| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United States | 5 | |
| #2 | Germany | 2 | |
| #3 | Japan | 2 | |
| #4 | Canada | 1 | |
| #5 | Spain | 1 | |
| #6 | Finland | 1 | |
| #7 | France | 1 | |
| #8 | Italy | 1 | |
| #9 | Netherlands | 1 |
| # | Industry | |
|---|---|---|
| #1 | Electrical machinery and energy |
| # | Technology | |
|---|---|---|
| #1 | Spark gaps and corona devices |
| # | Name | Total Patents |
|---|---|---|
| #1 | Wax Bernard | 9 |
| #2 | Baanaado Watsukusu | 2 |
| Publication | Filing date | Title |
|---|---|---|
| US4206381A | Lean burn spark plug | |
| US4272697A | Spark plug with annular rings in insulating core channels forming series gap | |
| US4081711A | Spark plug | |
| ES433717A1 | Improvements in ignition plugs. (Machine-translation by Google Translate, not legally binding) | |
| NL7500341A | Spark plug with insulation covered electrode points - insulation reduces chemical and electrical erosion | |
| IT1026068B | Spark plug with insulation covered electrode points - insulation reduces chemical and electrical erosion | |
| DE2457955A1 | Spark plug with insulation covered electrode points - insulation reduces chemical and electrical erosion | |
| CA1035648A | Spark plug | |
| US3921020A | Spark plug | |
| US3872338A | Spark plug |