JP2020198667A - Non-contact power transmission device - Google Patents

Abstract

To provide a non-contact power transmission device in which a coil and a holder holding the coil can be fixed without any adhesive agent.SOLUTION: A non-contact power transmission device 1 includes: a first holder 21 provided with a first coil 18; a second holder 60 provided with a second coil 19; and a first ball bearing 13 connecting the first holder 21 and the second holder 60 in a relatively rotatable manner about an axis L of the first coil 18. The first holder 21 includes a first coil holding portion 37 holding the first coil 18. The first coil holding portion 37 includes: a circular first fit portion 41 fitted to a center hole of the first coil 18; a first support portion 42 having an annular first support surface 42a supporting, on the outer circumferential side of the first fit portion 41, the first coil 18 from a side opposite to the second coil 19; and a contact portion 49 coming into contact with a part in the circumferential direction, of the first coil 18 being supported by the first support surface 42a, from the second coil 19 side.SELECTED DRAWING: Figure 2

Description

The present invention relates to a non-contact power transmission device that transmits power between a first coil and a second coil, respectively, of which two members that rotate relative to each other are fixed.

Such a non-contact power transmission device is described in Patent Document 1. The non-contact power transmission device of the same document is held in a first holder in which a first through hole is formed, a first coil held in the first holder and orbiting around the first through hole, and a first holder. A second holder facing the second through hole and having a second through hole formed therein, and a second coil held by the second holder so as to face the first coil and orbiting around the second through hole. Be prepared. Further, the non-contact power transmission device is arranged concentrically with respect to the first through hole and the second through hole inside the first through hole, and a radial connecting the first holder and the second holder so as to be relatively rotatable. Has bearings. The first coil is a flat coil wound in an annular shape, and is arranged so as to revolve around the first through hole. The first coil is fixed to the annular first core held by the first holder with an adhesive.

Japanese Patent Application No. 2015-201696

When power is transmitted between the two coils, each coil generates heat. Therefore, when an adhesive is used to fix the coil and the holder, the coil may fall off from the holder due to deterioration of the adhesive due to heat. When an adhesive is used to fix the coil and the holder, an adhesive application step of applying the adhesive to the coil or the holder at the time of manufacturing, an arrangement step of positioning the coil on the holder, and an adhesive layer are performed. An adhesive drying step is required in which the adhesive is dried after the coil and the holder are joined to each other. Therefore, there is a problem that the manufacturing process of the non-contact power transmission device increases.

In view of these points, an object of the present invention is to provide a non-contact power transmission device capable of fixing a coil and a holder holding the coil without using an adhesive.

In order to solve the above problems, the present invention comprises a first holder provided with a first coil and a second holder provided with a second coil coaxial with the first coil and facing the first coil with a gap. A connection mechanism for connecting the first holder and the second holder so as to be relatively rotatable about the axis of the first coil and the second coil, and the first coil and the second coil. In a non-contact power transmission device for transmitting power between the first holders, the first holder includes a first coil holding portion for holding the first coil, and the first coil holding portion is a center hole of the first coil. A first fitting portion to be fitted to the first fitting portion, and a first support portion having an annular first support surface that supports the first coil from a side opposite to the second coil on the outer peripheral side of the first fitting portion. The first coil is provided with a contact portion that comes into contact with a part of the first coil in the circumferential direction supported by the first support surface from the side of the second coil.

According to the present invention, the first coil is supported by the first support surface of the first coil holding portion in a state where the first fitting portion of the first coil holding portion of the first holder is fitted in the center hole. .. Therefore, the first coil is positioned in the first holder in the radial direction with respect to the first fitting portion. Further, the first holder is made immovable in the radial direction by the first fitting portion. Further, the first coil holding portion includes a contact portion that contacts the first coil from the side opposite to the first support surface. Therefore, the first coil is positioned in the axial direction of the first coil by the first support surface and the contact portion. Further, the first coil is made immovable in the axial direction by the first support surface and the contact portion. Therefore, the first coil can be fixed to the first holder without using an adhesive.

In the present invention, the first holder is made of resin, the first coil holding portion includes a first annular portion located on the outer peripheral side of the first support portion, and the first annular portion is in the circumferential direction. Each hook is provided with hooks at a plurality of locations separated by, and each hook is a pillar portion inclined inward toward the side of the second coil from the first annular portion and an end of the pillar portion on the side of the second coil. It is provided with a claw portion protruding from the inner peripheral side, the claw portion overlaps with the first support surface when viewed from the axial direction, and the pillar portion can be elastically deformed in a direction intersecting the axial line. , The claw portion can be the contact portion. In this way, when the first coil is supported on the first support surface of the first coil holding portion, the first coil can be brought into contact with the claw portion to elastically deform the pillar portion to the outer peripheral side. This makes it easy to mount the first coil on the first support surface. Further, when the first coil is placed on the first support surface, the pillar portion of the hook elastically returns to the original shape, and the claw portion abuts on the side opposite to the first support surface of the first coil. Therefore, it is easy to sandwich the first coil between the first support surface and the abutting portion to make it immovable in the axial direction.

