連桿機(jī)構(gòu)作業(yè)文檔資料

1、.1主要問題：未按比例作圖！宜用作圖法，不要用解析法！.24-4 in the revolute four-bar mechanism similar to the one in fig.4-23(b), let lab=60mm, lbc =130mm, ldc=140mm, lad=200mm, and bad=135o.(1) determine the type of the revolute four-bar mechanism. crank-rockerabcdvcf .34-4(2) if the side link ab is a driver and rotates at a

2、 constant speed,(a) find the pressure angle and the transmission angle of the mechanism at that position.abcdvcf .4(b) find the angular stroke max of the link dc. (c) find the crank acute angle between the two limiting positions.(d) calculate the time ratio k .abbccdabcd1121max2180180k.5(e) will any

3、 dead-point occur during the whole cycle of the motion? no.(d) find the maximum pressure angle max and the minimum transmission angle min. min =minmin, min 不能只求min !abcdabcdminmin.6(3) if the side link dc is a driver,(a) find the pressure angle and the transmission angle of the mechanism at that pos

4、ition. abcdfvb .7(b) will any dead-point occur during the whole cycle of the motion? if so, when? yes. 兩位置!(c) find the maximum pressure angle max and the minimum transmission angle min.abccdabcd12max2fv1b.8若dc為原動(dòng)件，圖示兩位置的不是min！.94-5 in the offset slider-crank mechanism shown in fig.4-5, the driver c

5、rank ab rotates at a constant speed. let lab=120mm, lbc=250mm, offset e=60mm, and ab=60o. findabcabe.10(1)the length of stroke h of the slider, (2) the crank acute angle (3) the time ratio k , abbcc1122abeh180180k.11(4) and at that position,(5) max and min.abemaxminabcbc.12 4-6. 在偏置曲柄滑塊機(jī)構(gòu)abc中，曲柄ab為主

6、動(dòng)件。已知：lab=25mm, 偏置量e=10mm， max=30. 求：行程 h以及極位夾角 . ae.13 4-6. 在偏置曲柄滑塊機(jī)構(gòu)abc中，曲柄ab為主動(dòng)件。已知：lab=25mm, 偏置e=10mm， max=30. 求：行程 h以及極位夾角 . baea.14 4-6. 在偏置曲柄滑塊機(jī)構(gòu)abc中，曲柄ab為主動(dòng)件。已知：lab=25mm, 偏置e=10mm， max=30. 求：行程 h以及極位夾角 . =30bacmaxeab.15 4-6. 在偏置曲柄滑塊機(jī)構(gòu)abc中，曲柄ab為主動(dòng)件。已知：lab=25mm, 偏置e=10mm， max=30. 求：行程 h以及極位夾角

7、. =30bacmaxeabbc22.16 4-6. 在偏置曲柄滑塊機(jī)構(gòu)abc中，曲柄ab為主動(dòng)件。已知：lab=25mm, 偏置e=10mm， max=30. 求：行程 h以及極位夾角 . =30hbacmaxeabbbcc1122.174-10 圖示為鉸鏈四桿機(jī)構(gòu)abcd的連桿bc的兩個(gè)位置b1c1 和 b2c2. 構(gòu)件ab是主動(dòng)件。第一位置的壓力角 =0o. 第二位置是肘節(jié)位置。試設(shè)計(jì)之。 bbcc1122.181b2b1cc2ad 固定鉸鏈a 必在b1b2的中垂線上。固定鉸鏈 d必在c1c2的中垂線上。 .19 構(gòu)件ab是主動(dòng)件，且第一位置的壓力角 =0o， 所以 b1c1c1d1b2

8、b1cc2ad.20 構(gòu)件ab是主動(dòng)件，且第一位置的壓力角 =0o， 所以 b1c1c1d1b2b1cc2ad.21 構(gòu)件ab是主動(dòng)件，且第二位置是肘節(jié)位置，所以 a、b2、 c2三點(diǎn)共線1b2b1cc2ad.22 構(gòu)件ab是主動(dòng)件，且第二位置是肘節(jié)位置，所以 a、b2、 c2三點(diǎn)共線1b2b1cc2ad.23.24.254-14在偏置曲柄滑塊機(jī)構(gòu)abc中，當(dāng)曲柄ab從第1位置逆時(shí)針轉(zhuǎn)動(dòng)100o 到達(dá)第2位置時(shí)，滑塊鉸鏈c將從 c1 移動(dòng)到c2 . 當(dāng)曲柄ab從第2位置逆時(shí)針轉(zhuǎn)動(dòng)100o 到達(dá)第3位置時(shí)，滑塊鉸鏈c將從 c2 移動(dòng)到c3 . 求鉸鏈b的第3個(gè)位置b3.ac123cc.26 在第

