Parts Feeders

Vibratory Bowls - An Introduction

Vibratory parts feeders use an electromagnetic drive to induce movement. As the drive unit is energized, the parts will separate and work their way toward the outer wall of the bowl, and then up the inclined track in the bowl. When the parts arrive at the tooling, they either pass by it or fall back into the bowl depending upon their orientation at that point. After the parts have passed all the tooling profiles, they will be consistently oriented for delivery to the accumulation device outside of the bowl.

Making a choice of what parts feeding method is appropriate to your application is crucial to the success of an operation. The most important factor is the type of part to be fed. Bowl sizes and types are determined through a variety of factors, for example,

Part size and configuration,
Part abrasiveness,
Condition of the part when handled,
Feed rate required (parts per minute PPM required)

Selecting the Right Feeder

The diameter of the vibratory bowl should be many times the length of the part to be fed. Good feeding characteristics come primarily from part contact with the bowl track. Other factors influencing the bowl size are the spacing between the tracks (pitch), the width of the track, and the size of the return pan.

There are three basic types of bowls with additional specialty bowls used for unusual or difficult applications. All these can be mounted atop the same base drive units to accommodate a wide variety of parts.

Outside Tooled (O.T.) Bowls

These are the most common style of bowl used in applications requiring moderate-to-high feed rates, multiple lines of feed, or where intricate tooling is required to properly orient the part. The outside track portion houses all of the modular tooling needed to bring the part to its desired orientation. Parts that are correctly oriented advance to the discharge while incorrectly positioned parts fall from the track into the return pan for re-circulation.

The Outside Tooled Bowl discharge height is based on the tooling required for the desired part orientation and feed rate. O.T. Bowls can be designed with multiple lines tooled to correctly orient the part if your application requires high feed rates. Once the lines are oriented, the parts can converge back to one line of feed to produce extremely high rates.

Inside Tooled (I.T.) Bowls

These are based on the same basic straight wall core as used in the O.T. bowls. In this case, the tooling all occurs inside the bowl and is suited towards simpler parts and lower feed rates. The I.T. bowl uses a smaller drive unit due to the lack of external tooling weight, the ability to load a greater amount of parts into the bowl since there is no return pan to clog, and a quicker turnaround due to the reduced work the tooler has to do to orient the part.

Cascade Bowls

These are primarily used for simple applications having in-bowl storage requirements. The Cascade differs from the straight wall bowl because it has no internal "over and under" tracks. Cascade Bowls are used where parts could wedge between the tracks such as large, rectangular or elongated shapes.

Analyzing a Part

First, consider the length, width, thickness, material weight and shape of the part. Look for any outstanding feature that may serve as a guide for orientation, such as; angles, grooves, flanges, bosses, projecting pins and convex or concave surfaces. These features should also be considered in relation to the centre of gravity and the overall size of the part. These features will determine the 'natural' feeding pattern of the part. Make the design of the part work for you, not against you.

Orientation is the control of the attitude of the part so they are in the correct position when they arrive at the designated workstation. By passing the part through a series of engineered obstructions or guides in the bowl track we provide orientation. The standard modular tooling is pre-engineered allowing Hamilton Feed Systems to reduce the troubleshooting and constant redesign in a typical feed shop. Occasionally, out-of-bowl devices such as orienting rolls or twist tracks may be invaluable in orienting headed or tapered parts.

The way a part feeds is affected by its material, proportions and dimensions (e.g. length versus diameter). A small change made to a part, though initially costly is often much cheaper than the cost of hand loading or otherwise feeding an un-feedable part. Some parts are inherently difficult to feed such as; lead wires on electronics components tend to tangle, unfired ceramics or powder metal parts break apart and oily parts tend to adhere to themselves and the bowl surface. We want to work with your engineering as required to change your parts to improve their feeding characteristics.

Coatings and Linings

Optional bowl linings such as Brushlon™, Urethane and Teflon™ are available for various needs or part characteristics. They are used for the following (among other reasons):

Noise reduction,
Ease of cleaning,
Enhanced part feeding,
Abrasive parts handling applications