Automation technology. Технологии автоматизации. Учебное пособие

READING

READ AND TRANSLATE THE TEXT POWER SOURCE

The developments described above have provided the three basic building blocks of automation: (1) a source of power to perform some action, (2) feedback controls, and (3) machine programming. Almost without exception, an automated system will exhibit all these elements.

An automated system is designed to accomplish some useful action, and that action requires power. There are many sources of power available, but the most commonly used power in today’s automated systems is electricity. Electrical power is the most versatile, because it can be readily generated from other sources (e.g., fossil fuel, hydroelectric, solar, and nuclear) and it can be readily converted into other types of power (e.g., mechanical, hydraulic, and pneumatic) to perform useful work. In addition, electrical energy can be stored in high-performance, long-life batteries.

The actions performed by automated systems are generally of two types:

(1) processing and (2) transfer and positioning. In the first case, energy is applied to accomplish some processing operation on some entity. The process may involve the shaping of metal, the molding of plastic, the switching of electrical signals in a communication system, or the processing of data in a computerized information system. All these actions entail the use of energy to transform the entity (e.g., the metal, plastic, electrical signals, or data) from one state or condition into another more valuable state or condition. The second type of action—transfer and positioning—is most readily seen in automated manufacturing systems designed to perform work on a product.

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In these cases, the product must generally be moved (transferred) from one location to another during the series of processing steps. At each processing location, accurate positioning of the product is generally required. In automated communications and information systems, the terms transfer and positioning refer to the movement of data (or electrical signals) among various processing units and the delivery of information to output terminals (printers, video display units, etc.) for interpretation and use by humans.

1basic building blocks of automation

2machine programming

3versatile

4to be readily generated

5the molding of plastic

6the shaping of metal

7automated manufacturing systems

8to entail

9to transform the entity from one state or condition into another

10the series of processing steps

11the processing of data in a computerized information system

12the delivery of information to output terminals

2. Make up 8 sentences with the words from the glossary. READING COMPREHENSION

1. Answer the questions.

1. What are the three basic building blocks of automation? 2. What is an automated system designed for?

3. Why is electric power the most versatile?

4. Where is electrical power generated from?

5. Can electrical power be readily converted into other types of power?

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6. What are the two types of the actions performed by automated systems? 7. What actions entail the use of energy to transform the entity from one

state or condition into another one?

8. What do the terms transfer and positioning refer to in automated communications and information systems?

2. Complete the sentences.

1. There are many sources of … available, but the most commonly used power in today’s automated systems is … .

2. Electrical power is the most …, because it can be readily generated from other sources, such as … fuel, hydroelectric, solar, and … .

3. In addition, electrical energy can be stored in …-…, long-life batteries. 4. The actions performed by automated systems are generally of two

types: … and transfer and … .

5. In the first case, energy is applied to accomplish some … … on some entity.

6. The process may involve the shaping of metal, the … of plastic, the switching of electrical signals in a … … , or the processing of data in a computerized … system.

7. All these actions … the use of energy to transform the entity from one state or … into another more valuable state or condition.

8. The second type of action—transfer and positioning—is most readily seen in … manufacturing systems designed to perform work on a product.

9. At each processing location, … positioning of the product is generally required.

10. In automated communications and information systems, the terms transfer and positioning refer to the … of data.

ANALYZE

1. Match the words with their English synonyms:

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2. Give the English equivalents:

1.автоматизированное производство

2.повлечь за собой

3.выходная клемма

4.литье пластмассы

5.ценный

WORD BUILDING

1. Read the words and say what suffixes they have and what parts of speech they belong to.

1.use, useful, usefulness;

2.invent, inventor, invention;

3.work, worker;

5.special, specialty, specialist;

6.practice, practical;

7.contain, container;

8.lecture, lecturer;

9.create, creative, creation;

10.accelerate, acceleration, accelerator;

11.determine, determination;

12.proper, properly, property;

13.science, scientific, scientist;

14.discover, discovery, discoverer;

15.important, importance;

16.arrange, arrangement;

17.capable, capability;

18.apply, application.

