Anti-interference dual-redundancy magnetic shielding inductive proximity sensor and debugging method

Abstract

This invention discloses an anti-interference dual-redundant magnetically shielded inductive proximity sensor and its debugging method, relating to the field of inductive proximity sensor technology. To address the problems of signal interference when sensors are installed at close range in existing technologies, and the poor anti-interference performance and complex assembly and debugging of existing dual-redundant products, the following technical solution is proposed: An anti-interference dual-redundant magnetically shielded inductive proximity sensor includes an eddy current isolation plate, a support plate, a housing, a top cover plate, and two sets of identical and independent sensing elements. Each sensing element includes a coil winding, a core inserted into the coil winding, a magnetic shielding cover fitted around the coil winding and the core, and notches at both ends of the magnetic shielding cover. A support base is also provided for fixing the coil winding and the magnetic shielding cover. This invention uses a magnetic shielding cover and an eddy current isolation plate to effectively isolate the dual-redundant signal from external environmental interference, while reducing the complexity of assembly and debugging.

Description

Technical Field

[0001] This invention relates to the field of inductive proximity sensor technology, specifically to an anti-interference dual-redundant magnetically shielded inductive proximity sensor and its debugging method. Background Technology

[0002] Proximity sensors can be categorized by principle into inductive, eddy current, capacitive, and Hall effect proximity sensors. Inductive proximity sensors utilize the self-inductance of a coil and the change in mutual inductance between coils in the electromagnetic induction phenomenon to achieve measurement. The basic working principle of an inductive proximity sensor is that when the measured metal object moves, the air gap between the sensor's sensitive element and the metal object changes, causing a change in magnetic resistance, which in turn causes a change in the coil's inductance. This change in inductance corresponds to the change in the measured object's position, thus achieving non-contact measurement.

[0003] With technological advancements, inductive proximity sensors are finding increasingly widespread applications in the aviation industry. Due to the high safety and reliability requirements of aviation, multiple redundant measurements are needed to comprehensively assess the same object at a given location, ensuring both high reliability and safety. Space constraints in aviation necessitate the installation of two or more inductive proximity sensors within limited areas, resulting in close proximity. This close proximity can lead to mutual inductance oscillations and unstable output. Therefore, a small, independent, and interference-free dual-redundant inductive proximity sensor is needed. Since inductive proximity sensors primarily utilize electromagnetic induction, they may fail or malfunction in environments with magnetic metals. Therefore, in applications requiring high accuracy or where the sensor is surrounded by metallic objects, an inductive proximity sensor resistant to environmental interference is required.

[0004] Currently, existing dual-redundant inductive proximity sensors can only achieve two independent signals without interference, which has poor resistance to environmental interference and is too complicated to assemble and debug in engineering applications. Therefore, a design and debugging method for an engineered, small-sized, high-sensitivity, environmentally resistant, dual-redundant magnetically shielded inductive proximity sensor is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide an anti-interference dual-redundant magnetically shielded inductive proximity sensor to solve the problems of mutual signal interference and susceptibility to the influence of the surrounding metal environment when the sensor is installed at close range in the prior art, as well as the poor anti-interference performance and complex assembly and debugging of existing dual-redundant products.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows:

[0007] An anti-interference dual-redundant magnetically shielded inductive proximity sensor includes an eddy current isolation plate, a support plate, a housing, a top cover plate, and two sets of identical and independent sensing elements. Each sensing element includes a coil winding, a core inserted into the coil winding, and a magnetic shield fitted around the coil winding and core. The magnetic shield has notches at both ends, and a support base for fixing the coil winding and the magnetic shield. The eddy current isolation plate is positioned between the two sensing elements. The support plate is connected to the core with screws, fixing the sensing element inside the housing. The top cover plate is welded and sealed to the housing. The sensor also includes a connector for external electrical connection. The two sets of sensing elements are arranged at a 90° angle inside the housing to achieve dual-redundant independent output without interference.

[0008] Furthermore, the magnetic shield is made of a high magnetic permeability material, and the notches at both ends correspond to the arched notches of the support base.

[0009] Furthermore, the eddy current isolation plate has a cuboid structure and is vertically inserted between the two sets of sensitive elements.

[0010] Furthermore, the outer shell, top cover, and connector are made of stainless steel 022Cr17Ni12Mo2 material and are formed into a sealed structure by laser welding.

[0011] Furthermore, the assembly gap between the coil winding and the core, the notch size of the magnetic shield, and the insertion position of the eddy current isolation plate are key debugging parameters. By adjusting these parameters, the sensor's high sensitivity and anti-interference performance can be achieved.

