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1、<p><b>  翻譯部分</b></p><p><b>  英文原文</b></p><p>  Auto-discharging System for Jigging Machine Based on SRM</p><p>  Abstract-This paper introduces an auto

2、-discharging system for jigging machine based on switched reluctance motor (SRM). In this system, SRM is used to replace the traditional asynchronous motor. The hardware system, controller and software design methods are

3、 discussed in this paper. AT89C51 is taken as the core component of the speed regulation controller for SMR and works with other peripheral circuits to realize effective control on motor. The experiment shows that auto-d

4、ischarging system for </p><p>  Keywords:Jigging machine, auto-discharge system; switched reluctance motor</p><p>  1. INTRODUCTION</p><p>  The jigging machine is a kind of mechani

5、cal mineral sorting equipment and occupies an important position in the production of the large modem coal preparation plant. However, the automation level of jigging machine has been out-dated. The backward control mode

6、 in jigging coal preparation restricts the product quality, separation efficiency and process ability. One of the reasons is the lower efficiency of the motor which is used commonly in discharging system for jigging mach

7、ine. How to improve </p><p>  Switched reluctance motor (SRM) with better start characteristics is suitable for starting frequently in adverse environmental condition, high temperature and even strong</p&

8、gt;<p>  vibration conditions and keeps higher efficiency. Based on these characteristics, we use switched reluctance motor instead of the traditional asynchronous motor to develop</p><p>  auto-di

9、scharging system for jigging machine based on SRM. The experiment shows that auto-discharging system for jigging machine based on SRM is feasible and can play an important role in stabilizing clean coal ash content, redu

10、cing clean coal loss, improving product quality and separation efficiency.</p><p>  II. CONSTITUTION OF SPEED-REGULATION SYSTEM FOR SWITCHED RELUCTANCE MOTORS</p><p>  The speed-regulation syste

11、m for switched reluctance motor is composed of SRM, power converter, controller and detector, as shown in Figure 1.</p><p>  Figure. 1 The structure of the SRM speed-regulation system</p><p>  1

12、) Switched reluctance motor</p><p>  Switched reluctance motor is the key component of SRM speed-regulation system.</p><p>  2) Power converter</p><p>  The power converter is a cir

13、cuit device that is used to drive SRM and provide power for SRM. The on and off status of power switch of power converter are controlled reasonably to complete speed regulating. The cost of power converter accounts for a

14、 large proportion in whole SRM speed-regulation system, thus selecting and designing suitable power converter is one of key factors that improve performance-price ratio of SRM speed-regulation system.</p><p>

15、;  3) Controller</p><p>  Controller is the centrum of system and will play an important role in the system. The function of controller is, according to actual system running status, to deal with external in

16、put instruction, speed feedback signal and feedback information of current sensor and position sensor and to control the working state of main switch device in power converter, thus, realizing the control of switched rel

17、uctance motor running status, satisfYing the running requirements.</p><p>  4) Detector</p><p>  In order to enable switched reluctance motor to run normally, the corresponding phase winding mus

18、t be conductive when the rotor goes to certain position and every phase windings should be switched correctly all the time. Otherwise, motor not only can not operate as per requirement, but also the phenomena such as mot

19、or reversion, stop or rotating random may occur. In order to obtain instantaneous position of rotor while motor runs, the angle displacement sensor must be installed within motor to o</p><p>  III. USE DESIG

20、N OF CONTROLLER FOR SRM SPEED-REGULATION SYSTEM</p><p>  The method of combining hardware circuit and singlechip computer is adopted in the design of controller for SRM speed-regulation system. Hardware circ

21、uit takes charge fast regulation task and single-chip computer completes the complex functions such as logic and parameter setting. AT89C51 single-chip computer is used as the core component of controller, in addition, o

22、ther control circuits such as position detector, current and voltage detector, overcurrent protection, over voltage protection, an</p><p>  Figure.2 The hardware structure of the system controller</p>

23、<p>  The AT89C51 single-chip computer is the key part of controller and its function is comparing the given value of external rotate speed with actual value of motor speed, then</p><p>  calculating c

24、ontrollable variables (mostly including current chopping basis Ig and motor winding firing angle θon ) according to pre-established PID regulating formula, lastly, based on the external operation requirements (rotating c

