Power generation device

A power generation device includes a first magnetic body including a side surface that makes contact with or separates from the first side surface of the yoke, a second magnetic body including a side surface that makes contact with or separates from the second side surface of the yoke, and a magnet including a first magnetic pole face and a second magnetic pole face that has a magnetic pole different from a magnetic pole of the first magnetic pole face. The first magnetic pole face is attracted to the attraction surface of the first magnetic body, the second magnetic pole face is attracted to the attraction surface of the second magnetic body, and at least one of the first magnetic body and the second magnetic body rotates in a state of being attracted to the magnet.

RELATED APPLICATIONS

This application is the U.S. National Phase under 35 U.S.C. § 371 of International. Application No. PCT/JP2016/000754, filed on Feb. 15, 2016, which in turn claims the benefit of Japanese Application No. 2015-046355, filed on Mar. 9, 2015, the disclosures of which are incorporated by reference herein.

TECHNICAL FIELD

The present disclosure relates to a power generation device used in various electronic devices, devices for remotely manipulating the electronic devices, and manipulation units.

BACKGROUND ART

In recent years, development of a small-sized power generation device has been desired for various electronic devices, devices for remotely manipulating the electronic devices, and manipulation units.

A conventional power generation device will now be described with reference toFIGS. 11 to 14.

FIG. 11is an external perspective view of conventional power generation device100,FIG. 12is a top view of conventional power generation device100with upper case2removed,FIG. 13illustrates a first state of magnetic circuit101of conventional power generation device100, andFIG. 14illustrates a second state of magnetic circuit101of conventional power generation device100.

Conventional power generation device100includes magnetic circuit101(seeFIGS. 13 and 14). Housing102illustrated inFIG. 11has a box-shape which is formed of assembled resin lower case1and resin upper case2. Knob3for manipulation projects from a side surface of housing102. As illustrated inFIG. 12, magnetic circuit101is accommodated in housing102. By sliding knob3in the right-and-left direction, the state of magnetic circuit101housed in power generation device100transitions to either the first state illustrated inFIG. 13or the second state illustrated inFIG. 14.

As illustrated inFIGS. 13 and 14, magnetic circuit101includes bar-shaped central yoke6, bar-shaped magnetic member10, and bar-shaped magnetic member15. Coil5is wound around bar-shaped central yoke6. Magnetic member10and magnetic member15are disposed such that their magnetic poles are opposite to each other. Central yoke6is disposed between magnetic member10and magnetic member15.

Magnetic member10is formed of magnet11, square-column magnetic body12, and square-column magnetic body13. Magnetic body12is bonded to the front surface of magnet11, and magnetic body13is bonded to rear surface of magnet11. Magnet11is disposed such that a side on the magnetic body12side (front side) is an S-pole and a side on the magnetic body13side (rear side) is an N-pole. Magnetic member15is configured in a manner similar to magnetic member10. However, magnet16is disposed such that a side on the magnetic body17side (front side) is an N-pole and a side on the magnetic body18side (rear side) is an S-pole.

Central yoke6, magnetic member10, and magnetic member15are disposed between auxiliary yoke7and auxiliary yoke8.

As illustrated inFIG. 12, central yoke6, auxiliary yoke7, and auxiliary yoke8are fixed in housing102and restricted to move in the right-and-left direction. Magnetic member10and magnetic member15are fixed to drive member4.

Drive member4is supported so as to be movable in the right-and-left direction in housing102. Drive member4is connected to knob3and moves in the right-and-left direction by sliding knob3. By moving magnetic member10and magnetic member15which are supported by drive member4in the right-and-left direction, the state of magnetic circuit101transitions to either the first state (illustrated inFIG. 13) or the second state (illustrated inFIG. 14).

In the first state, magnetic member15is in contact with central yoke6as illustrated inFIG. 13. In the first state, a magnetic flux flows through central yoke6in a direction indicated by arrow A (from the front side to the rear side).

Meanwhile, in the second state, magnetic member10is in contact with central yoke6as illustrated inFIG. 14. In the second state, a magnetic flux flows through central yoke6in a direction indicated by arrow B (from the rear side to the front side).

The state of magnetic circuit101changes from the first state to the second state by sliding knob3for manipulation. By this change in the state, the direction of the magnetic flux that flows through central yoke6is reversed. This change in the magnetic flux generates an electromotive force in coil5. That is, power generation device100generates power by causing the state of magnetic circuit101to transition from the first state to the second state.

