Not Applicable
Not Applicable
The present invention relates to electrical generators, and more specifically to generators using human muscle energy or gravitational potential energy to charge battery-powered electronic devices via universal serial bus (USB).
The first electrical generator was created in 1831 by Michael Faraday and was powered by human muscle energy. Generators powered by the action of gravity on water were first created in the 1880s. Innovation to better harness these two sources of electricity, human muscles and gravity, has continued, but each has progressed along its own separate pathway. Recent technological developments have created opportunity not only for accelerated progress along the separate pathways of human- and gravity-powered electricity, but for the pathways to be combined.
The following is a tabulation of relevant prior art
With the emergence of USB fast-charging standards such as USB power delivery (USB-PD), introduced in 2012, and Qualcomm QuickCharge (QC), introduced in 2013, charging devices via USB at up to 100 watts has become possible.
Despite these dramatic improvements to charging standards, which have in turn led to the development of higher power wall and car chargers for portable electronic devices now making their way into the market, human- and gravity-powered electricity generators have lagged behind. Of the gravity-powered generators in the prior art, none provide electronic device charging functionality via a USB interface. Of the human-powered generators in the prior art, some do provide electronic device charging functionality via a USB interface (U.S. Pat. Nos. 8,988,038, 10,263,441, and 349,607). However, none of these incorporate the power electronics enabling two-way device communication and power negotiation that USB fast-charging standards require. As a result, the maximum power at which they can charge USB devices, including smartphones, is less than 10 watts-less than half the charge rate at which smartphones are able to charge. All of the prior art in question was developed after the introduction of USB fast-charging standards. Higher power of course means faster charging, and in situations to which a hand-cranked USB charger is most applicable, speed is everything. The last thing a person with a dead phone in a power outage or emergency situation is in a position to do is crank for minutes on end to get their phone to power on, then have it die again because they can't deliver enough power to keep it running.
The shortcoming of these hand-cranked USB chargers is not simply a failure to specify the power electronics allowing them to comply with USB fast-charging standards. To illustrate this point, imagine for a moment that we simply incorporated the updated power electronics associated with USB fast-charging to the hand-cranked USB chargers in the prior art. They would still have difficulty generating more than 10 watts because they do not incorporate a means of securing the generator to a solid object during operation so that it keeps still. In my experience, using one hand to crank and the other to hold the generator or hold it still, as the prior art requires, becomes infeasible with the cranking power associated with USB fast-charging. This operational requirement of the prior art also means that users are unable to crank with one hand while using the other for another task such as operating the electronic device being charged. This scenario becomes particularly likely if the device has just been powered back on after having died, is being used, and requires more power to stay on. Smartphones, laptops, and GPS units are among the devices to which this scenario would apply.
I have been obliged to treat the prior art of gravity-powered generators separately from human-powered generators. This is illustrative of another shortcoming of the prior art: a single electricity generator powered by either human muscle energy or gravity, or both at the same time, has not been described in the prior art. Gravity-powered generators tend to use drive mechanisms that convert linear motion to rotary motion that drives the generator, while human-powered generators tend to use rotary input motion directly. Neglecting to accommodate these two types of drive mechanism is among the reasons the prior art has neither diversified its means of harnessing energy from human muscles or gravity, nor been able to combine them.
The present invention is a portable power source capable of charging battery-powered electronic devices in compliance with USB fast-charging standards such as USB Power Delivery and Qualcomm Quickcharge. It does this by converting human muscle energy, gravitational potential energy, or a combination of both to electrical power. Human muscle energy or gravitational energy is delivered by a crank arm or a wheel coupled to a first rotational element.
Both the crank arm and wheel removably attach to the first rotational element via a collar attached to the first rotational element. This allows a user to choose between the crank arm and wheel as the means of operating the portable power source. It also allows the portable power source to be compactly stored and helps prevent damage during transport.
When human muscle energy effects rotation of the crank arm, the first rotational element rotates. When human muscle energy, gravitational energy, or a combination of both effects rotation of the wheel, the first rotational element rotates. Rotation of the crank arm is accomplished by directly rotating the end of the crank arm. Rotation of the wheel is accomplished by pulling a flexible element such as a string wrapped around the periphery of the wheel so that linear motion along the flexible element effects rotary motion of the wheel as the flexible element unwinds from the wheel. The pulling of the flexible element is accomplished by pulling its end in a direction roughly tangential with the wheel, as by the action of walking, biking, or any other means of human transport. The flexible element can be pulled downward by the action of gravity on a weight inside a receptacle connected to the end of the flexible element. Human muscle energy and gravitational energy can effect rotation of the wheel in combination if a person pulls the end of the flexible element while moving downward. This can be done by walking, bicycling, or conducting any other means of human transport down a hill, staircase, or any other physical feature allowing movement that is at least partially downward. One or more humans can also hang with some or all of their weight applied to the end of the flexible element so that the action of gravity on their mass produces the gravitational energy effecting rotation of the wheel.
