A circumferential fixed-movement combined capacitive sensor and coding positioning method

Abstract

The present invention provides a circumferential fixed-moving combined capacitive sensor and coding positioning method, belonging to the field of sensor technology, comprising a first cylinder; a plurality of fixed pole plates, fixedly arranged in the wall of the first cylinder, and the plurality of fixed pole plates are equidistantly distributed in the circumferential direction; a second cylinder, sleeved on the outer periphery of the first cylinder; a rotating pole plate, fixedly arranged in the wall of the second cylinder; the rotating pole plate is made to overlap with a certain fixed pole plate, the rotating pole plate is rotated, and the capacitance value between the rotating pole plate and the fixed pole plate is collected. When the rotating pole plate overlaps with the next fixed pole plate, the capacitance value between the rotating pole plate and the overlapping fixed pole plate begins to be collected, and the capacitance value is related to the circumferential distance between the two pole plates. Each time the rotating pole plate overlaps with the next fixed pole plate, a periodic capacitance signal is generated, and the pole plate rotates one circle to generate a coding signal with the same number of periods as the number of fixed pole plates. The device can describe the material distribution inside a tubular object with a signal.

Description

Technical Field

[0001] The present invention belongs to the field of sensor technology, and specifically relates to a capacitive sensor with encoding function. Background Art

[0002] Capacitive sensing technology is a technology based on capacitive coupling, which can be used to detect any conductive dielectric that is different from air. Capacitive sensing is widely used to measure physical quantities such as pressure, position, displacement, force, humidity, liquid level and acceleration. Capacitive sensing has high sensitivity, good stability, fast response and wide application. It is currently widely used in the field of non-destructive testing.

[0003] In the prior art, capacitive sensing technology used for positioning detection of materials inside an object utilizes two plates with a constant circumferential spacing to be attached to the surface of the object, the two plates are simultaneously moved on the surface of the object or rotated around the surface of the object, the capacitive signal is collected, and the positioning information of the material inside the object is obtained by analyzing the capacitive signal.

[0004] However, there is a problem in the prior art that the output signal is not easy to convert into a digital signal, which is not conducive to signal processing. Summary of the invention

[0005] In order to overcome the above-mentioned deficiencies in the prior art, the present invention provides a circumferential fixed-moving combined capacitive sensor and a coding positioning method.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A capacitive sensor with encoding function, comprising:

[0008] First cylinder;

[0009] A plurality of fixed electrode plates are fixedly arranged in the wall of the first cylinder, and the plurality of fixed electrode plates are equally spaced in the circumferential direction;

[0010] A second cylinder, sleeved on the outer periphery of the first cylinder;

[0011] A rotating pole plate is fixedly arranged in the wall of the second cylinder;

[0012] Make the rotating pole plate overlap with one of the fixed pole plates, rotate the rotating pole plate, and collect the capacitance value between the rotating pole plate and the fixed pole plate; when the rotating pole plate overlaps with the next fixed pole plate, start collecting the capacitance value between the rotating pole plate and the fixed pole plate, and so on; the capacitance value is related to the circumferential distance between the two pole plates, and each time the rotating pole plate overlaps with the next adjacent fixed pole plate, a period of capacitance signal is generated, and the rotating pole plate rotates one circle to generate a coded signal with the same number of periods as the fixed pole plates.

[0013] Furthermore, a shift block is fixedly connected to the outer wall of the second cylinder.

[0014] Furthermore, the length of the second cylinder is shorter than that of the first cylinder.

[0015] Furthermore, a slide groove is provided on the outer wall of the first cylinder, and a slider is provided on the inner wall of the second cylinder, and the slider is located in the slide groove.

[0016] A coding positioning method, characterized by comprising:

[0017] Putting the first cylinder on the object to be detected;

[0018] Connecting the rotating pole plate and the fixed pole plate to a detection circuit;

[0019] The second cylinder is controlled to rotate around the first cylinder for one circle, and the capacitance values ​​between the adjacent fixed pole plates and the rotating pole plates along the rotating direction of the rotating pole plates are collected in sequence to obtain a coded signal describing the positioning information of the internal material of the object to be detected.

