Patent Document

RELATED APPLICATION 
     Applicant claims the benefit of a provisional patent application filed on Nov. 5, 1999, with Ser. No. 60/163,771. 
    
    
     Attorneys for Inventor: Malcolm E. Whittaker, Registered Patent Attorney No. 37,965, Mineo &amp; Whittaker, P.O. Box 10615, Charlotte, N.C. 28212 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a typical race car. 
     FIG. 2 is a block diagram of present day fuel cell, engine block and fuel pump and related parts. 
     FIG. 3 is a perspective view of a typical engine fuel pump with the microswitch attached. 
     FIG. 4 is a perspective view of the fuel pump assembly of the present invention. 
     FIG. 5 is a top view of the fuel pump assembly and related microswitch assembly. 
     FIG. 6 is a bottom view of the fuel pump assembly and related microswitch assembly. 
     FIG. 7 is a back view of the fuel pump and related microswitch of the present invention. 
     FIG. 8 is a front view of the fuel pump and related microswitch of the present invention. 
     FIG. 9 is a right side view of the fuel pump and related microswitch of the present invention. 
     FIG. 10 is a left side view of the fuel pump and related microswitch of the present invention. 
     FIG. 11 is a perspective view of the fuel flow cut off assembly. 
     FIG. 12 is a perspective view of the fuel pump assembly showing the nut and bolt which fasten the fuel pump assembly to the microswitch assembly. 
     FIG. 13 is a perspective view of the bracket which fastens the fuel pump assembly to the engine block of a typical race car. 
     FIG. 14 is an exploded view of the fuel cut off assembly. 
     FIG. 15 is a perspective view of the control box assembly of the present invention. 
     FIG. 16 is a perspective view of the control box assembly of the present invention with the wiring shown. 
     FIG. 17 is a top view of the wiring harness of the present invention. 
     FIG. 18 is a perspective view of an alternative embodiment of the control box of the present invention. 
    
    
     DESCRIPTION OF THE INVENTION 
     In recent years, the National Association for Stock Car Automobile Racing (“NASCAR”) has increased in popularity. Because of the increased popularity of NASCAR, ever increasing numbers of races are being added to the NASCAR racing schedule and increasing numbers of Stock Cars are competing in NASCAR races. In the past few years, there have been a substantial number of “underhood” fires in cars competing in NASCAR races. In most cases, these underhood fires have been caused by race cars crashing into guard rails, pit walls or outside retaining walls which surround the race track. In many cases, the crash will break the race car&#39;s fuel pump off the engine block or the fuel line being broken off the fuel pump. One of the main causes of the fuel pump and fuel line breakage is the close proximity of the fuel pump and fuel line to the race car&#39;s main front cross member. NASCAR rules and regulations mandate the position of the fuel pump and fuel lines in the race car. 
     As stated by the name, a “fuel pump” pumps fuel from the fuel cell to the race car&#39;s engine. Typically, the words “fuel cell” and “gas tank” are interchangeable. 
     As is well known in NASCAR, NASCAR rules and regulations mandate the position of both the fuel cell and fuel pump in each race car. It is a well known problem that an automobile crash, particularly at the high speeds found in automobile racing, produces sparks. If and when the fuel pump or fuel line are broken off or ruptured, the sparks from the crash are likely to ignite the gasoline which has escaped. This burning gasoline is the cause of the “underhood fires” discussed above. An additional heat source is the engine headers which are approximately 1300 degrees Fahrenheit and can cause spontaneous combustion of gasoline vapor fumes. 
     The present invention will automatically cut of the flow of fuel from the fuel cell if either the fuel line is detached from the fuel pump or the fuel pump is broken off the engine block. 
     At the present time, when the fuel pump is activated by the engine, it urges fuel from the fuel cell toward the engine block where the fuel is combusted in the engine to propel the race car. The present invention includes a fuel cut off assembly which if the micro-switch assembly mounted on the fuel pump assembly is opened, the flow of current to the solenoid valve is cut off and the solenoid valve instantaneously closes. When the solenoid valve closes, the flow of fuel through the fuel line is instantaneously cut off. 
