Abstract:
An engine stopping/starting control unit having improved accelerating performance. A charging limiting device is provided which limits the charge provided to a generator when the vehicle is stopped. The decreased charging allows for better performance when the vehicle accelerates from a stopped states. Also, the vehicle headlight can be dimmed while the vehicle is stopped, which reduces the load on the generator. An acceleration detector detects when the vehicle accelerates during running, and can decrease the generator load in response to the acceleration.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a vehicle including an engine stopping/starting control unit for interrupting, during running, ignition control of an engine under a specific vehicle stopping condition, and re-starting, after interruption, the ignition control of the engine in response to a specific vehicle moving operation. Particularly, an engine stopping/starting control unit is disclosed with improved accelerating performance upon vehicle movement. 
     2. Background Art 
     An engine stopping/starting control unit intended to suppress the emission of exhaust gas, particularly upon idling, and fuel consumption, has been disclosed. One such unit is disclosed in Japanese patent Laid-open No. Sho 63-75323. In this patent, the control unit performs such that when a vehicle is stopped, the engine is automatically stopped, and when a throttle grip is operated to move the vehicle, the engine is automatically restarted to move the vehicle. 
     In a light vehicle, such as a motorcycle or a three-wheeled vehicle, it may be desirable to use a head lamp in the daytime as well as in the nighttime. This can cause problems when the light vehicle moves from the stopped position. Because activation of the head lamp increases the power requirement from the generator, the required driving torque of the generator is correspondingly increased. As a result, the vehicle in which the head lamp is left on has an increased mechanical load on the engine. This negatively affects accelerating performance. 
     To solve the above problem, a technique has been disclosed in Japanese Patent Laid-open No. Sho 58-179134, in which the power generation amount of a generator is lowered upon rapid acceleration in order to reduce the load on the engine, thereby ensuring sufficient accelerating performance. 
     For a light vehicle such as a motorcycle or a three-wheeled vehicle, it may also be desirable to keep the head lamp on for improved visibility to the opposite lane during running and upon vehicle stop, such as at a stoplight. 
     For the vehicle including the engine stopping/starting control unit, however, since the engine is automatically stopped upon vehicle stop, if the head lamp is left on, a discharge of the battery rapidly proceeds. As a result, upon vehicle movement after automatic stoppage, the power generation amount of the generator is increased, so that the load of the engine is correspondingly increased, thereby reducing accelerating performance. 
     As described above, for the vehicle including the engine stopping/starting control unit in which the head lamp is left on upon vehicle stop, there arises the problem that sufficient accelerating performance cannot be obtained upon rapid acceleration during running and upon vehicle movement after automatic stoppage of the engine. 
     SUMMARY OF THE INVENTION 
     The present invention addresses the problems associated with the conventional art and obtains other advantages not contemplated by the conventional art. 
     The present invention includes an engine stopping/starting control unit in which a head lamp is left on during vehicle stop, and in which a desirable accelerating performance is obtained even upon vehicle movement after automatic engine stoppage. 
     To achieve the above object, a vehicle includes an engine stopping/starting control unit for interrupting, during running, ignition control of the engine under a specific vehicle stopping condition, and, restarting, after interruption, the ignition control of the engine in response to a specific vehicle moving operation. The vehicle includes the following desirable characteristics: 
     (1) the engine stopping/starting control unit includes: a vehicle moving operation detector for detecting a vehicle moving operation, and a charging limiting device for limiting charging from a generator into a battery for a specific period of time if it detects the vehicle moving operation; 
     (2) the engine stopping/starting control unit further includes an acceleration detector for detecting an acceleration performed by a driver during running, and the charging limiting device limits the charging from the generator into the battery for the specific period of time if acceleration or vehicle movement is detected by either the acceleration detector or the vehicle moving operation detector; 
     (3) the engine stopping/starting control unit further includes a regulator for controlling the voltage outputted from the generator to a charging voltage and supplying the charging voltage to the battery, and the charging limiting device limits the charging by reducing the charging voltage of the regulator; and 
     (4) the engine stopping/starting control unit further includes a switch for controlling the supply of power to a head lamp of the vehicle, and a head lamp control device for controlling opening/closing of the switch. When the ignition control of the engine is interrupted, the head lamp control device interrupts the switch to substantially reduce the voltage applied to the head lamp. 
     According to feature (1), when the vehicle moving operation is detected, the charging from the generator to the battery is limited to reduce the electrical load of the generator. Accordingly, since the torque required for the engine to drive the generator is reduced, the accelerating performance is improved. Also, because the charging from the generator to the battery, upon vehicle movement from vehicle stop, is not interrupted but only limited, the head lamp does not become dark upon vehicle movement from vehicle stop. 
     According to the feature (2), the accelerating performance can be improved not only upon vehicle movement from vehicle stop, but also acceleration during running. 
     According to the feature (3), the charging limitation upon vehicle movement after vehicle stop, or upon acceleration, can be simply performed by control of a voltage of the regulator. 
     According to the feature (4), when the ignition control of the engine is interrupted upon vehicle stop and the engine is automatically stopped, the voltage applied to the head lamp is substantially reduced. Accordingly, the discharge of the battery can be suppressed without turning the head lamp off. As a result, since the amount of charging from the generator to the battery can be reduced upon the subsequent vehicle movement, the electrical load of the generator is reduced. This improves the accelerating performance upon vehicle movement. 
    
    
     Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: 
     FIG. 1 is a side view showing a scooter-type motorcycle on which an engine stopping/starting control system according to the present invention is mounted; 
     FIG. 2 is a plan view of an instrument panel on a scooter-type motorcycle; 
     FIGS.  3 ( a ) and  3 ( b ) are sectional views of a throttle grip; 
     FIG. 4 is a view of the outline of a seating state detecting unit; 
     FIG. 5 is a sectional view taken on line II—II in FIG. 1; 
     FIG. 6 is a block diagram of a starting/stopping control system according to a first embodiment of the present invention; 
     FIG. 7 is a block diagram showing the function of a main control unit; 
     FIG. 8 is a block diagram, continued from that shown in FIG. 7, showing the function of the main control unit; 
     FIG. 9 is a chart of operations of the main control unit; 
     FIG. 10 is a diagram of the conditions for switching operational modes and operational patterns; 
     FIG. 11 is a block diagram of a starting/stopping control system according to a second embodiment of the present invention; 
     FIGS.  12 ( a ) and  12 ( b ) are enlarged sectional views of the seating state detecting unit at a non-seating position; 
     FIG. 13 is a perspective view of a link member contained in the seating state detecting unit; 
     FIG. 14 is an enlarged view of a second hinge shaft; 
     FIG. 15 is an enlarged sectional view of the seating state detecting unit at a seating position; 
     FIG. 16 is an enlarged sectional view of the seating state detecting unit at a position where a seat is raised to open a luggage box; 
     FIG. 17 is an enlarged sectional view of an example of the seating state detecting unit in which the second hinge shaft is configured as a shaft having a circular cross-section; 
     FIG. 18 is an enlarged sectional view of an example of the seating state detecting unit in which a coil spring is disposed on the vehicle side; 
     FIGS.  19 ( a ) and  19 ( b ) are sectional views of a link member biasing element; 
     FIG. 20 is an enlarged sectional view of an example of the seating state detecting unit in which the coil spring is fixed on the seat side; 
     FIG. 21 is a block diagram of a variation of the starting/stopping control system shown in FIG. 6; and 
     FIG. 22 is a chart of operations of a main control unit of the variation shown in FIG.  21 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 is a side view of a scooter-type motorcycle  1 . A body front  2  is connected to a body rear  3  via a low floor  4 . A body frame, which constitutes the skeletal structure of a vehicular body, basically includes a down tube  6  and a main pipe  7 . A fuel tank and a containing box (both not shown) are supported by the main pipe  7 , and a seat  8  is disposed over the fuel tank and the containing box. The seat  8  serves as a luggage box provided on the underside of the seat  8 , and is configured to be turnable by a hinge mechanism provided on a front portion FR of the seat  8  for opening/closing the luggage box. 