For example, PTL 1 is known as prior art literature information related to this application.

CITATION LIST

Patent Literature

SUMMARY OF THE INVENTION

A power generation device of the present disclosure includes a yoke around which a coil is wound, and the yoke has a first side surface located on a first direction side with respect to the coil and a second side surface located on a second direction side with respect to the coil. The second direction is opposite the first direction. Furthermore, the power generation device includes a first magnetic body including a side surface that makes contact with or separates from the first side surface of the yoke, a second magnetic body including a side surface that makes contact with or separates from the second side surface of the yoke, and a magnet including a first magnetic pole face and a second magnetic pole face that has a magnetic pole different from a magnetic pole of the first magnetic pole face. The first magnetic pole face of the magnet is attracted to an attraction surface of the first magnetic body, the second magnetic pole face of the magnet is attracted to an attraction surface of the second magnetic body, and at least one of the first magnetic body and the second magnetic body rotates in a state of being attracted to the magnet.

DESCRIPTION OF EMBODIMENTS

Prior to description of the present exemplary embodiment, a conventional power generation device will now be described.

Conventional power generation device100, which has been described with reference toFIGS. 11 to 14, includes magnetic circuit101that changes a direction of a magnetic flux flowing through central yoke6. Magnetic circuit101produces an electromotive force by Faraday's law. The power generation device is thus desired to generate stable power with small fluctuation.

Power generation device200of the present disclosure can provide stable power generation since the fluctuation of change in the magnetic flux flowing through a yoke disposed in a center is small.

The present exemplary embodiment will now be described with reference toFIGS. 1 to 10.

Exemplary Embodiment

FIG. 1is an external perspective view of power generation device200according to an exemplary embodiment,FIG. 2is a top view of power generation device200according to the exemplary embodiment with upper case22removed,FIG. 3illustrates a first state of magnetic circuit201, andFIG. 4illustrates a second state of magnetic circuit201.

As illustrated inFIG. 2, magnetic member30includes magnet31, magnetic body32, and magnetic body33. Magnet31has a form of a rectangular solid and is disposed with an S-pole in a front surface and an N-pole in a rear surface. Magnetic body32having an L-shape in a top view is attracted to the front surface of magnet31, and magnetic body33having an L-shape in a top view is attracted to the rear surface of magnet31. Each of magnetic body32and magnetic body33is rotatable with respect to magnet31. Although the present exemplary embodiment has rotatable magnetic body32and rotatable magnetic body33, it is not required that both the magnetic body32and magnetic body33are rotatable.

As illustrated inFIGS. 3 and 4, the state of magnetic member30transitions to either a state being separated from central yoke50(hereinafter referred to as “a first state”) or a state in contact with central yoke50(hereinafter referred to as “a second state”). Transition in the state changes the magnetic flux flowing through central yoke50and thereby generates an electromotive force in coil25.

With magnetic body32and magnetic body33being supported in a manner rotatable with respect to magnet31, magnetic member30corrects, along the rotating direction, positions of a contact surface of magnetic body32(side surface32B) and a contact surface of magnetic body33(side surface33B) which make contact with central yoke50. Thus, a gap is hardly generated between magnetic body32and central yoke50as well as between magnetic body33and central yoke50. That is, in power generation device200, a gap is hardly generated between magnetic member30and central yoke50.

A detailed configuration and an operation of power generation device200will now be described.

<Configuration of Power Generation Device200>

As illustrated inFIGS. 1 and 2, housing202has a form of a box and is formed of assembled resin lower case21and resin upper case22. Housing202includes therein magnetic circuit201.

As illustrated inFIG. 2, knob23projecting from a side surface of housing202is connected to drive member24supporting magnetic member30and magnetic member40. By sliding knob23in the right-and-left direction, the state of magnetic circuit201can be caused to transition to either the first state illustrated inFIG. 3or the second state illustrated inFIG. 4.

In the following description, a direction along the longitudinal direction of central yoke50is defined as the front-and-rear direction and a direction perpendicular to the front-and-rear direction in a top view is defined as the right-and-left direction.

Central yoke50is a bar-shaped magnetic body extending in the front-and-rear direction. Coil25is wound around central yoke50. Magnetic member30and magnetic member40each have a U-shape in a top view. Central yoke50is disposed between magnetic member30and magnetic member40.

