05050276 is referenced by 180 patents and cites 6 patents.

A magnetic clasp has two mirror image halves each of which is attached to the ends of a necklace. Each half has a magnetic shell and an inserted magnetic core. The shell has a cylindrical body with a cone-shaped end. The front of the shell has an open cavity for inserting the magnetic core. The front of the shell and magnetic core form a flat surface. The magnetic core is made of samarium cobalt or neodymium iron. Both are strong magnets and allow the clasp to be very small in size so that it is aesthetically pleasing and lightwise. The end of each half has an eyelet for connecting to a necklace. A conventional fastener can be soldered to one eyelet so that the clasp can be added to an existing necklace. A safety catch can be added to the clasp as a back-up safety feature for expensive jewelry.

Title
Magnetic necklace clasp
Application Number
7/537854
Publication Number
5050276
Application Date
June 13, 1990
Publication Date
September 24, 1991
Inventor
J C Pemberton
P.O. Box 20005, San Diego, 92120
CA, US
Agent
Jessup Beecher & Slehofer
IPC
A44B 21/00
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