Difference between revisions of "Group 21 - Black and Decker Drill"

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==Executive Summary==  
 
==Executive Summary==  
[[Image:DR202_1.jpg|thumb|Description]]
+
[[Image:DR202_1.jpg|thumb|Black and Decker DR202]]
Carpenters, craftsman, and the all around handy man need a tool that is capable of placing screws into material accurately, and reliably.  Utilizing a powered drill is the most viable option because the drill provides mechanical advantages that far surpass the conventional screw driver.  With the slight pull of the trigger a powered drill is capable of providing many foot pounds of torque that is capable of placing screws into various materials accurately and effectively.
+
Carpenters, craftsman, and the all around handy man need a tool that is capable of placing screws into material accurately, and reliably.  Utilizing a powered drill is the most viable option because the drill provides mechanical advantages that far surpass the conventional screw driver.  With the slight pull of the trigger a powered drill can provide many foot pounds of torque that are capable of placing screws into various materials accurately and effectively.
  
By carefully analyzing the Black and Decker DR202 it is clear to see why this drill has been a consumer favorite over the years.  At first glance one may be attracted to the black and red color scheme that has became the standard for Black and Decker products.  The outer covering is made of a sturdy plastic along with rubber grips for added comfort and control.  Other features that help to separate the Black and Decker DR202 from other powered drills on the market are the level on the back of the drill as well as a keyless chuck.  Taking a closer look under the outer casing a powerful 5 Amp motor is utilized to provide adequate power for the toughest jobs.   
+
By carefully analyzing the Black and Decker DR202 it is clear to see why this drill has been a consumer favorite over the years.  At first glance one may be attracted to the black and red color scheme that has became the standard for Black and Decker products.  The outer covering is made of a sturdy plastic along with rubber grips for added comfort and control.  Other features that help to separate the Black and Decker DR202 from other powered drills on the market is the level on the back of the drill as well as the key-less chuck.  Taking a closer look under the outer casing a powerful 5 Amp motor is utilized to provide adequate power for the toughest jobs.   
  
 
Granted, Black and Decker has created a drill that accurately and reliably drills screws into various materials there is still room for improvement.  By disassembling and reviewing the manufacture processes, material type, and function of ease individual component of the DR202 our team was able to suggest some design changes.  These design changes could be implemented to keep the Black and Decker DR202 drill on the top of the competitive marketplace.
 
Granted, Black and Decker has created a drill that accurately and reliably drills screws into various materials there is still room for improvement.  By disassembling and reviewing the manufacture processes, material type, and function of ease individual component of the DR202 our team was able to suggest some design changes.  These design changes could be implemented to keep the Black and Decker DR202 drill on the top of the competitive marketplace.
  
==Introduction==
+
==Before Disassembly Section==
 +
 
 +
===Introduction:===
 
The objective of this project was to examine the Black and Decker DR202 powered drill.  By disassembling, reassembling, and reviewing the inner workings of the drill our group was successfully able to grasp how the DR202 was manufactured and how to improve upon the design of the DR202.
 
The objective of this project was to examine the Black and Decker DR202 powered drill.  By disassembling, reassembling, and reviewing the inner workings of the drill our group was successfully able to grasp how the DR202 was manufactured and how to improve upon the design of the DR202.
 +
  
 
Our group was a collaboration of five dedicated individuals whose contributions are noted below
 
Our group was a collaboration of five dedicated individuals whose contributions are noted below
  
Andrew Klahr (group leader)-List contributions here<br>
 
Anne-Marsha Joseph- List contributions here<br>
 
Katie Weber- List contributions here<br>
 
Anthony Beeman - List contributions here<br>
 
Yan Liang-List contributions here<br>
 
  
==Before Disassembly Section==
+
Andrew Klahr (group leader)- Presentation, Parts Analysis<BR>
 +
Anne-Marsha Joseph- Presentation, Disassembly<BR>
 +
Katie Weber- Disassembly, Part Analysis<BR>
 +
Anthony Beeman - WIKI Page, Reassembly<BR>
 +
Yan Liang- CAD Drawings, Reassembly<BR>
  
<b>Purpose:</b><BR>
+
===Purpose:===
 
The purpose of the Black and Decker DR202 was to fasten and remove screws into materials such as drywall, sheet rock, and wood.  The DR202 is able to accurately and reliably place screws into various materials with the aid of the level that is provided on the drill.  Drill bits can be removed by utilizing the keyless chuck.  The DR202 chuck is capable of holding drill bits that fall within the range of 1–10 mm.  Each bit can perform specific functions when utilized with the DR202.  For example some bits are used to create holes in materials while other bits can be utilized to drive screws into materials.  The DR202 is powered by 120 volts of alternating current and has the capability of rotating clock wise as well as counter clockwise.
 
The purpose of the Black and Decker DR202 was to fasten and remove screws into materials such as drywall, sheet rock, and wood.  The DR202 is able to accurately and reliably place screws into various materials with the aid of the level that is provided on the drill.  Drill bits can be removed by utilizing the keyless chuck.  The DR202 chuck is capable of holding drill bits that fall within the range of 1–10 mm.  Each bit can perform specific functions when utilized with the DR202.  For example some bits are used to create holes in materials while other bits can be utilized to drive screws into materials.  The DR202 is powered by 120 volts of alternating current and has the capability of rotating clock wise as well as counter clockwise.
  
<b>Components:</b><BR>
+
===Components:===
 
Our group estimated the DR202 powered drill would consist of 30 parts.  Some of these parts are listed below:<BR>
 
Our group estimated the DR202 powered drill would consist of 30 parts.  Some of these parts are listed below:<BR>
 
1 Directional Switch<BR>
 
1 Directional Switch<BR>
Line 35: Line 37:
 
9 Bit<BR>
 
9 Bit<BR>
  
<b>Materials:</b><BR>
+
===Materials:===
 
Prior to disassembling the Black and Decker DR202 our group believed the power drill consisted of 4 types of materials.<BR>
 
Prior to disassembling the Black and Decker DR202 our group believed the power drill consisted of 4 types of materials.<BR>
 
1 Copper<BR>
 
1 Copper<BR>
Line 43: Line 45:
  
 
==Disassembly Procedure==
 
==Disassembly Procedure==
 
+
<BR>
 +
<BR>
 
{| border="3" cellspacing="0" cellpadding="3" align="center"
 
