Design of an Automatic Machine for Stripping and Bending Insulated
Electrical Wire
by
Yevgeny Rapoport
An Engineering Project Submitted to the Graduate
Faculty of Rensselaer Polytechnic Institute
in Partial Fulfillment of the
Requirements for the degree of
MASTER OF ENGINEERING IN MECHANICAL ENGINEERING
Approved:
______________________________________________________
Professor Ernesto Gutierrez-Miravete, Engineering Project Adviser
_____________________________________
Professor Larry Ruff, Subject Matter Adviser
Rensselaer Polytechnic Institute
Hartford, CT
December, 2012
i
© Copyright 2012
by
Yevgeny Rapoport
All Rights Reserved
ii
CONTENTS
LIST OF TABLES ............................................................................................................. v
LIST OF FIGURES .......................................................................................................... vi
NOMENCLATUE ........................................................................................................... vii
ACRONYMS .................................................................................................................. viii
KEY WORDS ................................................................................................................... ix
ACKNOWLEDGMENT ................................................................................................... x
ABSTRACT ..................................................................................................................... xi
1. Introduction.................................................................................................................. 1
1.1
1.2
Background ........................................................................................................ 1
1.1.1
Automation............................................................................................. 1
1.1.2
Machine Function................................................................................... 1
Problem Description........................................................................................... 2
1.2.1
Requirements and Specifications ........................................................... 2
2. Full Machine ................................................................................................................ 3
2.1
Machine Description .......................................................................................... 3
2.2
Control System ................................................................................................... 6
3. Machine Design ........................................................................................................... 8
3.1
3.2
3.3
Subsystem #1: Free-Length Uncoiling .............................................................. 8
3.1.1
System Description ................................................................................ 8
3.1.2
Analytical Support ............................................................................... 10
Subsystem #2: Primary Feed ............................................................................ 14
3.2.1
System Description .............................................................................. 14
3.2.2
Analytical Support ............................................................................... 16
Subsystem #3: Guide Tube .............................................................................. 18
3.3.1
System Description .............................................................................. 18
3.3.2
Analytical Support ............................................................................... 19
iii
3.4
3.5
3.6
3.7
Subsystem #4: Cutting and Stripping............................................................... 20
3.4.1
System Description .............................................................................. 20
3.4.2
Analytical Support ............................................................................... 22
Subsystem #5: Secondary Feed ........................................................................ 24
3.5.1
System Description .............................................................................. 24
3.5.2
Analytical Support ............................................................................... 25
Subsystem #6: Walking Beam ......................................................................... 26
3.6.1
System Description .............................................................................. 26
3.6.2
Analytical Support ............................................................................... 28
Subsystem #7: Bending .................................................................................... 31
3.7.1
System Description .............................................................................. 31
3.7.2
Analytical Support ............................................................................... 33
4. Conclusion ................................................................................................................. 34
5. References.................................................................................................................. 35
6. Appendices ................................................................................................................ 36
6.1
Bill of Materials ............................................................................................... 36
6.1.1
Subsystem #1 Bill of Materials ............................................................ 36
6.1.2
Subsystem #2 Bill of Materials ............................................................ 37
6.1.3
Subsystem #3 Bill of Materials ............................................................ 38
6.1.4
Subsystem #4 Bill of Materials ............................................................ 38
6.1.5
Subsystem #5 Bill of Materials ............................................................ 39
6.1.6
Subsystem #6 Bill of Materials ............................................................ 40
6.1.7
Subsystem #7 Bill of Materials ............................................................ 41
iv
LIST OF TABLES
Table 1: Belt Width Factors for L Section Belt ............................................................... 17
Table 2: PLC Model ........................................................................................................ 36
Table 3: Subsystem #1 BOM ........................................................................................... 36
Table 4: Subsystem #2 BOM ........................................................................................... 37
Table 5: Subsystem #3 BOM ........................................................................................... 38
Table 6: Subsystem #4 BOM ........................................................................................... 38
Table 7: Subsystem #5 BOM ........................................................................................... 39
Table 8: Subsystem #6 BOM ........................................................................................... 40
Table 9: Subsystem #7 BOM ........................................................................................... 41
v
LIST OF FIGURES
Figure 1: General Machine Layout .................................................................................... 2
Figure 2: Full Machine Isometric ...................................................................................... 3
Figure 3: Subsystems #2 through #5 ................................................................................. 4
Figure 4: Subsystem #5 through #7 ................................................................................... 5
Figure 5: Machine Timing Diagram .................................................................................. 7
Figure 6: Subsystem #1 Isometric ..................................................................................... 8
Figure 7: Uncoiling Mechanism Exploded View .............................................................. 9
Figure 8: Primary Feed Mechanism Isometric ................................................................ 14
Figure 9: Primary Feed Mechanism Exploded View ...................................................... 15
Figure 10: Guide Tube Mechanism Isometric ................................................................. 18
Figure 11: Guide Tube Mechanism Exploded View ....................................................... 19
Figure 12: Cutting / Stripping Mechanism Isometric ...................................................... 20
Figure 13: Cutting / Stripping Mechanism Exploded View ............................................ 21
Figure 14: Secondary Feed Mechanisms Isometric ......................................................... 24
Figure 15: Walking Beam Isometric................................................................................ 26
Figure 16: Walking Beam Section View ......................................................................... 27
Figure 17: Bending Mechanism Isometric ...................................................................... 31
Figure 18: Bending Mechanism Section View ................................................................ 32
vi
NOMENCLATUE
Cr
Basic Dynamic Load Rating (lb)
d
Pitch Diameter of Smaller Pulley (in)
D
Outside Diameter of Shaft (in)
f
Frequency (rpm)
F
Force (lb)
Km
Shock and Fatigue Factor Applied to Bending Moment(dimensionless)
Kt
Shock and Fatigue Factor Applied to Torsional Moment(dimensionless)
L10 h
Basic Rating Life (hours)
M
Maximum Bending Moment (in-lbs)
n1
Revolutions Per Minute (rpm)
n2
Revolutions Per Second
N
Full Load Speed (rpm)
pt
Maximum Allowable Shearing Stress Under Combined Loading Conditions (psi)
P
Equivalent Load (lb)
r
Radius (in)
r1
RPM of Faster Shaft Divided by 1000 (rpm)
SY
Material Yield Strength (psi)
t
Time (seconds)
T
Torque (ft-lbs)
W
Weight of Revolving Body (lb)
WR 2
Rotational Inertia (lb-ft2)