     At the body front  2 , a handlebar  11  is rotatably supported by a steering head  5  so as to extend upwardly therefrom, and a front fork  12  is also rotatably supported by the steering head  5  so as to extend downwardly therefrom. A front wheel  13  is rotatably supported by the lower end of the front fork  12 . The upper portion of the handlebar  11  is covered with a handle cover  33  serving as an instrument board. A bracket  15  projects from the lower end of a rising portion of the main pipe  7 , and a swing unit  17  is swingably connected to and supported by the bracket  15  via a link member  16 . 
     A single-cylinder/two-stroke internal combustion engine  200  is mounted on the front portion of the swing unit  17 . A belt-type continuously variable transmission  35  extends rearwardly from the internal combustion engine  200 . A reduction mechanism  38  is provided on the rear portion of the belt-type continuously variable transmission  35  via a centrifugal clutch, and a rear wheel  21  is rotatably supported by the reduction mechanism  38 . A rear cushion  22  is interposed between the upper end of the reduction mechanism  38  and an upper curved portion of the main pipe  7 . A carburetor  24  is connected to an intake pipe  23  and extends from a cylinder  32  of the internal combustion engine  200 . An air cleaner  25  is connected to the carburetor  24  and is disposed on the front portion of the swing unit  17 . 
     A main stand  26  is pivotably mounted on a hanger bracket  18  projecting from the lower portion of a unit swing case  31 . The base end of a kick arm  28  is fixed on a kick shaft  27  projecting from a transmission case cover  36  of the belt-type continuously variable transmission  35 , and a kick pedal  29  is provided at the leading end of the kick arm  28 . 
     FIG. 2 is a plan view of the instrument panel of the scooter-type motorcycle  1 . The instrument panel  90  provided on the handle cover  33  includes a speedometer  91 , a stand-by indicator  56 , and a battery indicator  76 . As will be described in detail later, the stand-by indicator  56  flashes upon engine stop under engine stopping/starting control, to warn the driver that if a throttle is opened, the engine is immediately started, thereby allowing movement of the vehicle. The battery indicator  76  flashes if the battery voltage is lowered to a specified value, to warn the driver of a shortage of the charged amount of power in the battery. 
     The handle cover  33  is provided with an idle switch  53  for permitting or limiting idling, and a starter switch  58  for starting a starter motor. The right end portion of the handlebar  11  has a throttle grip  92  and a brake lever  93 . In addition, a root portion of each of the right and left throttle grips includes a horn switch, a blinker switch, and the like as in a conventional motorcycle (not shown). 
     FIG.  3 ( a ) is a sectional view showing a main portion of the throttle grip  92 , and FIG.  3 ( b ) is a sectional view taken on line I—I of FIG.  3 ( a ). As shown in FIG.  3 ( a ), a throttle grip main body  182  is turnably inserted around a handle pipe  181 , and the outer periphery of the throttle grip main body  182  is covered with a grip cover  183 . The throttle grip main body  182  has a circumferential flange  182   a , and as shown in FIG.  3 ( b ), one end  185   a  of a throttle wire  185  is locked with the flange  182   a . The throttle grip main body  182  is usually biased by the elastic force of a spring  184  in the direction of closing an accelerator. 
     When the throttle grip main body  182  is twisted by the driver in the direction of opening the accelerator against the elastic force of the spring  184 , the throttle wire  185  is wound in to open the throttle. With respect to the turning motion of the throttle, play is given as an idle turning motion. Accordingly, when the turning motion of the throttle grip  92  exceeds the range of the play, the throttle is opened. 
     A projection  51  is formed on the flange  182   a , and a throttle switch  52  is provided so as to be turned on/off when the projection  51  goes away from or comes in contact with the throttle switch  52 . When the throttle grip main body  182  is opened from the position shown in FIG.  3 ( b ) by a specific angle within a play angle range θ, the throttle switch  52  closes the contact, that is, it is turned on. To be more specific, when the flange  182   a  is rotated by the specific angle within the play angle range θ in the direction of opening the throttle, the throttle switch  52  is turned on to start the starter, and when the flange  182   a  is further rotated to an extent that the rotating angle exceeds the play angle range θ, the throttle is actually opened. 
     The driver can maintain the vehicle stopped state while rotating the engine, by fixing the throttle grip  92  at a position where the turning angle thereof exceeds the play angle range θ. The above configuration of the throttle switch  52  is for illustrative purposes only, and therefore, the present invention is not limited thereto. For example, the throttle switch  52  may be configured to be turned on concurrently with or after the throttle is actually opened. 
     A throttle spring (not shown) is provided. This has an effect on the throttle in the direction of closing the throttle. To be more specific, the throttle spring is biased in the direction where the throttle grip is  14  closed. Accordingly, since the repulsive force of the throttle spring acts even within the play angle range θ, the throttle switch  52  is automatically closed even within the play angle range θ in which there is no return force of the throttle wire  185 . 
     The throttle switch  52  may be replaced with a throttle opening sensor. In this case, a throttle full-close position decided by the throttle opening sensor corresponds to the turn-off state of the throttle switch  52 , and positions other than the throttle full-close position decided by the throttle opening sensor corresponds to the turn-on state of the throttle switch  52 . The use of the throttle opening sensor in place of the throttle sensor  52  makes it possible to accurately perform charging control to be described later. 
     FIG. 5 is a sectional view taken on line II—II of the internal combustion engine  200  shown in FIG.  1 . The internal combustion engine  200  is configured such that a cylinder block  203  and a cylinder head  204  are sequentially assembled to a crank case  202  divided into right and left crank cases  202 R and  202 L. A crank shaft  201  extending from right to left in the horizontal direction is rotatably supported by the right and left crank cases  202 R and  202 L. The cylinder block  203  has an exhaust passage (not shown) and scavenging passages  205  extending from scavenging ports opened in a cylinder bore, to be thus communicated to a crank chamber of the crank case  202 . 
     An ignition plug  206  facing to a combustion chamber is inserted in the cylinder head  204 . The cylinder head  204  and the cylinder block  203  are covered with a fan shroud  207  except for the exposed portion of the ignition plug  206 . The left crank case  202 L serves as a belt-type continuously variable transmission case, and a belt drive pulley  210  is provided on the crank shaft  201  passing through the left crank case  202 L so as to be rotatable with the crank shaft  201 . 
     The belt drive pulley  210  is composed of a fixed side pulley half  210 L and a movable side pulley half  210 R. The fixed side pulley half  210 L is fixed at a left end portion of the crank shaft  201  via a boss  211 , and the movable side pulley half  210 R positioned on the right side of the fixed pulley half  210 L is spline-connected to the crank shaft  201 . The movable side pulley half  210 R is movable close to or apart from the fixed side pulley half  210 L. A V-belt  212  is wound between both the pulley halves  210 L and  210 R. 
     A cam plate  215  is positioned on the right side of the movable side pulley half  210 R and is fixed on the crank shaft  201 . A slide piece  215   a  provided on the outer peripheral edge of the cam plate  215  is slidably engaged with a cam plate sliding boss  210 R a  which is formed at the outer peripheral edge of the movable side pulley half  210 R so as to extend outwardly therefrom in the axial direction. The outer peripheral side of the cam plate  215  of the movable side pulley half  210 R has a taper plane tilted on the cam plate  215  side, and a dry weight ball  216  is contained in a space between the taper plane and the movable pulley half  210 R. 
     As the rotational speed of the crank shaft  201  is increased, the dry weight ball  216  between the movable side pulley half  210 R and the cam plate  215  is rotated therewith to be thus moved in the centrifugal direction by a centrifugal force applied thereto, whereby the movable side pulley half  210 R is pushed by the dry weight ball  216  to be moved left toward the fixed side pulley  17  half  210 L. The V-belt  212  held between both the pulley halves  210 L and  210 R is thus moved in the centrifugal direction. This results in an increase in winding radius of the V-belt  212 . 
     A driven pulley (not shown) corresponding to the belt drive pulley  210  is provided on the rear portion of the vehicle. The V-belt  212  is also wound around the driven pulley. The power of the internal combustion engine  200  is automatically adjusted and is transmitted to a centrifugal clutch by the belt-transmission mechanism, to be used for driving the rear wheel  21  via the reduction mechanism  38  and the like. 
