JP2004304920A - Flywheel power storing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flywheel power storing device that makes it possible to reduce the number of required electric motors and electric components and that can rotate two flywheels reliably in directions opposite to each other. <P>SOLUTION: This device includes the electric motor 6 that drives the rotations of a first flywheel 4 and that is capable of generating electric power, and planetary gears (a reversing device) 7 that transmit the torque of the motor 6 to a second flywheel 5 side and drive the rotations of the second flywheel 5 in the direction opposite to the first flywheel 4 in such a way that the inertial torque of the first and second flywheels 4, 5 is counter balanced. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a power storage device capable of storing power by rotating a flywheel, and more particularly to a flywheel type power storage device suitable for in-vehicle use.
[0002]
[Prior art]
In vehicles such as electric vehicles and hybrid cars, an electric power storage device including a flywheel whose rotation speed is controlled by an electric motor capable of generating electric power is sometimes used.
In such a flywheel type power storage device, the electric motor converts the electric energy into the rotational kinetic energy of the wheel by increasing the rotation speed of the flywheel when charging, and stores the electric power when discharging. By functioning as a device, power can be supplied to the outside of the device.
[0003]
By the way, in the flywheel type power storage device as described above, the amount of power that can be stored in the device can be increased by increasing the weight of the flywheel or rotating the flywheel at a higher speed. However, when the amount of electric power is increased in this manner, the inertia torque generated in the wheel increases due to an increase in the weight of the flywheel and the like. For example, a rotating body including the wheel and a main shaft on which the wheel is rotatably provided. The gyro effect is also increased. For this reason, when the rotating body is subjected to disturbance such as vibration during traveling of the vehicle, a large gyro effect is generated, and an undesired force acts greatly on the vehicle body side of the traveling vehicle from the power storage device, and adversely affects the vehicle traveling There was a fear.
[0004]
Therefore, in the conventional device, two flywheels and an electric motor capable of generating electricity are provided on a fixed shaft, and the respective flywheels are rotated by the respective motors in directions opposite to each other, thereby canceling the inertia torque of the flywheels. In order to prevent the occurrence of an adverse effect on the running of the vehicle, there has been provided an apparatus (for example, see Patent Document 1).
Specifically, the two flywheels are formed to have the same moment of inertia by being formed of the same material and having the same shape and dimensions, and each flywheel is substantially the same by a corresponding electric motor. By rotating the flywheel in the reverse direction at a speed, the inertial torque generated by these flywheels is offset, and the above-mentioned adverse effects are prevented from appearing on the vehicle.
[0005]
[Patent Document 1]
JP-A-10-281050 (page 3, FIG. 1)
[0006]
[Problems to be solved by the invention]
However, in the above-described conventional apparatus, two flywheels are driven to rotate using two electric motors, respectively. Therefore, it is necessary to control each of the motors separately, which complicates the control for making the rotation speed control the same. For this reason, it has been difficult to rotate these flywheels at substantially the same speed in opposite directions. Further, since two electric motors are used in this manner, electric parts connected to each motor, for example, electric wiring for functioning as a generator, and switching between the electric motor and the generator connected to this wiring are performed. Required number of electrical parts such as a switching device for switching.
[0007]
In view of the above-described conventional problems, the present invention can reduce the number of necessary electric motors and electric components, and can surely rotate two flywheels in opposite directions to each other. An object is to provide a power storage device.
[0008]
[Means for Solving the Problems]
The present invention is a flywheel type power storage device having first and second flywheels arranged coaxially,
An electric motor capable of generating electric power for rotating and driving the first flywheel;
The rotational force of the electric motor is transmitted to the second flywheel side, and the second flywheel is moved in the opposite direction to the first flywheel so that the inertia torque of the first and second flywheels is offset. And a reversing device for rotationally driving the flywheel.
[0009]
In the flywheel type power storage device configured as described above, when the electric motor rotationally drives the first flywheel, the reversing device uses the rotational force of the motor to cancel the inertia torque. In this way, the second flywheel can be reliably coaxially inverted with respect to the first flywheel. Further, compared to the above-described conventional example in which two electric motors capable of generating electricity are used, the number of necessary motors can be reduced to one, and the number of electric components required for the power storage device can be reduced to half or less.
[0010]
Further, in the flywheel type power storage device, the reversing device may be a planetary gear device.