Angular Acceleration (rad/sec2)

Coefficient of Friction (dimensionless)
B
Bending Stress

Shear Stress

Angular Velocity (rad/sec)
vii
ACRONYMS
BOM
Bill of Materials
CAD
Computer Aided Design
ID
Inner Diameter
I/O
Input/Output
NEMA
National Electrical Manufacturers Association
OD
Outer Diameter
PLC
Programmable Logic Controller
PN
Part Number
viii
KEY WORDS
Automation
Machine Design
Wire Stripping
Wire Cutting
Wire Bending
ix
ACKNOWLEDGMENT
I would like to thank my family for continued support and inspiration during my
education. I would also like to thank the faculty at RPI Hartford and Troy, especially
Professor Ernesto Gutierrez-Miravete and Professor Larry Ruff, for their guidance.
x
ABSTRACT
The aim of this project is to produce the mechanical design of an automatic machine for
manufacturing segments of heavy gauge insulated electrical wire with both ends stripped
and bent at 90 degrees from a spool stock of insulated electrical wire. These wire
segments would be used in the assembly of electrical components such as battery banks,
prefabricated circuit breaker panels, and other components where jumper/bridge
segments are required. The design of the automatic wire stripping and bending machine
will utilize seven subsystems which together compose the machine. Design of the
machine is performed using Computer Aided Design (CAD) software to produce a 3D
model of the machine. Each subsystem is shown and key design features are discussed
with supporting rational for their implementation. Supporting calculations are performed
to size various components used in each subsystem and load bearing areas throughout
the machine are evaluated for stress. A timing diagram and input/output (I/O) listing is
developed and a programmable logic controller (PLC) model selected to define the
control system. The 3D CAD model allows a potential customer or colleague to produce
2D drawings for manufacture and assembly of the automatic machine.
xi
1. Introduction
1.1 Background
1.1.1
Automation
Automation of a manufacturing process plays a vital role in reducing a company's
production costs. The primary reasons for automating a manufacturing process are
reducing labor costs, reducing waste, improving quality, increasing repeatability,
reducing employee injuries, and allowing uninterrupted production. The project
involving automation of stripping and bending single-conductor electrical wire is
proposed in Reference [1]. A current market need for such a machine exists in the cable
processing industry, as can be seen from the multi-conductor cable cutting and stripping
machine manufactured by Schleuniger of Reference [2].
1.1.2
Machine Function
The function of the automatic wire stripping and bending machine presented in this
report is to produce segments of insulated electrical wire with both ends stripped from a
spool of #12 single-conductor insulated copper wire. These segments are cut to lengths
varying from 5 to 24 inches, and the stripped ends bent 90 degrees. The production rate
of this machine is anticipated to produce a finished segment of wire every five seconds.
The automation of this process serves to replace the manual human operations
previously used to produce a segment of wire as described above. Figure 1, below,
shows the general layout of the seven subsystems, which together compose the machine.
The seven subsystems are:
1. Free Length Uncoiling Subsystem
2. Primary Feed Subsystem
3. Guide Tube Subsystem
4. Cutting and Stripping Subsystem
5. Secondary Feed Subsystem
6. Walking Beam Subsystem
7. Bending Subsystem
1
Figure 1: General Machine Layout
1.2 Problem Description
1.2.1
Requirements and Specifications
The requirements and specifications for the automatic wire stripping and bending
machine are as follows:

Produce wire segments with lengths ranging from 5 inches to 24 inches.

Remove up to 1 inch of insulation from both ends of the wire segment.

Bend both stripped ends of the wire segment 90 degrees in the same direction.

Uncoil insulated wire automatically from spool stock.

Produce a finished wire segment every 5 seconds.

Control the automatic machine through a Programmable Logic Controller (PLC).

Pneumatics of the machine to use 90 psi shop air supply.

Simple manual adjustment for different segment length production runs.

Hands free operation once setup and programmed for specific segment length.

Sensor feedback to stop machine and notify operator when jam or malfunction
occurs.