     As is well known, a fire requires fuel, flame and oxygen. Oxygen is found in the atmosphere. The flame is created by the sparks which are caused by virtually any collision which a race car may be involved in. The present invention prevents an underhood fire by cutting off the flow of fuel, typically gasoline, to the engine and to the area of the race car under the race car&#39;s hood. 
     The present invention has four main components. First, a fuel pump assembly  70 . Second a related microswitch assembly  90 . Third, a fuel flow shut off assembly  80 . Fourth, a control box assembly  100 . 
     As seen in FIG. 1, a typical race car  110 , has a number of common components. FIG. 2 shows these common components; a fuel cell  20 , a fuel line  30 , a rear fire wall  40 , a front fire wall  50 , an engine  60 . Associated with the engine block is a fuel pump assembly  70 . Typically, the fuel pump assembly  70  is mounted on engine  60 . 
     As seen in FIG. 2, when the fuel pump assembly  70  is activated, it urges fuel from the fuel cell  20  toward the engine  60  where the fuel is combusted in the engine  60  to propel race car  110 . 
     FIG. 3 is a perspective view of an embodiment of the fuel pump assembly  70 . Fuel pump assembly is one of the components of the present invention. As discussed above, in the fuel pump assemblies found in present race cars, if the fuel pump assembly is separated from engine  60 , the present day fuel pump assembly continues to syphon fuel from fuel cell  20 . This is the cause of a substantial number of underhood fires after racing accidents. It can be seen that, in the present invention, fuel enters and exits fuel pump assembly  70  through fuel inlet  31  and fuel outlet  32 . 
     FIGS. 3 and 4 show the fuel pump assembly  70  and microswitch assembly  90  portion of the present invention. Specifically, FIGS. 3 and 4, show the microswitch assembly  90  in the “closed” position in FIG.  4 . The microswitch assembly  90  is shown in the “open” position in FIG.  3 . During normal operation of a race car  110 , it is expected that the microswitch assembly  90  will be in the “closed” position seen in FIG.  4 . When the microswitch assembly  90  is in the “closed” position, the electrical connector  99 , which has an inlet for electric current and an outlet for electric current, the inlet for electric current is attached to a power source. In the preferred embodiment, this is a 12 Volt DC power source. Typically, this is a 12 Volt DC car battery. 
     The fuel pump assembly  70  is removably attached to the engine  60  by bracket  72 . In the preferred embodiment, bracket  72  is made of mild steel and is plated with Nickel Teflon. In the preferred embodiment, bracket  72  is {fraction (105/1000)}&#39;s of an inch thick. In the preferred embodiment, fuel pump assembly  70  is removably fastened to bracket  72  by two ⅜×16×2″12 point grade 8 bolts. Preferably, ⅜ washers will be also be used to fasten fuel pump assembly  70  and bracket  72  to engine block  60 . Of course, fuel pump assembly  70  does not have to be attached directly to engine  60 . It could be located close to the engine such that fuel pump assembly  70  can communicate fuel to engine  60 . In addition, bracket  72  and notch  73  may be thought of as limit switch locator because plunger  94 , which may be described as part of a limit switch, are coupled and because de-coupled when plunger  94  and notch  73  are not in contact. In other words, bracket  72  and notch  73  may be described as a limit switch locator. Plunger  94  may be described as part of a limit switch. 
     FIG. 3 shows microswitch assembly  90 . Microswitch  90  includes case  92 , plunger  94  and electrical connector  99 . When microswitch  90  is in the “closed” position seen in FIG. 4, the circuit is complete and current flows into and out of electrical connector  99 . As discussed above, a voltage sources drives current into electrical connector  99  and out of electrical connector  99  when plunger  94  is depressed and in contact with notch  73 , as seen in FIG.  4 . In other words, the circuit is closed and electric current flows into the inlet port of electrical connector  99 , thorough microswitch  90  and through the outlet port of electrical connector  99 . When plunger  94  is not in contact with notch  73 , plunger  94  is not depressed and the electric circuit running into the inlet port of electrical connector  99 , through microswitch assembly  90 , cannot exit the outlet port of electrical connector  99 . In other words, the circuit is “broken” or “opened.” This is important because if the circuit is broken, power will not reach any device which is connected to the outlet port of electrical connector  99  and fuel flow will stop. As discussed above, microswitch  90  may as be described as an impact sensitive limit switch. 
