Agenda• Introduction 12:00

• Ozone Fan/Filter Assembly 12:15• Monitoring Charge on Photoconductor 12:30• LED Exposure System 12:45• Paper Delivery System 1:00• High Visibility Warning Signs 1:15• Camera System 1:30• Transfer Roller Speed Measurement 1:45• Labview Control Interface 2:00• Additional Issues 2:15

Detailed Design Review

P09503 – Electrophotographic Development and Transfer Station

Friday, October 31, 200812:00PM-3:00PM

76-A120

Team MembersName Discipline Role Email

David Schwartz ISE Team Lead – Warning Signs drs8889@rit.edu

Ruth Gay ME Paper Delivery System rip4474@rit.edu

Phillip Lopez ME Ozone Filter pml6464@rit.edu

Dan Summers ME ME Support dcs5083@rit.edu

Rachel Chrash EE LED Exposure System rec0678@rit.edu

Min-Shi Hsiao EE PC Voltage Measurement mxh7790@rit.edu

Andrew Kearns EE Transfer Drum Speed Measurement, Camera System

amk0477@rit.edu

Sasha Oliver CE User Interface aas1878@rit.edu

Introduction to Electrophotography

• Electrophotography is base technology used in modern day copy printers

• Six Step Process– Charging– Exposure– Development– Transfer– Fusing – Cleaning

• EDTS only includes first four

Project Introduction

• EDTS will contribute to understanding of current EP technology– Manipulation of input parameters

• Objective is to take existing EDTS and– Make it functional– Improve Usability– Automate Control of Machine– Additional Performance Improvements

Project Deliverables

• 1 – An inventory and status of current sub-systems, including needed support systems.

• 2 – A working EDTS.• 3 – Demonstrably improved device safety.• 4 – An improved user interface (includes control and

display functions)• 5 – Device documented for use, maintenance and

upgrade of the device (User & Lab Technician Manual)• 6 – Demonstrably Improved Sensing and Control

Subsystem

System Level Overview• Photoconductor

– Hold Photosensitive Material

– Photosensitive Material• Increased conductivity

during exposure to light– Traverse EDTS– Interact Photosensitive

Material with• Charge• Discharge• Development• Transfer

System Level Overview

• Charging– Establish an electrical

field within the area of the Photoconductor

– Photoconductor passes at very small distance

– Corona• Wires subjected to up to

10,000 Volts– Grid

• Distribute charge of corona

System Level Overview

• Exposure– Expose Photosensitive

material to light– Reduce charge on

exposed areas– Electrostatic latent

image remains

System Level Overview

• Development– Deposit charged toner

particles onto charged areas of photosensitive material

– Magnetic Developer creates a “wall” of toner and developer

System Level Overview

• Transfer– Transfer toner from

photosensitive material to paper

– Transfer Drum is Charged

– Two Steps• Toner to Transfer Drum• Transfer Drum to Paper

System Level Functional Diagram

•Functional Diagram shows areas for improvement

Customer Needs• 1. Is Operational • 2. Is Safe • 3. Minimizes user intervention during Charging • 4. Minimizes user intervention during Discharge • 5. Minimizes user intervention during Development • 6. Minimizes user intervention during Transfer • 7. Minimizes user intervention during maintenance • 8. Can monitor key process parameters • 9. Automation of Parameter Settings • 10. Can operate and monitor machine from one

interface • 11. Easy to learn to use • 12. Areas for system upgrades are identified and

documentation for upgrade procedures available where applicable

• 13. Maintenance of system is documented • 14. Both drawings and Bills of Materials document

device • 15. Operation of Device Is Documented

• 16. Toner clean up • 17. Inventory and Status Report of current systems • 18. Vary charging voltage• 19. Vary charging current • 20. Vary exposure • 21. Can accommodate different toner materials • 22. Vary development voltage • 23. Vary development current • 24. Can use multiple toner stations • 25. Vary transfer voltage • 26. Vary transfer current• 27. Improve exposure subsystem • 28. Monitor charge of the Photoconductor • 29. Incorporate other manufacturers development

systems • 30. Paper delivery system Ability to accommodate

different types of media

Engineering Specifications

• Please see documentation

Ozone Fan/Filter Assembly

Phil Lopez

Description• Reduce and Secure Ozone Test Stand

– Ozone hazardous to humans if exposed to enough– Law states maximum ozone in A/C Space is 0.05 ppm

