i

DESIGN OF AN EXTERNAL ELEVATOR SYSTEM

FOR YEDITEPE ENGINEERING BUILDING

ME 482 DESIGN OF MECHANICAL SYSTEMS

Term Project Report

Fall 2015

Group Members

President: Tugay TANIK

Notebook Keeper: Berk KÖTEŞLİ

Budget Officer: Doğukan KULUNÇKIRAN

Member: ATIL YÜKSEL

Group 1

Department: Mechanical Engineering

Instructor: Asst. Prof. Namık CIBLAK

15.05.2015

ii

Abstract

Capacity of the existing elevators in the Yeditepe University Engineering Building is

not sufficient to satisfy the demand. Teachers, students and other personnel queue up on the

elevators. Therefore, they lose time unnecessarily.

In this report, to solve this problem, an external elevator system was design for

Yeditepe University Engineering Building. Then, necessary components of the elevator were

specified. During the project, all phases of the design were performed and they were shown

in this report.

iii

Table of Contents Title Page ................................................................................................... Error! Bookmark not defined.

Abstract ....................................................................................................................................................ii

Table of Content ........................................................................................ Error! Bookmark not defined.

1. Introduction ......................................................................................................................................... 1

2. About Engineering Team .................................................................................................................... 2

3. Statement of the Need ......................................................................................................................... 3

4. Definition of the Problem .................................................................................................................... 4

5. Design Objectives ................................................................................................................................ 5

6. Scope ................................................................................................................................................... 6

7. Project Time Table .............................................................................................................................. 7

8. Design Partition Tree ........................................................................................................................... 8

9. Market Analysis .................................................................................................................................. 9

9.1. Patents ......................................................................................................................................... 9

9.2. Web Pages ................................................................................................................................. 10

9.3. Scientific Papers ....................................................................................................................... 11

10. Survey & Observation ..................................................................................................................... 12

10.1. Survey ...................................................................................................................................... 12

10.2 Observation .............................................................................................................................. 16

11. Preliminary Design Alternatives ..................................................................................................... 17

12. Selected Design ............................................................................................................................... 19

13. Detailed Design ............................................................................................................................... 23

13.1 Elevator Types ......................................................................................................................... 23

13.2. Component Selection .............................................................................................................. 34

13.2.1 Gearless Elevator Machine .............................................................................................. 34

13.2.2 Rope Pulley and Suspension System ............................................................................... 36

13.2.3 Lift System ........................................................................................................................ 37

13.2.4 Brakes ................................................................................................................................ 40

13.2.5 Guide Rails and Rubber .................................................................................................. 41

14. Conclusion ....................................................................................................................................... 42

15. References ....................................................................................................................................... 43

1

1. Introduction

Elevator systems are widely used in our daily life. There are several types and

mechanism of the elevator system. In this project, an external elevator system will be

designed to be built on the façade of the Engineering Building of Yeditepe University. The

need is defined as internal elevator systems of the building cannot satisfy the users’ needs in

terms of comfortable usage intensity, fast transportation and elder & disabled people usage.

By using and designing an external elevator system for the Engineering building, a satisfying

solution for this need will be created. Problems, objectives and scopes have been considered

and defined. Also, observations and surveys on the users were done to understand the actual

need and extra modifications. After this statements, literature and market survey have been

completed to get a useful idea for this design. Thus, preliminary designs have been started.

After all several preliminary designs for each components of the external elevator systems,

designed selection have been completed by using priority ranking of design criteria such as

aesthetics, function and cost. Thus, selected design has been developed and mechanic system

selections and calculations have been done.

2

2. About Engineering Team

We had an agreement with each team member that our team will be a simulation of an

actual inter – disciplinary engineering team charged with finding solutions to the problems in

this design project. We agree that we are members of a company named ELEVATECH.

Generally this company designs elevator systems and our following project is designing an

external elevator system for Yeditepe Engineering Building.

