Abstract:
A handlebar steered vehicle includes an operation lever provided on the steering handlebar, an operation detection switch for detecting an operation of the operation lever, and a starting circuit including a starting switch for connecting a battery with a starter motor, the operation detection switch and the starting switch being connected in series with the battery, such that the battery and the starter motor are connected to each other when the operation detection switch and the starting switch are tuned on. Further, a control unit drives a relay to connect the battery to a vehicle load, when an engine speed reaches or exceeds a predetermined value.

Description:
FIELD OF THE INVENTION 
   The present invention relates generally to a vehicle and, more particularly, to an electricity supply device or starting circuit for a vehicle which is steered by a handlebar. 
   RELATED ART 
   A vehicle, which includes a generator and a battery and which turns on a headlamp by supplying the headlamp with electricity generated by the generator and/or stored in the battery, has found practical applications. 
   A principal switch, to which a name, such as a main switch, a combination switch, an ignition switch, or the like, is given, is generally interposed in an electric circuit for achieving the purpose noted above (see, for example, Japanese Patent Laid-open No. Hei 9-290684 (JP &#39;684). 
   Referring to  FIG. 1  of JP &#39;684, an ignition switch with a reference numeral of S corresponds to the principal switch. Turning on (or closing) the ignition switch S puts an electric circuit into an active state. As described in the foregoing, an ordinary vehicle is provided with the principal switch and it is prerequisite that this principal switch be turned on before the vehicle shifts from a ready state to a running-enabled state. 
   There is a demand for a vehicle that dispenses with the principal switch for reasons of applications in racing or for a reduction in the number of switch components. 
   It is, however, readily impossible to dispense with the ignition switch S disclosed in JP &#39;684, since the switch S connects and disconnects a circuit between the battery and the headlamp. 
   To state it another way, to dispense with a principal switch, such as the ignition switch S, it becomes necessary to configure a special electric circuit. 
   SUMMARY OF THE INVENTION 
   An object of the present invention is to provide an electricity supply device particularly suitable for a racing vehicle that is not provided with the principal switch, ensures good starting, and that does not allow the battery thereof to run down by devising the electronic circuit. 
   In a first aspect of the present invention, a handlebar steered vehicle includes an operation lever, an operation detection switch, and a starting circuit. The operation lever is provided on a steering handlebar. The operation detection switch detects an operation of the operation lever. The starting circuit includes a starting switch for connecting a battery with a starter motor. 
   The vehicle is characterized by the following. Specifically, only the operation detection switch and the starting switch are connected in series with the battery. The battery and the starter motor are connected when the operation detection switch and the starting switch are turned on (or closed). A control unit is also provided for driving a relay. The relay connects the battery to a vehicle load when an engine speed reaches or exceeds a predetermined value. 
   In a second aspect of the present invention, the vehicle includes a headlight and a generator for generating electricity using an output from an engine. The vehicle is characterized in that the headlight is directly connected to the generator. 
   In a third aspect of the present invention, the control unit is an ignition control unit for the vehicle. 
   In a fourth aspect of the present invention, the operation lever is disposed on a side of the steering handlebar opposite to a side on which the starting switch is provided. 
   According to the first aspect of the present invention, the starter motor is turned to start the engine when the following two conditions are met: specifically, the operation lever is operated and the starting switch is pressed. This provides a vehicle capable of starting the engine without being provided with the principal switch typically represented by the ignition switch. There is no likelihood of erroneous operation, since the engine cannot be started only with the starting switch. 
   In addition, a general load is connected to a main circuit including the battery by way of a relay that turns on when the engine speed reaches or exceeds a predetermined value. This allows a supply of electricity flowing to the general load to be shut down when the engine is not running. As a result, a rundown battery can be avoided. 
   According to the second aspect of the present invention, the headlight is directly connected to the generator. This means that the generator can shoulder the burden of supplying electricity to the headlight. As a result, the load on the battery mounted on the vehicle can be reduced, thus extending the life of the battery. 
