JP2012205451A - Vibration power generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic induction-type vibration power generator in which a magnetic flux of a permanent magnet can be prevented from adversely affecting the inside and outside of the vibration power generator.SOLUTION: A vibration power generator comprises: a cylindrical member; a coil unit made of a nonmagnetic and conductive material which is provided to be movable inside the cylindrical member along the longitudinal direction of the cylindrical member; a first permanent magnet which is fixed in a movable region of the coil unit and is magnetized along the longitudinal direction; and a second permanent magnet which is shorter than the first permanent magnet in the longitudinal direction and is arranged such that its magnetic pole on the side facing the first permanent magnet has the same polarity as that of the first permanent magnet.

Description

  The present invention relates to a vibration generator that generates power by moving a coil and crossing the magnetic flux of a fixed magnet.

  Conventionally, a vibration generator in which a permanent magnet is fixedly housed inside a cylindrical case and a coil is slidably provided along the permanent magnet is known from Patent Document 1 and the like. When the coil slides, the magnetic flux of the permanent magnet crosses the coil, and electric power is generated. FIG. 2 of Patent Document 1 describes a plurality of permanent magnets arranged in the longitudinal direction inside a cylindrical casing, and a coil fixed to a spring (spring) via a coil mounting portion. When this coil slides along a plurality of permanent magnets, the magnetic flux of the permanent magnets traverses the coils and power is generated.

JP 2007-195364 A

  Generally, in a vibration generator provided with a permanent magnet, the electromotive voltage is proportional to the magnetic flux density of the permanent magnet. For this reason, a permanent magnet having a high magnetic force is often provided in a vibration power generator. However, in the vibration generator described in Patent Document 1, it is considered that the magnetic flux generated from the permanent magnet adversely affects the inside and outside of the vibration generator. Specifically, adverse effects include malfunctions of electrical circuits provided in the vibration generator, malfunctions of peripheral devices such as medical devices such as cardiac pacemakers, and the like. For this reason, there was a problem that it was difficult to equip a vibration generator with a magnet with high magnetic force.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a vibration generator in which the magnetic flux of a permanent magnet is suppressed from adversely affecting the inside and outside of the vibration generator. To do.

  In order to achieve this object, the vibration generator according to claim 1 is provided with a cylindrical member and a nonmagnetic material provided inside the cylindrical member so as to be movable along a longitudinal direction of the cylindrical member. And a coil unit made of a conductive material, a first permanent magnet fixed in a possible area of the coil unit and magnetized along the longitudinal direction, and a length of the first permanent magnet in the longitudinal direction. And a second permanent magnet having a short length and facing the same pole as the first permanent magnet.

  In order to achieve this object, the vibration generator according to claim 2 is the vibration generator according to claim 1, wherein the length of the second permanent magnet in the longitudinal direction is the first permanent magnet. The cross-sectional radius is 70% or less.

  In order to achieve this object, the vibration generator according to claim 3 is the vibration generator according to claim 1 or 2, wherein one end of the coil unit is fixed inside the cylindrical member, The other end is movably held in the movable region by an elastic member connected to the coil unit, and the elastic member is from the same-polar facing surface of the first permanent magnet and the second permanent magnet. It is arranged on the second permanent magnet side.

  According to the vibration generator according to claim 1, in the longitudinal direction of the cylindrical member, the second permanent magnet is shorter than the length of the first permanent magnet, and the same pole as the first permanent magnet is arranged opposite to the first permanent magnet. . With this arrangement, it is possible to reduce the leakage magnetic field of the second permanent magnet on the side opposite to the side facing the first permanent magnet. By reducing this leakage magnetic field, the magnetic flux of the first permanent magnet is suppressed from adversely affecting the inside and outside of the vibration generator. An induced electromotive force can be generated.

  In the vibration generator according to claim 2, in addition to the effect of the invention according to claim 1, the length of the second permanent magnet in the longitudinal direction of the cylindrical member is 70% of the cross-sectional radius of the first permanent magnet. It is the following length. Thereby, the leakage magnetic field of the 2nd permanent magnet on the opposite side to the side which opposes the 1st permanent magnet can be reduced.