As a project group we have a division in liabilities. We choose a president, a budget

officer and a notebook keeper in order to maintain the order throughout the design project.

We also agree that in order to create an effective and successful design, all group members’

works will be for improving whole project, not for improving a part of the project.

Our strategy will be sharing our investigations with other team members at that very

moment and sharing opinions on that research together. This cooperation will help us to be up

to date all the time and be more productive. Communication will be managed with e-mail and

group network system in smart phones.

As we have discussed the most critical aim in this project we found that it is finishing

the project within the scheduled time and weekly complete the works and reports without any

delay. We will document all decisions and progresses and archive them both soft and hard.

The Meeting dates will be announced before, so all group members will be attending

the meetings without an excuse. Finally, we will be prioritizing engineering ethics and laws

during the project time.

President: Tugay Tanık

Budget Officer: Doğukan Kulunçkıran

Notebook Keeper: Berk Köteşli

Member: Atıl Yüksel

3

3. Statement of the Need

Declaration of the definition of need for an external elevator for Yeditepe

University Engineering Building is given below;

The current elevators inside of the Engineering Building cannot satisfy the users’

needs in terms of comfortable usage intensity, fast transportation and mobility for

elder and disabled people.

In order to build an external elevator system to the exterior facade of the Yeditepe

University Engineering Building to share the intensity of usage of other elevators

inside of the building. Also, would a new external elevator system be designed faster

than the existing ones and become visually pleasing?

Would it be possible to construct this external elevator system in such a way that

mobility and ease of use for elderly and disabled people is provided?

4

4. Definition of the Problem

Declaration of the statement of problem for an external elevator for Yeditepe

University Engineering Building is given below;

According to needs of customers, an external elevator system will be built to the

exterior facade of the Yeditepe University Engineering Building by taking into

consideration the needs of users and customers.

This elevator system should be suitable for elderly and disabled people who spend

time into the Yeditepe University.

External elevator should be designed by considering the guidelines, space and

mobility standards and techniques for elderly and disabled people.

External elevator should be play an crucial role on sharing intensity of usage of the

other internal elevators which have already been built into the building

According to survey results which are about current elevators into the building, Load

capacity is set as maximum 6 people however its control system should be design for

working 3-6 people averagely to increase the efficiency of the system.

By using survey results, comfort and visual design of the external elevator should

satisfy the users.

5

5. Design Objectives

Declaration of the objectives for an external elevator for Yeditepe University

Engineering Building is given below;

Sizes and location of external elevator should be

designed and selected to share the intensity of

usage of the other internal elevators into the

building.

External elevator should have 3-6 people

capacity for usage according to survey results.

External elevator should be designed to access

desired floors of the building by taking

consideration of the amount of users and

architectural structure and land structure of the

Engineering Building of the Yeditepe University.

Safety and velocity of the elevator should be

preferred according to the technical standards.

Design of the external elevator should be formed

as elegant and satisfying in terms of visual and

technical aspects by considering budget.

External elevator should be designed by

considering the guidelines, space and mobility

standards and techniques for elderly and disabled

people.

Air conditioning should be designed efficiently by considering weather conditions of the

location of the Yeditepe University; because external elevator should not be affected directly

from the outer temperature such as sunlight which causes increasing temperature inside of the

elevator or snow and rain which causes decreases temperature and increases the humidity of

the air inside of the external elevator.

Modern Elevator Design

6

6. Scope

Declaration of the scope for an external elevator for Yeditepe University Engineering

Building is given below;

Sizes and location of the external elevator is limited because of the land and architectural

structure of the building. During the surveying process for the location of the elevator,

some unavailable facades of the building were detected. Thus, external elevator should be

designed to locate available facades of the building to reduce the cost of project by

preventing building an extra external structure for the elevator system.

In terms as of providing the visual and technical aspects, transparency concept should be

provided by selecting appropriate material for the system considering performance and

cost of the material in terms of strength, safety, heat transfer, budget, visual aspects etc.