25、lockwise or counter-clockwise) and the wave shape of position sensor to decide phase output signal. Moreover, the single-chip computer completes also some display functions, for instance, over voltage, low voltage, over

26、loading and system status and so on.</p><p>  (1) Position sensor signal input circuit is the role of the motor position sensor signal waveform input is provided to the microcontroller, and also both isolati

27、on protection function. Single chip microcomputer according to the circuit provides the waveform can be identified motor rotor position so as to determine the corresponding output signal, can also be based on the sensor

28、waveform cycle to calculate the practical operation of the motor speed values to PID operations and other functions.</p><p>  (2) Phase interruption circuit function is when the position sensor waveform chan

29、ges state generates an interrupt signal to the microprocessor to provide a phase signal output to prepare.</p><p>  (3) Phase locked frequency multiplier circuit is used to position sensor signal cycle frequ

30、ency. But the computer from accurate in conduction angle and critical angle corresponding to the output signal is broken.</p><p>  (4) A/D conversion and speed circuit which is to be set by the user simulati

31、on speed value through the A/D conversion module conversion to digital quantity input to the computer.</p><p>  (5) Over-voltage and under-voltage protection circuit when the role of the power circuit voltag

32、e exceeds the specified voltage and control the supply voltage is less than the given value to the computer sends out alarm signals from but make the corresponding treatment and protective measures of computer.</p>

33、<p>  (6) External operation circuit of the main role is to user requirements, such as start, stop, forward, inversion, electric, braking, dynamic and interlock control information input to the computer, as well a

34、s with external isolation effect.</p><p>  (7) Reset circuit is mainly divided into: power on reset, manual reset and automatic reset. When a system failure by divided so that its return to a normal state.&l

35、t;/p><p>  (8) Display circuit functions to display the working status of motor speed control system. Mainly a given speed display, the given speed and actual speed synchronization, overload and locked-rotor di

36、splay, over-voltage and under-voltage display, display and power supply display operation.</p><p>  (9) Signal output interface circuit is used to output of the single chip computer corresponding signal outp

37、ut to the external interface circuit so as to interface with MCU isolation effect; steering control circuit's function according to user's operation requirements to determine the motor running steering: the posit

38、ive rotation and the reverse rotation.</p><p>  (10) D/A conversion and low speed chopper circuit is when the motor is running below the low speed region, the controlled variables through the D/A converter c

39、onverts the analog quantity and the winding of the motor to thereby control the actual current value is compared to the motor winding current peak.</p><p>  (11) Current limiting protection circuit when the

40、role of the motor winding current exceeds a rated current value when the output signal so that all the output signal of the phase in the off state, protects the main circuit of large power transistor and the effect of mo

41、tor winding.</p><p>  (12) Logic and circuit is the role of the three signal processing logic and then output to the corresponding push circuit is amplified to drive the power circuit, isolation.</p>

42、<p>  IV. SOFTWARE DESIGN OF CONTROLLER FOR SRM SPEED-REGULATION SYSTEM</p><p>  The programming of controller software uses assembly language of A T89C51 single-chip computer. Modularization design is

43、 adopted to increase readability and portability. For this system, the control software should meet following requirements:</p><p>  1) To assure that motor starts without dead zone and possesses large enoug

44、h start torque to decrease torque pulsating during starting.</p><p>  2) To be capable of realizing motor transition smoothly between two working status, that is, low speed current chopping and high speed an

45、gle position.</p><p>  3) To be able to receive and judge external fault signals and protection signals, to diagnose and display faults and take corresponding prevention measures.</p><p>  4) To

46、 use modularization method in software programming, to generate relationship as few as possible between subroutines and transmit parameters by variables and flags. </p><p>  The software programming includes

47、 main, startup module, running module and phase interrupt module. The flowchart of main program is shown in Figure 3.</p><p>  Figure.3 The hardware structure of the system controller</p><p>  V

48、. AUTO-DISCHARGING SYSTEM FOR JIGGING MACHINE BASED ON SRM</p><p>  A. Constitution of Auto-discharging System for Jigging Machine</p><p>  In order to discharge heavy product in time and contin

