Inductive displacement sensor and manufacturing method thereof
The modular design and bonding method of the inductive displacement sensor solves the problem of winding inconsistency, improves production efficiency and measurement accuracy, reduces costs, and ensures the stability and accuracy of the sensor.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-02
- Publication Date
- 2026-03-31
AI Technical Summary
The existing structural design of inductive displacement sensors makes it difficult to uniformly control the winding density, inter-turn spacing, and layer distribution, resulting in substandard parameters, affecting measurement accuracy and signal linearity. Furthermore, the rework process is complex and may damage the core and coil.
The sensitive element adopts a modular design. The inductor coil is first wound and then placed in the receiving groove of the iron core and fixed by adhesive bonding to ensure the consistency of the number of turns and arrangement of the inductor coil, avoiding the inconsistency caused by direct radial winding. It is combined with epoxy resin adhesive bonding and heat shrink tubing to protect the leads.
This achieves consistency in inductor coil parameters, improves production efficiency and reduces costs, while ensuring measurement accuracy and reliability, and preventing sensor loosening or displacement during operation.
Smart Images
Figure CN121761733A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of inductive displacement sensor manufacturing technology, and more specifically, relates to an inductive displacement sensor and its manufacturing method. Background Technology
[0002] Existing inductive displacement sensors typically consist of two sets of unidirectional displacement measuring coils arranged in opposite directions, with the coils usually fabricated by directly winding them onto the surface of an iron core. This structural design and manufacturing method has significant technical limitations. During the winding process, it is difficult to achieve uniform control over the winding density, turn spacing, and layer distribution of the coils. If winding deviations occur, the parameters will not meet the standards, leading to problems such as linearity deviations in the sensor output signal and fluctuations in measurement accuracy. This requires the entire wound coil to be dismantled and reworked, which not only significantly increases labor time and costs but may also cause damage such as iron core deformation and coil frame breakage due to mechanical stress during the dismantling operation.
[0003] Based on this, the technical problem to be solved in this application is: how to solve the structural defects of inductive displacement sensors. Summary of the Invention
[0004] The main objective of this application is to provide an inductive displacement sensor and its manufacturing method. The sensing element of this inductive displacement sensor adopts a modular design, which, compared to traditional structures, avoids defects such as inconsistent winding arrangement and uneven parameters caused by direct radial winding on the iron core. Furthermore, this application also provides its manufacturing method, which ensures a tight fit between the inductor coil and the iron core, thereby ensuring the accuracy of the displacement sensor's detection results.
[0005] According to a first aspect of this application, an inductive displacement sensor is provided, comprising a sensitive element and a processing element. The sensitive element includes an iron core, an inductor coil, and a support. The iron core has a receiving groove and an opening. The depth direction of the receiving groove extends along the axial direction of the iron core. The opening is arranged on the side of the iron core and communicates with the receiving groove. The iron core is fixedly connected to the support. The inductor coil has leads at both ends.
[0006] The inductor coil is mounted in the housing cavity by adhesive bonding. The lead wire of the inductor coil is led out from the opening and electrically connected to the processing element. The processing element is used to receive and process the induction signal output by the sensitive element.
[0007] In a specific embodiment of this application, the iron core includes an integrally formed base plate, an outer circumference, and an inner circumference; the base plate is fixedly connected to a bracket; both the outer circumference and the inner circumference are disposed on the base plate; the outer circumference and the inner circumference are arranged coaxially, and the gap between the outer circumference and the inner circumference is a receiving groove; the outer circumference is provided with an opening.
[0008] In one particular embodiment of this application, the core also has a through hole; the through hole extends axially along the core and penetrates the inner circle and the base plate.
[0009] In one specific embodiment of this application, there are two openings, which are symmetrically arranged on both sides of the outer circumference.
[0010] In one specific embodiment of this application, the bracket includes an integrally formed base and a column; the base is disposed on the upper end face of the column; the upper end face of the base and the lower end face of the iron core are fixedly connected by adhesive bonding.