  In the vibration generator according to claim 3, in addition to the effect of the invention according to claim 1 or 2, the elastic member having one end fixed to the cylindrical member and the other end connected to the coil unit is the first. It arrange | positions from the same pole opposing surface of a permanent magnet and a 2nd permanent magnet to the 2nd permanent magnet side. With this arrangement, the elastic member is not easily affected by the magnetic field, and thus stable operation is possible. In addition, since a soft magnetic material can be used for the elastic member, the material selection range can be expanded.

It is a section schematic diagram showing composition of a vibration power generator in this embodiment. It is explanatory drawing which shows the dimension of a 1st permanent magnet and a 2nd permanent magnet. It is a cross-sectional schematic diagram which shows the structure of the vibration generator 200 used as the comparative example of this embodiment. It is a figure which shows the result of the magnetic field analysis of the vibration generator 1. It is a figure which shows the result of the magnetic field analysis of the vibration generator 200. It is a figure which shows the analysis result of the magnetic flux density of the area | region shown by arrow O-X1. It is a figure which shows the analysis result of the magnetic flux density of the area | region shown by arrow OY1. It is a figure which shows the analysis result which showed the relationship between magnetic flux density, the length L2 of a 2nd permanent magnet, and cross-sectional radius R1.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a vertical cross-sectional schematic diagram showing a configuration of a vibration power generator 1 in the present embodiment. FIG. 2 is a dimension diagram showing dimensions of the first permanent magnet 111 and the second permanent magnet 112. In the present embodiment, the following will be described with the vertical direction and the horizontal direction defined as shown in FIG.

  A vibration generator 1 shown in FIG. 1 includes a cylindrical tubular member 2. The cylindrical member 2 is opened in the upper direction, and a plurality of openings are formed at the lower end. The cylindrical member 2 is formed of a magnetic material such as iron and a conductive material. An insulating sheet (not shown) is provided along the inner periphery and the outer periphery of the cylindrical member 2. With this insulating sheet, it is possible to avoid the possibility that the elastic spring 141 and the movable wiring 142 formed of a conductive material, which will be described later, come into contact with the inner wall surface of the cylindrical member 2 and the movable wiring 142 and the cylindrical member 2 are short-circuited. . The elastic spring 141 is an example of the elastic member of the present invention.

  A power generation unit 10 is provided inside the cylindrical member 2. A circuit unit 20 is provided above the power generation unit 10. The power generation unit 10 and the circuit unit 20 are electrically connected by the wiring member 30A and the wiring member 30B. The power generation unit 10 includes three first permanent magnets 111, two second permanent magnets 112, a magnet fixing member 120, a mover 130, an elastic spring 141, and a movable wiring 142. The circuit unit 20 includes a power supply circuit 21 having a rectifying function, a power storage function, and a constant voltage function. The power generated by the power generation unit 10 is supplied to the power supply circuit 21.

  As shown in FIG. 2, the 1st permanent magnet 111 and the 2nd permanent magnet 112 are ring-shaped, and are magnetized by the up-down direction. The vertical length L2 of the second permanent magnet 112 is shorter than the vertical length L1 of the first permanent magnet 111. In the present embodiment, the length L1 of the first permanent magnet 111 in the vertical direction is 75% of the outer diameter Dm of the first permanent magnet 111. The length L2 in the vertical direction of the second permanent magnet 112 is 25% of the outer diameter Dm.

  As shown in FIG. 1, the magnet fixing member 120 includes a pair of support parts 121 </ b> A and 121 </ b> B and a core part 122. The core part 122 is fitted to the support part 121A and the support part 121B. The support parts 121A and 121B and the core part 122 have a cylindrical shape. The core part 122 includes a core hole part 122A extending in the vertical direction at the center thereof. The support portions 121A and 121B are formed so that the outer diameter is substantially equal to the outer diameter Dm of the first permanent magnet 111 and the second permanent magnet 112, and the inner diameter is slightly larger than the outer diameter of the core portion 122. The core portion 122 is formed so that the outer diameter is smaller than the inner diameter of the first permanent magnet 111 and the inner diameter of the second permanent magnet 112. The length of the core portion 122 in the vertical direction is longer than the length in the vertical direction of three first permanent magnets 111 and two of the second permanent magnets 112.

