Abstract:
A vehicle suspension kinetic energy recovery system generates useful energy from the up-and-down motion of a vehicle suspension caused by roadway irregularities as the vehicle travels down the roadway. In one embodiment, a piston-type pump mounted between the frame and the suspension charges a high-pressure accumulator for driving hydraulic motors, e.g., power windows, power seats, alternator, etc. In another embodiment, electricity is generated directly by a conductor moving with respect to magnetic field as a result of the up-and-down motion of the vehicle suspension. In yet another embodiment, an air compressor mounted between the frame and suspension compresses air for storage in a pressure tank and, thereafter, to power pneumatic devices.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    This invention relates to a vehicle suspension kinetic energy recovery system and, more particularly, but not by way of limitation, to a method and apparatus for converting the kinetic energy of vehicle suspension movement to useful energy. 
         [0003]    2. Discussion 
         [0004]    World-wide demand for oil increasingly strains the available supply. The need for more oil means higher prices and more pollution. 
         [0005]    With gas prices on the rise, people and businesses are looking for environmentally sound solutions. New technologies have emerged to combat rising gas prices and decrease pollution. Fuel cell vehicles run on hydrogen and emit only water vapor. Biofuel vehicles run on fuel made from plants. Electric vehicles can run on rechargeable batteries, and hybrid vehicles use a combination of a gasoline engine and another type of power plant. 
         [0006]    A hybrid pairing a gasoline engine with an electric motor powered by lithium ion batteries results in increased fuel economy and reduced pollution. A process called regenerative braking charges the batteries when the car brakes, thereby converting friction energy, which is normally lost in conventional vehicles, to electrical energy stored within the lithium ion batteries. The lithium ion batteries then power the electric motor. The electric motor in most cars generally is sufficiently powerful only to move the car at slow speeds. In most gas/electric hybrids, the gas engine takes over once the car reaches a speed of 20-30 miles per hour. Thereafter, the car operates like a conventional gasoline powered vehicle. Still, use of gas/electric hybrids cuts down on fuel consumption and emissions. 
         [0007]    Although gas/electric hybrids use less fuel and generate less pollution than conventional cars, they have limitations. Extra batteries and the electric motor add substantial weight to the car, thereby decreasing efficiency. The batteries contain toxic materials which present disposal problems. As stated earlier, once a gas/electric hybrid reaches a speed of 20-30 miles per hour, it operates as a conventional gasoline-powered vehicle (but with extra weight due to the batteries and the electric motor). 
         [0008]    Hydraulic hybrids pair a gasoline engine with a hydraulic power plant. A pump moves hydraulic fluid from a low-pressure reservoir to a high-pressure accumulator. The accumulator contains not only the fluid supplied by the pump but also pressurized nitrogen gas. As with gas/electric hybrids, regenerative braking gathers the energy which is stored in the high-pressure accumulator. Kinetic energy from the brakes powers the pump. As the vehicle slows, the pump starts up and moves fluid from the reservoir to the accumulator. The increased pressure in the accumulator acts like a fully charged battery in a gas/electric hybrid. Hydraulic hybrids offer an advantage over gas/electric hybrids, however, in that the accumulator sends its energy (in the form of nitrogen gas) directly to the vehicle&#39;s drive shaft. The vehicle accelerates and the pump moves the fluid back to the reservoir, ready to charge the accumulator again on the next application of the vehicle brakes. 
         [0009]    All hydraulic hybrids use reservoirs, accumulators, and pumps, but those components can be coupled with a vehicle in two ways. A parallel hydraulic hybrid simply connects the hybrid components to a conventional transmission and drive shaft. This approach allows the hydraulic system to assist the gasoline engine in acceleration—when the gasoline engine works its hardest—but it does not allow the gasoline engine to shut off when the vehicle isn&#39;t in motion. Thus the vehicle is always burning gasoline, unlike gas/electric hybrids, whose engines shut off at slow speeds or when the vehicle is stopped. Still, the parallel hydraulic system provides significant benefits, including a 40 percent increase in fuel economy, according to the United States Environmental Protection Agency (EPA). Parallel hybrid systems are also adaptable for addition to conventional gasoline-powered vehicles. Currently, however, parallel hydraulic vehicles are built with the system in place and are used primarily in heavy-duty delivery vehicles. 
         [0010]    Series hydraulic systems, while using the same regenerative braking process as parallel hydraulic systems, do not use a conventional transmission or drive shaft and transmit power almost directly to the wheels. Fewer components makes series hydraulic systems more efficient. Since the hydraulic system itself is turning the wheels, the vehicle&#39;s gasoline engine can be shut off, resulting in even more fuel savings. According to NextEnergy, a Michigan nonprofit organization founded in 2002 to accelerate research, development and manufacturing of alternative energy techniques, series hydraulic hybrids are estimated to improve fuel economy by 60 to 70 percent with a comparable reduction in emissions. In 2005, the EPA announced that it had partnered with UPS and Eaton Corporation-Fluid Power to create a number of series hydraulic-powered trucks for UPS. The truck looks like a regular UPS delivery van, but it has a series hydraulic hybrid propulsion system. 
         [0011]    The EPA chose to put its efforts into a delivery van, rather than a passenger car, because of the source of the power. The hydraulic hybrid system (whether parallel or series) gets its power through regenerative braking. At highway speeds, a hydraulic hybrid isn&#39;t much different from a regular car. In traffic, however (especially in stop-and-go traffic), a series hydraulic hybrid can shut its engine off and use hydraulic power alone. Stopping and starting is the key to saving fuel with a hydraulic hybrid. Because UPS trucks encounter a lot of stop-and-go traffic, they are the perfect vehicle for hydraulic hybrid systems. UPS trucks go from one stop to the next, often in urban traffic, and seldom travel on the highway. They are also often left on as drivers make pickups and deliveries. In conventional UPS trucks, the idling vehicle creates pollution and adds to the company&#39;s fuel costs. The series hydraulic hybrid truck permits the gasoline engine to be shut off while the truck is on. Moreover, by cutting the fuel used and pollutants emitted by one large truck, there is a bigger impact overall than cutting the fuel and pollution of a smaller vehicle. 
         [0012]    The increases in fuel economy associated with a series hydraulic hybrid generate huge savings, both financially and environmentally. Because the energy in a hydraulic hybrid doesn&#39;t pass through an electric motor, it recovers more energy normally lost during braking. According to NextEnergy, a gas/electric hybrid recovers 30 percent of braking energy, while a hydraulic hybrid can recover 70 percent. The EPA estimates that carbon dioxide emissions from hydraulic hybrid UPS trucks are 40 percent lower than conventional UPS trucks. The EPA also estimates that with less maintenance than a gas/electric hybrid and less fuel than a conventional truck, UPS could save up to $50,000 over the life span of each hydraulic hybrid truck. Another payoff lies in the efficiency of the hydraulic components themselves. Because the hydraulic components are lightweight and use simple mechanics, they are easy to build, maintain, and repair. In contrast, gas/electric hybrids use heavy batteries that may become obsolete and generate hazardous disposal challenges. 
         [0013]    Yet current hydraulic hybrid vehicles have limitations. Their energy is derived solely from regenerative braking. At highway speeds, the absence of braking means no power can be produced by the hydraulic system. Even at low speeds, most modern cars have a number of electrical systems to power such things as radios, air conditioner fans, electrically-operated windows, electrically-adjusted seats, seat heaters, etc. Those systems are powered by a conventional car&#39;s battery, which is charged by the car&#39;s gasoline engine. If the engine shuts off and the electronics stay on, the battery is drained. In gas/electric hybrids, the extra batteries can keep the electrical components running while the engine is shut off during a stop. Hydraulic hybrids, however, lack the extra batteries needed to power electrical systems when the engine turns off. While the lack of extra batteries not a big deal for parallel hydraulic hybrids, whose engines do not shut off during vehicle stops, it is a major problem for series hydraulic hybrids. Series hydraulic hybrids offer the best fuel efficiency, but series hydraulic hybrids can&#39;t power a radio or air conditioner when the vehicle stops, making series hydraulic hybrids generally unsuitable for most American consumers. 
