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).
Springing demonstration to diagnose a suspension complaint in the Phantom model.
| Identifier | WestWitteringFiles\O\January1926-March1926\ Scan168 | |
| Date | 26th March 1926 | |
| TO R.{Sir Henry Royce} FROM DA.{Bernard Day - Chassis Design} C. to CJ. GWB. HS.{Lord Ernest Hives - Chair} EP.{G. Eric Platford - Chief Quality Engineer} E.{Mr Elliott - Chief Engineer} ORIGINAL DA{Bernard Day - Chassis Design}1/M26.3.26. PHANTOM SUSPENSION. X8440 X8520 X2628 In accordance with your instructions Mr. Hardy and I went to Derby and attended a springing demonstration, the object of which was to arrive at an exact definition of the suspension feature now being complained of. CWB, HS{Lord Ernest Hives - Chair} and EP.{G. Eric Platford - Chief Quality Engineer} were present and the springing feature demonstrated was appreciated by all, and agreed to by CWB. as being that of which Sales are complaining. This feature may be described as a series of oscillations of small amplitude felt by the passenger as a series of jolts, occurring at speeds from 20. to 25 MPH. The periodicity of the oscillation is rather higher than that of the chassis on the road springs, but not so high as that of the axles on the tyres. It did not appear to be quite regular but seemed to average from 160 to 200 per minute. The jolts are not severe but are tiring by their persistence, continuing as they did in most of the combinations demonstrated, the whole time the car was on that particular stretch of road. They are much more noticeable in the rear than in the front seats. This road is the London road just beyond Alvaston, and would undoubtedly be called a good road. In parts there are a series of small and fine pitched ripples, and all along its length occasional bumps and depressions, about .250 from crest to bottom, but the surface as a whole was reasonably smooth tar macadam, quite free from potholes, large corrugations, etc. It was demonstrated and agreed to by all that:- (1) An EAC.3. Silver Ghost trials landaulet with four wheel brakes and high pressure tyres (40/45 lbs. per sq. in.) and shock dampers set to standard loads, springs to standard schedule, with six passengers, had the complaint quite badly, though it had been used as a trials car without criticism of this point for some time. (2) By reducing the front shock damper load the complaint was reduced appreciably. (3) By taking a New PhantomCodename for PHANTOM I saloon with high pressure tyres (40/45 lbs. per sq. in.) and springing to schedule, well greasing the springs and removing shock dampers front and rear the complaint could be reduced so as to be practically negligible. One noticeable thing was that such jolts as did occur were not persistent, but there were periods of complete rest. (4) By coupling up the front shock absorbers only, the complained of feature returned. (5) Coupling up the rear shock dampers in addition increased the complaint, being now about the same as (1). (1) | ||