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Ohio State Engineer

Title:

Creators: Johnstone, Donald T.

Issue Date: Mar-1927

Publisher: Ohio State University, College of Engineering

Citation: Ohio State Engineer, vol. 10, no. 3 (March, 1927), 12, 18, 20.

URI: http://hdl.handle.net/1811/33874

Appears in Collections: Ohio State Engineer: Volume 10, no. 3 (March, 1927)

12 THE OHIO STATE ENGINEER SLEEVE VALVE ENGINES

By DONALD T. JOHNSTONE, '29 HE advent of the automobile into modern Knight Company, and the Yellow Sleeve Valve industry has given rise to extensive re- Works. Of these, the Willys-Overland Company search and experimental on valves is the largest producer. and valve gear for the internal combustion The single sleeve valve invented by P. engine, consequently, we may classify our present Burt and commonly known as the Burt-McCal- automobile engines by the type of valve and valve lum, or Argyll engine, is now used in Europe but gear with which they are equipped. The two pre- promises to become an extensive American prod- vailing types are the and sleeve uct due to the asquisition of the basic patents by valve with their respective gear. Of the many the Continental Motors Corporation, of Detroit, sleeve valve engines on which patents have been Michigan. taken out, only two have come into extensive com- As its name implies, the distinguishing feature mercial use: the double sleeve valve, invented by of the Knight double sleeve engine is the valve Charles Y. Knight, an American automobile engi- construction. The valve functions are performed neer; and the single sleeve engine, invented by by two concentric ported sleeves which are placed P. Burt, a Scotch engineer. between the wall and . These Charles Y. Knight was the pioneer of sleeve sleeves are given a reciprocating motion past valve engine design. In 1905 Knight began work ports in the cylinder walls to admit and release along this line and built a equipped with the the gases. Each sleeve has an exhaust port on first sleeve valve engine. His principal desire one side and an inlet port on the opposite side, was to eliminate the noise which the poppet valve the passage for either the inlet or exhaust being engine created, for at this early stage of motor open when the three ports on a particular side car development many of the poppet valve en- are in registry. As the sleeves move upward they gines were made with much of the valve train pass into an annular space between the cylinder outside of the case so that the noise of metallic wall and an especially constructed surfaces coming into contact with each other so that during the compression and strokes could not be muffled. At the time the Knight the gases do not come into contact with the cyl- engine was invented, the best engines were very inder wall, but are separated from it by two lay- noisy even though operating speeds were low as ers of cast iron and two films of lubricating oil. compared with out present engine speeds. The inlet passage begins to open when the bottom The sleeve valve design was not considered edge of the port in the outer sleeve, moving down- practical by American manufacturers at this wardly, passes the top edge of the port in the in- time; but after convincing tests Knight succeeded ner sdeeve, also moving downwardly but at a in selling his British rights to the Daimler Motor slower rate. The inlet passage closes when the Company, of Coventry, England. The Daimler bottom edge of the port in the inner sleeve, mov- Company was the largest producer of expensive upwardly, passes the top edge of the port in the motor in England, consequently it occupied outer sleeve, also moving upwardly. This passing a very important place in the British motor car of the edges of the ports in the sleeves takes place industry. Immediately following the adoption while they are opposite the inlet port in the cyl- of the sleeve valve engine by Daimler, Knight inder wall. The inlet ports of the two sleeves placed his rights with one manufacturer in each also come into registry 360 degrees of the of the principal countries of Europe. The Mer- motion later, when the piston has started on its cedes concern secured the German rights, the power , but these ports are then high up Minerva Company of Antwerp the Belgian rights, between the cylinder wall and cylinder head, and and Panhard-Levassor of Paris the French rights. the port in the inner sleeve is sealed by a ring These firms were recognized as the foremost in in the cylinder head. The strokes of both sleeves motor car manufacture in Europe, so his success are alike, but the lengths of their connecting rods with these firms created a great interest through- are different. out the automobile industry of the world. The Sleeve vailye engine ports can be made larger British Daimler concern adopted the new engine than is consistent in poppet valve engine design for their total production and in 1908 exhibited due to the fact that the sleeve valve engine pro- models equipped with this engine at the London duces less noise when operating. The fact that show, but the other European manufacturers exceptionally large port area can be obtained turned only a part of their production to the with the sleeve valve never has been an important Knight enigne. factor in the design of American racing car en- After his striking success in Europe, Knight gines because these engines are not designed for returned to this country, where he planned to quiet operation. The desired port area can be ob- place his patents with four manufacturers, in- tained with the poppet valve if the noise they stead of one as in each of the countries of Europe. make is no objection. To obtain maximum effi- The licenses were eventually placed with the F. B. ciency with the poppet valve, the lift should be Stearns Company, the Columbia Motor Car Com- one-fourth the clear diameter and rapid, but this pany, the Stoddard-Dayton Company, and the construction is not adhered to except in racing en- Moline Aotomobile Company. These four licenses gines where the height and lift are determined are now controlled by the Willys-Overland Com- only by the physical properties of the metals. At pany, the F. B. Stearns Company, the Sterling- (Continued on Page 18) 18 THE OHIO STATE ENGINEER

