Passive reply device for use in the automatic wireless transmission of multi-place numerical information between active interrogation devices and such passive reply devices, which are movable with respect to one another and method of making the same

摘要

The invention relates to a passive reply device for use, for example, in automatic wireless transmission of multi-place numerical information between it and an active interrogation device which are movable with respect to one another, particularly for track-bound transport apparatus, which comprises a high frequency line section having a high frequency antenna at one end, and short circuited at its opposite end, and a plurality of high frequency coaxial resonators extending transversely to and carried by such line section, with a number of resonators being proportional to the number of places of the information to be transmitted. The resonators consist of individual elements which are inserted in appropriate bores of the line section with a press fit. The tuning of the individual resonators is determined by the particular shape of the bottom wall of each resonator, with the resonators otherwise being similar in construction. The invention also involves a novel method of effecting the tuning of the resonators by taking like resonators, formed from a relatively soft malleable metallic material and deforming the respective resonator bottom walls in axial direction inwardly and outwardly, by the application of external forces thereto, thereby effecting frequency shifts in the respective resonators.