IP Library Granted Patent US 8,986,568
Granted Patent B2
US 8,986,568 · App. 13/637,559 · Granted Mar 24, 2015

Sintered magnet and method for producing the sintered magnet

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Quick Facts
Patent No.
US 8,986,568
App. No.
13/637,559
Granted
Mar 24, 2015
Kind
B2
Abstract

The present invention aims to ensure strength of a thin-walled sintered magnet. A sintered magnet is a ferrite sintered magnet made by sintering a magnetic material. A magnetic powder mixture obtained by mixing magnetic powder with a binder resin is injection-molded into a mold with a magnetic field applied thereto to produce a molded body, which is then sintered to produce the sintered magnet. The sintered magnet has a thickness of 3.5 mm or less in the position of center of gravity thereof. The sintered magnet has a surface roughness Rz of 0.1 μm or more and 2.5 μm or less. The surface roughness Rz is a 10 point average roughness.

Claims (2)

1. A sintered magnet made by sintering a magnetic material, the sintered magnet having a thickness of 3.5 mm or less in the position of center of gravity thereof and a surface roughness Rz of 2.5 μm or less, And the sintered magnet is a hard ferrite sintered magnet.

2. The sintered magnet according to claim 1 , wherein the surface roughness Rz is 0.1 μm or more.

Assignments (3)
CHANGE OF ADDRESS Recorded Jun 12, 2013
From: TDK CORPORATION
To: TDK CORPORATION
Reel/Frame 030651/0687 →
RECORD TO CORRECT 2ND & 6TH ASSIGNOR EXECUTION DATES ON AN ASSIGNMENT DOCUMENT PREVIOUSLY RECORDED ON 09/26/2012, REEL 029067/FRAME 0043. Recorded Oct 17, 2012
From: MORITA, HIROYUKI; MINACHI, YOSHIHIKO; MORI, TAKAHIRO; KATO, TATSUYA; SUTO, NOBUHIRO; OJI, NAOTO
To: TDK CORPORATION
Reel/Frame 029149/0143 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 26, 2012
From: MORITA, HIROYUKI; MINACHI, YOSHIHIKO; MORI, TAKAHIRO; KATO, TATSUYA; SUTO, NOBUHIRO; OJI, NAOTO
To: TDK CORPORATION
Reel/Frame 029067/0043 →