A front surface of rectangular-solid-shaped magnet31(magnetic pole face31A) attracts magnetic body32. Similarly, the rear surface of magnet31(magnetic pole face31B) attracts magnetic body33. Magnet31is disposed such that magnetic pole face31A is the S-pole and magnetic pole face31B is the N-pole.

The front surface of rectangular-solid-shaped magnet41(magnetic pole face41A) attracts magnetic body42. Similarly, the rear surface of magnet41(magnetic pole face41B) attracts magnetic body43. Magnet41is disposed such that magnetic pole face41A is the N-pole and magnetic pole face41B is the S-pole.

In auxiliary yoke61and auxiliary yoke62, surfaces opposed to each other are respectively defined as plane61A and plane62A. That is, plane61A of auxiliary yoke61is opposed to magnetic member30, while plane62A of auxiliary yoke62is opposed to magnetic member40.

As illustrated inFIG. 2, central yoke50, auxiliary yoke61, and auxiliary yoke62are fixed in housing202. Drive member24is supported so as to be movable in the right-and-left direction in housing202. Drive member24is illustrated with hatching inFIG. 2. Magnetic member30and magnetic member40are supported by drive member24. That is, magnetic member30and magnetic member40move in the right-and-left direction in conjunction with movement of drive member24in the right-and-left direction. By this movement, the state of magnetic circuit201transitions to either the first state illustrated inFIG. 3or the second state illustrated inFIG. 4.

In the first state, as illustrated inFIG. 3, magnetic member30and magnetic member40are located on the right side. In the first state, magnetic member30and central yoke50are separated from each other and magnetic member40and central yoke50are in contact with each other. Magnetic member30and auxiliary yoke61are in contact with each other and magnetic member40and auxiliary yoke62are separated from each other.

That is, in the first state, a magnetic flux of magnet41of magnetic member40flows through central yoke50. The magnetic flux thus flows through central yoke50from the front side to the rear side as indicated by arrow A inFIG. 3. In the first state, since magnetic member30and auxiliary yoke61are in contact with each other, a magnetic flux of magnet31flows through auxiliary yoke61. Therefore, the magnetic flux of magnet31does not have much effect on the magnetic flux flowing through central yoke50.

In the second state, as illustrated inFIG. 4, magnetic member30and magnetic member40are located on the left side. In the second state, magnetic member30and central yoke50are in contact with each other and magnetic member40and central yoke50are separated from each other. Magnetic member30and auxiliary yoke61are separated from each other and magnetic member40and auxiliary yoke62are in contact with each other.

That is, in the second state, the magnetic flux of magnet31of magnetic member30flows through central yoke50. The magnetic flux thus flows through central yoke50from the rear side to the front side as indicated by arrow B inFIG. 4. In the second state, since magnetic member40and auxiliary yoke62are in contact with each other, the magnetic flux of the magnet41flows through auxiliary yoke62. Therefore, the magnetic flux of the magnet41does not have much effect on the magnetic flux flowing through central yoke50.

By changing the state of magnetic circuit201from the first state to the second state, for example, by sliding knob23, the direction of the magnetic flux flowing through the central yoke50is reversed. This change in the magnetic flux generates an electromotive force in coil25.

That is, power generation device200generates power by causing the state of magnetic circuit201to transition from the first state to the second state. Power generation device200also generates power in a similar manner by causing the state to transition from the second state to the first state.

Central yoke50includes front portion51having a form of a square-column and located on the front side with respect to coil25, and rear portion52having a form of a square-column and located on the rear side with respect to coil25. A right side surface of front portion51is defined as side surface51A, and a left side surface of front portion51is defined as side surface51B. Side surface51A and side surface51B are facing opposite sides. A right side surface of rear portion52is defined as side surface52A, and a left side surface of rear portion52is defined as side surface52B. Side surface52A and side surface52B are facing opposite sides. Side surfaces51A,52A,51B, and52B are planar.

Auxiliary yoke61and auxiliary yoke62are rectangular-solid-shaped magnetic bodies extending in the front-and-rear direction. A left surface of auxiliary yoke61is defined as plane61A. A right surface of auxiliary yoke62is defined as plane62A. That is, plane61A of auxiliary yoke61is opposed to magnetic member30. Plane62A of auxiliary yoke62is opposed to magnetic member40. Each of plane61A and plane62A is planar.

