Abstract:
An aspect of the present invention provides a circuit for generating a voltage that can be used to recharge a battery. The circuit includes an inductive voltage generator operable to generate a magnetic field when the voltage generator is energized by power, and operable to generate a voltage from the magnetic field&#39;s collapse when the voltage generator is de-energized, and a switch operable to allow the voltage generator to receive power to energize the voltage generator, and operable to disconnect the power from the voltage generator to de-energize the generator. With this circuit, a power source that generates less voltage than the fully charged capacity of a rechargeable battery can be used to recharge the battery. Also, the circuit can convert power in different forms, such as constant direct current, varying direct current, or alternating current, into a second voltage for charging a battery. Furthermore, the circuit can supply whatever charging voltage is most suitable for the specific battery that is being charged. Current is delivered to the battery in the form of high energy impulses which can improve the proper removal or deposit of material from/on an electrode of the battery. Consequently the life of the battery being charged by the circuitry employed by the present invention is significantly extended, and, in many cases, a battery that is unable to be charged by traditional means, can be restored to a useable condition.

Description:
BACKGROUND 
       [0001]    Many types of batteries, such as lead-acid, nickel-cadmium, and lithium-ion, can be recharged to replenish their charge and thus be used again to power a device such as an MP3 player, an electric motor for a golf cart, or a starter motor for an internal combustion engine. An advantage to using a rechargeable battery to power a device is that one does not have to purchase many single-use batteries to power the device. 
         [0002]    The process for recharging a battery involves applying a current to the battery that is opposite in polarity to the discharge current generated by the battery. The applied current reverses the battery&#39;s chemical process that occurs in the discharge cycle, and causes material to be deposited on and/or removed from one or more of the battery&#39;s electrodes. Some recharge processes provide the depleted battery a constant current at a voltage that is slightly higher than the standing voltage of the battery when it is fully charged. A problem with this process is that the current does not decrease as the battery nears its full charge capacity. Thus, the battery receives more current than the chemical process can consume when the battery nears it charge capacity. The excess current can damage the battery by:
       1) Converting a portion of its electrolyte into gas which is vented from the battery,   2) Improperly removing material from or depositing material to an electrode of the battery, or   3) Excessively heating the battery.       
 
         [0006]    Another recharge process provides the depleted battery a current at a constant voltage that is slightly higher than the fully recharged capacity of the battery. Thus, as the depleted battery is recharged, the voltage difference between the charging source and the battery decreases, causing the current delivered to the battery to decrease. One problem with this process is that it takes significantly longer for the depleted battery to reach its full charge capacity at the end of the recharge cycle. Another problem is that the battery can suffer the same damaging effects of the constant current recharge process during the beginning of a constant voltage recharge cycle because there is an excessive current caused by an initially high difference in voltage between the charging source and the battery at the beginning of the recharge cycle. 
         [0007]    A problem common to both the constant current and constant voltage charging methods is the inability of the battery to completely reverse all of the battery chemistry to the original condition it had before it was discharged. In other words, with each discharge/recharge cycle there exists a portion of the battery&#39;s chemistry that is not converted back to the charged condition. This results in successive degradation of the battery with each discharge/recharge cycle until the battery&#39;s capacity is lowered beyond a state of practical use and must be replaced. 
       SUMMARY 
       [0008]    An aspect of the present invention provides a circuit for generating a voltage that can be used to recharge a battery. The circuit includes a supply node operable to receive electrical power having a first voltage, a voltage generator operable to generate a magnetic field when the voltage generator is energized by electrical power, and operable to generate a second voltage from the magnetic field&#39;s collapse when the voltage generator is de-energized, an output node operable to provide access to the second voltage, and a switch operable to allow the voltage generator to receive power to energize the voltage generator and operable to disconnect the power from the voltage generator to de-energize the voltage generator. 