SLEEVE VALVE MOTORS haust valve head; the is so surrounded (Continued from Page 12) with water that it is sufficiently cooled; and the piston head has never given any undue trouble. moderate speeds the specific output of sleeve valve Compression ratios are as high in the present engines is apparently about 15 per cent greater sleeve engine as in any poppet valve engine, so it than poppet valve engines. seems that this saving of heat tends to greater The sleeves are operated by their connection mechanical efficiency. to an eccentric shaft which is driven from the Formerly, lubrication of the sleeves was the at half engine speed. The stroke in greatest problem in the sleeve valve engine de- the older type engines at least, was from 1 to 1% sign because, with the original splash lubricat- . The reciprocating motion of the valve ing system, the oil would not travel upward mechanism creates a problem of balance in this along the surface of the sleeves. At the present engine and the speed of the original Knight en- time, some makers have installed pressure lubri- gine had to be kept comparatively low because of cating systems which have overcome the original the inertia of the sleeves, but refinements in the troubles, and others that depend on the splash sleeve construction have cut down weight so that system, have provided holes and grooves for oil now the sleeve valve engine can be operated at reception and distribution. Refinements of the speeds equal to the average poppet valve engine. past few years have practically eliminated the ob- Tests have shown that the power required to op- jections to the sleeve valve engine due to lubrica- erate the valve gear does not lower ;the mechani- tion difficulties. cal efficiency of the engine to any appreciable ex- The latest models of the Daimler motor cars tent, although greater starting is required are equipped with steel valve sleeves, and due to due to congealed oil on the surface of the sleeves. this fact an increase of power has been secured The distinguishing point about the 'valve gear is which places this particular sleeve valve engine that the valves are positively operated and valve on a level basis at least as high as the best of timing is therefore absolutely independent of the poppet valve engines intended for normal use. speed. The Daimler Motor Company manufactures four The construction of the different engines ranging from 114 cubic inches and cylinder in the Knight engine allows a piston displacement developing 55 brake horse- greater percentage of heat energy, released by power, to 350 cubic inches displacement develop- combustion, to be transformed into useful work ing 120 brake . The power increase than the construction of the conventional poppet in each case is at the top of the speed range and valve type allows. The proportion, of heat which results partly from the higher speeds made pos- passes into the cooling jacket varies with the sible by the use of steel valve sleeves. The steel ratio between the cooling area and the volume sleeves, which are about half as thick as the usual of the combustion chamber. It is important to cast iron sleeves, have white metal contact sur- have the cooling area as small as possible during faces applied by centrifugal process. The other the early part of the power stroke as the gases factors tending toward the power increase are, are then at the highest temperature and they lose the larger and rectangular valve ports permitted energy to the cooling jacket most rapidly. From by the use of steel sleeves, the increase of com- this point of view, the most favorable form of pression ratio, and the use of pressure lubrica- combustion chamber is a sphere apd this form is tion. Formerly, a smoky exhaust was noticeable, more closely approached in the fKnight engine but Dailmer has overcome this difficulty by the than any other. Measurements, made by Profes- use of baffle plates below the sleeves. sor Riedler of the Charlottenburg Technical Col- lege on three different models of sleeve valve en- Panhard-Levassor of Paris has developed the gines, showed the difference in heat loss to the original Knight engine to a high degree of oper- water jacket to be from 4.9 per cent to 11.2 per ating efficiency until it now embodies many fea- cent less in sleeve valve engines-than in poppet tures for which the French firm holds patents. valve engines. They have recently placed a 450 horsepower avia- Conservation of heat in the working fluid dur- tion engine on the market that successfully ing the power stroke is due not only to the rela- passed the 240-hour French government test. This tively small extent of combustion chamber wall engine was the first Knight type aviation engine surface but also to the nature of this wall sur- to be successful in public competition. It was a face. At the beginning of the power stroke less 12-cylinder, V-type at 60 degrees and because of than half of the combustion chamber wall surface the absence of overhead valve gear the height was is directly exposed to the water jacket, this being only 35.4 inches. This compares with heights of the under side of the cylinder head. The rest of 47 to 49 inches for poppet valve engines, with the combustion chamber is separated from the overhead , of equal power. cooling jacket by three layers of metal and two The use of steel sleeves, in place of cast iron, oil films. The two sleeves and two oil films un- has been general in Panhard-Levassor automobile doubtedly furnish better insulation from the and avtiation engines for the past four years. water jacket, even though the exact amount is The steel sleeves give the advantage of less unknown. weight, reduced vibration, and economy in oil The slower rate of heat flow to the cooling consumption by reason of the smaller clearances jacket might be expected to cause trouble from which they render possible. The present steel overheating. In the conventional engine there are sleeve is only 1.5 millimeters thick while the usual three points that usually reach temperatures cast iron sleeve was 4 millimeters thick. The above the average of the combustion chamber port area also can be increased almost indefinitely wall, the exhaust valve head, spark plug, and pis- without having to increase the depth of the com- ton head. In the Knight engine there is no ex- (Continued on Page 20) 20 THE OHIO STATE ENGINEER

