CN211476994U

CN211476994U - Anti-interference displacement sensor

Info

Publication number: CN211476994U
Application number: CN202020399624.6U
Authority: CN
Inventors: 陈恩伟; 周剑敏
Original assignee: Zhejiang Wodell Technology Co ltd
Current assignee: Zhejiang Woder Technology Group Co.,Ltd.
Priority date: 2020-03-26
Filing date: 2020-03-26
Publication date: 2020-09-11
Anticipated expiration: 2030-03-26

Abstract

The utility model relates to an use the sensor on the car, especially relate to an anti-interference displacement sensor structure. The utility model provides an anti-interference displacement sensor, includes sensor housing, installs the PCB board in sensor housing, installs the anti hall sensor chip that scatters magnetic field interference on the PCB board, is equipped with magnet in one side of PCB board, the magnetic field intensity at magnet middle part be greater than the magnetic field intensity of magnet both sides, the magnetic field angle is single-way change along with the displacement, the change of magnetic field angle is linear. The utility model provides an anti-interference displacement sensor which can effectively eliminate magnetic field interference, improve measurement accuracy and meet various use requirements; the problem of among the new forms of energy car that exists among the prior art, variable incasement electromagnetic components is many, and the sensor receives electromagnetic interference easily, influences the technical problem of precision is solved.

Description

Anti-interference displacement sensor

Technical Field

The utility model relates to an use the sensor on the car, especially relate to an anti-interference displacement sensor structure.

Background

At present, automobiles are applied more and more widely. With the increasing loss of non-renewable resources and the influence on environmental protection, the hybrid electric vehicle and the pure electric vehicle are added to the existing vehicles in addition to the original fuel vehicles. At present, the popularity of new energy vehicles in the whole vehicle market is continuously increasing, and the new energy vehicles carry multiple times of complex circuits and complex electromagnetic environments of traditional vehicles. Under such environment, gearbox environment interference magnetic field is big, leads to all kinds of sensors to appear abnormal conditions. The accuracy and the performance of the sensor are greatly reduced.

Disclosure of Invention

The utility model provides an anti-interference displacement sensor which can effectively eliminate magnetic field interference, improve measurement accuracy and meet various use requirements; the problem of among the new forms of energy car that exists among the prior art, variable incasement electromagnetic components is many, and the sensor receives electromagnetic interference easily, influences the technical problem of precision is solved.

The above technical problem of the present invention is solved by the following technical solutions: the utility model provides an anti-interference displacement sensor, includes sensor housing, installs the PCB board in sensor housing, installs the anti hall sensor chip that scatters magnetic field interference on the PCB board, is equipped with magnet in one side of PCB board, the magnetic field intensity at magnet middle part be greater than the magnetic field intensity of magnet both sides, the magnetic field angle is single-way change along with the displacement, the change of magnetic field angle is linear. In a traditional 3D hall mode, a group of hall elements perpendicular to each other are used to measure X, Y, Z magnetic field components respectively, and a magnetic field angle is calculated. In order to meet the requirements of the existing new energy vehicle, the chip needs to be replaced by a chip in an anti-stray differential mode. Two groups of Hall units with the interval of 2.15mm are used for measuring magnetic field components of X1, Z1, X4 and Z4 respectively to obtain differential signals delta X and delta Z, and a magnetic field angle is calculated. Thereby eliminating common mode magnetic field interference. Aiming at a new anti-stray difference mode of the chip, the magnetic field is non-unidirectional after the difference of the conventional magnet, the mode is a curve mode, and after the difference exceeds 360 degrees, the curve has an inflection point, so that the output curve graph cannot meet the use requirement of the new chip. Therefore, the utility model discloses designed magnet according to emulation and actual measurement means, strengthen the magnetic field intensity at magnet middle part, let its linear precision more accord with anti stray differential mode, improve the anti-interference level of sensor in the car, export more reliable and stable signal. The angle of the magnetic field changes unidirectionally with displacement, and the same angle cannot be generated under different displacements. The magnitude of the magnetic field is above 10mT as much as possible. The stability of the sensor is improved, the service life of the product is prolonged, and the failure information of the vehicle misjudgment sensor is reduced. The structure of the magnet can meet the application of a conventional chip and can also meet the application of a chip in a mode of resisting stray difference.