         [0014]    The job of a car suspension is to maximize the friction between the tires and the road surface, to provide steering stability with good handling, and to ensure the comfort of the passengers. If a road were perfectly flat, with no irregularities, suspensions wouldn&#39;t be necessary. But roads are far from flat. Even freshly paved highways have subtle imperfections that can interact with the wheels of a car. These imperfections apply forces to the wheels. According to Newton&#39;s laws of motion, all forces have both magnitude and direction. A bump in the road causes the wheel to move up and down perpendicular to the road surface. The magnitude, of course, depends on whether the wheel is striking a giant bump or a tiny speck. Either way, the car wheel experiences a vertical acceleration as it passes over any roadway imperfection (sometimes also referred to herein as roadway irregularity). 
         [0015]    Without an intervening structure, all of wheel&#39;s vertical energy is transferred to the frame, which moves in the same direction. In such a situation, the wheels can lose contact with the road completely. Then, under the downward force of gravity, the wheels can slam back into the road surface. The study of the forces at work on a moving car is called vehicle dynamics, and most automobile engineers consider the dynamics of a moving car from two perspectives—Ride and Handling. Ride is a car&#39;s ability to smooth out a bumpy road. Handling is a car&#39;s ability to safely accelerate, brake and corner. These two characteristics can be further described in three important principles—road isolation, road holding, and cornering. 
         [0016]    Road isolation refers to the vehicle&#39;s ability to absorb or isolate road shock from the passenger compartment, thereby allowing the vehicle body to ride undisturbed while traveling over rough roads. The suspension absorbs energy from road bumps and dissipates the energy without causing undue oscillation in the vehicle. 
         [0017]    Road holding refers to the degree to which a car maintains contact with the road surface in various types of directional changes and in a straight line. For example, the weight of a car will shift from the rear tires to the front tires during braking. Because the nose of the car dips toward the road, this type of motion is known as “dive.” The opposite effect—“squat”—occurs during acceleration, which shifts the weight of the car from the front tires to the back. The suspension keeps the tires in contact with the ground, because it is the friction between the tires and the road that affects a vehicle&#39;s ability to steer, brake and accelerate. The suspension also minimizes the transfer of vehicle weight from side to side and front to back, as this transfer of weight reduces the tire&#39;s grip on the road. 
         [0018]    Cornering refers to the ability of a vehicle to travel a curved path. The suspension minimizes body roll, which occurs as centrifugal force pushes outward on a car&#39;s center of gravity while cornering, raising one side of the vehicle and lowering the opposite side. The suspension also transfers the weight of the car during cornering from the high side of the vehicle to the low side. Road isolation, road holding, and cornering involve almost constant vertical movement of the suspension with respect to the frame. 
         [0019]    The suspension of a car is actually part of the chassis, which includes all of the important systems located beneath the car&#39;s body. These systems include the frame, the suspension system, the steering system, and the tires and wheels. The frame supports the car&#39;s engine and body, which are, in turn, supported by the suspension. The suspension supports weight, absorbs and dampens shock, and helps maintain tire contact with the roadway. The steering system enables the driver to guide and direct the vehicle. The tires and wheels make vehicle motion possible by way of or friction with the road. 
         [0020]    The three fundamental components of any suspension are springs, dampers and anti-sway bars. Today&#39;s springing systems are based on one of four basic designs. Suspension coil springs are, essentially, a heavy-duty torsion bar coiled around an axis. Suspension coil springs compress and expand to absorb the motion of the wheels. Leaf springs consist of several layers of metal (called “leaves”) bound together to act as a single unit. Leaf springs were first used on horse-drawn carriages and were found on most American automobiles until 1985. They are still used today on most trucks and heavy-duty vehicles. Torsion bars use the twisting properties of a steel bar to provide coil-spring-like performance. One end of a bar is anchored to the vehicle frame. The other end is attached to a wishbone, which acts like a lever that moves perpendicular to the torsion bar. When the wheel hits a bump, vertical motion is transferred to the wishbone and then, through the levering action, to the torsion bar. The torsion bar then twists along its axis to provide the spring force. European car makers used this system extensively, as did Packard and Chrysler in the United States, through the 1950s and 1960s. Air springs, which consist of a cylindrical chamber of air positioned between the wheel and the car&#39;s body, use the compressive qualities of air to absorb wheel vibrations. The concept is actually more than a century old and could be found on horse-drawn buggies. Air springs from this era were made from air-filled, leather diaphragms, much like a bellows; they were replaced with molded-rubber air springs in the 1930s. 
         [0021]    Based on where springs are located on a car—i.e., between the wheels and the frame—engineers often find it convenient to talk about the sprung mass and the unsprung mass. The sprung mass is the mass of the vehicle supported on the springs, while the unsprung mass is loosely defined as the mass between the road and the suspension springs. The stiffness of the springs affects how the sprung mass responds while the car is being driven. Loosely sprung cars, such as luxury cars, can swallow bumps and provide a super-smooth ride, but loosely sprung cars are prone to dive and squat during braking and acceleration and tends to experience body sway or roll during cornering. Tightly sprung cars, such as sports cars, are less forgiving on bumpy roads, but they minimize body motion well. Tightly sprung cars can be driven aggressively, even around corners. Whether loosely sprung or tightly sprung, the suspension of any vehicle is constantly moving relative to the frame. 
         [0022]    While springs by themselves seem like simple devices, designing and implementing them on a car to balance passenger comfort with handling is a complex task. To make matters more complex, springs alone can&#39;t provide a perfectly smooth ride. Springs are great at absorbing energy, but not so good at dissipating it. Other structures, known as dampers, are required to do this. 
         [0023]    Unless a dampening structure is present, a car spring will extend and release the energy it absorbs from a bump at an uncontrolled rate. The spring will continue to bounce at its natural frequency until all of the energy originally put into it is used up. A suspension built on springs alone would make for an extremely bouncy ride and, depending on the terrain, an uncontrollable car. The shock absorber, or snubber, controls unwanted spring motion through a process known as dampening. Shock absorbers slow down and reduce the magnitude of vibratory motions by turning the kinetic energy of suspension movement into heat energy that can be dissipated through hydraulic fluid. 
         [0024]    A shock absorber is basically an oil pump placed between the frame of the car and the wheels. The upper mount of the shock connects to the frame (i.e., the sprung weight), while the lower mount connects to the axle, near the wheel (i.e., the unsprung weight). In a twin-tube design, one of the most common types of shock absorbers, the upper mount is connected to a piston rod, which in turn is connected to a piston, which in turn sits in a tube filled with hydraulic fluid. The inner tube is known as the pressure tube, and the outer tube is known as the reserve tube. The reserve tube stores excess hydraulic fluid. When the car wheel encounters a bump in the road and causes the spring to coil and uncoil, the energy of the spring is transferred to the shock absorber through the upper mount, down through the piston rod and into the piston. Orifices perforate the piston and allow fluid to leak through as the piston moves up and down in the pressure tube. Because the orifices are relatively tiny, only a small amount of fluid, under great pressure, passes through. This slows down the piston, which in turn slows down the spring. 