SLEEVE VALVE MOTORS The Burt-McCallum, or Argyll, sleeve valve en- (Continued from Page 18) gine is distinguished by having a single sleeve to perform the valve functions instead of two pression rings in the cylinder head. Apart from sleeves as used by the Knight engine. the use of sleeve valves, the outstanding feature The sleeve has a number of specially shaped of Panhard-Levassor engines is the white metal- parts at the top and a single universal driving ing of the inner surface of the outer sleeve and connection at the bottom. Two exhaust and two the walls of the steel cylinder. inlet ports appear in each cylinder while each Belgium recently adopted a Knight sleeve valve sleeve has but three ports, the middle port of the engine built by the Minerva Company for use sleeve serving alternately as inlet and exhaust in government aviation service. Belgium's choice openings. On the stroke the middle port of this type of engine shows that the double sleeve in the sleeve uncovers one of the inlet ports in valve engine is making an important bid for ser- the cylinder and vice versa on the exhaust stroke. vice in areoplanes in Europe. The exceptionally big valve ports permit com- plete filling and scavenging of the cylinder with- The first notable test on a sleeve valve engine out any of the lubrication difficulties attending was made in 1909 before the Royal Automobile other types. Club of Great Britain on a 4-cylinder Daimler en- gine of 3%- and 5-inch stroke. This The sleeve is actuated by a short shaft con- engine was first placed on a bench and run con- sisting of a disc with an eccentric pin on the end tinuously for 5 days 12 hours and 58 at engaging in a universal joint at the bottom of the 1,000 feet per piston speed where it devel- sleeve. This disc is driven by means of a skew oped 38.83 average horsepower with a con- gear from the valve shaft, the equivanent of a sumption of 0.668 lb. per horsepower hour. After shaft on the poppet valve engine. The disc, this test it was placed in a 3,300-lb. car, driven rotated by the valve shaft and eccentric pin 2,143 at an average speed of 41.88 miles thereon, imparts to the sleeve a combined vertical per hour, then again placed on a bench for 5 and horizontal travel, as the universal joint al- hours' time where it developed 38.96 average lows the sleeve freedom to partially rotate on its horsepower on 0.667 lb. per horsepower fuel con- axis. The resultant path of the sleeve is elliptical. sumption. Inspection showed no appreciable Each cross shaft is run at half engine speed, wear on fitted surfaces and that the cylinders and therefore the ports in the cylinders are uncovered were notably free from carbon. by corresponding ports in the sleeve once in a complete revolution of the valve shaft, or two The first run of any importance in America revolutions of the crank shaft. The action of the was made in 1913 in New York City by a Moline- sleeve valve is positive at all engine speeds and Knight 4-cylinder engine of 4-inch bore and 6-inch improves with use. stroke. At the end of a continuous run of 337 hours under