Usually a Vibratory Bowl Feeder manufacturer would prefer only one job to be fed through one Bowl Feeder but customers always have requirements of feeding of multiple jobs in the same Bowl Feeder. One way of feeding such multiple components is to provide separate bowls for different components and another, more difficult way is to accommodate all the components in the same bowl and make provision for simple “Changeover Tooling”. However, in such a case, it is pertinent that the multiple jobs to be fed through one Bowl Feeder are from one “family” of components though their dimensions might defer. To give an example, all the jobs should have diameter less than length. There should not be multiple jobs where some jobs are having diameter less than length and some jobs where the diameter is more than length. Or in case of caps, all the caps too should be having either diameter more than the height or else height more than diameter. A mixture of these two types is difficult to orient and feed in the same Bowl Feeder. Of course, this too can be done but requires more expertise on the part of the bowl feeder manufacturer. Most Vibratory Bowl Feeder manufacturers regret such inquiries or convince the customer to buy multiple bowls, which cost the customer a lot. Plus changing Bowls is not always an easy affair and might require retuning the Vibratory Drive after each change. However, Elscint Automation possesses a rich expertise of working on multiple components of various sizes and dimensions (even the difficult ones detailed above) and can provide a single Bowl for even different families of Components. 

1] Start the bowl feeder and with the help of the regulator set the input voltage to 80% of the rated voltage of the coil for the model you have selected

2] Slowly loosen the bottom screw of one of the spring packs. As this screw is being loosened there will be a change in the feeding speed of the workpieces. If:

·      The feeding speed decreases, install additional springs. To start with add one spring in one spring pack, if this is not adequate then add one by one additional springs in the remaining spring packs. Repeat this procedure if feeding speed is not adequate.

·      The feeding speed increases, remove springs from the spring pack. To start with remove one spring from one spring pack, if this is not adequate then remove one by one springs from remaining spring packs. Repeat this procedure if feeding speeds are not adequate.      

4] If feeding speeds on the periphery of the bowl are irregular, then:

·      Remove one spring from the slow feed zone.

·      Add one spring to the fast feed zone.

5] If the feeding speed is irregular on a track which is in between two spring packs, then you may add or remove the spring behind the irregular spot. This is to be seen with respect to the hand of the bowl.

Vibratory Bowl Feeder manufacturers provide “tooling” on the tracks of the Bowl. As the components / parts go up the spiral, this “tooling” obstructs the movement of the components by making them change their flight path. This results in the components changing their orientation and moving ahead in the required orientation. It requires a good Bowl Tooler to design a good Bowl Feeder. A bad Bowl Tooler will provide you with the “tooling” but it will not be perfect with a “wrong” type passing thru’ every once in a while. Hence, it is pertinent that one buys Vibratory Bowl Feeders from the correct source / right company.

Vibrations have fascinated human beings since a very long time. Virbatory Bowl Feeders are around since the early part of the Twenthieth Century. No major alternative to a Vibratory Bowl Feeder has been invented in the meantime. Rotary Feeder which uses a motorised drive is a very poor cousin of the Vibratory Bowl Feeder. (We will discuss the advantages / disadvantages of using a Rotary Feeder vis a vis Vibratory Feeder in another write up).

What are Vibratory Bowl Feeders used for?
Vibratory bowl feeders are commonly used for aligning and feeding of small parts. They are the very versatile and widely used for feeding of parts in an automatic assembly. 

What is a Vibratory Bowl Feeder? And how does it work?
Vibratory Bowl Feeders are used for feeding of components to various Machines. The actuation / Vibrations take place by electromagnets. The Vibratory Bowl Feeder is a device that converts Electro-magnetically produced vibrations into mechanical vibrations. These mechanical vibrations are utilised for movement of the workpiece along the track of the Bowl Feeder.

Magnetic coil, which is fixed to the counter mass is energised with supply of electric current, producing a force, which in turn attracts and releases the magnet armature. As the magnet is rigidly fixed to the top spring holder and bowl feeder, the vibrations are transferred to the spiral-conveying track of the bowl. Depending on the angle of gradient of the leaf springs and lead angle of the helix of conveying track, the workpieces move with every vibration above the track in small jumps.
                                   
During one period of 50 cycle AC mains the magnet attains its maximum attraction twice since the magnetic force is not dependent on the direction of current flow. Thus the magnet produces a vibrating frequency of 100 cycles, which is necessary for smooth & reliable movement of small & light weight workpieces. Some Bowl Feeder manufacturers use 50 Cycles / HALF WAVE Bowl Feeders too. The biggest advantage of a 100 cycle / FULL WAVE Vibratory Feeder is that it consumes almost 40% less energy as compared to a HALF WAVE Vibratory Feeder. Secondly, as the vibrations are smooth and reliable, the parts being fed do not get damaged, which is a possibility in case of HALF WAVE bowl feeders.

Thus a vibratory bowl feeder consists of a bowl mounted on a base by three or four inclined leaf springs or packs of springs. The springs constrain the bowl so that, as it travels vertically. As the components move up an inclined track along the edge of the bowl, the tooling in the bowl orients the components into the required orientation or rejects the misaligned parts into the center of the bowl where they begin their travel up the track again. One to six electromagnets, mounted on the lower counter weight / heavy base, generates the force to drive the bowl feeder. The Counter weight rests on rubber feet, which serve to isolate the vibration of the Vibratory feeder.

The components are conveyed in the bowl by one of two modes: sliding or hopping. In the sliding mode, motion is produced from friction between the part and the bowl. As the bowl rises and turns, the friction between the track and the part pushes the part forward with the track. When the track descends and turns backward, the force of friction is smaller and the part slides forward relative to the bowl. In the hopping mode, the part moves forward with the bowl as it rises and turns, but it experiences freefall when the bowl's downward acceleration exceeds the acceleration of gravity. During free-fall, forward motion is created as the bowl moves backward relative to the part.