{| border="3" cellspacing="0" cellpadding="3" align="center"
 
! width="50"|Step #
 
! width="50"|Step #
Line 52: Line 55:
 
|-
 
|-
 
| align="center" |1
 
| align="center" |1
| align="center" |Type Description Here
+
| align="center" |Took out the nine screws.
| align="center" |Type Tools Used Here
+
| align="center" |Flathead Screwdriver
| align="center" |Type Level of Difficulty Here
+
| align="center" |Moderately Difficult
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |2
 
| align="center" |2
| align="center" |Type Description Here
+
| align="center" |Pried the plastic bit holder out.
| align="center" |Type Tools Used Here
+
| align="center" |Flathead Screwdriver
| align="center" |Type Level of Difficulty Here
+
| align="center" |Easy
|-
+
  
 
|-
 
|-
 
| align="center" |3
 
| align="center" |3
| align="center" |Type Description Here
+
| align="center" |Separated the right side of the casing from the left side of the casing. As doing so the directional lever fell out.
| align="center" |Type Tools Used Here
+
| align="center" |Hands
| align="center" |Type Level of Difficulty Here
+
| align="center" |Easy
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |4
 
| align="center" |4
| align="center" |Type Description Here
+
| align="center" |Placing the left side of the casing down, we pulled the motor and attachments out of the casing.
| align="center" |Type Tools Used Here
+
| align="center" |Hands
| align="center" |Type Level of Difficulty Here
+
| align="center" |Easy
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |5
 
| align="center" |5
| align="center" |Type Description Here
+
| align="center" |Removed two more screws which were holding a metal plate down, which was holding the wires leading to the cord in place.
| align="center" |Type Tools Used Here
+
| align="center" |Flathead Screwdriver
| align="center" |Type Level of Difficulty Here
+
| align="center" |Moderately Difficult
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |6
 
| align="center" |6
| align="center" |Type Description Here
+
| align="center" |Pulled out the chuck and attached gears.
| align="center" |Type Tools Used Here
+
| align="center" |Hands
| align="center" |Type Level of Difficulty Here
+
| align="center" |Easy
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |7
 
| align="center" |7
| align="center" |Type Description Here
+
| align="center" |Separated the gear system from the motor.
| align="center" |Type Tools Used Here
+
| align="center" |Hands
| align="center" |Type Level of Difficulty Here
+
| align="center" |Easy
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |8
 
| align="center" |8
| align="center" |Type Description Here
+
| align="center" |Separated the individual gears that made up the gear system.
| align="center" |Type Tools Used Here
+
| align="center" |Hands
| align="center" |Type Level of Difficulty Here
+
| align="center" |Easy
 
|-
 
|-
 
 
 
|}
 
|}
 +
<BR>
 +
<BR>
  
 
==After Disassembly==
 
==After Disassembly==
 
+
<BR>
 
+
===Parts Table===
 +
<BR>
 
{| border="3" cellspacing="0" cellpadding="3" align="center"
 
{| border="3" cellspacing="0" cellpadding="3" align="center"
! width="20" |Part #
+
! width="20" |Part Number
! width="75" |Part
+
! width="120" |Part Name
! width="50" |Quantity
+
! width="50" |Quanity
! width="100" |Material
+
! width="170" |Materials
! width="75" |Manufacturing Process
+
! width="150" |Manufacture Process
 
! width="250" |Purpose
 
! width="250" |Purpose
 
! width="150" |Picture
 
! width="150" |Picture
  
 
|-
 
|-
| align="center" |Type Part Number Here
+
| align="center" |1
| align="center" |Type Part Name Here
+
| align="center" |outer casing (left)
| align="center" |Type Quanity
+
| align="center" |1
| align="center" |Type Material Here
+
| align="center" |PA6/G40 plastic and rubber
| align="center" |Type Manufacturing Process Here
+
| align="center" |Injection Molded
| align="center" |Type Purpose of Part Here
+
| align="center" |Cover is made to hold the inner parts.
| align="center" |Insert Picture Here
+
| align="center" |[[Image:outercasingleft.JPG|thumb|Left Outer Casing]]
 
|-
 
|-
  
 +
|-
 +
| align="center" |2
 +
| align="center" |outer casing (right)
 +
| align="center" |1
 +
| align="center" |PA6/G40 plastic and rubber
 +
| align="center" |Injection Molded
 +
| align="center" |Cover is made to hold the inner parts.
 +
| align="center" |[[Image:outercasingright.JPG|thumb|Right Outer Casing]]
 +
|-
  
 
|-
 
|-
| align="center" |Type Part Number Here
+
| align="center" |3
| align="center" |Type Part Name Here
+
| align="center" |3/4" Screws with #15 Torx heads
| align="center" |Type Quanity
+
| align="center" |9
| align="center" |Type Material Here
+
| align="center" |Steel
| align="center" |Type Manufacturing Process Here
+
| align="center" |Extruded and Machined 
| align="center" |Type Purpose of Part Here
+
| align="center" |Holds separate components together
| align="center" |Insert Picture Here
+
| align="center" |[[Image:34inchscrew.JPG|thumb|3/4" Screws]]
 
|-
 
|-
  
  
 
|-
 
|-
| align="center" |Type Part Number Here
+
| align="center" |4
| align="center" |Type Part Name Here
+
| align="center" |1 7/8" Screws with #15 Torx heads
| align="center" |Type Quanity
+
| align="center" |2
| align="center" |Type Material Here
+
| align="center" |Steel
| align="center" |Type Manufacturing Process Here
+
| align="center" |Extruded and Machined
| align="center" |Type Purpose of Part Here
+
| align="center" |Holds separate components together
| align="center" |Insert Picture Here
+
| align="center" |[[Image:178inchscrew.JPG|thumb|1 7/8" Screws]]
 
|-
 
|-
 +
  
  
 
|-
 
|-
| align="center" |Type Part Number Here
+
| align="center" |5
| align="center" |Type Part Name Here
+
| align="center" |Bit Holder
| align="center" |Type Quanity
+
| align="center" |1
| align="center" |Type Material Here
+
| align="center" |Plastic
| align="center" |Type Manufacturing Process Here
+
| align="center" |Injection Molded
| align="center" |Type Purpose of Part Here
+
| align="center" |Holds one bit
| align="center" |Insert Picture Here
+
| align="center" |[[Image:bitholder.JPG|thumb|Bit Holder]]
 
