Spark plug cap with ignition voltage detective capacitor for internal combustion engine
US5487676A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 1993 |
| Grant date | Jan 30, 1996 |
| Priority date | — |
| Expiry date | Nov 9, 2013 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02P2017/006
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A spark plug cap covering the terminal of a spark plug for an internal combustion engine, made up of an insulative cap body, an ignition coil unit case housing the coil and having a terminal for the ignition coil, a first conductive shaft housed in the insulative cap body for carrying an ignition voltage produced by the ignition coil to the spark plug terminal, and a second conductor located around the first conductor keeping a predetermined distance therefrom separated by the insulative material of the cap body such that a capacitor is formed between the first and second conductors for detecting the ignition voltage. The cap is further provided with a first contact in the form of an annulus provided at the end of said insulative cap body and electrically connected with said second conductor, and a second contact in the shape of a leaf spring electrically connected with the terminal of said case, such that the second contact is brought into contact with the first contact when said case is threaded into said insulative cap body, thereby ensuring electrical connection therebetween.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.