In this case, the planetary gear device transmits the motor rotational force to the second flywheel by meshing the teeth of the planetary gear and the like included in the device, and the first and second flywheels are provided without providing the wheel motor. The wheels can be reliably rotated mechanically in opposite directions.
[0011]
In the flywheel type power storage device, the reversing device may be a bevel gear device.
In this case, the bevel gear device transmits the motor rotational force to the second flywheel by meshing the teeth of bevel gears and the like included in the device, and the first and second flywheels are provided without providing the wheel motor. The wheels can be reliably rotated mechanically in opposite directions. Also, by providing the bevel gear on, for example, a rotating shaft to which the first and second flywheels are rotatably connected, it is possible to use the same flywheel without forming a tooth portion on these flywheels. Therefore, the number of device parts can be further reduced.
[0012]
Further, in the flywheel type power storage device, the reversing device may be a traction drive device.
In this case, the motor rotational force is transmitted to the second flywheel by the traction force (traction force) of the rollers included in the drive device, and the first and second flywheels are reversed from each other without providing the wheel motor. It can be surely rotated in the direction mechanically.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of a flywheel type power storage device of the present invention will be described with reference to the drawings. In the following description, an example in which a power storage device incorporated in a vehicle such as an electric vehicle is configured will be described.
[0014]
FIG. 1 is a cross-sectional view illustrating a main configuration of a flywheel type power storage device according to an embodiment of the present invention. In the figure, a power storage device 1 of the present embodiment includes a main shaft 3 as a rotary shaft rotatably supported by bearing means (not shown) in a housing 2 fixed to the vehicle side, and integrated with the main shaft 3. A ring-shaped first flywheel 4 is connected to the main shaft 3, and a second flywheel 5 is connected to the main shaft 3 via a planetary gear unit 7 as a reversing device.
[0015]
The power storage device 1 includes a stator winding 6a attached to the housing 2 and a permanent magnet 6b fixed to the main shaft 3, and generates electric power by rotation of the first and second flywheels 4, 5. An electric motor 6 is provided. Further, a switching device (not shown) for switching the motor 6 as an electric motor or a generator is connected to the motor 6, and the power storage device 1 operates the switching device to perform charging and charging. The motor 6 is configured to function as a motor and a generator at the time of discharging. In the electric power storage device 1, at the time of charging, the motor 6 rotates the main shaft 3 and the first flywheel 4 in the R direction in the figure, and the planetary gear unit 7 rotates the second flywheel 5 in the R direction. By rotating the motor 1 in the opposite direction, the device 1 converts the electric power (electric energy) supplied to the motor 6 into rotational kinetic energy of the first and second flywheels 4 and 5 and stores the converted kinetic energy. Can be.
At the time of discharging, the rotational kinetic energy is extracted as electric energy (regenerative power) by the motor 6, and the electric power storage device 1 uses the regenerative electric power for another electric motor such as a drive motor for driving the drive wheels of the vehicle. It can be supplied to equipment.
[0016]
The first flywheel 4 is made of a metal such as iron or a resin such as CFRP or a combination of a metal and a resin. The inner peripheral surface 4 a is press-fitted into the outer peripheral surface of the main shaft 3. Thus, the wheel 4 is connected to the main shaft 3 so as to be integrally rotatable.
The second flywheel 5 is made of, for example, the same material as the first flywheel 4, and is arranged coaxially in the housing 2 so as to face the wheel 4. Further, on the inner peripheral surface side of the wheel 5, a tooth portion 5a is formed which meshes with the planetary gear 7a of the planetary gear device 7, and the rotational force of the motor 6 is generated by meshing between the gear 7a and the tooth portion 5a. Is transmitted.
The first and second flywheels 4 and 5 are configured such that their moments of inertia are substantially the same. Specifically, the first and second flywheels 4 and 5 are formed to have the same outer diameter dimension and axial dimension, but the formation of the tooth portion 5a of the second flywheel 5 is described. According to the weight reduction associated with the above, a slit or the like is provided in the inner diameter portion of the first flywheel 4 to reduce the weight, thereby achieving the same moment of inertia.
