Product Sensing - Labeling Systems, Inc.

Photo-Electric Sensors The most common method of giving a start signal is with the use of a photoelectric product sensor. Alternatives to using a photoelectric sensor can be using a PLC, relay, or a mechanical switch. Any of these methods are well suited to trigger the LSI labeler. Different types of sensors can be used to detect the product. The product size, shape, and color should all be taken into consideration when selecting a product sensor. Physical limitations for mounting the sensor must also be considered.
Diffused Beam Sensor This type of sensor is the most commonly used. The sensor emits a light, which reflects off of the product and is then detected by the sensor. The defused beam sensor does not require the use of a reflector. This sensor works well on products where there is an unobstructed area behind the product

Retro-Reflective Sensor This sensor requires the use of a reflector opposite of the sensor. The sensor emits a light, which is reflected off of the reflector and detected by the receiver in the sensor. When the product passes through the beam of light it interrupts the signal being received by the sensor. It then gives a signal to trigger the labeler.

Convergent Beam Sensor This sensor is used the least of all the sensors listed. This sensor is color sensitive and must be mounted at close range to the area being sensed, normally within one inch. It is very useful in detecting large differences in contrast such as sensing a registration mark on a web.

Infrared Thru-Beam Product Detector This sensor is comprised of an emitter and a receiver. Alignment of these components is critical. The thru beam detector is used to detect reflective products.

Fiber-Optic Most of the sensors listed in this section are available in a fiber-optic version. The sensors will operate in the same manner as described earlier in this section. The difference is that the emitter and receiver are mounted to the end of a fiber-optic cable(s). This type of scanner is used when the standard unit is too large to mount in a restrictive area.

Clear Product Sensors Different sensors are used by LSI for detecting clear products. The sensor is selected based on the product and the application. The sensors used are of the polarized retro-reflective type and will operate similar to a standard retro-reflective sensor. These sensors require a mirrored reflector for proper operation. Mechanical Switch Interface In certain applications it may be necessary to use a mechanical switch to trigger the labeling head. This is very useful in semi-automatic applications. A switch can be mounted in a fixture, which holds the product. When the product is placed in the fixture, it will trip the switch and trigger the machine. A foot pedal is also a common method used to activate the applicator in a semi automatic application.

Labeling Systems, Inc. LSI
32 Spruce Street
Oakland, New Jersey
Phone: 201-405-0767
Fax: 201-405-1179
Email: lsi@labelingsystems.com