In the present invention, the first support portion includes urging portions for urging the first coil toward the side where the second coil is located at a plurality of locations in the circumferential direction of the first support portion. The urging portion has a support portion portion that is divided into tongue pieces by a slit that penetrates the first support portion in the axial direction, and a support portion portion that is provided on the support portion portion and projects to the side where the second coil is located. It is desirable that the support portion is provided with a protrusion and is elastically deformable in the axial direction. In this way, when the first coil is supported on the first support surface, the urging portion can urge the first coil toward the side of the second coil. As a result, since the first coil is urged to the contact portion, it is possible to prevent the first coil from rattling between the first support surface and the contact portion. Further, since the first coil is urged in the direction approaching the second coil by the urging force of the urging portion, the first coil is separated from the second coil between the first support surface and the abutting portion. It can be prevented from being placed in a position. As a result, it is possible to prevent the gap between the first coil and the second coil from becoming large and the power transmission efficiency from being lowered.

In the present invention, it is desirable that each hook and each urging portion are provided at different angular positions about the axis. In this way, when molding the first resin holder having the plurality of hooks and the plurality of urging portions, the first holder can be molded with high accuracy.

In the present invention, the second holder has an annular plate member fixed to the second holder, and the second holder has a second coil holding portion at a position overlapping the first coil holding portion when viewed from the axial direction. The second coil holding portion includes a second fitting portion that fits into the central hole of the second coil, and the second coil is opposite to the first coil on the outer peripheral side of the second fitting portion. A second support portion having an annular second support surface that supports from the side is provided, and the plate member is fixed to the second fitting portion and is fixed to the opening edge of the central hole in the second coil. It is desirable that the plate member and the hook do not overlap when viewed from the axial direction by abutting from the side of the two coils. In this way, the second coil is supported by the second support surface of the second coil holding portion in a state where the second fitting portion of the second coil holding portion of the second holder is fitted in the center hole. .. Therefore, the second coil is positioned on the second holder with reference to the second fitting portion. Further, the second holder is made immovable in the radial direction by the second fitting portion. Further, a plate member is fixed to the second coil holding portion, and the plate member comes into contact with the second coil from the side opposite to the second support surface. Therefore, the second coil is held by the second coil holding portion in a state where it cannot move in the axial direction by the second support surface and the abutting portion. Further, the plate member and the hook do not overlap when viewed from the axial direction. Therefore, even if the contact portion is located on the side of the second coil of the first coil and the plate member is located on the side of the first coil of the second coil, the first coil and the second coil are aligned in the axial direction. It is easy to get close.

In the present invention, a first annular magnetic shield sheet and a second annular magnetic shield sheet made of a magnetic material are provided, and the first annular magnetic shield sheet is interposed between the first support surface and the first coil, and the second ring is provided. It is desirable that the annular magnetic shield sheet is interposed between the second support surface and the second coil. In this way, it is possible to suppress the magnetic coupling between the first coil and the second coil from being affected by the magnetic field from the outside in the axial direction.

In the present invention, there is a first tubular magnetic shield sheet and a second tubular magnetic shield sheet made of a magnetic material, and the second holder has an axial direction inside the second coil toward the side of the first coil. The second fitting includes an extending shaft portion, and the connection mechanism includes an annular bearing held on the inner peripheral side of the first coil in the first holder to support the shaft portion from the outer peripheral side. The portion is provided integrally with the shaft portion, the first fitting portion is tubular, the bearing is held inside the first fitting portion, and the first tubular magnetic shield sheet. Is interposed between the first fitting portion and the first coil, and it is desirable that the second tubular magnetic shield sheet is interposed between the second fitting portion and the second coil. In this way, it is possible to prevent the magnetic coupling of the first coil and the second coil from being affected by the magnetic field from the inner peripheral side. Therefore, as the bearing, a metal ball bearing or the like can be adopted.

According to the present invention, the first coil holding portion has a first fitting portion that fits into the center hole of the first coil and an outer peripheral side of the first fitting portion with the first coil on the opposite side of the second coil. It is provided with a first support portion having an annular first support surface supported by the first support surface, and an abutting portion that contacts a part of the first coil supported by the first support surface in the circumferential direction from the side of the second coil. Therefore, the first coil can be fixed to the first holder without using an adhesive.

It is a perspective view of the non-contact power transmission apparatus to which this invention is applied. It is sectional drawing of the non-contact power transmission apparatus. It is an exploded perspective view when the non-contact power transmission apparatus is seen from the side of the 1st holder. It is an exploded perspective view when the non-contact power transmission device is seen from the side of the exterior cover. It is an exploded perspective view of a fixed unit. It is an exploded perspective view of a movable unit. It is an exploded perspective view of the 2nd holder. It is explanatory drawing of the optical path of the 1st signal light and the optical path of the 2nd signal light.

Hereinafter, a non-contact power transmission device to which the present invention is applied will be described with reference to the drawings.

(overall structure)
FIG. 1 is a perspective view of a non-contact power transmission device to which the present invention is applied. FIG. 2 is a cross-sectional view of the non-contact power transmission device. FIG. 3 is an exploded perspective view of the non-contact power transmission device when viewed from the side of the first holder. FIG. 4 is an exploded perspective view of the non-contact power transmission device when viewed from the side of the exterior cover.

