Patent Publication Number: US-7210430-B2

Title: Rapid response power conversion device

Description:
SPECIFICATION  
     This divisional application claims the benefit of application Ser. No. 10/190,336 filed Jul. 5, 2002 now U.S. Pat. No. 6,957,631 in the United States Patent Office which claims the benefit of application Ser. No. 60/303,053 filed Jul. 5, 2001. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to internal combustion engines. More specifically, the present invention relates to an apparatus and method of extracting energy during combustion in an internal combustion engine. 
     2. Related Art 
     Primary power sources that directly convert fuel into usable energy have been used for many years in a variety of applications including motor vehicles, electric generators, hydraulic pumps, etc. Perhaps the best known example of a primary power source is the internal combustion engine, which converts fossil fuel into rotational power. Internal combustion engines are used by almost all motorized vehicles and many other energetically autonomous devices such as lawn mowers, chain saws, and emergency electric generators. Converting fossil fuels into usable energy is also accomplished in large electricity plants, which supply electric power to power grids accessed by thousands of individual users. While primary power sources have been successfully used to perform these functions, they have not been successfully used independently in many applications because of their relatively slow response characteristics. This limitation is particularly problematic in powering robotic devices and similar systems which utilize a feedback loop which makes real time adjustments in movements of the mechanical structure. Typically, the power source in such a system must be able to generate power output which quickly applies corrective signals to power output as necessary to maintain proper operation of the mechanical device. 
     The response speed of a power source within a mechanical system, sometimes referred to as bandwidth, is an indication of how quickly the energy produced by the source can be accessed by an application. An example of a rapid response power system is a hydraulic pressure system. In a hydraulic system, energy from any number of sources can be used to pressurize hydraulic fluid and store the pressurized fluid in an accumulator. The energy contained in the pressurized fluid can be accessed almost instantaneously by opening a valve in the system and releasing the fluid to perform some kind of work, such as extending or retracting a hydraulic actuator. The response time of this type of hydraulic system is very rapid, on the order of a few milliseconds or less. 
     An example of a relatively slow response power supply system is an internal combustion engine. The accelerator on a vehicle equipped with an internal combustion engine controls the rotational speed of the engine, measured in rotations per minute (“rpms”). When power is desired the accelerator is activated and the engine increases its rotational speed accordingly. But the engine cannot reach the desired change in a very rapid fashion due to inertial forces internal to the engine and the nature of the combustion process. If the maximum rotational output of an engine is 7000 rpms, then the time it takes for the engine to go from 0 to 7000 rpms is a measure of the response time of the engine, which can be a few seconds or more. Moreover, if it is attempted to operate the engine repeatedly in a rapid cycle from 0 to 7000 rpms and back to 0 rpms, the response time of the engine slows even further as the engine attempts to respond to the cyclic signal. In contrast, a hydraulic cylinder can be actuated in a matter of milliseconds or less, and can be operated in a rapid cycle without compromising its fast response time. 
     For this reason, many applications utilizing slow response mechanisms require the energy produced by a primary power source be stored in another, more rapid response energy system which holds energy in reserve so that the energy can be accessed instantaneously. One example of such an application is heavy earth moving equipment, such as backhoes and front end loaders, which utilize the hydraulic pressure system discussed above. Heavy equipment is generally powered by an internal combustion engine, usually a diesel engine, which supplies ample power for the operation of the equipment, but is incapable of meeting the energy response requirements of the various components. By storing and amplifying the power from the internal combustion engine in the hydraulic system, the heavy equipment is capable of producing great force with very accurate control. However, this versatility comes at a cost. In order for a system to be energetically autonomous and be capable of precise control, more components must be added to the system, increasing weight and cost of operation of the system. 
