JP2009100523A - Permanent magnet element and oscillating generator, and acceleration sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new permanent magnet element, which can be used for a generator or an accelerator sensor, a generator which is simple, small and reliable which can reduce its parts count by using this permanent magnet element, and can set the generated voltage to high, and to provide an acceleration sensor. <P>SOLUTION: The permanent magnet element is constituted, being accommodated in an oscillating manner in the axial direction of a tubular body, in the nonmagnetic tubular body 2, where a coil 3 is wound around a peripheral face orthogonal to its axial direction, and it is obtained by combining a plurality of permanent magnets; the permanent magnet element 1 is constituted of a first permanent magnet body 5, where the respective homopoles of two permanent magnets are counterposed to each other, in the axial direction of the nonmagnetic tubular body and the axial centers are fixed with magnetic substances; and a second permanent magnet body 6 which is magnetically coupled with the axial outer face of the nonmagnetic tubular body of this first permanent magnet body. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a permanent magnet element and a generator and an acceleration sensor using the permanent magnet element. In particular, the present invention utilizes an abrupt magnetic flux change that occurs in the axial direction by vibrating an integrated magnet that is fixed with opposite poles facing each other. The present invention relates to a generator and an acceleration sensor that use an induced electromotive force generated in a coil installed on an outer peripheral surface.

Prior art 1 to prior art 4 are known as a generator and an acceleration sensor that utilize a phenomenon in which a current flows in a conductor when the conductor moves in a magnetic field (magnetic field) in a certain direction.
In Prior Art 1 (Patent Document 1), a pair of permanent magnets and a pair of permanent magnets are arranged in a housing so as to face each other with the same polarity and are separated from each other, and a voltage generated by moving a coil between these magnets. It is a structure connected to an operational amplifier. Since the moving distance of the coil is short, it is necessary to wind a large number of turns of the coil. Actually, a coil of 35 μmΦ wound with 2000 turns is used. The coil winding thickness is limited to a thickness of 0.1 mm.
However, since the prior art 1 does not consider the passage direction of the magnetic flux passing through the coil and the improvement of the magnetic flux amount even if the amount of magnetic flux is opposed to the same polarity, the coil winding requires advanced technology and voltage. The result is low. It is considered that the effect is small because it is intended to utilize the magnetic flux between facing opposite faces of the same polarity.
Further, in the prior art 1, an acceleration sensor by placing a coil at a position that is linearly linear within the pole can extract the highest detection value, and this structure detects the leakage flux. Only. Furthermore, when the coil is a thin wire of 35 μmΦ, it becomes expensive, and disconnection is likely to occur. Thus, when the product is finished, the product becomes unreliable.

Prior art 2 (patent document 2) is the same as document 1, and a hall element is placed in the center of the housing and a pair of permanent magnets are faced to the same polarity on both sides of the pipe and pressed against both sides of the pipe by repulsive force. . The permanent magnet moves by applying acceleration to the housing. At this time, a change in magnetic flux density at the center is detected by a Hall element. Therefore, in order to obtain an output voltage, it is necessary to pass a current through the Hall element.
However, although the prior art 2 is a method of capturing a change in magnetic flux density between permanent magnets, there is a problem that a power source is required for driving.

Prior art 3 (patent document 3) has a similar structure as in documents 1 and 2, and here, the circulating magnetic flux of the leakage magnet of the permanent magnet is detected as an induced electromotive force by a coil wound around the permanent magnet.
However, in the method of passing the leakage magnetic flux of the prior art 3 through the coil, the induced electromotive force is a weak voltage, and there is a problem that the voltage must be boosted in order to directly supply and use the load. It is difficult to use power for driving the load. This load is about light emitting illumination.

Prior art 4 (patent document 4) is also similar to documents 1, 2, and 3, and the leakage circulation magnetic flux is extracted as an induced electromotive force by a coil.
However, in the prior art 4, the leakage magnetic flux emitted from the movable magnet is passed through the coil, and the amount of magnetic flux passing is small and the induced electromotive force is also small. Therefore, the two coils are directly connected to increase the voltage. Even in this structure, the voltage when directly connected to the load is often insufficient, and it is necessary to wind a large number of coil turns.