The rate of rotation of the first rotational element is increased via a gear ratio and delivered to a second rotational element. The second rotational element drives a generator that produces a first electrical output, or a combination of voltage and current. The first electrical output is input to a charge control circuit. The charge control circuit is equipped with the ability to negotiate power levels (voltage and current combinations) with attached electronic devices in accordance with USB fast-charging standards. The voltage and current combination output from the charge control circuit, or the DC electrical output, will depend on the voltage and current combination that the charge control circuit has negotiated with the attached electronic device. The DC electrical output is delivered via a USB interface. This interface can include USB-C, USB-A, a combination of both, or any other USB interface.
A first embodiment illustrated in
A third embodiment illustrated in
A fourth embodiment illustrated in
Additional embodiments result from combining the third and fourth embodiments. Any linear movement tangential to wheel 132 converts linear motion to rotational input energy that the generator system can convert to electrical power for the purpose of fast-charging electronic devices. Flexible member free end 149 (
Additional embodiments result from mass 155 being provided by various objects, such as water, stones, or any other massive objects or combinations of massive objects that can be placed in receptacle 156. Mass 155 could also be part or all of a human's body weight. If the generator system with the wheel system mounted on a horizontal or vertical surface is on an elevated ledge, for example, and a person steps off the ledge and into the receptacle, gravity acting on their mass would become the energy source for producing electrical power that can fast-charge electronic devices. If the ledge is positioned at the top of a staircase, such as the kind found inside a multi-story dwelling, outside an office building, or leading up to a patio, a person could repetitively ascend the steps, step off the ledge into the receptacle to descend in order to provide electrical power to charge their device, re-ascend the steps, rewind flexible element 150 onto wheel 132, step into the receptacle to descend in order to provide electrical power to charge their device, and so on.
Additional embodiments result from varying the mounting angle of the generator system. In addition to horizontal mounting surface 108 oriented at zero degrees with the horizon, and vertical mounting surface 130 oriented at 90 degrees with the horizon, any mounting surface angle between zero and 360 degrees with the horizon (where angles between 180 and 360 degrees would represent orientations with the mounting surface situated above the generator system) is possible, such as a slanted rooftop or ceiling.
Additional embodiments result from means of smoothing capacitance 94 being removed from all embodiments previously described. In its place a buck controller can be used to limit the voltage of the first electrical output to levels appropriate to charge control circuit 78.
Additional embodiments result from charge control circuit 78 being incorporated via means other than charge control PCB 79. PCB 79 could be modified to allow charge control circuit 78 to deliver higher power output and faster charging speeds as allowed by USB fast-charging standards.
Additional embodiments result from varying the operational values of gear ratio 47 and generator 50. For example, it is possible to use a gear ratio greater than or less than 30:1 or a motor with rated power less than or greater than 40 W watts, rated voltage of less or greater than 24V, or operating speed less or more than 1800 RPM.
Additional embodiments result from first rotational element 32 being comprised of something other than shaft 31 and key 34. Examples of rotational elements that fulfill the function of transferring to a generator rotational energy that can fast-charge a device via USB in the same manner as shaft 31 and key 34 include gears, sprockets, splined shafts, splined hollow cylinders, and belt-driven wheels.
Additional embodiments result from gear ratio 47 being provided by a means other than gears, such as differentially sized wheels or sprockets driven by belts or chains.
The portable electricity generator herein described is able to deliver many times more charge power to electronic devices charged via USB than the prior art. It does this by incorporating power electronics allowing it to operate in accordance with USB fast-charging standards. While hand-cranked portable electricity generators described in the prior art require two-handed operation, all embodiments of the portable electricity generator herein described that involve hand cranking allow for one-handed operation. While no portable electricity generators able to charge electronic devices via USB in the prior art are powered by gravitational potential energy, several embodiments of the portable electricity generator herein described are powered by gravitational potential energy. While no electricity generators able to charge electronic devices via USB described in the prior art can combine energy sources, embodiments of the portable electricity generator described herein can operate on a combination of human muscle energy and gravitational potential energy.
This application claims the benefit of provisional patent application Ser. No. 62/965,811, filed Jan. 25, 2020 by the present inventor, which is incorporated by reference in its entirety.