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104-777: The Lada / VAZ-2105 , 2104 and 2107 , collectively marketed as Lada Riva for right-hand drive models (in the United Kingdom, Australia and New Zealand), the Lada Nova in Germany, and by multiple other names and markets, are a series of compact sedans of the Zhiguli line-up ( Fiat 124 -based cars), built by Russian car manufacturer AvtoVAZ (formerly VAZ). Introduced in 1979 in the Soviet Union , and progressively introduced to Western European and global markets from

208-632: A "compact car" target that was larger than what has become known as the "light car" or the kei car . One of the first compact cars that met those requirements was the Toyota Publica with an air-cooled two-cylinder opposed engine, the Datsun 110 series , and the Mitsubishi 500 . The Publica and the Mitsubishi 500 were essentially "kei cars" with engines larger than regulations permitted at

312-709: A 21-piece toolkit. However, its spartan interiors and aging design meant that it was never aimed at buyers of market leaders' similar-sized but more expensive products, such as the Ford Sierra , Vauxhall Cavalier and Austin Montego . Nonetheless, the Riva was still selling well in the United Kingdom and many other Western markets in the early 1990s, but the next few years saw a raft of new models come from budget competitors such as Daewoo , Hyundai , Kia and Proton , pushing Riva sales into terminal decline. This, combined with

416-405: A Wankel rotary engine, the chamber volume V k {\displaystyle V_{k}} is equivalent to the product of the rotor surface A k {\displaystyle A_{k}} and the rotor path s {\displaystyle s} . The rotor surface A k {\displaystyle A_{k}} is given by the rotor tips' path across

520-400: A Wankel rotary engine, the eccentric shaft must make three full rotations (1080°) per combustion chamber to complete all four phases of a four-stroke engine. Since a Wankel rotary engine has three combustion chambers, all four phases of a four-stroke engine are completed within one full rotation of the eccentric shaft (360°), and one power pulse is produced at each revolution of the shaft. This

624-399: A boundary layer from overheating working parts. The University of Florida proposed the use of heat pipes in an air-cooled Wankel to overcome this uneven heating of the block housing. Pre-heating of certain housing sections with exhaust gas improved performance and fuel economy, also reducing wear and emissions. The boundary layer shields and the oil film act as thermal insulation, leading to

728-437: A displacement of 996 cm (61 in ), a rated power of 40 kW (54 hp) at 6,000   rpm and a BMEP of 1 MPa (145 lbf/in ). The Wankel engine has a spinning eccentric power take-off shaft, with a rotary piston riding on eccentrics on the shaft in a hula-hoop fashion. The Wankel is a 2:3 type of rotary engine, i.e., its housing's inner side resembles a two lobes oval-like epitrochoid (equivalent to

832-406: A fresh air supply to the exhaust port. It also proved that a Reed-valve in the intake port or ducts improved the low rpm and partial load performance of Wankel engines, by preventing blow-back of exhaust gas into the intake port and ducts, and reducing the misfire-inducing high EGR, at the cost of a slight loss of power at top rpm. Elasticity is improved with a greater rotor eccentricity, analogous to

936-462: A frontal crash test conducted by the modern Russian ARCAP safety assessment program, and was awarded zero stars out of four. The reviewers noted that the result of the test was easily predictable and couldn't be positive, as they were dealing with an old car having an outdated construction of the body and designed at the time when safety tests were different from those of 2001. In 2002 Za Rulyom magazine performed crash tests on two Lada 21053 models,

1040-439: A glow-plug for the leading site spark plug improved low rpm, part load, specific fuel consumption by 7%, and emissions and idle. A later alternative solution to spark plug boss cooling was provided with a variable coolant velocity scheme for water-cooled rotaries, which has had widespread use, being patented by Curtiss-Wright, with the last-listed for better air-cooled engine spark plug boss cooling. These approaches did not require

1144-431: A high incidence of sealing loss, both between the rotor and the housing and also between the various pieces making up the housing. Also, in earlier model Wankel engines, carbon particles could become trapped between the seal and the casing, jamming the engine and requiring a partial rebuild. It was common for very early Mazda engines to require rebuilding after 50,000 miles (80,000 km). Further sealing problems arose from

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1248-441: A high-conductivity copper insert, but did not preclude its use. Ford tested a Wankel engine with the plugs placed in the side plates, instead of the usual placement in the housing working surface ( CA 1036073   , 1978). Wankel engines are capable of high-speed operation, meaning they do not necessarily need to produce high torque to produce high power. The positioning of the intake port and intake port closing greatly affect

1352-525: A license plate number beginning with "5". In the past, the small size category has received tax benefits stipulated by the Japanese government regulations , such as those in the 1951 Road Vehicle Act . In 1955, the Japanese Ministry of International Trade and Industry set forth a goal to all Japanese makers at that time to create what was called a "national car". The concept stipulated that

1456-423: A longer stroke in a reciprocating engine. Wankel engines operate better with a low-pressure exhaust system. Higher exhaust back pressure reduces mean effective pressure, more severely in peripheral intake port engines. The Mazda RX-8 Renesis engine improved performance by doubling the exhaust port area relative to earlier designs, and there have been studies of the effect of intake and exhaust piping configuration on