  Prior art 1 to prior art 4 take out leakage circulation magnetic flux as an induced electromotive force with a coil, and power generation with these configurations relies on a method for obtaining leakage circulation magnetic flux as induction electromotive force. Therefore, the magnitude of the induced electromotive force is determined by the angle from the side surface of the magnetic axis to the core of the coil, its distance, and the changing speed. The product performance can be questioned by increasing the number of coil turns, so that the product can be finished to a product with a small separation distance, and the distance cannot be made too close. Therefore, the induced electromotive force has a limit. For example, the magnetic flux density emitted from the permanent magnets used in conventional permanent magnet generators and sensors that utilize this phenomenon is a cylindrical neodymium magnet with a diameter of 6 mm and a length of 20 mm. 0.466 (T), and the magnetic flux density decreases as the distance increases. For example, the magnetic flux density at a distance of 5 mm from the side surface is 0.0638 (T), and when the distance is 20 mm, the magnetic flux density decreases to about 0.00389 (T). The direction of the magnetic flux passing through the coil and the direction of the magnetic flux emitted from the oscillating magnet are released in the direction of the magnetic axis, and make a round through a path passing through the coil and circulating. This is a phenomenon that captures leakage magnetic flux.

In order to improve the above prior art and obtain a small portable generator with high output and high efficiency with low load for power generation and high generated voltage, the same poles face each other with a minute distance, and the length Integrates a plurality of permanent magnets magnetized in the direction, steeply changes the magnetic flux distribution, makes the direction of the magnetic flux approximately perpendicular to the winding direction of the coil, and makes the magnetic flux locally dense and integrated A plurality of coils are arranged in series on the outer periphery of the plurality of permanent magnets, the coils are arranged at appropriate intervals, and the winding directions are alternately reversed, and the integrated permanent magnet is moved. There is known a vibration generator that generates electric power (Patent Document 5).
However, even in this method, the structure of the integrated permanent magnet has not been studied. For example, the steepness or linearity of changes in magnetic flux distribution is not considered. Further, the leakage magnetic field in the case of the generator is not taken into consideration, and further, the acceleration sensor is not disclosed.

JP-A-6-27135 Japanese Patent Laid-Open No. 5-113448 JP 2002-281727 A JP-A-2001-508280 JP 2006-296144 A

  The present invention has been made in order to address the above-described problems. A novel permanent magnet element that can be used for a generator and an acceleration sensor, and the use of this permanent magnet element can simplify the number of components and reduce the size. An object of the present invention is to provide a generator and an acceleration sensor that are excellent in reliability and can generate a high voltage.

  The permanent magnet element of the present invention is used in a non-magnetic cylindrical body having a coil wound around an outer peripheral surface orthogonal to the axial direction so as to vibrate in the axial direction of the cylindrical body. The permanent magnet element is a first permanent magnet in which the same poles of two permanent magnets are opposed to each other in the axial direction of the non-magnetic cylindrical body, and the central portion in the axial direction is fixed with a magnetic body. And a second permanent magnet body magnetically coupled to the outer surface in the axial direction of the nonmagnetic cylindrical body of the first permanent magnet body.

Further, the same poles in the first permanent magnet body constituting the permanent magnet element are in close contact with each other.
The permanent magnet element composed of the first permanent magnet body and the second permanent magnet body includes a plurality of first permanent magnet bodies and a nonmagnetic cylinder of the first permanent magnet body. A second permanent magnet body magnetically coupled between the outer surfaces in the axial direction of the rod-like body, and the oppositely fixed magnetic poles of the plurality of first permanent magnet bodies have different magnetic poles across the second permanent magnet body It is characterized by that.