Machine to be located on bench top when in use.
2
2. Full Machine
2.1 Machine Description
Shown below in Figure 2 is an isometric view of the full assembly of the automatic wire
stripping and bending machine which consists of the seven subassemblies, shown in
Figure 1.
Figure 2: Full Machine Isometric
Each of the seven subsystems which compose the automatic machine is individually
discussed in Chapter 3. Subsystem #1 is mounted to the structure which supports the
spool stock of insulated single-conductor wire and the remaining six subsystems are
mounted to a 38 inch high table.
3
Shown below in Figure 3 is a front view of the Subsystems #2 though #5, where the
drop-slide mechanism of Subsystem #5 is not shown.
Figure 3: Subsystems #2 through #5
The uncoiled wire produced by Subsystem #1 is fed along through the guide tube
(Subsystem #3) by the primary feed (Subsystem #2) and onto the cutting and stripping
mechanism (Subsystem #4). The primary feed also moves the wire in reverse to perform
the stripping operation once the jaws of the cutting and stripping mechanism are
clamped down in the strip position for the leading end of the wire segment. Optical
sensor #1 detects the leading end of each wire segment, thus allowing accurate feed and
measurement of the wire for determining segment length for cutting. The wire length is
determined by the number of rotations the stepper motor for the primary feed undergoes.
The secondary feed (Subsystem #5) is used for feeding the wire segment back into the
cutting and stripping mechanism to strip the second end of the wire segment.
4
Figure 4, below, shows the detail of the secondary feed (Subsystem #5), walking beam
(Subsystem #6), and bending mechanisms (Subsystem #7). Components of the
secondary feed and bending mechanism are not shown for clarity in Figure 4).
Figure 4: Subsystem #5 through #7
Once the wire segment has had the insulating casing stripped from both ends, the ends
are bent at 90 degrees in the same direction. In order to achieve a high production rate,
the process of bending the stripped ends is moved from the path of cutting and stripping.
This is achieved by a walking beam mechanism (Subsystem #6). In Subsystem #5 the
wire is transferred by the secondary feed to a drop slide mechanism. Optical sensor #2
detects the entry of the wire segment into the drop slide. Once optical sensor #2 does not
detect a wire, the wire segment has been fully transferred to the drop slide and the drop
slide can open. If the optical sensor does not clear after a preprogrammed amount of
time, the entire machine is stopped and the operator is notified of a jam. When the drop
slide is opened, the wire segment falls onto the first step of the stationary track of the
walking beam. The walking beam is cycled through one rotation and the bending
5
mechanism (Subsystem #7) performs one cycle. Each cycle of the walking beam moves
the wire segment one increment on the stationary track of the walking beam, through the
bending station, and eventually out of the machine.
The primary components selected for linear actuation are pneumatic cylinders due to
their low cost and compact design. The pneumatic cylinders are all mounted with pivot
points (i.e. clevis, pinned connection) on either end of the cylinder to allow for self
aligning capability. This will minimize wear of the cylinders and allow for greater
tolerances for mounting the actuators.
2.2 Control System
The subject automatic machine is operated by a PLC, as specified in paragraph 1.2.1,
with input signals from two proximity sensors and two optical beam sensors. Figure 5
below shows the timing diagram for the PLC inputs and outputs for the cycle of
producing one wire segment cut to length, both ends stripped and bent at 90 degrees. For
sensors, the sensor input is considered 0 when there is no signal, and 1 when the signal
occurs. A subsystem or actuator is at rest when noted as 0, and in operation when noted
as 1. Using this information, the timing diagram would be used as a guide for
programming the PLC, where each input and output is visually documented for one
cycle of the automation process.
Based on the sequential control required from the timing diagram developed, a PLC is
appropriate for the control system. The Reference [3] CLICK PLC selected for the
subject machine has an operating voltage range of 24 VDC for inputs and 5-27 VDC for
outputs. The inductive proximity sensors used in Subsystem #1 have a voltage range of
10-65 VDC. The light-beam optical sensors used in this machine have a voltage range of
5-24 VDC. Based on the above voltage ranges, the analog signals produced by the
selected sensors are compatible with the selected Reference [3] PLC.
6
Figure 5: Machine Timing Diagram
7
3. Machine Design
3.1 Subsystem #1: Free-Length Uncoiling
3.1.1
System Description
Shown below in Figure 6 is an isometric view of the Subsystem #1 assembly with a
close-up isometric view of the uncoiling mechanism. See Appendix 6.1.1 for a Bill of
Materials (BOM) for Subsystem #1.
Figure 6: Subsystem #1 Isometric
Subsystem #1 uncoils a free-length amount of wire from a spool stock of insulated wire
(Part Number (PN) 1 in Figure 6). The mechanism consists of a drive roller (PN 11 in
Figure 7) with an idle roller (PN 10 in Figure 7) which is tensioned against the insulated
wire by a spring (PN 12 in Figure 7). The drive roller is rotated by a DC electric motor
(PN 3 in Figure 7). The electric motor is coupled to the drive roller shaft with a helical
coupling (PN 4 in Figure 7). The free-length is regulated by two inductive proximity
switches (PN 2 in Figure 6).
8
Shown below in Figure 7 is an exploded view of the uncoiling mechanism for
Subsystem #1.
Figure 7: Uncoiling Mechanism Exploded View
The two proximity switches (PN 2 in Figure 6) are used to provide feedback to the
uncoiling mechanism which uncoils wire from the spool stock (PN 1 in Figure 6). The
proximity switches are located at a set distance vertically apart from each other to
provide a free length of wire 72 inches in length. As the lower sensor detects the wire it
will cause the uncoiling mechanism to stop. Once the free length of wire is consumed
by the machine the free length of wire is shortened to the point where the upper
proximity sensor detects the wire and provides a signal to turn the uncoiling mechanism
on until the wire droops into the detecting space of the lower sensor.
9
3.1.2
Analytical Support
3.1.2.1 Electric Motor
The design of Subsystem #1 is based on uncoiling a 20 inch diameter spool of #12
single-conductor insulated copper wire weighing 62.5 lbs. Subsystem #1 is designed to
uncoil a free-length of wire 72 inches long in 2 seconds. To achieve this requirement, a
20 inch diameter spool must rotate at 35 rpm. For conservatism, a 1 second time to reach
35 rpm is assumed when calculating the required torque. The torque required to rotate
the spool is given by:
T
N  WR 2
t  308
(1)
where 308 is a combined constant converting minutes into seconds, weight into mass
and radius into circumference [4]. The rotational inertia is calculated as 21.7lb  ft 2
from the weight and radius of gyration of the rotating spool. Solving Equation (1) gives
a torque of 2.47 ft  lb .
The pull force required to meet the above torque requirement at the outer perimeter of
the spool is given by:
F
T
r
(2)
Solving Equation (2) using the torque calculated by Equation (1) and the radius of the
spool results in a required pull force of 2.97 lb.
The required minimum torque for the motor (PN 7 in Figure 7) coupled to the 1.7 inch
diameter drive roller (PN 11 in Figure 7) is found by:
TM  F  r
(3)
10
Solving Equation (3) using the pull force calculated in Equation (2) and the radius of the
drive roller results in a torque of 2.52in  lb . Assuming a 25% loss in transmitted torque
from the motor to the drive roller due to friction, the drive motor for Subassembly #1 is
sized to provide a minimum torque of 3.15in  lb . A 25% frictional loss is considered
conservative based on the frictional torque calculated in paragraph 3.6.2.1, and its effect
on the overall torque requirement.
From the results of Equations (1) through (3), a NEMA 23 frame electric stepper motor
[5], as selected in the design, provides sufficient margin for required torque to uncoil 72
inches of wire in 2 seconds. NEMA 23 stepper motors typically range in torque ratings
from 5in  lb to 14in  lb [5]. In addition, the margin for required torque would allow
the spool size to be increased in size and weight.
3.1.2.2 Extension Spring
The clamping force required between the drive rollers is given by:
FN 
F
(4)

