Faculty of Engineering University of Kragujevac

Electro-mechanical broaching machine

Profesor: Student: Sandra Stefanović Asad Masad

Abstract

Broaching is a process of metal cutting. It is about operation in one pass. The tool is broaches

and has several cutting edges. In next presentation will be explain type of tools, procedures of

treatment, methods of treatment and others. The machine used for this treatments is broaching

machine and the thesis provides a systematic model of vertical broaching machines.

Key words: Broaching, broaching tools, broaching machine

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Table of contents

1. Introduction................................................................................................................................................3

2. Proccessing of broaching...........................................................................................................................4

2.1 Types of threading...............................................................................................................................5

2.2 Cutting sheme......................................................................................................................................6

3. Machines and tools in processing of broaching.........................................................................................8

4. Modeling elements of electro-mechanical broaching machine...............................................................11

5. Conclusion...............................................................................................................................................14

6. Literature..................................................................................................................................................15

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1. Introduction

Broaching operation represents metal processing, where the processing is done in one pass. The

tool is broaches and designed to linearly passes perpendicular to the workpiece in the direction of

the axis of the tool. The relative movement of the tool through the workpiece provides broaching

machines (Broaching). The tool can be pushed (which is less common method of treatment), or

drawn through the workpiece. Broaching can be internal (when the tool handles the inner surface

of the workpiece) or external (when the tool processes the outer surface of the workpiece).

Technology-through processing is explained in the second chapter describes the kinematics-

through processing where we can see the position of the tool in the treatment of internal and

external broaching, broaching types, methods and types of broaching and cutting scheme.

The third chapter describes the machines for broaching of some manufacturers and their main

characteristics, the tools in the processing of broaching and their basic structural elements. Also

the choice of form space between teeth, chip breaker and handles broaches (for internal and

external broaching).

Based on the above characteristics and broaching broaches the fourth chapter was used for

modeling the electro-mechanical parts Broaching, or gear and rack, chuck tools, pole mount and

an electric motor, in the program CATIA V5R21. Before ten or more years with the Faculty of

Mechanical Engineering, professors decided to construct broaching machine, whose made almost

all the elements of the machine and it is not finished yet. Broaching is modeled according to the

already existing elements.

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2. Proccessing of broaching

The processing of broaching characterized by high productivity in terms of high series and mass

production and high productivity of machining processes. Despite the simple kinematics

processing this treatment process is one of the most complex processes of metal processing. The

reasons are in the fact that the processing of broaching usually finishing operation and that

processing is performed at very high values of loads of tools and machines. In this connection,

the entire machining system (tools, machines, compression fittings) should be characterized by

high levels of static and dynamic stability. Due to the high cost of tools, broaching applies only

in standard, high series and mass production (Nedić, 2007).

In most cases, processing is performed by passing the linear movement tools. The workpiece do

not perform support the movement, because support movement actually does not exist, except in

some special cases (helical broaches). Support motion in some way is incorporated in the tool

itself. Processing is carried out by drawing a tool, rarely repression, along the axis of the

workpiece. In Figure 2.1 are presented processing scheme for internal and external broaching

with numbered positions. In position 1 is broaches, position 2 guides, 3. work desk, 4. the

workpiece (Nedić, 2007).

Figure 2.1 Scheme of processing by broaching a) internal, b) external (Nedić, 2007)

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2.1 Types of threading

There are three types of threading:

Progressive broaching

Rotary broaching

Method of processing stamping

In progressive broaching, broaches have cutting edges, they have the same distance from each

other but they have different widths (http://www.ignou.ac.in/upload/broaching).

Figure 2.2 Scheme of progressive broaching

Rotary broaching is used to remove large amounts of material in the holes that are forged or cast

which is not desirable progressive broaching. The teeth in these broaches are arranged in extent

when turning the cuts filings off a piece and allow filings evacuation. This is recommended for the

production of square or hexagonal openings of round (http://www.ignou.ac.in/upload/broaching).

