Low-noise magnetic read/write head

Patent 4939608 Issued on July 3, 1990. Estimated Expiration Date:

December 21, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

Single-track video ferrite record/reproduce head and manufacturing method therefor
Patent #: 4017899
Issued on: 04/12/1977
Inventor: Bagby

Combination magnetic head Patent #: 4531170
Issued on: 07/23/1985
Inventor: Takei , et al.

Inventors

Application

No. 289401 filed on 12/21/1988

US Classes:

360/121, Plural gaps360/122, Head surface structure360/125Head core

Examiners

Primary: Tupper, Robert S.

Attorney, Agent or Firm

Finnegan, Henderson, Farabow, Garrett and Dunner

Foreign Patent References

54-106051 JP 04/22/1981

International Classes

G11B 005/265
G11B 005/187

Foreign Application Priority Data

1985-11-30 JP

Abstract

Disclosed is a magnetic head apparatus, which comprises a pair of magnetic cores defining a magnetic gap for recording and reproducing information, and grooves in the lateral faces of the magnetic cores, extending at right angles to those faces of the cores which are opposed to a magnetic recording medium or which define the magnetic cores. The grooves determine the width of the magnetic gap. That face of at least one of the magnetic cores which is opposed to the recording medium, is recessed from the remaining portion of the core, so as to cover a width equivalent to the length of the grooves, at the maximum. In the magnetic head of the invention, moreover, a nonmagnetic portion is formed at least on an erase gap, so that the degree of magnetic coupling between the erase gap and the recording medium is lower than that between a read/write gap and the medium. Thus, magnetic induction, which is produced in the erase core when data is read from the medium, is reduced.