[0017]
The planetary gear device 7 includes three planetary gears 7a circumferentially arranged at intervals of, for example, 120 degrees with respect to the axis center of the main shaft 3 and the housing 2 in a state where each of the planetary gears 7a is rotatably supported. And a mounting member 7b to be mounted. Further, in this planetary gear device 7, the tip of the main shaft 3 is used as a sun gear, and the tip of the main shaft 3 is splined to form teeth 3a that mesh with the respective planetary gears 7a. The sun gear that rotates integrally with the main shaft is constituted by the tip of the main shaft. In the planetary gear device 7, when the main shaft 3 is driven to rotate by the electric motor 6, each planetary gear 7a rotates in a state where the planetary gear 7a is prevented from revolving by the mounting member 7b, and the meshing portion with the tooth portion 5a is formed. By transmitting the motor rotational force to the second flywheel 5 via this, the wheel 5 is rotationally driven in a direction opposite to the R direction in the drawing and at substantially the same speed as the first flywheel 4. As a result, the first and second flywheels 4, 5 having substantially the same moment of inertia are rotated in directions opposite to each other in a state in which the inertia torque generated by the rotation is canceled.
In addition to the above description, a configuration using a sun gear having a through-hole that is press-fitted into the outer peripheral surface of the main shaft 3 may be used.
[0018]
In the flywheel type power storage device 1 of the present embodiment configured as described above, when the first flywheel 4 is rotated by the electric motor 6 in the R direction in FIG. The rotational force of the motor 6 is transmitted by meshing the tooth portion 5a formed on the inner peripheral surface side with the planetary gear 7a of the planetary gear device (reversing device) 7, so that the first flywheel 4 and the first flywheel 4 are substantially transmitted. Are driven to rotate at the same speed in the opposite direction. As a result, in the power storage device 1, the inertia torques generated in the first and second flywheels 4 and 5 cancel each other, and each of the inertia torques causes an undesired force from the device to the vehicle body side. Can be prevented from being transmitted.
[0019]
Further, in the present embodiment, since the electric motor 6 is commonly used as a drive source for rotationally driving the first and second flywheels 4 and 5, electric components of the power storage device 1, for example, the switching device There is no need to provide a plurality of electric components such as a control device for controlling the rotation speed of the motor 6, and the number of electric components can be reduced to half or less as compared with the above-mentioned conventional product using two electric motors. A small and energy-saving power storage device can be easily configured. In addition, since the planetary gear device 7 mechanically reverses the second flywheel 5 mechanically at substantially the same speed as the first flywheel 4, it is possible to minimize problems caused by troubles in the electric components. In this state, the inertia torque of the flywheels 4 and 5 can be surely canceled. Specifically, for example, even when the supply voltage to the electric motor 6 decreases, the planetary gear device 7 lowers the rotation speed of the second flywheel 5 according to the decrease in the motor rotational force accompanying the voltage decrease. , The rotational speed of the first flywheel 4 can be substantially equalized, and the inertia torque can be surely canceled.
[0020]
FIG. 2 is a cross-sectional view illustrating a main configuration of a flywheel power storage device according to another embodiment. In FIG. 2, the main difference between this embodiment and the embodiment shown in FIG. 1 is that a bevel gear device 17 is provided instead of the planetary gear device 7, and the second flywheel 14b is provided by this device 17. The point is that the first flywheel 14a is driven to rotate in the opposite direction at substantially the same speed.
As shown in FIG. 2, in the present embodiment, the main shaft 13 as a rotating shaft rotatable inside the housing 2 is integrated with the wheel 14a by press-fitting the inner peripheral surface 14a1 of the first flywheel 14a. And a second shaft member 13b integrally connected to the inner peripheral surface 14b1 of the second flywheel 14b by press-fitting the wheel 14b. The electric motor 6 capable of generating power is attached to the first shaft member 13a. In addition, a bevel gear device 17 as the reversing device is provided between the first and second shaft members 13a and 13b.
The first and second flywheels 14a and 14b are formed, for example, using the same material and have the same shape and dimensions so that the moments of inertia are substantially equal.
[0021]
The bevel gear device 17 is attached to each end of the first and second shaft members 13a and 13b, and connected to the bevel gears 17a and 17b facing each other and the bevel gears 17a and 17b. At the same time, four bevel pinion gears 17c are arranged at equal intervals, for example, at 90 degrees with respect to the center of the main shaft 13, and one end is fixed to the projection 2a in the housing 2 and the other end is fixed to the projection 2a. A pin member 17d that rotatably supports the above bevel pinion gears 17c. In this bevel gear device 17, when the electric motor 6 rotates the first shaft member 13a and the first flywheel 14a in the R1 direction in the drawing, the bevel gear 17a provided on the first shaft member 13a side becomes While rotating in the same direction, the bevel gear 17a rotates the above bevel pinion gears 17c in which the teeth mesh with each other in the direction R3 in FIG. Further, with the rotation of the bevel pinion gears 17c, the bevel gears 17b in which the respective bevel pinion gears 17c and the teeth mesh with each other rotate in the R2 direction in the drawing, and the second shaft member 13b and the second The flywheel 14b is rotationally driven in the same R2 direction and at substantially the same rotational speed as the first flywheel 14a.