[0012] A debugging method for an anti-interference dual-redundant magnetically shielded inductive proximity sensor includes the following steps:

[0013] S1: Insert the coil winding into the core and adjust the core insertion depth to set the initial inductance value;

[0014] S2: Install the components from S1 into the support base and magnetic shield, ensuring that the notch in the magnetic shield is aligned with the arched notch in the support base;

[0015] S3: Install the two sets of sensitive elements inside the housing at a 90° angle;

[0016] S4: Insert the eddy current isolation plate between the two sets of sensitive elements;

[0017] S5: Secure the sensitive element with a support plate and screws, and weld the support plate to the housing;

[0018] S6: Fill the internal voids with DG-4 silicone;

[0019] S7: Laser weld the top cover to the housing to seal it, and then solder the leads into the corresponding pins of the connector.

[0020] Furthermore, in S3, the 90° arrangement of the two sets of sensitive elements is achieved through a positioning structure inside the housing.

[0021] Furthermore, in S6, the DG-4 silicone potting material must completely fill the gap between the sensitive element and the housing.

[0022] The present invention has the following beneficial effects:

[0023] 1. Ability to resist interference from the surrounding environment; This invention designs a magnetic shield and an eddy current isolation plate, which not only isolates the signals of the two redundant inductors, but also achieves anti-interference design against the surrounding environment while ensuring high sensitivity.

[0024] 2. Engineering design: This invention only designs a magnetic shield and a cuboid eddy current isolation plate on each redundancy, reducing debugging steps and complex assembly. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the device structure of the present invention;

[0026] Figure 2 This is a schematic diagram of the sensor principle of the present invention;

[0027] Figure 3 This is a schematic diagram of the sensor structure of the present invention;

[0028] Figure 4 This is a schematic diagram of the sensor connector installation according to the present invention;

[0029] Figure 5 This is a schematic diagram showing the installation of the magnetic shielding cover and the sensitive element of the present invention;

[0030] Figure 6 This is a schematic diagram of the magnetic shielding cover structure of the present invention;

[0031] Figure 7 This is a flowchart of the debugging process for this invention.

[0032] Figures 1 to 7 The reference numerals in the attached drawings are respectively: 1-coil winding, 2-core, 3-support base, 4-magnetic shield, 5-eddy current isolation plate, 6-support plate, 7-outer shell, 8-upper cover plate, 9-connector. Detailed Implementation

[0033] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] An anti-interference dual-redundant magnetically shielded inductive proximity sensor is disclosed in this embodiment. The sensor body consists of a housing 7, a top cover 8, and a connector 9. The housing 7, top cover 8, and connector 9 are preferably made of stainless steel 022Cr17Ni12Mo2 and are sealed together using laser welding to form a robust and reliable sealed structure. The connector 9 is used to achieve the overall electrical connection of the sensor to the outside.

[0035] like Figure 1 , 3 As shown in Figure 4, the present invention mainly includes two sets of sensing elements with the same structure and independent of each other, and an eddy current isolation plate 5 for isolating the two sets of sensing elements.

[0036] Each sensitive element consists of a coil winding 1, a core 2, a support base 3, and a magnetic shield 4. The assembly relationship is as follows: the core 2 is inserted into the coil winding 1, and the "coil-core" assembly is then installed in the support base 3, with the magnetic shield 4 covering its outer periphery.

[0037] like Figure 2 As shown, the working principle of this sensor is as follows: when current flows through coil winding 1, a magnetic field is generated, and the coil in the magnetic field generates inductance. The magnitude of the inductance is affected by the magnetic reluctance of the magnetic circuit in which it is located. This magnetic circuit consists of the iron core, the target, and the air gap between them. When the air gap changes, the magnetic reluctance changes accordingly, thereby causing a change in the output inductance of the coil, thus realizing non-contact measurement.

[0038] like Figure 5 , 6 As shown, to address the issues of internal interference and external environmental interference in the dual-redundancy design, the following design was adopted:

[0039] The two sets of sensing elements are arranged at a 90° angle inside the housing 7. This is intended to prevent magnetic flux linkage between the two sets of elements and is one of the core measures to achieve independent and non-interfering dual-redundancy signals.

[0040] Then, a rectangular eddy current isolation plate 5 is vertically inserted between the two sets of sensitive elements arranged at 90°. This isolation plate is used to further isolate the magnetic field coupling that may exist between the two sets of elements, thereby enhancing the independence of the signal.

[0041] Finally, each sensing element is equipped with a magnetic shield 4. This magnetic shield 4 is preferably made of a high-permeability material, which not only effectively shields against environmental interference from surrounding metal objects or electromagnetic fields, but also provides internal isolation for the inductive signals of the two redundancies. To ensure high sensitivity, the magnetic shield 4 has notches at both ends, and the positions of these notches must correspond to the arched notches of the support base 3.

[0042] In addition, the assembly gap between the coil winding 1 and the core 2, the notch size of the magnetic shield 4, and the insertion position of the eddy current isolation plate 5 are key debugging parameters for achieving high sensitivity and strong anti-interference performance of the sensor.

