WO2014006816A2

WO2014006816A2 - Saddle type vehicle

Info

Publication number: WO2014006816A2
Application number: PCT/JP2013/003449
Authority: WO
Inventors: Tetsuhiko Nishimura; Kosei Maebashi
Original assignee: Yamaha Hatsudoki Kabushiki Kaisha
Priority date: 2012-07-03
Filing date: 2013-05-31
Publication date: 2014-01-09
Also published as: TW201408866A; WO2014006816A3; WO2014006816A4

Abstract

A saddle type vehicle includes an engine, a getting-on detection section that detects getting-on of a driver, an idling-stop control section that stops the engine and switches the engine into an idling-stop state, an accelerator grip to be operated by a driver, an accelerator operation detection section that detects an operation of the accelerator grip, an engine restart control section that restarts the engine when a predetermined operation of the accelerator grip is detected during the idling-stop state of the engine, and a traveling start control section that permits the vehicle to start traveling on condition that getting-on of a driver has been detected by the getting-on detection section after the engine is restarted.

Description

SADDLE TYPE VEHICLE

The present invention relates to a saddle type vehicle using an engine as a power source.

Patent Literature 1 discloses an engine stop/start control device that automatically stops an engine when a vehicle stops and automatically starts an engine when a throttle is opened while a seat switch is on in an engine automatically stopped state.

Japanese Unexamined Patent Application Publication No. H11-257123

With the configuration described in Patent Literature 1, the engine in an automatically stopped state cannot be restarted unless a driver gets on a vehicle, and this is inconvenient in some cases. For example, in the case of a saddle type vehicle, a driver may get off the vehicle and walk while pushing the vehicle. In the configuration described in Patent Literature 1, in such a case where a driver walks while pushing the vehicle, the engine in an automatically stopped state cannot be restarted. Therefore, it is impossible that the engine is started in advance when a driver walks while pushing a vehicle, so that the vehicle cannot start traveling only by turning the accelerator grip immediately after the driver gets on the vehicle. For example, on a bad-weather day or in the night, etc., a driver may walk while pushing a vehicle over a long time with the headlight on. Specifically, a driver may want to move a vehicle safely by increasing the visibility so that his/her position can be recognized by other riders, etc. In such a case, the driver may want to keep the engine in the driving state to prevent the battery voltage from decreasing so that the vehicle can be restarted again. Further, when the engine is automatically stopped in the daytime, a user hardly becomes aware of turning-on of the headlight or indicators indicating an idling-stop state. Therefore, the user may mistake this automatic stop for a stop state made by turning-off of the main switch, and may fail to turn the main switch off. When the engine is automatically stopped, the main switch is kept conductive, so that the headlight and other electric components can be energized. Therefore, the engine may be left automatically stopped over a long time while the headlight is left on, and the battery may be depleted accordingly. Further, if a user leaves the vehicle while the main switch is on, the vehicle can be easily stolen.

It is considered that these problems can be reduced by enabling automatic restart of the engine even when a driver does not get on the vehicle. Specifically, by enabling automatic restart of the engine according to an accelerator operation by a driver even when the driver walks while pushing the vehicle, the vehicle can be started to travel immediately after the driver gets on the vehicle, and the battery can be prevented from being depleted. Further, the accelerator grip is easily moved when the vehicle rides over a bump when it is put into a garage in a state where a driver walks while pushing the vehicle after the engine is automatically stopped. The engine is therefore likely to be automatically restarted, and the user can easily re-recognize that the engine is in an automatically stopped state. The user can perform an operation for turning the main switch off as appropriate.

Thus, allowing automatic restart of the engine in a state where a driver walks while pushing the vehicle brings many benefits. On the other hand, the engine is automatically restarted and the driving force of the engine is transmitted to the vehicle and the vehicle may start traveling unintentionally. This is not preferable, and the convenience of the vehicle is deteriorated.

A preferred embodiment of the present invention provides a saddle type vehicle including an engine, a getting-on detection section that detects getting-on of a driver, an idling-stop control section that stops the engine and switches the engine into an idling-stop state when a predetermined idling-stop condition is satisfied during an idling state of the engine, an accelerator grip to be operated by a driver to adjust a throttle opening degree of the engine, an accelerator operation detection section that detects an operation of the accelerator grip, an engine restart control section that restarts the engine when a predetermined operation of the accelerator grip is detected during the idling-stop state of the engine, and a traveling start control section that permits the vehicle to start traveling on the condition that getting-on of a driver has been detected by the getting-on detection section after the engine is restarted.

With this configuration, when the engine is in an idling state, that is, when the engine is driven at an idling rotation speed, if the idling-stop conditions are satisfied, the engine is automatically stopped and switched into an idling-stop state. Accordingly, wasteful fuel consumption during a short stop as in the case of waiting at a traffic light can be prevented. On the other hand, during an idling-stop state, when a driver performs a predetermined operation of the accelerator grip, the engine is restarted. At this time, without setting getting-on of a driver as a condition, the engine is restarted. Therefore, in a case where a driver walks while pushing the saddle type vehicle, the engine can be restarted by an operation of the accelerator grip as appropriate. On the other hand, even after the engine is restarted, the vehicle is not permitted to start traveling unless getting-on of a driver is detected. Therefore, even after the engine is restarted, the vehicle does not start traveling unintentionally. When a driver gets on the vehicle, the vehicle is permitted to start traveling, so that after the engine is automatically stopped by waiting at a traffic light, restart of the engine and traveling start of the vehicle can be smoothly performed without a problem.

Thus, while unintentional traveling start of the vehicle when a driver has not got on the vehicle is avoided, the engine in an idling-stop state can be permitted to restart even when the driver walks while pushing the saddle type vehicle. Therefore, even when a driver walks while pushing the vehicle, the engine can be restarted by a predetermined operation of the accelerator grip. Accordingly, by starting the engine in advance when a driver walks while pushing the vehicle, the vehicle can be started to travel immediately after the driver gets on the vehicle, and the engine can be started for preventing the battery from being depleted. The accelerator grip may move depending on the situation during transportation such as a case in which an impact is applied when the vehicle rides over a bump as the driver walks while pushing the vehicle. The engine may restart accordingly. This can remind the user of an engine stop state made not by turning-off of the main switch but by idling-stop control. Therefore, the user can take a measure such as turning-off of the main switch as appropriate, so that unintentional depletion of the battery can be avoided.

Restart of the engine when a user walks while pushing a saddle type vehicle is intentionally performed by the user as appropriate for safety and security, and provides an effect of reminding the user that the engine is in an automatically stopped state, so that this is not wasteful fuel consumption.

Even when getting-on of the driver is detected and the vehicle is permitted to start traveling, the vehicle does not necessarily start traveling immediately. For example, in a preferred embodiment of the invention, in a state where the vehicle is permitted to start traveling, when a driver operates the accelerator grip and the throttle of the engine accordingly opens and the engine output increases, in response to this, the driving force of the engine is transmitted to the wheel and the vehicle starts traveling.

