JPH11294177A - Accessories driving device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the fuel consumption of a vehicle by providing a small auxiliary engine separate from a main engine for vehicle traveling, driving accessories by the auxiliary engine and stopping the main engine when the driving force for traveling is not needed, and driving the accessories by the main engine when the driving force for traveling is needed. SOLUTION: It is determined whether a main engine for vehicle traveling is stopped or not, in the case of stop, it is determined whether an air conditioner 4 is in operation or not, and when it is in operation, an operator turns on one electromagnetic clutch CA2 in a switching device 10 disposed in an input pulley 19 on the auxiliary engine 7 side for driving the air conditioner. The rotation of the air conditioner 4 driven by the main engine 1 is transmitted to the auxiliary engine 7 to be started. It is determined whether a designated delay time elapses or not, and if yes, the completion of starting the auxiliary engine 7 is recognized to turn off the other electromagnetic clutch CA1 disposed on the input pulley 14 of the main engine 1 side. Thus, the drive of the air conditioner is switched from the main engine to the auxiliary engine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an auxiliary device driving device for a vehicle.

[0002]

2. Description of the Related Art As a conventional vehicle accessory driving device, as shown in Japanese Patent Application Laid-Open No. 8-79915, a vehicle accessory is driven by an engine. In some cases, the machine can be driven. This means that in a hybrid vehicle, a driving system between an engine and a generator / motor is provided with a clutch and a driving force transmission mechanism located on the motor side from the clutch to transmit driving force to auxiliary machines such as an alternator, a power steering pump, and an air conditioner. Provide. Then, during operation of the engine, the clutch is closed, the engine operates the generator / motor as a generator, and the alternator is driven. When the engine is stopped, the clutch is opened, the generator / motor is operated as a motor, and the alternator or the like is driven by the output.

[0003]

However, in such a conventional vehicle accessory drive device, since a hybrid vehicle is premised, power consumption is reduced when the accessory is driven by a generator / motor. It will be great. In addition, when driving with an engine, the alternator, power steering pump, air conditioner, vacuum pump, transmission hydraulic power source, and many other auxiliary equipment are driven, so the engine becomes large, and when the auxiliary equipment load is minimum, the engine efficiency is reduced. Will drop.

Further, when the vehicle is stopped, unnecessary power steering pumps, vacuum pumps, and transmission hydraulic pressure sources are driven, and wasteful energy consumption is large. The present invention has been made in view of the above-described conventional problems, and uses a highly efficient small engine for driving auxiliary equipment when the vehicle does not need a driving force for traveling as in the case of stopping or further deceleration. Accordingly, the object is to improve the fuel efficiency of the vehicle.

[0005]

Therefore, according to the present invention, as shown in FIG. 1, at least one small (small displacement) auxiliary engine different from the main engine for running the vehicle is provided. A switching device that can switch the driving of the auxiliary equipment between the main engine and the sub engine, and a means for determining whether or not driving power for traveling is required. By driving the auxiliary equipment by the engine and stopping the main engine, when the driving force for traveling is required, the auxiliary equipment is driven by the main engine and the sub engine is stopped,
A control device for controlling the main engine, the sub engine, and the switching device is provided to constitute a vehicle accessory drive device.

[0006] In the invention according to claim 2, the switching device is provided with an input pulley driven by a main engine and an input pulley driven by a sub engine arranged side by side on a drive shaft of an auxiliary machine. An electromagnetic clutch is interposed between the pulley and each of the pulleys. In the invention according to claim 3, the accessory is an air conditioner compressor.

According to a fourth aspect of the present invention, the accessory is an air conditioner compressor and an alternator. In the invention according to claim 5, the means for judging the necessity of the driving force for traveling in the control device determines that the vehicle does not need the driving force for traveling, the vehicle stops, and the driving force for traveling is required. In this case, the vehicle starting state is detected.

According to a sixth aspect of the present invention, the control device cranks the sub engine by the main engine when switching from the main engine to the sub engine. In the invention according to claim 7, the control device cranks the main engine by the sub engine when switching from the sub engine to the main engine.