The vibration generator of the present invention includes a non-magnetic cylindrical body having a coil wound on an outer peripheral surface orthogonal to the axial direction, and the permanent magnet element according to the present invention housed in the cylindrical body. A voltage is generated in a coil wound around the outer peripheral surface of the nonmagnetic cylindrical body by vibrating the permanent magnet element in the nonmagnetic cylindrical body.
The vibration generator according to the present invention is characterized in that a magnetic cylindrical body that can be fitted to the outer periphery of a coil wound around the outer peripheral surface of the non-magnetic cylindrical body is provided.

  The acceleration sensor of the present invention includes a non-magnetic cylindrical body having a coil wound on an outer peripheral surface orthogonal to the axial direction, and the permanent magnet element according to the present invention housed in the cylindrical body. The acceleration applied to the magnet element is detected as electric power generated in a coil wound around the outer peripheral surface of the non-magnetic cylindrical body.

The permanent magnet element of the present invention includes a first permanent magnet body in which the same poles of two permanent magnets are opposed to each other in the axial direction of the non-magnetic cylindrical body, and the axial center portion is fixed with a magnetic body. Since the second permanent magnet body is magnetically coupled to the outer surface in the axial direction of the non-magnetic cylindrical body of the first permanent magnet body, the one-piece integrated type disposed opposite to the first permanent magnet body This is a mechanism that captures the change in the maximum value of the magnetic flux density emitted from the intermediate portion of the magnet and the minimum value of polarity conversion at the intermediate point of the permanent magnet as a change rate by the coil. As a result, when used as a permanent magnet element of a vibration power generator, the power ratio that the coil wound around the outer peripheral surface of the non-magnetic cylindrical body generates as an induced electromotive force becomes high efficiency. Further, when used as an acceleration sensor, the region where the rate of change of magnetic flux becomes constant becomes wider, so that the output becomes linear even with a large amplitude.
The above effect is achieved by fixing the first permanent magnet body with a magnetic body, and by making the same poles in the first permanent magnet body constituting the permanent magnet element face each other in close contact with each other. The magnetic flux density emitted from the battery becomes higher and the power generation efficiency increases. In addition, since the rate of change of the magnetic flux becomes constant at the opposite side, the linearity of the output as the acceleration sensor is improved.

The permanent magnet element of the present invention is composed of a plurality of first permanent magnet bodies and a magnetically coupled second permanent magnet body, which are fixedly opposed to each other in the plurality of first permanent magnet bodies. Since the magnetic poles are different from each other with the second permanent magnet body interposed therebetween, the first permanent magnet body and the second permanent magnet body can be easily magnetically coupled.
In addition, it becomes easy to construct a closed circuit of magnetic lines of force, and a restoring action to return to a fixed position even if the permanent magnet element is vibrated easily. Further, a force is generated to hold the permanent magnet element in the inner space of the non-magnetic cylindrical body, so that friction between the inner surface of the non-magnetic cylindrical body and the outer surface of the permanent magnet element can be reduced. The permanent magnet element can be easily vibrated.

The vibration generator according to the present invention includes a nonmagnetic cylindrical body having a coil wound around an outer peripheral surface orthogonal to the axial direction, and the permanent magnet element according to the present invention housed in the cylindrical body. As a result, power generation efficiency increases. As a result, it is possible to obtain a generator that can be directly connected to a load without being amplified by a separate power source or without increasing the number of coil turns and measuring the voltage boost.
In particular, since the magnetic cylindrical body that can be fitted to the outer periphery of the coil wound around the outer peripheral surface of the nonmagnetic cylindrical body is provided, an external leakage magnetic field can be reduced. In addition, by combining permanent magnet bodies with different magnetic poles fixed opposite to each other, the magnetic flux on the rebound surface circulates, and the leakage magnetic field can be reduced, thereby achieving stable power generation.

  Since the acceleration sensor of the present invention is composed of a non-magnetic cylindrical body in which a coil is wound around an outer peripheral surface orthogonal to the axial direction, and the permanent magnet element according to the present invention housed in the cylindrical body. The width in which the change of the magnetic flux becomes constant becomes wider. As a result, the output becomes linear even with a large amplitude. Further, since no power source is required for driving, a non-powered acceleration sensor can be obtained.

