8
Object Detection:
The Firefly Curing System uses sensors at the
front of the heat chamber to detect objects
entering the dryer (Figure 12)
Object Detection
Sensor(s)
Sensor Status
Light(s)
Sensor Target(s)
(Under Belt)
Figure 12: Object Detect Sensor(s)
Object entering the chamber MUST trip the
sensor in order for the dryer to operate correctly.
Undetected product will not activate the
machine, and may result in uncured or under
cured ink.
Object Detect
Sensor
Figure 13: Tripping Object Detect Sensor
The object detect sensor works by shining an
invisible (Infrared) beam of light down through
the belt, and detecting the reflection off a target
located below the belt (Figure 14).
As an empty belt travels around the dryer, the
target is detected, the sensor status light
illuminates, and the machine knows that no
product is entering the cure chamber.
Em pty
B elt
N o
Product
D etected
Sensor
Status
Light
O bject
D etection
Sensor
Sensor
Target
(U nder B elt)
Figure 14:Object Detect Sensor Empty Belt
When product is laid on the belt and travels
under the object detection sensor (Figure 15), it
covers the target and the sensor status light turns
off. The machine now knows that product is
entering the heat chamber, and activates the
heating elements.
Normal
Product
Product
Detected
Figure 15:Object Detect Sensor Normal Product
It is important that both the sensor lens and the
sensor target are kept free of dust and lint so the
light beam can be emitted and detected correctly.
If dust or lint blocks the light beam enough,
product may be detected even on an empty belt,
resulting in heater elements activating when they
are not needed, resulting in lower efficiency and
reduced bulb life.