49、uously, separate product and keep stable and appropriate coal layer thickness, the modem jigging machines all use auto-discharging devices. The autodischarging device for jigging machine is mainly composed of sieve plate

50、, flashboard, sensors Rump, electromagnetism valve, and hydraulic pressure cylinder. </p><p>  Figure 4 illustrates the structure of auto-discharging device for jigging machine.</p><p>  Figure

51、4. Structure diagram of jigging machine discharging system</p><p>  B. The Application of Switched Reluctance Motor in AutoDischarging System for Jigging Machine</p><p>  The purpose of Auto-dis

52、charging system for jigging machine is to keep stable bed thickness in jigging room by controlling discharge quantity. Stable bed thickness is the important condition that keeps jigging machine in better separation statu

53、s, therefore, strongly attention is paid on the auto-discharging system for jigging machine. The basic control principle of auto-discharging system is that float detects bed thickness in jigging room and then bed thickne

54、ss signal is send to controller, acco</p><p>  Figure 5 illustrates the constitution block diagram of material auto-discharging measurement and control system for jigging machine driven by SRM.</p>&l

55、t;p>  Figure 5. Structure diagram of jigging machine discharging system</p><p>  Experiments show that using SRM to drive jigging machine material discharging device, better fine coal quality can be obtai

56、ned, separating density can be improved and productive effect and capacity are increased.</p><p>  VI. CONCLUSION</p><p>  Starting with the drive source motor of jigging machine material discha

57、rging device, SRM speed regulation control technology is applied to material auto-discharging system. In this system, SRM with better performance is used to replace the traditional asynchronous motor. The characteristics

58、 of switched reluctance motor, such as suitable for starting frequently in adverse environmental condition, high temperature and even strong vibration conditions, are taken full advantage of Therefore, the aut</p>

59、<p><b>  中文譯文</b></p><p>  基于SRM的跳汰機(jī)自動排料系統(tǒng)</p><p>  摘要:本文介紹了一種基于開關(guān)磁阻電機(jī)(SRM)的跳汰機(jī)自動排料系統(tǒng)。在這個系統(tǒng)中,SRM是用來取代傳統(tǒng)的異步電機(jī)。本文還對硬件系統(tǒng)、控制器和軟件的設(shè)計方法進(jìn)行了探討。采用AT89C51作為核心調(diào)速控制的SRM與周邊電路的配合實現(xiàn)對電機(jī)的有效控制。實

60、驗結(jié)果表明,基于SRM的跳汰機(jī)自動排料系統(tǒng)是可行的,在穩(wěn)定潔凈煤灰分、減少潔凈煤損失、提高產(chǎn)品質(zhì)量和分離效率發(fā)揮重要的作用。</p><p>  關(guān)鍵詞:跳汰機(jī),自動排料系統(tǒng),交換磁阻電機(jī)</p><p>  關(guān)鍵字:跳汰機(jī),自動排料系統(tǒng),開關(guān)磁阻電機(jī)</p><p><b> ?、?簡介</b></p><p>  跳

61、汰機(jī)是一種機(jī)械礦物分選設(shè)備,并且在大型規(guī)模的現(xiàn)代化煤礦選煤廠占有重要地位。然而,跳汰機(jī)自動化水平已經(jīng)過時。跳汰選煤的落后控制方式制約著產(chǎn)品質(zhì)量、分離效率和處理能力,原因之一是跳汰機(jī)在排料系統(tǒng)中使用低效率的電機(jī)。如何提高電機(jī)效率對提高選煤效率和穩(wěn)定煤炭洗選產(chǎn)品質(zhì)量有重要的意義。</p><p>  具有更好的起動特性開關(guān)磁阻電動機(jī)(SRM)適合在不利的環(huán)境條件、高溫甚至強(qiáng)烈振動條件下啟動并保持較高的效率。根據(jù)這些特

62、點,我們用開關(guān)磁阻電動機(jī)SMR,而不是傳統(tǒng)的異步電機(jī)系統(tǒng)開發(fā)跳汰機(jī)自動排料系統(tǒng)。實驗結(jié)果表明,基于SRM的跳汰機(jī)自動排料系統(tǒng)是可行的,在穩(wěn)定潔凈煤灰分、減少潔凈煤損失、提高產(chǎn)品質(zhì)量和分離效率可以發(fā)揮重要的作用。</p><p> ?、? 開關(guān)磁阻電機(jī)速度調(diào)節(jié)系統(tǒng)的結(jié)構(gòu)</p><p>  開關(guān)磁阻電機(jī)的速度調(diào)節(jié)系統(tǒng)是由SRM、電力轉(zhuǎn)換器、控制器和檢測器組成,如圖1。</p>

