesel cycle,
thereby to thermodynamically convert the energy contained in the fuel into a pulsating force applied tothe piston. Alternatively there may be provided means to ignite the combustible mixture within the cylinder in the Otto cycle, in timed relation to the piston travel to increase the amplitude of inductor oscillation.
As noted above the generator may be provided with output lines and have a load, e.g., comprising a motor operatively connected thereto. In this embodiment, a controlled rectifier means may also be provided, arranged to cut the load from the generator in response to reduced demand for power, e.g., when slowing or operation thereof at idle. Moreover where the generator is connected to an energy storage apparatus such as a storage battery there may be provided means to rectify the current output from the generator.
The foregoing described devices are useful in the practice of the present invention in its method aspects for the generation of alternating current, such method including in one embodiment, oscillating a movable generator portion relatively past a stationary generator portion at the frequency of mechanical resonance by means of an elastic force acting on the mass of the movable portion, and pulsatingly displacing the movable generator portion with the piston of an engine in timed relation with its oscillations to maintain resonant oscillation, e.g., by sensing the amplitude of movable portion oscillations and effecting the pulsating displacing step in response to a predetermined decrease in oscillation amplitude, to restore maximum amplitude of the oscillation.
More particularly, the method comprises the generation of alternating current by oscillating aninductor linearly past a stationary magnetic core carrying an induced current coil, at the frequency of mechanical resonance, by means of springs acting in concert on opposite sides of the inductor, and occasionally displacing the inductor against the force of the springs with first and second pistons of an internal combustion engine, in timed relation with the oscillation, to maintain resonant oscillation. The invention accordingly provides a novel method of operating an internal combustion engine which includes oscillating the piston of the engine at the frequency of mechanical resonance determined by an elastic force reacting against the motion of the combined mass of the engine piston and of energy conversion means, e.g., a magnetic inductor operating in a flux field, driven by the piston, to transform kinetic en.-
ergy of the motion into potential energy storedand periodically returned to the resonant system by the elastic force, thereby avoiding end-of-excursion loss of kinetic energy. The method further contemplates pulsatingly displacing the engine piston with occasional engine power strokes and temporarily accumulating the mechanical energy thereof for release as periodic oscillant energy to the energy conversion means, sensing the am-' plitude of the periodic oscillations and initiating a complete internal combustion cycle including a power stroke, in timed relation to the mechanical oscillation, in response to decrease of oscillation amplitude below a predetermined limit; and initiating a complete internal combustion cycle including a power stroke responsive to a sensed requirement for a predetermined amount of power to be delivered through the energy conversion means.
The invention further contemplates method for the operation of a reciprocating engine including oscillating the piston of the engine at the frequency of mechanical resonance determined by an elastic force reacting against the motion of the combined mass of the engine piston and of the energy conversion means driven by the piston, to transform kinetic energy of their motion into potential energy stored and periodically returned to the resonant system by the elastic force, thereby avoiding end of excursion loss of kinetic energy. The engine piston may be pulsatingly displaced by irregularly spaced, occasional engine power strokes, and the mechanical energy thereof temporarily accumulated for release as periodic oscillant energy to the energy conversion means. The method further contemplates sensing the amplitude of the periodic oscillation and initiating power strokes by the admission and subsequent expansion of working fluids, responsive to a predetermined decrease in oscillation amplitude.
PRIOR ART It will be evident from the foregoing that the invention provides method and apparatus in which irregular, occasional, pulsating forces resulting from power strokes are converted into, and maintained at, resonant oscillation of the piston, for the generation of power where the piston is directly connected to a generator movable portion.
Other devices in the literature have involved linear generation of power and/or free piston movement, but my device to my knowledge is the first offering controlled piston oscillation, in a linear generator, and at frequencies of mechanical resonance. Among prior known devices are those disclosed in these patents being all the patents turned up in a Patent Office search: U.S. Pat. Nos. 1,785,643; 2,829,276; 2,899,565; 2904,70]; 2,936,743; 2,966,148; 3,105,153; 3,206,609; 3,234,395; and 3,510,703.
