Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 132,950 pages of information and 210,197 images on early companies, their products and the people who designed and built them.
of Canley, Coventry
of Hill Street, London W1 (1964)
Post-WWII: Edgar De Normanville developed the epicyclic concept for use as an overdrive facility. He interested Axel Wickman in the idea and they formed Auto Transmissions Ltd of which de Normanville became technical director. 
1950 Laycock Engineering Co manufactured the Laycock-de Normanville overdrive system under licence from Auto Transmissions Ltd. The company continued to supply overdrives for many years.
1951 Sydney Henry Ashby and the company patented an epicyclic gear power transmission system.
1952 Edgar de Normanville and the company patented an epicyclic gear power transmission system.
1963 Motor Show exhibitor. Designers of Laycock de Normanville Overdrives.
1964 Axel Charles Wickman was the inventor of a power transmission system for gas turbines which was patented by the company.