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Workpice

Internal broaches

Figure 2.3 Scheme of rotary broaching

A method of processing stamping is used for making polished and final surface on the metal

piece. This is used for finishing holes. The teeth of this tool are rounded and not cutting, or

compress and rub the surface of the metal (http://www.ignou.ac.in/upload/broaching).

Figure 2.4 Scheme of processing tools for stamping

2.2 Cutting sheme

Cutting scheme to broaching means cutting adopted the order (remove) bonus for the entire

treatment. There are a number of different cutting schemes, which mainly depends on the shape

and dimensions of the profile of the workpiece. It is very important that you make at least a

rough optimization of selection schemes cutting (Tadić, 2015).

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Workpiece Rotary broaches

Stamping broaches

This means integrally review and analyze selected scheme and cutting effects achieved in terms

of:

• the necessary traction force of machines

• load broaches (critical tensile stresses at broaches for internal broaching)

• required length broach or number broaches included

• the value of cutting depth per tooth (steps per tooth)

• the number of teeth broaches

• achieving the required geometric accuracy and high surface quality and others.

In Figure 2.5 shows some of the possible schemes of cutting.

Figure 2.5 Cutting scheme to broaching (Tadić, 2015)

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3. Machines and tools in processing of broaching

Vertical broaching for internal broaching (Figure 3.1) are the most common type of machine

constructions for internal broaching. The workpiece (7) is placed on a desk machine (2), and the

tool is in the initial stage of processing, before processing, placed in the back of a leading part of

the machine (1). The tool, leading through the last part leads into the operating position when the

front receiving portion (4) acceptance tool. Thanks to the operating system machine (electric

motor 5, the transmission system 6 and the mechanism for converting rotary to linear motion)

leading the front part of the machine receives the necessary movement and traction machines,

necessary for the realization of machining processes. Upon completion of the cutting process

(reaching lower points travel tools), the workpiece is removed from the work table and the tool

returns to the starting position (Tadić, 2015).

Figure 3.1 Scheme of pneumatic vertical Broaching for internal broaching (Tadić, 2015)

Horizontal broaching machine for internal broaching (Figure 3.2) are working on a similar

principle, except that the movement of the tool (2) in the horizontal direction and what is

necessary to ensure an appropriate system for receiving and clamping the workpiece (1).

Horizontal broaching machines provide the possibility of continuous operation stationary tool if

the workpiece placed on the rotary table or conveyor belt (Tadić, 2015).

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Figure 3.2 Scheme of horizontal broaching machine for internal broaching (Tadić, 2015)

Basic structural elements of broaches defined depending on its purpose. In broaches for internal

threading (cylindrical broaches figure 3.3) basic elements are as follows:

1. handle broaches

2. neck broaches

3. the transition cone

4. the front part of the leading

5. cutting part

6. calibrated part

7. the last leading part

8. the receiving part

Figure 3.3 The basic elements of cylindrical broaches (Tadić, 2015)

Handle broaches used for acceptance by the eternal system broaching machine. The front part of

the leading broaches for guidance tools through pre-treated appropriately opening or profile that

formed the previous broaches (when dealing with a set of broaches). On the cutting part of

broaching tools are formed cutting segments (teeth) that after cutting profile scheme or in the

appropriate sections (progressive scheme) cut a complete supplement for treatment of swiping.

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On the part of the calibrated tools are calibrated formed teeth. The length of this part of the tool

depends on the number of calibrated teeth and their steps. The last part of the leading tools used

for leading tools already formed by the profile. The receiving part of the tool is used for

accepting tools by the receiving mechanism of the machine. In Figure 3.4 shows some of the

possible constructive solutions of space between the teeth (Tadić, 2015).

Figure 3.4 Some of the possible constructive solutions between the teeth (Tadić, 2015)

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4. Modeling elements of electro-mechanical broaching machine

Main purpose of the broaching machine is obtaining the desired shape of the workpiece by

removing excess material, it must receive adequate energy to be converted into mechanical work.