9、一位置，構(gòu)件ab上必有一直線為豎直狀態(tài)，如ae1。作e1ae2=100， e2ae3=100，得e2和e3點(diǎn)。故abe為運(yùn)動(dòng)已知構(gòu)件。ac123cce12e3e.27 b為待定活動(dòng)鉸鏈點(diǎn)。abe是待定活動(dòng)鉸鏈點(diǎn)b所聯(lián)結(jié)的運(yùn)動(dòng)已知構(gòu)件，選為參考系。c是待定活動(dòng)鉸鏈點(diǎn)b所聯(lián)結(jié)的運(yùn)動(dòng)未知構(gòu)件bc上的運(yùn)動(dòng)已知點(diǎn)，選為圓周點(diǎn)。圓周點(diǎn)c相對(duì)于參考系abe的相對(duì)軌跡是圓，圓心是b。a2cb2.28ae1c1 、ae2c2和ae3c3分別代表c點(diǎn)相對(duì)于ae的第一、第二和第三個(gè)位置。ac123cce12e3e.29作ae3c1ae1c1， ae3c2ae2c2，得c1 點(diǎn)和c2點(diǎn)。ac123ccc2c11e2e

10、e3.30作ae3c1ae1c1， 且字母旋向相同，得c1 點(diǎn)。ac123cc1c1ee3.31ae3c1ae1c1， 但字母旋向不相同。ac123cc1c1ee3.32ae3c1ae1c1， 但字母旋向不相同。ac123cc1ee31c.33 作c3c2和c2c1的中垂線，交點(diǎn)就是待定活動(dòng)鉸鏈點(diǎn)b的第三個(gè)位置點(diǎn)b3。不是b1或b2 ！2c1e1e3c2c3cae1c23b.34 作b2ab3=100， b1ab2=100， 得b2和b1點(diǎn)。ac123ccb1bb23.35檢驗(yàn)運(yùn)動(dòng)未知構(gòu)件bc的桿長(zhǎng)是否定長(zhǎng)：b1c1=b2c2=b3c3。ac123ccb1bb23.364-17 在鉸鏈四桿機(jī)構(gòu)

11、abcd中, ab是主動(dòng)件。機(jī)構(gòu)的第1位置是死點(diǎn)位置。求鉸鏈b的第2個(gè)位置b2。accdee1122.37 b是待定活動(dòng)鉸鏈。bce是參考構(gòu)件。a是圓周點(diǎn)。accdee1122.38ac1e1和ac2e2分別代表a點(diǎn)相對(duì)于ce的第一和第二個(gè)位置。accdee1122.39作a2c1e1ac2e2，得a2點(diǎn)。accdee1122a2.40作aa2的中垂線，b1在此中垂線上。accdee1122a2b1.41因ab為原動(dòng)件且機(jī)構(gòu)第一位置為死點(diǎn)，所以b1點(diǎn)在dc1的延長(zhǎng)線上。aa2的中垂線與dc1的延長(zhǎng)線交于b1。accdee1122a2b1.42去掉輔助線后。機(jī)構(gòu)的第一個(gè)位置。accdee1122

12、b1.43作b2c2e2b1c1e1 ，得b2點(diǎn)。accdee1122b1b2.44檢驗(yàn)運(yùn)動(dòng)未知構(gòu)件ab的桿長(zhǎng)：ab1=ab2。accdee1122b1b2.45全部作圖線條accdee1122a2b1b2.46aecc11224-18 在偏置曲柄滑塊機(jī)構(gòu)abc中，c1 是滑塊的左極限位置。求b1。.47aecc1122 b是待定活動(dòng)鉸鏈。bae是參考構(gòu)件。c是圓周點(diǎn)。.48aecc1122因c1為滑塊的左極限位置，所以b1點(diǎn)在ac1連線上。.49aecc1122ac1e1和ac2e2分別代表c點(diǎn)相對(duì)于ce的第一和第二個(gè)位置。.50aecc11222c 作ac2e1ac2e2，且字母旋向相同，

