US 7,583,171 B2 · Magnetic field generator, photomagnetic information storing system, and photomagnetic information storing apparatus

Abstract

The present invention efficiently radiates heat generated by a coil while suppressing a decrease in the efficiency of generation of magnetic fields caused by an eddy current. The present invention includes a coil extending spirally in a plane and covered with a dielectric material, a magnetic substance provided parallel with the plane so as to overlap the coil, and a radiator extending in the plane so as to surround the coil and having projecting portions which project toward an outermost periphery of the coil and groove portions recessed in a direction opposite to that in which the projecting portions project, the projecting portions and the groove portions being alternately arranged, the radiator having a higher thermal conductivity than the magnetic substance.

Claims5

Dependent claims

A magnetic field generator comprising:

a coil extending spirally in a plane and covered with a dielectric material;
a magnetic substance provided parallel with the plane so as to overlap the coil;
and
a radiator extending in the plane so as to surround the coil and having projecting portions which project to an outermost periphery of the coil and groove portions which are recessed in a direction opposite to the direction in which the projecting portions project, the projecting portions and the groove portions being alternately arranged, the radiator having a higher thermal conductivity than the magnetic substance, and
wherein the magnetic substance extends parallel with the plane to a corresponding position between the projecting portions while avoiding overlapping the projecting portions.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application

11/082,173Filed 16 Mar 2005 · continuation

Priority

25 Apr 2003

Published

US 2005/0157596 A121 Jul 2005

Granted

1 Sep 2009

Term ends

Not estimatedThe source records don’t support an estimate.

Classification6 codes

G11B 11/10534
Heads: for recording by magnetising, demagnetising or transfer of magnetisation, by radiation, e.g. for thermomagnetic recording
G11B 33/1406
Reducing influence of physical parameters, e.g. temperature change, moisture, dust: reducing the influence of the temperature
G11B 11/10554
Arrangements of transducers relative to each other, e.g. coupled heads, optical and magnetic head on the same base: the transducers being disposed…
G11B 17/30
From random access magazine of disc records: wherein the playing unit is moved according to the location of the selected record

Magnetic field generator, photomagnetic information storing system, and photomagnetic information storing apparatus

Life of this patent

Magnetic field generator, photomagnetic information storing system, and photomagnetic information storing apparatus

Life of this patent

Abstract

Claims5