|-
 
|-
  
 +
|-
 +
| align="center" |6
 +
| align="center" |Bubble Level
 +
| align="center" |1
 +
| align="center" |Plastic
 +
| align="center" |Extruded
 +
| align="center" |Bubble level is used to ensure the user that the screw is being driven into the material at a right angle.
 +
| align="center" |[[Image:BubbleLevel.JPG|thumb|Bubble Level]]
 +
|-
  
 
|-
 
|-
| align="center" |Type Part Number Here
+
| align="center" |7
| align="center" |Type Part Name Here
+
| align="center" |Directional Lever
| align="center" |Type Quanity
+
| align="center" |1
| align="center" |Type Material Here
+
| align="center" |Plastic
| align="center" |Type Manufacturing Process Here
+
| align="center" |Injection Molded
| align="center" |Type Purpose of Part Here
+
| align="center" |Allows the drill to spin clockwise and counter clockwise.
| align="center" |Insert Picture Here
+
| align="center" |[[Image:Directionallever.JPG|thumb|Directional Lever]]
 
|-
 
|-
 
  
 
|-
 
|-
| align="center" |Type Part Number Here
+
| align="center" |8
| align="center" |Type Part Name Here
+
| align="center" |Double sided bit
| align="center" |Type Quanity
+
| align="center" |1
| align="center" |Type Material Here
+
| align="center" |Steel
| align="center" |Type Manufacturing Process Here
+
| align="center" |Extruded and Machined
| align="center" |Type Purpose of Part Here
+
| align="center" |Insertion of Phillips and flat head screws
| align="center" |Insert Picture Here
+
| align="center" |[[Image:bit.JPG|thumb|Drill Bit]]
 
|-
 
|-
  
  
 
|-
 
|-
| align="center" |Type Part Number Here
+
| align="center" |9
| align="center" |Type Part Name Here
+
| align="center" |Power Cord
| align="center" |Type Quanity
+
| align="center" |1
| align="center" |Type Material Here
+
| align="center" |Plastic<BR>Copper
| align="center" |Type Manufacturing Process Here
+
| align="center" |Extruded
| align="center" |Type Purpose of Part Here
+
| align="center" |Provide AC current to the power inverter
| align="center" |Insert Picture Here
+
| align="center" |[[Image:powercord.JPG|thumb|Power Cord]]
 
|-
 
|-
  
  
 
|-
 
|-
| align="center" |Type Part Number Here
+
| align="center" |10
| align="center" |Type Part Name Here
+
| align="center" |Inverter
| align="center" |Type Quanity
+
| align="center" |1
| align="center" |Type Material Here
+
| align="center" |Plastic<BR>Copper<BR>Woven glass
| align="center" |Type Manufacturing Process Here
+
| align="center" |Injection molding<BR>Silk screen printing<BR>Photoengraving<BR>PCB milling
| align="center" |Type Purpose of Part Here
+
| align="center" |Converts current from AC to DC allowing the motor to utilize the provided current.
| align="center" |Insert Picture Here
+
| align="center" |[[Image:inverter.JPG|thumb|Inverter]]
 
|-
 
|-
  
  
 
|-
 
|-
| align="center" |Type Part Number Here
+
| align="center" |11
| align="center" |Type Part Name Here
+
| align="center" |Trigger
| align="center" |Type Quanity
+
| align="center" |1
| align="center" |Type Material Here
+
| align="center" |Plastic
| align="center" |Type Manufacturing Process Here
+
| align="center" |Injection Molded
| align="center" |Type Purpose of Part Here
+
| align="center" |Utilized as switch to open and close the circuit.
| align="center" |Insert Picture Here
+
| align="center" |[[Image:trigger22.JPG|thumb|Trigger]]
 
|-
 
|-
  
  
 
|-
 
|-
| align="center" |Type Part Number Here
+
| align="center" |12
| align="center" |Type Part Name Here
+
| align="center" |Internal Wiring
| align="center" |Type Quanity
+
| align="center" |2
| align="center" |Type Material Here
+
| align="center" |Copper<BR>Plastic (Insulation)
| align="center" |Type Manufacturing Process Here
+
| align="center" |Extruded
| align="center" |Type Purpose of Part Here
+
| align="center" |Transport current from the inverter to the motor.
| align="center" |Insert Picture Here
+
| align="center" |[[Image:wires.JPG|thumb|Wires]]
 
|-
 
|-
  
  
 
|-
 
|-
| align="center" |Type Part Number Here
+
| align="center" |13
| align="center" |Type Part Name Here
+
| align="center" |Motor
| align="center" |Type Quanity
+
| align="center" |1
| align="center" |Type Material Here
+
| align="center" |Steel<BR>Plastic<BR>Copper
| align="center" |Type Manufacturing Process Here
+
| align="center" |Machined
| align="center" |Type Purpose of Part Here
+
| align="center" |Spins Shaft that rotates the gear system.
| align="center" |Insert Picture Here
+
| align="center" |[[Image:Motor499.JPG|thumb|Motor]]
 
|-
 
|-
  
  
 
|-
 
|-
| align="center" |Type Part Number Here
+
| align="center" |14
| align="center" |Type Part Name Here
+
| align="center" |Cooling Fan
| align="center" |Type Quanity
+
| align="center" |1
| align="center" |Type Material Here
+
| align="center" |Plastic
| align="center" |Type Manufacturing Process Here
+
| align="center" |Machined
| align="center" |Type Purpose of Part Here
+
| align="center" |Keeps motor from overheating.
| align="center" |Insert Picture Here
+
| align="center" |[[Image:coolfan499.JPG|thumb|Cooling Fan]]
 
|-
 
|-
  
 +
|-
 +
| align="center" |15
 +
| align="center" |Key Less Chuck
 +
| align="center" |1
 +
| align="center" |Plastic
 +
| align="center" |Injection Molding<BR>Metal Casting
 +
| align="center" |Holds a bit that can be removed by the user.
 +
| align="center" |[[Image:keylesschuck499.JPG|thumb|Chuck]]
 +
|-
 +
 +
|-
 +
| align="center" |16
 +
| align="center" |Gear System<BR>(Table Below)
 +
| align="center" |1
 +
| align="center" |Steel
 +
| align="center" |Noted On Gear System Table
 +
| align="center" |Through a series of gear reductions the gear system creates a torque.
 +
| align="center" |[[Image:gearsystem499.JPG|thumb|Gear System]]
 +
|-
 
|}
 
|}
 +
<BR>
  
 +
===Gear System Table===
 +
<BR>
 +
{| border="3" cellspacing="0" cellpadding="3" align="center"
 +
! width="20" |Part Number
 +
! width="120" |Part Name
 +
! width="50" |Quanity
 +
! width="170" |Materials
 +
! width="150" |Manufacture Process
 +
! width="250" |Purpose
 +
! width="150" |Picture
  
