Ignition coil patents of interest: trimmers, chainsaws , lawnmowers

[motoman]

First an explanation to Bert . I had promised a PM , but the patents may be of interest to other forum visitors. There are many problems in the forum concerning "no spark" and what to do. The patent articles are very technical, but the summaries are in English and worth reading. These coils have been constantly improved. Among the benefits to readers will be how complex these modules are and so can not be easily tested. Next , to me , great insight into timing which some readers have questioned, Type in a search word "US" followed by the 7 digits. Do not "turn off" due to the schematics, etc.

US 5295465 (Kohler 1994))
US 3484677A (Magnetron) 1969
US 6388445 (Walbro timing)
US 4817577 (Briggs 1988))
US 8807119 (Ti Gp 2014 timng and anti- kickback)
US 5058543A (Stens 1991)
US 3894525 (Bosch "thick film" chip)

EP 1691053B1 (Walbro)

 

[bertsmobile1]

First an explanation to Bert . I had promised a PM , but the patents may be of interest to other forum visitors. There are many problems in the forum concerning "no spark" and what to do. The patent articles are very technical, but the summaries are in English and worth reading. These coils have been constantly improved. Among the benefits to readers will be how complex these modules are and so can not be easily tested. Next , to me , great insight into timing which some readers have questioned, Type in a search word "US" followed by the 7 digits. Do not "turn off" due to the schematics, etc.

US 5295465 (Kohler 1994))
US 3484677A (Magnetron) 1969
US 6388445 (Walbro timing)
US 4817577 (Briggs 1988))
US 8807119 (Ti Gp 2014 timng and anti- kickback)
US 5058543A (Stens 1991)
US 3894525 (Bosch "thick film" chip)

EP 1691053B1 (Walbro)

Thanks a good read.
I realise these are USA specific.
However that all go back to the Atom ignition of 1966
Good point about testing I go blue in the face trying to make people understand you can not check them with a simple ohm meter reading and to all extents & purpose the only test is substitution with a know good one.

 

[motoman]

I saw over 30 patents and references. The oldest in the 1890's and ... (drumroll) ...Tesla's name again. Also activity in the 1930's. Looks like the Germans were leaders. What a surprise.:laughing:

Edit: If readers choose only one take a look at the 2014 Ti Gp patent with the anti kick-back feature. The module can sense where the piston is and which direction,