问题 问答题 论述题

主轴变速箱设计中,为什么要遵循“前多后少”的原则?

答案

参考答案:

(1)主变速传动系统从电动机到主轴,通常为降速传动。接近电动机传动件转速较高,根据公式可知,传动的转矩M较小,尺寸小些;

(2)反之,靠近主轴的传动件转速较低,传递的转矩较大,尺寸较大。

(3)因此,在拟定主变速系统时,尽可能将传动副较多的变速组安排在前面,将传动副较少的变速组安排在后面,使主变速传动系统中更多的传动件在高速范围内工作,尺寸小些,以便节省变速箱的造价,减少变速箱的外形尺寸。

多项选择题
完形填空
A gentle wind blew through Jennifer’s hair. The golden red sun was  36  . She was on the beach, looking up at the ball. She was amazed by its   37  , deep red in the middle,  38  fading into yellow. She could hear nothing but the  39  and the seagulls flying up above in the sky.
The atmosphere  40  her. After all she had been through, this is what she   41  . “It’s getting late,”she thought,“I must go home, my parents will be    42  where I am.”She wondered how her parents would react, when she got home after the three days she was  43  .
The sun had set by now and it was getting  44 . She tried to imagine having her favorite  45 on until she saw her front door. It seemed different.   46  had taken care of the outside garden for days. She was   47  : her father was usually so strict about keeping everything clean and tidy, and  now… It all seemed    48  . She couldn’t understand what was going on.She entered the   49 . First,she went into the kitchen where she saw a(n)  50  written by her father. It said:“Dear Ellen,there is some coffee ready,I went   51  .” Ellen was her mother but-where was she? On the right side of the hallway was her    52   room. She went in. Then she saw her mother,lying on the bed sleeping. Her
 53  looked so tired,as if she hadn’t   54   for days. She was really pale. Jenny just fell asleep beside her. When Jennifer woke up she found something  55  . She was in her cozy bed in her nightclothes.
It felt so good being back home. Suddenly she heard a voice.“Are you feeling better now, dear? You know you got us very, very scared.”
小题1:
A.risingB.settingC.shiningD.smiling
小题2:
A.shapeB.shadowC.sizeD.color
小题3:
A.quicklyB.partlyC.softlyD.probably
小题4:
A.wavesB.boatsC.treesD.sands
小题5:
A.relaxedB.puzzledC.disappointedD.interrupted
小题6:
A.understoodB.consideredC.neededD.regretted
小题7:
A.discussingB.findingC.askingD.wondering
小题8:
A.aliveB.asleepC.missingD.hardworking
小题9:
A.sunnyB.warmC.coldD.cloudy
小题10:
A.glassesB.hatC.skirtD.jacket
小题11:
A.SomebodyB.NobodyC.MotherD.Father
小题12:
A.shockedB.scaredC.exhaustedD.comforted
小题13:
A.beautified B.rearrangedC.desertedD.destroyed
小题14:
A.gardenB.bedroomC.yardD.house
小题15:
A.bookB.noteC.articleD.poster
小题16:
A.lookingB.workingC.fishingD.sightseeing
小题17:
A.ownB.parents’C.sister’sD.brother’s
小题18:
A.gestureB.bodyC.faceD.eyes
小题19:
A.studiedB.sleptC.exercisedD.moved
小题20:
A.differentB.newC.preciousD.dangerous