A permanent magnet element of the present invention that can be used in a vibration generator and an acceleration sensor will be described with reference to FIGS.
1 is a view showing a state in which a permanent magnet element is accommodated, FIG. 2 is a cross-sectional view of the permanent magnet element, FIGS. 3 and 4 are assembly perspective views of a first permanent magnet body, 5 and 6 are diagrams showing changes in magnetic flux density due to combinations of permanent magnet bodies when the opposing magnetic poles are changed.
The permanent magnet element 1 of the present invention is housed and used so as to vibrate in the axial direction in the non-magnetic cylindrical body 2. The non-magnetic cylindrical body 2 has a coil 3 wound around the outer peripheral surface thereof in a direction perpendicular to the axial direction of the cylindrical body 2. A magnetic cylindrical body 4 that can be fitted to the outer periphery of the coil 3 wound around the outer peripheral surface of the nonmagnetic cylindrical body 2 is preferably provided.

In the permanent magnet element 1 of the present invention, a first permanent magnet body 5 and a second permanent magnet body 6 are magnetically coupled to each other. In the present invention, “magnetic coupling” means that the S and N poles are fixed to each other by a magnetic force in a permanent magnet body.
As shown in FIG. 3, the first permanent magnet body 5 is prepared with a magnetic body 7 that faces, for example, the N poles of the permanent magnet bodies 5 a and 5 b and penetrates the central portions of the permanent magnet bodies 5 a and 5 b ( 3 (a)), the N poles opposed to each other are brought into close contact with each other so that the magnetic body 7 penetrates through the center (FIG. 3 (b)), and the head of the magnetic body 7 is caulked to thereby permanent magnet body 5a. And 5b are fixed to face each other (FIG. 3C).
As the fixing method, as shown in FIG. 4, the permanent magnet bodies 5a and 5b can be fixed opposite to each other, with the coupling portion of the magnetic bodies 7a and 7b having a male screw and female screw structure.

The permanent magnet bodies 5a and 5b may be opposed to each other with a slight gap. However, in the present invention, the permanent magnet bodies 5a and 5b are preferably fixed in close contact with each other.
FIG. 5A is a diagram showing a change in magnetic flux density in one permanent magnet body, and FIG. 5B is a magnetic flux density in two permanent magnet bodies in which different polarities are opposed to each other. FIG. 5C is a variation diagram of magnetic flux density in two permanent magnet bodies in which the same poles are opposed to each other at an interval of 1 mm, and FIG. 6A is an interval of 5 mm between the same poles. FIG. 6B is a change diagram of magnetic flux density in two permanent magnet bodies in which the same poles face each other at an interval of 10 mm.
In the case of one permanent magnet body, in the example in which the end face of the N pole of the magnet body is 0 mm and the length of the magnet body is 20 mm, the distance x in the length direction of the magnet body is taken as the horizontal axis, and the magnetic flux density B is When expressed on the vertical axis, the change in the magnetic flux density B has a convex distribution shown in FIG.
When the different magnetic poles of the two permanent magnet bodies are opposed to each other with a slight gap, a convex distribution with a constricted central part of the mountain is formed according to the gap (FIG. 5B). The constriction at the center of the mountain increases as the distance between the two permanent magnet bodies increases.
When the same magnetic poles of two permanent magnet bodies are made to face each other (N poles in FIG. 5 (c)), the magnetic flux density is reversed at the end faces of the facing N poles of the magnet body, and the separation distance increases. The linearity of the magnetic flux density is lost (FIG. 5 (c) to FIG. 6 (b)).
For this reason, in the first permanent magnet body 5, the permanent magnet bodies 5a and 5b are preferably fixed in close contact with each other.