13、得c2 .51ac2”e1ac2e2，但字母旋向不相同。aecc11222c1b2c .52aecc11222c 作ac2e1ac2e2，且字母旋向相同，得c2 .53aecc11222c作c1c2的中垂線與ac1交于待定活動(dòng)鉸鏈點(diǎn)b的第一個(gè)位置點(diǎn)b1。.54機(jī)構(gòu)的第一個(gè)位置ab1c1。aecc11222c1b.55去掉輔助線后。aecc11221b.56作ab2e2ab1e1 ，得b2點(diǎn)。aecc11221b2b.57檢驗(yàn)運(yùn)動(dòng)未知構(gòu)件bc的桿長(zhǎng)：b1c1=b2c2。aecc11221b2b.58aecc1122 b是待定活動(dòng)鉸鏈。bae是參考構(gòu)件。c是圓周點(diǎn)。.59有人將ae1c2拿來轉(zhuǎn)。a

14、ecc1122.604-20 在偏置曲柄滑塊機(jī)構(gòu)abc中，第1位置是滑塊的左極限位置。abbff1122.61c是待定活動(dòng)鉸鏈. 滑塊是參考構(gòu)件. b是圓周點(diǎn).abbff11221c2c.62 因?yàn)榈?位置是滑塊的左極限位置，所以，c1在b1a的延長(zhǎng)線上。abbff11221c.63作b1b1=f1f2，得b1點(diǎn)。abbff11221b1c.64作b2b1的中垂線，交b1a的延長(zhǎng)線于待定活動(dòng)鉸鏈點(diǎn)c的第一個(gè)位置點(diǎn)c1。abbff11221b1c.65機(jī)構(gòu)第一個(gè)位置ab1c1abbff11221b1c.66作c1c2=f1f2，得c2點(diǎn)。abbff11221b1c2c.67檢驗(yàn)運(yùn)動(dòng)未知構(gòu)件bc的

15、桿長(zhǎng)：b1c1=b2c2。 設(shè)計(jì)完畢！abbff11221b1c2c.68若要求滑塊停在第2個(gè)位置，abbff1122b1.69若要求滑塊停在第2個(gè)位置，abbff1122c2b1.70若要求滑塊停在第2個(gè)位置，abbff1122c2b1.71若要求滑塊停在第2個(gè)位置，abbff1122c1c21b.72若要求滑塊停在第1個(gè)位置，abbff1122c1b2.73若要求滑塊停在第1個(gè)位置，abbff1122c1b2作b2b2=f2f1，得b2點(diǎn)。.74作b1b2的中垂線，交b1a的延長(zhǎng)線于待定活動(dòng)鉸鏈點(diǎn)c的第一個(gè)位置點(diǎn)c1。abbff1122c1b2.75導(dǎo)軌是水平的。機(jī)構(gòu)的第一個(gè)位置點(diǎn)ab1c

16、1。abbff1122c1b2.76作c1c2=f1f2，得c2點(diǎn)。abbff1122c1b2c2.77檢驗(yàn)運(yùn)動(dòng)未知構(gòu)件bc的桿長(zhǎng)：b1c1=b2c2。abbff1122c1b2c2.784-26 design a crank-rocker mechanism similar to the one in fig.4-27 that will give a k value of 1.2 with an angular stroke of 45o for the rocker dc, from a constant input speed crank ab. the length of the r

17、ocker dc is 100mm. check that the minimum transmission angle min is larger than 40o. =(k-1)/(k+1)*180o=(1.2-1)/(1.2+1)*180o =16.36o.79 任取d。 ldc=100mm, c1dc2=4545dc1c2.80 c1pc1c2, c1c2p=90 -16.36=73.6416.3645pdc1c2.81 以c2p為直徑作圓。16.3645pdc1c2.82 在圓周上任取一點(diǎn)為a，則c1ac2=16.3616.3645pdac1c2.83 lab= (ac2-ac1)/

18、2 lbc=(ac2+ac1)/216.3645pdab1b2c1c2.84 檢驗(yàn) min45, 注意： ac2d min p16.36db4bb1ba3245minc13cc24.854-28 in an offset slider-crank mechanism, the offset e is 20mm. the coefficient k of travel speed variation is to be 1.3. the working stroke h of the slider is to be 50mm. design the offset slider-crank mech

19、anism 00011.3 118018023.511.3 1kk.86根據(jù)h定c1和c2cc12mh.87根據(jù)滑塊行程h和作等腰三角形oc1c2.cc12mh90 -2.88以o為圓心，作圓.cc12mh90 -2.89acce12mh90 -2 作與導(dǎo)路距離e的平行線，與圓交于固定鉸鏈a.90顯然，c1ac2.acce12mh90 -2 測(cè)量ac1和ac2。.91 a= (ac2-ac1)/2 b=(ac2+ac1)/2abbccabe1122mh90 -2.92-.934-2 determine the type of the linkage and the type of the tw

