Encoder with high permeability structure

Abstract

[Problem] To enhance vibration resistance and impact resistance in an encoder equipped with a magnetic power generation element having a large Barkhausen effect.　[Solution] An encoder 10 with a high permeability structure comprises a rotating disk 2, a magnetic field generation part 3, a magnetic power generation element 4 having a large Barkhausen effect, and a magnetic detection element 5. One or a plurality of high permeability structures, viz. high permeability structures 6, are provided so that the relative positions thereof with respect to the magnetic power generation element 4 are changeable. The magnetic field generation part 3 is disposed independently of the disk 2.

Description

Encoder with a high magnetic permeability structure

[0001] The present invention relates to an encoder with a high magnetic permeability structure, and particularly to a technique capable of enhancing the vibration resistance and shock resistance of an encoder equipped with a magnetic power generation element having a large Barkhausen effect.

[0002] Fig. 11 is an explanatory side sectional view showing the basic configuration of a conventional encoder equipped with a magnetic power generation element. Fig. 12 is an explanatory plan view and partially perspective view showing the basic operation of the encoder with a high magnetic permeability structure of the present invention shown in Fig. 11. An encoder 910 equipped with a magnetic power generation element having a conventional large Barkhausen effect, including the above-mentioned disclosed technology, is composed of a rotating disk 92, a magnetic field generation unit 93 such as a magnet, a magnetic power generation element 94 having a large Barkhausen effect, and a magnetic detection element 95. By rotating the magnetic field generation unit 93 to approach and separate from the magnetic power generation element 94, the magnetic flux density in the vicinity of the magnetic power generation element 94 is changed, thereby generating electricity. Examples of such prior art include Patent Documents 1 and 2 listed below.

[0003] Japanese Patent Application Laid-Open No. 2021-012174, "Rotation Detector and Motor Equipped Therewith"; Japanese Patent No. 7393577, "Rotary Encoder and Servo Control Device Using the Same"; Japanese Patent Application Laid-Open No. 2022-116385, "Rotation Detector and Motor Equipped Therewith"

[0004] In conventional encoders equipped with a magnetic power generation element, including the above-mentioned disclosed technology, a magnet is mainly used as the magnetic field generation unit. However, magnets have low toughness and are vulnerable to vibration, shock, etc. Therefore, surface treatment for protection may be performed on the magnet surface. There is a need for a technique that can enhance vibration resistance and shock resistance without using surface treatment.

[0005] Therefore, the problem to be solved by the present invention is to eliminate the problems of such prior art and provide a technique that can enhance vibration resistance and shock resistance without using surface treatment in an encoder equipped with a magnetic power generation element having a large Barkhausen effect.

[0006] As a result of considering the above problems, the inventors of this application found that the problems could be solved by fixing a magnetic field generating part, such as a magnet, near the magnetic power generation element, and by creating a structure that allows a highly permeable structure, such as iron, to be brought closer to and further away from the magnetic field generating part and the magnetic power generation element. Based on this, the present invention was completed. That is, the invention claimed in this application, or at least disclosed, as a means of solving the above problems is as follows.

[0007] [1] An encoder comprising a rotating disk, a magnetic field generating unit, a magnetic power generation element having a large Barkhausen effect, and a magnetic detection element, wherein one or more high-permeability structures, i.e., high-permeability structures, are provided so as to be able to change their relative position to the magnetic power generation element, and the magnetic field generating unit is arranged independently of the disk, characterized in that. [2] The encoder with a high-permeability structure according to [1], characterized in that the high-permeability structure rotates in conjunction with the disk. [3] The encoder with a high-permeability structure according to [2], characterized in that the high-permeability structure rotates around the magnetic power generation element. [4] The encoder with a high-permeability structure according to any one of [1], [2], or [3], characterized in that the high-permeability structure is formed and arranged in such a way that it can form a magnetic path between itself and the magnetic field generating unit and between itself and the magnetic power generation element.

[0008] [5] The encoder with a high permeability structure according to any one of [1], [2], or [3], characterized in that the magnetic field generating unit is fixed to a substrate which is one of the elements constituting the encoder. [6] The encoder with a high permeability structure according to any one of [1], [2], or [3], characterized in that the high permeability structure is formed of iron, nickel, cobalt, alloys thereof, and other ferromagnetic materials. [7] The encoder with a high permeability structure according to any one of [1], [2], or [3], characterized in that the rotation of the high permeability structure changes at least one of the magnetic flux density or the direction of the magnetic flux near the magnetic power generation element, thereby generating electricity from the magnetic power generation element. [8] The encoder with a high permeability structure according to any one of [1], [2], or [3], characterized in that the magnetic field generating unit is arranged to form a magnetic path with the magnetic power generation element.