     Another example of a rapid response power supply is an electrical supply grid or electric storage device such as a battery. The power available in the power supply grid or battery can be accessed as quickly as a switch can be opened or closed. A myriad of motors and other applications have been developed to utilize such electric power sources. Stationary applications that can be connected to the power grid can utilize direct electrical input from the generating source. However, in order to use electric power in a system without tethering the system to the power grid, the system must be configured to use energy storage devices such as batteries, which can be very large and heavy. As modern technology moves into miniaturization of devices, the extra weight and volume of the power source and its attendant conversion hardware are becoming major hurdles against meaningful progress. 
     The complications inherent in using a primary power source to power a rapid response source become increasingly problematic in applications such as robotics. In order for a robot to accurately mimic human movements, the robot must be capable of making precise, controlled, and timely movements. This level of control requires a rapid response system such as the hydraulic or electric systems discussed above. Because these rapid response systems require power from some primary power source, the robot must either be part of a larger system that supplies power to the rapid response system or the robot must be directly fitted with heavy primary power sources or electric storage devices. Ideally, however, robots and other applications should have minimal weight, and should be energetically autonomous, not tethered to a power source with hydraulic or electric supply lines. To date, however, technology has struggled to realize this combination of rapid response, minimal weight, effective control, and autonomy of operation. 
     SUMMARY OF THE INVENTION 
     The present invention relates to an apparatus and method for extracting a portion of energy from the energy created during combustion in an internal combustion engine. The present invention is directed to extracting a portion of energy during an optimal time period of combustion and providing superior bandwidth characteristics to the engine. 
     The present invention includes a chamber having a primary piston, a rapid response component and a controller operably interconnected to the chamber. The chamber also includes at least one fluid port for supplying fluid thereto and an out-take port. The primary piston in combination with the fluid port is configured to provide a variable pressure to the chamber and at least partially facilitate combustion to create energy in a combustion portion of the chamber. The primary piston is configured to reciprocate in the chamber. The controller is configured to control the combustion in the chamber. The rapid response component is in fluid communication with the chamber so that the rapid response component is situated adjacent the combustion portion of the chamber. According to the present invention, the rapid response component is configured to draw a portion of the energy from the combustion in the chamber. 
     One aspect of the present invention provides that the portion of energy drawn from the combustion by the rapid response component is drawn from a proximate instant of the combustion and prior to the primary piston being positioned at a median between a top dead center position and a bottom dead center position in the chamber. Furthermore, the rapid response component draws at least 90% of the portion of the energy from the chamber within 45 degrees of the primary piston descending from the top dead center position. As such, a majority of the portion of energy extracted by the rapid response component is completed relatively long before the energy primary piston completes a reciprocation cycle. 
     The rapid response component includes a secondary piston having an energy receiving portion. The secondary piston is interconnected to an energy transferring portion, wherein the energy receiving portion of the secondary piston is configured to draw the portion of the energy from the combustion and transfer such energy to the energy transferring portion of the rapid response component. At the energy transferring portion, the portion of energy extracted from the combustion is converted to any one of hydraulic energy, pneumatic energy, electric energy and mechanical energy. 
     Another aspect of the present invention provides that as the linear movement of the primary piston between the top and dead center positions is always substantially constant, the linear movement of the secondary piston is variable in length. Such variable length is determined by at least a load to which the portion of the energy is acting upon. Furthermore, the mass of the primary piston is greater than the mass of the secondary piston such that a first effective inertia of the primary piston is greater than the second effective inertia of the secondary piston by a ratio of at least 5:1. Such ratio is the case at least during the time in which the portion of energy is being extracted to the secondary piston. 
     The controller is configured to control combustion in the chamber. In particular, depending on the load and/or requirements of the internal combustion engine, the controller is configured to control and select particular cycles for initiating combustion out of the substantially continuously, repeating cycles of the primary piston reciprocating in the chamber. As such, the controller is configured to control the energy extracted by the secondary piston to provide an impulse modulation and/or amplitude modulation of energy. As such, the ability to select particular cycles and, thus, the ability to rapidly provide energy and terminate the energy from cycle to cycle provides superior bandwidth than the bandwidth provided from the primary piston. 
