Ed Gray Variant by G.M. -- Prototype 1

Ed Gray Motor Variant -- Open Source Project
Sponsored by Pure Energy Systems
Permanent Magnet / Pulsed DC Electromagnet Motor - Generator

Status: Project commenced May 26, 2004.  Claim to working OU device by Gary Magratten (not yet rigorously verified).  Plans [were] gradually being uploaded here.  As of Oct. 18, 2006, see http://www.coldelectricity.info/

Warning: high voltage, high current, laser switching

You are here:
PureEnergySystems.com > Open Sourcing > Ed Gray Motor > Patents > US Patent 3,890,548 Edwin Gray

US Patent 3,890,548 Edwin Gray
"Pulsed Capacitor Discharge Electric Engine"

June 17, 1975

Click here to view entire patent (PDF)

     "I think we should post the two Gray patents to provide a firm foundation for this project as it may develop into a project for a motor suitable for an electric vehicle as Gray intended. Both these patents are expired, but they are often referred to in my work." -- G.M.

United States Patent


[11]       3,890,548
[45] June 17, 1975

[75] Inventor: Edwin V. Gray, Northridge, Calif.
[73] Assignee: Evgray Enterprises, Inc., Van Nuys, Calif.
[22] Filed: Nov. 2, 1973
[21] Appl.No.: 412,415
[52] U.S. Cl

318/139; 318/254;
318/439; 310/46

[51] Int. Cl.

H02p 5/00

[58] Field of Search

310/46, 5, 6; 318/194, 318/439, 254, 139; 320/1; 307/110


 References Cited

2,085,708 6/1937 Spencer 318/194
2.800,619 7/1957 Brunt 318/194
3,579,074 5/1971 Roberts . 320/1
3,619,638 11/1971 Phinney 307/110

Frungel, High Speed Pulse Technology, Academic Press Inc., 1965, pp. 140—148.

Primary Examiner—Robert K. Schaefer
Assistant Examiner—John I. Feidhaus
Attorney. Agent, or Firm—Gerald L. Price

There is disclosed herein an electric machine or engine in which a rotor cage having an array of electromagnets is rotatable in an array of electromagnets, or fixed electromagnets are juxtaposed against movable ones. The coils of the electromagnets are connected in the discharge path of capacitors charged to relatively high voltage and discharged through the electromagnetic coils when selected rotor and stator elements are in alignment, or when the fixed electromagnets and movable electromagnets are juxtaposed. The discharge occurs across spark gaps disclosed in alignment with respect to the desired juxtaposition of the selected movable and stationary electromagnets. The capacitor discharges occur simultaneously through juxtaposed stationary movable electromagnets wound so that their respective cores arc in magnetic repulsion polarity, thus resulting in the forced motion of movable electromagnetic elements away from the juxtaposed stationary electromagnetic elements at the discharge, thereby achieving motion. In an engine, the discharges occur successively across selected ones of the gaps to maintain continuous rotation. Capacitors are recharged between successive alignment positions of particular rotor and stator electromagnets of the engine.

18 Claims, 19 Drawing Figures

FIG. 1 is an explanatory schematic diagram of a capacitor charging and discharging circuit utilized in the present invention;

FIG. 2 is a block diagram of an exemplary engine system according to the invention;

FIG. 3 is a perspective view of a typical engine system according to the invention, coupled to an automotive transmission;

FIG. 4 is an axial sectional view taken at line 4—4 in FIG. 3;

FIG. 5 is a sectional view taken at line 5—5 in FIG. 4

FIGS. 6 and 7 are fragmentary sectional views, corresponding to a portion of FIG. 5, illustrating successive advanced positions of the engine rotor therein;

FIG. 8 is an exploded perspective view of the rotor and stator of the engine of FIGS. 3 and 4;


FIG. 9 is a cross-sectional view taken at line 9—9 of FIG. 4;

FIG. 10 is a partial sectional view, similar to the view of FIG. 9, illustrating a different configuration of electromagnets in another engine embodiment of the invention;

