There are various types of controllers / regulators which can be”tune used for controlling the speed of a vibratory bowl feeder. The foremost requirement in most cases is for a soft start electronic controller. The various types of controllers can be classified as follows -

Voltage Controllers – These vary the amplitude or the voltage and some do have voltage compensation provision i.e. to keep the output same even if there is a spike in input voltage. Usually, depending upon the rating of the vibratory feeder, the controller has to be selected. Normally, there are controllers having ratings of 3 Amps, 6 Amps, 8 Amps and 10 Amps. A good controller should also have overload cutoff provision (to switch off the controller when the current drawn exceeds the pre-set limit). This is required as otherwise, the coils might burn in case of any spike or in case the gap between the coil and the magnet increases due to any reason. Further there should be a soft start provision as also 1 to 2 different settings of soft starts (as one type of soft start cannot fit to all systems!). Elscint offers Model E3FC with a 3 Amp current rating and Model E5FC having 6 Amp current rating. These controllers have an overload cut-off provision as also settable soft start provision. The major disadvantage of voltage controllers is that the performance of a vibratory feeder changes in case there is a change in the input frequency (this happens in case there is a switch between generator power and that from the state board). This is because vibratory feeders work on the induction coils wherein even a small change in the input frequency has a huge effect on the output performance of the vibratory feeder.

Frequency Controllers – Voltage controllers vary the amplitude or the voltage while frequency controllers vary the amplitude / voltage as well as the frequency. The advantage of having a Frequency Controller is two fold. Firstly, in case there is a change in the input frequency, the speed / performance of the vibrator does not change. That means that even if you switch between generator power and that from the state board, there will be no change in the performance of the vibratory feeder. Secondly, with a frequency controller, one can change the “tune the vibrator”. That is the manual process of “tuning” of a vibrator which is increasing / decreasing the springs to ensure that the vibrator works well can be done by changing the frequency on the controller. This makes it very convenient in the long run if the performance of the vibrator springs deteriorate over time. In case of frequency controllers, there are analog as well as digital frequency controllers. Elscint_Fre_01 and Fre_02 – These are manual frequency controllers with two potentiometers, one for frequency and one for voltage. These provide highly stable performance and can guarantee constant voltage and constant frequency to the vibrator unit. These are available at very competitive prices. These are of tremendous value in case of intermittent usage of Genset. Elscint EFQ1 – This is a digital automatic tuning frequency controller which searches for the correct resonant frequency of the vibrator.

Feedback Controllers – These have a sensor attached to the springs of the vibrator which provides feedback of the load in the vibratory feeder to the controller. The micro-chip in the controller takes this feedback and adjusts itself accordingly. This is of tremendous value in case of changing load and heavy components.

Double Speedy – In all models, DOUBLE SPEEDY is available i.e. two Potentiometers are given whereby one is used for course adjustment and one for fine adjustment. These are of tremendous use in case of weighting and batching systems.

Elscint controllers are specially designed for controlling the amplitude of vibration in industrial electromagnetic vibrators.
The system is based on a integrated circuit which guarantees perfect synchronisation of the triac firing pulse with the waveform of the working voltage under all conditions.
Another thing to look for in a vibrator controller / regulator is whether it can operate at 50Hz or 60Hz.

Vibratory bowls can be made out of various types of material, mild steel, stainless steel, brass, polyamide etc. Out of these, one can get the best performance from cast aluminium bowls. Bowls made of mild steel are not long lasting due to rusting and not wear resistance. Over time, their performance deteriorates drastically. Aesthetic wise too, it does not look good, even if painted. Hence, it is not recommended to use mild steel bowls. Polyamide bowls have certain advantages like machining ease and repeatability but the disadvantages are the size (small) and type (conical). Step design bowls, which provide a lot of tooling flexibility, convenience and high loading volumes are not always possible in case of polyamide bowls. These disadvantages are not there in stainless steel and cast aluminum bowls. The advantages of these types of bowls are tooling flexibility, convenience and high loading volume. Secondly, it is possible to provide irregular and complicated bowl tooling and shapes in case of stainless steel fabricated bowls. However, the disadvantage is that as they are fabricated, there is a chance of manual error while making and tooling them. If they become unwieldy or else are not properly tuned, they do not work properly, especially at certain areas. This creates problems for the customer in the long run as a lot of dead stock is required to be maintained in the bowl and secondly, there might be chances of wrongly oriented components going forward. As against these, the advantages of using cast aluminum bowls are the ease and speed of tooling and lower cost. Plus they are modular in construction. In case the part for which they are manufactured, changes, they can be retooled for another part. However, proper coating is required for all cast aluminum bowls. Elscinthane spray able polyurethane coating is the best choice for cast aluminum and stainless steel bowls. Not only does the coating reduce the noise level in case of metallic components drastically by eliminating the metal to metal contact, but the life and performance of the bowl improves drastically. Further using a cast aluminium bowl eliminates a lot of problems of the bowl becoming unwieldy or not properly tuned. Hence, insisting on a cast aluminium bowl with polyurethane coating can help reduce the dead spots. 

In most of the cases, it is better to have feeder bowls coated. Coatings can be either polyurethane spray coating, pasting of sheets on the bowl surface, teflon coating etc. The best solution lies in polyurethane spray coating. The advantages are firstly, in case of metallic components, the Noise Level can be drastically reduced by eliminating the Metal to Metal contact between the metallic bowl surface and the components. Another major problem faced by customers is of feeding oily components. Oily components reduce / eliminate the friction between the components and the Bowl track. As Vibrators work on the principle of Friction, this results in the components slipping and hence they are not able to feed properly. Proper type of coating can eliminate this. It is better to have a rough coating in case of oily components while in case of dry components, it is beneficial to have smooth coating. This improves the friction between the components and bowl, resulting in better movement of parts forward. Previously, PVC or polyurethane sheets were pasted to the bowl surface to act as lining. However, these have many disadvantages. First and foremost, in case the adhesion is not proper at any place, air bubbles get created and the whole sheet gets removed. Even if any adhesive is used, it gets removed in cases where there is oily residue on the components.