[0011] In a specific embodiment of this application, the base is frustum-shaped, with the upper end face of the base being narrow and the lower end face being wide; there is a gap between the base and the iron core.
[0012] In addition, this application also provides a method for manufacturing the above-mentioned inductive displacement sensor, comprising the following steps:
[0013] Step 1: Wind the inductor coil;
[0014] Step 2: Place the inductor coil into the receiving slot and lead the inductor coil out from the opening. Then use epoxy resin to bond the inductor coil to the iron core to obtain the sensor body.
[0015] Step 3: Check whether the electrical parameters of the sensor body are qualified. If qualified, proceed to step 4; if not qualified, disassemble the sensor body and return to step 1.
[0016] Step 4: Attach the sensor body to the bracket to obtain the displacement sensor.
[0017] In a specific embodiment of this application, during the bonding in step 2, the upper end face of the inductor coil does not extend beyond the upper end face of the receiving groove.
[0018] In a specific embodiment of this application, the electrical parameters of the sensor are detected using the bridge method in step 3.
[0019] In a specific embodiment of this application, during the bonding process in step 4, the lower end face of the sensor body and the upper end face of the bracket are parallel.
[0020] One of the above-mentioned technical solutions in this application has at least one of the following advantages or beneficial effects:
[0021] The sensing element of the inductive displacement sensor of this application adopts a modular design. Specifically, the inductor coil is wound first, and then the qualified inductor coil is placed in the iron core. Compared with the traditional structure, this avoids the defects such as inconsistent winding arrangement and inconsistent parameters caused by directly winding radially in the iron core. It can ensure the consistency of parameters such as the number of turns and arrangement of the inductor coil, and is particularly suitable for the mass production of inductor coils, which can effectively improve production capacity and reduce costs.
[0022] Meanwhile, the inductor coil is installed in the receiving groove by adhesive bonding. This installation method is not only simple in structure, but also ensures the stability of the inductor coil in the receiving groove, effectively preventing it from loosening or shifting during operation, thereby ensuring the accuracy and reliability of the displacement sensor measurement.
[0023] Furthermore, the fabrication method of the inductive displacement sensor of this application can ensure that the modularly designed sensitive elements fit together tightly, thereby ensuring the accuracy of the displacement sensor's detection results. Attached Figure Description
[0024] The present application will be further described below with reference to the accompanying drawings and embodiments;
[0025] Figure 1 This is a three-dimensional structural schematic diagram of the sensitive element in Embodiment 1 of this application;
[0026] Figure 2 This is an embodiment 1 of the present application. Figure 1 The front view;
[0027] Figure 3 This is a three-dimensional structural diagram of the iron core and inductor coil of Embodiment 1 of this application;
[0028] Figure 4 This is an embodiment 1 of the present application. Figure 3 Top view;
[0029] Figure 5 This is a three-dimensional structural diagram of the bracket according to Embodiment 1 of this application;
[0030] Figure 6 This is a simplified connection diagram of the inductive displacement sensor according to Embodiment 1 of this application;
[0031] Figure 7 This is a simplified flowchart of the fabrication process of the inductive displacement sensor of Embodiment 1 of this application.
[0032] The figure labels for each figure are as follows:
[0033] Sensitive element 1; iron core 11; base plate 111; outer circle 112; inner circle 113; inductor coil 12; bracket 13; base 131; column 132; receiving groove 101; opening 102; through hole 103; gap 104. Detailed Implementation
[0034] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.
[0035] The following discloses many different implementation methods or examples for different schemes to implement this application.