20、o side links ab and dc (crank or rocker) according to the grashof criterion. can the coupler bc rotate 360o with respect to the frame (yes or no)?bd.94bdtype oflinkagecan bcrotate 360type ofabtype ofdclablllbcdcad45 506020203570902045709080 20456040302035.95bdtype oflinkagecan bcrotate 360type ofabt

21、ype ofdclablllbcdcad45506020203570902045709080 20456040302035dou. ccrankcrankyesdou. rc-rdou. rc-rrockercrankrockerrockerrockerrockerrockercranknonoyesno.964-3 in a revolute four-bar linkage abcd, lbc=100mm, ldc =80mm, lad=110mm. (1)find the range of the values for the length lab of link ab if the l

22、inkage is either (a) a crank-rocker mechanism with crank ab, or (b) a double-rocker mechanism. (2) can the linkage be a double-crank mechanism by choosing lab suitably? why?abcd.974-7 in the double-crank linkage abcd shown in fig.4-1(b), lab=80mm, lbc=180mm, ldc=230mm, lad=200mm. the driver bc rotat

23、es at a constant speed. find the minimum transmission angle min of the linkage.b2c3d41a.984-8 according to the data in problem 4-3, find the range of values for the driving crank ab if the linkage is to be a crank-rocker mechanism and the minimum transmission angle min is larger than 50o. compare th

24、e result with that in problem 4-3(1a).994-9 the crank-rocker mechanism shown in fig.4-31 has no quick-return characteristics. prove that the lengths of links of the linkage satisfy the following equation: (lab)2 + (lad)2 =(lbc)2 + (ldc)2admax=0bbcc1122.1004-11 design a crank-rocker mechanism abcd to

25、 move a line ef on the coupler bc from position e1f1 to position e2f2 and then to position e3f3. xa=0. ya=0. xd=100mm. yd=0. xe1=2.18mm. ye1= -15.1mm. xe2= -3.19mm. ye2=-56.8mm. xe3=67.5mm. ye3= -32.8mm. e1f1=61.7. e2f2=73.4. e3f3=108.5. lef=125mm. find the required moving revolute centres b1 and c1

26、 on the coupler.adeeefff112233.1014-12 design a revolute four-bar linkage abcd so that a point e on the coupler bec will passthrough the three points, e1, e2 and e3. b1、a and d have been specified. find the first position c1 of the moving revolute center c. b332beae2b1d1e.102作e2b2=e1b1, e3b3=e1b1, 得

27、b2和b3點(diǎn)。故be是運(yùn)動(dòng)已知構(gòu)件。bbd12b3e13ee2a.103c為待定活動(dòng)鉸鏈點(diǎn)。bec運(yùn)動(dòng)已知，故bec是待定活動(dòng)鉸鏈點(diǎn)c所聯(lián)結(jié)的運(yùn)動(dòng)已知構(gòu)件，選為參考系。d是待定活動(dòng)鉸鏈點(diǎn)c所聯(lián)結(jié)的運(yùn)動(dòng)未知構(gòu)件上的運(yùn)動(dòng)已知點(diǎn)，選為圓周點(diǎn)。 注意：雖然ab也是運(yùn)動(dòng)已知構(gòu)件，但不應(yīng)選ab為參考系。ad1ec1b1.104de1b1 、de2b2和de3b3分別代表圓周點(diǎn)d點(diǎn)相對(duì)于參考系be的第一、第二和第三個(gè)位置。abbd12b3e13ee2.105作b1e1d2b2e2d，b1e1d3b3e3d，使b2e2、b3e3 與e1b1重合，得d2點(diǎn)和d3點(diǎn)。bd2b3e13ee2d2d3a1b.106作

28、dd3和d3d2的中垂線，交點(diǎn)就是待定活動(dòng)鉸鏈點(diǎn)c的第一個(gè)位置點(diǎn)c1。不是c2 或c3bd2b3e13ee2d2d3c1ab1.107作b2e2c2b1e1c1， b3e3c3b1e1c1 ，得c2和c3點(diǎn)。bd2b3e13ee2c1ab12cc3.108檢驗(yàn)運(yùn)動(dòng)未知構(gòu)件dc桿長(zhǎng)：dc1=dc2=dc3。bd2b3e13ee2c1c23cb1a.109不是檢驗(yàn)ab桿或be桿是否定長(zhǎng)！bd2b3e13ee2c1c23cb1a.1104-13. in a revolute four-bar linkage abcd, as the driver side link ab rotates from