     In the preferred embodiment, microswitch assembly  90  is built by the Square D company. It is heavy duty and completely encapsulated, zinc die-cast, epoxy filled and roller plunger  94  is mounted on top of microswitch assembly  90  as seen in FIGS. 3 and 4. In the preferred embodiment, plunger  94  is made of high grade steel to resist corrosion and has a roller wheel at the end of plunger  94  which makes contact with notch  73 . In the preferred embodiment, the microswitch assembly  90  includes a switch of NEMA type 1, 2, 4, 6, 6P, 12, 13, IP67. The switch has gold contacts and is dust, water, oil, gasoline and vibration resistant. Preferably, the switch will withstand vibration of 10G&#39;s and a shock load of 35G&#39;s. Preferably, the gold contacts should be rated at 5 amps at 24 Volts DC. In the preferred embodiment, electrical connector  99  will include a wiring harness consisting of 12 inches of an 18 gauge 2 conductor wire with a jacket insulation with the trade name “PUR.” Electrical connector  99  is also preferably water, oil and gasoline resistant. Electrical connector  99 &#39;s wire should be rated to 105 degrees Centigrade. 
     As seen in FIGS. 3 and 4, one end of electrical connector  99  will terminate in microswitch assembly  90 . The other end, is preferably a two pin male connector located in an ABS plastic housing. At the present time, the ABS housing is made by Packard Electrical Systems and is dust and water resistant. 
     As discussed above, when a race car  110  is involved in an accident, the fuel pump assembly  70  is frequently broken open or torn off engine  60 . At the present time, when this happens, fuel cell  20  and fuel line  30  continue to communicate fuel into the engine compartment of race car  110 . This is the fuel which feeds the fire started by sparks generated in the accident which tore off or damaged fuel pump assembly  70 . 
     As seen from the name “impact sensitive fuel control system,” the goal of the present invention is to prevent fuel reaching the engine compartment of race car  110  if fuel pump assembly is damaged or torn off engine  60 . 
     If fuel pump assembly  70  is damaged or torn off engine  60 , plunger  94  of microswitch assembly  90  will be urged by the force of the collision to disconnect from notch  73 , as seen in FIG. 3, to the position of non-contact between plunger  94  and notch  73  seen in FIG.  4 . In other words, plunger  94  will no longer touch notch  73 . As discussed above, the electric circuit formed by electrical connector  99  and microswitch  90  will be broken if plunger  94  does not contact notch  73 . This is important because electrical connect  99  communicates with fuel cut off assembly  80 , as seen in FIGS. 2-10 and  14 . 
     As seen in FIG. 2, if fuel pump assembly  70  is not energized(by current flowing from electrical connector  99 ), it will prevent the passage of fuel through fuel line  30 . In the preferred embodiment, fuel cut off assembly  80  is located such that it interrupts the flow of fuel before the fuel enters the fuel line forward of the front fire wall  50  of race car  110 . 
     Turning now to FIGS. 2,  4 ,  11  and  14 , fuel cut off assembly  80  comprises solenoid  81 , holder  82 , valve body  83 , free spring  84 , diaphragm  85 , slider  85 A, attached spring  85 B, washer  86 , base  87 , orifice  87 A and fasteners  88 . In typical operation, plunger  94  will be in contact with notch  73  and current will flow through electrical connector  99  to solenoid  81 . If fuel pump assembly  70  is damaged or torn off engine  60 , plunger  94  will be urged out of contact with notch  73 . Therefore, electrical connector  99  will instantly stop delivering current to solenoid  81 . As best seen in FIG. 14, when microswitch  90  is in the “closed” position (seen in FIG. 4) solenoid  81  is energized and slider  85 A is urged towards solenoid  81 . When slider  85 A is urged towards solenoid  81 , slider  85 A compresses free spring  84  and tensions attached spring  85 B. Attached spring  85 B in turn urges diaphragm  85  towards solenoid  81 . When diaphragm  85  moves towards solenoid  81 , fuel can flow through fuel line  30  and then through base  87  and orifice  87 A. 
