What does Audi's internal circulation sign mean?
On the empty panel of Audi A4, there is a vehicle icon. The symbol of the circular arrow in the car is the symbol of the internal and external circulation of air.
Internal circulation open mode: the indicator light on the icon lights up for the first time and is set to enable internal circulation mode.
External circulation mode: click the indicator light on the icon again to close the external circulation mode, and leave it blank to open the external circulation mode.
Extended data
In the external circulation state, the air outside the car is sucked into the car by the fan, that is to say, the air passages inside and outside the car are circulating, and the air of the fan comes from outside the car. Even if the fan is not turned on, the airflow will still be sucked into the car during driving to replenish the fresh air in the car.
Sometimes when the fan is turned off, it will feel windy, just because the owner has set up an external circulation. When there is a traffic jam in the city, cars will be full of exhaust fumes, which is caused by the use of external circulation. The internal circulation state is that the air flow channels inside and outside the car are closed, and there is no air flow circulation without turning on the fan. Turn on the fan, and the inhaled airflow only comes from the car, forming an airflow circulation inside the car.
. The main purpose of internal circulation is to prevent external dust and harmful gases from entering the vehicle in time and effectively, such as blocking the harmful tail gas discharged by the preceding vehicle when driving through the smoke and odor area or when the vehicle is dense and compact. Another function is to keep warm.
Reference link: Baidu Encyclopedia-Internal and External Cycle of Automobile
Reference link: Audi official website A4L- Model Manual
What material is Audi's front axle made of?
In the 1920s, Audi, Hoshi, dkw and Roamer were four automobile companies, each responsible for different market segments. The use of assembly lines and modern machinery and equipment makes the production capacity rise rapidly, which further requires enterprises to increase sales while expanding the market, which requires a lot of costs; On the other hand, the price war triggered by foreign automobile manufacturers has caused great losses to automobile enterprises. German automobile industry finds it difficult to solve these financial problems and needs the support of bank loans. As a result, Saxony Bank met the loan demand of Rasmussen and laid the foundation for the expansion of Rasmussen Group. Since then, in order to safeguard its own interests in the automobile industry, Saxony Bank has established an automobile alliance based on four companies, with total assets of 654.38+04.5 million Deutsche Mark. There are four brands and their products of Audi, dkw, Hodge and Rover in the automobile alliance. However, in these very traditional companies, it will take a long time to form a unified group concept and make it work. At the 1933 German Auto Show, the automobile alliance first appeared in the form of a company, and its Audi front-wheel drive medium-sized car with the four-ring logo caused a sensation. However, due to the limited understanding of avant-garde technology in the market, its innovative function has not brought great sales. Therefore, the automobile alliance revised the design. 1938, Audi 920 sedan with modern interior and superior engine performance was put on the market. Its newly developed ohc engine has a power of 75 HP and a top speed of140 km/h. This kind of high-power and small-size car is deeply loved by people full of power and energy. Later, this front-wheel drive car was changed to rear-wheel drive, and the side chassis replaced the central square chassis, which has two types: 6-window type and 2-door 4-window type. The market demand of Audi 920 is great, and it sold a planned sales volume for one year soon after it went on the market. At that time, dkw mainly produced motorcycles. 1933 produced 8 motorcycles with engine capacities ranging from 175 ml to 600 ml. A year later, rt 100 went on the market. Its simple body and perfect combination of economy and power make it the standard of motorcycle production in the next few decades. Rt motorcycle has excellent performance and the price is 345 Deutsche Mark, which is one of the motorcycle models with the largest output. Class 200 motorcycles continue to consolidate the success of zschopau factory. Dkw took the lead in the motorcycle market and maintained this leading position until the appearance of nz series motorcycles in 1938. These fashionable motorcycles-with four-speed gearbox, pedal shifting device and rear suspension-are the best portrayal of dkw's leading position in the development of two-stroke motorcycles. Dkw compact cars are produced in Berlin-spandau (two-stroke engine, rear-wheel drive with charging pump v4) and Zwikau (two-cylinder two-stroke embedded engine, front-wheel drive) on Spandau Road in Berlin, Germany. All engines are produced in zschopau, while the front-wheel drive models assembled in Zweigao are equipped with wooden bodies produced by Berlin-Spandow Company. Reichsbahn, a German railway operator, transported these bodies to Zweishao at a price of 8 marks per body per day. Dkw front-wheel drive vehicles (design specifications f2, 4, 5, 7 and 8) have two grades: "Parliament Building KLASS" (600 cc engine, 18 horsepower) and "Mester KLASS" (700 cc engine, 20 horsepower). This beautiful steel convertible is called "the former Luxor". DKFront has always been the most popular and best-selling car in Germany. In the 1930s, 250,000 cars of this type were sold. Front-wheel drive gives it a lead. F9 is an improved model based on this model. It is equipped with a three-cylinder engine with 28 horsepower and a steel body. It is produced in Berlin-Spandau and Zwickau. This car was originally planned to be put into production at 1940, but due to the outbreak of World War II, the plan could not be realized. Huo company has been producing high-end cars in Zvikao for decades. Its engine is regarded as the industry benchmark. Because of its superior performance and exquisite appearance, many automobile manufacturers have followed suit. Horch 8 is gradually recognized as the best model. V8 engine developed by Fritz Federer went on sale in 1933. It was 3.0 liters at first, then increased to 3.5 liters and 3.8 liters, and the power increased from 70 horsepower to 92 horsepower. But compared with the 8-cylinder embedded 120 HP engine, the former is undoubtedly a "small" model. Because these two cars start with steel axle models, it is easy to have problems if the speed is too fast. 1935, Hoch car is equipped with independent front suspension, and de dion shaft (steel shaft and double universal joint mounted on the frame) is added at the rear. The 8-cylinder embedded engine 853 sports convertible launched in the same year is considered by many to be the most beautiful Hodge car ever. In the field of luxury cars, Hodge easily leads. 