|||||||||| USO05507253A United States Patent (19) 11 Patent Number: 5,507,253 Lowi, Jr. (45) Date of Patent: Apr. 16, 1996 54 ADABATIC, TWO-STROKECYCLE ENGINE ing,” SAE Paper 650007. HAVING PSTON-PHASING AND John C. Basiletti and Edward F. Blackburne, Dec. 1966, COMPRESSION RATO CONTROL SYSTEM "Recent Developments in Variable Compression Ratio Engines.” SAE Paper 660344. 76 Inventor: Alvin Lowi, Jr., 2146 Toscanini Dr., L. J. K. Setright, "Some Unusual Engines,” Dec. 1975, pp. Rancho Palos Verde, Calif. 90732 99-105, 109-111. R. Kamo, W. Bryzik and P. Glance Dec. 1987, "Adiabatic (21) Appl. No.: 311,348 Engine Trends-Worldwide,” SAE Paper 870018. (22 Filed: Sep. 23, 1994 S. G. Timony, M. H. Farmer and D. A. Parker, Dec. 1987, "Preliminary Experiences with a Ceramics Evaluation Related U.S. Application Data Engine Rig.” SAE Paper 870021. Paul and Humphrheys, Dec. 1952, SAE Transactions No. 6, 63 Continuation of Ser. No. 112,887, Aug. 27, 1993, Pat. No. 5,375,567. p. 259. (51) Int. Cl." ......................................... FO2B 75/26 Primary Examiner-Marguerite Macy I52 U.S. Cl. .................................... 123/S6.9 Attorney, Agent, or Firm-Bruce M. Canter 58) Field of Search .................................. 123/55.7, 56.1, 123/56.2, 56.8, 56.9, 51 B, 193.6 57) ABSTRACT An engine structure and mechanism that operates on various 56) References Cited combustion processes in a two-stroke-cycle without supple U.S. PATENT DOCUMENTS mental cooling or lubrication comprises an axial assembly of cylindrical modules and twin, double-harmonic cams that 1,127,267 2/1915 McElwain .............................. 123/56.8 operate with opposed pistons in each cylinder through fully 1,339,276 5/1920 Murphy .................................. 123/56.8 captured rolling contact bearings. The opposed pistons are 1,808,083 6/1931 Tibbetts .................................. 123/56.9 2,076,334 4/1937 Burns ..................................... 123/56.9 double-acting, performing a two-stroke engine power cycle 2,243,817 5/1941 Herrmann. on facing ends and induction and scavenge air compression 2,243,818 5/1941 Herrmann ............................... 123/173 on their outside ends, all within the same cylinderbore. The 2,243,819 5/1941 Herrmann ... ... 23/196 engine includes a control system which utilizes twin barrel 2,243,820 5/1941 Herrmann ... ... 123/56 cams with adjustable axial and angular positions enabling 4,791,787 12/1988 Paul et al............................... 60/605.1 independent compression ratio and port phasing variation 4,856.463 8/1989 Johnston ..... 123/51 BA during operation. The engine control system comprises one 4,996,953 3/1991 Buck ...................................... 123/56.9 or more electrohydraulic servos to set and maintain the axial 5,058,536 10/1991 Johnston . ... 123151 BA and angular relationships of the cams either at extreme 5,215,045 6/1993 Vadnjal .................................. 123/56.8 positions or controlled to particular positions and schedules OTHER PUBLICATIONS thereof utilizing instantaneous piston position feedback information. P. M. Heldt Dec. 1943, "High Speed Diesel Engines,” Fourth Ed., pp. 308-311, 320-327. S. G. Timony, Dec. 1965, "Diesel Design for Turbocharg 16 Claims, 13 Drawing Sheets 2 16 52 50 - 44 14 2.2 2 34 22 liv42 32 2 300 zircreen rear frees ÉY freeler-- 2M AAAAAA CANARY ARAS A SAN FAAAAAAAA 2 a 1 2skerry's sixx rear are extraorra 2M 3O 34 49 f8 52 52 f4 50 " 46 32 2 U.S. Patent Apr. 16, 1996 Sheet 1 of 13 5,507,253 297 2€. 22° þ/ 9/2.*L2.Nos U.S. Patent Apr. 16, 1996 Sheet 2 of 13 5,507,253 U.S. Patent Apr. 16, 1996 Sheet 3 of 13 5,507,253 U.S. Patent Apr. 16, 1996 Sheet 4 of 13 5,507,253 As PISION RECIPROCATION PHASE TOC BDC TDC BDC SHAFTAAGLE O 90 /30 27() U.S. Patent Apr. 16, 1996 Sheet 5 of 13 5,507,253 24 2.2 23 HZ --- x%2D42 4 (2% 22 as Ly: E U.S. Patent Apr. 16, 1996 Sheet 7 of 13 5,507,253 S N S S S\ E N 242 VO N nN F Q) N 37 3. zé Z2 S. 24 24 YZ YS C (N N NNN & T NS His NY,NNZ Z U.S. Patent Apr. 16, 1996 Sheet 9 of 13 5,507,253 76 ) 94 6O U.S. Patent Apr. 16, 1996 sheet 10 of 13 5,507,253 S. ON N & S. r N s s (NN SS Sn ( N 1 QN Q N sk. N. Q St. SS N SJ N-- nS NS S S S.A & Q & SS SS R U.S. Patent Apr. 16, 1996 Sheet 11 of 13 5,507,253 154 U.S. Patent Apr. 16, 1996 Sheet 12 of 13 5,507,253 U.S. Patent Apr. 16, 1996 Sheet 13 of 13 5,507,253 VHSH–/vol_1/SQ/132/3767627/V7 // -677 5,507,253 1 2 ADLABATIC, TWO-STROKECYCLE ENGINE lubrication schemes to maintain their mechanical and struc HAVING PSTON-PHASING AND tural integrity and their weight and balance is highly sensi COMPRESSION RATO CONTROL SYSTEM tive to increases in cylinder working pressures and rotational speeds. Thus, prior art engines that operate on the diesel cycle are somewhat heavier and larger than their spark RELATED CASES ignition counterparts and they also present greater