Electromagnetic linear generator and shock absorber

• US 6,952,060 B2
• Filed: 05/07/2001
• Issued: 10/04/2005
• Est. Priority Date: 05/07/2001
• Status: Expired due to Term

• Current Assignee: Trustees of Tufts College
• Original Assignee: Trustees of Tufts College
• Inventors: Zerigian, Peter, Goldner, Ronald B.
• Primary Examiner(s): Mullins, Burton S.
• Assistant Examiner(s): Mohandesi, Iraj A.
• Application Number:
  US09/850,412
• Publication Number:
  US 20030034697A1
• Time in Patent Office: 1,611 Days
• Field of Search: 310/12, 310/13, 310/15, 310/154.01, 310/152, 310/266, 310/154.02, 310/154.05, 310/154.45, 290/1.A
• US Class Current: 310/12.13
• CPC Class Codes: B60G 17/0157 non-fluid unit, e.g. electric motor
• CPC Class Codes: B60G 2202/42 Electric actuator
• CPC Class Codes: B60G 2300/60 Vehicles using regenerative power
• CPC Class Codes: B60G 2600/26 Electromagnets; Solenoids
• CPC Class Codes: F16F 15/03 using magnetic or electromagnetic means F16F9/53, F16F15/005 take precedence
• CPC Class Codes: H02K 35/04 with moving coil systems and stationary magnets

Abstract

An electromagnetic linear generator and regenerative electromagnetic shock absorber is disclosed which converts variable frequency, repetitive intermittent linear displacement motion to useful electrical power. The innovative device provides for superposition of radial components of the magnetic flux density from a plurality of adjacent magnets to produce a maximum average radial magnetic flux density within a coil winding array. Due to the vector superposition of the magnetic fields and magnetic flux from a plurality of magnets, a nearly four-fold increase in magnetic flux density is achieved over conventional electromagnetic generator designs with a potential sixteen-fold increase in power generating capacity. As a regenerative shock absorber, the disclosed device is capable of converting parasitic displacement motion and vibrations encountered under normal urban driving conditions to a useful electrical energy for powering vehicles and accessories or charging batteries in electric and fossil fuel powered vehicles. The disclosed device is capable of high power generation capacity and energy conversion efficiency with minimal weight penalty for improved fuel efficiency.

Claims

1. A linear electromagnetic generator for providing electrical power from intermittent reciprocating linear motion comprising:

a central magnet array assembly comprised of

a central magnet array comprising a plurality of axially-aligned, stacked cylindrical magnets having like magnetic poles facing one another,

a plurality of high magnetic permeability, high saturation magnetization, central cylindrical spacers positioned at each end of said stacked central magnet array and between adjacent stacked central magnets, and

a magnet array support for mounting said magnets and said spacers;

an inner coil array comprised of a plurality of concentric cylindrical coil windings positioned adjacent to said central spacers and said magnetic poles of said central magnets, said inner coil windings surrounding an outside perimeter of said central spacers, said inner coil array mounted on a movable coil support, said movable coil support providing for reciprocating linear motion of said coil array relative to said magnet array; and

an outer magnet array assembly comprised of

an outer magnet array comprising a plurality of axially-aligned, stacked concentric toroidal magnets having like magnetic poles facing each other, said outer magnet array surrounding said inner coil array, said stacked outer magnets being aligned and positioned substantially coplanar with said stacked central cylindrical magnets with the magnetic poles of said outer magnets aligned with and facing opposing magnetic poles of said central cylindrical magnets, and

a plurality of high permeability, high saturation magnetization, outer concentric toroidal spacers positioned at each end of said stacked outer magnet array and between adjacent stacked outer magnets,

said outer magnet array assembly attached to said magnet array support;

wherein a predetermined location, configuration and orientation of said central magnet magnetic poles, said central spacers, said inner coil windings, said outer magnet magnetic poles and said outer spacers provide for superposition of a radial component of a magnetic flux density from a plurality of central and outer magnets to produce a maximum average radial magnetic flux density in the inner coil windings.

