Rotary encoder

Abstract

Provided is a rotary encoder capable of reducing manufacturing costs. A rotary encoder (10) is provided with a magnetic detection element (2) and a magnetic field generating portion (3) provided with a magnetic yoke (4). By providing the magnetic yoke (4) to the magnetic field generating portion (3), the magnetic flux density can be increased. In addition, as the magnetic field generating portion (3), a permanent magnet can be used. In addition, as the magnetic yoke (4), a magnetic body plate-shaped body provided at the end portion of the magnetic field generating portion (3) on the side away from the magnetic power generation element can be used.

Description

Technical Field

[0001] This invention relates to rotary encoders, and more particularly to rotary encoders that can reduce manufacturing costs. Background Technology

[0002] In conventional rotary encoders equipped with magnetoelectric elements exhibiting a large Barkhausen effect, magnetic field generating units such as magnets are used. Patent applications have been filed for rotary encoders equipped with magnetoelectric elements exhibiting a large Barkhausen effect.

[0003] For example, in Patent Document 1 described later, a method for manufacturing a power generation element, encoder, and magnetic component capable of increasing power generation is disclosed. The method comprises a power generation element consisting of a magnetic component that generates a large Barkhausen effect, a coil wound around it, and a ferrite component disposed at the end of the magnetic component. It also discloses a structure consisting of a body portion located inside a cylindrical space and a protrusion located outside the cylindrical space. Furthermore, the cylindrical space is assumed to be surrounded by an imaginary surface extending the outer edge of the coil to both sides in the winding axis direction, and is formed to be clamped by two imaginary surfaces that respectively contact both ends of the magnetic component and are orthogonal to the winding axis direction.

[0004] Prior art literature

[0005] Patent documents

[0006] Patent Document 1: WO2022 / 230651 Publication No. "Manufacturing Method of Power Generation Element, Encoder and Magnetic Component" Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] For magnetic power generation components exhibiting a large Barkhausen effect, a certain magnetic flux density is required to generate electricity. Therefore, depending on the product's structure and the environment in which it is used, magnets with high magnetic flux density are needed, which becomes a major reason for the high product cost.

[0009] Therefore, the problem to be solved by the present invention is to provide a rotary encoder that can reduce manufacturing costs, based on the problems of the prior art.

[0010] Solution for solving the problem

[0011] The applicant of this invention conducted research on the aforementioned problems and discovered that, in a rotary encoder equipped with a magnetoelectric element exhibiting a large Barkhausen effect, the aforementioned problems can be solved by having a plate-shaped structure made of a magnetic material such as iron contact the side away from the magnetoelectric element relative to the magnetic field generating part such as a magnet, thus acting as a yoke. Furthermore, based on this, the present invention was completed through further research. That is, as a solution to the aforementioned problems, the invention claimed in this application, or at least the invention disclosed herein, is as follows.

[0012] [1] A rotary encoder, the rotary encoder having a magnetic detection element and a magnetic field generating part, characterized in that a magnetic yoke is provided in the magnetic field generating part.

[0013] [2] A rotary encoder comprising a magnetic field generating section, a magnetic power generation element having a large Barkhausen effect and a magnetic detection element having a Hall effect or a magnetoresistive effect, characterized in that a magnetic yoke is provided in the magnetic field generating section.

[0014] [3] The rotary encoder according to any one of [1] and [2] is characterized in that the magnetic field generating part is composed of two or more magnetic field generating part units that are magnetized along the axial direction joined in the radial direction, and the adjacent magnetic field generating part units are arranged with different magnetic poles.

[0015] [4] The rotary encoder according to any one of [1] and [2] is characterized in that the magnetic yoke is a magnetic plate-shaped body.

[0016] [5] The rotary encoder according to any one of [1] and [2] is characterized in that the magnetic yoke is disposed at the end of the magnetic field generating part on the side away from the magnetic power generation element.

[0017] The effects of the invention

[0018] Because the rotary encoder of the present invention is configured as described above, the magnetic flux density can be increased compared to the prior art structure without a magnetic yoke. Therefore, relatively inexpensive magnets with low magnetic flux density can be used, thus reducing costs. Furthermore, the technology disclosed in Document 1 relates to encoder structures using Wiegand sensors and is unrelated to the present invention. Attached Figure Description

[0019] Figure 1 This is a cross-sectional view illustrating the basic structure of the rotary encoder of the present invention.

[0020] Figure 2 This is a cross-sectional view illustrating the function of the rotary encoder of the present invention.

[0021] Figure 3This is a cross-sectional view illustrating the basic structure of the rotary encoder of the present invention, which is conceptually represented by a magnetoelectric element.

[0022] Figure 4 This is a perspective illustration showing the basic structure of the magnetic field generating part of the rotary encoder of the present invention.

[0023] Figure 5 This is a cross-sectional view illustrating the main parts of an embodiment of the rotary encoder of the present invention. Detailed Implementation

[0024] The present invention will now be described in detail with reference to the accompanying drawings.

[0025] Figure 1 This is a cross-sectional view illustrating the basic structure of the rotary encoder of the present invention. As shown, the rotary encoder 10 is a rotary encoder comprising a magnetic detection element 2 and a magnetic field generating unit 3, and its main structure is characterized by a magnetic yoke 4 provided in the magnetic field generating unit 3. In this rotary encoder 10 with this structure, the magnetic flux density can be increased by providing a magnetic yoke 4 in the magnetic field generating unit 3. Further explanation will be provided using other figures.