Solving Equation (4) using the pull force calculated in Equation (2) and a coefficient of
friction of   0.25 for aluminum with nylon [4] results in a clamping force of 11.88 lb.
The required force from the extension spring at the end of idle roller arm (PN 3 in Figure
7) is found from a sum of moments about the pivot point of the idle roller arm. This
results in selecting an extension spring (PN 12 in Figure 7) which provides a
compressive load of 6 lb.
11
3.1.2.3 Shafts
The transmission shaft (PN 9 in Figure 7) is subjected to torsion and bending due to the
motor torque and tension spring. The required minimum diameter for a transmission
shaft is given by [4, p.301]:
D  B3
5.1
pt
K m M  2  K t T  2
(5)
A maximum bending moment on the transmission shaft of 2.14in  lb is calculated from
the result of Equation (4) and a dimension of 0.18 inch from the center of the roller to
the supporting bearing face. The maximum allowable shearing stress for the combined
stress condition is pt  6000 psi for commercial steel shafts with a keyway [4]. Shock
and fatigue factors of K M  1.5 and K t  1 are selected for a rotating shaft with
gradually applied load and steady operation [4]. A value of 1 for factor B is applied for
solid shafts [4]. Solving Equation (5) using the torque calculated in Equation (3) results
in a minimum shaft diameter of 0.151 inch.
The lineshaft (PN 8 of Figure 7) for the idle roller is subjected only to a bending load.
The required minimum diameter for a line shaft is given by [4, p.301]:
D  B3
10.2 K m M
S
(6)
The maximum allowable bending stress for a bending only condition is S  12,000 psi
for commercial steel shafts with a keyway [4]. Equation (6) is calculated using the same
shock and fatigue factor, B factor, and bending moment as above, resulting in a
minimum shaft diameter of 0.140 inch.
12
The shaft diameter used for both the transmission shaft and lineshaft of Subassembly #1
are similar, with a diameter ranging from 0.25 inch at the coupling between the motor
and transmission shaft to 0.375 inch at the bearings and roller end of the shaft, thus
meeting the minimum diameters calculated by Equations (5) and (6).
3.1.2.4 Bearings
The inner diameter (ID) of the bearings is defined by the shaft size, therefore the
remaining calculations for bearing selection are for life rating. The operating conditions
for the bearings in this subsystem are considered intermittent where failure has
significant effect on function. The basic rating life L10 h is recommended to be a
minimum of 8000 to 12000 hours for this condition [6]. The basic rating life in operating
hours is calculated by [6]:
16667  Cr 
L10h 
 
n1
 P
3
(7)
The equivalent load, P , is the vector sum of the tangential and radial forces on the shaft,
and is equal to 17.94 lbs. The basic dynamic load rating, C r , is 356 lbs for a single rowflanged bearing with a 0.375 inch ID and 0.875 inch outer diameter (OD) [7]. The rpm,
n , at the shaft is calculated from the resultant linear speed of the wire when it is
uncoiled from the spool at 35 rpm, and is equal to 411.77 rpm. Solving Equation (7)
gives a basic rating life of 316,290 hrs for the bearings selected to support the
transmission shaft, which meets the basic rating life recommended above. The same
bearings are used to support the idle roller shaft, and are acceptable because the
equivalent load is less when compared to the transmission shaft.
13
3.2 Subsystem #2: Primary Feed
3.2.1
System Description
Shown below in Figure 8 is an isometric view of the Subsystem #2 assembly. See
Appendix 6.1.2 for a BOM for Subsystem #2.
Figure 8: Primary Feed Mechanism Isometric
The primary feed mechanism, Subsystem #2, draws insulated wire from the free length
of wire maintained by Subsystem #1. This wire is fed along through the guide tube of
Subsystem #3 and onto the cutting and stripping mechanism of Subsystem #4.
Subsystem #2 also moves the wire in reverse to perform the stripping operation once the
jaws of Subsystem #4 are clamped down in the strip position. The wire length is
determined by the number of rotations the drive rollers undergo to accurately measure
the length of wire to be cut by Subsystem #4.
14
Shown below in Figure 9 is an exploded view of the Subsystem #2 assembly.
Figure 9: Primary Feed Mechanism Exploded View
The drive rollers of this mechanism are driven by an electric stepper motor (PN 1 in
Figure 9), timing pulleys (PN 11 in Figure 9), and timing belt (PN 4 in Figure 9). An
idle pulley (PN 9 in Figure 9) attached to a tension block (PN 7 in Figure 9) is used to
tension to the timing belt and provide engagement across the two timing pulleys. The
tension block functions by housing two compression springs guided by two shoulder
bolts with bushings (PNs 5, 6 and 8 in Figure 9). The lower idle rollers (PN 13 in Figure
9) are mounted to a floating housing which is tensioned against the drive rollers in a
similar fashion as the timing belt tension block described above. The lower idle rollers
provide a compressive load against the insulated wire and drive rollers, thus preventing
slip in the drive mechanism.
15
3.2.2
Analytical Support
3.2.2.1 Electric Motor
It is assumed that a 25 lb force is required to pull the insulation off of the copper wire
once the insulation has been cut by Subsystem #4. Solving Equation (3) with a tangential
force of 25 lb and a 0.85 inch radius of the drive roller results in a torque of
21.25in  lb . Assuming a 25% loss in transmitted torque from the motor to the drive
rollers due to friction, the drive motor for Subassembly #2 is sized to provide a
minimum torque of 26.56in  lb . A NEMA 34 frame electric stepper motor with 3
stacks providing 62.19in  lb [5], as selected in the design, provides sufficient margin
for required torque of Subassembly #2.
3.2.2.2 Compression Springs
Solving Equation (4) using the pull force assumed in paragraph 3.2.2.1 and a coefficient
of friction of   0.25 for aluminum with nylon [4] results in a clamping force of 100
lb. It is calculated that the idle roller housing assembly (PN 14 in Figure 9) with all
components is 2 lb. Two compression springs are used in the design of Subassembly #2
for tensioning the idle rollers; therefore, from a sum of forces each compression spring is
selected to provide 51 lb of force.
3.2.2.3 Shafts
The clamping force calculated in paragraph 3.2.2.2 is distributed across three idle rollers.
A maximum bending moment on each transmission shaft (PN 8 in Figure 9) of
28.43in  lb is calculated from the clamping force calculated in paragraph 3.2.2.2 and a
dimension of 0.853 inch from the center of the idle roller to the supporting bearing face.
Solving Equation (5) using the motor torque calculated in paragraph 3.2.2.1 and the
factors for transmission shafts with keyways used in paragraph 3.1.2.3 results in a
minimum shaft diameter of 0.350 inch.
The load condition experienced by the lineshafts supporting the idle rollers in
Subassembly #2 is less severe than the transmission shafts. Therefore by comparison, an
0.375 inch diameter for both transmission shafts and lineshafts is sufficient.
16
3.2.2.4 Bearings
The ID of the bearings is defined by the shaft size; therefore the remaining calculations
for bearing selection are for life rating. The equivalent load P is the vector sum of the
tangential and radial forces on the shaft, and is equal to 41.66 lbs. The basic dynamic
load rating, C r , is 356 lbs for a single row- flanged bearing with a 0.375 inch ID and
0.875 inch outer diameter (OD) [7]. The rpm, n , is calculated to be 200 rpm to be able
to feed 24 inches of wire in 2 seconds with 1.7 inch diameter rollers.
The operating conditions for the bearings in this subsystem are considered to be 8 hours
of continuous operation. The basic rating life L10 h is recommended to be a minimum of
20,000 to 30,000 hours for this condition [6]. Solving Equation (7) gives a basic rating
life of 52,002 hrs for the bearings selected to support the transmission shaft, which meets
the basic rating life recommended above.
3.2.2.5 Synchronous Belt
The maximum horsepower rating recommended for a 1 inch wide L section belt (0.375
inch pitch) is calculated by [4, p.2449]:

