Nutating disc engine
A nutating disc engine (also sometimes called a disc engine) is an
Operation
In its basic configuration the core of the engine is a nutating non-rotating disc, with the center of its hub mounted in the middle of a Z-shaped shaft. The two ends of the shaft
Power is transmitted directly to the output shaft (the crankshaft), completely eliminating the need for complicated linkages essential in a conventional piston engine (to convert the piston's linear motion to rotating output motion). Since the disc does not rotate, the seal velocities are lower than in an equivalent IC piston engine. The total seal length is rather long, however, which may negate this advantage.
The disc wobbles inside a housing and, in its simplest version, half of the single disc (one lobe) performs the intake/compression function while the other lobe performs the power/exhaust function. The disc lobes can be configured to have equal compression and expansion volumes, or to have the compression volume greater than or less than the expansion volume. This means that the engine can be self supercharged (see supercharger), or operate as a Miller cycle / Atkinson cycle.
Patents and production history
U.S. patent number 5,251,594 was granted to Leonard Meyer of Illinois in 1993 for a "nutating internal combustion disc engine".[1] The Meyer Nutating Engine is a new type of internal combustion engine with higher power density than conventional reciprocating piston engines and which can operate on a variety of fuels, including gasoline, heavy fuels and hydrogen. The patent made reference to various 20th-century nutating engines in the United States, but no reference at all to the original Dakeyne engine, described below, in its prior art. The similarity to its 166-year-old hydraulic predecessor is strikingly evident, the main change being that the disc is not entirely flat but slightly convex.
The details of operation and potential of the Meyer nutating disk engine have been described by Professor T. Alexander (publishes as T. Korakianitis) and co-workers.[2][3][4][5]
A single prototype has been run briefly under its own power, with a power- to-weight ratio equal to those of typical current four-stroke engines. It is claimed by the authors of the developer/US Army Research Laboratory/NASA technical evaluation report that a production version of the new engine (for UAV applications) might provide a power-to-weight ratio of 1.6 hp/lb or 2.7 kW/kg.[6] This is slightly better than current automotive production engines[7] but nowhere near the Graupner G58[8] or the Desert Air DA 150.[9]
A company called McMasters, previously headed by successful American entrepreneur
History
Dakeyne hydraulic disc engine
In the 1820s the mill owners Edward and James Dakeyne of
A larger model was constructed to drain lead mines at Alport near Youlgreave and many steam versions were subsequently built by other people.
Davies and Taylor
The first people to develop steam-powered disc engines based on the Dakeynes' design were George Davies and Henry Taylor who patented their engine in 1836. It was fitted with valves to control the admission of steam and also differed from the Dakeynes' version in that the axis of the engine was horizontal and the casing of the engine rotated around the disc, the opposite of the original. More patents followed over the next eight years, mainly introducing expansive working and improving the engine's sealing.
In 1836 Davies and Taylor granted manufacturing rights for the engine to Fardon and Gossage, owners of a salt works. At the same time Davies was working on a canal tug with a disc engine driving a paddle wheel at the stern. By 1838 a 5 hp engine was in use at the salt works pumping brine.
In 1839 Davies, Taylor, Fardon and Gossage conveyed manufacturing rights to the engine to the Birmingham Patent Disc Engine company. As Superintendent of the Company, Henry Davies was responsible for all design and manufacture, while Gossage was a director. In February 1841 the Board reported that 26 engines had been completed, further engines totalling 260 horsepower were in progress, and a total of 500 horsepower were on order. They could make engines ranging from 5 to 30 horsepower and were currently making engines for a railway carriage. An article in a French journal of 1841 reported that a 12 hp engine had been in use for six months as a winding engine at Corbyn's Hall Mine, Dudley, which could lift a load of 1 ton 180 ft in 1 minute. The disc engines cost from £96 for an 8 hp machine to £300 for a 30 hp model.
Ransomes of Ipswich (who were later to become the well-known agricultural engineers
By 1840 a canal boat, The Experiment, powered by a Davies engine, was being used for propeller testing, and in 1842 Davies installed a disc engine and disc pump in a canal barge which he demonstrated by draining half a mile of the Stourbridge canal. The same year, a 5 hp engine was fitted in one of HMS Geyser's pinnaces. However, trials on the Thames and for the Directors of the Grand Junction Canal failed to convince either the Admiralty or the canal owners.
Nevertheless, there was a growing interest in using steam power on the canals, and the small beam of canal boats very much favoured disc engines. Davies saw his opportunity and built an iron-hulled canal tug with a 16 hp BPDE engine in 1843. To minimise wash he fitted four propellers spaced along a shaft the length of the boat and enclosed in a tube below the waterline. There were two of these propulsion units side by side for a total of 8 propellers. It worked well enough to convince the Directors of the Birmingham and Liverpool Junction Canal to order six tugs which could tow as many as sixteen barges a day at a reasonable speed. In use, a train of six to eight barges left Ellesmere Port and Wolverhampton each day, carrying an average of 100 tons. Unfortunately nobody had considered how the barge train was to transit through the canal locks and shallows. Each such obstruction meant that the train had to be uncoupled and the barges individually manhandled or towed by horse through the obstruction before the train was reassembled on the other side. This negated the benefits of the tug and train and in 1845 the canal's Directors removed the tugs from service.