29、position 1 to position 2, the other side link dc rotates 24.6o counter-clockwise. as the link ab goes from position 2 to position 3, the link dc rotates 39.3o counter-clockwise. lab= 50mm and lad=100mm. synthesize the linkage graphically.abdbb12350100.111 在第一位置，搖桿dc上必有一直線為豎直狀態(tài)，如de1。作e1de2=24.6， e2de

30、3=39.3，得e2和e3點(diǎn)。 dce是運(yùn)動(dòng)已知構(gòu)件。abdbb12350100e1ee23.112 c為待定活動(dòng)鉸鏈點(diǎn)。dce是待定活動(dòng)鉸鏈點(diǎn)c所聯(lián)結(jié)的運(yùn)動(dòng)已知構(gòu)件，選為參考系。b是待定活動(dòng)鉸鏈點(diǎn)c所聯(lián)結(jié)的運(yùn)動(dòng)未知構(gòu)件上的運(yùn)動(dòng)已知點(diǎn)，選為圓周點(diǎn)。圓周點(diǎn)b相對(duì)于參考系dce的相對(duì)軌跡是圓，圓心是b。 注意： 雖然ab也是運(yùn)動(dòng)已知構(gòu)件，但不應(yīng)選ab為參考系。adb2c2.113de1b1 、de2b2和de3b3分別代表b點(diǎn)相對(duì)于de的第一、第二和第三個(gè)位置。abdbb12350100e1ee23.114作de1b2de2b2，de1b3de3b3，得b2點(diǎn)和b3點(diǎn)。abdbb12350100e

31、1b23bee23.115作b1b2和b2b3的中垂線，交點(diǎn)就是待定活動(dòng)鉸鏈點(diǎn)c的第一個(gè)位置點(diǎn)c1。b2b350ab2d100b1b31c.116作c1dc2=24.6， c2dc3=39.3，得c2和c3點(diǎn)。abdbb12350100c1cc23.117檢驗(yàn)運(yùn)動(dòng)未知構(gòu)件bc的桿長(zhǎng)：b1c1=b2c2=b3c3。abdbb12350100c1cc23.1184-15 in an offset slider-crank mechanism, a point f on the slider will displace from point f1 to point f2 when the crank

32、 ab rotates from position ab1 to position ab2. as the crank ab rotates from position ab2 to position ab3, the point f displaces from point f2 to point f3. design the offset slider-crank mechanism.abbbfff112233.119 c為待定活動(dòng)鉸鏈點(diǎn)?；瑝K是待定活動(dòng)鉸鏈點(diǎn)c所聯(lián)結(jié)的運(yùn)動(dòng)已知構(gòu)件，選為參考系。b是待定活動(dòng)鉸鏈點(diǎn)c所聯(lián)結(jié)的運(yùn)動(dòng)未知構(gòu)件bc上的運(yùn)動(dòng)已知點(diǎn)，選為圓周點(diǎn)。abf111ccc23f

33、3f2.120 在第一位置，運(yùn)動(dòng)已知構(gòu)件滑塊上必有一直線為豎直狀態(tài)，如e1f1。作e2f2=e3f3= e1f1 ，得e2和e3點(diǎn)。abbb1231e1f2e2f3e3f.121e2b2f2和e3b3f3分別代表b點(diǎn)相對(duì)于ef的第二和第三個(gè)位置。abbb1232e1e3e2f1f3f.122作e1f1b2e2f2b2，e1f1b3e3f3b3，得b2點(diǎn)和b3點(diǎn)。abbb1232e1e3e2f1f3fb32b.123作b1b2和b2b3的中垂線，交點(diǎn)就是待定活動(dòng)鉸鏈點(diǎn)c的第一個(gè)位置點(diǎn)c1。不是c2或c3 ！abbbfff112233b32b1c.124作c1c2=f1f2， c1c3=f1f3，

34、得c2和c3點(diǎn)。abbb1231ccc23f1f2f3.125檢驗(yàn)運(yùn)動(dòng)未知構(gòu)件bc的桿長(zhǎng)：b1c1=b2c2=b3c3。abbb1231ccc232f1f3f.1264-16 moving revolute centre b is on the line cp. design this offset slider-rocker mechanism abcacppc1122.127designed offset slider-rocker mechanism abc. c1b1=c2b2, and ab1=ab2, acppc11222b1.128revolute b is umrc. link

