Redundant Encoders

Abstract

An encoder capable of detecting both the rotation angle within one rotation and the amount of multiple rotations with redundancy. [Solution] A redundant encoder 100 includes a magnetic field generating unit 5 having two or more north poles 2 and two or more south poles 3, a first rotation detecting unit 10 that detects the amount of rotation with a resolution of 1 / 2 rotation or less, and a second rotation detecting unit 20 that detects the amount of rotation with a higher resolution than the first rotation detecting unit 10. A permanent magnet is used for the magnetic field generating unit 5. The first rotation detecting unit 10 includes a magnetic generating element having the large Barkhausen effect, and a magnetic detecting element having the Hall effect or magnetoresistance effect.

Description

[Technical field]

[0001] The present invention relates to a redundant encoder, and more particularly to a technique for improving the reliability of detecting a rotation angle within one rotation and an amount of multiple rotations. [Background technology]

[0002] FIG. 7 is an explanatory diagram showing the configuration and main points of operation of a conventional encoder having one rotation angle detection unit disclosed in Patent Document 1 below. As shown in the figure, this encoder 700 is composed of a single rotation detection unit 720, which detects the rotation angle within one rotation, and the amount of multiple rotations is detected from the integrated amount. The output signal from the rotation detection unit 720 is sent to a signal processing circuit 728, which obtains the rotation angle within one rotation. The resolution is, for example, 1 / 4096 rotation or less. The rotation detection unit 720 and the signal processing circuit 728 are supplied with power from an external power source 729.

[0003] FIG. 8 is an explanatory diagram showing the configuration and the main points of the operation of a conventional encoder having two rotation detectors disclosed in Patent Document 2. As shown in the figure, this encoder 800 is configured with a total of two rotation detectors, a second rotation detector 820 that detects the rotation angle within one rotation, and a first rotation detector 810 that detects the amount of multiple rotations. Therefore, the second rotation detector 820 detects the rotation angle within one rotation, while the first rotation detector 810 detects the amount of multiple rotations. An output signal from the second rotation detector 820 is sent to a second signal processing circuit 828, which obtains the rotation angle within one rotation. The resolution is, for example, 1 / 4096 rotation or less. The second rotation detector 820 receives power from an external power source 829.

[0004] The first rotation detection unit 810 is composed of a magnetic power generation element 86, a magnetic detection element 87 having a Hall effect or a magnetoresistance effect, and a magnetic field generation unit 85 having a north pole and a south pole. The magnetic field generation unit 85 is provided coaxially with the second rotation detection unit 820, and the magnetic power generation element 86 generates power by the generated magnetic field, and the magnetic field change due to rotation is detected by the magnetic detection element 87. An output signal from the magnetic detection element 87 is sent to a first signal processing circuit 818, which detects the amount of multiple rotations. The resolution is 1 / 1 rotation or less. The first rotation detection unit 810 does not have an external power supply. An output voltage from the magnetic power generation element 86 is supplied to the first signal processing circuit 818.

[0005] In this encoder 800, when power is being supplied from the external power source 829, the rotation angle within one rotation is detected with the resolution of the second rotation detection unit 820. For example, this is 1 / 4096 rotation or less. Meanwhile, the amount of multiple rotations is not only detected by the first rotation detection unit 810, but is also obtained from the integrated amount of the rotation angles within one rotation detected by the second rotation detection unit 820. In other words, the amount of multiple rotations is detected with redundancy. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Jpn.Publication No. 02-97619 "Multi-rotation absolute value encoder" [Patent Document 2] JP 2014-137233 A "Motor" Summary of the Invention [Problem to be solved by the invention]

[0007] Encoder 700, which has a single rotation detection unit, cannot detect the rotation angle within one rotation and the amount of multiple rotations with redundancy. Encoder 800, which has two rotation detection units, can detect the amount of multiple rotations with redundancy, but cannot detect the rotation angle within one rotation with redundancy. Therefore, both of the conventional technologies have limitations in terms of improving the reliability of detection.

