Standalone power generation equipment

Abstract

To provide a self-supporting type power generation device that utilizes a completely self-sufficient energy source and is easily downsized.SOLUTION: A self-supporting type power generation device 100 includes: fixing members 21 and 22; a movable member 30; Casimir elements KD incorporated between the fixed members 21 and 22 and the movable member 30; and an energy conversion unit 50 for converting vibration of the movable member 30 into electric power. The Casimir elements KD act to maintain the vibration of the movable member 30 by lateral Casimir force.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a stand-alone power generating device that utilizes the Casimir force, and more particularly to a stand-alone power generating device that is small and does not require an energy source. [Background technology]

[0002] Known examples of independent power generation that does not require power transmission and distribution include photovoltaic power generation, which uses solar energy, and environmental power generation, which uses light, vibration, heat, etc. supplied from the surroundings. However, these power generation methods use unstable natural energy as an energy source, and the amount of power generated fluctuates depending on the environment. Completely independent power generation that is not dependent on the environment, etc., will pave the way for the future era of comprehensive distributed power generation. Note that nuclear power generation can essentially be said to be a completely independent form of power generation, but the facilities are large in scale and are not suitable for distributed small-scale power generation.

[0003] As a method of generating electricity using a completely autonomous energy source, a device that extracts energy from the phenomenon in which quantum fluctuations cause pair creation of electrons and positrons, which are negative and positive fluctuations, has been proposed (Patent Documents 1 to 3, etc.). In particular, Patent Document 1 proposes extracting the fluctuations in the form of resonance of an object and converting it into electricity, sandwiching a carbon nanotube as an elastic body between a pair of electrodes arranged opposite each other, and extracting the vibration of the Casimir force generated between the pair of electrodes with a piezoelectric cantilever.

[0004] However, it is not easy to fabricate a small power generating device that incorporates many fine cantilevers or carbon nanotubes, and it is also not easy to achieve a distance over which a force equivalent to work can be applied. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] U.S. Patent Publication No. 2020 / 0321514 [Patent Document 2] U.S. Patent No. 7,379,286 [Patent Document 3] U.S. Patent Publication No. 2020 / 0358376 Summary of the Invention

[0006] The present invention has been made in consideration of the above-mentioned background technology, and has an object to provide an independent power generation device that utilizes a completely independent energy source, is easily small, and can extract energy on a scale that is practical.

[0007] In order to achieve the above object, the present invention provides an independent power generating device comprising a Casimir element incorporated between a fixed member and a movable member, and an energy conversion unit for converting the vibration of the movable member into electric power, the Casimir element acting to maintain the vibration of the movable member by a lateral Casimir force, where the lateral Casimir force means a force generated along the extension direction of the conductor element body constituting the Casimir element.

[0008] In the above-mentioned stand-alone power generating device, the Casimir element acts to maintain the vibration of the movable member by the lateral Casimir force, so that the stroke of the lateral displacement that displaces one conductor element body constituting the Casimir element from the other conductor element body while maintaining a distance therebetween can be increased, enabling efficient extraction of energy. This allows for a large amount of power generation even in a small size. The Casimir element is an energy element that uses the Casimir force generated between a pair of conductor plates, and is based on the principle derived by Hendrik Casimir in 1948.

[0009] According to a specific aspect of the present invention, in the stand-alone power generating device, the Casimir element has a structure in which a pair of conductive flat plate members are arranged opposite each other. When the pair of flat plate members approach each other, a large Casimir force is generated.

[0010] According to another aspect of the present invention, the pair of flat plate members each have a group of projections periodically formed in the vibration direction, and the groups of projections are arranged opposite to each other. In this case, the movable member vibrates in the vibration direction parallel to the transverse Casimir force, enabling stable power generation.

[0011] According to yet another aspect of the present invention, the movable member is supported by the fixed member via an elastic member and is displaceable in a vibration direction parallel to the lateral Casimir force. In this case, the vibration of the movable member is efficient.

[0012] According to yet another aspect of the present invention, a power source array is provided in which a plurality of Casimir elements are combined and arranged in a comb-like shape, making it possible to integrate a large number of Casimir elements in a small space.