     If plunger  94  is not in contact with notch  73 , current will not flow through electrical connector  99  to solenoid  81 . If solenoid  81  is not energized, slider  85 A will be urged towards base  87  by free spring  84 . The movement of slider  85 A will in turn compress attached spring  85 B and re-seat diaphragm  85  against the base  87 . This will prevent the flow of fuel through orifice  87 A. Because fuel cannot flow, the supply of fuel to the engine or to a fire which is burning forward of the front fire wall  50  will be cut off. In other words, if the fuel pump assembly  70  is torn off or damaged, there will be no underhood fire because the flow of fuel will be instantaneously interrupted by the closing of diaphragm  85  down onto orifice  87 A in valve body  87 . 
     As seen in FIGS. 11 and 14, fuel cut off assembly  80  is removably fastened to race car  110  by holder  82 . Also, valve body  83  slidably receives slider  85 A. In addition, entire fuel cut off assembly  80  is held together by fasteners  88 . Holder  82  is preferably made of mild steel and is also preferably plated with Nickel Teflon. In its preferred embodiment, holder  82  is {fraction (105/1000)}&#39;s of an inch thick and is mounted to front fire wall  50  by means of fasteners that include self locking nuts. 
     In the preferred embodiment, fuel cut off assembly  80  will operate at pressures ranging from 0 to 25 lbs. of force. In addition, in order to minimize the danger of fuel starvation caused by the present invention, orifice  87 A preferably has a diameter that is 50% bigger than the diameters of fuel outlet  200 A or fuel outlet  200 , seen in FIG.  14 . In addition, the fuel cut off assembly preferably has a pilot and bleed orifice to help seat the diaphragm. Preferably, the diaphragm is made of viton elastomer. In addition, solenoid  81  preferably are Red Hat  2  solenoid enclosures which are molded one piece construction with a built in ½″ N.P.T. conduit. Preferably, solenoid  81  will operate at temperatures up to and including about 200 degrees Centigrade (425 degrees F.) and have a useful life of about 10,000 hours when connected to power dissipating resistors  106 A and  106 B. Preferably, solenoid  81  has a NEMA (National Electrical Manufacturers Association) classification of 1, 2, 3, 3s, 3r, 4 and 4x. Valve body  83  and base  87  are preferably T-6061 machined aluminum. In addition, the use of free spring  84  and attached spring  85 B eliminates the danger that when solenoid  81  is energized that diaphragm  85  will not permit the flow of fuel. It is also preferable that fasteners  88  be tightened to 105 ft-lbs and make use of a grade 8 washer. In addition, it is also preferable to make use of safety wire to more securely fasten fasteners  88 . It is also preferable to use safety wire in conjunction with the nuts and bolts which hold fuel pump assembly  70  together. Of course, fuel cut off assembly  80  could be replaced with any equivalent, such as a plunger or a ball valve or another valve that can be opened or closed. 
     As discussed above, electrical connection  99  communicates with fuel cut off assembly  80 . As discussed above, the final assembly of the present invention is control box assembly  100 . First control box assembly  100  is seen in FIGS. 15 and 16. First Control box assembly  100  is in turn connected to fuel cut off assembly  80  as seen in FIG. 17. A more specific wiring diagram of FIG. 15 is shown in FIG.  16 . 
     As seen in FIGS. 15,  16 , and  17 , the control box assembly  100  is an ON/ON switch. This means that the solenoid will not be de-energized, and fuel cut off to the engine unless plunger  94  is not in contact with notch  73 , as discussed above. In other words, if the control box assembly is set to “AUTO,” this means that if race car  110  is subject to a collision which separates plunger  94  from notch  73 , solenoid  81  will instantly drop power and the flow of fuel through fuel line  30  will instantly be interrupted. 