1560-412: A low temperature of the lubricating film (approximate maximum 200 °C or 390 °F on a water-cooled Wankel engine). This gives a more constant surface temperature. The temperature around the spark plug is about the same as in the combustion chamber of a reciprocating engine. With circumferential or axial flow cooling, the temperature difference remains tolerable. Problems arose during research in

1664-406: A more steady idle, because it helps to prevent blow-back of burned gases into the intake ducts, which cause "misfirings" caused by alternating cycles where the mixture ignites and fails to ignite. Peripheral porting (PP) gives the best mean effective pressure throughout the rpm range, but PP was also linked to worse idle stability and part-load performance. Early work by Toyota led to the addition of

1768-537: A new car from 2002 and a used one from 1994. The magazine's experts noted that the newer model complied with UNECE car safety standards 12-03 and 33, but the older and used one failed the latter standard. The story also expressed doubt that the 2002 model could meet the stricter safety requirements that would be imposed in October of the same year. In the 2010s, the sales of the Lada Classics remained strong in

1872-782: A new market segment and the U.S. automobile industry soon adopted the "compact" term. Several competitors to the Nash Rambler arose from the ranks of America's other independent automakers, although none enjoyed the long-term success of the Rambler. Other early compact cars included the Kaiser-Frazer Henry J (also re-badged as the Allstate ), the Willys Aero and the Hudson Jet . In 1954, 64,500 cars sold in

1976-489: A peritrochoid),. In contrast, its rotary piston has a three vertices trochoid shape (similar to a Reuleaux triangle ). Thus, the Wankel engine's rotor constantly forms three moving working chambers. The Wankel engine's basic geometry is depicted in figure 7. Seals at the rotor's apices seal against the housing's periphery. The rotor moves in its rotating motion guided by gears and the eccentric output shaft, not being guided by

2080-498: A power output of 13.5 PS (10 kW) at 12,000   rpm. In 1954, NSU agreed to develop a rotary internal combustion engine with Felix Wankel, based upon Wankel's supercharger design for their motorcycle engines. Since Wankel was known as a "difficult colleague", the development work for the DKM was carried out at Wankel's private Lindau design bureau. According to John B. Hege, Wankel received help from his friend Ernst Höppner, who

2184-478: A result of the poor efficiency, a Wankel engine with peripheral exhaust porting has a larger amount of unburnt hydrocarbons (HC) released into the exhaust. The exhaust is, however, relatively low in nitrogen oxide (NOx) emissions, because the combustion is slow, and temperatures are lower than in other engines, and also because of the Wankel engine's good exhaust gas recirculation (EGR) behavior. Carbon monoxide (CO) emissions of Wankel and Otto engines are about

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2288-413: A rotary compressor as a supercharger for NSU's motorcycle engines. Wankel conceived the design of a triangular rotor in the compressor. With the assistance of Prof. Othmar Baier  [ de ] from Stuttgart University of Applied Sciences, the concept was defined mathematically. The supercharger he designed was used for one of NSU's 50 cm one-cylinder two-stroke engines. The engine produced

2392-547: A single "Klassika" ("Classic") family along with older models such as the VAZ-2101. They are popularly known as Pyatyorka ("the five"), Chetvyorka ("the four") and Semyorka ("the seven"). Mechanically, the car is virtually identical to the first-generation VAZ-2101, featuring the Fiat-derived manual transmissions , coil spring suspension all round, and aluminium alloy drum brakes with cast iron brake shoes on

2496-498: A single-rotor Wankel engine produces the same average power as a V h {\displaystyle V_{h}} single-cylinder two-stroke engine , with the same average torque, with the shaft running at the same speed, operating the Otto cycles at triple the frequency. Richard Franz Ansdale, Wolf-Dieter Bensinger and Felix Wankel based their analogy on the number of cumulative expansion strokes per shaft revolution. In

2600-456: A thermal reactor or catalyst converter may be used to reduce hydrocarbon and carbon monoxide from the exhaust. Mazda uses a dual ignition system with two spark plugs per chamber. This increases the power output and at the same time reduces HC emissions. At the same time, HC emissions can be lowered by reducing the pre-ignition of the T leading plug relative to the L trailing plug. This leads to internal afterburning and reduces HC emissions. On

2704-425: A thin dimensional galvanized chrome layer. This allowed Mazda to return to the 3mm and later even 2mm thick metal apex seals. Another early problem was the build-up of cracks in the stator surface near the plug hole, which was eliminated by installing the spark plugs in a separate metal insert/ copper sleeve in the housing instead of a plug being screwed directly into the block housing. Toyota found that substituting

2808-614: A trial basis 40-octane gasoline was produced by BV Aral, which was used in the Wankel DKM54 test engine with a compression ratio of 8:1; it ran without complaint. This upset the petrochemical industry in Europe, which had invested considerable sums of money in new plants for the production of higher quality gasoline. Direct injection stratified charge engines can be operated with fuels with particularly low octane numbers. Such as diesel fuel, which only has an octane number of ~25. As