[1]– >0.200 ppm increases risk of health issues [1]

• Two Options– Verify current system or – Implementation of further improvement to control

Ozone Levels

[1] http://www.ozoneservices.com/articles/007.htm

Ozone Customer Needs Satisfied and Associated Specifications

Customer Need Satisfied

Specification Ideal Value Marginal Value

Is Safe Amount of Ozone Present in Air

0.001ppm 0.050ppm

Maintenance of System is Documented

Number of screws needed to detach ozone filter for removal and cleaning

4 4

Current System

Current Mount

New Mount (If Necessary)

Proof of Concept

• Measure ozone at various locations to determine if measurements are within limits

• Test/Experimental – TBD due to insufficient equipment

= Test Areas

Proof of Concept

Proof of Concept

• Set values– 0-1.0 kV at increments of 0.1 kV for Grid and

Corona– 1-10kV at increments of 0.5 kV for Grid and

Corona• Will Measure

– Ozone Produced without Fan– Ozone Produced with Fan

• At original height and two inches higher

Proof of Concept

• Material Selected Al 2024• Stress found to be ~520 psi• Less than Yield Stress of 45ksi• Less than Ultimate Stress of 65ksi

Bill of MaterialsItem Price Lead Time Supplier

Sheet of Al 2024 $97 Available McMaster

Risk AssessmentDescription of

RiskPossible

ConsequencesProbability of Risk (H/M/L)

Severity of Risk (H/M/L)

Overall Risk (H/M/L)

Contingency Plan

Loose Fan Ozone over EPA regulations

M H M Reattach

Particulate Build Up or Clogging

Ozone over EPA regulations

M H M Examine and do required maintenance

Power Loss to Fan

Ozone over EPA regulations

M H L N/A

Ozone Measurement Device

Unable to measure Ozone levels

L H M Not Available

Monitoring the Charge on Photoconductor

Min-Shi Hsiao

Description• Output quality determined by functionality of

each subsystem• Monitoring charge of photosensitive material will

help characterize exposure input noise source• Can also help create charge v. exposure plot after

measurement• Measuring device is Trek 344 Electrostatic Volt

Meter (ESVM)• Probe functions like capacitor that charges up to

same level as object being measured

Customer Needs Satisfied and Associated Specifications

Customer Need Satisfied

Specification Ideal Value Marginal Value

1.20: Monitor key process parameter

Charge on photoconductor after charging

same as the applied voltage

+/- 10% of the ideal value

Charge on photoconductor after discharge (exposure)

Proportional to the exposure level

+/- 10% of the ideal value

1.70: Monitor charge of the Photoconductor

Measurement resolution

2.5 dpi +/- 0.254

Drawings/Schematics

• Probe must be placed 2mm from PC surface• Cannot be held by hand

– Could result in short or shock

• Position should be fixed during measurement• Existing Camera Mounts used

– Allows for easy adjustment– Intermediate probe mount needed to attach

probe to camera mount

Probe

Current Camera Mounts

Intermediate Mount

Current Camera Mount with Probe Fixture

Location of Measurements

Proof of Concept

• Mylar used for testing instead of PC Material– Mylar not sensitive to light, no exposure

necessary

• Mylar glued to PC plate and driven down EDTS• Begin with 500 Volts at charging• Measurements taken after charging and

exposure

Risk AssessmentDescription of

Risk Possible

Consequences Probability of Risk (H/M/L)