L(1.00) HP  dr1 0.436  3.01 10 4 dr1 
2

(8)
Solving Equation (8) using a pitch diameter of 1.432 inch (12L timing pulley) and a 200
rpm as specified in paragraph 3.2.2.4 results in 0.13 HP. The width of the synchronous
belt is reduced by applying a width factor from Table 1 [8] to the maximum horsepower
rating calculated by Equation (8). Applying the factor for a 3/4 inch wide L section belt
results in an maximum horsepower rating of 0.0923 HP.
Table 1: Belt Width Factors for L Section Belt
Belt Width
¾”
7/8”
1”
Width Factor
0.71
0.86
1.0
17
Horsepower as a function of torque (in in  lbs ) and rpm is calculated by:
HP 
T  rpm
63,025
(9)
Solving Equation (9) with the torque calculated in paragraph 3.2.2.1 results in a
horsepower of 0.084 HP. As such, a 3/4 inch wide L section belt and a 12L pulley is
acceptable for transferring the calculated power.
3.3 Subsystem #3: Guide Tube
3.3.1
System Description
Shown below in Figure 10 is an isometric view of the Subsystem #3 assembly. See
Appendix 6.1.3 for a BOM for Subsystem #3.
Figure 10: Guide Tube Mechanism Isometric
18
Shown below in Figure 11 is an exploded view of the Subsystem #3 assembly.
Figure 11: Guide Tube Mechanism Exploded View
The funneled guide tube (PN 6 in Figure 11) guides the insulated wire to the
stripping/cutting station (Subsystem #4) and performs additional straightening of the
wire. The funneled tube is interchangeable for different gauge wire and is mounted to a
solenoid (PN 4 in Figure 11) actuated rotation assembly. The rotation of the guide tube
allows for the leading end of the following wire to be moved out of the way when a
segment of wire is back-fed into the stripping/cutting station for the second stripping
operation. The solenoid is mounted in a housing (PN 3 in Figure 11) which rotates on
shoulder bolts (PN 2 in Figure 11). The rotation of the housing is required to prevent
binding in the mechanism when the solenoid extends.
3.3.2
Analytical Support
3.3.2.1 Push Type Solenoid
A desired rotation speed for the guide tube shaft (PN 5 in Figure 11) of 600 rpm to be
reached in 0.5 sec is assumed and a weight of 0.85 lb for the shaft, guide tube housing
19
(PN 7 in Figure 11), and guide tube is calculated. Solving Equation (1) gives a required
torque of 0.0115 ft  lbs . The available torque from the selected solenoid, mounted to
the 1.151 inch lever arm (PN 1 in Figure 11), which rotates the shaft, is 7.12in  lbs . The
solenoid selected and the lever arm it actuates provides an ample amount of margin.
3.4 Subsystem #4: Cutting and Stripping
3.4.1
System Description
Shown below in Figure 12 is an isometric view of the Subsystem #4 assembly. See
Appendix 6.1.4 6.1 for a BOM for Subsystem #4.
Figure 12: Cutting / Stripping Mechanism Isometric
Subsystem #4 performs the cutting and stripping operations for both the leading and rear
ends of the wire segment. The cutting and stripping operations are performed by a set of
dies which are actuated by a linear cam mechanism.
20
Shown below in Figure 13 is an exploded view of the Subsystem #4 assembly.
Figure 13: Cutting / Stripping Mechanism Exploded View
The linear cam plate (PN 1 in Figure 13) is actuated by a pneumatic cylinder (PN 7 in
Figure 13), which produces a clamping motion via cam followers (PN 2 in Figure 13) on
each of the cutter arms (PN 4 in Figure 13). The stripping/cutting die (PN 3 in Figure
13) is interchangeable for different gauge wires. The initial end of the wire is fed into
the stripping station, the jaws contract over the wire with the dies. This stripping
position is set by and intermediate stop which is engaged by a smaller pneumatic
cylinder (PN 5 in Figure 13).
Once the insulation is cut, the feed mechanism of
Subsystem #2 rotates in reverse to pull the insulation off the end of the wire.
The wire is then fed forward for a predetermined segment length and captured by the
secondary feed mechanism (Subsystem #5). The wire is cut by allowing the pneumatic
cylinder (PN 7 in Figure 13) attached to the linear cam plate to go through its entire
stroke. In order to strip the second end of the wire segment, the guide tube of Subsystem
21
#3 is rotated upwards, the feed mechanism of Subsystem #5 feeds the segment in reverse
through the stripping jaws where the action described in the paragraph above is
performed again.
3.4.2
Analytical Support
3.4.2.1 Cutter Arms
A worst case stress condition for the cutter arms (PN 4 in Figure 13) is considered to be
when Subsystem #2 or #5 pull the wire segment to perform the stripping operation on
the wire ends. A Von Mises Stress Criterion is used for evaluating stress:
 Von   B2  3 2
(10)
The stripping operation creates a 25 lb force at the cutting tip of the cutting blade. The
horizontal section of the cutter arm has a cross-sectional area of 0.25in 2 , and is the load
bearing area. A bending stress of 2928 psi is calculated from the moment induced at the
horizontal section of the cutter arm. In addition, a shear stress of 100 psi is calculated at
the horizontal section. Solving Equation (10) results in a combined stress of 2933.12
psi, which is below the yield strength of 40 ksi for 6061-T6 aluminum.
3.4.2.2 Cutter Blades
The worst case stress condition for the cutter blades (PN 3 in Figure 13) is the same as
the condition described in paragraph 3.4.2.1. The horizontal section of the cutter blade
has a cross-sectional area of 0.0625in 2 . A bending stress of 13,324.8 psi is calculated
from the moment induced at the horizontal section of the cutter blade that is unsupported
by the cutter arm. In addition, a shear stress of 400 psi is calculated. Solving Equation
(10) results in a combined stress of 13,342.8 psi, which is below the yield strength of 55
ksi for High Strength 1045 Medium-Carbon Steel.
22
3.4.2.3 Pneumatics
The force required to shear wire is calculated by:

P  C SY d 2

(11)
where C  1 for solid wire [9].
The diameter of solid copper for #12 gauge wire is 0.081 inch [4]. The yield strength of
CW003A copper wire and similar highly conductive copper alloys is approximately 10
ksi. CW003A copper wire is assumed to be representative of the material used for
segments of insulated wire being manufactured by the subject machine. Solving
Equation (11) results in a 65.61 lb force. The pneumatic cylinder (PN 7 of Figure 13)
selected for the design is a 1.25 inch bore double-acting pneumatic cylinder and provides
108.7 lb of force [10]. This force is translated to the cam followers (PN 2 of Figure 13)
where the cam followers travel in slots angled at 20.61 . The cutting force is the vertical
vector component of the resultant force normal to the cam slots. Solving for the vertical
component results in cutting force of 266 lb. As such, the 1.25 inch bore double-acting
pneumatic cylinder selected in the design provides a factor of safety of 4 for cutting
force.
23
3.5 Subsystem #5: Secondary Feed
3.5.1
System Description
Shown below in Figure 14 is an isometric view of the Subsystem #5 assembly. See
Appendix 6.1.5 for a BOM for Subsystem #5.
Figure 14: Secondary Feed Mechanisms Isometric
The purpose of Subsystem #5 is to provide the driving mechanism for stripping the rear
end of the insulated wire segment and then transfer the stripped wire segment to the
walking beam conveyor of Subsystem #6. The secondary drive mechanism (PN 1 in
Figure 14) is identical to the one shown in Figure 9 because the function of this drive is
essentially identical to that of Subsystem #2. A guide tube (PN 8 in Figure 14) is
attached to the housing of the drive mechanism to accurately guide the rear end into the
cutting blades of Subsystem #4 and to ensure the wire segment is captured by the drive
mechanism of Subsystem #5. A drop slide mechanism (PNs 2 through 6 in Figure 14) is
used to capture the wire segment with both ends stripped of insulation. The drop slide
mechanism consists of a hinged sheet metal plate (PN 2 in Figure 14) which can
24
accommodate lengths of wire 5 inches through 24 inches without adjustment. The drop
slide is opened by a pneumatic cylinder (PN 4 in Figure 14), allowing the wire to fall
onto the first step of the stationary portion of the walking beam mechanism (Subsystem
#6).
A slot-type optical sensor (PN 8 in Figure 14) is mounted between the drive mechanism
and the drop slide. The sensor allows the machine to sense when the segment of wire has
been completely transferred to the drop slide. The optical sensor detects the leading end
of the wire segment and then the absence of a wire segment between feed mechanism
and drop slide. The drop slide is then opened by retracting the stroke of the pneumatic
cylinder (PN 4 in Figure 14) and the wire segment is then transferred to Subsystem #6.
3.5.2
Analytical Support
3.5.2.1 Pneumatics
The weight of the hinged sheet (PN 2 in Figure 14) is calculated to be 0.76 lb. A desired
rotation speed for the hinged plate (PN 9 in Figure 14) of 600 rpm to be reached in 0.5
sec is assumed. Solving Equation (1) using a the radius of gyration for the 0.24 inch
diameter pivot points about which the hinged sheet rotates results in a required torque of
0.021 ft  lbs 0.26in  lbs  . The available torque from the selected 5/16 inch pneumatic
cylinder, mounted at a location which produces a
1.47 inch lever arm,
is 5.29in  lbs [10]. The selected cylinder is sufficient rotating the hinged sheet of the
drop slide mechanism.
25
3.6 Subsystem #6: Walking Beam
3.6.1
System Description
Shown below in Figure 15 is an isometric view of the Subsystem #6 assembly. See
Appendix 6.1.6 for a BOM for Subsystem #6.
Figure 15: Walking Beam Isometric
The walking beam mechanism is used to move the stripped wire segment from the path
of cutting and stripping to the bending station and finally to an area on the table where
the finished product is collected. The bending station (Subsystem #7) is incorporated
over the stationary portion of the walking beam (PN 13 in Figure 16) and is discussed in
paragraph 3.7.1.
26
Shown below in Figure 16 is a section view of the working components in the
Subsystem #6 assembly.
Figure 16: Walking Beam Section View
The walking beam (PN 14 in Figure 16) is cycled by rotating four eccentric hubs (PN 15
in Figure 16). Each rotation of the walking beam moves the wire segment one increment
on the stationary track of the walking beam (PN 13 in Figure 16). The rotation of the
hubs is driven by an electric motor (PN 1 in Figure 15) and timing belts (PN 10 in Figure
15). Rotation from the electric motor to the rotating hubs is transferred via a solenoid
activated clutch (PN 2 in Figure 15). The motor operates constantly and when a wire
segment is dropped from drop slide of Subsystem #5, the clutch is engaged for one
revolution of the walking beam. The walking beam is adjustable for lengths of wire 4
inches to 24 inches by turning an acme screw (PN 4 in Figure 15), which will move the
moving assembly housing (PN 8 in Figure 15) along two liner slides (PN 7 in Figure 15).
The adjustable side of the walking beam is driven by a hex shaft (PN 3 in Figure 16)
through hex bushings (PN 16 in Figure 16).
27
3.6.2
Analytical Support
3.6.2.1 Electric Motor
Eccentric Hub and Moving Beam:
The parallel axis theorem is used to find the moment of inertia for calculating torque to
rotate the moving beam (PN 14 in Figure 16) traveling in an eccentric path:
I C  I G  me2
(12)
where:
IG 
1 2
mr
2
(13)
The rotating mass of the eccentric hubs, hub caps, and moving beams with associated
hardware is 3 lb. The outside diameter of each eccentric hub is 2.36 inch with the axis of
the cam bore in the hub offset by 0.19 inch from the center axis of the hub. The desired
cycle time for each rotation of the walking-beam is 1 revolution every 2 seconds which
equals 3.14rad / sec . Torque is given by:
T  I
(14)
Solving Equations (12), (13), and (14) results in a torque of 6.9in  lbs . A centrifugal
force is induced on the bearings due to the eccentric rotation of the moving beam.
Centrifugal force is calculated by:
FC  1227WRn 22
(15)
The centrifugal force produces a dynamic radial load on the bearings, resulting in
additional torque to overcome friction.
28
Frictional torque is calculated by:
TF 
1
Pd
2
(16)
The coefficient of friction for radial ball bearings is   0.0015 [11]. Solving Equations
(15) and (16) results in a frictional torque of 0.026in  lbs .
Drive Components:
The moment of inertia for the rotating parts of model SCB-5 clutch/brake selected in this
design is I  0.236lb  in 2 . The moment of inertia for the rotating parts remaining in the
drive system which were not accounted for above is I  0.925lb  in 2 . The moments of
inertia for the drive components are combined and Equation (14) is solved, resulting in a
torque of 3.65in  lbs . Frictional forces are assumed negligible for the torque to rotate
the drive components due to very minimal dynamic loads anticipated in this system.
Total Torque Requirement:
Combining the torques calculated to rotate the dive components, eccentric hubs, moving
beams, and frictional torque results in a torque of TTotal  10.58in  lbs . As discussed in
paragraph 3.2.2.1, a NEMA 34 frame electric stepper motor [5], as selected in the
design, provides sufficient margin for required torque.
3.6.2.2 Bearings
The ID of the bearing is defined by the hub OD; therefore the remaining calculations for
bearing selection are for life rating. The dynamic load of P  14.57lb is the centrifugal
force created by eccentric rotation. The basic dynamic load rating, C r , is 1960 lb for a
single row- bearing with a 2.36 inch ID and 3.07 inch OD [7]. The rpm, n , is calculated
to be 30 rpm from the criteria defined in paragraph 3.6.2.1.
29
The operating conditions for the bearings in this subsystem are considered to be 8 hours
of continuous operation. The basic rating life L10 h is recommended to be a minimum of
12,000 to 20,000 hours for this condition [6]. Solving Equation (7) gives a basic rating
life of 1.35  109 hrs for the bearings selected to support the transmission shaft, which
meets the basic rating life recommended above.
3.6.2.3 Synchronous Belt
The maximum horsepower rating recommended for a 0.38 inch wide XL section belt
(0.200 inch pitch) is calculated by [4, p.2449]:

L(0.38) HP  dr1 0.0916  7.07 105 dr1 
2

(17)
Solving Equation (17) using a pitch diameter of 1.783 inch (28XL timing pulley) and a
30 rpm as specified in paragraph 3.6.2.2 results in 0.005 HP. Solving Equation (9) with
the torque calculated in paragraph 3.2.2.1 results in a horsepower of 0.005 HP. As such,
a 0.38 inch wide XL section belt and a 28XL pulley is acceptable for transferring the
calculated power.
30
3.7 Subsystem #7: Bending
3.7.1
System Description
Shown below in Figure 17 is an isometric view of the Subsystem #7 assembly. See
Appendix 6.1.76.1 for a BOM for Subsystem #7.
Figure 17: Bending Mechanism Isometric
Subsystem #7 performs the operation which bends both stripped ends of the wire
segment 90 degrees in the same direction. Once the wire drops down from Subsystem #5
and onto the first increment of the walking beam, two pneumatic cylinders with
rectangular push plates (PN 1 Figure 17) alternate their strokes and align the wire
segment for the bending operation.
31
Shown below in Figure 18 is a section view of the working components in the
Subsystem #7 assembly.
Figure 18: Bending Mechanism Section View
The bending of both stripped ends is completed by actuating two dies (PN 5 in Figure
18) vertically down with pneumatic cylinders (PN 3 in Figure 18). The dies are slightly
offset from the edge of the walking beam stationary rail to account of the thickness of
the un-insulated wire. A spring loaded guide block (PN 7 in Figure 18) is incorporated
into the die to prevent the wire from moving during the bending operation. The die is
mounted on a linear slide (PN 2 in Figure 17) to provide smooth, rigid motion. This
subsystem is mounted directly to Subsystem #6 so no adjustment is required for different
lengths of wire segments.
After the bending operation is complete, the part will be removed during the next cycle
of the walking beam (Subsystem #6) and dropped on a slide where the wire segments
can be collected in a bin.
32
3.7.2
Analytical Support
3.7.2.1 Pneumatics
From the material specifications and properties described in paragraph 3.4.2.3, the
copper wire undergoing the bending operation has a yield strength of 10 ksi and has a
diameter of 0.081 inch. The moment of inertia for a solid circular section is calculated
by:
I
d 4
(18)
64
The bending stress is calculated by:
b 
Mc
I
(19)
The length of un-insulated copper wire to be bent is 1 inch. Assuming a 10 lb force is
acting at 0.5 inches from the supporting edge of the stationary portion of the walking
beam (PN 13 in Figure 16); solving Equations (18) and (19) results in a bending stress of
96 ksi. Since the bending stress is higher than the yield strength of the material, plastic
deformation will occur. The calculated mass of all components (PNs 4 through 7 in
Figure 18) attached to the piston of the pneumatic cylinder is 2.67 lb. The 5/8 inch bore
double acting cylinder (PN 3 in Figure 18) selected in the design provides a clamping
force of 27.2 lb and a return force of 20.3 lb [10]. As such, the selected cylinder provides
sufficient forces for bending wire and returning the bending mechanism to the initial
position.
33
4. Conclusion
The concepts behind the design of the seven subsystems, which together as a whole
function as the wire stripping and bending automatic machine, are to produce a product
which would require minimal setup time for different wire segment lengths, hands free
operation, and minimal maintenance. In the original brainstorming concepts, off the
shelf pneumatic grippers and multi-position pneumatic slides were used. These ideas
were not implemented due to the thought that it would result in cumbersome machine
setup and programming, greater cost, and possibly greater maintenance requirements.
Based on the analytical support presented in this report, the components designed and
selected for the automatic wire stripping and bending machine are sufficient for
performing the motions of the machine without failure.
The future work involving the subject project would be contingent upon a customer or
colleague with an intent to manufacture the subject machine. From the 3D model
presented in this report 2D drawings for manufacturing custom parts and assembly of the
machine can be created. Remaining parts required to assemble the machine would be
purchased from the selected vendors using the BOMs listed in Appendices 6.1.1 through
6.1.7.
34
5. References
[1]