Magnetic member30includes magnet31, magnetic body32, and magnetic body33. Magnet31has a form of a rectangular solid. A surface on the front side which is the S-pole is defined as magnetic pole face31A, and a surface on the rear side which is the N-pole is defined as magnetic pole face31B.

Magnetic body32and magnetic body33are L-shaped magnetic bodies. One of distal ends of magnetic body32and one of distal ends of magnetic body33are attracted to magnet31. The other distal end of magnetic body32and the other distal end of magnetic body33are opposed to central yoke50. The dimensions in the up-and-down direction (thickness) of magnetic body32and magnetic body33are as large as that of magnet31.

A surface of magnetic body32attracted to magnetic pole face31A of magnet31is defined as attraction surface32A. A surface of magnetic body32opposed to side surface51A of central yoke50is defined as side surface32B. A surface of magnetic body32opposed to plane61A of auxiliary yoke61is defined as opposing surface32C. Side surface32B and opposing surface32C are planar.

A surface of magnetic body33attracted to magnetic pole face31B of magnet31is defined as attraction surface33A. A surface of magnetic body33opposed to side surface52A of central yoke50is defined as side surface33B. A surface of magnetic body33opposed to plane61A of auxiliary yoke61is defined as opposing surface33C. Side surface33B and opposing surface33C are planar.

Magnetic member40includes magnet41, magnetic body42, and magnetic body43. Magnet41has a form of a rectangular solid. A surface on the front side having the N-pole is defined as magnetic pole face41A, and a surface on the rear side having the S-pole is defined as magnetic pole face41B. Desirably, magnet31and magnet41have a same configuration to reduce a number of types of components.

Magnetic body42and magnetic body43are L-shaped magnetic bodies. One of distal ends of magnetic body42and one of distal ends of magnetic body43are attracted to magnet41. The other distal end of magnetic body42and the other distal end of magnetic body43are opposed to central yoke50. The dimensions in the up-and-down direction (thickness) of magnetic body42and magnetic body43are as large as that of magnet41. Desirably, magnetic bodies32,33,42, and43have a same configuration to reduce a number of types of components.

A surface of magnetic body42attracted to magnetic pole face41A of magnet41is defined as attraction surface42A. A surface of magnetic body42opposed to side surface51B of central yoke50is defined as side surface42B. A surface of magnetic body42opposed to plane62A of auxiliary yoke62is defined as opposing surface42C. Side surface42B and opposing surface42C are planar.

Similarly, a surface of magnetic body43attracted to magnetic pole face41B of magnet41is defined as attraction surface43A. A surface of magnetic body43opposed to side surface52B of central yoke50is defined as side surface43B. A surface of magnetic body43opposed to plane62A of auxiliary yoke62is defined as opposing surface43C. Side surface43B and opposing surface43C are planar.

[First State and Second State]

In the first state, magnetic member30and magnetic member40are located on the right side as illustrated inFIG. 3, and opposing surface32C and opposing surface33C of magnetic member30are in contact with plane61A of auxiliary yoke61. Meanwhile, side surface32B is separated from side surface51A of central yoke50and side surface33B is separated from side surface52A of central yoke50.

Opposing surface42C and opposing surface43C of magnetic member40are separated from plane62A of auxiliary yoke62. Side surface42B is in contact with side surface51B of central yoke50and side surface43B is in contact with side surface52B of central yoke50.

In the second state, magnetic member30and magnetic member40are located on the left side as illustrated inFIG. 4, and opposing surface32C and opposing surface33C of magnetic member30are separated from plane61A of auxiliary yoke61. Meanwhile, side surface32B is in contact with side surface51A of central yoke50. Side surface33B is in contact with side surface52A of central yoke50.

Opposing surface42C and opposing surface43C of magnetic member40are in contact with plane62A of auxiliary yoke62. Side surface42B is separated from side surface51B of central yoke50. Side surface43B is separated from side surface52B of central yoke50.

Preferably, as illustrated inFIGS. 5 and 6, attraction surfaces32A and33A of magnetic members30and40each have an are shape that slightly protrudes toward magnet31in a top view. Preferably, in a similar manner, attraction surfaces42A and43A each have an arc shape that slightly protrudes toward magnet41in a top view. Magnetic body32and magnetic body33are preferably rotatable with respect to magnet31. Magnetic body42and magnetic body43are preferably rotatable with respect to magnet41. This will be described below in detail.