[0009]

According to the first aspect of the present invention, when the vehicle does not need a driving force for traveling, such as when the vehicle is stopped or when the vehicle is decelerated, the auxiliary machine is driven by the small auxiliary engine. ,
The fuel efficiency can be improved by stopping the main engine, that is, by switching the power required for driving the auxiliary machinery to the small sub-engine, which generates more fuel than the main engine, to generate fuel. In addition, when driving power for traveling is required, the auxiliary engine is driven by the main engine and the auxiliary engine is stopped, so that fuel consumption is reduced as compared with the case where auxiliary equipment is continuously driven by the auxiliary engine. Can be achieved.

According to the second aspect of the present invention, two input pulleys driven by the main engine and the sub engine are provided side by side on the drive shaft of the auxiliary machine, and the electromagnetic clutch is provided between the drive shaft and each input pulley. By interposing the switching device, the switching device can be configured compactly, which is advantageous on a vehicle. According to the invention according to claim 3, by targeting the air conditioner compressor, the air conditioner can be efficiently used when the vehicle stops.

According to the fourth aspect of the invention, the alternator is used in addition to the air conditioner compressor, so that the battery can be efficiently charged when the vehicle is stopped. According to the invention of claim 5, by detecting the vehicle stop state and the vehicle start state, switching the sub engine when the vehicle stops and switching to the main engine when starting the vehicle, necessary and sufficient control can be performed.

According to the sixth aspect of the present invention, when switching from the main engine to the sub engine, the sub engine is cranked by the main engine to reduce the jerky feeling of the auxiliary drive system accompanying the switching, and The starter for the secondary engine can be eliminated. According to the invention according to claim 7, when switching from the sub-engine to the main engine, the main engine is cranked by the sub-engine, so that the jerky feeling of the auxiliary drive system accompanying the switching is reduced, and The use frequency of the starter can be reduced, and the life of the starter can be improved.

[0013]

Embodiments of the present invention will be described below. First, a first embodiment will be described.
FIG. 2 is a front view of the engine system showing the first embodiment, and FIG. 3 is a plan view of the same.

Main engine for driving the vehicle (main internal combustion engine) 1
Is driven by the crank pulley 2 via the belt 3
Air conditioner compressor (hereinafter simply referred to as air conditioner) 4,
The water pump 5 and the alternator 6 can be driven. In addition to the main engine 1 for running the vehicle, a small-sized (displacement of about 50 to 250 cc) sub-engine (sub-internal combustion engine) 7 is provided exclusively for driving auxiliary equipment. The air conditioner 4 can be driven via the belt 9.

Here, a switching device 10 for switching the driving of the air conditioner 4 between the main engine 1 and the sub engine 7 is provided on the drive shaft of the air conditioner 4. That is, two input pulleys driven by the main engine 1 and two input pulleys driven by the sub-engine 7 are provided side by side on the drive shaft of the air conditioner 4, and an electromagnetic pulley is provided between the drive shaft and each input pulley. The clutches CA1 and CA2 are interposed.

More specifically, as shown in FIG.
An input pulley (main engine side input pulley) 14 driven by the main engine via a bearing 13 is rotatably mounted on the casing of the air conditioner 4 via a bearing 13 while the clutch plate 12 is fixed to the drive shaft 11 of the air conditioner. The input pulley 14 is supported and provided with a claw member 16 which is driven by the electromagnetic coil 15 and can be engaged with the clutch plate 12. The clutch plate 12, the electromagnetic coil 15 and the claw member 16 constitute an electromagnetic clutch CA <b> 1. It is.

Here, when the electromagnetic clutch CA1 is in the OFF state, the pawl member 16 is disengaged from the clutch plate 12, and in this state, the rotation of the input pulley 14 by the main engine is not transmitted to the drive shaft 11, and the electromagnetic clutch CA1 is in the ON state. The pawl member 16 projects and engages with the clutch plate 12, and in this state, the rotation of the input pulley 14 by the main engine is transmitted to the drive shaft 11. Also,
While the clutch plate 17 is fixed to the drive shaft 11 of the air conditioner 4, an input pulley (sub-engine-side input pulley) 19 driven by the sub-engine via the bearing 18 is relatively rotated on the drive shaft 11 via the bearing 18. The input pulley 19 is freely supported, and a claw member 21 driven by the electromagnetic coil 20 and engageable with the clutch plate 17 is provided inside the input pulley 19, and the clutch plate 17, the electromagnetic coil 20 and the claw member 21
An electromagnetic clutch CA2 is configured.