As shown in FIG. 1, the non-contact power transmission device 1 includes a fixed unit 2 having a rectangular parallelepiped shape as a whole, and an exterior cover 3 covered on one side of the fixed unit 2. The exterior cover 3 includes a cylindrical portion 5 and an annular plate portion 6 extending from an end of the cylindrical portion 5 opposite to the fixing unit 2 to the inner peripheral side. Further, as shown in FIG. 3, the cover projects toward the fixing unit 2 at a position which is an edge portion on the inner peripheral side of the annular plate portion 6 and is separated from the central hole of the annular plate portion 6 toward the outer peripheral side. The cover side tubular portion 7 is provided.

As shown in FIGS. 2 to 4, the movable unit 10 is housed inside the exterior cover 3. The movable unit 10 includes a first shaft portion 11 projecting toward the fixed unit 2, and a second shaft portion 12 projecting toward the cover side tubular portion 7 of the exterior cover 3. The first shaft portion 11 and the second shaft portion 12 are coaxial. The second shaft portion 12 projects from the central hole of the annular plate portion 6 to the outside of the exterior cover 3.

Here, as shown in FIG. 2, the first shaft portion 11 is rotatably supported by the fixed unit 2 via the first ball bearing 13 (connection mechanism / bearing) held by the fixed unit 2. The second shaft portion 12 is rotatably supported by the exterior cover 3 via a second ball bearing 14 held inside the cover side tubular portion 7. Therefore, the movable unit 10 can rotate around the axes of the first shaft portion 11 and the second shaft portion 12. In the second ball bearing 14, the outer ring is fixed to the cover side tubular portion 7, and the inner ring is fixed to the second shaft portion 12. In the following description, the direction along the axis L of the first shaft portion 11 and the second shaft portion 12 of the movable unit 10 is defined as the axial direction X. Further, in the axial direction X, the side where the fixed unit 2 is located is referred to as the first direction X1, and the side where the exterior cover 3 is located is referred to as the second direction X2.

As shown in FIGS. 2 and 4, the fixed unit 2 includes a first coil 18 facing the movable unit 10 in the axial direction X. The movable unit 10 includes a second coil 19 facing the first coil 18 in the axial direction X. The first coil 18 and the second coil 19 face each other with a predetermined gap in the axial direction X. The non-contact power transmission device 1 transmits power from the first coil 18 to the second coil 19 in a non-contact manner by electromagnetic induction.

Here, the non-contact power transmission device 1 is used, for example, in a versa writer or a 3D hologram display when supplying power to a rotating light emitter. When the non-contact power transmission device 1 is used for a versa writer or a 3D hologram display, a drive unit that rotationally drives the movable unit 10 is connected to a portion of the second shaft portion 12 that protrudes from the exterior cover 12. Further, a rotation display unit including a plurality of LEDs as a light emitting body is connected to the second shaft portion 12. In the non-contact power transmission device 1, the power transmitted from the first coil 18 of the fixed unit 2 to the second coil 19 of the movable unit 10 is supplied from the movable unit 10 to the rotation display unit. According to the non-contact power transmission device 1 of this example, power can be supplied to the rotation display unit even when the rotation speed of the rotation display unit is 2000 rpm.

(Fixed unit)
FIG. 5 is an exploded perspective view of the fixed unit 2. In FIG. 5, the fixed unit 2 is viewed from the side of the second direction X2. As shown in FIGS. 4 and 5, the fixing unit 2 includes a first coil 18 and a first holder 21 that holds the first coil 18. Further, as shown in FIG. 5, the fixing unit 2 includes a first substrate 22 arranged in the first direction X1 of the first holder 21.

An opening 23 is provided in a portion of the first substrate 22 through which the axis L passes. As shown in FIG. 2, the first light emitting element 25A is inserted into the opening 23 from the side of the substrate surface 22a in the first direction X1 of the first substrate 22. The first light emitting element 25A is fixed to the first substrate 22. The first light emitting element 25A is an element for performing the first optical communication by the first signal light S1 between the fixed unit 2 and the movable unit 10. Further, the second light receiving element 26B is inserted into the opening 23 from the side of the substrate surface 22a in the first direction X1 of the first substrate 22. The second light receiving element 26B is fixed to the first substrate 22. The second light receiving element 26B is an element for performing a second optical communication by the second signal light S2 between the fixed unit 2 and the movable unit 10. The first light emitting element 25A is located on the axis L. The second light receiving element 26B is arranged at a position deviated from the axis L radially outward by a predetermined distance. As shown in FIG. 5, when the first substrate 22 is viewed from the second direction X2, the first light emitting element 25A and the second light receiving element 26B are visible through the opening 23.

Further, the fixing unit 2 includes a metal plate 29 that supports the first substrate 22 via an insulating sheet 28 in the first direction X1 of the first substrate 22. The plate 29 is fixed to the first holder 21 by screws. As a result, the first substrate 22 is fixed to the first holder 21.

The first holder 21 has a rectangular parallelepiped shape as a whole. As shown in FIGS. 2 and 5, the first holder 21 includes a rectangular frame plate portion 31 when viewed from the axial direction X. Further, the first holder 21 includes a large-diameter tubular portion 32 extending in the axial direction X inside the frame plate portion 31. A part of the large-diameter tubular portion 32 in the circumferential direction is integrally formed with the frame plate portion 31. Further, the first holder 21 extends from the upper plate portion 33 connecting the end portions of the frame plate portion 31 and the large diameter cylinder portion 32 in the second direction X2 and the lower end edge of the large diameter cylinder portion 32 to the inner peripheral side. An annular plate portion 34 is provided. In the first holder 21, a small-diameter tubular portion 35 projecting upward is provided at an end portion on the inner peripheral side of the annular plate portion 34 and at a position separated from the central hole of the annular plate portion 34 toward the outer peripheral side. There is.

