CN204832235U

CN204832235U - Tachometer based on AMR magnetic resistance switcher chip

Info

Publication number: CN204832235U
Application number: CN201520598359.3U
Authority: CN
Inventors: 余涛; 杨华; 张文旭; 彭斌
Original assignee: GUIZHOU YAGUANG ELECTRONIC TECHNOLOGY Co Ltd
Current assignee: GUIZHOU YAGUANG ELECTRONIC TECHNOLOGY Co Ltd
Priority date: 2015-08-11
Filing date: 2015-08-11
Publication date: 2015-12-02
Anticipated expiration: 2025-08-11

Abstract

The utility model discloses a tachometer based on AMR magnetic resistance switcher chip, include the pivoted camshaft together with vehicle electric motor rotor, at camshaft fixed AMR chip on one side, the permanent magnet is provided the AMR chip and corresponds the position and make the magnetic flux through the AMR chip reach saturated condition, and the camshaft is located the space that forms the magnetic wire between permanent magnet and the AMR chip, realizes when the camshaft rotates that the magnetic flux of process AMR chip changes, the utility model discloses the tachometer simple structure who makes, the volume is less, to installation environment require lowerly, and the environment of using is extensive.

Description

A kind of velocity gauge based on AMR reluctance switch chip

Technical field

The utility model relates to a kind of velocity gauge based on AMR reluctance switch chip, belongs to vehicle arrangement preparing technical field.

Background technology

The application of automobile in society is very general, along with the development of automobile industry, the support equipment of some automobiles is also developed gradually, wherein velocity gauge and velograph are requisite parts on automobile, this just illustrates that the velocity gauge of designing a novel practical and velograph are very important, the automobile-used velocity gauge adopted in the market and speedometer transducer are mainly divided into contact and contactless two classes, wherein the main operational principle of contact speed pickup is that sensor directly contacts with moving object, when moving object contacts with rotary speed pickup, the roller of friction force band dynamic sensor rotates, be contained in the rotational pulse sensor on roller, send out a series of pulse, each pulse represents certain distance value, thus just can measure linear velocity, contactless speed pickup mainly contains several as follows: (1) photo-electric vehicle speed sensor, be made up of rotating disk with holes, two optical conductor fibers, light emitting diode, phototriode as optical sensor, amplifier based on phototriode provides the signal of enough power, phototriode and amplifier to produce digital output signal (switching pulse) for engine control computer or ignition module, light emitting diode shines the transmission and reception that photodiode realize light through the hole on rotating disk, (2) magneto-electric vehicle speed sensor (accompanying drawing 1), usually be made up of the magnetic core of band two binding posts and coil, usual magnetoelectric sensor is built with Armco magnetic iron, make sensor in advance with certain magnetic field (accompanying drawing 1), when the detection of gear of magnetic conduction is near sensing element, because gear is magnetic conductive material, can make to be reduced (accompanying drawing 2) by the magnetic flux of coil, thus a voltage signal can be produced, the signal according to exporting measures the speed of a motor vehicle.This is also a kind of speed probe be most widely used in current automobile industry, (3) Hall vehicle speed sensor (accompanying drawing 3), in certain position, permanent magnet front end, Hall element is fixed, when the detection of gear of magnetic conduction is far away, the voltage signal produced under Hall effect through the magnetic flux of Hall element is not enough to make hall device export a magnitude of voltage, now Hall element exports as low level (accompanying drawing 3), when the gear of magnetic conduction is nearer, the magnetic flux through Hall element can be caused greatly to increase, because Hall effect can cause Hall element to export a high level (accompanying drawing 4), utilize this low and high level just can calculate the rotating speed of rotor.

Although said method is widely used in actual applications, but in use still there is certain problem, concerning with contact tachometer, in use easily wearing and tearing and causing are measured inaccurate, or even damage, this kind of sensor is generally applied in the electric automobile toy of low side; For photo-electric vehicle speed sensor, the support circuit needed due to it is comparatively complicated, and volume is comparatively large, and higher to the requirement in space during installation, this just significantly limit the use of photo-electric vehicle speed sensor; For magneto-electric vehicle speed sensor, because its principle of work is the change in voltage that the change of measuring magnetic flux brings, when rotor speed is lower, the signal voltage produced is less, thus may cause can't detect signal, and when rotor speed is too fast, the voltage signal of generation is larger, likely can reach the maximal value of subsequent conditioning circuit process and cause distorted signals, measuring inaccurate; And for the Hall element the most extensively adopted at present, due to the driving magnetic field comparatively large (generally at more than 40Oe) of Hall element, magnetic hysteresis comparatively large (generally at more than 8Oe), quiescent current comparatively large (being generally 10mA), there is response time delay when this just makes this kind of sensor be used in the environment of higher rotation speed or even situation about not responding occurs, this is just more painstaking concerning using the speed of a motor vehicle requires higher vehicle for some.And Hall element needs additional device more, driving magnetic field is comparatively large, and this just needs the permanent magnet that magnetic is larger, thus increases the volume of magnet, causes inconvenient when mounted.