It will be noted that those patents do not purport to achieve mechanically resonating generator structure nor is any teaching made of maintaining such resonance, if even inadvertently achieved. Free piston engines are dissimilar from my apparatus in having piston movement without spring control and in accordingly being unable to resonate at any definite periodicity, if at all. Moreover, free piston engines, so called, are not converters of energy, but merely produce hot gases. And not even this output is variable, while maintaining constant oscillation frequency, unlike the present appa ratus. I
BRIEF DESCRIPTION OF THE DRAWINGS The invention .will be further described as to certain illustrative embodiments thereof, in connection with the attached drawings in which:
FIG. 1 is a block diagram of the present invention in an embodiment particularly adapted to automobile propulsion;
FIG. 2 is a view in vertical section of a single cylinder Otto cycle engine generator according to the invention;
FIG. 3 is a view like FIG. 2 of a two cylinder Otto cycle engine generator;
FIG. 4 is a view taken on line 4-4 in FIG. 3;
FIG. 5 is a graphical depiction of current output;
FIG. 6 is a schematic of a control circuit for the present generator device;
FIG. 7 is a table of engine operation in the Otto cycle with various ratios of power and nonpower strokes, to vary power generated;
FIG. 8 is a table of engine operation in the otto cycle, like FIG. 7 but with the addition of clean air intake an exhaust modes;
FIG. 9 is a view like FIG. 3, of a diesel cycle engine; and
FIG. 10 is a table like FIG. 7, but ofengine operation in the diesel cycle.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Advantages Resonance herein refers to a continuous change between potential energy and kinetic energy, substantially without loss of energy, assuming friction losses to be negligible. As is known, a resonant system comprises a mass and a spring which provides an elastic force on the mass proportional to the mass displacement. Thus, if x is assumed to be a displacement distance within the elastic range of the spring, the elastic force is kx where k is the constant of the spring employed. The frequency of resonant oscillation in this system is a function of the system mass and the k factor of the spring employed.
This invention, in the embodiment to be described here, employs resonance in a thermodynamic cycle for the'purpose of converting the chemical energy of a hydrocarbon fuel, transformed by internal combustion, into electrical energy, which, of course, can be subsequently transformed into mechanical energy, or other form of energy.
The objectives of the invention include:
Greater fuel efficiency than realized in conventional internal combustion engine devices;
More completefuel combustion, fewer unburned exhaust products and less smog generation;
Elimination of inertial losses in engine operation, to reduce mechanical energy losses to a minimum;
Longer operating life for-the engine device, through greatly reduced frictionbetween moving parts, realized by the substantial abse'ncefof lateral or normal forces between these parts;
Increased power per quantumof fuel;
' Elimination of numerous heavyv moving parts in auto-v mobilesand like vehicle's, including crankshaftstransmissions and differential components;
Modular replacement of parts subject to breakdown; and h J Higher efficiency operation by elimination ,of
heavy drive train components and greater ease ofdeceleration through absence of substantial engine inertial forces. 1
System Overview I An overview of the nature and operation of my generator device is provided in FIG. 1. Fixed portions of combustible fuel mixture, obtained as described below, enter the device thermodynamic cycle at block A. These fuel increments, which may be another working fluid such as steam, or other condensible-expandible vapor are passed to block B which is an engine having linearly movable, i.e., reciprocatory pistons for conversion of the energy of the working fluid into mechanical energy in the form piston displacement. Block C is a resonant mechanical energy tank, namely a springmass system capable of absorbing the mechanical energy of the piston displacement during a power stroke and temporarily storing it in the form of potential (elastic force) and/or kinetic (mass in motion) energy; the continuous exchange between the two forms of energy preserves it for a substantially longer time than that of the power stroke. A pulsating force from the piston displacement, block B, is thus applied to the spring-mass system, block C, which reacts, setting up a two-way interaction therebetween as shown by the arrows between blocks B and C.
Importantly, the pulsating force increments from the piston cause a periodic (resonant) response in block C, effectively converting pulses or inputs of energy irregularly or regularly supplied, into a consistent, predictable and regularized output, shown as the periodic force in FIG. 1.
In block D a linear generator of electrical energy is depicted wherein the periodic motion realized from conversion-of pulsed piston displacement into resonant oscillation is used to oscillate an inductor linearly relatively past astationary magnetic core and coil whereby a sinusoidal variationof the magnetic flux through the core is obtained and an alternating e.m.f. induced in the coils, as is known. The frequency of the current is a harmonic of the mechanical movement,,dependent on the number of poles as is known in electrical power generation technology, and in this invention, an har monic of the mechanical resonant frequency movement of the inductor. Electrical energy is thus extracted in block D from the resonantmovement in block C, pulsatingly driven by the piston in block B. The extraction ofelectricity tends to decrease the amplitude of inductor oscillation while the piston derived pulses of energy tend to increase this amplitude. Accordingly the generator reacts on the resonant energy tank, block C, as'shown. An equilibrium is reached and a stable oscillation realized when the sum of mechanical energy fed into the system by the piston,- block- B,
equals the sum of energy transformedinto electricaltor during operation, and requiredpower jinformation' fromthe accelerator or other operation control means (not shown) to vary vehicle speed (note that generator oscillation frequency does not vary with vehicle speed) at the comparator in-block E. The compared information in block E is integrated into' an output containing powerinformation fed to block F, the trigger mechanism controlling entrance of fixed portions offuel into the above-described cycle. Thus when the power information to the trigger mechanism is that more power is needed, a trigger signal is sent to block A to commence the feed of fixed portions of fuel to the engine, ,block' In addition to being power demand responsive, the trigger mechanism in block F is responsive to sensed oscillation amplitude in theblock C resonant energy tank, initiating a trigger signal for a further pulse to the resonating system when the oscillation amplitude falls below a predetermined value. A timing control is provided between the resonant energy tank in block C and the trigger mechanism in block F to ensure only synchronous initiation of pulse energy in block B, so as to avoid counterproductive displacement of the piston therein.
