Mechanical energy storage device

Abstract

To provide a mechanical power storage device capable of suppressing an increase in facility cost by reducing a load on the entire facility due to a restoring force of an elastic body.SOLUTION: A core 5 is fixedly installed at the center in the longitudinal direction in a cylindrical casing 4, sliders 6 are slidably housed on both sides in the longitudinal direction in the casing 4 with the core 5 interposed therebetween, coil springs 2 (resilient bodies) expandable and contractible in the longitudinal direction of the casing 4 are housed between the core 5 and both the sliders 6, the both sliders 6 are drawn to the core 5 to compress the both coil springs 2, the compressed coil springs 2 are converted into physical energy to be stored, and kinetic energy is generated when the coil springs 2 are released to be restored to an initial state.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a mechanical electricity storage device. [Background technology]

[0002] In recent years, research and development into renewable energy sources such as sunlight, wind, and biomass fuels has been progressing. However, this type of renewable energy is known to have large fluctuations when output as electricity via generators, etc., and does not necessarily correspond to electricity demand. Therefore, it is essential to take some measures to temporarily store surplus electricity during periods of low demand.

[0003] Until now, when such temporary storage of electricity was desired, chemical batteries such as lithium ion batteries have been used, and prior art documents relating to the power generation systems using renewable energy as described above, such as Patent Document 1 below, are already well known.

[0004] Chemical batteries such as the aforementioned lithium-ion batteries have problems such as being prone to deterioration in a short period of time and being difficult to recycle after deterioration, and there is a demand for new means of storing electricity that are different from existing chemical batteries.

[0005] More specifically, a mechanical energy storage device is being considered that uses surplus electricity to maintain a resilient body in a compressed or extended state, converts the electricity into physical energy known as the resilience of the resilient body, and temporarily stores it, and then drives a generator with the kinetic energy generated when the resilient body is released and returns to its initial state, thereby enabling electricity to be extracted. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-105667 Summary of the Invention [Problem to be solved by the invention]

[0007] However, when converting practically sufficient electricity into physical energy and temporarily storing it, it is necessary to firmly fix one end of a relatively large and long elastic body while pushing in the other end to compress the elastic body, or pulling the elastic body to extend it, thereby generating a large restoring force. Therefore, a strong reinforcing structure must be provided to withstand this restoring force, thereby increasing the strength of the entire facility, which poses the problem of unavoidable increases in facility costs.

[0008] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a mechanical energy storage device that can reduce the load on the entire facility caused by the restoring force of the elastic body and suppress rising equipment costs. [Means for solving the problem]

[0009] The present invention relates to a mechanical electricity storage device characterized in that a core is fixedly installed in the longitudinal center of a cylindrical casing, sliders are housed on both longitudinal sides of the casing on either side of the core so that they can slide freely, and elastic bodies that can expand and contract in the longitudinal direction of the casing are housed between the core and the two sliders, and electricity is stored by converting the energy into physical energy by pulling the two sliders toward the core and compressing the two elastic bodies, and then generating electricity from the kinetic energy generated when the two elastic bodies are released and restored to their initial state.

[0010] In this case, when both sliders are pulled toward the core and both springs are held in a compressed state, electricity is temporarily stored in the form of physical energy converted into the restoring force of the two springs.When the two springs are released from this stored state, electricity is generated by the kinetic energy generated when the two springs return to their initial state, and the stored electricity is extracted.

[0011] In such a mechanical energy storage device, the restoring force of both elastic bodies held in a compressed state acts as a compressive force toward the middle core by reacting with both sliders, and no large load is placed on surrounding structures such as the casing, so there is no need to provide the entire facility with a strong reinforcing structure that can withstand the restoring force of both elastic bodies.

[0012] Furthermore, in order to implement the present invention more specifically, it is preferable to provide a drum that winds up a cable-like body arranged between the core and both sliders to draw the both sliders toward the core and compress the both elastic bodies, a motor generator that is connected to the drum via a speed reducer so as to be able to transmit torque, and a brake mechanism that locks the axial rotation of the motor generator.