2912-428: Is described in the thermodynamic disadvantages section , the early Wankel engines had poor fuel economy. This is caused by the Wankel engine's design of combustion chamber shape and huge surface area. The Wankel engine's design is, on the other hand, much less prone to engine knocking, which allows using low- octane fuels without reducing compression. NSU tested low octane gasoline at the suggestion of Felix Wankel. On

3016-440: Is different from a four-stroke piston engine, which needs to make two full rotations per combustion chamber to complete all four phases of a four-stroke engine. Thus, in a Wankel rotary engine, according to Bensinger, displacement ( V h {\displaystyle V_{h}} ) is: If power is to be derived from BMEP, the four-stroke engine formula applies: Eugen Wilhelm Huber, and Karl-Heinz Küttner counted all

3120-526: Is similar to the Otto operating principle; the Diesel operating principle with its compression ignition cannot be used in a practical Wankel engine. Therefore, Wankel engines typically have a high-voltage spark ignition system. In a Wankel engine, one side of the triangular rotor completes the four-stage Otto cycle of intake, compression, expansion, and exhaust each revolution of the rotor (equivalent to three shaft revolutions, see Figure 8.). The shape of

3224-397: Is the number of chambers considered for each rotor and i {\displaystyle i} the number of rotors, then the total displacement is: If p m e {\displaystyle p_{me}} is the mean effective pressure , N {\displaystyle N} the shaft rotational speed and n c {\displaystyle n_{c}}

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3328-696: The Kreiskolbenmotor (KKM, "circuitous piston engine"), designed by Hanns-Dieter Paschke (see Figure 3.), of which only the latter has left the prototype stage. Thus, all production Wankel engines are of the KKM type. Felix Wankel designed a rotary compressor in the 1920s, and received his first patent for a rotary type of engine in 1934. He realized that the triangular rotor of the rotary compressor could have intake and exhaust ports added producing an internal combustion engine. Eventually, in 1951, Wankel began working at German firm NSU Motorenwerke to design

3432-686: The Recession of 1958 , the only exception to the sales decline was American Motors with its compact, economy-oriented Ramblers that saw high demand among cautious consumers. By 1959, sales of small imported cars also increased to 14% of the U.S. passenger car market, as consumers turned to compact cars. By this time, smaller cars appealed to people with a college education and a higher income whose families were buying more than one car. Customers expected compact cars to provide improved fuel economy compared to full-sized cars while maintaining headroom, legroom, and plenty of trunk space. Between 1958 and 1960,

3536-472: The "small Ford" and produced the Ford Vedette . The first U.S.-produced postwar compact car was the 1950 Nash Rambler . It was built on a 100-inch (2,540 mm) wheelbase, which was nonetheless still a large car by contemporary European standards. The term "compact" was coined by a Nash executive as a euphemism for small cars with a wheelbase of 110 inches (2,794 mm) or less. It established

3640-418: The 1,452 cc (88.6 cu in) chain-driven OHC engine coming over from the original Lada 1500 ( VAZ-2103 ), while others had a later 1,569 cc (95.7 cu in) 1,6L VAZ-2106 /21067 engine. Another change was made to the engine in 1992, when single point fuel injection and catalytic converters were specified to keep up with emissions legislation. The 2107 was announced in 1982, offered as

3744-594: The 1950s and 1960s. For a while, engineers were faced with what they called "chatter marks" and "devil's scratch" in the inner epitrochoid surface, resulting in chipping of the chrome coating of the trochoidal surfaces. They discovered that the cause was the apex seals reaching a resonating vibration, and the problem was solved by reducing the thickness and weight of the apex seals as well as using more suitable materials. Scratches disappeared after introducing more compatible materials for seals and housing coatings. Yamamoto experimentally lightened apex seals with holes. Now, weight

3848-809: The 1980s that American cars were being downsized to truly international dimensions. In the 1985 model year, compact cars classified by the EPA included Ford's Escort and Tempo as well as the Chevrolet Cavalier. For the 2019 model year, the best sellers were the Toyota Corolla and Honda Civic. In Japan, vehicles that are larger than kei cars , but with dimensions smaller than 4,700 mm (185.0 in) long, 1,700 mm (66.9 in) wide, 2,000 mm (78.7 in) high and with engines at or under 2,000 cc (120 cu in) are classified as "small size" cars. Small-size cars are identified by

3952-608: The 21041 with 1,198 cc (73.1 cu in); and the 21043 with 1,452 cc (88.6 cu in) (VAZ-2103) engine. Export sales proved to be very good in Eastern Europe. In the West, Rivas had limited presence in such countries as the United Kingdom, the Netherlands, New Zealand (where it served as a taxi), and Canada. In Finland, they had much larger sales due to the fact that Finland had closer economic ties with

4056-837: The AvtoVAZ factory in the Russian Federation and was sold as the Lada Classic . It was one of the cheapest automobiles available in the Russian market and remains the most popular second-hand car in Russia even after its production ceased. In 2002, production of the wagon model was taken over by Izh , before assembly was also started at the Bogdan Group 's LuAZ plant, and later in Cherkasy , Ukraine . The 2107 model