===3D Computer Aided Design===
+
|-
[[Image:pic.JPG|thumb|Description]]
+
| align="center" |17
 +
| align="center" |Motor Shaft
 +
| align="center" |1
 +
| align="center" |Stainless Steel
 +
| align="center" |Extruded
 +
| align="center" |Connects to the motor to rotate the gear system.
 +
| align="center" |[[Image:MotorShaft.JPG|thumb|Motor Shaft]]
 +
|-
  
==Assembly==
+
|-
 +
| align="center" |18
 +
| align="center" |Plate (a)
 +
| align="center" |1
 +
| align="center" |Stainless Steel
 +
| align="center" |Metal Casting
 +
| align="center" |Fits firmly onto the outer casing in order to secure the motor shaft.
 +
| align="center" |[[Image:Platea.JPG|thumb|Plate (a)]]
 +
|-
  
  
 +
|-
 +
| align="center" |19
 +
| align="center" |Plate (b)
 +
| align="center" |1
 +
| align="center" |Stainless Steel
 +
| align="center" |Metal Casting
 +
| align="center" |Fits firmly onto the outer casing in order to secure the motor shaft.
 +
| align="center" |[[Image:Plateb.JPG|thumb|Plate (b)]]
 +
|-
 +
 +
|-
 +
| align="center" |20
 +
| align="center" |Gear
 +
| align="center" |1
 +
| align="center" |Stainless Steel
 +
| align="center" |Machined
 +
| align="center" |Connects to the motor shaft to rotate the gear and pinion.
 +
| align="center" |[[Image:gear499.JPG|thumb|Gear]]
 +
|-
 +
 +
|-
 +
| align="center" |21
 +
| align="center" |Gear and Pinion
 +
| align="center" |1
 +
| align="center" |Stainless Steel
 +
| align="center" |Machined
 +
| align="center" |Connects to the gear in order to create a torque.
 +
| align="center" |[[Image:gearandpinion499.JPG|thumb|Gear and Pinion]]
 +
|-
 +
|}
 +
 +
===3D Computer Aided Design===
 +
<BR>
 +
<BR>
 +
{| border="3" cellspacing="0" cellpadding="3" align="center"
 +
! width="175" |Assembly Part 1
 +
! width="175" |Assembly Part 2
 +
! width="175" |Assembly Part 3
 +
! width="175" |Final Assembly
 +
|-
 +
| align="center" |[[Image:assemblypart1.JPG|thumb|]]
 +
| align="center" |[[Image:assemblypart22.JPG|thumb|]]
 +
| align="center" |[[Image:assemblypart33.JPG|thumb|]]
 +
| align="center" |[[Image:CadGearSystem2.JPG|thumb|]]
 +
|-
 +
|-
 +
|}
 +
<BR>
 +
<BR>
 +
 +
==Assembly==
 +
<br>
 +
<br>
 
{| border="3" cellspacing="0" cellpadding="3" align="center"
 
{| border="3" cellspacing="0" cellpadding="3" align="center"
 
! width="50"|Step #
 
! width="50"|Step #
Line 269: Line 388:
 
|-
 
|-
 
| align="center" |1
 
| align="center" |1
| align="center" |Type Description Here
+
| align="center" |Connect the individual gears that made up the gear system.
| align="center" |Type Tools Used Here
+
| align="center" |Hands
| align="center" |Type Level of Difficulty Here
+
| align="center" |Easy
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |2
 
| align="center" |2
| align="center" |Type Description Here
+
| align="center" |Place motor into the left cover.
| align="center" |Type Tools Used Here
+
| align="center" |Hands
| align="center" |Type Level of Difficulty Here
+
| align="center" |Difficult
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |3
 
| align="center" |3
| align="center" |Type Description Here
+
| align="center" |Place the gear system into the left cover.
| align="center" |Type Tools Used Here
+
| align="center" |Hands
| align="center" |Type Level of Difficulty Here
+
| align="center" |Easy
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |4
 
| align="center" |4
| align="center" |Type Description Here
+
| align="center" |Place the two screws into the metal plate and used them to secure the wires within the left cover.
| align="center" |Type Tools Used Here
+
| align="center" |Phillips Screwdriver
| align="center" |Type Level of Difficulty Here
+
| align="center" |Easy
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |5
 
| align="center" |5
| align="center" |Type Description Here
+
| align="center" |Place inverter and trigger back into left cover.
| align="center" |Type Tools Used Here
+
| align="center" |Hands
| align="center" |Type Level of Difficulty Here
+
| align="center" |Easy
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |6
 
| align="center" |6
| align="center" |Type Description Here
+
| align="center" |Connect the directional lever to the motor.
| align="center" |Type Tools Used Here
+
| align="center" |Hands
| align="center" |Type Level of Difficulty Here
+
| align="center" |Moderate
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |7
 
| align="center" |7
| align="center" |Type Description Here
+
| align="center" |Place right cover over the drill.
| align="center" |Type Tools Used Here
+
| align="center" |Hands
| align="center" |Type Level of Difficulty Here
+
| align="center" |Easy
 
|-
 
|-
  
 
|-
 
|-
 
| align="center" |8
 
| align="center" |8
| align="center" |Type Description Here
+
| align="center" |Place 9 screws into Left cover and connected left and right cover.
| align="center" |Type Tools Used Here
+
| align="center" |Phillips Screwdriver
| align="center" |Type Level of Difficulty Here
+
| align="center" |Easy
 
|-
 
|-
 
 
 
|}
 
|}
 +
<br>
 +
<br>
  
 
==After Assembly==
 
==After Assembly==
 +
<br>
 +
===How It Works===   
 +
After disassembling the product, the function of each part, as well as how the overall
 +
product operated, was accessed.<BR>
 +
           