63、<p>  圖1 開關(guān)磁阻電機(jī)速度調(diào)節(jié)系統(tǒng)的結(jié)構(gòu)</p><p><b>  1) 開關(guān)磁阻電機(jī)</b></p><p>  開關(guān)磁阻電機(jī)是開關(guān)磁阻電機(jī)速度調(diào)節(jié)系統(tǒng)的關(guān)鍵。</p><p><b>  2) 功率轉(zhuǎn)換器</b></p><p>  功率轉(zhuǎn)換器是一個為開關(guān)磁阻電機(jī)提供驅(qū)動和電

64、能的電路裝置。依靠功率轉(zhuǎn)換器的開關(guān)狀態(tài)來合理控制完成調(diào)速。功率轉(zhuǎn)換器的成在整個開關(guān)磁阻電機(jī)速度調(diào)節(jié)系統(tǒng)中占很大比重,從而選擇和設(shè)計合適的功率轉(zhuǎn)換器是開關(guān)磁阻電機(jī)速度調(diào)節(jié)系統(tǒng)中提高性價比的關(guān)鍵因素之一。</p><p><b>  3)控制器</b></p><p>  控制器是中樞系統(tǒng)和將起到重要的作用。控制器的功能,根據(jù)實際系統(tǒng)運行狀態(tài),處理外部輸入指令,速度反饋信

65、號,電流傳感器反饋信息和位置傳感器與控制工作狀態(tài)的主要開關(guān)設(shè)備電力轉(zhuǎn)換器,因此,實現(xiàn)控制的開關(guān)磁阻電動機(jī)運行狀態(tài),滿足運行要求。 </p><p><b>  4)檢測器</b></p><p>  為了使開關(guān)磁阻電機(jī)正常運行,相應(yīng)的相繞組轉(zhuǎn)子導(dǎo)電時必須去某些位置和各階段轉(zhuǎn)換繞組應(yīng)正確。否則,電機(jī)不但不能按要求操作,而且可能發(fā)生如電機(jī)反轉(zhuǎn),停止或旋轉(zhuǎn)隨機(jī)的現(xiàn)象。為了獲

66、得在馬達(dá)運轉(zhuǎn)時轉(zhuǎn)子的瞬時位置,角度-位移傳感器必須安裝在電機(jī)轉(zhuǎn)子位置來輸出正確的信息。這也是開關(guān)磁阻電動機(jī)和其它電機(jī)一個很明顯的區(qū)別。</p><p>  III. 開關(guān)磁阻電機(jī)速度調(diào)節(jié)系統(tǒng)使用的控制器</p><p>  采用單片機(jī)和硬件電路相結(jié)合的方法來對開關(guān)磁阻電機(jī)速度調(diào)節(jié)系統(tǒng)進(jìn)行設(shè)計。硬件電路負(fù)責(zé)監(jiān)管任務(wù)而單片機(jī)快速完成復(fù)雜的功能,例如邏輯及參數(shù)設(shè)置。采用AT89C51單片機(jī)作為控

67、制器的核心部件,除此之外,其他控制電路例如位置檢測器、電流和電壓檢測器、過流保護(hù)、過壓保護(hù)、模擬和數(shù)字輸入、輸出電路和顯示電路等也一樣。開關(guān)磁阻電機(jī)速度調(diào)節(jié)系統(tǒng)的控制框圖如圖2所示。</p><p>  圖2 控制系統(tǒng)的硬件結(jié)構(gòu)</p><p>  AT89C51單片機(jī)控制的重要組成部分,它的功能是將給定的外部旋轉(zhuǎn)速度值與電機(jī)速度的實際值進(jìn)行比較,然后根據(jù)之前確定PID調(diào)節(jié)公式計算可控變量

