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From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Comparing an Isotta Fraschini car to a company model and discussing similarities in gearbox designs.

Identifier  ExFiles\Box 22\2\  Scan050
Date  1st January 1930
  
X4609

E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} ) FROM R
HS.{Lord Ernest Hives - Chair} ) (At Le CanadelHenry Royce's French residence)
c. Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} Bv.
c. Mr.Claremont.

R1/M.1.30.

X.4609
X.523
X.4510

CAR AND AERO WORK
CHANGE SPEED GEAR

Mr.Salerni visited Le CanadelHenry Royce's French residence yesterday. He came on an Isotta Fraschini, comparable for size to our 40/50. It has 8 cyls. and the engine did not seem bad except that he did not make it do any slow pulling on top gear - (I believe that this is how others with large "sixes" get out of torque reactions).

The suspension was terribly harsh and rough, the gearbox was definitely bad, and he said that the brakes were very poor. The car was 2 years old, but represented the present model I understand. It had not done so many miles as 18-EX.

The Isotta Fraschini is the grandest of the Italian cars, but I should call it an absolute failure as a carriage. Mr.Salerni said our car was a revelation to him on these roads.

Since I have been here he has sent me a blueprint of his gear-box with epicyclic gears, somewhat of a staggerer to me as it is exactly the gear we schemed for 2 speed Blower drive on the small private aero engine, arranged to give 4 speeds and reverse without any additional wheels.

Is it possible that he or his young draughtsman saw our drawing? I do not think so, but it is a wonderful coincidence, and I do not know whether our patent is before or after his.

You will remember that our scheme of gears was suggested by me coming home in the train with E.{Mr Elliott - Chief Engineer} probably nearly a year ago, and our patent was in Mr.Claremont's hands for some time, and probably delayed by my want of attention. I intended, and believe it was, covered for driving both ways as a multiplication and a reduction gear.

The application as a speed change is wonderfully compact, and very little of it. He hasarranged it with 4 baulk rings like his coupling, and it appears to get over some of the troubles with the reverse, and if it proves a good gear it may be one of the solutions of the problem.
  
  


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