 +
This drill has a universal motor. It runs off of an alternating current (AC) power supply,
 +
which comes from an outlet. The motor contains a rotor that has copper wire wrapped around it. The copper wire is used to create a magnetic field. As the AC power is supplied to the rotor, it creates a magnet. The rotor is also surrounded by another magnet with the north pole of the rotor’s magnet attached to the south of the additional magnet. According to the magnetic theory, the opposite poles of each magnet attract each other, while the like poles repel each other. With this relationship, the two magnets begin to repel each other, which cause the rotor to turn. The motor is also made up of small pieces of metal called “brushes”. These brushes rub against a disk that’s attached to the shaft. When the AC power is supplied to the motor and the rotor turns due to the magnetic forces, the brushes transfer electricity to the shaft, which causes it to turn. As the shaft rotates, it causes the gears to turn as well, which then makes the chuck rotate. As the user applies force to the drill and the chuck rotates, the screw enters the targeted material. There is a cooling fan attached to the shaft that helps keep the motor from overheating. It also rotates as the shaft rotates.  After reassembling the drill, it ran the same as it did before the disassembly.<BR>
  
*Does it still work?
+
<BR>
*Conclusion remarks
+
  
==References==
+
===Product Analysis===
[http://www.apastyle.org/ APA Style]
+
<BR>
You must use this format (It's easier than MLA, so don't worry).
+
  
===Guide to Writing Wiki Code===
+
----
  
The beauty about Wiki is that if you don't know the code, you can steal it from someone's page that does. Feel free to click the "edit" links or tabs to view the code for sections or the pages respectively. Be weary about wrecking havoc on another's page. Each page can be rollbacked to a previous verison and your username is linked to all changes. Although you might think it's cool to go through and insert "MIKE RULES" throughout the page, I'm sure Dr. Lewis would not be pleased.
+
<b>Note To The Reader:</b>  <i>The purpose of this product analysis is to walk you through the engineering thought process while solving the analytical problem noted below.</i>
  
<b>Here's a few tips on writing with Wiki:</b>
+
----
 +
<BR>
 +
<BR>
 +
<b>Problem Statement:</b>    Calculate the max torque of the Black and Decker DR202 gear system.
 +
<BR>
 +
<BR>
 +
{| border="3" cellspacing="0" cellpadding="3" align="Left"
 +
! width="200" |Gear System
 +
! width="200" |Free Body Diagram
 +
|-
 +
| align="center" |[[Image:fbd1231.JPG|thumb|]]
 +
| align="center" |[[Image:fbd2345.JPG|thumb|]]
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|-
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|-
 +
|}
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<BR>
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<BR>
 +
<BR>
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<BR>
 +
<BR>
 +
<BR>
 +
<BR>
 +
<BR>
 +
<BR>
 +
<BR>
 +
<BR>
 +
<BR>
 +
<i>Please Note:  positive X is to the left, positive Y points up, and a positive moment is counter clockwise.</i>
 +
<BR>
 +
<BR>
 +
<b>Assumptions:</b><BR>
 +
Motor will provide an initial torque (Represented by "m" on the FBD)<BR>
 +
Gears in the gear system are different sizes<BR>
 +
Motor is capable of providing a torque that turns the gear<BR>
 +
Gears don't slip while rotating<BR>
 +
The motors torque doesn't vary with time<BR>
 +
All surfaces are frictionless<BR>
  
This is a bracket "[" "]"
+
<BR>
 +
<b>Governing Equations:</b><BR>
 +
(Sum of the systems angular moment)01 +(Sum system angular impulse)0(1-2) =(Sum system angular momentum)02<BR>
 +
Moment of Inertia: I=m*r*r<BR>
 +
Angular Moment of Inertia:  L=I*w<BR>
 +
Torque  =  moment of inertia * angular acceleration<BR>
 +
<BR>
 +
<b>Calculations</b><BR>
 +
The calculations to the gear system would require extensive understanding of many dynamics concepts and will be explained in the discussion<BR>
 +
<BR>
  
 +
<b>Solutions Check</b><BR>
 +
One would verify numerical values as well as unit consistency.
 +
<BR>
 +
<BR>
 +
<b>Discussion</b><BR>
 +
By calculating the angular moment of inertia and angular acceleration "w" of each gear one could then sum the torques of gear system in a piecewise manner.  The sum of the torques would be the final output torque of the systems.  Torques rotating counter clock wise would be considered positive while torques rotating clock wise would be considered negative.  By varying the gear ratios and the initial torque of the motor one could vary the output torque of the system.  The assumptions make sense when calculating the max torque of the system.  One benefit of this system is that it can be adapted to calculate the torque as a function of time; the motor torque varies.  In order to calculate the torque at a given time the motors torque would have to be  illustrated by a function M(t). This function would be non-linear in nature due to the exponential increase in the motor torque over time; Until the max moment is reached.  By carefully analyzing and optimizing the system above a new max torque could be created.
 +
<BR>
 +
<BR>
 +
===Ergonomic Analysis===
 +
<BR>
 +
By testing the user interaction with the product, concepts such as center of balance and user comfort can be tested.  With the use of a working prototype the analysis can take place.  Issues such as grip comfort and handling of the drill can be addressed.
 +
<BR>
  
This is a brace "{" "}"
+
===Disassembly/Assembly Discussion===
   
+
The disassembly and assembly procedures were the reverse of each other. The disassembly process was very easy and only required the use of a flat head screw driver and our hand. Once we had opened the casing the process was very easy because the housing of the drill was the only component holding the parts in place besides 2 screws on the inside. The assembly process was more time consuming due to the fact that each part had to be put back together in working order, which with the aligning the gear system, the process was somewhat tedious. The same tools were used in both the disassembly and reassembly process.  The drill is back together in working order, same as when we received it prior to disassembly.
  