1937, luxury cars occupied 50% market share in the luxury car market of more than 4 liters. (Porsche) Professor Design. Later, on this basis, new modern suspension systems and models were developed. In 1933, the rear swing shaft is connected with the steel front axle and applied to w2 1 and w22, while in 1936, the independent front suspension is applied to w40, 45 and 50. Models named after three digits (such as W240, 250, etc.). ).) stands for the transition between 1935. Starting from 1937, the reliable and expensive ohv engine was replaced by the bypass valve engine with the same horsepower. The w24 (two-cylinder) and W24 (six-cylinder) models equipped with this engine were first launched at 1937. The engine is standardized, but the body has been greatly adjusted (steel rear axle and raised transverse spring). 1936, rover w5 1 made its debut. Since then, all the cars produced by the automobile alliance have more or less embodied the characteristics of this new model inspired by American models. From a certain point of view, automobile alliance is just a new term for some products with a long history at first, and its management still follows the original structure. Initially, the automobile alliance was established in DKW headquarters. 1936, the new office building of automobile alliance was built in Kenneth, marking the end of the era of independent research and development of automobiles in various places. A central design office and a central testing department were established in Kenneth, where new models were developed and tested, and then the prototypes and drawings of the cars were handed over to the production plants. The central organization, development and design office has been implementing the streamline concept from the beginning, which is based on the patent of Swiss aerodynamics expert paul jaray. The optimal aerodynamic characteristics are calculated by theoretical method for the first time, and experiments are carried out in wind tunnel. The head-on resistance coefficient of DKF9 car produced is surprisingly low, reaching cd = 0.42 (the predecessor of this car f8, the head-on resistance coefficient is 0.58), which became the German automobile manufacturing standard in the following decades. Due to the shortage of steel and rubber caused by the arms race and the high cost of wooden body decorated with leather (from the perspective of a large number of labor demand), the automobile alliance began to jointly develop plastic body in troisdorf, central and western Germany, and evaluated the strength of wood, steel and plastic through collision test for the first time in German automobile history. Simulated edge collision, lateral and forward rollover tests were carried out in the central laboratory of Chemnis. The technical department of the laboratory studied all factors related to materials, developed alloys and special production processes, and studied the technical applicability of all new designs. The technical department focuses on the future engine form, transmission development, vibration and noise research, and preparations for many complex tests, such as installing catapults in collision tests. The road test department is responsible for the feasibility test plan, series of tests and monitoring, as well as the comparison test with competitors. From 1933 to 1939, Audi automobile alliance has developed rapidly: the sales volume has steadily increased from 65 million German marks to 276 million German marks; The number of employees has increased from 8,000 to more than 23,000; The annual output of motorcycles increased from 6.5438+0.2 million to 59,000; The annual output of automobiles increased from 6.5438+0.7 million to 67,000. The automotive experts of the Alliance have obtained more than 3,000 patents in Germany and other countries, which shows their innovative ability. 1938, a quarter of buses were produced by the automobile alliance, and a third of motorcycles were produced by dkw. Automobile alliance has played a leading role in modern automobile innovation by virtue of its numerous technological development achievements, research achievements and innovative ideas. Just as the automobile alliance showed a strong development momentum, the outbreak of World War II ended the development of the automobile alliance itself, and the last civilian car was made in 1940. Since then, the automobile alliance has been forced to produce according to official instructions, and the vehicles it produces are only used for military purposes. The automobile alliance lasted 16 years, and the last three years were almost waiting for liquidation. In the six years before that, the war almost paralyzed its automobile business. All the innovations and rapid development of automobile alliance were completed in the first seven years. After the war, the production facilities of the automobile alliance were confiscated and demolished by the former Soviet occupation forces. In 1948, the company was deleted from the register of Camnis company. At the same time, many senior members of Auto Alliance came to Bavaria, West Germany, and Audi Auto Alliance was re-established here in Stat, Hingl.
What does Audi's internal circulation sign mean? What material is the front axle of Audi @20 19?