4160-406: The DKM into what would later be known as the KKM (see figure 5.). The KKM proved to be a much more practical engine, as it has easily accessible spark plugs, a simpler cooling design, and a conventional power take-off shaft. Wankel disliked Froede's KKM engine because of its inner rotor's eccentric motion, which was not a pure circular motion, as Wankel had intended. He remarked that his "race horse"

4264-594: The Honda City, Toyota Yaris, Toyota Corolla Altis 1.6, and the Changan Alsvin. Wankel engine The Wankel engine ( /ˈvaŋkəl̩/ , VUN -kell ) is a type of internal combustion engine using an eccentric rotary design to convert pressure into rotating motion. The concept was proven by German engineer Felix Wankel , followed by a commercially feasible engine designed by German engineer Hanns-Dieter Paschke. The Wankel engine's rotor, which creates

Lada Riva - Misplaced Pages Continue

4368-408: The KKM engine on 13 June 1961. Throughout the design phase of the KKM, Froede's engineering team had to solve problems such as repeated bearing seizures, the oil flow inside the engine, and the engine cooling. The first fully functioning KKM engine, the KKM 125, weighing in at only 17 kg (37.5 lb) displaced 125 cm and produced 26 PS (19 kW) at 11,000   rpm. Its first run

4472-519: The Riva's origins are older: it is a modernised and restyled version of the original Lada type VAZ-2101 Zhiguli saloon, which was introduced in 1970 as a modified license copy of the Fiat 124 . VAZ began development work on the facelift version as early as 1975, and the first prototypes were built in 1977, although it would not be until 1983 – three years after its release in the Soviet Union – that

4576-560: The Soviet Union. Canada was the only market to offer whitewall tires. Canadian 2107s were "briefly sold as the Dennis Signet", after the importer, Peter Dennis Motor Corporation. Canadian sales, along with several European markets, ended on 4 July 1997. Tightening safety and emissions legislation combined with the economic instability in the former Soviet Union during the 1990s led to the Riva being withdrawn from most Western European markets by 1997, although it remained in production at

4680-407: The U.S. were imports or small American cars, out of a total market of five million cars. Market research indicated that five percent of those surveyed said they would consider a small car, suggesting a potential market size of 275,000 cars. By 1955, the Nash Rambler that began as a convertible model became a success and was now available in station wagon , hardtop , and sedan body styles. During

4784-447: The Wankel engine has a lower moment of inertia and less excess torque area due to its more uniform torque delivery. For example, a two-rotor Wankel engine runs more than twice as smoothly as a four-cylinder piston engine. The eccentric output shaft of a Wankel engine also does not have the stress-related contours of a reciprocating piston engine's crankshaft. The maximum revolutions of a Wankel engine are thus mainly limited by tooth load on

4888-511: The Wankel engine suited for applications such as chainsaws , auxiliary power units (APUs), loitering munitions , aircraft , jet skis , snowmobiles , and range extenders in cars . The Wankel engine was also used to power motorcycles and racing cars . The Wankel engine is a type of rotary piston engine and exists in two primary forms, the Drehkolbenmotor (DKM, "rotary piston engine"), designed by Felix Wankel (see Figure 2.) and

4992-613: The average torque, with the shaft running at 2/3 the speed, operating the Otto cycles at the same frequency: Applying a 2/3 gear set to the output shaft of the three-cylinder (or a 3/2 one to the Wankel), the two are analogous from the thermodynamic and mechanical output point of view, as pointed out by Huber. NSU licensed the Wankel engine design to companies worldwide, in various forms, with many companies implementing continual improvements. In his 1973 book Rotationskolben-Verbrennungsmotoren , German engineer Wolf-Dieter Bensinger describes

5096-422: The axially closer side housings in the cooler intake lobe areas was dealt with by using an axial rotor pilot radially inboard of the oils seals, plus improved inertia oil cooling of the rotor interior (C-W US 3261542   , C. Jones, 5/8/63, US 3176915   , M. Bentele, C. Jones. A.H. Raye. 7/2/62), and slightly "crowned" apex seals (different height in the center and in the extremes of seal). As

5200-783: The beginning of a downsizing of all vehicles so that cars such as the AMC Concord and the Ford Fairmont that replaced the compacts were re-classified as mid-size, while cars inheriting the size of the Ford Pinto and Chevrolet Vega (such as the Ford Escort and Chevrolet Cavalier ) became classified as compact cars. Even after the reclassification, mid-size American cars were still far larger than mid-size cars from other countries and were more similar in size to cars classified as "large cars" in Europe. It would not be until

5304-551: The car was made available in Western European markets, and like its predecessors - aimed squarely at the budget end of the market. The Riva itself is officially designated – and known in the home market – as VAZ-2105 (base saloon [sedan]), VAZ-2104 (station wagon), and VAZ-2107 (deluxe saloon identified by the large chromed grille). In Russia, VAZ-2105, VAZ-2104, and VAZ-2107 are considered to be different cars rather than variants but nonetheless all of them are part of