The saddle type vehicle according to a preferred embodiment of the present invention further includes a rotation speed responsive clutch that transmits a driving force of the engine to a wheel in response to the engine rotation speed reaching a predetermined transmission rotation speed, and an engine output control section that controls an output of the engine. In this case, the traveling start control section limits the output of the engine by the engine output control section so that the engine rotation speed is less than the transmission rotation speed when getting-on of a driver is not detected by the getting-on detection section. With this configuration, when getting-on of a driver is not detected, the output of the engine is limited, so that the engine rotation speed is controlled to be less than the transmission rotation speed. Accordingly, the rotation speed responsive clutch does not transmit the driving force of the engine to the wheel, so that unintentional traveling start of the saddle type vehicle can be avoided.

A configuration in which a driving force generated by the engine is selectively transmitted to the wheel by a motor type clutch or a hydraulic clutch instead of the rotation speed responsive clutch, can also be adopted. For example, in this case, the operations of these clutches may be controlled according to the engine rotation speed, etc.

The engine output control section may include a fuel supply amount adjusting means that adjusts a fuel supply amount to the engine according to the engine rotation speed. The engine output control section may include a retarding means that retards an ignition time of the engine according to the engine rotation speed. The engine output control section may further include an air amount adjusting means that adjusts an air amount to be taken into the engine by an electronic throttle. With these configurations, by adjusting the fuel supply amount, the ignition time, or the intake air amount, the engine output can be limited, and accordingly, unintentional traveling start of the vehicle can be avoided.

The saddle type vehicle according to a preferred embodiment of the present invention further includes an engine stop control section that stops the engine in response to detection of a predetermined engine stop trigger operation when the traveling start control section does not permit the vehicle to start traveling after the engine is restarted by the engine restart control section. With this configuration, after the engine is restarted, the engine can be stopped by a predetermined engine stop trigger operation performed by a driver. Accordingly, when a user does not want to restart the engine, the user can easily stop the engine, so that the convenience is improved. Examples of the engine stop trigger operation may include an operation of the accelerator grip by a predetermined operation amount or more, an operation of the accelerator grip at a predetermined operation speed or more, an operation that generates a vehicle speed of a predetermined value or more, an operation that generates an acceleration of a predetermined value or more, an operation that generates an input of a driving force into the vehicle, etc. These operations can be detected by an accelerator operation detection section, a vehicle speed sensor, an acceleration sensor, etc.

In a preferred embodiment of the present invention, the idling-stop condition includes a condition that the ratio of a cumulative time of an idling-stop state to an energization time during which the electric system of the saddle type vehicle is energized is a predetermined threshold or less. Specifically, when the ratio of a cumulative time of an idling-stop state to the energization time increases, switching to the idling-stop state is prohibited. Accordingly, excessive depletion of the battery in the idling-stop state can be avoided, and a battery charge that reliably enables the engine to restart can be secured.

The saddle type vehicle according to a preferred embodiment of the present invention further includes a motor to be driven for starting the engine, a battery that supplies electric power to the motor, and a deterioration detection section that detects deterioration of the battery. In this case, preferably, the engine restart control section is configured to restart the engine by driving the motor, and the idling-stop condition includes a condition that deterioration of the battery has not been detected by the deterioration detection section. With this configuration, switching to the idling-stop state is not performed when the battery deteriorates, so that excessive depletion of the battery can be avoided and a battery charge that reliably enables the engine to start can be secured.

The saddle type vehicle preferably further includes a power generator that is driven by a driving force of the engine to generate electric power, and the battery is arranged to be charged by the electric power generated by the power generator.

In a preferred embodiment of the present invention, the idling-stop condition includes conditions that the vehicle speed is a predetermined value or less, that the accelerator operation detection section detects a full closing degree of the accelerator opening degree, that the engine rotation speed is in an idling rotation speed range, and that the getting-on detection section detects getting-on of a driver. With this configuration, on the conditions that the vehicle speed is a predetermined value or less, the accelerator opening degree is a full closing degree, the engine rotation speed is in an idling rotation speed range, and in addition, a condition that a driver has got on the vehicle, switching of the engine into an idling-stop state is permitted. If switching into an idling-stop state were permitted even when getting-on of a driver is not detected, it might become impossible to start the vehicle to travel in case of malfunction of the getting-on detection section. In the configuration described above, if the getting-on detection section malfunctions and getting-on of a driver is not detected, the engine is not switched into the idling-stop state, so that engine restart control from an idling-stop state and traveling start limitation control according to no-detection of getting-on are not performed. Therefore, there is no possibility that it becomes impossible to start the vehicle to travel.

The engine is preferably a fuel injection type engine. With this configuration, by controlling a fuel injection amount, switching into an idling-stop state, restart from an idling state, and traveling start limitation control after the engine restarts can be performed.

Other elements, features, steps, characteristics and advantages of the present invention will more apparent from the following detailed description of the preferred embodiments with reference to the attached drawings.

Fig. 1 is an illustrative side view for describing a configuration of a motorcycle as an example of a saddle type vehicle according to a preferred embodiment of the present invention. Fig. 2 is a perspective view showing a configuration example of a handle of the motorcycle. Fig. 3 is a horizontal sectional view of a power unit of the motorcycle. Fig. 4 is a schematic view for describing a configuration relating to an engine installed in the power unit. Fig. 5 is a block diagram for describing an electrical configuration relating to control of the engine. Fig. 6 is a block diagram for describing a functional configuration of an ECU (Electronic Control Unit) that controls the engine. Fig. 7 is a flowchart for describing a flow from start of the engine to switching into an idling-stop state. Fig. 8 is a flowchart for describing a detailed example of judgment (Step S5 in Fig. 7) of idling-stop conditions. Fig. 9 is a flowchart for describing an example of control for restarting the engine in an idling-stop state. Fig. 10 is a block diagram for describing a configuration relating to control of an engine in a motorcycle according to another preferred embodiment of the present invention.

Fig. 1 is an illustrative side view for describing a configuration of a saddle type vehicle according to a preferred embodiment of the present invention. Fig. 1 shows a scooter type motorcycle 1 as an example of a saddle type vehicle. In the following description, for convenience, based on the point of view of a rider (driver) getting on the motorcycle 1, the front-rear, left-right, and up-down directions of the motorcycle 1 are defined.

A motorcycle 1 includes a vehicle main body 2, a front wheel 3, and a rear wheel 4. The vehicle main body 2 includes a vehicle body frame 5, a handle 6, a seat 7, and a power unit 8. The vehicle body frame 5 includes a down tube 9 disposed on the front side, and a pair of left and right side frames 10 disposed at the rear of the down tube 9. The down tube 9 extends forward to the diagonally upper side, and to an upper end portion thereof, a head pipe 11 is fixed. On this head pipe 11, a steering shaft 20 is supported turnably. To the lower end of the steering shaft 20, a pair of left and right front forks 12 are fixed. To an upper end portion of the steering shaft 20, the handle 6 is attached, and to the lower end portions of the front forks 12, a front wheel 3 is attached rotatably. The side frames 10 are curved in substantially S shapes, and extend rearward to the diagonally upper side from the lower end of the down tube 9. On the side frames 10, a seat 7 is supported. To the vicinities of the intermediate portions of the side frames 10, a bracket 13 is fixed. On the bracket 13, the power unit 8 is supported so as to swing up and down via a pivot shaft 14. The power unit 8 is a unit swing type engine unit. Above the power unit 8, an air cleaner 23 for cleaning the air to be taken into the engine is disposed. Cushion units 15 are laid between the vicinities of the rear end portions of the side frames 10 and the rear end portion of the power unit 8. On the rear end portion of the power unit 8, a rear wheel 4 is supported rotatably.