Severity of Risk (H/M/L)

Overall Risk (H/M/L)

Contingency Plan

Manually moving the brick

Electric shock L H L Avoid contact when machine is powered, user manual, warning sign, wear insulating gloves

LED Exposure System

Rachel Chrash

Description

• LED Print Heads used in copiers and printers to expose Photosensitive Material are commonly used

• LED Exposure system to replace current incandescent system

• Advantages– More versatile and reliable light source– Low Power Consumption– Longer Bulb Life– No potential for overheat– Inexpensive to replace

Customer Needs Satisfied and Associated Specifications

Customer Need Satisfied

Specification Ideal Value Marginal Value

3.2: Improve exposure subsystem

Ratio of Intensities 1 <100

Current System vs. LED System

• Current System– Incandescent light uses

collimating lens to collect light and direct toward image plane

• LED System– Provide more direct

source of light to image plane

incandescentlight source

collimatinglens

image planewith modulating masks

image planewith modulating masks

4x4 array of LEDs

Current System Better LED system

incandescentlight source

collimatinglens

image planewith modulating masks

image planewith modulating masks

4x4 array of LEDs

Current System Better LED system

LED Array

Relative Intensity vs. Wavelength• Plot shows intensity, or

relative spectral power distribution w.r.t. wavelenth

• PC Material most sensitive to blue light which has shortest wavelength

• Explains why system can be successfully operated in yellow light without large impact on PC exposure

Proof of Concept• Most successful exposure results in even light distribution

across entire image plane• Three light sources tested using Gossen PanLUX Analog Lux

Meter• LUX = intensity (lumen/m2)• Grid constructed over image plane at level where exposure

takes place• Light intensity and uniformity measured every 1x1 inch• Pinpoint measurements were then taken of the current

system– 2x2 LED Array– 2x3 LED Array

Proof of Concept

  Intensity (Lux) Intensity Ratio

Current System 5600 NA

2x2 LED Array 100 56 <100

2x3 LED Array 145 39 < 100

Proof of Concept

Mounting System

• Array can be contained inside projector casing– Located at bottom or– Located on Small Shelf at height TBD by testing

• Larger than 3x3 array could pose issue due to size– Modify Projector Case

Bill of MaterialsItem Number

Description Model Number Qty

1 Luxeon Blue LED LXHL-BR02 4

2 4 Pin High Brightness LED 276-203 4

Risk AssessmentDescription of

RiskPossible

ConsequencesProbability of Risk (H/M/L)

Severity of Risk (H/M/L)

Overall Risk (H/M/L)

Contingency Plan

Lead Time if Parts need to be ordered

Time Delay L L L Order Ahead

Uniform Light Distribution

Uneven Exposure H H H Further LED Testing

Mounting Current LED System

Not Centered and Time

L L L Testing

Larger LED Array Doesn’t Fit Inside Projector Case

H H H Modify Projector Case

Paper Delivery System

Ruth Gay

Description

• Existing roller system requires manually catching paper after application of toner from roller

• Possible risks of manual handling– Shock Short from High Voltage Roller– Pinch Point of Rollers and Pneumatics– Marred Image Quality

• Paper Delivery System Solution– Hold 4.25” x 5.5” paper samples– Fit in available space

Customer Needs Satisfied and Associated Specifications

Customer Need Satisfied Specification Ideal Value Marginal Value

Is safeHuman Shock/Short

Faults Identified during FMEA Analysis

0 <5

Is safePinch Point Faults

Identified during FMEA Analysis

0 <2

Is safeInsufficient or Not Present Warning Labels identified

during FMEA Analysis0 <1

Minimizes user intervention during

Transfer

Human Shock/Short Faults Identified during

FMEA Analysis0 <5

Minimizes user intervention during

Transfer

Pinch Point Faults Identified during FMEA

Analysis0 <2

Minimizes user intervention during

Transfer

Insufficient or Not Present Warning Labels identified

during FMEA Analysis0 <1

Paper Delivery SystemPass standard “EP Process

Test”N/A N/A

Detailed Drawing/Schematic

Tray Drawing

Right Side Bar Drawing

Left Side Bar Drawing

Cross Bar

Support Leg (x 2)