35、 cp is the reference link. point a is the circumference point.acppc11222b1.1294-16 moving revolute centre b is on the line cp. design this offset slider-rocker mechanism abcacppc1122.130ac1p1 represents position relationship between a and cp at the first instant.acppc1122.131ac2p2 represents positio

36、n relationship between a and cp at the second instant.acppc1122.132constructing a1c2p2ac1p1, we get points a1. acppc1122a.133a and a1 are two positions of a relative to reference link cp when cp is stationary at c2p2.acppc1122a.134constructing the middle-normal of aa1.b2 must be located on the middl

37、e-normal.acppc1122a.135the intersection between the mid-normal and c2p2 is the second position b2 of the umrc b.acppc1122a2b.136constructing c1b1=c2b2, we get points b1.acppc1122a2b1.137last, the length of the undetermined link ab must be checked, i.e., ab1=ab2.acppc1122a2b1.138designed offset slide

38、r-rocker mechanism abc. c1b1=c2b2, and ab1=ab2, acppc11222b1.1394-19 in a crank-rocker linkage abcd, side link ab is the driver. at the first position of the linkage, the pressure angle of the linkage is zero. position dc2 is one of the limit positions of the rocker. accd12.140因?yàn)閍b為原動(dòng)件, 且機(jī)構(gòu)第一位置的壓力角=

39、0, 所以b1c1c1d. 不是ab1b1c1！accd12b1.141又因?yàn)閏2d為搖桿cd的一個(gè)極限位置, 所以ab2c2三點(diǎn)共線。因此bc和cd均為運(yùn)動(dòng)已知構(gòu)件。accd12b1b2.142b is umrc. bc is reference link. a is circumference point.accd12b1b2.143a點(diǎn)相對(duì)于bc的第一和第二個(gè)位置。accd12b1b2.144因a點(diǎn)在c2b2延長(zhǎng)線上, 故在c1b1延長(zhǎng)線上截取c1a2=c2a，得a2點(diǎn)。accd12a2b1b2.145作aa2的中垂線與c1b1交于待定活動(dòng)鉸鏈點(diǎn)b的第一個(gè)位置點(diǎn)b1。accd12a2b1

40、b2.146 機(jī)構(gòu)的第一個(gè)位置accd12a2b1b2.147截取b2c2=b1c1 ，得b2點(diǎn)。accd12a2b1b2.148檢驗(yàn)運(yùn)動(dòng)未知構(gòu)件ab的桿長(zhǎng)：ab1=ab2。accd12a2b1b2.1494-21 when the wheel of the landing mechanism in an airplane is at its lowest position, links bc and cd are collinear. suppose the position of revolute c is unknown. find the position of the revolut

41、e c on line dcb so that the link ab will rotate 90 counter-clockwise when the link dc rotates 101 clockwise. the known dimensions are: xa=0, ya=0, xd=103mm, yd=23.55mm, and lab=55.85mm.acdb.150b1ab2=90, c1dc2=60。由題意知, 兩連架桿ab 和dc均為運(yùn)動(dòng)已知構(gòu)件。c為待定活動(dòng)鉸鏈點(diǎn)。bc為運(yùn)動(dòng)未知構(gòu)件。dc是待定活動(dòng)鉸鏈點(diǎn)c所聯(lián)結(jié)的運(yùn)動(dòng)已知構(gòu)件，選為參考系。b是待定活動(dòng)鉸鏈點(diǎn)c所聯(lián)結(jié)的運(yùn)

42、動(dòng)未知構(gòu)件bc上的運(yùn)動(dòng)已知點(diǎn)，選為圓周點(diǎn)。ad1cb1b2c2.151因b1點(diǎn)在dc1延長(zhǎng)線上, 故在dc2延長(zhǎng)線上截取db1=db1，得b1點(diǎn)。ad1cb1c2b21b.152作b2b1的中垂線與dc2交于待定活動(dòng)鉸鏈點(diǎn)c的第二個(gè)位置點(diǎn)c2。ad1cb1c2b21b.153截取dc1=dc2 ，得c1點(diǎn)。ad1cb1c2b21b.154檢驗(yàn)運(yùn)動(dòng)未知構(gòu)件bc的桿長(zhǎng)：b1c1=b2c2。ad1cb1c2b2.1554-22 in a revolute four-bar linkage abcd, crank ab is a driver. the first position of the rocker is one of its two limiting positions. find the second position c2 of the rev