FIG. 5is a partially enlarged view of magnetic member30. Attraction surface32A of magnetic body32has an arc shape slightly protruding to the rear side in a top view. Attraction surface33A has an are shape slightly protruding to the front side in a top view.

The arc is illustrated to protrude larger than it really is for convenience of explanation.

Magnetic body32and magnetic body33are supported by drive member24(seeFIG. 2) so as to be rotatable with respect to magnet31. More specifically, magnetic body32is rotatable about a contact point between attraction surface32A and magnetic pole face31A in a state of being attracted to magnet31. Magnetic body33is rotatable about a contact point between attraction surface33A and magnetic pole face31B in a state of being attracted to magnet31.

FIG. 6is a partially enlarged view of magnetic member40. Attraction surface42A of magnetic body42has an arc shape slightly protruding to the rear side in a top view. Attraction surface43A has an are shape slightly protruding to the front side in a top view. The arc is illustrated to protrude larger than it really is for convenience of explanation.

Magnetic body42and magnetic body43are supported by drive member24(seeFIG. 2) so as to be rotatable with respect to magnet41. More specifically, magnetic body42is rotatable about a contact point between attraction surface42A and magnetic pole face41A in a state of being attracted to magnet41. Magnetic body43is rotatable about a contact point between attraction surface43A and magnetic pole face41B in a state of being attracted to magnet41.

Attraction surfaces32A,33A,42A, and43A need not have an arc shape. Each of attraction surfaces32A and33A may have any curved shape that protrudes toward magnet31in a top view. Similarly, each of attraction surfaces42A and43A may have any curved shape that protrudes toward magnet41in a top view.

At least one of attraction surface32A of magnetic body32and attraction surface33A of magnetic body33is required to have a curved shape.

Power generation device200according to the present exemplary embodiment is configured as described above. In power generation device200thus configured, a gap is hardly generated between central yoke50and magnetic member30. A gap is also hardly generated between central yoke50and magnetic member40.

[Description on Operation of Magnetic Members30and40]

With reference toFIGS. 7 and 8, a reason why a gap is hardly generated between central yoke50and magnetic member30will now be described.FIGS. 7 and 8are views for describing operations of magnetic bodies32and33of magnetic member30.FIG. 7corresponds to the first state andFIG. 8corresponds to the second state. In the present exemplary embodiment, description is made assuming a case where side surface32B of magnetic body32is processed to be inclined with respect to opposing surface32C as illustrated inFIGS. 7 and 8. Moreover, description is made assuming a case where side surface33B of magnetic body33is processed to be inclined with respect to opposing surface33C.

Dashed lines inFIGS. 7 and 8show shapes of magnetic body32and magnetic body33which are finished as designed. As illustrated inFIGS. 7 and 8, side surface32B of magnetic body32is inclined with respect to the designed shape. Opposing surface33C of magnetic body33is inclined with respect to the designed shape. For convenience of explanation, the inclination of each of side surface32B and opposing surface33C is illustrated larger than it really is inFIGS. 7 and 8.

As illustrated inFIG. 7, in the first state, magnetic member30is in contact with auxiliary yoke61. Since opposing surface32C of magnetic body32and plane61A of auxiliary yoke61are planar, opposing surface32C and plane61A are in contact with each other without any gap. In other words, opposing surface32C and plane61A are parallel to each other. In this state, side surface32B of magnetic body32is not parallel to side surface51A of central yoke50.

Magnetic body33, which is rotatably supported with respect to magnet31, is inclined to allow opposing surface33C to be parallel to plane61A and to make contact with plane61A without any gap.

Now, drive member24(seeFIG. 2) is moved to the left to cause the state of magnetic circuit201to transition from the first state to the second state illustrated inFIG. 8. Magnetic body32and magnetic body33are rotatably supported with respect to magnet31. Thus, magnetic body32can rotate to allow side surface32B to be parallel to side surface51A of central yoke50. Similarly, magnetic body33can rotate to allow side surface33B to be parallel to side surface51A.

In the second state, as illustrated inFIG. 8, magnetic body32rotates to allow side surface32B to be parallel to side surface51A and to make contact with side surface51A without any gap. Similarly, magnetic body33rotates to allow side surface33B to be parallel to side surface52A and to make contact with side surface52A without any gap.

