CN215447744U

CN215447744U - Brake stroke sensor structure

Info

Publication number: CN215447744U
Application number: CN202121938136.9U
Authority: CN
Inventors: 洪伟
Original assignee: Zhejiang Woder Technology Group Co ltd
Current assignee: Zhejiang Woder Technology Group Co ltd
Priority date: 2021-01-29
Filing date: 2021-08-18
Publication date: 2022-01-07
Anticipated expiration: 2031-08-18

Abstract

The present invention relates to a sensor. A brake stroke sensor structure comprises a sensor and a magnet fixing structure positioned on one side of the sensor, wherein the sensor comprises a sensor shell, a PCB (printed circuit board) and an external connector are arranged in the sensor shell, and a 3D Hall chip is mounted on the PCB; the magnet fixing structure comprises a shell, at least one group of magnet group is arranged in the shell, and the magnet group comprises two magnets which are connected with each other in the same pole. The utility model provides a brake stroke sensor structure which has small volume, strong anti-interference capability and good brake control accuracy on long stroke; the technical problems that the sensor in the long-stroke brake system is large in structure size, poor in anti-interference capability and insufficient in control precision in the prior art are solved.

Description

Brake stroke sensor structure

Technical Field

The utility model relates to a sensor, in particular to a long-stroke sensor structure.

Background

The popularization of automobile application improves the convenience of life of people. With the improvement of the quality of life, people have more and more requirements on automobiles. There is also a higher demand for brake systems as important parts of automobiles.

In a whole vehicle system, if the monitoring requirement is met on the brake stroke, a sensor is usually arranged to realize the monitoring.

The scheme on the market realizes monitoring through the principle of electromagnetism or 3D hall, if use electromagnetic induction, sensor size often with the brake stroke unanimous or similar, if use 3D hall, the excitation source-magnet if not design into the magnet that the brake stroke is the same or longer magnet often the product can be very poor at the anti dry fishing ability of extreme position.

Disclosure of Invention

The utility model provides a brake stroke sensor structure which has small volume, strong anti-interference capability and good brake control accuracy on long stroke; the technical problems that the sensor in the long-stroke brake system is large in structure size, poor in anti-interference capability and insufficient in control precision in the prior art are solved.

The technical problem of the utility model is solved by the following technical scheme: a brake stroke sensor structure comprises a sensor and a magnet fixing structure positioned on one side of the sensor, wherein the sensor comprises a sensor shell, a PCB (printed circuit board) and an external connector are arranged in the sensor shell, and a 3D Hall chip is mounted on the PCB; the magnet fixing structure comprises a shell, at least one group of magnet group is arranged in the shell, and the magnet group comprises two magnets which are connected with each other in the same pole.

The magnet fixing structure is driven by a push rod of a brake system to move axially, the magnet group is driven by the push rod to move, the magnet group is in a working area, and signals output by the sensor are linear curves. The mode that magnet homopolar offset was arranged is adopted, 2 side magnetic circuits are sparse, the intensive magnetic field environment of middle magnetic circuit, the 3D hall response chip of the anti-interference mode of cooperation sensor, to the within range of work area threshold value W, the angle is one-way change, can obtain linear output curve through linearization calibration, and to the extension region, the angle that also is between threshold value W and the stroke limit value can exceed 360, the output can be changed from high clamp to low clamp, through weak magnetic diagnosis, set up diagnostic output to be unanimous with high clamp output, with this reach when normal work with conventional position sensor unanimous, when the stroke exceeded certain threshold value of settlement, can output a normal value and report to the police to system output. Due to the unique magnetic circuit distribution, the anti-interference capability of the travel limit position is not influenced by the nearby environment under the condition of ensuring the high precision of the sensor.

According to the different intensity of two magnets, can design different magnet installation modes, one of them mounting means is: two cavities on the same axis are formed in the shell in an injection molding mode, the two magnets are installed in the two cavities respectively, and then the cover plate is installed on the cavities to fix the two magnets.

The other installation mode is as follows: the two magnets in the shell and the outer sleeve are integrally formed in an injection molding mode.

Still another installation method is: one of the magnets in the magnet group is arranged in a cavity on the shell, a cover plate is arranged on the cavity, and the other magnet on one side of the cavity and the shell are integrally formed to form a magnet. A magnet and the integrative injection moulding of casing, magnet are wrapped up by the casing, and another magnet is follow-up installs in the fashioned cavity of casing.

Preferably, the two magnets in the housing are coaxially arranged up and down, and the movement direction of the magnets is parallel to one of the three-axis magnetic fields of the 3D Hall chip and is on the same plane. The chip can be fine response magnetic field intensity's change, prevents angle error.

Preferably, an arc-shaped cavity is formed in the shell, the magnet is mounted in the cavity, an arc-shaped stop surface extends outwards from the inner wall of the cavity, and the radian of the stop surface is the same as that of the outer circumferential surface of the magnet. The stop surface has certain elasticity, and when the magnet is installed in the cavity, a force towards the cavity is applied to the magnet through the arc-shaped stop surface so as to balance the magnetic force with homopolar repulsion. Helping the magnet to be more effectively fixed in the cavity.

Preferably, the outer surface of the housing of the magnet fixing structure is provided with an anti-rotation surface. After the magnet structure and the brake structure are installed, the magnet structure cannot rotate, and therefore the accuracy of the sensor is guaranteed.

Preferably, the external component in the sensor shell is a pin or a spring structure. The connection mode of the sensor shell can be changed as required, the stitch connection and the elastic sheet connection can be realized, and the adaptability is strong.