As shown in FIG. 4, the circular recess defined by the large-diameter tubular portion 32 and the annular plate portion 34 is the first coil holding portion 37 that holds the first coil 18. As shown in FIG. 5, the first coil holding portion 37 includes a tubular first fitting portion 41 that fits into the central hole of the first coil 18, and a first coil on the outer peripheral side of the first fitting portion 41. A first support portion 42 having an annular first support surface 42a that supports 18 from the side of the first direction X1 and a first annular portion 43 located on the outer peripheral side of the first support portion 42 are provided. The first fitting portion 41 is a small diameter tubular portion 35. The first coil 18 is placed on the first support surface 42a with the first fitting portion 41 inserted in the central hole of the first coil 18. The first support surface 42a is a surface portion of the upper surface of the annular plate portion 34 that overlaps with the first coil 18 when the state in which the first coil 18 is placed on the annular plate portion 34 is viewed from the axial direction X. .. The first annular portion 43 is a portion inside the large-diameter tubular portion 32 and located on the outer peripheral side of the first support surface 42a.

The first annular portion 43 is provided with hooks 45 at a plurality of locations separated in the circumferential direction. In this example, hooks 45 are provided at three positions separated by 120 ° around the axis L. Each hook 45 has a pillar portion 45a extending inward from the first annular portion 43 toward the side of the second coil 19, and a claw protruding inward from the end of the pillar portion 45a on the side of the second coil 19. The unit 45b is provided. In this example, the pillar portion 45a penetrates the opening provided in the annular plate portion 34 from the portion of the first annular portion 43 located in the first direction X1 with respect to the annular plate portion 34, and is formed by the annular plate portion 34. It projects in the second direction X2. The pillar portion 45a is elastically deformable in the direction intersecting the axis L. The claw portion 45b projects to a position where it overlaps with the first support surface 42a when viewed from the axial direction X.

The first support portion 42 is provided with urging portions 47 that urge the first coil 18 toward the side where the second coil 19 is located at a plurality of locations in the circumferential direction of the first support surface 42a. In this example, urging portions 47 are provided at three locations separated by 120 ° around the axis L. Each urging portion 47 is provided with a support portion 47a partitioned in a tongue-like shape by a slit 48 penetrating the first support portion 42 in the axial direction X, and a second coil 19 provided in the support portion 47a. It is provided with a protrusion 47b protruding to the side of the coil. More specifically, each slit 48 provided in the first support portion 42 has a pair of first slit portions 48a extending in parallel toward the outer peripheral side and an outer circumference of the pair of first slit portions 48a extending in the circumferential direction. It is provided with a second slit portion 48b that connects the side end portions. The support portion 47a partitioned by the slit 48 has a rectangular shape that is long in the radial direction when viewed from the axial direction X. The outer peripheral side of the support portion 47a is elastically deformable in the axial direction X. The protrusion 47b is provided at an end portion on the outer peripheral side of the support portion 47a. The protrusion 47b projects in the second direction X2 from the first support surface 42a in a state where the support portion 47a is not elastically deformed.

The urging portion 47 and the hook 45 are provided at different angular positions around the axis L. In this example, the urging portion 47 and the hook 45 are displaced by 60 ° around the axis L. That is, the angle between the urging portions 47 adjacent to each other in the circumferential direction and the hook 45 is 60 °.

Here, the pillar portion 45a of the hook 45 is elastically deformable. Therefore, when the first coil 18 is supported on the first support surface 42a of the first coil holding portion 37, if the first coil 18 is brought into contact with the claw portion 45b, the pillar portion 45a is elastically deformed to the outer peripheral side. be able to. Therefore, it is easy to mount the first coil 18 on the first support surface 42a. Further, when the first coil 18 is placed on the first support surface 42a, the pillar portion 45a elastically returns to its original shape, and the claw portion 45b comes into contact with the side of the first coil 18 opposite to the first support surface 42a. .. Therefore, as shown in FIGS. 2 and 4, the claw portion 45b of the hook 45 abuts on a portion of the first coil 18 supported by the first support surface 42a in the circumferential direction from the second direction X2. It becomes.

Further, in the urging portion 47 of the first support portion 42, when the first coil 18 is supported by the first support surface 42a, the protrusion 47b comes into contact with the first coil 18, so that the support portion 47a is the first. Elastically deforms in direction X1. Therefore, the urging portion 47 urges the first coil 18 toward the side of the second coil 19 by the elastic force of the supporting portion portion 47a. As a result, the first coil 18 is urged to the claw portion 45b (contact portion 49) of the hook 45. Therefore, the first coil 18 is prevented from rattling between the first support surface 42a and the contact portion 49.

In this example, the first tubular magnetic shield sheet 51 made of a magnetic material is interposed between the first fitting portion 41 and the first coil 18. That is, in the first coil 18, the first fitting portion 41 in a state where the first tubular magnetic shield sheet 51 is attached to the outer peripheral surface is inserted into the center hole. Further, in this example, the first annular magnetic shield sheet 52 made of a magnetic material is interposed between the first coil 18 and the first support surface 42a. That is, the first coil 18 is placed on the first support surface 42a after the first annular magnetic shield sheet 52 is laid on the first support surface 42a.