There are many methods for increasing the strength of the middle portion of the magnet, and preferably, the thickness of the middle portion of the magnet is greater than the thickness of the magnets on both sides. Two thicker magnets can be added between the two original magnets, so that the magnetic field intensity in the middle of the whole magnet structure is improved, and the requirement of one-way linearity is met.

Preferably, the magnets comprise a first magnet and a second magnet which are integrally formed, the first magnet is close to one side of the PCB, the first magnet is in an isosceles triangle shape, the bottom edge of the first magnet is connected with the second magnet, and the second magnet is in a rectangular shape. The vertex angle of the first magnet is an obtuse angle. Simple structure can use the mode of anti stray field interference, and the precision reaches within 1%, can satisfy the demand in the technique.

Preferably, the magnets comprise two obliquely arranged magnets, the two magnets are in a splayed shape, and one ends of the two magnets close to each other face the PCB. The close end is just the upper end of the splayed shape, and the close end is closer to the PCB, so that the magnetic field intensity in the middle is stronger, and the requirement of linear angle change is met. Adopt two thin magnets simultaneously for the cost will be low, can also let the precision reach within 1% simultaneously, and the interference killing feature is strong.

Therefore, the utility model discloses an anti-interference displacement sensor possesses following advantage: the shape of the magnet can well ensure that the strength of the middle part of the magnet structure is high, so that the application in an anti-stray field is met, the differential magnetic field is unidirectional, the linear precision better conforms to an anti-stray differential formula, the anti-interference level of the sensor in a vehicle is improved, and more stable and reliable signals are output. The stability of the sensor is improved, the service life of the product is prolonged, and the failure information of the vehicle misjudgment sensor is reduced.

Drawings

Fig. 1 is a perspective view of a tamper resistant displacement sensor.

Fig. 2 is a front view of fig. 1.

FIG. 3 is a front view of embodiment 2.

Detailed Description

The technical solution of the present invention is further specifically described below by way of examples and with reference to the accompanying drawings.

Example 1:

as shown in fig. 1 and 2, the anti-interference displacement sensor comprises a sensor housing, wherein the sensor housing is made of nylon materials through injection molding. An embedded ring is installed at one end of the sensor shell, so that the sensor shell is conveniently fixed on the gearbox. A PCB is arranged in the sensor shell, a Hall sensor chip which is resistant to stray magnetic field interference is arranged on the PCB, and the model of the chip is a chip HAL 393X. A magnet structure is arranged on one side of the PCB, and the sensor shell moves transversely back and forth to cut magnetic lines of force and transmit magnetic field signals. The length of the magnet is related to the sensor displacement change, and the length of the magnet is similar to the sensor stroke length. The magnet structure comprises integrated into one piece's first magnet and second magnet, and first magnet is close to PCB board one side, and first magnet is isosceles triangle, and the apex angle of first magnet is the obtuse angle. The second magnet is arranged on one side of the bottom edge of the first magnet, and the second magnet is rectangular.

Example 2:

as shown in fig. 3, the magnet structure includes two elongated magnets having the same shape and size, unlike embodiment 1. Two magnets are obliquely arranged, the two magnets are arranged in a splayed shape, and one ends, connected with each other, of the two magnets face the PCB.

Claims

1. The utility model provides an anti-interference displacement sensor, includes sensor housing, installs the PCB board in sensor housing, its characterized in that: the Hall sensor chip of anti miscellaneous scattered magnetic field interference of installation on the PCB board is equipped with magnet in one side of PCB board, the magnetic field intensity at magnet middle part be greater than the magnetic field intensity of magnet both sides, the magnetic field angle is single-way change along with the displacement, the magnetic field angle change is linear.

2. A tamper resistant displacement sensor according to claim 1, further comprising: the thickness of the middle part of the magnet is larger than that of the magnets at two sides.

3. A tamper resistant displacement sensor according to claim 1, further comprising: the magnet include integrated into one piece's first magnet and second magnet, first magnet is close to PCB board one side, first magnet is isosceles triangle, the base and the second magnet of first magnet meet, the second magnet is the rectangle.

4. A tamper resistant displacement sensor according to claim 3, wherein: the vertex angle of the first magnet is an obtuse angle.

5. A tamper resistant displacement sensor according to claim 1, further comprising: the magnets comprise two obliquely arranged magnets, the two magnets are in a splayed shape, and one ends of the two magnets close to each other face the PCB.