Derby, Stephen J, Design of Automatic Machinery. Marcel Dekker, New York,
2005
[2]
http://www.youtube.com/watch?v=ox8F12oD7_M, Schleuniger MegaStrip 9600.
[3]
Automation Direct, Basic CLICK CPU Module Specifications, Volume 14, C000DD2-D
[4]
Oberg, Jones, Horton, Ryffel, Machinery's Handbook, 28th ed. Industrial Press,
New York, 2008.
[5]
Pacific Scientific, Hybrid Step Motors. November, 2000.
[6]
www.ASTBearings.com, Document No. ENB-04-0637, AST Bearings LLC,
New Jersey, 2011.
[7]
http://precisionparts.wmberg.com/bearings. BERG. Cudahy, WI.
[8]
Jason Industrial, Inc. Drive Design Manual, HTB and Standard Synchronous
Belts.
[9]
J.A. Schey, Introduction to Manufacturing Processes, 3rd ed. McGrawHill,
Boston, 2000.
[10]
Festo, Compact Cylinders ADVU/AEVU, Standard Cylinders DSNU ISO 6432
[11]
www.smbbearings.com,
Bearing
Technical
Kingdom.
35
Information.
Oxon,
United
6. Appendices
6.1 Bill of Materials
Items identified by ( - ) are required to be custom made; therefore no manufacturer or
manufacturer PN is provided.
Table 2: PLC Model
PN
Quantity
Description
-
1
CLICK PLC
6.1.1
Manufacturer
Automation
Direct
Manufacturer PN
C0-00DD2-D
Subsystem #1 Bill of Materials
Table 3: Subsystem #1 BOM
PN
Quantity
Description
Manufacturer
Manufacturer PN
1
1
Wire Spool
McMaster-Carr
7125K421
2
2
Proximity Sensor
Turck
Bi10U-G30-AN4X-H1141
3
1
Pacific Scientific
22NR
4
1
Helical Coupling
SDP/SI
S50HAD-100H0808
5
4
Flange Bearing
Berg
B2-8-S-Q3
6
1
Shoulder Bolt
McMaster-Carr
91259A578
7
1
Pivot Arm
-
-
8,9
1
Shafts
-
-
10,11
1
Pulleys
-
-
12
1
Tension Spring
McMaster-Carr
9433K57
NEMA 23
Stepper Motor
36
6.1.2
Subsystem #2 Bill of Materials
Table 4: Subsystem #2 BOM
PN
Quantity
1
1
2
1
3
Description
Manufacturer
Manufacturer PN
Pacific Scientific
33NR
Helical Coupling
SDP/SI
S50HAD-100H1212
12
Flange Bearing
Berg
B2-8-S-Q3
4
1
Timing Belt
McMaster-Carr
6484K244
5
2
Shoulder Bolt
McMaster-Carr
91259A634
6
2
Bushings
-
-
7
1
Tension Block
-
-
8
4
Compression Spring
McMaster-Carr
9657K377
9
1
Idle Pulley
McMaster-Carr
3668K14
10
2
Shaft
-
-
11
2
Timing Pulley
12,13
6
Roller
-
-
14
1
Idle Block
-
-
NEMA 34 Stepper
Motor
B&B
Manufacturing
37
12L075-6FS5
6.1.3
Subsystem #3 Bill of Materials
Table 5: Subsystem #3 BOM
PN
Quantity
Description
Manufacturer
Manufacturer PN
1
1
Lever Arm
-
-
2
2
Shoulder Bolt
McMaster-Carr
91259A578
3
1
Pivot Block
-
-
4
1
Solenoid
Magnet-Schultz
S-06805
5
1
Shaft
-
-
6
1
Guide Tube
-
-
7
1
Guide Tube Housing
-
-
8
2
Flange Bearing
Berg
B2-8-S-Q3
6.1.4
Subsystem #4 Bill of Materials
Table 6: Subsystem #4 BOM
PN
Quantity
Description
Manufacturer
Manufacturer PN
1
1
Cam Plate
-
-
2
2
Cam Follower
McMaster-Carr
3668K24
3
2
Die
-
-
4
2
Cutter Arm
-
-
5
1
Pneumatic Cylinder
Festo
156 500
6
1
Rod Clevis
Festo
6 144
7
1
Pneumatic Cylinder
Festo
156 617
8
1
Optical Sensor
Omron
EE-SX914-R
38
6.1.5
Subsystem #5 Bill of Materials
Table 7: Subsystem #5 BOM
PN
Quantity
1
1
2
1
3
Description
Manufacturer
Manufacturer PN
-
-
Hinged Metal Sheet
-
-
2
Clevis Mount
Festo
6057
4
1
Pneumatic Cylinder
Festo
19177
5
1
Rod Eye
Festo
9253
6
1
-
-
7
1
Optical Sensor
Omron
EE-SX914-R
8
1
Guide Tube
-
-
Same as Subsystem
#2
Stationary Metal
Sheet
39
6.1.6
Subsystem #6 Bill of Materials
Table 8: Subsystem #6 BOM
PN
Quantity
1
1
2
1
3
Description
Manufacturer
Manufacturer PN
Pacific Scientific
33NR
Clutch/Brake
Warner Electric
SCB-5
1
Hex Shaft
SDP/SI
A 7X21-1036
4
1
Acme Threaded Rod
McMaster-Carr
99030A126
5
1
Flanged Bearing
McMaster-Carr
5912K14
6
1
Hand Wheel
McMaster-Carr
8515K5
7
2
Linear Guide
THK
SRS9WM
8
1
-
-
9
1
-
-
10
4
Timing Belt
McMaster-Carr
1679K23
11
4
Housing Shaft
-
-
12
8
Timing Pulley
13
1
Rod Clevis
Festo
6 144
14
2
Moving Beam
-
-
15
4
Eccentric Hub
-
-
16
2
Hex Coupling
SDP/SI
A 7C20-10
17
8
Flanged Bearing
Berg
B2-8-S-Q3
18
8
Ball Bearing
SKF
61812
19
4
Internal C-Clip
McMaster-Carr
99142A645
20
2
External C-Clip
McMaster-Carr
97633A300
21
4
Ball Bearing
McMaster-Carr
6384K84
22
2
External C-Clip
McMaster-Carr
97633A230
NEMA 34 Stepper
Motor
Moving Assembly
Housing
Stationary Assembly
Housing
B&B
Manufacturing
40
28XL037-6FA3
6.1.7
Subsystem #7 Bill of Materials
Table 9: Subsystem #7 BOM
PN
Quantity
Description
Manufacturer
Manufacturer PN
1
2
Thread in Cylinder
Festo
015038
2
2
Linear Guide
THK
SRS9M
3
2
Pneumatic Cylinder
Festo
156 597
4
2
Festo
2062
5
2
Die
-
-
6
2
Compression Spring
McMaster-Carr
7
2
Guide Block
-
Self-Aligning Rod
Coupler
41
-