[0008] The problem that the present invention aims to solve is to provide an encoder that eliminates the problems of the prior art and is capable of detecting both the rotation angle within one rotation and the amount of multiple rotations with redundancy. [Means for solving the problem]

[0009] The inventors of the present application have studied the above problem. Based on the fact that the first rotation detection section in the conventional encoder consisting of the above two rotation detection sections is composed of only one N pole and one S pole, which is the reason for the lack of redundancy, they have found that this problem can be solved by making the magnetic field generating section have two or more N poles and two or more S poles, and have completed the present invention based on this. That is, the invention claimed in this application as a means for solving the above problem, or at least the invention disclosed therein, is as follows.

[0010] [1] A redundant encoder comprising: a first rotation detection unit having a magnetic field generating unit having two or more north and south poles and detecting the amount of rotation with a resolution of 1 / 2 rotation or less; and a second rotation detection unit detecting the rotation angle with a higher resolution than the first rotation detection unit, thereby providing redundancy in both the rotation angle within one rotation and the amount of multiple rotations. [2] The redundant encoder according to [1], characterized in that the first rotation detection unit includes a magnetic generating element having a large Barkhausen effect and a magnetic detection element having a Hall effect or a magnetoresistance effect. [3] A redundant encoder as described in [2], characterized in that it comprises a first signal processing circuit that processes an output signal from the first rotation detection unit, and a second signal processing circuit that processes an output signal from the second rotation detection unit. [4] The redundant encoder according to [3], wherein the second rotation detection unit and the second signal processing circuit are provided with an external power supply.

[0011] [5] A redundant encoder according to any one of [1], [2], [3], and [4], characterized in that the second rotation detection unit is an optical, magnetic, electromagnetic induction, capacitive, or other type of rotation detector. [6] The redundant encoder according to any one of [1], [2], [3], and [4], characterized in that the resolution of the second rotation detection unit is 1 / 4096 rotation or less. [7] A redundant encoder as described in any one of claims 1, 2, 3, and 4, characterized in that a rotation angle T1s within one rotation with a resolution of ½ rotation or less is detected from the rotation amount T1 obtained by the first rotation detection unit, and a multiple rotation amount T1m is detected by integrating the rotation amount T1, and a rotation angle T2s within one rotation with a higher resolution than that obtained by the first rotation detection unit is detected from the rotation angle T2 obtained by the second rotation detection unit, and the multiple rotation amount T2m is detected by integrating the rotation angle T2. [8] The redundant encoder according to [7], characterized in that by comparing the rotation angle T1s and the rotation angle T2s, the rotation angle within one rotation is detected with redundancy that matches to a resolution of 1 / 2 rotation or less, and by comparing the multi-rotation amount T1m and the multi-rotation amount T2m, the multi-rotation amount is detected with redundancy that matches to the resolution of one rotation.

[0012] [9] The device includes a first signal processing circuit for processing an output signal from the first rotation detection unit, and a second signal processing circuit for processing an output signal from the second rotation detection unit, A second rotation detector and Applicable The second signal processing circuit is provided with an external power supply; Applicable The redundant encoder according to [7], characterized in that the resolution of the second rotation detection unit is 1 / 4096 rotation or less, and by comparing the rotation angle T1s and the rotation angle T2s, the rotation angle within one rotation is detected to 1 / 4096 rotation or less, which is the resolution of the rotation angle T2, and is detected with redundancy up to 1 / 2 rotation or less, which is the resolution of the rotation amount T1, and by comparing the multi-rotation amount T1m and the multi-rotation amount T2m, the multi-rotation amount is detected with redundancy that matches up to the resolution of one rotation. Effect of the Invention