     In a second embodiment, the chamber includes a first compartment and a second compartment with a divider portion dividing the compartments and an aperture defined in the divider portion and extending between the first and second compartments. With this arrangement, the fluid is compressed by the primary piston from the first compartment to the second compartment through the aperture, wherein the controller ignites the compressed fluid in the second compartment. In the second embodiment, the combustion is at least partially isolated from the primary piston. 
     In a third embodiment, the present invention is directed to a rapid response component associated with a non-combustion system. In this system, a reactive member, such as a catalyst, is positioned in the chamber. The reactive member is positioned in the chamber and configured to receive a fluid, such as a monopropellant or hydrogen peroxide, to produce a non-combustive reaction which provides energy and a variable pressure to the chamber for reciprocating the primary piston. The controller is configured to control the non-combustive reaction by controlling the fluid entering the chamber. The rapid response component is situated adjacent a portion of the chamber having the non-combustive reaction so that the rapid response component is configured to draw and extract a portion of the energy for the non-combustive reaction. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates is a schematic side view of a rapid response energy extracting system, depicting a chamber having a primary piston and a secondary piston, according to a first embodiment of the present invention; 
         FIG. 2  illustrates a block diagram associated with various partial schematic side views, depicting various forms of energy transfer through an energy transfer portion of the rapid response energy extracting system, according to the first embodiment of the present invention; 
         FIG. 3  illustrates a partial schematic side view of the rapid response energy extracting system, depicting a chamber having multiple compartments, according to a second embodiment of the present invention; 
         FIG. 4  illustrates a graphical representation of physical response characteristics of the primary piston with respect to the secondary piston in terms of time, temperature and displacement of the primary and secondary pistons, according to the present invention; 
         FIG. 5  illustrates a graphical representation of the physical response characteristics of the primary piston with respect to the secondary piston, depicting impulse modulation of the secondary piston, according to the present invention; 
         FIG. 6  illustrates a graphical representation of the physical response characteristics of the secondary piston, depicting a combination of impulse and amplitude modulation of the secondary piston, according to the present invention; 
         FIG. 7  illustrates a partial schematic side view of the rapid response energy extracting system, depicting the primary and secondary pistons in terms of linear displacement, according to the present invention; 
         FIG. 8  illustrates a partial schematic side view of the rapid response energy extracting system, depicting a non-combustion system, according to a third embodiment of the present invention; and 
         FIG. 9  illustrates an elevation view of a representative use of the present invention, as used in a wearable exoskeleton frame. 
     
    
    
     DETAILED DESCRIPTION 
     For the purposes of promoting an understanding of the principles of the present invention, reference will now be made to the exemplary embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications of the inventive features illustrated herein, and any additional applications of the principles of the invention as illustrated herein, which would occur to one skilled in the relevant art and having possession of this disclosure, are to be considered within the scope of the invention. 
     Referring first to  FIG. 1 , a simplified schematic view of a rapid response energy extracting system  100  is illustrated. Such a system  100  may partially include a typical internal combustion (“IC”) engine, such as a four stroke spark ignition IC engine. Other types of engines may also be utilized with the present invention, such as compression ignition IC engines, two stroke IC engines, non-combustion engines or any other suitable engine. For purposes of simplicity, rapid response energy extracting system  100  is illustrated here in conjunction with a typical four stroke spark ignition IC engine, wherein a single chamber  110  is depicted with the present invention. 
     The chamber  110  is defined by chamber walls  105  and includes one or more intake ports  112  for receiving a fuel  114  and an oxidizer such as air or oxygen, separately or as a mixture, and an out-take port  122  for releasing combustive exhaust gases  124 . Each of the intake port  112  and the out-take port  122  includes a valve (not shown), which are each configured to open and close at specified times to allow fuel  114  and exhaust  124  to enter and exit the chamber  110 , respectively. The chamber  110  includes a primary piston  130 , a secondary piston  140  and a combustion portion  120  therebetween. The primary piston  130  is interconnected to a piston rod  132 , which in turn is interconnected to a crank shaft  134 . The primary piston  130  is sized and configured to move linearly within the chamber  110  for converting linear movement  138  from the primary piston  130  to the crank shaft  134  into rotational energy  136 . Such rotational energy  136  may be used to power a wide range of external applications, such as any type of application that typically utilizes an IC combustion engine. 
