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Файл:Английский язык для инженеров мехатроники. English for mechatronics engineers. Учебное пособие
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Design of machine elements fundamentals
Machine Design is the art of planning or devising new or improved machines to accomplish human need directly or indirectly.
Machine Design is a study of the decision-making process implemented
by the engineers, for the satisfaction of human need. It is concerned with the
process of building bridge between the limited resources available on one side
and the unlimited desires of the mankind on the other side.
In designing a machine component, it is necessary to have a good
knowledge of many subjects such as Mathematics, Engineering Mechanics,
Workshop Process and Engineering Drawing by which a designer can give
the optimum design.
CLASSIFICATION OF MACHINE DESIGN:
The machine design may be classified as follows:
1. Adoptive Design: – In this case the designer study about the existing
design and slightly modify the structure by imposing his ideas and design a
new machine which is similar to previous one. Example: – Bicycle, Car,
Watch, Television, computer etc.
2. Development Design: – In this design the designer should have indepth knowledge on material properties and basic design equations or basic
technical knowledge so that a developed new machine will be produced. Example: principles on bicycle, the developed design is motor cycle. Personnel
computer to Laptop.
3. New Design: – By using a basic scientific principle create something
new, which never existed before. This type of design needs a lot of research,
technical ability and creative thinking.
The following factors should be considered during the design of a ma-
chine component. They are as follows:
1. Type of load and stresses caused by the load: – The load, on a machine component, may act in several ways due to which the internal stresses
are generate, those are responsible for failure of component.
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2. Motion of the parts or kinematics of the machine: – The successful
operation of any machine depends upon the simplest arrangement of the parts,
which will give the motion required and this above said point should be taken
care during designing.
3. Selection of material: – It is very essential that a designer should have
a thorough knowledge of the properties of the materials and their behavior
under different working condition, without which it is very difficult to assign
particular material for a specific field of application.
4. Form and size of the parts: – During assigning form and size of any
machine part, it is necessary to know the forces which the part must sustain.
5. Use of standard parts: – The use of standard parts reduces the economics involved in the design component. To accommodate easy identification of material, replacements of worn-out parts and for easy manufacturing
the parameters of machine component are standardize. (Standardization
means dimension and shape of most widely used component such as bolts,
nuts, washer, screws, rivets, chains, belts, bearings, shaft etc. should be uniform for all manufacturing companies).
6. Safety of operation: – It is necessary that a designer should always
provide safety devices for the safety of the operator. It is the major requirement of a perfect a designed object.
7. Workshop Facilities: A design engineer should be familiar with the
limitations of his employer’s workshop, in order to avoid the necessity of
having work done in some other workshop.
8. Quantities of machine to be manufactured: – The number of machines to be manufactured affects the design in a number of ways, as it directly affects the economic involved in the process of manufacturing and it
also deals with the case of profit of the farm.
9. Cost of construction: – The aim of design engineer under all conditions should be to reduce the manufacturing cost to the minimum. It is the
important consideration involved in all kinds of design.
10. Assembling: – Every machine or structure must be assembled as a
unit before it can function. So, for easy assembling the design engineer must
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anticipate the exact location and the local facilities for erection. Means servicing can be done easily at any moment.
Machine Design, is highly iterative and an innovative process, which can
be defined as the application of technical information, scientific principles
together with innovative ideas and imagination to describe a mechanical system or a machine to perform precise functions with maximum efficiency and
economy.
DEVELOPING PROFESSIONAL VOCABULARY
Working out the meaning of unknown words
2. The following words in the box are all from the text above. Find
them in the text.
apply device rotating innovative capacity
3. For each word, read the sentence it occurs in and answer the ques-
tions.
d) Is the word positive, negative or neutral?
e) Is it a noun, adjective, adverb or verb?
f) Can you think of a word with a similar meaning (synonym) and one
with an opposite meaning (antonym)?
AFTER READING TASKS
4. Answer the following questions.
1. What is a machine?
2. What are machine elements? Could you give the definition?
2. How many groups can machine elements be classified into? What are
they?
3. What types of machine elements are included into the general-purpose
machine elements?
4. What types of machine elements are included into the special-purpose
machine elements?
5. What is the broad objective of designing a machine element?
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6. What is a classification of the machine design?
7. Can you describe each of the classified item of the machine design?
8. How many factors should be considered during a design of a machine
component? Name each factor.
9. What is a machine design?
5. Mark the statements as true (T) or false (F). Correct the false ones.
1. Machine elements can be classified into three groups:
– General purpose machine element
– Special purpose machine element
– Alternative purpose machine element
2. General purpose machine elements include: shafts, couplings, clutches,
bearings, springs, gears, and machine frames.