Here, the first holder 21 holds the first ball bearing 13 inside the tubular first fitting portion 41 (small diameter tubular portion 35). As shown in FIG. 2, in the first ball bearing 13, the inner ring 13a is fixed to the outer peripheral surface of the first shaft portion 11 of the movable unit 10, and the outer ring 13b is fixed to the inner peripheral surface of the first fitting portion 41. ..

(Movable unit)
FIG. 6 is an exploded perspective view of the movable unit 10. In FIG. 6, the movable unit 10 is viewed from the side of the first direction X1. FIG. 7 is an exploded perspective view of the second holder. As shown in FIGS. 3 and 6, the movable unit 10 has an annular shape fixed to the second coil 19, the second holder 60 holding the second coil 19, and the first direction X1 of the second holder 60. A plate member 61 is provided. Further, the movable unit 10 includes a second substrate 62 arranged in the second direction X2 of the second holder 60, and a cover 63 that covers the second holder 60 from the second direction X2 and covers the second substrate 62. To be equipped.

As shown in FIG. 6, an opening 65 is provided in a portion of the second substrate 62 through which the axis L passes. As shown in FIG. 2, the first light receiving element 25B is inserted into the opening 65 from the side of the substrate surface 62a in the second direction X2 of the second substrate 62. The first light receiving element 25B is fixed to the substrate surface 62a of the second substrate 62. The first light receiving element 25B is an element for performing the first optical communication by the first signal light S1 between the fixed unit 2 and the movable unit 10. The first light receiving element 25B is located on the axis L. Further, on the substrate surface 62a in the second direction X2 of the second substrate 62, a second light emitting element 26A for performing a second optical communication by the second signal light S2 between the fixed unit 2 and the movable unit 10 is provided. Two are fixed. Each of the second light emitting elements 26A is arranged at a position deviated from the axis L by a predetermined distance radially outward. The two second light emitting elements 26A are arranged at positions separated by 180 ° around the axis L. As shown in FIG. 6, when the second substrate 62 is viewed from the first direction X1, the first light receiving element 25B and the two second light emitting elements 26A are visible through the opening 65.

As shown in FIG. 4, the cover 63 extends inward from the end of the tubular body portion 68 in which the end portion of the first direction X1 abuts on the second holder 60 and the end of the body portion 68 in the second direction X2. The outer annular plate portion 69, the tubular portion 70 extending from the inner peripheral end edge of the outer annular plate portion 69 in the first direction X1, and the inner annular plate extending from the end of the tubular portion 70 in the first direction X1 to the inner peripheral side. A portion 71 and a tubular second shaft portion 12 extending in the second direction X2 from the inner peripheral edge of the inner annular plate portion 71 are provided. The tubular portion 70, the inner annular plate portion 71, and the second shaft portion 12 partition the annular recess. As shown in FIG. 2, the cover-side tubular portion 7 of the exterior cover 3 is inserted into the annular recess from the second direction X2. The second ball bearing 14 connects between the cover-side tubular portion 7 and the second shaft portion 12 inside the tubular portion 70.

As shown in FIG. 6, the second holder 60 has a large-diameter annular plate portion 75 and a large-diameter annular plate portion 75 coaxially with the large-diameter annular plate portion 75 from the side of the second direction X2 toward the side of the first direction X1. A medium-diameter cylindrical portion 76 extending in the first direction X1 from the end portion on the inner peripheral side of the plate portion 75, and a medium-diameter annular plate portion extending from the end portion of the medium-diameter cylindrical portion 76 in the first direction X1 toward the inner peripheral side. 77 and a first shaft portion 11 extending from the inner peripheral end of the medium-diameter annular plate portion 77 coaxially with the medium-diameter annular plate portion 77 in the first direction X1 and the second direction X2.

The large-diameter annular plate portion 75, the medium-diameter cylindrical portion 76, and the medium-diameter annular plate portion 77 form a second coil holding portion 80 that holds the second coil 19. The second coil holding portion 80 has a tubular second fitting portion 81 that fits into the central hole of the second coil 19, and a second coil 19 on the outer peripheral side of the second fitting portion 81 in the second direction X2. A second support portion 82 having an annular second support surface 82a that supports from the side is provided. The second fitting portion 81 includes a medium-diameter cylindrical portion 76 and a medium-diameter annular plate portion 77. The second support portion 82 is a large-diameter annular plate portion 75, and the second support surface 82a is an end surface of the large-diameter annular plate portion 75 in the first direction X1. The second coil 19 is placed on the second support surface 82a with the second fitting portion 81 inserted in the central hole of the second coil 19.