     The linear movement  138  of the primary piston  130  takes place between a top dead center (“TDC”) position and a bottom dead center (“BDC”) position. The TDC position occurs when the piston  130  has moved to its location furthest from the crank shaft  134  and the BDC position occurs when the primary piston  130  has moved to its location closest to the crank shaft  134 . The linear movement of the primary piston  130  between the TDC position and the BDC position may be generated by cyclic combustion in the combustion portion  120  of the chamber  110 . Primary piston  130  may also move linearally within chamber  110  by other suitable means, such as electric energy from a battery. 
     A four stroke cycle of an IC engine begins with the piston  130  located at TDC. As the piston  130  moves toward BDC, a fuel  114  is introduced into the chamber  110  through intake port  112 , which may include one or more openings and may also be a variable opening for varying the flow and amount of fuel  114  into the chamber  110 . Once the fuel  114  enters the chamber  110 , the intake port  112  is closed and the piston  130  returns toward TDC, compressing the fuel  114  in the chamber  110 . An ignition source  116 , controlled by a controller  115 , supplies a spark at which point the compressed fuel combusts and drives the piston  130  back to BDC. As the piston  130  returns again toward TDC, combustive exhaust gases  124  are forced through out-take port  122 . The out-take port  122  is then closed, and intake port  112  is opened, and the four stroke cycle may begin again. In this manner, a series of combustion cycles powers the crank shaft  134 , which provides rotational energy  136  to an external application. 
     According to the present invention, chamber  110  also includes a secondary piston  140  having a secondary piston rod  142  extending therefrom. The secondary piston  140  includes a face, or energy receiving end  144 , and the secondary piston rod  142  is coupled to an energy transferring portion  146 . The energy receiving end  144  may be positioned in chamber  110  to face primary piston  130  so that the longitudinal movement of the primary piston  130  and the secondary piston  140  corresponds with a longitudinal axis of chamber  110 . In an inactive position, the energy receiving end  144  of the secondary piston  140  may be biased in a substantially sealing position against a lip or some other suitable sealing means, biased by a spring or by another suitable biasing force, such as a pressure reservoir, so that the secondary piston  140  is biasingly positioned prior to introducing fuel into the combustion chamber  110  or prior to combustion during cyclic combustion of the system  100 . 
     One important aspect of the present invention is that the secondary piston  140  includes a substantially lower mass than that of the primary piston  130 . Such a substantially lower mass positioned adjacent the combustion portion  120  of the chamber  110  facilitates a rapid response to combustion, which provides linear movement  148  along the longitudinal axis of the chamber  110  to the secondary piston  140 . Because the mass of the secondary piston  140  is much lower than a mass of the primary piston  130 , the secondary piston  140  can efficiently extract a large fraction of the energy created by the combustion before it is otherwise lost to inefficiencies inherent in IC engines. With this arrangement, the energy receiving end  144  of the secondary piston  140  is sized, positioned and configured to react to combustion in the chamber  110  so as to provide linear movement  148  to the energy receiving end  144  to then act upon the energy transferring portion  146  of the system  100 . 
     Referring now to  FIG. 2 , the energy transferring portion  146  may include and/or may be coupled with any number of energy conversion devices. In particular, the energy transferring portion  146  is configured to transfer the linear movement of the secondary piston  140  to any one of hydraulic energy, pneumatic energy, electric energy and/or mechanical energy. Transferring linear motion into such various types of energy is well known in the art. 
     For example, in a hydraulic system  160 , linear motion via the secondary piston rod  142  transferred to a hydraulic piston  164  in a hydraulic chamber  162  may provide hydraulic pressure  168 , as well known in the art. Similarly, in a pneumatic system  170 , the secondary piston rod  142  may provide linear motion to a pneumatic piston  174  in a pneumatic chamber  162  to provide output energy in the form of pneumatic pressure. 