   According to the third aspect of the present invention, the control unit is the ignition control unit for the vehicle. This eliminates the need for providing a separate control unit, thus avoiding an increased cost. 
   According to the fourth aspect of the present invention, the operation lever is disposed on a side of the steering handlebar opposite to the side on which the starting switch is provided. This results in the operability of the operation lever and of the starting switch being enhanced. 
   The best mode for carrying out the present invention will be described with reference to the accompanying drawings. The drawings should be viewed in the direction of reference numerals. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A preferred embodiment of the present invention will be described with reference to the accompanying drawings, wherein: 
       FIG. 1  is a side elevational view showing a vehicle according to the present invention; 
       FIG. 2  is a view in the direction of arrow  2  of  FIG. 1 ; 
       FIG. 3  is a plan view showing a front portion of the vehicle according to the present invention; 
       FIG. 4  is a view showing the right throttle grip as viewed from the front; 
       FIG. 5  is a perspective view illustrating procedures for mounting a switch box according to a preferred embodiment of the present invention; 
       FIG. 6  is an electric circuit diagram applied to the vehicle according to the present invention; 
       FIG. 7  is an operational flowchart for starting the vehicle according to the present invention; and 
       FIG. 8  is an operational flowchart for starting the vehicle through kick starting. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  is a side elevational view showing a vehicle according to the present invention. A vehicle  10  may typically be a motorcycle, or a racing vehicle running on an unpaved road or the like of a closed course. The vehicle  10  is typically configured as follows. Specifically, a head pipe  12  is provided at a front end of a vehicle body frame  11 . A front fork  13  is provided for the head pipe  12 . A front wheel  14  is rotatably mounted on a lower portion of the front fork  13 . A steering handlebar  15  is attached to an upper end of the front fork  13 . A headlight  16  is provided on the head pipe  12 . An engine  17  is mounted at a center of the vehicle body frame  11 . A swing arm  18  is extended from a rear portion of the vehicle body frame  11 . A rear wheel  19  is rotatably mounted at a rear portion of the swing arm  18 . The rear wheel  19  is driven by the engine  17  by means of a chain  21  and a sprocket  22 . The vehicle  10  is mounted only with minimum essential auxiliaries, including the headlight and a tail light. 
   The vehicle  10  includes a kick start pedal not shown. The engine can be started also by depressing the kick start pedal. 
   Reference numeral  23  represents a brake caliper. Reference numeral  24  represents a front fender. Reference numeral  25  represents a cooling fan motor. Reference numeral  26  represents a seat. Reference numeral  27  represents a rear side cover. Reference numeral  28  represents a rear fender. Reference numeral  29  represents a tail light. 
     FIG. 2  is a view in the direction of arrow  2  of  FIG. 1 .  FIG. 2  shows that the tail light  29  is composed as follows. Specifically, a step portion  31  is provided on a rear portion of the rear fender  28 . A crosswise slit is made in a vertical wall portion of the step portion  31 . A tail light unit  32  with a built-in LED (Light Emitting Diode) is then fitted into this crosswise slit. 
     FIG. 3  is a plan view showing a front portion of the vehicle according to the present invention.  FIG. 3  shows different parts (described below) mounted on the steering handlebar  15  of a bar handle shape. Specifically, an engine stop switch  35 , and a clutch lever  36 , and a hot start lever  37  as operation levers are mounted in areas near left grip  34 . A front brake lever  39  and a starting switch  41  are mounted in areas near right throttle grip  38 . Reference numeral  42  represents a fuel tank. Reference numeral  43  represents a fuel filler cap. Reference numeral  44  represents an air vent pipe. 
   A feature of the present invention includes mounting a switch box  45 , including the starting switch  41 , according to the preferred embodiment of the present invention. An explanation of the feature is set forth below. 
     FIG. 4  is a view showing the right throttle grip as viewed from the front. A throttle cable  46  for transmitting an amount of rotation of the throttle grip  38  extends from a throttle housing  47 . Specifically, the throttle housing  47  has a built-in mechanism for translating the amount of rotation to a corresponding amount of linear movement. The throttle housing  47  is rigidly mounted to the steering handlebar  15 . 