         [0025]    Shock absorbers work in two cycles—the compression cycle and the extension cycle. The compression cycle occurs as the piston moves downward, compressing the hydraulic fluid in the chamber below the piston. The extension cycle occurs as the piston moves toward the top of the pressure tube, compressing the fluid in the chamber above the piston. A typical car or light truck will have more resistance during its extension cycle than its compression cycle. With that in mind, the compression cycle controls the motion of the vehicle&#39;s unsprung weight, while extension controls the heavier, sprung weight. All modern shock absorbers are velocity-sensitive—the faster the suspension moves, the more resistance the shock absorber provides. This enables shocks to adjust to road conditions and to control all of the unwanted motions that can occur in a moving vehicle, including bounce, sway, brake dive and acceleration squat. 
         [0026]    Another common dampening structure is the strut—basically a shock absorber mounted inside a coil spring. Struts provide a dampening function like shock absorbers, and they also provide structural support for the vehicle suspension. That means struts deliver a bit more than shock absorbers, which don&#39;t support vehicle weight—they only control the speed at which weight is transferred in a car, not the weight itself. Because shocks and struts have so much to do with the handling of a car, they can be considered critical safety features. Worn shocks and struts can allow excessive vehicle-weight transfer from side to side and front to back. This reduces the tire&#39;s ability to grip the road, as well as handling and braking performance. 
         [0027]    Anti-sway bars (also known as anti-roll bars) are used along with shock absorbers or struts to give a moving automobile additional stability. An anti-sway bar is a metal rod that spans the entire axle and effectively joins each side of the suspension together. When the suspension at one wheel moves up and down, the anti-sway bar transfers movement to the other wheel. This creates a more level ride and reduces vehicle sway. In particular, it combats the roll of a car on its suspension as it corners. Almost all cars today are fitted with anti-sway bars as standard equipment. 
         [0028]    The stopping and starting requirement for regenerative braking on which current electric hybrids and hydraulic hybrids are based is unavailable at highway speeds. What is needed is a device which will capture the kinetic energy of suspension movement and generate power at highway speeds when regenerative braking is not available. 
       SUMMARY OF THE INVENTION 
       [0029]    A vehicle suspension kinetic energy recovery system generates useful energy from the up-and-down motion of a vehicle suspension caused by roadway irregularities as the vehicle travels down the roadway. In one embodiment, a piston-type pump is mounted between the frame and the suspension. When the vehicle frame moves toward the vehicle suspension in response to roadway irregularities, the piston pumps fluid from a low-pressure reservoir to a high-pressure accumulator. The energy stored in the high-pressure accumulator is available to power the vehicle. The energy thus made available can also be used to drive hydraulic motors, e.g., power windows, power seats, etc. In addition, the high pressure fluid can power an alternator which produces electricity for storage in a conventional automobile battery. In another embodiment, electricity is generated directly by a conductor moving with respect to magnetic field as a result of the up-and-down motion of the vehicle suspension. In yet another embodiment, an air compressor mounted between the frame and suspension compresses air for storage in a pressure tank and, thereafter, to power pneumatic devices. 
         [0030]    An object of the present invention is to provide a method and system of recovering the kinetic energy associated with the movement of a vehicle frame relative to the vehicle suspension to power vehicle systems. 
         [0031]    Yet another object of the present invention is to provide a vehicle suspension kinetic energy recovery system which absorbs a portion of the kinetic energy associated with the movement of a vehicle frame relative to the vehicle suspension and recover a portion of the kinetic energy associated with the movement of a vehicle frame relative to the vehicle suspension to power vehicle systems. 
         [0032]    Other objects, features, and advantages of the present invention will become clear from the following description of the preferred embodiment when read in conjunction with the accompanying drawings and appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0033]      FIG. 1  is a block diagram of the functions of the applicant&#39;s vehicle suspension kinetic energy recovery system invention. 
           [0034]      FIG. 2  shows a vehicle suspension kinetic energy recovery system according to applicant&#39;s vehicle suspension kinetic energy recovery system invention. 
           [0035]      FIGS. 3-5  show the operation of applicant&#39;s vehicle suspension kinetic energy recovery system invention when the frame of a vehicle is compressed toward the vehicle suspension. 
           [0036]      FIGS. 6-8  illustrate the operation of applicant&#39;s invention when the frame of a vehicle is extended away from the vehicle suspension. 
           [0037]      FIG. 9  shows another vehicle suspension kinetic energy recovery system according to applicant&#39;s invention. 
           [0038]      FIG. 10  shows another vehicle suspension kinetic energy recovery system according to applicant&#39;s invention. 
           [0039]      FIG. 11  shows another vehicle suspension kinetic energy recovery system according to applicant&#39;s invention. 
           [0040]      FIG. 12  shows another vehicle suspension kinetic energy recovery system according to applicant&#39;s invention. 
           [0041]      FIG. 13  shows another vehicle suspension kinetic energy recovery system according to applicant&#39;s invention. 
           [0042]      FIG. 14  shows another vehicle suspension kinetic energy recovery system according to applicant&#39;s invention. 
           [0043]      FIG. 15  shows another vehicle suspension kinetic energy recovery system according to applicant&#39;s invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0044]    In the following description of the invention, like numerals and characters designate like elements throughout the figures of the drawings. 
         [0045]    Referring generally to the drawings and more particularly to  FIG. 1 , a vehicle suspension kinetic energy recovery system  20  (See  FIG. 2 ), also referred to sometimes herein as a converter, is adapted to receive energy in the form of kinetic energy from the movement of a vehicle suspension (Step  22 ) and convert that kinetic energy to energy which can be used in the operation of the vehicle (Step  24 ). In Step  26 , the converted energy is stored. In step  28 , the stored energy is used in the operation of the vehicle. 
         [0046]    Still referring to  FIG. 1 , the conversion step  22  can be accomplished using a hydraulic pump mounted between the vehicle&#39;s frame and the vehicle&#39;s suspension as indicated in box  30  (See  FIGS. 2-8 ). The conversion step  22  can also be accomplished using a generator mounted between the frame and suspension of the vehicle, as indicated in box  32  (See  FIG. 9 ). The conversion step  22  can be accomplished using a hydraulic pump and a generator at the same time as indicated in box  34 . Finally, the conversion step  22  can be accomplished using an air compressor as indicated in box  35 . 
         [0047]    Referring still to  FIG. 1 , the energy recovered during the conversion step  22  is stored in a hydraulic system accumulator if the conversion is achieved using a hydraulic pump, as indicated in box  36 . The recovered energy is stored in one or more storage batteries if the conversion is achieved using a generator, as indicated in box  38 . When both a hydraulic pump and a generator are used to recover the kinetic energy associated with the movement of the vehicle suspension, the energy will be stored in both a hydraulic system accumulator and one or more storage batteries, as indicated in box  40 . Recovered energy can also be stored as compressed air in a pressure tank as indicated in box  41 . 
         [0048]    Referring still to  FIG. 1 , the uses of the stored energy captured by the vehicle suspension kinetic energy recovery system of the present invention are limitless. The stored energy from the high pressure accumulator can power hydraulic motors and other hydraulic devices, as indicated in box  42 , and energy stored in the batteries can power electric motors and other electrical devices, as indicated in box  44 . Box  46  illustrates the use of both forms of stored energy. Finally the stored energy from the pressure tank is used to operate pneumatically powered devices. 
         [0049]    Referring now to  FIG. 2 , a hydraulic vehicle suspension kinetic energy recovery system  20  is deployed between the frame F and the suspension S of a vehicle. It will be understood by one skilled in the art that the vehicle suspension kinetic energy recovery system  20  can be deployed between the frame F and the suspension S at any convenient location. It will be further Understood by one skilled in the art that one or more vehicle suspension kinetic energy recovery systems  20  can be used on a single vehicle. 