The vehicle body frame 5 is covered by a vehicle body cover 16 made of resin. The vehicle body cover 16 includes a foot board 17 that is provided below the front side of the seat 7 and provides a foot placing portion, a front cover 18 that covers the head pipe 11, a side cover 19 that covers the region below the seat 7, and a handle cover 21 that covers the handle 6. A battery 25 is housed in a space covered by the side cover 19 below the seat 7, and is supported on the vehicle body frame 5. A headlight 22 is provided to be exposed forward from the handle cover 21, and supported on the handle 6. A main switch 40 for supplying electric power charged in the battery 25 to the motorcycle 1 is disposed on, for example, the rear surface (surface facing the seat 7) of the front cover 18. The main switch 40 may be a key switch that is operated by using a key held by a user.

Fig. 2 is a perspective view showing a configuration example of the handle 6, and shows a configuration viewed down from a driver seated on the seat 7. The handle 6 includes a handle bar 30 extending in the left-right direction, and grips 31 and 32 provided on the left end and right end of the handle bar 30. Ahead of the left grip 31, a rear wheel brake lever 38 for actuating a rear wheel brake is disposed, and ahead of the right grip 32, a front wheel brake lever 39 for actuating a front wheel brake is disposed. The right grip 32 is attached turnably in a predetermined angle range around the axis of the handle bar 30, and is an accelerator grip for an accelerating operation. The handle bar 30 is covered by the handle cover 21. The handle cover 21 is provided with a speed meter 33 and an engine rotation speed meter 34. On the speed meter 33, an indicator 41 is disposed. The indicator 41 is turned on when the engine is switched into an idling-stop state by idling-stop control described later. Near the accelerator grip 32, a starter button 35 for starting the engine is disposed. Near the left grip 31, a turn signal switch 36, a headlight switch 37, etc., are disposed.

Fig. 3 is a horizontal sectional view of the power unit 8, and shows a section viewed from above, and the upper side corresponds to the front side of the motorcycle 1, and the lower side corresponds to the rear side of the motorcycle 1. The power unit 8 includes a starter motor 43, a power generator 44, an engine 45, a V-belt type continuously variable transmission 46, and a centrifugal clutch 47.

The engine 45 includes a crankshaft 48 extending in the left-right direction, a crankcase 49 that houses the crankshaft 48, a cylinder block 50 extending forward from the crankcase 49, a cylinder head 51 fixed to the tip end portion of the cylinder block 50, and a head cover 52 fixed to the tip end portion of the cylinder head 51. The cylinder block 50 and the cylinder head 51 constitute a cylinder 53. Inside the cylinder block 50, a piston 54 is housed slidably. The piston 54 and the crankshaft 48 are joined by a connection rod 55. A combustion chamber 56 is defined by the cylinder block 50, the cylinder head 51, and the piston 54.

On the right of the crankcase 49, the power generator 44 is disposed. The power generator 44 includes a rotor 58 coupled to the right end portion of the crankshaft 48, and a stator coil 59 supported on the crankcase 49. When the crankshaft 48 rotates, the rotor 58 rotates around the stator coil 59, and an electromotive force is generated in the stator coil 59. By this electromotive force generated in the stator coil 59, the battery 25 (refer to Fig. 1) is charged.

The V-belt type continuously variable transmission 46 includes a transmission case 60, a drive pulley 61, a driven pulley 62, and a V-belt 63 wound around these pulleys. The drive pulley 61 is attached to the left end portion of the crankshaft 48. The driven pulley 62 is attached to a main shaft 65 rotatably around the main shaft 65. In detail, the driven pulley 62 includes a movable pulley piece 62a whose position in the axial direction of the main shaft 65 changes and a fixed pulley piece 62b whose position in the axial direction does not change. Both of the

pulley pieces

62a and 62b are rotatable with respect to the main shaft 65. The main shaft 65 is held rotatably on the transmission case 60. Rotation of the main shaft 65 is transmitted to a rear wheel shaft 67 via a gear mechanism 66. The rear wheel shaft 67 is supported rotatably on the transmission case 60. To the rear wheel shaft 67, the rear wheel 4 is fixed.

Rotation of the driven pulley 62 is transmitted to the main shaft 65 via the centrifugal clutch 47. The centrifugal clutch 47 includes a primary side rotor 71 supported rotatably on the main shaft 65 and a secondary side rotor 72 as a clutch plate that is coupled to the main shaft 65 and rotates together with the main shaft 65. The secondary side rotor 72 has a tubular portion surrounding the primary side rotor 71. The driven pulley 62 is coupled to the primary side rotor 71, and the primary side rotor 71 rotates together with the driven pulley 62. However, the movable pulley piece 62a can be freely displaced along the axial direction of the main shaft 65, and a compression coil spring 70 is interposed between the movable pulley piece 62a and the primary side rotor 71. The primary side rotor 71 is provided with a shoe 73. The shoe 73 is configured to come into contact with the inner surface of the tubular portion of the secondary side rotor 72 when the rotation speed of the primary side rotor 71 increases to a predetermined speed. Therefore, when the rotation speed of the driven pulley 62 increases, the shoe 73 comes into contact with the secondary side rotor 72, and accordingly, the rotation of the driven pulley 62 is transmitted to the main shaft 65 via the centrifugal clutch 47, and a driving force is applied to the rear wheel 4.

The drive pulley 61 includes a movable pulley piece 61a disposed in the crankcase 49, and a fixed pulley piece 61b disposed on the side away from the crankcase 49. The movable pulley piece 61a is coupled to the crank shaft 48 so that the movable pulley piece 61a can be displaced in the axial direction of the crankshaft 48 with respect to the crankshaft 48, and rotates together with the crankshaft 48. The fixed pulley piece 61b is fixed to the crankshaft 48, and rotates together with the crankshaft 48 in a state where it is not displaced in the axial direction of the crankshaft 48. On the crankcase 49 side with respect to the movable pulley piece 61a, a holder plate 64 is fixed to the crankshaft 48. A roller 68 is disposed between the holder plate 64 and the movable pulley piece 61a. The roller 68 is positioned near the rotation center when the rotation speed of the crankshaft 48 is low, and the movable pulley piece 61a is positioned close to the crankcase 49 accordingly. On the other hand, as the rotation speed of the crankshaft 48 becomes higher, the roller 68 moves away from the rotation center due to a centrifugal force, and presses the movable pulley piece 61a and brings it closer to the fixed pulley piece 61b.

