Integrated conductive base applied to angle sensor

Abstract

The invention belongs to the field of sensor design, and particularly relates to an integrated conductive base applied to an angle sensor. A traditional base assembly is large in machining difficulty and low in qualified rate of finished products, and welding spots are prone to breakage. The flexible printed circuit board comprises a conversion board, an FPC flexible board, an angle board and conducting strips, the conversion board and the angle board are hard boards, the conducting strips are distributed on the outer end face of the angle board at intervals, etching copper wires corresponding to the conducting strips are arranged on the inner end face of the angle board, the FPC flexible board is in lap joint with the copper wires at a wire outlet, and the FPC flexible board is in lap joint with the conversion board at the outer end. The conversion board, the FPC soft board, the angle board and the conducting strip are formed into a whole in a hot press mode under the vacuum condition, a conducting hole between the conducting strip and the copper wire is drilled in the angle board, and the hole wall is plated with copper to be communicated. Complicated bonding and machining procedures are not needed, the integrally pressed plane is high in flatness, the conducting strips are firmly combined, the falling risk does not exist, and measurement of multiple paths of angle signals can be achieved at the same time.

Description

Technical Field

[0001] The invention belongs to the field of sensor design, and in particular relates to an integrated conductive base applied to an angle sensor. Background Art

[0002] The conductive base of the angle sensor is an important angle measurement component. Figure 1-2 The traditional structure is to first bond the conductive sheet a to the non-metallic base b with an adhesive such as epoxy glue, then use a lathe to turn the plane where the conductive sheet a and the non-metallic base b are located to obtain a higher flatness, and finally directly weld the end of the wire on the conductive sheet a for signal output, and the wire is arranged in the internal wire groove c.

[0003] The above structure has the following problems: The bonding and soldering of wires are all done manually, which requires high skills of operators. The traditional base assembly is a combination of two materials, which is difficult to machine and has a low qualified rate of finished products. In addition, there is a risk that the conductive sheet is not firmly bonded and is easy to fall off. When the wire is welded to the conductive sheet, the solder joint is prone to breakage under mechanical conditions such as force or vibration of the wire, which then causes failure. Summary of the invention

[0004] The purpose of the present invention is to provide a new structural design of an integrated conductive base, which is applied to angle sensors requiring multi-channel angle signal measurement and high reliability.

[0005] The present invention provides an integrated conductive base applied to an angle sensor, the integrated conductive base comprises a conversion plate, an FPC soft board, an angle plate and a conductive sheet, wherein the conversion plate and the angle plate are hard boards, a plurality of conductive sheets are spaced apart on the outer end surface of the angle plate, an etched copper wire corresponding to each conductive sheet is provided on the inner end surface of the angle plate, the FPC soft board is overlapped with the copper wire at the wire outlet, the FPC soft board is overlapped with the conversion plate at the outer end, the conversion plate, the FPC soft board, the angle plate and the conductive sheet are hot-pressed into one under vacuum conditions, a conducting hole between the conductive sheet and the copper wire is drilled on the angle plate, and the hole wall is copper-plated for connection.

[0006] Advantageously, a plurality of pads for electrical connection are designed on the conversion board.

[0007] Advantageously, the angle range that can be measured by the conductive sheet on the angle plate can be flexibly designed according to the indicators of the actual angle sensor.

[0008] Advantageously, the surface of the conductive sheet is subjected to wear-resistant and anti-oxidation treatment.

[0009] Advantageously, a mounting groove is designed on the angle plate for mounting and fixing the conductive base.

[0010] Advantageously, to process the etched copper wire, the film pattern needs to be transferred to the dry film on the board surface inside the angle plate through the principle of optical imaging; then the non-conductive copper layer is partially corroded away through development and etching.

[0011] Advantageously, the angle plate and the conversion plate are made of FR-4 material with a high TG value, a multi-layer laminated structure, and a temperature resistance of the material of not less than 170°C.

