Anthony George Maldon Michell was an English-born engineer that was educated at the Universities of Cambridge in England and Melbourne in Australia. He invented the Mitchell thrust bearing that was patented in 1905. This device when equipped with the one-half ball and pin seen below, and inserted into a matching cup in the bottom of a piston, could drive a round slanted plate as seen below and transfer reciprocating motion into rotary motion.
Crankless Engines LTD. was formed in Melbourne, Australia in 1920 to develop and manufacture a new engine design Michell invented in the mid-teens using this idea. The crankless engine was based on a simple yet ingenious method of eliminating many moving engine parts by replacing the crankshaft, connecting rods and the bearings of a conventional engine with the assembly below.
Starting in 1923, the shop in Melbourne produced a number of both large and small engines. By 1927, the company had constructed over eighty of them in various different types. The general lack of interest in the design by major American and British auto manufacturers led the company to stop producing its engines around 1930, but it did licence the design to be built by others. Crankless Engines continued into closing in early 1945.
Shown above and below is a small five cylinder engine, clutch and transmission assembly. The head of the engine including: the intake, and exhaust manifolds (fined), valve train, twin spark plugs and carburetor can be seen below left. Below right is another view of the power plant with the valve cover installed. You can learn more about Mitchell and his designs at Engineers Australia, photos from the Museum Victoria. You can also view the Macomber Rotary Engine, a similar wobble-plate design that used connecting rods and was built here in the U.S..