Sensor capable of measuring rotation angle, direction and speed and measurement method thereof

Abstract

The invention belongs to the technical field of sensors, and provides a sensor capable of measuring the rotation angle, direction and speed and a measuring method thereof.The sensor comprises a magnetic module, a fixing module and an induction module, the magnetic module comprises two pieces of semi-annular magnetic steel, each piece of semi-annular magnetic steel is provided with a single pair of magnetic poles, and the two pieces of magnetic steel are arranged in a heteropole opposite mode; the magnetic field is provided for measurement of the sensor; the fixing module comprises two magnetizers of an annular structure and is used for directly connecting the magnetic steel with a tested workpiece. The sensing module comprises two sensing elements, and the two sensing elements are fixed to the positions with the same distance away from the rotating center of the measured workpiece. The sensor provided by the invention can measure the rotation angle, direction and speed of the measured workpiece at the same time, the overall structure is simple, and since continuous analog quantity signals are generated by the pair of magnetic steels and can be subdivided infinitely, the sensor can measure the angle position with very high precision and can distinguish the rotation direction at the same time.

Description

Technical Field

[0001] The present invention belongs to the technical field of sensors, and in particular relates to a sensor capable of measuring rotation angle, direction and speed and a measurement method thereof. Background Art

[0002] As a core component for detecting the rotation angle of an object or shaft, angle sensors have evolved from mechanical to intelligent, and from single-function to multi-physics integration. Currently, angle sensors are widely used to measure the rotation angle of automatic control equipment, such as industrial automation equipment and construction machinery.

[0003] Current magnetic encoders use a multi-pole approach. The higher the accuracy requirement, the more poles are needed, resulting in a larger overall structure and increased manufacturing costs. Summary of the Invention

[0004] The object of the present invention is to overcome the existing defects and provide a sensor capable of measuring rotation angle, direction and speed and a measurement method thereof.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A first object of the present invention is to provide a sensor capable of measuring rotation angle, direction, and speed, comprising:

[0007] The magnetic module includes two semi-circular magnets, each of which has a single pair of magnetic poles and is arranged with opposite poles, and is used to provide a magnetic field for the sensor's measurement;

[0008] The fixing module includes two ring-shaped magnetic conductors for directly connecting the magnetic steel to the workpiece to be measured;

[0009] The sensing module includes two sensing elements, which are fixed at positions with equal distances from the rotation center of the workpiece to be measured.

[0010] Furthermore, one end surface of the magnetic steel is semicircular, and the other end surface is in the shape of a sine curve or other convex function curve so that the response signal generated by the magnetic field of the magnetic steel to the sensor is in the shape of a sine curve or other convex function curve.

[0011] Furthermore, the magnetization direction of the magnetic steel adopts parallel magnetization along the surface of the magnetic steel.

[0012] Furthermore, there is a fixed angular distance between the two sensing elements and the rotation center of the workpiece being measured.

[0013] Furthermore, the relative directions of the two sensing elements and the rotation center of the measured workpiece are perpendicular to each other.

[0014] Another object of the present invention is to provide a measurement method for the sensor capable of measuring rotation angle, direction, and speed as described in the first object, the measurement method comprising:

[0015] A and B represent the function values of the response curves of the two sensor elements, and C represents the angle of rotation of the rotating element, then:

[0016] A=Hsin(C)

[0017] B=Hsin(C+ψ)

[0018] Where H is the amplitude of the response curve, which can be calibrated (by reading the maximum / minimum values beforehand); ψ is the angle between the two sensing elements relative to the center of rotation. The response values measured from the two sensing elements can be used to determine the angle C of rotation of the rotating element from the above two formulas:

[0019] C = arc (A / H);

[0020] By analyzing the size and positive and negative of the A and B signals, the rotation direction and speed can be determined.