To create a new page/link within Wiki:
+
===Recommended Design Changes===
*Double brackets, page name, double brackets
+
The drill has a few small weakness in its design. With the following recommended design changes, the product will be more appealing to the user:
*Typing in a new page name will automatically create a page, which when clicked, you can then edit.
+
*Whatever name you first type in is the name of the page. You can't change page names, only create new pages. Think before you create a new page.
+
1. Directional Changer - The directional changer was very large and awkward to use. With a simple button or small sliding mechanism, the directional changer would be much easier to use.
*Don't worry about slashes or anything, all pages are located in the same directory. If I wanted to create a page called "MAE 277 Template" the code would be ''[[''MAE 277 Template'']]'' Note: Brackets are italicized to prevent creating a new page.
+
  
 +
2. Screws - Black and Decker uses two different types of screws that both contain hexagonal screw heads. With the use of phillips or flat-head screws, repairs and disassembly would be much easier. Also, eliminating the the different screws and replacing them with a uniform design would be more cost effective for Black and Decker. 
  
Your table of contents is created automatically.
+
3. Cord - A battery operating drill is a more practical design choice. The cord seems to just get in the way and a battery operated drill does not limit the use of where the drill can be used.  
*1,2,3,4 are level 2 sections
+
*1.1, 1.2, 1.3 are level 3 headers
+
  
 +
4. Drill bit - The bit that is included with the drill is a very basic design. The use of a magnetic bit, or a bit with a sleeve over it would be more user friendly.
  
To create headers:
+
==References==
*Section titles are wrapped with two equal signs ''==''My favorite header''==''
+
<BR>
*Bold headers within a section are wrapped with three equal signs ''===''My not-so-favorite header''===''
+
Black And Decker. (2007) . <i>Instruction Manual for Models DR202 Power Drill.</i>. Retrieved November 7, 2007, from the World Wide Web: http://www.blackanddecker.com<BR>
 
+
Power Drill. (2007) . <i>Power Drill Principles</i>. Retrieved November 13, 2007, from the World Wide Web:  http://home.howstuffworks.com/power-drill.htm<BR>
 
+
How Gear Ratios Work. (2007) . <i>How Gear Ratios Work</i>. Retrieved November 15, 2007, from the World Wide Web:  http://science.howstuffworks.com/gear-ratio4.htm<br>
Asterisks indicate bullets. Be sure to put each asterisk on a new line.
+
How Electric Motors Work.  (2007) . <i>How Electric Motors Work</i>. Retrieved November 15, 2007, from the World Wide Web: http://electronics.howstuffworks.com/motor1.htm<BR>
*Here's one
+
Hibbeler, R. C. (2006). Engineering Mechanics Statics and Dynamics  (11th ed.). St. Louis, MO: Prentice Hall.<BR>
*Here's two *Here's three, but its not on the next line
+
 
+
 
+
Bold text:
+
*Start line with "b" in "<>". Be sure to end the line with "/b" in "<>" if you don't want the whole paragraph to be bold.
+
*Surround text to be bolded with three " ' " marks on either side. Or highlight the text and click the "B" button on the toolbar.
+
 
+
 
+
Italics:
+
*"i" in "<>". Don't forget to end with "/i" in "<>"
+
*Highlight the text and click the "I" button in the toolbar (It will put four " ' " on either side).
+
 
+
 
+
 
+
[[Media:Media File Link|This is a broken link media file caption]]
+
 
+
 
+
Media tags are indicated by "Media:", images by "Image:" Broken links in red. Case is not important. Use the toolbar to get examples if you're not sure.
+
 
+
 
+
Spacing is werid in wiki.  
+
Single return does nothing.
+
 
+
Double return (blank line), breaks the line.
+
 
+
 
+
Triple return (two blank lines), puts an extra blank line between lines of text.
+
 
+
 
+
"br" in "<>" will break lines. They can also be used to separate section headers.
+
 
+
<br><br>
+
Finally, use the <i>"Show Preview"</i> button on the bottom of the page to see how it looks before saving. It will allow you to catch and edit your errors without having to edit the page again. <b>Just don't forget to save it when you're really done.</b>
+
 
+
===This is an example table===
+
 
+
{| border="1" align="center"
+
|+ '''This is the table title'''
+
! width="75"|This is Column Header 1
+
! width="400"|This is Column Header 2
+
! width="200"|This is Column Header 3
+
|-
+
! This starts Row 1
+
| align="center"|Width values (pixels) in header are used to designate the width of the column for the entire table. Text will wrap but it helps to control the layout. Height of the row is determined by the row's largest content
+
| A return and single vertical lines separate columns in rows. A double vertical line is necessary if you don't break up the text for cells.
+
|-
+
! This starts Row 2
+
|align="center"|"br" in brackets<br> break lines. Wiki sometimes ignores blank lines.
+
|align="center"|Some html tags can be used, but not many. Notice the align equals center tag at the beginning of the row. It centers the text in the first two columns, but doesn't work for the third column. I don't know why. Adding the tag again to the beginning of the cell in question will center the text.
+
|-
+
! This starts Row 3
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|align="center"|Image tags are in this format:
+
<br>Double brackets "[["
+
<br>Image name
+
<br>| = Vertical Line
+
<br><br>The following order is not important, as long as each is separated by a vertical line:
+
*Horizontal position (left, center, right)
+
*Thumb (to create clickable thumbnail that links to fullsize image), don't include to make a fullsize
+
*Size denoted in pixels (if desired)
+
*You can add a caption if there is a thumbnail
+
<br>Then close with double brackets "]]"
+
<br><br>Broken links show up in red.
+
<br>[[Image:This is a broken link|center|thumb|150px]]
+
<br>[http://gicl.cs.drexel.edu/wiki/Special:Imagelist Here's where you can view any uploaded files]
+
|[[Image:Camera disassembly 2.jpg|center|thumb|150px|This is thumbnail]]
+
[[Image:Camera disassembly 4.jpg|center|150px]]
+
<br>This is a resized image, not a thumbnail, but notice you can still click on it to get the full size.
+
|-
+
! This starts Row 4
+
|align="center"|Notice the repeating code for every row? It's important. A vertical line and a dash indicate the start of a new row. An exclamation point indicates the first column. You can put the entire row onto a single line, but it's easier to read if you break it up. Again, wiki usually ignores new paragraphs.
+
|Make sure to end the table correctly (vertical line and closed brace). Not doing so might still display the table, but nothing that comes afterwards.
+
|}
+

Latest revision as of 14:30, 10 December 2007

Contents

Executive Summary

Black and Decker DR202

Carpenters, craftsman, and the all around handy man need a tool that is capable of placing screws into material accurately, and reliably. Utilizing a powered drill is the most viable option because the drill provides mechanical advantages that far surpass the conventional screw driver. With the slight pull of the trigger a powered drill can provide many foot pounds of torque that are capable of placing screws into various materials accurately and effectively.