GRAMMAR

1. Translate the following sentences into Russian paying attention to the predicates in the Perfect Passive.

1. This theory has been used for analyzing the experimental data. 2. In my opinion this result has not been proved by anybody. 3. The apparatus used in our research has been described recently.

4. We must compare our data with those that have been obtained by other researchers.

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5. Many difficulties had been overcome before the researcher succeeded in his work.

6. After the new device had been tested it was installed in our laboratory. 7. The construction of this television centre will have been completed by

the end of the next year.

8. In our country great progress has been achieved in developing all branches of science and engineering.

9. Many different devices have been created in order to improve the performance of communications.

10. The information has been based on the data received from a computer. 11. Much research has been carried out in order to establish the causes of

this phenomenon.

12. This question has already been discussed at the conference.

13. By the end of the year a large variety of electronic devices will have been produced.

14. This equipment had been repaired before you came. 15. This text has just been translated.

TRANSLATE

1. Translate from English into Russian:

1. The most commonly used power in today’s automated systems is electricity.

2. The actions performed by automated systems are generally of two types: processing and transfer and positioning.

3. Energy is applied to accomplish some processing operation on some entity.

4. Transfer and positioning are most readily seen in automated manufacturing systems designed to perform work on a product.

5. The product must generally be moved (transferred) from one location to another during the series of processing steps.

2. Translate the text from English into Russian:

WHAT IS A PNEUMATIC SYSTEM?

In machine automation a pneumatic system provides a simple and costeffective means to move, clamp, rotate, grind and screw.

A pneumatic system is a collection of interconnected components using compressed air to do work for automated equipment. Examples can be found

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in industrial manufacturing, a home garage or a dentist office. This work is produced in the form of linear or rotary motion. The compressed air or pressurized gas is usually filtered and dried to protect the cylinders, actuators, tools and bladders performing the work. Some applications require a lubrication device that adds an oil mist to the closed pressurized system.

Pneumatics is an application of fluid power – in this case the use of a gaseous media under pressure to generate, transmit and control power; typically using compressed gas such as air at a pressure of 60 to 120 pounds per square inch (PSI). Hydraulics is another form of fluid power, which uses a liquid media such as oil but at a much higher pressure with a typical range of 800 to 5000 PSI.

A big reason pneumatics are used is due to simplicity. With little experience, on-off control of machines and equipment can be designed and assembled quickly using pneumatic components such as valves and cylinders. With proper air preparation, pneumatics systems are also reliable, providing a long service life with little maintenance needed.

While a design using pneumatics is simple, there are some techniques to help make a better, more efficient system. It’s important to eliminate leaks. Any signs of an air leak should be addressed immediately. Related to this is tube length. Shorter tube lengths minimize system volume that must be pressurized and wasted each cycle, in turn minimizing air use. A valve mounted directly to a cylinder is an extreme example, providing the quickest pneumatic system response as well.

When selecting pneumatic components, be sure to not oversize them. This includes cylinders, valves, hose and tubes. Use online pneumatic air consumption tools to assist with this. Basically, determine the force needed to perform the work, calculating cylinder bore size based on this and the pressure available. With the pressure and cylinder bore known, calculate the valve air volume in cubic feet per minute (CFM), using the pressure, bore, stroke length and time for stroke.

While the cylinder is performing work, during clamping for example, a suitable design pressure of 60 to 80 PSI is common. However, retracting the clamps at a lower pressure uses less energy, so consider using a low pressure return or homing pressure.

Pneumatic systems are common in industrial machine automation. Be sure to supply, prepare and distribute the air properly. When correctly selected, assembled and installed, pneumatic devices and actuators will have a long, efficient life with limited maintenance required.

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3. Make the glossary to the text above. Fill in the table.

