The present invention relates to a power equipment apparatus having a flywheel apparatus.
Some conventional vehicles are equipped with an internal combustion engine having a battery-powered electric start system. In order to facilitate starting of the engine in cold weather conditions, the battery typically comprises a lead-acid type battery which is capable of providing the significant instantaneous power (typically identified in terms of “cold-cranking amps”) required to start the engine in cold weather conditions. However, the battery is typically relatively large and heavy, and its presence upon a vehicle can accordingly present engineering challenges, design inefficiencies, and adverse effects upon the vehicle.
In accordance with one embodiment, a power equipment apparatus comprises an engine, an electric starter motor, a starter switch, a battery, a flywheel assembly, first and second power regulators, and a controller. The engine comprises a crankshaft. The electric starter motor is operatively coupled with the crankshaft. The starter switch is configured for selective actuation by an operator. The flywheel assembly comprises a rotor and a stator. The stator comprises a low voltage coil and a high voltage coil. The first power regulator is coupled with each of the battery and the low voltage coil. The first power regulator is configured to regulate power transfer between the battery and the low voltage coil in response to a first control signal. The second power regulator is coupled with each of the high voltage coil and the electric starter motor. The second power regulator is configured to regulate power transfer between the high voltage coil and the electric starter motor in response to a second control signal. The controller is coupled with each of the battery, the starter switch, the first power regulator, and the second power regulator. The controller is configured to generate the first control signal and the second control signal.
In accordance with another embodiment, a saddle-type vehicle comprises a frame, a seat, an engine, an electric starter motor, a starter switch, a battery, a flywheel assembly, first and second power regulators, and a controller. The seat is attached to the frame and is configured to support an operator. The engine comprises a crankshaft and is attached to the frame. The electric starter motor is operatively coupled with the crankshaft. The starter switch is configured for selective actuation by an operator. The flywheel assembly comprises a rotor and a stator. The stator comprises a low voltage coil and a high voltage coil. The first power regulator is coupled with each of the battery and the low voltage coil. The first power regulator is configured to regulate power transfer between the battery and the low voltage coil in response to a first control signal. The second power regulator is coupled with each of the high voltage coil and the electric starter motor. The second power regulator is configured to regulate power transfer between the high voltage coil and the electric starter motor in response to a second control signal. The controller is coupled with each of the battery, the starter switch, the first power regulator, and the second power regulator. The controller is configured to generate the first control signal and the second control signal. All power transferred between the battery and the electric starter motor passes through the flywheel assembly. The flywheel assembly is configured to selectively receive power from the battery and store the power received from the battery. The flywheel assembly is further configured to selectively dispense the power received from the battery to the electric starter motor to facilitate starting of the engine.
In accordance with yet another embodiment, a power equipment apparatus comprises an engine, a starter switch, a battery, a flywheel assembly, a power regulator, and a controller. The engine comprises a crankshaft. The starter switch is configured for selective actuation by an operator. The flywheel assembly comprises a rotor and a stator. The rotor is rotationally coupled with the crankshaft. The power regulator is coupled with each of the battery and the stator. The power regulator is configured to regulate power transfer between the battery and the stator in response to a control signal. The controller is coupled with each of the battery, the starter switch, and the power regulator. The controller is configured to generate the control signal.
While the specification concludes with claims particularly pointing out and distinctly claiming the present invention, it is believed that the same will be better understood from the following description taken in conjunction with the accompanying drawings in which:
Certain embodiments are hereinafter described in detail in connection with the views and examples of
An example of a motorcycle 10 in accordance with one embodiment is depicted in
The motorcycle 10 is shown in
The motorcycle 10 also includes an electric starter motor 26 as generally shown in
In the embodiment of
A power equipment apparatus can include a battery which is configured to store energy for use to effectuate operation of a starter motor and resultant cranking and starting of an associated engine. In one embodiment, the battery can have a nominal voltage of about 12 V.D.C., as is typical of many conventional automobile batteries. By providing a battery having a nominal voltage of about 12 V.D.C., it will be appreciated that the battery can often readily interface other existing vehicular electrical systems, as many such systems are designed to operate at this voltage. However, it will be appreciated that a battery can have any of a variety of other suitable voltages such as, for example, 6 V.D.C. and/or 24 V.D.C., and/or that a vehicle can comprise more than one battery which can be connected in series and/or parallel.
In one embodiment, a battery can comprise a lead-acid type battery. However, in accordance with one embodiment, the battery might not comprise a lead-acid battery. For example, in one particular embodiment, the battery can comprise a lithium-ion battery (such as, for example, a lithium-ion thin film battery). In other embodiments, the battery can comprise a nickel-cadmium battery, a nickel metal hydride battery, or any of a variety of other suitable types of battery. In one embodiment, the battery can be relatively compact and lightweight and, as described further below, need not be capable of producing as much instantaneous power (typically identified in terms of “cold-cranking amps”) as would be possible from a conventional lead-acid type battery.