  In the present invention, the separation distance between the permanent magnet bodies 5a and 5b that can effectively function as a vibration generator or an acceleration sensor may be within a range in which a change in magnetic flux density exhibits linearity. As a guideline, for example, the figure shows the magnetic field at the end of pure iron when the pure iron with a diameter of 6 mmΦ is adsorbed on a permanent magnet with a diameter of 6 mmΦ and a length of 5 mm, and the length is plotted on the horizontal axis. 7 shows. This permanent magnet corresponds to the magnetic coupling of the permanent magnet bodies 5 a and 6, and the pure iron corresponds to the magnetic body 7. FIG. 7 also shows a magnetic field of only a permanent magnet, the length of which is changed from the end. Up to a distance where the change of the magnetic field is linear, that is, up to a distance of 15 mm was used as a guideline for maintaining linearity. This length is for one of the magnets, and 30 mm, which is twice the length, is considered to be a length that maintains a straight line because of symmetry. It is considered that the linearity is maintained up to about six times the length of the permanent magnet.

The second permanent magnet body 6 that can be used in the present invention is a single permanent magnet body having N poles and S poles at both end faces.
As the first and second permanent magnet bodies that can be used in the present invention, a magnetized ferrite magnet, alnico magnet, samarium cobalt magnet, neodymium magnet, or the like can be used. Of these, samarium cobalt magnets and neodymium magnets are preferred in view of the strength of the magnetic force and the linearity of the demagnetization curve.
Also, permanent magnets such as cast magnets, sintered magnets, bonded magnets, and plastic magnets can be used using these materials.
The magnetic body 7 for coupling the first permanent magnet body 5 may be a soft magnetic body that is magnetized by the magnetic force of the permanent magnet, and is preferably a ferromagnetic body that is iron, cobalt, nickel, or an alloy thereof. .

In the permanent magnet element 1 of the present invention, as shown in FIG. 2, a first permanent magnet body 5 and a second permanent magnet body 6 are magnetically coupled to each other. Since the first permanent magnet body 5 has the same polarity coupled by a magnetic body, the magnetic pole on the outer surface of the permanent magnet body 6 magnetically coupled to the permanent magnet body 5 is the same as the magnetic pole on the outer surface of the permanent magnet body 5. It becomes the same pole. Therefore, the permanent magnet body 5N in which the N poles face each other, the permanent magnet body 5S in which the S poles face each other, and the second permanent magnet body 6 can be easily arranged by magnetic coupling. In addition, after forming a plurality of permanent magnet bodies in which the second permanent magnet bodies 6 are magnetically coupled to both sides of the first permanent magnet body 5, they may be magnetically coupled, or the first permanent magnet body. 5 may be directly magnetically coupled by the permanent magnet body 6.
By arranging the permanent magnet body 6 between the first permanent magnet bodies 5, the vibration width of the permanent magnet element 1 can be adjusted. In addition, since the first permanent magnet body 5 is a cylindrical magnet, the magnetic flux density is smaller than that of the permanent magnet body 6, so that the output can be increased.
In addition, if the number of the first permanent magnet bodies 5 is at least 2 or more, an effect is obtained when used for a vibration generator and an acceleration sensor, but by setting the number to 3 or more, the magnetic flux on the rebound surface circulates, Leakage magnetic field can be reduced and stabilization can be achieved.

  The vibration generator of the present invention will be described with reference to FIG. The vibration generator 9 includes a non-magnetic cylindrical body 2 in which the coil 3 is wound on the outer peripheral surface in a direction orthogonal to the axial direction of the cylindrical body 2, and a magnetic cylindrical body 4 that can be fitted to the outer periphery of the coil 3. And the permanent magnet element 1 accommodated in the cylindrical body 2. Springs 10 are provided at both ends of the nonmagnetic cylindrical body 2, and cushioning materials 8 are provided at both ends of the permanent magnet element 1.

A coil 3 is wound around the outer peripheral surface of the nonmagnetic cylindrical body 2 in a direction orthogonal to the axial direction, and the first permanent magnet body 5 in which the permanent magnet bodies 5a and 5b are fixed in close contact with each other. (1) A plurality of coils 3 are provided, and the winding directions thereof are such that adjacent coils are opposite to each other, and (2) the coil 3 is wound. The coil width being rotated is the length obtained by subtracting the amplitude of vibration from the length of the magnet element, (3) the interval between the coils 3 is the length obtained by subtracting the width of the coil from the length of the magnet element, and (4) the coil 3 When the number of magnets is several magnet elements, a large power generation output can be obtained. Here, the length L ₃ of the magnet element means a length obtained by magnetically coupling the second permanent magnet body 6 to both ends of the first permanent magnet body 5.

