Omnidirectional electromagnet

Patent metadata

Field	Value
Publication number	US-10199147-B2
Application number	US-201314436679-A
Country	US
Kind code	B2
Filing date	Oct 18, 2013
Priority date	Oct 18, 2012
Publication date	Feb 5, 2019
Grant date	Feb 5, 2019

Abstract

An omnidirectional electromagnet (100) is disclosed. The omnidirectional electromagnet (100) comprises a ferromagnetic core (110) and three orthogonal solenoids (120, 130, 140) disposed about the core (110). Each solenoid (120, 130, 140) is adapted to receive a current from a current source to control an orientation and a magnitude of a magnetic field generated by the omnidirectional electromagnet (100). One or more omnidirectional electromagnets (100) can be used as a single magnetic manipulation system. The magnetic field generated by the omnidirectional electromagnet system can be used to control at least one of a force, a torque, an orientation, and a position of an adjacent magnetic object.

First claim

What is claimed is:

1. An omnidirectional electromagnet, comprising:
a ferromagnetic core which is configured as a spheroid; and
three orthogonal solenoids disposed about the core, each solenoid adapted to receive a current from a current source to control an orientation and a magnitude of a magnetic field generated by the omnidirectional electromagnet, wherein a variance between dipole moments of each solenoid is minimized when current density of each solenoid is equal, and such that a diameter of the ferromagnetic core is between 40% and 75% of a maximum outer length of an outermost solenoid of the three orthogonal solenoids.

2. The omnidirectional electromagnet of claim 1 , wherein the ferromagnetic core comprises a solid core.

3. The omnidirectional electromagnet of claim 1 , wherein the solenoids are disposed within a resin or varnish.

4. The omnidirectional electromagnet of claim 1 , wherein at least one of the three orthogonal solenoids is configured as a cuboid sleeve.

5. The omnidirectional electromagnet of claim 4 , wherein the three orthogonal solenoids are configured as cuboid sleeves, and a first of the three orthogonal solenoids is nested within a second of the three orthogonal solenoids, which is nested within a third of the three orthogonal solenoids.

6. The omnidirectional electromagnet of claim 1 , wherein at least two of the three orthogonal solenoids are intertwined with one another.

7. The omnidirectional electromagnet of claim 1 , further comprising a coolant disposed between at least two of the three orthogonal solenoids.

8. An omnidirectional electromagnet system, comprising:
a current source; and
an omnidirectional electromagnet electrically coupled to the current source, and having a ferromagnetic core which is configured as a spheroid, and
three orthogonal solenoids disposed about the core, each solenoid adapted to receive a current from the current source to control an orientation and a magnitude of a magnetic field generated by and adjacent to the omnidirectional electromagnet, wherein a variance between dipole moments of each solenoid is minimized when current density of each solenoid is equal, and such that a diameter of the ferromagnetic core is between 40% and 75% of a maximum outer length of an outermost solenoid of the three orthogonal solenoids.

9. The omnidirectional electromagnet system of claim 8 , further comprising a control system for controlling current to the omnidirectional electromagnet to coordinate orientation and magnitude of the magnetic field of the omnidirectional electromagnet to control at least one of a position and an orientation of an object, or to control at least one of a force and a torque applied to an object.

10. The omnidirectional electromagnet system of claim 8 , further comprising one or more additional omnidirectional electromagnets electrically coupled to the current source.

11. The omnidirectional electromagnet system of claim 10 , further comprising a control system for controlling current to the omnidirectional electromagnets to coordinate orientation and magnitude of the magnetic field of the omnidirectional electromagnets to control at least one of a position and an orientation of an object, or to control at least one of a force and a torque applied to an object.

12. A method of manipulating the object of claim 9 , comprising:
a. associating the object with the magnetic field of the omnidirectional electromagnets; and
b. adjusting an orientation and magnitude of the magnetic field in order to move the object.

13. The method of claim 12 , wherein the device is at least one of a capsule endoscope device, a magnetic catheter device, a cochlear implant, a device within an eye, a device within a urinary or reproductive system, a device within the brain or spine, and a device for medical procedures on a developing fetus.

14. The method of claim 12 , wherein the device is at least one of a microscale device under the guidance of an optical microscope, a device in outer-space, and a device within a pipe or pipe-like structure.

15. The omnidirectional electromagnet of claim 1 , wherein the diameter of the ferromagnetic core is between 55% and 65% of the maximum outer length of the outermost solenoid.

16. The omnidirectional electromagnet of claim 1 , wherein the wherein the variance in dipole moment (m) of each solenoid is zero when current density (J) of each solenoid is equal (i.e. m x =m y =m z when J x =J y =J z ).

17. The omnidirectional electromagnet of claim 1 , wherein each of the three orthogonal solenoids have square-cross-section geometries which minimize a quadrupole term in a multipole expansion for the magnetic field produced by the solenoids, where the quadrupole term is proportional to:
(15 W 2 −15 L 2 +40 T 2 +30 TW )(4 T 2 +6 TW + 3 W 2 )−16 T 4

where W is inner width, L is length, and T is thickness.

18. The omnidirectional electromagnet of claim 17 , wherein the quadrupole term is equal to zero.

Assignees

• Univ Utah Res Found

Inventors

• Petruska Andrew J
• Abbott Jacob J

Classifications

• H01F7/206 Primary

  Electromagnets for lifting, handling or transporting of magnetic pieces or material (electromagnets for guidance of vehicles, workpieces B65G21/2009; for magnetic suspension or levitation H02N15/00) · CPC title

• H01F7/20 Primary

  without armatures (cores H01F3/00; coils H01F5/00 {; shaping metal by applying magnetic forces B21D26/14; electromagnets specially adapted for NMR applications G01R33/381}) · CPC title