[0009] [9] The encoder with a high permeability structure according to any one of [1], [2], or [3], characterized in that the magnetic field generating unit is arranged on the same substrate as the magnetic power generation element.

[10] The encoder with a high permeability structure according to any one of [1], [2], or [3], characterized in that the direction of its magnetic flux is aligned with the direction of the magnetic flux in the magnetic power generation element, and the magnetic field generating unit is arranged in two locations on either side of the magnetic power generation element.

[11] The encoder with a high permeability structure according to any one of [1], [2], or [3], characterized in that two of the high permeability structures are provided within a 180° range on the plane in which rotation occurs.

[0010] As described above, the encoder with a high-permeability structure of the present invention is configured in such a way that vibration resistance and shock resistance can be improved without using surface treatment. In other words, in the present invention, a high-permeability structure is positioned closer to and further away from the magnetic power generation element than a magnetic field generating part such as a magnet. Since a material with higher toughness than a magnet, such as iron, is used for this high-permeability structure, vibration resistance and shock resistance can be improved.

[0011] Furthermore, Patent Document 3, mentioned above, describes a technique for obtaining a large Barkhausen effect by fixing a magnet in place and rotating a high-permeability material together with a rotating axis. However, this technique uses a high-permeability disk for the purpose of shielding the magnetic field of the magnet. On the other hand, the present invention aims to guide the magnetic field of the magnet with a high-permeability structure, and therefore its patentability is not denied by the said prior art.

[0012] This is a side cross-sectional view illustrating the basic configuration of the encoder with a high-permeability structure of the present invention. This is a plan view and partially perspective diagram illustrating the main parts of the encoder with a high-permeability structure of the present invention shown in Figure 1, illustrating the basic operation of the encoder with a high-permeability structure of the present invention. This is a bottom view diagram illustrating the main parts of an example configuration of the encoder with a high-permeability structure of the present invention. This is a bottom view and partially perspective diagram illustrating the main parts of the encoder with a high-permeability structure shown in Figure 3, illustrating the operation of the encoder with a high-permeability structure shown in Figure 3. This is a bottom view and partially perspective diagram illustrating the magnetic flux change in the encoder with a high-permeability structure shown in Figure 4. This is a side cross-sectional view illustrating an embodiment of the encoder with a high-permeability structure of the present invention. This is a perspective view from below of the embodiment shown in Figure 5. This is a perspective view from above of the embodiment shown in Figure 5. This is a partially perspective bottom view of the main parts illustrating the relationship between the main elements of the embodiment shown in Figure 5. This is a perspective view illustrating the disk of the embodiment shown in Figure 5. This is a perspective view from below illustrating the relationship between the main elements of the embodiment shown in Figure 5. This is a side cross-sectional view illustrating the basic configuration of a conventional encoder equipped with a magnetic power generation element. This is a plan view and partially perspective diagram illustrating the basic operation of the encoder with a high-permeability structure of the present invention shown in Figure 11.

[0013] The present invention will be described in detail below with reference to the drawings. Figure 1 is an explanatory diagram of a side cross-sectional view showing the basic configuration of the present invention. Figure 2 is an explanatory diagram of the main parts in a plan view showing the basic operation of the encoder with a high permeability structure of the present invention shown in Figure 1. As shown here, the encoder with a high permeability structure 10 is an encoder comprising a rotating disk 2, a magnetic field generating unit 3, a magnetic power generation element 4 having a large Barkhausen effect, and a magnetic detection element 5, characterized in that one or more high permeability structures, i.e., high permeability structures 6, are provided so as to be able to change their relative position to the magnetic power generation element 4, and the magnetic field generating unit 3 is arranged independently of the disk 2.