[0036] Reference Figures 1 to 7 As shown, an inductive displacement sensor includes a sensing element 1 and a processing element. The sensing element 1 includes an iron core 11, an inductor coil 12, and a support 13. The iron core 11 has a receiving groove 101 and an opening 102. The depth direction of the receiving groove 101 extends along the axial direction of the iron core 11. The opening 102 is arranged on the side of the iron core 11 and communicates with the receiving groove 101. The iron core 11 is fixedly connected to the support 13. The inductor coil 12 has leads at both ends.
[0037] The inductor coil 12 is installed in the receiving cavity by adhesive bonding. The lead wire of the inductor coil 12 is led out from the opening 102 and electrically connected to the processing element. The processing element is used to receive and process the sensing signal output by the sensing element 1.
[0038] The sensing element of the inductive displacement sensor in this embodiment adopts a modular design. Specifically, the inductor coil 12 is wound first, and then the qualified inductor coil 12 is placed in the iron core 11. Compared with the traditional structure, this avoids the defects such as inconsistent winding arrangement and inconsistent parameters caused by directly winding radially on the iron core 11. It can ensure the consistency of parameters such as the number of turns and arrangement of the inductor coil 12, and is particularly suitable for the mass production of the inductor coil 12, which can effectively improve production capacity and reduce costs.
[0039] Specifically, the iron core 11 includes an integrally formed base plate 111, an outer circular body 112, and an inner circular body 113; the base plate 111 is fixedly connected to the bracket 13; the outer circular body 112 and the inner circular body 113 are both disposed on the base plate 111; the outer circular body 112 and the inner circular body 113 are arranged coaxially, and the gap between the outer circular body 112 and the inner circular body 113 is a receiving groove 101; the outer circular body 112 is provided with an opening 102. In this design, the upper end face of the iron core 11 is open, and the receiving groove 101 extends from the upper end face to the lower end face of the iron core 11, forming an annular receiving groove 101. Since the inductor coil 12 is also annular, when the inductor coil 12 is placed into the receiving groove 101, the inner circular body 113 can limit the inner wall surface of the inductor coil 12 and play a limiting role. Then, the opening 102 extends from one side of the outer circumference 112 toward the center of the iron core 11, and the lead of the inductor coil 12 extends out from the opening 102 and is electrically connected to the processing element.
[0040] Furthermore, in this embodiment, in order to construct a stable magnetic field, the iron core 11 is made into a symmetrical structure with two openings 102. The two openings 102 are symmetrically arranged on both sides of the outer circle 112. In this embodiment, the leads at both ends of the inductor coil 12 are led out from the opening 102 on one side. Of course, in other embodiments, it is also feasible for the leads at both ends of the inductor coil 12 to be led out from the openings 102 on both sides respectively. At the same time, the iron core 11 also has a through hole 103; the through hole 103 extends along the axial direction of the iron core 11 and penetrates the inner circle 113 and the base plate 111.
[0041] In this embodiment, the bracket 13 includes an integrally formed base 131 and a column 132; the base 131 is disposed on the upper end face of the column 132; the upper end face of the base 131 and the lower end face of the iron core 11 are fixedly connected by adhesive. Specifically, the base 131 and the iron core 11 are bonded together with glue; more specifically, the base 131 is frustum-shaped, and the upper end face of the base 131 is narrow, and the lower end face of the base 131 is wide; there is a gap 104 between the base 131 and the iron core 11, and epoxy resin is applied to the gap 104 when the iron core 11 is bonded to the bracket 13, thereby making the bond between the iron core 11 and the bracket 13 more secure.
[0042] Under the above design, the displacement sensor of this embodiment can be applied to various scenarios, such as measuring the displacement of the rotating component of a split-type magnetic levitation molecular pump. The method of use is as follows: fix the bracket 13 on one side of the rotating component and make the axis of the rotating component coincide with the axis of the inductor coil 12, so that the open surface of the iron core 11 faces the end face of the rotating component. When the rotating component is working and displacement occurs in the axial direction, the displacement sensor can detect the change in axial displacement of the rotating component in real time and output it to the processing element through the lead wire. The processing element has a test circuit. The test circuit obtains the offset and feeds it back to the control system of the split-type magnetic levitation molecular pump, so as to adjust the axial position of the rotating component in a timely manner.
