Hall proximity switch with adjustable sensing distance
By introducing a code disk and a magnetic shielding component into the Hall effect proximity switch, the sensing direction of the Hall magnetic sensing device is changed, thus solving the problem of fixed sensing distance in traditional Hall effect proximity switches and realizing flexible adjustment and precise control of the sensing distance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-28
- Publication Date
- 2026-03-10
AI Technical Summary
Traditional Hall effect proximity switches have a fixed sensing distance, which cannot be adjusted according to different usage needs, and their application scenarios are limited, requiring them to be used with magnets of specific specifications.
The system employs a Hall effect magnetic sensor, a code disk, and a magnetic shielding assembly. By rotating the code disk, the sensing direction of the Hall effect magnetic sensor is changed, and the magnetic shielding assembly blocks magnetic field interference from other directions, thereby achieving adjustment of the sensing distance.
It enables flexible adjustment of the sensing distance of the Hall effect proximity switch, adapting to different magnetic field strengths and scenario requirements, thus improving the flexibility and accuracy of the application.
Smart Images
Figure CN223987088U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of magnetic proximity switch technology, and in particular to a Hall effect proximity switch with adjustable sensing distance. Background Technology
[0002] Hall effect proximity switches utilize the Hall effect to detect changes in external magnetic fields. By detecting the proximity of an object (usually a magnetic material), a corresponding switching signal is generated. Existing Hall effect proximity switches typically employ Hall sensors with fixed sensitivity and detect magnetic field induction based on their calibrated threshold values. When an external magnet approaches, the proximity switch generates a switching signal based on the change in magnetic field strength. However, this traditional design has the following problems:
[0003] 1. Fixed sensing distance: The sensitivity of the magnetic sensing element (such as a Hall sensor) in a traditional Hall effect proximity switch is fixed, and its sensing distance mainly depends on the calibration parameters of the sensor itself and the field strength of the magnet used. This means that users cannot adjust the sensing distance according to different usage needs, limiting the flexibility of the application.
[0004] 2. Limited application scenarios: Traditional Hall effect proximity switches typically require the use of magnets of specific specifications to ensure that the sensing distance is within the expected range. When the size, shape, or material of the magnet changes, the sensing distance also changes, making it difficult to adapt to different needs in diverse application scenarios and requiring additional configuration and adjustments. Utility Model Content
[0005] In order to achieve the goal of adjusting the sensing distance of the Hall effect proximity switch not only when using the same sensing ferromagnet, but also when using sensing magnets with different magnetic field strengths, thereby improving the flexibility of Hall effect proximity switch applications, this application provides a Hall effect proximity switch with adjustable sensing distance.
[0006] The Hall effect proximity switch with adjustable sensing distance provided in this application adopts the following technical solution:
[0007] A Hall effect proximity switch with adjustable sensing distance includes a Hall magnetic sensor, a code disk, and a magnetic shielding assembly. The Hall magnetic sensor is mounted on the code disk, and the bias current direction of the Hall magnetic sensor is always parallel to the code disk. The magnetic shielding assembly is disposed adjacent to the Hall magnetic sensor and is used to isolate magnetic field interference in non-sensing directions.
[0008] By adopting the above technical solution, the sensing direction of the Hall magnetic induction device can be changed by rotating the code disk, so that the intensity of the induced magnetic field on the sensing surface of the Hall magnetic induction device is the component of the original induced magnetic field. The magnetic shielding component is used to shield magnetic fields in other directions, so that the signal can be output accurately.
[0009] In practical applications, if it is necessary to adjust the Hall effect proximity switch to achieve different sensing distances for the same magnetic field strength, or to adjust the Hall effect proximity switch to achieve the same sensing distance for different magnetic field strengths, simply rotate the code disk to deflect the sensing surface of the Hall magnetic sensing device to a suitable angle, thereby improving the flexibility of Hall effect proximity switch applications.
[0010] Optionally, the Hall magnetic induction device is perpendicular to the center line of the code disk and collinear with the central axis of the code disk.
[0011] By adopting the above technical solution, the magnetic field components can be easily calculated in this positional relationship, that is, the magnetic field strength on the front of Hall is B*COSΦ (where B is the field strength of the original magnet on the front of Hall, and Φ is the rotation angle), thus facilitating the adjustment of the sensing distance.