[0012] Advantageously, the FPC is made of polyimide.

[0013] Advantageously, epoxy glue is applied to the roots of the connections between the FPC soft board and the conversion board and the angle board for reinforcement.

[0014] Advantageously, the conductive sheet is designed to be in the shape of a sector having the same center as the angle plate.

[0015] Beneficial effects: The structure of the present invention is compact and can be applied to angle sensors with smaller spaces. Compared with the traditional structure, it does not require complicated bonding and machining processes, the flatness of the integrated pressed surface is high, the conductive sheet is firmly combined, there is no risk of falling off, and it can simultaneously realize the measurement of multiple angle signals.

[0016] Inner copper wires are used instead of traditional wires for electrical connection, avoiding the risk of wire solder joint failure and greatly improving reliability.

[0017] The features, functions, and advantages that have been discussed can be achieved independently in various examples or may be combined in yet other examples. Further details of the examples can be seen with reference to the following description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Examples, as well as preferred modes of use, other objects and description thereof, will be best understood by reference to the following detailed description of examples of the invention when read in conjunction with the accompanying drawings, in which:

[0019] Figure 1 It is a schematic diagram of the external structure of a traditional conductive base;

[0020] Figure 2 It is a schematic diagram of the internal structure of a traditional conductive base;

[0021] Figure 3 It is a structural schematic diagram of the integrated conductive base of the present invention.

[0022] a-conductive sheet, b-non-metallic base, c-wire slot, 1-conversion board, 2-FPC soft board, 3-angle board, 4-conductive sheet DETAILED DESCRIPTION

[0023] The disclosed examples will be more fully described with reference to the accompanying drawings, in which some (but not all) of the disclosed examples are shown. In fact, many different examples may be described and these examples should not be construed as limited to the examples set forth herein. Instead, these examples are described so that this disclosure will be thorough and complete and will fully convey the scope of the disclosure to those skilled in the art.

[0024] Now refer to the attached Figure 3 The structure of the integrated conductive base shown in the figure, the conductive sheet 4 on the angle plate 3 is used for angle signal measurement, and multiple independent conductive sheets 4 are designed on the angle plate 3, which can simultaneously perform multiple independent angle signal measurements. The conductive sheet 4 is connected to the conversion board 1 through the inner copper wire through the FPC soft board 2, and the conversion board 1 is designed with a pad for outputting the signal. The conversion board 1, the FPC soft board 2, the angle plate 3 and the conductive sheet 4 on the angle plate 3 are made by integral pressing.

[0025] The angle plate 3 and the conversion plate 1 are made of FR-4 material with a high TG value and a multi-layer laminated structure. The material has a temperature resistance of not less than 170°C and can be used in high temperature environments.

[0026] The FPC soft board 2 is made of polyimide material, δ0.12mm (the thinnest FPC soft board process can reach 0.07mm at present), and the roots of the connection between the FPC soft board 2 and the conversion board 1 and the angle board 3 are coated with epoxy glue for reinforcement. The minimum bending radius of the FPC soft board 2 is 3mm, which can be used in 90° and 180° angle bending scenarios.

[0027] The conductive sheet 4 is designed to be a sector with the same center as the angle plate 3. Multiple conductive sheets 4 can be designed on the angle plate 3. Each conductive sheet 4 can be designed to have a different angle. The conductive sheets 4 are independent of each other, and the inner copper wires are independently arranged. The measurement of multiple angle signals can be realized at the same time or used for redundant design. The conductive sheet 4, the angle plate 3, the conversion board 1 and the FPC soft board 2 are pressed together, and the surface of the conductive sheet 4 is plated with hard gold to improve its wear resistance and anti-oxidation ability.

