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).
Composite and split-skirt piston designs for engines.
| Identifier | WestWitteringFiles\N\2October1925-December1925\ Scan25 | |
| Date | 10th October 1925 | |
| R.R. 493A (50 H) (D.D. 31, 12-6-25) J.H.D. EXPERIMENTAL REPORT. -5- Expl. No. REF Hs{Lord Ernest Hives - Chair}/ACL/LG10.10.25. be better suited to take the side thrust than the one we employed for our experiments and at the same time retain the same desirabl characteristics. Another advantage which may be obtained is that when using 'shrunk in' gudgeon pins - as is our standard practice - it would tend to prevent the piston skirt from bulging sideways when the piston cooled down due to the difference in expansion of the piston and the pin. A design for a composite piston which we think may be worthy of consideration is one in which the expansion of the skirt is controlled by means of a steel carrier, or cantilever, which carries the gudgeon pin. The pressure plates would be of aluminium and could be quite flexible at the edges and each cover about 90° of the cylinder bore. A piston this type, should operate with approximately the same clearance as necessary for cast iron and at the same time would retain the desirable characteristics of lightness and thermal conductivity, also gudgeon pin fixing would be comparatively easy. A sketch of this scheme is attached. We are still continuing experiments but at the present time consider the type of piston which shows the most promise is the one with the split both sides of the skirt, and suitably designed one of this type, we think, would be quite satisfactory. Hs{Lord Ernest Hives - Chair}/ACL. | ||