Электрические элементы
план-конспект занятия по английскому языку (11 класс) по теме

Main Structural Elements

1. Read the text:

    A direct-current machine consists of  two main parts, a stationary part, usually called the stator, designed mainly for producing a magnetic flux, and a rotating part, called the armature or the rotor. The stationary and rotating parts should be separated from each other by an air-gap. The stationary part of a d.c. machine consists of main poles, designed to create the main magnetic flux; commutating poles interposed between the main poles; and a frame. It should be noted here that sparkles operation of the machine would be impossible without the commutating poles. Thus, they should ensure spark less operation of the brushes at the commutator.

    The main pole consists of a laminated core the end of which facing the armature carries a pole shoe and a field coil through which direct current passes. The armature is a cylindrical body rotating in the space between the poles and comprising a slotted armature core, a winding inserted in the armature slots, a commutator, and a brush gear.

   The frame is the stationary part of the machine to which are fixed the main and commutating poles and by means of which the machine is bolted to its bedplate. The ring shaped portion which serves as the path for the main and commutating pole fluxes is called the yoke. End-shields or frame-heads which carry the bearings are also attached to the frame.

   Of these main structural elements of the machine the yoke, the pole cores, the armature core and the air-gap between the armature core and the pole core are known to form the magnetic circuit while the pole coils, the armature windings, the commutator and brushes should form the electric circuit of the machine.

2. Translate the following phrases, using the given variants of translation:

    to consist - состоять : to consist of a stationary part and a rotating part;

   separated – отдельный, изолированный : the stationary and rotating parts

                      should be separated from each other by an air gap;

   to serve – служить в качестве чего-либо  : the ring shaped portion or yoke

                   serves as a path for the main  and commutating pole fluxes.

3. Arrange synonyms in pairs and memorize them:

    a) to consist of; to be separated from; to create; to be interposed between; to  pass; to rotate;

    b) to be divided with; to produce; to introduce into; to permeate; to roll; to revolve; to comprise.

4. Join the beginning and the ends:

             Beginnings

   1. The stationary parts of a d.c. machine are …

   2. The two main parts of a direct current machine are …

   3. The main pole consists of …

             Ends

1. a laminated core the end of which carries a pole shoe and a field coil.
2. main poles, commutating poles and a frame.
3. a stationary part or stator and a rotating part, called the armature or the rotor.

5. Write out the names of the machine parts and describe their operational characteristics.