[0014] In this encoder 10 with a high-permeability structure, the magnetic field generating unit 3 is positioned independently of the disk 2, so even if the disk 2 rotates, the magnetic field generating unit 3 does not rotate. On the other hand, as shown in Figures 2(a) and (b), the relative position of one or more high-permeability structures 6 with respect to the magnetic power generation element 4 changes. This change in the relative position of the high-permeability structure 6 causes a change in at least one of the magnetic flux density or the direction of the magnetic flux near the magnetic power generation element 4, thereby generating electricity. In this way, the function that was performed by the rotating magnetic field generating unit (93) in the conventional technology is ensured by the high-permeability structure 6. Note that this change in relative position occurs in conjunction with the rotation of the disk 2.

[0015] The encoder 10 with a high-permeability structure of the present invention has a structure in which the high-permeability structure 6 approaches and moves away from the magnetic power generation element 4, rather than the magnetic field generating part 3 such as a magnet. Since the high-permeability structure 6 is made of a material such as iron which has higher toughness than a magnet, vibration resistance and shock resistance can be improved compared to conventional technology.

[0016] The high-permeability structure 6 of this encoder 10 with a high-permeability structure can be configured to rotate in conjunction with the disk 2. As shown in Figure 1, by configuring the high-permeability structure 6 to be fixed to the disk 2, the rotation of the high-permeability structure 6 becomes the same as the rotation of the disk 2. That is, as shown in Figure 2, the high-permeability structure 6 rotates in accordance with the rotation of the disk 2, thereby changing its relative position to the magnetic power generation element 4 and causing a change in the magnetic flux density near the magnetic power generation element 4.

[0017] Furthermore, as shown in Figures 1 and 2, the high-permeability structure 6 can be configured to rotate around the magnetic power generation element 4. As a result, the high-permeability structure 6, which rotates in accordance with the rotation of the disk 2, changes its relative position with respect to the magnetic power generation element 4, which is its center of rotation, and thus causes a change in the magnetic flux density near the magnetic power generation element 4.

[0018] In order to perform the functions described above, the high-permeability structure 6 of the encoder 10 with this high-permeability structure can be configured and arranged in such a way that it can form magnetic paths with the magnetic field generating unit 3 and with the magnetic power generation element 4. Such "specifications that enable the formation of magnetic paths" may be structural features, morphological features, or material / characteristic features.

[0019] From the viewpoint of forming a magnetic path with sufficient magnetic force, it is desirable to have multiple high-permeability structures 6 in this encoder 10 with a high-permeability structure, and by providing two as shown in each figure, the full effect intended by the present invention can be obtained. However, it is not desirable to provide three high-permeability structures 6. If three are provided, the magnetic force will be reduced by the high-permeability structure located in the center, which may cause the magnetic power generation element (Wiegant sensor) 4 to malfunction. Therefore, the optimal number of high-permeability structures 6 is two.

[0020] Furthermore, in situations where a magnetic path can be formed, in order to bring about a change in magnetic flux density near the magnetic power generation element 4, the high-permeability structure 6 is arranged so as to ensure the directionality of the formed magnetic path. Therefore, the arrangement of multiple high-permeability structures 6 that are point-symmetric or line-symmetric with respect to the magnetic power generation element 4 is undesirable. For example, if two magnetic power generation elements 4 are arranged at a certain angle, it is undesirable to have two more magnetic power generation elements 4 arranged point-symmetrically with respect to these two elements. This is because it becomes difficult to ensure the directionality of the formed magnetic path.

[0021] Suitable materials for the high-permeability structure 6 include iron, nickel, cobalt, their alloys, and other ferromagnetic materials. This is because these materials have high permeability and higher toughness and rigidity than magnets. For example, carbon steel for mechanical structures such as S45C is suitable as a material for the high-permeability structure 6 according to the present invention. Incidentally, the rigidity modulus of S45C is 206 GPa, while the rigidity modulus of neodymium, which is used in permanent magnets, is 16.3 Ga. In other words, S45C has more than 10 times the rigidity of neodymium.

[0022] The magnetic field generating unit 3 of this high-permeability structure encoder 10 is characterized by being arranged to form a magnetic path with the magnetic power generation element 4. As shown in Figure 1, the magnetic field generating unit 3 can be fixed to the substrate 1 of the encoder 10. As shown in the figure, the magnetic field generating unit 3 is fixedly arranged near the magnetic power generation element 4, and by configuring the high-permeability structure 6 to be brought closer to and further away from the magnetic field generating unit 3 and the magnetic power generation element 4, the intended effects of the present invention can be fully obtained. In addition to a permanent magnet using neodymium or the like, an electromagnet may be used as the magnetic field generating unit 3.