         [0009]    With this circuit, a power source that generates less voltage than the fully charged capacity of a rechargeable battery can be used to recharge the battery. As is well known in the art, charging systems employing a solar or wind powered voltage source can only use the power delivered by these sources when the source voltage level is above the voltage level of the battery to be charged. When powered by sources such as solar or wind powered voltage sources under less than optimum conditions, the circuit is able to use power not normally available to charge a battery, i.e. power whose voltage is below that of the battery to be charged. For example, the circuit can operate from a power source providing 0.7 volts to fully recharge a 12 volt battery. Also, the circuit can convert power in different forms, such as constant direct current, direct current that varies over time, or alternating current, into a second voltage for charging a battery. Furthermore, current is delivered to the battery in the form of high energy impulses which can improve the proper removal or deposit of material from/on an electrode of the battery. Consequently the life of the battery being charged by the circuit can be significantly extended, and, in many cases, a battery that is unable to be charged by traditional means can be restored to a useable condition. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0010]      FIG. 1  is a schematic view of a circuit according to an embodiment of the invention. 
           [0011]      FIG. 2  is a schematic view of a circuit according to another embodiment of the invention. 
           [0012]      FIG. 3  is a schematic view of a circuit according to yet another embodiment of the invention. 
           [0013]      FIG. 4  is a schematic view of a circuit according to yet another embodiment of the invention. 
           [0014]      FIG. 5  is a schematic view of a circuit that includes a plurality of circuits similar to the one shown in  FIG. 3 , according to another embodiment of the invention. 
           [0015]      FIG. 6  is a perspective view of one embodiment of the voltage generator of the circuit shown in  FIG. 3  and the circuit shown in  FIG. 4 , according to an embodiment of the invention. 
           [0016]      FIG. 7  is a perspective view of one embodiment of the voltage generator of the circuit shown in  FIG. 3  and the circuit shown in  FIG. 4 , according to another embodiment of the invention. 
           [0017]      FIG. 8  is a perspective view of one embodiment of the voltage generator of the circuit shown in  FIG. 3  and the circuit shown in  FIG. 4 , according to yet another embodiment of the invention. 
           [0018]      FIG. 9  is a perspective view of one embodiment of the voltage generator of the circuit shown in  FIG. 3  and the circuit shown in  FIG. 4 , according to yet another embodiment of the invention. 
           [0019]      FIG. 10  is a schematic view of a system that includes a charging circuit according to an embodiment of the invention. 
           [0020]      FIG. 11  is a schematic view of a system that includes a charging circuit according to another embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]      FIG. 1  is a schematic view of a circuit  20  according to an embodiment of the invention. The circuit  20  can be used to recharge a battery  22 , and can also be used to repair and/or rejuvenate a battery by improving the proper removal or deposit of material from/on an electrode of the battery. The circuit  20  includes a supply node  24  that can be coupled to a source  26  of power having a voltage. The circuit  20  also includes a voltage generator  28  that generates a magnetic field when the power from the source  26  energizes the generator  28 , and that generates a voltage from the magnetic field&#39;s collapse when the generator  28  is de-energized. The circuit  20  also includes an output node  30  that provides access to the voltage generated by the voltage generator  28 , and a switch  32  to allow one to control the flow of power from the source  26  to the generator  28  to energize or de-energize the generator  28 . 
         [0022]    In operation, the circuit  20  generates a voltage spike—a high voltage condition lasting for a short period of time—from the collapse of a magnetic field that is generated by the voltage generator  28 . Because the magnetic field collapses quickly, the voltage spike forms quickly, and the voltage in the spike is high. When the magnetic field is generated and then collapses, repeatedly, the circuit  20  generates a series of voltage spikes. Each voltage spike is directed to the output node  30  where it is available for use by the battery  22  or some other device. When the circuit  20  generates a series of voltage spikes, the voltage available at the output node  30  pulsates. Thus, the circuit  20  can apply sharp, high-voltage spikes to recharge the battery  22 . 
         [0023]    The voltage generator  28  generates the magnetic field from current flowing through the generator  28 . When the voltage generator  28  is coupled to the power source  26  and the switch  32  is closed, the voltage of the source&#39;s power causes current to flow through the generator  28  and toward ground  34 , thus energizing the generator  28 . To collapse the magnetic field generated by the generator  28 , one opens the switch  32  to stop the flow of current through the generator  28 , thus de-energizing the generator  28 . 
         [0024]    Because the voltage spikes are brief moments of high voltage, the spikes can be used to provide a battery  22  pulses of substantial current to recharge the battery  22  without generating excessive heat in the batteries anode and cathode plates. Current delivered to the battery in the form of these high energy impulses can improve the proper removal or deposit of material from/on an electrode of the battery. In addition, because the voltage of the voltage spikes is typically greater than the voltage of the power source  26 , the circuit  20  can be used to recharge a battery  22  having a remaining voltage or a fully charged voltage that is greater than the voltage of the power provided by the source  26 . 
