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).
Testing procedures for rear road springs, shock dampers, and axle strength.
| Identifier | ExFiles\Box 3\1\ 01-page181 | |
| Date | 12th February 1913 | |
| Re Road Springs (continued). can be obtained at the rear of the can with the present springs unoiled and no shock dampers. The system of oil shock damper in which the rebound is checked hydraulically is, I still think, the best, and nearly 12 months ago I asked that a pair of these should be tested on the rear of the cars, Renault and others were somewhat similar, but I do not think that they had our special feature of working in one direction only, that is in our idea the wheel should be very free to go over a lump but the axle would be checked from falling into a hole. In testing the strength of the back axle by the bumping (by log) I have the impression that we used present system of inverted spring to control the axle sideways and that they performed this duty without shewing any distress or the axle shewing any signs of moving sideways due to their want of control. If, however, the 3/4 eliptic were used, please at once arrange a test to be made on our present standard springs and fitting, the new light axle might be used in this test - two tests in one. In addition to going over the test of the bumping effect I should like the following test to be made. "Z" Prevent the wheels of the chassis from sliding sideways, drag the chassis by known forces say, 250, 500, & 1000 lbs. (by wire ropes, pullies and weights in a pit) alternately to the right and the left and measure the relative movement of the chassis-frame and the axle (central box not road wheels). "X" Also holding the chassis from running back drag the back wheel back first the left and then the right and measure the same as "Z". Compare the present practice with A - scheme used in 1400 and also B in 1700 before the introduction of the inverted spring. Paragraph "X" is very similar to the bumping test but a steady load is suggested so as to enable the movement to be measured whereas the bumping test is to smash things up and to find the weak spots. F.H.R. | ||