   A rectangular protrusion  48  is provided in a protruding condition rightwardly in  FIG. 4  from a front portion of the throttle housing  47 . Reference numeral  49  represents a reinforcement rib for reinforcing the protrusion  48 . The reinforcement rib  49  substantially enhances a bending stiffness of the protrusion  48  in a front-to-back direction of  FIG. 4 . 
   Two tabs  51 ,  51  are extended leftwardly in  FIG. 4  from a front portion of the switch box  45 . A rectangular recess  52  is then formed between these two tabs  51 ,  51 . Dimensions of the recess  52  correspond to the protrusion  48 . 
   The switch box  45  is mounted to the steering handlebar  15  such that the protrusion  48  fits into the recess  52 . Detailed procedures for mounting the switch box  45  to the steering handlebar  15  will be described below. 
     FIG. 5  is a view for explaining procedures for mounting the switch box according to the preferred embodiment of the present invention. The switch box  45  includes: a box front portion half body  53  having the recess  52 ; a box rear portion half body  54  having the starting switch (identified by reference numeral  41  in  FIG. 3 ); and screws  55 ,  55  for joining together half bodies  53  and  54 . 
   The box front portion half body  53  is first disposed such that the recess  52  fits into the protrusion  48  of the throttle housing  47 . Then, the box front portion half body  53  is mated with the box rear portion half body  54 . The screws  55 ,  55  are then tightened to join the box rear portion half body  54  with the box front portion half body  53 . At the same time, half bodies  53 ,  54  are supported on the steering handlebar  15  by sandwiching handlebar  15  between the box front portion half body  53  and the box rear portion half body  54 . 
   When a rider presses the starting switch (identified by the reference numeral  41  in  FIG. 3 ), a moment acts on the switch box  45  such that a force acts to rotate the switch box  45  about the steering handlebar  15 . According to the embodiment of the present invention, the recess  52  in the switch box  45  fits over the protrusion  48  of the throttle housing  47 . This effectively inhibits the switch box  45  from rotating. 
   To mount the switch box  45  having a two-separable-part structure on the steering handlebar  15  made of steel pipe, it is common practice to inhibit the switch box  45  from turning by making a hole in the steering handlebar  15  made of steel pipe and fitting the protrusion provided on the switch box  45  into the hole. This requires an additional process of making a hole in the steering handlebar  15 , resulting in an increased cost. Moreover, there is a trace of the hole left in the steering handlebar  15 . 
   In this respect, in accordance with the embodiment of the present invention, the switch box  45  is engaged with the throttle housing  47  for achieving locking of the switch box  45 . This eliminates the need for making a hole, and thus no hole is made in the steering handlebar  15 . 
     FIG. 6  is an electric circuit diagram applied to the vehicle according to the present invention. The electric circuit is characterized in that a general load circuit  71  is connected to a main circuit  60  via relay  70 . The main circuit  60  includes a clutch switch  61  serving as the operation detection switch for the operation lever, starting switch  41 , a starter magnet  62 , a starter motor  63 , a battery  64 , a regulator  65 , the headlight  16 , a generator  66 , an ignition control unit  67  serving as the ignition control means, an engine stop switch  35 , and an ignition coil  68 . The general load circuit  71  includes the cooling fan motor  25  and the tail light  29 . Specifically, the electric circuit is characterized in that the general load circuit  71  can be disconnected from the main circuit  60  through the relay means  70 . The ignition control unit  67  is the control unit for driving the relay  70 . 
   In the main circuit  60 , turning on both the clutch switch  61  and the starting switch  41  allows the starter motor  63  to be rotated using the battery  64 . 
   The relay means  70  turns on when the engine speed is a predetermined value, which is slightly lower than an idle speed, or more. The relay means  70  turns on to supply current from the battery and/or the generator to general loads, thus turning the cooling fan motor  25  and lighting up the tail light  29 . 
