Development of the Lead-Free Brush Material for the High-Load Starter

Ryoichi HONBO
Youichi MURAKAMI
Koichiro SAWA
Hiroyuki WAKABAYASHI
Naruhiko INAYOSHI
Kyoji INUKAI
Takeshi SHIMOYAMA
Naoki MORITA

Publication
IEICE TRANSACTIONS on Electronics   Vol.E90-C    No.8    pp.1634-1642
Publication Date: 2007/08/01
Online ISSN: 1745-1353
DOI: 10.1093/ietele/e90-c.8.1634
Print ISSN: 0916-8516
Type of Manuscript: PAPER
Category: Electromechanical Devices and Components
Keyword: 
carbon brush,  starter,  lead,  wear,  tribology,  

Full Text: PDF>>
Buy this Article



Summary: 
This paper reports the development of a lead-free brush material for a high-load starter. These brushes are used in much more extreme conditions -- at the PV-value (the product of brush contact pressure and sliding velocity) approximately three times that of other starter brushes, and double the electrical current density. The major technical requirement of this development was to decrease the electrical wear in brushes caused by commutation sparking. We developed a brush material that reduces electrical wear by adding zinc phosphate. Because zinc phosphate can improve the lubricity at high-temperature and the contact stability of brushes, the developed brush reduces commutation sparks. The life of the developed brush is about 1.5 times longer than that of conventional brushes containing lead.