  The magnet fixing member 120 is configured by inserting a core part 122 into an inner diameter portion of the support part 121B and fitting the core part 122 and the support part 121B. The lower end portion of the core portion 122 is fitted into an opening 23 formed at the center of the lower end surface of the tubular member 2 and is positioned so as to be disposed at the center of the tubular member 2. The core part 122 is inserted into the inner diameter portions of the three first permanent magnets 111 and the two second permanent magnets 112. In this inserted state, the three first permanent magnets 111 are fixed between the two second permanent magnets 112 in the vertical direction, and each of the three first permanent magnets 111 and the second permanent magnets 112 is adjacent to each other. It arrange | positions so that the same pole as a magnet may oppose.

  In a state where the first permanent magnet 111 and the second permanent magnet 112 are inserted into the core portion 122, the mover 130 is inserted into the core portion 122. In a state where the mover 130 is inserted into the core portion 122, the mover 130 is disposed outside the first permanent magnet 111 and the second permanent magnet 112. 121 A of support parts are fitted by the upper end of the core part 122 in which the 1st permanent magnet 111, the 2nd permanent magnet 112, and the needle | mover 130 were inserted. By this fitting, the support portion 121 </ b> A is fixed so as to close the upper open end of the tubular member 2.

  As shown in FIG. 2, each of the three first permanent magnets 111 and the two second permanent magnets 112 inserted into the core portion 122 is disposed so that the same polarity is opposite to the other permanent magnets adjacent to each other. Is done. Since the three first permanent magnets 111 and the two second permanent magnets 112 are disposed so that the same poles face each other, the magnetic flux density near the facing surface increases. However, when the first permanent magnet 111 and the second permanent magnet 112 are disposed so that the same poles face each other, the three first permanent magnets 111 and the two second permanent magnets 112 repel each other. Due to the matching properties, it is difficult to align the central axes of the first permanent magnet 111 and the second permanent magnet 112. Therefore, as shown in FIG. 1, core portions 122 are inserted into the inner diameter portions of the first permanent magnets 111 and the second permanent magnets 112, and the first permanent magnets 111 and the first permanent magnets 111 and the second permanent magnets 112 are used as axes. The two permanent magnets 112 are arranged so that the central axes thereof coincide with each other. The three first permanent magnets 111 and the two second permanent magnets 112 are sandwiched and fixed from both sides in the vertical direction by the support portions 121A and 121B so that the central axes thereof coincide with each other by the core portion 122. The

  The inner wall of the cylindrical member 2 formed from a magnetic material faces the side surface of the first permanent magnet 111 and the side surface of the second permanent magnet 112. With this arrangement, the magnetic flux generated from the first permanent magnet 111 and the second permanent magnet 112 is attracted to the cylindrical member 2 and confined in the cylindrical member 2. The higher the magnetic permeability of the magnetic material forming the cylindrical member 2, the greater the magnetic flux confinement effect by the cylindrical member 2, and the leakage magnetic field in the lateral direction of the vibration power generator 1 can be suppressed.

  A mover 130 is provided between the first permanent magnet 111 and the second permanent magnet 112 and the cylindrical member 2. The mover 130 is provided so as to be movable in a vertical direction, which is the longitudinal direction of the cylindrical member 2, in a space formed by the cylindrical member 2, the support portion 121 </ b> A and the support portion 121 </ b> B. The mover 130 includes a bobbin case 131 and a coil 135. The bobbin case 131 is made of a nonmagnetic material and has a cylindrical shape. Specific examples of the nonmagnetic material include resin materials such as PS and ABS. The movable wiring 142 has a length corresponding to the vertical movement of the movable element 130. The mover 130 is an example of the coil unit of the present invention.