         [0050]    The hydraulic vehicle suspension kinetic energy recovery system  20  shown in  FIG. 2  is similar to a conventional hydraulic ram. Whereas a conventional hydraulic ram uses high pressure hydraulic fluid from a hydraulic system accumulator to actuate the hydraulic ram, however, kinetic energy associated with the movement of the frame F relative to the suspension S along arrow  52  causes a piston  54  to transfer hydraulic fluid  56  within a cylinder  58  to a hydraulic system high-pressure accumulator (not shown). The piston  54  has a stem  60  which extends upwardly from one end  62  of the cylinder  58  and terminates in a swivel eye  64 . The swivel eye  64  of the piston stem  60  is secured within a U-shaped bracket  66  attached to the frame F by a bolt-and-nut assembly  68 . A member  70  attached to the other end  72  of the cylinder  58  terminates in a swivel eye  74 . The swivel eye  74  of the member  70  is secured within a U-shaped bracket  76  attached to the suspension S by a bolt-and-nut assembly  78 . Using terminology common to shock absorbers, the swivel eye  64  is an “upper mount” which attaches to the frame F, and the swivel eye  74  is a “lower mount” which attaches to the suspension S. 
         [0051]    Still referring fo  FIG. 2 , the piston  54  has a head  80  which moves up and down along arrow  82  within the cylinder  58  as the frame F and the suspension S move alternately closer together and farther apart along the arrow  52  as a result of roadway irregularities. The position of the piston head  80  within the cylinder  58  defines a hydraulic fluid cavity  84  below the piston head  80  and an open cavity  86  above the piston head  80 . An inlet conduit  88  provides one-way flow of hydraulic fluid  56  from a low-pressure reservoir (not shown) to the hydraulic fluid cavity  84 , and an outlet conduit  90  provides one-way flow of the hydraulic fluid  56  from the hydraulic fluid cavity  84  to the high-pressure accumulator (not shown). The vehicle suspension kinetic energy recovery system  20  shown in  FIG. 2  is illustrated when the vehicle is at rest, resulting in an at-rest distance  92  between the frame F and the suspension S. 
         [0052]    It will be understood by one skilled in the art that the vehicle suspension kinetic energy recovery system  20  is, essentially, a positive-displacement piston pump. As the frame F and the suspension S move closer together along the arrow  52  (i.e., in a compression cycle), the vehicle suspension kinetic energy recovery system  20  charges the high-pressure hydraulic accumulator with hydraulic fluid  56  through the outlet conduit  90 . As the frame F and the suspension move farther apart along the arrow  52  in an extension cycle, the vehicle suspension kinetic energy recovery system  20  pulls hydraulic fluid  56  from the low-pressure hydraulic fluid reservoir into the cavity  84  through the inlet conduit  88 . It will be further understood that appropriate sealing rings are required between the piston head  80  and the interior surface of the cylinder  58 . Thus the vehicle suspension kinetic energy recovery system  20  shown in  FIG. 2  functions as a high pressure hydraulic pump wherein the compression cycle produces to a discharge stroke and the extension cycle produces a suction stroke. Because hydraulic cylinders and hydraulic pumps are well known in the art, the details of the sealing rings and other hydraulic cylinder components have been omitted for the sake of clarity. The appropriate use of check valves to achieve one-way flow is also well known in the art. 
         [0053]    Referring now to  FIGS. 3-5 , operation of the vehicle suspension kinetic energy recovery system  20  during a compression cycle, i.e., when a roadway irregularity causes the frame F to move toward the suspension S, begins with the vehicle suspension kinetic energy recovery system  20  in the at-rest position ( FIG. 5 ) and the frame F a distance  92  from the suspension S. In  FIG. 4 , the frame F is shown at relatively shorter distance  94  from the suspension S and the piston head  80  has moved along arrow  82  toward the bottom of the cylinder  58 . During the compression cycle, the piston  54  forces hydraulic fluid  56  from the hydraulic fluid cavity  84  through the outlet conduit  90  to the high-pressure accumulator. In the event the roadway irregularity causes the frame F to move further toward the suspension S along arrow  52 , as shown in  FIG. 5 , the piston  54  moves further toward the bottom of the cylinder  58  along arrow  82  and forces additional hydraulic fluid  56  from the cavity  84  through the outlet conduit  90  to the high-pressure accumulator. 
         [0054]    It will be understood by one skilled in the art that the compression cycle described in  FIGS. 3-5  converts kinetic energy from movement of the suspension S with respect to the frame F to useful energy stored in the high-pressure accumulator. 
         [0055]    Still referring to  FIGS. 3-5 , when the frame F returns to the at-rest position shown in  FIGS. 2 and 3 , the piston  80  moves upward along arrow  82  within the cylinder  58  and pulls hydraulic fluid  56  into the cavity  84  from the low-pressure hydraulic fluid reservoir (not shown) through the inlet conduit  88 . Thus the compression cycle produces a discharge stroke from the vehicle suspension kinetic energy recovery system  20 . 
         [0056]    Referring now to  FIGS. 6-8 , operation of the vehicle suspension kinetic energy recovery system  20  during an extension cycle, i.e., when a roadway irregularity causes the frame F to move away from the suspension S along arrow  52 , begins with the vehicle suspension kinetic energy recovery system  20  in the at-rest position ( FIG. 6 ) and the frame F at the rest-position distance  92  from the suspension S. In  FIG. 7 , the frame F is shown at relatively greater distance  98  from the suspension S and the piston head  80  has moved along arrow  82  toward the top of the cylinder  58 . During this suction stroke of the piston  54 , hydraulic fluid  56  is pulled into the cavity  84  through the inlet conduit  88  from the low-pressure reservoir (not shown). In the event the roadway irregularity causes the frame F to move still farther away from the suspension S along arrow  52 , as shown in  FIG. 8 , the piston  54  moves further toward the top of the cylinder  58  along arrow  82  and additional hydraulic fluid  56  is pulled into the cavity  84  through the inlet conduit  88  from the low-pressure reservoir. 
         [0057]    Still referring to  FIGS. 6-8 , when the frame F returns to the at-rest position shown in  FIGS. 6 ,  2  and  3 , the piston  80  moves downward along arrow  82  within the cylinder  58  and forces hydraulic fluid  56  from the cavity  84  to the high-pressure accumulator (not shown) through the outlet conduit  90 . 
         [0058]    It will be understood by one skilled in the art that return of the vehicle suspension kinetic energy recovery system  20  to the at-rest position from the extension cycle described in  FIGS. 6-8  results in the conversion of kinetic energy from movement of the suspension S with respect to the frame F to useful energy stored in the high-pressure accumulator. Thus, any movement of the frame F relative to the suspension S along arrow  52  results in the capture of kinetic energy for use in powering vehicle systems. Thus the extension cycle produces a suction stroke by the vehicle suspension kinetic energy recovery system  20 . 
         [0059]    Referring now to  FIG. 9 , another vehicle suspension kinetic energy recovery system  120  is deployed between the frame F and the suspension S of a vehicle. It will be understood by one skilled in the art that the vehicle suspension kinetic energy recovery system  120  can be deployed between the frame F and the suspension S at any convenient location. It will be further understood by one skilled in the art that one or more vehicle suspension kinetic energy recovery systems  120  can be used on a single vehicle. 
         [0060]    Still referring to  FIG. 9 , the vehicle suspension kinetic energy recovery system  120  uses the movement of the frame F relative to the suspension S along arrow  152  to cause a magnet assembly  154  to move vertically to create a moving magnetic field. The magnet assembly  154  has a supporting stem  160  which extends upwardly from one end  162  of the cylinder  158  and terminates in a swivel eye  164 , also sometimes referred to as an upper mount. The swivel eye  164  of the supporting stem  160  is secured within a U-shaped bracket  166  attached to the frame F by a bolt-and-nut assembly  168 . A member  170  attached to the other end  172  of the cylinder  158  terminates in a swivel eye  174 , also sometimes referred to as a lower mount. The swivel eye  174  of the member  170  is secured within a U-shaped bracket  176  attached to the suspension S by a bolt-and-nut assembly  178 . 
