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1、 附 录附录 A:英文文献AUTO ELECTRIC APPLIANCES1、Starting SystemAutomobile engines are not self-starts. In order to start them, the engine crankshaftmust be turned over. To do this, the starter motor receives electrical power form the storagebattery. The starter motor then converts this energy into mechanical
2、 energy, which ittransmits through the drive mechanism to the engines fly wheel.The starter motor draws a great deal of electrical current from the battery. A largestarter motor might require 300 to 400 amperes of current. This current flows through theheavy gauge cables that connect the battery to
3、the starter.The drive controls the flow of this current using the starting switch. However, if thecables were routed from the battery to the starting switch and then on to the starter motor,the voltage drop caused b resistance in the cables would be too great. To avoid this problem,the system is des
4、igned with two connected circuits: the starter circuit and the control circuit.1.1 The starting safety switchThe starting safety switch is also called a neutral start switch. It is a normally openswitch that prevents the starting system from opening when the automobiles transmission isin gear. If th
5、e car has no starting safety switch, it is possible to spin the engine with thetransmission in gear. This will make the car lurch forward or backward which could bedangerous. Safety switches or interlock devices are used with all automatic transmissionsand on many late-model cars with manual transmi
6、ssions. The safety switch can be anelectrical switch that opens the control circuit if the car is in gear. It can also be amechanical interlock device that will not let the ignition switch turn to start if the car is inthe gear.1.2 Magnetic Switch (Relays and Solenoids)A magnetic switch in the start
7、ing system allows the control circuit to open and closethe starter circuit. The switch can be a:()Relay which uses the electromagnetic field of a coil to attract an armature and close the contact points.()Solenoid which uses the electromagnetic field of a coil to pull a plunger into thecoil and clos
8、e the contact points. The plungers movement can also be used to do amechanical job, such as shifting the starter motor gear in a solenoid-actuated drive.1.3 Starter MotorThe starter motor converts electrical energy from the battery into mechanical energy toturn the engine. It does this through the i
9、nteraction of magnetic fields. When current flowsthrough a conductor, a magnetic field is formed around the conductor. If the conductor isplaced in another magnetic field, the two fields will be weakened at one side andstrengthened at the other side. An automotive starter motor has many conductors a
10、nd uses alot of current to create enough rotational force to crank the engine.The armature is the collection of conductors that will spin to crank the engine. Thestarter drive gear is mounted on the armature shaft. The pole pieces are the stationarymagnetic fields. The motor housing encloses the arm
11、ature and pole pieces, holds thebearings that support the armature shaft, and provides the terminals for connecting themotor to the rest of the staring system.2.I gniting SystemThe ignition system on an internal combustion engine provides the spark that ignitesthe combustible air/fuel mixture in the
12、 combustion chamber. The spark consists of anelectric are produced by applying a high voltage across the electrodes of a spark plug. Thisspark must occur near the end of the compression stroke, as the position approaches topdead center (TDC). The cylinders must fire in the proper order and at a prec
13、ise instant,depending on engine speed, load and temperature conditions.A spark plug consists of a pair of electrodes called the center and ground electrodes,separated by a gap. A spark is produced by applying a high voltage (from approximately 6KV to 40 KV) between the center electrode and ground. O
14、nce the arc is started, a muchlower voltage is required to sustain the arc to ignite the air/fuel mixture.The ignition system is divided into two circuits: the primary and the secondary. Theprimary circuit is the low-voltage side of the system and controls the secondary circuit,which is the high-vol
15、tage side of the system.The following are the basic parts of the primary ignition circuit:()Battery and/or alternator. Supplies the low voltage (12V) used to operate theprimary circuit.()Ignition switch. Key-operated switch used to feed battery voltage to the primarycircuit. () Primary wires. Low vo
16、ltage wires used to connect the electrical components ofthe primary circuit.() Ignition coil primary winding. Current flow through the coil produces anelectromagnetic field, which is used to induce a high voltage in the secondary coil.() Electronic control unit. Contains a switching transistor contr
17、olled by a speedsensor and is used to open and close the primary circuit.()Speed sensor, or pickup. Produces a pulsating voltage that signals the generationof an ignition spark.The following are the basic parts of a secondary ignition circuit:()Ignition coil secondary winding. Has a high voltage (40
