TWI662255B - Magnetic encoder for measuring deflection of rotating shaft and device thereof - Google Patents

Abstract

A magnetic encoder for measuring the deviation of a rotating shaft includes a ring-shaped base body and a magnetic encoding unit. The annular substrate is made of a magnetically permeable material and includes two opposite first surfaces and a second surface. The magnetic encoding unit is disposed on one of the first surface and the second surface of the annular base, and includes a plurality of first magnetic poles and second magnetic poles that are staggered in a concentric circle with a central axis of the annular base. In addition, the present invention also provides a magnetic encoding device which is suitable for being mounted on a rotating shaft for measuring the deviation of the rotating shaft. The magnetic encoding device includes the aforementioned encoder and a sensor. The encoder is arranged around the rotation axis. The sensor is disposed at a distance from the magnetic encoder corresponding to the magnetic encoding unit.

Description

Magnetic encoder for measuring deflection of rotating shaft and device thereof

The invention relates to an encoder, in particular to a magnetic encoder and a device for measuring the deviation of a rotating shaft.

In the prior art, an encoder is usually used to measure the position of a rotating device. For example, the Republic of China Patent No. I241063 (hereinafter referred to as the former case) proposes a thin absolute position magnetic encoder, which mainly includes a plurality of axially magnetized shafts. The magnetic ring and the radially magnetized radial magnetic ring are alternately arranged in a flat disc shape, and the number of magnetic ring poles in the adjacent magnetic rings increases from the inside to the outside (that is, the number of magnetic poles in the outer ring will be more) Based on the number of magnetic poles in the inner ring) to form an absolute encoder.

In the previous case, the axial magnetic ring and the radial magnetic ring are staggered with each other to avoid mutual interference between the two magnetic rings and reduce the use of a neutral isolation ring for isolation. However, when the measurement is required, the magnetization direction will be the same. When the magnetic rings are arranged next to each other, it is still necessary to set a neutral isolation ring as a gap between the two magnetic rings, which will still increase the component volume. In addition, the main purpose of the staggered arrangement of the axial magnetic ring and the radial magnetic ring in the previous case is to achieve an absolute position, which is an absolute encoder. It is not used to measure the rotation angle detection or rotation speed detection of the rotating device. To measure the amount of axial deflection or radial deflection of a rotating shaft in the rotating device, if you want to measure the amount of deflection, you must also install an eddy current sensor for detection. Therefore, improving the structure of the existing magnetic encoder is a problem to be solved by those skilled in the art.

Therefore, an object of the present invention is to provide a magnetic encoder for measuring the deviation of a rotating shaft.

Therefore, the magnetic encoder for measuring the deflection of the rotating shaft of the present invention includes a ring-shaped base body and a magnetic encoding unit.

The annular base body is made of a magnetically permeable material and includes a first surface and a second surface opposite to the first surface.

The magnetic encoding unit is disposed on one of the first surface and the second surface of the annular base, and includes a plurality of first magnetic poles and second magnetic poles that are staggered in a concentric circle with a central axis of the annular base.

In addition, the present invention also provides a magnetic encoding device, which is suitable for being mounted on a rotating shaft for measuring the yaw of the rotating shaft. The magnetic encoding device includes the aforementioned magnetic encoder and a sensor.

The encoder is arranged around the rotation axis. The sensor is disposed at a distance from the magnetic encoder corresponding to the magnetic encoding unit.

The effect of the present invention is that the first magnetic poles and the second magnetic poles are staggered in a concentric circle distribution, and it is not necessary to set a neutral isolation ring to block the interference of adjacent magnetic poles as in the existing encoder, and the energy can measure the axis of the rotating shaft Amount of yaw and radial yaw.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are represented by the same numbers.

Referring to FIG. 1 and FIG. 2, a first embodiment of a magnetic encoder 2 for measuring a rotation axis deviation according to the present invention includes an annular base 21, a magnetic encoding unit 22 formed on the annular base 21, and a magnetic encoder unit 22 disposed on the annular base 21. The fixing member 23 of the annular base body 21, wherein FIG. 2 is a partial enlarged view of the magnetic encoding unit 22 and the fixing member 23 of FIG. 1.

Specifically, the annular base 21 is made of a magnetically permeable material and includes a central axis 200, a first surface 211, a second surface 212 opposite the first surface 211, and an inner portion adjacent to the central axis 200. Perimeter 213. The magnetic encoding unit 22 is formed on the first surface 211 of the annular base 21 and includes a plurality of first magnetic poles N and second magnetic poles S arranged in a concentric circle with the central axis 200 of the annular base 21 as a concentric circle.

In detail, in the first embodiment, the annular base 21 is flat, that is, a normal n between the first surface 211 and the second surface 212 is parallel to the central axis 200 such that The boundary line 220 between the first magnetic pole N and the second magnetic pole S is arranged along a radial direction of the annular base 21. The number of the first magnetic pole N and the second magnetic pole S is not particularly limited, and the number of the first magnetic pole N and the second magnetic pole S may be reduced or increased according to application requirements.