Load capacity is directly related with the sizes. Thus, capacity will be affected location

and sizes of the external elevator. According to survey results, external elevator system

should be design for 3-6 people intervals. Thus, location and sizes should be selecting

according to this scope.

7

7. Project Time Table

In this part of the project, time table have been prepared to avoid from the delays on

the project. By using this time table, all steps have been followed by considering the time

intervals.

Figure 7.1: Project Time Table

8

8. Design Partition Tree

External elevator system has been investigated by using five main systems which are

sensing, control, electric & electronic, lifting and cabin systems. All components of the

elevator systems were gathered together into these main systems. Using this method gives us

a chance to get extra coordination between the equipment, components and systems. The

partition tree is shown below

Figure 8.1: Design Partition Tree

9

9. Market Analysis

Before beginning design process, a lot of literature researches were done about elevator

design. This researches include patents, scientific papers and company web pages. Some of

them are shown as follows:

9.1. Patents

Belt Drive Elevator US1011423 (Dec. 12 1911) Double-effect emergency brake

EP1783087A2 (09.05.2007)

In patent research, some patents were compiled from USPTO and Google Patents.

They are about belt drive elevator, fluid pressure elevator, elevator energy conservation

system, emergency brake system and hydraulic elevator without machine room.

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9.2. Web Pages

In the web pages, there are one elevator company from Turkey, two elevator

companies which are pacesetter from other nations. Also, there are two web pages about

regulations of elevators from ASME and UCTEA chamber of mechanical engineers.

http://www.mmo.org.tr/akm/

(Information about Elevator control center and elevator regulations in Turkey)

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http://www.baerasansor.com/

(A Turkish elevator company)

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http://www.otisworldwide.com/

(Otis Elevator Company is the world’s largest manufacturer and maintainer of people-

moving products, including elevators, escalators and moving walkways. Otis is a part of UTC

Building & Industrial Systems, a unit of United Technologies Corp., a leading provider to the

aerospace and building systems industries worldwide.)

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http://www.schindler.com/us/internet/en/mobility-solutions/products/elevators.html

(Schindler elevators efficiently move passengers in notable buildings across North America,

including hospitals, hotels, offices, residences, airports, arenas and sports facilities. All

Schindler elevators are designed to meet governing safety codes, and meet or exceed

minimum ASME A17.1 codes. They also comply with the Americans with Disabilities Act.)

---------------------------------------------------------------------------------

http://www.kone.com/en/solutions/innovation/

(KONE is the industry forerunner in technological innovations. KONE is committed to

offering high quality, innovative and energy efficient People Flow® solutions that make

travel within and between buildings as smooth as possible.)

---------------------------------------------------------------------------------

https://www.asme.org/about-asme/who-we-are/standards/safety-codes-for-elevators-

and-escalators

(ASME offers the public and private sectors a comprehensive portfolio of codes and standards

offerings, which govern elevators and escalators)

11

9.3. Scientific Papers

The articles which were chosen from sciencedirect from our library page contain

general information and history of the elevator, multi direction cable free elevators, energy

consumption of the elevators, the modelling and simulation and of the dynamic responses of

an elevator system, a technic of vibration analysis of the elevators and accessible elevator for

bus.

Multi direction cable free elevator system Accessible elevator for bus

Distribution of the magnetic field induced by the magnets

Finite Element Analysis (FEA) by means of the software FLUX.

12

10. Survey & Observation

10.1. Survey

A survey which contains 5 fundamental questions about elevators into the Engineering

Building has been completed. Results were examined on Microsoft Excel and Graphs were

drawn according to these results. Our Survey includes 5 basic questions which are given

below:

1- How often do you use elevators into the Engineering Building?

2- How long do you have to wait to use elevators?

3- Are you content with comfort of the elevators?

4- Are you content with the visual design of the elevators?

5- Do you want a new external elevator to build on the façade of the Engineering

Building? Do you believe that it is necessary?