68、(主要包括電流斬波的基礎(chǔ)值Ig和電機(jī)繞組角度θon),最后,基于外部操作要求(旋轉(zhuǎn)時針或逆時針旋轉(zhuǎn))和位置傳感器的波狀決定相應(yīng)的輸出信號。此外,也有一些單片機(jī)完成顯示功能,例如,過電壓、低電壓、超載和系統(tǒng)狀態(tài)等等。</p><p> ?。?)位置傳感器信號輸入電路的作用是將電機(jī)上的位置傳感器信號波形輸入提供給單片機(jī),同時還兼?zhèn)涓綦x保護(hù)作用。單片機(jī)根據(jù)該電路提供的波形可以確定電機(jī)轉(zhuǎn)子的位置從而決定相應(yīng)輸出信號,另外

69、還可以根據(jù)傳感器波形周期計算出電機(jī)實際運行速度值以便進(jìn)行PID運算及其他功能處理。</p><p>  (2)相中斷電路的作用主要是當(dāng)位置傳感器波形狀態(tài)發(fā)生變化時產(chǎn)生中斷信號給單片機(jī)從而為下一相相信號輸出做準(zhǔn)備。</p><p> ?。?)鎖相倍頻電路的作用是將位置傳感器信號周期倍頻。從而是計算機(jī)準(zhǔn)確在導(dǎo)通角和關(guān)鍵角處輸出相應(yīng)的相通斷信號。</p><p> ?。?

70、)A/D轉(zhuǎn)換及轉(zhuǎn)速給定電路是將用戶設(shè)置的模擬轉(zhuǎn)速給定值通過A/D轉(zhuǎn)換模塊變換為數(shù)字量輸入給計算機(jī)。</p><p> ?。?)過壓、欠壓保護(hù)電路的作用是當(dāng)功率電路的電壓超過規(guī)定電壓值和控制電源電壓低于給定值時給計算機(jī)發(fā)出報警信號從而是計算機(jī)做出相應(yīng)處理及保護(hù)措施。</p><p> ?。?)外部操作電路的主要作用是將用戶要求,比如起到、停車、正轉(zhuǎn)、反轉(zhuǎn)、電動、制動、點動及聯(lián)鎖控制信息等輸入

71、給計算機(jī),同時又起到與外部隔離作用。</p><p> ?。?)復(fù)位電路主要分為:上電復(fù)位、手動復(fù)位及自動復(fù)位。當(dāng)系統(tǒng)出現(xiàn)故障是通過分為使其回復(fù)到正常狀態(tài)。</p><p> ?。?)顯示電路的作用是顯示電機(jī)調(diào)速系統(tǒng)的各種工作狀態(tài)。主要有給定轉(zhuǎn)速顯示、給定速度與實際速度同步、過載及堵轉(zhuǎn)顯示、過壓及欠壓顯示、運行顯示及電源顯示等。</p><p> ?。?)相信號輸出

72、接口電路的作用是將單片機(jī)輸出的相應(yīng)相信號輸出給外部接口電路從而起到與單片機(jī)接口隔離的作用;轉(zhuǎn)向控制電路的作用是根據(jù)使用者的操作要求決定電機(jī)運行的轉(zhuǎn)向:正轉(zhuǎn)和反轉(zhuǎn)。</p><p> ?。?0)D/A轉(zhuǎn)換及低速斬波電路的作用是當(dāng)電機(jī)運行低于低速區(qū)域時,將被控變量通過D/A轉(zhuǎn)換器轉(zhuǎn)換成模擬量與電機(jī)繞組的實際電流值進(jìn)行比較從而控制電機(jī)繞組峰值電流。</p><p> ?。?1)限流保護(hù)電路的作用

73、是當(dāng)電機(jī)繞組電流超過額定電流值時輸出信號從而使所有相輸出信號處于關(guān)斷狀態(tài),起到保護(hù)主電路大功率晶體管及電機(jī)繞組的作用。</p><p> ?。?2)邏輯與電路的作用是將上述三者信號進(jìn)行邏輯與處理后輸出至相應(yīng)的推動級電路進(jìn)行放大、隔離來驅(qū)動功率電路。</p><p>  IV. 開關(guān)磁阻電機(jī)速度調(diào)節(jié)系統(tǒng)的軟件設(shè)計</p><p>  AT89C51單片機(jī)軟件編程控制器

