JPH04110917U - Magnetoelectric conversion type rotation angle detection device - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the detection ability of the sensor and to facilitate its assembly by making it possible to waveform shape the output signal of a magnetoelectric transducer (sensor) using both magnetic field methods. [Structure] An AB phase magnetized zone 3 and a Z phase magnetic zone 7 are formed on a magnetized ring 2 mounted on a rotor 1. Z-phase magnetic belt 7 is 1
It consists of two reference magnetic poles and a background of opposite polarity connected to both ends of the reference magnetic poles. The AB phase polarized magnetic belt 3 has a plurality of magnetic poles having different polarities arranged alternately. An intermediate magnetized zone 8 having the same polarity as the background is provided between the AB phase magnetic zone 3 and the Z phase magnetic zone 7. The electrical signal output from the Z-phase sensor 6 has a change point only at the boundary between the reference magnetic pole and the background. Therefore, even if waveform shaping is performed using both magnetic field methods, the reference point for rotation angle detection can be easily recognized. Further, according to the waveform shaping of the dual magnetic field method, the detection ability is improved and the gap between the sensor 6 and the magnetized belt 7 can be easily adjusted.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a magneto-electric conversion type rotation angle detection device, and is particularly applicable to rotation angle detection devices. Concerning a magneto-electric conversion type rotation angle detection device that improves the well-known magnetized band applied to a rotating body. It is something that

0002

[Conventional technology]

Figure 5 is a perspective view showing an example of a conventional magneto-electric conversion type rotation angle detection device and an enlarged view of its main parts. It's a big picture. In the same figure, it is attached to a rotating body (not shown) that is the object to be detected for the rotation angle. A magnetizing ring 2 is fitted onto the end of the rotor 1 to provide desired magnetization. Ru. The magnetized ring 2 has an A magnet with N and S poles alternately magnetized around its entire circumference. B-phase magnetized belt 3 and a magnetized ring with either N pole or S pole sandwiched between the other pole. A Z-phase magnetized zone 4 is provided in a part of the magnetic field 2.

0003 Magnetoelectric transducers 5 and 6 are arranged with a predetermined gap on the outer peripheral surface of the magnetized ring 2. is installed. One magnetoelectric conversion element 5 (hereinafter referred to as AB phase sensor 5) is A The other magnetoelectric change element 6 (hereinafter referred to as Z-phase sensor) (referred to as "sa") is arranged at a position facing the Z-phase magnetized belt 4.

0004 The AB phase sensor 5 detects the AB phase as the rotor 1 rotates in the direction of the arrow 11. It receives magnetic action alternately from the north and south poles of the magnetic belt 3, and outputs a sine wave signal. child The sine wave signal is supplied to a waveform shaping means (not shown) and shaped into a rectangular wave signal. The rotation angle of the rotor 1 can be detected by counting the number of pulses of the square wave signal. I can do that.

[0005] Similarly, the Z-phase sensor 6 also outputs a sine wave signal due to the effect of the magnetic field from the Z-phase magnetized belt 4. Ru. However, in this case, the magnetized ring is not magnetized all the way around it, but only a part of it is magnetized. Therefore, a sine wave signal is not output continuously. In other words, once for rotor 1 A sine wave signal is generated only at the position where the Z-phase magnetized part 4 and the Z-phase sensor 6 face each other regarding rotation. The number will be output. In this way, the sine wave signal is output only within a limited range. Therefore, based on this signal, the position of the rotor 1 during one rotation can be specified, This position can be used as a reference point for rotation angle detection. In addition, as shown in Fig. 5(b) In this conventional device, the Z-phase magnetized belt 4 is arranged so that the S pole is sandwiched between the N poles. On the other hand, there is also an arrangement in which the north pole is sandwiched between the south poles.

[0006]

[Problem that the idea aims to solve]

The conventional magneto-electric conversion type rotation angle detection device described above has the following problems. Figure 6 shows the output signal waveform of the Z-phase sensor 6 obtained by a conventional magneto-electric conversion type rotation angle detection device. shows. In the figure, the sine wave signal SW has a threshold value Thn on the north pole side and a threshold value Thn on the south pole side. The pulse is shaped according to the threshold Ths and converted into a rectangular wave signal PW. This way In other words, a method for shaping the waveform by setting thresholds on both sides of the N and S poles is applied to both magnetic fields. It's called a ceremony.

[0007] In this dual magnetic field method, as shown in the figure, the Z-phase sensor obtained by the Z-phase magnetized belt 4 In the waveform of the output signal of No. 6, two points of change from off to on appear at S1 and S2. Ru. The detection device that detects the rising edge of the rectangular wave signal PW and recognizes the rotation reference In the square wave PW where a sudden change point S1 appears, it becomes difficult to recognize the rotation reference, and the processing circuit The problem was that it became complicated.

