上市公司需要付出什么论目前中国证券市场的功能缺陷

1、汽车构造重点（key automotive construction）automobile structure are summarizedthe same point 1, four stroke diesel engine and gasoline engine and different points.answer: the same point: each cycle through the intake, compression, power and exhaust stroke four.different points: (1) the combustible mixture f

2、ormation in different ways: gasoline engine in cylinder air-fuel mixture,the diesel engine is inhaling pure air, combustible mixed gas of diesel engine is formed close to the end of the compression ignition (2);in different ways: gasoline engine is at the end of the compression ignited by an electri

3、c spark, the diesel engine is a compression ignition; (3) compression ratiodifferent; (4) the different fuel supply system.2, why should be reserved for the valve clearance? why is too large or too small are not good?answer: because when the engine works, the valve will be expanded as the temperatur

4、e rises, cause the valve is not tightly closed byleak engine compression and power stroke, so that the power down, dont even start easily when serious.the clearance between the transmission parts and valve and valve seat collision sound, accelerated wear, but also makethe duration of valve opening i

5、s reduced, the deterioration of inflation and exhaust conditions of the cylinder. the gap is too small will occur in the hot stateleakage, power down, and even burned valves.3, diesel engine, gasoline engine in combustible mixture formation differs from the ignition mode? why not the compression rat

6、iothe same?answer: gasoline engine in cylinder air-fuel mixture, diesel engine intake. pure air, combustible mixed diesel enginethe gas formed close to the end of the compression. at the end of the gasoline engine is compressed by electric spark ignited, diesel engine is a compressionspontaneous com

7、bustion. therefore, diesel fuel injected into the cylinder, in a very short period of time is mixed with air immediately by burning itit is because the two different ways of ignition, resulting in diesel engine needs a higher compression ratio.what is the role of the 4 engine, forced circulation wat

8、er cooling, and the circulating water.answer: role: to improve the coolant pressure by pump, forced circulating cooling fluid in the engine.circulating water: water pump, water pipes and water bodyup / downthrough the radiator thermostat through the cylinder head jacket5, the engine temperature is t

9、oo high or too low, what harm?answer: (1): high temperature metamorphic lubricating oil, the oil film parts cant keep normal; (2) heating partsthe expansion is too large and the destruction of normal clearance; (3) to the mechanical properties of metal materials decreased, so that can not affordthe

10、normal load.low: (1) fuel evaporation, combustion quality deterioration; (2) the oil viscosity increases, the friction loss and; (3) increase the corrosion wear of the cylinder.these adverse consequences will lead to reduction of engine power, economic deterioration, loss of life.7, the composition

11、of overhead type gas distribution mechanism, how it works?composition: the valve group comprises a valve, valve guide, valve main spring, valve spring retainer, valvethe transmission group comprises a rocker shaft and rocker arm, push rod, camshaft, tappet, timing gear.when working, the crankshaft d

12、rives the camshaft rotating through the timing gears, cam projections from the top of the tappet, throughthe push rod rocker swing, compress the valve spring, the valve from the seat (or valve opening), cam projections fromafter opening, the valve closed by spring force.8, the ignition advance angle

13、 on engine performance impact, how to realize its adjustment.when the valve opening, speed increased, w increased, ignition angle, or continue to work forprocess, the dynamics of economic decline. a certain speed, load increases, solar term door opening increases, the concentration of the mixed gas.

14、high combustion speed increases, advance angle decreases.adjusting device: centrifugal advance adjusting device, it can automatically adjust according to changes in engine speed; reallyair ignition control device, it can automatically adjust with the change of load.how to penetrate the generated vol

15、tage ignition system of gasoline engine, 9?by connecting breaker periodically and cut off the ignition coil primary circuit, a current changes,in order to generate high voltage in the two winding of the ignition coil, and then by the distributor according to the working time of cylindersin order to

16、distribute the spark plug of each cylinder.what are the main drive system of 11. car assembly? and then tell their role.answer: automotive transmission system is composed of a clutch, gearbox, universal transmission device and drive axle.the basic function of the clutch:(1) in the car started, by gr

17、inding slip between the clutch driving and driven parts and make them by speedgradually close, to ensure a smooth start the car;(2) in the transmission, transmission through the rapid separation of clutch parts to cut off the power of the master,in order to reduce the impact between gear teeth, ensu

18、re shift smooth;(3) when the maximum torque to the clutch is greater than the energy transfer, the main part, fromwill produce friction, to prevent transmission overload;the basic function of transmission:(1) to change the transmission ratio, enlarge the driving wheel torque and speed range, in orde

19、r to adapt to constantly changing drivingthe conditions, such as starting, acceleration, climbing and so on, and make the engine work in favorable conditions;(2) unchanged in the direction of rotation of the engine, the car can be driven back;(3) the use of neutral, interruption of power transmissio