2. The device of claim 1 wherein the resultant average radial magnetic flux density in each inner coil produced by the superposition of a plurality of magnetic fields is approximately four times the average radial flux density produced in each coil by each individual magnet and wherein movement of each coil relative to said inner and outer magnet arrays generates approximately sixteen times the electrical power produced by the movement of each coil relative to each magnet.

3. The device of claim 1 wherein said central and outer magnets comprise magnetic materials selected from the group consisting of iron, neodymium, boron, samarium, strontium, cobalt, nickel, aluminum and their alloys, said inner and outer spacers comprise a ferromagnetic material selected from the group consisting of iron, nickel, cobalt and their alloys, and said inner coils comprise insulated copper wire windings.

4. The device of claim 1 further comprising a voltage conditioning circuit electrically connected to said coil windings, said circuit comprising a ferrite core transformer, a full wave rectifier bridge, a capacitor and a Zener diode, said voltage conditioning circuit providing a useful output voltage and current to an external electrical load.

5. The device of claim 1 further comprising an array of outer concentric cylindrical coil windings positioned adjacent to said outer spacers, said outer coil winding height and width being substantially equal to said inner coil winding height and width, said outer coil windings surrounding an external perimeter of said outer spacers, said outer coil array mounted on said movable coil support,

wherein a predetermined location, configuration and orientation of said outer magnet magnetic poles, said outer spacers and said outer coil windings provide for superposition of a radial component of a magnetic flux density from a plurality of outer magnets to produce a maximum average radial magnetic flux density in the outer coil windings.

6. The device of claim 1 wherein said central and outer magnet heights are substantially equal, said outer magnet cross-sectional width is greater than or equal to said central magnet radius, said inner and outer spacer heights are substantially equal, said inner coil height is no less than said spacer height and no greater than the sum of said spacer height and one half of said magnet heights, and an air gap spacing between said magnet and coil array assemblies is at least 0.002 inches and no greater than 0.020 inches.

7. A regenerative electromagnetic shock absorber comprising:

a linear electromagnetic generator comprised of

a central magnet array assembly comprising

a central magnet array comprised of a plurality of axially-aligned, stacked cylindrical magnets having like magnetic poles facing one another,

a plurality of high magnetic permeability, high saturation magnetization, central cylindrical spacers positioned at each end of said stacked central magnet array and between adjacent stacked central magnets, and

a magnet array support for mounting said magnets and said spacers;

an inner coil array comprising a plurality of concentric cylindrical coil windings positioned adjacent to said central spacers and said magnetic poles of said central magnets, said inner coil windings surrounding an outside perimeter of said central spacers, said inner coil array mounted on a movable coil support, said movable coil support providing for reciprocating linear motion of said coil array relative to said magnet array; and

an outer magnet array assembly comprising

an outer magnet array comprised of a plurality of axially-aligned, stacked concentric toroidal magnets having like magnetic poles facing each other, said outer magnet array surrounding said inner coil array, said stacked outer concentric magnets being aligned and positioned essentially coplanar with said stacked central cylindrical magnets with the magnetic poles of said outer magnets aligned with and facing opposing magnetic poles of said central cylindrical magnets, and

a plurality of high permeability, high saturation magnetization, outer concentric toroidal spacers positioned at each end of said stacked outer magnet array and between adjacent stacked outer magnets,

said outer magnet array assembly attached to said magnet array support;

wherein a predetermined location, configuration and orientation of said central magnet magnetic poles, said central spacers, said inner coil windings, said outer magnet magnetic poles and said outer spacers provide for superposition of a radial component of a magnetic flux density from a plurality of central and outer magnets to produce a maximum average radial magnetic flux density in the inner coil windings; and

a voltage conditioning circuit electrically connected to said coil windings, said voltage conditioning circuit providing an output voltage and output current to an electrical load.