[0028] The process of integrated pressing is:

[0029] ① Cutting of hard and soft boards: Cutting of hard and soft board substrates, copper-clad boards, etc. according to the designed dimensions;

[0030] ② Drilling via holes: drilling circuit connection via holes, black holes and copper-plated holes, etc.;

[0031] ③ Exposure: Transfer the film pattern to the dry film on the inner side of the angle plate 3 through the principle of optical imaging;

[0032] ④Development and etching: corrode part of the non-conductive copper layer;

[0033] ⑤ Vacuum pressing of soft and hard boards: hot pressing the soft and hard boards under vacuum conditions;

[0034] ⑥ Secondary drilling and copper plating: drilling via holes and copper plating the hole walls;

[0035] ⑦Electroplating: electroplating thick copper layer and hard gold on conductive sheet.

[0036] The pads on the conversion board 1 are designed according to the specific lead-out form. In the common wire lead-out form, the pad hole diameter is designed to be 0.2-0.3 mm larger than the corresponding wire core diameter, and the wire hole diameter is designed to be 0.1 mm larger than the wire outer diameter.

[0037] Descriptions of different advantageous arrangements have been presented for purposes of illustration and description, but the description is not intended to be exclusive or limited to examples of the disclosed form. Many modifications and variations will be apparent to those of ordinary skill in the art. Additionally, different advantageous examples may be described as having different advantages over other advantageous examples. The selected example or examples are selected and described in order to best illustrate the principles of the examples, practical applications, and to enable those of ordinary skill in the art to understand the disclosure as having various examples with various modifications suitable for the particular use contemplated.

Claims

1. An integrated conductive base for an angle sensor, characterized in that: The integrated conductive base comprises a conversion plate (1), an FPC soft plate (2), an angle plate (3) and a conductive sheet (4), wherein the conversion plate (1) and the angle plate (3) are hard plates, a plurality of conductive sheets (4) are spaced apart on the outer end surface of the angle plate (3), an etched copper wire corresponding to each conductive sheet (4) is provided on the inner end surface of the angle plate (3), the FPC soft plate (2) is overlapped with the copper wire at the wire outlet, and the FPC soft plate (2) is overlapped with the conversion plate (1) at the outer end, the conversion plate (1), the FPC soft plate (2), the angle plate (3) and the conductive sheet (4) are hot-pressed into one piece under vacuum conditions, and a conducting hole between the conductive sheet (4) and the copper wire is drilled on the angle plate (3) and connected by copper plating on the hole wall.

2. The integrated conductive base for angle sensor according to claim 1, characterized in that: A number of pads for electrical connection are designed on the conversion board (1).

3. The integrated conductive base for angle sensor according to claim 1, characterized in that: The angle range that can be measured by the conductive sheet (4) on the angle plate (3) is flexibly designed according to the indicators of the actual angle sensor.

4. The integrated conductive base for angle sensor according to claim 1, characterized in that: The surface of the conductive sheet (4) is subjected to wear-resistant and anti-oxidation treatment.

5. The integrated conductive base for angle sensor according to claim 1, characterized in that: A mounting groove is designed on the angle plate (3) for mounting and fixing the conductive base.

6. The integrated conductive base for angle sensor according to claim 1, characterized in that: To process the etched copper wire, the film pattern needs to be transferred to the dry film on the board surface inside the angle plate (3) through the principle of optical imaging; then the non-conductive copper layer is partially etched away through development and etching.

7. The integrated conductive base for angle sensor according to claim 1, characterized in that: The angle plate (3) and the conversion plate (1) are made of FR-4 material with a high TG value and are a multi-layer pressed structure. The material has a temperature resistance of not less than 170°C.

8. The integrated conductive base for angle sensor according to claim 1, characterized in that: The material of the FPC soft board (2) is polyimide.

9. The integrated conductive base for angle sensor according to claim 1, characterized in that: Epoxy glue is applied to the roots of the connections between the FPC soft board (2), the conversion board (1) and the angle board (3) for reinforcement.

10. The integrated conductive base for angle sensor according to claim 1, characterized in that: The conductive sheet (4) is designed to be in the shape of a sector having the same center as the angle plate (3).

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