Spark, Bownian, Warrior, Torpedo... who made the frames?

[cardan]

... and the Villiers "invention" looks exactly like the equivalent part of the Lucas Magdyno! One of the claims even covers that the drive gear F is made from fibre!!!! Perhaps patent assessment wasn't at its best between Nov 1943 (first application) and Oct 1945 (granted).

G.B. was getting fabulous four-stroke twins from JAP - not sure why he would want to evaluate an unproven four stroke twin from Villiers? I like the idea that he was evaluating a two-stroke twin, but it's just my fantasy. Surely someone knows about the Brough Superior Villiers? No mention in Rolls Royce of Motorcycles.

Leon

[Edit: Sorry, I see what you're saying - I didn't mean that the slip drive was innovative, rather that the mounting of the generator in front of the cylinder may have been innovative in 1945. I think the Speed Twin used a magdyno prewar? By the way, Edward Turner did file a patent in 1938 for the drive of the camshaft and magneto in the Speed Twin, but it was a bit weird, using the half time pinion to drive an internally cut gear on the inside of the lowest sprocket, which drove the cam and then magneto buy chain. I don't think that idea made it to production? I know little about Triumph twins...]

[R]

We wonder if Lucas paid Villiers a licence/patent fee  ??
The sort of stuff we might not hear about.

A lot of auto makers shell out for all sorts of bits and ideas in cars.
A few cents here and there, but it all adds up.

One of the big agricultural firms paid out, a fair bit, when it turned out their contra-rotating seeding device was already patented.
Ignorance is no excuse for not paying ....
And while the patent is in force, regardless.

[john.k]

The slipping gear with a star shaped spring was on Magdyno s long before WW2......Id think Villiers claim was to do with mounting it on the camshaft ..........which is just plain dumb ,as a slipping drive would need the whole timing case dismantled ,just to replace the spring .........the Lucas spring was also adjustable ...In fact ,I see nothing of value in any of those patents..........Anyhoo,my favourite would be the Walter Moore patent of the pivoted gearbox mounting ........BSA refused to pay ,and went to great lengths to avoid the patent by all kinds of workarounds.

[R]

Nortons early dommie twins had the fibre gear thusly mounted on the camshaft.
If anything goes wrong in the drive dept, the timing cover has to come off.
If anything goes wrong with the fibre gear, the debris goes into the engine oil !!
In spite of which, it does work reasonably well.
(I always wonder if the genny is actually spinning )

And, the fibre gear is fractionally different (but almost identical) to the magdyno one.
Woe betide anyone who uses the wrong one, the tooth count (form ?) is not quite the same. ?
Dunno who's genius idea that one was ??

[john.k]

The slipping drive on the magdyno was claimed to protect the against a violent backfire .....generally restricted to sporty singles ........twins didnt have this problem .........the fibre gear was to reduce gear noise .......most twins had fibre mag drive gears ...........Incidentally,its not generally realized the fibre was very expensive ,and a steel or iron gear would be much cheaper .............i have a sheet of the fibre about 1m square X 1/2" thick  ,that cost over $1000 ...(its a compressed and vulcanized bakelite resin and cloth material ...and some variations have the property of running heavily loaded lubricated only by water ....steel mill rolls.......its also use in ship stern tubes with alternating rubber and fibre strips which run in sea water.)