[0013] In this case, the drum may be placed inside the core and the cord-like member arranged between the core and both sliders may be wound up by the drum, or the drum may be placed outside the casing and the cord-like member arranged between the core and both sliders may be led out of the core to the outside of the casing and wound up by the drum. [Effects of the Invention]

[0014] According to the mechanical energy storage device of the present invention, the load on the entire facility caused by the restoring force of the resilient body can be reduced, and there is no need to improve the strength of the entire facility by providing a strong reinforcing structure that can withstand the restoring force of the resilient body. It is sufficient to take relatively simple measures such as reinforcing the core with a tension structure or the like to create a structure that is resistant to compression, which has the excellent effect of significantly suppressing the rise in equipment costs when implementing a mechanical energy storage device. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a plan view showing a first embodiment of the present invention. [Figure 2] FIG. 2 is a plan view showing a state in which the wire rope has been completely wound onto the drum of FIG. 1. [Figure 3] FIG. 10 is a plan view showing a second embodiment of the present invention. [Figure 4] FIG. 4 is a plan view showing a state in which the wire rope has been completely wound onto the drum of FIG. 3. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0017] 1 and 2 are plan views showing a first embodiment of the mechanical electricity storage device of the present invention. The mechanical electricity storage device 1 shown here is configured to store electricity by compressing a coil spring 2 (resilient body) by pulling it when a wire rope 3 (cord-like body) is wound up, converting the energy into physical energy, and then generating electricity using the kinetic energy generated when the coil spring 2 is released and restored to its initial state.

[0018] More specifically, a core 5 is fixedly installed in the longitudinal center of a cylindrical casing 4, and sliders 6 are housed slidably on both sides of the core 5 in the longitudinal direction within the casing 4, with expandable and contractible coil springs 2 housed between the core 5 and each of the sliders 6.

[0019] Here, in this embodiment, the core 5 is formed by fixing two partitions 5a to the casing 4 by bolts or the like, and in the storage space 5b partitioned by each of the partitions 5a, a drum 7 is arranged which winds up the wire rope 3 arranged between the core 5 and both sliders 6 through the openings 5c of each of the partitions 5a, thereby drawing both sliders 6 toward the core 5 and compressing both coil springs 2.

[0020] In other words, this drum 7 has winding portions for each wire rope 3 on both sides of its axial direction, so that each wire rope 3 arranged between the two sliders 6 can be wound simultaneously by rotating the drum 7.

[0021] In addition, one axial end of the drum 7 is rotatably supported by a plumber 12 (a bearing unit that stores a rolling bearing inside) outside the casing 4, and the other end is connected to a motor generator 9 via a speed increase / reduction gear 8, also outside the casing 4, so that torque can be transmitted, and the axial rotation of the motor generator 9 is locked by a brake mechanism 10.

[0022] Furthermore, a tension structure 11 (reinforcement structure) is provided between the partitions 5a to resist the restoring force that is received when the two sliders 6 are pulled together and the two coil springs 2 are compressed. The tension structure 11 may be a plurality of rods that are installed between the two partitions 5a on the inner periphery of the core 5, or may be a thick cylindrical body that is interposed between the two partitions 5a.

[0023] Furthermore, the opposing sides of the partition wall 5a and the slider 6 are provided with a convex shape so that they can fit into the end of the coil spring 2 and hold the end, and the body of the slider 6 is fitted with a resin outer skin so that it can slide smoothly with low friction against the inner surface of the casing 4.

[0024] Here, the illustrations in Figures 1 and 2 are merely schematic illustrations for the convenience of explaining the invention, and the scale of the coil spring 2, drum 7, tension structure 11, etc. does not necessarily correspond to the actual equipment, and it goes without saying that the casing 4 may be laid out not only horizontally but also vertically, for example.

[0025] In this case, when the motor generator 9 is driven by electricity to wind the wire rope 3 onto the drum 7, and the state shown in Figure 1 is changed to the state shown in Figure 2, and both sliders 6 are pulled toward the core 5 to compress both coil springs 2, and the axial rotation of the motor generator 9 is locked by the brake mechanism 10, electricity is temporarily stored in the form of physical energy converted into the restoring force of both coil springs 2, and when the brake mechanism 10 is unlocked from this stored state, the kinetic energy generated when both coil springs 2 are released and restored to their initial state (the state shown in Figure 1) causes the wire rope 3 to be unwound from the drum 7, and the motor generator 9, which is connected to the drum 7 so as to be able to transmit torque via the speed reducer 8, is driven as a generator and electricity is extracted.

[0026] In such a mechanical energy storage device 1, the restoring force of both coil springs 2 held in a compressed state acts as a compressive force toward the intermediate core 5 as a reaction force on both sliders 6, and no large load is placed on the surrounding structures such as the casing 4, so there is no need to provide the entire facility with a strong reinforcing structure that can withstand the restoring force of both coil springs 2.