[0020] The capacitive sensor with encoding function provided by the present invention has the following beneficial effects:

[0021] During the rotation of the rotating pole plate, each time the rotating pole plate moves from the position where it overlaps with one fixed pole plate to the position where it overlaps with the next fixed pole plate, a periodic capacitance signal is generated. The size of the capacitance signal is affected by the distance between the rotating pole plate and the fixed pole plate, as well as the medium distribution of the measured object.

[0022] When there is no medium in the object or the medium is uniform, the rotating pole plate rotates around the surface of the object once, and a periodic signal with the same number of periods as the fixed pole plate can be obtained. When there is an inhomogeneous medium in the object, the periodic signal will be affected by the distribution of the medium and produce certain changes. Compared with the signal generated by rotating two pole plates with a constant spacing in the prior art, the coded signal generated by the present invention is easier to discretize, easier to convert into a digital signal, and more convenient for subsequent signal processing. It solves the problem in the prior art that the output signal is not easy to convert into a digital signal, which is not conducive to signal processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiment of the present invention and its design scheme, the following briefly introduces the drawings required for this embodiment. The drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1This is a schematic structural diagram of a circumferential fixed and movable combined capacitive sensor according to Embodiment 1 of the present invention;

[0025] Figure 2 This is a schematic diagram of the combined structure of the first cylinder and the second cylinder of Example 2 of the present invention;

[0026] Figure 3 The capacitance signal generated by using the existing bipolar plate capacitance sensor to detect an object in the third embodiment of the present invention is

[0027] Figure 4 This is a capacitance signal generated by detecting an object using the present invention according to embodiment 3 of the present invention. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the technical solution of the present invention and implement it, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the scope of protection of the present invention.

[0029] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the technical solutions of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0030] In addition, the terms "first", "second", etc. are used for descriptive purposes only and are not to be understood as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless otherwise clearly specified or limited, the terms "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. In the description of the present invention, unless otherwise specified, "plurality" means two or more, which will not be described in detail here.

[0031] Embodiment 1:

[0032] The present invention provides a capacitive sensor with encoding function, specifically Figure 1 As shown, including:

[0033] A first cylinder 5; a plurality of fixed pole plates 3, fixedly arranged in the wall of the first cylinder 5, and the plurality of fixed pole plates 3 are equidistantly distributed in the circumferential direction; a second cylinder 4, sleeved on the outer periphery of the first cylinder 5; a rotating pole plate 2, fixedly arranged in the wall of the second cylinder 4; the sensor is based on capacitance tomography technology, so that the rotating pole plate 2 coincides with a certain fixed pole plate 3, and the rotating pole plate 2 is rotated to collect capacitance values ​​between adjacent fixed pole plates 3 and the rotating pole plate 2 along the rotation direction of the rotating pole plate 2 in turn, and the capacitance value is related to the circumferential distance between the two pole plates, and each time the rotating pole plate 2 coincides with the next adjacent fixed pole plate 3, an identical capacitance signal is generated, and the rotating pole plate 2 generates a coded signal with the same number of cycles as the number of fixed pole plates 3 when the rotating pole plate 2 rotates one circle.

[0034] In this embodiment, the fixed electrode plate 3 and the rotating electrode plate 2 are co-arc surface capacitors, the fixed electrode plate 3 and the rotating electrode plate 2 are used to generate capacitance signals, and the first cylinder 5 is used to be sleeved on the object to be detected. When in use, the rotating electrode plate 2 is used as an excitation electrode plate, and the rotating electrode plate 2 is rotated. When the rotating electrode plate 2 coincides with a fixed electrode plate, the next fixed electrode plate along its rotation direction is used as a receiving electrode plate, and the capacitance signal between the two is continuously collected until the rotating electrode plate 2 coincides with the next fixed electrode plate, and so on. When the rotating substrate 2 is rotated one circle, a capacitance encoding signal with the same number of cycles as the number of fixed electrodes can be obtained.

[0035] By applying this embodiment, when there is no medium or a uniform medium in the object, the rotating pole plate 3 is rotated around the surface of the object to be detected for one circle, and a capacitance coding signal with the same number of cycles as the number of fixed pole plates can be obtained. When there is an inhomogeneous medium in the object, the periodic capacitance signal will be affected by the distribution of the material in the object to be detected and produce certain fluctuations. By collecting the signal, the information of the material distribution in the object can be obtained. Compared with the prior art, the present device can increase the number of cycles of the coding signal by setting a plurality of fixed pole plates. The coding signal can produce more changes and obtain more information relative to the signal generated by the prior art. And the signal is more convenient for discretization, so that the collected analog signal is easier to convert into a digital signal, which facilitates the processing of the signal.