Utility model content

The purpose of this utility model is: for the defect of prior art, and provide a kind of velocity gauge based on AMR reluctance switch chip, it is easy for installation, and small volume is highly sensitive, to overcome the deficiencies in the prior art.

The technical solution of the utility model

A kind of velocity gauge based on AMR reluctance switch chip, comprise the camshaft together rotated with vehicular electric machine rotor, at camshaft fixing AMR chip on one side, permanent magnet is arranged on AMR chip correspondence position and makes to be reached capacity state by the magnetic flux of AMR chip, camshaft is formed in the space of magnetic induction line between permanent magnet and AMR chip, and when cam axle, the magnetic flux realized through AMR chip changes.

Owing to have employed technique scheme, compared with prior art, the structure of the velocity gauge that the utility model is made is simple, small volume, lower to the requirement of installation environment, and the environment of application is extensive, the utility model only needs the less permanent magnet of employing one and an AMR reluctance switch chip just can realize sensing function; Permanent magnet can be placed on any one side of chip; The placed angle of permanent magnet can adjust as required, makes in-site installation very convenient.

Accompanying drawing explanation

Accompanying drawing 1 is structural representation when magnetoelectric tachometric transducer carries certain magnetic field;

Accompanying drawing 2 for during cam axle through the structural representation during magnetic flux change of magnetoelectric tachometric transducer

Accompanying drawing 3 is gear on camshaft structural drawing when not interfering with the magnetic flux entering Hall revolution speed transducer;

Accompanying drawing 4 be the gear on camshaft interfered with when entering Hall revolution speed transducer magnetic flux time structural drawing;

Accompanying drawing 5 is structural representation one of the present utility model;

Accompanying drawing 6 is structural representation two of the present utility model.

Embodiment

Below in conjunction with accompanying drawing to the utility model with being described in further detail, but not as to any restriction of the present utility model.

Embodiment of the present utility model: a kind of method for making of the velocity gauge based on AMR reluctance switch chip, the method adopts and fixes a permanent magnet on AMR chip side, adjustment angle makes to be reached capacity state by the magnetic flux of AMR chip, what at this moment chip exported is a low level signal (accompanying drawing 5), when the camshaft of motor is along with rotor rotation is through chip, because the gear on camshaft is permeability magnetic material, the magnetic flux through AMR chip can be made to be unsaturated state, what at this moment chip exported is exactly a high level signal (accompanying drawing 6), along with the rotation of rotor, chip can export a series of pulse signal, the rotating speed of motor can be calculated according to this signal.

A kind of velocity gauge based on AMR reluctance switch chip constructed by said method, as shown in drawings, comprise the camshaft 1 together rotated with vehicular electric machine rotor, at camshaft 1 fixing AMR chip 2 on one side, permanent magnet 3 is arranged on AMR chip 2 correspondence position and makes to be reached capacity state by the magnetic flux of AMR chip 2, camshaft 1 is formed in the space of magnetic induction line between permanent magnet 3 and AMR chip 2, and when camshaft 1 rotates, the magnetic flux realized through AMR chip changes.

Because AMR sensor has less driving magnetic field (being generally 15Oe), lower magnetic hysteresis (being generally 1.5Oe), less quiescent current (being generally 3 μ A), frequency is the highest can reach KHz, this just makes this product can be applied in higher rotating speed environment, and more reliable performance.

Claims

1. the velocity gauge based on AMR reluctance switch chip, comprise the camshaft (1) together rotated with vehicular electric machine rotor, it is characterized in that: at camshaft (1) fixing AMR chip (2) on one side, permanent magnet (3) is arranged on AMR chip (2) correspondence position and makes to be reached capacity state by the magnetic flux of AMR chip (2), camshaft (1) is positioned at the space forming magnetic induction line between permanent magnet (3) and AMR chip (2), and when camshaft (1) rotates, the magnetic flux realized through AMR chip changes.