[0022]
In the present embodiment configured as described above, the bevel gear device (reversing device) 17 mechanically moves the second flywheel 14b in the opposite direction to the first flywheel 14a by using the rotational force of the electric motor 6. , The inertial torques of the first and second flywheels 14a and 14b can be offset in a state where the number of necessary electric components is reduced, as in the above-described embodiment. The effects of the above embodiment can be obtained similarly. Furthermore, in the present embodiment, the first and second flywheels 14a and 14b are formed in the same shape and the same size using the same material. The number of parts can be further reduced, and there is no need to perform a tooth forming process on the second flywheel.
[0023]
FIG. 3 is a cross-sectional view illustrating a main configuration of a flywheel power storage device according to another embodiment. In FIG. 3, the main difference between this embodiment and the embodiment shown in FIG. 2 is that a traction drive device 27 is provided instead of the bevel gear device 17, and the second flywheel 24b is provided by this device 27. The point is that the first flywheel 24a is rotationally driven in the opposite direction.
As shown in FIG. 3, in the present embodiment, the main shaft 23 as a rotation shaft rotatable in the housing 2 is integrated with the first flywheel 24 a by press-fitting the inner peripheral surface 24 a 1 of the flywheel 24 a. And a second shaft member 23b integrally connected to the inner peripheral surface 24b1 of the second flywheel 24b by press-fitting the wheel 24b. The electric motor 6 capable of generating electric power is attached to the first shaft member 23a. Further, a traction drive device 27 as the reversing device is provided between the first and second shaft members 23a and 23b.
Further, the first and second flywheels 24a and 24b are configured such that their moments of inertia are substantially the same. More specifically, the first and second flywheels 24a and 24b are formed to have the same external dimensions and axial dimensions, but the traction drive device 27 of the second flywheel 24b is used. In accordance with the deceleration (transmission loss), a slit or the like is provided in the inner diameter portion of the first flywheel 24a to equalize the moment of inertia.
[0024]
The traction drive device 27 is attached to one end of each of the first and second shaft members 23a and 23b, and the traction rollers 27a and 27b are disposed to face each other. And four traction rollers 27c circumferentially arranged at an interval of, for example, 90 degrees with respect to the axis center of the main shaft 23, and one end side is fixed to the protrusion 2a in the housing 2 and the other end is And a pin member 27d rotatably supporting the traction roller 27c on the side. In the traction drive device 27, when the electric motor 6 rotates the first shaft member 23a and the first flywheel 24a in the R1 direction in the figure, the traction roller 27a provided on the first shaft member 23a side is turned on. In addition to the rotation in the same direction, the respective traction rollers 27c roll on the rollers 27a in accordance with the rotation of the rollers 27a and rotate in the R3 direction in FIG. Further, with the rotation of each traction roller 27c, the traction roller 27b rolls on each roller 27c and rotates in the R2 direction in the figure, and the second shaft member 23b and the second flywheel 24b are rotated. The first flywheel 24a is driven to rotate in the same R2 direction at substantially the same rotational speed as the first flywheel 24a.
[0025]
In the present embodiment configured as described above, the traction drive device (reversing device) 27 mechanically moves the second flywheel 24b in the opposite direction to the first flywheel 24a by using the rotational force of the electric motor 6. , The inertial torques of the first and second flywheels 24a, 24b can be offset in a state in which the number of necessary electric components is reduced, as in the above-described embodiment. The effect of the embodiment shown in FIG. 2 can be obtained similarly. In addition, unlike the embodiment shown in FIG. 1, there is no need to carry out a tooth forming process or the like on the second flywheel.
[0026]
In the above description, a case has been described in which an electric power storage device incorporated in a vehicle is configured. However, the present invention provides a first flywheel that is rotated in one direction by an electric motor capable of generating electric power. Any device may be used as long as the device drives the second flywheel to rotate in the other direction by the rotational force of the motor, and rotates the wheels in opposite directions so that the inertia torque generated by these flywheels cancels out. The present invention can be applied to various power storage devices used for other transportation means other than vehicles, such as railways, and electric facilities such as factories.