     A transmission case cover  220  extends rearwardly from the belt drive pulley  210  and covers, from left, the belt-type continuously variable transmission chamber. The kick shaft  27  is turnably supported by the front portion of the transmission case cover  220  in a state in which it passes therethrough. The kick shaft  27  is biased by a return spring  223 . A drive helical gear  222  is fitted around an end portion, positioned inside the transmission case cover  220 , of the kick shaft  27 . A sliding shaft  224  is supported by the transmission case cover  220  so as to be coaxial with the crank shaft  201  and to be rotatable and axially slidable relative to the transmission case cover  220 . A driven helical gear  225  meshing with the drive helical gear  222  is formed on the sliding shaft  224 . A ratchet wheel  226  is fixed at the right end (in FIG. 5) of the sliding shaft  224 . The sliding shaft  224  thus provided with the driven helical gear  225  and the ratchet wheel  226  is entirely biased left in FIG. 5 by a friction spring  227 . 
     A ratchet to be engaged with the ratchet wheel  226  is formed on a boss  211  provided on the crank shaft  201 . The ratchet wheel  226  can be brought in contact with or separated from the ratchet by sliding motion of the sliding shaft  224  relative to the transmission case cover  220 . When the kick pedal  29  is actuated and the kick shaft  27  is rotated against the biasing force of the return spring  223 , the drive helical gear  222  is rotated integrally with the kick shaft  27 , so that the driven helical gear  225  meshing with the drive helical gear  222  is rotated integrally with the sliding shaft  224  and is slid on the boss  211  side against the biasing force of the friction spring  227 . As a result, the ratchet wheel  226  is meshed with the ratchet of the boss  211 , to forcibly rotate the crank shaft  201 , thereby starting the internal combustion engine  200 . 
     The right crank case  202 R, formed into an approximately cylindrical shape, extends rightwardly from a main bearing  209  which rotatably supports the crank shaft  201 . The crank shaft  201  projects along the center axis of the right crank case  202 R. A starter/generator  250  including a starter and an AC generator combined with the starter is disposed in the cylinder body of the right crank case  202 R. 
     An inner rotor (rotational inner magnet type rotor)  251  is fitted around a taper portion at the leading end of the crank shaft  201  and is fixed thereto by way of a nut  253 . Accordingly, the inner rotor  251  is rotatable integrally with the crank shaft  201 . The outer peripheral surface of the inner rotor  251  has six grooves each being formed into a circular-arc shape in cross-section. A magnet  271  made from a neodymium-iron-boron alloy is fitted in each groove of the inner rotor  251 . 
     An outer stator  270  disposed around the outer periphery of the inner rotor  251  is supported by screwing a bolt  279  passing through the outer peripheral edge of the outer stator  270  in a cylindrical wall  202   a  of the crank case  202 . A stator core of the outer stator  270  is composed of stacked steel thin plates, and a generating coil  272  and a starting coil  273  are wound around a plurality of teeth extending in the center direction from the stacked steel thin plates. The generating coil  272  and the starting coil  273  are wound around the teeth so as to be offset inwardly in the crank shaft direction. In other words, the amounts of the coils  272  and  273  projecting outwardly in the axial direction are made small. 
     The generating coil  272  and the starting coil  273  project larger axially inwardly than outwardly in the cylindrical wall  202   a  of the crank case  202 , to form an annular shape. A commutating brush mechanism  263  is provided in an inner space formed in the above annular shape of the coils  272  and  273 . A brush holder  262  allowing the crank shaft  201  to pass therethrough in the above inner space is fitted around the crank shaft  201  so that the circumferential rotation thereof relative to the crank shaft  201  is prohibited and only the axial sliding motion thereof relative to the crank shaft  201  is permitted. The brush holder  262  is biased axially inwardly by a spring  274  interposed between the inner rotor  251  and the brush holder  262 . 
     Brushes  263  are provided at a plurality of specific locations of the inner surface of the brush holder  262  so as to be biased by a spring and to project therefrom. A commutator holder  265  is provided so as to face to the inner surface of the brush holder  262 . The crank shaft  201  passes through the central portion of the commutator holder  265 . The outer peripheral edge of the commutator holder  265  is fixedly supported by the portions, largely projecting inwardly in the axial direction, of the generating coil  272  and the starting coil  273 . 
     Commutator pieces  267  are concentrically disposed at specific locations of the surface, opposed to the brush holder  262 , of the commutator holder  265 . The brush holder  262 , which is rotatable integrally with the crank shaft  201 , can be moved close to or apart from the fixed commutator holder  265 . When the brush holder  262  is moved close to the commutator holder  265 , the brushes  263  are brought in contact with the associated commutator pieces  267 . 
     An inner cylindrical portion  231  and an outer cylindrical portion  232  extend axially outwardly from the outer end of the inner rotor  251  in the crank shaft direction. The inner cylindrical portion  231  covers the surrounding of the nut  253  screwed in the leading end of the crank shaft  201 , and the outer cylindrical portion  232  coaxially covers the outer side of the inner cylindrical portion  231 . A governor mechanism  230  is provided between the inner cylindrical portion  231  and the outer cylindrical portion  232 . To be more specific, the inner peripheral surface of the outer cylindrical portion  232  is tapered, and such a taper portion is taken as a governor outer; a governor inner  233  is axially slidably fitted to the outer periphery of the inner cylindrical portion  231 ; and a governor weight ball  234  is interposed between the governor inner  233  and the outer cylindrical portion  232 . 
     A connecting shaft  235  with its one end fixed to the axially slidable governor inner  233  of the governor mechanism  230  passes through the inner rotor  251  in parallel to the crank shaft  201 , and the leading end of the connecting shaft  235  is fitted to the brushed holder  262 . The connecting shaft  235 , which connects the governor inner  233  to the brush holder  262 , is movable together with the governor inner  233  and the brush holder  262  in the crank shaft direction. 
     When the crank shaft  201  is stopped, the brush holder  262  is biased axially inwardly by the biasing force of the spring  223  so that the brushes  263  are in contact with the commutator pieces  267 . Accordingly, in this state, a current supplied from the battery flows in the starting coil  273  via the contact portions of the brushes  263  with the commutator pieces  267 , to create a rotational torque of the inner rotor  251 . As a result, the crank shaft  201  is rotated by such a rotational torque of the inner rotor  251 , to thereby start the internal combustion engine  200 . 
     As the rotation rate of the engine is increased, the ball  234  is moved toward the outer periphery along the tapered inner surface of the outer cylindrical portion  232 , so that the governor inner  233  is slid axially outwardly and the brush holder  262  is moved axially outwardly together with the governor inner  233  via the connecting shaft  235 . As a result, when the rotation rate of the engine exceeds a specific value, the brushes  263  are automatically moved apart from the commutator pieces  267 . After that, the battery is charged by the generating coil  272 . 
     An annular plate like rotor  240  for detecting a crank angle is provided on the edge portion of the outer cylindrical portion  232  constituting part of the governor mechanism  230  so that the inner peripheral edge of the rotor  240  is integrally fitted thereto. A pulser  241  is disposed at a specific position near the outer peripheral edge of the rotor  240 . Repeated notches formed in the outer peripheral edge of the rotor  240  rotated together with the crank shaft  201  via the inner rotor  251  are detected by the pulser  241 , to thereby decide the crank angle. The annular plate like rotor  240  covers the outer sides of the generating coil  272  and the starting coil  273  of the outer stator  270 . A fan member  280  for forcibly air-cooling the internal combustion engine is integrally provided on the rotor  40  so as to project axially outwardly therefrom. 
     The fan member  280  is configured such that the skirt portion of a central cone portion  280   a  is fixed to the outer cylindrical portion  232  of the inner rotor  251  with a bolt  246  and a fan  280   b  provided on the outer periphery of the skirt portion is erected outside the rotor  240 . The fan member  280  is covered with a fan cover  281 . 
     The starter/generator for a vehicle in this embodiment, having the above-described configuration, exhibits the following effects. Since the commutator brush mechanism  263  is disposed axially inwardly of the inner rotor  251  and the governor mechanism  230  separated from the commutator brush mechanism  263  is disposed axially outwardly of the inner rotor  251 , the amounts of components extending outwardly in the crank shaft direction can be made small. 
     Since the generating coil  272  and the starting coil  273  are wound around the teeth of the stator core of the outer stator  270  so as to be offset inwardly than outwardly in the axial direction, the amounts of the coils  272  and  273  projecting outwardly in the axial direction are made small. As a result, it is possible to suppress the axially outwardly swelled amounts of the rotor  240  and the fan member  280  located outside the coils  272  and  273 , and hence minimize the amounts of the components swelled outwardly in the crank shaft direction. 
