Joseph M Leptich

50146564, May 14, 1991

Apr 25, 1990

7/513498

Joseph M. Leptich - Grand Blanc MI
Keith A. Penney - Davison MI
Steve F. Lowe - Drayton Plains MI

General Motors Corporation - Detroit MI

H01T 1308
H01T 1332

123169EL

An internal combustion engine includes a cylinder head and a permanent ground electrode and replaceable center electrode element received in a cylinder head bore. The permanent ground electrode is affixed to the cylinder head at the inner wall thereof and protrudes into the combustion chamber. The ground electrode preferably has a cup-like configuration defining an electrode-receiving hollow in the combustion chamber in registry with the bore. The center electrode element comprises a center electrode and an insulator body having a shoulder for engaging a seat in the bore. The insulator body shoulder is clamped against the seat by an annular retainer nut. When the center electrode element is so clamped, the center electrode is received in the electrode-receiving hollow defined by the ground electrode in the combustion chamber so as to cooperate with the ground electrode in defining a spark gap therebetween.

60621850, May 16, 2000

Sep 25, 1998

9/160399

Randolph Kwok-Kin Chiu - Davison MI
Charles Dale Oakley - Davison MI
Joseph Michael Leptich - Clarkston MI
Gamdur Singh Mann - Grand Blanc MI
David Kwo-Shyong Chen - Rochester Hills MI

General Motors Corporation - Detroit MI

F02B 908
F23Q 722

123145A

A glow sensor provides functions of both a diesel engine glow plug for aiding fuel ignition during starting and low temperature operation and an ion sensor for sensing engine combustion initiation and characteristics. Compact glow sensor components may be assembled directly in combination with an engine combustion chamber defining component, such as a cylinder head, to provide a combination in which separate housings or shells for the glow sensors are not needed. Thus, the glow sensor elements and insulation may be made larger to provide greater electrical resistance in the ion sensor electrical circuit and enhance the operation of the ion sensor function. Various forms of glow sensors may optionally be used in such a combination including, for example, metal sheath type glow sensors with either isolated or non-isolated coils and ceramic rod or flat plate type glow sensors. Exemplary embodiments of glow sensor components mounted in a cylinder head are disclosed.