[0013] According to yet another aspect of the present invention, the Casimir element generates a Casimir force in a vibration direction perpendicular to the arrangement direction. [Brief description of the drawings]

[0014] [Figure 1] FIG. 2 is a plan view illustrating the independent power generation device according to the embodiment. [Diagram 2] FIG. 2A is an enlarged plan view of a Casimir element, and FIG. 2B is a diagram illustrating another example of a Casimir element. [Diagram 3] 13(A) and (B) are partially enlarged views illustrating modified examples of the Casimir element. [Figure 4] FIG. 13 is a partially enlarged view illustrating another modified example of the Casimir element KD. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] An independent power generating device according to one embodiment of the present invention will be described below with reference to Fig. 1 etc. The independent power generating device 100 is a generator that uses the Casimir force of the quantum electromagnetic vacuum field as an internal energy source, and includes first and second fixed members 21 and 22, a movable member 30, a Casimir drive unit 40, and an energy conversion unit 50.

[0016] The first and second fixed members 21, 22 are supported and fixed by anchors 71, 72. The movable member 30 is a rectangular plate-like body extending along the XZ plane, and is supported by anchors 73, 74 via four thin, narrow plate-like elastic members 61, making it movable in the X direction. The Casimir drive unit 40 includes a comb-tooth-shaped first drive unit 41 provided between the first fixed member 21 and the +X side end of the movable member 30, and a comb-tooth-shaped second drive unit 42 provided between the second fixed member 22 and the -X side end of the movable member 30.

[0017] The first driving section 41 is a power source array in which a flat plate-shaped member 41a fixed to the first fixed member 21 and a flat plate-shaped member 41b fixed to the movable member 30 are alternately arranged. That is, the first driving section (power source array) 41 is a Casimir element KD consisting of a pair of opposing flat plate-shaped members 41a, 41b, which are stacked or accumulated in the Z direction. The second driving section 42 is a power source array in which a flat plate-shaped member 42a fixed to the second fixed member 22 and a flat plate-shaped member 42b fixed to the movable member 30 are alternately arranged. That is, the second driving section (power source array) 42 is a Casimir element KD consisting of a pair of opposing flat plate-shaped members 42a, 42b, which are stacked or accumulated in the Z direction. The flat plate-shaped members 41a, 41b, 42a, and 42b constituting the Casimir element KD are conductive at least on the surface, and no potential is generated. That is, the electrodes of the flat plate members 41a, 41b, 42a, and 42b are earthed to the ground. The surface conductivity can be ensured by forming a metal film on the surfaces of the flat plate members 41a, 41b, 42a, and 42b. As a method for forming the metal film, various film forming methods that can realize the desired shape accuracy can be used. The flat plate members 41a, 41b, 42a, and 42b extend parallel to the XY plane perpendicular to the Z direction, which is the stacking direction, and have approximately the same shape. The flat plate members 41a and 41b are alternately arranged at equal intervals in the Z direction, and the flat plate members 42a and 42b are alternately arranged at equal intervals in the Z direction. However, in the first driving unit 41, the flat plate member 41a arranged relatively to the left in the drawing and the flat plate member 41b arranged to the right of it in the drawing constitute the Casimir element KD, and the flat plate member 41a arranged relatively to the right in the drawing and the flat plate member 41b arranged to the left of it in the drawing are relatively far apart and do not function as the Casimir element KD. The distance between the pair of flat plate members 41a, 41b that constitute the Casimir element KD is set to, for example, about 5 to 100 nm.In the second driving section 42, the flat plate member 42a arranged relatively to the right in the drawing and the flat plate member 42b arranged to the left of it in the drawing constitute a Casimir element KD, and the flat plate member 42a arranged relatively to the left in the drawing and the flat plate member 42b arranged to the right of it in the drawing are relatively far apart and do not function as a Casimir element KD. The distance between the pair of flat plate members 42a, 42b that constitute the Casimir element KD is set to, for example, about 5 to 100 nm.

