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).
Sectional list describing the HF 'Rotoflator' (BV5), a tyre inflator for giant tyres.
| Identifier | ExFiles\Box 149\5\ scan0042 | |
| Date | 1st July 1923 | |
| PAGE 1 HF{H. W. Frost - Coachwork Inspector} Sectional List No 131 TYRE MAINTENANCE HF{H. W. Frost - Coachwork Inspector} PLANTS HF{H. W. Frost - Coachwork Inspector} “ROTOFLATOR” (BV5) for GIANT TYRES Fig. 572 HF{H. W. Frost - Coachwork Inspector} “ROTOFLATOR” BV5 GIANT TYRES are provided for by the special model “Rotoflator” known as the BV5. This is similar in design to other models, but is larger, more powerful and has the remarkable delivery of over 10,000 cubic inches of free air per minute. The appliance is designed for Belt Drive having pulleys 5¾ inches diameter for 1½ inch Belts, running at a speed of from 850/950 R.P.M. Fast and loose pulleys are supplied, not a single pulley as shown in illustration. Air delivery is direct to the tyre without the use of a storage tank and the supply can be taken through a pipe line or straight from the hose supplied with the plant. A powerful compressor is essential for inflating giant tyres and we claim for the HF{H. W. Frost - Coachwork Inspector} “Rotoflator” that it supplies this need in every particular. PRICE (subject to special discounts) Complete with Pulleys, Brackets, Air Hose, 1 Pressure Gauge and Valve Adapter £21 . 10 . 0 All goods sold Ex Works Prices subject to alteration without notice HARVEY FROST & CO. LTD 148-150 GREAT PORTLAND ST.{Capt. P. R. Strong} LONDON W.1. Telegrams HARVEYIZED WESDO LONDON Telephone LANGHAM 1343/4 5—1,250. 7/23 PAGE 2 HF{H. W. Frost - Coachwork Inspector} Sectional List No 131 TYRE MAINTENANCE HF{H. W. Frost - Coachwork Inspector} PLANTS THE HF{H. W. Frost - Coachwork Inspector} “ROTOFLATOR” (BAVOX PATENT) Gives a phenomenal uniform flow of pure air instantaneously delivered :: up to the required pressure :: Inflates Tyres (from flat) in 60 seconds The HF{H. W. Frost - Coachwork Inspector} “Rotoflator” is a four-cylinder rotary air compressor which gives a phenomenal uniform flow of pure air up to the required pressure. It is designed upon principles which have already been used with remarkable success in other directions, and its present application to tyre inflation is, we believe, fraught with big possibilities. Fig. 542, shows the internal arrangement of the compressor. It will be appreciated that adequate lubrication and oil-free air delivery are two of the most important considerations. These somewhat conflicting interests are satisfied by the fact that the air enters and leaves the compressor through the hollow centre spindle, while the lubricating oil is thrown outwards by centrifugal force and is always located at the periphery of the fast moving rotor. So effective is this action that the compressor is adequately lubricated for high speed running without any intermingling of oil and air. No oil filter is required. Absence of hammer in the air flow is an important characteristic. A multiplicity of small impulses—6,000 per minute—takes the place of the “thump, thump,” of the reciprocating compressor, and the air is delivered direct to the tyre without harmful shock. For this reason, no air reservoir is needed, and the losses occasioned by this addition are avoided. The durability of the HF{H. W. Frost - Coachwork Inspector} “Rotoflator” has been well established. At the Citroen Works, Paris, 100,000 tyres have already been inflated by one of these Compressors, in regular use, day in, day out, throughout the year. Such a test is far more exacting than can be anticipated under ordinary conditions. The HF{H. W. Frost - Coachwork Inspector} “Rotoflator” is supplied in two models for ordinary garage use, and in a special model for inflating giant tyres. Owing to its small size and extreme simplicity the “Rotoflator” is also eminently suitable for use on cars, and two special models are available for this purpose. Fig. 542 The above illustration shews the internal arrangement of the HF{H. W. Frost - Coachwork Inspector} “Rotoflator.” It will be seen that the body of the compressor is mounted on a central spindle, about which it rotates. An eccentric cam on this spindle transmits a reciprocating motion to the four cylinders, the pistons being relatively stationary. Air enters at one end of the spindle and is delivered at the other end. Suction and delivery ports (no lift valves) are contained within the cam. | ||