[0013] Since the redundant encoder of the present invention is configured as described above, it is possible to detect both the rotation angle within one rotation and the amount of multiple rotations with redundancy, thereby improving the reliability of detection. Furthermore, the amount of multiple rotations can be detected regardless of the presence or absence of an external power source or whether the external power source is operating or not. In other words, although the second rotation detection unit is equipped with an external power source, even if a malfunction occurs in this, the amount of multiple rotations can be detected up to a resolution of one rotation by the first rotation detection unit, which has a resolution of 1 / 2 rotation or less. [Brief description of the drawings]

[0014] [Figure 1] FIG. 2 is an explanatory diagram showing the basic configuration of a redundancy encoder of the present invention; [Diagram 2] 5A to 5C are explanatory diagrams showing the configuration and operation of a redundant encoder of the present invention in which a first rotation detection unit is provided with a magnetic generating element or the like. [Diagram 3] FIG. 2 is an explanatory diagram showing the configuration and operation of a redundancy encoder of the present invention having a signal processing circuit; [Figure 4] FIG. 4 is an explanatory diagram showing the rotation detection function in the redundant encoder of the present invention. [Diagram 5] FIG. 11 is a second explanatory diagram showing the rotation detection function in the redundant encoder of the present invention. [Figure 6] FIG. 2 is an explanatory diagram showing the configuration of an embodiment of a redundancy encoder of the present invention; [Figure 7] 1 is an explanatory diagram showing the configuration and operation of a conventional encoder having one rotation angle detection unit. [Figure 8] 1 is an explanatory diagram showing the configuration and operation of a conventional encoder having two rotation angle detection units. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The present invention will now be described in detail with reference to the drawings. 1 is an explanatory diagram showing the basic configuration of a redundant encoder of the present invention. As shown in the figure, this redundant encoder 100 is mainly composed of a magnetic field generating unit 5 having two or more north poles 2 and two or more south poles 3, a first rotation detecting unit 10 that detects the amount of rotation of a detection object with a resolution of 1 / 2 rotation or less, and a second rotation detecting unit 20 that detects the amount of rotation of the same detection object with a higher resolution than the first rotation detecting unit 10. A permanent magnet can be used for the magnetic field generating unit 5.

[0016] In this redundant encoder 100, the magnetic field generating unit 5 of the first rotation detection unit 10 has two or more north poles 2 and two or more south poles 3, and therefore detects the amount of rotation with a resolution of 1 / 2 rotation or less. In other words, this allows the amount of multiple rotations to be detected, and also allows the rotation angle within one rotation to be detected with a resolution of 1 / 2 rotation or less. On the other hand, the second rotation detection unit 20 has a higher resolution than the first rotation detection unit 10, and therefore allows the rotation angle within one rotation to be detected with higher accuracy than the first rotation detection unit 10, and also allows the amount of multiple rotations to be detected by integrating the detection results (rotation angle). Therefore, according to this redundant encoder 100, detection with redundancy can be performed for both the rotation angle within one rotation and the amount of multiple rotations.

[0017] The total number of north poles 2 and south poles 3 in the magnetic field generating unit 5 of the redundant encoder 100 of the present invention is four or more, and the more poles there are, such as six or eight, the better the resolution. However, the desired effect of the present invention can be sufficiently obtained with two north poles 2 and two south poles 3, a total of four poles.

[0018] 2 is an explanatory diagram showing the configuration and operation of a redundant encoder of the present invention in which a first rotation detection unit is equipped with a magnetic power generation element, etc. As shown in the figure, in this redundant encoder 2100, the first rotation detection unit 210 can be configured to include a magnetic field generating unit 25 having two or more N poles 22 and S poles 23, as well as a magnetic power generation element 26 having the large Barkhausen effect and a magnetic detection element 27 having the Hall effect or magnetoresistance effect.

[0019] The magnetic field generating unit 25 is provided coaxially with the second rotation detecting unit 220 . The magnetic field generated by the magnetic field generating unit 25 causes the magnetic generating element 26 to generate power, and the magnetic field change due to rotation is detected by the magnetic detecting element 27 .

