CORP1 BUDWEISER CHIP PULLER REDESIGN Auburn University College
CORP_1 BUDWEISER CHIP PULLER REDESIGN Auburn University College of Mechanical Engineering Senior Design Project March 23, 2006
Team Members § John Braswell § Dan Culpepper § Ben Davis § Mark De. Ramus § Patrick Gilley § Mitch Swinson § Calvin Winston
Current Problems § Unit is extremely heavy, too large and complicated § Cable does not last and gets jammed § Clamp that connects to torpedo is unreliable § Clutch failures. § Hydraulically driven § No speed control and lacks the proper strength § Radio system is unreliable and has no indication
Specifications and Constraints § Durable design § Simplified design § Elimination of Hydraulics § Work with existing equipment § Shorten time required to pull chips § Cable/Winch system must be • Clean of yeast during retraction • Spool must be contained for safety • Torque must be adjustable and tamper proof § Improve Operator interface • E-stop • Vary retraction speed
OUR VISION
The Setup - Enclosure § Size – 53 in tall, 24 in wide, 22 in deep § Arm attaches to torpedo • Holds wash-down and cable • Provides stability and safety! § Cable and spool completely contained for cleaning
The Setup - Drivetrain § AC variable frequency drive § AC Motor – 5 HP w/ piggyback blower § Belt Speed Reduction § Electric Clutch § Spool w/ level wind system
How does it work? § Operator transmits radio signal to the drive § VFD turns motor at speed specified by operator § Belt system reduces motor speed at spool to 150300 fpm § Torque transmitted through clutch to the cable spool, winding in the cable
Why a variable frequency drive? (VFD) § $1, 200 § Built in basic programmable logic § Combines almost entire electrical system into one small box (5 in x 10 in x 7 in) § On-board digital and analog inputs and outputs § Motor speed accurate within 1/10% of drive output
Why a 5 HP Motor w/ blower? § Provides 550 lbf at spool, only require 350 lbf • Excess allows for losses through the system • Future circumstances may require more pulling power • Cost effective – $2, 906 • 8 pole - 1000: 1 constant torque § Piggyback blower • Cools motor • Allows motor to turn at low speeds • Extends life § Laminated Steel Frame • Able to withstand top-down light wash down
Speed Reduction § A-Section V-belt § Diene-based rubber with polyester reinforcing cords § Durable, Flexible, able to absorb heat § Shock Absorption characteristics § Fatigue life known § Easy replacement § Cheap ($5 -$10 each) § Cast Iron Bushing Bore Pulley § Cost ($30 -$50) § Belt Speed Reduction § Electric Clutch § Spool
Advantages of New Design § Much less complicated! • Only five main components o VFD, Motor, Belt reduction, Electric Clutch, Spool • Eliminates hydraulic system, no contamination issues • Electrical system is almost entirely contained by VFD • Easier to maintain § Smaller – designed under 53 in tall, 22 in deep, 24 in wide!
Advantages of New Design § Able to position machine BEHIND torpedo or U-Tub • Straight pull to rake • Cuts down on cable frays/snags § Lighter ~750 lbs § Spool w/ Level Wind System
CLUTCH
Clutch Selection § Concerns § Clutch disengage point § Max Torque capability of clutch § Operating speed § Reliability
Why an electric clutch? § Allows remote and local E-Stop capabilities § Instant response § Provides free-wheel capability with negligible resistance. § When disengaged, only inertia transmitted to the operator is from the cable spool. SAFE!
Possible Clutch Selection § Overload Release Clutch from Boston Gear made by Centric Clutches § Looking at ORC 3 SA C M clutch type § Mechanically operated clutch with variable cutoff torque § Max Torque of 2200 lb*in § Max RPM 1200 § Max dimensions 5. 87 inches thick 8 inch diameter
SPOOL & GUIDE
Cable Spool § 8 -12 inch barrel diameter § 6 -8 inch traverse width § Stainless steel Construction § Level-Wind System § 1000 lbs pull § 7/32’’ nylon coated cable § $1000 -$1500 cost § Shipment time: 3 -4 weeks
Level-Wind System § Geared to Spool § Neatly wraps wire on spool § Guide has roller bearings
Examples
CABLE
Mechanical Cable § Primary consideration • Durability o o Breaking strength q Diameter q Cable construction q Coating types Reducing Friction q Coating types
Strength Considerations § Cable Material Options • Stainless Steel • Titanium § Cable Construction • 7 x 19 • Types of Core o SWC o IWRC
Coating Consideration § Purpose of coating determines • Manner of application o Liquids, powders, laminates, etc. • Dispensing (application) technique o Brushes, roller, and most common sprayer • Qualified material options o Nylon o Teflon
Additional Considerations § Line of sight § High friction areas § Spool Size § Lead Time • 4 -5 Weeks
ELECTRICAL
Electrical Systems § The electrical system has three primary objectives: • Safety!!!!!! • Power Supply to the system • Logic
Safety § Safety is accomplished by a series of Sensors and Relays § Information from these is fed into a Programmable Logic Controller (PLC)
Safety Concerns § Inside Operator • Emergency Stop • Time Delay/Ramping • Variable Speed • Machine Operation Indicator • Disable reverse feature on drive
Safety Concerns (cont. ) § Clamp/Latch Considerations • Contact Relay § Outside Operator • Door Proximity Switches • Sense Stall Conditions o Cut-Off Torque o Spool malfunction
Power Delivery § 480 V Delivered to Drive § 460 V Power Delivered to motor § Step down Voltage from 480 V Source o Radio o PLC o Various Sensors
Power Supply § Logic Outline • Verify all safety conditions met • Drive starts motor • Safety conditions continuously checked • Drive stops motor o Safety condition not met o Stop command issued
Electrical Cost & Lead Times § Costs • PLC $400 • Proximity Switches (3) $420 • Motion Sensor $200 • Misc. Wiring/Enclosure/Fixtures $600 Total § Lead Time • Approx. two weeks $1620
RADIO AND CLAMP
Radio and Clamp § Clamp is all in one design § Locks onto Torpedo securely § Radio • GTA said that correcting this problem complex • Professor believed a hard wire is best chance • Company offering a preliminary unit at approx. $2500 • Retired Professor believes there may be multiple options to look at
ECONOMIC ANALYSIS
Ballpark Economic Analysis
Approximate Lead Times § AC Motor/Drive 6 weeks § Speed Reduction 2 weeks § Clutch 2 weeks § Spool/Guide System 4 weeks § Electrical Components 2 weeks § Stainless Steel 2 weeks § Cable 5 weeks § Machine Construction 3 weeks
Issues with Current Puller Design ü Too complicated - too many parts. ü Cable frays and jams the puller. Cable coating prematurely fails. ü Cable is difficult to retract from the puller into the chip tank. ü Torpedo clamp cable guide fails frequently. ü Clutch failures. ü Chip puller is very heavy. ü Puller enclosure too large to allow alignment of torpedo / puller in aisle. ü Chip puller is hydraulically driven. ü Puller does not pull hard enough - loses pull calibration - takes off very quickly when activated – has only one speed. ü Operator remote control requires taking one hand off of chip rake to activate. § Remote control requires two clicks to start and one to stop. There is no indication if control worked.
QUESTIONS?
- Slides: 41