| 摘要 |
The position of parallelepiped-shaped objects on a first receptacle is detected by means of a detection device using an optical reader operating on a position mark carrier which has two label portions intended to arise on different ones of two adjacent sides of the object, one of the sides being larger than the other. Each of the label portions has a respective identification mark so that not only does the label indicate the nature of the object, it also identifies which of the two adjacent faces of the object is being scanned by the optical reader. Furthermore, means are provided for measuring the distance of the optical reader from the scanned side of the object, by relying on angular deflection of a scanning beam at a given constant angular velocity and measurement of the time taken to scan the label portion which has a predetermined constant length. The position mark carrier has two label portions each of which bears the same bar code to identify the object and additional markings in association with the bar code for identifying the particular label portion, and hence the particular face of the object, which is being scanned. The apparatus is capable of scanning horizontally to discover the position of the nearest set of objects on a first receptacle, and then repeating that horizontal scan to process the next adjacent objects, and so on until the top layer has been removed. Then the scanner is indexed downwardly through a distance equivalent to the height common to the objects, and the process on the next uppermost layer is repeated, and so on until all of the objects have been removed from the first receptacle. |