[0043] Furthermore, the manufacturing method of the aforementioned inductive displacement sensor includes the following steps:
[0044] Wind the inductor coil 12 and place it into the receiving groove 101. Ensure that the upper end of the inductor coil 12 does not exceed the upper end of the receiving groove 101, and that the leads of the inductor coil 12 are led out from the opening 102. Then, use epoxy resin to bond the inductor coil 12 to the iron core 11. Use heat shrink tubing to cover the leads at both ends of the inductor coil 12 to prevent short circuits, thus obtaining the sensor body. Note that the lower end of the sensor body is parallel to the upper end of the bracket 13. After the bonding is firm, use the bridge method to check whether the electrical parameters (voltage, resistance) of the sensor body are qualified. If qualified, bond the sensor body to the bracket 13 to obtain the displacement sensor. If not qualified, disassemble the sensor body and repeat the above steps.
[0045] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.
Claims
1. An inductive displacement sensor, comprising a sensing element and a processing element, characterized in that, The sensitive element includes an iron core, an inductor coil, and a support. The iron core has a receiving groove and an opening. The depth direction of the receiving groove extends along the axial direction of the iron core. The opening is arranged on the side of the iron core and communicates with the receiving groove. The iron core is fixedly connected to the support. The inductor coil has leads at both ends. The inductor coil is mounted in the receiving cavity by adhesive bonding, and the lead of the inductor coil is led out from the opening. The lead is electrically connected to the processing element, which is used to receive and process the sensing signal output by the sensing element.
2. The inductive displacement sensor according to claim 1, characterized in that, The iron core includes an integrally formed base plate, an outer circumference, and an inner circumference; the base plate is fixedly connected to the bracket; the outer circumference and the inner circumference are both disposed on the base plate; the outer circumference and the inner circumference are arranged coaxially, and the gap between the outer circumference and the inner circumference is the receiving groove; the outer circumference is provided with the opening.
3. The inductive displacement sensor according to claim 2, characterized in that, The iron core also has a through hole; the through hole extends along the axial direction of the iron core and penetrates the inner circle and the base plate.
4. The inductive displacement sensor according to claim 2, characterized in that, There are two openings, which are symmetrically arranged on both sides of the outer circumference.
5. The inductive displacement sensor according to claim 1, characterized in that, The bracket includes an integrally formed base and a column; the base is disposed on the upper end face of the column; the upper end face of the base and the lower end face of the iron core are fixedly connected by adhesive bonding.
6. The inductive displacement sensor according to claim 5, characterized in that, The base is frustum-shaped, with a narrow upper end and a wide lower end; there is a gap between the base and the iron core.
7. A method for manufacturing an inductive displacement sensor as described in any one of claims 1 to 6, characterized in that, Includes the following steps: Step 1: Wind the inductor coil; Step 2: Place the inductor coil into the receiving groove and lead the inductor coil out from the opening. Then, use epoxy resin to bond the inductor coil to the iron core to obtain the sensor body. Step 3: Check whether the electrical parameters of the sensor body are qualified. If qualified, proceed to step 4; if not qualified, disassemble the sensor body and return to step 1. Step 4: Attach the sensor body to the bracket to obtain the displacement sensor.
8. The method for manufacturing an inductive displacement sensor according to claim 7, characterized in that, In the bonding process of step 2, the upper end face of the inductor coil does not extend beyond the upper end face of the receiving groove.
9. The method for manufacturing an inductive displacement sensor according to claim 7, characterized in that, In step 3, the electrical parameters of the sensor are detected using the bridge method.
10. The method for manufacturing an inductive displacement sensor according to claim 7, characterized in that, In step 4, the lower end face of the sensor body is parallel to the upper end face of the bracket.