System Components With the foregoing summary of operational interrelationships in view, the structural and operational details of one cylinder, two cylinder, Otto cycle and diesel cycle engines, will be described together with the resonating structure and the linear electrical power generation means driven thereby according to the invention. Thereafter, an illustrative control regime for a typical embodiment will be described.
Engine Aspects Referring now to FIGS. 3 and 4, a two cylinder engine embodiment of the generator device of the invention is shown. The engine per se is generally conventional in design and materials of construction, except as noted hereinafter, and comprises specifically engine block 1 in which is formed left cylinder a and right cylinder b in spaced opposed relation, on a common longitudinal axis, each surrounded by cooling water passages 2, the cylinders each terminating in an annular flange 3, 4 respectively. The plane of the left cylinder a and right cylinder b in the drawing is different to show an exhaust port 5, and the valve arrangement 6 therefor at the left cylinder, and to show an intake port 7, fuel supply means 8, spark plug 9, and intake port valve arrangement 10 at the right cylinder, it being understood that the intake and exhaust ports and valving for each are side by side at the top of each cylinder in the embodiment illustrated. Pistons ll, 12 comprise respectively piston heads 13, 14 which may carry conventional piston rings (not shown) and rods 15, 16 connected rigidly thereto, and are adapted to fit snugly but move freely with ordinary lubrication in reciprocating relation in their respective cylinders a,'b. Rods l5, l6 terminate in'mounting plates .17, 18 respectively, inductor structure 19 being rigidly mounted-between the opposed plates, by means not shown, to be. directly connected to the pistons 13, 14. The pistons l3, 14 are thus directly and rigidly connected to the inductor structure 19 and to each other for movement as an integralunit. Typical of each engine cylinder, the left cylinder a is provided with an exhaust port 5 and an exhaust valve 20 'controlling flow of gases therethrough, the valve comprising a valve head 21, a valve stem 22 slidably received in bore 23 inthe engine blockl, and a polar plate 24. Block passageway 25 provides for water circulation at the exhaust port 5. The valve 20 is actuable as a solenoidagainst spring 20a by provision of coil 26 surrounding the valve stem 22 adjacent the polar plate 24. Burned gases or air within cylinder (1 are exhausted by application of electric current to the coil 26, by means not shown, and responsive actuation of 1 the valve 20 by the resultant magnetic flux.
Also typical of each engine cylinder, the right cylinder b is provided with an air intake port 7 a fuel injector 27, intake valve arrangement 10, spark plug 9 and water circulation passageway 28 adjacent the intake port. The intake valve 10 controls flow of air and fuel to the cylinder b and comprises a valve head 29, a valve stem 30 slidably received in bore 31 in the engine block 1, and a polar plate 32. The intake valve 10 is actuable against spring 10a as a solenoid by provision of coil 33 surrounding the valve stem 30 adjacent the polar plate 32. Incoming fuel-air mixture, or air alone as will be seen, is introduced into the cylinder b by opening of the intake valve 10, by application of electric current to the coil 33, by means not shown, and responsive actuation of the valve 10 by the-resultant magnetic flux.
Spark plug 9 is provided for ignition of fuel/air mixture within the cylinder. The fuel injector 27 comprises a restricted orifice port 34 to which fuel is supplied under pressure (not shown) and a solenoid actuated valve 36 comprising plunger 37 operating in passageway 38, surrounded by electrical coil 39 and carrying end plate 40 to selectively close and open opening 41. The fuel entering passageway 38 is jetted from port 34 by the plunger 37 or by source pressurization of the fuel and may be further vaporized by contact with hot wall 42 portion opposite the port.
The plunger 37 is operated for like periods so that each actuation delivers the same amount of fuel, but the number of actuations for a given unit of time may be varied. Complex carburetion and variable fuel injection problems are obviated, an important feature of my invention, because combustion conditions can be optimized and kept constant.
The engine therefore is an arrangement of cylinders, pistons and valves, operated in the usual sequence, but with the important addition of fixed portions of fuel.