[0008] In order to prevent such a change point S1 from appearing, thresholds Thn and Both Ths may be set to the south pole side. In this way, set the threshold to one side. The method of shaping the waveform by setting it on the magnetic pole side is called the single-field method. In this single magnetic field method, the width of the sine wave signal SW cannot be used effectively, so the Z-phase High precision is required for adjusting the gap between the sensor 6 and the magnetized ring 2. It also maintains high accuracy. If this is not possible, increase the magnetic force of the Z-phase magnetic belt 4 and increase the amplitude of the sine wave signal SW. I have to comb it.

[0009] In order to accurately adjust the gap between the Z-phase sensor 6 and the magnetized ring 2, it is necessary to This may require additional time or a jig for adjustment. On the other hand, the Z-phase magnetic belt 4 If the magnetic force is strengthened, it will affect the AB phase magnetized zone 3, so the individual magnetic poles of the AB phase magnetic zone 3 will be There also arises the problem that it is not possible to make the image smaller, that is, the resolution is reduced.

0010 In this way, there are many advantages to shaping the output waveform of the Z-phase sensor 6 using both magnetic field methods. However, as mentioned above, conventional magnetized belts have the problem that both magnetic field methods cannot be used. It was.

[0011] The purpose of this invention is to solve the above-mentioned problems and to make it easier to process sensor output and to make installation adjustments easier. Magnetoelectric conversion that allows the output waveform of the Z-phase sensor 6 to be shaped using both magnetic field methods without complication An object of the present invention is to provide a rotation angle detection device based on the above-described method.

0012

[Means to solve the problem]

In order to solve the above problems, the present invention provides one reference magnetic pole and this reference magnetic pole. A ring consisting of a background magnetic pole connected to both ends of the pole and of opposite polarity to the reference magnetic pole. A Z-phase magnetized belt with a shape, and an annular AB-phase magnetized belt with magnetic poles of different polarities arranged alternately. , an annular magnetic body provided between the Z phase magnetized zone and the AB phase magnetic zone; a Z-phase sensor for rotation reference detection disposed opposite to the complementary magnetic belt; and the AB complementary magnetic belt. and an AB phase sensor for rotational angle detection disposed opposite to each other. The magnetic belt is characterized in that it is arranged along the rotation direction of the object whose rotation angle is to be detected.

[0013]

[Effect]

Even when the output waveform of the Z-phase sensor is shaped using both magnetic field methods, the output waveform of the Z-phase sensor is There is only one change point from off to on per cycle, namely the reference magnetic pole and the background. Since it only appears on one side of the boundary with the magnetic pole, the rotation angle detection is based on this change point. Quasi-points can be easily recognized. In addition, a ring provided between the AB magnetized zone and the Z phase magnetized zone The magnetic force of the Z-phase magnetized zone influences the magnetic field formed by the AB-phase magnetic zone due to the shaped magnetic body. It can prevent spills.

[0014]

【Example】

The present invention will be described in detail below with reference to the drawings. Figure 1 shows an example of the present invention. 5 is a perspective view and an enlarged view of the main parts of the magneto-electric conversion type rotation angle detection device shown in FIG. Codes indicate the same or equivalent parts. In the same figure, in the circumferential direction of the magnetized ring 2 attached to the rotor 1, there are A magnetic belt 3 and a Z-phase magnetic belt 7 are provided. The AB phase polarized magnetic belt 3 has many N poles and This is a magnetized belt in which the and S poles are arranged alternately to form an annular shape. On the other hand, Z-phase magnetic belt 7 is the S pole, which is the reference magnetic pole, and the S pole, which is continuous with this reference magnetic pole and is the background magnetic pole. This is a magnetized belt that forms an annular shape with the N pole.

[0015] In this embodiment, the size of the S pole, which is the reference magnetic pole of the Z-phase magnetized belt 7, that is, the Z-phase polarization The annular direction (longitudinal direction) dimension l of the magnetic belt is the size of one magnetic pole of the AB compatible magnetic belt 3. It is set almost the same as , but this can be set arbitrarily. In short, the rotation of the Z-phase magnetic belt 7 The annular region along the rotation direction of the trochanter 1, that is, a part of the circumferential region of the rotor 1 is set as the N pole. Alternatively, magnetize with the S-pole reference magnetic pole, and use magnetic poles of opposite polarity on both sides of this reference magnetic pole. It is sufficient that connected background magnetic poles are formed. Between the AB phase magnetized zone 3 and the Z phase magnetic zone 7, there is an intermediate magnetized zone adjacent to the Z phase magnetic zone 7. A band 8 is formed. This intermediate magnetized belt 8 has the same polarity as the reference magnetic pole, that is, S It is magnetized to the pole.