[0020] 3 is an explanatory diagram showing the configuration and operation of a redundant encoder of the present invention equipped with a signal processing circuit. As shown in the figure, this redundant encoder 3100 can be configured to include a first signal processing circuit 318 that processes an output signal from a first rotation detection unit 310, and a second signal processing circuit 328 that processes an output signal from a second rotation detection unit 320, in addition to the configuration shown in FIGS.

[0021] According to the redundant encoder 3100 having such a configuration, the output signals from the magnetic generating element 36 and the magnetic detecting element 37 of the first rotation detecting unit 310 are sent to the first signal processing circuit 318, where they are processed to detect the amount of multiple rotations T1. Also, since the magnetic field generating unit 35 has two or more north poles 32 and two or more south poles 33, the resolution is ½ rotation or less. Therefore, the rotation angle within one rotation can also be detected with a resolution of ½ rotation or less. The first rotation detecting unit 310 does not have an external power supply. The output voltage from the magnetic generating element 36 is supplied to the first signal processing circuit 318.

[0022] On the other hand, the output signal from the second rotation detection unit 320 is sent to a second signal processing circuit 328, where it is processed to detect a rotation angle T2 within one rotation. The resolution of the second rotation detection unit 320 can be, for example, 1 / 4096 rotation or less, but is not limited to this.

[0023] As shown in the figure, the second rotation detection unit 320 and the second signal processing circuit 328 of the present redundant encoder 3100 are configured to be equipped with an external power supply 329. In the present encoder 3100, while power is being supplied from the external power supply 329, the rotation angle T2 within one rotation is detected with the resolution of the second rotation detection unit 320. For example, this is equal to or less than 1 / 4096 rotation as described above. In addition, the rotation angle within one rotation is also detected by the first rotation detection unit 310 with a resolution of 1 / 2 rotation or less, so that the rotation angle within one rotation is detected with redundancy.

[0024] Furthermore, the amount of multiple rotations T2 is not only detected by the first rotation detection unit 310, but is also obtained from the integrated amount of rotation angles within one rotation detected by the second rotation detection unit 320, so that the amount of multiple rotations is also detected with redundancy. In this manner, based on the comparison and synthesis CP of the amount of multiple rotations T1 and the rotation angle T2 within one rotation obtained by the redundant encoder 3100, rotation detection with redundancy is performed.

[0025] In the redundant encoder 3100 of the present invention, which aims to detect both the rotation angle within one rotation and the amount of multiple rotations with redundancy, the external power supply 329 is necessary to operate the second rotation detection unit 320. However, even if an abnormality occurs in the external power supply 329 and the second rotation detection unit 320 stops operating, the amount of multiple rotations can be detected up to a resolution of one rotation by the action of the first rotation detection unit 310, which has a resolution of 1 / 2 rotation or less.

[0026] Note that an optical, magnetic, electromagnetic induction, capacitive or other type of rotation detector can be used as the second rotation detector 320. For example, a magnetic resolver, an optical encoder, a capacitive encoder, etc.

[0027] 4 is an explanatory diagram showing the rotation detection action in the redundant encoder of the present invention. As shown in the figure, the redundant encoder 100 of the present invention performs the following rotation detection actions: detection of a rotation angle T1s within one rotation, which has a resolution of 1 / 2 rotation or less from the amount of rotation T1 obtained by the first rotation detection unit 10, detection of a multiple rotation amount T1m by integrating the amount of rotation T1, detection of a rotation angle T2s within one rotation, which has a higher resolution than that of the first rotation detection unit, for example a resolution of 1 / 4096 rotation or less, from the rotation angle T2 obtained by the second rotation detection unit 20, and detection of a multiple rotation amount T2m by integrating the rotation angle T2.

