The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 03, 1997
Filed:
Oct. 17, 1994
Shogo Nasu, Kobe, JP;
Hiroshi Ryonai, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A magnetic head is provided with a protective film of chromium nitride on its sliding surface. The film thickness is set to have no adverse effect upon the electromagnetic conversion characteristics of the head, and the film has sufficient wear resistance not only against a magnetic tape having its sliding surface formed of iron oxide or other metallic magnetic substances, but also against a magnetic tape having its sliding surface formed of chrome oxide, the chrome oxide substance having a strong abrasion effect upon the magnetic head. The protective film has a compressive internal stress in a range of 10.sup.9 to 10.sup.11 dynes/cm.sup.2, a Knoop hardness of not less than 1500 kgf/mm.sup.2, a nitrogen composition ratio in a range of 20 to 60 atom %. The magnetic head core portion (23, 60) or non-magnetosensitive portion (25; 26, 61) has a plurality of minute projections (62) formed on the top surface thereof. The height of each projection is approximately equal to the size of each crystalline particle in diameter of the core portion or the non-magnetosensitive portion, where the maximum surface roughness is made greater than 150 .ANG..