     Outside air, which is introduced in the fan cover  281  through an outside air inlet  281   a  formed in the fan cover  281  by rotation of the fan  280   b , is spread toward the outer peripheral side along the central cone portion  280   a . However, the outside air thus spread toward the outer peripheral side is cut off by the rotor  240 , and thereby permeates on the starter/generator  250  side. The outside air thus hardly permeates in the commutator brush mechanism  263  located more deeply than or axially inwardly from the starter/generator  250 . The result is that the commutator brush mechanism  263  is prevented from being affected by dust contained in the outside air. 
     FIG. 4 is a view of the hinge portion for opening/closing the seat  8 . The configurations of a hinge portion for opening/closing the seat  8  and a seating switch disposed near the hinge portion will be described below. The seat  8  serving as a lid of the luggage box  9  provided under the seat  8  is provided so as to be openable/closable in the direction shown by an arrow A relative to the luggage box  9 . The seat  8  can be opened/closed via a hinge shaft  102  and a link member  100  which are both provided on the luggage box  9 . The link member  100  is swingable around the hinge shaft  102 . The other end, opposed to the end connected to the hinge shaft  102 , of the link member  100 , is turnably connected to a second hinge portion  110  provided on a frame  8   a  of the seat  8 . As a result, the seat  8  can be swung around the hinge shaft  102  in the direction shown by the arrow A and can be also swung around the second hinge shaft  110  in the direction shown by an arrow B. 
     A spring  103  is interposed between the link member  100  and the frame  8   a  for biasing the seat  8  clockwise around the second hinge shaft  110 . A seating switch  54  is also provided between the link member  100  and the frame Ba. When the driver is seated on the seat  8  and the frame Ba is turned by a specific amount counterclockwise around the second hinge shaft  110 , the seating switch  54  is turned on for detecting the seating state. 
     An example of the structure whose principle is shown in FIG. 4 will be described below. FIGS.  12 ( a ) and  12 ( b ) are enlarged sectional views of the front portion of the seat  8 , illustrating a first position state in which the driver is not seated on the seat  8 . Referring to FIGS.  12 ( a ) and  12 ( b ), a bearing  101  for supporting the link member  100  is provided to the luggage box  9 . The hinge shaft  102  passes through the bearing  101 , and both ends of the hinge shaft  012  pass through the link member  100  and support the link member  100 . The link member  100  supported by the bearing  101  is swingable around the hinge shaft  102  in the direction shown by the arrow A. 
     Bolts  111 , which are planted in the frame  8   a  of the seat  8 , pass through holes (to be described later) provided in the other end portion of the link member  100  and are screwed with nuts  112 . That is to say, the link member  100  is held between the nuts  112  and the underside of the frame  8   a . The portion, held between the underside of the frame  8   a  and the nuts  112 , of the link member  100  is partially bent downwardly and upwardly into two V-shapes and an inverse V-shape therebetween. The vertexes of the V-shaped portions of the link member  100  are in nearly line-contact with the nuts  112 , and the vertex of the inverse V-shaped portion of the link member  100  is in nearly line-contact with the frame  8   a.    
     The shapes of the bent portions of the link member  100  will be described in detail with reference to FIGS. 13 and 14. In this way, the frame  8   a  is in line-contact with the vertex of the inverse V-shaped portion of the link member  100 , and the line-contact portion forms a fulcrum corresponding to the above-described second hinge shaft  110  for swingably supporting the frame  8   a  of the seat  8  in the direction shown by the arrow B. 
     The link member  100  contains a coil spring  103 , and a set plate  104  is provided at one end (lower end) of the coil spring  103  and a cap  105  is provided at the other end (upper end) of the coil spring  103 . The set plate  104  is supported by holes (to be described later) formed in the side surfaces of the link member  100 . The cap  105  projects onto the seat  8  side from a hole formed in the upper surface of the link member  100 . The projecting amount of the cap  105  is restricted by a flange portion of the cap  105 . To be more specific, the cap  105  (which is elastically biased by the repulsive force of the coil spring  103 ) projects from the upper surface of the link member  100  by a specific amount, thereby lifting the frame  8   a  of the seat  8 . 
     The frame  8   a  has a dowel  8   b  which projects in the link member  100  through another hole formed in the upper surface of the link member  100 . The seating switch  54  is mounted on the luggage box  9  by way of a mounting fixture  54   a , and the leading end of a spindle  54   b  (functioning as an actuator displaced in the seating switch  54 ) faces to the dowel  8   b.    
     The dowel  8   b  has, as shown in FIG.  12 ( b ), a shaft portion S and an overhang portion F. The upper end surface of the overhang portion F is engaged with the underside of the link member  100 , to thereby restrict the upwardly swing motion of the seat  8  in the direction shown by the arrow B. 
     FIG. 13 is a perspective view of the link member  100 . Both the side surfaces of the link member  100  have holes  102   a  for supporting both the ends of the hinge shaft  102  and holes  104   a  for supporting both the ends of the set plate  104 . The upper surface of the link member  100  has an approximately rectangular hole  80   b  allowing the dowel  8   b  to pass therethrough, and a round hole  105   a  allowing the top of the cap  105  to pass therethrough. Further, a central portion  100   a  of the link member  100  is upwardly bent into an inverse V-shape, and both end portions  100   b  of the link member  100  are downwardly bent into V-shapes. The inverse V-shaped portion  100   a  and the V-shaped portions  100   b  form a fulcrum corresponding to the above-described second hinge shaft  110 . 
     The vertex or ridge P of the inverse V-shaped portion  100   a  comes into contact with the underside of the frame  8   a , and the vertexes formed on the back faces of the V-shaped portions  100   b  (located on the back faces of the valley portions V) come into contact with the nuts  112 . In addition, the nuts  112  are preferably brought into contact with the vertexes of the V-shaped portions  100   b  via cushioning rubber washers. The V-shaped portions  100   b  have holes  111   a  allowing the bolts  111  to pass therethrough. 
     The function of the portions  100   a  and  100   b  taken as the fulcrum corresponding to the second hinge shaft  110  upon swing motion of the link member  100  will be described in detail with reference to FIGS. 14 to  16 . 
     FIG. 14 is an enlarged view of the fulcrum portion corresponding to the second hinge shaft  110 . The vertex P of the inverse V-shaped portion  100   a  of the link member  100  is in contact with the underside of the frame  8   a , and the vertex P 1  of each V-shaped portion  100   b  ( 100   c ) is in contact with the upper surface of a rubber washer  112   a  interposed between the V-shaped portion  100   b  ( 100   c ) and the nut  112 . Accordingly, the link member  100  can be brought, at the vertexes P and P 1 , into slide-contact with the frame  8   a  and the rubber washer  112   a , thereby making it possible to swing the seat  8  in the direction shown by the arrow B. 
     With the above configuration, in the first position state in which the driver is not seated on the seat  8 , the seat  8  is biased upwardly by the coil spring  103 , so that the underside of the link member  100  is in contact with the overhang portion F of the dowel  8   b  and thereby the upward motion of the seat  8  in the direction shown by the arrow B is restricted. In such a state, since the underside of the dowel  8   b  is separated from the spindle  54   b  of the seating switch  54 , the seating switch  54  is turned off to detect the non-seating state. 
     When the driver is seated on the seat  8 , the seat  8  is downwardly turned against the repulsive force of the coil spring  103 , so that the underside of the dowel  8   b  depresses the spindle  54   b  of the seating switch  54 , with the result that the seating switch  54  is turned on to detect the seating state. 
     FIG. 15 is a view showing a second position state in which the seat  8  is downwardly turned around the fulcrum corresponding to the above-described second hinge shaft  110 , so that the underside of the dowel  8   b  depresses the spindle  54   b  of the seating switch  54 . 
     FIG. 16 is a view showing a state in which the seat  8  is opened for opening the luggage box  9 . Even in the state in which the seat  8  is opened, the seat  8  is biased by the coil spring  103  clockwise in FIG. 16 around the second hinge shaft  110  held between the bolts  111  and the nuts  112 , so that the link member  100  is pushed to the dowel  8   b  via the set plate  104 . Accordingly, even in the state in which the seat  8  is opened, the seat  8  is rigidly fixed on the link member  100  and thereby it is kept in the stable state. 