Resonating Inductor Structure The inductor structure 19 comprises a permanent magnet 43 (or transformer laminates which may be provided with an excitation coil at 44) having a magnetic field with the North and South poles at opposite ends of the magnet. Compression springs 45, 46 are provided centered on annular flanges 3, 4 of cylinders a, b, coaxial with piston rods 15, 16 and engaged in grooves 47, 48 of mounting plates 17, 18, respectively. The size of the springs 45, 46 and their k' factor is selected' to define, with their own, the inductor and the piston mass, a resonating system. Heavy springs are desirable from a durability standpoint and such serve to permit using all the mass needed in the pistons and inductor structure. As thus located, the springs 45, 46 bias the inductor structure 19 to be equidistant from the cylinder flanges 3, 4 at the position R. Any overcenter displacement of the inductor structure 19, e.g., the shift left in FIG. 3, causes the compressed spring (e.g., spring 45) to react, and elastically return the inductor toward the center line 49 with the opposite spring 46 acting in tension, to cooperate with the compressed spring. Because, by definition, the spring-mass system employed resonates, the inductor-structure 19 will oscillate indefinitely at the frequency of mechanical resonance given an initial displacement left or right of the rest position R. The frequency of inductor structure 19 oscillation will remain substantially constant, while the amplitude, or length x of excursion, left or right will decay over time, as is characteristic of mechanically resonant systems.
Accordingly, the apparatus thus-far described is a mobile system comprising a mass-spring combination able to oscillate along its longitudinal axis at the frequency of resonance. The apparatus is desirably designed to oscillate at a frequency between about 40 and Hz although lower and higher frequencies can be used, provided only that resonance is maintained. One
advantage of the noted frequency is that piston motion will then compare with piston speeds now realized in modern automobile engines. Accordingly, no new technology is needed to adapt available auto pistons and cylinders to this invention. Moreover 60 Hz corresponds to generally available electrical power in the United States, which is an advantage in starting the present generator device, as will be explained hereinafter.
The inductor motion has been described. The generator structure includes in addition to the movable portion, the inductor 19, a stationary portion generally indicated at 50 supported by engine block 1 adjacent the inductor l9 path. The generator stationary portion 50 comprises first and second magnetic cores 51, 52
formed of transformer laminate, secured by bolts 53 (see FIG. 4), and coils 54, 55, the cores defining a narrow gap 56 with the inductor'structure 19 to ensure efficiency in the magnetic circuit defined by the opposed, movable inductor structure and the stationary cores 51, 52. The lateral (normal) force between the inductor structure 19 and the cores 51, 52, respectively, due to magnetic attraction, is equal and. opposite and thus these forces cancel each other. Friction is accordingly minimized, and can be reduced even further by an oil film in the gap 56.
In operation, the coils 54, 55 function as secondary transformer windings, with the variable magnetic flux being provided to the coils by the oscillating motion of the inductor structure 19, to cause reversal of the stationary portion core poles 57, 58, 59, and generation of a.c. in the coils which is taken off at lines 60,- 61. The generator can be reversed, becoming an oscillating motor, by application of a suitable frequency a.c. to coils, e. g., 60 H,, which will cause the inductor to oscillate, with the pistons, and'there'by' establish resonant oscillation as soon as the necessary amplitude is reached, forv stable oscillation. I Generator Output 'With reference to FIG. 5, the generator characterispiston. If x. is taken as the linear-displacement from the rest R position, atires'onanee, the vibration x,.=f(t) can be closelydescribed by thesine curves 65a, 65b, FIG.
5. The four strokes of the engine total'c ycle, namely in take (I), compression (C), power stroke (P) and exhaust (E) for eachcylinder each coincide with a change in x from a maximum to a minimum, or vice versa. Curves'65a and 65b show the phase relation typical in a two cylinder device',where power strokesare sequenced adjacently. The magnetic'flux (it produced in I the magnetic bores 51, 52 by the inductor 19 move ment shown in curve 651: exhibits a linear variation with x,- and thus, a sinusoidal-variation with time. The e.m.f. inducedxin the. coils 54, 55 will consequently be e (dda/dr) =.k"(dx/dt A reference. winding (coil) which is not loaded by any significant external imped-.
'ance can provide a voltage proportional to dx/dt shownin curve 65b. A simple integrating circuit can provide a signal proportional to x, according to k I. (dx/dt) dt kx. This signal is further used in the electronic control of the power cycle as described below.
The four-stroke (Otto) cycle of each cylinder is practically the same as that of a conventional engine. The constant frequency of oscillation, however, results in a constant cycle during which the fuel/air mixture and the timing of the spark and valve opening can be optimally adjusted. Especially, the fuel injection system becomes very simple: it injects the same fuel amount, with the same timing, during each power cycle. As described above, activation of coil 39 drives plunger 37 which in addition to opening the passageway 38, also operates as a piston to inject the fuel. In a two-cylinder system working at full power, the cycle of cylinder b is delayed by one stroke with respect to the cycle of cylinder a. The power stroke in cylinder a corresponds to the compression stroke in cylinder b, accordingly.
