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MOTOR ELECTRIC MOTOR Developed by a technology teacher of the highest category, Honorary Worker of Primary Vocational Education of the Russian Federation MBOU "Secondary School No. 7", Kaluga Gerasimov Vladislav Aleksandrov
What do these electrical appliances have in common?
COLLECTOR ELECTRIC MOTOR
HISTORY. The first collector electric motor was designed in Russia by the Russian scientist Jacobi Boris Semenovich in 1838. By the 70s of the 19th century, the electric motor had already been improved so much that it has survived in this form to this day.
Boris Semyonovich Jacobi
Purpose: Converting electrical energy into mechanical energy. Mechanical energy sets in motion the working parts of machines and mechanisms.
Principle of operation: Electric current from a source (batteries of galvanic cells) is fed into the winding through special sliding contacts - brushes. These are two elastic metal plates that are connected by conductors to the poles of the current source and pressed against the collector. When an electric current flows through the armature winding, the rotor begins to rotate under the influence of a magnet.
General arrangement of the electric motor 1-bearings, 2-back cover of the stator, 3-winding, 4-armature, 5-core, 6-armature winding, 7-collector, 8-front cover, 9-shaft, 10-impeller.
Smallest engines of this type... three-pole rotor with sleeve bearings; collector unit of two brushes - copper plates; two-pole stator made of permanent magnets... They are mainly used in children's toys (operating voltage 3-9 volts).
Powerful motors (tens of watts), as a rule, have: multi-pole rotor on rolling bearings; collector unit of four graphite brushes; four-pole permanent magnet stator. It is this design that most electric motors in modern cars(operating voltage 12 or 24 volts): drive of fans of cooling and ventilation systems, wipers, washer pumps.
Collector motor-wheel, 24 volts 230 watts.
Motors with a capacity of hundreds of watts Unlike the previous ones, they contain a four-pole stator made of electromagnets. The stator windings can be connected in several ways: in series with the rotor (the so-called sequential excitement), advantage: high maximum torque, disadvantage: high speed idle move that could damage the engine.
parallel to the rotor (parallel excitation) Advantage: greater speed stability when the load changes, disadvantage: lower maximum torque Some of the windings are parallel to the rotor, some in series (mixed excitation) to some extent combines the advantages of previous types, for example, automobile starters. separate power supply ( independent excitement) the characteristic is similar to parallel connection, however it can usually be adjusted.
Electric motor direct current parallel excitation
DC motor with series excitation
Methods for changing the frequency of rotation of the motor shaft By changing the magnitude of the stator excitation current. The higher the current in the stator, the higher the rotational speed of the motor shaft.
The advantages of electric motors. No harmful emissions during operation Do not require constant maintenance Can be installed in any place Work under vacuum conditions Do not use flammable substances (gasoline, diesel fuel) Ease of use
Failures in the operation of a collector electric motor Operating conditions and service life of motors in household machines are different. The reasons for their failure are also different. It was found that 85-95% fail to work due to damage to the insulation of the windings distributed as follows: 90% of turn-to-turn faults and 10% of damage and insulation breakdowns on the case. This is followed by bearing wear, deformation of the rotor or stator steel, and bending of the shaft.
The repair technological process includes the following basic operations:
Pre-repair tests External cleaning of dirt and dust Dismantling into assemblies and parts Removing windings Washing assemblies and parts Defecting assemblies and parts Repair and manufacturing of assemblies and parts Rotor assembly Production and laying of windings Drying and impregnation works Mechanical processing rotor in assembled form and its balancing Completing of assemblies and parts Assembling electric motors Tests after repair Exterior decoration
Summing up the lesson. What is an electric motor? In which devices are collector motors used? What parts does a collector motor consist of? What is the principle behind the operation of a collector motor?
"Heat machines" - Q1. C: \ Documents and Settings \ Director \ My Documents \ steam turbine.swf. Who built it and when? Engine internal combustion... 1770 Efficiency of ideal heat engine... Heater T1. " Younger brother"- a steam locomotive. The working medium can be steam or gas. Average speed of movement is 72 km / h. From 1775 to 1785 - 56 steam engines were built by the Watt firm.
"Railroad" - Road? Roads of China. Freight carts. Memorable kilometer-mark on the Kushelevka-Piskarevka railway section. Siege Leningrad. Highway... A covered wagon is sometimes called a wagon. Metro station. The stroller is a lightweight small carriage. The road is layered, straight and paved. Serpentine - A winding mountain road.
"Making a car" - Objectives of my research: Prepared by a student of the 11th grade of the Municipal Educational Institution "Sosh village of Slantsevy Rudnik" Dima Matrosov. Offer independent research to students. The history of the creation of cars. A car is a device with a motor for the movement of passengers or goods. I believe that the car is an important invention in human life.