     FIG. 17 shows a variation of the second hinge shaft  110  allowing swing motion of the seat  8  in the direction shown by the arrow B. FIG. 17 is an enlarged sectional view of a variation of the second hinge shaft  110 . In this figure, the same reference numerals as those in FIGS.  12 ( a ) and  12 ( b ) designate the same or similar parts. In this variation, a structure in which the link member  100  is supported by the same shaft as the hinge shaft  102  is adopted in place of the fulcrum structure configured by the bolts  111 , nuts  112  and the upwardly and downwardly bent portions of the link member  100 . A second hinge shaft  110  is provided on the frame  8   a  of the seat  8  in parallel to the hinge shaft  102  for allowing the seat  8  to be swung around the second hinge shaft  110  in the direction shown by the arrow B. 
     FIG. 18 shows a variation of the arrangement structure of the coil spring  103 . FIG. 18 is an enlarged sectional view showing an essential portion of the variation of the arrangement structure of the coil spring  103 , and FIGS.  19 ( a ) and  19 ( b ) are sectional views showing a spring case for containing the coil spring. In these figures, the same reference numerals as those in FIGS.  12 ( a ) and  12 ( b ) designate the same or similar parts. In this variation, the coil spring  103  is disposed in the luggage box  9 . A spring case  106  is disposed in a space between a wall surface  9   a  of the luggage box  9  and the hinge shaft  102 . The spring case  106  is composed of a case main body  106   a  for containing the coil spring  103  and a lid  106   b . A flange  106   c  of the case main body  106   a  and the lid  106   b  are fixed to the luggage box  9  by way of a suitable fixing elements such as bolts and nuts. 
     A flanged plunger  107  is supported in a state in which one end thereof passes through a hole formed in the case main body  106   a  and the other end thereof passes through a hole formed in the lid  106   b . A flange  107   a  is formed on a portion, on the lid  106   b  side, of the plunger  107 . The falling off of the plunger  107  from the spring case  106  is restricted by the plunger  107   a . The coil spring  103  is interposed between the bottom of the case  106   a  and the flange  107   a . The plunger  107  is biased toward the lid  106   b  side by the repulsive force of the coil spring  103 . The spring case  106  is positioned such that the upper end of the plunger  107  faces to the underside of the dowel  8   b  formed on the frame  8   a  of the seat  8 . In other words, the seat  8  is pushed upwardly by the plunger  107  biased by the coil spring  103 . 
     The seating switch  54  is fixed on the side surface of the spring case  106 . The spindle  54   b  passes through holes formed in the flange  106   c  of the case main body  106   a  and the lid  106   b  and projects upwardly therefrom. The seating switch  54  is positioned such that the leading end of the spindle  54   b  is not brought into contact with the underside of the dowel  8   b  when the seat  8  is upwardly pushed to the uppermost position by the plunger  107 . 
     A state in which the dowel  8   b  is engaged with the link member  100  is shown in FIG.  19 ( b ) FIG.  19 ( b ) is a sectional view taken on line X—X of FIG.  19 ( a ) as shown in this figure, a projection T is formed at the outer edge of the hole  80   b  of the link member  100  and a hole H to be engaged with the projection T is formed in the front surface of the dowel  8   b . Since the link member  100  is thus engaged with the dowel  8   b  formed on the frame  8   a  of the seat  8 , the swing motion of the seat  8  in the direction shown by the arrow B is limited to a range in which the projection T is not brought into contact with the inner edge of the hole H. 
     When the driver is not seated on the seat  8 , the seat  8  is pushed upwardly by the plunger  107  biased by the coil spring  103 . In such a state, since the underside of the dowel  8   b  is separated from the spindle  54   b  of the seating switch  54 , the seating switch  54  is turned off to detect the non-seating state. 
     When the driver is seated on the seat  8 , the seat  8  downwardly depresses the plunger  107  against the repulsive force of the coil spring  103 , so that the underside of the dowel  8   b  depresses the spindle  54   b  of the seating switch  54 . As a result, the seating switch  54  is turned on to detect the seating state. 
     The fulcrum structure for allowing the swing motion of the seat  8  in the direction shown by the arrow B is configured by the bolts  110  and the nuts  112  is adopted in the variation shown in FIG. 18; however, the fulcrum structure may be configured by the second hinge shaft  110  described in the variation shown in FIG.  17 . 
     FIG. 20 shows another variation of the arrangement structure of the coil spring  103 . In this variation, the coil spring  103  is disposed in the frame  8   a  of the seat  8 . FIG. 20 is an enlarged sectional view showing a variation in which the coil spring  103  is disposed in the frame  8   a  of the seat  8 . In this figure, the same reference numerals as those in FIGS.  12 ( a ) and  12 ( b ) designate the same or similar parts. The spring case  106  for containing the plunger  107  biased by the coil spring  103  is disposed in a space formed by the frame  8   a  of the seat  8 , and is fixed to the frame  8   a . The spring case  106  is positioned such that the leading end of the plunger  107  is in contact with the upper surface of the link member  100 . The link member  100  is downwardly biased by the coil spring  103  via the plunger  107 . 
     Since the plunger  107  is pushed to the link member  100  by the coil spring  103 , the reaction force is applied to the plunger  107  and thereby a turning force in the direction shown by an arrow CW is applied to the seat  8 . The seating switch  54 , which is fixed on the side surface of the spring case  106 , is positioned such that the downwardly projecting spindle  54   b  faces to the upper surface of the link member  100 . 
     When the driver is not seated on the seat  8 , the plunger  107  biased by the coil spring  103  is pushed to the link member  100 , and the seat  8  is pushed upwardly by the reaction force applied to the plunger  107 . In such a state, the seating switch  54  is positioned such that the upper surface of the link member  100  is separated from the spindle  54   b  of the seating switch  54 , so that the seating switch  54  is turned off to detect the non-seating state. 
     When the driver is seated on the seat  8 , the seat  8  is downwardly pushed against the repulsive force of the coil spring  103 , and the plunger  107  is retreated and the seat  8  is turned in the direction shown by an arrow CCW relative to the link member  100 . As the plunger  107  is retreated, the spindle  54   b  of the seating switch  54  is pushed upwardly by the upper surface of the link member  100 . As a result, the seating switch  54  is turned on to detect the seating state. 
     In FIG. 20, a profile  100   a  of the link member  100  shown by a two-dot chain line designates the position of the link member  100  in the seating state. That is to say, in the non-seating state, the reaction force of the biased coil spring  103  is applied to the seat  8  such that the seat  8  is turned in the direction shown by the arrow CCW around the fulcrum formed by the bolts  111 , the nuts  112  and the link member  100 . However, since the rear portion of the seat  8  is locked, the turning of the seat  8  is restricted. The result is that the fulcrum is kept in the floating state by the reaction force of the turning motion of the seat  8 . The fulcrum thus floated is descended along with the downward movement of the seat  8  caused when the driver is seated on the seat  8 , and thereby the link member  100  is fixed to the position shown by the profile  100   a.    
     The bearing for supporting the hinge shaft  102  is formed integrally with the luggage box  9  in the variation shown in FIG. 20; however, it is not necessarily integrated with the luggage box  9 . For example, a bearing separated from the luggage box  9  may be fixed to the luggage box  9  with a bolt or the like. 
     With the above-described structure associated with the front portion of the seat and the seating switch, since the seat  8  is supported by the hinge shaft  102  passing through the circular holes provided in both the side surfaces of the luggage box  9 , the seating comfort is stabilized unlike the conventional structure in which the seat  8  is supported by a hinge shaft passing through a slotted hole. Further, since the front portion of the seat  8  is floated upwardly by the link, that is, the link member  100  and the coil spring  103 , the vertical stroke of the seat  8  upon seating or non-seating of the driver can be made larger, so that the operational position of the seating switch  54  can be easily set. 
     FIG. 6 is a block diagram showing the entire configuration of a system of controlling the starting/stopping of the internal combustion engine  200  including the starter/generator  250  for directly rotating the crank shaft  201 . 
     An engine stopping/starting system in this embodiment includes an operational mode in which idling is restricted and another operational mode in which idling is permitted. To be more specific, the system includes an engine-stopping/vehicle-moving mode (idling restricting mode), a starting mode (idling permitting mode), and an idle switch mode. 