         [0025]    Still referring to  FIG. 1  the power source  26  can be any desired power source capable of providing enough power to energize the voltage generator  28 . For example, in this and certain other embodiments the power source  26  provides a substantially constant 10 volts. Thus, when switch  32  is closed, direct current flows through the voltage generator  28 . In other embodiments, the power source  26  can provide a voltage and current that varies over time. An example of such a power source includes a solar cell array that generates a voltage and current during the night or cloudy days that is less than the voltage and current it generates on a sunny day. Another example of a varying voltage source includes a windmill whose available power varies with wind speed. The advantage of the present invention when using such solar or wind powered voltage sources is that the circuit is able to charge a battery whose voltage is significantly higher than the voltage delivered by the power source. In still other embodiments, the power source  26  can provide a voltage that follows a saw tooth or sinusoidal pattern over time. If the power source  26  provides AC power, the power should be rectified and filtered before powering the voltage generator  28 . Because the pulse of voltage spikes at the output node  30  depends on the opening and closing sequence of the switch  32 , the circuit  20  can also modify the form of the power from the power source  26 . 
         [0026]    Still referring to  FIG. 1 , the voltage generator  28  includes a component that generates a magnetic field when energized. For example, in some embodiments of the voltage generator, the component is a conductor  36  coiled around an axis (not shown) similar to a conventional inductor, and has an inductance of 200 μH. The strength of the magnetic field generated by the conductor  36  when energized, and thus the voltage generated as the field collapses, depends on the amount of current flowing through the generator  28 , the size of each coil in the conductor, and the number of coils in the conductor. The specific size of each coil in the conductor and the specific number of coils in the conductor can be any desired size and number that provides a desired field strength. 
         [0027]    Other embodiments of the component of the voltage generator  28  are possible. For example, as discussed in greater detail in conjunction with  FIG. 7 , the component may be a conductor that is substantially straight; not coiled around an axis. As another example, the component may include a conductor in the vicinity of an iron, ferrite, or other magnetically affected material to alter the inductance of the voltage generator. 
         [0028]    Still referring to  FIG. 1 , the switch  32  can be any switch capable of opening and closing the circuit to allow one to control the flow of current through the generator  28 . For example, in this and certain other embodiments, the switch is a conventional mechanically operated switch. When switch  32  is closed, current flows through the voltage generator  28  to energize the generator  28 . When switch  32  is opened, power stops flowing through the voltage regulator  28  to de-energize the generator  28 . 
         [0029]    Other embodiments of the switch  32  are possible. For example, the switch may be electrically operated as discussed in greater detail in conjunction with  FIGS. 2-5 . 
         [0030]    Still referring to  FIG. 1 , the circuit  20  also includes a component for isolating the voltage generated by the voltage generator  28 . For example, in this and certain other embodiments the component includes a diode or other rectifying device  38  that allows current to flow from the generator  28  to the output node  30  but not in the opposite direction. Thus, the voltage generated by the battery  22  can remain isolated from the voltage generator  28  while the generator  28  is energized. 
         [0031]      FIG. 2  is a schematic view of a circuit  40  according to another embodiment of the invention. The circuit  40  is similar to the circuit  20  but includes a switch  42  that is electrically operated; not mechanically operated. The switch  42  includes a transistor  44  to control the flow of current through the voltage generator  28 , and a trigger  46  to control the operation of the transistor  44 . 
         [0032]    The transistor  44  includes a base  46 , a collector  48 , and an emitter  50 . When the base  46  receives a voltage that is greater than a threshold voltage, current can flow into the collector  48  through the transistor  44  to the emitter  50 , and thus the transistor is closed. When the voltage at the base  46  is less than the threshold voltage, current does not flow into the collector  48  through the transistor  44  and out the emitter  50 , and thus the transistor is open. 
