WO2020122873A1

WO2020122873A1 - Air pressure driven dc voltage power supply

Info

Publication number: WO2020122873A1
Application number: PCT/US2018/064871
Authority: WO
Inventors: Michael J. Holihan; David R. Sar; David D. Crouch; Kenneth E. Prager
Original assignee: Raytheon Company
Priority date: 2018-12-11
Filing date: 2018-12-11
Publication date: 2020-06-18

Abstract

An air pressure driven DC voltage power supply includes both a pneumatic and a DC motor which are configured to convert the pneumatic energy in the tires of a vehicle to a DC voltage to provide power to a device.

Description

AIR PRESSURE DRIVEN DC VOLTAGE POWER SUPPLY

FIELD

This disclosure relates generally to an air pressure driven power supply for providing power to a device, for example, jump starting a battery of an internal combustion engine.

BACKGROUND

During normal operation, a vehicle can become disabled on a roadside or other area because of a dead battery, potentially leading to harm if the vehicle’s occupants cannot safely leave the vehicle. In such cases, a donor vehicle for jump starting the battery of the inoperative vehicle may not be readily available. While specialized carry-on batteries (typically including a compact lithium battery with attached jumper cables) are sometimes available, these devices may also become low or depleted of voltage. In addition, certain types of vehicles typically need to turn on their vehicles every few hours to keep

communication systems (e.g., radios and other electronic equipment) from draining their own batteries, thus requiring a continuously-reliable source of power. Accordingly, what is needed is a system for providing voltage to a depleted battery of a vehicle or other electronic equipment.

BRIEF SUMMARY

Described herein is an air pressure driven DC voltage power supply for use with a vehicle which provides an alternative to conventional jump starting methods. The power supply of this disclosure includes both a pneumatic and a DC motor which are configured to use the high pressure compressed air available in the tires of the vehicle to convert the pneumatic energy to DC voltage to either start the vehicle or to temporarily power-up electronic equipment. The power supply of this disclosure may also be used to energize or power stand-alone equipment (such as communications equipment) not otherwise attached to the vehicle.

Further examples of the air pressure driven DC voltage power supply of this disclosure may include one or more of the following, in any suitable combination. In examples, an air pressure driven DC voltage power supply of this disclosure includes a pneumatic motor configured to be fluidly attached to a pressurized air source. The pneumatic motor includes a rotary shaft configured to rotate in response to pressurized air.

The power supply also has a DC motor including a rotatable armature for generating a DC current at an output. The armature is coupled to the rotary shaft of the pneumatic motor. The generated DC current is provided to a device. In examples, the pressurized air source is a pneumatic tire of a vehicle or an air pump. In examples, the pneumatic motor is a rotary air vane motor. In examples, the DC motor is a permanent magnet DC motor. In examples, the device is a rechargeable battery of an internal combustion engine. In examples, the power supply further includes a voltage regulator coupled to the output of the DC motor. In examples, the power supply is at least partially contained within a housing. In further examples, the housing is configured to be carried.

In other examples, a method of converting air pressure to DC voltage of this disclosure includes attaching an air pressure driven DC voltage power supply to a pressurized air source. The power supply has a pneumatic motor including a rotary shaft configured to rotate in response to pressurized air and a DC motor including a rotatable armature for generating a DC current at an output. The armature is coupled to the rotary shaft of the pneumatic motor. The pressurized air is enabled to flow into the pneumatic motor such that the rotary shaft of the pneumatic motor is rotated, thus rotating the armature of the DC motor to generate the DC current. In examples, the pressurized air source is a pneumatic tire of a vehicle or an air pump.

In further examples, a method of jump starting a battery of a vehicle of this disclosure includes attaching flexible tubing of an air pressure driven DC voltage power supply to a pressurized air source. The power supply further has a pneumatic motor configured to be fluidly attached to a pressurized air source. The pneumatic motor includes a rotary shaft configured to rotate in response to pressurized air. The power supply also has a DC motor including a rotatable armature for generating a DC current at an output. The armature is coupled to the rotary shaft of the pneumatic motor. A valve fluidly coupled between the air source and the pneumatic motor is opened to allow the pressurized air to flow into the pneumatic motor such that the rotary shaft of the pneumatic motor is rotated, thus rotating the armature of the DC motor to generate the DC current. The plurality of wires of the DC motor are attached to the battery of the vehicle to jump start the battery. In examples, the pressurized air source is a pneumatic tire of a vehicle or an air pump.