     However, if any collision does not sufficiently damage race car  110  to prevent race car  110  from continuing the race, control box assembly  100  can be set to “MANUAL.” When control box assembly  100  is set to “MANUAL,” microswitch assembly  90  is bypassed and solenoid  81  is energized. As explained above, when solenoid  81  is energized, fuel can reach the engine  60 . Therefore, control box assembly  100  is useful if race car  110  has suffered a small accident, which has urged plunger  94  out of contact with notch  73 , but is not sufficiently damaged to require race car  110  to leave the race. Of course, after suffering an accident, race car  110  would be “pitted” and plunger  94  could be pushed into contact with notch  73 . If plunger  94  and notch  73  cannot physically be brought into contact, the “MANUAL” position on control box assembly  100  will energize solenoid  81  and allow fuel to flow. If for some reason the driver of race car  110  believes that there is an underhood fire, he or she can move the switch of control box assembly  100  to the “AUTO” position and solenoid  81  will be de-energized and the flow of fuel interrupted because plunger  94  is not in contact with notch  73  and the circuit is “broken.” Because the circuit is “broken,” solenoid  81  will be de-energized and the flow of fuel interrupted. 
     FIGS. 15 and 16 illustrate first control box assembly  100 . First control box assembly comprises cover  101 , base  102 , AUTO light indicator  103 , MANUAL light indicator  104 , ON/ON switch  105 , two power dissipating resistors  106 A and  106 B, circuit breaker  107 , diodes  108 A and  108 B and resistor  109 . Resistor  109  is a 3 ohm resistor which ensures that solenoid  81  does not receive greater than 12 volts at any given time. Because of the size of first control box assembly  100 , it is expected that it will be mounted on the front side of the dash board of race car  110  within reach of the driver. Specifically, cover  101  is preferably made with ABS plastic with a flammability rating of 94V−0 at 0.080″ thickness and a continuous use temperature of 70 degrees Centigrade. Typically, cover  101  will have a textured finish and dimensions of 4 ½″×3″×2″. Base  102  will typically be made from aluminum and be about 0.125″ thick. Base  102  also serves as a backing plate and heat sink for power dissipation resistors  106 A and  106 B. Circuit breaker  107  is preferably a 3 ampere aircraft type circuit breaker. 
     FIG. 15 shows AUTO indicator light  103  and MANUAL indicator light  104  protruding through cover  101 . Power dissipating resistor  106 A and diode  108 A are associated with AUTO indicator light  103 . Similarly, power dissipating resistor  106 B and diode  108 B are associated with MANUAL indicator light  104 . The power dissipating resistors and diodes are necessary to prevent a foreshortened life for solenoid  81 . Specifically, the output voltage of a typical race car  110 &#39;s electrical system is 14.6 DC volts. Because solenoid  81  requires only 12 DC volts to operate, its life would be cut by about 75%. The power dissipating resistors are wrapped with wire, as seen in FIGS. 15 and 16. Combined with the base plate  102 &#39;s function as an aluminum, or other highly conductive metal, heat sink allows solenoid  81  to “see” no more than 12.07 DC volts. Preferably, the wire wrapped around power dissipating resistors  106 A and  106 B should be epoxy encapsulated in position. In addition, diodes  108 A and  108 B ensure that there is no current “back flow” through power dissipating resistors  106 A and  106 B. 
     In essence, first control box assembly  100  is a junction box. In other words, race car  110  provides a power source. This power is delivered to ON/ON Switch  105 . When the ON/ON Switch  105  is moved to the AUTO position, power goes through a cable to the microswitch assembly  90  and to circuit breaker  107 . Then, power goes to power dissipating resistor  106 A and diode  108 A. Under these conditions; solenoid  81  is energized, assuming plunger  94  is contacting notch  73 , fuel flows to engine  60  of race car  110 . In addition, AUTO indicator light  103  is illuminated. 
