Abstract:
The disclosed apparatus relates to a current sensing electrical energy generation system comprising, an electric machine, a conductor electrically connected to the electric machine, and a current sensor responsive to current flow in the conductor.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of an earlier filing date from U.S. provisional application, 60/705,412, filed Aug. 4, 2005, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     An electrical system for a modern motor vehicle, among other items includes; a battery, an alternator, a regulator and a myriad of motors, sensors, computers, lights and other electronic devices which are interconnected with wiring. These electronic devices draw varying amounts of electrical current depending upon their function and how they are being utilized. The alternator/regulator assembly generates electrical current by converting rotational energy into electrical energy. An engine, typically through pulleys and belts, supplies the rotational energy to the alternator/regulator assembly. Therefore, whenever the engine is running, the alternator is rotating. 
     The torque required to rotate the alternator is proportional to the current that it is producing. A sudden increase in current production and the associated increase in torque required to rotate the alternator is significant enough to cause the engine speed to reduce by a few hundred RPM. These changes in engine RPM are perceived as poor idle quality and can cause a drop in fuel economy. It may be desirable to minimize the changes in engine RPM. Accordingly, there is a need for improvements in the art of alternator control. 
     SUMMARY OF THE INVENTION 
     The disclosed apparatus relates to a current sensing electrical energy generation system comprising, an electric machine, a conductor electrically connected to the electric machine, and a current sensor responsive to current flow in the conductor. 
     Further disclosed herein relates to a vehicle idle improvement system. The system comprising, an electric machine, a conductor electrically connected to the electric machine, a current sensor responsive to current flow in the conductor, and microprocessor type circuitry in operable communication with the electric machine and receptive to information obtainable from the current sensor. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Referring now to the drawings wherein like elements are numbered alike in the several Figures: 
         FIG. 1  is a prior art schematic of a vehicle electrical system; 
         FIG. 2  is a diagrammatic view of prior art connections used in vehicle alternator/regulator assembly systems; 
         FIG. 3  is a schematic of a vehicle electrical system disclosed herein; 
         FIG. 4  is a diagrammatic view of connections with a current sensor located near a ring terminal of B+ wire disclosed herein; 
         FIG. 5  is a diagrammatic view of an alternate embodiment with a current sensor located along the length of a B+ wire disclosed herein; 
         FIG. 6  is a plan view of an exemplary embodiment of a regulator assembly disclosed herein; 
         FIG. 7  is a partial cross sectional view of  FIG. 6  taken at arrows  7 - 7 ; and 
         FIG. 8  is a schematic of a vehicle electrical system employing the embodiment of  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG. 1  a prior art vehicle electrical schematic is shown generally at  1 . The vehicle electrical schematic comprising, an alternator/regulator assembly  6 , a battery  8 , vehicle electrical loads  10 , electronic control module (ECM)  12 , and grounds  13 . The alternator/regulator assembly  6  further comprising alternator  4  and regulator  5 . It will be appreciated that the ECM  12  controls the output of the alternator/regulator assembly  6  through wires  22  connecting the ECM  12  to the regulator  5 . The B+ wire  20  connects the output of the alternator/regulator assembly  6  to the battery  8  and the vehicle electrical loads  10 . A common ground  13 , grounds the alternator/regulator assembly  6 , the battery  8  and the vehicle electrical loads  10 . 
       FIG. 2  is a partial diagrammatic view of wiring connections for the schematic  FIG. 1  shown generally at  2 . A first end of the B+ wire  20  is terminated in a B+ wire ring terminal  40  for connection to an output stud of an alternator/regulator assembly  6 . The second end of the B+ wire  20  is connected to the battery  8  (not shown in  FIG. 2 ). An injection molded two-way female insulator  30  is fixedly attached to a body of the alternator/regulator assembly  6  (not shown in  FIG. 2 ). Terminals within the two-way female insulator  30  are electrically connected internally to the regulator  5  of the alternator/regulator assembly  6 . An injection molded two-way male insulator  31 , connectable with the two-way female insulator  30 , retains two terminals (not shown) that are crimped to the first ends of a pair of wires  22  that have a second end electrically connected to the ECM  12 . When the two-way male insulator  31  is connected to the two-way female insulator  30  their pairs of terminals electrically engage and an electrical circuit is completed between the regulator  5  and the ECM  12  such that electrical communication can take place between the regulator  5  and the ECM  12 . 
     Referring to  FIG. 3  a vehicle electrical schematic in accordance with an embodiment of the invention is shown generally at  7 . The vehicle schematic  7  includes a current sensor  50  at the B+ wire  20 , which connects output of the alternator/regulator assembly  16  to the battery  8  and to the vehicle electrical loads  10 . The current sensor  50  is in electrical communication with the regulator  15  through wires  24 ,  26 . The current sensor  50  can employ any of a variety of methods known in the art for measuring the current flowing through a conductor without deviating from the invention, such as; a sense resistor, a current transformer or a Hall effect sensor, for example. Two-way electrical communication between the regulator  15  and the ECM  12  is completed through wires  22 . A common ground  13 , grounds the alternator/regulator assembly  16 , the battery  8  and the vehicle electrical loads  10 . A diagrammatic view of several connections in  FIG. 3  can be found in  FIG. 4 . 