"Railway transport" - CEN, CENELEC. "On the safety of high-speed railway transport". Other organizations. Rules and regulations of the federal executive authorities. Oszhd. Speech by VA GAPANOVICH, Senior Vice President of Russian Railways. Interstate Technical Committee for Standardization No. 524 "Railway Transport".
"Outboard motors" - STATIONARY GASOLINE ENGINE with Z-drive. Reducer / reverse. Engine. Special 4t oil power jet 4t 10w40. Manufacturers recommend using API SJ, SH or SG oils. With gearbox and classic drive. Lubrication system for outboard 4t engines. Motul range for 4t stationary petrol engines.
"Heat engine" - Rocket engine. Gas turbine engine... Ivan Ivanovich Polzunov. Unlike piston engine, in a gas turbine engine processes occur in a flow of moving gas. Traditional poison as a whole is a structure of a nuclear reactor and the actual engine. What is a heat engine? Denis Papin. Solving environmental problems.
There are 31 presentations in total
"Static electricity" - Excess electricity must be removed from the body by grounding. Clothing. Grounding results. For millennia, our ancestors walked the earth barefoot, grounded naturally. Normalization of pressure. "Excess" electricity can lead to serious malfunctions of organs and systems.
"Forces of the body" - The force acts on the connection, and the reaction of the connection on the body. Circle. A surface is considered smooth if friction is negligible. The d'Alembert principle. The theorem on the speed of a point in a complex motion. Force is a sliding vector. Cylindrical hinge. Varignon's theorem. The theorem on the addition of pairs of forces. Rigid termination.
"The history of electricity" - XX century - the emergence and rapid development of electronics, micro / nano / pico-technologies. The history of the development of electricity. 19th century - Faraday introduces the concept of electric and magnetic fields. XXI Century - Electric Energy finally became an integral part of life. XXI century - power outages in household and industrial networks.
"Atomic nuclei" - Diagram of a nuclear power plant. Superheavy nuclei (A> 100). Core sizes. Nuclear forces. Fission of nuclei. The magnetic field is generated by superconducting windings. N? Z diagram of atomic nuclei. Scattering of a β-particle in the Coulomb field of a nucleus. Rutherford's experience. Models of atomic nuclei. Synthesis of nuclei. Nucleus mass and binding energy.
"What physics studies" - Introductory speech of the teacher. Rocket launch. Technique. What does physics study? Eruption. Combustion. Physics. Aristotle is the greatest thinker of antiquity. Thermal phenomena of nature. Magnetic phenomena of nature. Aristotle introduced the concept of "physics" (from the Greek word "fuzis" - nature). Acquaintance of students with a new subject of the school course.
"Igor Vasilievich Kurchatov" - His mother was a teacher, his father was a land surveyor. Beloyarsk NPP is named after Kurchatov. IV Kurchatov - Deputy of the Supreme Soviet of the USSR of the third and fifth convocations. Biography of I.V. Kurchatov, as an outstanding Soviet physicist. In 1960, the Institute of Atomic Energy founded by him was named after Kurchatov. Who is I.V. Kurchatov?
There are 19 presentations in total
Creation of the engine: An old bike circulating that Wankel invented the miracle engine in 1919. It was always hard to believe in her: how could a 17-year-old guy, albeit talented, create such a thing? He opened his own workshop in the city of Heidelberg, and in 1927, drawings of a "machine with rotating pistons" (in German abbreviated as DKM) were born. Felix Wankel received his first DRP patent in 1929 and applied for a DKM engine in 1934. True, he received the patent two years later. Then, in 1936, Wankel settled in Lindau, where he located his laboratory.
Then the authorities noticed the promising designer, and the work on the DKM had to be abandoned. Wankel worked for BMW, Daimler and DVL, the main aircraft engine manufacturers in Nazi Germany. So it is not surprising that before 1946, Wankel had to sit in prison as an accomplice of the regime. The French took out the laboratory in Lindau, and Felix was simply left with nothing. Then the authorities noticed the promising designer, and the work on the DKM had to be abandoned. Wankel worked for BMW, Daimler and DVL, the main aircraft engine manufacturers in Nazi Germany. So it is not surprising that before 1946, Wankel had to sit in prison as an accomplice of the regime. The French took out the laboratory in Lindau, and Felix was simply left with nothing. It was only in 1951 that Wankel got a job at a motorcycle company - the then well-known NSU. While rebuilding the laboratory, he interested Walter Freude, a racing motorcycle designer, with his designs. Together, Wankel and Freude pushed the project forward, and engine development sped up dramatically. On February 1, 1957, the first DKM-54 rotary engine was put into operation. It was fueled by methanol, but by June the engine, which had worked for 100 hours at the stand, was switched to gasoline. It was only in 1951 that Wankel got a job at a motorcycle company - the then well-known NSU. While rebuilding the laboratory, he interested Walter Freude, a racing motorcycle designer, with his designs. Together, Wankel and Freude pushed the project forward, and engine development sped up dramatically. On February 1, 1957, the first DKM-54 rotary engine was put into operation. It was fueled by methanol, but by June the engine, which had worked for 100 hours at the stand, was switched to gasoline.