     Other systems may include an electrical system  180  and a mechanical system  190 . As well known in the art, in an electrical system  180 , the linear motion of secondary piston rod  142  may be interconnected to an armature with a coil wrapped therearound, wherein the armature reciprocates in the coil to generate an electrical energy output  188 . Furthermore, in the mechanical system, linear motion from secondary piston rod  142  may be transferred to rotational energy  198  with a pawl  192  pushing on a crank shaft  194  to provide rotational energy  198 . Additionally, the secondary piston rod  142  may be directly interconnected to the crank shaft  194  to provide the rotational energy  198 . Other methods of converting energy will be apparent to those skilled in the art. For example, rotational electric generators, gear driven systems, and belt driven systems can be utilized by the energy transferring portion  146  the present invention. 
     Referring now to  FIG. 3 , there is illustrated a second embodiment of the rapid response energy extracting system  200 . The second embodiment is similar to the first embodiment, except the chamber  210  defines a first compartment  254  and a second compartment  256  with a divider portion  250  disposed therebetween. The divider portion  250  defines an aperture  252  therein, which aperture  252  extends between the first compartment  254  and the second compartment  256 . With this arrangement, the primary piston  230  is positioned in the first compartment  254  and the secondary piston  240  is positioned in the second compartment  256 . The intake port  212  allows fuel  214  to enter the first compartment  254 . The fuel  214  is pushed through the aperture  252  from the first compartment  254  into the second compartment  256  via the primary piston  230 . The fuel  214  is compressed at a combustion portion  220  of the chamber  210 , which is directly adjacent the secondary piston  240 . An ignition source  216  then fires the fuel for combustion, wherein the secondary piston  240  moves linearally, as indicated by arrow  248 , with a rapid response to the combustion. The combustive exhaust  224  then exits through the out-take port  222 . 
     In the second embodiment, the primary piston  230  may reciprocate via combustion or an electric power source to push the fuel  214  from the first compartment to the second compartment of chamber  210 . By having a divider portion  250 , the combustion at the combustion portion  220  of the chamber  210  can be at least partially, or even totally, isolated from the primary piston  230 . Depending on the requirements of the system  200 , the controller  215  may be configured to open or close aperture  252  at varying degrees to isolate combustion from the primary piston  230 . As such, in the instance of total isolation, a maximum amount of energy to the secondary piston  240  may be transferred by a rapid response to combustion. 
     Referring now to  FIGS. 1 and 4 , a graphical diagram of the physical response characteristics of the secondary piston  140  with respect to the primary piston  130  is illustrated. Line  330  represents the linear movement  138  of the primary piston  130 , reciprocating between the TDC  350  and the BDC  352  positions thereof. Line  330  illustrates one complete cycle, for a four cycle IC engine, in which the primary piston  130  travels between the TDC  350  and the BDC  352  positions twice, with one combustion event occurring immediately after the primary piston  130  reaches TDC the first time. Line  340  illustrates the linear displacement of the secondary piston  140 . As indicated, the secondary piston  140  reaches substantially full displacement within at least 45 degrees, and even up to 30 degrees, of the primary piston  140  descending from TDC  350 , wherein the secondary piston  140  completes one cycle much more rapidly than does the primary piston  130 . 
     Turning now to line  360 , a relative indication of the temperature rise and fall in the chamber  110  due to combustion and heat loss, respectively, with respect to the linear positions of the primary piston  130  and the secondary piston  140  is shown. Immediately after ignition of the fuel  114 , when the primary piston  130  is proximate the TDC  350  position, combustion facilitates a dramatic increase in temperature. As well known, IC engines are designed to convert the thermal energy created by combustion into linear movement of the primary piston, which is in turn converted into rotational energy in the drive shaft. However, much of the thermal energy created in conventional internal combustion engines is lost due to heat escaping into the engine walls surrounding the combustion chamber and in exhaust gases. Even the most efficient internal combustion engines rarely reach efficiency rates of more than 35%. Consequently, more than half of the energy available from the combusted fuel is lost in the form of heat through the walls and piston via conduction and radiation. 
