工程机械底盘设计备用考试题

1、工程机械底盘设计备用考试题（Standby test for construction machinery chassis design）The tracked vehicle steering control mechanism 2. is composed by steering clutch and brake, steering, driving force is less than the slow track driving force fast track.3. planetary gearbox gear selection, in addition to meet the r

2、equirements of the transmission ratio must be installed to meet certain conditions, namely concentric assembly condition of adjacent conditions.4. friction, friction plate diameter and torque reserve coefficient is the main parameter of main clutch design.5. semi floating axle by means of a direct b

3、earing support structure at the outer end of the axle half shaft; full floating axle shaft is the axle housing with two side far away from the bearing support structure in the wheel hub.6. torque converter pump wheel speed, caused by the change of the load performance of the pump wheel torque change

4、 called torque converter through wear.At present, 12. middle gear transmission ratio to determine the main speed continuously and make full use of the two principles determined by the rate of the engine; the first method, should make the transmission gear ratio of a geometric progression.The input c

5、haracteristics of 13. hydraulic torque converter is the torque converter pump wheel speed and pump wheel torque, it is composed of many parabolic curves.14. steering wheel, front axle and steering knuckle between three and frame must be relatively certain that, according to a certain relative positi

6、on of the installation of the steering wheel is called steering wheel positioning.15. drive axle is the function of the engine power will come from the gearbox by slow down and increase torque and change the rotation direction, assigned to the left and right driving wheels and allow it to rotate at

7、different speed.16. wheel drive axle drive bevel gear support structure with cantilever, cross arm type in two ways.17. torque converter can automatically according to the change of load automatically adjust the output torque and rotational speed, improves the adaptability of automatic machine.18. t

8、he characteristics of diesel speed curve machine and input characteristic curve drawing of the converter together, get the input characteristic of hydraulic torque converter working together with the diesel engine, it reflects the relationship between the working point of diesel engine and the torqu

9、e converter transmission ratio.19. when the torque converter turbine inlet radius is larger than the exit radius, turbine flow is the flow of the torque converter axis of the torque converter of this type is called centripetal turbine torque converter.The 20. shift operation of power shift gearbox i

10、s through the hydraulic system with the power of the engine to achieve, it can be divided into fixed axial and centrifugal two types.21, determine the load calculation of transmission system in two areas to consider the maximum output torque and adhesion of diesel engine or torque converter at.22, a

11、 single joint planetary row in the two elements, the planetary transmission ratio is 1.23 wheel mechanical steering system steering system with front wheel deflection, the deflection of rear wheel, all wheel steering type, oblique steering, articulated steering, steering slip24 evaluation indexes, t

12、he braking performance is to measure the braking distance.The necessary and sufficient conditions for 25. vehicles on the ground level is P =Pk=Pkp+Pf.26, the braking performance is usually measured by the braking distance, it refers to the manipulation process of mechanical brake mechanism to start

13、 stop completely in machinery28, for the constant velocity cardan joint, when the two are connected to the driving shaft of the angular velocity is constant, the angular velocity of the driven shaft change in COS * COS and Alpha Omega Alpha / Omega, active. One week, 1 weeks driven.29, power shift g

14、earbox, clutch gear number in the number of degrees of freedom under the same conditions, the smaller gear clutch less idle clutch shift control system more simple.30, the gearbox into human shift gearbox and power shift gearbox two categories. Human shift gearbox shift into mobile gear shift gear s

15、ets by shifting and synchronous shift three.31, in order to obtain the maximum traction power input characteristic curve to work together on the transmission torque converter at maximum efficiency than the corresponding parabolic load through the diesel engine rated working point, so that the machin

16、e can obtain the maximum powerThe best braking state 32, we usually refer to the wheel of the locking but not locking.34, mechanical traction efficiency is equal to the transmission efficiency, slip efficiency, rolling efficiency of the product.35, to the four connecting rod mechanism for front whee

17、l steering, which can be divided into the steering front rear steering trapezium, trapezoid, usually give priority to the rear (Ackerman steering mechanism will be arranged in the front axle after)36, the main high-grade than low-grade started starting clutch friction work big.37, the characteristic

18、 parameters of the planetary gear is the sun gear and the number of the ratio of the number of.38, cardan joint with the increase of the angle between the driving shaft of the driven shaft, the additional bending moment increases, the transmission efficiency.2. explain the shift action planetary pow

19、er shift gearbox is how to achieve, and explain the planetary transmission locking phenomenon and its effect.To achieve: planetary power shift gearbox has many planetary gear shifting action, mainly by brake planetary rows to achieve, only by few planetary gear clutch locking in planetary transmissi

20、on if a planetary sun gear and planet carrier gear, three components of any two equal speed third, the speed is inevitable with the first two equal. Often use this method to achieve direct block3. of the torque converter and the concept, structure and characteristics and analysis of single phase tor

21、que converter. Phase - torque converter working state number. Between the pump wheel and the guide wheel or between the guide roller and the guide wheel is rigidly connected number called turbine stage of torque converter.The concept of the 4. clutch torque reserve coefficient and determination meth

22、od.Why are the main clutch torque reserve coefficient: in order to ensure the main clutch can reliably transfer the engine and has a certain ability of life, must make the main clutch friction torque transfer with a certain amount of reserve. Considering the factors (1), the maximum torque of fricti

23、on wear after still can reliably transfer the engine; (2) to prevent slipping clutch itself is too large; (3) to prevent transmission overload.11. wheel braking force should be allocated?When the mechanical structure, the position of the center of gravity when the ratio of the front and rear wheel b