[0036] Embodiment 2:

[0037] like Figure 2 , as shown, based on Example 1:

[0038] The outer wall of the second cylinder 4 is fixedly connected with a shifting block 1, and the length of the second cylinder 4 is shorter than that of the first cylinder 5. The outer wall of the first cylinder 5 is provided with a slide groove 7, and the inner wall of the second cylinder 4 is provided with a slider 6, which is located in the slide groove 7.

[0039] By applying this embodiment, the setting of the shifting block 1 can conveniently shift the second cylinder 4 to rotate around the first cylinder 5. Since the length of the second cylinder 4 is shorter than that of the first cylinder 5, the side wall of the first cylinder 5 can be held with one hand, and the second cylinder 4 can be shifted to rotate with the other hand, making the operation more convenient. The slide groove 7 and the slider 6 are used to limit the axial position of the first cylinder 5, which can prevent the first cylinder 5 from sliding along the axial direction of the second cylinder 4 and causing measurement errors.

[0040] Embodiment 3:

[0041] The present invention provides a coding positioning method, comprising:

[0042] The first cylinder 5 is put on the object to be detected; the rotating pole plate 2 and the fixed pole plate 3 are connected to the detection circuit; the second cylinder 4 is controlled to rotate around the first cylinder 5 for one circle, and the capacitance values ​​between the adjacent fixed pole plates 3 and the rotating pole plate 2 along the rotation direction of the rotating pole plate 2 are collected in turn to obtain a coded signal describing the positioning information of the internal material of the object to be detected.

[0043] By applying this embodiment, the material distribution and positioning information inside the object can be converted into a coded signal, and the internal information can be obtained by analyzing the coded signal.

[0044] like Figure 3 To detect the capacitance signal generated by an object using an existing bipolar plate capacitance sensor, such as Figure 4 By using the present invention to detect the capacitance signal generated by the object, it can be seen that the signal generated by the present invention is more convenient to be converted into a digital signal, which facilitates signal processing.

[0045] The embodiments described above are only preferred specific implementation modes of the present invention, and the protection scope of the present invention is not limited thereto. Any simple changes or equivalent replacements of the technical solutions that can be obviously obtained by any technician familiar with the field within the technical scope disclosed in the present invention belong to the protection scope of the present invention.

Claims

1. A method for using a circumferential fixed-moving combined capacitive sensor, characterized in that: include: A first cylinder (5); A plurality of fixed electrode plates (3) are fixedly arranged in the wall of the first cylinder (5), and the plurality of fixed electrode plates (3) are equidistantly distributed in the circumferential direction; The second cylinder (4) is sleeved on the outer periphery of the first cylinder (5); the outer wall of the first cylinder (5) is provided with a slide groove (7), the inner wall of the second cylinder (4) is provided with a slider (6), and the slider (6) is located in the slide groove (7); A rotating pole plate (2) fixedly arranged in the wall of the second cylinder (4); The first cylinder (5) is used to be sleeved on the object to be detected. When in use, the rotating pole plate (2) is used as an excitation pole plate, and the rotating pole plate (2) is rotated so that the rotating pole plate (2) overlaps with a certain fixed pole plate (3). The rotating pole plate (2) is rotated to collect the capacitance value between the rotating pole plate (2) and the fixed pole plate (3). When the rotating pole plate (2) overlaps with the next fixed pole plate (3), the capacitance value between the rotating pole plate (2) and the fixed pole plate (3) begins to be collected, and so on. The capacitance value is related to the circumferential distance between the two pole plates. Each time the rotating pole plate (2) overlaps with the next adjacent fixed pole plate (3), a period of capacitance signal is generated. The rotating pole plate (2) rotates one circle to generate a capacitance encoding signal with the same number of periods as the fixed pole plate (3). The capacitance encoding signal represents the location information of the substance in the object to be detected.

2. The method for using a circumferential fixed-moving combined capacitive sensor according to claim 1, characterized in that: A shifting block (1) is fixedly connected to the outer wall of the second cylinder (4).

3. The method for using a circumferential fixed-moving combined capacitive sensor according to claim 1, characterized in that: The length of the second cylinder (4) is shorter than the length of the first cylinder (5).

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