         [0061]    Still referring fo  FIG. 9 , the supporting stem  154  supports a permanent magnet  180  which moves up and down along arrow  182  within the cylinder  158  as the frame F and the suspension S move alternately closer together and farther apart along the arrow  152  as a result of roadway irregularities. The permanent magnet  180  moves within the cylinder  158  between coils  184  wrapped around coil supporting members  186 . The vehicle suspension kinetic energy recovery system  120  shown in  FIG. 9  is illustrated when the vehicle is at rest, resulting in an at-rest distance  192  between the frame F and the suspension S. 
         [0062]    It will be understood by one skilled in the art that the vehicle suspension kinetic energy recovery system  120  is, essentially, a generator. As the frame F and the suspension S move closer together along the arrow  152  in a compression cycle, the vehicle suspension kinetic energy recovery system  120  charges storage batteries (not shown) with electricity for use in powering vehicle electrical systems. As the frame F and the suspension move farther apart along the arrow  152  in an extension cycle, the vehicle suspension kinetic energy recovery system  120  again charges storage batteries (not shown) with electricity for use in powering vehicle electrical systems. It will be further understood that appropriate auxiliary devices such as commutators may be required. Because generators are well known in the art, the details of the electrical system beyond the vehicle suspension kinetic energy recovery system  120  have been omitted for the sake of clarity. 
         [0063]    Referring now to  FIG. 10 , another hydraulic vehicle suspension kinetic energy recovery system  220  is deployed between the frame F and the suspension S of a vehicle. It will be understood by one skilled in the art that the vehicle suspension kinetic energy recovery system  220  can be deployed between the frame F and the suspension S at any convenient location. It will be further understood by one skilled in the art that one or more vehicle suspension kinetic energy recovery systems  220  can be installed on a single vehicle. 
         [0064]    The hydraulic vehicle suspension kinetic energy recovery system  220  shown in  FIG. 10  is similar to a conventional hydraulic ram. Whereas a conventional hydraulic ram uses high pressure hydraulic fluid from a hydraulic system accumulator to actuate the hydraulic ram, however, kinetic energy associated with the movement of the frame F relative to the suspension S along arrow  252  causes a piston  254  to transfer hydraulic fluid  256  within a cylinder  258  to a hydraulic system high-pressure accumulator (not shown). The piston  254  has a stem  260  which extends upwardly from one end  262  of the cylinder  258  and terminates in a swivel eye  264 . The swivel eye  264  of the piston stem  260  is secured within a U-shaped bracket  266  attached to the frame F by a bolt-and-nut assembly  268 . A member  270  attached to the other end  272  of the cylinder  258  terminates in a swivel eye  274 . The swivel eye  274  of the member  270  is secured within a U-shaped bracket  276  attached to the suspension S by a bolt-and-nut assembly  278 . 
         [0065]    Still referring fo  FIG. 10 , the piston  254  has a head  280  which moves up and down along arrow  282  within the cylinder  258  as the frame F and the suspension S move alternately closer together (in a compression cycle) and farther apart (in an extension cycle) along the arrow  252  as a result of roadway irregularities. The position of the piston head  280  within the cylinder  258  defines a hydraulic fluid cavity  284  below the piston head  280  and an open cavity  286  above the piston head  280 . An inlet conduit  288  provides one-way flow of hydraulic fluid  256  from a low-pressure reservoir (not shown) to the hydraulic fluid cavity  284 . A series of one-way outlet conduits  290 ,  294 , and  298  provide one-way flow of the hydraulic fluid  256  from the hydraulic fluid cavity  284  to the high-pressure accumulator (not shown) through progressively restrictive conduit orifices  292 ,  296 , and  300 , respectively. The vehicle suspension kinetic energy recovery system  220  shown in  FIG. 10  is illustrated when the vehicle is at rest, resulting in an at-rest distance  302  between the frame F and the suspension S. 
         [0066]    Still referring to  FIG. 10 , a suspension coil spring  304  is also deployed between the frame F and the suspension S. One end of the suspension coil spring  304  is secured to the frame F by clips  306 , and the other end of the suspension coil spring  304  is secured to the suspension S by clips  306 . The suspension coil spring  304  is of sufficient size to encompass the cylinder  258  disposed within the coils  304   a,    304   b,    304   c  of the suspension coil spring  304 . It will be understood by on skilled in the art that the suspension coil spring  304  represented herein is well known in the art and the number of coils  304   a,    304   b,  and  304   c  is for illustration only and not intended to be a precise representation of the number of coils in a state-of-the art suspension coil spring. 
         [0067]    The vehicle suspension kinetic energy recovery system  220  shown in  FIG. 10 , like the vehicle suspension kinetic energy recovery systems  20  and  120  described above, charges a high-pressure hydraulic accumulator (now shown) with hydraulic fluid  256  as the frame F and the suspension S move closer together along the arrow  252 . The inclusion of progressively restrictive conduit orifices  292 ,  296 ,  300  in the one-way outlet conduits  290 ,  294 ,  298 , together with the deployment of the suspension coil spring  304 , makes the vehicle suspension kinetic energy recovery system  220  a part of the vehicle suspension system as well. To illustrate the multifunction aspects of the vehicle suspension kinetic energy recovery system  200  of  FIG. 10 , we will describe the vehicle suspension kinetic energy recovery system  200  in operation. 
         [0068]    Still referring to  FIG. 10 , as the frame F moves toward the suspension S along the arrow  252  due to roadway irregularities, the suspension coil spring  304  provides a progressive resistance against further compression. Simultaneously, the piston head  280  moves downwardly within the cylinder  258  towards the suspension S, thereby forcing the hydraulic fluid  256  from the cavity  284 , through the one-way outlet conduits  290 ,  294 , and  298  to the hydraulic accumulator (not shown). The orifice  292  in the one-way outlet conduit  290  is larger than the orifice  296  in the one-way outlet conduit  294 , and the orifice  300  in the one-way outlet conduit  298  is smaller (i.e., more restrictive) than the orifice  296  in the one-way outlet conduit  294 . Thus the hydraulic fluid  256 , at the beginning of the compression of the frame F toward the suspension S, flows to the hydraulic accumulator preferentially through the one-way outlet conduit  290 . 
         [0069]    Still referring to  FIG. 10 , as the frame F moves further downwardly along the arrow  252  toward the suspension S, the piston  280  will eventually move downwardly past the level of the one-way outlet conduit  290 , as indicated by a reference line  308 . The suspension coil spring  304  provides increasing resistance. After the piston  280  moves downwardly past the level of the one-way outlet conduit  290 , the hydraulic fluid  256  is forced from the progressively smaller cavity  284  to the hydraulic accumulator through one-way outlet conduits  294  and  298 . Thus the reduced capacity of the one-way outlet conduits  294 ,  298  to move the hydraulic fluid  256  from the cavity  284  to the hydraulic accumulator—as compared to the combined capacity of one-way outlet conduits  290 ,  294 , and  298 —provides additional resistance to further compression of the frame F toward the suspension S. Thus the vehicle suspension kinetic energy recovery system  220  functions as a high pressure hydraulic pump. The compression cycle produces a discharge stroke, and the extension cycle produces a suction stroke. 
