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:
May. 24, 1994
Filed:
Jun. 21, 1991
Rembert R Stokes, Inverness, IL (US);
Anand K Upadhyay, Libertyville, IL (US);
Motorola Lighting, Inc., Buffalo Grove, IL (US);
Abstract
A transformer (202) has a bobbin (2) which has an inner portion (104) supporting an inner electrical winding (140) and having a magnetic core recess. The inner portion is located within an outer portion (4) supporting an outer electrical winding (40). The inner portion further has an end with a termination connected to the inner winding, an annular recess (126) in which the inner winding is situated, and a channel (132) communicating between the termination end of the inner portion and a remote end of the annular recess. The channel is positioned radially inwardly of the first annular recess and accommodates a portion of the inner winding. By providing the channel radially inwardly of the annular recess, winding wire can extend between the termination end of the inner portion and the remote end of the annular recess across the annular recess without significantly increasing the size of the inner portion and without increasing the gap between the inner and outer portions. This allows the size, weight and cost of a transformer built with the bobbin to be reduced, and improves the transformer's magnetic performance. The channel also allows layered windings terminating at the same end of the inner portion to be formed from an odd number of winding passes, reducing corona voltage breakdown effect and so prolonging the practical life of the windings. This also allows the inner portion to be wound uninterruptedly by machine without manual intervention.