3. Couplings are usually designed for the unique application. Couplings
are long, cylindrical components used for transfer of torque and mechanical
power between two components.
4. The machine design can be classified into: development design and
new design.
5. There are ten factors, which can be considered during a design of machine components.
6. Match the words with their definitions/explanations.
a machine
1
clutches
2
a piston
3
a valve
4
is a cylindrical engine component that slides back
a
and forth in the cylinder bore by forces produced
during the combustion process. The piston acts as
a movable end of the combustion chamber.
is a device or natural object that regulates, directs
b
or controls the flow of a fluid (gases, liquids,
fluidized solids, or slurries) by opening, closing,
or partially obstructing various passageways.
is a study of the decision- making process imple-
c
mented by the engineers, for the satisfaction of human need.
it is necessary that a designer should always pro-
d
vide safety devices for the safety of the operator.
It is the major requirement of a perfect a designed
object.
74
adoptive design
5
machine design
6
safety of operation
7
8 cost of construction
the aim of design engineer under all conditions
e
should be to reduce the manufacturing cost to the
minimum. It is the important consideration involved in all kinds of design.
are mechanical device that allows the out-
f
put shaft to be disconnected from the rotating input
shaft. The clutch's input shaft is typically attached
to a motor, while the clutch's output shaft is connected to the mechanism that does the work.
in this case the designer study about the existing
g
design and slightly modify the structure by
imposing his ideas and design a new machine
which is similar to previous one. example: – bicycle, car, watch, television, computer etc.
is an assembly of elements, with successfully con-
h
strained relative motion, which is used for converting other forms of energy into mechanical energy
and does some particular kind of work.
7. Fill in the gaps in the following sentences.
1. A Machine is an a… of elements, with successfully c… r… m…, which
is used for c… other forms of e… into mechanical energy and d… some particular rind of w….
2. Machine Elements are f… components of machinery which p… specific t… and are designed to fit t… to form c… machines.
3. Gears are e… machine e… with toothed w… to transfer p… and rotation between two s….
4. Machine Design is the a… of planning or devising new or i… machines
to a… human n… directly or i….
5. This type of d…e needs a lot of r…, technical a… and c… thinking.
6. It is very e… that a d… should have a t… knowledge of the p… of the
materials and their b… under different w… condition, without which it is
very d… to assign particular m… for a s… field of application.
7. The number of machines to be m… affects the design in a n… of ways,
as it d… affect the e… involved in the process of m… and it also deals with
the c… of profit of the f….
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8. Machine Design, is highly i… and an i… process, which can be d… as
the application of t… information, scientific p… together with innovative i…
and imagination to d… a mechanical s… or a machine to p… precise f… with
maximum e… and economy.
8. Find synonyms.
element
1
device
2
purpose
3
conservation
4
design
5
innovative
6
fundamentals
7
aim
a
basics
b
construction
c
advanced
d
preservation
e
component
f
machine
g
WORD BUILDING
9. Form nouns adding the suffixes -er, -or to the given verbs. Translate the nouns and verbs into Russian
Example:
to design – a designer (конструировать – конструктор)
to describe – a describer (описывать – выражение, знаток)
1. to transmit
2. to eliminate
3. to prevent
4. to use
5. to regulate
6. to manufacture
7. to preserve
8. to reduce
9. to perform
10. Make sentences by putting the words in the correct order.
1. Shafts/ used/ power /mechanical /are /power /two /between /cylindrical
/components /for / components / transfer / and / long.
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2. Pistons /made / a / cast /alloy / for / are / for / excellent / and / lightweight / conductivity/ commonly / thermal / made /.
3. Acts /as /the / chamber /combustion / of / the / a / movable/ piston/ end.
4. It is the important consideration involved in all kinds of design. Is /the
/involved /in / kinds / all /important /of / design /consideration /it /.
5. Means servicing can be done easily at any moment. Easily / means /
servicing / at /any /moment /can / done / be /.
GRAMMAR FOCUS
Degrees of Comparison of Adjectives
In grammar, the degrees of comparison relate to adjectives. Every adjec-
tive can be written in one of three degrees:
The Positive Degree. This offers no comparison. It just tells us about
the existence of a quality. For example:
slow, beautiful, happy
The Comparative Degree. This compares two things to show which has
the lesser or greater degree of the quality. For example:
slower, more beautiful, happier
The Superlative Degree. This compares more than two things to show
which has the least or greatest degree of the quality. For example:
slowest, most beautiful, happiest
The comparative degree and the superlative degree are formed by adding
the suffixes ER and EST to the positive form of the adjective or by using
MORE and MOST before the positive form of the adjective. The choice of
ER, EST or MORE, MOST depends mostly on the number of syllables in the
adjective.