Electrical energy is extracted when an external load is connected to the terminals 60, 61 of the coils S4, 55. This tends to decrease and eventually stop the oscillation of the inductor 19. At the same time, however, mechanical energy is being fed into the system (two power strokes for every cycle); this tends to increase the amplitude of oscillations. As explained above, an equilibrium is reached where the oscillation is stable.
One Cylinder Embodiment Since the system is resonant, the decrease in amplitude during the non-active strokes (intake I, Compression C, and Exhaust E) is minimal in the absence of power extraction; and a one cylinder system will operate. A one cylinder system is shown in FIG. 2, where like numbers refer to corresponding functionparts.
' intake stroke (I) of fuel and air is followed by compression stroke (,C), followed bys park and a power stroke (P) as the piston is displaced byjthe fuel-air mixture combustion, followed by the exhaust stroke (E) and'so forth, repetitively..Meanwhile cylinder b is proceeding through anidentical sequence but in phased relation,
so thatcylinder a power stroke (P)is simultaneous with cylinder b compression stroke (C.).' 1
As noted, some power strokes maybe omitted. ,The' engine and inductor continue tooscillate at the reso nant'frequency, provided sufficient power pulses (pis ton to inductor) are delivered to maintain'lrequired amplitude for resonant frequency oscillation. At the 2/18.
regime for example, cylindersaand b initiate a power stroke' (P). cycle (phased) every .18 strokes, i.e.",' 14 strokes are blank between successive power stroke cy- 'cles. Thesefblank strokes are termed"n'onpower strokes and it will be seen that power output is vari able by varying the ratio of power strokes to nonpower strokes andan increase in the incidence of power strokes, i.e., relative'to nonpower strokes, increases power obtained from the generator device.
As already mentioned, the frequency of oscillation and thus the number of cycles'per second, remain constant regardless of the power required from the engine. The reduction of the power output accordingly is achieved by decreasing the number of active or power cycles and by letting the system oscillate freely in between. FIG. 7 shows exemplary possible combinations of active and passive cycles for a two-cylinder system. It is noteworthy that a reduction by a factor of and more is readily achieved, because damping of oscillations is minimal when no power is extracted from the motor. Under these conditions, only frictional forces absorb energy. Since the moving ensemble is reduced to a minimum (no crankshaft, gears, cams, etc) the frictional forces are minimal too. As shown by FIG. 7 there is a whole range of intermediate levels of power with cycles comprising from four up to 40 and more half-oscillations, each cycle having only two power strokes and the inertia of resonant oscillations providing the nonpower strokes. The electronic control to be described is designed to maintain the balance between power fed into and extracted from the system.
At this point, it should be stressed that acceleration, increase of power from a low to a maximal level, can be achieved with practically no delay. A failing of conventional diesel, battery or turbine-powered vehicles has been the lack of adequate acceleration for passenger car use, for passing or entering freely moving traffic. My generator device provides increased power and thus the ability to accelerate rapidly, virtually instantaneously. For example, if the generator device is idling, e.g., with a 2/40 cycle of FIG. 7, suddendemand for power occurs, the next cycles can be 2/4 (maximum); the only delay is a part cycle. There are no mechanical parts to be accelerated, which in addition to delaying the delivery of increased power, also absorb energy (only to give it back at a time when it is not needed as when braking). It appears unnecessary to stress further the great advantages of this principle as far as performance and economy are concerned.
During the nonactive or blank" cycles, it may be most desirable to admit clean air into the cylinders, to be kept there until the next active cycle. This way, the losses of energy by pumping action on every stroke are avoided, and so is the consumption of electrical energy in opening the valves andinitiating the spark. FIG. 8 shows exemplary possible cycles for different levels of power with clean air admission into the cylinders. It is known that combustion is more efficient in cylinders which have been flushed with clean air between cycles. This factor in the present generator device, added to the optimum and constant fuel/air ratio, timing, and other factors enumerated. above combine to' produce the cleanest burn which can practically be achieved, to produce the lowest'level of air pollution attainable with internal combustion. The inherent high efficiency of this device means that the compression ratio can be diminished while stillobtaining sufficient power from a reasonable size engineJn FIG. 8, additional operations have been added to the strokes shown in FIG. 7. Thus clean air intake'(i) and clean air exhaust (e) are added to the stroke sequence. Otherwise the operation is as described in connection with FIG. 7. Note that the clean air is shown to be retained in the cylinders during the blank (nonpower) stroke series.