It is preferable to provide a plurality of coils 3 at the axially central portion of the nonmagnetic cylindrical body 2. In particular, when the permanent magnet element 1 has a plurality of first permanent magnet bodies 5, the output accompanying the vibration of the permanent magnet element 1 can be efficiently extracted by providing a plurality of coils 3.
The winding direction of the coil 3 is preferably such that adjacent coils are opposite to each other. Since the winding direction may be substantially reversed, all the coils are wound in the same direction, and the winding start ends and winding end ends of adjacent coils are alternately switched and connected in series. May be.

The coil width L _{1 around} which the coil 3 is wound is preferably a length obtained by subtracting the amplitude of vibration from the length L ₃ of the magnet element. By setting the length, the magnet element can be vibrated in a region where the magnetic flux density changes sharply, so that power generation efficiency is improved.

The distance L ₂ between the coils 3 is preferably a length obtained by subtracting the length L ₁ of the coil width from the length L ₃ of the magnet element. By setting this length, the change in the magnetic flux density becomes a target position with respect to the amplitude of vibration, so that the linearity of the output waveform and the power generation efficiency are improved.

  The number of coils is preferably several magnet elements. By setting the number of magnet elements to several, it is possible to set the magnetic flux density at a position where the magnetic flux density changes sharply, thereby improving the power generation efficiency.

  The magnetic cylindrical body 4 that can be fitted to the outer periphery of the coil 3 is preferably formed of a ferromagnetic material. FIG. 9 shows the distribution of magnetic lines of force when the magnetic cylindrical body 4 is provided. In FIG. 9, the magnetic lines 11 and 12 are indicated by broken lines. As shown in FIG. 9, an external leakage magnetic field can be reduced by making the magnetic cylindrical body 4 a ferromagnetic body. Further, even if the magnet element 1 is vibrated, the restoring force for returning to a fixed position can be applied to the magnet element 1 by the action of the magnetic lines of force 11 and 12. As this ferromagnetic material, the same material as the magnetic material used for coupling the first permanent magnet body 5 can be used.

The length L ₄ of the magnetic cylindrical body 4 is preferably a length obtained by multiplying the length L ₃ of the magnet element by the number of magnet elements and doubling the amplitude of vibration. With this length, the leakage magnetic field and friction can be reduced, and the output can be increased.

  In the vibration power generator of the present invention, the shape of the nonmagnetic cylindrical body 2 may be any shape that can accommodate the permanent magnet element and vibrate in the axial direction of the cylindrical body. Since the magnetic flux density is considered to be uniform on the peripheral surface, it is preferable that the permanent magnet element 1 has a columnar cross section and the non-magnetic cylindrical body 2 has a cylindrical cross section. In addition, when using as a power supply of thin apparatuses, such as a mobile telephone, the nonmagnetic cylindrical body 2 can be made into a cross-sectional flat cylindrical shape.

The material of the non-magnetic cylindrical body 2 has a mechanical strength that allows the magnet element 1 to be housed inside and vibrates, and any non-magnetic material can be used. For example, plastics, ceramics, and composite materials thereof can be used. Among them, it is preferable to use a resin or a resin composition excellent in mechanical strength and slidability. It is also preferable to form a slidable coating film inside the non-magnetic cylindrical body 2.
The coil 3 can be used by winding a winding having a circular or square cross section.

  As a method for manufacturing the vibration generator shown in FIG. 8, the magnet element 1, the nonmagnetic cylindrical body 2, the coil 3, and the magnetic cylindrical body 4 can be prepared and assembled in sequence. In addition, the magnetic cylindrical body 4 and the coil 3 can be housed in the mold, and the nonmagnetic cylindrical body 2 can be formed by an integral molding method.