[0028] The multi-rotation amount T1m derived from the first rotation detection unit 10 and the rotation angle within one rotation T2s derived from the second rotation detection unit 20 are combined to obtain a rotation amount U with improved reliability as the rotation angle within one rotation and the multi-rotation amount.

[0029] As shown in the figure, the rotation angle within one rotation is detected with redundancy that matches with a resolution of 1 / 2 rotation or less by comparing rotation angle T1s and rotation angle T2s with CPs, while the multi-rotation amount T1m and the multi-rotation amount T2m are detected with redundancy that matches with the resolution of one rotation.

[0030] FIG. 5 is a second explanatory diagram showing the rotation detection function in the redundant encoder of the present invention. The lower part of the figure shows the angle positions that can be compared by stretching the angle positions within one rotation into a strip shape for each of the first rotation detection unit 510 (obtaining the amount of rotation T1) and the second rotation detection unit 520 (obtaining the rotation angle T2) constituting the redundant encoder 5100 shown in the upper part of the figure. Note that the magnetic field generating unit 55 constituting the first rotation detection unit 510 has two or more poles each of the N poles 52 and the S poles 53, but here an example is shown in which there are two poles each, for a total of four poles. That is, the detection resolution of the rotation angle within one rotation in the first rotation detection unit 510 is 1 / 2 rotation. On the other hand, the detection resolution of the rotation angle within one rotation in the second rotation detection unit 520 is 1 / 4096 rotation.

[0031] In one rotation, that is, in the range of 0° to 360°, 0° is detected as 0 / 2 rotation by first rotation detection unit 510 and 0 / 4096 rotation by second rotation detection unit 520, that is, as 0 rotation by both rotation detection units. Similarly, 360° is detected as 2 / 2 rotation by first rotation detection unit 510 and 4096 / 4096 rotation by second rotation detection unit 520, that is, as one rotation by both rotation detection units.

[0032] In addition, in the redundant encoder 5100 of the present invention, 180° is detected as 1 / 2 rotation by the first rotation detector 510 and as 2048 / 4096 rotation by the second rotation detector 520, that is, detected as 1 / 2 rotation or less by both rotation detectors. That is, redundant detection is performed up to 1 / 2 rotation, which is the resolution of the first rotation detector 510 (T1).

[0033] The redundant encoder of the present invention can be configured to include a comparison means for comparing rotation angle T1s with rotation angle T2s. By comparing rotation angle T1s with rotation angle T2s by the comparison means, the rotation angle within one rotation can be detected with the resolution of rotation angle T2 (for example, 1 / 4096 rotation or less), and can be detected with redundancy up to 1 / 2 rotation, which is the resolution of the amount of rotation T1.

[0034] The redundant encoder of the present invention can also be configured to include a comparison means for comparing the multi-rotation amount T1m with the multi-rotation amount T2m. By comparing the multi-rotation amount T1m with the multi-rotation amount T2m by the comparison means, the multi-rotation amount can be detected with redundancy that matches up to the resolution of one rotation. EXAMPLES

[0035] 6 is an explanatory diagram showing the configuration of an embodiment of a redundant encoder of the present invention. As shown in the figure, the magnetic field generating unit 65 of the first rotation detection unit 610 of this redundant encoder 6100 is composed of two N poles 62 and two S poles 63, for a total of four poles. In addition, a resolver is used as the second rotation detection unit 620. [Industrial Applicability]

[0036] According to the redundant encoder of the present invention, it is possible to detect both the rotation angle within one rotation and the amount of multiple rotations with redundancy, thereby improving the reliability of detection. Therefore, this invention has high industrial applicability in the fields of encoder manufacturing and use and all related fields. [Explanation of symbols]