In yet further examples, an air pressure driven DC voltage power supply of this disclosure includes a pneumatic motor configured to be fluidly attached to a reservoir. The power supply also includes a DC motor for generating a DC current at an output for application to a battery and an air pump coupled to the DC motor configured to be fluidly attached to the reservoir. A switch is located between the battery and the DC motor. The switch is configured to switch the power supply between a first configuration, wherein the DC motor provides the DC current to the battery, and a second configuration, wherein the air pump provides air to the reservoir. In examples, the power supply further includes a fluid valve between the reservoir and the pneumatic motor. The fluid valve is configured to selectively allow the air to flow between the reservoir and the pneumatic motor, or between the air pump and the reservoir. In examples, the power supply further includes a plurality of drive gears between the DC motor and the pneumatic motor. In examples, the plurality of drive gears includes a first drive gear coupled to the air pump, a second drive gear coupled to the pneumatic motor, and a third drive gear coupled to the DC motor. In examples, when the power supply is in the first configuration, the second drive gear couples to the third drive gear and is decoupled from the first drive gear and, when the power supply is in the second configuration, the third drive gear couples to the first drive gear and is decoupled from the second drive gear.

These and other features and advantages will be apparent from a reading of the following detailed description and a review of the associated drawings. It is to be understood that both the foregoing general description and the following detailed description are explanatory only and are not restrictive of aspects as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will be more fully understood by reference to the detailed description, in conjunction with the following figures, wherein:

FIG. 1 illustrates an exemplary housing of the air pressure driven DC voltage power supply of this disclosure;

FIG. 2 illustrates an example of a pneumatic motor for use in the power supply; FIG. 3 illustrates an example of a DC motor for use in the power supply; and

FIG. 4 is a block diagram of a power supply in accordance with one aspect of the present disclosure;

FIG. 5 is a block diagram of a power supply in accordance with another aspect of the present disclosure; and

FIG. 6 is a schematic diagram of a gearing system in the power supply of FIG. 5.

DETAILED DESCRIPTION

In the description that follows, like components have been given the same reference numerals, regardless of whether they are shown in different examples. To illustrate example(s) in a clear and concise manner, the drawings may not necessarily be to scale and certain features may be shown in somewhat schematic form. Features that are described and/or illustrated with respect to one example may be used in the same way or in a similar way in one or more other examples and/or in combination with or instead of the features of the other examples.

As used in the specification and claims, for the purposes of describing and defining the disclosure, the terms“about” and“substantially” are used to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. The terms“about” and“substantially” are also used herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue. “Comprise,” “include,” and/or plural forms of each are open ended and include the listed parts and can include additional parts that are not listed.“And/or” is open-ended and includes one or more of the listed parts and combinations of the listed parts.

One readily-available power source that is often overlooked is pneumatic energy, i.e., pressurized air as found in, for example, a tire. In particular, the tires of heavy duty vehicles (such as military or emergency vehicles) typically have air pressure that well exceeds that of commercial vehicles (i.e., 72 psi or higher) in a minimum of four tires. In one example, the potential available energy in a quantity of compressed air in the tires of heavy-duty vehicles can be calculated as follows: RT[(Po/Pl)-l+ln(Pl/Po)] (Equation 1) where:

R=0.287 for air

T= °K (assume 273, or 32 °F)

Po=l atm

Pl=5 atm (75 PSI)

This calculates to > 63.42 KJ/Kg of air at 75 PSI.

Even when other factors are taken into account, such as the constancy of the air pressure and isothermal efficiency, the potential available energy may be estimated to be about 40 KJ/Kg. Thus, it is clear that tire pressure in a heavy-duty vehicle can potentially provide a large, untapped reservoir of energy which may be converted for use in a DC battery during an emergency situation.

Turning now to FIG. 1, an example of a housing 102 for the air pressure driven DC voltage power supply of this disclosure is illustrated. The housing 102 is generally configured for holding the various components (described below) of the power supply 100. In non limiting examples, the housing 102 may be made of a lightweight, rigid material, such as plastic, and appropriately sealed to be watertight. The housing 102 may also be sized and shaped to be mounted to a surface of a vehicle. Alternatively, the housing 102 may comprise a handle 101 to allow the housing 102 to be carried. A surface of the housing 102 may include projections 104a for storing and protecting a length of flexible tube 106 (such as rubber hosing) extending from the interior of the housing 102. A free end of the flexible tube 106 may include a tire air fitting (not shown) for attaching to the valve stem of a pneumatic tire. The surface of the housing 102 may also include projections 104b for storing and protecting one or more jumper cables 108 extending from the interior of the housing 102. The jumper cables 108 may be configured for attachment to a device in need of a charge, such as a battery of the vehicle. The housing 102 may also include a control panel 110 for controlling the various electronic components of the power supply 100. Such components may include an LED display 112 for displaying a bar graph meter, a valve 148 attached to a source of pressurized air within the housing 102, and a voltage range selector 116 for selecting an output voltage, among other components. The air pressure driven DC voltage power supply 100 of this disclosure will now be described with regard to FIGS. 2-4. The primary components of the power supply 100 stored within the housing 102 consist of a pneumatic motor 120, such as a rotary air vane motor (FIG. 2) and a DC motor 140, such as a 12V or 24V permanent magnet DC motor (FIG. 3). However, it is contemplated that other sources of compressed air, such as air pumps, and other types of DC receivers/motors/voltage generators could be used.