lubrica tion, cooling and balancing burdens. This accounts, to a This application is a continuation of U.S. application Ser. large extent, for the lack of acceptance, heretofore, of prior No. 08/112,887, filed on Aug. 27, 1993, now U.S. Pat. No. art type diesel engines for aircraft applications notwithstand 5,375,367, and incorporated by reference as if fully set forth ing their potentially superior flight-worthiness, safety, fuel herein. O economy and fuel flexibility characteristics. Various attempts have heretofore been made to overcome FIELD OF INVENTION some of these problems by designing diesel engines with large heat retention capacities. Examples of such "adiabatic This invention relates to uncooled, two-stroke-cycle, engine' are those manufactured by Adiabatic Inc. and Cum opposed-piston, uniflow-scavenging internal combustion 15 mins. These adiabatic engines utilize insulated parts, heat engines, and to piston phasing and compression ratio con tolerant components and high-temperature tribology or fric trols for such engines. Specifically, the engine relates to an tion controls. However, such friction controls require axial-cylinder, twin-barrel-cam engine, wherein the control advanced chemistry for liquid lubrication. What is needed is system provides independently controllable compression an adiabatic engine that overcomes these shortcomings. ratio and port timing, offering improved power density, 20 With rare exceptions, prior art reciprocating engines, efficiency, smoothness, compactness, torque and thermal adiabatic or otherwise, utilize crankshafts and connecting tolerance. The engine system herein has particular value in rods for the translation of reciprocating to rotary motion. aviation propulsion and other engine power applications This arrangement has been successfully applied to engines demanding maximum performance over wide load, speed comprised of from one to many cylinders laid out in various and altitude range. 25 configurations such as in a single line of cylinders parallel to BACKGROUND - DESCRIPTION OF PRIOR the crankshaft, banks of inline cylinders disposed around the ART crankshaft, radial cylinder dispositions and opposed-piston arrangements using one or more crankshafts geared together. Heretofore, internal combustion engines of the recipro A few crankshaft-type engines are known which have been cating type have been constructed of metals in forms best 30 constructed with parallel cylinders axially aligned in a barrel suited for their fabrication in such materials. However, due arrangement around the crankshaft or with inline cylinders to these materials prior art engines require supplemental transverse to the crankshaft. Both of these types rely on cooling and lubrication in order to function properly with additional auxiliary mechanisms such as gear trains, rocker adequate durability. These cooling and lubrication require arms, wobble plates, universal ball joints and the like for the ments further require provisions for fluid circulation and 35 translation of power. heat rejection accessories that can be burdensome in many Prior art engines that utilize crankshafts provide no applications. Aircraft applications of such engines are par mechanical advantage in the conversion of piston motion to ticularly sensitive to the installation of such accessories shaft torque. Furthermore, eccentricities in connecting rods because of the weight and aerodynamic drag associated with 40 and the like produce side loads in the reciprocating pistons their proper usage. In addition, the control of fluids in which give rise to friction and vibration. Another disadvan aircraft engines and their remote accessories such as radia tage of crankshaft-type engines is the complex load path that tors, oil coolers, pumps, oil sumps and the like is compli must be structurally accommodated in maintaining the cated because a fixed gravitational orientation can not be mechanical integrity of the engine. Typically, such loads are relied upon to disengage vapors and liquids and establish 45 passed through the cylinder walls which must also handle fluid levels. the stresses due to combustion. As a result, the cylinders A further disadvantage of most prior art engine construc must be constructed of materials having high tensile tions for aircraft applications is their dependence on strengths. Due to the complex forms of the structures increased output shaft speed as a means of reducing weight required, metallic materials constitute the only economic per unit of power output. Because propellers function effi 50 and durable means of construction, and then only if an ciently only with limited rotational speeds, most light abundance of cooling and lubrication is used. Furthermore, weight engines of the prior art type require speed-reducing crankshafts, by nature, must span the length of the engine.