8. The regenerative electromagnetic shock absorber of claim 7 wherein said voltage conditioning circuit comprises a ferrite core transformer, a full wave rectifier bridge, a capacitor and a Zener diode.

9. The regenerative electromagnetic shock absorber of claim 7 further comprising a damping circuit electrically connected in series between said generator coil windings and said voltage conditioning circuit wherein said damping circuit is selected from the group consisting of a shunt, a multi-tap transformer having a plurality of selectable primary and a secondary winding turn ratios, and a selectable resistance array comprising a plurality of fixed resistors connected in series and parallel by way of selectable resistance switches, wherein said damping circuit controls displacement motion and displacement velocity of a movable mass.

10. The regenerative electromagnetic shock absorber of claim 9 wherein said damping circuit further comprises a monitoring circuit for measuring changes in said generator coil current or voltage output and a control circuit for dynamically adjusting a load impedance by electrically engaging said shunt, said multi-tap transformer or said selectable resistance array in response to changes in said coil output.

11. The regenerative electromagnetic shock absorber of claim 7 wherein the resultant average radial magnetic flux density in each inner coil produced by the superposition of a plurality of magnetic fields is approximately four times the average radial flux density produced in each coil by each individual magnet and wherein movement of each coil relative to said inner and outer magnet arrays generates approximately sixteen times the electrical power produced by the movement of each coil relative to each magnet.

12. The regenerative electromagnetic shock absorber of claim 7 wherein said central and outer magnets comprise magnetic materials selected from the group consisting of iron, neodymium, boron, samarium, strontium, cobalt, nickel, aluminum and their alloys, said inner and outer spacers comprise a ferromagnetic materials selected from the group consisting of iron, nickel, cobalt and their alloys, and said inner coils comprise insulated copper wire windings.

13. The regenerative electromagnetic shock absorber of claim 7 further comprising an array of outer concentric cylindrical coil windings positioned adjacent to said outer spacers, said outer coil winding height and width being substantially equal to said inner coil winding height and width, said outer coil windings surrounding an external perimeter of said outer spacers, said outer coil array mounted on said movable coil support, wherein a predetermined location, configuration and orientation of said outer magnet magnetic poles, said outer spacers and said outer coil windings provide for superposition of a radial component of a magnetic flux density from a plurality of outer magnets to produce a maximum average radial magnetic flux density in the outer coil windings.

14. The regenerative electromagnetic shock absorber of claim 7 wherein said central and outer magnet heights are substantially equal, said outer magnet cross-sectional width is greater than or equal to said central magnet radius, said inner and outer spacer heights are substantially equal, said inner coil height is no less than said spacer height and no greater than the sum of said spacer height and one half of said magnet heights, and an air gap spacing between said magnet and coil array assemblies is at least 0.002 inches and no greater than 0.020 inches.

15. A regenerative electromagnetic shock absorber system comprising:

a plurality of electromagnetic generators comprised of

a central magnet array assembly comprising

a central magnet array comprised of a plurality of axially-aligned, stacked cylindrical magnets having like magnetic poles facing one another,

a plurality of high magnetic permeability, high saturation magnetization, central cylindrical spacers positioned at each end of said stacked central magnet array and between adjacent stacked central magnets, and

a magnet array support for mounting said magnets and said spacers;

an inner coil array comprising of a plurality of concentric cylindrical coil windings positioned adjacent to said central spacers and said magnetic poles of said central magnets, said inner coil windings surrounding an outside perimeter of said central spacers, said inner coil array mounted on a movable coil support, said movable coil support providing for reciprocating linear motion of said coil array relative to said magnet array; and

an outer magnet array assembly comprising

an outer magnet array comprised of a plurality of axially-aligned, stacked concentric toroidal magnets having like magnetic poles facing each other, said outer magnet array surrounding said inner coil array, said stacked outer concentric magnets being aligned and positioned substantially coplanar with said stacked central cylindrical magnets with the magnetic poles of said outer magnets aligned with and facing opposing magnetic poles of said central cylindrical magnets, and