       FIG. 4  shows a partial diagrammatic view of the wiring connections of the schematic of  FIG. 3  shown generally at  18 . The current sensor  50  is shown over-molded with resin  52  around the B+ wire  20  near the alternator B+ wire ring terminal  40 . A pair of wires  24  have first wire ends  25  connected to the circuit of the current sensor  50  which protrude from the over-molded resin  52  encasing the current sensor  50 . The second ends  27  of wires  24  are connected into terminals (not shown) that are retained in an injection molded two-way female insulator  32 . The two-way female insulator  32  is removably attached to a mating injection molded two-way male insulator  33 . Terminals (not shown) retained within the two-way male insulator  33  are crimped to first ends  29  of wires  26 , the second ends  31  of wires  26  are crimped into terminals that are retained within an injection molded four-way male insulator  35  that mates with injection molded four-way female insulator  34 . The four-way female insulator  34  is fixedly attached to the alternator/regulator assembly  16 , which houses a processing circuit  42 , which includes current control circuitry for controlling current in the electric machine. The four terminals of the four-way female insulator  34  are in electrical communication with the processing circuit  42 . The remaining two terminals retained in the four-way male insulator  35  are electrically connected to first ends  33  of wires  22 , the second ends  37  of wires  22  are in electrical communication with the ECM  12 . 
     The processing circuit, through the connections thus described, is in electrical communication with the ECM  12 , the regulator  15 , and the current sensor  50 . Through these connections the current output of the alternator/regulator assembly  16  can be used as input to the ECM  12  as a control variable. It should be understood that various wire routings and connector configurations, for example, could be employed without deviating from the present invention. 
     Referring now to  FIG. 5 , an alternate embodiment of the invention is shown in diagrammatic view shown generally at  38 . In this embodiment a current sensor  51  is located along a length of a B+ wire  20  remote from the B+ wire ring terminal  40 . Locating the current sensor  51  remotely from the ring terminal  40  addresses concerns of space limitations near the output terminal of the alternator/regulator assembly  16  that may not accommodate the addition of a current sensor  50  of the earlier described embodiment. 
     Referring to  FIGS. 6 and 7 , an exemplary embodiment of a regulator assembly disclosed herein is depicted at  65 . The regulator assembly  65  is structurally connected to the alternator  44  ( FIG. 8 ) and provides electrical connections to electrically interface the alternator  44  to the vehicle electrical system or ECM  12 . The regulator assembly  65  is structurally mounted to the alternator  44 . A fastener  67  shown herein as a screw, threadably attaches one end of an elongated body  62  of the regulator assembly  65  through a first hole  66  therein. A second hole  64  on an opposite end of the body  62  receives an alternator B+ output stud  61  upon which is threadably engaged a nut  82  that compresses a spacer  69  onto a lead frame  72 . The spacer  69  may be made of metal, or other electrically conductive material for example, to assist in completing an electrical connection between the B+ stud  61  and the lead frame  72  in addition to providing the structural mounting for the regulator assembly  65  to the alternator  44 . The B+ stud  61  protrudes through and is fixedly attached to a support plate  63  of the alternator  44 . 
     The electrical interface of the regulator assembly  65  to the alternator occurs through terminals  68  and  70  as well as through the B+ stud  61  to the lead frame  72  structural connection described above. Additionally, the regulator assembly  65  comprises a current sensor  76  to measure the current flow through the B+ stud  61 . A core  78  of the current sensor  76  is overmolded with resin  79  to electrically insulate it from the B+ stud  61 , the spacer  69  and the lead frame  72 . Leads  84  and  86  from the core  78 , of the current sensor  76 , are electrically connected to the current sensor processing circuit  80  housed within the regulator assembly  65 . Additionally the leads  84  and  86  are overmolded with resin  79  with the rest of the regulator body  62  and the current sensor  76 . The current sensor  76  shown in this exemplary embodiment is of the Hall effect type, however other current sensing methods may be employed. 
     The regulator assembly  65  also provides electrical communication to the ECM  12 . An injection molded two-way female insulator  30  is fixedly attached to the body  62  of the regulator assembly  65 . An injection molded two-way male insulator  31  connectable with the two-way female insulator  30  electrically connects the regulator assembly  65  with bi-directional communication via wires  22  with the ECM  12  as shown in a vehicle schematic  90  in  FIG. 8 . B+ wire  20  electrically connects the B+ stud  61  of the alternator  44  to the battery  8  and the vehicle electrical loads  10 . A common ground  13  provides ground to the alternator  44 , the battery  8  and the electrical loads  10 . 
     Packaging the current sensor core  78  around the B+ stud  61  and housing the processing circuit  80  within the regulator assembly  65 , permits the addition of the current sensing feature and the current control circuitry without requiring physical changes to the vehicle, thereby avoiding cost increases associated with adding a stand alone current sensor that would require additional wire connections as well as a housing for the current sensor. 
     While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best or only mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.