In order to start the engine 14, an operator of the motorcycle 10 can actuate a starter switch 28 as shown in
In addition to being coupled with the starter switch 28, the controller 56 can also be coupled (via wires, wirelessly, optically, or otherwise) to other features or components present upon the power equipment apparatus. As illustrated in
The heater module 58 can be associated with the battery 30 and can be configured to warm or pre-heat the battery 30, such as during cold weather conditions, in response to a preheat signal from the controller 56. In one embodiment, the heater module 58 can comprise heating coils which receive power from the battery 30 as directed by the controller 56. The vacuum pump 60 can be coupled with a flywheel assembly 40 and can be configured, as when directed by the controller 56, to create a vacuum with a housing of the flywheel assembly 40 in response to a vacuum signal from the controller 56, as described in further detail below.
The controller 56 can also be coupled with the engine 14, as generally depicted in
The controller 56 can also be coupled with each of the battery 30 and the flywheel assembly 40 and can be configured to monitor the state of charge of each of these devices. For example, the controller 56 can monitor the voltage of the battery 30, and perhaps also the current being drawn from the battery 30, to assess the state of charge of the battery 30. As another example, the controller 56 can monitor the rotational speed of the rotor 42 of the flywheel assembly 40 in order that the controller 56 can approximate the amount of energy stored in the flywheel assembly 40 at any given time.
The controller 56 is also shown in
The flywheel assembly 40 is shown in
The flywheel assembly 40 can be positioned at any of a variety of suitable locations upon the motorcycle 10. For example, in one embodiment as shown generally in
In the example of
By implementation of the flywheel assembly 40 in this arrangement, it will be appreciated that the battery 30 can have a peak power producing capacity which is less than the power required of the electric starter motor 26 to rotate the crankshaft 24 (at an ambient temperature that falls within a range normally encountered by the engine 14). In other words, the battery 30 need not be capable of itself providing ample instantaneous power to facilitate cranking of the engine 14, but rather can provide that same amount of power over an extended period of time for storage in the flywheel assembly 40. The flywheel assembly 40 can then provide this power to the electric starter motor 26 over a relatively short period of time to facilitate cranking of the engine 14. In one embodiment, in such a configuration, multiple flywheel assemblies (e.g., each like flywheel assembly 40), can be electrically connected in parallel such as to provide increased power capacity (for engine starting) and/or for redundancy purposes (in the event of failure of one of the flywheel assemblies).
By sending suitable control signals to the power regulator 50, it will be appreciated that the controller 56 can vary the rate of power transfer from the battery 30 to the flywheel assembly 40, and can accordingly vary the rate at which the rotor 42 of the flywheel assembly 40 is accelerated, and the resultant rate at which the flywheel assembly 40 is charged with power. In one embodiment, the controller 56 can be configured to facilitate variation of the rate of power transfer between the battery 30 and the flywheel assembly 40 in response to its detection of at least one of ambient temperature (e.g., as can be determined by engine oil or coolant temperature) and charge of the battery 30. For example, at low temperatures or low states of charge of the battery 30, the controller 56 can cause acceleration of the rotor 42, and thus charging of the flywheel assembly 40, at a prolonged rate as compared with that which may be achievable at higher temperatures and/or states of charge of the battery 30. In this manner, the controller 56 can prevent draining of excessive current from the battery 30, and resultant damage to the battery 30.
It will also be appreciated that, by sending suitable control signals to the power regulator 52, the controller 56 can vary the rate of power transfer between the flywheel assembly 40 and the electric starter motor 26. By varying the amount of power provided to the electric starter motor 26, the controller 56 can adjust the speed and/or torque at which the electric starter motor 26 cranks the engine 14. Such adjustment can enable the controller 56 to avoid having the flywheel assembly 40 deliver more power to the electric starter motor 26 than is required of the electric starter motor 26 to crank the engine 14, and thus avoids wasting power. Also, certain other benefits, such as potentially in the area of emissions reduction, can be achieved by facilitating adjustability of engine cranking speed.
Also, by sending suitable control signals to the power regulator 50, the controller 56 can vary the rate of power transfer from the flywheel assembly 40 to the battery 30, and can accordingly vary the rate at which the battery 30 is charged by the flywheel assembly 40. Also, by sending suitable control signals to the power regulator 52, the controller 56 can vary the rate of power transfer from the electric starter motor 26 to the flywheel assembly 40, and can accordingly vary the rate at which the rotor 42 of the flywheel assembly 40 is accelerated under power from the electric starter motor 26, and is thus charged.
Once the flywheel assembly “charges up” to a predetermined energy limit, and once an engine start signal has been generated (e.g., as a result of actuation of the starter switch 28 or a remote start signal from a key fob), the controller 56 can send a control signal to the power regulator 52 to facilitate release of the power from the flywheel assembly 40 to the electric starter motor 26, and thus to facilitate starting of the engine 14. During this release of power, the controller 56 can also send a control signal to the power regulator 50 to facilitate continued provision of power from the battery 30 into the flywheel assembly 40 (e.g., at a level consistent with that provided by the battery 30 to the flywheel assembly 40 during “charging” of the flywheel assembly 40 prior to the cranking event). The predetermined energy limit of the flywheel assembly 40 can vary depending upon temperature and can range, for example, between 5 kJ and 20 kJ. At high temperatures, the predetermined energy limit may be lower than at low temperatures, and thus the charging time for the flywheel assembly may be reduced to improve customer convenience.