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5408-579: The car's native Russia and some of the former Eastern Bloc nations. However, production of the 2105 ceased at AvtoVAZ's Togliatti plant at the end of 2010 after a 30-year production run and nearly 3,000,000 units, with production of the other variants being fully moved to the IzhAvto plant near Izhevsk . The 2107 made the transition to the IzhAvto plant in August 2011, thus marking the end of production of

5512-588: The catalysts were quickly destroyed as a result and most cars failed their first MOT test (at three years old) as a result. Despite Lada's withdrawal in 1997 from the British market, most of the surviving Rivas on UK roads were not scrapped; rather the vast majority were re-exported back to Russia due to a shortage of used examples in their homeland and the export specification was considered superior to those that were available domestically. Even in 2021, many ex-UK right hand drive Rivas are still operating in Russia and

5616-407: The chambers, since each one operates its own thermodynamic cycle. So y = 3 {\displaystyle y=3} and n c = 3 {\displaystyle n_{c}=3} : With these values, a single-rotor Wankel engine produces the same average power as a V h {\displaystyle V_{h}} three-cylinder four-stroke engine, with 3/2 of

5720-582: The combined passenger and cargo volume, compact cars are defined as having an interior volume index of 100–109 cu ft (2.8–3.1 m ). The beginnings of U.S. production of compact cars were the late 1940s prototypes of economy cars, including the Chevrolet Cadet and the Ford Light Car. Neither car reached production in the U.S., however Ford SAF in France bought the plans of

5824-559: The early 1980s, under the Lada brand, they were sold as saloons (2105 and 2107), and station wagon (2104) versions. Today they are generally referred to as the Lada Classic series, being derived from the original Fiat 124 platform which has been the now-iconic mainstay of the AvtoVAZ lineup since the company's foundation in the late 1960s. Russian production at the company's main plant at Togliatti ended in September 2012. Along with

5928-448: The early days, unique, dedicated production machines had to be built for different housing dimensional arrangements. However, patented designs such as U.S. patent 3,824,746 , G. J. Watt, 1974, for a "Wankel Engine Cylinder Generating Machine", U.S. patent 3,916,738 , "Apparatus for machining and/or treatment of trochoidal surfaces" and U.S. patent 3,964,367 , "Device for machining trochoidal inner walls", and others, solved

6032-517: The economic hardships and much-needed investment to adapt cars to stricter European Union emissions requirements not being available, resulted in the decision to withdraw Lada from the UK (and some other European markets) and Canada on 4 July 1997. They had cheaply tried to produce catalytic converter equipped cars (EU mandated from 1992) using carburettors, when all other car makers changed to fuel injection to more accurately control fuel/air ratios. However

6136-416: The engine's torque production. Early closing of the intake port increases low-end torque, but reduces high-end torque (and thus power). In contrast, late closing of the intake port reduces low-end torque while increasing torque at high engine speeds, thus resulting in more power at higher engine speeds. A peripheral intake port gives the highest mean effective pressure ; however, side intake porting produces

6240-431: The engine. While this puts great demands on the materials used, the simplicity of the Wankel makes it easier to use alternative materials, such as exotic alloys and ceramics . A commonplace method is, for engine housings made of aluminum, to use a spurted molybdenum layer on the engine housing for the combustion chamber area, and a spurted steel layer elsewhere. Engine housings cast from iron can be induction-brazed to make

6344-421: The experience gained, from carbon alloys, to steel, ferritic stainless , Ferro-TiC, and other materials. The combination of housing plating and the apex and side seal materials was determined experimentally, to obtain the best duration of both seals and housing cover. For the shaft, steel alloys with little deformation on load are preferred, the use of Maraging steel has been proposed for this. Leaded petrol fuel

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6448-449: The external chamber. The rotor does not make contact with the external engine housing. The force of expanded gas pressure on the rotor exerts pressure on the center of the eccentric part of the output shaft. All practical Wankel engines are four-cycle (i.e., four-stroke) engines. In theory, two-cycle engines are possible, but they are impractical because the intake gas and the exhaust gas cannot be properly separated. The operating principle

6552-463: The factor that controls the amount of unburnt hydrocarbons in the exhaust is the rotor surface temperature, with higher temperatures resulting in fewer hydrocarbons in the exhaust. Curtiss-Wright widened the rotor, keeping the rest of engine's architecture unchanged, thus reducing friction losses and increasing displacement and power output. The limiting factor for this widening was mechanical, especially shaft deflection at high rotative speeds. Quenching

6656-404: The farthest, and a {\displaystyle a} as the shortest parallel transfer of the rotor and the inner housing and assuming that R 1 = R + a {\displaystyle R_{1}=R+a} and R 2 = R + a ′ {\displaystyle R_{2}=R+a'} . Then, Including the parallel transfers of the rotor and

6760-529: The following licensees, in chronological order, which is confirmed by John B. Hege: In 1961, the Soviet research organizations of NATI, NAMI, and VNIImotoprom began developing a Wankel engine. Eventually, in 1974, development was transferred to a special design bureau at the AvtoVAZ plant. John B. Hege argues that no license was issued to any Soviet car manufacturer. Felix Wankel managed to overcome most of