Diesel Cycle As mentioned above, the principle of the invention is equally applicable to diesel cycle engines. Turning to FIG. 9 wherein like numerals refer to like parts .in FIGS. 3 and 4, a diesel engine is shown, arranged for use in the generator device of the invention. In the diesel embodiment, air is admitted, e.g., to the cylinder b, compressed by the piston 14, fuel is atomized and injected under high pressure into the compressed air by fuel injector comprising a solenoid actuated valve and plunger 71, and nozzle 72. Combustion of the resulting mixture occurs spontaneously, driving the piston from the cylinder, displacing the inductor structure 19 and initiating the resonant oscillation a.c. generation process described above, which is the same in this embodiment. Indeed, other working fluids, as earlier mentioned, usable to displace pistons or their equivalent and capable of resonant oscillation as described herein may be used to maintain resonant oscillation of the inductor structure 19 and thereby to effect the purpose of the invention. In FIG. 10, the a and b cylinders power stroke to total stroke analysis is provided for the diesel embodiment of FIG. 9; like FIGS. 7 and 8, FIG. 10 depicts the use of varying ratios of power strokes to nonpower or blank strokes, to vary power output. The asterisks in FIG. 10 refer to the time of fuel injection rather than spark discharge.
Electronic Control An-illustrative control circuit for the abovedescribed generator device is shown in FIG. 6. Reference coil 101 without external load senses the voltage e induced in the coils 54, 55 by the motion of the inductor structure 19 and provides a signal e (ddJ/dl) k(dx/dt). A Schmitt trigger 102 driven by the voltage e transforms the sine wave of e (FIG. 5) into square, standard clock pulses CPa for timing pulses of cylinder a, and CPb for timing pulses of cylinder b. FIG. 5 shows the time relation between voltage e and the inductor structure displacement x, and the clock pulses CP at outputs Q and 6 of the Schmitt trigger 102.
The voltage e is processed by an analog integrating circuit 104 which integrates the voltage e with respect to time and thus provides an output proportional to the inductor structure 19 displacement.
A source of a pre-set reference voltage X is provided at 103. X,, is set equal to the maximum voltage which can be provided by integrator 104 when the inductor l9 displacement at has an amplitude such that additional power strokes (active'engine cycles) should be initiated .and the inductor pulsed, to maintain'proper oscillation. A comparator 105 compares actual oscillation displacement x (amplitude) with the pre-set value X and provides a signal when 1: falls below X,,,. The or gate 107 turns on whenever comparator 105 is on, or whena predict signal is received signifying increased demand for power to be forthcoming, e.g., from an automobile throttle. The cycle is thus changed to a power cycle with practically no delay..The and gate 120 trans fers the signal from gate 107 so long as the emergency stop signal does not go off. If such stop signal is received (e.g., overload) all cycles are stopped, for the duration of the signal. The and gates 108 and 109 transfer the timing trigger signal, CPa and CPb respectively, when gate 120 is on, into the switching system comprising and gates l12-and 113, master-slave flip-flop 1 15 and the or gate 110. And gate 111 transfers CPa pulses received from gate 112 when the end-of-cycle signalis on and and'gate-114 functions similarly with respect to CPb puses Gate turns on whenever gate 111 or 114 is on, receiving the start-cycle signal and driving the flip-flop 115 which turns output Q on and off in sequence according to pulses CPa or CPb received indirectly through gate 110. Output 6 follows in inverted decreases.
sequence. The active cycles in cylinders a and b thus are properly alternated. An end-of-cycle signal from cycle sequence generator 116 drives gate 111 to avoid improper start-cycle signals. The cycle sequence generators 116, and 118, respectively for cylinders a and b comprise digital circuits wired to deliver pulses of the right length and in the right sequence for the active cycles of their cylinders. These sequence generators are synchronized by the CP pulses on one of inputs, and triggered by the input coming from gate 111, or gate 114, respectively.
The pulses from sequence generator 116 and 118 drive power boosters 117 and 119 wherein the power of the pulses is increased, e.g., SCRs may be used, to be fed to control lines for fuel injection, intake and exhaust valves and ignition, and clean air intake and exhaust cycles, if these latter are used.
In operation, reception of the predict signal or a signal that inductor displacement x is below the reference value, either of which signals indicate that more power needs to be supplied to the engine, will initiate more active cycles, in proper sequence. When power requirements drop, the active cycles are suppressed until at Additional Considerations The embodiment described above is only a twocylinder system but it is evident that any number of such systems and therefore any number of cylinders can be used in the same-engine. The oscillations of alternate systems should have the same frequency and desirably be 180 out of phase, in order to minimize vibrations. Interlocking of control systems and electrical parts can be readily achieved. I
The foregoing description of the internal combustion resonance motor generator device has made reference to use of this motor in an automobile, as a typical application, for which the device is highly suited. The coils which extract power may consist of several windings which can be connected in series or parallel by switches. industrial rectifiers can beused such as to obtain d.c. to drive series-type electrical motors, e.g., two or four, connected mechanically to the wheels. No special transmission is necessary, it being known that a series d.c. motor can achieve both high torque and high speed. No interlock of the wheels is needed; if one loses traction, the other motor will still have full power available. In addition','-the'cost of having four-wheel drive, withfour smaller motors, will be very reasonable.