Here, when the electromagnetic clutch CA2 is also in the OFF state, the pawl member 21 is disengaged from the clutch plate 17, and in this state, the rotation of the input pulley 19 by the sub engine is not transmitted to the drive shaft 11, and the electromagnetic clutch CA2 is in the ON state. Then, the pawl member 21 projects and engages with the clutch plate 17, and in this state, the rotation of the input pulley 19 by the sub engine is transmitted to the drive shaft 11. Control of the switching device 10 (electromagnetic clutches CA1, CA2) is performed by a control device (control unit) (not shown) as shown in FIG.
And the flowchart of FIG.

FIG. 5 is a flow chart of the vehicle stop control. Before starting this control, the vehicle is running, a driving force for driving is obtained by the main engine, auxiliary equipment is driven by the main engine, and the auxiliary engine is stopped. In step 1 (referred to as S1 in the figure, the same applies hereinafter), it is determined whether or not the vehicle is stopped.
The vehicle stop is detected when a pulse signal is not output from a vehicle speed sensor that outputs a pulse signal every predetermined rotation of the axle within a predetermined period of time, and / or when a parking brake is activated.

In step 2, it is determined whether the air conditioner is operating. If the air conditioner is not operating, the process proceeds to step 3, the main engine is stopped, and the present control is terminated. If the air conditioner is operating, the process proceeds to step 4 and subsequent steps. In this case, since the air conditioner is operating, the electromagnetic clutch CA1 of the input pulley on the main engine side for driving the air conditioner is ON.

In step 4, the electromagnetic clutch CA2 of the input pulley for driving the air conditioner is turned on. Thus, the rotation of the drive shaft of the air conditioner driven by the main engine is transmitted to the sub engine, and the sub engine is cranked. In step 5, fuel supply and ignition to the sub-engine are started to start the sub-engine. Note that the start of fuel supply or the like here may be delayed for a predetermined time from the start of cranking of the sub engine,
It may be performed after the rotation speed of the sub engine reaches a predetermined value.

In step 6, it is determined whether or not a predetermined delay time has elapsed. If the predetermined delay time has elapsed, it is considered that the start of the sub engine has been completed, and the process proceeds to step 7. In step 7, the electromagnetic clutch CA1 of the input pulley for the main engine for driving the air conditioner is turned off. Thus, the driving of the air conditioner is completely switched from the main engine to the sub engine.

In step 8, the main engine is stopped, and this control ends. FIG. 6 is a flowchart of the vehicle start control. In step 11, it is determined whether or not the vehicle is in a start state, that is, whether or not the vehicle is about to start based on a signal from a D range signal, a gear position signal, a brake switch, a clutch switch, an accelerator switch, etc. of the automatic transmission. Then, if the vehicle is in the starting state, the process proceeds to step 12.

In step 12, it is determined whether or not the sub engine is operating. If the sub-engine is not operating, the routine proceeds to step 13, where the main engine is started by the starter, and the control shifts to the normal control. When an air conditioner is used, the electromagnetic clutch C of the input pulley on the main engine side for driving the air conditioner is used.
Turn A1 ON. If the sub engine is operating, the process proceeds to step 14 and subsequent steps. In this case, since the sub-engine is being operated, the electromagnetic clutch CA2 of the sub-engine-side input pulley for driving the air conditioner is ON.

In step 14, the electromagnetic clutch CA1 of the input pulley on the main engine side for driving the air conditioner is turned on.
Thus, the rotation of the drive shaft of the air conditioner driven by the sub engine is transmitted to the main engine, and the main engine is cranked. In step 15, fuel supply and ignition to the main engine are started to start the main engine. Note that the start of fuel supply or the like here may be delayed for a predetermined time from the start of cranking of the main engine, or may be performed after the rotational speed of the main engine reaches a predetermined value.

In step 16, it is determined whether or not a predetermined delay time has elapsed. If it has elapsed, it is considered that the start of the main engine has been completed, and the process proceeds to step 17. Step 1
At 7, the electromagnetic clutch CA2 of the input pulley for driving the air conditioner is turned off. As a result, the operation of the air conditioner is completely switched from the sub engine to the main engine.

In step 18, the sub-engine is stopped, and the routine shifts to normal control. When the air conditioner is not used, the electromagnetic clutch CA1 of the input pulley on the main engine side for driving the air conditioner may be turned off. By such control, when the vehicle does not require driving power for traveling, the air conditioner is driven by the sub engine to stop the main engine, and when the vehicle is traveling, the auxiliary engine is driven by the main engine,
Stop the sub engine.