         [0070]    Still referring to  FIG. 10 , as the frame F moves further downwardly along the arrow  252  toward the suspension S, the piston  280  will, at some point move downwardly past the level of the one-way outlet conduit  294 , as indicated by a reference line  310 . The suspension coil spring  304  will continue to provide increasing resistance. After the piston  280  moves downwardly past the level of the one-way outlet conduit  294 , the hydraulic fluid  256  is forced from the progressively smaller cavity  284  to the hydraulic accumulator through the one-way outlet conduit  298 . The reduced capacity of the one-way outlet conduit  298 , to move the hydraulic fluid  26  from the cavity  284  to the hydraulic accumulator—as compared to the combined capacity of one-way outlet conduits  294  and  298 —provides additional resistance to further compression of the frame F toward the suspension S. 
         [0071]    Still referring to  FIG. 10 , as the frame F moves further downwardly along the arrow  252  toward the suspension S, the piston  280  will, at some point move downwardly past the level of the one-way outlet conduit  298 , as indicated by a reference line  312 . The suspension coil spring  304  will continue to provide increasing resistance. At the point the piston  280  moves downwardly past the level of the one-way outlet conduit  298 , the hydraulic fluid  256  becomes trapped in a closed cavity having no outlet. Thus no further movement of the frame F toward the suspension S is permitted. 
         [0072]    It will be understood by one skilled in the art that the vehicle suspension kinetic energy recovery system  220  shown in  FIG. 10  replaces the existing shock absorbers and/or struts, thereby stabilizing the operation of the vehicle while converting kinetic energy associated with movement of the suspension to energy for powering the vehicle and vehicle systems. In vehicle dynamics terminology, the suspension coil spring  304  absorbs energy and the conversion of kinetic energy to high pressure hydraulic fluid energy dissipates energy. 
         [0073]    Referring now to  FIG. 11 , a hydraulic vehicle suspension kinetic energy recovery system  320  is deployed between the frame F and the suspension S of a vehicle. Kinetic energy associated with the movement of the frame F relative to the suspension S along arrow  32  causes a piston  354  to transfer hydraulic fluid  356  within a cylinder  358  to a hydraulic system high-pressure accumulator (not shown). The piston  354  has a stem  360  which extends upwardly from one end  362  of the cylinder  358  and terminates in a swivel eye  364 . The swivel eye  364  of the piston stem  360  is secured within a U-shaped bracket  366  attached to the frame F by a bolt-and-nut assembly  368 . A member  370  attached to the other end  372  of the cylinder  358  terminates in a swivel eye  374 . The swivel eye  374  of the member  370  is secured within a U-shaped bracket  376  attached to the suspension S by a bolt-and-nut assembly  378 . 
         [0074]    Still referring fo  FIG. 11 , the piston  354  has a head  380  which moves up and down along arrow  382  within the cylinder  358  as the frame F and the suspension S move alternately closer together and farther apart along the arrow  352  as a result of roadway irregularities. The position of the piston head  380  within the cylinder  358  defines a lower hydraulic fluid cavity  384  below the piston head  380  and an upper hydraulic fluid cavity  386  above the piston head  380 . An inlet conduit  388  provides one-way flow of hydraulic fluid  356  from a low-pressure reservoir (not shown) to the lower hydraulic fluid cavity  384 , and an outlet conduit  390  provides one-way flow of the hydraulic fluid  356  from the lower hydraulic fluid cavity  384  to the high-pressure accumulator (not shown). The vehicle suspension kinetic energy recovery system  320  shown in  FIG. 11  is illustrated when the vehicle is at rest, resulting in an at-rest distance  392  between the frame F and the suspension S. An inlet conduit  392  provides one-way flow of hydraulic  356  from the low-pressure reservoir (not shown) to the upper hydraulic fluid cavity  386 , and an outlet conduit  394  provides one-way flow of the hydraulic fluid  356  from the upper hydraulic fluid cavity  386  to the high-pressure accumulator (not shown). 
         [0075]    It will be understood by one skilled in the art that the vehicle suspension kinetic energy recovery system  320  is, essentially, a double-action positive-displacement piston pump. As the frame F and the suspension S move closer together along the arrow  352  due to roadway irregularities, the piston  354  of the vehicle suspension kinetic energy recovery system  320  charges the high-pressure hydraulic accumulator with hydraulic fluid  356  through the one-way outlet conduit  390  in the lower hydraulic fluid cavity  384  (a discharge stroke). At the same time, the piston  354  pulls hydraulic fluid  356  into the upper hydraulic fluid cavity  386  through the one-way inlet conduit  392  (a suction stroke). As the frame F and the suspension S move apart along the arrow  352  due to roadway irregularities, the piston  354  charges the high-pressure hydraulic accumulator with hydraulic fluid  356  through the one-way outlet conduit  394  in the upper hydraulic fluid cavity  386  (a discharge stroke). Simultaneously, the piston  354  pulls hydraulic fluid  356  into the lower hydraulic fluid cavity  384  through the one-way inlet conduit  388  (a suction stroke). As a result, any movement of the frame F toward or away from the suspension S result in conversion of kinetic energy to useful energy in the form of high-pressure hydraulic fluid stored in the high-pressure accumulator. 
         [0076]    Referring now to  FIG. 12 , a hydraulic vehicle suspension kinetic energy recovery system  420  is deployed between the frame F and the suspension S of a vehicle. As the vehicle travels along a roadway, irregularities in the roadway cause the frame F to move with respect to the suspension S along arrow  452 . One end of an elongated support member  454  is rigidly attached to the top end  455  of an upper cylinder  458 . The other end of the elongated support member  454  terminates in a swivel eye  460 . The swivel eye  460  is secured within a U-shaped bracket  462  attached to the frame F by a bolt-and-nut assembly  464 . One end of a second elongated Support member  454  is rigidly attached to the bottom end  466  of a lower cylinder  468 . The other end of the second elongated support member  454  terminates in a swivel eye  470 . The swivel eye  470  of the second elongated support member  454  is secured within a U-shaped bracket  472  attached to the suspension S by a bolt-and-nut assembly  474 . 
         [0077]    Still referring fo  FIG. 12 , a double-headed piston  476  has two heads  478 ,  480  connected by a piston stem  482 . One head  478  of the double-headed piston  476  is positioned within the upper cylinder  458  and defines an upper cylinder hydraulic fluid cavity  484  above the piston head  478  and an open cavity  486  below the piston head  478 . An inlet conduit  488  provides one-way flow of hydraulic fluid  456  from a low-pressure reservoir (not shown) to the hydraulic fluid cavity  484 , and an outlet conduit  490  provides one-way flow of the hydraulic fluid  456  from the hydraulic fluid cavity  484  to the high-pressure accumulator (not shown). The other head  480  of the double-headed piston  476  is positioned within the lower cylinder  468  and defines a lower cylinder hydraulic fluid cavity  494  below the piston head  480  and an open cavity  496  above the piston head  480 . 
         [0078]    The vehicle suspension kinetic energy recovery system  420  shown in  FIG. 12  is illustrated when the vehicle is at rest, resulting in an at-rest distance  498  between the frame F and the suspension S 
         [0079]    Still referring to  FIG. 12 , as the frame F and the suspension S move closer together along the arrow  452  in a compression cycle, the piston head  478  is forced upwardly toward the frame F within the upper cylinder  458  along arrow  500 , thereby charging a high-pressure hydraulic accumulator (not shown) with hydraulic fluid  456  through a one-way outlet conduit  490  (a discharge stroke). Simultaneously, the piston head  480  is forced downwardly in the direction of the suspension S within the lower cylinder  468  along arrow  502 , thereby further charging the high-pressure accumulator with hydraulic Fluid  456  through a one-way outlet conduit  510  (a discharge stroke). 