     The heat rise and heat loss illustrated by the rising and dropping line  360 , representing combustion, depicts the time during which energy is available in the form of thermal energy and the time in which the primary piston  130  should be extracting the thermal energy. Time t 2  indicates the time period during which a majority of the thermal energy is available for conversion by the primary piston. Time t 1  indicates the time period during which the primary piston  130  is moving from the TDC  350  to BDC  352  positions. It is during the period t 1  that the primary piston  130  should be converting energy from the combustion process. As indicated by the difference between the two time periods t 1  and t 2 , most of the thermal energy from the combustion escapes prior to the primary piston  130  reaching a median  354  of its travel between the TDC  350  to BDC  352  positions. 
     However, according to the present invention, the secondary piston  140  substantially completes its useful energy extraction cycle before the expiration of time period t 2 . Because the secondary piston  140  moves much more rapidly than does the primary piston  130 , it can convert a much greater percentage of the thermal energy into linear motion before the thermal energy is lost to the heat sink formed by the walls, primary piston, and other components of the IC engine. Additionally, because the secondary piston  140  acts independently of the primary piston  130  and because the secondary piston  140  has a substantially lower mass than the primary piston, the secondary piston reacts to combustion with a very rapid response time. 
     For example, an IC engine having operating characteristics running at 3000 revolutions per minute, t 1  would be approximately 10 milliseconds, or 0.010 seconds, and t 2  would be approximately 3 milliseconds. Because the secondary piston  140  can be operated independently of the primary piston  130 , the secondary piston  140  can be operated with a response time of approximately 3 milliseconds or potentially even at a shorter response time. In other words, the secondary piston  140  can both begin and stop extracting energy from the combustion cycles of the system  100  within at least a 3 millisecond time period. Faster response times can be achieved by operating the primary piston  130  at a higher rpm state. 
     Turning to  FIGS. 1 and 5 , physical response characteristics, such as impulse modulation and superior bandwidth provided by the secondary piston  140  with respect to the primary piston  130 , are illustrated. In particular, line  430  depicts the primary piston  130  reciprocating repeatedly or substantially continuously with a substantially fixed displacement between the TDC and BDC positions. As the primary piston  130  continuously reciprocates, the controller  115  is configured to control combustion at selective cycles of reciprocation of the primary piston  130 . The reciprocation cycles of the primary piston  130  in which combustion is selected are illustrated in corresponding lines  440 . Lines  440  indicate a portion of energy extracted by the secondary piston  140  from the selected cycles of the primary piston  130  where the controller  115  controls or initiates combustion (i.e., amplitude modulation, impulse modulation, and frequency modulation). The flat portion  442  of line  440  corresponds to the absence of combustion, showing no displacement and energy extraction from the secondary piston  140 . 
     Turning to  FIG. 7 , there is illustrated relative linear movement with respect to the primary piston  630  and the secondary piston each in chamber  610 . In particular, the linear movement  638  of the primary piston  630  in chamber  610  is substantially constant with a displacement D 1 . On the other hand, the linear movement  648  of the secondary piston may be variable in length referenced as displacement D 2 . Such variable length of displacement D 2  of the secondary piston may change with respect to a load  650  of which the energy extracted by the secondary piston is acting upon. Other factors that effect the displacement D 2  of the secondary piston  640  relate to inertia of the mass of secondary piston  640  and its piston rod  642 . As previously set forth, the effective inertia of the primary piston  630 , an a crank assembly is greater than the effective inertia of the secondary piston  640  by a ratio of at least 5:1, and even at least 10:1, at least during the time period when a portion of energy is extracted from combustion by the secondary piston  640 . Since the inertia of the secondary piston  640  is less than the inertia of the primary piston  630 , the secondary piston  640  is able to react with a rapid response. In this manner, the displacement D 2  of the secondary piston  640  is variable in length, in which the displacement D 2  naturally matches and corresponds with at least the load  650  to which the extracted energy is acting upon as well as with respect to the combustion force acting on the secondary piston  640  at combustion. D 2 ′ and D 2 ″ represent a variety of lengths which form a continuum of values, corresponding to a continuous transmission system. This is illustrated in  FIG. 7A , wherein D 2 ′ corresponds to a heavier load, and D 2 ″ relates to a lighter load, thereby eliminating the need for a separate transmission device as is typically required for an IC engine. 
