Telemecanique Roller Conveyor Sensor Overview

Historically, when an object which is traveling down a conveyor needs to be reliably sensed, a photoelectric sensor is often employed.  The advantage is non-contact sensing, in either the proximity mode, the retro-reflective mode, or the through-beam mode.  Each mode has its tradeoffs, and limitations.  However, each of these modes has the photoelectric sensor(s) mounted above the surface of the conveyor, and viewing in the horizontal plane, across the width of the conveyor.  Depending on the application, sometimes if the product is relatively small with respect to the width of the conveyor, several sensors would have to be positioned above the conveyor, spaced equally apart, and looking down in the vertical plane, so as not to miss sensing the object for wherever it is located from side to side as it passed the detection site.  In either case, the disadvantage for either installation is that the sensor(s) themselves are physically just above the conveyor surface, and prone to being inadvertently dislocated and misaligned by the objects passing, personnel getting too close, or damaged by objects or forklifts removing palleted product from the conveyor.  In short, they are typically “in harm’s way”.

Several years ago, Telemecanique introduced a unique sensor, a single product which is mounted completely out of harm’s way and can sense objects virtually anywhere across the width of the conveyor.  This product is typically used on roller bed conveyors and installed in the space between consecutive rollers.  It is a single cylindrical rod, with multiple photoelectric sensors embedded within the rod, equally spaced apart, and faces straight upward to sense the object as it passes overhead on the conveyor.  Each of the multiple sensors in the single cylindrical rod is internally connected in a logic OR circuit, so if any one sensor, or multiple sensors sense the product presence, it will provide a single output.  Various lengths are available for different standard width conveyors, and the product is spring-loaded to fit a range of conveyor widths for any SKU chosen.  While this Telemecanique Roller Conveyor sensor is excellent for roller bed conveyors, it could also be used in the space at the junction of two belt conveyors.  Each photoelectric sensor within a single cylindrical rode has an IR source, and lens, to maximize the sensing distance and offer high immunity to the gradual accumulation of dust or dirt.

Aside from the intended application and installation on roller bed conveyors, this product has also been installed parallel to, and along the side rail, of a conveyor, looking across the width of the conveyor.  In this installation, the customer was looking to verify if any product was anywhere along the length of the conveyor, corresponding to the length of the roller conveyor sensor used.  A single product to replace multiple sensors.

Excel Automation/Eagle Sensor & Controls is an Authorized Distributor of Telemecanique products.  Please contact us for technical, application, and sales support.