20、n, so that the engine can start, idle, and convenient for transmissionstop or power output.the main function of the universal transmission device:to achieve a dynamic between shaft axis intersection and relative position of constantly changing transmission.the basic function of the drive axle:(1) th

21、e universal transmission device from the engine speed through the main reducer, differential and axle tothe driving wheels, reduce speed and increase torque;(2) the direction of transmission for cone gears to change the torque through the main reducer;(3) through the implementation of differential w

22、heels on both sides of a differential effect, ensure the inner and outer wheels turn at different speeds.the 12. basic components of the automobile clutch, and explain how it works.answer: the friction clutch is mainly composed of a driving part, the driven part of the pressing mechanism and a contr

23、ol mechanism is composed of four parts.work process: engine torque on flywheel (active component) and the driven disc friction between surfaces andtransferred to the driven plate, in which a series of parts of the transmission shaft and the first drive system to driveround. the pressing force of the

24、 spring is larger, torque clutch can transfer the greater.the 13. shift gear transmission(see p43-p44)14. ordinary cross shaft rigid joint to achieve the purpose of equiangular speed transmission must meet the requirements of what?answer: (1) the first two equal angles of universal joint angle betwe

25、en the joint between the two and second;(2) the first universal joint fork driven plane and the second gimbal 2 active fork 3 plane in the same planethe basic structure and working principle of 15. differential?answer: symmetrical bevel gear differential by planetary gear, planetary gear shaft, axle

26、 shaft gear and the differential case etc.working principle: the power of the main reducer driven bevel gear in the differential case, cross shaft, planetary gear and axlethe gear and axle output to the drive wheels. when both sides of the wheel at the same speed of rotation is around half shaft, pl

27、anetary gearline rotation - revolution; if the resistance is different on both sides of the wheel, planetary gear in the revolution at the same time, alsorotating around its own axis of rotation. therefore, half shaft gear drives the wheels to rotate at different speeds.16. what is the role of the f

28、rame, what are the requirements of the frame?answer: the frame is the function of each component bearing connected cars, and under various loads from inside and outside.the frame structure should first meet the requirements of automobile layout;it should have enough strength and properstiffness. in

29、order to improve the level of lightweight vehicle requirements, the quality of the frame is as small as possible. in addition, the frame should be clothis closer to the ground, so that the gravity position is reduced, is conducive to improving the vehicle stability. thisone of the cars and buses is

30、particularly important.17. bidirectional shock absorber is how to work?answer: the role of two-way shock absorber can be divided into two compression and expansion stroke illustrated.(1) the compression stroke: when the car wheel rolling on the convex and concave rolled, the wheel moved near the fra

31、me (body),the shock absorber is compressed, the shock absorber piston downwards. the chamber below the piston (ivc) to reduce the volume of oil.pressure oil flow into the chamber above the piston through the flow valve (cavity). the superior is a piston rodoccupies a part of space, the volume of cav

32、ity increased less than the volume of the cavity decreases, there is a part ofthe oil pushing compression valve, back into the oil cylinder. the throttle valve on the oil is formed on the suspension compressionthe damping force of the movement.(2): promote travel when the wheels rolled into pits or

33、rolled off the bulge, the wheel body relatively away by shock absorberstretch. the shock absorber piston moves upward. the piston chamber pressure increases, the circulation valve is closed. the chamberthe fluid will open the valve into the inferior vena cava dilatation. also, due to the piston rod,

34、 since the cavity flowthe oil is not enough to increase the volume with inferior vena cava, inferior vena generated within a certain vacuum, thenthe oil storage cylinder in the compensation valve will open into the inferior vena cava to supplement. at this time, the throttle valvethat is the formati

35、on of damping force of suspension extension movement. steering wheel18. with the composition of the steering system diagram19. hydraulic brake mainly by which parts, how is its basic work?answer: hydraulic brake mainly by the brake pedal mechanism; brake master cylinder; tubing; before and after the

36、 brake and brakewheel cylinder.the brake pedal, the brake master cylinder brake fluid through the tubing is pressed into the front and rear brake wheel cylinder, brake shoepush the brake drum. before the brake clearance disappears, the hydraulic lines can not be very high, as to balance systemmovabl

37、e shoe return spring tension and oil in the pipeline flow resistance. the brake clearance disappeared and start productionsystem dynamic torque, fluid pressure and pedal force began to grow, until completely braking. from the beginning to the brake system completelyin the process of moving, due to t

38、he presence of hydraulic tubing (mainly rubber hose) the elastic deformation and frictionclean the components of the elastic compression deformation, pedal and wheel cylinder piston can move a distance. release the brake pedalplate, brake and wheel cylinder piston return spring in return, will be ba

39、ck to the main brake hydraulic cylinder.glossary:1 the maximum loading quality: the maximum quality of cars on the road when the capacity ofthe 2 axle load distribution: the mass distribution of car to the front, the rear axle ratio, expressed as a percentage3: by turning radius steering center to s