By carefully analyzing the Black and Decker DR202 it is clear to see why this drill has been a consumer favorite over the years. At first glance one may be attracted to the black and red color scheme that has became the standard for Black and Decker products. The outer covering is made of a sturdy plastic along with rubber grips for added comfort and control. Other features that help to separate the Black and Decker DR202 from other powered drills on the market is the level on the back of the drill as well as the key-less chuck. Taking a closer look under the outer casing a powerful 5 Amp motor is utilized to provide adequate power for the toughest jobs.

Granted, Black and Decker has created a drill that accurately and reliably drills screws into various materials there is still room for improvement. By disassembling and reviewing the manufacture processes, material type, and function of ease individual component of the DR202 our team was able to suggest some design changes. These design changes could be implemented to keep the Black and Decker DR202 drill on the top of the competitive marketplace.

Before Disassembly Section

Introduction:

The objective of this project was to examine the Black and Decker DR202 powered drill. By disassembling, reassembling, and reviewing the inner workings of the drill our group was successfully able to grasp how the DR202 was manufactured and how to improve upon the design of the DR202.


Our group was a collaboration of five dedicated individuals whose contributions are noted below


Andrew Klahr (group leader)- Presentation, Parts Analysis
Anne-Marsha Joseph- Presentation, Disassembly
Katie Weber- Disassembly, Part Analysis
Anthony Beeman - WIKI Page, Reassembly
Yan Liang- CAD Drawings, Reassembly

Purpose:

The purpose of the Black and Decker DR202 was to fasten and remove screws into materials such as drywall, sheet rock, and wood. The DR202 is able to accurately and reliably place screws into various materials with the aid of the level that is provided on the drill. Drill bits can be removed by utilizing the keyless chuck. The DR202 chuck is capable of holding drill bits that fall within the range of 1–10 mm. Each bit can perform specific functions when utilized with the DR202. For example some bits are used to create holes in materials while other bits can be utilized to drive screws into materials. The DR202 is powered by 120 volts of alternating current and has the capability of rotating clock wise as well as counter clockwise.

Components:

Our group estimated the DR202 powered drill would consist of 30 parts. Some of these parts are listed below:
1 Directional Switch
2 Gears
3 Motor
4 Cord
5 Outer Casing
6 Chuck
7 Power Trigger
8 Screws
9 Bit

Materials:

Prior to disassembling the Black and Decker DR202 our group believed the power drill consisted of 4 types of materials.
1 Copper
2 Steel
3 Plastic
4 Rubber

Disassembly Procedure



Step # Description Tool(s) Level of Difficulty
1 Took out the nine screws. Flathead Screwdriver Moderately Difficult
2 Pried the plastic bit holder out. Flathead Screwdriver Easy
3 Separated the right side of the casing from the left side of the casing. As doing so the directional lever fell out. Hands Easy
4 Placing the left side of the casing down, we pulled the motor and attachments out of the casing. Hands Easy
5 Removed two more screws which were holding a metal plate down, which was holding the wires leading to the cord in place. Flathead Screwdriver Moderately Difficult
6 Pulled out the chuck and attached gears. Hands Easy
7 Separated the gear system from the motor. Hands Easy
8 Separated the individual gears that made up the gear system. Hands Easy



After Disassembly


Parts Table


Part Number Part Name Quanity Materials Manufacture Process Purpose Picture
1 outer casing (left) 1 PA6/G40 plastic and rubber Injection Molded Cover is made to hold the inner parts.
Left Outer Casing
2 outer casing (right) 1 PA6/G40 plastic and rubber Injection Molded Cover is made to hold the inner parts.
Right Outer Casing
3 3/4" Screws with #15 Torx heads 9 Steel Extruded and Machined Holds separate components together
3/4" Screws
4 1 7/8" Screws with #15 Torx heads 2 Steel Extruded and Machined Holds separate components together
1 7/8" Screws
5 Bit Holder 1 Plastic Injection Molded Holds one bit
Bit Holder
6 Bubble Level 1 Plastic Extruded Bubble level is used to ensure the user that the screw is being driven into the material at a right angle.
Bubble Level
7 Directional Lever 1 Plastic Injection Molded Allows the drill to spin clockwise and counter clockwise.
Directional Lever
8 Double sided bit 1 Steel Extruded and Machined Insertion of Phillips and flat head screws
Drill Bit
9 Power Cord 1 Plastic
Copper
Extruded Provide AC current to the power inverter
Power Cord
10 Inverter 1 Plastic
Copper
Woven glass
Injection molding
Silk screen printing
Photoengraving
PCB milling
Converts current from AC to DC allowing the motor to utilize the provided current.
Inverter
11 Trigger 1 Plastic Injection Molded Utilized as switch to open and close the circuit.
Trigger
12 Internal Wiring 2 Copper
Plastic (Insulation)
Extruded Transport current from the inverter to the motor.
Wires
13 Motor 1 Steel
Plastic
Copper
Machined Spins Shaft that rotates the gear system.
Motor
14 Cooling Fan 1 Plastic Machined Keeps motor from overheating.
Cooling Fan
15 Key Less Chuck 1 Plastic Injection Molding
Metal Casting
Holds a bit that can be removed by the user.
Chuck
16 Gear System
(Table Below)
1 Steel Noted On Gear System Table Through a series of gear reductions the gear system creates a torque.
Gear System


Gear System Table


Part Number Part Name Quanity Materials Manufacture Process Purpose Picture
17 Motor Shaft 1 Stainless Steel Extruded Connects to the motor to rotate the gear system.
Motor Shaft
18 Plate (a) 1 Stainless Steel Metal Casting Fits firmly onto the outer casing in order to secure the motor shaft.
Plate (a)
19 Plate (b) 1 Stainless Steel Metal Casting Fits firmly onto the outer casing in order to secure the motor shaft.
Plate (b)
20 Gear 1 Stainless Steel Machined Connects to the motor shaft to rotate the gear and pinion.
Gear
21 Gear and Pinion 1 Stainless Steel Machined Connects to the gear in order to create a torque.
Gear and Pinion