Proof of Concept

BOMPart P/N Mat'l Specs Qty Price Package size

Socket Cap Screws

92185A991 stainless steel

5/32" hex socket, 10-32

thd, 3/4" length, fully

threaded, head: dia .32"

ht .190"

8 $8.86 25

.032" Aluminum

Sheet1651T11

6061 Aluminum

12"x12", brushed

Finish, .032" Thk

1 $12.76 1

.375" Thick Aluminum

Sheet9246K23

6061 Aluminum

12"x12", Unpolished finish, .375"

Thk

1 $31.98 1

Aluminum Rod

6750K1316061

Aluminum12" length,

1/4" dia.1 $3.41 1

Total Material Cost

        $57.01  

Risk AssessmentDescription of

RiskPossible

ConsequencesProbability of Risk (H/M/L)

Severity of Risk (H/M/L)

Overall Risk (H/M/L)

Contingency Plan

Lead time of parts

Not completed soon enough

M M M Make at in-house shop

Cost Exceed budget L M M Change part design to minimize cost, use available stock material

Implementation of High Visibility Warning Signs

David Schwartz

Description

• Purpose of warning signs– Alert user to specific hazard– Identify how hazard can be avoided

• Remove current warning signs• Replace with ISO designed signs• Add new ISO signs where needed

Customer Needs and Associated Specifications

Customer Need Satisfied

Specification Marginal Value Ideal Value

Is Safe Pinch Point Faults Identified during FMEA Analysis

<2 0

Is Safe Insufficient or Not Present Warning Labels Identified During FMEA Analysis

<1 0

Is Safe Human Shock/Short Faults Identified during FMEA Analysis

<5 0

New High Voltage Sign

Old High Voltage Sign New High Voltage Sign

Actual Height of Sign = 1.5”

Pinch Point Sign

Actual Height of Sign = 1.5”

System Warning Signs

Actual Height of Sign = 1.25’

Before and After

Before After

Proof of Concept• Signs Designed under guidance of ISO-3864

– Establishes the safety identification colors and design principles for safety signs to be used in workplaces and in public areas

• Danger - signal word used to indicate an imminently hazardous situation that, if not avoided, will result in death or serious injury– Chosen for High Voltage and Pinch Point

• Caution - signal word used to indicate a potentially hazardous situation which, if not avoided could result in minor or moderate injury– Chosen for overall system warning

Size of Signs

• ISO Equation: H = D/40– H = Height of Sign (mm)– D = safe viewing distance (mm)

• Pinch Point / Electrical Hazard– Safe Viewing Distance is 5 feet– Results in sign height of 1.5 inches

• Avoid Injury– Safe Viewing Distance of 50 feet– Results in sign height of 1.25 feet

Other Sign Details

• Signs will be placed on both sides of identified hazard areas

• Hazard Areas identified during Failure Modes Effect Analysis (FMEA)

• Signs will be placed as not to disturb operation and maintenance of machine

• Signs made from laminated paper• Signs attached using double sided tape

Risk AssessmentDescription of

RiskPossible

ConsequencesProbability of Risk (H/M/L)

Severity of Risk (H/M/L)

Overall Risk (H/M/L)

Contingency Plan

User Ignores Sign

Shock/Short or Pinch

M M M Assure the signs are the proper size

Signs Detach No sign present

L L L Attach all signs securely, print extra

Camera System

Andrew Kearns

Description

• Purpose is to gain understanding of how image is developed onto photoreceptive material

