JP2008122334A - Rotation detector and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotation detector capable of improving the detection sensitivity, and to provide a manufacturing method for the rotation detector. <P>SOLUTION: The rotation detector 100 for detecting the rotating state of a rotor 200 comprises a cylindrical magnet 40 that generates a bias magnetic field, with its edge facing at least a rotating body 200 being open; a magnetic detection element 10, in a bare chip state that outputs detection signal according to the change in the bias magnetic field that accompanies the rotation of the rotating body 200; a mount section 21 for holding the magnetic detecting element 10 inside the cylindrical magnet 40; and a sealing material 50, filled inside the cylindrical magnet 40, where the magnetic detecting element 10 is held by the mounting section 21. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rotation detection device and a method for manufacturing the rotation detection device. In particular, the present invention relates to a rotation detection device that is disposed in the vicinity of a rotating body (detected body) and detects a rotation state of the rotating body based on a change in a bias magnetic field, and a method of manufacturing the rotation detecting device.

  Conventionally, there has been a rotation detection apparatus disclosed in Patent Document 1 that is arranged in the vicinity of a rotating body (detected body) and detects a rotating state of the rotating body based on a change in a bias magnetic field.

The rotation detection device shown in Patent Document 1 includes a cylindrical magnet that generates a bias magnetic field, a magnetic detection element mounted in a holding chip in a state of a bare chip, one end opened, and the other end closed. A cylindrical housing. This magnetic detection element is disposed in a cylindrical magnet, and is inserted from one end (opening) of the housing together with the cylindrical magnet, and the other end (closed). Located in the vicinity.
JP 2006-275639 A

  However, the rotation detection device shown in Patent Document 1 has a housing (closed end) between the magnetic detection element and the detection target, so that the distance between the magnetic detection element and the detection target is increased, and detection accuracy is increased. May be reduced. It is also conceivable to remove the housing in order to reduce the distance between the magnetic detection element and the detection target. However, the magnetic detection element of the rotation detection device shown in Patent Document 1 is in a bare chip state, and may be adversely affected by the external environment when the housing is removed.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a rotation detection device and a rotation detection device manufacturing method that can suppress adverse effects from the external environment and improve detection accuracy. To do.

  In order to achieve the above object, a rotation detection device according to claim 1 is a rotation detection device for detecting a rotation state of a detection object, which generates a bias magnetic field and faces at least the detection object. A cylindrical magnet having an open end, a magnetic detection element that outputs a detection signal according to a change in a bias magnetic field accompanying rotation of the detection object, and a holding member that holds the magnetic detection element in the cylindrical magnet And a sealing material filled in a cylindrical magnet in which the magnetic detection element is held by the holding member.

  As described above, by providing the sealing material in the cylindrical magnet in which the magnetic detection element held by the holding member is arranged, the magnetic detection element can be placed in the external environment without providing a housing that covers the opening of the magnet. Can be protected from. Therefore, the distance between the magnetic detection element and the detected object can be reduced by the amount that there is no housing or the like covering the opening of the magnet, and the detection accuracy can be improved.

  Moreover, you may make it provide the base member to which the site | part different from the edge part which opposes the to-be-detected body of a cylindrical magnet as shown in Claim 2. By doing in this way, it can suppress that a sealing material leaks from between a base member and a magnet.

  According to a third aspect of the present invention, the pedestal member may be provided with a press-fitting portion at a site where the cylindrical magnet is connected, and the cylindrical magnet may be press-fitted into the press-fitting portion. By doing in this way, it becomes easy to contact | adhere a base member and a cylindrical magnet, Furthermore, it can suppress that a sealing material leaks from between a base member and a magnet.

  Moreover, as shown in Claim 4, it can suppress that a sealing material leaks from between a base member and a magnet also by connecting a base member and a cylindrical magnet via an adhesive material.

  Moreover, as shown in claim 5, the holding member may be connected to the base member.

  According to a sixth aspect of the present invention, the pedestal member may include a cylindrical magnet positioning mechanism.

  By doing in this way, a base member and a magnet are positioned and a magnetic detection element and a magnet can be positioned.

  According to a seventh aspect of the present invention, the pedestal member may have a groove on the surface, and the groove may be filled with a sealing material.

  By doing in this way, the anchor effect of a sealing material can improve and adhesive force can be improved.