6864-674: The former Soviet states. The car was also sold in New Zealand , where it was distributed by the New Zealand Dairy Board . The Dairy Board received the cars in lieu of cash payments for deliveries of mutton and butter to the Soviet Union. The last such trade was carried out in 1990. Estate edition Pickup Edition Model variants included the Riva Signet, Riva 1200, Riva 1300, Riva 1500, and Riva 1600, with trim levels "E" and "L". A Turbo charged model Lada 2107 Turbo

6968-569: The four engines built has been on static display at the Deutsches Museum Bonn (see figure. 2). Due to its complicated design with a stationary center shaft, the DKM engine was impractical. Wolf-Dieter Bensinger explicitly mentions that proper engine cooling cannot be achieved in a DKM engine, and argues that this is the reason why the DKM design had to be abandoned. NSU development chief engineer Walter Froede solved this problem by using Hanns-Dieter Paschke's design and converting

7072-423: The four-stroke reciprocating piston engine. The thermal inefficiency has restricted the engine to limited use since its introduction in the 1960s. However, many disadvantages have mainly been overcome over the succeeding decades as the production of road-going vehicles progressed. The advantages of compact design, smoothness, lower weight, and fewer parts over the reciprocating piston internal combustion engines make

7176-449: The inner housing provides sufficient accuracy for determining chamber volume. Different approaches have been used over time to evaluate the total displacement of a Wankel engine in relation to a reciprocating engine: considering only one, two, or all three chambers. Part of this dispute was because of Europe vehicle taxation being dependent on engine displacement, as reported by Karl Ludvigsen . If y {\displaystyle y}

7280-423: The luxury version (and the most expensive), with improved interior (including front headrests), a new instrument panel, and a chrome grille; it came with either 1,294 cc (79.0 cu in) (21072) or 1,570 cc (96 cu in) (21074) engines. (The 21079 was a Wankel engined version.) The first 2104 station wagon appeared in 1984, in three models: the 2104 with 1,294 cc (79.0 cu in);

7384-533: The major U.S. car manufacturers made a push toward compact cars, resulting in the introduction of the Studebaker Lark , Chevrolet Corvair , Ford Falcon , and Plymouth Valiant . These models also gave rise to compact vans built on the compact car platforms, such as the Studebaker Zip Van, Chevrolet Corvair Greenbrier , Ford Econoline , and Dodge A100 . During the 1960s, compacts were

7488-414: The material suited for withstanding combustion heat stress. Among the alloys cited for Wankel housing use are A-132, Inconel 625, and 356 treated to T6 hardness. Several materials have been used for plating the housing working surface, Nikasil being one. Citroën, Daimler-Benz, Ford, A P Grazen, and others applied for patents in this field. For the apex seals, the choice of materials has evolved along with

7592-430: The number of shaft revolutions needed to complete a cycle ( N / n c {\displaystyle N/n_{c}} is the frequency of the thermodynamic cycle), then the total power output is: Kenichi Yamamoto and Walter G. Froede placed y = 1 {\displaystyle y=1} and n c = 1 {\displaystyle n_{c}=1} : With these values,

7696-578: The older VAZ-2101/2102/2106 ended soon after the Riva's introduction, although they remained available in the Soviet Union and much of the old Eastern Bloc for several years afterwards. In a review of the new economy car , the British automobile magazine Autocar noted its low price of only £3,158 (£10,736.82 in 2020), improved road performance and an "impressive list of standard equipment", which included "height-adjustable headlamps, internally adjustable driver's door mirror, velour-covered seats, heated rear window, illumination lights for bonnet and boot", and

7800-517: The original Fiat 124 derived models at Togliatti after a 41-year production run and over 14 million units. In September 2012, the history of the sedan model in Russia was over, when the last 2104 came off the IzhAvto assembly lines. The last unit of the Lada Classic series, a 2104 model, was produced by IzhAvto on 17 September 2012. Starting from the same month, production at the Izhevsk factory

7904-877: The other Fiat 124 derivatives, it is the world's third best selling, single generation automobile platform , after the Volkswagen Beetle and the Ford Model T , and one of the longest production run platforms alongside the Volkswagen Beetle, the Hindustan Ambassador , the Volkswagen (Type 2) Bus , the Toyota 70 Series , and the Mercedes-Benz G-Class . Although introduced in 1979 and first produced in quantity in 1980,

8008-506: The other hand, the same ignition timing of L and T leads to a higher energy conversion. Hydrocarbons adhering to the combustion chamber wall are expelled into the exhaust at the peripheral outlet. Mazda used 3 spark plugs in their R26B engine per chamber. The third spark plug ignites the mixture in the trailing side before the squish is generated, causing the mixture to burn completely and, also speeding up flame propagation, which improves fuel consumption. According to Curtiss-Wright research,

8112-462: The outer rotor's shape, thus proving impractical. According to Mazda Motors engineers and historians, four units of the DKM engine were built; the design is described to have a displacement V h of 250 cm (equivalent to a working chamber volume V k of 125 cm ). The fourth unit built is said to have received several design changes, and eventually produced 29 PS (21 kW) at 17,000 rpm; it could reach speeds up to 22,000 rpm. One of