   A control circuit for the relay  70  is integrated with the ignition control unit receiving an engine speed signal. This helps reduce the number of parts used and makes the circuit more compact. 
   The headlight  16  is directly connected to the generator  66 . This makes the generator  66  shoulder the burden of supplying electricity for headlight  16 . This, in turn, reduces loads on the battery  64 , thus extending the life of the battery  64 . The relay  70  can be built compactly, since there is no need to pass current for the headlight to the relay  70 . 
     FIG. 7  is an operation flowchart at the starting of the vehicle according to the present invention. STXX represents a step number (where XX is the actual number). The vehicle according to the present invention is capable of being kick started. An operation flow for kick starting will be described with reference to another figure. 
   ST 01 : A determination is made as to whether or not the clutch switch is turned on. Specifically, an affirmative determination is made by gripping the clutch lever shown in  FIG. 3 . 
   ST 02 : A determination is made as to whether or not the starting switch is on. Specifically, an affirmative determination is made by pressing the starting switch  41  shown in  FIG. 3 . 
   ST 03 : The starter magnet  62  is energized causing current to flow from the battery  64  to the starter motor via the starter magnet  62 , thus turning the starter motor. 
   ST 04 : When the engine turns over (or starts to rotate), current is supplied from the generator to the ignition coil  68  through the ignition control unit  67 , thus causing a spark plug to produce a prescribed spark. 
   ST 05 : This starts the engine. 
   ST 06 : At the same time, current is supplied from the generator  66  to the headlight, thus turning on the headlight. 
   ST 07 : A determination is made as to whether or not an engine speed Ne has reached a predetermined value (e.g., 60% of the idle speed). 
   ST 08 : If an affirmative determination is made in ST 07 , the relay means is turned on. 
   ST 09 : This causes the cooling fan motor as a general load to start turning, and the tail light to light up. 
   The vehicle is now able to run, since energization of the general load has been started and the engine is in a rotating state. 
   The operation flow described heretofore is given for descriptive purposes of explaining operations of the electric circuit shown in  FIG. 6 .  FIG. 6  should be taken as being correct for any portions of the operation flow that are inaccurate. 
   To bring the engine that has been started to a stop, it is necessary to simply press the engine stop switch  35  shown in  FIGS. 3 and 6 . 
   In accordance with the preferred embodiment of the present invention described above, turning on both the clutch switch and the starting switch is the condition for starting. The clutch switch may, however, be replaced by a front brake switch or any other operation detection switch. 
   To state it another way, the conditions for starting are: the operation of the operation lever+turning on of the start switch. 
     FIG. 8  is an operation flowchart for the starting of the vehicle through kick starting. 
   ST 11 : The kick start pedal is depressed for activation. 
   ST 12 : A crankshaft of the engine turns and current is supplied from the generator to the ignition coil  68  through the ignition control unit  67 , thus causing the spark plug to produce a prescribed spark. 
   ST 13 : This starts the engine. 
   ST 14 : At the same time, current is supplied from the generator  66  to the headlight, thus turning on the headlight. 
   ST 15 : A determination is made as to whether or not the engine speed Ne has reached a predetermined value (e.g., 60% of the idle speed). 
   ST 16 : If an affirmative determination is made in ST 15 , the relay means is turned on. 
   ST 17 : This causes the cooling fan motor as a general load to start turning, and the tail light to light up. 
   The vehicle is now able to run, since energization of the general load has been started and the engine is in a rotating state. 
   To bring the engine that has been started to a stop, it is necessary to simply press the engine stop switch  35  shown in  FIGS. 3 and 6 . 
   In accordance with the preferred embodiment of the present invention, the invention is applied to a motorcycle. The present invention is nonetheless applicable to a three-wheeled vehicle and a four-wheeled vehicle. The present invention is therefore applicable to a general vehicle. The present invention is preferably applied to a vehicle not provided with any principal switch. 
   In this detailed description of the preferred embodiments, reference is made to the accompanying drawings, which form a part hereof, and within which are shown by way of illustration specific embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the invention.