As shown in FIG. 6, the second support portion 82 is provided with urging portions 83 for urging the second coil 19 toward the side where the first coil 18 is located at a plurality of locations in the circumferential direction. .. In this example, urging portions 47 are provided at three locations separated by 120 ° around the axis L. Each urging portion 47 is provided with a support portion 83a partitioned in a tongue-like shape by a slit 84 penetrating the second support portion 82 in the axial direction X, and a first coil 18 is located in the support portion 83a. It is provided with a protrusion 83b protruding to the side. More specifically, each slit 84 provided in the second support portion 82 has a pair of first slit portions 84a extending in parallel toward the outer peripheral side and an outer circumference of the pair of first slit portions 84a extending in the circumferential direction. It is provided with a second slit portion 84b that connects the side end portions. The support portion 83a partitioned by the slit 84 has a rectangular shape that is long in the radial direction when viewed from the axial direction X. The outer peripheral side of the support portion 83a is elastically deformable in the axial direction X. The protrusion 83b is provided at an end portion on the outer peripheral side of the support portion 83a. The protrusion 83b projects in the first direction X1 from the second support surface 82a in a state where the support portion 83a is not elastically deformed.

The plate member 61 has a larger outer diameter than the second fitting portion 81. Further, the outer dimension of the plate member 61 is larger than the inner diameter of the center hole of the second coil 19. The plate member 61 is fixed to the end surface (medium diameter annular plate portion 77) of the second fitting portion 81 by two screws 85. As shown in FIG. 3, the plate member 61 is fixed to the second fitting portion 81 and abuts on the opening edge of the central hole in the second coil 19 supported by the first support surface 42a from the first direction X1. ..

In this example, a second tubular magnetic shield sheet 87 made of a magnetic material is interposed between the second fitting portion 81 and the second coil 19. That is, in the second coil 19, the second fitting portion 81 in which the second tubular magnetic shield sheet 87 is attached to the outer peripheral surface is inserted into the center hole. Further, in this example, a second annular magnetic shield sheet 88 made of a magnetic material is interposed between the second coil 19 and the second support surface 82a. That is, the second coil 19 is placed on the second support surface 82a after the second annular magnetic shield sheet 88 is laid on the second support surface 82a.

Here, as shown in FIG. 7, the second holder 60 includes a columnar member 91 that penetrates the first shaft portion 11 in the axial direction X, and a holder body member 92 that surrounds the columnar member 91 from the outer peripheral side. As a result, the first shaft portion 11 includes a columnar portion 11a made of the columnar member 91 and a tubular portion 11b made of the holder body member 92. The tubular portion 11b surrounds the columnar portion 11a from the outer peripheral side.

The axis L penetrates the columnar member 91. The columnar member 91 includes a columnar portion 91a having a cylindrical shape, and a bent portion 91b that protrudes outward from the end portion of the columnar member 91 in the second direction X2 and bends in the second direction X2. The columnar member 91 is inserted into the central hole 92a of the holder body member 92 from the second direction X2. The bent portion 91b comes into contact with the upper surface of the holder body member 92. Further, the second substrate 62 comes into contact with the upper surface of the bent portion 91b.

Both the columnar member 91 and the holder body member 92 have translucency. That is, the second holder 60 has translucency. In this example, the refractive index of the columnar member 91 and the refractive index of the holder body member 92 are different. That is, in the first shaft portion 11, the refractive index of the columnar portion 11a and the refractive index of the tubular portion 11b are different.

As shown in FIG. 2, in the movable unit 10, the first shaft portion 11 is inserted inside the first ball bearing 13 of the fixed unit 2 and connected to the fixed unit 2. In a state where the movable unit 10 is connected to the fixed unit 2, the first coil 18 and the second coil 19 face each other with a predetermined gap in the axial direction X. Further, the first light emitting element 25A and the first light receiving element 25B are located on the axis L and face each other in the axis direction X. The second light receiving element 26B is located at a position that overlaps the movement locus when the circular movement locus in which the two second light emitting elements 26A move when the movable unit 10 rotates around the axis L is viewed from the axial direction X. Have been placed.

FIG. 8 is an explanatory diagram of the optical path of the first signal light S1 and the optical path of the second signal light S2. In FIG. 8, the first substrate 22, the first light emitting element 25A, the first light receiving element 25B, the second substrate 62, the second light emitting element 26A, the second light receiving element 26B, and the second holder 60 are taken out and shown. As shown in FIG. 8, the first signal light S1 emitted from the first light emitting element 25A passes through the columnar member 91 of the second holder 60 (columnar portion 11a of the first shaft portion 11) in the second direction X2. Then, it reaches the first light receiving element 25B.

On the other hand, the second signal light S2 emitted from the second light emitting element 26A passes through the holder body member 92 (cylindrical portion 12b of the first shaft portion 11) of the second holder 60 in the first direction X1 and is second. 2 Reach the light receiving element 26B. That is, since the two second light emitting elements 26A are separated from the axis L by a predetermined distance in the radial direction, when the movable unit 10 rotates around the axis L, each of the two second light emitting elements 26A is the second in the axis L direction. 2 Passes through a position facing the light receiving element 26B. Therefore, the second signal light S2 emitted from the second light emitting element 26A passes through the holder main body member 92 (cylindrical portion 12b of the first shaft portion 11) and reaches the second light receiving element 26B.

Here, if the first optical communication by the first signal light S1 is used, the rotation display unit can be driven and controlled from the fixed unit 2 side to the rotation display unit attached to the second shaft portion 12. Control signals can be transmitted. Further, by using the second optical communication by the second signal light S2, information such as the rotation speed of the movable unit 10 can be fed back from the movable unit 10 side to the fixed unit 2 side.