Further, in the description of each of the above embodiments, a case has been described in which the inertia torques of the first and second flywheels are mutually canceled to completely cancel each other. What is necessary is just to reverse the rotation, and it is also possible to reduce the inertia torque of these wheels.
Further, in the description of each of the above-described embodiments, the configuration having the ring-shaped first and second flywheels arranged in the upper and lower stages in the axial direction is described. However, the present invention is not limited to the above-described one. For example, instead of the first flywheel 4, two wheels having a moment of inertia of の of the One flywheel may be configured.
[0027]
Also, in the embodiment shown in FIGS. 1 and 3, the first flywheel 4; 24b is designed so that the moment of inertia of the second flywheel 5; 24b is substantially the same as that of the first flywheel 4; 24a. 24a is provided with a slit, but the present invention is not limited to this. For example, the planetary gear device 7 or the traction drive device 27 increases the rotational speed of the second flywheel 5; By making it larger than that of the first flywheel 4, the inertia torque of the first and second flywheels having the same axial dimension may be offset or the first and second wheels may be offset. The inertia torque may be canceled by changing the outer diameter dimension and adjusting the wheel weight, or another method may be appropriately adopted.
In the embodiment shown in FIG. 2, the main shaft 13 is divided into first and second shaft members 13a and 13b, and bevel gears 17a and 17b are provided at the distal ends of the shaft members 13a and 13b. Although the device 17 has been described, the bevel gear device is not limited to this, and is connected to a plurality of bevel pinion gears provided on the housing 2 side and has a ring-like shape having a through hole through which a main shaft is inserted. A configuration in which bevel gears are attached to the opposing surfaces of the first and second flywheels may be used. In the case of such a configuration, it is not necessary to divide the main shaft into two shaft members.
[0028]
The bearing means in each of the embodiments shown in FIGS. 1 to 3 is constituted by a rolling bearing or a magnetic bearing, and can support a rotating body including a main shaft in a state where bearing loss during high-speed rotation is minimized. It has become. When a magnetic bearing is used, a touch-down bearing used only when an emergency occurs is included. In the case where an abnormality occurs in the magnetic bearing, for example, the rotating body rotating at a high speed rotates the housing 2. It prevents contact with the inner surface and the like, and prevents damage to the rotating body and the like.
Further, in each of the embodiments, the case where the electric motor 6 is constituted by the synchronous motor having the permanent magnet 6b provided on the main shaft has been described. .
In the embodiment shown in FIG. 2 or FIG. 3, the reversing device (bevel gear device or traction drive device) is applied to an inner rotor type in which the first and second flywheels rotate integrally with a main shaft as a rotation shaft. Although the case has been described, for example, by using the above-mentioned ring-shaped bevel gears or rollers, an outer rotor type in which the first and second flywheels are rotatably arranged with a predetermined gap with respect to the fixed shaft is provided. A gear device or a traction drive device can also be applied.
The reversing device of the present invention is not limited to the one described in the above embodiment.
[0029]
【The invention's effect】
According to the flywheel type power storage device of the present invention, the first and second flywheels are rotationally driven by one electric motor and one reversing device so as to cancel the inertia torque. It is possible to reduce the number of rotations and to surely rotate the flywheels in directions opposite to each other.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a main configuration of a flywheel type power storage device according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view illustrating a configuration of a main part of a flywheel power storage device according to another embodiment.
FIG. 3 is a cross-sectional view illustrating a configuration of a main part of a flywheel power storage device according to another embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Flywheel type electric power storage device 4, 14a, 24a 1st flywheel 5, 14b, 24b 2nd flywheel 6 (electric power generation) electric motor 7 Planetary gear device (reversing device)
17 Bevel gear device (reversing device)
27 Traction drive device (reversing device)

Claims (4)

A flywheel type power storage device having first and second flywheels arranged coaxially,
An electric motor capable of generating electric power for rotating and driving the first flywheel;
The rotational force of the electric motor is transmitted to the second flywheel side, and the second flywheel is moved in the opposite direction to the first flywheel so that the inertia torque of the first and second flywheels is offset. A flywheel type power storage device comprising: a reversing device for driving a flywheel to rotate. The flywheel type power storage device according to claim 1, wherein the reversing device is a planetary gear device. The flywheel power storage device according to claim 1, wherein the reversing device is a bevel gear device. The flywheel power storage device according to claim 1, wherein the reversing device is a traction drive device.

Images