The vibration generator of the present invention generates a large amount of power by increasing the weight of the outside, such as increasing the number of turns of the coil 3 by vibrating the magnet element 1 integrated inside the non-magnetic cylindrical body 2. Is born. Therefore, power can be taken out without requiring an operational amplifier or the like.
In addition, since the resonance frequency can be set from several Hz to several tens of Hz, which is a frequency corresponding to the movement of the person, the power generation effect can be increased by operating near the resonance frequency when the person carries the object. In addition, a DC power supply can be obtained by using a rectifier circuit.
It can be used as a power source for digital camera power supplies, watches, various remote controls, personal computers / mouses, and electric toothbrushes. As an alternative to dry batteries, it can be used for various toys, power supplies for emergency disaster equipment, and flashlights. It can be used for tidal power generators, earthquake alarms, mobile phone rechargeable batteries, thermos bottles, traffic lights, etc.

The acceleration sensor of the present invention operates by detecting the acceleration applied to the permanent magnet element as electric power generated in the coil in the vibration generator. By adjusting the length of the magnet body 7, it is possible to cope with a large amplitude at a low frequency. In that case, from the result of FIG. 7, in order to maintain linearity, the length of the magnetic body can be separated up to three times the length L ₃ of the magnet element.
In addition, since linearity is maintained and the output becomes large, an operational amplifier or the like is not necessary. Therefore, a parasitic vibration sensor that does not require a power source for driving can be obtained.
As a use, it can be applied to a sensor at the time of collision of an automobile and an operation sensor of an air bag.

Example 1
A neodymium cylindrical permanent magnet having an outer diameter of 24 mmφ, an inner diameter of 5 mmφ, and a length of 4 mm was prepared and processed so that one end face of the inner diameter portion was expanded to have a funnel-shaped cross section in the axial direction. This neodymium cylindrical permanent magnet is magnetized, and the two permanent magnets are S poles or N poles, with the small diameter portion closely contacting each other in the axial direction, and a magnetic material (material is penetrating through the center) It was fixed by caulking with Permalloy (PC78)). A permanent magnet element was obtained by magnetically coupling a magnetized neodymium cylindrical permanent magnet having an outer diameter of 23.5 mmφ and a length of 25 mm on both sides of the two closely fixed permanent magnets. A permanent magnet element in which N poles were fixed, a permanent magnet element in which S poles were fixed, and a permanent magnet element in which N poles were fixed were sequentially magnetically coupled to obtain a permanent magnet element. A SUS spring was attached as a buffer member to the outer surface in the axial direction of the permanent magnet element.

Example 2
A cylinder made of polyacetal resin (Duracon) with an outer diameter of 54 mmφ, an inner diameter of 27.2 mmφ, and a length of 160.6 mm is prepared, and the central outer peripheral portion of this cylinder is cut out, and a coil with a coil width of 25 mm is spaced by 2 mm. 3 embedded. The winding directions of the coils were different from each other. Further, the coil was wound by 1500 turns of a 0.4 mmφ polyester wire. The connection of the three coils was connected in series so that the winding directions were different, and the coil terminal was connected to the output terminal. A magnetic cylindrical body (material is permalloy (PC78)) having a thickness of 2 mm and a length of 100 mm was fitted and fixed to the outer periphery of the coil.
The permanent magnet element obtained in Example 1 was inserted into the cylinder, and the cylinder was sealed to obtain a vibration generator.

The obtained vibration generator was installed in a vibrator (MODEL 113 manufactured by Air Brown) so as to vibrate in the cylindrical axis direction, and the output was measured by changing the frequency from 1 Hz to 20 Hz. The results are shown in FIGS.
10 shows the output waveform when the frequency of the vibrator is 3 Hz by a broken line, and FIG. 11 shows the output waveform when the frequency is 5 Hz by a broken line. FIG. 12 shows the output voltage, and FIG. 13 shows the output power.
No measurable output was seen at frequencies of 1 Hz and 2 Hz, and a maximum output was shown at a frequency of 3 Hz, although not a sine wave. A normal sine wave output was observed at 5 Hz.

