CN2788259Y

CN2788259Y - Huge magnetic resistance sensor of paper money counter

Info

Publication number: CN2788259Y
Application number: CN 200520095968
Authority: CN
Inventors: 陈鼎柱; 刘敏文; 苏鸣新; 陈加乐
Original assignee: FUJIAN FILM MACHINERY FACTORY
Current assignee: FUJIAN FILM MACHINERY FACTORY
Priority date: 2005-04-15
Filing date: 2005-04-15
Publication date: 2006-06-14
Anticipated expiration: 2015-04-15

Abstract

The utility model provides a giant magnetic resistance sensor of a paper money counter, which adopts a giant magnetic resistance (GMR) sensor chip as an induction chip for detection. The giant magnetic resistance sensor of a paper money counter is composed of a casing, a GMR chip, magnetic steel, a core frame, a binding post, etc., wherein the GMR chip, a PCB board and the magnetic steel are arranged in the casing frame top to bottom via the core, and the magnetic force line produced by the magnetic steel is parallel with the wiring direction of the giant resistance on the surface of the chip when passing through the chip of the giant magnetic resistance sensor. In this way, the magnetic steel provides suitable operating environment for the GMR chip; the magnetic signal of the paper money to be checked performs the function on the chip, and the resistance differential value is generated by the GMR chip; therefore, the detection signal is generated to be provided for the paper money counter, and the fake-detecting process of the paper money is completed. The giant magnetic resistance sensor of a paper money counter, which is provided by the utility model, has the advantages of small volume, high sensibility and good linearity; when working, the utility model has good temperature characteristic, high reliability and low production cost; the giant magnetic resistance sensor of a paper money counter is the product for replacing various magneto-dependent sensors used for the paper money counter/detector.

Description

The giant magnetoresistance sensor of paper money counter

Technical field:

The utility model belongs to a kind of sensor that is used to measure magnetic variable, particularly a kind of giant magnetoresistance sensor that is used for paper money counter.

Background technology:

Utilizing false proof magnetic material on the Renminbi to carry out currency examine is existing paper money counter and cash inspecting machine technological means commonly used.Magneto-dependent sensor on the paper money counter converts the magnetic signal on the false proof magnetic stripe on the Renminbi to electric signal, judged identification after tell true and false paper money.The magneto-dependent sensor that uses on the present stage currency counter mostly is the MR chip, the magnetic line of force direction of externally-applied magnetic field is perpendicular to chip, utilize the Renminbi magnetic stripe through out-of-date generation magnetic line of force direction change, magnetic field size etc. detects the variable that chip produces, thereby carries out false proof.But the transducer sensitivity of the traditional MR chip of existing employing is low, and temperature characterisitic is poor, and reliability was not high when paper money counter used.

Summary of the invention:

The purpose of this utility model provides a kind of giant magnetoresistance sensor of paper money counter, and it adopts giant magnetoresistance (GMR) sensor chip as induction chip, good temp characteristic, and the reliability height has improved detection sensitivity simultaneously.

The technical solution of the utility model is: a kind of giant magnetoresistance sensor of paper money counter, by shell, chip, magnet steel, compositions such as core frame and binding post, described chip, magnet steel and core frame are installed in the enclosure, it is characterized in that the magnetic shielding shell has a window, chip is placed in this window, its lower end is fixed on the pcb board, the lower end of pcb board is fixed on a core frame upper end, described chip adopts giant magnetoresistance (GMR) sensor chip, and the magnetic line of force that magnet steel produces parallels with chip surface giant magnetoresistance wiring direction during by this giant magnetoresistance sensor chip.Offer the suitable working environment of GMR chip by magnet steel like this, the magnetic signal on the bank note that needs to detect acts on the chip, produces the resistance difference by the GMR chip, offers paper money counter thereby produce detection signal, finishes the inspection pseudoprocess of bank note.

The giant magnetoresistance sensor of paper money counter provided by the utility model has that volume is little, highly sensitive, the advantage of good linearity, good temp characteristic during work, the reliability height has lower production cost simultaneously, is the existing regeneration product that is used for the various magneto-dependent sensors of point (testing) paper money machine.

Description of drawings:

Fig. 1 is the structure cut-open view of the giant magnetoresistance sensor of this paper money counter.

Fig. 2 is the plan structure synoptic diagram of Fig. 1.

Fig. 3 is GMR chip, magnet steel direction and the Distribution of Magnetic Field synoptic diagram of the giant magnetoresistance sensor of this paper money counter.

Fig. 4 is the giant magnetoresistance chip features figure that this sensor uses.

1-GMR chip wherein; 2-pcb board; 3-core frame; 4-magnet steel; 5-shell; 6-binding post; 7-foot of the ground wire.

Embodiment:

Describe embodiment of the present utility model in detail below in conjunction with accompanying drawing.As shown in Figure 1 and Figure 2, the giant magnetoresistance sensor structure of this paper money counter is made up of shell 5, GMR chip 1, pcb board 2, magnet steel 4, core frame 3 and binding post 6 etc.The upper end of described shell 1 has a window, and GMR chip 1 is placed in this window, and in order to prevent excessive friction damage chip, the upper end of chip 1 is a little less than the outside surface of this window.The pcb board 2 that is connected with chip 1 lower end is fixed on core frame 3 upper ends.Core frame 3 is provided with the magnet steel fixed orifice by injection molded under its corresponding chip, described magnet steel 4 is installed in this fixed orifice.The direction of magnet steel is decided according to the direction of chip, but parallels with chip surface giant magnetoresistance wiring direction must guarantee the magnetic line of force by this giant magnetoresistance sensor chip the time, as shown in Figure 3.

Giant magnetoresistance (GMR) the chip wiring feature that this sensor uses as shown in Figure 4.The wiring of this chip is made up of two parallel giant magnetoresistances, and wherein every resistance width B is 0.04 millimeter, and length C is 2.5 millimeters-3.5 millimeters, and the parallel distance A between them is less than 0.1 millimeter.

Shell 5 adopts the permalloy materials to make in this embodiment, can be effectively to external world electromagnetic interference signal shield, thereby further improve the functional reliability of this sensor.

Claims

1, a kind of giant magnetoresistance sensor of paper money counter, form by shell, chip, magnet steel, core frame and binding post etc., described chip, magnet steel and core frame are installed in the enclosure, it is characterized in that the magnetic shielding shell has a window, chip is placed in this window, its lower end is fixed on the pcb board, the lower end of pcb board is fixed on a core frame upper end, described chip adopts giant magnetoresistance (GMR) sensor chip, and the magnetic line of force that magnet steel produces parallels with chip surface giant magnetoresistance wiring direction during by this giant magnetoresistance sensor chip.

2, the giant magnetoresistance sensor of paper money counter according to claim 1, the position that it is characterized in that described magnet steel be positioned at giant magnetoresistance (GMR) chip under, magnet steel polarity parallels with chip surface giant magnetoresistance wiring direction.

3, the giant magnetoresistance sensor of paper money counter according to claim 1 and 2, it is characterized in that the corresponding chip of described core frame under be provided with the magnet steel fixed orifice, described magnet steel is installed in this fixed orifice.

4, the giant magnetoresistance sensor of paper money counter according to claim 1 is characterized in that described shell adopts the permalloy material to make.

5, the giant magnetoresistance sensor of paper money counter according to claim 1, the wiring that it is characterized in that described giant magnetoresistance chip is made up of two parallel giant magnetoresistances, every the resistance width is 0.04 millimeter, length is 2.5 millimeters-3.5 millimeters, and the parallel distance between them is less than 0.1 millimeter.