[0018] The first fixing member 21 is supported by the anchor 71 via a leaf spring 71a extending parallel to the XY plane, and can be finely moved in the Z direction. The position adjustment device 81 is fixed to the anchor 71 and can move the first fixing member 21 in the Z direction, and can finely adjust the position of the first fixing member 21 relative to the anchor 71 in the Z direction. As a result, the spacing between the pair of flat-plate members 41a, 41b of the Casimir element KD constituting the first driving unit 41 can be increased or decreased. The second fixing member 22 is supported by the anchor 72 via a leaf spring 72a extending parallel to the XY plane, and can be finely moved in the Z direction. The position adjustment device 82 is fixed to the anchor 72 and can move the second fixing member 22 in the Z direction, and can finely adjust the position of the second fixing member 22 relative to the anchor 72 in the Z direction. As a result, the spacing between the pair of flat-plate members 42a, 42b of the Casimir element KD constituting the second driving unit 42 can be increased or decreased. The position adjustment devices 81 and 82 are formed of, for example, a piezoelectric element, and can be expanded or contracted to a desired length by a drive circuit (not shown).

[0019] The four elastic members 61 are flat plates that have a pair of flat surfaces extending parallel to the XY plane and extend elongated in the Z direction, and have approximately the same shape. The elastic members 61 are deformed flexibly due to their shape, and their tips can be displaced in the ±X directions with the anchors 73, 74 as their roots. As a result, when an external force in the X direction is applied to the movable member 30, the movable member 30 can be displaced by an amount of displacement that increases approximately as a linear function in response to the external force. In other words, the movable member 30 can elastically vibrate back and forth in the ±X directions when it receives forces from the first driving unit 41 and the second driving unit 42.

[0020] Although detailed description of the energy conversion unit 50 is omitted, it has electromagnetic elements such as a coil and a magnetic body fixed to the movable member 30, an electromagnetic element fixed to the case 98 of the stand-alone power generation device 100, and a rectifier circuit, and generates an electromotive force by the displacement of the electromagnetic element fixed to the movable member 30, and outputs a direct current.

[0021] In the above, the anchors 71, 72, 73, and 74 are aligned and fixed to the bottom plate portion 98b of the case 98. The first and second fixed members 21 and 22, the movable member 30, the Casimir driving portion 40, and the anchors 71, 72, 73, and 74 are a MEMS device 100a formed collectively by processing a Si wafer or the like, and are housed in the depressurized case 98. An independent power generating apparatus 100 including such a MEMS device 100a is called a comb-tooth microactuator.

[0022] In the above, it has been described that the bottom plate portion 98b of the case 98 is separate from the anchors 71, 72, 73, 74, etc., but the bottom plate portion 98b as well can be formed from a Si wafer, and the top plate (not shown) of the case 98, etc. can be fixed to the Si wafer substrate.

[0023] The MEMS devices 100a or the comb-tooth microactuators can be arranged two-dimensionally, for example, in the X and Z directions. Also, a large number of the comb-tooth microactuators can be stacked in the Y direction.

[0024] Referring to FIG. 2(A), a pair of opposing surfaces 11, 12 of the Casimir element KD are formed with protrusion groups 15, 16 whose thickness increases and decreases periodically. The convex parts 13, 14 constituting the protrusion groups 15, 16 extend uniformly in the Y direction perpendicular to the movable direction and the arrangement direction, and the protrusion amount increases and decreases sinusoidally in the X direction parallel to the movable direction. In the case of such a Casimir element KD, the transverse Casimir force generated in the X direction can be utilized, and a forced transverse vibration force can be generated in the movable direction in which the movable member 30 resonates. In other words, the Casimir element KD acts to maintain the vibration of the movable member 30 by the transverse Casimir force. The transverse Casimir force has been measured using an atomic force microscope (see Chen, et al., Phys. Rev. A66, 032113 (2002)). In the case of the illustrated Casimir element KD, the lateral Casimir force Ec is expressed by the following equation: z is the distance between the pair of opposing surfaces 11, 12, x is the overlap of the pair of opposing surfaces 11, 12 in the X direction, A1 and A2 are the amplitudes of the protrusions 13, 14, and Λ is the period of the protrusions 13, 14. Given by TIFF0007643934000001.tif13169.

[0025] 2B shows a reference example in which the pair of opposing surfaces 11, 12 of the Casimir element KD are flat. The lateral Casimir force Ec is expressed by the following equation: z is the distance between the pair of opposing surfaces 11, 12, x is the overlap of the pair of opposing surfaces 11, 12 in the X direction, and L is the depth width of the pair of opposing surfaces 11, 12 in the Y direction. In this case, the force becomes constant and it is difficult to generate vibration, so that electric power cannot be extracted effectively or efficiently.

