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).
Technical discussion on the performance of rubber buffers in shock absorbers, outlining their disadvantages and proposing future improvements.
| Identifier | ExFiles\Box 68\2\ scan0214 | |
| Date | 30th March 1928 guessed | |
| contd :- -4- (4) That if we have no velocity pressure increase, an 80 lbs. ball end load from the shock absorber is as much as we can use without spoiling the low speed ride. (5) That it is erroneous to say that a hydraulic shock damper with a velocity pressure increase need be affected to an objectionable extent by temperature, provided the pressure rise is obtained by k.e. loss. In the future we feel that we should like to do away with the rubber buffer and make the damper do its work perhaps leaving a thin .250" strip to prevent metal-to-metal contact. We do not like the rubber buffer because :- (1) It has no damping practically, and when the axle hits the buffer it is most in need of damping. The buffer actually urges the axle away from the frame instead of restraining it at the commencement of its travel down. (2) The buffer rating is too high considering that it occupies 1 1/2" between the axle and the frame. Only .5" of this is normally used, the buffer monopolises the rest even when it is working. If the whole 1 1/2" could be employed the passengers could get less jar, and the axle more damping. We attach curves shewing the road spring cum buffer rating, and the rating of the buffer only with its internal damping. Therefore to do away with the buffer we want a great deal of damping at the extreme compression range of the axle movement. The other problem we have is, to separate velocity resulting from a high frequency from velocity caused by a large amplitude, in other words to have a pressure velocity increase contd: | ||