Automated dispenser with sensor arrangement

摘要

An automatic electrically powered dispenser for dispensing a product stored in the dispenser includes an active IR sensor system for detecting a user. The IR sensor system includes at least one IR emitter and at least one IR receiver. The IR sensing system is arranged to scan for the presence of a possible user at a certain scanning rate. A sensor control system supplies the active IR emitter(s) with a first current which is constant during one or more single scans and is altered to a different, second current for further scanning. The first and second currents are determined on the basis of a signal strength of the average received IR which is received by the IR receiver(s) during a number of previous single scans. In a simplified system, the average value of the most recently received IR values may be compared to a standard value set in the control system to alter the current supplied to the IR emitter(s).