When the rotation speed of the crankshaft 48, that is, the engine rotation speed is low, and the distance between the movable pulley piece 61a and the fixed pulley piece 61b is long, the V-belt 63 is positioned at a small-diameter position close to the crankshaft 48. Accordingly, on the driven pulley 62, the V-belt 63 is positioned at a large-diameter position away from the main shaft 65. This state is shown in Fig. 3. In this state, the rotation speed of the driven pulley 62 is low, so that the centrifugal clutch 47 is kept in a disconnected state. When the engine rotation speed increases, the roller 68 is displaced by a centrifugal force to move away from the crankshaft 48, and accordingly, the movable pulley piece 61a moves closer to the fixed pulley piece 61b, so that the V-belt 63 moves to a large-diameter position of the drive pulley 61. Accordingly, on the driven pulley 62, the V-belt 63 widens the distance between the movable pulley piece 62a and the fixed pulley piece 62b by pushing these against a force of the compression coil spring 70 and moves to the small-diameter position. As a result, the rotation speed of the driven pulley 62 increases, so that the centrifugal clutch 47 is switched into a connected state, and a driving force of the engine 45 is transmitted to the rear wheel 4. The centrifugal clutch 47 is a rotation speed responsive clutch that is switched into a connected state in response to an engine rotation speed. A minimum engine rotation speed when the centrifugal clutch 47 is switched into a connected state is referred to as "transmission rotation speed."

The starter motor 43 is fixed to the crankcase 49, and is actuated by electric power supplied from the battery 25. The rotative force of the starter motor 43 is transmitted to the crankshaft 48 by the gear mechanism 69 housed in the crankcase 49. Therefore, when starting the engine 45, the starter motor 43 is actuated, and accordingly, the crankshaft 48 is rotated.

Fig. 4 is a schematic view for describing a configuration relating to the engine 45. On the cylinder head 51, an intake opening 81 and an exhaust opening 82 facing the combustion chamber 56 are defined. Further, on the cylinder head 51, an ignition plug 80 is disposed to face the combustion chamber 56. An intake valve 83 is disposed in the intake opening 81, and an exhaust valve 84 is disposed in the exhaust opening 82. The intake valve 83 opens and closes the intake opening 81, and the exhaust valve 84 opens and closes the exhaust opening 82. The intake valve 83 and the exhaust valve 84 are driven by a valve gear (not illustrated) that interlocks with the crankshaft 48. The intake opening 81 is connected to the intake port 85, and the exhaust opening 82 is connected to the exhaust port 86.

The engine 45 is a fuel injection type engine in the present preferred embodiment. Specifically, in the intake port 85, an injector 87 is disposed on the upstream side of the intake valve 83. The injector 87 is arranged to inject fuel toward the intake opening 81. The injector 87 is supplied with fuel from a fuel tank 88 via a fuel hose 89. Inside the fuel tank 88, a fuel pump 90 is disposed. The fuel pump 90 pressure-feeds fuel inside the fuel tank 88 to the fuel hose 89.

In the intake port 85, a throttle body 91 is disposed on the upstream side of the injector 87. The throttle body 91 holds a throttle valve 92, an intake pressure sensor 93, an intake temperature sensor 94, and a throttle opening degree sensor 95. The throttle valve 92 may be, for example, a butterfly valve including a plate-shaped valve element disposed turnably inside the intake port 85. The throttle valve 92 is mechanically coupled to the accelerator grip 32 via a wire 99 in the present preferred embodiment. Specifically, when the accelerator grip 32 is operated, according to the operation direction and the operation amount, the throttle valve 92 is displaced (in the present preferred embodiment, angular displacement) to change the throttle opening degree. The position of the throttle valve 92 is detected by the throttle opening degree sensor 95. The throttle valve 92 and the accelerator grip 32 are mechanically joined to each other, so that in the present preferred embodiment, the throttle opening degree sensor 95 functions as an accelerator operation detection section that detects an accelerator opening degree as an accelerator command value as well as the throttle opening degree. The accelerator opening degree is an operation amount of the accelerator grip 32. The intake pressure sensor 93 detects the pressure of the intake air. The intake temperature sensor 94 detects the temperature of the intake air.

A crank angle sensor 96 for detecting a rotation angle of the crankshaft 48 is attached to the crankcase 49. An engine temperature sensor 97 for detecting the temperature of the engine 45 is attached to the cylinder block 50.

Fig. 5 is a block diagram for describing an electrical configuration relating to control of the engine 45. Outputs of the sensors 93 to 97 are input into the ECU (electronic control unit) 100. To the ECU 100, other sensors such as a vehicle speed sensor 98, an acceleration sensor 131, etc., may be connected as appropriate. The vehicle speed sensor 98 is a sensor that detects the vehicle speed of the motorcycle 1, and may be a wheel speed sensor that detects rotation speeds of the

wheels

3 and 4. The acceleration sensor 131 is a sensor that detects the acceleration of the motorcycle 1. To the ECU 100, a getting-on detection unit 28 for detecting whether a driver has sat on the seat 7 (refer to Fig. 1), that is, whether a driver has got on the motorcycle, is connected. The getting-on detection unit 28 may be a load detection unit that detects a load (weight) applied onto the seat 7 as illustrated in Fig. 1. An example of the load detection unit is a seat switch that becomes conductive when a load of a predetermined value or more is applied onto the seat 7.

Based on output signals of the sensors 93 to 97, etc., the ECU 100 drives the fuel pump 90 and the injector 87 to control the fuel injection amount and the fuel injection timing. To the ECU 100, an ignition coil 79 is further connected. The ignition coil 79 stores electric power for causing spark discharge of the ignition plug 80 (refer to Fig. 4). The ECU 100 controls energization of the ignition coil 79 based on output signals of the sensors 93 to 97, etc., to control the ignition time (discharge timing of the ignition plug 80).

Further, the ECU 100 controls energization of the starter motor 43 to control the start of the engine 45.

The battery 25 is connected to a power supply line 26 via a fuse 27. The electric power stored in the battery 25 is supplied to the starter motor 43, the ECU 100, the ignition coil 79, the injector 87, the fuel pump 90, the indicator 41, etc., via the power supply line 26. The battery 25 is supplied with electric power that is generated by the power generator 44 and rectified and regulated by the regulator 78, and accordingly, during driving of the engine 45, the battery 25 is charged.

The main switch 40 is interposed in the power supply line 26. To the power supply line 26, on the side opposite to the battery 25 with respect to the main switch 40, a parallel circuit of brake switches 135 and 136 is connected. The brake switch 135 becomes conductive when the rear wheel brake lever 38 is operated, and is shut off when the rear wheel brake lever 38 is not operated. Similarly, the brake switch 136 becomes conductive when the front wheel brake lever 39 is operated, and is shut off when the front wheel brake lever 39 is not operated. The starter button 35 is connected in series to the parallel circuit of these brake switches 135 and 136, a diode 137 is connected in series to the starter button 35, and further, a coil of a relay 77 is connected to the diode 137. To the power supply line 26, the starter motor 43 is connected via the relay 77. Therefore, when the starter button 35 is turned on in a state where the rear wheel brake lever 38 or the front wheel brake lever 39 is operated, the relay 77 becomes conductive and the electric power of the battery 25 is supplied to the starter motor 43.

