Label is a type of paper that is printed on something. It provides total information about it. This includes its ingredients, manufacturing and expiring date, and details about the manufacturer.
Pasting a label on a material is not a tough task But In industry where production is happening in millions. Label pasting process requires heavy man-power & heavy investment.
But with the help of automation, Label pasting process can becomes easy & fast. Automation also reduces the man-power & Chances of error.
PLC & HMI are the main components of Automation. But these components works on the behalf of inputs from the sensors. For label detection, A sensor should be there.
There are multiple types of sensors available for label detection with different types & shapes. These sensors are chosen according to need.
In this post, We are going to discuss Fork type photo Electric sensor .
FORK PHOTO ELECTRIC SENSOR
Photo Electric sensors works on light energy. These sensors are equipped with two main parts ‘emitter‘ & ‘receiver‘. Emitter emits light While receiver receives light. On receiving the light energy from emitter, Electronics circuit located in receiver, Produces an Electrical signal either High or Low.
A GIF shown below shows the working of photo electric sensor . In normal conditions, when there is nothing between the emitter and receiver. The receiver receives a light signal and produces an electrical signal.
But when some obstruction get in between emitter & receiver, A light signal get disconnected.
Fork type photo electric sensors are specially designed in a shape of fork through which label passes. On both the sides of the sensor emitter & receiver are arranged.
For better understanding, We are going to discuss the sensor GS 63B/6D
by Leuze. It is specially made for label detection.
SPECIFICATIONS OF PHOTO ELECTRIC SENSOR 63B/6D LEUZE
- Sensor is 3 wired.
- 2 wires brown(positive) & blue(negative) are the power supply terminals.
- Power supply voltage ranges from 10 to 30 V DC.
- 3rd black wire is power output with current rating of 100 mA. Voltage output is Ub-2 Volt.
- Sensor is having polarity reversal protection.
- It is also having a short circuit protection.
- For sensitivity adjustment; Sensor includes a potentiometer knob.
- Sensor includes power supply indicator & Output Indicator.
- Mouth’s width is 3 mm & mouth Gap 61 mm.
CONNECTION DIAGRAM PHOTO ELECTRIC SENSOR 63B/6D LEUZE
This sensor is having three terminals In which 2 terminals brown(positive), Blue(negative) are supply terminals. Voltage range from 10 to 30 V DC. The 3rd terminal is output terminal.
Third Black terminals produces output voltage of Ub-2 Volts. (Ub= Input voltage)
WORKING OF PHOTO ELECTRIC SENSOR 63B/6D LEUZE
This GS 63B/6D sensor is specially designed for non-transparent labels. There should be a smallest label width of 2 mm and a least label gap of 2 mm.
Both the fork opposite to each other holds emitter & receiver. Sensor emits infrared light with the wavelength of 940 nm.
An collage image of working sensor is shown above. When there is nothing in between the fork, Emitter’s light completely received by receiver. Sensor produces an output signal.
But when there is some obstruction between the fork, Receiver do not gets any light, sensor discontinuous output.
” A GIF above shows the working of label sensor on production line.
Label reel consists of multiple labels in a row. Both labels & label gap paper have fixed size. Label reel continuously passes through the sensor’s fork.
Labels are dark in color while label gap papers are light in color. At label gap paper, Emitter’s light passes through paper & reaches to receiver. While on labels, Emitter’s light can not cross.
As per according to label gap paper, Sensor sensitivity can be adjusted. Sensitivity should be adjusted such that sensor only recognize the label. “
CONCLUSION
Photo Electric sensors works on light energy. It has the both emitter & receiver. Emitter emits light energy while receiver receives light energy. According to light presence on sensor’s receiver, Sensor produces an output.
Similarly there are fork type photo electric sensors . Which are specially made for label detection in shape of fork. Through the fork of the Sensor , label passes through. Both the sides of fork contains Emitter & Receiver.
Label Sensor , count the presence of the label & produces an output to PLC.