At a new machine for this purpose almost exclusively used electricity, and the drive is realized

by electric motors, using electricity from the grid converted into mechanical (Zahar, 1997).

Figure 4.1 Three-phase asynchronous motor with short-circuited rotor

For further transfer of rotary motion electro-motors can be used gear group, group transfer belts,

transfer chain groups and others. Or a combination of the group gear and transfer belts, as it is

used in a given broaching. The theme of the work does not require a more detailed study of the

driveline group of gears at broaching, so it will not go further on the subject. Due to the high

power required equipment attached to the three belt (belt) from the powertrain to the movement

of the drive (gear - gear lath) machines, to prevent it’s rapid shooting. In Figure 4.2 shows the

transfer model . The width of the belt is 54 mm, a length of the strap around 1650 mm.

Figure 4.2 gear housing and belt drive

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The desired movement is linear for broaching. This can be achieved in several ways. For

example, a curve mechanism which is very good but it requires a large construction machine,

then the worm gear which is also very good, or using the gear pair (gear - gear lath) that does not

require a complex structure in Figure 4.3. Vertical broaching machine concerned the benefits of

gear and gear-lath. Gear has a diameter of 43mm and a width of 40 mm with a modulus of 2.6.

Gear- lath has a length of 752 mm, a width of 40 mm and a modulus of teeth is also 2.6. Working

stroke is about 700 mm.

Figure 4.3 Timing couple

On the gear-lath is attached to the head for accepting and broaching tools (broaches) Figure 4.4.

Figure 4.4 The board

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In the Figure 4.5 are shown reception head and slider.

Figure 4.5 Reception head and slider

In the Figure 4.6 are shown vertical electro-mechanical broaching machine.

Figure 4.6 Vertical electro-mechanical broaching machine

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5. Conclusion

Broaching is one of the machining operations, which is used as a tool broaches. The process of

cutting has the one-movement, rectilinear. This processing is called highly productive because

the production of tools are expensive. Broaching can be for the inner surface, as well as for the

outer surface of the workpiece. Depending on the types of broaching cutting is classified as a

progressive cut, rotary cut and embossing surface.

Broaching machines is primarily divided into horizontal and vertical, indoor and outdoor

products, and also on the type of propulsion, whether they are hydraulic, electrical, or other

broaching. They are characterized by large mass, high traction force, high precision machining

and long production runs. There are various types of metal processing machines by broaching.

They may be machines for broaching hard materials, machines in which the workpiece moves a

stationary tool, small size machines, machines for spiral-through processing, machines where the

workpiece is heated, machines for continuous processing where there is a strip for work pieces,

machine which can be carried out by treatment with two tools simultaneously (Dual ram) etc.

Broaching tool selected based on the required length of threading, the mechanical properties of

the workpiece and geometric accuracy and the required quality of processing. The structural

elements of tools includes front and rear receiving part, the cutting teeth and space between the

teeth. Bonfire filings were no less important. Material of broaches should be higher hardness

depending on the type of workpiece.

The fourth chapter describes what is the primary task machines, approximate geometry and

function of each element. In addition to the existing basic elements are modeled elements (pole

slider and guides) to facilitate the work tools for returning to the starting position, made some

minor modifications to the receiving head to be coaxially with the opening in the mounting

bracket. The board of the toothed pair and the pulley has also been modified, it is possible to

easily set the belt on the pulley..

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6. References

[1] http://www.ignou.ac.in/upload/broaching (accessed September 19th, 2015)

[2] Nedić. B. (2007), Obrada metala rezanjem, Mašinski fakultet Kragujevac

[3] Tadić. T. (2015), Alati za provlačenje, Fakultet inženjerskih nauka, Kragujevac

[4] Zahar. S. (1997) Mašine alatke, Jugoslovensko društvo za tribologiju, Kragujevac

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