These 5 questions were answered by using 5 different grading options:

Very Poor Poor Average Good Very Good

According these options, questions were answered. Results and graphs are shown below:

For first question which is:

‘How often do you use elevators into the Engineering Building?’

0

8

Answer

7 7

0

2

4

6

8

10

12

14

16

Çok Az Az Orta Fazla Çok Fazla

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According these options, questions were answered. Results and graphs are shown below:

For second question which is:

‘How much longer do you have to wait to use elevators?’

According these options, questions were answered. Results and graphs are shown below:

For third question which is:

‘Are you contented with comfort of the elevators?’

31

6

19

8

0

2

4

6

8

10

12

14

16

18

20

Çok Az Az Orta Fazla Çok Fazla

Question 2

Kisi

#o

f A

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Answer

2 3

23

9

00

5

10

15

20

25

Çok Az Az Orta Fazla Çok Fazla

Question 3

Kisi

#o

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nsw

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Answer

14

3

11

19

310

2

4

6

8

10

12

14

16

18

20

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Question 4

Kisi

Answer

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5 4 5

11 12

0

2

4

6

8

10

12

14

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Question 5

Kisi

Answer

#o

f A

nsw

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According these options, questions were answered. Results and graphs are shown below:

For fourth question which is:

‘Are you contented with the visual design of the elevators?’

According these options, questions were answered. Results and graphs are shown below:

For fifth question which is:

‘Do you want to be built a new external elevator to the façade of the Engineering Building?

Do you believe that it is necessary?’

’

15

According to these graphs, some inferences were done. First graph gave us an idea

about the intensity of usage of the elevators. Thus we decided maximum load capacity of our

design as 3-6 people.

Also, the most common complaint was waiting the elevators to use. Therefore, we

focused on increasing the velocity and timing performance of our design. Also, some extra

applications can be applied on system to improve usability during intense mobility such as

elevator can be worked between only top floor and ground level.

Thirdly, users are generally contented with the comfort of the elevator such as air

conditioning, lightening and inertial sense due to the acceleration rate of the elevator.

However, we want to develop our design in terms of comfort of the elevator.

4th graph shows that visual design of the elevator system must be improved. Therefore,

just like we said in our objectives, creating an elegant design by using our transparency motto

gives us a chance to provide the visual and technical aspects that we want to see.

Finally, user takes a bright view of an external elevator system to the façade of the

building to share the intensity of usage of other elevators and they support this idea.

16

10.2 Observation

Elevator was observed to reach some statistical data between 10:45 - 11:00 AM and 12:00 -

12:16 PM.

Elevator was used by 30 people between 12:00 - 12:16 PM.

Elevator was used by 1.8 people per minute.

Average cycle time of elevator was detected as 2 minutes.

The number of free movement was observed as 3 times.

Average waiting time of people on the ground floor was detected as 1 minute.

Elevator moved from ground floor with 1.5 people as average.

Person or people who do not get on the elevator from ground floor, was not observed.

Overcrowding for elevator could not be observed between 12:00 - 12:16 PM.

Elevator was observed to reach some statistical data between 10:45 - 11:00 AM and 12:00 -

12:16 PM.

Elevator was used by 39 people between 10:45 - 11:00 AM.

Elevator was used by 2.6 people per minute.

Average cycle time of elevator was detected as 2.2 minutes.

The number of free movement was not observed.

Average waiting time of people on the ground floor was detected as 2.2 minute.

Elevator moved from ground floor with 4.4 people as average.

Person or people, who do not get on the elevator from ground floor, were not

observed.

Overcrowding for elevator could not be observed between 10:45 - 11:00 AM.

17

11. Preliminary Design Alternatives

When the preliminary design alternatives were produced, a priority ranking has been

voted to define our design criteria and motto. The ranking is shown below.

