Patent Application
20160116021
The present disclosure relates to a flywheel, and more specifically, to the flywheel including weights.
A flywheel is used for storage of energy in variety of machines such as, but not limited to vehicles. The flywheel can be used at different locations in a vehicle for receiving or supplying energy in a variety of scenarios. As generally known in the art, a flywheel is coupled with a crankshaft of an internal combustion engine. Energy is supplied to the flywheel during a power stroke of an engine through the crankshaft, and energy is received by the crankshaft from the flywheel during the remaining strokes of the engine. This arrangement ensures that a more constant angular speed of the crankshaft is maintained during different strokes of an internal combustion engine and a more constant torque is provided to a drive assembly of the vehicle.
Apart from the aforementioned, a flywheel can also be placed remotely from the crankshaft of an engine, and connected through gears to the drive shaft of the vehicle for storing and releasing of energy. In such a flywheel, it is required that the speed of the flywheel should match the speed of the gears attached to the drive shaft during coupling. Typically, an additional assembly is required to match the speed of the flywheel to the speed of the gears. This additional assembly makes the overall system more bulky and energy consuming. Another technique to match the speed of the flywheel is to use a flywheel which is able to vary its inertia. Such flywheels can regulate their speed without the need of any additional transmission assemblies. These flywheels include a mechanism to vary the distance of additional weights from the centre of the flywheel to change the inertia. However, such flywheels are not able to store enough energy due to instability of additional weights at high angular velocity of the flywheel. Hence, an improved flywheel is required that eliminates the need for an additional transmission assembly for varying its speed and also is stable at high angular velocities.
United States Publication Number 7044022 discloses a variable inertia flywheel apparatus which is connected to a crankshaft of an engine. It describes that a flywheel having variable inertia, a first and a second guide grooves respectively formed at a body of the flywheel and a rotatable member. A movable weight is disposed at the overlapping position, and the rotatable member rotates relatively to the body by hydraulic pressure. However, this reference does not disclose employing the flywheel remotely from the crankshaft for storing energy and any method for stabilizing the flywheel at high angular velocities. Hence, an improved flywheel structure is required that balances the forces generated by additional weights in a variable flywheel.
In one aspect of the present disclosure, a flywheel is provided. The flywheel including a rim having a circular shape, a first hub disposed coaxially within the rim, and elongated along a first axis of the rim, and at least two spokes. Each of the at least two spokes having a first end coupled to the rim, and a second end coupled to the first hub. Further, the flywheel includes a second hub disposed coaxially with the rim, and adapted to slide on an outer surface of the first hub along the first axis of the rim. The second hub has at least one guiding member. The at least one guiding member including a slot. The flywheel includes at least two assemblies corresponding to the at least two spokes, such that one of the at least two assemblies is coupled to one of the at least two spokes. Each of the at least two assemblies including a first weight disposed adjacent to the first hub, and disposed coaxially with the one of the at least two spokes. The first weight is adapted to slide along a length of the one of the at least two spokes, and having at least one protruding member. The at least one protruding member is adapted to slide along the slot of the at least one guiding member. A spring member is disposed adjacent to the first weight along a radial direction, and the spring member is disposed coaxially with the first weight. The spring member is adapted to apply a spring force to the first weight to oppose the sliding of the first weight along the length of the one of the at least two spokes in the radial direction. A support member is disposed adjacent to the spring member along the radial direction, and the support member is disposed coaxially with the spring member. The support member is adapted to slide along the length of the one of the at least two spokes. A weight assembly including at least one second weight which is disposed adjacent to the support member along the radial direction. The at least one second weight having a cam shape, and is adapted to rotate about a second axis of the at least one second weight. The at least one second weight is adapted to compress the spring member above a predetermined angular velocity of the flywheel. The weight assembly including a mount member which is disposed coaxially with the support member, and is coupled to the at least one second weight. The mount member is adapted to slide along the length of the one of the at least two spokes. An actuator is coupled to the second hub, and is adapted to move the second hub along the first axis of the rim.
Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.