[0023] Figure 3 is a plan view diagram illustrating the main components of an example configuration of the encoder with a high-permeability structure of the present invention. As shown in the figure, in addition to the configurations of the patterns described in Figure 1 and the like, the encoder with a high-permeability structure 310 can be configured such that the magnetic field generating unit 33 is arranged on the same substrate 31 as the magnetic power generation element 34. The magnetic field generating unit 33a and the like of the encoder 310 of the present invention are arranged independently of the disk 32, but as shown in this figure, they are fixedly mounted on the substrate 31, so they do not rotate even when the disk 32 rotates.

[0024] Furthermore, as shown in the figure, the magnetic field generating unit can be configured such that the direction of its magnetic flux is aligned with the direction of the magnetic flux in the magnetic power generation element 34, and is positioned in two locations on either side of the magnetic power generation element 34, i.e., magnetic field generating units 33a and 33b are provided. The arrangement relationship between the two magnetic field generating units 33a and 33b and the magnetic power generation element 34 remains constant on the substrate 31. Each magnetic field generating unit 33a, etc. consists of a north pole in the dark area indicated as "N" and a south pole in the light area indicated as "S" in the figure (the same applies to the following figures).

[0025] Furthermore, as shown in the figure, the encoder 310 with a high permeability structure can be configured such that two high permeability structures, i.e., high permeability structures 36a and 36b, are provided within a 180° range on the plane where rotation occurs. With this configuration, the magnetic path between the high permeability structure 36, the magnetic field generating unit 33, and the magnetic power generation element 34 is formed well, and the relative position change of the high permeability structure 36 with respect to the magnetic power generation element 34 due to the rotation of the disk 32 is brought about well, and a smooth change in at least one of the magnetic flux density or the direction of the magnetic flux near the magnetic power generation element 34 can be obtained.

[0026] Figure 4 is a plan view and partially transparent diagram illustrating the operation of the encoder with a high-permeability structure shown in Figure 3. Figure 4-2 is a bottom view and partially transparent diagram illustrating the change in magnetic flux in the encoder with a high-permeability structure shown in Figure 4. In these figures, (i), (ii), (iii), and (iv) show the magnetic flux generation situation at 90° intervals when the disk 32 rotates in the disk rotation direction D. First, at 0° (i), the magnetic flux MS1 enters from the magnetic power generation element (Wiegant sensor) 34 through the high-permeability structure 36a to the S pole of the magnetic field generation unit 33a, and this exits from the N pole of the magnetic field generation unit 33a, passes through the high-permeability structure 36b, and enters the magnetic power generation element 34 again as magnetic flux MN1.

[0027] On the other hand, the magnetic flux MS2 entering the S pole of the magnetic field generating unit 33b and the magnetic flux MN2 exiting from the N pole are weaker than the magnetic fluxes MS1 and MN1 passing through the high-permeability structures 36a and 36b. In other words, the magnetic flux density is higher when passing through the high-permeability structures 36a and 36b (represented by the thickness of the arrows indicating magnetic flux in the figure; the same applies below). As a result, a magnetic flux ML is added to the magnetic power generation element 34, directed from the high-permeability structure 36b side to the high-permeability structure 36a side, as shown in the left-hand direction in the figure. This magnetic flux density and direction change as the disk 32 rotates, causing a change in magnetic flux near the magnetic power generation element 34.

[0028] Next, in state (ii), where the disk 32 has been rotated 90° from state (i), magnetic flux MS1 enters from the magnetic power generation element 34 through the high permeability structure 36b to the south pole of the magnetic field generating unit 33a, and this exits from the north pole of the magnetic field generating unit 33a as magnetic flux MN1 and enters the magnetic power generation element 34 again. Meanwhile, there is magnetic flux MS2 entering the south pole of the magnetic field generating unit 33b, and magnetic flux MN2 exiting from the north pole and entering the magnetic power generation element 34 again through the high permeability structure 36a.

[0029] Here, the magnetic fluxes MN1 and MS2 that do not pass through the high-permeability structure are weaker than the magnetic fluxes MS1 and MN2 that pass through the high-permeability structures 36b and 36a. In other words, the magnetic flux density of MS1 and MN2 that pass through the high-permeability structures 36b and 36a is higher. The magnetic flux MN2 is more likely to connect directly to the magnetic flux MS1 rather than passing through the magnetic power generation element 34. Therefore, the magnetic flux applied to the magnetic power generation element 34 is almost zero. In this way, when the disk 32 rotates 90° from (i) to (ii), a change in magnetic flux occurs in the magnetic flux density and direction of the magnetic flux near the magnetic power generation element 34.