. All ancillary systems of the engine and car are electrical, as'most of them already are. The power for them is derived directly from the engine.
- The 'servicevof. such a, car is extremely simple. The electric motors need very little service during the useful life, and the mechanical and electrical parts of the engine are so simple that, again, a minimal service will be needed. Theonlypartywhich is more delicate'is the electronic section'and this may be built-in theform of plug-in modules, well standardized, which are replace: able at service stations for a small charge..This procedure would reduce considerably the cost and inconvenience ofmaintaining the car. 7
1. In an electric generator of the internal combustion engine type, generator structure including an inductor adapted to bedriven directly by po'wer strokes in the nant oscillations.
16 the frequency of mechanical resonance between successive power strokes to generate electricity.
2. Electric generator according to claim 1 including also means responsive to a predetermined decrease in the amplitude of inductor oscillation to increase the incidence of power strokes in the operation of the engine.
3. Electric generator according to claim 1 including also means to pass fuel or fuel-free air into the cylinder in timed relation to the engine operating cycle and selectively to define a predetermined sequence of power strokes and nonpower strokes respectively in the engine operation. I
4. Electric generator according to claim 3 in which fuel is passed into the cylinder in fixed quantities and at varying rates according to said stroke sequence.
5. Electric generator according to claim 3 including also means to vary over time the ratio of power strokes to nonpower strokes in the operation of the engine.
6. Electric generator according to claim 3 including also means responsive to a predetermined decrease in the amplitude of inductor oscillation to increase the ratio of power strokes to nonpower strokes in the operation of the engine.
7. Electric generator according to claim 3 in which said fuel and air passing means includes a fuel intake port and means to predisperse fuel liquid for passage through said port. i
8. Electric generator according to claim lincluding also generator output lines and motor means operatively connected thereto.
9. Electric generator according to claim 1 including also generator output lines and electrical energy storage apparatus operatively connected thereto.
10. Electric generator according to claim 1 in which said engine operates in the diesel cycle and includes a piston adapted to compress air within the cylinder for spontaneous ignition upon addition of fuel.
11. Electric generator according to claim 1 in which said engine operates in the Otto cycle and includes spark means adapted to ignite a fuel-airmixture within the cylinder for the engine cycle power stroke.
12. In an electric generator of the internal combustion engine type having a cylinder and a piston, a stationary generator portion beyond the cylinder and a movable, generator portion connected directly to the piston folr displacement axially of the cylinder relatively past the stationary generator portion responsive to fuel combustion in the cylinder, spring structure acting on the piston and the movable generator portion and reactingto piston displacement by a powerstroke of theengine to oscillate'the same at the frequencyof me;
chanical resonance'to generatealternating current of harmonic frequency, and means to m'ain'tain saidv few- 13. Electric generator device according toclaim 12 in which said cylinder is provided with an inlet for com-- bustible fuel mixture andan exhaust outlet, andsaid device including also means to feed combustible fuel mixture or fuel-free air into the cylinder through said inlet in timed relation to the engine operating cycle and selectively to define a predetermined sequence 'of power strokes and non-power strokes respectively in the engine operation.
14. Electric generator device according to claim in which the means to maintain resonant piston oscillation includes means sensing the amplitude of piston oscillation, and means responsive to a sensed change in said amplitude to vary the ratio of power strokes to nonpower strokes in the operation of the engine by increasing or decreasing respectively the incidence of fuel combustions within the cylinder.
15. Electric generator according to claim 14 in which said engine operates in the diesel cycle, said piston being adapted to compress air within the cylinder sufficiently for spontaneous ignition of fuel injected thereinto.
16. Electric generator according to claim 14 in which said engine operates in the Otto cycle and includes spark means adapted to ignite a fuel-air mixture within the cylinder for the engine cycle power stroke.
17. An electric generator of the type having an internal combustion engine comprising a pair of spaced, axially alined, opposed cylinders and piston means axially displaceable therein responsive to fuel combustion within one or the other of said cylinders, said generator including a magnetic inductor carried by the piston means between said cylinders, and spring structure coacting with the piston means to continuously linearly oscillate the inductor at the frequency of mechanical resonance responsive to fuel combustion-displacement of the piston means, to generate electricity of harmonic frequency.