[0037] 2, 22, 32, 62...N pole 3, 23, 33, 63…S pole 5, 25, 35, 65...Magnetic field generating section 10, 210, 310, 510, 610...First rotation detector 20, 220, 320, 520, 620...Second rotation detector 26, 36, 66...Magnetic generating element 27, 37, 67...Magnetic detection element 100, 2100, 3100, 5100, 6100...Redundant Encoders 318, 618...First signal processing circuit 328, 628...Second signal processing circuit 329…External power supply CP…Comparison / Synthesis CPm: Comparison of multi-turn amount T1m and multi-turn amount T2m CPs: Comparison of rotation angle T1s and rotation angle T2s T1: Amount of rotation (amount of multiple rotations) obtained by the first rotation detection unit T1m…Multiple rotations T1s…Rotation angle within one rotation T2: Rotation angle obtained by the second rotation detector T2m…Multiple rotations T2s: Rotation angle within one rotation U…Reliable rotation amount 700…Encoder (conventional technology) 720…Rotation detector 728…Signal processing circuit 729...External power supply 800…Encoder (conventional technology) 810...First rotation detector 85...Magnetic field generating section 86...Magnetic power generating element 87...Magnetic detection element 818...First signal processing circuit 820...Second rotation detector 828...Second signal processing circuit 829...External power supply

Claims

1. a first rotation detection unit that includes a magnetic field generating unit having two or more north poles and two or more south poles and detects the amount of rotation with a resolution of 1 / 2 rotation or less; and a second rotation detection unit that detects a rotation angle with a higher resolution than the first rotation detection unit, This provides a redundant encoder having redundancy in both the rotation angle within one rotation and the amount of multiple rotations.

2. 2. The redundant encoder according to claim 1, wherein the first rotation detection unit comprises a magnetic generating element having a large Barkhausen effect, and a magnetic detecting element having a Hall effect or a magnetoresistance effect.

3. 3. The redundant encoder according to claim 2, further comprising a first signal processing circuit for processing an output signal from the first rotation detection unit, and a second signal processing circuit for processing an output signal from the second rotation detection unit.

4. 4. The redundant encoder according to claim 3, wherein the second rotation detector and the second signal processing circuit are provided with an external power supply.

5. 5. The redundant encoder according to claim 1, wherein the second rotation detection unit is a rotation detector of an optical type, a magnetic type, an electromagnetic induction type, a capacitance type, or another type.

6. 5. The redundant encoder according to claim 1, wherein the resolution of the second rotation detection unit is 1 / 4096 rotation or less.

7. A rotation angle T1s within one rotation with a resolution of ½ rotation or less is detected from the rotation amount T1 obtained by the first rotation detection unit, The amount of rotation T1 is integrated to detect the amount of multiple rotations T1m. A rotation angle T2s within one rotation having a higher resolution than that obtained by the first rotation detection unit is detected from the rotation angle T2 obtained by the second rotation detection unit, The rotation angle T2 is integrated to detect the amount of multiple rotations T2m.

5. A redundancy encoder according to claim 1, 2, 3 or 4.

8. By comparing the rotation angle T1s with the rotation angle T2s, Detecting the rotation angle within one rotation with redundancy that matches with a resolution of 1 / 2 rotation or less; By comparing the amount of multiple rotations T1m and the amount of multiple rotations T2m, Detects multiple rotations with redundancy that matches the resolution of one rotation 8. A redundancy encoder as claimed in claim 7.

9. A signal processing apparatus comprising: a first signal processing circuit for processing an output signal from the first rotation detection unit; and a second signal processing circuit for processing an output signal from the second rotation detection unit, the second rotation detector and the second signal processing circuit are provided with an external power supply; The resolution of the second rotation detection unit is 1 / 4096 rotation or less, By comparing the rotation angle T1s with the rotation angle T2s, The rotation angle within one rotation is detected to 1 / 4096 rotation or less, which is the resolution of the rotation angle T2, and is also detected with redundancy to 1 / 2 rotation or less, which is the resolution of the rotation amount T1, By comparing the amount of multiple rotations T1m and the amount of multiple rotations T2m, Detects multiple rotations with redundancy that matches the resolution of one rotation 8. A redundancy encoder as claimed in claim 7.

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