Many automated production processes use a conveyor belt installation. These belts use rollers and a conveyor belt. It is important to properly align the conveyor belt. This is also known as the product runway. Sensors are used to monitor and detect the alignment of the conveyor or products on it. This application is known as web edge guiding, belt edge guiding, web edge control or belt edge detection.
The rollers of these systems can also be used to feed a number materials instead of the conveyor belt. Think of foils, types of paper, metal sheets or textiles.
These materials are fed through the conveyor system and inspected by a fork sensor. The sensor is mounted on the track side so that the material flows through the fork opening. The fork sensor allows the controller to control the motors of the conveyor system with the correct speed and angle of the steering axle.
The material will not be damaged by misalignment over the web.
Less downtime due to errors and interventions leads to higher yields.
Less wasted material, because it can be used across the entire width.
Products are of a higher quality due to accurate cut markings and dimensions.
The material is detected by a fork-shaped ultrasonic sensor. The transmitter and receiver of the sensor are placed in front of each other while the material flows through and interrupts a part of the sent soundwave that does not arrive at the receiver. As a result, the sensor sends out an IO-Link, trigger, 4-20 mA or 0-10 V signal. Based on this signal the web and rollers can be guided. Production losses, faults and downtime are prevented this way. Ultrasonic sensors can be used on matrerials that pass by at high speeds because of the high response speed of the sensor. In addition, an ultrasonic signal is exceptionally suited for objects like foils, transparent materials and paper because of the insusceptibility to reflection and transpency.
Trackside detection can also be performed with light grids or laser light curtains. This is often done when it concerns airy material such as textile, woven or non-woven material, carpet, etc. It uses the same principle as with ultrasound; transmitter and receiver are placed opposite each other and if the signal deviates, the runway is adjusted.
Fork sensors or fork photocells can be used excellently for web edge detection due to the shape housing. The roller material or conveyor is fed through the fork opening of the sensor. The sensor is then set with parameters and tolerances to perform the measurement, detection or inspection. This may involve aligning the conveyor belt, counting products across the conveyor belt or inspecting a roll material such as duct tape.
