Electrophotographic Cascade Development Test Rig Detailed Design Review

Electrophotographic Cascade Development Test Rig Detailed Design Review November 18 th, 2014 Dalton Mead Michael Warren Thomas Wossner Bridget Kearney Ruishi Shen Zachary Foggetti

Brief Background Electrophotography - How a laser printer works

What are we looking for today? ● Discuss any risks we may not have thought about ● Thoughts from new points of view ● Initial reaction on the viability of what we are proposing

Outline ● Process Flow Diagram ● Designs for Each Subsystem: ● Hopper ● Transfer Surface ● Development Zone ● Angle Adjustment System ● Recirculation System ● Lab. VIEW Program Outline ● Flow Down Diagrams ● Budget Considerations ● Project Plan ● What We’ve Learned

Process Flow Diagram

Storage System “Hopper” Function ❖ Store particles before test ❖ Capture particles being recirculated ❖ Control Mass Flow Rate ➢automated (replace below with assembly of hopper)

Connection to Transfer Surface Vertical Pivot Mount ❖ Calculated at COM of Hopper ➢Will always hang vertical due to COM ❖ Allows flexibility of angle for experiment ❖ 1/4” diameter will be strong enough

Hopper Connection Exploded Concept

Mass Flow Rate Control ❖ Linear Actuator ❖ Slide open door at bottom of Hopper ❖ Only needed to push/pull 3. 8 N of force ❖ Still waiting on quote (similar cost between $200 -$450) ❖ Mounted on side of Hopper ❖ Controlled by Labview UI http: //www. physikinstrumente. com/product-detail-page/m-272 -1000650. html

Next Steps ❖ Work with Recirculation for correct transfer system ❖ Design Motor Mount System ❖ Finalize linear actuator choice ➢waiting on companies response

Risks of Hopper ID Risk Item Effect Failure Mode 1 Toner leaks loss of initial through the toner onto Non sealed door dev. zone door 2 Motor is a little pricey, haven’t got More quote yet Searching Exceed budget Likelihood 1 1 Severity 2 2 Action to Importance Minimize Risk Owner 2 Add malleable material to seal edges, material that the particles won’t stick to Dalton 2 Proper shopping and calling companies Dalton

Bill of Materials ❖ 4”x 12” square aluminum tube ❖ 1/4”-1/2” Inner Dia. Bearing ❖ 1/4”-1/2” Aluminum Rod (matches bearing I. D. ) ❖ 1/4” aluminum plate (stirrup, door, motor casing) ❖ Linear Actuator

Transfer Surface

Transfer Surface ❖ Inspired by a panini grill ❖ Opens completely for user to expose the face of each surface ➢ Allows for easy access of removable development zone ❖ Inhibits movement of plates, relative to each other

Development Zone ❖ Two surfaces in parallel ❖ 3 in. x 0. 12 in. aluminum plates surrounded by ¼ in. of insulating material inserted on the plastic transfer surface ❖ Polarity of both plates can be changed to positive or negative ❖ Electrical field between the two plates allows electrophotography to take place ❖ Charging both plates will allow for experimentation with the separation of toner from the carrier beads

Removable Aluminum Insert ❖ Plates will be easily removable for inspection of test results ❖ Aluminum plate will act as a removeable insert ❖ Insert will be pressed flush to the transfer surface using a spring contactor tab ❖ Spring tab will have two functions ➢ Press insert flush to transfer surface ➢ Transfer electric charge to the aluminum insert

Parallel Spacing Between Plates ❖ Space must be big enough for both toner particles and carrier beads to flow through freely ❖ According to the field intensity formula, E=v/d ➢ If the space is too small, the carrier beads may begin to develop ➢ If the space is too large, the toner particles may not develop at all ❖ A plate gap of approximately 2 mm is desired to begin testing toner particles with 90μm ❖ Gap will be adjusted by means of motor automation and use of adjustable, parallel shims mounted on theleft and right sides of each plate http: //www. regentsprep. org

Parallel Spacing Between Plates ❖ Adjustable, steel, parallel shims ❖ Easily expand contract to desired size in opening ❖ Exact size can be set with micrometer ❖ Lock desired size by set screws ❖ Range in height from ⅜ in. to 2. 25 in. ❖ ¼ in. thick ❖ Range in length from 1. 77 in to 7. 5 in, ❖ Available for purchase online from Little Machine Shop

Automation of Plate Spacing ❖ Automate spacing between parallel plates using a 12 V DC linear actuator ❖ Motor is mounted to the top surface of the top plate and connects to the parallel shims via metal brackets ❖ Vertical gap distance required for adjustment is approximately 2 mm (<. 1 in. ) ❖ Adjustable Parallel sets have a slope of approx. ⅕, so minimum stroke required is about. 5 in. PA-02 -2 -200 LINEAR ACTUATOR (STROKE SIZE 2", FORCE 200 LBS, SPEED 0. 94"/SEC) STROKE: 2 INCH FORCE: 200 LBS SPEED: 0. 94"/SEC

Risks of Development Zone and Transfer Surface ID Risk Item Effect Action to Failure Likelihoo Importan Minimize Mode d Severity ce Risk Shock injury, damage to device, exhaust hood or Misuse of power nearby equipment source 1 Voltage arching between the two parallel plates 2 Buildup of Alumnium plates not toner particles flush to on edges plastic 3 Developme Motor nt zone not Failure of malfunction set motors to s correctly work Spring contactor tab loosens Owner 2 3 3 Practice caution when using the device at all times Bridget 1 3 3 Bridget 2 3 2 Bridget

Development Zone and Transfer Surface BOM ❖ ❖ ❖ ❖ 2 Aluminum plates (3 in. X 0. 12 in. ) Insulating material Parallel “shims” (varying in size) Plastic Surface 12 V DC Linear Actuator Hinge Materials Spring Contactor Tab