[0026] A specific example will be described below. The thickness (depth in the Y direction) of the first and second fixed members 21, 22, the movable member 30, the Casimir driving unit 40, and the anchors 71, 72, 73, 74 constituting the MEMS device 100a was all set to 25 μm. The elastic member 61 has a length of 1000 μm in the Z direction, which is the longitudinal direction, and a thickness of 4 μm in the X direction. The thickness of the elastic member 61 in the Y direction is 25 μm as described above. The total number of comb teeth made up of the Casimir element KD as shown in FIG. 2(A) was set to 100. Assuming that the projections 15, 16 constituting the pair of opposing surfaces 11, 12 constituting the Casimir element KD are comb teeth of a metal conductor having a stepped cross section for the sake of convenience, and assuming that the interval between the opposing surfaces 11, 12 constituting the projections 15, 16 is 30 nm at the baseline and 10 nm at the bottom, the amplitude of the convex parts 13, 14 is 10 nm, the period of the convex parts 13, 14 is 40 nm, and the depth of the opposing surfaces 11, 12 is 25 μm, a transverse Casimir force of 10 nanonewtons is expected to be generated per period of the convex parts 13, 14. The longitudinal Casimir force in this case is about 33 nanonewtons per period of the convex parts 13, 14 when the transverse shift between them is a quarter period. In reality, smooth vibrations are generated by using a continuously changing shape (for example, a sine wave shape) rather than a stepped shape, but if the total number of Casimir elements KD constituting the Casimir element group of the above specific example is 100, the amplitude of the Casimir elements KD is equivalent to the initial overlap of 20 μm in the X direction of the pair of opposing surfaces 11, 12, and the frequency is 10 KHz, it is estimated that vibration energy of about 0.2 μW can be extracted from the Casimir element group. If the size of one Casimir element group is about 1 mm and the Casimir elements KD of the above specific example are arranged in a two-dimensional array, the maximum efficiency will be 20 μW / cm. 2 If it is further multi-layered and arranged three-dimensionally, the required thickness is 50 μm, which is twice the height of the comb teeth (25 μm), and the required power is 4 mW / cm 3 It is expected that this amount of vibrational energy can be extracted.

[0027] The stand-alone power generating device 100 of the above embodiment includes fixed members 21, 22, a movable member 30, a number of Casimir elements KD that are incorporated between the fixed members 21, 22 and the movable member 30 and generate a Casimir force in the same direction to vibrate the movable member 30, and an energy conversion unit 50 that converts the vibration of the movable member 30 into electric power, and the Casimir elements KD act to maintain the vibration of the movable member 30 by a transverse Casimir force. In this device, a number of Casimir elements KD can generate a transverse Casimir force in the same direction to vibrate the movable member 50. In addition, the Casimir elements KD are integrated, and the vibration frequency can be increased, so that the amount of power generation can be increased even if the device is small.

[0028] Although the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments. For example, the shapes and arrangements of the first and second fixed members 21 and 22, the movable member 30, the Casimir drive unit 40, etc. are merely examples, and various shapes and arrangements can be adopted depending on the degree of integration and the purpose.

[0029] 3(A) is a partially enlarged view illustrating a modified example of the Casimir element KD. In this case, two protrusions 13, 14 are formed on a pair of opposing surfaces 11, 12 of the Casimir element KD constituting the first driving unit 41 or the second driving unit 42. In this case, two protrusions 13, 14 are formed on each opposing surface 11, 12, but one protrusion 13, 14 may be formed on each opposing surface 11, 12. The height and width of the protrusions 13, 14 can be appropriately set in consideration of the mass of the movable member 30, the elastic modulus of the elastic member 61, the mechanism of the energy conversion unit 50, etc.

[0030] As shown in FIG. 3(B), the protrusions 13 and 14 may be protrusions having a rectangular cross section and extending in the Y direction.

[0031] Although not shown in the figure, the repeating period of the convex portions 13, 14 may be different between one opposing surface 11 and the other opposing surface 12, and the height of the convex portions 13, 14 may also be different between one opposing surface 11 and the other opposing surface 12.

