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).
Design, advantages, and drawbacks of a Bensport shoe-type servo system.
| Identifier | ExFiles\Box 87\5\ scan0004 | |
| Date | 30th November 1932 | |
| X2H.1. BY.{R.W. Bailey - Chief Engineer} FROM DA.{Bernard Day - Chassis Design} DA{Bernard Day - Chassis Design}1/M30.11.32. C. to SG.{Arthur F. Sidgreaves - MD} WOR.{Arthur Wormald - General Works Manager} HS.{Lord Ernest Hives - Chair} E.{Mr Elliott - Chief Engineer} BENSPORT SERVO. Herewith we send N.sch. 3610. shewing the shoe type servo for the above chassis, giving the increased torque with reduced surface pressures and end loads. It is appreciated that the wrapping feature inherent in this type of servo is not an advantage because of its tendency to inconsistency, but it is thought that the low co-efficient of friction we are counting on the wrapping will not be a very disturbing feature. The other advantages of this type of servo are an increased mean radius of action of the friction surfaces, and the superior cooling. R.{Sir Henry Royce} has suggested that we can eliminate one of of the rods between the servo and the balancing lever by picking up the driven scissors lever by means of jaws or pins on the servo. This is the arrangement shewn in the main scheme, but we appreciate that there is a drawback in that the scissors lever has to slide axially under the heavy load of this pick up, thus introducing friction which has to be supplied by the pedal. In view of this possible objection we have shewn an alternative arrangement of the brake carrier so that a three-rod connection to the balancer lever can be used if found desirable. DA.{Bernard Day - Chassis Design} | ||