The fixing member 23 is disposed on the inner peripheral edge 213, so that the annular base 21 can be more conveniently mounted on other devices in the subsequent steps. It should be noted that the appearance of the fixing member 23 is not particularly limited, and the fixing member 23 may not be provided according to circumstances, as long as the annular base 21 can be mounted on a device to be applied.

Referring to FIG. 3 and FIG. 4, a second embodiment of the magnetic encoder 2 for measuring the rotation axis deviation according to the present invention is substantially the same as the first embodiment, except that the annular base 21 of the second embodiment Appearance. Specifically, FIG. 4 is a partially enlarged view of the magnetic encoding unit 22 of FIG. 3. In the second embodiment, the annular base 21 is a three-dimensional annular shape, that is, the first surface 211 and the second surface The normal n of the surface 212 is perpendicular to the central axis 200, and the second surface 212 is adjacent to the central axis 200, so that the magnetic encoding unit 22 is disposed on the first surface 211 on the periphery, and the first magnetic pole The boundary line 220 between N and the second magnetic pole S is arranged along an axial direction of the annular base body 21 (that is, along the direction of the central axis 200). When the magnetic encoder 2 of the second embodiment is to be mounted with the fixing member 23, it is mounted on the second surface 212.

According to the magnetic encoder 2 of the present invention, the first magnetic poles N and the second magnetic poles S are staggered in a concentric circle distribution, and the axial and radial deflections of the rotating shaft are measured. In detail, the magnetic pole writing direction of the magnetic encoder 2 of the first implementation is penetrated by a normal line n of the first magnetic pole N (that is, a direction parallel to the central axis 200) and then enters the second magnetic pole S ; And the magnetic pole writing direction of the magnetic encoder 2 of the second embodiment passes through the normal line n of the first magnetic pole N (that is, a direction perpendicular to the central axis 200) and then enters the second magnetic pole S.

In order to explain more clearly how to measure the axial and radial deflections of the rotating shaft with the magnetic encoder 2 of the first embodiment and the second embodiment, a method including the aforementioned magnetic encoder 2 is proposed below. The magnetic encoder will be described.

Referring to FIG. 5, the magnetic encoding device is adapted to be mounted on a rotating shaft 4 to perform a yaw measurement of the rotating shaft 4. In FIG. 5, the magnetic encoding device is based on the magnetism including the first embodiment. The encoder 2 and a sensor 3 are described as examples. Specifically, the magnetic encoder 2 is disposed around the rotation axis 4, and the sensor 3 is disposed at a distance from the magnetic encoder 2 corresponding to the magnetic encoding unit 22.

In detail, since the normal n between the first surface 211 and the second surface 212 of the magnetic encoder 2 of the first embodiment is parallel to the central axis 200 (see FIG. 1), the magnetic encoding When the device 2 is mounted on the rotating shaft 4, the inner peripheral edge 213 (see FIG. 2) of the annular base 21 is oriented toward the rotating shaft 4 and is fixed on the rotating shaft 4 through the fixing member 23. The sensor 3 is mounted on the fixed side in a non-contact manner to sense the magnetic coding unit 22, and the mounting method is not particularly limited, as long as it is spaced from the magnetic coding unit 22. The sensor 3 suitable for use in the present invention may be selected from magnetic sensors such as a magnetoresistive or Hall sensor, and is not particularly limited.

Referring to FIGS. 6 and 7, when the magnetic encoding device is mounted on the rotating shaft 4 with the magnetic encoder 2 of the second embodiment, it is the second surface 212 of the annular base 21 (see FIG. 3) It is disposed toward the rotation shaft 4 and is also fixed on the rotation shaft 4 through the fixing member 23, so that the magnetic encoding unit 22 is a surface 41 facing away from the rotation shaft 4, and the sensor 3 is also It is spaced from the magnetic encoding unit 22. It should be particularly noted here that, because the normal n between the first surface 211 and the second surface 212 of the magnetic encoder 2 of the second embodiment is perpendicular to the central axis 200 (see FIG. 3), Alternatively, the fixing member 23 may not be provided, and the second surface 212 of the magnetic encoder 2 may be directly attached to the surface 41 of the rotating shaft 4 as shown in FIG. 7.

With reference to FIG. 8, the installation and calculation process of measuring the axial and radial deflections of the rotating shaft 4 by using the magnetic encoding device of FIG. 5 or FIGS. 6 and 7 is further described here. First, because the amount of eccentricity has a great influence on the rotational motion, the concentricity of the magnetic encoder 2 and the rotary shaft 4 is first corrected.

Next, when the rotary shaft 4 performs a rotational movement, when the magnetic encoder device (see FIG. 5) having the magnetic encoder 2 of the first embodiment is used for measurement, it can be sensed by the sensor 3. The magnetic encoding unit 22 outputs a voltage signal due to a change in the magnetic field distribution of the rotation axis 4 in the radial deflection (ie, the x direction in FIG. 5), and transmits the voltage signal to a sensor 3 connected to the sensor 3. A micro-controller unit (MCU) (not shown) performs calculation and analysis to obtain the radial deflection of the rotating shaft 4 during the rotation process; and when the magnetic encoding with the second embodiment is used, When the magnetic encoding device (see Figs. 6 and 7) of the device 2 performs measurement, the magnetic encoding unit 22 can be sensed by the sensor 3 due to the axial deflection of the rotating shaft 4 (i.e. The y-direction of 7) changes the magnetic field distribution and outputs a voltage signal, and transmits this voltage signal to the microcontroller (MCU) (not shown) for calculation and analysis. Axial deflection.

