Richard Fisher

Notable features…

This is another system I was very pleased with. It ran fast very efficiently (not without it’s teething problems!), the customer was so pleased with it he ordered several more. All of the software was written in visual ‘C’ and used multi-threading for various sub sections of the application notably the PLC, image processing and user interface.

The company was Pico electronics.


We had an enquiry from a company that added value by inspecting fuses. The fuses where brought in and needed to be tested for continuity and the identification marking.

The continuity check was already in hand, what the company needed was a way to read the ratings on one end of the fuse and the safety markings on the other.

The requirements:-

What we came up with:-

How the system works…

vcl-fuse-hopperA set of three vibratory feeders feed the fuses in to the system.

The fuses are first loaded in to a bulk hopper, these are then trickle fed into a rotary bowl feeder, this is controlled by the computer to maintain a constant level in the rotary bowl. The fuses pass from the rotary bowl into the linear section.
The final linear feeder creates a steady controllable feed of fuses in to the system.


vcl-fuse-feedLinear to feeder tube via pneumatic actuator.



vcl-fuse-inspDown through tube into inspection area.

vcl-fuse-spinThe fuse is clamped between two rotating shafts and rotated under a line scan camera, this has the effect of flattening the fuse.

vcl-fuse-fuseThe optical character recognition finds the relevant text and symbols on the ends of the fuse, it is then compared against the expected result and a pass fail decision is made.

vcl-fuse-dropvcl-fuse-pfThe fuse drops into a small holding area until the pass fail decision is made, one of a pair of sliders then opens to allow the fuse to fall into either the pass of fail bin below.

The yellow devices in the picture are the inductive counters that verify that the fuse has dropped down the correct chute.

vcl-fuse-binsThe pass and fail bin. Any attempt to remove these while the system is running halts the test and invalidates any results.


An overview of the complete testing mechanism part way through the build.

My part in the project

This was one of my projects so I…




We also sold the company one of our Checkfast systems to check the integrity of the wire inside the fuse (not the continuity).



The top image shows a good fuse, the lower fuse may fail due to the small wisp of wire on the lower left. Other fails would include no wire or a broken wire.