40、teering wheel and the ground contact point distance, called the turning radius of the car.4 bdc and tdc: insertion of the top surface of the piston farthest from the crankshaft centre line, known as tdc piston;from the top surface of the crankshaft centerline recently at the stopping point, called t

41、he next stop point.5 stroke piston: piston movement of the upper and lower two check the distance between points is called the piston stroke.6 cylinder volume: volume of the piston movement of a cylinder in a stroke of the swept volume called cylinderproduct.7 compression ratio: the compressed gas c

42、ylinder before the maximum volume and minimum volume after compression ratio, namely the total cylinderthe volume and the volume ratio of combustion chamber.8: because of deflagration gas pressure and high temperature in the combustion chamber is ignited combustible end far from the centermixed gas

43、spontaneous combustion caused by an abnormal combustion.9 piston pin offset: piston pin hole center line deviation from the center line of plane piston10: a total engine displacement engine all the working volume of the cylinder is called the engine displacement.11 engine load: refers to the engine

44、driving power consumption driven machine or effective torque, can also beas in a load of the engine speed, engine power is then issued with the same speedmay a maximum power ratio, expressed as a percentage.12: the internal combustion engine is the rate of pressure rise rate of pressure rise (dp/d.)

45、13 full support: crankshaft between two adjacent curved turn crankshaft are set to a main journal, called the whole teamcrankshaft support.phase 14: with gas with the crank angle, exhaust valve opening and duration.15 the concentration of combustible mixture: excess air coefficient is equal to 1 for

46、 the theory of mixed gas is greater than 1 for the lean mixturegas, less than 1 for the rich mixture.16: 1kg fuel combustion excess air coefficient of the actual supply of air quality / complete combustion of fuel required for 1kgthe theory of air quality17 charge (amount): the actual volume coeffic

47、ient of each working cycle engine (fresh mixture into the cylindergas or air) ratio and intake under the condition of full theoretical impulse the cylinder volume.18 valve cone angle: valve sealing surface is called valve cone angle, cone angle.19 valve overlap angle (overlap): the intake end point

48、before the opening at the top, and the exhaust valve before tdcclose, there is a period of time in the intake and exhaust valve open at the same time phenomenon. this phenomenon is called gasgate overlap, crank angle overlap period is called valve overlap angle.20 valve clearance: in the cold engine

49、 assembly, the valve and the transmission has certain gap,with the expansion of the heated compensation valve. this gap is called the valve clearance.21 contact gap: separate the contacts of the breaker, the largest gap between contacts into contact gap.22: the gap breakdown voltage through the volt

50、age between the two electrodes of the spark plug and spark needed, saidthe breakdown voltage for spark plug.23 idle: refers to the engine running at the lowest speed in the case of no external power output. the mixed gas combustionthe burn after work, just to overcome the internal resistance of the

51、engine, allowing the engine to maintain minimum speed and stable operationturn.24 fuel injection advance angle: refers to the top surface of the plunger piston from the closed oil hole to the upper stop point of the piston, crankshaft rotationthe angle.25 cooling water circulation: when the coolant

52、temperature reaches the specified value, and gradually began to melt into liquid paraffin,volume increases and compression hose to shrink. in the contraction of the hose at the same time, the action of the push rod in an upward pushpower。 the push rod is fixed on the upper end of the push rod, there

53、fore, hose and temperature produced the downward reverse thrust of the valve openingrev. when the coolant thermostat valve into the radiator, and the radiator through the water pump to the engine by and largecycle.easy to remember, with water pipes and pump, radiator, radiator, water outlet pipe (ta

54、nk)26 small circulating cooling water: when the temperature drops below the set value, the thermostat temperature in a solid paraffin,the thermostat valve closes the coolant flow to the radiator channel under the action of the spring, the cooling fluid through the bypass hole, water pumpreturn engin

55、e, small circulation.easy to remember: water, water, water jacket, water pump, the water outlet pipe (thermostat)27 pressure lubrication: pressure lubrication is a certain pressure to get into the lubricating oil for lubrication friction surface.28 clutch pedal free stroke: when the clutch is in a n

56、ormal state of engagement, the separation sleeve is pulled back springto the limit position, leave the gap should be between separation and separation of bearing inner end of the lever, to ensure frictioncan still fully engaged in the normal wear process of clutch. because of the gap, the driver in

57、the pedalthe clutch pedal, to eliminate the gap, and then we can start clutch. in order to eliminate the gapthe clutch pedal travel required, called free travel for the clutch pedal.the 29 main reduction ratio: refers to the automotive drive axle of the main gear transmission ratio is equal to the rotation angle of the drive shaftfaster than the angular velocity of car axle, is equal to their speed ratio.30: direct drive power directly from the first shaft to the second axis, rather