full load, the engine was examined The popularity of the sleeve valve engine is for wear and carbon and found to be in perfect rising. This fact is especially noticeable in the condition. European automobile and aeroplane industries, but at this time some of the largest manufactur- Parallel to the adoption of the Daimler-Knight ers of poppet valve engines in America are ex- by the London General Omnibus Company, which perimenting with various types of sleeve valve as early as 1914 had 2,600 buses in daily use in engines. This fact promises a more general adop- London, was the adoption of the Moline-Knight tion of the sleeve valve principle in our American by the Fifth Avenue Coach Company, of New cars of the future. York. City, and the Chicago Motor Coach Com- At the present time sleeve valve equipped cars pany, of Chicago. More recently, the Knight, cost more money than corresponding poppet valve after a long period and carefully observed test equipped cars; they are slightly harder to start in 125 taxicabs, has been adopted as standard by in cold weather due to the large sleeve surfaces the Yellow Cab Company, of Chicago. The cabs being covered with congealed oil; and the en- of this company averaged about 45,000 miles each gines may be badly damaged if operation is at- last year. tempted without sufficient quantity, or the right Since its invention, the sleeve valve engine has kind, of oil. These disadvantages are apparent, proven very satisfactory under endurance, power, but they are gradually being overcome and there and economy tests, but it has only been within the is no doubt that they will be practically elim- last three years that the speed of the sleeve valve inated in the near future. The advantages of the engine has rivaled that of the poppet valve en- sleeve valve engine, however, are such that its gine. Compartively recent speed tests have growing popularity is well deserved and we may proven that the Knight will equal the poppet valve expect to gain by using the sleeve valve engine: in this field. A 4-cylinder Panhard-Levassor en- greater fuel economy, because it is practical to gine of 3%-inch bore and 5y2-inch stroke, on use higher compression, less heat is lost to water, Mpntehiry track, has established the following and there is less valve leakage; increased power, records: 50 kilometers at 114.1 miles per hour; because of improved sealing with carbon; quiet 50 miles at 115.06 miles per hour; 100 kilometers operation, because of continuous, regular valve at 115.19 miles per hour; and a distance of 115.4 action with no metallic surfaces making contact; miles in one hour. This engine was capable of greater mileage without mechanical attention, be- turning up to 5,000 . A cause of no valves to grind or adjust; less trouble Voisin-Knight set a world's record for six hours from carbon, as pistons and cylinder heads keep of just over 600 miles, and in November, 1925, notably free and seldom need cleaning; and less this French car averaged 107 miles per hour for dilution of crank case oil, because of higher oper- 500 miles. ating temperatures.