  In addition, as shown in claim 8, the holding member and the magnetic detection element may be arranged inside the end face of the cylindrical magnet.

  By doing in this way, a cylindrical magnet acts as a cover of a holding member and a magnetic detection element, and can protect a holding member and a magnetic detection element.

  Moreover, as a sealing material, as shown in Claim 9, it can be set as a thermosetting resin.

  Since the thermosetting resin is relatively hard, as shown in claim 9, by using the thermosetting resin as the sealing material, the influence from the outside can be suppressed and the magnetic detection element can be protected.

  Moreover, as a sealing material, as shown in Claim 10, you may use a gel-like member.

  Since the gel-like member is relatively soft and can relieve stress, stress concentration due to the difference in thermal expansion coefficient of each component can be suppressed.

  In addition, as shown in claim 11, the pedestal member may include a claw portion for connecting to a cylindrical magnet, and the cylindrical magnet may include a concave portion corresponding to the claw portion.

  By doing in this way, a base member and a magnet can be firmly fixed with a claw part of a base member, and a crevice of a magnet.

  According to a twelfth aspect of the present invention, at least one of the claw portion of the pedestal member and the pedestal side end portion of the cylindrical magnet may have a tapered shape.

  By doing in this way, it can make it easy to insert the nail | claw part of a base member in the recessed part of a magnet.

  According to a thirteenth aspect of the present invention, there is provided a rotation detection device manufacturing method for detecting a rotation state of a detected object, which generates a bias magnetic field, and at least faces the detected object. An arrangement step of arranging a magnetic detection element that outputs a detection signal in accordance with a change in a bias magnetic field accompanying rotation of a detection object in a cylindrical magnet having an open end while being held by the holding member, and a holding member And a filling step of filling a sealing material into a cylindrical magnet holding the magnetic detection element.

  In this way, by arranging the magnetic detection element held by the holding member in the cylindrical magnet and filling the magnet with the sealing material, the magnetism can be obtained without providing a housing or the like covering the opening of the magnet. A rotation detection device that can protect the detection element from the external environment can be manufactured. Therefore, the distance between the magnetic detection element and the detection target can be reduced by the amount of the housing that covers the magnet opening, and a rotation detection device with improved detection accuracy can be manufactured.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a front side sectional view showing a schematic configuration of a rotation detection device according to an embodiment of the present invention. FIG. 2 is a side sectional view showing a schematic configuration of the rotation detection device according to the embodiment of the present invention.

  The rotation detection device 100 shown in FIG. 1 and FIG. 2 measures the change of the bias magnetic field accompanying the rotation of the rotating body (detected body) 200 made of a magnetic material by the magnetic detection element 10 and determines the rotation state of the rotating body 200. To detect.

  A rotation detection device 100 shown in FIGS. 1 and 2 includes a magnetic detection element 10 that outputs a detection signal according to a change in a bias magnetic field accompanying rotation of a detection target, the magnetic detection element 10, and a magnet 40 that generates a bias magnetic field. Are connected to the base 20, the wire 30 for electrically connecting the magnetic detection element 10 and the terminal 22 for external output.

  The magnetic detection element 10 in the rotation detection device 100 of FIGS. 1 and 2 is mounted on a mounting portion 21 of the base 20 (corresponding to a holding member in claims of the present invention) in a bare chip state that is not resin-molded. The magnetic detection element 10 is electrically connected to the terminal 22 of the base 20 through the wire 30.

  The base 20 has a substantially rectangular mounting portion 21 on which the magnetic detection element 10 is mounted (held), a terminal 22 for outputting a detection signal detected by the magnetic detection element 10 to an external device, the mounting portion 21 and a magnet. A substantially circular pedestal portion 23 (corresponding to a pedestal member in the claims of the present invention) to which 40 is connected, and a connector portion 24 that is an interface with an external device and has a terminal 22 inside. The magnetic detection element 10 is mounted near the tip of the mounting portion 21, that is, at a position close to the rotating body 200. In the present embodiment, the mounting portion 21, the pedestal portion 23, and the connector portion 24 of the base 20 are integrally formed of a resin material, and the terminal 22 is insert-molded.

