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:
Jan. 12, 2010
Filed:
May. 05, 2006
Jong Kwan Park, Daegu, KR;
Young Su Jeon, Daegu, KR;
Jong Kwan Park, Daegu, KR;
Young Su Jeon, Daegu, KR;
Korea Sintered Metal Co., Ltd., Daegu, KR;
Abstract
A high frequency heat treatment method for a fine bottom-closed hole includes preparing a coil so as to be completely inserted into the fine bottom-closed hole, preparing a core for controlling a magnetic flux within the coil such that the core protrudes from upper and lower sides of the coil, heat-treating a target part of the fine bottom-closed hole under conditions of a heating time of 2˜3 seconds, an output power of 200˜300 kW, a quenching time of 3˜5 seconds, a positive electrode voltage of 4 ˜8 kV, and a positive electrode current of 2.0˜4.5 A, and quenching the heat-treated part of the fine bottom-closed hole with cooling nozzles fixed around the heat-treated part such that a sufficient amount of cooling water is injected uniformly over the whole heated part with a sufficient pressure via the cooling nozzles.