8216-699: The passenger and cargo compartments were introduced in the late 1970s. In the early 1970s, the domestic automakers introduced even smaller subcompact cars that included the AMC Gremlin , Chevrolet Vega , and Ford Pinto . In 1973, the Energy Crisis started, which made small fuel-efficient cars more desirable, and the North American driver began exchanging their large cars for the smaller, imported compacts that cost less to fill up and were inexpensive to maintain. The 1977 model year marked

8320-482: The performance of Wankel engines. Side intake ports (as used in Mazda's Renesis engine) were first proposed by Hanns-Dieter Paschke in the late 1950s. Paschke predicted that precisely calculated intake ports and intake manifolds could make a side port engine as powerful as a PP engine. As formerly described, the Wankel engine is affected by unequal thermal expansion due to the four cycles taking place in fixed places of

8424-640: The popular Volkswagen Beetle . Compact cars were also the basis for a new small car segment that became known as the pony car , named after the Ford Mustang , which was built on the Falcon chassis. At that time, there was a distinct difference in size between compact and full-size models. Early definitions of vehicle size class were based on wheelbase, with models under 111 inches as compact, 111 to 118 inches intermediate, and over 118 inches as full size, at least until EPA classes based on interior volume of

8528-463: The problem. Wankel engines have a problem not found in reciprocating piston four-stroke engines in that the block housing has intake, compression, combustion, and exhaust occurring at fixed locations around the housing. This causes a very uneven thermal load on the rotor housing. In contrast, four-stroke reciprocating engines perform these four strokes in one chamber, so that extremes of "freezing" intake and "flaming" exhaust are averaged and shielded by

8632-421: The problems that made prior attempts to perfect the rotary engines fail, by developing a configuration with vane seals having a tip radius equal to the amount of "oversize" of the rotor housing form, relative to the theoretical epitrochoid, to minimize radial apex seal motion plus introducing a cylindrical gas-loaded apex pin which abutted all sealing elements to seal around the three planes at each rotor apex. In

8736-423: The rear wheels. The smaller-engined variant, the 66  PS (48  kW ; 65  hp ) 1,294 cc (79.0 cu in) version (VAZ-2105) had a revamp of its inline four-cylinder compared to the original VAZ-2101 (Lada 1200). The old OHC design had its camshaft driven by chain, while the new one had a toothed belt drive. Some modifications of the Riva's larger-engined version (VAZ-2107) carried on with

8840-402: The rotor between the fixed apexes is to minimize the volume of the geometric combustion chamber and maximize the compression ratio , respectively. As the rotor has three sides, this gives three power pulses per revolution of the rotor. Wankel engines have a much lower degree of irregularity relative to a reciprocating piston engine, making the Wankel engine run much smoother. This is because

8944-410: The rotor housing and determined by the generating radius R {\displaystyle R} , the rotor width B {\displaystyle B} , and the parallel transfers of the rotor and the inner housing a {\displaystyle a} . Since the rotor has a trochoid ("triangular") shape, the sine of 60 degrees describes the interval at which the rotors get closest to

9048-443: The rotor housing. Therefore, The rotor path s {\displaystyle s} may be integrated via the eccentricity e {\displaystyle e} as follows: Therefore, For convenience, a {\displaystyle a} may be omitted because it is difficult to determine and small: A different approach to this is introducing a ′ {\displaystyle a'} as

9152-407: The same. The Wankel engine has a significantly higher (Δt K >100 K) exhaust gas temperature than an Otto engine, especially under low and medium load conditions. This is because of the higher combustion frequency and slower combustion. Exhaust gas temperatures can exceed 1300 K under high load at engine speeds of 6000 rpm . To improve the exhaust gas behavior of the Wankel engine,

9256-553: The smallest class of North American cars, but they had evolved into only slightly smaller versions of the 6-cylinder or V8-powered six-passenger sedan. They were much larger than compacts (and sometimes even mid-sizers) by European manufacturers, which were typically five-passenger four-cylinder engine cars. Nevertheless, advertising and road tests for the Ford Maverick and the Rambler American made comparisons with

9360-519: The synchronizing gears. Hardened steel gears are used for extended operation above 7,000 or 8,000   rpm. In practice, automotive Wankel engines are not operated at much higher output shaft speeds than reciprocating piston engines of similar output power. Wankel engines in auto racing are operated at speeds up to 10,000   rpm, but so are four-stroke reciprocating piston engines with relatively small displacement per cylinder. In aircraft, they are used conservatively, up to 6500 or 7500   rpm. In

9464-842: The time, while the Datsun was an all-new vehicle. These vehicles were followed by the Hino Contessa in 1961, the Isuzu Bellett , Daihatsu Compagno and Mazda Familia in 1963, the Mitsubishi Colt in 1965, and the Nissan Sunny , Subaru 1000 , and Toyota Corolla in 1966. Honda introduced its first four-door sedan in 1969, called the Honda 1300 . In North America, these cars were classified as subcompact cars . By 1970, Nissan released its first front-wheel-drive car which