  The inner diameter of the bobbin case 131 is larger than the outer diameter of the first permanent magnet 111 and the second permanent magnet 112, and the outer diameter of the bobbin case 131 is smaller than the inner diameter of the tubular member 2. A plurality of flanges 132 are formed on the bobbin case 131, and the arrangement pitch L3 is equal to the length L1 of the first permanent magnet 111.

  An enamel wire is wound around the outer periphery of the bobbin case 131 to form a coil 135. The enameled wire is wound in a region 133 between the flanges 132. The coil 135 is wound by a single enameled wire so as to be reversely wound in regions 133 adjacent to each other in the vertical direction. In the present embodiment, as described above, each of the three first permanent magnets 111 and the two second permanent magnets 112 are disposed so that the same poles face each other. appear. Since the coil 135 is wound so that one enamel wire is reversely wound in each of the upper and lower adjacent regions 133, the electromotive voltages generated in the plurality of regions 133 are efficiently added together.

  An elastic spring 141 made of a stainless steel tension spring or compression spring made of a conductive material and a nonmagnetic material is disposed below the mover 130. For example, a coil spring or the like is used for the elastic spring 141. A movable wiring 142 made of a conductive material is disposed on the upper part of the movable element 130. For example, the movable wiring 142 may be an enameled wire or a coil spring made of a conductive material in the same manner as the elastic spring 141. The upper end of the elastic spring 141 disposed at the lower part of the mover 130 is connected to the lower end side 135 </ b> B of the coil 135, and the lower end is connected to the wiring member 30 </ b> A connected to the circuit unit 20. The upper end side of the coil 135 provided on the bobbin case 131 is connected to the power supply circuit 21 arranged in the circuit unit 20 via the wiring member 30A. 135A is connected. At this time, the elastic spring 141 and the movable wiring 142 are electrically connected to the wiring members 30A and 30B and the coil 135.

(Description of the effect of the second permanent magnet)
The characteristics of the vibration generator 1 including the second permanent magnet 112 according to the present invention will be described in comparison with the vibration generator 200 not including the second permanent magnet 112 shown in FIG. The vibration power generator 200 does not include the second permanent magnet. Other configurations are the same as those of the vibration generator 1. 4 and 5 are magnetic field analysis results of the vibration generator 1 and the vibration generator 200, respectively. In the vibration generator 1 of FIG. 1 and the vibration generator 200 of FIG. 3, the permanent magnets are symmetrical with respect to the core 122. Because of this symmetry, FIGS. 4 and 5 both show the magnetic field analysis results on the right side from the shaft 122. In each drawing, in addition to the magnetic flux lines 150, a first permanent magnet 111, a second permanent magnet 112, and a cylindrical member 2 which are magnetic bodies are described. Further, arrows O-X1 and O-Y1 respectively indicate the region of the power supply circuit 21 shown in FIG. 1 and the region near the elastic spring 141 from the center of the region 133 of the coil 135 formed on the lowermost side. Is shown.

  As shown in FIGS. 4 and 5, due to the difference in distribution of the magnetic flux lines 150, the amount of magnetic flux lines clearly decreases due to the presence or absence of the second permanent magnet 112 in the region indicated by the arrows O-X 1 and O-Y 1. You can see that This is because the first permanent magnet 111 and the second permanent magnet 112 are disposed so that the same poles are opposed to each other, so that the magnetic flux lines radiated from the first permanent magnet 111 and the second permanent magnet 112 are disposed on the same pole facing surface. The radiated magnetic flux lines repel each other. Thereby, the magnetic flux lines radiated in the direction from the end surface of the first permanent magnet 111 toward the second permanent magnet 112 are bent in the left-right direction, and the direction from the end surface of the first permanent magnet 111 toward the second permanent magnet 112. Magnetic flux lines are not emitted. Furthermore, since the magnetic flux lines radiated in the opposite direction from the first permanent magnet 111 from the end face of the second permanent magnet 112 are attracted to a strong magnetic field near the same-polar facing surface, the magnetic flux in the opposite direction to the first permanent magnet 111. Density decreases.