In this state, opposing surface32C is not parallel to plane61A of auxiliary yoke61. Opposing surface33C is also not parallel to plane61A of auxiliary yoke61.

When drive member24(seeFIG. 2) is moved to the right to cause the state of magnetic circuit201to transition from the second state again to the first state, magnetic body32and magnetic body33also rotate with respect to magnet31. As illustrated inFIG. 7, each of opposing surface32C of magnetic body32and opposing surface33C of magnetic body33makes contact with plane61A of auxiliary yoke61without any gap. Auxiliary yoke61is disposed so as to be opposed to magnetic body32and magnetic body33.

Magnetic body32has opposing surface32C that is opposed to auxiliary yoke61, and magnetic body33has opposing surface33C that is opposed to auxiliary yoke61.

SUMMARY

As described above, in power generation device200according to the present exemplary embodiment, magnetic body32and magnetic body33can rotate to correct, along the rotating direction, the position of surfaces that make contact with central yoke50. That is, in power generation device200, a gap is hardly generated between magnetic member30and central yoke50. Thus, power generation device200can increase the density of the magnetic flux flowing through central yoke50, thereby keeping fluctuation of change in the magnetic flux during power generation small to provide stable power generation.

As described above, each of attraction surface32A of magnetic body32and attraction surface33A of magnetic body33is required to have an arc shape slightly protruding toward magnet31in a top view. With each attraction surface has an arc shape, as illustrated inFIGS. 7 and 8, either in the first state or the second state, the gap between attraction surface32A and magnetic pole face31A does not greatly change and the gap between attraction surface33A and magnetic pole face31B does not greatly change. The magnetic flux of magnet31is therefore efficiently and stably introduced into magnetic body32and magnetic body33. That is, power generation device200according to the present exemplary embodiment is capable of reducing leakage of magnetic flux in the magnetic circuit (magnetic circuit201), thereby keeping fluctuation of change in the magnetic flux during power generation small to provide stable power generation.

The operation in the case where side surface32B and opposing surface32C of magnetic body32are not parallel is described above. However, a technical idea of the present disclosure is not limited to the above description.

For example, the technical idea of the present disclosure is applicable to power generation device200in which central yoke50and auxiliary yoke61are disposed so as to be inclined with respect to magnetic member30due to assembly tolerances. Furthermore, the technical idea is applicable to a case where a contact surface (side surface51A or side surface52A) of central yoke50that makes contact with magnetic member30is processed to be inclined with respect the designed shape. The technical idea is also applicable to a case where plane61A of auxiliary yoke61is processed to be inclined with respect the designed shape.

In such cases as well, in power generation device200, magnetic body32and magnetic body33rotate with respect to magnet31. Rotation of magnetic body32and magnetic body33corrects, along the rotating direction, a position of a contact surface (side surface32B or side surface33B) to central yoke50disposed with inclination. Thus, a gap is hardly generated between magnetic member30and central yoke50.

The same is applied to auxiliary yoke61. Rotation of magnetic body32and magnetic body33corrects, along the rotating direction, a position of a contact surface (opposing surface32C or opposing surface33C). Thus, a gap is hardly generated between magnetic member30and auxiliary yoke61.

It is not always required that both the magnetic body32and magnetic body33are rotatable with respect to magnet31. Only one of magnetic body32and magnetic body33may be rotatable with respect to magnet31. In such a case, for example, attraction surface33A of magnetic body33and magnetic pole face31B of magnet31may be disposed parallel to each other and may be fixed to each other by adhesives. Magnetic body33may be supported by drive member24to integrally rotate with magnet31. In this configuration, magnetic body33and magnet31integrally rotate to correct the position of the contact surface (side surface32B and side surface33B) of magnetic member30that makes contact with central yoke50.

Although magnetic member30makes contact with central yoke50in the configuration described above, the technical idea of the present disclosure includes, for example, a state in which side surface32B and side surface51A are parallel and in close proximity to each other. Similarly, the technical idea of the present disclosure includes a state in which side surface33B and side surface52A are parallel and in close proximity to each other.

