Flow gap solver

An inventor of novel techniques for restoring order to disturbed flows of food products on conveyors has now come up with two more novel marshalling prototypes.

Crafty Tech's Adrian Marshall, who developed the high-speed Marshalling Yard row aligner - which puts random multiple lanes of products back into rows - (licensed to SIG), has now developed a technique for controlling the speed and position of products as they slide down dead plates; a process particularly applicable to biscuit manufacture.

The trick of the invention is a system of switched porting behind the dead plate. This creates waves of vacuum which ripple down the dead plate at the desired speed and phasing. This vacuum wave will momentarily hold back any speeding product and then present a kind of 'moving obstruction' in front of the product, which will then force it to move with the vacuum wave rather than in freefall.

Assembling multiple such units side by side with matching travelling vacuum waves on each will not only regulate the sliding objects' speed, but because the products will reach the exit at a time related to the vacuum wave's motion, multiple lanes of product will be simultaneously re-aligned back into rows.

Typical applications might be in biscuit manufacture, where an existing slide system (known as a dribble board) is commonly used to improve laning, but unfortunately also tends to disrupt the row alignment. Re-engineering existing dribble boards to include the travelling vacuum wave technique would allow both lane and row re-alignment to be corrected.

And for situations where just occasional gaps between products are required, Marshall has invented a way of introducing a sporadic clear break in multi-lane flow, for example to allow a retracting conveyor to drop a group of product into a tray.

If product is well ordered then you just enlarge an existing gap by dropping a gate across the line (typically when a photocell says that there's enough of a gap), which then holds back the product to enlarge the gap appropriately. But with disturbed product flows there will not always be this initial clear gap to drop a straight gate into.

To address this problem, Marshall has devised an 'adaptive pusher blade'. This automatically changes its shape to miss obstructing product, but still retains a convoluted working face to allow a clear gap to be introduced into the product flow.

The basic idea is to use a matrix of pins, which is lowered over the product. Most importantly, the system automatically retracts any pins that would damage the product, leaving down only those that miss product, and which can then push on the edge of the product to 'nudge in' a gap.

The clever part of course is how you make the pins automatically retract to avoid product, and Crafty Tech's sensorless method underpins its latest patent. FM

Adrian Marshall will be presenting a paper The nuts and bolts of procuring novel process machinery​ at Food Manufacture's Profitable Production conference​ at the Heritage Motor Centre, Warwickshire on November 3. For more details about the conference visit www.foodanddrinkevents.com​ or call Helen Law on 01293 846587 email: helen.law@william-reed.co.uk