[0030] Next, in state (iii), where disk 32 has rotated 90° from (ii) and 180° from (i), magnetic flux MS2 enters from the magnetic power generation element 34 through the high permeability structure 36a to the S pole of the magnetic field generation unit 33b. This then exits from the N pole of the magnetic field generation unit 33b, passes through the high permeability structure 36b, and enters the magnetic power generation element 34 again as magnetic flux MN2.

[0031] On the other hand, the magnetic flux MS1 entering the S pole of the magnetic field generating section 33a and the magnetic flux MN1 exiting from the N pole are weaker than the magnetic fluxes MS2 and MN2 passing through the high-permeability structures 36a and 36b. In other words, the magnetic flux density of MS2 and MN2 passing through the high-permeability structures 36a and 36b is higher. As a result, a magnetic flux MR is added to the magnetic power generation element 34, directed from the high-permeability structure 36b side to the high-permeability structure 36a side, as shown in the diagram on the right. Thus, when the disk 32 rotates 90° from (ii) to (iii), a change in magnetic flux occurs in the magnetic flux density and direction of the magnetic flux near the magnetic power generation element 34.

[0032] Next, in state (iv), where disk 32 has rotated 90° from (iii) and 270° from (i), magnetic flux MS2 enters from the magnetic power generation element 34 through the high permeability structure 36b to the S pole of the magnetic field generating unit 33b, and this exits from the N pole of the magnetic field generating unit 33b as magnetic flux MN2 and enters the magnetic power generation element 34 again. Meanwhile, there is magnetic flux MS1 entering the S pole of the magnetic field generating unit 33a, and magnetic flux MN1 exiting from the N pole and exiting through the high permeability structure 36b to enter the magnetic power generation element 34 again.

[0033] Here, the magnetic fluxes MN2 and MS1 that do not pass through the high-permeability structures are weaker than the magnetic fluxes MS2 and MN1 that pass through the high-permeability structures 36a and 36b. In other words, the magnetic flux density of MS2 and MN1 that pass through the high-permeability structures 36a and 36b is higher. The magnetic flux MN2 is more likely to connect directly to the magnetic flux MS1 rather than passing through the magnetic power generation element 34. Therefore, the magnetic flux applied to the magnetic power generation element 34 is almost zero. In this way, when the disk 32 rotates 90° from (iii) to (iv), a change in magnetic flux occurs in the magnetic flux density and direction of the magnetic flux near the magnetic power generation element 34.

[0034] As explained above, in this encoder 310 with a high-permeability structure, as the disk 32 rotates, the relative positions of the high-permeability structures 36a and 36b with respect to the magnetic power generation element 34 and the magnetic field generating units 33a and 33b change. This changes the magnetic flux density and direction of the magnetic flux near the magnetic power generation element 34, and consequently changes the magnitude and direction of the magnetic flux density within the magnetic power generation element 34. As a result, power is generated.

[0035] An embodiment of the encoder with a high-permeability structure of the present invention will be described, but the present invention is not limited thereto. Figure 5 is a side cross-sectional view showing an embodiment of the encoder with a high-permeability structure of the present invention. Figure 6 is a perspective view from below of the same embodiment, Figure 7 is a perspective view from above of the same embodiment, Figure 8 is a partial perspective view of the main parts showing the relationship between the main elements of the same embodiment, Figure 9 is a perspective view showing the disk of the same embodiment, and Figure 10 is a perspective view from below showing the relationship between the main elements of the same embodiment.

[0036] As shown in the figures, the encoder 510 with a high permeability structure in this example comprises a disk 52, a magnetic power generation element (Wiegand sensor) 54 having a large Barkhausen effect, magnetic field generating units 53a and 53b provided on either side of the magnetic power generation element 54, and a magnetic detection element (not shown). Two high permeability structures 56a and 56b are provided so as to be able to change their relative position to the magnetic power generation element 54, and the magnetic field generating units 53a and 53b are arranged independently of the disk 52. In other words, the magnetic field generating units 53a and 53b are provided on the substrate 51 together with the magnetic power generation element 54, which is a characteristic configuration.

