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).
Collection of press clippings about the development and application of the 'Servais Silencer'.
| Identifier | ExFiles\Box 152\3\ scan0217 | |
| Date | 13th June 1937 | |
| Top left clipping: Modern Transport. June 13. Silencing of Motor Vehicles. An invention which, it is claimed, will revolutionise the silencing, not only of motor vehicles, but also of aeroplanes, machine guns and submarines, was demonstrated this week in London. Known as the Servais Silencer, and manufactured by Servais Services, Limited, of 8, Old Pye Street, Westminster, S.W.1, the apparatus can be attached to the exhaust pipe of a motor vehicle so as to render the exhaust almost inaudible. During the demonstration it was used on an engine having a penetrating exhaust note, with satisfactory effect. It is already in use on public vehicles, including motor sweepers used by the City of Westminster. The principle of the silencer is absorption of sound frequencies over any desired range, and thus it is adaptable to a large variety of purposes. Daimler to Produce Trolleybuses. We have been informed by the Daimler Co., Limited, that they will very shortly place on the market electric trolleybuses of both the four- and six-wheeled types. Mr. F. {Mr Friese} A. {Mr Adams} Garrett, M.I.A.E., has been appointed to act in a consulta- Center article: 13 JUN 1937 Motor Transport. J.13. 2 TOWARDS REDUCING NOISE Effective New Silencer A new design of exhaust silencer for which important claims are made was demonstrated in London on Wednesday. The Servais silencer, as it is called, is already installed on a number of street sweeping machines employed by the City of Westminster so as not to disturb sleeping residents when the machines are working at night, and Motor Transport was informed that the Associated Equipment Co., Ltd., is submitting the Servais silencer to stringent tests with a view to fitting it to diesel-engined buses. It is claimed that the fitting of the Servais silencer not only reduces exhaust noise, but, as compared with the normal type of silencer, also reduces fuel consumption and carbon deposit, increases engine efficiency and results in cooler running. The design of the Servais unit, which occupies no more space than the usual silencer, is based upon scientific principles, the aim being to absorb sound frequencies over any desired range. Around a completely free central exhaust passage is packed a special porous filling built up of constantly varying cells, which are free to vibrate within the outer casing. In this way the sound vibrations of the exhaust are absorbed. The instrument is also being employed to silence machine guns, and the Admiralty is understood to be experimenting with the device for silencing the diesel engines of submarines. It is an entirely British production handled by Servais Services, Ltd., 8, Old Pye Street, London, S.W.1. Top right clipping: Servais S DURRANT'S PRESS CUTTINGS St. {Capt. P. R. Strong} Andrew's House, 32 to 34 Holborn Viaduct, and 3 St. {Capt. P. R. Strong} Andrew Street, Holborn Circus, E.C.1. Telephone: CENTRAL 3149 (Two Lines). Gloucestershire Echo 1 Clarence Parade, Cheltenham. Cutting from issue dated..11. June....1936 NOISELESS STREET SWEEPERS ONE of the latest aspects of London's anti-noise campaign is the adoption by Westminster City Council of a fleet of silent street sweepers. The engines of these vehicles, which operate by night, are specially silenced by the employment of a new British invention, and the sweepers glide about with a wraith-like absence of sound. The silencer itself, incidentally, is capable of adaptation to many uses, some of which were demonstrated to me in London to-day by representatives of the inventor. Among other things, a small version of the device will render inaudible at a few yards range the report of a pistol being fired! FOR AEROPLANES, TOO THE fact that the device can be used for silencing of internal combustion engines without appreciable loss of power gives it added significance from the point of view of aircraft use. Moreover, it has actually been shown to improve the running of an engine and to conserve petrol—both points of great importance. One type of the device can be used for the silencing of machine guns, whose vulnerability in the past has been their noise. Bottom right clipping: Servais S. DURRANT'S PRESS CUTTING St. {Capt. P. R. Strong} Andrew's House, 32 to 34 Holborn Viaduct, and 3 St. {Capt. P. R. Strong} Andrew Street, Holborn Circus, E.C.1. Telephone: CENTRAL 3149 (Two Lines). Edinburgh Evening News 18 Market Street, Edinburgh. Cutting from issue dated..17.June...1936 | ||