18、,000 V or more) inducedin it each time the primary magnetic field collapses.()Coil wire. Heavily insulated wire that feeds high voltage from the ignition coil todistributor cap.() Distributor rotor. Operates in conjunction with the distributor cap to distributethe high voltage from the ignition coil
19、 to the individual spark plug wires in the firing order.() Distributor cap. Insulated cap that transfers high voltage from the distributorrotor to spark plug wires.() Spark plug wire. Heavily insulated wire that carries high voltage from thedistributor to the spark plugs.()Spark plug. Provides the a
20、ir gap within the combustion chamber for the highvoltage to arc across, thus igniting the air/fuel mixture.、Lighting CircuitThe lighting system in a typical automobile includes the headlight, parking lights,direction-signal lights, side marker, stoplights, tail lights, and interior lights.3.1 Main L
21、ighting SwitchThe main lighting switch (sometimes called the headlight switch) is the heart of thelighting systems. It controls the headlights, parking lights, side marker lights, taillights,license plate light, instrument panel lights, and interior lights.Individual switches are provided for specia
22、l purpose lights such as directional signals,hazard warning flashers, back up lights, and courtesy lights. The main lighting switch maybe of either the “push -pull” or “push -pull with rotary contact” types. A typical switch willhave three positions: off, parking, and headlamps. Some switches also c
23、ontain a rheostat tocontrol the brightness of the instrument panel lights. The rheostat is operated by rotating thecontrol knob, separating it from the push-pull action of the main lighting switch. When the main lighting switch completes the circuit to the headlamps, the low beamlights the way for c
24、ity driving and for use when meeting oncoming traffic on the highway.When the dimmer switch is actuated, the single filament headlamps go “on”, along with t hehigh beam of the two filament headlamps. The next actuation of the dimmer switch returnsthe headlight system to low beams only on the two fil
25、ament lamps. Some cars are equippedwith and electronic headlight dimming device, which automatically switches the headlightsfrom high beam to low in response to light from an approaching vehicle or light from thetaillight of a vehicle being overtaken. The dimmer switch in the automatic headlampdimmi
26、ng system is a special override type. It is located in the steering column as part of acombination dimmer, horn, and turn signal switch. The override action occurs when a slightpull toward the driver on the switch lever providers high beam headlights regardless of theamount of light on the sensor-am
27、plifier.For some years there has been discussion about the advantages of a polarized headlightsystem. Such a system comprises headlights which produce polarized light in a particularplane. The windscreens of all cars would be fitted with polarizing glass, which would beoriented so that glare from an
28、 approaching vehicle would be essentially eliminated, whilethe forward vision would still be kept at the present levels. The advantages the systemappear attractive, but the practical problems of making the transition are very great, since itwould not be practical to convert all existing vehicles to
29、this type of lighting. Also, anybenefits would only be marginal because glare itself is not a frequent cause of accidents.However, many cars now have refracting or colored glass to cut down on glare.3.2 Directional Signal SwitchThe directional signal switch is installed just below the hub of the ste
30、ering wheel. Amanually controlled lever projecting from the switch permits the driver to signal thedirection in which he wants to turn. Moving the switch handle down will light the “turnsignal” lamps on the left front and left rear of the car, signaling a left turn. Moving theswitch upward will ligh
31、t the turn signal lamps on the right (front and rear), signaling a rightturn. With the switch in a position to signal a turn, lights are alternately turned “on” and“off” by a turn signal flasher. Incorporated in the directional signal switch is a “lane changeswitch mechanism”. This feature provides
32、the driver the opportunity to sign al a lane changeby holding the turn lever against a dent, then releasing it so cancel the signal immediatelyafter the maneuver is completed.3.3 Stoplight SwitchIn order to signal a stop, a brake pedal operated “stoplight switch” is provided tooperate the vehicles s
33、top lamps. In addition to lighting the conventional rear lights, the switch also operates the center high-mounted stop lamp, which became mandatory on latermodels. Cruise control equipped vehicles may also utilize a vacuum release valve. In thiscase, both the vacuum release valve and the stoplight s
34、witch are actuated by movement ofthe brake pedal. 附录 B:中文文献1、启动系统汽车电器汽车发动机是不能自动启动的。为了启动发动机,曲轴必须先运转起来。为此,启动机必须从蓄电池得到足够的电能。接着启动机将这部分电能转化成机械能,通过驱动机构传到发动机曲轴飞轮上。启动机需要蓄电池提供大量的电流。一个大型的启动机需要大约 300400 安培的电流。电流通过重型电缆从蓄电池连接到启动机上。驾驶员通过启动开关来控制这个电流。如果导线从蓄电池经过启动开关连接到启动机上,在导线上会产生大量的电压降。为了避免这个问题,启动系统设计有两套电路:启动机电路和控制电路。1.1 安全启动开关启动安全开关又称为空
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