[0012] Optionally, the magnetic shielding assembly includes two sets of isolation blocks, each having a magnetic shielding function. The Hall magnetic sensing device is located between the two sets of isolation blocks. The length of each isolation block is greater than the length of the Hall magnetic sensing device, and the height of each isolation block is greater than the height of the Hall magnetic sensing device. The relative direction of the two sets of isolation blocks is perpendicular to the direction of the induced magnetic field.
[0013] By adopting the above technical solution, the Hall magnetic sensing device can more accurately sense the magnetic field from the main direction, improve the overall sensing accuracy, and reduce the uncertainty caused by changes in the surrounding magnetic field.
[0014] Optionally, the isolation block is a rectangular block, and the length direction of the isolation block is parallel to the direction of the induced magnetic field.
[0015] Optionally, the material of the isolation block may be permalloy.
[0016] Optionally, the material of the isolation block can be soft iron / MU metal / iron-nickel alloy / silicon steel.
[0017] Optionally, it also includes a dial, which is coaxial with the code disk and can rotate relative to it. The code disk is provided with an indicator arrow.
[0018] By adopting the above technical solution, it is convenient to manually and accurately rotate the deflection angle of the Hall magnetic induction device.
[0019] Optionally, the direction of the indicator arrow is parallel to the direction of the bias current of the Hall magnetic sensor. When the direction of the bias current of the Hall magnetic sensor is perpendicular to the direction of the induced magnetic field, the indicator arrow points to the 0° mark of the dial. When the direction of the bias current of the Hall magnetic sensor is parallel to the direction of the induced magnetic field, the indicator arrow points to the 90° mark of the dial.
[0020] By adopting the above technical solution, a value such as (B, 0) corresponding to (0°, 90°) can be obtained. This clearly correlates the 0° and 90° angles with the change in magnetic field strength (from B to 0), allowing users to quantitatively control the sensitivity of the sensing device. For example, when rotated to 0°, the Hall magnetic sensor experiences the maximum magnetic field strength B, reaching its highest sensitivity; while when rotated to 90°, the induced magnetic field strength is 0, meaning the Hall device no longer senses a magnetic field. Therefore, users can select the appropriate sensing distance and sensitivity for different situations based on this clear numerical relationship, ensuring the device is adjusted as needed and avoiding blind adjustments. Furthermore, rotating to the corresponding 90° angle can also be used to turn off the Hall proximity switch in practical applications.
[0021] In summary, this application includes at least one of the following beneficial technical effects:
[0022] 1. By rotating the code disk, the sensing direction of the Hall magnetic induction device can be changed, so that the intensity of the induced magnetic field on the sensing surface of the Hall magnetic induction device is the component of the original induced magnetic field. The magnetic shielding component is used to shield magnetic fields in other directions, so that the signal can be output accurately.
[0023] Therefore, in practical applications, if it is necessary to adjust the Hall effect proximity switch to achieve different sensing distances for the same magnetic field strength, or to adjust the Hall effect proximity switch to achieve the same sensing distance for different magnetic field strengths, it is only necessary to rotate the code disk to deflect the sensing surface of the Hall effect magnetic sensing device to a suitable angle, thereby improving the flexibility of Hall effect proximity switch applications.
[0024] 2. The Hall magnetic induction device is perpendicular to the center line of the code disk and collinear with the central axis of the code disk. In this positional relationship, it is convenient to calculate the magnetic field components, that is, the magnetic field strength on the front of the Hall is B*COSΦ (where B is the field strength of the original magnet on the front of the Hall and Φ is the rotation angle), thus facilitating the adjustment of the sensing distance.
[0025] 3. By explicitly mapping the 0° and 90° angles to changes in magnetic field strength (from B to 0), users can quantitatively control the sensitivity of the sensing device. Based on this clear numerical relationship, users can select the appropriate sensing distance and sensitivity for different situations, ensuring that the device is adjusted as needed and avoiding blind adjustments. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application.
[0027] Figure 2 This is a schematic diagram illustrating the structure of the dial and the indicator arrow in an embodiment of this application.
[0028] Explanation of reference numerals in the attached diagram: 1. Hall effect magnetic sensor; 2. Code disk; 21. Indicating arrow; 3. Magnetic shielding assembly; 31. Isolation block; 4. Scale. Detailed Implementation
[0029] The following is in conjunction with the appendix Figure 1-2 This application will be described in further detail.
[0030] This application discloses a Hall effect proximity switch with adjustable sensing distance.
[0031] like Figure 1 The Hall effect proximity switch with adjustable sensing distance includes a Hall magnetic sensor 1, a code disk 2, and a magnetic shielding component 3. The Hall magnetic sensor 1 is mounted on the code disk 2, and the bias current direction of the Hall magnetic sensor 1 is always parallel to the code disk 2. The magnetic shielding component 3 is located close to the Hall magnetic sensor 1 and is used to isolate magnetic field interference in the non-sensing direction.
[0032] The Hall magnetic sensor 1 can be a silicon semiconductor board or a semiconductor board made of other materials (such as germanium / gallium arsenide). The semiconductor board is provided with a current input terminal, a current output terminal, a ground terminal, a Hall voltage output terminal, and a reference voltage terminal. The Hall magnetic sensor 1 is perpendicular to the center line of the code disk 2 and collinear with the central axis of the code disk 2.
[0033] In other embodiments, the Hall magnetic sensing device 1 can be set off-center from the code disk 2, perpendicular to the center line of the code disk 2. This design allows the Hall proximity switch to be applied to sensing magnets with a wider range of magnetic induction intensities.
[0034] The magnetic shielding component 3 consists of two sets of isolation blocks 31. In this embodiment, each set of isolation blocks 31 has one block. In other embodiments, the number of isolation blocks 31 can be two or more, and the same set of isolation blocks 31 are stacked.
[0035] The material of the isolation block 31 can be permalloy / MU metal / iron-nickel alloy / silicon steel. In this embodiment, the material of the isolation block 31 is permalloy.
[0036] In this embodiment, the isolation block 31 is a rectangular block. The Hall magnetic sensor 1 and the code disk 2 are both located between two isolation blocks 31. The length of the isolation block 31 is greater than the length of the Hall magnetic sensor, and the height of the isolation block 31 is greater than the height of the Hall magnetic sensor 1. The relative direction of the isolation block 31 is perpendicular to the direction of the induced magnetic field; that is, in this embodiment, the length direction of the isolation block 31 is parallel to the direction of the induced magnetic field. In other embodiments, the isolation block 31 may also be an arc-shaped block.
[0037] like Figure 2 The Hall effect proximity switch also includes a scale 4, which is coaxial with the code disk 2 and can rotate relative to it. The scale 4 is coaxially arranged on its outer periphery, and the code disk 2 has an indicator arrow 21. In this embodiment, the scale 4 and the code disk 2 are coplanar, and the direction of the indicator arrow 21 is parallel to the bias current direction of the Hall magnetic sensor 1. When the bias current direction of the Hall magnetic sensor 1 is perpendicular to the direction of the induced magnetic field, the indicator arrow 21 points to the 0° mark on the scale 4; when the bias current direction of the Hall magnetic sensor 1 is parallel to the direction of the induced magnetic field, the indicator arrow 21 points to the 90° mark on the scale 4. In other embodiments, a lever can be connected to the code disk 2, and two limit blocks can be installed inside the housing of the Hall effect proximity switch to restrict the code disk 2 to rotate only in a clockwise direction from 0° to 90°.
[0038] In other embodiments, the dial 4 can be fixed to the outer surface of the housing of the Hall effect proximity switch, and the code disk 2 can be coaxially connected to a knob with an indicator arrow 21, the knob being rotatably connected to the housing of the Hall effect proximity switch.
[0039] In practical use, the output, input and ground terminals of Hall magnetic sensing device 1 can be connected to corresponding components (such as external interfaces, capacitors and amplifiers) through slip rings / flexible cables / rotary joints, etc., to avoid the Hall magnetic sensing device 1 being pulled or twisted when rotating, which would affect the service life of the proximity switch.
[0040] The implementation principle of this application embodiment is as follows: by rotating the code disk 2, the sensing direction of the Hall magnetic induction device 1 can be changed, so that the intensity of the induced magnetic field on the sensing surface of the Hall magnetic induction device 1 is the component of the original induced magnetic field. The magnetic shielding component 3 is used to shield magnetic fields in other directions, so that the signal can be accurately output.
[0041] In practical applications, if it is necessary to adjust the Hall effect proximity switch to achieve different sensing distances for the same magnetic field strength, or to adjust the Hall effect proximity switch to achieve the same sensing distance for different magnetic field strengths, simply rotate the code disk 2 to deflect the sensing surface of the Hall magnetic sensing device 1 to a suitable angle, thereby improving the flexibility of Hall effect proximity switch applications.
[0042] The specific operation can be performed by manually adjusting and testing multiple times, or it can be based on a formula.
[0043]
[0044] Where d is the distance between the magnet and the Hall sensor;
[0045] B threshold It is the sensing threshold;
[0046] μ0 is the free permeability (a constant, approximately equal to 4π·10⁻⁶). -7 N / A 2 );
[0047] M is the magnetic moment of the magnet, which is related to the magnet's material and volume;
[0048] Φ is the rotation angle.
[0049] When using the same magnet and setting the proximity switch to have different sensing distances for that magnet, the Φ value can be obtained by using the preset sensing distance value, combining the relevant data of the magnet, and substituting it into the formula. At this time, the turntable encoder 2 can deflect the Hall magnetic sensor 1 to the corresponding angle (Φ value).
[0050] When using magnets with different magnetic field strengths, and to ensure that the proximity switch has the same sensing distance for all magnets, the Φ value can also be obtained according to the above operation. At this time, the turntable encoder 2 can deflect the Hall magnetic induction device 1 to the corresponding angle (Φ value).
[0051] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.
Claims
1. An inductively distance-adjustable Hall effect proximity switch, characterized in that: The application relates to a Hall magnetic induction device (1), a code disc (2) and a magnetic shielding assembly (3), wherein the Hall magnetic induction device (1) is installed on the code disc (2), the bias current direction of the Hall magnetic induction device (1) is always parallel to the code disc (2), and the magnetic shielding assembly (3) is arranged near the Hall magnetic induction device (1) and is used for isolating magnetic field interference in a non-induction direction.
2. The inductively distance adjustable Hall effect proximity switch of claim 1, wherein: The Hall magnetic induction device (1) is perpendicular to the center line of the code disc (2) and is collinear with the central axis of the code disc (2).
3. The inductively distance adjustable Hall effect proximity switch of claim 1, wherein: The magnetic shielding assembly (3) comprises two groups of isolation blocks (31) having a magnetic shielding function, the Hall magnetic induction device (1) is located between the two groups of isolation blocks (31), the length of the isolation blocks (31) is greater than that of the Hall magnetic induction device (1), the height of the isolation blocks (31) is greater than that of the Hall magnetic induction device (1), and the relative direction of the two groups of isolation blocks (31) is perpendicular to the direction of the induction magnetic field.
4. The inductively distance adjustable Hall effect proximity switch of claim 3, wherein: The isolation blocks (31) are rectangular blocks, and the length direction of the isolation blocks (31) is parallel to the direction of the induction magnetic field.
5. A Hall effect proximity switch with adjustable sensing distance according to any of claims 3 or 4, characterized in that: The material of the isolation blocks (31) can be permalloy.
6. A Hall effect proximity switch with adjustable sensing distance according to any of claims 3 or 4, characterized in that: The material of the isolation blocks (31) can be soft iron, MU metal, iron-nickel alloy or silicon steel.
7. The inductively distance adjustable Hall effect proximity switch of claim 2, wherein: The application further comprises a scale disc (4) coaxial with the code disc (2), the scale disc (4) can rotate relative to the code disc (2), and the code disc (2) is provided with an indicating arrow (21).
8. The inductively distance adjustable Hall effect proximity switch of claim 7, wherein: The direction of the indicating arrow (21) is parallel to the bias current direction of the Hall magnetic induction device (1), when the bias current direction of the Hall magnetic induction device (1) is perpendicular to the direction of the induction magnetic field, the indicating arrow (21) points to the 0-degree scale of the scale disc (4), and when the bias current direction of the Hall magnetic induction device (1) is parallel to the direction of the induction magnetic field, the indicating arrow (21) points to the 90-degree scale of the scale disc (4).