Crankless Engines (Aust) Pty Ltd was formed in Melbourne in 1920 to develop and manufacture a new engine design invented in about 1917 by British-born, Australian resident Anthony George Maldon Michell. One of Australia's most accomplished, if little-known inventors and engineers, Michell, born in 1870, lived with his parents at Maldon in Victoria until the family moved to Melbourne in 1877 where he attended the State School in Punt Road, South Yarra. He completed his secondary education at Cambridge University in the United Kingdom and returned to Melbourne in 1890. He subsequently graduated from the University of Melbourne with honours degrees in Civil and Mining Engineering. He later completed a Masters degree in Civil Engineering.

The crankless engine was based on a simple yet ingenious method of eliminating many moving parts by replacing the crankshaft, connecting rods and bearings of conventional engines with a moving slanted plate which transmits motion to pistons via lubricated slipper blocks attached to the pistons with universal joints. Lubrication of the slipper blocks allows them to slide over the slanted plate with a minimum of friction. The slippers do the work of conventional connecting rods attached to a crankshaft. By equalising the mass of the pistons with their actuating slanting plate, a very good dynamic balance can be achieved leading to smooth operation. The crankless design is compact as it removes the need for connecting rods and space for a crankshaft. The crankless engine was derived from A.G.M. Michell's earlier invention of a new design for a thrust bearing which he patented in January 1905. This bearing uses slanting slipper pads engaging with fixed collars with an oil film being introduced to take much of the load. This type of bearing was ideal for large stationary power plants and marine engines where considerable power and thrust are required.

Initial development was undertaken in 1907 by Geo. Weymouth Pty Ltd in Melbourne which manufactured a centrifugal pump for Cohuna in Victoria using the Michell bearing. The design was later used by the Imperial German Navy, and from 1913 by the Royal Navy in warships ranging from destroyers to the battleship HMS Hood. It remains the standard marine thrust bearing although Michell received little financial reward for his invention. Crankless Engines (Aust) Pty Ltd established a factory at 129 Greeves Street, Fitzroy and an office at 9 Queen Street in Melbourne. Directors of the firm included former Victorian Attorney-General Arthur Robinson (Chairman), A.G.M. Michell and Richard Casey (later Baron Casey of Berwick). Casey wrote in 1973 that he and a group interested in mechanical developments had convinced a reluctant Michell to form the Crankless Engine firm to market the design. Michell then asked Casey to show the engine to the major motor vehicle manufacturers in the United States. Accompanied by a mechanic, Casey went to the US in 1921 with an 8-cylinder crankless motor vehicle engine. Extensive bench testing of the engine was completed by General Motors at Dayton, Ohio and by Ford at Detroit. Casey related that the crankless design was found to be about 10% more efficient than a conventional engine but that the cost of retooling did not justify the improvement and the large US auto firms declined to adopt it. Another crankless engine was fitted to Michell's own Buick car and used regularly including a long trip from Melbourne to Sydney and back in 1924.

Although its use in motor vehicles failed to generate interest, the crankless design was eventually used for gas engines and compressors. A pair of 50 horsepower gas engines and compressors were sold to the Australian Gaslight Co. in Sydney to boost town gas supply. Attempts were also made in the mid to late 1920s to interest British manufacturers in proposals for crankless aero engines and Rolls-Royce produced a prototype. Later Speco in the USA developed a 4-cylinder crankless aero engine. By the late 1920s the Crankless Engine company was no longer producing its own engines but did licence the design to be built by others. Crankless Engines was placed in receivership in February 1945. Michell Bearings is an unrelated company in Britain which is now part of the Rolls-Royce Group. Michell was recognised with the award of a Fellowship of the Royal Society in 1934, the University of Melbourne's Kernot Medal in 1938, and in 1942 he received the James Watt International Medal by the Institution of Mechanical Engineers in Britain. He lived with his brother and sisters in Camberwell until his death in 1959.

More Information