     When ON/ON Switch  105  is in the MANUAL position, microswitch assembly  90  is by-passed. Except for microswitch assembly  90  being bypassed, first control box assembly  100  functions virtually the same way to energize solenoid  81 . Of course, power flows through power dissipating resistor  106 B and diode  108 B. As in the AUTO position, solenoid  81  is energized, assuming plunger  94  is contacting notch  73 , and fuel is flowing to engine  60  of race car  110 . In this situation, MANUAL indicator light  104  is illuminated. 
     FIG. 18 shows an alternative embodiment of the control box of the present invention. FIG. 18 shows second control box  100 A. With the exception of ON/ON switch  105  being remotely mounted, first control box  100  and  100 A are the same. Typically, second control box  100 A will be used in a situation where less space is available and only ON/ON switch  105  will be mounted on the dash board of race car  110 . In addition, in the preferred embodiment, second control box  100 A will be of dimensions 2 ½″×3 ½″×2″, which is smaller than first control box  100 . However, it is important that the driver of race car  110  be able to see AUTO light indicator  103  and MANUAL light indicator  104 . 
     As discussed above, electrical connection  99  communicates with fuel cut off assembly  80 . As discussed above, the final assembly of the present invention is a control box assembly. In this alternative embodiment this is second control box  100 A. Second control box assembly  100 A is seen in FIG.  18 . Second control box assembly  100 A is in turn connected to fuel cut off assembly  80  and microswitch assembly  90  as seen in FIG.  17 . Specifically, connector assembly  122  connects control boxes  100  and  100 A to Y connector  126 , seen in FIG.  17 . Connector assembly  122  includes Brad Harrison connectors and all cables are preferably made with a polyurethane outer jacket and are American Wire Gauge (AWG) size # 22 with 2, 3 or 4 conductors. As seen in FIGS. 15,  16 ,  17  and  18 , control boxs  100  and  100 A are connected to the ignition system by connector  124 . Connector  124  provides 12 volts to control box  100  or  100 A. 
     FIG. 17 shows wiring harness  120  that is used in conjunction with both first control box assembly  100  or second control box assembly  100 A. In other words, with both embodiments of the present invention. 
     As seen in FIGS. 17 and 18, the second control box assembly  100 A includes a remote an ON/ON switch  105 . This means that the solenoid will not be de-energized, and fuel cut off to the engine unless plunger  94  is not in contact with notch  73 , as discussed above. In other words, if the control box assembly is set to “AUTO,” this means that if race car  110  is subject to a collision which separates plunger  94  from notch  73 , solenoid  81  will instantly drop power and the flow of fuel through fuel line  30  will instantly be interrupted. 
     However, if any collision does not sufficiently damage race car  110  to prevent race car  110  from continuing the race, control box assembly  100 A can be set to “MANUAL.” When control box assembly  100 A is set to “MANUAL,” microswitch assembly  90  is bypassed and solenoid  81  is energized. As explained above, when solenoid  81  is energized, fuel can reach the engine  60 . Therefore, control box assembly  100 A is useful if race car  110  has suffered a small accident, which has urged plunger  94  out of contact with notch  73 , but is not sufficiently damaged to require race car  110  to leave the race. Of course, after suffering an accident, race car  110  would be “pitted” and plunger  94  could be pushed into contact with notch  73 . If plunger  94  and notch  73  cannot physically be brought into contact, the “MANUAL” position on control box assembly  100 A will energize solenoid  81  and allow fuel to flow. If for some reason the driver of race car  110  believes that there is an underhood fire, he or she can move the switch of control box assembly  100 A to the “AUTO” position and solenoid  81  will be de-energized and the flow of fuel interrupted because plunger  94  is not in contact with notch  73  and the circuit is “broken.” Because the circuit is “broken,” solenoid  81  will be de-energized and the flow of fuel interrupted. 