         [0080]    As the frame F and the suspension S move farther apart along the arrow  452  in an extension cycle, the piston head  478  is forced downwardly toward the suspension S within the upper cylinder  458  along arrow  504 , thereby pulling hydraulic fluid  456  from a low-pressure hydraulic fluid reservoir into the cavity  484  through a one-way inlet conduit  488  (a suction stroke). Simultaneously, the piston head  480  is forced upwardly in the direction of the frame F within the lower cylinder  468  along arrow  506 , thereby pull hydraulic fluid from a low-pressure hydraulic fluid reservoir into the cavity  494  through a one-way inlet conduit  508  (a suction stroke). 
         [0081]    It will be understood that appropriate sealing rings are required between the piston heads  478 ,  480  and the interior surfaces of the cylinders  458 ,  468 , respectively. Because the structure of pumps and hydraulic cylinders is well known in the art, the details of the sealing rings and other components have been omitted for the sake of clarity. 
         [0082]    Referring now to  FIG. 13 , a hydraulic vehicle suspension kinetic energy recovery system  520  is deployed between the frame F and the suspension S of a vehicle. Kinetic energy associated with the movement of the frame F relative to the suspension S along arrow  552  causes a piston  554  to transfer hydraulic fluid  556  within a cylinder  558  to a hydraulic system high-pressure accumulator (not shown). The piston  554  has a stem  560  which extends upwardly from one end  562  of the cylinder  558  and terminates in a swivel eye  564 . The swivel eye  564  of the piston stem  560  is secured within a U-shaped bracket  566  attached to the frame F by a bolt-and-nut assembly  568 . A member  570  attached to the other end  572  of the cylinder  558  terminates in a swivel eye  574 . The swivel eye  574  of the member  570  is secured within a U-shaped bracket  576  attached to the suspension S by a bolt-and-nut assembly  578 . 
         [0083]    Still referring fo  FIG. 13 , the piston  554  has a head  580  which moves up and down along arrow  582  within the cylinder  558  as the frame F and the suspension S move alternately closer together and farther apart along the arrow  552  as a result of roadway irregularities. The position of the piston head  580  within the cylinder  558  defines a hydraulic fluid cavity  584  below the piston head  580  and an open cavity  586  above the piston head  580 . An inlet conduit  588  provides one-way flow of hydraulic fluid  556  from a low-pressure reservoir (not shown) to the hydraulic fluid cavity  584 , and an outlet conduit  590  provides one-way flow of the hydraulic fluid  556  from the hydraulic fluid cavity  584  to the high-pressure accumulator (not shown). The vehicle suspension kinetic energy recovery system  520  shown in  FIG. 13  is illustrated when the vehicle is at rest, resulting in an at-rest distance  592  between the frame F and the suspension S. 
         [0084]    Still referring to  FIG. 13 , a suspension coil spring  594  disposed within the hydraulic fluid cavity  584  resists compression of the frame F toward the suspension S. It will be understood by one skilled in the art that the energy vehicle suspension kinetic energy recovery system  520  of  FIG. 13  performs the function of a shock absorber as well as converting kinetic energy associated with suspension motion to useful energy. Thus the energy vehicle suspension kinetic energy recovery system  520  can be deployed between the frame F and the suspension S as a shock absorber. During the compression cycle, hydraulic fluid  556  is forced from the hydraulic fluid cavity  584  through the outlet conduit  590  to the high-pressure accumulator (not shown) in a discharge stroke. During the extension cycle, hydraulic fluid  556  is pulled into the hydraulic fluid cavity  584  through the inlet conduit  588  from a low pressure hydraulic fluid reservoir (not shown) in a suction stroke. 
         [0085]    Referring now to  FIG. 14 , a hydraulic vehicle suspension kinetic energy recovery system  620  is deployed between the frame F and the suspension S of a vehicle. One end of an elongated support member  654  is rigidly attached to the top end  655  of an upper cylinder  658 . The other end of the elongated support member  654  terminates in a swivel eye  660 . The swivel eye  660  is secured within a U-shaped bracket  662  attached to the frame F by a bolt-and-nut assembly  664 . One end of a second elongated support member  654  is rigidly attached to the bottom end  666  of a lower cylinder  668 . The other end of the second elongated support member  654  terminates in a swivel eye  670 . The swivel eye  670  of the second elongated support member  654  is secured within a U-shaped bracket  672  attached to the suspension S by a bolt-and-nut assembly  674 . 
         [0086]    Still referring fo  FIG. 14 , a double-headed piston  676  has two heads  678 ,  680  connected by a common piston stem  682 . One head  678  of the double-headed piston  676  is positioned within the upper cylinder  658  and defines an upper cylinder hydraulic fluid cavity  684  above the piston head  678  and an open cavity  686  below the piston head  678 . An inlet conduit  688  provides one-way flow of hydraulic fluid  656  from a low-pressure reservoir (not shown) to the hydraulic fluid cavity  684 , and an outlet conduit  690  provides one-way flow of the hydraulic fluid  656  from the hydraulic fluid cavity  684  to the high-pressure accumulator (not shown). The other head  680  of the double-headed piston  676  is positioned within the lower cylinder  668  and defines a lower cylinder hydraulic fluid cavity  694  below the piston head  680  and an open cavity  696  above the piston head  680 . 
         [0087]    The vehicle suspension kinetic energy recovery system  620  shown in  FIG. 14  is illustrated when the vehicle is at rest, resulting in an at-rest distance  698  between the frame F and the suspension S. A set of return coil springs  812  is disposed within the hydraulic fluid cavity  684  of the upper cylinder  658 , and a second set of return coil springs  814  is disposed within the hydraulic fluid cavity  694  of the lower cylinder  668 . 
         [0088]    Still referring to  FIG. 14 , as the frame F and the suspension S move closer together along the arrow  652 , the piston head  678  is forced upwardly toward the frame F within the upper cylinder  658  along arrow  700 , thereby charging a high-pressure hydraulic accumulator (not shown) with hydraulic fluid  656  through the one-way outlet conduit  690 . Simultaneously, the piston head  680  is forced downwardly in the direction of the suspension S within the lower cylinder  668  along arrow  702 , thereby further charging the high-pressure accumulator with hydraulic fluid  756  through a one-way outlet conduit  810 . Thus the compression cycle, wherein the piston heads  678 ,  680  move toward the closed ends  655 ,  666  of the cylinders  658 ,  668 , respectively, produces a discharge stroke. 
         [0089]    As the frame F and the suspension S move farther apart along the arrow  652 , the piston head  678  is forced downwardly toward the suspension S within the upper cylinder  658  along arrow  704 , thereby pulling hydraulic fluid  656  from a low-pressure hydraulic fluid reservoir into the cavity  684  through a one-way inlet conduit  688 . Simultaneously, the piston head  680  is forced upwardly in the direction of the frame F within the lower cylinder  668  along arrow  706 , thereby pulling hydraulic fluid from a low-pressure hydraulic fluid reservoir into the cavity  694  through a one-way inlet conduit  708 . Thus the extension cycle, wherein the return coil springs  712 ,  714  force the piston heads  678 ,  680  away from the closed ends  655 ,  666  of the cylinders  658 ,  668 , respectively, produces a suction stroke. 
         [0090]    It will be understood that appropriate sealing rings are required between the piston heads  678 ,  680  and the interior surfaces of the cylinders  658 ,  668 , respectively. Because the structure of pumps and hydraulic cylinders is well known in the art, the details of the sealing rings and other components have been omitted for the sake of clarity. 