[0043] As attached Figure 7 As shown, the present invention also provides a debugging method based on the above-mentioned sensor, specifically including the following steps:

[0044] S1: Insert the coil winding 1 into the core 2, and set and adjust the initial inductance value of the product by adjusting the insertion depth of the core 2.

[0045] S2: Install the components completed in step S1 into the support base 3 and the magnetic shield 4 to form a complete sensing element. In this step, it is essential to ensure that the notch in the magnetic shield 4 is aligned with the arched notch in the support base 3.

[0046] S3: The two sets of prepared sensitive elements are installed in the housing 7 at a 90° angle. This 90° arrangement is achieved through the positioning structure inside the housing 7 to ensure the accuracy of the angle.

[0047] S4: Insert the eddy current isolation plate 5 into the housing 7 and place it between the two sets of sensitive elements.

[0048] S5: The sensitive element is fixed by the support plate 6 and screws. Specifically, the support plate 6 and the outer shell 7 are welded together to form a reinforcing rib, and then screws are inserted into the support plate 6 to connect it to the core 2 of the sensitive element, thereby firmly fixing it.

[0049] S6: Use DG-4 silicone to fill the internal gaps. The filling material must completely fill the gap between the sensitive element and the outer shell 7 to achieve fixation, vibration reduction and protection.

[0050] S7: Seal the top cover plate 8 and the housing 7 using laser welding, and weld the coil leads to the corresponding pins of the connector 9. Finally, weld the connector 9 to the entire assembly to complete the final encapsulation.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An anti-interference dual-redundant magnetically shielded inductive proximity sensor, characterized in that, The system includes an eddy current isolation plate (5), a support plate (6), a housing (7), a top cover plate (8), and two sets of identical and independent sensitive elements. Each sensitive element includes a coil winding (1) and a core (2). The core is inserted into the coil winding (1). A magnetic shield (4) is fitted around the coil winding (1) and the core (2). The magnetic shield (4) has notches at both ends and a support base for fixing the coil winding (1) and the magnetic shield (4). The eddy current isolation plate (5) The support plate (6) is located between the two sets of sensitive elements. The support plate (6) is connected to the core (2) by screws to fix the sensitive elements in the housing (7). The upper cover plate (8) is welded and sealed to the housing (7). It also includes a connector (9) for realizing the external electrical connection of the sensor. The two sets of sensitive elements are arranged at a 90° angle in the housing (7) to realize dual redundancy independent output and mutual non-interference. The eddy current isolation plate (5) is a cuboid structure and is vertically inserted between the two sets of sensitive elements.

2. The anti-interference dual-redundant magnetically shielded inductive proximity sensor according to claim 1, characterized in that, The magnetic shield (4) is made of a high magnetic permeability material, and the positions of its two end notches correspond to the arched notches of the support base (3).

3. The anti-interference dual-redundant magnetically shielded inductive proximity sensor according to claim 1, characterized in that, The outer shell (7), the upper cover plate (8) and the connector (9) are made of stainless steel 022Cr17Ni12Mo2 material and are formed into a sealed structure by laser welding.

4. The anti-interference dual-redundant magnetically shielded inductive proximity sensor according to claim 1, characterized in that, The assembly gap between the coil winding (1) and the core (2), the notch size of the magnetic shield (4), and the insertion position of the eddy current isolation plate (5) are key debugging parameters. By adjusting the above parameters, the high sensitivity and anti-interference performance of the sensor can be achieved.

5. A debugging method for an anti-interference dual-redundant magnetically shielded inductive proximity sensor, characterized in that, Based on the anti-interference dual-redundant magnetically shielded inductive proximity sensor according to any one of claims 1-4, the following steps are included: S1: Insert the coil winding (1) into the core (2) and adjust the insertion depth of the core (2) to set the initial inductance value; S2: Install the components in S1 into the support base (3) and the magnetic shield (4), ensuring that the notch of the magnetic shield (4) is aligned with the arched notch of the support base (3); S3: Install the two sets of sensitive elements at a 90° angle inside the housing (7); S4: Insert the eddy current isolation plate (5) between the two sets of sensitive elements; S5: Fix the sensitive element by means of the support plate (6) and screws, and weld the support plate (6) to the housing (7); S6: Fill the internal voids with DG-4 silicone; S7: Laser weld the top cover (8) to the outer shell (7) to seal, and solder the lead wires into the corresponding pins of the connector (9).

6. The debugging method for an anti-interference dual-redundant magnetically shielded inductive proximity sensor according to claim 5, characterized in that, In S3, the 90° arrangement of the two sets of sensitive elements is achieved through the positioning structure inside the housing (7).

7. The debugging method for an anti-interference dual-redundant magnetically shielded inductive proximity sensor according to claim 5, characterized in that, In S6, the DG-4 silicone potting material must completely fill the gap between the sensitive element and the housing (7).

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