[0037] With this configuration, in the encoder 510 with high permeability structures in this example, even if the disk 52 rotates, the magnetic field generating units 53a and 53b do not rotate. On the other hand, the relative positions of the two high permeability structures 56a and 56b with respect to the magnetic power generation element 54 change. This change in the relative positions of the high permeability structures 56a and 56b causes a change in at least one of the magnetic flux density or the direction of the magnetic flux near the magnetic power generation element 54, thereby generating electricity.

[0038] Furthermore, since the high-permeability structures 56a and 56b are provided on the disk 52, the relative position changes occur in conjunction with the rotation of the disk 52. In other words, this encoder 510 with a high-permeability structure is an encoder that has a mechanism for generating electricity by changing the magnetic flux density near the magnetic power generation element 54 by moving the high-permeability structures 56a and 56b closer to and further away from the magnetic field generating section 53a and 53b and the magnetic power generation element 54.

[0039] The encoder with a high-permeability structure of the present invention uses a material with higher toughness than conventional materials for the elements whose relative position changes with respect to the magnetic power generation element. Therefore, vibration resistance and shock resistance can be improved without the use of surface treatment. Consequently, this invention has high industrial applicability in the manufacturing and usage fields of encoders equipped with magnetic power generation elements, as well as in all related fields.

[0040] 1, 31, 51…Substrate 2, 32, 52…Disk 3, 33a, 33b, 53a, 53b…Magnetic field generator 4, 34, 54…Magnetic power generation element (Wiegand sensor) 5…Magnetic detection element 6, 36a, 36b, 56a, 56b…High permeability structure 10, 310, 510…Encoder with high permeability structure 58…Base D…Disk rotation direction ML, MR…Magnetic flux applied to magnetic power generation element (Wiegand sensor) MN1, MN2…Magnetic flux emanating from the N pole MS1, MS2…Magnetic flux entering the S pole N…N pole (of magnetic field generator 36a, 36b) S…S pole (of magnetic field generator 36a, 36b) 91…Substrate 92…Disk 93…Magnetic field generator 94…Magnetic power generation element 95…Magnetic detection element 910…Conventional encoder

Claims

1. An encoder comprising a rotating disk, a magnetic field generating unit, a magnetic power generation element having a large Barkhausen effect, and a magnetic detection element, wherein one or more high-permeability structures, i.e., high-permeability structures, are provided so as to be able to change their relative position to the magnetic power generation element, and the magnetic field generating unit is arranged independently of the disk, characterized in that an encoder with high-permeability structures.

2. The encoder with a high permeability structure according to claim 1, characterized in that the high permeability structure rotates in conjunction with the disk.

3. The encoder with a high permeability structure according to claim 2, characterized in that the high permeability structure rotates around the magnetic power generation element.

4. The encoder with a high permeability structure according to any one of claims 1, 2, or 3, characterized in that the high permeability structure is formed and arranged in such a way that it can form a magnetic path between itself and the magnetic field generating unit and between itself and the magnetic power generation element.

5. The encoder with a high magnetic permeability structure according to any one of claims 1, 2, or 3, characterized in that the magnetic field generating unit is fixed to a substrate which is one of the elements constituting the encoder.

6. The encoder with a high permeability structure according to any one of claims 1, 2, or 3, characterized in that the high permeability structure is formed of iron, nickel, cobalt, alloys thereof, and other ferromagnetic materials.

7. An encoder with a high-permeability structure according to any one of claims 1, 2, or 3, characterized in that the high-permeability structure rotates to change at least one of the magnetic flux density or the direction of the magnetic flux near the magnetic power generation element, thereby generating electricity from the magnetic power generation element.

8. The encoder with a high permeability structure according to any one of claims 1, 2, or 3, characterized in that the magnetic field generating unit is arranged to form a magnetic path with the magnetic power generation element.

9. The encoder with a high permeability structure according to any one of claims 1, 2, or 3, characterized in that the magnetic field generating unit is arranged on the same substrate as the magnetic power generation element.

10. The encoder with a high permeability structure according to any one of claims 1, 2, or 3, characterized in that the magnetic field generating unit is positioned so that the direction of its magnetic flux matches the direction of the magnetic flux in the magnetic power generation element, and is positioned in two locations on either side of the magnetic power generation element.

11. The encoder with a high permeability structure according to any one of claims 1, 2, or 3, characterized in that two of the high permeability structures are provided within a 180° range on the plane in which rotation occurs.

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