Although magnetic member30makes contact with auxiliary yoke61in the configuration described above, magnetic member30is not always required to make contact with auxiliary yoke61. That is, power generation device200may have any configuration in which magnetic member30and auxiliary yoke61are attracted to each other and are in close proximity to each other. For example, the right-and-left movement of drive member24(seeFIG. 2) may be restricted by, for example, lower case21to generate a slight gap between opposing surface32C and plane61A or between opposing surface33C and plane61A. That is, magnetic members30(opposing surface32C and opposing surface33C) may not make contact with auxiliary yoke61but may be in close proximity to auxiliary yoke61. Such a configuration provides a collateral effect of reducing collision sounds generated by magnetic member30contacting auxiliary yoke61.

Magnetic member40is configured in a similar manner as described above, and therefore illustration and detailed description are omitted. In this case, magnetic body42and magnetic body43rotate with respect to magnet41. This rotation allows side surface42B of magnetic member40to make contact with side surface51B of central yoke50without any gap and side surface43B of magnetic member40to make contact with side surface52B of central yoke50without any gap in the first state.

In the second state, each of opposing surfaces42C and43C of magnetic member40makes contact with plane62A of auxiliary yoke62without any gap.

If a film or the like is formed on a surface of a magnetic body or a magnet, the film or the like may be defined as a portion of the magnetic body or the magnet, or the film may be defined as a member different from the magnetic body or the magnet.

Modification of Exemplary Embodiment

An exemplary modification of the magnetic body of the disclosure will now be described with reference toFIGS. 9 and 10.FIG. 9illustrates a first state of magnetic circuit301, which is a modification of the exemplary embodiment according to the present disclosure.FIG. 10illustrates a second state of magnetic circuit301, which is the modification of the exemplary embodiment according to the present disclosure.

Power generation device200described with reference toFIGS. 1 to 8includes magnetic member30disposed on the right side of central yoke50and magnetic member40disposed on the left side of central yoke50.

However, it is not always necessary to provide two magnetic members30and40. As illustrated inFIGS. 9 and 10, magnetic member40may not be provided and only magnetic member30may be provided. That is, only one magnetic member (for example, magnetic member30) may be provided in one of the sides of central yoke50. For the modification illustrated inFIGS. 9 and 10, the component same as the exemplary embodiment is denoted with the same reference mark and detailed description thereof is omitted.

A flow of a magnetic flux of magnetic circuit301of the modification illustrated inFIGS. 9 and 10will now briefly be described.

In the first state, magnetic member30is not in contact with central yoke50as illustrated inFIG. 9. Thus, in the first state, an influence of magnetic member30on central yoke50is small, and therefore density of a magnetic flux flowing through central yoke50in a direction indicated by arrow B as illustrated inFIG. 9is very small.

In the second state, magnetic member30is attracted to central yoke50as illustrated inFIG. 10. That is, magnetic member30is in contact with central yoke50. In the second state, the density of the magnetic flux flowing through central yoke50in the direction indicated by arrow B inFIG. 10is larger than that of the first state. In this manner, the density of magnetic flux flowing through central yoke50changes by the transition from the first state to the second state. This generates an electromotive force in coil25.

As can be understood from the above, the power generation device according to the present disclosure does not always require two magnetic members30and40. The technical idea of the present disclosure is applicable to a configuration having one magnetic member30.

Terms for indicating directions, such as “up”, “down”, “front”, “rear”, “left”, and “right”, are used in the present exemplary embodiment merely by means of indicating relative positional relationship, not by way of limitations.

That is, power generation device200according to the present disclosure includes central yoke50around which coil25is wound, central yoke50having side surface51A located on the front side with respect to coil25and side surface52A located on the rear side with respect to coil25. Furthermore, power generation device200according to the present disclosure includes magnetic body32including side surface32B that makes contact with or separates from side surface51A of central yoke50, magnetic body33including side surface33B that makes contact with or separates from side surface52A of central yoke50, and a magnet including magnetic pole face31A and magnetic pole face31B that has a magnetic pole (N-pole) different from a magnetic pole (S-pole) of magnetic pole face31A.

Magnetic pole face31A of magnet31is attracted to attraction surface32A of magnetic body32, and magnetic pole face31B of magnet31is attracted to attraction surface33A of magnetic body33. At least one of magnetic body32and magnetic body33rotates in a state of being attracted to magnet31.

INDUSTRIAL APPLICABILITY

A power generation device according to the present disclosure provides stable power generation with small fluctuation.

The power generation device according to the present disclosure is applicable to electronic devices.

REFERENCE MARKS IN THE DRAWINGS