FIG. 11 is a sectional view taken at line 11—11 in FIG. 3, illustrating the control head or novel speed change controlling system of the engine;

FIG. 12 is a sectional view, taken at line 12—12 in FIG. 11, showing a clutch pLate utilized in the speed change control system of FIG. 11;

FIG. 14 is a sectional view, taken at line 14—14 in FIG. 11, showing a clutch plate which cooperates with the clutch plate of FIG. 12;

FIG. 13 is a fragmentary view, taken at line 13—13 in FIG. 12;

FIG. 15 is a fragmentary sectional view taken at line 15—15 of FIG. 13;

FIG. 16 is a perspective view of electromagnets utilized in the present invention;

FIG. 17 is a schematic diagram showing cooperating mechanical and electrical features of the programmer portion of the invention;

FIG. 19 is a developed view, taken at line 19—19 of FIG. 11, showing the locations of displaced spark gap elements of the speed changing mechanism of an engine according to the invention.

FIG. 18 is an electrical schematic diagram of an engine according to the invention, showing the electrical relationships of the electromagnetic components embodying a new principle of the invention; and


1. Field of the Invention

There is no known engine or motor operated on the principle of the present invention, that a capacitor charged to a relatively high voltage from a low-voltage d-c source is discharged across a spark gap to provide current through motor drive coils in the discharge path, these being solenoids which generate motion by magnetic repulsion of juxtaposed pairs of cores. The solenoids are preferably configured in motor and stator assemblies to effect motion of the rotor element with respect to the stator.

The present invention utilizes this principle to provide a rotary motion machine or engine which can develop considerable torque through the magnetic repulsion action of rotor and stator cores wound with coils through which capacitors are discharged synchronously with the positioning of the rotor coils opposite particular stator coils. Similarly, a linear action can be achieved with a stationary electromagnet juxtaposed against a movable electromagnet and the movable electromagnet can perform work with a tool or piston attached thereto.

A novel control mechanism is associated with the rotor is the engine to position discharge elements appropriately to create the desired discharge through the electromagnet coils when the juxtaposed rotor and stator electromagnets are in alignment. The electromagnets in the stator and rotor are so arranged that the control mechanism can advance or retard the discharge points relative to rotor-stator positions for control of rotational speed.
The discharge overshoot or back e.m.f. from the collapsing fields in the coils from the capacitor discharge is used to energize external batteries for conservation of power. The recovered energy thus stored may be used to operate equipment associated with the engine or motive force producing device.

The engine or rotary electric machine of the invention is believed to operate on the principle of conservation of energy, in that once rotation is achieved, current is needed only at the instant of a capacitor discharge in order to advance the rotor. The rotor moves to the next discharge point on the inertia of the repulsion action. The capacitor is recharged during the interval and stores the energy until discharge at the next rotor-stator coil coincidence. Thus, the new engine produces torque and stores the excess energy for subsequent use.

In a linear motion device according to the invention, only a single pulse discharge is needed to perform work.

The applications of the engine include use as an electric automotive engine which is economical and which can regenerate a part of the energy consumed to provide power for other loads in the automotive electric vehicle. As a linear actuator an economical use of power is possible because each stroke will result from a single discharge pulse of a capacitor through a coil.

2. Prior Art

Heretofore, electric engines or motors have operated on the principle that a conductor carrying a current in a magnetic field tends to move perpendicularly to that field; the electromagnetic torque developed by an armature or rotating portion of the motor is proportional to the magnetic flux in the stationary field and to the armature current.
In direct current motors the field is created by current through two or more field coils disposed in opposing magnetic relationship in the motor casing, while current through a rotatable armature positioned in the field is alternatingly reversed in polarity to provide continuous motion. The polarity reversing mechanism is a commutator. Some d-c motors have their field windings electrically in parallel with the rotor armature winding and are called “shunt-wound” motors. Other d-c motors have field and armature windings connected in series. In both series and shunt motors commutators are used for reversing the magnetic polarity of the armature to maintain rotation within the field.

A third type of d-c motor utilizes a permanent magnet field so that the operating current passes only through the armature winding. Such motors also use polarity reversing commutators to maintain direction of rotation. Reversal of direction of motion is effected by reversing the polarity of applied d-c potential.

Control of speed of d-c motors is accomplished basically by decrease or increase of magnetic field flux or the current through the armature. Either or both of these effects can be accomplished by raising or lowering the applied potential. In shunt motors, a series resistance may be varied to produce speed changes. In a permanent magnet motor or series motor, speed variation is best accomplished by voltage variation with a variable resistance in series with the motor d-c supply.

In alternating current motors, as is well known, a rotating magnetic field is created in the stator, and the rotor may be wound with as many poles as there are in the stator, with terminals connected with slip rings, or the rotor may consist of solid bars shorted by rings on each end to form a “squirrel cage” configuration. The speed of an a-c motor depends on the frequency of the applied a-c energy, if the motor is synchronous.

“Universal” motors are operable on either a-c or d-c energy.

In stepping motors, a rotor is moved from one pole to the next adjacent pole with each application of current, the rotor remaining at that position until a next application of current. This is accomplished by switching the current on and off or by pulsing the current. Examples of stepping motors are described in U.S. Pat. No. 3,467,902 to Shimizu, et al., U.S. Pat. No. 3,462,667 to Jackson, and U.S. Pat. No. 3,599,069 to Welch.

Operation of the a-c and d-c motors described above involves the consumption of substantial electric current. These motors can generate electric current when driven externally by a mechanical force. External energy to rotate the generator rotors can be provided by hydroelectric and steam sources or by other electric motors. In some of these systems, a d-c motor source drives an a-c generator for conversion of d-c energy to a-c energy or a d-c motor may drive a d-c generator which delivers a higher voltage than the source.

An extensive prior art search by the applicant uncovered no capacitor-discharge-operated motor resembling that of the present invention. All motors of the patents located in the search employed direct electrical connection between coils and electric power sources. Where selective switching is involved, semiconductor devices are employed, such as silicon-controlled rectifiers, Capacitors are used only for starting and phasing purposes, and not for basic motor operation from the discharge thereof, as in this invention.


This invention relates to electric motors or engines, and more particularly to a new electric machine including electromagnetic poles in a stator configuration and electromagnetic poles in a rotor configuration wherein in one form thereof the rotor is rotatable within the stator configuration and where both are energized by capacitor discharges through rotor and stator electromagnets at the instant of the alignment of a rotor electromagnet with a stator electromagnet. The rotor electromagnet is repelled from the stator electromagnet by the discharge of the capacitor through the coils of both the stator and rotor electromagnets at the same instant.

In an exemplary rotary engine according to this invention, rotor electromagnets may be disposed 1200 apart on a central shaft and major stator electromagnets may be disposed 400 apart in the motor housing about the stator periphery. Other combinations of rotor elements and stator elements may be utilized to increase torque or rotation rate.

In another form, a second electromagnet is positioned to one side of each of the major stator electromagnets on a center line 13Y3° from the center line of the stator magnet, and these are excited in a predetermined pattern or sequence. Similarly to one side of each major rotor electromagnet is a second electromagnet spaced on a I 3’A° center line from the major rotor electromagnet. Electromagnets in both the rotor and stator assemblies are identical, the individual electromagnets of each being aligned axially and the coils of each being wired so that each rotor electromagnetic pole will have the same magnetic polarity as the electromagnet in the stator with which it is aligned and which it is confronting at the time of discharge of the capacitor.

Charging of the discharge capacitor or capacitors is accomplished by an electrical switching circuit wherein electrical energy from a battery or other source of d-c potential may be applied in alternating polarity to ignition coils or other voltage step-up arrangements from which a high voltage d-c potential is derived through rectification by diodes.

The capacitor charging circuit comprises a pair of high frequency switchers which feed respective automotive-type ignition coils employed as step-up transformers. The “secondary” of each of the ignition coils provides a high voltage square wave to a half-wave rectifier to generate a high voltage output pulse of d-c energy with each switching alternation of the high frequency switcher. Only one polarity is used so that a unidirectional pulse is applied to the capacitor bank being charged.