This is done for the following reason. When the load of the engine is small, such as when the vehicle is stopped, the main engine for traveling is in an idle state while driving the auxiliary equipment, and is in a condition where the fuel efficiency is poor as shown in the fuel efficiency map of the main engine in FIG. To run the engine, which increases fuel consumption. Also, in a vehicle using the idle-time engine stop control, when there is an air conditioner load or the like, the idle-time engine stop control has to be stopped,
The effect of reducing the fuel consumption by stopping the engine during idling disappears.

Accordingly, the present invention provides a vehicle which does not need to generate a driving force, that is, the driving power required for driving the vehicle under the driving condition where the output required of the engine is small.
As shown in FIG. 12, in order to generate the power, the fuel efficiency in the driving range when the vehicle is stopped is improved by switching to a small sub-engine that has better fuel efficiency than the main engine for traveling.

That is, when the vehicle is operated with the main engine having a displacement of 2500 cc, for example, under the operating conditions when the air conditioner is stopped, as shown in FIG.
psh (350 g of fuel consumption per one horsepower per hour), for example, when operating with a sub-engine with a displacement of 50 cc, as shown in FIG. 12, the fuel efficiency is 200 g / p.
sh, and fuel efficiency can be improved.

At this time, when the main engine and the sub engine are operated during traveling of the vehicle as in the case of low-speed constant-speed traveling, the load on the main engine is smaller than when the auxiliary is driven by the main engine. Since the engine driving amount is reduced, the fuel efficiency of the main engine is deteriorated as compared with a case where the auxiliary engine is also driven by the main engine. That is, as shown in FIG. 13, when the auxiliary engine is driven by the main engine, the fuel efficiency of the main engine is about 26%.
In contrast to 0 g / psh, the fuel efficiency of the main engine when auxiliary equipment is driven by the auxiliary engine is about 300 g / psh.

Therefore, in order to enhance the fuel consumption reduction effect by this method, the function of stopping the auxiliary engine by the auxiliary engine and stopping the auxiliary engine when the vehicle is running, that is, the driving of the auxiliary equipment mounted on the vehicle, Is selectively used by the two engines according to the driving condition of the vehicle. Next, a second embodiment will be described.

FIG. 7 is a front view of an engine system showing a second embodiment, and FIG. 8 is a plan view of the same. The main engine 1 for driving the vehicle can drive the air conditioner 4, the water pump 5, and the alternator 6 via the belt 3 by the crank pulley 2.

In addition to the main engine 1 for driving the vehicle, a small auxiliary engine 7 is provided exclusively for driving auxiliary equipment.
Belt 9 is driven by crank pulley 8 of sub engine 7.
, The air conditioner 4 and the alternator 6 can be driven. Here, a switching device 10 capable of switching the driving of the air conditioner 4 between the main engine 1 and the sub engine 7 is provided on the drive shaft of the air conditioner 4. That is, two input pulleys driven by the main engine 1 and two input pulleys driven by the sub-engine 7 are provided side by side on the drive shaft of the air conditioner 4, and an electromagnetic pulley is provided between the drive shaft and each input pulley. The clutches CA1 and CA2 are interposed (see FIG. 4).

Further, a switching device 10 'for switching the driving of the alternator 6 between the main engine 1 and the sub-engine 7 is provided on the drive shaft of the alternator 6. That is, similarly to the switching device 10, two input pulleys driven by the main engine 1 and two input pulleys driven by the sub engine 7 are provided side by side on the drive shaft of the alternator 6, and the drive shaft and each input Electromagnetic clutches CO1 and CO2 are interposed between the pulleys, respectively (see FIG. 4).

Switching device 10 (electromagnetic clutches CA1, CA
2) and switching device 10 '(electromagnetic clutches CO1, CO
The control of 2) is performed by a control device (control unit) not shown in accordance with the flowcharts of FIGS. FIG. 9 is a flowchart of the vehicle stop control. Before starting this control, the vehicle is running, a driving force for driving is obtained by the main engine, auxiliary equipment is driven by the main engine, and the auxiliary engine is stopped.