[0021] Another object of the present invention is to provide another measurement method, comprising:

[0022] Measure and pre-store the response data of the sensor element when the magnet rotates at different angles;

[0023] During actual measurement, the response data measured by the sensor element is compared with the stored data to determine the size of the rotation angle.

[0024] In combination with the above technical solutions, the present invention has the following beneficial effects compared with the prior art:

[0025] The sensor provided by the present invention can simultaneously measure the rotation angle, direction and speed of the workpiece being measured. The overall structure is simple. Since a pair of magnetic steels generate a continuous analog signal that can be infinitely subdivided, it can measure the angular position with high precision and distinguish the rotation direction at the same time.

[0026] In summary, the sensor provided by the present invention has the advantages of high precision, simple structure, easy miniaturization and low manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0028] Figure 1Schematic diagram of the structure of a sensor capable of measuring rotation angle, direction, and speed provided by an embodiment of the present invention, wherein a is a schematic diagram of a semicircular inner surface of a magnetic steel, and b is a schematic diagram of a semicircular outer surface of a magnetic steel;

[0029] Figure 2 is a schematic diagram of a magnetic steel with a semicircular inner surface provided by an embodiment of the present invention;

[0030] Figure 3 Schematic diagram of the magnetization direction of the magnetic steel provided by an embodiment of the present invention;

[0031] Figure 4 Schematic diagram of a response curve of a sensor element provided by an embodiment of the present invention.

[0032] In the figure: 1. Sensing element; 2. Magnet; 3. Magnetic conductor. DETAILED DESCRIPTION

[0033] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0034] like Figure 1 FIG. 1 is an embodiment of a sensor and a method for measuring rotation angle, direction and speed provided by the present invention, including

[0035] The magnetic module includes two semicircular magnets, which are used to provide a magnetic field for the sensor's measurement. The N and S poles of the two magnets are installed in opposite directions.

[0036] The fixing module includes two ring-shaped magnetic conductors for directly connecting the magnetic steel to the workpiece to be measured;

[0037] The sensing module includes two sensing elements, which are fixed at positions with equal distances from the rotation center of the workpiece to be measured.

[0038] Preferably, in the embodiment of the present invention, one end surface of the magnet is semicircular, and the other end surface is shaped so that the response signal generated by the magnetic field of the magnet to the sensor is a sine curve or other convex function curve.

[0039] Specifically, one surface (inner or outer) of the magnet is semicircular, with its center coinciding with the axis of rotation. The other surface (outer or inner) is shaped in a manner such that the magnetic field generated by the magnet during rotation produces a response signal close to a sinusoidal curve.

[0040] Preferably, in the embodiment of the present invention, two sensing elements are installed at appropriate positions of the stationary component, the two sensing elements are equidistant from the rotation center, and their radii are perpendicular to each other or spaced at a fixed angle.

[0041] like Figure 3 As shown, the magnetization direction of the magnetic steel in the embodiment of the present invention adopts parallel magnetization along the surface of the magnetic steel.

[0042] like Figure 4 As shown, the two sensing elements are arranged perpendicular to each other in the relative directions of the rotation center of the workpiece being measured. At position A in the figure, the absolute value of the magnetic field strength of the magnet is the largest, and the absolute value of the response of the magnetic field to sensor element A is the largest, and the direction depends on the polarity of the magnet. At this time, the absolute value of the response of sensor element B is the smallest, close to zero. Assuming that the rotating element being measured rotates counterclockwise, then during the rotation process, the response of the magnetic field sensor element A gradually decreases, while the response of sensor element B gradually increases. When the angle of the rotating workpiece reaches 90 degrees, the absolute value of sensor element A becomes 0, the minimum; and the absolute value of sensor element B becomes the maximum. Obviously, when the rotating workpiece rotates one circle, the response curves of the two sensor elements are sinusoidal curves. Since the position difference between them is 90 0 , so there is a 90° gap between their response curves. 0 Phase difference.

