05438960 is referenced by 4 patents and cites 9 patents.

A detection and weighing device for selectively distinguishing two groups of animals, such as for instance cocks and hens, one of the groups to be distinguished being provided with a detection element, for instance a label, consisting of or provided with amorphous magnetic material. This material is recognized with the aid of an alternating magnetic field and a receiving coil suitable for that purpose, and the presence or absence of the detection element, together with the weight determined by the weighing device on which the detection system is arranged, indicates whether an animal from one group or the other group is involved, so that, for instance, the average weight of the two groups can be determined. Instead of being used in combination with a weighing device, this detection device can also be used while being coupled to other presence-detection devices. Further, the number of groups to be identified can be enlarged by using amorphous magnetic materials with distinguishable differences in magnetic properties.

Title
Detection device for selectively distinguishing from each other a number of groups of articles or animals
Application Number
8/123966
Publication Number
5438960
Application Date
September 21, 1993
Publication Date
August 8, 1995
Inventor
Dirk J Roosenboom
Haaksbergeb
NL
Agent
Jacobson Price Holman & Stern
Assignee
N V Nederlandsche Apparatenfabriek NEDAP
NL
IPC
A01K 29/00
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