In one embodiment, since it takes time (e.g., 30-60 seconds) to facilitate charging of the flywheel assembly 40 from the battery 30 (e.g., at a current of about 60-80 A), a power equipment apparatus might be configured to begin this charging process before an operator actuates the starter switch or otherwise generates an engine start signal. For example, the controller 56 can initiate this charging process upon its receipt of a charge initiation signal. The charge initiation signal can be generated by or in response to actuation of an occupancy switch (e.g., 32 in
Accordingly, it will be appreciated that the flywheel assembly 40 of
Creation of a sufficient vacuum within a housing of the flywheel assembly 40 can facilitate improved efficiency and reduced friction losses during high speed rotation of the rotor 42 of the flywheel assembly 40. In one embodiment, the vacuum pump 60 can comprise a turbo-vacuum pump, though it will be appreciated that the vacuum pump 60 can be provided in any of a variety of suitable configurations. Once the vacuum pump 60 creates a vacuum within the flywheel assembly 40, the vacuum may be maintained for an extended period of time even though the vacuum pump 60 is no longer running depending, for example, upon the quality of seal present within the flywheel assembly 40. It will be appreciated that the controller 56 can be configured to selectively operate the vacuum pump 60 during operation of the engine 14 in order that the battery 30 can be recharged after operating the vacuum pump 60 and prior to stopping operation of the engine 14. The controller 56 can monitor the state of vacuum within the flywheel assembly 40 and, if the state of vacuum is insufficient, the controller 56 can cause the vacuum pump 60 to operate by withdrawing power from the battery 30 to create a sufficient vacuum within the flywheel assembly 40.
By providing a power equipment apparatus with a flywheel assembly such as described above, it will be appreciated that the power equipment apparatus can be provided with a smaller and lighter battery than would otherwise be required, as the battery need not by itself produce the large amount of power as required in real time by the electric starter motor during cranking of the engine. In fact, in accordance with one embodiment, battery weight could be reduced by up to 30%. A reduction in battery size and weight can result in improved performance and efficiency of an associated power equipment apparatus. In addition, this arrangement can improve cranking success, particularly at cold temperatures, as it can help to ensure the presence of a reliable and adequate power reservoir (i.e., within the flywheel assembly) prior to initiating cranking of the engine. Also, as the battery is never required to provide the full amount of power in real time as required by the electric starter motor, it will be appreciated that the useful life of the battery can be significant, perhaps as long as 10-12 years, thus requiring infrequent replacement of the battery.
When a battery has a low state of charge, the battery can still charge a flywheel assembly, albeit perhaps over a more extended period of time (e.g., exceeding 1-2 minutes). This would potentially enable the power equipment apparatus to be started in particularly cold situations in which conventional vehicles would be difficult or impossible to start from battery power alone. In this situation, if an operator uses a remote start function, the flywheel assembly can charge for 1-2 minutes from the battery before providing power to the electric starter motor, and before the operator even approaches the power equipment apparatus. In this situation, the operator is only minimally inconvenienced, the electric starter motor receives the power necessary to start the engine, and the battery is not exposed to a high current event, thus maximizing battery longevity.
It will also be appreciated that a vehicle in accordance with one embodiment can have improved fuel efficiency as compared to conventional vehicles. For example, in the embodiment of
The clutch 264 can be coupled with the controller 256 and can configured to selectively decouple the rotor 242 from the crankshaft 224 in response to a control signal from the controller 256. In this configuration, when the engine 214 is not operating, the clutch 264 is disengaged, and it becomes desirable to start the engine 214, the controller can facilitate provision of power from the battery 230, through the power regulator 250, and to the flywheel assembly 240 to facilitate acceleration of the rotor 242 and resultant charging of the flywheel assembly 240. The controller 256 can then engage the clutch 264 to facilitate coupling of the rotor 242 to the crankshaft 224 (e.g., through gear reduction 266, gear 227, and flywheel 225), and resultant cranking of the engine 214. During operation of the engine 214, with the clutch 264 engaged, power can be generated by the flywheel assembly 240 and provided to the battery 230 through the power regulator 250 to facilitate charging of the battery 230. It will be appreciated that, in one embodiment, the battery 230 can continue providing power to the flywheel assembly 240 even during the cranking of the engine 214 by the flywheel assembly 240.
The foregoing description of embodiments and examples of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the forms described. Numerous modifications are possible in light of the above teachings. Some of those modifications have been discussed and others will be understood by those skilled in the art. The embodiments were chosen and described in order to best illustrate the principles of the invention and various embodiments as are suited to the particular use contemplated. The scope of the invention is, of course, not limited to the examples or embodiments set forth herein, but can be employed in any number of applications and equivalent devices by those of ordinary skill in the art. Rather it is hereby intended the scope of the invention be defined by the claims appended hereto.