  The mounting portion 21, the pedestal portion 23, and the connector portion 24 are not limited to resin materials. Further, the base 20 is not limited to one in which the mounting portion 21, the pedestal portion 23, and the connector portion 24 are integrally formed of a resin material, and the terminal 22 is not insert-molded, and is provided separately. The mounting portion 21, the pedestal portion 23, and the connector portion 24 may be connected, and the terminal 22 may be connected. The mounting portion 21 is not limited to a substantially rectangular shape. Moreover, the base part 23 is not limited to a substantially circular shape.

  The magnet 40 is a cylindrical (permanent) magnet that is open at both ends and includes a through hole 41 (cylindrical in the present embodiment). As shown in FIGS. 1 and 2, the magnet 40 is arranged such that one end thereof is opposed to the rotating body 200 and the other end is connected to the pedestal portion 23 by an adhesive (not shown). . Thus, by connecting the magnet 40 and the pedestal portion 23, it is possible to suppress the sealing material 50 described later from leaking between the pedestal portion 23 and the magnet 40. Moreover, the leakage of the sealing material 50 can be further suppressed by connecting the magnet 40 and the pedestal portion 23 with an adhesive.

  In addition, the magnet 40 should just open the edge part which faces the rotary body 200 at least. In the present embodiment, the magnet 40 has been described using an example in which the end opposite to the end facing the rotating body 200 is connected to the pedestal 23, but the present invention is not limited thereto. It is not limited. If the magnet 40 accommodates the magnetic detection element 10 and the mounting portion 21 and can be filled with the sealing material 50, the object of the present invention can be achieved, and the pedestal portion 23 is provided at a location other than the end facing the rotating body 200. As long as it is connected.

  When connecting the pedestal 23 and the magnet 40, it is preferable to provide a positioning mechanism (for example, a protrusion or a mark) for positioning the base 20 and the magnet 40 on at least one of the base 20 and the magnet 40. By providing the positioning mechanism in this way, the base 20 and the magnet 40 are positioned, and the magnetic detection element 10 and the magnet 40 can be positioned.

  As shown in FIGS. 1 and 2, in the rotation detection device 100, the magnet 40 is connected to the pedestal portion 23, the magnetic detection element 10 is held in the magnet 40 by the mounting portion 21, and the space inside the magnet 40 is further increased. That is, the sealing material 50 is filled in (that is, the internal space surrounded by the cylindrical magnet 40 and the pedestal 23 and in which the magnetic detection element 10 is disposed).

  As shown in FIGS. 1 and 2, the base 20 (at least the mounting portion 21) and the magnetic detection element 10 are arranged in the magnet 40 without protruding outward from the end of the magnet 40. . By doing in this way, the magnet 40 acts as a protective cover for the base 20 (at least the mounting portion 21) and the magnetic detection element 10, thereby protecting the base 20 (at least the mounting portion 21) and the magnetic detection element 10. it can. Further, as shown in FIGS. 1 and 2, the sealing material 50 is filled in the magnet 40 so as to completely cover the base 20 (at least the mounting portion 21) and the magnetic detection element 10.

  Further, the pedestal 23 may be provided with a groove on the surface, and the groove 50 may be filled with the sealing material 50. That is, a groove portion may be provided in a portion of the pedestal portion 23 surrounded by the cylindrical magnet 40. By doing in this way, the anchor effect of the sealing material 50 can improve and adhesive force can be improved.

  As described above, by providing the sealing material 50 in the cylindrical magnet 40 in which the magnetic detection element 10 held by the mounting portion 21 is disposed, the magnetism is provided without providing a housing that covers the opening of the magnet 40. The detection element 10 can be protected from the external environment. Therefore, the distance between the magnetic detection element 10 and the rotating body 200 can be reduced by the amount that there is no housing that covers the opening of the magnet 40, and the detection accuracy can be improved.

  Here, a method for manufacturing rotation detection device 100 in the present embodiment will be described. 3A to 3D are drawings for each process showing a method of manufacturing the rotation detecting device according to the embodiment of the present invention.

  First, as shown in FIG. 3A, the base 20 is formed. The terminal 22 is loaded into a mold having a cavity having a predetermined shape, and a resin material is injected into the cavity.

  Next, as shown in FIG. 3B, the magnetic detection element 10 is mounted on the base 20 (mounting portion 21). The magnetic detection element 10 in a bare chip state is connected to the mounting portion 21 of the base 20 via an adhesive (not shown). Then, an electrode (not shown) of the magnetic detection element 10 and the terminal 22 are electrically connected by a wire 30.