In 1844 the BPDE collapsed.[12] The workshop equipment, various completed engines and quantities of work in progress were offered for sale. During legal proceedings in 1851 following the bankruptcy of two of the BPDE's principal investors, it was said that the disc engine had not made a profit and that to have relied on it as a realisable asset "was absurd".
Bishopp
A competitor to Davies and Taylor was former locomotive engineer George Daniell Bishopp, who had Donkin & Co build his first engine in 1840, and a patent was granted in 1845. The partners Barnard William Farey and Bryan Donkin Jr. patented improvements to the basic design; Donkin had worked with Bishopp on his original engine, while Farey was an employee of Donkins.
Bishopp's engine met with some scepticism from the trade press when it was launched on the market. But Bishopp had opted to revert to the Dakeynes' original design which had a yoke which took most of the dynamic forces and greatly reduced the load on the bearings and seals. In the event that there was any leakage, the seals were adjustable. In addition, Bishopp had his engines produced by companies with recognised engineering capabilities rather than carrying out his own manufacturing; as well as Donkin's, some of his first engines were built by Joseph Whitworth & Co of Manchester. Another engineering company with a very good reputation was G. Rennie and Son of London who were so convinced of the engine's potential that in 1849 they employed Bishopp as their foreman of works with specific responsibility for the disc engine.
By 1849 a number of Bishopp engines had been sold, and one was used with great success to run the printing presses of the
In 1853 a disc engine 13 inches in diameter was purchased from Rennie to propel a 55 foot Russian gunboat, which it did at a speed of 7 knots (13 km/h; 8.1 mph).[13]
At the time the advantages of the disc engine were listed in 1855 by
- It was as much as half the weight of a conventional steam engine of equivalent power
- It had the advantages of rotary steam engines without their inconvenience
- It was more economical in terms of fuel: as much as 18%
- It was capable of higher RPM without needing gearing
- It was suited to high-pressure use
Disc engines ultimately fell into disuse because of competition from modern high-speed steam engines, which were small and light and could offer features such as compounding. Additionally, conventional engines did not require the same precision manufacture as disc engines and steam leakage was not a problem.
Water meters
The nutating disc meter, which uses the same geometry and concept as the Dakeynes' original engine,
See also
References
- ^ US patent 5,251,594, Meyer, Leonard, "Nutating internal combustion engine", issued 1993-10-12
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- ^ The Nutating Engine—Prototype Engine Progress Report and Test Results, (Peter L. Meitner, U.S. Army Research Laboratory, Glenn Research Center, Cleveland, Ohio),(Mike Boruta and Jack Jerovsek, KINETIC/BEI LLC, South Elgin, Illinois) NASA/TM—2006-214342 ARL–MR–0641 U.S. ARMY RESEARCH LABORATORY, Fig. 6.
- ^ Sports Car Designer [dead link]
- ^ "Two stroke engines for UAV: info collected by BML". Archived from the original on 2009-03-01. Retrieved 2007-12-31.
- ^ "Desert Aircraft". Archived from the original on 2007-09-17. Retrieved 2007-12-31.
- ^ McMaster Motor
- ^ Nixon, Frank (1969). The Industrial Archaeology of Derbyshire. David & Charles. p. 102.
- ^ Burn, Robert Scott (1857). The Steam Engine. London: Ward and Lock. pp. 108–109.
- ^ a b The Mechanics' Magazine. London: Robertson, Brooman, and Co. 1855. pp. 267–268.
- ^ Niagara Meters: Nutating Disc Drawing
- ^ Hersey Meters – 400 Series Positive Displacement Disc Water Meter
External links
- Patent document from USPTO
- The Romping Lion - the story of the Dakeyne Disc Engine
- Description of engine - Cornell university(subscription required) and links to three illustrations, one from The Mechanics Magazine, 1833.
- article re: Len Meyer/ Baker engineering Inc. contract to develop engine
- Engineering TV article
- Animation 1 of McMaster Engine
- Animation 2. of McMaster Engine
- History
- Wigfull, Phil. "The Romping Lion: The story of the Dakeyne Disc Engine". Archived from the original on 2012-02-09.
- Inventors - The Romping Lion, Peakland Heritage site
- The Dakeyne Hydraulic Engine by Phil Wigfull at the Wayback Machine (archived July 1, 2007)
- The Dakeyne brothers. Thurston, "History of the Growth of the Steam Engine"
- Technical reports