Page 37 - Industrial Technology July 2021

SYSTEM INTEGRATION

Help get the beers in

SENSORS & SYSTEMS

WHEN A DRINKS PRODUCER NEEDED A METHOD OF CONDUCTING A FINAL INSPECTION CHECK OF
CASES OF BOTTLES AFTER THE LID OF THE CORRUGATED CARDBOARD CASE HAD BEEN CLOSED AND
SEALED, IT TURNED TO CONTRINEX. A BOTTLE COUNT IS PERFORMED BY VERIFYING THE POSITION OF
BOTTLE CAPS THROUGH LAYERS OF CARDBOARD AT THE TOP OF EACH SEALED CASE.

ottles that are packed into corrugated cardboard cases require the verification
of both the placement and number of bottles in the case, ideally after they have
had their lids hot-glued closed. A concern is that a bottle can break on impact
Bwith the bottom of the case, contaminating the machinery and subsequent
packages. Bottles can also be absent or wrongly positioned or a cap might be missing from
a bottle.
Whilst a vision system could be used, this would need to be done before the lid of the case
is closed, whereas verification of the closed case would be preferable. The absence of a bottle cap
in a specified position is a good indicator of a missing or shattered bottle and so the challenge is,
therefore, to detect bottle caps through multiple layers of corrugated cardboard material of varying
thickness and density.
Contrinex’s rugged extra-distance inductive sensors from the ‘500 Series’ are ideal for this
application, being robust and accurate. These highly reliable, IP67 rated, M30-diameter sensors
have a chrome-plated brass body with a PBTP sensing face and vacuum-encapsulated electronics.
Well suited to operating in a hostile environment, the 3x sensing distance of 22mm enables fully
contactless operation in this relatively high-speed packaging process.
A sensor array is placed over the conveyor and travel path of the cardboard cases. For each
lane of bottles in a case, an M30 diameter inductive sensor is mounted on the array. A non-
embeddable sensor is chosen as it most closely equates to the size of the bottle cap and yields
the greatest sensing distance for the available target area and is sufficient to allow for
minor variations in the height of the case as it passes under the sensor bridge. This not
only ensures reliable sensing but also keeps the sensor at a safe distance from any
impact, avoiding consequent downtime, with the sensors interfaced with a controller
that makes the logical decision to accept the package or reject and divert it.
MORE INFORMATION: www.pack.plusax.co.uk

July 2021 • INDUSTRIAL TECHNOLOGY 37