Successive unidirectional pulses are accumulated on the capacitor or capacitor bank until discharged. Discharge of the bank of capacitors occurs across a spark gap by arc-over. The gap spacing determines the voltage at which discharge or arc-over occurs. An array of gaps is created by fixed elements in the engine housing and moving elements positioned on the rotor shaft. At the instant when the moving gap elements are positioned opposite fixed elements during the rotor rotation, a discharge occurs through the coils of the aligned rotor and stator electromagnets to produce the repulsion action between the stator and rotor electromagnet cores.

A plurality of fixed gap elements are arrayed in the motor housing to correspond to the locations of the stator electromagnets in the housing. The rotor gap elements correspond to the positions of the rotor electromagnets on the rotor so that at the instant of correct alignment of the gaps the capacitors are discharged to produce the necessary current through the stator and rotor coils to cause the electromagnets to repel one another.
The charging circuits are arranged in pairs, and are such that the discharge occurs through both rotor and stator windings of the electromagnets, which are opposite one another when the spark gap elements are aligned and arc-over.

The speed of the rotor can be changed by means of a clutch mechanism associated with the rotor. The clutch shifts the positions of the rotor gap elements so that the discharge will energize the stator coils in a manner to advance or retard the time of discharge with respect to the normal rotor/stator alignment positions. The discharge through the rotor and stator then occurs when the rotor has passed the stator 6W for speed advance.

By causing the discharge to occur when the rotor position is approaching the stator, the repulsion pulse occurs 6W before the alignment position of the rotor and stator electromagnets, thus stowing the speed.

The clutch mechanism for aligning capacitor discharge gaps for discharge is described as a control head. It may be likened to a firing control mechanism in an automotive combustion engine in that it “fires” the electromagnets and provides a return of any discharge overshoot potential back to the battery or other energy source.

The action of the control head is extremely fast. From the foregoing description, it can be anticipated that an increase in the speed or a decrease in speed of rotation can occur within the period in which the rotor electromagnet moves between any pair of adjacently located electromagnets in the stator assembly, which are 40° apart in the exemplary engine according to the invention. Thus, speed changes can be effected in a maximum of one-ninth of a revolution.

The rotor speed-changing action of the control head and its structure are believed to be further novel features of the invention, in that they maintain normal 1200 firing positions during uniform speed or rotation conditions, but shift to ±6W longer or shorter intervals for speed change by the novel shift mechanism in the rotor clutch assembly.

Accordingly, the preferred embodiment of this invention is an electric rotary engine wherein motor torque is developed by discharge of high potential from a bank of capacitors through stator and rotor electromagnet coils when the electromagnets are in alignment. The capacitors are charged from batteries by a switching mechanism, and are discharged across spark gaps set to achieve the discharge of the capacitor charge voltage through the electromagnetic coils when the gaps and predetermined rotor and stator electromagnet pairs are in alignment.

Exemplary embodiments of the invention are herein illustrated and described. These exemplary illustrations and description should not be construed as limiting the invention to the embodiments shown, because those skilled in the arts appertaining to the invention may conceive of other embodiments in the light of the description within the ambit of the appended claims.


[Inserted above after each drawing -- SDA.]


As hereinbefore mentioned, the basic principle of operation of’ the engine of the invention is the discharge of a capacitor, across a spark gap through an inductor. When a pair of inductors is used, and the respective magnetic cores thereof are arranged opposite and another in magnetic polarity repulsion relation, the discharge through them causes the cores to repel each other with considerable force.