Table 11.1: Priority Ranking Table

After the selection of the priorty , several alternative design and drawings have been created for each

component of the elevator system such as buttons, control panel, cabin, mechanism, brake system

etc.At the beginnig of the project, transperancy is defined as our design motto.Several design

alternatives produced by considering objectives,scopes and need.The preliminary design examples are

shown below.

Elevator

Criteria Member 1 Member 2 Member 3 Member 4 SUM

~Relative

Weight (%)

Aesthetics 3 3 3 3 12 50

Function 2 1 2 2 7 29

Cost 1 2 1 1 5 21

Transparent Design Emergency Brake System

18

In this preliminary design alternatives,

for each components have been considered.

Mechanism has been designed. Also, an self-

cleaning device have been design for the

elevator system because of the fact that the

transparency was the most critical design

criteria for our external elevator system and

system has to be made of transparent material

such as tempered glass etc. After all these

alternative designs, the final design is selected

and developed.

Self-Cleaning Device Regulatable Counterweight

Slider Mechanism

19

12. Selected Design

During the design process of the external elevator, the architecture of the Engineering

Building was taken into consideration to be suitable for architecture of the building. Also,

design of the external elevator should enrich the architectural view of the Engineering

Building. Therefore, Seljuk (Selçuklu) architecture which is used on all buildings of the

university was selected as design criteria of the external elevator system. Low roof design

with red tiles, wood L-shaped puncheons, embossment and engraving, archway and double-

headed eagle, which is a symbol of the Seljuk culture, will be applied on this design of the

elevator. Likewise, a spacious and modern atmosphere will be formed by using together water

resistant woods for floor and ceiling of elevator cabin and mirrors for the walls for the

elevator cabin.

Machine room of the elevator system is placed the top of the system. Machine room

ventilation is provided by air duct which located side of it. At the bottom part of the system,

outside door and safety cab which are made of tempered glass disallow person entry under the

elevator. Also, outside door is only used for ground floor/basement entrance. Inside door

which located in side of the cabin is only used and activated for floors which are called as

mezzanine floors.

Front of the main entrance door was selected as location of the external elevator

because of the fact that the most commonly used entrance of the building by people is main

entrance door. This location provides to service 6 floors of the building externally. Also, at

this location, design of the external elevator overlaps with the architecture of the building.

Figure 12.1: GENERAL CONCEPT

20

Figure 12.2: CABIN DESIGN

21

During the design of control panel and buttons of the external elevator, visuality and

multi-functionality were taken into consideration. Buttons and Screen has been designed

canorously with the architecture and design of the building and external elevator system.

Number of buttons was determined by considering number of floors and other functions such

as air ventilation, alarm, communication system and multifunctional door buttons.

Buttons were designed for also considering

elder and disabled people. Therefore, braille which

is a type of alphabet for blind people was added to

the design of the buttons. Also, interactive voice

system which announces the floors and other

actions to the disabled people is added to the

system. Thus, external elevator system became

much more suitable for disable people. Screen of

the control panel was design to observe actions.

All functions can be controlled by observing the

screen. Also two speakers were located in both

side of the screen panel. Thus, actions and floors

can be announced.

Radio broadcast was added to the system to

increase the motivation and comfort of the users.

Other feature of the control panel is air ventilation

system. For cold or hot seasons, air ventilation

system provides the optimum temperature for the

external elevator cabin and users.

Automation system of the external elevator system

was designed carefully. User comment will be

read and automation system was programmed to

make a decision for direction of the movement of

the cabin.

Figure 12.3: CONTRTOL PANEL

22

Figure 12.4: LED SCREEN PANEL

Figure 12.5: BUTTON DESIGN

23

13. Detailed Design

13.1 Elevator Types

Elevators are categorized according to hoist mechanism to 4 main types:

1. Hydraulic Elevators

2. Pneumatic Elevators

3. Climbing elevator

4. Traction Elevators

1- Hydraulic Elevators

In hydraulic elevators, there is a piston at the bottom of the elevator that pushes the elevator

up. Hydraulic elevators are used for low-rise applications. The machine room for hydraulic

elevators is located at the ground of the elevator shaft.