  Next, as shown in FIG. 3C, the magnet 40 is connected to the base 20 (the pedestal portion 23). An adhesive or the like is placed on the pedestal portion 23 of the base 20 so that the magnetic detection element 10 mounted on the mounting portion 21 is disposed in the magnet 40, that is, the magnetic detection element 10 is surrounded by the cylindrical magnet 40. The magnet 40 is connected. At this time, it is preferable to connect the pedestal 23 and the magnet 40 in a state where the magnetic detection element 10 and the magnet 40 are positioned so as to have a predetermined positional relationship.

  Then, as shown in FIG. 3D, the sealing material 50 is filled. The sealing material 50 is filled in the internal space of the magnet 40, that is, the internal space surrounded by the cylindrical magnet 40 and the pedestal portion 23 and in which the magnetic detection element 10 is disposed.

  Thus, the housing which covers the opening part of the magnet 40 by arrange | positioning the magnetic detection element 10 hold | maintained at the mounting part 21 in the cylindrical magnet 40, and filling the sealing material 50 in the magnet 40. Thus, the rotation detection device 100 that can protect the magnetic detection element 10 from the external environment can be manufactured. Therefore, the distance between the magnetic detection element 10 and the rotating body 200 can be reduced by the amount of the housing that covers the opening of the magnet 40, and the rotation detection device 100 with improved detection accuracy can be manufactured.

  In the present embodiment, the magnetic detection element 10 is protected from the external environment by the sealing material 50 and the magnet 40 without providing a housing or the like, and therefore does not need to be separately mounted (inserted) in the housing or the like. Therefore, the sealing material 50 in the present embodiment does not need to be in a rigid state, and has a hardness and adhesive strength that do not flow out of the magnet 40 when the opening of the magnet 40 is directed in the direction of gravity. That's fine.

  For example, in the case of a magnetic detection element that is molded relatively hard (in a rigid state) with a thermosetting resin in consideration of external influences such as damage during assembly, stress is received by the molding resin. Therefore, there is a possibility that the output characteristics of the magnetic detection element may fluctuate depending on the cooling cycle during actual use.

  On the other hand, the magnetic detection element 10 in the present embodiment is in a state where it is molded with the sealing material 50 (gel-like member) in a relatively soft state. Therefore, since the magnetic detecting element 10 has a relatively soft sealing material 50 and can relieve stress, stress concentration due to a difference in thermal expansion coefficient of each component can be suppressed, and output characteristics may vary depending on a cooling cycle during actual use. Can also be reduced.

  However, the sealing material 50 is not limited to a gel-like member, and may be a thermosetting resin. As described above, when a thermosetting resin is used as the sealing material 50, the influence from the outside can be suppressed and the magnetic detection element 10 can be protected.

  Further, a groove portion may be provided on the surface of the pedestal portion 23 and the sealing material 50 may be filled in the groove portion. By doing in this way, the anchor effect of the sealing material 50 can improve and the adhesive force with the base part 23 can be improved.

  The sealing material 50 may be a material that seals the magnetic detection element 10 and fixes the base 20 (the pedestal portion 23) and the magnet 40.

(Modification 1)
Moreover, you may make it connect a base part and a magnet by press injection. FIG. 4 is a front view showing a schematic configuration of the rotation detection device according to the first modification of the present invention. FIG. 5 is a front cross-sectional view showing a schematic configuration of the rotation detection device according to Modification 1 of the present invention. In addition, in the modification 1 and the above-mentioned embodiment, since there are many common parts, description is abbreviate | omitted about a common part and it demonstrates focusing on a different part.

  As shown in FIG. 4, the base 20 a in the first modification example has a substantially rectangular mounting portion 21 a for mounting (holding) the magnetic detection element 10, and outputs a detection signal detected by the magnetic detection element 10 to an external device. Terminal 22a, mounting portion 21a, and a substantially circular pedestal portion 23a to which magnet 40 is connected (corresponding to a pedestal member in the claims of the present invention), an external device and a connector portion having terminal 22a inside 24a and a protrusion 25a that is a press-fit portion for fixing the magnet 40. The mounting portion 21a, the terminal 22a, and the connector portion 24a are the same as the mounting portion 21, the terminal 22, and the connector portion 24 in the above-described embodiment (similar), and thus description thereof is omitted.

