机电数控英语课后习题答案doc文档格式.docx

1、5.the basic wheel主动齿轮 10.材料强度IIIFill in the blanks with the proper word form if necessary.1.gears 2.standardize 3.reliability 4.Machinery 5.assemble ponents 7.uniformity8.estimate 9.expectancy lO.individualIV.Translate following sentences into English.1 最 The most common machine element is the gear,

2、 which combines the feature of the wheel and the lever to form a toothed wheel.2.The hardness of a gear determines its ability to resist wear,3.Manufacturing engineers have centered their efforts on the development of standardized elements4 These parts are produced in large quantities with a high de

3、gree of perfection at reduced cost.5.It seems that the machine part surface is the carrier of functional information for both machine element and processing apparatus,6.Proper application of these machine elements depends upon knowledge of the force on the structure and the strength of the materials

4、 employedI Exercises 第 2 章1.Do you know why there are so many types of bearings?There are many types of bearings because of variations in the design of rings and separators and in the number of balls.2.For what reason are deep groove radial ball bearings mas widely used?Although deep groove ball bea

5、rings are designed to carry a radial load, they perform well under a combined radial and thrust load ,For this reason jt is the most widely used type of ball bearing.3.According to the text,how many types can be divided into?what are they?The bearings can be divided into 6 types,that is ,deep groove

6、 ball bearings ,filled -notch ball bearingsangular contact bearingsself-aligning ball bearingsthrust ball bearings and roller bearings.4.Why can roller bearings higher load than the same size ball bearings?Because it has line contact instead of point contact.5.Depending onits size,after increasing b

7、earingJs it true?Yes,it is true.1. 轴承承载能力一bearing load capacity 6.深沟球轴承2. 径向载荷 radial load 7.角接触球轴承3. 滚柱轴承 roller bearing 8调心球轴承4. 轴向载荷 thrust load 9推力球轴承5.公共球面滚道一common spherical race 10填充式滚球轴承III1.According to their.and a （combination）of thrust and radial loads.2.The races are diameter in（deep gro

8、ove ballbearings3.To increase the bearing（load capacity）4.Unidirectional thrust to（support）combined loads.5（seld-aligning ball）6Wound-rotor motor requires additional secondary controLSynchronous may be used for almost any constant-speed drive requiring about 100 hp or over.S.Synchronous motor requir

9、es a source of de excitation and special synchronizing control.Exercises 第 7 章IX.What is the definition of the transducer?A transducer is a device which converts the quantity being measured into an optical,mechanical or more commonly electrical signal.2.Capacitance inductance transducersmagnetoelect

10、ric transducers,thermoelectric transducers and photoelectric transducer,etc.Displacementpressurevibration,sound and liquid leveL4.Natural quartz crystals or barium titanate ceramics.5.Temperature at localized points can be determined,They are robust,with a wide operating range from -250C-2?000c.II1位

11、移：displacement 2.thermocouple. 3.resolution.4impedance.5.photovoltaic effect. 6.磁场。7磁电式传感器。8电位计。9稳态响应。10压电效应。IIL 1压电：Piezoelectric materials generate an output charge proportional toapplied force.2磁电：Magnetoelectric transducers employ the principle of a coil moving in a magnetic field.3输出:Input volt

12、age is proportional to the velocity of output motion.4热电:This thermoelectric effect is widely used in temperature measurement and control system.5光电：The photovoltaic cell is based on the principle of the photovoltaic effect.The success of industry in turning such effective techniques to advantage by

13、 developing low-cost products will determine the impact which optical fibers have on communications.3The telephone systems can be divided into three networks:the local networkwhich ties customers to their respective local switching offices; the trunk network, which interconnects the switching office

14、s; the long-distance network between cities.4.When there are many telephone calls to be carried between points such as switching offices,fiber systems are economically attractive.5.6 无线光学通信7在一对一的基础上8本地线路9铜线10传统通信服务Larger fiber bandwidth, lower loss and more reliable optical sources would make optica

15、l fibers more competitive.II1光纤：optical fiber2.1ight-wave-guide fiber3中:switching office4.wire pair5.Low lossIIILThe present competition （has shifted）the fibers.2.The telephone systems can （be divided）into three networks.3.Benefit t4.inexpensive5compete 6.suggest 7.1oops 8.technology pete lOwire pai

16、rs.IV1研究:Moreovestudies suggest that this may be the case for some tine.2Thus the interoffice trunk network will be the first to benefit from this new technology.3.1n fact, various trunkoriented communications systems are under construction or in operation in many industrialized countries.（Optical f

17、ibers have the advantage of small cable size and weight and immunity to lightning and other electromagnetic interference.5.A few optical fibers data link systems are already on the marketand more are under devel-opment.Exercises 第 6 章I l.what are advantaged of the induction motor?Simplicity, economy

18、 and durability2.Because of their ruggedness and lower cost3.1t is most useful when a high-speed drive is desired.4.Wound-rotor motor5.Cost factor.II1交流:ac motor 2Jnduction 3constant speed. 4singlephase5.continuoiis6直流电动机。7同步电动机。8变速。9便携式工具。10电源6单边:Unilatenil limits are usually used when the distance

19、 between two faces,of the diameter of diameter of a hole or shaft is specified.Exercises 第 4 章I 1 what is the function of a mold?The function of a mod is two respects:imparting the desired shape to the elasticized polymer and cooling the injection molded part,2.What is the mold mainly made up of ?It is basically made up of two sets o