160 likes | 611 Views
Vibratory Bowl Feeders. Heath Whittier October 11, 2010. Part Feeders. “Part feeders are machines that orient parts so that robots or other automated processes can capture and use or package the parts or components” Four Main Types: Bowl feeders : Most common type. Bowl with a
E N D
Vibratory Bowl Feeders Heath Whittier October 11, 2010
Part Feeders “Part feeders are machines that orient parts so that robots or other automated processes can capture and use or package the parts or components” Four Main Types: • Bowl feeders: Most common type. Bowl with a spiral track inside that feeds up using vibration. • Linear feeders: Horizontal conveying of components. (conveyor, carpet feeder)
Part Feeder types continued… • Centrifugal feeders (or rotary feeders): Use a bowl that spins and forces parts to the outside of the bowl. At the outside edge of the bowl, the parts are channeled into receivers when the parts are in the right orientation. Usually faster and less noisy than vibratory feeders. • Step feeders: The component parts are collected from the hopper by elevating plates, pre-sorted and fed until they reach the desired transfer height.
Vibratory Bowl Feeders “A vibratory feeder consists of a parts-orienting bowl mounted on a vibrating drive unit with a variable-amplitude controller. The drive unit vibrates the bowl causing parts in the bowl to move around a track that has been tooled to sort and orient the parts in accordance with a customer's requirements.”
Types of Bowls Cylindrical: (smaller parts, continuous feed) Conical: (heavier or sharp edge components) Stepped: (Larger components)
Bowl Feeder Videos • http://www.youtube.com/watch?v=6W8ie3ra74k&NR=1&feature=fvwp (cap orientation) • http://www.youtube.com/watch?v=CGdWKPXbJZI (speed) • http://www.youtube.com/watch?v=xxplxvm1ViM&feature=related (several types) • http://www.youtube.com/watch?v=eOIHyp8-g80&feature=related (trap) • http://www.youtube.com/watch?v=smf0B9fIoDI&feature=related (inline feeder)
Vendors • Feeding Concepts, Inc. • Fortville Feeders, Inc. • Elscint Automation • Vibromatic (since 1956) • Automation Devices, Inc. • Delta Industrial Services • Parts Feeders Inc. • Unite Automation • Jerhen Industries, Inc. • Orientech
Pricing (Prices from Parts feeders Inc.) What variables do you identify?
Limitations and Rules • Depends largely on the components and the natural frequency of the system • Because of this, bowls must be specific to task which increases time to implement and price • Limitless specifications and applications because they are so often custom made for the job
CapabilitiesBowls can come Standard or custom made Features - Standard and Optional • Fan rail, knife rail, and outside tooled designs • Precision adjustment of feed rails • Complete line of standard bowls, from 4"Ø to 48"Ø • Available in configurations for non-traditional parts • Custom tooling for sorting and part orientation • Shuttle escapements for sorting parts during orientation • Photo optic sensors • Assembly capability • 304 stainless construction • Interfaced, variable speed drive system Bowl Feeder functions • Fan Rail Design • Standard Parts and Long Parts • Stainless Steel Construction • Straight Wall Design • 4 Inch - 48 Inch Diameter • Dual Coil Drive • Multi-Lane Discharges • Assembly Feeders • Knife Rail Design • Fine Adjustment Between Feeder Rails • For Precision Parts • Clockwise orCounterclockwise Rotation • Simplicity in Setup • Solid State Control • Custom Tooled
Trap Design for Vibratory Bowl Feeders The International Journal of Robotics Research 2001 20: 891Robert-Paul Berretty, Ken Goldberg, Mark H. Overmars and A. Frank van derStappen Abstract The vibratory bowl feeder is the oldest and still most common approach to the automated feeding (orienting) of industrial parts. In this paper, the authors consider a class of vibratory bowl filters that can be described by removing polygonal sections from the track; this class of filters is referred to as traps. For an n-sided polygonal part and an m-sided polygonal trap, an O(n2m log n) algorithm is given to decide whether the part in a specific orientation will safely move across the trap or will fall through the trap and thus be filtered out. For an n-sided convex polygonal part and m-sided convex polygonal trap, this bound is improved to O((n+m) log n). Furthermore, the authors show how to design various trap shapes, ranging from simple traps to general polygons, which will filter out all but one of the different stable orientations of a given part. Although the runtimes of the design algorithms are exponential in the number of trap parameters, many industrial part feeders use few-parameter traps (balconies, canyons, slots); in these cases, the running times of the algorithms range from linear to low-degree polynomial.
Study on Vibratory Feeders: Calculation of Natural Frequency of Bowl-Type Vibratory Feeders Journal of Mechanical Design This paper treats a method of calculating natural frequency of vibratory feeders. In a bowl-type feeder, the deformation of the spring is complicated and the exact calculation of its constant is difficult. Therefore an approximate calculation is presented under some assumptions. The relations between spring constant and spring setting condition are clarified and shown in various diagrams. The equations of natural frequency for the fixed type and the semi-floating type feeder are represented briefly. The vibration direction of bowl-type feeder is also discussed. The theoretical results are confirmed by experimental studies.
Problems • Vibration/Natural Frequency – System Dynamics • Aligning parts in the correct orientation • Slow feed rates • Vibration causes a lot of noise • High power consumption, overheat • Parts bouncing around may harm them • Re-tuning often required *If the pulse and the frequency don’t match, all these problems can occur
Class activity • Design tooling for a box with a round hole in one side • You want the hole side to feed out of the bowl feeder first
References • http://www.changeover.com/feeder.html • http://www.elscintautomation.com/ • http://www.globalspec.com/LearnMore/Material_Handling_Packaging_Equipment/Material_Handling_Equipment/Parts_Feeders • http://en.wikipedia.org/wiki/Bowl_feeder • http://www.uniteautomation.co.uk/ • http://www.rnaautomation.com/downloads/VT-BA-SRC63_100-GB.pdf • http://www.jerhen.com/feedbowls.htm • http://www.vibratoryfeeders.com/bowls.htm • http://www.youtube.com/watch?v=6W8ie3ra74k&NR=1&feature=fvwp