         [0033]    The transistor  44  can be any desired transistor that allows one to control the flow of current through the voltage generator  28 . For example, in this and certain other embodiments, the transistor  44  is an NPN bipolar transistor having a threshold voltage of about 0.7 volts. In other embodiments, the transistor  44  may be a PNP bipolar transistor. In still other embodiments, the transistor  44  may be any desired field-effect transistor such as a MOSFET, JFET, or IGBT that has a source that is functionally equivalent to the emitter  50 , a drain that is functionally equivalent to the collector  48 , and a gate that is functionally equivalent to the base  46 . In still other embodiments, the transistor  44  may be any other desired semiconductor switching device. 
         [0034]    The trigger  46  includes a DC pulse generating circuit  52  that provides a voltage to the base  46  of the transistor  44  that is greater than the threshold voltage. Thus, when the DC pulse generator  52  provides a voltage to the base  46 , the transistor  44  allows current from the power source  26  to flow through the generator  28 , thus energizing the generator  28 . When the DC pulse generator  52  does not provide a voltage to the base  46 , the transistor  44  prevents current from the power source  26  from flowing through the generator  28 , thus de-energizing the generator  28 . 
         [0035]    Still referring to  FIG. 2 , the switch  42  also includes diodes  54  and  56  to protect the base  46  and isolate the voltage generated by the generator  28  when the magnetic filed collapses. Diodes  54  and  56  are not necessary to the switch  42 , but protect the transistor  44  by routing any negative high voltage transients to ground  34 . 
         [0036]      FIG. 3  is a schematic view of a circuit  60  according to yet another embodiment of the invention. The circuit  60  is similar to the circuit  40  ( FIG. 2 ) but includes a switch  62  that automatically closes to energize the voltage generator  28  and automatically opens to de-energize the generator  28 —i.e. the circuit  60  oscillates by itself when coupled to the power source  26 . With a switch  62  that automatically opens and closes, the circuit  60  can self oscillate when powered from a source whose voltage and current vary. An example of such a power source includes a solar cell array that generates a voltage and current during the night or cloudy days that is less than the voltage and current it generates on a sunny day. Another example of a varying voltage source includes a windmill whose available power varies with wind speed. When using solar or wind powered voltage sources, the circuit  60  is able to recharge a battery whose voltage is significantly higher than the voltage delivered by the power source. 
         [0037]    The switch  62  includes a transistor  44  (bipolar transistor, MOSFET, JFET, IGBT, or any other desired semiconductor switching device) to control the flow of current through the voltage generator  28 , and a trigger  64  to control the operation of the transistor  44 . The trigger  64  generates a voltage opposite to the voltage applied to the transistor&#39;s base  46  from the power source  26  ( FIG. 1 ), and opens the transistor  44  when the generated voltage reduces the voltage applied to the base  46  below the transistor&#39;s threshold voltage. The power source  26  powers the voltage generator  28 , the trigger  64 , and the transistor  44 , and thus the circuit  60  self-oscillates to energize and de-energize the voltage regulator  28 . 
         [0038]    Still referring to  FIG. 3 , in this and certain other embodiments of the trigger  64 , the trigger  64  includes a component that generates a voltage from the magnetic field generated by the voltage generator  28 . For example, in this and certain other embodiments of the trigger  64 , the trigger  64  includes a conductor  66  coiled around an axis (not shown) similar to a conventional inductor, and has an inductance of 200 μh. The coiled conductor  66  can have any desired coil size and any desired number of coils to provide any desired inductance and thus any desired voltage induced by the magnetic field generated by the voltage generator  28 . 
         [0039]    The coiled conductor  66  is oriented relative to the voltage generator  28  such that current flowing from the power source  26  flows through the coiled conductor in a direction opposite than the direction that current flowing from the power source  28  flows through the generator  28 . When power from the source is initially applied to the supply node  24 , power flows through the coiled conductor  66  and a voltage is applied at the base of the transistor  44 . The switch  62  closes, and power begins to flow through the voltage generator  28 . The magnetic field generated by the generator  28  induces a voltage in the coiled conductor  66  that opposes the voltage from the power source  26 . When the induced voltage is sufficient to reduce the voltage at the base  46  below the threshold voltage, the transistor  44  opens causing the generator  28  to de-energize. This then causes the magnetic field around the generator  28  to collapse, and thus generate a voltage spike. Because the magnetic field collapses quickly, the voltage spike forms quickly, and the voltage in the spike is high. As the generator&#39;s magnetic field collapses, it induces a positive voltage in the coiled conductor  66  that increases and combines with the voltage from the power source  26 . When the combined voltage is above the transistor&#39;s threshold voltage the transistor  44  closes causing the generator  28  to re-energize. In this manner the circuit  60  can use the power from the power source  26  to generate a series of voltage spikes by self-oscillating the voltage applied to the base  46  of transistor  44 , and thus the current that flows through the generator  28 . 
