chine keeps sending the 7) ___ to the machine and the operation continuous same as verified in the computer software.

CNC has touched almost every 8) ___ of manufacturing. Many machining processes have been improved and 9) ___ through the use of CNC. Let’s look at some of the specific fields and place the emphasis on the manufacturing processes 10) ___ by CNC machine usage.

Machining processes that have traditionally been done on 11) ___

112

* Find the sentences with the Formal Subject in the text below and translate them.

113

IV. What can you see in the pictures (pic. 30 – 32)? Have you seen such things with your own eyes? How do they work?

Си Pic.б30 Pic. 31

А Д И

Pic. 32

V. Read the text, then answer the questions in Ex. IV once again.

MATERIAL HANDLING SYSTEM (MHS)

Material Handling System (MHS) is used to move and store parts, as well as materials used in processing the parts (e.g., tools, coolant, wastes).

There are two principal forms of part transport: parts must be moved from outside the system into it, and they must be conveyed within the sys-

114

tem. Usually it is not convenient to combine these functions because movement into the system involves raw parts while movement within the system involves part, fixture and pallet assemblies.

An FMS is capable of simultaneously processing a wide variety of parts at different work stations. Parts are loaded and unloaded at a particu- Сlar location, and pallets are used to transport parts between machines. Once a part is loaded into the system, it is moved from the station to the other one under the computer control, its path being dependent on its pro-

cessing requirements, machine loads and other constraints of the system. Within the system, there are many possible pallet-movement designs.

Theиthree principal categories are carts, conveyors, and robots. Guidance and control of carts can take different forms. Carts can move along tracks, energized and controlled externally by the central computer. Sensors located at appropriate points along the track identify the precise location of the cart andбcan be used to position it to the required tolerance (typically 0.06 in) to transfer pallets to a machine or unload station. All carts should have dead-man bumpers at each end to help prevent accidents.

Battery-powered carts can be moved along a flat floor, guided by an antenna that detects aАwire embedded below the surface. Position sensors still must be used to control pallet transfer.

Another cart design may use a tow chain in a trough under the floor. The chain moves continuously, and cart movement is controlled by extending a drive pin from the cart downДinto the chain. At specific points along the guideway, computer-operated cam-type stop mechanisms raise the drive pins to cart movement. One advantage of this system is that it can provide some automatic buffering with stationary carts along the track. A variation of this method uses a floor mounted spinning cylinder that imparts motion to the roller drive of individual carts;Иa computer initiates drive disengagement, and the carts can be stopped at selectable locations.

Powered conveyors can be used for basic transportation between flexible machining cells or for positioning parts to interact with robots or other handling devices. Powered roller conveyors are designed to move pallets from the load stations to pallet exchangers located on the machines. Individual sections can have separate drives to control placement of pallets near machines. Special switches can provide feedback to locate pallets along the conveyor.

Asynchronous conveyors based on the principle of rotating tubes are used to place loads precisely for robots, as well as to move loads at high speeds. In machining centres, specialized conveyors us can be designed to

115

handle any type of part from operation to operation. Overhead power-and- free conveyors offer flexibility to a manufacturing operation.

Besides, self-powered monorails independently drive trolleys that can run on the level or uphill. A master controller directs the trolleys in highly flexible configurations.

СVarious types of cranes can be employed to manoeuvre parts too heavy to lift manually, and this technology includes robots as well.

It is of importance to note that automated storage and retrieval systems (AS/RS) add more than control and space saving to a manufacturing operation. As flexible manufacturing systems increase their output and the variety of parts that will be produced in small lots, AS/RS fit the needs for buffer storage. Some new FMSs are being designed with raw stock being stored in AS/RS and delivered to machines by automatic guided vehicles. The AS/RS can also provide quick access to the jigs, fixtures and tooling

116

VIII. Make up special questions (Active or Passive Voice) to the words in bold. Answer the questions of your partner.

IX. Complete the chart using the information from the text.

B. Role-play this dialogue with your partner. Remember to say Hello and Good-bye.

117

HOME TASK 16

A. Memorize the words from Ex. I and be ready to do a dictation.

B. Using this lesson, make a crossword puzzle (10 words). Then let your groupmates do it.

C. Make a PowerPoint presentation (10 slides) about carts, conveyors or robots used for handling materials. You need to find some more facts yourself in the Internet. Remember to discuss the assess-

tion of the cart and can be used to position it to the required tolerance to transfer pallets to a machine or unload station. All carts should have deadman bumpers at each 20) ___ to help prevent 21) ___.