     FIG. 18 illustrates second control box assembly  100 A. Second control box assembly  100 A comprises cover  101 , base  102 , AUTO light indicator  103 , MANUAL light indicator  104 , ON/ON switch  105 , two power dissipating resistors  106 A and  106 B, circuit breaker  107 , diodes  108 A and  108 B and resistor  109 . Resistor  109  is a 3 ohm resistor which ensures that solenoid  81  does not receive greater than 12 volts at any given time. Because of the smaller size of second control box assembly  100 A, it is expected that it will be mounted beneath the dash board of race car  110  with only ON/ON switch  105  within reach of the driver. Specifically, cover  101  is preferably made with ABS plastic with a flammability rating of 94V—0 at 0.080″ thickness and a continuous use temperature of 70 degrees Centigrade. Typically, cover  101  will have a textured finish and dimensions of 2 ½″×3 ½″×2″. Base  102  will typically be made from aluminum and be about 0.125″ thick. Base  102  also serves as a backing plate and heat sink for power dissipation resistors  106 A and  106 B. Circuit breaker  107  is preferably an 3 ampere aircraft type circuit breaker. 
     FIG. 18 shows AUTO indicator light  103  and MANUAL indicator light  104  protruding through cover  101 . Power dissipating resistor  106 A and diode  108 A are associated with AUTO indicator light  103 . Similarly, power dissipating resistor  106 B and diode  108 B are associated with MANUAL indicator light  104 . The power dissipating resistors and diodes are necessary to prevent a foreshortened life for solenoid  81 . Specifically, the output voltage of a typical race car  110 &#39;s electrical system is 14.6 DC volts. Because solenoid  81  requires only 12 DC volts to operate, its life would be cut by about 75%. The power dissipating resistors are wrapped with wire, as seen in FIGS. 15 and 16. Combined with the base plate  102 &#39;s function as an aluminum, or other highly conductive metal, heat sink allows solenoid  81  to “see” no more than 12.07 DC volts. Preferably, the wire wrapped around power dissipating resistors  106 A and  106 B should be epoxy encapsulated in position. In addition, diodes  108 A and  108 B ensure that there is no current “back flow” through power dissipating resistors  106 A and  106 B. 
     In essence, second control box assembly  100 A is a junction box. In other words, race car  110  provides a power source. This power is delivered to ON/ON Switch  105 . When the ON/ON Switch  105  is moved to the AUTO position, power goes through a cable to the microswitch assembly  90  and to circuit breaker  107 . Then, power goes to power dissipating resistor  106 A and diode  108 A. Under these conditions; solenoid  81  is energized, assuming plunger  94  is contacting notch  73 , fuel flows to engine  60  of race car  110 . In addition, AUTO indicator light  103  is illuminated. 
     When ON/ON Switch  105  is in the MANUAL position, microswitch assembly  90  is by-passed. Except for microswitch assembly  90  being bypassed, second control box assembly  100 A functions virtually the same way to energize solenoid  81 . Of course, power flows through power dissipating resistor  106 B and diode  108 B. As in the AUTO position, solenoid  81  is energized, assuming plunger  94  is contacting notch  73 , and fuel is flowing to engine  60  of race car  110 . In addition, MANUAL indicator light  104  is illuminated. 
     FIG. 17 shows the interconnection of solenoid  81 , microswitch assembly  90  and control box  100  or  100 A by wiring harness  120 . Specifically, connector assembly  122  links control box  100  or  100 A to Y connector  126 . In the preferred embodiment, the bottom leg of Y connector  126  is a male five prong connector and the two arms of Y connector  126  are five prong female connectors. All connectors have a screw ring built into the housing of Y connector  126 . Connector  125  passes through front fire wall  50  and connects to connector  127 . Connector  127  connects to electrical connector  99 . In the preferred embodiment, electrical connector  99  is a “snap” type connector. Preferably, the “snap” type connector is a male connector which snaps into a female connector which is epoxied into microswitch assembly  90 . In addition, connector  129  connects Y connector  126  to solenoid  81 . As discussed above, if plunger  94  is not in electrical contact with notch  73 , the circuit is broken and solenoid  81  will not be energized and fuel flow will be instantly interrupted. 
     It is understood that the foregoing description and specific embodiments are merely illustrative of the best mode of the invention and the principles thereof, and that various modifications and additions may be made to the appartus by those skilled in the art, without departing from the spirit and scope of the invention, which is limited only by the scope of the appended claims.

Technology Category: 7