• Photoconductor system stopped • Photoreceptive material imaged after

development and before transfer• Nikon D50 Camera used to Study Process as it

occurs• Mirror will reflect image of photoconductor to

camera lens

Customer Needs and Associated Specifications

Customer Need Satisfied

Specification Ideal Value Marginal Value

Can Monitor Key Process Parameters

Take image the size of PC

9”x4.75” 7”x4”

Camera System in Machine

Proof of Concept

• Utilize one of three existing mounts• Third Magnetic Sensor will tell Labview when

to stop Photoconductor for image capture• Camera will interface with computer via USB• Labview will call command to Nikon Software

to capture image• LED Bar may be removed if paper delivery

system occupies too much space

Risk AssessmentDescription of

RiskPossible

ConsequencesProbability of Risk (H/M/L)

Severity of Risk (H/M/L)

Overall Risk (H/M/L)

Contingency Plan

Camera Space

Less space for paper delivery

H M M Use front surface mirrors to Capture a reflected image

Picture Timing

Image decay on PC

L L L Speed up PC

Mount Deterioration

Mount is unstable

M H H New Mounting System

Transfer Roller Speed Measurement

Andrew Kearns

Description

• Speed of transfer roller critical to timing control and image quality

• Need to assure that transfer drum rotates at the same speed as the moving photoconductor as to not elongate/condense the image

• Need to assure that the transfer roller will be in the proper position for transfer to paper

• Encoder provides feedback as to current speed of drum

Customer Needs Satisfied and Associated Specifications

Customer Needs Satisfied

Specifications Ideal Value Marginal Value

Can Monitor Key Process Parameters

% difference between speed of PC and Speed of Drum

0% +/- 5%

Proof of Concept

• Optical Encoder sends 1024 pulses / rev

Proof of ConceptA & B Outputs of Drum Encoder at 1.74kHz

Measurements Taken for Encoder B Output SignalVpp 2.20E+00

Frequency 1.74E+03

Period 5.74E-04

Pulse Width+ 2.82E-04

Pulse Width- 2.92E-04

Risk AssessmentDescription of

RiskPossible

ConsequencesProbability of Risk (H/M/L)

Severity of Risk (H/M/L)

Overall Risk (H/M/L)

Contingency Plan

Inability to interface with DAQ

Decreased image quality

L H M Drive a seven segment display with the encoder output

Inability to read A and M outputs

Unknown direction of motion

H M H Verify proper acquisition of signals

Labview Control Interface

Sasha Oliver

Description

• Current control system is done via KV300 PLC• Better solution needed to replace current

system with a new user friendly interface• Labview uses dataflow programming to define

inputs/outputs and execution sequence of the virtual instrument

• Connect devices directly to DAQ to allow for more robust control

Customer Needs Satisfied and Associated Specifications

Customer Need Satisfied Specification Ideal Value Marginal Value

Can monitor key process parameters

Ability to view current status of machine during operation

Yes Yes

Automation of Parameter Settings

UI Includes Automatic and Manual Control of Device

Yes Yes

Can operate and monitor machine from one interface

Ability to control system with current controls and improved controls

Yes Yes

Easy to learn to use LEEERS Usability Test Result

Extremly East to Use Easy to use

UI with Automatic Setting Enabled

UI with Manual Settings Enabled

Proof of Concept

Risk AssessmentDescription of

RiskPossible

ConsequencesProbability of Risk (H/M/L)

Severity of Risk (H/M/L)

Overall Risk (H/M/L)

Contingency Plan

Interface may not be able to control system as the PLC did

Some parts of the system may not work

M H H Refine system

The previous state machine is not replicated correctly (incorrect parameters passed into device)

Damaged parts L H M Refine State machine

Further Issues

• Tilting or Machining the Development System• Development System Toner Uniformity• Documentation of a user manual• Identification of a DAQ for purchase• Toner Bias• Test Plan with Critical Parameters Table• Transfer Roller Height Restriction• Air Filtration System