In step 21, it is determined whether or not the vehicle is stopped. If the vehicle is stopped, the process proceeds to step 22. Step 2
In 2, it is determined whether the air conditioner is operating. In step 23 or step 24, the battery voltage is detected, and it is determined whether or not the battery is NG (the battery needs to be charged).

When the air conditioner is not operating and the battery is OK
If (charging of the battery is unnecessary), the routine proceeds to step 25, where the main engine is stopped, and the present control is terminated. If the air conditioner is operating and the battery is NG, step 2
Proceed to 6. In this case, since the air conditioner is operating and the battery is NG, the electromagnetic clutch CA1 of the main engine-side input pulley for driving the air conditioner and the electromagnetic clutch CO1 of the sub-engine-side input pulley for driving the alternator are ON.

At step 26, the electromagnetic clutch CA2 of the sub-engine side input pulley for driving the air conditioner and the electromagnetic clutch CO2 of the sub-engine side input pulley for driving the alternator.
Turn 2 ON. Thereby, the rotation of the drive shaft of the air conditioner and the alternator driven by the main engine is transmitted to the sub engine, and the sub engine is cranked.

If the air conditioner is operating but the battery is OK, the process proceeds to step 27. In this case, since the air conditioner is operating, the electromagnetic clutch CA1 of the input pulley on the main engine side for driving the air conditioner is ON. Step 2
At 7, the electromagnetic clutch CA2 of the air conditioner driving auxiliary engine-side input pulley is turned on. Thus, the rotation of the drive shaft of the air conditioner driven by the main engine is transmitted to the sub engine, and the sub engine is cranked.

If the air conditioner is not operating but the battery is NG, the process proceeds to step 28. In this case, the battery NG
Therefore, the electromagnetic clutch CO1 of the alternator driving main engine-side input pulley is ON. In step 28, the electromagnetic clutch CO2 of the alternator driving auxiliary engine-side input pulley is turned on. Thus, the rotation of the drive shaft of the alternator driven by the main engine is transmitted to the sub engine, and the sub engine is cranked.

After the cranking of the sub engine in steps 26 to 28, the process proceeds to step 29. In step 29, fuel supply and ignition to the sub-engine are started, and the sub-engine is started. In step 30, it is determined whether or not a predetermined delay time has elapsed. If it has elapsed, it is considered that the start of the sub engine has been completed, and the process proceeds to step 31.

At step 31, the electromagnetic clutch CA1 of the main engine-side input pulley for driving the air conditioner and the electromagnetic clutch CO1 of the main engine-side input pulley for driving the alternator.
Turn 1 off. Thereby, the driving of the air conditioner and / or the alternator is completely switched from the main engine to the sub engine. In step 32, the main engine is stopped, and the present control ends.

FIG. 10 is a flowchart of control when the vehicle starts. In step 41, it is determined whether or not the vehicle is in the vehicle start state (the vehicle is about to start). If the vehicle is in the vehicle start state, the process proceeds to step 42. In step 42, it is determined whether or not the sub engine is operating. If the sub-engine is not operating, the routine proceeds to step 43, where the main engine is started by the starter, and the control shifts to the normal control. The electromagnetic clutch CO1 of the input pulley of the main engine for driving the alternator is ON.
When the air conditioner is used, the electromagnetic clutch CA1 of the main engine-side input pulley for driving the air conditioner is also turned on.

If the sub engine is operating, step 44
Proceed to the following. In this case, since the sub engine is running,
The electromagnetic clutch CA2 of the sub-engine side input pulley for driving the air conditioner and / or the electromagnetic clutch CO2 of the sub-engine side input pulley for driving the alternator are ON. In step 44, the electromagnetic clutch CO1 of the alternator driving auxiliary engine-side input pulley is turned on.

In step 45, the alternator power generation control is temporarily stopped. This is to reduce the load when starting the main engine. In step 46, the electromagnetic clutch CA2 of the input pulley for driving the air conditioner is temporarily turned off. This is to reduce the load when starting the main engine.

In step 47, the electromagnetic clutch CO1 of the alternator driving main engine-side input pulley is turned on. Thus, the rotation of the drive shaft of the alternator driven by the sub engine is transmitted to the main engine, and the main engine is cranked. In step 48, fuel supply and ignition to the main engine are started to start the main engine.