     Referencing  FIG. 8 , the rapid response energy extracting system  700  may be provided in a non-combustion engine, according to a third embodiment of the present invention. The system  700  includes a chamber  710  with a primary piston  730  and a secondary piston  740 . Instead of internal combustion provided by fuel and oxygen, a fluid  714 , such as a monopropellant or hydrogen peroxide, may enter through an intake port  712  of the chamber  710 . The fluid  714  may pass through or over a reaction member  720 , such as a catalyst or heat-exchanger. Such a catalyst may include silver, silver alloy, and/or a silver/ceramic material. As the fluid  714  passes over the reaction member  720 , a rapid non-combustive reaction results, which may include rapid decomposition of the fluid  714  and/or vaporization of the fluid  714 . As in the IC engine, such rapid non-combustive reaction causes a rapid response from the secondary piston  740  for extracting a portion of energy from the rapid non-combustive reaction. In this system, the primary piston  740  may reciprocate and function similar to the primary piston in the IC engine or, alternatively, the primary piston  730  may simply act as a means for pumping fluid in and out of the chamber  710 . 
     Among many possibilities of use, the above described present invention may be used to provide energetic autonomy to power sources used in robotics. Robots could be powered by self-contained fuel consumption devices which are not tethered to any primary power source. Because the present invention allows for direct conversion of fuel into rapid response energy, any intermediate storage device such as a hydraulic accumulator or electric battery would no longer be necessary, eliminating large weight additions to the robot without sacrificing the speed with which the robot could access power. For example,  FIG. 9  illustrates a wearable exoskeleton frame  800  for use by a human. Such frame  800  may include a central control unit  802 , serving as a fuel storage device, power generation center and/or a signal generation/processing center. The control unit  802  may be interconnected to the rapid response energy extracting system  810  and actuator  806  with an input line  812  from the control unit  802  and output line  814  as shown at  804 . The system can be configured such that the actuator and the rapid response energy extracting system  810  are located at each joint of the exoskeletal frame and are controlled by signals from the master control unit  102 . Alternately, the system could be configured such that one or more rapid response energy extracting systems are located in the central control unit  802  for selectively supplying power to actuators  806  located at each joint of the exoskeleton. 
     In addition to the previous applications, the present invention can be used in any number of applications that require rapid response power without tethering the application to a primary power source. Examples can include power driven wheelchairs, golf carts, automobiles and other vehicles, and generally any applications which leverage mechanical energy and which would benefit by energetic autonomy. 
     While the preceding discussion focused on the characteristics of four stroke internal combustion engines as primary power sources, the present invention is not restricted to use with an internal combustion engine. The present invention can be utilized with any primary power source that delivers variable pulsating pressure. For example, two-stroke internal combustion engines, diesel engines, Stirling engines, external combustion engines and heat engines can all be used as primary power sources for the rapid response power conversion device. 
     It is to be understood that the above-described arrangements are only illustrative of the application of the principles of the present invention. Numerous modifications and alternative arrangements may be devised by those skilled in the art without departing from the spirit and scope of the present invention and the appended claims are intended to cover such modifications and arrangements. Thus, while the present invention has been shown in the drawings and fully described above with particularity and detail in connection with what is presently deemed to be the most practical and preferred embodiment(s) of the invention, it will be apparent to those of ordinary skill in the art that numerous modifications, including, but not limited to, variations in size, materials, shape, form, function and manner of operation, assembly and use may be made, without departing from the principles and concepts of the invention as set forth above.