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).
Instruction and feature leaflet for a Hasler revolution and speed indicator tool.
| Identifier | ExFiles\Box 33\5\ Scan038 | |
| Date | 9th September 1922 | |
| HASLER REVOLUTION, CIRCUMFERENCE & CUTTING SPEEDS INDICATOR. IN THREE SECONDS, WITHOUT THE AID OF A WATCH, THE NUMBER OF REVOLUTIONS OF A REVOLVING SHAFT CAN BE TAKEN. ALSO THE CIRCUMFERENCE OR CUTTING SPEED OF ANY ROTATING DISC. Clockwork, in the interior of the instrument, automatically engages the indicating mechanism when the instrument is started and releases same after three seconds; during this period the indicating mechanism is in direct communication with the driving shaft of the instrument, thus providing an exact record in a shorter unit of time than would be possible with tachometres based on the centrifugal or magnetic principle. Other important features of the instrument are :— Anti-magnetic, can therefore be used with impunity in electric power stations, etc. An uniform dial graduation, on which any number of revolutions up to 10,000 can be read with equal accuracy. The driving shaft can be rotated in either direction. The accuracy of the instrument is independent of the variable stresses of the springs or friction of the bearings. Not affected by vibration or change in temperature. It can be pressed on the moving body firmly without affecting the time element. The pointers remain on the figures arrived at until re-set. INSTRUCTIONS FOR USE. For Revolution Counting:— 1. Set pointers to zero by means of button at back. 2. Place friction point in countersunk hole of moving shaft. 3. Press and immediately release button at side, thus starting clockwork, the number of revolutions per minute being read off the black figures. For Circumference & Cutting Speeds:—Proceed as for Revolution counting, holding the friction roller against moving body, reading the Circumference and Cutting Speed in yards per minute from the red figures. HASLER TELEGRAPH WORKS, 26, VICTORIA STREET, WESTMINSTER, LONDON, S.W. Telegrams: SIVAD, LONDON. Telephone: 431 VICTORIA. | ||