         [0091]    Still referring to  FIG. 14 , the return coil springs  712  disposed within the hydraulic fluid cavity  684  of the upper cylinder  658  and the return coil springs  714  disposed within the hydraulic fluid cavity  694  of the lower cylinder  668  resist compression of the frame F in the direction of the suspension S, thereby making the vehicle suspension kinetic energy recovery system  620  shown in  FIG. 14  suitable for use as a shock absorber in a vehicle suspension. 
         [0092]    Referring now to  FIG. 15 , a vehicle suspension kinetic energy recovery system  720  is deployed between the frame F and the suspension S of a vehicle. It will be understood by one skilled in the art that the vehicle suspension kinetic energy recovery system  720  can be deployed between the frame F and the suspension S at any convenient location. It will be further understood by one skilled in the art that one or more vehicle suspension kinetic energy recovery system  720  devices can be used on a single vehicle. Kinetic energy associated with the movement of the frame F toward the suspension S along arrow  752  is used to transfer (i.e., to pump) hydraulic fluid to a hydraulic system high-pressure accumulator (not shown). 
         [0093]    Still referring fo  FIG. 15 , an upper cylinder  754  is rigidly attached at a closed end  755  to the suspension S, and the other end  758  of the upper cylinder  754  is open. An upper piston head  760  is positioned within the upper cylinder  754  within an upper cylinder hydraulic fluid cavity  762 . An inlet conduit  766  provides one-way flow of hydraulic fluid  756  from a low-pressure reservoir (not shown) to the upper cylinder hydraulic fluid cavity  762 , and an outlet conduit  768  provides one-way flow of the hydraulic fluid  756  from the upper cylinder hydraulic fluid cavity  762  to a high-pressure accumulator (not shown). Piston head guides  770  maintain alignment of the upper piston head  760  within the upper cylinder  754 . Return coil springs  781  disposed within the upper cylinder hydraulic fluid cavity  762  bias the piston head  760  away from the closed end  755  of the upper cylinder  754  when the vehicle is in the at-rest position shown in  FIG. 15 . A retaining ring  783  retains the piston head  760  within the upper cylinder hydraulic fluid cavity  762 . 
         [0094]    Still referring fo  FIG. 15 , a lower cylinder  772  is rigidly attached at one closed end  774  to the suspension S. The other end  776  of the lower cylinder  772  is open. A lower piston head  778  is positioned within the lower cylinder hydraulic fluid cavity  780 . An inlet conduit  784  provides one-way flow of hydraulic fluid  756  from a low-pressure reservoir (not shown) to the lower cylinder hydraulic fluid cavity  780 , and an outlet conduit  786  provides one-way flow of the hydraulic fluid  756  from the lower cylinder hydraulic fluid cavity  780  to the high-pressure accumulator. Piston head guides  788  maintain alignment of the lower piston head  778  within the lower cylinder  772 . Return coil springs  785  disposed within the lower cylinder hydraulic fluid cavity  780  bias the piston head  778  in the at-rest position shown in  FIG. 15 . A retaining ring  787  retains the piston head  778  within the lower cylinder hydraulic fluid cavity  780 . 
         [0095]    The vehicle suspension kinetic energy recovery system  720  shown in  FIG. 15  is illustrated when the vehicle is at rest, resulting in an at-rest distance  790  between the frame F and the suspension S. A suspension coil spring  796  is disposed between the upper piston head  760  and the lower piston head  778 . One end  798  of the suspension coil spring  796  biases the upper cylinder piston head  760  just slightly against the piston head  760  within the upper cylinder hydraulic fluid cavity  764 . The other end  800  of the suspension coil spring  796  biases the lower cylinder piston head  778  just slightly against the piston head  778  within the lower cylinder hydraulic fluid cavity  780 . A protective shroud  802  shields the remaining components of the vehicle suspension kinetic energy recovery system  720  from dirt, dust, debris, and other roadway contaminants. 
         [0096]    It will be understood by one skilled in the art that the suspension coil spring  796  is sized to provide a slight bias against the piston heads  760  and  778  when the frame F and the suspension S are in the at-rest position shown in  FIG. 15 . The return coil springs  781  bias the upper cylinder piston head  760  against one end  798  of the suspension coil spring  796 . The return coil springs  785  bias the lower cylinder piston head  778  against the other end  800  of the suspension coil spring  796 . As the frame F and the suspension S move closer together along the arrow  752 , the suspension coil spring  796  forces the upper cylinder piston head  760  upwardly toward the frame F within the upper cylinder  754  along arrow  792 , thereby charging a high-pressure hydraulic accumulator (not shown) with the hydraulic fluid  756  through the one-way outlet conduit  768 . Simultaneously, the suspension coil spring  796  forces the lower cylinder piston head  778  downwardly in the direction of the suspension S within the lower cylinder  772  along arrow  794 , thereby further charging the high-pressure accumulator with hydraulic fluid  756  through the one-way outlet conduit  786 . 
         [0097]    As the frame F and the suspension S move farther apart along the arrow  752 , the suspension coil spring  796  relaxes and the return coil springs  781  within the upper cylinder hydraulic fluid cavity  762  move the piston head  760  downwardly toward the suspension S within the upper cylinder  754  along arrow  792 , thereby pulling hydraulic fluid  756  from a low-pressure hydraulic fluid reservoir into the upper cylinder hydraulic fluid cavity  784  through the one-way inlet conduit  766  (a suction stroke). Simultaneously, the return coil springs  785  in the lower cylinder hydraulic fluid cavity  780  move the lower cylinder piston head  778  in the direction of the suspension S within the lower cylinder hydraulic fluid cavity  780  along arrow  794 , thereby pulling hydraulic fluid  756  from a low-pressure hydraulic fluid reservoir into the lower cylinder hydraulic fluid cavity  780  through the one-way inlet conduit  784  (a suction stroke). Thus the vehicle suspension kinetic energy conversion system  720  of  FIG. 15  functions as a high pressure hydraulic pump. During the compression cycle, the suspension coil spring  796  moves the pistons  760 ,  778  in a discharge stroke. During the extension cycle, the suspension coil spring  796  relaxes and the return coils springs  781 ,  785  within the hydraulic fluid cavities  762 ,  760 , respectively, move the pistons  760 ,  769  away from the closed ends  758 , in a suction stroke. 
         [0098]    It will be understood by one skilled in the art that the suspension coil spring  796  absorbs a small portion of kinetic energy available from the movement of the suspension S relative to the frame F. The selection of the suspension coil spring  796  affects both the ride of the vehicle and the amount of kinetic energy available to power the pump-like piston-cylinder combinations of the vehicle suspension kinetic energy recovery system  720 . A firmer suspension coil spring  796  will absorb less kinetic energy and provide for more energy recovery, whereas a relatively softer suspension coil spring  796  will absorb more kinetic energy and reduce the amount of energy recovered. It will be further understood by one skilled in the art that the vehicle suspension kinetic energy recovery system  720  shown in  FIG. 15  is suitable for use as a shock absorber. 
         [0099]    As noted above, any convenient number of vehicle suspension kinetic energy recovery systems can be deployed between the frame F and the suspension S of a vehicle. Similarly, the energy recovered from one vehicle, such as the trailer of a tractor-trailer rig can be transferred to another vehicle, such as the tractor of the tractor-trailer rig. For a tractor-trailer rig consisting of a tractor and two trailers, the tractor and both trailers are potential energy-gathering devices wherein the kinetic energy associated with suspension movement is converted to useful energy for use in vehicle systems. 
         [0100]    Referring once again to  FIG. 1 , in light of the disclosures with respect to  FIGS. 2-15 , it will understood by one skilled in the art that an air compressor deployed between the frame F and the suspension S of a vehicle will convert the vehicle suspension kinetic energy to energy in the form of compressed air for use in powering vehicle pneumatic systems. 
         [0101]    The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents.