问题 问答题 简答题

下图所示为料仓式上料装置元件—隔料器的基本型式,试分析图示各类隔料器的主要特点。

答案

参考答案:

(1)a、b所示为上料器兼作隔料器。构造简单,隔料时料槽内的所有毛坯都作用在上料器的上表面,运动阻力大,易磨损。

(2)c、d所示为杆式隔料器。每往复运动一次,从料槽中分离出一个毛坯。适用于中等生产率情况,当生产率更高时,往复时间短,毛坯可能因惯性进不了隔料位置。

(3)e、f所示为鼓轮式隔料器。旋转一周可送出较多毛坯,能在低速下平稳工作,避免毛坯因受冲击而损坏。F所示隔料器可使装在两个送料槽的毛坯按一定次序交替送到下面的送料槽。

阅读理解

If you wish to become a better reader, here are four important points to remember about rate, or speed, of reading:

1. Knowing why you are reading—what you are reading to find out—will often help you to know whether to read rapidly or slowly.

2. Some things should be read slowly throughout. Examples are directions for making or doing something, arithmetic problems, science and history books, which are full of important information. You must read such things slowly to remember each important step and understand each important idea.

3. Some things should be read rapidly throughout. Examples are simple stories meant for enjoyment, news, and letters from friends, items, or bits of news from local, or hometown, paper, telling what is happening to friends and neighbors.

4. In some of your readings, you must change your speed from fast to slow to fast, as you go along. You need to read certain pages rapidly and then slow down and do more careful readings when you come to important ideas which must be remembered.

48. According to the passage, your reading speed depends on ________.

A. whether the reading material is easy or difficult

B. what you are reading

what your purpose in reading something is

D. both B and C

49. If one wants to be relaxed by reading, one should take up ________.

A. a story book             B. a book on science and technology

C. news, letters from friends D. some material full of information

50. Which of the following readings should you read slowly and carefully?

A. Fairy tales.                   B. Aesop’s Fables.

C. Directions for use of a machine D. An evening paper.

51. Which of the following can best express the main idea of the passage?

A. How to decide your reading speed.  B. How to raise your reading speed.

C. How to improve your reading skills.  D. How to choose your reading materials.

单项选择题