         [0040]    The oscillation of voltage applied to the base  46  can have any desired period. For example, in this and certain other embodiments the period is 15,000 cycles per second. In other embodiments, the period can be 60 cycles per second. Because the collapse of the generator&#39;s magnetic field generates the voltage spike, the amount of voltage in the spike depends on the strength of the magnetic field. Before the magnetic field is fully developed, the strength of the magnetic field depends on the length of time that the current flows through the generator  28 . An oscillation period that is long, i.e. the number of cycles per second is few, increases the length of time that current flows through the generator  28  when the switch  62  is closed. Thus the generated magnetic field is strong, and the spike&#39;s voltage is high. An oscillation period that is short, i.e. the number of cycles per second is many, decreases the length of time that current flows through the generator  28  when the switch  62  is closed. Thus the generated magnetic field is weaker, and the spike&#39;s voltage is less. 
         [0041]    Still referring to  FIG. 3 , the switch  60  can include a resistor  68  having any desired resistance. For example, in this and certain other embodiments, the resistor&#39;s resistance is 470 Ohms. The resistance of resistor  68  affects the oscillation period of the voltage applied to the base  46  of the transistor  44 . A resistor  68  having a high resistance causes current to flow through the generator  28  for a shorter period than a resistor  68  having a lower resistance. 
         [0042]      FIG. 4  is a schematic view of a circuit  70  according to yet another embodiment of the invention. The circuit  70  is similar to the circuit  60  ( FIG. 3 ) but includes a switch  72  that has a resistor  74  that replaces the diode  54  ( FIG. 2 ), and resistor  76  to bias the voltage applied to the base  46  of the transistor. 
         [0043]    The combination of the resistors  74 ,  76  and  78 , affects the oscillation period of the voltage applied to the base  46  of the transistor  44 . Raising the value of resistor  74  causes current to flow through the generator  28  for a shorter period. Raising the value of resistors  76  and/or  78  causes current to flow through the generator  28  for a longer period. 
         [0044]      FIG. 5  is a schematic view of a circuit  80  that includes a plurality of circuits  82 , each similar to the circuit  60  ( FIG. 3 ), according to another embodiment of the invention. Each circuit  82  includes a voltage generator  28 , and a transistor  44 . The circuit  80  includes a trigger  84  that is used to oscillate the flow of power through each circuit  82 . The circuits  82  are arranged so that the power that each voltage generator  28  generates from the collapse of their respective magnetic fields is combined with the power from the others to make a significant amount of power available at the output node  86 . The circuit  80  can have any desired number of circuits  82  to provide a desired amount of power at the output node  86 . 
         [0045]      FIG. 6  is a perspective view of a voltage generator&#39;s coiled conductor  90  and a trigger&#39;s coiled conductor  92  of the circuit  60  shown in  FIG. 3  and the circuit  70  shown in  FIG. 4 , according to an embodiment of the invention. In this embodiment, both coiled conductors  90  and  92  are components of a coaxial cable that has been coiled. In other embodiments, the coiled conductor  90  can be the trigger&#39;s coiled conductor, and the coiled conductor  92  can be the voltage generator&#39;s coiled conductor. 
         [0046]      FIG. 7  is a perspective view of a voltage generator&#39;s conductor  100  and a trigger&#39;s conductor  102  of the circuit  60  shown in  FIG. 3  and the circuit  70  shown in  FIG. 4 , according to another embodiment of the invention. In this embodiment, the voltage generator&#39;s conductor  100  and trigger&#39;s conductor  102  are shown to be coaxial and straight, not coiled. In other embodiments, the conductor  100  can be the trigger&#39;s conductor, and the conductor  102  can be the voltage generator&#39;s conductor. 
         [0047]    Other embodiments are possible. For example either or both conductors  100  and  102  can have any shape desired to fit any desired application requirements. For example the conductors  100  and  102  can spiral in a single plane as shown in  FIG. 9  as would be the case if etched on a common circuit board, or they can serpentine. 
