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 memorandum detailing tests and construction of Delco Lovejoy hydraulic dampers.
| Identifier | ExFiles\Box 28\1\ Scan204 | |
| Date | 30th January 1931 | |
| K832 To R.{Sir Henry Royce} From Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. to Da.{Bernard Day - Chassis Design} E.{Mr Elliott - Chief Engineer} c. to By.{R.W. Bailey - Chief Engineer} Ha/Rm.{William Robotham - Chief Engineer}2/MJ.30.1.31. X-35 DELCO HYDRAULIC DAMPERS. We have been carrying out tests on one of the latest type Delco Lovejoy dampers that is, brought back from America. It is apparent that this damper is modelled on our original hydraulic, first fitted to the Phantom in Oct. 1926. The main dimensions are almost identical. The resultant production is obviously the outcome of extensive development and one is forced to admire the way they appear to have overcome the problems that have troubled us and at the same time simplified the damper until it can be produced for considerably less than £1. We are sending you under separate cover a sectioned case and piston for your inspection. The damper has a number of features that we have already in the new/piston damper, in particular spring loaded intermediate lever to operating piston, non spring loaded gland, very stiff shaft and levers (deflection curve shown on sheet 1), absence of air vent etc. They have also several features that we have not got which we consider worthy of attention. DAMPER CONSTRUCTION. (1) Horizontal Replenishing Valves in Piston. We think that these are very advantageous because - (a) With the vertical seat dirt is less likely to cause the valve to remain open. We have proved on petrol pump relief valves that dirt falls off a vertical seat. (b) The inertia of the ball helps it to open on the replenishing stroke. (c) Having no filter, this position is better than the floor of the damper. (d) The passages are short, unrestricted, and easily drilled. (2) Valve Passages Low Down in Cyl. and Horizontal. The valve chambers are horizontal and vent one into the other which prevents air being trapped. This enables them to do away with an air vent and use increased piston clearance .003 to release the air from the pressure chamber, since the highest point is the top of the piston. They do not undercut the ends of the bores presumably to avoid trapping air. The drilling of the valve passages is exceedingly simple. | ||