Battery-powered carts can be moved along a 22) ___ floor, guided by an 23) ___ that detects a 24) ___ embedded below the surface. Position 25)

___ still must be used to control pallet transfer.

To sum it up, it is necessary to say that the user today is looking for automatic material 26) ___ system. He wants to be sure that a part can be

118

27) ___ when it is needed. Such system is automatic 28) ___ vehicles which is beginning to take a 29) ___ role in material handling. The 30) ___

vehicle usually carries the workpiece, on a machine pallet or fixture base, from work cell to work cell. One can say that AVG is not only a transporter of parts and tools, it is also a factory system for delivery, the mode

Сof transportation for the highly flexible systems.

How many mistakes have you done? What are they?

What were the most difficult tasks for you? Why?

Lessonи17

 Refresh the words in Ex. I (Lesson 16) and get ready to have a

dictation. Doбthe crosswords of your groupmates. Share your Power-

Point presentations and be ready to answer the questions of your groupmates.

I. Listen and repeat. Using the dictionary, write in the [trxn'skripSn] of the words into the table below.

119

II. Find the words in the text and translate the word combinations with these words.

III. Work in pairs. Refresh the information about the Numerals (study the prompts in italics). Think of 2 or 3 questions using the words from Ex. I. Let your partner answer the questions in writing.

5th line: 1 word that is a synonym of the title or is very similar to it. vehicle laser technology navigation sensor zone

120

V. There are various anchor charts that are helpful in memorizing important facts. Look at the pictures below and analyze them (pic. 33 - 36). Read the text and make your anchor chart.

121

AUTOMATED GUIDED VEHICLE (AGV)

AGV (Automated Guided Vehicle) is an automatically guided vehicle (battery operated) which moves on guided path like magnetic tape,

wire on floor or uses a vision or laser guidance, typically performing repetitive and predefined logistic tasks in industry or warehouses constantly 24h / 7days. Application of the automatic guided vehicles was broadened during the late 20th century and they are no longer restricted to industrial environments.

Сlinois.иThe inventor’s idea was to automate the standard “man-on-board” tow truck traditionally employed in factories and warehouses. The dream came true when the first AGV started running on wire guided system embedded in the factory floor in 1953. Today, the AGV plays an important role in the design of new factories and warehouses, safely moving goods to their rightful destinations.

The first AGV was invented by Berrett Electronics of Northbrook, Il-

costs by helpingбto automate a manufacturing facility or warehouse. The AGV can be used to tow objects behind them in trailers, which can autonomously attach and can be used to move raw materials or finished product. The AGV can also be used to store objects on a bed and can be placed on a

Automated guided vehicles (AGVs) increase efficiency and reduce

set of motorized rollersА(conveyor) and then pushed off by reversing them. These days AGVs are employed in almost every industry, including, pulp, paper, metals, newspaper, and general manufacturing.

An AGV can also be called a laser guided vehicle (LGV) due to its lased guidance method or self-guided vehicle (SGV). Lower cost versions of AGVs are often called Automated Guided Carts (AGCs) and are usually guided by magnetic tape. AGCs are available in a variety of models

Wire guided is a term used to describe vehicles that use a wire embedded in the floor to guide the vehicles. The wired sensor is placed on the bottom of the robot and is placed facing the ground. A slot is cut in the ground and a wire is placed approximately 1 inch below the ground. The sensor detects the radio frequency being transmitted from the wire and follows it.