a plurality of high permeability, high saturation magnetization, outer concentric toroidal spacers positioned at each end of said stacked outer magnet array and between adjacent stacked outer magnets,

said outer magnet array assembly attached to said magnet array support;

wherein a predetermined location, configuration and orientation of said central magnet magnetic poles, said central spacers, said inner coil windings, said outer magnet magnetic poles and said outer spacers provide for superposition of a radial component of a magnetic flux density from a plurality of central and outer magnets to produce a maximum average radial magnetic flux density in the inner coil windings; and

a plurality of voltage conditioning circuits, each voltage conditioning circuit paired with one generator and electrically connected to said generator coil windings, said voltage conditioning circuits providing an output voltage and output current to an electrical load.

16. The regenerative shock absorber system of claim 15 further comprising a plurality of damping circuits electrically connected in series between said generator coil windings and said voltage conditioning circuits wherein said damping circuit is selected from the group consisting of a shunt, a multi-tap transformer having a plurality of selectable primary and a secondary winding turn ratios, and a selectable resistance array comprising a plurality of fixed resistors connected in series and parallel by way of selectable resistance switches, wherein said damping circuit controls displacement motion and displacement velocity of a movable mass.

17. The regenerative shock absorber system of claim 16 wherein said damping circuits further comprise a monitoring circuit for measuring changes in said generator coil current or voltage output and a control circuit for dynamically adjusting a load impedance by electrically engaging said shunt, said multi-tap transformer or said selectable resistance array in response to changes in said coil output.

18. The regenerative shock absorber system of claim 15 wherein said voltage conditioning circuits comprise a ferrite core transformer, a full wave rectifier bridge, a capacitor and a Zener diode.

19. The regenerative shock absorber system of claim 15 wherein the electrical output from each of said voltage conditioning circuits is combined with the electrical output from all of said voltage condition circuits.

20. The regenerative shock absorber system of claim 19 wherein the electrical output from each of said voltage conditioning circuits is combined in series, parallel, or a combination of series and parallel connections to produce a predetermined voltage and current for an electrical load.

21. The regenerative shock absorber system of claim 15 wherein the resultant average radial magnetic flux density in each inner coil produced by the superposition of a plurality of magnetic fields is approximately four times the average radial flux density produced in each coil by each individual magnet and wherein movement of each coil relative to said inner and outer magnet arrays generates approximately sixteen times the electrical power produced by the movement of each coil relative to each magnet.

22. The regenerative shock absorber system of claim 15 wherein said central and outer magnets comprise magnetic materials selected from the group consisting of iron, neodymium, boron, samarium, strontium, cobalt, nickel, aluminum and their alloys, said inner and outer spacers comprise a ferromagnetic material selected from the group consisting of iron, nickel, cobalt and their alloys, and said inner coils comprise insulated copper wire windings.

23. The regenerative shock absorber system of claim 15 wherein said central and outer magnet heights are substantially equal, said outer magnet cross-sectional width is substantially equal to said central magnet radius, said inner and outer spacer heights are substantially equal, said inner coil height is no less than said spacer height and no greater than the sum of said spacer height and one half of said magnet heights, and an air gap spacing between said magnet and coil array assemblies is at least 0.002 inches and no greater than 0.020 inches.

24. The regenerative shock absorber system of claim 15 further comprising an array of outer concentric cylindrical coil windings positioned adjacent to said outer spacers in said generator, said outer coil winding height and width being substantially equal to said inner coil winding height and width, said outer coil windings surrounding an external perimeter of said outer spacers, said outer coil array mounted on said movable coil support, wherein a predetermined location, configuration and orientation of said outer magnet magnetic poles, said outer spacers and said outer coil windings provide for superposition of a radial component of a magnetic flux density from a plurality of outer magnets to produce a maximum average radial magnetic flux density in the outer coil windings.