(Action effect)
According to this example, the first coil 18 is the first support of the first coil holding portion 37 in a state where the first fitting portion 41 of the first coil holding portion 37 of the first holder 21 is fitted in the center hole. It is supported by the surface 42a. Therefore, the first coil 18 is positioned on the first holder 21 with reference to the first fitting portion 41. Further, the first holder 21 is made immovable in the radial direction by the first fitting portion 41. Further, the first coil holding portion 37 includes a contact portion 49 that contacts the first coil 18 from the side opposite to the first support surface 42a. Therefore, the first coil 18 is positioned in the axial direction X by the first support surface 42a and the contact portion 49. Further, the first coil 18 is made immovable in the axial direction X by the first support surface 42a and the contact portion 49. Therefore, the first coil 18 can be fixed to the first holder 21 without using an adhesive.

Further, in this example, the first holder 21 is provided with a plurality of hooks 45 on the first annular portion 43 located on the outer peripheral side of the first support portion 42. Since the pillar portion 45a of each hook 45 is elastically deformable in the radial direction, it is easy to mount the first coil 18 on the first support surface 42a. Further, when the first coil 18 is placed on the first support surface 42a, the pillar portion 45a elastically returns to its original shape, and the claw portion 45b comes into contact with the side of the first coil 18 opposite to the first support surface 42a. It becomes the contact portion 49. Therefore, it is easy to sandwich the first coil 18 between the first support surface 42a and the contact portion 49.

Further, the first support portion 42 includes an urging portion 47 that urges the first coil 18 toward the side where the second coil 19 is located. Therefore, when the first coil 18 is supported by the first support surface 42a, the urging portion 47 urges the first coil 18 toward the side of the second coil 19. Therefore, it is possible to prevent the first coil 18 from rattling between the first support surface 42a and the contact portion 49. Further, since the first coil 18 is urged in the direction approaching the second coil 19 by the urging force of the urging portion 47, the first coil 18 is moved between the first support surface 42a and the abutting portion 49. It is possible to prevent the coil 19 from being arranged at a position away from the second coil 19. As a result, it is possible to prevent the gap between the first coil 18 and the second coil 19 from becoming large and the power transmission efficiency from being lowered.

Further, each hook 45 and each urging portion 47 are provided at different angular positions around the axis L. Therefore, when molding the resin-made first holder 21 having the plurality of hooks 45 and the plurality of urging portions 47, it becomes easy to mold the first holder 21 with high accuracy.

Further, in this example, the second coil 19 is the second support of the second coil holding portion 80 in a state where the second fitting portion 81 of the second coil holding portion 80 of the second holder 60 is fitted in the center hole. It is supported by the surface 82a. Therefore, the second coil 19 is positioned on the second holder 60 with reference to the second fitting portion 81. Further, the second holder 60 is made immovable in the radial direction by the second fitting portion 81. Further, the second holder 60 includes a plate member 61 that is fixed to the second coil holding portion 80 and comes into contact with the second coil 19 from the side opposite to the second support surface 82a. Therefore, the second coil 19 can be fixed to the second holder 60 by the second support surface 82a and the plate member 61 in a state of being immovable in the axial direction X.

Further, a plate member 61 which is fixed to the second fitting portion 81 of the second holder 60 and comes into contact with the second coil 19 from the side of the first coil 18 and the second coil of the first holder 21 to the first coil 18 The hook 45 that abuts from the side of 19 does not overlap when viewed from the axial direction X. Therefore, even if the contact portion 49 is located on the side of the second coil 19 of the first coil 18 and the plate member 61 is located on the side of the first coil 18 of the second coil 19, the first coil 18 and the first coil 18 are located. It is easy to bring the two coils 19 closer to each other in the axial direction X.

Further, in this example, the first annular magnetic shield sheet 52 and the second annular magnetic shield sheet 88 made of a magnetic material are provided, and the first annular magnetic shield sheet 52 is arranged on the opposite side of the first coil 18 from the second coil 19. The second annular magnetic shield sheet 88 is arranged on the side of the second coil 19 opposite to the first coil 18. Therefore, it is possible to suppress the magnetic coupling between the first coil 18 and the second coil 19 from being affected by the magnetic field from the outside in the axial direction X.

Further, in this example, the first tubular magnetic shield sheet 51 and the second tubular magnetic shield sheet 87 made of a magnetic material are provided. Therefore, it is possible to suppress the magnetic coupling between the first coil 18 and the second coil 19 from being affected by the magnetic field from the inner peripheral side. Therefore, it is possible to arrange the first metal ball bearing 13 on the inner peripheral side of the first coil 18.