Turning now to FIG. 2, an example of a pneumatic motor 120 for use in the power supply 100 of this disclosure is shown. As shown in FIG. 2, the pneumatic motor 120 is generally configured to receive air flow and convert it to torque and rotational motion. As such, the pneumatic motor 120 may comprise a cylindrical stator or body 122 containing a rotary shaft 124. Attached to the rotary shaft 124 are a plurality of blades or vanes 126 which are configured to rotate freely within the body 122. As the rotary shaft 124 rotates, a centrifugal force creates pressure chambers 128 between the vanes 126. The pneumatic motor 120 is fluidly attached to a pressurized air source and, as pressurized air from the pressure source enters through an inlet port 130, the volume of the first compression chamber 128 increases as the air within the chamber 128 expands. The next compression chamber 128 is in turn submitted to the pressurized air and the same phenomenon occurs, allowing for constant rotation of the rotary shaft 124. The pressurized air may then be released through an exhaust port 132. The rotation of the rotary shaft 124 can thus be used to supply torque and rotation to a rotor or rotatable armature 144 of the DC motor 140, shown in FIG. 3. In FIG. 3, an example of the DC motor 140 comprises two magnets (not shown) which are mounted on the inner periphery of a cylindrical metal body 142, creating a magnetic field. The armature 144 is configured to rotate within the magnetic field for producing DC power which is conducted from the DC motor 140 via a plurality of wires 141 attached to the DC motor 140.

Turning now to FIG. 4, an example arrangement of the components of the power supply 100 of this disclosure are illustrated in a schematic form. As shown in FIG. 4, the power supply 100 includes the pneumatic motor 120 coupled in-line to the armature 144 of the DC motor 140. In one aspect, the plurality of jumper cables 108 are attached to the DC motor 140. A voltage regulator circuit 134 may be provided between the output of the DC motor 140 and a device 136 in need of a charge (such as a rechargeable battery) to taper the outgoing voltage produced by the DC motor 140 to accommodate the device 136. Notably, while one aspect of the present disclosure is directed to a rechargeable battery, the power supply 100 could also be packaged in a housing that is small enough and light enough for a person to carry over long distances, and which could be attached to a tire to provide an output voltage to emergency power other devices 136, for example, a CB radio, a mobile phone and/or other communication device.

In use, to provide voltage to the device 136, the flexible tube 106 is attached to a pressurized air source 138. For example, the flexible tube 106 is attached to a tire via a tire air fitting on the flexible tube 106 to the valve stem of the tire. A valve 148, such as a ball valve, is coupled to the flexible tube 106 between the output of the air source 138 and prior to the pneumatic motor 120. Rotating the valve 148 allows compressed air from the air source 138 to flow rapidly through the pneumatic motor 120 of the power supply 100, eventually rotating the armature 144 of the DC motor 140 and applying the resulting DC voltage to the device 136. The faster the armature rotates 144, the higher the output voltage. If the device 136 is a depleted battery of a vehicle, once the voltage is applied to the device 136, the user will be able to start the vehicle. A voltage converter 150, such as a DC-to-AC converter or a DC-to-DC converter, could also be added to the output of the DC motor 140. This would provide, for example, 110V AC or a stable DC output for use in powering communication equipment, such as a cell phone, CB unit, and the like. In further examples, not shown, the power supply 100 may also include other components, such as safety fusing, and/or an air limiting device to prevent the air source 138 from becoming completely depleted.

Turning now to FIG. 5, in another aspect of the present disclosure, of the power supply 500 could be configured to operate“in reverse.” That is, once the vehicle is started and running, the power supply 500 could also be used to re-fill the depleted air source, which now functions as a reservoir 538. In this aspect, the power supply 500 may be provided with an air pump 560 (for example, a 12V or 24V air compressor pump) directly geared to the DC motor 540. The air pump 560 is fluidly connected to a three-way fluid valve 505 provided between the reservoir 538 and the pneumatic motor 520. The fluid valve 505 is configured to selectively allow air to flow between the reservoir 538 and the pneumatic motor 520, or from the air pump 560 back to the reservoir 538 (for example, by closing off one of the three outputs). A switch 564, controllable at control 530, is provided between the battery 525 or other devices 520 and the DC motor 540. The switch 564 is configured to switch the power supply 500 between a first configuration (i.e., wherein the DC motor 540 is being driven by the pneumatic motor 520 and producing an output voltage to power the battery 525 or other devices 520) and a second configuration (i.e., wherein the battery 525 is driving the DC motor 540 directly geared to the air pump 560 to refill the reservoir 538).