         [0048]      FIG. 8  is a perspective view of a voltage generator&#39;s conductor  110  and a trigger&#39;s conductor  112  of the circuit  60  shown in  FIG. 3  and the circuit  70  shown in  FIG. 4 , according to another embodiment of the invention. The conductor  110  includes six separate wires  110   a ,  110   b ,  110   c ,  110   d ,  110   e ,  110   f  that each generate a portion of the magnetic field generated by the generator  28  ( FIG. 5 ) when current flows through the conductor  110 , and generate a portion of the voltage generated by the generator from the collapse of their respective portions of the magnetic field. The conductor  112  generates a voltage opposite to the voltage applied to the transistor&#39;s base  46  (shown in  FIG. 5 , but omitted from  FIG. 8  for clarity), and opens the transistor  44  (shown in  FIG. 5 , but omitted from  FIG. 8  for clarity) when the generated voltage reduces the voltage applied to the base  46  below the transistor&#39;s threshold voltage. 
         [0049]      FIG. 9  is a perspective view of a voltage generator&#39;s conductor  120  and a trigger&#39;s conductor  122  of the circuit  60  shown in  FIG. 3  and the circuit  70  shown in  FIG. 4 , according to another embodiment of the invention. The conductor  120  includes two separate traces  120   a  and  120   b  disposed in/on a circuit board that each generate a portion of the magnetic field generated by the generator  28  ( FIG. 5 ) when current flows through the conductor  120 , and generate a portion of the voltage generated by the generator from the collapse of their respective portions of the magnetic field. The conductor  122  generates a voltage opposite the voltage applied to the transistor&#39;s base  46  (shown in  FIG. 5 , but omitted from  FIG. 9  for clarity), and opens the transistor  44  (shown in  FIG. 5 , but omitted from  FIG. 9  for clarity) when the generated voltage reduces the voltage applied to the base  46  below the transistor&#39;s threshold voltage. 
         [0050]      FIG. 10  is a schematic view of a system  130  that includes a charging circuit  132 , according to an embodiment of the invention. The charging circuit  132  can be the circuit  20  ( FIG. 1 ), the circuit  40  ( FIG. 2 ), the circuit  60  ( FIG. 3 ) and/or the circuit  70  ( FIG. 4 ). The system  130  also includes a circuit controller  134  that controls the connection of the power source  26  to the supply node  24  ( FIG. 1 ). The circuit controller  134  can also, if desired, control the connection of the battery  22  to a load  136 , such as an electric motor, (if present). 
         [0051]    In this and certain other embodiments, the circuit controller  134  includes a processor or microcontroller (not shown) that executes instructions expressed in software, and one or more circuits (also not shown) to monitor operating conditions of the load  136 , the battery  22 , and/or the charging circuit  132 . In this and certain other embodiments, the controller  134  includes a circuit to confirm the presence of the battery  22  before connecting the charging circuit  132  to charge the battery  22 . The controller  134  may also include other circuits to detect the voltage and/or temperature of the battery  22  to monitor the voltage and/or temperature and stop the charging process when the battery  22  is fully charged. 
         [0052]      FIG. 11  is a schematic view of a system  140  that includes a charging circuit  132 , according to another embodiment of the invention. The system  140  is similar to the system  130  except the system  140  includes two batteries  142  and  144 . In this and certain other embodiments, each battery  142  and  144  can deliver the amount of power that the load  136  requires, and thus alternately power the load  136 . A benefit of this arrangement is that while one of the batteries  142  and  144  powers the load  136 , the other battery  144  or  142  can be recharged by the charging circuit  132 . Thus, in this and certain other embodiments, the circuit controller  134  can also include a switch (not shown) that connects one of the batteries  142  or  144  to the charging circuit  132  to recharge the battery while the other battery powers the load  136 . And, when the powering battery is depleted or the charging battery is fully charged, the switch can connect the recharged battery to the load  136  to power the load, and connect the depleted battery to the charging circuit  132  to recharge the battery. 
         [0053]    The preceding discussion is presented to enable a person skilled in the art to make and use the invention. The general principles described herein may be applied to embodiments and applications other than those detailed above without departing from the spirit and scope of the present invention. The present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed or suggested herein.