Angle Control System Chosen method: Motorized rack/pinion arm

Reasoning ❖ Rack rests on ground surface -- prevents slipping ❖ Low torque required to hold position ❖ Stepper motors inexpensive

Requirements ❖ Must be able to generate enough torque to hold position or raise transfer surface angle (est: 11 Nm for hold) ❖ Gear teeth must not slip ❖ Should minimize space necessary under transfer surface ❖ Lift arm must bear some load

Design Process

Design Process Assumptions: m. S = 15 kg m. A = 1 kg d 1 = 4” d 2 = 9 ” d 3 = 2 ” d 4 = 3 ” r = 0. 75” 45° ≤ Θ ≤ 80° This leads to a holding torque of appr. 10. 28 Nm

Feasibility Technical: - Motors with the required power exist - Motor heat should not be a problem Fabrication: - Motors with estimated torque are available - Simple rack/pinion setups are also available

Potential Part Solutions ❖ Motor: Kollmorgen KM series ❖ Rack/pinion gearing: Mc. Master-Carr ❖ Lift arm: machined aluminum (stock from Mc. Master-Carr)

Angle Adjustment Risks Risk ID # Risk Item Risk Category Effect Failure Mode L S I Action to Minimize Owner 1 Pinion gear cannot support load Product risk Angle adjustment / holding becomes impossible Design failure 1 3 3 Ensure proper gears are selected Mike 2 Lift arm deforms under load Product risk Angle adjustments become inaccurate / impossible Design failure 1 3 3 Ensure materials properties and geometry are appropriate Mike 3 Motor has insufficient power Product risk Raising / maintaining angle becomes impossible Design failure 1 3 3 Ensure motor to be purchased is sufficiently powerful Mike 4 Purchase parts are too expensive Project risk Project goes over budget Logistics failure 2 2 4 Ensure that all parts to be purchased are affordable All

Angle Adjustment - Next Steps ❖ Determine prices for potential purchase parts ❖ Determine mass properties of design’s components ❖ Determine motor torque required

Recirculation System 2 Components: ❖ Screw Conveyor (Primary) ❖ Manual (Secondary)

Why Both Systems? ❖Screw system is a lofty goal ❖Manual system provides reliable backup ❖At very steep angles (>70 degrees), screw becomes unreliable

Needs Screw Conveyor: -Needs to move 1. 3 L/min of toner at a 70 degree slope -Must not strip particles of charge → must be insulative -Must not be so large that it interferes with testing Manual System (Bucket): -Must maximize the run time before recirculation is required (>1 min) -Must not strip particles of charge → must be insulative -Must not be so large that it interferes with testing -Must prevent particle overflow

Well that sounds nice, but this screw thing is hard to visualize. . . http: //www. youtube. com/watch? v=_OZv 2 kf_SCs (1: 43)

Optimal Screw Conveyor Design - An Overview - “The Turn of the Screw: Optimal Design of an Archimedes Screw” by Chris Rorres (Journal of Hydraulic Engineering, Jan. 2000) - Based on outer dimensions (screw radius, slope, length), optimal inner dimensions (shaft radius, pitch, # of blades) can be calculated

Optimal Screw Conveyor Design - An Overview

Screw Conveyor Design Dimensions Set by Us: L=Length of Screw: 20’’ �� =Angle between centerline & edge of screw (must be greater than slope of conveyor): 70 o Ro=Radius of Screw: 1. 4’’ Calculated Optimal Dimensions Ri=Radius of Shaft: 0. 75’’ # of Blades: 3 Pitch: 2. 17’’

Design Feasibility - Screw Fabricate-ability For the sizes we will need: -Can buy solid PVC rods (Mc. Master-Carr, ~$80) -Can machine into auger/screw shape (acc. to Rob Kraynik in the ME machine shop) -Can buy PVC pipe from any hardware store (i. e. Lowes, ~$6) -Can buy small DC motor (Mc. Master-Carr) Technical Feasibility -Similar systems commonly used to move powder, water -At 70 degree slope, benchmark particle movement rate of 1. 3 L/min is achieved @ 71 RPM

Manual Design Internal Dimensions: h=Height: 6’’ w=Width: 4’’ d=Depth: 4’’ t=Material Thickness: 1/8’’ Volume = hwd = 96 in 3 = 1. 6 L -Slightly larger than hopper -Ensures no overflow

Design Feasibility - Bucket Fabricate-ability -It’s a bucket, so not difficult Technical Feasibility -Volume of 1. 6 L is slightly larger than hopper, preventing overflow -At benchmark flow rate of 1. 3 L/min, recirculation interval is ~1 min 20 sec

Recirculation System Risks

Next Steps for Recirculation System ❖ Continue POC for screw conveyor ❖ Decide on motor to turn screw ❖ Finalize BOM, costs ❖ Interfacing/connections with hopper, transfer surface

Lab. VIEW Program Outline

Requirements Flow Down Diagram 1

Requirements Flow Down Diagram 2

Budget Estimation - HOQ Phase II

Budget Estimation - Results from HOQ

Project Plan - Budget and BOM

Project Plan- Sketches & RFD Diagram

Project Plan- Test Plan & Assy Process

What We’ve Learned ● Be braced for changes in CRs ● Thorough project plans are beneficial ● High-level system requirements are easily neglected when working at the subsystem level

Summary ● Process Flow Diagram ● Designs for Each Subsystem: ● Hopper ● Transfer Surface ● Development Zone ● Angle Adjustment System ● Recirculation System ● Lab. VIEW Program Outline ● Flow Down Diagrams ● Budget Considerations ● Project Plan ● What We’ve Learned

Questions?