[0027] As described above, according to the above embodiment, the load on the entire facility due to the restoring force of the coil spring 2 can be reduced, and there is no need to improve the strength of the entire facility by providing a strong reinforcing structure that can withstand the restoring force of the coil spring 2. It is sufficient to take a relatively simple measure of reinforcing the core 5 with a tension structure 11 or the like to create a structure that is resistant to compression, so that it is possible to significantly suppress increases in facility costs when implementing the mechanical energy storage device 1.

[0028] FIGS. 3 and 4 show a second embodiment of the mechanical electricity storage device 1 of the present invention. Whereas the first embodiment described above has a drum 7 disposed within the core 5, and the wire rope 3 routed between the core 5 and both sliders 6 is wound up by the drum 7, the drum 7 is disposed outside the casing 4 together with the speed reducer 8, motor generator 9, and brake mechanism 10, and the wire rope 3 is led out of the casing 4 from the core 5 via pulleys 13 and the like and wound up by the drum 7. Parts that are assigned the same reference numerals as in FIGS. 1 and 2 represent the same parts.

[0029] Even in this case, when the motor generator 9 is driven with electricity to wind the wire rope 3 onto the drum 7, and the state shown in Figure 3 is changed to the state shown in Figure 4, and both sliders 6 are pulled toward the core 5 to compress both coil springs 2, and the axial rotation of the motor generator 9 is locked by the brake mechanism 10, electricity is temporarily stored in the form of physical energy converted into the restoring force of both coil springs 2, and when the brake mechanism 10 is unlocked from this stored state, the kinetic energy generated when both coil springs 2 are released and restored to their initial state (the state shown in Figure 3) causes the wire rope 3 to be unwound from the drum 7, and the motor generator 9, which is connected to the drum 7 so as to be able to transmit torque via the speed reducer 8, is driven as a generator and electricity is extracted.

[0030] In such a mechanical energy storage device 1, the restoring force of both coil springs 2 held in a compressed state acts as a compressive force toward the intermediate core 5 as a reaction force on both sliders 6, and no large load is placed on the surrounding structures such as the casing 4, so there is no need to provide the entire facility with a strong reinforcing structure that can withstand the restoring force of both coil springs 2.

[0031] As described above, in the above embodiment, the load on the entire facility due to the restoring force of the coil spring 2 can be reduced, and there is no need to improve the strength of the entire facility by providing a strong reinforcing structure that can withstand the restoring force of the coil spring 2. It is sufficient to take a relatively simple measure of reinforcing the core 5 with a tension structure 11 or the like to create a structure that is resistant to compression, so that it is possible to significantly suppress increases in equipment costs when implementing the mechanical energy storage device 1.

[0032] It should be noted that the mechanical energy storage device of the present invention is not limited to the above-described embodiments, and the resilient body may be of a type other than a coil spring, the cord-like body may be of a type other than a wire rope, and the cord-like body may be routed between the core and both sliders by moving back and forth multiple times via pulleys or the like. Of course, various other modifications can be made within the scope of the present invention without departing from the spirit of the present invention. [Explanation of symbols]

[0033] 1 Mechanical energy storage device 2 Coil spring (spring) 3 Wire rope (cord) 4 Casing 5 cores 6 Slider 7. Drums 8 Speed ​​increase / reduction gear 9. Motor generator 10 Brake mechanism

Claims

1. A mechanical electricity storage device comprising: a core fixedly installed in the longitudinal center of a cylindrical casing; sliders slidably housed on either side of the core in the longitudinal direction within the casing; and elastic bodies that can expand and contract in the longitudinal direction of the casing are housed between the core and the two sliders; the two sliders are pulled toward the core to compress the two elastic bodies, thereby converting the energy into physical energy for storage, and the kinetic energy generated when the two elastic bodies are released and restored to their initial states generates electricity.

2. 2. The mechanical electricity storage device according to claim 1, further comprising: a drum that winds up a cable disposed between the core and both sliders to draw the both sliders toward the core and compress the both elastic bodies; a motor generator connected to the drum via a speed increase / decrease gear so as to be able to transmit torque; and a brake mechanism that locks axial rotation of the motor generator.

3. 3. The mechanical electricity storage device according to claim 2, wherein a drum is disposed within the core, and a cord-like body arranged between the core and both sliders is wound around the drum.

4. 3. The mechanical electricity storage device according to claim 2, wherein a drum is disposed outside the casing, and the cord-like member disposed between the core and both sliders is led out from the core to the outside of the casing and wound up by the drum.

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