In summary, the magnetic encoder for measuring the deflection of the rotating shaft of the present invention allows the annular base 21 to be flat (such as the first embodiment) or three-dimensional (such as the second embodiment). The first magnetic poles N and the second magnetic poles S on the base body 21 are staggered in a concentric circle distribution. It is not necessary to set a neutral isolation ring to block the interference of adjacent magnetic poles as in the existing encoder, and the energy can measure the axial direction of the rotating shaft 4 The amount of yaw and radial yaw can indeed achieve the purpose of the invention.

However, the above are only examples of the present invention. When the scope of implementation of the present invention cannot be limited by this, any simple equivalent changes and modifications made according to the scope of the patent application and the contents of the patent specification of the present invention are still Within the scope of the invention patent.

2‧‧‧ magnetic encoder

23‧‧‧Fixed parts

200‧‧‧ center axis

3‧‧‧Sensor

21‧‧‧ ring base

4‧‧‧rotation axis

211‧‧‧first surface

41‧‧‧ surface

212‧‧‧Second Surface

N‧‧‧first magnetic pole

213‧‧‧Inner periphery

S‧‧‧Second magnetic pole

22‧‧‧ Magnetic Encoding Unit

n‧‧‧normal

220‧‧‧Boundary

Other features and effects of the present invention will be clearly presented in the embodiment with reference to the drawings, in which: FIG. 1 is a schematic three-dimensional diagram illustrating a first embodiment of the magnetic encoding for measuring the rotation axis deviation of the present invention; FIG. 2 is a partially enlarged schematic diagram illustrating a magnetic encoding unit according to the first embodiment of the present invention; FIG. 3 is a schematic three-dimensional diagram illustrating a second embodiment of the magnetic encoding for measuring the rotation axis deviation of the present invention; FIG. 5 is a partially enlarged schematic view illustrating the magnetic coding unit of the second embodiment of the present invention; FIG. 5 is a schematic perspective view illustrating the first embodiment of the present invention and a sensor mounted on a rotation axis; 6 is a schematic perspective view illustrating the second embodiment of the present invention and a state in which the sensor is mounted on the rotation axis; FIG. 7 is a schematic perspective view illustrating the second embodiment of the present invention and the sensing Another aspect of the device mounted on the rotating shaft; and FIG. 8 is a flowchart illustrating the flow of measuring the rotation of the rotating shaft by the magnetic encoding device of the present invention.

Claims (10)

A magnetic encoder for measuring the deflection of a rotating shaft includes: a ring-shaped base body made of a magnetically conductive material, including a first surface and a second surface opposite to the first surface; and a magnetic encoding unit provided on One of the first surface and the second surface of the annular base includes a plurality of first magnetic poles and second magnetic poles that are staggered with a central axis of the annular base as a concentric circle. The magnetic encoder for measuring the rotation axis deviation according to claim 1, wherein a normal line between the first surface and the second surface is parallel to the central axis, and the magnetic encoding unit is disposed on the first surface, The boundary line between the first magnetic pole and the second magnetic pole is arranged along a radial direction of the annular base body. The magnetic encoder for measuring deflection of a rotating shaft according to claim 2, further comprising a fixing member disposed on an inner peripheral edge of the annular base body. The magnetic encoder for measuring the rotation axis deviation according to claim 1, wherein a normal line between the first surface and the second surface is perpendicular to the central axis, and the second surface is adjacent to the central axis, and The magnetic encoding unit is disposed on the first surface, and an interface between the first magnetic pole and the second magnetic pole is arranged along an axial direction of the annular base body. The magnetic encoder for measuring the rotation axis deviation according to claim 4, further comprising a fixing member disposed on the second surface of the annular base. The magnetic encoder for measuring the rotation axis deviation according to claim 1, wherein the first magnetic pole and the second magnetic pole are an N pole and an S pole, respectively. A magnetic encoding device is adapted to be mounted on a rotating shaft for measuring the deviation of the rotating shaft. The magnetic encoding device comprises: a magnetic encoding for measuring the deviation of a rotating shaft according to claims 1 to 6 An encoder arranged around the rotation axis; and a sensor arranged at a distance from the magnetic encoder corresponding to the magnetic encoding unit. The magnetic encoding device according to claim 7, wherein when a normal line of the first surface and the second surface of the magnetic encoder is parallel to the central axis, an inner peripheral edge of the annular base faces the rotation axis. The magnetic encoding device according to claim 7, wherein when a normal line between the first surface and the second surface is perpendicular to the central axis, the second surface of the annular substrate faces the rotation axis. The magnetic encoding device according to claim 9, wherein the magnetic encoder is attached to a surface of the rotating shaft with the second surface.