Referring to the electrical schematic diagram of FIG. 1, a battery 10 energizes a pulse-producing vibrator mechanism 16, which may be of the magnetic type incorporating an armature 15 moving between contacts 13 and 14, or of the transistor type (not shown) with which a high frequency bipolar pulsed output is produced in primary 17 of transformer 20. The pulse amplitude is stepped-up in secondary 19 of transformer 20. Wave form 19a represents the bidirectional or bipolar pulsed output. A diode rectifier 21 produces a unidirectional pulse train, as indicated at 21a, to charge capacitor 26. A delay coil 23 is connected in series with the unipolar pulsed output to capacitor 26. Successive unidirectional pulses of wave 21a charge capacitor 26 to a high level, as indicated at 26a, until the voltage amplitude at point A reaches the breakdown potential of spark gap 30. At the breakdown of spark gap 30, capacitor 26 discharges across the arc created through the inductor coil 28. A current pulse is produced which magnetizes core 28a. Simultaneously, another substantially identical charging system 32 produces a discharge through inductor 27 across spark gap 29 to magnetize core 27a. Cores 28a, 27a are wound with coils 28, 27 so that their magnetic polarities are the same. As the cores 27a, 28a confront one another, they tend to fly apart when the discharge occurs through coils 27 and 28 because of repulsion of identical magnetic poles, as indicated by arrow 31. If core 28a is fixed or stationary and core 27a is movable, then core 27a may have tools 33 attached to it to perform work when the capacitor discharges.

Referring to FIGS. I and 2, a d-c electrical source or battery 10 energizes pulsators 36 (including at least two vibrators 16 as previously described) when switch 11 between the battery 10 and pulsator 36 is closed, to apply relatively high frequency pulses to the primaries of transformers 20. The secondaries of transformers 20 are step-up windings which apply bipolar pulses, such as pulses 19a (FIG. 1) to the diodes in converter 38. The rectified unidirectional pulsating output of each of the diodes in converter 38 is passed through delay coils 23,24, thus forming a harness 37 wound about the case of the engine, as hereinafter described, which is believed to provide a static floating flux field. The outputs from delay lines 37 drive respective capacitors in banks 39 to charge the capacitors therein to a relatively high charge potential. A programmer and rotor and stator magnet control array 40,41,42 is formed by spark gaps positioned, as hereinafter described, so that at predetermined positions of the rotor during rotation of the engine, as hereinafter described, selected capacitors of capacitor banks 39 will discharge across the spark gaps through the rotor and stator electromagnets 43, 44. The converters 38, magnetic harness 37, capacitor banks 39, programmer 40, and controls 41, 42 from a series circuit path across the secondaries of transformers 20 to the ground, or point of reference potential, 45. The capacitor banks 39 are discharged across the spark gaps of programmer 40 (the rotor and stator magnet controls 41,42). The discharge occurs through the coils of stator and rotor electromagnets 43, 44 to ground 45. Stator and rotor electromagnets are similar to those shown at 27, 27o, 28, 28a in FIG. 1.

The discharge through the coils of stator and rotor electromagnets 43, 44 is accompanied by a discharge overshoot or return pulse, the output of which is applied in an appropriate polarity to a secondary battery lOa to store this excess energy. The overshoot pulse returns to battery lOa because after discharge the only path open is that to battery IOa, since the gaps in 40, 41 and 42 have broken down, because the capacitors in banks 39 are discharged and have not yet recovered the high voltage charge from the high frequency pulsers 36 and converter rectifier units 38.

In the event of a misfire in the programmer control circuits 40, 41, 42, the capacitors are discharged through a rotor safety discharge circuit 46 and returned to batteries 10—IOa, adding to their capacity. The circuit 46 is connected between the capacitor banks 39 and batteries 10, lOa.

Referring to FIG. 3, a motor or engine 49 according to the present invention is shown connected with an automotive transmission 48. The transmission 48 represents one of many forms of loads to which the engine may be applied. A motor housing 50 encases the operating mechanism hereinafter described. The programmer 40 is axially mounted at one end of this housing. Through apertures 51, 52 a belt 53 couples to a pulley 57 (not shown in this view) and to an alternator 54 attached to housing 50. A pulley 55 on the alternator has two grooves, one for belt 53 to the drive pulley 58 on the shaft (not shown) of the engine 49, and the other for a belt 58 coupled to a pulley 59 on a pump 60 attached to housing 50. A terminal box 61 on the housing interconnects means between the battery assembly 62 and motor 49 via cables 63 and 64.