9568-429: The turning motion, is similar in shape to a Reuleaux triangle , with the sides having less curvature. The rotor spins inside a figure-eight-like epitrochoidal housing around a fixed-toothed gearing. The midpoint of the rotor moves in a circle around the output shaft, rotating the shaft via a cam. In its basic gasoline fuelled form, the Wankel engine has lower thermal efficiency and higher exhaust emissions relative to

9672-512: The uneven thermal distribution within the housings causing distortion and loss of sealing and compression. This thermal distortion also caused uneven wear between the apex seal and the rotor housing, evident on higher mileage engines. The problem was exacerbated when the engine was stressed before reaching operating temperature . However, Mazda Wankel engines solved these initial problems. Current engines have nearly 100 seal-related parts. The problem of clearance for hot rotor apexes passing between

9776-399: The vehicle be able to maintain a maximum speed over 100 km/h (62 mph), weigh below 400 kg (882 lbs), fuel consumption at 30 km/L (85 mpg ‑imp ; 71 mpg ‑US ) or more, at an average speed of 60 km/h (37 mph) on a level road, and not require maintenance or significant service for at least 100,000 km (62,000 mi). This established

9880-542: Was a "brilliant engineer". The first working prototype, DKM 54 (see figure 2.), first ran on 1 February 1957, at the NSU research and development department Versuchsabteilung TX . It produced 21 PS (15 kW). Soon after that, a second prototype of the DKM was built. It had a working chamber volume V k of 125 cm and also produced 21 kW (29 PS) at 17,000   rpm. It could even reach speeds of up to 25,000   rpm. However, these engine speeds distorted

9984-456: Was found at a local Suzuki plant in Cairo to assemble the 2107 version of the Riva. As of 2006, production continued at Suzuki until 2015 with an additional model, the 2110 , being produced. In the early 1980s, when it was put into production, the car complied with UNECE car safety standards and GOST technical standards. In 2001, the 2107 version of the Riva scored 0 points out of 16 in

10088-456: Was identified as the main cause. Mazda then used aluminum-impregnated carbon apex seals in their early production engines. NSU used carbon antimony-impregnated apex seals against chrome. NSU developed ELNISIL coating to production maturity and returned to a metal sealing strip for the RO80. Mazda continued to use chrome, but provided the aluminum housing with a steel jacket, which was then coated with

10192-513: Was on 1 July 1958. In 1963, NSU produced the first series-production Wankel engine for a car, the KKM 502 (see Figure 6.). It was used in the NSU Spider sports car, of which about 2,000 were made. Despite its "teething troubles", the KKM ;502 was a powerful engine with decent potential, smooth operation, and low noise emissions at high engine speeds. It was a single-rotor PP engine with

10296-615: Was originally developed by Prince Motor Company which had merged with Nissan in 1966. This was introduced in 1970 as the Nissan Cherry . In 1972, the Honda Civic appeared with the CVCC engine that was able to meet California emission standards without the use of a catalytic converter . In Pakistan, the concept of compact cars is significant. The most common cars tend to be Kei cars . Popular compact cars in recent times are

10400-752: Was produced also at the ZAZ factory in Ukraine and at Suzuki 's factory in Egypt . In August 2011, Russian production of the 2107 was moved to Izh. After about thirty years of production, the 2105 was discontinued in 2010, followed by the 2104 and 2107 in 2012. The British market was opened with the 1300GL in 1983, and the 21051 (Riva 1200L) had the 1,198 cc (73.1 cu in). British sales were based heavily on low sales price and durability. In 1986, 20,000 Ladas were sold in Britain, 30,000 in 1988. British imports of

10504-604: Was replaced with the Lada Granta . However, as of 2014, the 2107 model was still in production in Egypt. Compact car In Japan, small size passenger vehicle is a registration category that sits between kei cars and regular cars, based on overall size and engine displacement limits. The United States Environmental Protection Agency (EPA) Fuel Economy Regulations for 1977 and Later Model Year (dated July 1996) includes definitions for classes of automobiles. Based on

10608-648: Was sold in Finland, this version was made by Finnish Lada importer. Small numbers of Lada rally cars were built with 150 PS (110 kW) Wankel engines , fitted with a pair of Weber DCOE twin-choke carburettors . In Egypt , the Amal Foreign Trade Company and Lada's parent company AvtoVAZ signed a joint venture agreement to assemble Ladas for the North African market in 2000. However, as they did not have their own factory, space

10712-573: Was the predominant type available in the first years of the Wankel engine's development. Lead is a solid lubricant, and leaded petrol is designed to reduce the wearing of seals and housings. The first engines had the oil supply calculated with consideration of petrol's lubricating qualities. As leaded petrol was being phased out, Wankel engines needed an increased mix of oil in the petrol to provide lubrication to critical engine parts. An SAE paper by David Garside extensively described Norton's choices of materials and cooling fins. Early engine designs had

10816-449: Was turned into a "plough horse". Wankel also complained that more stresses would be placed on the KKM's apex seals due to the eccentric hula-hoop motion of the rotor. NSU could not afford to finance developing both the DKM and the KKM, and eventually decided to drop the DKM in favor of the KKM, because the latter seemed to be the more practical design. Wankel obtained the US patent 2,988,065 on

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