| 摘要 |
PURPOSE:To make it possible to detect an object being invaded in a time differential manner by a first element pair and a second element pair, by crossing the arrangement direction of the first element pair and the arrangement direction of the second element pair by using two pairs of sensor elements. CONSTITUTION:The practical example of a crossing type double twin sensor system is shown by a drawing. In this case, a plus side sensor element a+ constituting a first element pair is arranged to the left upper corner part of a square while a minus side sensor element a- is arranged to the right lower corner part of a square. In addition, a plus side sensor element b+ constituting a second element pair is arranged to the left lower corner part of a square and a minus side sensor element b- is arranged to the right upper corner part of a square. When an object 3A to be invaded from the above in the drawing blocks the detection light axis between the first element pair and the second element pair or an object 3B to be invaded from the right in the drawing blocks all detection light axis, the object to be invaded is detected in the order from the plus sides a+, b+ to the minus sides a-, b-. |