     In the engine stopping/vehicle-moving mode, when the movement of the vehicle is stopped, the engine is automatically stopped, and when the accelerator is operated in the stopped state, the engine is automatically restarted to move the vehicle. 
     In the starting mode, idling is temporarily permitted after the initial starting of the engine in order to perform, for example, a warming operation upon starting of the engine. 
     In the idle switch mode, idling is usually permitted in accordance with the intention of the driver by turning on an idle switch  53  to be described later. 
     The starter/generator  250  is coaxially connected to the crank shaft  201  of the engine  200 . The starter/generator  250  is composed of a starter motor  71  and an AC generator (ACG)  72 . The power generated by the ACG  72  is charged in a battery  68  via a regulator rectifier  67 . The regulator rectifier  67  controls the voltage outputted from the starter/generator  250  at a value ranging from 12 V to 14.5 V. The battery  68  is adapted to supply, when a starter relay  62  is conducted, a drive current to the starter motor  71 , and to supply a load current to various kinds of general electrical equipment  74 , a main control unit  60  and the like via a main switch  73 . 
     The main control unit  60  is connected to a Ne sensor  51 , a throttle switch  52 , an idle switch  53 , a seating switch  54 , a vehicular speed sensor  55 , a standby indicator  56 , a throttle sensor  57 , a starter switch  58 , a stop switch  59 , and a battery indicator  76 . The Ne sensor  51  detects an engine rotation rate Ne. The throttle switch  52  outputs a signal of an “H” level if a throttle opening O is not in the full-close state. The idle switch  53  manually permits or limits idling of the engine  200 . The seating switch  54  closes the contact when the driver is seated on the seat and outputs a signal of the “H” level. The vehicular speed sensor  55  detects the vehicular speed. The stand-by indicator  56  flashes upon vehicle stop under the engine stopping/vehicle-moving mode to be described later. The throttle sensor  57  detects the throttle opening O. The starter switch  58  drives the starter motor  71  of the starter/generator  250  to start the engine  200 . The stop switch  59  outputs a signal of the “H” level in response to braking operation. The battery indicator  76  lights up when the voltage of the battery  68  is reduced to a predetermined value (for example, 10 V) or less and warns the driver of the shortage of the charged amount of power in the battery  68 . It should be noted that as described above, the throttle switch  52  may be omitted by making the throttle sensor  57  serve the function of the throttle switch  52 . 
     The main control unit  60  is also connected to an ignition controller (including an ignition coil)  61 , a control terminal of the starter relay  62 , a control terminal of a head lamp relay  63 , a control terminal of a by-starter relay  64 , and a buzzer  75 . The ignition controller  61  ignites an ignition plug  206  in synchronization with rotation of the crank shaft  201 . The starter relay  62  supplies a power to the starter motor  71 . The head lamp relay  63  supplies a power to the head lamp  69 . The by-starter relay  64  supplies a power to a by-starter  65  mounted to a carburetor  66 . The buzzer  75  generates buzzer sounds under a specific condition for giving a warning to the driver. 
     The control of the supply of a power to the head lamp  69  is not limited to turn-on/off of the head lamp relay  63 . As shown in FIG. 21, a so called chopping control may be adopted in which switching elements  63   a  such as FETs are used in place of the head lamp relay  63  wherein the switching elements  63   a  are interrupted with a specific cycle and a specific duty ratio in place of cutoff of the power supply to thereby substantially reduce the voltage applied to the head lamp  69 . 
     FIG. 7 is a block diagram showing the function of the configuration of the main control unit  60 , and FIG. 8 is a block diagram continued from FIG.  7 . In these figures, the same reference numerals as those described above designate the same or similar parts. FIG. 9 shows a list of control contents of a starter relay control unit  400 , a by-starter control unit  900 , a stand-by indicator control unit  600 , an ignition control unit  700 , an operation switching unit  300 , a warning buzzer control unit  800 , and a charging control unit  500 . 
     The operation switching unit  300  switches, depending on the state of the idling switch  53 , the state of the vehicle and the like, the operational mode of the engine starting/stopping control unit into either of the starting mode, in which idling is permitted under the specific condition, the engine-starting/vehicle-moving mode, in which the idling is restricted, and the idle switch (SW) mode, in which idling is usually permitted. The operation switching unit  300  further switches the engine-stopping/vehicle-moving mode into either a first operational pattern (hereinafter, referred to as a “first pattern”) in which idling is prohibited, or a second operational pattern (hereinafter, referred to as “second pattern”) in which idling is permitted under a specific condition. The second pattern of the engine stopping/vehicle-moving mode is desirable as a battery exhaustion preventive mode for when the engine is stopped for a long period of time and the head lamp is on. 
     In the operation switching unit  300 , a signal indicating the state of the idle switch  53  is inputted in an operation switching signal output unit  301 . If the operational state is in the OFF state (idling restricting state), the signal indicating the state of the idle switch  53  exhibits an “L” level. If the operational state is in the ON state (idling permitting state), the signal indicating the state of the idle switch  53  exhibits the “H” level. A vehicular speed continuously deciding unit  303  includes a timer  303   a . If the vehicular speed sensor  55  detects a predetermined vehicular speed or more for a predetermined time or more, the vehicular speed continuously deciding unit  303  outputs a signal of the “H” level. 
     The operation switching signal output unit  301  outputs signals S 301   a , S 301   b  and S 301   c  for switching the operational mode and the operational pattern of the main control unit  60 , in response to the signals outputted from the idle switch  53  and the vehicular speed continuously deciding unit  303 , and further to an ignition off signal S 11021  Of the “H” level if the ignition off state of the engine is continued for a specific time (3 minutes in this embodiment) or more. 
     FIG. 10 is a diagram showing conditions for switching the operational mode and the operational pattern of the operation switching signal output unit  301 . 
     In the operation switching signal output unit  301 , if a condition (1) is established in which the main switch  73  is turned on and thereby the control unit  60  is reset or the idle switch  53  is turned off, the starting mode is raised by the operational mode switching unit  301   a . At this time, the operational mode switching unit  301  a outputs the operational mode signal S 301 , of the L level. 
     If in the starting mode, a condition (2) is established in which the predetermined vehicular speed or more is continued for the predetermined time or more, the operational mode is changed from the starting mode into the engine-stopping/vehicle-moving mode by the operational mode switching unit  301   a . At this time, the L level of the operational mode signal S 301 , outputted from the operational mode switching unit  301   a  is changed into the H level. 
     As described above, the engine-stopping/vehicle moving mode includes the first pattern in which idling is prohibited and the second pattern in which idling is conditionally permitted under the specific condition, and directly after the starting mode is shifted into the engine-stopping/vehicle-moving mode as described above, the first pattern in which idling is prohibited is raised by an operational pattern switching unit  301   b . At this time, the operational pattern switching unit  301   b  outputs the operational pattern signal S 311   b  of the L level. 
     If in the first pattern a condition (3) is established in which an ignition off state continuously deciding unit  802  (to be described with reference to FIG. 7) decides that the ignition off state is continued for 3 minutes or more, the operational pattern of the engine stopping/vehicle-moving mode is changed from the first pattern into the second pattern by the operational pattern switching unit  301   b . At this time, the L 1  level of the operational pattern signal S 301   b  outputted from the operational pattern switching unit  301   b  is changed into the H level. 
     If the above condition (2) is established in the second pattern, the operational pattern is changed from the second pattern into the first pattern by the operational pattern switching unit  301   b . At this time, the H level of the operational pattern signal S 301   b  outputted from the operational pattern switching unit  301   b  is changed into the L level. 
     Research indicates that a driver waits from about 30 seconds to about 2 minutes at an intersection. The vehicle can be stopped for a time over the above waiting time can be caused by restriction to one-way traffic due to highway work, traffic jams, etc. Accordingly, in the operational mode/operational pattern control in this embodiment, if the engine is stopped for a long period of time (3 minutes or more in this embodiment) while the head lamp is left on during operation under the engine-stopping/vehicle moving mode, the operational pattern is changed from the first pattern into the second pattern, in which idling is permitted. Consequently, as will be described in detail later, if the starter switch  58  is turned on by the driver, the engine can be restarted, to enable the stoppage of the vehicle in the idling state, thereby preventing the battery exhaustion due to extended lighting of the head lamp  69 . 