Example 3
The vibration generator obtained in Example 2 was evaluated as an acceleration sensor.
Using the same vibrator as in Example 2, the output value when the acceleration G and the load resistance were changed was measured. The results are shown in Table 1.

  The present invention has features of simple, small size, high performance and high reliability as a generator and an acceleration sensor by moving a circulating magnetic flux released between repulsive magnets. It can be used as a power source for digital camera power supplies, watches, various remote controls, personal computers / mouses, and electric toothbrushes. As an alternative to dry batteries, it can be used for various toys, power supplies for emergency disaster equipment, and flashlights. It can be used for tidal power generators, earthquake alarms, mobile phone rechargeable batteries, thermos bottles, traffic lights, etc.

It is a figure which shows the state in which the permanent magnet element is accommodated. It is sectional drawing of a permanent magnet element. It is an assembly perspective view of the 1st permanent magnet body. It is another assembly perspective view of the 1st permanent magnet body. It is a figure showing the change of the magnetic flux density by the combination of a permanent magnet body. It is another figure showing the change of the magnetic flux density by the combination of a permanent magnet body. It is an output figure when the separation distance of a permanent magnet body is changed. It is a figure which shows the vibration generator of this invention. It is a figure which shows distribution of the magnetic force line at the time of providing a magnetic cylindrical body. It is a figure which shows the output waveform when the frequency of a vibration exciter is 3 Hz. It is a figure which shows the output waveform when the frequency of a vibration exciter is 5 Hz. It is a figure which shows an output voltage when changing the frequency of a vibration exciter. It is a figure which shows output electric power when changing the frequency of a vibration exciter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Permanent magnet element 2 Nonmagnetic cylindrical body 3 Coil 4 Magnetic cylindrical body 5 1st permanent magnet body 6 2nd permanent magnet body 7 Magnetic body 8 Buffer material 9 Vibration generator 10 Spring 11 Magnetic field line 12 Magnetic field line

Claims (6)

Permanent magnet element obtained by combining a plurality of permanent magnets in a non-magnetic cylindrical body having a coil wound around an outer peripheral surface orthogonal to the axial direction and housed so as to vibrate in the axial direction of the cylindrical body Because
The permanent magnet element includes a first permanent magnet body in which the same poles of two permanent magnets are opposed to each other in the axial direction of the cylindrical body, and the central portion in the axial direction is fixed with a magnetic body. A permanent magnet element comprising: a second permanent magnet body magnetically coupled to an outer surface in the axial direction of the cylindrical body of the permanent magnet body.   2. The permanent magnet element according to claim 1, wherein the same poles in the first permanent magnet body are in close contact with each other.   The permanent magnet element composed of the first permanent magnet body and the second permanent magnet body includes a plurality of the first permanent magnet bodies and an axial direction of the cylindrical body of the first permanent magnet bodies. A second permanent magnet body magnetically coupled between outer surfaces, and the oppositely fixed magnetic poles of the plurality of first permanent magnet bodies are different from each other across the second permanent magnet body. The permanent magnet element according to claim 1 or 2, characterized in that A non-magnetic cylindrical body having a coil wound on an outer peripheral surface orthogonal to the axial direction; and a permanent magnet element housed in the cylindrical body, the permanent magnet element being vibrated in the non-magnetic cylindrical body In the vibration generator that generates a voltage in the coil,
The vibration generator according to claim 1, wherein the permanent magnet element is the permanent magnet element according to claim 1.   The vibration generator according to claim 4, wherein a magnetic cylindrical body that can be fitted to an outer periphery of the coil is provided. A non-magnetic cylindrical body in which a coil is wound on an outer peripheral surface orthogonal to the axial direction and a permanent magnet element housed in the cylindrical body, and an acceleration applied to the permanent magnet element is generated in the coil In the acceleration sensor that detects it as
An acceleration sensor, wherein the permanent magnet element is the permanent magnet element according to claim 1, claim 2, or claim 3.

Images