Positive degree: bright; important.
Comparative degree: brighter;
more important.
Superlative degree: brightest; most
important.
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10. Study the rule above. Make up Comparative and Superlative De-
grees of the following adjectives given in the Table below.
Positive Comparative Superlative
1. successful
2. relative
3. important
4. unique
5.mechanical
6.smooth
7. natural
8.essential
9.easy
10. major
11. iterative
12. innovative
13. wide
14. new
11. Compare two friends: Sam and Mark.
Example: Sam is 30. Mark is 32. Sam is younger than Mark.
1. Sam is almost two meters tall. Mark is 1 meter 79 tall. Mark …………
2. Sam has three children. Mark has two children. Mark …………………
3. Sam has a four-room flat. Mark has a three-room flat. Sam ……………
4. Sam earns $2000 a month. Mark earns $1500 a month. Mark …………
5. Sam is very handsome. Mark is not very handsome. Sam ……………
6. Sam speaks three foreign languages. Mark speaks two foreign lan-
guages. Sam ……………
7. Sam is very practical. Mark is not very practical. Mark ………………
8. Sam is a very good driver. Mark is not a very good driver. Sam ………
9. Sam is not very experienced. Mark is very experienced. Mark ………
12. Answer the following questions
Example: Which is cleverer: the monkey, the cow, or the kangaroo?
The kangaroo is cleverer than the cow but the monkey is the cleverest.
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1. Which is faster: the coach, the train, or the picture? ……………………
2. Which is bigger: Canada, the USA, or Russia? ………………………
3. Which is more difficult: German, Spanish, or Vietnamise?
4. Which is sweeter: strawberries, oranges, or mandarins?
5. Which is more frightening: thrillers, detective stories, or biography?
TRANSLATE
11. Read the text and translate it into Russian. Fill in the glossary.
word translation
practical application
design engineering
play an indispensable role
connect various parts
home appliances
gears transmit force
fasteners connect steel beams
to lay the foundation
to reflect creativity and innovation
to rotate the drum
to grab items by pneumatic grippers
innovative and unconventional uses
of machine elements
Practical Applications of Machine Elements in Design Engineering
In design engineering, machine elements are the building blocks that
power both modern technology and everyday utilities. Here, we look at some
significant areas where these elements play an indispensable role.
Transportation – Vehicles: Every vehicle, whether it's a car, a bicycle,
a ship or a plane, is made up of countless machine elements working seamlessly together. The engine of a car is an array of machine elements – gears
transmit force, pistons convert heat into mechanical energy, belts connect the
various moving parts, bearings aid in unrestricted motion, and fasteners keep
everything together.
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Manufacturing – Machinery: Manufacturing machines consist of assembly lines, conveyor systems, and robotic arms to name a few, which are
packed with various machine elements. Here, gears control motion and transmit force, belts and pulleys connect different sections, chains prevent slipping, while fasteners help assemble the machinery. A robotic arm illustrates
the concert: detect objects via sensors, move through servo motors, and grab
items by pneumatic grippers.
Construction – Civil Engineering: Machine elements are extensively
used in the construction industry. Hydraulic cylinders exert great force to lift
heavy materials, gears in cranes manage motion and force, fasteners connect
steel beams, while bearings ensure smooth operation of moving parts. Think
of an excavator digging, enabled by hydraulic cylinders and connected via
fasteners - machine elements in action.
Home Appliances: Everyday devices like washing machines, refrigerators, air conditioners, utilise machine elements. A washing machine incorporates machine elements like a drum (to hold clothes), a drive mechanism
(to rotate the drum), a water pump (to fill and empty the drum), and a control
system (to regulate all these elements).
In a nutshell, these applications illustrate how machine elements bring
machines – and by extension, our world - to life. From complex industrial
machinery to everyday home appliances, machine elements lay the foundation for innovation and utility across various industries.
Medical Devices – Prosthetics: In recent years, there has been a massive
advancement in prosthetic limbs, which heavily rely on machine elements.
The delivered motion, enabled via small motors and gears, allows the prosthetic to mimic human joints' movements. These elements are assembled into
a lightweight, durable plastic known as thermoplastics with screws and fasteners.
Space Exploration – Rovers: Space exploration rovers utilise machine
elements in innovative ways. For instance, the Mars Curiosity Rover has a
robotic arm (with elbow and wrist 'joints' mimicked by bearings), a drill (fastened to extract rock samples), and a ChemCam (to identify the chemical
composition of rocks from a distance), all running on a nuclear-powered
'heart'.
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