     If a condition (6) is established in which the main switch in the OFF state is turned on and the idle switch is turned on, the idling switch mode is raised by an idle switch mode raising unit  301 C. At this time, the L level of the operational mode signal S 301   c  outputted from the idle switch mode raising unit  301 C is changed into the H level. It should be noted that in the engine stopping/vehicle-moving mode, if the idle switch  53  is turned on and the condition (4) is established, the idle switch mode is raised irrespective of the first pattern and the second pattern. 
     If in the idle switch mode the condition (5) is established in which the idle switch  53  is turned off, the starting mode is raised by the operational mode switching unit  301   a . At this time, the operational mode switching unit  301   a  outputs the operational mode signal S 301   a  Of the L level. 
     Referring again to FIG. 7, a signal outputted from the Ne sensor  51  is inputted into a Ne deciding unit  306  of the operational switching unit  300 . If the Ne deciding unit  306  decides that the engine rotation rate is more than the predetermined value, it outputs a signal of the H level to a head lamp control unit  305 . If the Ne deciding unit  306  decides once that the engine rotation rate is more than the predetermined value, it continuously outputs a signal of the H level until the main switch  73  is turned off When the head lamp relay  63  receives the signal of the H level, it allows the head lamp  69  to light up. 
     The head lamp control unit  305  outputs a control signal of the H level or the L level to the control terminal of the head lamp relay  63  on the basis of the operational mode (pattern) signals S 301   a , S 301   b  and S 301   c , the signal outputted from the Ne deciding unit  306 , and a signal outputted from a running deciding unit  701 . 
     If the switching elements  63   a  (see FIG. 21) are adopted in place of the head lamp relay  63 , the head lamp control device  305  outputs a pulse signal with a specific cycle and a specific duty ratio for chopping control of the supply of a power to the head lamp  69 , in place of the output of the control signal of the L level. 
     In this embodiment, as shown in FIG. 9, the ON signal is usually outputted in any operational mode other than the starting mode, and in the starting mode, the ON signal is outputted if the specific engine rotation rate (1500 rpm in this embodiment) is detected by the Ne deciding unit  306  or it is decided by the running deciding unit  701  that the vehicular speed is more than 0 km. 
     If the switching elements  63   a  (see FIG. 21) are adopted in place of the head lamp relay  63 , as shown in FIG. 22, in the first pattern of the engine stopping/vehicle-moving mode, the discharge of the battery can be suppressed at minimum by chopping control of the opening/closing of the switching elements  63   a  in accordance with the ignition control (to be described in detail later). 
     To be more specific, when the ignition control is interrupted (turned off) in response to vehicle stop and the engine is automatically stopped, the head lamp control device  305  performs chopping control of the switching elements  63   a  on the basis of a pulse signal with a specific cycle and a specific duty ratio so that the voltage applied to the head lamp  69  is substantially reduced from a voltage (for example, 13.1 V) in the usual ON state to a specific voltage (for example, 8.6 V) in the dimming state, to thereby dim the head lamp  69 . After that, when the ignition control is restarted in response to the vehicle movement operation and the engine is restarted, the head lamp control device  305  outputs a DC signal of the H level to the switching elements  63   a.    
     In this way, by dimming the head lamp  69  upon automatic stoppage of the engine, the discharge of the battery can be suppressed without turning the head lamp off. As a result, the amount of charging from the generator to the battery upon the subsequent vehicle movement operation can be reduced, to lower the electrical load of the generator, thereby improving the accelerating performance upon vehicle movement. 
     The ignition control unit  700  permits or prohibits the ignition operation by the ignition controller  61  under a specific condition for each operational mode or each operational pattern. In the ignition control unit  700 , a detection signal from the vehicular speed sensor  55  is inputted in the running deciding unit  701 . The running deciding unit  701  decides on the basis of the detection signal whether or not the vehicle is in the running state. If the running deciding unit  701  decides that the vehicle is in the running state, it outputs a signal of the H level. 
     An OR circuit  702  outputs a logic sum of the signal outputted from the running deciding unit  701  and the signal indicating the state of the throttle switch  52 . An OR circuit  704  outputs a logic sum of a reversed signal of the operational mode signal S 301   a , the operational pattern signal S 301   b , and the operational mode signal S 301 . An OR circuit  703  outputs a logic sum of signals outputted from the OR circuits  702  and  704  to the ignition controller  61 . If the signal inputted in the ignition controller  61  is at the H level, the ignition controller  61  executes the ignition operation for each timing, and if at the L level, the ignition controller  61  interrupts the ignition operation. 
     With this ignition control, as shown in FIG. 9, if the operational mode is either of the starting mode, the second pattern of the engine-stopping/vehicle-moving mode or the idle switch mode, the signal outputted from the OR circuit  704  exhibits the H level, so that the signal of the H level is usually outputted from the OR circuit  703 . Accordingly, in the starting mode, the second pattern of the engine-stopping/vehicle-moving model or the idle switch mode, the ignition controller  61  is usually operated. 
     On the contrary, in the first pattern of the engine-stopping/vehicle-moving mode, since the signal outputted from the OR circuit  704  exhibits the L level, the ignition operation is executed under the condition that the running deciding unit  701  decides that the vehicle is in the running state, or the throttle is opened and the output from the OR circuit  702  exhibits the H level. In other words, if the vehicle is in the stopped state or the throttle is closed, the ignition operation is interrupted. 
     The warning buzzer control unit  800  shown in FIG. 7 generates a warning, for example, a buzzer for giving a necessary caution to the driver in accordance with the running state of the vehicle and the seating state of the driver for each operational mode or operational pattern. 
     A non-seating state continuation deciding unit  801  receives a signal indicating the state of the seating switch  54 . The non-seating state continuation deciding unit  801  includes a timer  8012  for counting a non-seating time of the driver. If the timer  8012  times out, the non-seating state continuation deciding unit  801  outputs a non-seating state continuation signal S 8012  Of the H level. The timer  8012  in this embodiment is previously set such that it times out for 1 sec. 
     An ignition off state continuation deciding unit  802  includes a timer  8021  for counting an ignition off time of the engine. If the ignition off state continuation deciding unit  802  detects the ignition off state, it immediately outputs an ignition-off signal S 8021  of the H level and starts the timer  8021 . If the timer  8021  times out, the ignition off state continuation deciding unit  802  outputs an ignition off continuation signal S 8021  Of the H level. In this embodiment, the timer  8021  is set such that it times out for 3 min. 
     A buzzer control unit  805  determines the ON/OFF state of the buzzer  75  on the basis of the operational mode (pattern) signals S 301   a , S 301   b  and S 301 , the non-seating continuation signal S 8012 , the ignition off state continuation signal S 8021 , the ignition off signal S 1023 , the signal outputted from the running deciding unit  701  and the signal outputted from the throttle switch  52 . If the buzzer control unit  805  decides that the buzzer  75  is to be turned on, it outputs a signal of the H level to a buzzer drive unit  814 . 
     Referring to FIG. 9, the operation of a buzzer control unit  805  will be described. In the starting mode, the buzzer control unit  805  usually turns off the buzzer  75 . In the first pattern of the engine stopping/vehicle-moving mode, if non-seating in the ignition off state is continued for the time (1 second in this embodiment) required for time-out of the timer  8012  or more or the ignition off state is continued for the time (3 minutes in this embodiment) required for time-out of the timer  8021  or more, the buzzer control unit  805  turns on the buzzer  75 . 
     In the second pattern of the engine stopping/vehicle-moving mode, if the ignition is in the OFF state, the throttle switch  52  is turned off and the vehicular speed decided by the running deciding unit  701  is 0 km, the buzzer control unit  805  turns on the buzzer  75 . In the idle switch mode, if the ignition is in the OFF state and the non-seating state is continued for 1 second or more, the buzzer control unit  805  turns on the buzzer  75 . If the signal outputted from the buzzer control unit  805  exhibits the H level, a buzzer control unit  814  outputs, to the buzzer  75 , a buzzer drive signal for repeatedly actuating the buzzer  75  with the ON time of 0.2 second and the OFF time of 1.5 sec. 