[0032] 4 is a partially enlarged view for explaining another modified example of the Casimir element KD. In this case, the fixed member 120 is a thin plate and is fixed on the bottom plate portion 98b of the case, and the thin plate-shaped movable member 130 is disposed above the fixed member 120 and facing the fixed member 120. The movable member 130 is supported by an elastic member 61 and is displaceable in the X direction. A flat plate-shaped member 141a is formed in layers on the upper side of the fixed member 120, and a flat plate-shaped member 141b is formed in layers on the lower side of the movable member 130. A protrusion 13 is formed on the opposing surface 11 of the flat plate-shaped member 141a of the fixed member 120, which extends uniformly in the Z direction perpendicular to the X direction, which is the movable direction, and the amount of protrusion increases and decreases sinusoidally in the X direction parallel to the movable direction, forming a protrusion group 15. On the opposing surface 12 of the flat plate member 141b of the movable member 130, protrusions 14 are formed that extend uniformly in the Z direction perpendicular to the X direction, which is the movable direction, and whose protrusion amount increases and decreases sinusoidally in the X direction parallel to the movable direction, constituting a protrusion group 16. In this case as well, the movable member 130 is capable of reciprocating vibration in the X direction, and a group of Casimir elements KD formed by combining a pair of flat plate members 141a, 141b each generate a lateral Casimir force, which is a force in the ±X directions, and act to maintain the vibration of the movable member 30.

[0033] Although not explained above, the operation of the position adjustment devices 81, 82 is controlled by a microcomputer or other integrated control circuit. By providing a position sensor that detects the relative positions of the first and second fixing members 21, 22 with respect to the anchors 71, 72, the output of the position sensor can be processed by the integrated control circuit, enabling precise position control of the first and second fixing members 21, 22. The integrated control circuit can also be made to monitor the output of the energy conversion unit 50.

[0034] In the energy conversion unit 50, various methods such as power conversion by a piezoelectric element, electrostatic induction, and the like can be used in addition to electromagnetic induction, and the rotating shaft can be rotated gradually or static electricity can be gradually accumulated in association with the vibration of the movable member 30. By providing a battery in association with the energy conversion unit 50, it is possible to form a system that can stabilize the output current and deal with fluctuations in power consumption.

[0035] The stand-alone power generating device 100 can be used as an internal power source associated with IC chips, micro- and nano-machines, and the like. [Explanation of symbols]

[0036] Reference Signs List 11,12...opposing surfaces, 13,14...convex portions, 15,16...projection groups, 21,22...fixed members, 30...movable members, 40...Casimir drive units, 41a,41b,42a,42b...flat members, 50...energy conversion units, 50...movable members, 61...elastic members, 71,72,73,74...anchors, 71a,72a...leaf springs, 81,82...position adjustment devices, 98...case, 100...standalone power generation device, 100a...MEMS device, KD...Casimir element

Claims

1. A Casimir element is incorporated between the fixed member and the movable member; an energy conversion unit that converts the vibration of the movable member into electric power, The Casimir element has a structure in which a pair of conductive flat plate members are arranged opposite each other, The pair of flat plate-like members each have a group of projections that are periodically formed in a vibration direction that is a movable direction and that constitute a pair of opposing surfaces, The Casimir element acts to maintain the vibration of the movable member by a lateral Casimir force, assuming that the pair of flat members are earthed and there is no potential difference, in an independent power generation device.

2. An independent power generation device as described in claim 1, wherein the surface outer than the pair of opposing surfaces does not function as the Casimir element.

3. The lateral Casimir force Ec is expressed by: z is the distance between the pair of opposing surfaces; x is the overlap of the pair of opposing surfaces in the vibration direction; A1 and A2 are the amplitudes of the projection group; and Λ is the period of the projection group. The stand-alone power generating apparatus of claim 1 , wherein:

4. The stand-alone power generating device according to claim 1 , wherein the movable member is supported by the fixed member via an elastic member and is displaceable in a vibration direction parallel to the lateral Casimir force.

5. An independent power generation device according to any one of claims 1 to 4, comprising a power source array in which a plurality of the Casimir elements are combined and arranged in a comb-tooth shape.

6. The stand-alone power generating device according to claim 5 , wherein the Casimir element generates the lateral Casimir force in a movable direction perpendicular to the arrangement direction.

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