122

Tape Guided

Many light duty AGVs (some known as automated guided carts or AGCs) use tape for the guide path. The tapes can be one of two styles: magnetic or colored. A specific guide sensor is used to follow the path of the tape. A tape guidance system is flexible in comparison with the wire

Сguided system and can be easily removed and relocated if the course needs changing. It also does not involve the expense of cutting the factory or

warehouse floor for the entire travel route. Additionally, it is considered a “passive” system since it does not require the guide medium to be energized as wire does. Colored tape is initially less expensive, but lacks the advantage of being embedded in high traffic areas where the tape may become damaged or dirty. A flexible magnetic bar can also be embedded in the floor like wire but works under the same provision as magnetic tape and so remains un-powered or passive.

и Laser бTarget Navigation

Over the years the technology has become more sophisticated and today automated vehicles are mainly Laser navigated, e.g. LGV (Laser Guided Vehicle). In an automated process, LGVs are programmed to communicate (via an offА-board server) with other robots to ensure product is moved smoothly through the warehouse, whether it is being stored for future use or sent directly to shipping areas. The wireless navigation is done by mounting retro reflective tape on walls, poles or machines. The AGV carries a laser transmitter and receiver on a rotating turret. The laser is sent off then received again the angle and (sometimes) distance is auto-

The use of modulated laser light gives greater range and accuracy over pulsed laser systems. By emitting a continuous fan of modulated laser light a system can obtain an uninterrupted reflection as soon as the scanner achieves line of sight with a reflector. The reflection ceases at the trailing edge of the reflector which ensures an accurate and consistent measurement from every reflector on every scan.

AGV Types

Towing/Tugger AGVs were the first type introduced and are still a very popular type today. Towing vehicles can pull a multitude of trailer types and have capacities ranging from 8,000 pounds to 60,000 pounds.

123

Unit Load AGVs are equipped with decks, which permit unit load transportation and often automatic load transfer. The decks can either be lift and lower type, powered or non-powered roller, chain or belt decks or

Pic. 37

124

IX. Present your anchor charts to your group and choose the one you like. Give your arguments.

HOME TASK 17

СA. Memorize the words from Ex. I and be ready to do a dictation.

B. Be ready to retell the text “Automated guided vehicle (AGV)”using the plan.

ние томат ческомбреж ме по заранее заданной программе или управ-

C. Translate from Russian into English. Choose the best translation.

AGV – автомат чески управляемые тележки, отличное решедля автомат зац производства или склада.

Это транспортер с электроприводом, предназначенный для пе-

ремещен я друг х манипуляций с грузами. Может работать в ав-

ляться вручную. В автоматическом режиме тележка не требует присутств я оператора, поэтому может использоваться на опасных или вредных производствах. Кроме этого, отсутствие оператора дает ряд преимуществ – оптимизацию затрат на персонал, исключение произ-

Тележка можетАоснащаться различными приспособлениями для работы с грузами – манипуляторами, захватами, роллерами. Мы предлагаем как стандартные решения, так и индивидуальные под

водственных оши ок вследствие человеческого фактора, улучшение условий труда благодаря снижению физических усилий операторов.

tasks in industry or warehouses constantly 24h / 7days.

Wire guided is a term used to describe 6) ___ that use a wire 7) ___

in the floor to guide the vehicles. The wired 8) ___ is placed on the bottom of the 9) ___ and is placed facing the 10) ___. A slot is 11) ___ in the ground and a wire is placed approximately 12) ___ inch below the ground. The sensor 13) ___ the radio frequency being transmitted from the wire and 14) ___ it.

125

Tape Guided

Many light duty AGVs use tape for the guide path. The tapes can be one of two styles: 15) ___ or 16) ___. A specific guide 17) ___ is used to follow the path of the tape. A tape guidance system is 18) ___ in comparison with the wire guided system and can be easily 19) ___ and relocated if the course needs changing. It also does not involve the expense of cutting the factory or warehouse 20) ___ for the entire travel route. Additionally, it is considered a “21) ___” system since it does not require the guide medium to be energized as wire does. 22) ___ tape is initially less 23) ___, but lacks the advantage of being embedded in high traffic areas where the tape

126