     In this way, according to this embodiment, during operation under the engine-stopping/vehicle-moving mode, if the vehicle must be stopped (the engine must be stopped) for a long period of time (3 min or more in this embodiment) with the head lamp left as turned on due to restriction for one-way traffic for highway work or the like, the operational pattern of the engine stopping/vehicle-moving mode is changed from the first pattern into the second pattern, and simultaneously a buzzer is generated for informing the driver of permission for idling. Accordingly, only by turning on the starter switch  58  in response to the buzzer, it is possible to prevent battery exhaustion due to continuation of switch-on of the head lamp  69  for a long period of time. 
     In the charging control unit  500  shown in FIG. 7, an acceleration detecting unit  502  compares a signal outputted from the throttle sensor  57  with the opening/closing timing of the throttle switch  52 . If the vehicular speed is more than 0 km and a time required for the throttle to be opened from the throttle full-close state to the throttle full-open is within 0.3 seconds for example, the acceleration detecting unit  502  decides such a state as the acceleration and it outputs one shot of acceleration detecting pulse. 
     If the throttle switch  52  is turned on under a condition with the vehicular speed of 0 km and a specific engine rotation rate (2500 rpm in this embodiment) or less, a vehicle moving operation detecting unit  503  decides such a state as the vehicle moving operation and it outputs one shot of vehicle moving operation detecting pulse. When a charging limiting unit  504  receives the above acceleration detecting pulse signal, it starts a 6 second timer  504   a . The charging limiting unit  504  controls the regulator rectifier  67  to reduce the voltage charged in the battery from the usual value, 14.5 V to 12.0 V until the 6 second timer  504   a  times out. 
     With this charging control, upon rapid acceleration in which the driver rapidly opens the throttle or upon vehicle movement from the stopped state, the charging voltage is reduced, so that the electrical load of the starter/generator  250  is temporarily reduced. This makes it possible to reduce the mechanical load of the engine  200  caused by the starter/generator  250  and hence to improve the accelerating performance. 
     As described with reference to FIG. 21, if there is adopted the configuration in which upon automatic stoppage of the engine the switching elements  63   a  are chopping-controlled to dim the head lamp  69  thereby suppressing the discharge of the battery at minimum, it is possible to further reduce the load of the starter/generator  250 , and hence to further improve the accelerating performance. 
     As shown in FIG. 9, if the  6  second time  504   a  times out, the engine rotation rate exceeds a specific value (7000 rpm in this embodiment), or the throttle opening is reduced, the charging limiting unit  504  stops the charging control and returns the charging voltage to the usual value, 14.5 V. 
     Referring to FIG. 8, the starter relay control unit  400  manually or automatically starts the starter relay  62  under a specific condition in accordance with each operational mode or operational pattern. In the starter relay control unit  400 , the detection signal from the Ne sensor  51  is supplied to an idling rotation rate or less deciding unit  401 . If the engine rotation rate is a specific idling rotation rate (for example, 800 rpm ) or less, the idling rotation rate or less deciding unit  401  outputs a signal of the H level. 
     An AND circuit  402  outputs a logic product of the signal outputted from the deciding unit  401 , the signal indicating the state of the stop switch  59 , and the signal indicating the state of the starter switch  58 . An AND circuit  404  outputs a logic product of the signal outputted from the idling rotation rate or less deciding unit  401 , the signal indicating the state of the throttle switch  52  and the signal indicating the state of the seating switch  54 . The OR circuit  408  outputs a logic sum of the signals outputted from the AND circuits  402  and  404 . 
     An OR circuit  409  outputs a logic sum of the reversed signals of the operational mode signals S 301 , and S 301   a . An AND circuit  403  outputs a logic product of the signal outputted from the AND circuit  402  and the signal outputted from the OR circuit  409 . An AND circuit  405  outputs a logic product of the signal outputted from the AND circuit  404 , the operational mode signal S 301   a , and the  63  reversed signal of the operational pattern signal S 311   b . An AND circuit  407  outputs a logic product of the operational mode signal S 30 , a , the operational pattern signal S 301   b , and the signal outputted from the OR circuit  408 . An OR circuit  406  outputs a logic sum of the signals outputted from the AND circuits  403 ,  405  and  407  to the starter relay  62 . 
     With this starter relay control, in the starting mode and the idle switch mode, since the signal outputted from the OR circuit  409  exhibits the H level, the AND circuit  403  becomes the enable state. Accordingly, when the engine rotation rate is the idling rotation rate or less and the stop switch  59  is in the ON state (during braking operation), the starter switch  58  is turned on by the driver and thereby the signal outputted from the AND circuit  402  exhibits the H level, then the starter relay  62  is conducted to start the starter motor  71 . 
     In the first pattern of the engine stopping/vehicle-moving mode, the AND circuit  405  becomes the enable state. Accordingly, if the throttle is opened, the engine rotation rate is the idling rotation rate or less and the seating switch  54  is in the ON state (during seating of the driver), then the signal outputted from the AND circuit  404  exhibits the H level, so that the starter relay  62  is conducted to start the starter motor  71 . 
     In the second pattern of the engine stopping/vehicle-moving mode, the AND circuit  407  becomes the enable state. Accordingly, if either the AND circuit  402  or the AND circuit  404  exhibits the H level, the starter relay  62  is conducted to start the starter motor  71 . 
     In the by-starter control unit  900 , the signal outputted from the Ne sensor  51  is inputted in an Ne deciding unit  901 . If the engine rotation rate is a specific value or more, the Ne deciding unit  901  outputs a signal of the H level to close the by-starter relay  64 . With this configuration, even in any operational mode, the fuel can be made rich when the engine rotation rate is the specific value or more. 
     In the indicator control unit  600 , the signal outputted from the Ne sensor  51  is inputted in an Ne deciding unit  601 . If the engine rotation rate is the specific value or less, the Ne deciding unit  601  outputs a signal of the H level. An AND circuit  602  outputs a logic product of the signal indicating the state of the seating switch  54  and the signal outputted from the Ne deciding unit  601 . An AND circuit  603  outputs a logic product of the signal outputted from the AND circuit  602 , and the reversed signals of the operational mode signal S 301   a  and the operational pattern signal S 301   b  to the standby indicator  56 . 
     If the signal inputted in the stand-by indicator  56  exhibits the L level, the stand-by indicator  56  is turned off, and if the inputted signal exhibits the H level, the stand-by indicator  56  flashes. 
     To be more specific, since the stand-by indicator  56  flashes during vehicle stop in the “engine stopping/vehicle-moving mode”, the driver can recognize that insofar as the stand-by indicator  56  flashes, the vehicle can be immediately moved by actuating the accelerator even if the engine is stopped. 
     FIG. 11 is a block diagram showing the entire configuration of the starting/stopping control system according to another embodiment of the present invention. 
     In this figure, the same reference numerals as those in FIG. 6 designate the same or similar parts. In this embodiment, the power generated by the AC generator  72  is charged in two batteries  68 A and  68 B via the regulator rectifier  67 . The battery  68 A is specialized for starting the engine. When the starter relay  62  is conducted, the battery  68 A supplies a drive current to the starter motor  71 . The battery  68 B is used for supplying a load current to various kinds of electrical equipment  74 , the main control unit  60  and the like via the main switch  73 . 
     In this way, according to this embodiment, since the battery  68 A specialized for starting the engine is very small in power consumption and is usually kept in full-charged state, it usually enables desirable starting of the engine irrespective of the charged amount of the battery  68 B. 
     The present invention exhibits the following effects: 
     When the vehicle moving operation is detected, the charging from the generator to the battery is limited to reduce the electrical load of the generator. Accordingly, since the torque required for the engine to drive the generator is reduced, the accelerating performance is improved. Also since the charging from the generator to the battery upon vehicle movement from vehicle stop is not interrupted but only limited, the light from the head lamp becomes dark upon vehicle movement. 
     The accelerating performance can be improved not only upon vehicle movement from vehicle stop, but also acceleration during running. 
     The charging limitation upon vehicle movement after vehicle stop or upon acceleration can be simply performed by control of a voltage of the regulator. 
     When the ignition control of the engine is interrupted upon vehicle stop and the engine is automatically stopped, the voltage applied to the head lamp is substantially reduced. The amount of charging from the generator to the battery can therefore be reduced. As a result, the electrical load of the generator is reduced, which improves accelerating performance upon vehicle movement. Further, by using charging control for limiting a charging voltage upon acceleration in combination with this invention, since the torque required for the engine to drive the generator can be further reduced upon vehicle movement after restarting of the engine, the accelerating performance can be further improved. 
     The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.