  The protrusion 25a is a press-fit portion that has a shape corresponding to the opening shape (cross-sectional shape) of the magnet 40 and protrudes from the pedestal portion 23a toward the direction to which the magnet 40 is connected. Further, as shown in FIG. 5, the protrusions 25 a are provided at intervals wider than the inner diameter (inner diameter) of the magnet 40. Then, as shown in FIG. 5, the magnet 40 is press-fitted into the protrusion 25a and connected to the pedestal 23a.

  By doing in this way, the base part 23a and the magnet 40 can be easily adhered, and further, the sealing material 50 can be prevented from leaking between the base part 23a and the magnet 40.

  As for the press-fit portion, in addition to providing the protrusion 25a as described above, a recessed portion or a through hole having a shape smaller than the thickness of the magnet 40 and corresponding to the opening shape (cross-sectional shape) of the magnet 40 is provided in the pedestal portion. You may make it provide. Then, the magnet 40 is press-fitted into the recess or the through hole. Thus, even if it is a recessed part or a through-hole, it becomes easy to contact | adhere a base part and a magnet, Furthermore, it can suppress that the sealing material 50 leaks from between a base part and a magnet 40. FIG.

  Note that an adhesive may be provided between the pedestal portion and the magnet 40 even when the magnet 40 is press-fitted into the protrusion 25a, the concave portion, and the through-hole that are the press-fitting portions. By doing in this way, a base part and the magnet 40 can be stuck further, and it can suppress that the sealing material 50 leaks from between a base part and the magnet 40. FIG.

(Modification 2)
Moreover, the claw part 25b for connecting with the cylindrical magnet 40b may be provided in the base part 23b, and the recessed part corresponding to the claw part may be provided in the magnet. FIG. 6 is a front cross-sectional side view showing a schematic configuration of the rotation detection device according to the second modification of the present invention. In Modification 2 and the above-described embodiment and Modification 1, since there are many common parts, description of the common parts will be omitted, and different parts will be described mainly.

  As shown in FIG. 6, the base 20a includes a claw portion 25b on a pedestal portion 23b. The claw portion 25b is provided on a cylindrical protrusion provided on the surface of the pedestal portion 23b (a surface of a portion disposed in the magnet 40b) or an outer peripheral portion of a columnar protrusion. Further, the claw portion 25b may be provided over the entire circumference of the outer peripheral portion, but may be provided at a plurality of locations equally on the outer peripheral portion.

  On the other hand, the magnet 40b includes a concave portion 41b corresponding to the claw portion 25b, and a tapered portion 42b at the end. More specifically, the tapered portion 42b at the end of the magnet 40b is provided with a recess 41b.

  And the base part 23b and the magnet 40b are connected by inserting the nail | claw part 25b in the recessed part 41b. By doing in this way, the base part 23b and the magnet 40b can be firmly fixed.

  Further, by providing the tapered portion 42b at the end of the magnet 40b, the claw portion 25b can be easily inserted (fitted) into the concave portion 41b of the magnet 40b.

(Modification 3)
Moreover, you may make it provide the taper part 25c in the base part 23c. FIG. 7 is a front cross-sectional side view showing a schematic configuration of a rotation detection device according to Modification 3 of the present invention. In Modification 3 and the above-described embodiment and Modifications 1 and 2, since there are many common parts, description of common parts will be omitted, and different parts will be mainly described.

  As shown in FIG. 7, the base 20a includes a claw portion 24c on the pedestal portion 23c, and a tapered portion 25c at the end of the claw portion 24c. The tapered portion 25c has a diameter that increases in the direction in which the magnet 40c is inserted. On the other hand, the magnet 40c includes a recess 41c corresponding to the claw portion 24c.

  Thus, by providing the taper portion 25c on the claw portion 24c of the base portion 23c, the claw portion 24c can be easily inserted (fitted) into the concave portion 41c of the magnet 40c.

