Magnetism reading device for coil magnetic core full bridge structure

Abstract

The invention discloses a magnetism reading device for a coil magnetic core full bridge structure. The magnetism reading device is connected with a main processor of a false proof detection device, and includes a housing, wherein a permalloy shielding shell and a difference amplification module are arranged in the housing; a working window is arranged in the length direction of the permalloy shielding shell; a plurality of independent detection channels are arranged in the working window successively; each detection channel is a Wheatstone full bridge structure which is formed by four magnetic induction units; the Wheatstone full bridge structure is used for inducing changes of the magnetic field and outputting a differential voltage signal to a difference amplification module; and the difference amplification module can be used for restraining a common mode input signal and amplifying the differential mode input signal, and can output a magnetic characteristic false proof signal of an object to be detected to the main processor of the false proof detection device, so that the anti-electromagnetic interference performance of a domestic traditional coil+magnetic core type magnetic reading sensor and the signal to noise ratio of the output signal, and the performance requirement for the anti-electromagnetic interference performance of the magnetic reading sensor and the signal to noise ratio for the false proof detection device can be satisfied.

Description

technical field [0001] The invention relates to anti-counterfeiting detection and identification technology, in particular to a magnetic reader with a full bridge structure of a coil magnetic core. Background technique [0002] The serial number, pattern ink and metal security thread on various large-denomination banknotes such as RMB, Euro, and U.S. dollars are all distributed with magnetic materials, recording anti-counterfeiting information with magnetic characteristics. [0003] In order to judge the authenticity of banknotes, bank automatic deposit machines (ATMs) and high-end banknote checking and sorting machines must be equipped with magnetic reading sensors that can read the anti-counterfeiting information of the magnetic features on the banknotes, and read the anti-counterfeiting information of the magnetic features of banknotes read by the sensor. It is processed to identify the authenticity and denomination of the checked banknotes. [0004] Bank automatic depos...

AI Technical Summary

Problems solved by technology

[0007] In view of the shortcomings of the above-mentioned prior art, the object of the present invention is to provide a magnetic reader with a full bridge structure of a coil magnetic core, aiming at solving the problem of the anti-electromagnetic interference performance and output signal of the existing coil + magnetic core type magnetic reading sensor. The signal-to-noise ratio is poor, so it cannot be used for anti-counterfeiting detection equipment such as bank automatic deposit machines (ATMs) and high-end banknote checking and sorting machines.

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