| 摘要 |
The appts. includes a transversal transporter (10) with a transport surface limited by two side edges (10'). Light emitter and receiver components (13,14') are arranged adjacent to at least one of the side edges so that a measurement zone (M) is produced tightly over the transport surface. A monitor (12) is provided for the movement of the transporter, and an electronic unit (15) receives signals from the receiver and from the monitor. The emitter and receiver components are arranged so that the measurement zone is limited by two sharp limit lines (13a) which are not parallel, so that the measurement zone has an extent in the transversal transport forward feed direction (P) which varies dependent upon the position between the edges. The light emitter is a laser (13), and emits a diverging radiation light bunch, and the light receiver is two units at a distance (A) from each other in the transport direction (P) with two line-form narrow sight fields converging towards each other. @(11pp Dwg.No.1/5)@ |