In step 49, it is determined whether or not a predetermined delay time has elapsed. If the predetermined delay time has elapsed, it is considered that the start of the main engine has been completed, and the flow proceeds to step 50. Step 5
At 0, the electromagnetic clutch CO2 of the alternator driving auxiliary engine-side input pulley is turned off. As a result, the drive of the auxiliary machine is completely switched from the sub engine to the main engine.

In step 51, the sub-engine is stopped, and the routine shifts to normal control. When an air conditioner is used, the electromagnetic clutch CA1 of the input pulley on the main engine side for driving the air conditioner is turned on. With such control, the auxiliary engine drives the air conditioner and / or the alternator to stop the main engine when the vehicle stops, which does not require driving force for running, and the auxiliary engine is driven by the main engine when the vehicle runs. Then, the sub engine is stopped.

In the above embodiment, when it is not necessary to drive the air conditioner (and the alternator) when the vehicle is stopped, the main engine is stopped in order to realize idle engine stop control (see FIG. 5). If the idle engine stop control is not performed in step 3 or 25) in FIG. 9, the operation may be continued without stopping the main engine.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of the present invention.

FIG. 2 is a front view of the engine system showing the first embodiment of the present invention.

FIG. 3 is a plan view of the above.

FIG. 4 is a configuration diagram of an accessory drive shaft part.

FIG. 5 is a flowchart of vehicle stop control according to the first embodiment;

FIG. 6 is a flowchart of vehicle start control according to the first embodiment;

FIG. 7 is a front view of an engine system showing a second embodiment of the present invention.

FIG. 8 is a plan view of the above.

FIG. 9 is a flowchart of vehicle stop control according to a second embodiment.

FIG. 10 is a flowchart of vehicle start control according to the second embodiment.

FIG. 11 is a diagram showing a fuel consumption rate map of a main engine.

FIG. 12 is a diagram showing a fuel efficiency map of a sub engine.

FIG. 13 is a diagram showing a fuel efficiency map of a main engine.

[Explanation of symbols]

Reference Signs List 1 main engine 2 crank pulley 3 belt 4 air conditioner (air conditioner compressor) 5 water pump 6 alternator 7 auxiliary engine 8 crank pulley 9 belt 10, 10 'switching device 11 drive shaft 12 clutch plate 13 bearing 14 input pulley (input pulley on main engine side) 15) Electromagnetic coil 16 Claw member 17 Clutch plate 18 Bearing 19 Input pulley (sub-engine side input pulley) 20 Electromagnetic coil 21 Claw member CA1 Main engine side input pulley electromagnetic clutch for driving air conditioner CA2 Secondary engine side input pulley electromagnetic clutch for driving air conditioner CO1 Alternator drive main engine side input pulley electromagnetic clutch CO2 Alternator drive sub engine side input pulley electromagnetic clutch

Claims (7)

[Claims] 1. A small auxiliary engine separate from a main engine for driving a vehicle, a switching device capable of switching at least a part of auxiliary machines between a main engine and an auxiliary engine, and a driving force for driving the vehicle. It has means for determining the necessity, when the driving force for traveling is not required, when the auxiliary machine is driven by the auxiliary engine, the main engine is stopped, and when the driving force for traveling is required, And a control device for controlling the main engine, the sub-engine, and the switching device so that the auxiliary engine is driven by the main engine to stop the sub-engine. 2. The switching device according to claim 1, wherein an input pulley driven by a main engine and an input pulley driven by a sub engine are arranged side by side on a drive shaft of an auxiliary machine. 2. The vehicle auxiliary device driving device according to claim 1, wherein an electromagnetic clutch is interposed. 3. The vehicle accessory drive device according to claim 1, wherein the accessory is an air conditioner compressor. 4. An apparatus according to claim 1, wherein said auxiliary equipment is an air conditioner compressor and an alternator.
The auxiliary device driving device for a vehicle according to the above. 5. The control device according to claim 1, wherein the means for determining whether or not the driving force for traveling is required includes determining whether the driving force for traveling is not required, stopping the vehicle, and determining when the driving force for traveling is required. The vehicle accessory driving device according to any one of claims 1 to 4, wherein a vehicle starting state is detected. 6. The vehicle according to claim 1, wherein the control unit cranks the sub engine by the main engine when switching from the main engine to the sub engine. Accessory drive. 7. The vehicle according to claim 1, wherein the control device cranks the main engine by the sub engine when switching from the sub engine to the main engine. Accessory drive.