Referring to
The flywheel 22 is connected to a first gear 36 through a shaft 38. The first gear 36 is further coupled to a second gear 40. In an embodiment, the first gear 36 and the second gear 40 have a fixed gear ratio. The second gear 40 is coupled to the first drive shaft 32. The controller 18 is coupled to the engine 12, the first clutch 14, the transmission module 16 and the flywheel 22. The controller 18 is adapted to control electrical systems or subsystems of the vehicle such as, but not limited to, the first clutch 14. A second clutch 42 is adapted to couple or decouple the flywheel 22 to the first gear 36. When the vehicle moves and the flywheel 22 is coupled to the first gear 36 through the second clutch 42, the kinetic energy of the vehicle is stored or recovered from the flywheel 22, depending on a speed of the flywheel 22 with respect to speed of the first gear 36. The flywheel 22 is adapted to receive the kinetic energy from the first gear 36 of the powertrain 10, when the speed of the first gear 36 is greater than the speed of the flywheel 22. The flywheel 22 is adapted to transfer the kinetic energy to the first gear 36, when the speed of the first gear 36 is less than the speed of the flywheel 22. The flywheel 22 is adapted to receive the kinetic energy from the first gear 36, when the speed of the first gear 36 greater than the speed of the flywheel 22. The flywheel 22 is decoupled from the first gear 36 by the second clutch 42, when the flywheel 22 is not required.
Referring to
The assembly 52 includes a first weight 68, a spring member 70, a support member 72 and a weight assembly 74. The first weight 68 is disposed adjacent to the first hub 46 in a radial direction away from the first axis 2-2′ and aligned coaxially with the spoke 50. The first weight 68 is adapted to slide along a length of the spoke 50. The first weight 68 includes at least one protruding member 76 on each side of the first weight 68. In an embodiment, the first weight 68 includes two protruding members 76. The protruding member 76 slides along the slot 66 to enable movement of the first weight 68. The first weight 68 has a predetermined weight. The spring member 70 is aligned adjacent to the first weight 68 in a radial direction away from the first axis 2-2′ of the rim 44. The spring member 70 is also aligned coaxially with the first weight 68. The spring member 70 is a compression spring of a high spring rate. The support member 72 is disposed adjacent to the spring member 70 in the radial direction away from the first axis 2-2′ of the rim 44 and aligned coaxially with the spring member 70. The support member 72 is adapted to slide along the length of the spoke 50.
The weight assembly 74 includes at least one second weight 78 and a mount member 80. The second weight 78 is disposed adjacent to the support member 72 in a radial direction away from the first axis 2-2′ of the rim 44. The second weight 78 has a cam shape and a predetermined weight. The second weight 78 is adapted to rotate about a second axis 3-3′. The mount member 80 is aligned coaxially with the support member 72 and is adapted to slide along the length of the spoke 50. The second weight 78 is coupled via the mount member 80.
Referring to
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The speed dependant stresses are counterbalanced by the support member 72 and the weight assembly 74. When the flywheel 22 rotates above a predetermined angular velocity, the second weight 78 of the weight assembly 74 also rotates about the second axis 3-3′ pushing the support member 72 along the radial direction towards the first axis 2-2′ of the rim 44. Since the support member 72 is disposed adjacent to the spring member 70, the support member 72 compresses the spring member 70 that generates the spring force to counterbalance the speed dependent stresses in the first weight 68. In effect, the speed dependent stresses are counterbalanced by the force generated by the weight assembly 74 on the spring member 70.
It should be noted that the actuator 54 may be hydraulically controlled, mechanically controlled or pneumatically controlled without departing from meaning and scope of the disclosure. It should be further noted that the flywheel 22 may include one or more spokes 50, assemblies 52 and protruding members 76 depending on the design requirements of the flywheel 22 without departing from the meaning and scope of the disclosure.
The present disclosure provides the flywheel 22. The inertia of the flywheel 22 is varied by moving the first weight 68 along the length of the spoke 50. When the first weight 68 moves towards the rim 44, the inertia of the flywheel 22 increases and when the first weight 68 moves away from the rim 44, the inertia of the flywheel 22 decreases. For the flywheel 22 with a constant amount of energy, decreasing its inertia increases its speed and increasing its inertia decreases its speed. Since the flywheel 22 is adapted to change its speed by varying its inertia, the flywheel 22 is self sufficient to match its speed around that of the first gear 36, in order to transmit or receive energy to/from the powertrain 10. Thus, the flywheel 22 eliminates the use of an additional transmission assembly in order to transmit energy between the flywheel 22 and the powertrain 10.
Also, the flywheel 22 includes a mechanism to counterbalance the position dependent stresses and the speed dependent stresses generated on the first weight 68 that destabilize the first weight 68 when the flywheel 22 rotates at higher rotational speed. To counterbalance the position dependent stresses, the spring member 70 is adapted to apply a spring force to the first weight 68 along the radial direction. To counterbalance the speed dependent stresses, the second weight 78 rotates about the second axis 3-3′ pushing the support member 72 along the length of the spoke 50. The support member 72 compresses the spring member 70 that applies a spring force to the first weight 68 along the radial direction and counters the speed dependant stresses.
While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.
