Rolls-Royce Archives
         « Prev  Box Series  Next »        

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).
The design and manufacturing process for rubber-mounted fan blades.

Identifier  ExFiles\Box 135\4\  scan0053
Date  14th March 1940
  
Jnr.{Charles L. Jenner}
c to Rm.{William Robotham - Chief Engineer}
c to Rm{William Robotham - Chief Engineer}/Col.

Rm{William Robotham - Chief Engineer}/Ed.{J. L. Edwards}3/GH.14.3.40.

re RUBBER MOUNTED FAN BLADES.

In reply to your Jnr.{Charles L. Jenner}1/JH.6.3.40., we have gone over the print PL.143 and quite agree that the job appears to have become considerably more complicated than we expected. Going over your three points, one at a time we should like to make the following comments:-

1. We agree that it would be very nice that the five blades should all rotate by the same amount, but in connection with this it must be borne in mind that our idea for production on this fan was to make all the parts from pressings. This would of course mean that blades would come out identical and the only variable factor affecting rotation would be the hardness of the rubber.

2. We are in complete agreement that the rubber mounting should be called upon to work in a twisting plane, but we favour your original idea of building the fan up with a central spider only, rather than make the flange piece from a machined casing which it appears would be necessary. This spider would of course considerably assist the elimination of the cantilever load on the rubber, mentioned in point 3.

As you will recall our original conception of this job was fan blades made up by copper brazing two pressings together, these giving us very simply the cylindrical part required at the root of the blade, and would also provide a rough hole which would only need reaming of at the most rough boring and reaming to make it suitable for the central spider. The outer flange could be made up from two similar pressings held together by spot welding before vulcanising and this could also be arranged to provide the bolt fixing for the fan.

- continued -
  
  


Copyright Sustain 2025, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