  FIG. 6 is a graph showing the distribution of the absolute value | B | of the magnetic flux density in the region indicated by the arrow O-X1 shown in FIGS. That is, this is a graph for explaining the distribution of the leakage magnetic field in the vicinity of the power supply circuit 21. In the region indicated by the arrow O-X1, a horizontal position X1 (mm) from the position of the core portion 122 is indicated on the horizontal axis, and a magnetic flux density is indicated on the vertical axis (Tesla). In the region where the position X1 is zero, that is, in the central portion O of the power supply circuit 21 of the vibration generators 1 and 200, the leakage magnetic field of the vibration generator 1 is 90% or less less than the leakage magnetic field of the vibration generator 200.

  In general, a magnetic material is often used for electronic components constituting a power circuit. Since the vibration generator 1 of the present invention can greatly reduce the leakage magnetic field in the vicinity of the power supply circuit 21 as described above, it can reduce adverse effects on the wiring and electronic components on the power supply circuit 21. For this reason, it is possible to supply stable power without causing the power supply circuit 21 to malfunction or break.

  FIG. 7 is a graph showing the distribution of the absolute value | B | of the magnetic flux density at the arrow O-Y1 shown in FIG. 4 and FIG. That is, it is a graph for explaining the distribution of magnetic flux density from the central portion O of the region 133 of the coil 135 formed at the lowermost side to the position Y1 where the elastic spring 141 is located. In the region indicated by the arrow O-Y1, the position Y1 (mm) downward from the center position of the region 133 of the coil 135 formed on the lowermost side is shown on the horizontal axis, and the magnetic flux density is shown on the vertical axis (Tesla). Show. A vertical broken line Ye in the graph is a lower end portion of the region 133 when the movable element 130 is in a balanced position. This balance position is the position of the coil 135 when the external force due to vibration or the like is not acting on the vibration generator in a state where the vertical direction and the gravity direction coincide with each other. In the region where the position Y1 is closer to the central portion O than the vertical broken line Ye, the magnetic flux density is 30 to 50% higher when the second permanent magnet 112 is provided than when the second permanent magnet 112 is not provided. Further, in the region where the position Y1 is larger than 2 mm, that is, the region where the elastic spring 141 is mainly disposed, the magnetic flux density is higher when the second permanent magnet 112 is provided than when the second permanent magnet 112 is not provided. The magnetic field is greatly suppressed, and the leakage magnetic field can be reduced by 80% or more in the vicinity of Y1 of 6 mm.

  As described above, the vibration generator 1 of the present invention has a high magnetic flux density in the vicinity of the central portion O of the region 133 of the coil 135 formed on the lowermost side. That is, high power generation efficiency is obtained in the region 133. In addition, the vibration generator 1 of the present invention has a low magnetic flux density that becomes a leakage magnetic field in the vicinity of the elastic spring 141. SUS304 or SUS316 non-magnetic material is preferably used as the material of the elastic spring, but if it is placed in a strong magnetic field, it may be magnetized even if it is a non-magnetic material, and the spring performance will deteriorate. . In the vibration power generator 1 according to the present invention, the leakage magnetic field in the region where the elastic spring 141 is disposed is greatly reduced, so that stable vibration motion is possible.

(Explanation of the effect of the length of the second permanent magnet)
Subsequently, a change in magnetic flux density when the length L2 of the second permanent magnet 112 of the present embodiment is changed will be described with reference to FIG. This magnetic flux density is the same as that of the second permanent magnet 112 shown in FIG. 2 at the position where the elastic spring 141 is arranged in the region indicated by the arrow O-Y1 in FIG. A change in the absolute value | B | of the magnetic flux density when the length L2 is changed with respect to the cross-sectional radius R1 of the first permanent magnet 111 is shown. The cross-sectional radius R1 is a value obtained by dividing the outer diameter Dm shown in FIG. In FIG. 7, the value obtained by dividing the length L2 by the cross-sectional radius R1 is shown on the horizontal axis, and the absolute value of magnetic flux density (Tesla) is shown on the vertical axis. That is, in FIG. 7, when the value obtained by dividing the length L2 indicated by the horizontal axis by the cross-sectional radius R1 is zero, the second permanent magnet 112 is not provided, and only the first permanent magnet 111 is provided in the vibration generator 1. This is the case.