In the power supply line 26, to the side opposite to the battery 25 with respect to the main switch 40, the ECU 100, the ignition coil 79, the injector 87, the fuel pump 90, the indicator 41, etc., are connected. Specifically, when the main switch 40 becomes conductive, the electric power is supplied to the ECU 100, and the control operation of the ECU 100 is started.

The ECU 100 includes a voltage detection section 102 that detects a voltage (battery voltage) supplied from the power supply line 26. The ECU 100 further includes a drive control section 101 for driving actuators including the ignition coil 79, the injector 87, the fuel pump 90, the relay 77, the indicator 41, etc. The drive control section 101 includes a driving circuit for power supply to the actuators.

Between the diode 137 and the coil of the relay 77, the drive control section 101 of the ECU 100 is connected. Therefore, the ECU 100 can actuate the starter motor 43 by driving the relay 77 even when the starter button 35 is off.

The ECU 100 includes a driving state memory 105. The driving state memory 105 is used to store records of driving states of the motorcycle 1. In detail, the driving state memory 105 is used to store information on a time of an idling-stop state within an energization period of a predetermined time before the present time. The energization period is a period during which the main switch 40 is conductive and power is supplied to the electric system of the motorcycle 1. The electric system includes the ECU 100 and other electric components. The driving state memory 105 includes a storage medium that can hold stored content even in a state where the main switch 40 is shut off. In detail, the driving state memory 105 may include a programmable non-volatile memory such as an EEPROM (electrically erasable programmable read-only memory).

Fig. 6 is a block diagram for describing a functional configuration of the ECU 100. The ECU 100 includes a computer built in, and the computer executes programs to realize the functions of the function processing sections described below.

Specifically, the ECU 100 includes an idling-stop control section 111, an engine restart control section 112, a traveling start control section 113, an engine output control section 114, and an engine stop control section 115 as the function processing sections.

The engine output control section 114 controls the output of the engine 45. In detail, the engine output control section 114 includes a fuel supply control section 116 and an ignition control section 117. The fuel supply control section 116 controls the fuel injection amount and the fuel injection timing by controlling the fuel pump 90 and the injector 87. The ignition control section 117 controls a spark discharge time (ignition time) of the ignition plug 80 by controlling energization of the ignition coil 79. By controlling one or both of the fuel injection amount and the ignition time, the output of the engine 45 can be controlled. By cutting-off the fuel by setting the fuel injection amount to zero, the engine 45 can be stopped.

The idling-stop control section 111 stops the engine 45 and switches the engine into an idling-stop state when predetermined idling-stop conditions are satisfied during an idling state of the engine 45. The idling state is a state where the throttle opening degree is a full closing degree and the engine rotation speed is in an idling rotation speed range (for example, 2500 rpm or less). The idling-stop state is a state where the driving of the engine 45 is automatically stopped by control of the idling-stop control section 111. In detail, the idling-stop control section 111 stops fuel supply to the engine 45 by providing a fuel cut-off command to the engine output control section 114, and accordingly stops the engine 45.

The engine restart control section 112 restarts the engine 45 when a predetermined operation of the accelerator grip 32 is detected during the idling-stop state of the engine 45. Restart means restarting the engine 45 being in an idling-stop state. In detail, the engine restart control section 112 actuates the starter motor 43 by making the relay 77 (see Fig. 5) conductive by controlling the drive control section 101 and applies fuel supply control and an ignition control command to the engine output control section 114. Accordingly, the starter motor 43 is actuated and fuel is injected from the injector 87, and the ignition coil 79 spark-discharges and the engine 45 restarts.

The traveling start control section 113 permits the motorcycle 1 to start traveling on the condition that getting-on of a driver has been detected by the getting-on detection unit 28 after the engine 45 is restarted. In other words, the traveling start control section 113 prohibits traveling start of the motorcycle 1 unless getting-on of a driver is detected by the getting-on detection unit 28. In detail, prohibiting traveling start means a state where a driving force of the engine 45 is not transmitted to the rear wheel 4. Therefore, permitting traveling start means a state where transmission of a driving force of the engine 45 to the rear wheel 4 is permitted.

In detail, the traveling start control section 113 provides a command (output inhibiting command) to inhibit an output of the engine 45 to the engine output control section 114. The engine output control section 114 that received the output inhibiting command controls the output of the engine 45 so that the rotation speed of the engine 45 becomes lower than a predetermined transmission rotation speed. As described above, the transmission rotation speed is a lowest engine rotation speed for switching the centrifugal clutch 47 (see Fig. 3) as an example of a rotation speed responsive clutch into a connected state where the centrifugal clutch 47 transmits the rotation of the primary side rotor 71 to the secondary side rotor 72. Therefore, when the engine rotation speed is kept lower than the transmission rotation speed, the centrifugal clutch 47 is kept in a shut-off state where the primary side rotor 71 and the secondary side rotor 72 rotate independently of each other, and the driving force of the engine 45 is not transmitted to the rear wheel 4. The engine output control section 114 keeps the engine rotation speed lower than the transmission rotation speed regardless of the throttle opening degree by inhibiting the output of the engine 45 by performing one or both of control of the fuel injection amount and control of the ignition time when the engine output control section 114 receives an output inhibiting command.

After the engine 45 is restarted by the engine restart control section 112, when the traveling start control section 113 does not permit the motorcycle 1 to start traveling, the engine stop control section 115 stops the engine 45 in response to detection of a predetermined engine stop trigger operation. An example of the engine stop trigger operation may be an operation of the accelerator grip 32 for quickly closing or quickly opening the throttle. This operation can be detected by monitoring the output of the throttle opening degree sensor 95 that also serves as an accelerator operation detection section. Specifically, when the throttle opening degree change rate is a predetermined value or more, it can be judged that an accelerator operation for quickly closing or quickly opening the throttle has been performed. Another example of the engine stop trigger operation may be a predetermined amount or more of operation of the accelerator grip 32. For example, by judging that the throttle opening degree has reached a predetermined value or more from the output of the throttle opening degree sensor 95, it can be judged that the predetermined amount or more of operation of the accelerator grip 32 has been performed. When an engine stop trigger operation is detected, the engine stop control section 115 provides a fuel cut-off command to the engine output control section 114. In response to this, the engine output control section 114 sets the fuel injection amount to zero, and accordingly, the fuel supply to the engine 45 is cut off and driving of the engine 45 is stopped.

Fig. 7 is a flowchart for describing the flow from the start of the engine 45 to switching into the idling-stop state. In the case where the main switch 40 is conductive, when the starter button 35 is operated (Step S2) while the rear wheel brake lever 38 or the front wheel brake lever 39 is gripped (step S1), the relay 77 becomes conductive to supply the electric power of the battery 25 to the starter motor 43. Accordingly, the starter motor 43 is driven, and crank pulses from the crank angle sensor 96 are input into the ECU 100. Based on the crank pulses, the ECU 100 obtains a rotation angle of the crankshaft 48 (crank angle), and based on the obtained crank angle, performs the fuel injection control and the ignition control. Accordingly, the engine 45 starts and enters a driving state (Step S3).