24、raking force is a function of friction coefficient of the road. Low speed, generally only on the driving wheel brake set. Medium speed machine, the first locking rear. High speed machinery, and front and rear wheel lock.How to point 12. articulated frame design?The general arrangement, should first

25、consider hinge point layout should first meet the working performance of the machine in the middle of the front and rear axle pivot point arrangement. Layout of hinge point, also want to consider the convenience and possibility of maintenance structure.How to choose the 13. wheeled mechanical steeri

26、ng?Deflection wheel steering: integral frame steering is realized by the relative deflection wheel frame. Articulated steering articulated frame, the steering is through the front and rear frame to achieve relative deflection, slip integral steering frame, the steering is by changing the left and ri

27、ght sides of the wheel speed to achieve.14. what is the two factors that influence the braking force?The driving force from the ground adhesionTotal drive 15. transmission ratio is how to allocate?Because the engine is generally high speed machine parts, so in order to reduce the torque transmission

28、 of the bearing parts, according to the power transmission direction, the transmission ratio is behind the parts should be as large as possible. That is to say, take if as large as possible, then take I0 as large as possible, and finally determine the IK according to the needs of the sigma I.The arr

29、angement of 16. fixed power shift clutch shaft in the gearbox position should consider what the problem?Clutch can be installed in the driving gear shaft, can also be installed in the passive gear shaft. In the gearbox transmission ratio is determined, due to the different clutch position, work torq

30、ue closing, idling speed separation is also different.The 17. main clutch reserve coefficient value is too large or too small for the main clutch has what effect?If we take larger values, increase working reliability, combined with the process of time,Dynamic load time is shortened, slipping time sh

31、ortened, and long service life;(2), if the value is not too large, to prevent transmission of the overload, but also make the clutch structure parameter increases, the pressing force is increased, the body weight increased;(3) if the smaller, lower reliability, combined with the process of time, loa

32、d time, friction time increases, the reduction of the service life.The design steps of 19. human shift transmission1. according to the number of stalls and stall transmission ratio, transmission scheme drafting gear box.2. to determine the main parameters of the gearbox, including center distance an

33、d gear modulus, tooth width, and angle of helical gear etc.3. according to the transmission gear ratio selection, determine the gear tooth number4. gear shaft bearings and other parts of the life calculation or stiffness, strength calculation.5. structural design, assembly drawing and parts.The char

34、acteristics of the 20. planetary gear box power cycleThe cycle performance not only in the internal, external. The main power and the same students out. The existence and size depends only on the planetary structure, and the transmission ratio is independent of the size ofThe characteristics and app

35、lications of the 21. type of human space shift transmission.The input shaft, intermediate shaft and output shaft is the spatial arrangement of the triangle. Good structural rigidity; can easily obtain a plurality of reverse control mechanism is more complex than the efficiency of plane three gear bo

36、x; box structure than three plane gear box complex. For backward frequent machinery, such as a bulldozer.Characteristic and application situation of the 22. plane shaft type three human shift transmission.The input shaft and the intermediate shaft and the output shaft in the same planeThe output sha

37、ft is supported on the internal gear input shaft, poor rigidity, poor internal bearing working condition is difficult to obtain a plurality of reverse. For backward mechanical equipment not too frequent, and the transmission hydraulic driving system.24. treatment method of fixed shaft power shift ge

38、arbox gear high speed range at.1) when the transmission range is very large, we can use the multi degree of freedom two gearbox series into multi DOF transmission solution. Usually the earthmoving machines in the same gear, reverse gear faster than fast forward, then reversing mechanism should be in

39、 the front.2) if the speed range of reversing mechanism is relatively large, can be designed as a series system of two degrees of freedom of the gearbox.3) in the convenience of operation has little effect under the condition of using mixed shift scheme. The clutch engagement sleeve and mixed shift

40、way. The engaging sleeve can transfer larger torque, idle speed can also have relatively high26. wheel drive axle design requirementsReasonable allocation of transmission components than each component should have sufficient life, light weight, small volume. The supporting structure of shaft well. Y

41、i Weixiu, has the advantages of simple structure, easy manufacture, stable work. When the two driving wheel adhesion coefficient ranges, to better play the driving force.That caterpillar conventional drive axle and characteristics of high drive type drive axle.40. conventional drive axle has the adv

42、antages of simple structure, reliable performance, low cost. Disadvantages: steering side track capacity can not fully play; trajectory steering is often broken, it is difficult to control and difficulty, inconvenient maintenance.Advantages: high drive type drive axle drive sprocket from walking fra

43、me, improve the working conditions of machine transmission system. The wet multi disc brake, the brake to reduce power consumption. Drive component module assembly, easy disassembly and maintenance. Disadvantages: complex structure, difficult manufacture, high cost, increase the focus.The 28. Wheele

44、d Construction machinery running through the main geometric parameters of what?Minimum ground clearance of H close to the angle and the angle of departure by radius 1 beta longitudinal transverse radius by 2 maximum wading depth H130. articulated frame joint arrangementThe drive shaft and the frame

45、hinge point to point in a plumb line.The output shaft and the input shaft, intermediate shaft should be in the longitudinal plane within the machine.Hinge point O should be arranged in the two hinge point of the joint A and B intermediate. In order to achieve constant velocity transmission30. design of constant velocity cardan joint, the driven shaft angle should be how to design good? WhyWhen the driving shaft and the driven shaft in the same plane, the constant velocity conditions for transmission:(1) A2 2 and the intermediate shaft angle equal to the angle between A1 and a driven s