1 ... Non-contact power transmission device, 2 ... Fixed unit, 3 ... Exterior cover, 5 ... Cylindrical part, 6 ... Circular plate part, 7 ... Cover side cylinder part, 10 ... Movable unit, 11 ... First shaft part, 11a ... Columnar portion, 11b ... Cylindrical portion, 12 ... 2nd shaft portion, 13 ... 1st ball bearing, 14 ... 2nd ball bearing, 18 ... 1st coil, 19 ... 2nd coil, 21 ... 1st holder, 22 ... 1st substrate, 22a ... Substrate surface of 1st substrate, 23 ... Opening, 25A ... 1st light emitting element, 25B ... 1st light receiving element, 26A ... 2nd light emitting element, 26B ... 2nd light receiving element, 28 ... Insulating sheet , 29 ... plate, 31 ... frame plate part, 32 ... large diameter cylinder part, 33 ... upper plate part, 34 ... annular plate part, 35 ... small diameter cylinder part, 37 ... first coil holding part, 41 ... first fitting Part, 42 ... 1st support part, 42a ... 1st support surface, 43 ... 1st annular part, 45 ... hook, 45a ... pillar part, 45b ... claw part, 47 ... urging part, 47a ... support part part, 47b ... Protrusion, 48 ... Slit, 48a ... First slit part, 48b ... Second slit part, 49 ... Contact part, 51 ... First tubular magnetic shield sheet, 52 ... First annular magnetic shield sheet, 60 ... Second holder , 61 ... Plate member, 62 ... Second substrate, 62a ... Substrate surface of second substrate, 63 ... Cover, 65 ... Opening, 68 ... Body, 69 ... Outer annular plate, 70 ... Cylinder, 71 ... Inside Annular plate portion, 75 ... Large diameter annular plate portion, 76 ... Medium diameter cylindrical portion, 77 ... Medium diameter annular plate portion, 80 ... Second coil holding portion, 81 ... Second fitting portion, 82 ... Second support portion, 82a ... 2nd support surface, 83 ... urging part, 83a ... support part, 83b ... protrusion, 84 ... slit, 84a ... first slit part, 84b ... second slit part, 87 ... second tubular magnetic shield sheet , 88 ... Second annular magnetic shield sheet, 91 ... Columnar member, 91a ... Pillar part, 91b ... Bending part, 92 ... Holder body member, 92a ... Center hole, S1 ... First signal light, S2 ... Second signal light, L ... Axis, X ... Axis direction, X1 ... 1st direction, X2 ... 2nd direction

Claims (7)

The first holder including the first coil, the second holder including the second coil coaxial with the first coil and facing the first coil with a gap, and the first holder and the second holder are described. In a non-contact power transmission device having a connection mechanism for connecting the first coil and the axis of the second coil so as to be relatively rotatable around the axis, and transmitting power between the first coil and the second coil. ,
The first holder includes a first coil holding portion for holding the first coil.
The first coil holding portion includes a first fitting portion that fits into the center hole of the first coil, and the first coil on the outer peripheral side of the first fitting portion from a side opposite to the second coil. A first support portion having an annular first support surface to be supported, and an abutting portion that comes into contact with a part of the first coil supported by the first support surface in the circumferential direction from the side of the second coil. A non-contact power transmission device characterized by being provided. The first holder is made of resin and is made of resin.
The first coil holding portion includes a first annular portion located on the outer peripheral side of the first support portion.
The first annular portion is provided with hooks at a plurality of locations separated in the circumferential direction.
Each hook includes a pillar portion that inclines toward the inner peripheral side from the first annular portion toward the side of the second coil, and a claw portion that protrudes from the end of the pillar portion on the side of the second coil to the inner peripheral side. ,
The claw portion overlaps with the first support surface when viewed from the axial direction.
The pillar portion can be elastically deformed in a direction intersecting the axis line.
The non-contact power transmission device according to claim 1, wherein the claw portion is the contact portion. The first support portion includes urging portions for urging the first coil toward the side where the second coil is located at a plurality of locations in the circumferential direction of the first support portion.
Each urging portion is divided into a tongue piece-shaped portion by a slit penetrating the first support portion in the axial direction, and is provided on the support portion portion and projects to the side where the second coil is located. With a protrusion and
The non-contact power transmission device according to claim 2, wherein the support portion portion is elastically deformable in the axial direction. The non-contact power transmission device according to claim 3, wherein each hook and each urging portion are provided at different angle positions about the axis. It has an annular plate member fixed to the second holder, and has an annular plate member.
The second holder is provided with a second coil holding portion at a position overlapping the first coil holding portion when viewed from the axial direction.
The second coil holding portion includes a second fitting portion that fits into the central hole of the second coil, and the second coil on the outer peripheral side of the second fitting portion from a side opposite to the first coil. A second support portion having an annular second support surface to support, and
The plate member is fixed to the second fitting portion and abuts on the opening edge of the central hole in the second coil from the side of the second coil.
The non-contact power transmission device according to claim 3 or 4, wherein the plate member and the hook do not overlap when viewed from the axial direction. A first annular magnetic shield sheet and a second annular magnetic shield sheet made of a magnetic material are provided.
The first annular magnetic shield sheet is interposed between the first support surface and the first coil.
The non-contact power transmission device according to claim 5, wherein the second annular magnetic shield sheet is interposed between the second support surface and the second coil. It has a first tubular magnetic shield sheet and a second tubular magnetic shield sheet made of magnetic material.
The second holder includes a shaft portion extending in the axial direction from the inside of the second coil toward the side of the first coil.
The connection mechanism includes an annular bearing that is held on the inner peripheral side of the first coil in the first holder and supports the shaft portion from the outer peripheral side.
The second fitting portion is provided integrally with the shaft portion, and is provided.
The first fitting portion has a tubular shape and has a tubular shape.
The bearing is held inside the first fitting portion and is held.
The first tubular magnetic shield sheet is interposed between the first fitting portion and the first coil.
The non-contact power transmission device according to claim 5 or 6, wherein the second tubular magnetic shield sheet is interposed between the second fitting portion and the second coil.

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