Still referring to FIG. 5, a selectable coupler 510, also controlled at control 530, is provided between the DC motor 520 and the pneumatic motor 540. As shown in FIG. 6, in an example, the selectable coupler 510 may comprise a plurality of drive gears 552a, b,c. Drive gear 552a is coupled to the air pump 560, drive gear 552b is coupled to the pneumatic motor 520, and drive gear 552c is coupled to the DC motor 540. When the power supply 500 is in the first configuration, drive gear 552b couples to drive gear 552c and is decoupled from drive gear 552a. When the power supply 500 is in the second configuration, drive gear 552c couples to drive gear 552a and is decoupled from drive gear 552b.

While this disclosure has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present application as defined by the appended claims. Such variations are intended to be covered by the scope of this present application. As such, the foregoing description of embodiments of the present application is not intended to be limiting, the full scope rather being conveyed by the appended claims.

Claims

CLAIMS What is claimed is:

1. An air pressure driven DC voltage power supply comprising:

a pneumatic motor configured to be fluidly attached to a pressurized air source, the pneumatic motor including a rotary shaft configured to rotate in response to pressurized air; and

a DC motor including a rotatable armature for generating a DC current at an output, the armature coupled to the rotary shaft of the pneumatic motor;

wherein the generated DC current is provided to a device.

2. The power supply of claim 1, wherein the pressurized air source is a pneumatic tire of a vehicle.

3. The power supply of claim 1, wherein the pressurized air source is an air pump.

4. The power supply of any of claims 1-3, wherein the pneumatic motor is a rotary air vane motor.

5. The power supply of any of claims 1-4, wherein the DC motor is a permanent magnet DC motor.

6. The power supply of any of claims 1-5, wherein the device is a rechargeable battery of an internal combustion engine.

7. The power supply of any of claims 1-6, further comprising a voltage regulator coupled to the output of the DC motor.

8. The power supply of any of claims 1-7, wherein the power supply is at least partially contained within a housing.

9. The power supply of claim 8, wherein the housing is configured to be carried.

10. A method of converting air pressure to DC voltage, comprising:

attaching an air pressure driven DC voltage power supply to a pressurized air source, the power supply comprising:

a pneumatic motor including a rotary shaft configured to rotate in response to pressurized air; and

a DC motor including a rotatable armature for generating a DC current at an output, the armature coupled to the rotary shaft of the pneumatic motor; and enabling the pressurized air to flow into the pneumatic motor such that the rotary shaft of the pneumatic motor is rotated, thus rotating the armature of the DC motor to generate the DC current.

11. The method of claim 10, wherein the pressurized air source is a pneumatic tire of a vehicle.

12. The method of claim 10 or 11, wherein the pressurized air source is an air pump.

13. A method of jump starting a battery of a vehicle, comprising:

attaching flexible tubing of an air pressure driven DC voltage power supply to a pressurized air source, the power supply further comprising:

a pneumatic motor configured to be fluidly attached to a pressurized air source, the pneumatic motor including a rotary' shaft configured to rotate in response to pressurized air; and

opening a valve fluidly coupled between the air source and the pneumatic motor to allow the pressurized air to flow into the pneumatic motor such that the rotary shaft of the pneumatic motor is rotated, thus rotating the armature of the DC motor to generate the DC current; and attaching the plurality of wires of the DC motor to the battery of the vehicle to jump start the battery.

14. The method of claim 13, wherein the pressurized air source is a pneumatic tire of a vehicle.

15. The method of claim 13 or 14, wherein the pressurized air source is an air pump.

16. An air pressure driven DC voltage power supply comprising:

pneumatic motor configured to be fluidly attached to a reservoir;

a DC motor for generating a DC current at an output for application to a battery'; an air pump coupled to the DC motor configured to be fluidly attached to the reservoir; and

a switch located between the battery and the DC motor;

wherein the switch is configured to switch the power supply between a first configuration, wherein the DC motor provides the DC current to the battery, and a second configuration, wherein the air pump provides air to the reservoir.

17. The power supply of claim 16, further comprising a fluid valve between the reservoir and the pneumatic motor, the fluid valve configured to selectively allow the air to flow between the reservoir and the pneumatic motor, or between the air pump and the reservoir.

18. The power supply of claims 16 or 17, further comprising a plurality of drive gears between the DC motor and the pneumatic motor.

19. The power supply of claim 18, wherein the plurality of drive gears comprises a first drive gear coupled to the air pump, a second drive gear coupled to the pneumatic motor, and a third drive gear coupled to the DC motor.

20. The power supply of claim 19, wherein, when the power supply is in the first configuration, the second drive gear couples to the third drive gear and is decoupled from the first drive gear and, when the power supply is in the second configuration, the third drive gear couples to the first drive gear and is decoupled from the second drive gear.