Therefore, the brake stroke sensor structure provided by the utility model has the following advantages: the magnet is small in size, convenient to install and arrange, capable of effectively reducing cost and saving space; two magnets which are oppositely arranged in the same pole are matched with the 3D Hall chip, so that the linearization of sensor signals is guaranteed, the accuracy of forming control is improved, and the anti-interference capability of a product is improved.

Drawings

Fig. 1 is a schematic position diagram of a brake stroke sensor structure according to the present invention.

Fig. 2 is an exploded view of the sensor housing.

Fig. 3 is an exploded view of another sensor housing.

Fig. 4 is an exploded view of the magnet fixing structure of embodiment 2.

Fig. 5 is an exploded view of a magnet fixing structure of example 3.

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, a brake stroke sensor structure includes a sensor 30 and a magnet fixing structure 20 at one side of the sensor 5. The sensor 30 is located below the magnet mounting structure 20.

The magnet fixing structure 20 comprises a shell 1, two magnets with the same poles opposite and the same length are installed in the shell 1, and an upper magnet 2 and a lower magnet 3 are integrally injection-molded with the shell. The cross section of the shell 1 molded outside the magnet is in a cross shape. A raised anti-rotation surface 4 is formed on the housing 1 of the magnet.

As shown in fig. 2, the sensor 30 includes a sensor housing 5, and the sensor housing 5 has a Z-shape. A PCB 13 is installed in the upper horizontal cavity of the sensor housing 5, and a 3D hall sensing chip 14, the model of which is HAL _3930, is installed on the PCB 13. A pin 6 is mounted in the lower horizontal cavity of the sensor housing 5. The pin 6 is mounted in the sensor housing 5 by two film coatings 10 and then by two injection molding, and an insert ring 9 and a sealing ring 11 are also injection molded in the sensor housing 5. The pins 6, the PCB 13, the sealing ring 11 and the insert ring 9 are mounted in the sensor housing 5 and then encapsulated in the sensor housing 5 by the faceplate 12. A main positioning boss 8 is integrally formed in the axial direction of the pin mounting portion of the sensor housing 5, and a sub positioning boss 7 is further formed in the sensor housing 5, the position of the sub positioning boss 7 being perpendicular to the position of the main positioning boss 8.

Of course, the structure of the sensor may also be as shown in fig. 3, the pins are replaced by the elastic pieces 15, and when the sensor transmits signals, the elastic pieces 15 are abutted with external springs and other members, so as to transmit signals.

Example 2:

as shown in fig. 4, unlike embodiment 1, the magnet fixing structure 20 includes a housing 1, two cavities 18 are integrally formed in the housing 1, the cavities 18 are located on the same axis, the cross section of each cavity 18 is semicircular, an arc-shaped stop surface 17 extends outwards from both ends of the inner wall of each cavity 18, and the radian of each stop surface 17 is the same as that of the outer circumferential surface of the magnet. After the upper magnet 2 and the lower magnet 3 are fitted into the cavity 18, the two magnets are fixed to the cavity 18 by the cover plate 16 on the cavity 18, and then the cover plate 16 is fixed by hot riveting.

Example 3:

as shown in fig. 5, different from embodiment 1, the magnet fixing structure 20 includes a housing 1, two magnets which are positioned on the same axis and connected with the same pole are installed in the housing 1, wherein the upper magnet 2 and the housing are fixed in the housing 1 by integral injection molding, the lower magnet 3 is subsequently installed in a cavity 18 formed on the housing, the cross section of the cavity is semicircular, an arc-shaped stop surface 17 extends outwards from two ends of the inner wall of the cavity, and the radian of the stop surface is the same as that of the outer circumferential surface of the magnet. After the lower magnets are installed in the cavity, the two magnets are fixed in the cavity through the cover plate 16 on the cavity, and then the cover plate 16 is fixed through hot riveting.

Claims

1. A brake stroke sensor structure which is characterized in that: the sensor comprises a sensor and a magnet fixing structure positioned on one side of the sensor, wherein the sensor comprises a sensor shell, a PCB (printed circuit board) and an external piece are arranged in the sensor shell, and a 3D Hall chip is arranged on the PCB; the magnet fixing structure comprises a shell, at least one group of magnet group is arranged in the shell, and the magnet group comprises two magnets which are connected with each other in the same pole.

2. A brake stroke sensor structure according to claim 1, wherein: the shell in be equipped with two cavitys that are located same axis, two magnets are installed respectively in two cavitys, install the apron on the cavity.

3. A brake stroke sensor structure according to claim 1, wherein: the two magnets in the shell and the outer sleeve are integrally formed in an injection molding mode.

4. A brake stroke sensor structure according to claim 1, wherein: one of the magnets in the magnet group is arranged in a cavity on the shell, a cover plate is arranged on the cavity, and the other magnet on one side of the cavity and the shell are integrally formed to form a magnet.

5. The brake stroke sensor structure according to any one of claims 1 to 4, wherein: two magnets in the shell are coaxially arranged up and down, and the movement direction of the magnets is parallel to one of three-axis magnetic fields of the 3D Hall chip and is on the same plane.

6. The brake stroke sensor structure according to any one of claims 1 to 4, wherein: be equipped with curved cavity on the shell, install magnet in the cavity the inner wall of cavity outwards extend and have curved backstop face, the radian of backstop face is the same with the radian of the outer circumferential surface of magnet.

7. The brake stroke sensor structure according to any one of claims 1 to 4, wherein: the outer surface of the shell of the magnet fixing structure is provided with an anti-rotation surface.

8. The brake stroke sensor structure according to any one of claims 1 to 4, wherein: the external part in the sensor shell is in a pin or elastic sheet structure.