1cost-effective

2linear or rotary motion

3closed pressurized system

4actuators

5compressed air

6bladder

7a lubrication device

8a gaseous media

9to eliminate leaks

10to generate, transmit and control power

11little maintenance needed

12hose

SPEAKING

1. Speak about the power source using the glossary.

2. Make the plan of the text "What is a Pneumatic System?" and reproduce it.

WRITING

1.Write the summary of the text "Power Source".

2.Write the summary of the text "What is a Pneumatic System?"

LESSON 5. FEEDBACK CONTROLS

PREVIEW

Answer the questions. Then talk about your answers.

1. Where are feedback controls used?

2. What is the purpose of the controller and actuating devices in the feedback system?

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VOCABULARY

READING

READ AND TRANSLATE THE TEXT FEEDBACK CONTROLS

Feedback controls are widely used in modern automated systems. A feedback control system consists of five basic components: (1) input, (2) process being controlled, (3) output, (4) sensing elements, and (5) controller and actuating devices. The term closed-loop feedback control is often used to describe this kind of system.

The input to the system is the reference value, or set point, for the system output. This represents the desired operating value of the output. Using the previous example of the heating system as an illustration, the input is the desired temperature setting for a room. The process being controlled is the heater (e.g., furnace). In other feedback systems, the process might be a manufacturing operation, the rocket engines on a space shuttle, the automobile engine in cruise control, or any of a variety of other processes to which power is applied. The output is the variable of the process that is being measured and compared to the input; in the above example, it is room temperature.

The sensing elements are the measuring devices used in the feedback loop to monitor the value of the output variable. In the heating system example, this function is normally accomplished using a bimetallic strip. This device consists of two metal strips joined along their lengths. The two metals possess different thermal expansion coefficients; thus, when the temperature of the strip is raised, it flexes in direct proportion to the temperature

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change. As such, the bimetallic strip is capable of measuring temperature. There are many different kinds of sensors used in feedback control systems for automation.

The purpose of the controller and actuating devices in the feedback system is to compare the measured output value with the reference input value and to reduce the difference between them. In general, the controller and actuator of the system are the mechanisms by which changes in the process are accomplished to influence the output variable. These mechanisms are usually designed specifically for the system and consist of devices such as motors, valves, solenoid switches, piston cylinders, gears, power screws, pulley systems, chain drives, and other mechanical and electrical components. The switch connected to the bimetallic strip of the thermostat is the controller and actuating device for the heating system. When the output (room temperature) is below the set point, the switch turns on the heater. When the temperature exceeds the set point, the heat is turned off.

DEVELOPING ACADEMIC VOCABULARY

1. Make the glossary to the text.

1a feedback control system

2closed-loop feedback control

3the reference value

4the desired operating value of the output

5the heating system

6a manufacturing operation

7a space shuttle

8cruise control

9sensing elements

10a bimetallic strip

11thermal expansion

12actuating devices

13controller

14solenoid switch

15piston cylinder

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16gear

17power screw

18pulley system

19chain drive

20to exceed

2. Make up 8 sentences with the words from the glossary.

READING COMPREHENSION 1. Answer the questions.

1.How many components does a feedback control system consist of?

2.What are the sensing elements?

3. What is the purpose of the controller and actuating devices in the feedback system?

4. How are the controller and actuator designed?

2. Complete the sentences.

1. The input to the system is the … value, or set point, for the system output.

2. The output is the … of the process that is being measured and compared to the input.

3. The … elements are the measuring devices used in the feedback … to monitor the value of the output variable.

4. The two metals possess different … expansion coefficients; thus, when the temperature of the strip is raised, it flexes in direct … to the temperature change.

5. There are many different kinds of sensors used in … control systems for automation.

6. The purpose of the controller and … devices in the feedback system is to compare the measured … value with the reference input value and to reduce the difference between them.

7. The controller and actuator of the system are the … by which changes in the process are accomplished to influence the output variable.

8. These mechanisms are usually designed specifically for the system and consist of devices such as motors, valves, … switches, piston cylinders, gears, power…, pulley systems, chain… , and other mechanical and electrical components.

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