The ECU 100 judges whether the battery 25 has been deteriorated in a period during which the starter motor 43 is energized and a cranking operation is performed, and writes a battery deterioration judgment flag that indicates whether the battery has been deteriorated in a memory installed inside (Step S4). The ECU 100 can judge whether the battery 25 has been deteriorated based on a battery voltage detected by the voltage detection section 102, for example. In detail, the ECU 100 monitors the battery voltage when the starter motor 43 is actuated, and when the battery voltage decreases to a predetermined threshold or less, the ECU 100 may perform a process of raising a battery deterioration judgment flag. The ECU 100 may perform a process of raising a battery deterioration judgment flag when the rotation speed of the crankshaft 48 when the starter motor 43 is actuated (rotation speed before starting the engine 43) is a predetermined threshold or less. Specifically, when the battery 25 is deteriorated and cannot supply sufficient electric power, the rotation speed of the crankshaft 48 rotated by the starter motor 43 becomes lower, so that deterioration of the battery 25 can be judged by utilizing this phenomenon.

When the engine 45 is in a driving state, the ECU 100 judges whether predetermined idling-stop conditions are satisfied (Step S5). When the idling-stop conditions are satisfied, the ECU 100 switches the engine 45 into an idling-stop state (Step S6). Specifically, fuel supply to the engine 45 is stopped and the fuel injection control and ignition control are stopped.

Fig. 8 is a flowchart for describing a detailed example of judgment of idling-stop conditions (Step S5 in Fig. 7). The ECU 100 judges whether the following conditions A1 to A7 are all satisfied (Steps S11 to S17).

Condition A1: The accelerator grip 32 is at a full-closing position. This condition is for confirming that a driver does not intend to transmit a driving force of the engine 45 to the rear wheel 4 that is a drive wheel. In the present preferred embodiment, the accelerator grip 32 and the throttle valve 92 are mechanically interlocked with each other by the wire 99, so that when the throttle opening degree sensor 95 detects full closing of the throttle valve 92, the accelerator grip 32 is at a full-closing position.

Condition A2: The vehicle speed is a predetermined value (for example, 3 km/h) or less. This condition is for confirming that the motorcycle 1 has stopped. In detail, the condition is that the vehicle speed sensor 98 detects a vehicle speed of a predetermined value or less.

Condition A3: Getting-on of a driver has been detected. Getting-on of a driver is detected by the getting-on detection unit 28. If the getting-on detection unit 28 malfunctions and the output thereof is not supplied to the ECU 100, getting-on of a driver is not detected. As described above, to restart the engine 45 in an idling-stop state, getting-on of a driver must be detected. If the getting-on detection unit 28 malfunctions and cannot detect getting-on of a driver, after the engine is switched into an idling-stop state, the engine 45 cannot be restarted. This failure can be avoided by the condition A3. Specifically, when the getting-on detection unit 28 malfunctions, the engine is not switched into an idling-stop state, so that a restart failure from the idling-stop state does not occur.

Condition A4: The engine rotation speed is a predetermined value (for example, 2500 rpm) or less. This condition is for confirming that the engine rotation speed is in an idling rotation speed range. The ECU 100 calculates an engine rotation speed based on a crank pulse generation period output by the crank angle sensor 96, for example.

Condition A5: The engine temperature is a predetermined value (for example, 60 degree) or more. This condition is for confirming that the engine 45 has been sufficiently warmed up, and can be easily restarted after the driving thereof is stopped. The ECU 100 judges the engine temperature based on an output signal of the engine temperature sensor 97.

Condition A6: The battery has not been deteriorated. A state where the battery has been deteriorated is a state where the battery 25 cannot supply enough electric power for starting the engine 45 to the starter motor 43. Specifically, not only a case where the battery 25 is deteriorated in performance due to aging, etc., but also a case where the output voltage of the battery decreases due to discharge of the battery 25 are included in the state that the battery 25 has been deteriorated. The process in Step S4 in Fig. 7 is a process of writing a battery deterioration judgment flag in a memory installed inside. Therefore, the judgment of the condition A6 may be judgment as to whether a battery deterioration judgment flag has been raised.

Condition A7: A ratio of an idling-stop time to an energization time is a predetermined value (for example, 40%) or less. The energization time is a time during which the main switch 40 is conductive, the motorcycle 1 is powered on, and the electric system of the motorcycle 1 is energized. The idling-stop time is a cumulative time during which the engine 45 is in an idling-stop state. In the present preferred embodiment, an idling-stop time in an energization time of a last predetermined time (for example, approximately 20 minutes) is measured, and based on this, a ratio of the idling-stop time to the energization time (approximately 20 minutes) is calculated. In detail, by using driving state records stored in the driving state memory 105, a ratio of an idling-stop time to an energization time is calculated. The driving state memory 105 consists of EEPROM, etc., as described above, and even when the main switch 40 is shut off, the stored content is held. Therefore, regardless of turning on/off operations of the main switch 40, driving state records in a last predetermined time are held in the driving state memory 105. Therefore, when the main switch 40 is made to be conductive, without waiting for elapse of the predetermined time, an accurate idling-stop ratio can be obtained, so that idling-stop control based on the idling-stop ratio can be properly performed.

When all of the conditions A1 to A7 are satisfied (YES in all of Steps S11 to S17), the ECU 100 increments a timer installed inside (Step S18) and judges whether the value of the timer has reached a predetermined value (for example, a value corresponding to 3 seconds) (Step S19). The timer measures a duration of a state where all of the conditions A1 to A7 are satisfied. When at least one of the conditions A1 to A7 is not satisfied (NO in any of Steps S11 to S17), the ECU 100 resets the timer to zero (Step S20). When the time measured by the timer reaches the predetermined value (for example, a value corresponding to 3 seconds), the ECU 100 judges that the idling-stop conditions have been satisfied and switches the engine 45 into an idling-stop state (Step S6). Specifically, the idling-stop condition is continuation of a state where all of the conditions A1 to A7 are satisfied for a predetermined time. In the idling-stop state, the ECU 100 turns the indicator 41 on.

Fig. 9 is a flowchart for describing an example of control for restarting the engine 45 being in an idling-stop state. The ECU 100 judges whether the operation amount of the accelerator grip 32, that is, the accelerator opening degree has exceeded a predetermined value by monitoring the output of the throttle opening degree sensor 95 (Step S31). When the accelerator opening degree does not exceed the predetermined value, the idling-stop state is continued. When the accelerator opening degree exceeds the predetermined value, the ECU 100 restarts the engine 45 (Step S32). Specifically, the ECU 100 actuates the starter motor 43 by making the relay 77 conductive, and starts the fuel injection control and ignition control. Accordingly, the engine 45 restarts.

The ECU 100 judges whether the battery 25 has been deteriorated during a period in which the starter motor 43 is energized and a cranking operation is performed, and writes a battery deterioration judgment flag indicating whether the battery has been deteriorated in the memory installed inside (Step S33). Details of this operation are the same as those in Step S4 of Fig. 7.