[0043] A and B represent the function values of the response curves of sensor element A and sensor element B respectively, and C represents the angle of rotation of the rotating element, then:

[0044] A=Hsin(C)

[0045] B=Hsin(C+90 0 )

[0046] Where H is the amplitude of the response curve. For a given magnet, sensor element, and their relative position, it is a known value. Therefore, if the rotation angle C1 is known, the response value of the two sensor elements at the corresponding angle C1 can be calculated:

[0047] A1=Hsin(C1)

[0048] B1=Hsin(C1+90 0 )

[0049] Conversely, as long as the response values A1 and B1 are measured from the two sensor elements, the angle C1 of the rotating element can be uniquely determined from the above two formulas, where A1, B1, and C1 are all data with different phases from A, B, and C.

[0050] Since a pair of magnets generates a continuous analog signal that can theoretically be infinitely subdivided, it can measure the angular position with high precision and identify the direction of rotation.

[0051] In addition to using the above formula to determine the measured angle, you can also use the stored response data method to determine the measured angle. This method measures the sensor's response when the magnet is rotated through a series of different angles and stores the data in advance. The measured data is then compared with the stored data during actual measurement to determine the angle of rotation.

[0052] This sensor can determine the rotation direction and speed of the rotating shaft by analyzing the size and positive and negative of the A and B signals.

[0053] In the description of the present invention, unless otherwise specified, "plurality" means two or more; terms such as "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," and "tail" indicate positions or relationships based on those shown in the accompanying drawings. These terms are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limiting the present invention. Furthermore, terms such as "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0054] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A sensor capable of measuring rotation angle, direction and speed, characterized in that: The sensor comprises: The magnetic module includes two semi-circular magnets, each of which has a single pair of magnetic poles and is arranged with opposite poles, and is used to provide a magnetic field for the sensor's measurement; The fixing module includes two ring-shaped magnetic conductors for directly connecting the magnetic steel to the workpiece to be measured; The sensing module includes two sensing elements, which are fixed at positions with equal distances from the rotation center of the workpiece to be measured.

2. The sensor capable of measuring rotation angle, direction and speed according to claim 1, characterized in that: One end surface of the magnetic steel is semicircular, and the other end surface is shaped so that the response signal generated by the magnetic field of the magnetic steel to the sensor is in the shape of a sine curve or other convex function curve.

3. The sensor capable of measuring rotation angle, direction and speed according to claim 1, wherein: The magnetization direction of the magnetic steel is parallel to the surface of the magnetic steel.

4. The sensor capable of measuring rotation angle, direction and speed according to claim 1, wherein: There is a fixed angular distance between the two sensing elements and the relative directions of the rotation center of the workpiece to be measured.

5. The sensor capable of measuring rotation angle, direction and speed according to claim 4, characterized in that: The two sensing elements are perpendicular to each other in relative directions with respect to the rotation center of the workpiece being measured.

6. A measurement method for a sensor capable of measuring rotation angle, direction and speed according to any one of claims 1 to 5, characterized in that: The measuring method comprises: A and B represent the function values of the response curves of the two sensor elements, and C represents the angle of rotation of the rotating element, then: A=Hsin(C) B=Hsin(C+ψ) Where H is the amplitude of the response curve, ψ is the angle between the two sensing elements relative to the center of rotation, and the response values measured from the two sensing elements can be used to determine the angle C of the rotating element from the above two formulas: C = arc (A / H); By analyzing the size and positive and negative of the A and B signals, the rotation direction and speed are determined.

7. A measurement method for a sensor capable of measuring rotation angle, direction and speed according to any one of claims 1 to 5, characterized in that: The measuring method comprises: Measure and pre-store the response data of the sensor element when the magnet rotates at different angles; During actual measurement, the response data measured by the sensor element is compared with the stored data to determine the size of the rotation angle; By analyzing the size and positive and negative of the A and B signals, the rotation direction and speed are determined.

Images