3D Computer Aided Design



Assembly Part 1 Assembly Part 2 Assembly Part 3 Final Assembly
Assemblypart1.JPG
Assemblypart22.JPG
Assemblypart33.JPG
CadGearSystem2.JPG



Assembly



Step # Description Tool(s) Level of Difficulty
1 Connect the individual gears that made up the gear system. Hands Easy
2 Place motor into the left cover. Hands Difficult
3 Place the gear system into the left cover. Hands Easy
4 Place the two screws into the metal plate and used them to secure the wires within the left cover. Phillips Screwdriver Easy
5 Place inverter and trigger back into left cover. Hands Easy
6 Connect the directional lever to the motor. Hands Moderate
7 Place right cover over the drill. Hands Easy
8 Place 9 screws into Left cover and connected left and right cover. Phillips Screwdriver Easy



After Assembly


How It Works

After disassembling the product, the function of each part, as well as how the overall product operated, was accessed.

This drill has a universal motor. It runs off of an alternating current (AC) power supply, which comes from an outlet. The motor contains a rotor that has copper wire wrapped around it. The copper wire is used to create a magnetic field. As the AC power is supplied to the rotor, it creates a magnet. The rotor is also surrounded by another magnet with the north pole of the rotor’s magnet attached to the south of the additional magnet. According to the magnetic theory, the opposite poles of each magnet attract each other, while the like poles repel each other. With this relationship, the two magnets begin to repel each other, which cause the rotor to turn. The motor is also made up of small pieces of metal called “brushes”. These brushes rub against a disk that’s attached to the shaft. When the AC power is supplied to the motor and the rotor turns due to the magnetic forces, the brushes transfer electricity to the shaft, which causes it to turn. As the shaft rotates, it causes the gears to turn as well, which then makes the chuck rotate. As the user applies force to the drill and the chuck rotates, the screw enters the targeted material. There is a cooling fan attached to the shaft that helps keep the motor from overheating. It also rotates as the shaft rotates. After reassembling the drill, it ran the same as it did before the disassembly.


Product Analysis



Note To The Reader: The purpose of this product analysis is to walk you through the engineering thought process while solving the analytical problem noted below.




Problem Statement: Calculate the max torque of the Black and Decker DR202 gear system.

Gear System Free Body Diagram
Fbd1231.JPG
Fbd2345.JPG













Please Note: positive X is to the left, positive Y points up, and a positive moment is counter clockwise.

Assumptions:
Motor will provide an initial torque (Represented by "m" on the FBD)
Gears in the gear system are different sizes
Motor is capable of providing a torque that turns the gear
Gears don't slip while rotating
The motors torque doesn't vary with time
All surfaces are frictionless


Governing Equations:
(Sum of the systems angular moment)01 +(Sum system angular impulse)0(1-2) =(Sum system angular momentum)02
Moment of Inertia: I=m*r*r
Angular Moment of Inertia: L=I*w
Torque = moment of inertia * angular acceleration

Calculations
The calculations to the gear system would require extensive understanding of many dynamics concepts and will be explained in the discussion

Solutions Check
One would verify numerical values as well as unit consistency.

Discussion
By calculating the angular moment of inertia and angular acceleration "w" of each gear one could then sum the torques of gear system in a piecewise manner. The sum of the torques would be the final output torque of the systems. Torques rotating counter clock wise would be considered positive while torques rotating clock wise would be considered negative. By varying the gear ratios and the initial torque of the motor one could vary the output torque of the system. The assumptions make sense when calculating the max torque of the system. One benefit of this system is that it can be adapted to calculate the torque as a function of time; the motor torque varies. In order to calculate the torque at a given time the motors torque would have to be illustrated by a function M(t). This function would be non-linear in nature due to the exponential increase in the motor torque over time; Until the max moment is reached. By carefully analyzing and optimizing the system above a new max torque could be created.

Ergonomic Analysis


By testing the user interaction with the product, concepts such as center of balance and user comfort can be tested. With the use of a working prototype the analysis can take place. Issues such as grip comfort and handling of the drill can be addressed.

Disassembly/Assembly Discussion

The disassembly and assembly procedures were the reverse of each other. The disassembly process was very easy and only required the use of a flat head screw driver and our hand. Once we had opened the casing the process was very easy because the housing of the drill was the only component holding the parts in place besides 2 screws on the inside. The assembly process was more time consuming due to the fact that each part had to be put back together in working order, which with the aligning the gear system, the process was somewhat tedious. The same tools were used in both the disassembly and reassembly process. The drill is back together in working order, same as when we received it prior to disassembly.

Recommended Design Changes

The drill has a few small weakness in its design. With the following recommended design changes, the product will be more appealing to the user:

1. Directional Changer - The directional changer was very large and awkward to use. With a simple button or small sliding mechanism, the directional changer would be much easier to use.

2. Screws - Black and Decker uses two different types of screws that both contain hexagonal screw heads. With the use of phillips or flat-head screws, repairs and disassembly would be much easier. Also, eliminating the the different screws and replacing them with a uniform design would be more cost effective for Black and Decker.

3. Cord - A battery operating drill is a more practical design choice. The cord seems to just get in the way and a battery operated drill does not limit the use of where the drill can be used.

4. Drill bit - The bit that is included with the drill is a very basic design. The use of a magnetic bit, or a bit with a sleeve over it would be more user friendly.

References


Black And Decker. (2007) . Instruction Manual for Models DR202 Power Drill.. Retrieved November 7, 2007, from the World Wide Web: http://www.blackanddecker.com
Power Drill. (2007) . Power Drill Principles. Retrieved November 13, 2007, from the World Wide Web: http://home.howstuffworks.com/power-drill.htm
How Gear Ratios Work. (2007) . How Gear Ratios Work. Retrieved November 15, 2007, from the World Wide Web: http://science.howstuffworks.com/gear-ratio4.htm
How Electric Motors Work. (2007) . How Electric Motors Work. Retrieved November 15, 2007, from the World Wide Web: http://electronics.howstuffworks.com/motor1.htm
Hibbeler, R. C. (2006). Engineering Mechanics Statics and Dynamics (11th ed.). St. Louis, MO: Prentice Hall.