[0016] Next, the effect of the magnetic field of the AB-phase magnetized belt 3 and the Z-phase magnetized belt 7 that have been magnetized as described above will be explained. 3 shows the waveforms of the signals output from the AB phase sensor 5 and the Z phase sensor 6. 2 is a diagram showing the signal waveform output from the Z-phase sensor 6, and FIG. 3 is a diagram showing the signal waveform output from the Z-phase sensor 6. 5 is a diagram showing a signal waveform output from the sensor 5. FIG. In Figs. 2 and 3, the amount indicated as “one rotation” is due to one rotation of rotor 1. This is a signal output from the AB phase sensor 5 and the Z phase sensor 6. in this way, The signal changes from off to on only once during one revolution of the rotor 1.

[0017] Note that the waveform SWd shown by the chain line in FIG. This is the output waveform of the AB phase sensor 5 when As shown in the figure, an intermediate magnetized zone 8 is provided. If the AB phase sensor 5 The number of magnetic fluxes at the N pole of the AB complementary magnetic belt 3 that acts on the magnetic field decreases, and conversely, the number of magnetic fluxes at the S pole increases. As a result, the midpoint of the waveform shifts toward the south pole. In this way, the background magnetic The poles are provided to eliminate any influence on the output of the AB phase sensor.

[0018] In the embodiment described above, the magnetized ring 2 has each magnetized band attached to the circumference of the rotor 1. The magnet is formed on the rotor 1 or the object to be detected at the rotation angle is directly magnetized. It's okay. In addition, the magnetized position is not limited to the circumference of the rotor 1 or the magnetized ring 2, but also Depending on the shape and size of the body, it may be provided on other surfaces of the rotor 1 or the object to be detected. sand In other words, it is better if the magnetized band is formed along the rotation direction of the rotating body that is the object to be detected. stomach.

[0019] FIG. 4 shows an AB phase magnetic zone 3, a Z phase magnetic zone 7, and an intermediate magnetic zone on the end face of the object to be detected. This is an example in which a magnetized band 8 is formed. In the figure, the detected object 9 is in the direction of the arrow 11. It is a rotating object, and its end face 10 has annular magnetized bands 3, 7, and 8 with different diameters. each formed.

[0020] Note that instead of being actively magnetized, the intermediate magnetized zone 8 is made of a ring-shaped magnetic material such as iron. The same effects as in this embodiment can also be obtained by forming a shield region.

[0021]

[Effect of the idea]

As is clear from the above explanation, according to the present invention, Z-phase separation is achieved using both magnetic field methods. Even if the output of the sensor is shaped, the basis of rotation is Quasi-points can be easily recognized. Therefore, both magnetic field methods can be used and The magnetic field of the magnetic belt can be effectively applied to the sensor. As a result, the Z phase sensor Detection ability is increased and installation tolerances can be relaxed.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a rotation angle detection device showing an embodiment of the present invention.

FIG. 2 is a diagram showing an output waveform of a Z-phase sensor.

FIG. 3 is a diagram showing an output waveform of an AB phase sensor.

FIG. 4 is a perspective view of a rotation angle detection device showing a second embodiment.

FIG. 5 is a perspective view of a rotation angle detection device showing a prior art.

FIG. 6 is a diagram showing an output waveform of a conventional Z-phase sensor.

[Explanation of symbols]

1... Rotor, 2... Magnetized ring, 3... AB complementary magnetized belt,
4, 7...Z phase magnetized belt, 8...Intermediate magnetized belt, 9...Detected object

──────────────────────────────────────────────── ─── Continuation of front page (72) Creator Hiroshi Furukai 1-4-1 Chuo, Wako City, Saitama Prefecture Co., Ltd. Inside Honda Technical Research Institute

Claims (3)

[Scope of utility model registration request] Claim 1: The object to be detected has a magnetized band in which magnetic poles are arranged alternately, and the rotating body is rotated based on an electric signal output from a magnetoelectric transducer due to the magnetic action of the magnetized band. In a magneto-electric conversion type rotation angle detection device that detects an angle, an annular Z-phase magnetized band consisting of a reference magnetic pole and a background magnetic pole connected to both ends of the reference magnetic pole and having a polarity opposite to that of the reference magnetic pole, and an annular AB phase magnetized zone formed by alternately arranging magnetic poles; an annular magnetic body provided between the Z phase magnetized zone and the AB phase magnetized zone;
A Z-phase sensor for rotation reference detection disposed facing the mutually magnetized belt, and an AB phase sensor for rotational angle detection disposed facing the AB phase magnetized belt, and each of the above-mentioned A magneto-electric conversion type rotation angle detection device characterized in that the magnetized belt is arranged along the rotation direction of an object whose rotation angle is to be detected. 2. The reference magnetic pole of the Z-phase magnetized zone has a longitudinal dimension of the magnetized zone that is equal to or smaller than the dimension in the same direction of each magnetic pole of the AB-phase magnetized zone. The magneto-electric conversion type rotation angle detection device described above. 3. The magnetoelectric conversion type rotation angle detection device according to claim 1, wherein the annular magnetic body is a magnetized band having the same polarity as the reference electrode.