Work principles rotary engine Wankel engine cycle Wankel engine cycle But then Freude proposed a new concept of a rotary engine! In the Wankel engine (DKM), the rotor rotated around a stationary shaft along with the combustion chamber, which ensured the absence of vibrations. Walter decided to fix the combustion chamber, and let the rotor drive the shaft, that is, use the principle of duality of rotation for a rotary engine. This type of rotary engine was designated KKM. But then Freude proposed a new concept for a rotary engine! In the Wankel engine (DKM), the rotor rotated around a stationary shaft along with the combustion chamber, which ensured the absence of vibrations. Walter decided to fix the combustion chamber, and let the rotor drive the shaft, that is, use the principle of duality of rotation for a rotary engine. This type of rotary engine was designated KKM.
The principle of duality of rotation was patented by Wankel in 1954, but he still used the DKM principle. I must say that Wankel did not like the idea of such an inversion, but he could not do anything - the engine of his favorite DKM type was time consuming maintenance, to change the spark plugs, the motor had to be disassembled. So the KKM engine had much more promise. Its first sample spun on July 7, 1958 (however, it still had candles in the rotor, like on the DKM). Subsequently, the candles were transferred to the engine housing, and it acquired its appearance, which has not fundamentally changed to this day. Now all rotary engines are arranged according to this scheme. They are sometimes called "wankels" after the developer. The principle of duality of rotation was patented by Wankel in 1954, but he still used the DKM principle. I must say that Wankel did not like the idea of such an inversion, but he could not do anything - the engine of his favorite DKM type was time consuming maintenance, to change the spark plugs, the motor had to be disassembled. So the KKM engine had much more promise. Its first sample spun on July 7, 1958 (however, it still had candles in the rotor, like on the DKM). Subsequently, the candles were transferred to the engine housing, and it acquired its appearance, which has not fundamentally changed to this day. Now all rotary engines are arranged according to this scheme. They are sometimes called "wankels" after the developer.
In such an engine, the rotor itself plays the role of the piston. The cylinder is a stator in the form of an epitrochoid, and when the rotor seals move over the surface of the stator, chambers are formed in which the combustion process takes place. In one revolution of the rotor, this process occurs three times, and thanks to the combination of the shapes of the rotor and stator, the number of strokes is the same as that of a conventional ICE: intake, compression, working stroke and exhaust. In such an engine, the rotor itself plays the role of the piston. The cylinder is a stator in the form of an epitrochoid, and when the rotor seals move over the surface of the stator, chambers are formed in which the combustion process takes place. In one revolution of the rotor, this process occurs three times, and thanks to the combination of the shapes of the rotor and stator, the number of strokes is the same as that of a conventional ICE: intake, compression, working stroke and exhaust.
The rotary engine does not have a gas distribution system - the rotor works for the gas distribution mechanism. He himself opens and closes the windows at the right time. He also does not need balance shafts, a two-section engine can be compared with a multi-cylinder internal combustion engine in terms of vibration level. So the idea of a rotary engine in the late fifties seemed like a stepping stone for the automotive industry into a brighter future. The rotary engine does not have a gas distribution system - the rotor works for the gas distribution mechanism. He himself opens and closes the windows at the right time. He also does not need balance shafts, a two-section engine can be compared with a multi-cylinder internal combustion engine in terms of vibration level. So the idea of a rotary engine in the late fifties seemed like a stepping stone for the automotive industry into a brighter future. Into the series! Into the series!
The first engine: The engine was developed in conjunction with NSU and in 1957 gained momentum for the first time. One of the 4 built experimental engines stands today in the Deutsches Museum in Munich. Indicators: 250 cm3 and 29 hp. at min-1, and in 1963 NSU began production of the Spider model - the first production car with rotary piston engine... The motor was developed in conjunction with NSU and in 1957 gained momentum for the first time. One of the 4 built experimental engines stands today in the Deutsches Museum in Munich. Indicators: 250 cm3 and 29 hp. at min-1, and in 1963 NSU began production of the Spider model - the first production car with a rotary piston engine.
Advantages and disadvantages of the engine: The design allows for a four-stroke cycle without the use of a special valve timing mechanism. This engine can use cheap fuels; it creates almost no vibrations. The design allows for a four-stroke cycle without the use of a special gas distribution mechanism. This engine can use cheap fuels; it creates almost no vibrations. The main advantage of the Wankel engine is its small size for a given power. The engine has few moving parts and is therefore potentially more reliable and cheaper to manufacture. The main advantage of a Wankel engine is its small size for a given power. The engine has few moving parts and is therefore potentially more reliable and cheaper to manufacture