18. Electric generator according to claim 17 in which said magnetic inductor comprises a permanent magnet.
19. Electric generator according to claim 17 in which said magnetic inductor comprises a coil and magnetic core.
20. An electric generator comprising a pair of spaced, opposed cylinders having a common longitudinal axis, each of said cylinders having an air inlet means, a combustible fuel inlet comprising a valve controlled inlet port, and an exhaust comprising a valve controlled exhaust port; a piston in each of said cylinders, said pistons being coupled together to be displaceable jointly along said axis in oscillating relation responsive to fuel combustion in one or the other of said cylinders; a magnetic inductor carried by the pistons between the cylinders for oscillation along a linear path parallel to said axis; an induced current coil and magnetic core therein between said cylinders and adjacent the magnetic inductor path for generation of electricity upon inductoroscillations therepast; valve operating means to operate the inlet port valve and exhaust port valve of each cylinder alternately to provide therein a fuel and air mixture for combustion to displace the cylinder piston, and in sequence to exhaust combustion products; spring structure reacting-to said piston displacement to oscillate said magnetic inductor at the frequency of mechanical resonance, and means to maintain said resonant frequency oscillation including means to actuate the valve operating means in timed relation to piston oscillation responsive to a predetermined decrease in the amplitude of piston oscillation.
21. Electric generator according to claim 20 including also means to ignite said mixture within the cylinder in timed relation to the piston travel to increase the amplitude of inductor oscillation.
22. Electric generator according to claim 20 including also means to inject fuel into the cylinder under high pressure in timed relation to the piston travel for fuel combustion, thereby to thermodynamically convert the energy contained in said fuel into a pulsating force applied to said piston.
23. Electric generator according to claim 20 in which the valve operating means is electrically controlled.
24. Electric generator according to claim 20 including also fuel injector means for each cylinder for injection of fuel under pressure for combustion in said cylinder.
25. Electric generator according to claim 20 in which the spring structure is coaxial with the common cylinder axis and is secured at one end to the piston.
26. Electric generator according to claim 25 including also generator output lines and a load comprising motor means operatively connected thereto.
27. Electric generator according to claim 26 including also generator output lines and electrical energy storage apparatus operatively connected thereto.
28. Electric generator according to claim 26 including also a load and controlled rectifier means arranged to cut the load from the generator in response to reduction in power demand.
29. Electric generator according to claim 27 including also means to rectify the current output from the generator.
30. Electric generator according to claim 24 including also means operating the fuel injection means in timed relation to the engine operating cycle and selectively to define a predetermined sequence of power strokes and non-power strokes respectively in the engine operation.
31. Electric generator according to claim 30 including also means responsive to a predetermined decrease in the amplitude of inductor oscillation to increase the ratio of power strokes to nonpower strokes in the operation of the engine.
32. Electric generator according to claim 25 including also means to pass fuel or fuel-free air intothe cylinder in timed relation to the engine operating cycle and selectively to define a predetermined sequence of power strokes and nonpower strokes respectively in the engine operation.
33. Electric generator according to claim 32 including also means responsive to a predetermined decrease in the amplitude of inductor oscillation to increase the ratio of power strokes to nonpower strokes in the operation of the engine.
34. Method for the generation of alternating current,
which includes oscillating a movable generator portion relatively past a stationary generator portion at the frequency of mechanical resonance by means of an elastic force acting on the mass of said movable portion, and pulsatingly displacing the movable generator portion with the piston of an engine in timed relation with said oscillations to maintain resonant oscillation.
35. Method according to claim 34 including also sensing the amplitude of movable portion oscillations and effecting the pulsating displacing step in response to a predetermined decrease in oscillation amplitude, to restore maximal amplitude of said oscillation;
36. Method for the generation of alternating current which includes oscillating an inductor linearly past a stationary magnetic core carrying an induced current coil at the frequency of mechanical resonance by means of springs acting in concert on opposite sides of the inductor, and occasionally displacing the inductor against the force of the springs with first and second pistons of an internal combustion engine, in timed relation with said oscillation to maintain resonant oscillation.
37.'Method for the operation of an internal combustion engine which includes oscillating the piston of said engine at the frequency of mechanical resonance determined by an elastic force reacting against the motion of the combined mass of the engine piston and of energy conversion means driven by the piston to trans-v initiating a complete internal combustion cycle includ-' ing a power stroke, in timed relation to said mechanical oscillation, in response to decrease of said amplitude below a predetermined limit.
40. Method according to claim 39 including also initiating a'complete internal combustion cycle including a power stroke responsive to a sensed requirement for a predetermined amount of power to be delivered I through said energy conversion means.
' 41. Method for the operation of areciprocating engine including oscillating the piston ofsaid'engine at the frequency of mechanical resonance determined by an elastic force reacting against the motion of the combined mass of the engine piston and of energy conversion means driven by the piston to transform kinetic energy of their motion into potential energy stored and periodically returned to the resonant system by said elastic force, therebyavoiding end-of-excursion loss of kinetic energy. 42. Method according to claim 41 including also pul satingly displacing the engine piston with irregularly spaced engine power strokes, temporarily accumulating the mechanical energy thereof for release as periodic oscillant energy to the energy conversion means. 43. Method according to'claim 42 including also sensing the amplitude of said periodic oscillation and initiating power-strokes of the admission and subsequent expansion of working fluids responsive to a predetermined decrease in said amplitude.
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