After restarting the engine 45, the ECU 100 judges whether a driver has got on the vehicle, that is, whether a driver has sat on the seat 7 by referring to the output of the getting-on detection unit 28 (Step S34). When a driver gets on the vehicle (Step S34: YES), the ECU 100 establishes a traveling start permitting state (Step S35). Specifically, the ECU 100 permits the engine rotation speed to increase over the transmission rotation speed. Therefore, the accelerator opening degree is increased by the operation of the accelerator grip 32, and in response to this, the throttle opening degree increases and the output of the engine 45 increases, and then, the engine rotation speed reaches the transmission rotation speed. Accordingly, the centrifugal clutch 47 is switched into a connected state, and the driving force of the engine 45 is transmitted to the rear wheel 4.

On the other hand, when getting-on of a driver is not detected by the getting-on detection unit 28 (Step S34: NO), the ECU 100 establishes a traveling start prohibiting state (Step S36). In the traveling start prohibiting state, even when the driver increases the accelerator opening degree and the throttle opening degree accordingly increases, the output of the engine 45 is limited, and the engine rotation speed does not reach the transmission rotation speed. Specifically, the ECU 100 limits the output of the engine 45 by reducing the fuel injection amount according to the engine rotation speed and retarding the ignition time (regarding control) so that the engine rotation speed does not increase even if the throttle opening degree increases. Accordingly, the engine rotation speed does not reach the transmission rotation speed, so that the centrifugal clutch 47 is kept in a disconnected state, and the driving force of the engine 45 is not transmitted to the rear wheel 4. Therefore, the motorcycle 1 is prevented from unintentionally starting traveling in a state where a driver does not get on it.

In the traveling start prohibiting state, in response to a predetermined engine stop trigger operation performed by a driver (Step S37), the ECU 100 stops the engine 45 (Step S38). For example, when the accelerator opening degree reaches a predetermined value or more, this is detected by the throttle opening degree sensor 95, and in response to this detection, the ECU 100 stops the engine 45 by stopping fuel supply to the engine 45. Therefore, when a driver does not sit on the seat 7, if the engine is restarted unintentionally, by increasing the accelerator opening degree, the engine 45 can be stopped immediately without shutting-off the main switch 40.

As described above, according to the present preferred embodiment, when the engine 45 is in an idling state, that is, when the engine is driven in an idling rotation speed range, if the idling-stop conditions are satisfied, the engine 45 is automatically stopped and switched into an idling-stop state. Accordingly, wasteful fuel consumption in such a case where the vehicle waits at a traffic light can be prevented. On the other hand, during the idling-stop state, when the driver operates the accelerator grip 32 by a predetermined amount or more, the engine 45 restarts (refer to Step S31 in Fig. 9). At this time, without setting getting-on of a driver as a condition, the engine 45 is restarted. Therefore, in such a case where a driver walks while pushing the motorcycle 1, by an operation of the accelerator grip 32, the engine 45 can be restarted as appropriate. On the other hand, even after the engine 45 is restarted, unless getting-on of a driver is detected, the motorcycle 1 is not permitted to start traveling (refer to Steps S34 to S36 in Fig. 9). Therefore, even after the engine 45 is restarted, the motorcycle 1 does not start traveling unintentionally. When a driver gets on the motorcycle 1, the motorcycle 1 is permitted to start traveling, so that after the engine 45 is automatically stopped by waiting at a traffic light, restart of the engine 45 and traveling start of the motorcycle 1 can be smoothly performed.

Thus, while unintentional traveling start of the motorcycle 1 when a driver does not get on the motorcycle is avoided, the engine 45 being in an idling-stop state can be permitted to restart even when the driver walks while pushing the motorcycle 1. Therefore, even when a driver walks while pushing the motorcycle, the engine 45 can be restarted by an operation of the accelerator grip 32. Accordingly, the engine 45 is started in advance when a driver walks while pushing the motorcycle, and immediately after the driver gets on the motorcycle, the motorcycle 1 can be started to travel, or the engine 45 can be started to prevent the battery 25 from being depleted.

When the accelerator grip 32 moves depending on the situation during transportation in such a case where an impact is applied when the motorcycle 1 rides over a bump as the driver walks while pushing the motorcycle, the engine 45 may restart. Accordingly, the user can be made to recognize that the engine stop state has been made not by shutting-off of the main switch 40 but by idling-stop control. Therefore, the user can take a measure such as shutting-off of the main switch 40 as appropriate, so that the battery 25 can be prevented from being depleted unintentionally. For example, when the user pushes the motorcycle 1 and puts it into a garage, if the motorcycle 1 rides over a bump, the accelerator grip 32 may move. The engine 45 restarts accordingly, and the motorcycle 1 can be prevented from being parked with the main switch 40 left conductive. In particular, if the headlight 22 is left on in the daytime, a driver hardly becomes aware of this. In this case, the motorcycle may be parked with the main switch 40 left conductive and the headlight 22 being left on for a long period of time although the engine 45 stops and the power generator 44 is not actuated. This greatly depletes the battery 25. With the configuration according to the present preferred embodiment in which the engine 45 is permitted to automatically restart without setting getting-on of a driver as a condition, forgetting to turn the main switch 40 off can be avoided, so that the battery 25 can be prevented from being depleted unintentionally.

Restart of the engine 45 when a user walks while pushing the motorcycle 1 may be intentionally performed by a user for safety and security as appropriate, and brings about an effect of reminding the user that the engine has been automatically stopped. This is not wasteful fuel consumption, therefore.

Further, according to the present preferred embodiment, after the engine 45 is restarted, by a predetermined engine stop trigger operation by a driver, the engine 45 can be stopped (see Steps S37 to S38 in Fig. 9). Accordingly, when the user does not want to restart the engine 45, the user can easily stop the engine 45, so that the convenience is improved. Specifically, even when the accelerator grip 32 moves and the engine 45 restarts while a user walks while pushing the motorcycle, the user can stop the engine 45 immediately only by operating, for example, the accelerator grip 32. Of course, when a user walks while pushing the motorcycle, even without an engine stop trigger operation, the engine 45 is automatically switched into an idling-stop state if the idling-stop conditions are satisfied (refer to Fig. 8).

Further, in the present preferred embodiment, the idling-stop conditions include a condition that the ratio of the cumulative time of the idling-stop state to the energization time during which the electric system of the motorcycle 1 is energized (time during which the main switch 40 is conductive) (idling-stop ratio) is a predetermined threshold or less (Step S17 in Fig. 8). Specifically, when the idling-stop ratio increases, switching into the idling-stop state is prohibited. Accordingly, the battery 25 can be prevented from being excessively depleted by the idling-stop state, so that a battery charge that reliably enables the engine 45 to restart can be secured.