74、的使用的是匯編語言。模塊化設(shè)計用于提高文檔的可讀性和可移植性。在該控制系統(tǒng)中,控制軟件應(yīng)滿足以下要求:</p><p>  1)以確保電機(jī)無死區(qū)以及在開始擁有足夠大的啟動力矩降低扭矩脈動啟動過程。</p><p>  2)能實現(xiàn)電機(jī)在兩個工作狀態(tài)平穩(wěn)過渡,即低速電流斬波和高速度的角度位置。</p><p>  3)能夠接收和外部故障信號進(jìn)行判斷和保護(hù)信號,診斷和顯示

75、故障及獲得相應(yīng)的預(yù)防措施。</p><p>  4)在軟件程序中使用模塊化方法,盡量少通過變量和標(biāo)志在子程序和傳遞參數(shù)之間產(chǎn)生關(guān)系。</p><p>  軟件編程包含有主程序,啟動模塊,運行模塊和中斷模塊。主程序流程如圖3。</p><p>  圖3 控制系統(tǒng)的軟件結(jié)構(gòu)</p><p>  V. 基于SRM的跳汰機(jī)自動控制系統(tǒng)</p&g

76、t;<p>  A.跳汰機(jī)自動排料系統(tǒng)的結(jié)構(gòu)</p><p>  為了產(chǎn)品及時和不斷的排放,為獨立的產(chǎn)品保持穩(wěn)定和適當(dāng)?shù)拿簩雍穸?,現(xiàn)代跳汰機(jī)都用自動排料設(shè)備。跳汰機(jī)的自動排料裝置主要由跳汰機(jī)篩板、插板、傳感器、泵、電磁閥、液壓缸組成。</p><p>  圖4介紹了跳汰機(jī)自動排料系統(tǒng)的結(jié)構(gòu)。</p><p>  圖4.跳汰機(jī)排料系統(tǒng)框圖</p&g

77、t;<p>  B.開關(guān)磁阻電機(jī)在跳汰機(jī)自動排料系統(tǒng)中的應(yīng)用</p><p>  跳汰機(jī)自動排料系統(tǒng)的目的是通過控制排放數(shù)量保持床層厚度在跳汰室的穩(wěn)定。床厚度穩(wěn)定是使跳汰機(jī)保持更好分離狀態(tài)的重要條件,因此,需強(qiáng)烈地注意跳汰機(jī)自動排料系統(tǒng)。跳汰機(jī)自動排料系統(tǒng)控制的基本原理是檢測在跳汰室中的浮床厚度,然后跳汰床厚度信號被送去控制器,根據(jù)給定的床厚度和實際反饋床厚度比較,通過控制算法計算來使控制器輸出信號

78、控制流量閥或手推車,從而,控制排放的數(shù)量和穩(wěn)定床厚度。</p><p>  圖5說明了通過開關(guān)磁阻電機(jī)控制的跳汰機(jī)自動排料系統(tǒng)的結(jié)構(gòu)</p><p>  圖5.跳汰機(jī)自動排料系統(tǒng)的結(jié)構(gòu)框圖</p><p>  實驗結(jié)果表明,使用開關(guān)磁阻電機(jī)驅(qū)動跳汰機(jī)物料排放裝置能更好的獲得優(yōu)質(zhì)質(zhì)量煤炭,改善分離密度,提高生產(chǎn)效果和能力。</p><p>&l

79、t;b>  VI.結(jié)論</b></p><p>  從跳汰機(jī)物料排放裝置的驅(qū)動電機(jī)來看,開關(guān)磁阻電動機(jī)調(diào)速控制技術(shù)應(yīng)用在自動排料系統(tǒng)已被接受。 在這個系統(tǒng)中,性能較高的開關(guān)磁阻電機(jī)是用來取代傳統(tǒng)的異步電機(jī)。開關(guān)磁阻電機(jī)的特點,如適合經(jīng)常在不利的環(huán)境條件啟動、高溫、甚至強(qiáng)烈振動條件下,能被充分利用。因此,基于開關(guān)磁阻電機(jī)的跳汰機(jī)自動排料系統(tǒng)是可行的并且可以在穩(wěn)定潔凈煤灰分、減少潔凈煤損失、提高產(chǎn)品

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