  As shown in FIG. 8, when the length L2 of the second permanent magnet 112 is 0.7 times or less the radius R1 of the first permanent magnet 111, the second permanent magnet 112 is not disposed. The magnetic flux density is also reduced. That is, it can be seen that the magnetic flux density of the leakage magnetic field is reduced, and the leakage magnetic field prevention of the second permanent magnet 112 is effective. Therefore, the length L2 of the second permanent magnet 112 in the vertical direction is preferably a length that is 70% or less of the cross-sectional radius R1 of the first permanent magnet 111. In particular, when the length L2 is around 50% of the cross-sectional radius R1, the magnetic flux density is greatly reduced. Further, if the length L2 of the second permanent magnet 112 is short, the magnetization direction of the second permanent magnet 112 may be reversed by the magnetic force from the first permanent magnet 111. The length L2 of the second permanent magnet 112 is such that the holding force of the second permanent magnet 112 is larger than the magnetic force of the first permanent magnet 111 so that the magnetization direction of the second permanent magnet 112 is not reversed. It is desirable that In addition, even when the lengths of the first permanent magnet 111 and the second permanent magnet 112 are relatively different from each other, the result of reducing the magnetic flux density of the leakage magnetic field is shown in the same manner as the experimental result shown in FIG.

(Example of use)
Next, the operation when the vibration power generator 1 of the present embodiment is used will be described. The vibration generator 1 is used as an energy harvester that generates electric power by vibration of a car or shaking of a bridge. When the vibration generator 1 is used, for example, when the vibration generator 1 is attached to an automobile and the automobile vibrates up and down, the vibration generator 1 vibrates. The external force applied to the vibration generator 1 by this vibration motion is transmitted to the movable element 130 to become kinetic energy, and the movable element 130 performs a vibration motion in the vertical direction in the cylindrical member 2.

  In the vibration power generator 1, the second permanent magnet 112 is arranged so that the same pole as the first permanent magnet 111 faces. With this arrangement, the leakage magnetic field of the second permanent magnet 112 on the side opposite to the side facing the first permanent magnet 111 can be reduced. By reducing the leakage magnetic field, the magnetic flux of the first permanent magnet 111 can be prevented from adversely affecting the inside and outside of the vibration generator 1. Along with the reduction of the leakage magnetic field, a high induced electromotive force can be generated due to the high magnetic flux density generated from the same pole facing surface. Further, contamination due to the magnetic material such as iron sand adhering to the vibration generator 1 can be suppressed.

  As described above, in the vibration power generator 1, the three first permanent magnets 111 and the two second permanent magnets 112 are arranged in the cylindrical member 2 so that the same poles face each other, and the outside is movable. The child 130 is configured to be reciprocally movable in the vertical direction. When the mover 130 moves in the cylindrical member 2, the coil 135 crosses the magnetic flux generated from the first permanent magnet 111 and the second permanent magnet 112, and an induced current is generated in the coil 135. When the mover 130 reciprocates, an alternating current is generated in the coil 135. The current generated in the coil 135 is transmitted to the power supply circuit 21 in the circuit unit 20 via the elastic spring 141, the movable wiring 142, and the wiring members 30A and 30B, and is rectified and stored.

  In the present embodiment, the coil 135 is formed of one enameled wire. Furthermore, the arrangement pitch L3 of each region 133 in which the coil 135 is formed is configured to be equal to the vertical length L1 of each of the three first permanent magnets 111 as described above. Therefore, when an external force is applied to the vibration generator 1 in the vertical direction, the mover 130 vibrates, and in each region 133, one high induced electromotive voltage generated by a strong magnetic field near each homopolar facing surface is one. As a result, a high voltage is obtained.