Fig. 10 is a block diagram for describing a configuration relating to control of an engine in a motorcycle according to another preferred embodiment of the present invention. In the present preferred embodiment, a so-called electronic throttle device is applied. Specifically, the throttle valve 92 is driven by a throttle actuator 130 such as an electric motor. The operation amount (accelerator opening degree) of the accelerator grip 32 is detected by the accelerator opening degree sensor 133. An output signal of the accelerator opening degree sensor 133 is input into the ECU 100. The ECU 100 drives the throttle actuator 130 in response to the output signal of the accelerator opening degree sensor 133 and adjusts the throttle opening degree. The engine output control section 114 includes an intake amount adjusting section 118 for adjusting an intake air amount by controlling the throttle actuator 130.

With this configuration, control in which the throttle opening degree does not depend on the accelerator opening degree can also be performed. Specifically, even if there is a change in accelerator opening degree, the throttle opening degree can be changed. Therefore, it is possible that in a traveling start prohibiting state (refer to Step S36 in Fig. 9), even when an increase in accelerator opening degree is detected, the throttle opening degree is not increased, and the engine rotation speed can be prevented from increasing. Specifically, in a traveling start prohibiting state, the intake amount adjusting section 118 does not actuate the throttle actuator 130 even if the accelerator grip 32 is operated, and keeps the throttle opening degree at a full closing degree (not more than a value at which the engine rotation speed does not reach the transmission rotation speed). Thus, by adjusting the intake air amount to be taken into the engine 45, the driving force of the engine 45 can be prevented from being transmitted to the rear wheel 4 (refer to Fig. 1).

In the present preferred embodiment, the engine restart control section 112 performs engine restart control based on an output of the accelerator opening degree sensor 133 (Step S31 in Fig. 9). The engine stop control section 115 judges whether a predetermined engine stop trigger operation has been performed based on an output signal not of the throttle opening degree sensor 95 but of the accelerator opening degree sensor 133 (Step S37 in Fig. 9).

Two preferred embodiments of the present invention have been described above; however, the present invention can also be carried out in other preferred embodiments. For example, in the above-described preferred embodiments, a configuration in which the power transmission path between the engine 45 and the drive wheel (rear wheel 4) is connected/disconnected by the centrifugal clutch 47 is shown; however, the clutch that connects/disconnects the power transmission path may be realized by other modes such as a hydraulic clutch or an electromagnetic clutch. By controlling the hydraulic clutch or the electromagnetic clutch, etc., according to an engine rotation speed, etc., the same operation as in the case where the centrifugal clutch 47 is used can be realized.

In the above-described preferred embodiment, a scooter type motorcycle 1 is described by way of example; however, the present invention is also applicable to other motorcycles such as a moped type, a sport type, etc. Further, not only to motorcycles, the present invention is also applicable to other saddle type vehicles such as all-terrain vehicles and snowmobiles.

The present application corresponds to Japanese Patent Application No. 2012-149768 filed in the Japan Patent Office on July 3, 2012, and the entire disclosure of the application is incorporated herein by reference.

While preferred embodiments of the present invention have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing the scope of the present invention. The scope of the present invention, therefore, is to be determined solely by the following claims.

1 Motorcycle
2 Vehicle main body
3 Front wheel
4 Rear wheel
5 Vehicle body frame
6 Handle
7 Seat
8 Power unit
22 Headlight
25 Battery
26 Power supply line
28 Getting-on detection unit
32 Accelerator grip
35 Starter button
37 Headlight switch
40 Main switch
43 Starter motor
44 Power generator
45 Engine
46 V-belt type continuously variable transmission
47 Centrifugal clutch
48 Crankshaft
49 Crankcase
53 Cylinder
54 Piston
56 Combustion chamber
77 Relay
79 Ignition coil
80 Ignition plug
81 Intake opening
82 Exhaust opening
85 Intake port
86 Exhaust port
87 Injector
88 Fuel tank
90 Fuel pump
92 Throttle valve
95 Throttle opening degree sensor
96 Crank angle sensor
97 Engine temperature sensor
98 Vehicle speed sensor
100 ECU
101 Drive control section
102 Voltage detection section
105 Driving state memory
111 Idling-stop control section
112 Engine restart control section
113 Traveling start control section
114 Engine output control section
115 Engine stop control section
116 Fuel supply control section
117 Ignition control section
118 Intake amount adjusting section
130 Throttle actuator
131 Acceleration sensor
133 Accelerator opening degree sensor

Claims

A saddle type vehicle comprising:
an engine;
a getting-on detection section that detects getting-on of a driver;
an idling-stop control section that stops the engine and switches the engine into an idling-stop state when a predetermined idling-stop condition is satisfied during an idling state of the engine;
an accelerator grip to be operated by a driver to adjust a throttle opening degree of the engine;
an accelerator operation detection section that detects an operation of the accelerator grip;
an engine restart control section that restarts the engine when a predetermined operation of the accelerator grip is detected during the idling-stop state of the engine; and
a traveling start control section that permits the vehicle to start traveling on condition that getting-on of a driver has been detected by the getting-on detection section after the engine is restarted.
The saddle type vehicle according to Claim 1, further comprising:
a rotation speed responsive clutch that transmits a driving force of the engine to a wheel in response to the engine rotation speed reaching a predetermined transmission rotation speed; and
an engine output control section that controls an output of the engine, wherein
the traveling start control section limits the output of the engine by the engine output control section so that the engine rotation speed is less than the transmission rotation speed when getting-on of a driver is not detected by the getting-on detection section.
The saddle type vehicle according to Claim 2, wherein the engine output control section includes a fuel supply amount adjusting means that adjusts a fuel supply amount to the engine according to the engine rotation speed.
The saddle type vehicle according to Claim 2, wherein the engine output control section includes a retarding means that retards an ignition time of the engine according to the engine rotation speed.
The saddle type vehicle according to Claim 2, wherein the engine output control section includes an air amount adjusting means that adjusts an air amount to be taken into the engine by an electronic throttle.
The saddle type vehicle according to any one of Claims 1 to 5, further comprising: an engine stop control section that stops the engine in response to detection of a predetermined engine stop trigger operation when the traveling start control section does not permit the vehicle to start traveling after the engine is restarted by the engine restart control section.
The saddle type vehicle according to any one of Claims 1 to 6, wherein the idling-stop condition includes a condition that a ratio of a cumulative time of the idling-stop state to an energization time during which an electric system of the saddle type vehicle is energized is a predetermined threshold or less.
The saddle type vehicle according to any one of Claims 1 to 7, further comprising:
a motor to be driven for starting the engine;
a battery that supplies electric power to the motor; and
a deterioration detection section that detects deterioration of the battery, wherein
the engine restart control section is configured to restart the engine by driving the motor, and
the idling-stop condition includes a condition that deterioration of the battery has not been detected by the deterioration detection section.
The saddle type vehicle according to any one of Claims 1 to 8, wherein the idling-stop condition includes conditions that a vehicle speed is a predetermined value or less, that the accelerator operation detection section detects a full closing degree of an accelerator opening degree, that an engine rotation speed is in an idling rotation speed range, and that the getting-on detection section detects getting-on of a driver.
The saddle type vehicle according to any one of Claims 1 to 9, wherein the engine is a fuel injection type engine.