Hydraulic Elevators

24

Hydraulic elevators are divided to two main types:

A- Holed Hydraulic Elevators

Holed hydraulic elevators have a sheave that extends below the floor of the elevator pit. This

sheave accepts the retracting piston as the elevator descends.

Holed (Conventional) Hydraulic Elevators

25

B- Hole-less Hydraulic Elevators

Hole-less hydraulic elevators have a piston on two side of the cab. There are 3 type of the

hole-less elevators:

a- Telescopic Hydraulic Elevators:

Telescopic hydraulic elevators have the telescoping pistons which are fixed at the base of the

pit. The telescopic elevators do not require a sheave or hole below the pit and they have 2 or 3

pieces of telescopic pistons.

Telescopic Hydraulic Elevators

26

b- Non-telescopic (single stage) Hydraulic Elevators:

Non-telescopic elevators have one piston on the each side of the cab.

Non-telescoping (single stage) Hydraulic Elevators

27

c- Roped Hydraulic Elevators

Roped hydraulic elevators use a combination of ropes and a piston to move the elevator.

Roped Hydraulic Elevators

.

28

2- Pneumatic Elevators

Pneumatic elevators are raised and lowered by controlling air pressure in a chamber in which

the elevator sits.

Pneumatic Elevators

29

3- Climbing elevator

Climbing elevator is a self-ascending elevator with its own propulsion. Mostly electric or

combustion engine are used for propulsion. Climbing elevators are often used in work and

construction areas.

Climbing elevator

30

4- Traction Elevators (Pull Elevators)

Traction elevators are lifted by ropes which pass over a wheel attached to an electric motor

above the elevator shaft. They are used for mid and high-rise applications and have much

higher travel speeds than hydraulic elevators. A counter weight makes the elevators more

efficient.

Traction Elevators (Pull Elevators)

31

Traction elevators have 3 main types as follows:

A- Geared Traction Elevators:

Geared traction elevators have a gearbox that is attached to the motor which drives the wheel

that moves the ropes.

Geared Traction Elevators

32

B- Gear-less Traction Elevators:

Gear-less traction elevators have the wheel attached directly to the motor.

Gear-less Traction Elevators

33

C- Machine Room-Less Elevators:

Machine room-less elevators are typically traction elevators that do not have a machine room

above the elevator shaft. The machine sits on the elevator shaft.

Machine Room-Less Elevators

In this project, machine room-less elevator type was selected and all components of

the elevator were chosen to be appropriate for it.

34

13.2. Component Selection

13.2.1 Gearless Elevator Machine

Parts of the gearless elevator machine:

ZETATOP SM160 was selected as gearless elevator machine.

ZETATOP SM160

Components of a gearless elevator machine (www.ziehl-abegg.com)

35

Technical specifications of the motor were given below tables. Highlighted options

were selected.

36

13.2.2 Rope Pulley and Suspension System

Elevator Rope Pulley (www.ziehl-abegg.com)

Elevator Suspension (http://www.contitech.de) 2:1 Elevator suspension system

(www.ziehl-abegg.com)

For reducing the weight of the

counterweight and increasing the

torque 2:1 (Half-wrap) suspension was

selected.

37

13.2.3 Lift System

Lifting system plays a very important role in this course project which was designed

external elevator system for Yeditepe University. There are 2 types of hoist mechanisms.

These are traction and hydraulic elevator.

Traction elevator is divided into two parts as geared and gearless. Geared traction

machines are driven by AC or DC electric motors and it uses worm gears to control

mechanical movement of elevator cabin. The electric motor in this design drives a worm-and-

gear-type reduction unit, which turns the hoisting sheave which is connected to a gearbox,

driven by a high-speed motor. These machines are generally used for up to 3 m/s speeds.