(Modification)
In addition, this invention is not limited to embodiment mentioned above, A various change is possible. For example, the cylindrical member 2 is not limited to a cylindrical shape, and a polygonal cylindrical member may be used. Further, the number of the permanent magnets 111, the interval between the flanges 132 of the bobbin case 131, and the number of the regions 133 delimited by the flanges 132 are not limited to the numbers described above. Further, the coil 135 may not be configured to be wound around the bobbin case 131 but may be an air-core coil.

  In this embodiment, the movable wire 142 is connected to the upper end 135A of the coil 135 and the elastic spring 141 is connected to the lower end 135B. However, the movable wire 142 is connected to the lower end 135B of the coil 135 and the elastic spring 141 is connected to the upper end 135A. May be connected, and both may be elastic springs 141.

  In the present embodiment, the wiring member 30A connected to the lower end of the elastic spring 141 is connected through the core hole portion 122A of the magnet fixing member 120 when connected to the circuit portion 20, but the fixed magnet member The configuration may be such that the coil 135 and the circuit unit 20 are electrically connected without passing the wiring member 30 </ b> A into the interior of 120. For example, instead of the magnet fixing member 120, a cylindrical or cylindrical conductor made of a nonmagnetic and conductive material is inserted into the support portions 121A and 121B, the first permanent magnet 111, and the second permanent magnet 112 having a hollow shape. May be. When the conductor is inserted through the support portions 121A and 121B, the first permanent magnet 111, and the second permanent magnet 112, the first permanent magnet 111 and the second permanent magnet 112 are fixed. The electric conductor and the wiring member 30 </ b> A connected to the lower end of the elastic spring 141 may be electrically connected, and the current generated in the coil 135 may be transmitted to the circuit unit 20. Moreover, if it is set as the structure which provides cylindrical insulation parts, such as an insulating sheet, on the outer peripheral surface of a conductor, it will contact and short-circuit with other members, such as the 1st permanent magnet 111 and the 2nd permanent magnet 112. There is no. Further, the elastic spring 141 may not be a coil spring but may be a leaf spring. This leaf spring is an example of the elastic member of the present invention.

  Although the mover 130 includes the bobbin case 131 and the coil 135, the mover 130 may not include the bobbin case 131. That is, the movable wiring 142 and the elastic spring 141 may be electrically connected to the conducting wire that constitutes the coil 135. At this time, the coil 135 is an example of the coil unit of the present invention.

DESCRIPTION OF SYMBOLS 1 Vibration generator 2 Cylindrical member 10 Power generation part 20 Circuit part 21 Power supply circuit 30A, 30B Wiring member 110 Fixed magnet part 111 1st permanent magnet 112 2nd permanent magnet 120 Magnet fixed member 122 Core part 122A Core hole part 130 Movable Child 131 Bobbin case 135 Coil 141 Elastic spring 142 Movable wiring 150 Magnetic flux line

Claims (3)

A tubular member;
A coil unit that is movably provided in the cylindrical member along the longitudinal direction of the cylindrical member, and is made of a nonmagnetic material and a conductive material;
A first permanent magnet fixed in the possible area of the coil unit and magnetized along the longitudinal direction;
A second permanent magnet having a length shorter than the length of the first permanent magnet in the longitudinal direction and having the same polarity as the first permanent magnet;
A vibration generator comprising:   2. The vibration generator according to claim 1, wherein a length of the second permanent magnet in the longitudinal direction is 70% or less of a cross-sectional radius of the first permanent magnet. The coil unit is held movably in the movable region by an elastic member having one end fixed inside the cylindrical member and the other end connected to the coil unit.
3. The vibration generator according to claim 1, wherein the elastic member is disposed closer to the second permanent magnet than the same-pole facing surface of the first permanent magnet and the second permanent magnet. 4.

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