An intake 65 for air is coupled to pump 60 via piping 68, 69 and from pump 60 via tubing or piping 66, 70 to the interior of housing 50 via coupling flanges 67 and 71. The air flow tends to cool the engine, and the air may preferably be maintained at a constant temperature and humidity so that a constant spark gap discharge condition is maintained. A clutch mechanism 80 is provided on programmer 40.

Referring to FIGS. 4, 5 and 9, rotor 81 has spider assemblies 83, 84 with three electromagnet coil assembly sets mounted thereon, two of which are shown in FIG. 4, on 85 at 85a and 85b, and on 86 at 86a and 86b. One of the third electromagnet coil assemblies, designated 87a, is shown in FIG. 5, viewed from the shaft end. As more clearly shown in the perspective view of FIG. 8, a third spider assembly 88 provides added rigidity and a central support for the rotor mechanism on shaft 81.

The electromagnet sets 85a and 85b, 86a and 86b, 87a and 87b, disposed on rotor 81 and spiders 83, 84, and 88 each comprise pairs of front units 85a, 86a, 87a and pairs of rear units 85b, 86b, 87b. Each pair consists of a major electromagnet and a minor electromagnet, as hereinafter described, which are embedded in an insulating material 90, which insulates the electromagnet coil assemblies from one another and secures the electromagnets rigidly in place on the spider/rotor cage 81, 83, 84, 88.

The interior wall 98 of housing 50 is coated with an electrically insulating material 99 in which are embedded electromagnet coils, as hereinafter described, and the interiors of end plates 100, 101 of the housing 50. On the insulating surface 98 of housing 50 is mounted a series of stator electromagnet pairs 104a, identical with electromagnet pairs 85a, 86a, 87a, etc. Electromagnet pairs such as 104a or 105a are disposed every 400 about the interior of housing 50 to form a stator which cooperates with the rotor 8 1—88. An air gap 110 of very close tolerance is defined between the rotor and stator electromagnets, and air from pump 65 flows through this gap.

[scanned/OCR to here; May 28, 2004]

In Table I, the leftmost column depicts the location of each rotor arm 85, 86, 87 at an arbitrarily selected step No. 1 position. For example, in step 1 rotor arm 85 has a minor stator and minor rotor electromagnet in alignment for capacitors to discharge through them Simultaneously at the l33i° position.

Similarly, in step 1 rotor arm 86 is at the 1 33’h° position with a minor rotor and minor stator electromagnet in alignment for discharge. Simultaneously, rotor arm 87 is at the 253 Y3° position with a minor rotor and minor stator in alignment for capacitor discharge there- through. The other steps of the sequence are apparent from Table I, for each position of the three rotor arms at any step and the juxtapositions of respective stator and rotor electromagnet elements at that position.

In the simplified motor arrangement shown in schematic form in FIG. 18, with single electromagnet configuration the alignment is uniform and the discharge sequences follow sequentially.

As hereinbefore mentioned, a change in speed is effected by displacing the stator spark gap terminals on the rotor (shown at 236 in FIGS. 17 and 18) either counter-clockwise or clockwise 6%° so that the discharge position of the stator electromagnets is dis-

[scanned/OCR to here; May 28, 2004]

Click here to view entire patent (PDF)

See also


Page created by Sterling D. Allan, May 28, 2004
Last updated August 16, 2004


Search WWW
ADVISORY: With any technology, you take a high risk to invest significant time or money unless (1) independent testing has thoroughly corroborated the technology, (2) the group involved has intellectual rights to the technology, and (3) the group has the ability to make a success of the endeavor.

Battery Reconditioning -- Start Your Own Niche Business

Google Optimization
Why honesty is the best policy.

News (RSS) • Open SourcingPrivacy StatementAboutContact

PESWiki Departments:
LatestDirectoryCongressTop 100Open SourcingPowerPedia

PES Network, Inc.
Copyright © 2003 - 2006