Gearless traction machines have low-RPM and high-torque electric motors which are

energized by AC or DC. It has five to eight lengths of wire cable which is known as wire

ropes, are connected to the top of the elevator and revolves the drive sheave in grooves.

Gearless traction elevators reach speeds of up to 10 m/s or even higher.

Geared Traction Machine Gearless Traction Machine

38

The hydraulic elevator has dominated the low-rise market because it is cheaper to

build, install and service, and because it has a decidedly better safety record than the electric

elevator. Especially in earthquake endangered areas, the hydraulic elevator has proven itself

to be clearly the safer option.

Hydraulic Elevator System

Some studies in residential elevator lifting technology helped improvement of basic

mechanical parts and safety features. In this design project, gearless traction machine was

used because of many advantages and PU (Polyurethane) coated belt system was used instead

of steel rope system result of group voting.

39

The innovation provided by using of polyrope instead of steel rope, is a revolution on

the elevator technology. This innovation causes fundamental changes on elevator

performance. PU coated belt system is better driving ability than steel rope system. It has

larger load capacity, small motor sizes and machine roomless system. It provides high

efficient due to lower power consumption. It requires less power inverter. It provides better

corrosion resistance due to PU coating. Besides it reduces noise by preventing the friction

between steel ropes and presents us system course comfortably.

PU Coated Steel Rope

40

13.2.4 Brakes

The most common elevator brake is made up of brake shoes with linings, a solenoid

assembly and a compressive spring assembly. This brake must be capable of stopping the

machine when the elevator cabin with 125 % of rated load is travelling at its rated speed and

must hold the system at rest afterwards. Zinc bonded asbestos-material which has a high

coefficient of friction, is used to improve the stopping ability in the breaks and if this material

has too high a coefficient of friction, jerky motion can be occurred in the elevator cabin.

There are 3 types of brakes which are used in the elevator systems. These are drum,

disc and band brakes but band brakes are not preferred. In this design project, drum brakes

was chosen result of voting because of many advantages. A drum brake system contains an

electromagnetic brake, consisting of a spring assembly, two brake shoes with linings and a

magnet assembly. Disc brakes have smaller and lighter hydraulic cylinders. Their wheel

calipers are somewhat simpler to recondition compared to calipers. It has built-in self-

energizing effect requires less input force such as hydraulic pressure. Drum brakes are less

expensive to produce and it has slightly lower frequency of maintenance due to better

corrosion resistance compared to disc brake system.

Drum Brake Components

41

13.2.5 Guide Rails and Rubber

Roller guides in the elevator system travel along rails in the hoist way so the elevator cabin

can moves properly without any damage. They provides comfortably elevator travel by

proven to reduce lateral vibration by as much as 50 %.

Neoprene rubber roller wheels are optimized for maximum ride comfort and minimal noise.

Neoprene compound provides the damping characteristics essential to ride quality in

passenger applications. Besides, roller guides are easy-to-install package and. They have ease

of interference and fully adjustable stabilizing springs

Roller Guide Guide Rail

42

14. Conclusion

In this project, an external elevator system for engineering building of Yeditepe

University has been designed by following all phases of design. Statement of need is

understood. Problem, scope, objectives were defined. A detailed literature survey and

observation have been completed. By using these results, alternative drawings and designs

were created. Most suitable design for each component is selected by voting method in our

team. Selected design was improved and calculations have been completed .All components

and equipment was selected by using these calculations. Thus, an efficient, visually pleasing,

economical and suitable design for elder and disabled people was created by using design

phases. Consequently, this project gives us a chance to improve our engineering skill and

procedure significance.

43

15. References

http://en.wikipedia.org/wiki/Elevator#Climbing_elevator

http://en.wikipedia.org/wiki/Elevator

http://www.archtoolbox.com/materials-systems/vertical-circulation/elevatortypes.html

http://www.electrical-knowhow.com/2012/04/elevators-types-and-classification-part.html

http://www.ziehl-abegg.com/ww/misc-205-Drive-Technology-for-elevators.html