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A new generator of PWM controller for AutoJet

Currently I am working on an alternative controller for AutoJet Technologies Spray controller made by Spray systems Inc.

I have been working on a more advanced and microprocessor controlled controller, it is intended to be used where the Model 1008 (AutoJet PWM driver modules, aka CP-PMDCT1008-XX) are not advanced enough or easy enough to install and set up.

The 1008-AutoJet device is a pure analog box, it needs to be programmed with potentionmeter/trimmer inside the device and can be controlled externally using industry standard 0..20mA current loop to control frequency of pulses.

The typical application I am looking at is the airless deposition of oils or emulsions used in the production of concrete products.

The oils or emulsions are used as releasing agents with high viscosity, mould release agents designed for the production of expanded concrete blocks. 

Deposition with air-driven nozzles leads to inaccurate placements of drops and waste of oil.
Furthermore, with air-less deposition volume and flow can be controlled without changing system pressure.

The valves open many times per second, for a precise time, at a precisely controlled interval.

The new cpu controlled board has features that an older generation analog system just can not compete with.

By digitally controlling the timing it can use many more patterns, more accuracy and easily handle integration with PLC systems.

Temperature compensation (for the change in viscosity of the oils) is also an option.

Flank or Level triggering of a pattern is possible, so using a single detector to detect a moving product will first allow for a controlled delay, a controlled ramp-up, a controlled number of pulses and a controlled ramp-down of flows.

Since more than one nozzle can be controlled, synchronisation between nozzles is easy and even more control options become possible, like interleaving spray units.

The logic control allows for remote and local alarms when pressure is too high or low, and in this way the controlling PLC can be instructed to halt the flow of materials until the problem is solved.

All this leads to better quality control and less waste, which is good for the bottom line and the environment.

Close up of spray nozzle and electromechanical actuators, used for air less deposition of oil or emulsion

Prototype controller, close up of menu screen showing configuration and logo options
prototype controller, microprocessor based, compatible with spray sytems inc

I will add more details about the advantages of using a cpu controlled system over the old analog system soon.

You can contact me at EDWIN AT OETELAAR DOT COM


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