  In Modification 2 and Modification 3, the pedestal portion is provided with a claw portion for connecting to a cylindrical magnet, and the cylindrical magnet is described using an example in which a concave portion corresponding to the claw portion is provided. The present invention is not limited to this. For example, a cylindrical magnet includes a claw portion for connecting to a pedestal portion, the pedestal portion is provided with a cylindrical protrusion or a columnar protrusion, and a recess corresponding to the claw portion on the outer peripheral portion of the protrusion. The object of the present invention can also be achieved by providing the above.

  Also in this case, at least one of the claw portion of the cylindrical magnet and the protrusion of the pedestal portion may have a tapered shape. This also makes it easy to fit the claw portion of the magnet into the recess of the pedestal portion.

  Moreover, although the above-mentioned embodiment and the modifications 1 to 3 can be implemented individually, they can be implemented in combination as appropriate. For example, as an example, a combination of Modification 2 and Modification 3 may be implemented to provide tapered portions on both the claw portion of the pedestal portion and the pedestal portion side end portion of the magnet.

It is a front side sectional view showing a schematic structure of a rotation detector in an embodiment of the invention. It is side surface sectional drawing which shows schematic structure of the rotation detection apparatus in embodiment of this invention. (A)-(d) is drawing according to process which shows the manufacturing method of the rotation detection apparatus in embodiment of this invention. It is a front view which shows schematic structure of the rotation detection apparatus in the modification 1 of this invention. It is front side sectional drawing which shows schematic structure of the rotation detection apparatus in the modification 1 of this invention. It is a front view side sectional view which shows schematic structure of the rotation detection apparatus in the modification 2 of this invention. It is a front view side sectional view which shows schematic structure of the rotation detection apparatus in the modification 3 of this invention.

Explanation of symbols

10 Magnetic detection element, 20, 20a base, 21, 21a mounting part, 22, 22a terminal, 23, 23a pedestal part, 24, 24a connector part, 25a protrusion, 30 wire, 40 magnet, 41 through hole, 50 sealing Material, 100 rotation detecting device, 200 rotating body (detected body)

Claims (13)

A rotation detection device for detecting a rotation state of a detected object,
A cylindrical magnet that generates a bias magnetic field and has an end that faces at least the object to be detected; and
A magnetic detection element that outputs a detection signal corresponding to a change in the bias magnetic field accompanying the rotation of the detected object;
A holding member for holding the magnetic detection element in the cylindrical magnet;
A sealing material filled in the cylindrical magnet in which the magnetic detection element is held by the holding member;
A rotation detection device comprising:   The rotation detection device according to claim 1, further comprising a pedestal member to which a portion different from an end portion of the cylindrical magnet facing the detection target is connected.   The rotation detection device according to claim 2, wherein the pedestal member includes a press-fitting portion at a portion to which the cylindrical magnet is connected, and the cylindrical magnet is press-fitted into the press-fitting portion.   The rotation detection device according to claim 2, wherein the pedestal member and the cylindrical magnet are connected via an adhesive.   The rotation detection device according to any one of claims 2 to 4, wherein the holding member is connected to the pedestal member.   The rotation detection device according to claim 2, wherein the pedestal member includes a positioning mechanism for the cylindrical magnet.   The rotation detection device according to claim 2, wherein the pedestal member includes a groove portion on a surface thereof, and the groove portion is filled with the sealing material.   The rotation detection device according to any one of claims 1 to 7, wherein the holding member and the magnetic detection element are disposed inside an end face of the cylindrical magnet.   The rotation detection device according to claim 1, wherein the sealing material is made of a thermosetting resin.   The rotation detection apparatus according to claim 1, wherein the sealing material is a gel-like member.   The said base member is provided with the nail | claw part for connecting with the said cylindrical magnet, The said cylindrical magnet is provided with the recessed part corresponding to the said nail | claw part. The rotation detection device according to one item.   The rotation detection device according to claim 11, wherein at least one of the claw portion of the pedestal member and the pedestal side end portion of the cylindrical magnet has a tapered shape. A method of manufacturing a rotation detection device for detecting a rotation state of a detection object,
A bias magnetic field is generated, and a detection signal corresponding to a change in the bias magnetic field accompanying rotation of the detected body is output in at least a cylindrical magnet whose end facing the detected body is open. An arrangement step of arranging the magnetic detection element in a state of being held by the holding member;
A filling step of filling a sealing material into the cylindrical magnet in which the magnetic detection element is held by the holding member;
A method for manufacturing a rotation detecting device.

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