[0026] Figure 2 This is a cross-sectional diagram illustrating the function of the rotary encoder of the present invention. Figure (a) shows the main part of the present invention, and (b) shows the main part of the prior art. In the prior art, magnetic fluxes F91 and F92 of equal magnitude and flux density are generated by the magnetic field generating unit 93 (Figure (b)). On the other hand, in the present invention, where the flux density is increased by the yoke 24, the flux generated by the magnetic field generating unit 23 is greater in the flux F1 on the side opposite to the side where the yoke 24 is located than in the flux F2 on the side where the yoke 24 is located. Thus, in the present invention, the effect of increasing the flux density can be achieved by using the yoke 24.

[0027] Figure 3 This is a cross-sectional view illustrating the basic structure of the rotary encoder of the present invention, which conceptually incorporates a magnetoelectric element. As shown, the rotary encoder 310 is, in addition to... Figure 1 The structure described herein includes, in addition to the magnetic detection element 32, the magnetic field generating unit 33, and the magnetic yoke 34 disposed on the magnetic field generating unit 33, a magnetic power generation element 35 having a large Barkhausen effect. That is, the rotary encoder with this structure is also within the scope of this invention.

[0028] In this rotary encoder 310 with this structure, the magnetic flux density can be increased by providing a magnetic yoke 34 in the magnetic field generating section 33. Its function is as described above. Figure 2 As explained. In addition, the magnetic detection element 32 can be a structure with Hall effect or magnetoresistive effect.

[0029] like Figure 3As shown, the yoke 34 of the rotary encoder 310 of the present invention can be configured as an end of the magnetic field generating section 33 located on the side away from the magnetoelectric element 35. Furthermore, the magnetic field generating section 33 uses a magnet or the like, and the yoke 34 can preferably be a plate-shaped structure made of a magnetic material such as iron. By contacting the side of the magnetic field generating section 33 away from the magnetoelectric element 35, the plate-shaped structure functions as the yoke 34.

[0030] As the magnetic yoke 34, a plate-like structure such as a washer can be used, for example. Depending on the thickness of the plate-like structure such as the washer or the number of overlapping arrangements, the magnetic flux density can be designed to a desired or appropriate size.

[0031] Figure 4 This is a perspective illustration showing the basic structure of the magnetic field generating unit of the rotary encoder of the present invention. As shown, the magnetic field generating unit 43 is composed of two or more axially magnetized magnetic field generating unit units 49 joined radially, with adjacent magnetic field generating unit units 49 arranged in a manner that distinguishes their magnetic poles. That is, in the magnetic field generating unit 49 located at the front of the figure, its upper part is the N pole 46, and in the adjacent magnetic field generating unit unit 49 located at the rear of the figure, its upper part is the S pole 47. On the other hand, in the lower part of each magnetic field generating unit unit 49, the magnetic poles are arranged in opposite directions. In addition, the figure shows the magnetic fluxes F1d, F1x, F2d, and F2x generated by the magnetic field generating unit 43 in the axial direction.

[0032] Figure 5 This is a cross-sectional view illustrating the main parts of an embodiment of the rotary encoder of the present invention. As shown, the rotary encoder 510 of this embodiment includes: a magnetoelectric element 55 having a large Barkhausen effect; a magnetic detection element 52 having a Hall effect or magnetoresistive effect; and a magnetic field generating section 53. At the end of the magnetic field generating section 53 on the side away from the magnetoelectric element 55, a magnetic yoke 54 is provided on a magnetic plate-like body. Therefore, compared with the prior art structure, the magnetic flux density can be increased.

[0033] Industrial availability

[0034] The rotary encoder according to the present invention can increase magnetic flux density compared with prior art structures without a magnetic yoke, thus enabling the use of relatively inexpensive magnets with low magnetic flux density, which helps to reduce costs. Therefore, it is an invention with high industrial applicability in the fields of encoder manufacturing, application, and all related fields.

[0035] Explanation of reference numerals in the attached figures

[0036] 1, 31, 51… code disk

[0037] 2, 32, 52… magnetic detection elements

[0038] 3, 23, 33, 43, 53… Magnetic field generating section

[0039] 4, 24, 34, 54… magnetic yoke

[0040] 8, 28, 38, 58… axis

[0041] 10, 310, 510… Rotary encoders

[0042] 35, 55… Magnetic power generation components

[0043] 46…N pole

[0044] 47…S pole

[0045] 49…Magnetic Field Generating Unit

[0046] 50...Substrate

[0047] F1, F1d, F1x, F2, F2d, F2x… magnetic flux

[0048] 93…Magnetic Field Generation Section

[0049] 98… axis

[0050] F91, F92... magnetic flux

Claims

1. A rotary encoder, the rotary encoder comprising a magnetic detection element and a magnetic field generating unit, characterized in that, A magnetic yoke is provided in the magnetic field generating part.

2. A rotary encoder, the rotary encoder comprising a magnetic field generating unit, a magnetoelectric element having a large Barkhausen effect, and a magnetic detection element having a Hall effect or magnetoresistive effect, characterized in that, A magnetic yoke is provided in the magnetic field generating part.

3. The rotary encoder according to any one of claims 1 and 2, characterized in that, The magnetic field generating section is formed by joining two or more magnetic field generating section units that are magnetized along the axial direction in the radial direction, and the adjacent magnetic field generating section units are arranged with different magnetic poles.

4. The rotary encoder according to any one of claims 1 and 2, characterized in that, The magnetic yoke is a magnetic plate-shaped body.

5. The rotary encoder according to any one of claims 1 and 2, characterized in that, The magnetic yoke is located at the end of the magnetic field generating part on the side away from the magnetic power generation element.

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