JP2000261907A - Hybrid vehicle - Google Patents

Abstract

(57) [Problem] To provide a hybrid vehicle in which accessories can be downsized and the accessories can always be driven at an appropriate rotation speed even when the vehicle is running at a low speed. An auxiliary device (air conditioner compressor) is provided so as to be driven by an output shaft that outputs a driving force of an electric motor or an internal combustion engine, and a traveling friction clutch (for traveling) is provided between the output shaft and a driving wheel. CL) is interposed, and when the rotation speed Nd of the output shaft is lower than the appropriate rotation speed Nd1 of the auxiliary machine during traveling of the vehicle (S12, S14), the control means
The output of the driving force source is increased (S22, S24) and the traveling friction clutch is slipped (S26) so as to maintain the rotation speed Nd of the output shaft at or above the proper rotation speed Nd1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid vehicle, and more particularly, to an operation control technique of an auxiliary machine connected to a driving force source of a parallel hybrid vehicle.

[0002]

[Related Background Art] In recent years, an internal combustion engine (engine) has been mounted together with an electric motor (motor) as a driving force source of a vehicle.
2. Description of the Related Art A parallel hybrid vehicle capable of running by combining the output of an electric motor and the output of an internal combustion engine has been developed and put into practical use. In such a parallel hybrid vehicle,
An engine driving force transmission clutch (engine clutch) is provided between the electric motor and the internal combustion engine. An operation mode in which the engine clutch is disconnected to operate only the electric motor, and the electric motor and the internal combustion engine are connected by connecting the engine clutch. The vehicle can travel in a plurality of operation modes such as an operation mode in which both are operated.

[0003] Also, in a parallel hybrid vehicle, auxiliary equipment such as an air conditioner compressor is operated by a driving force source.
No. 5 discloses that an auxiliary device is connected to an output shaft on the electric motor side of the engine clutch so that the auxiliary device is connected regardless of whether only the internal combustion engine is operating or only the electric motor is operating. A drivable hybrid vehicle is disclosed.

[0004]

However, in the hybrid vehicle disclosed in the above publication, the driving range of the vehicle in which the rotational speed of the driving force source is low, such as at low speed, is reduced.
There is a problem that the rotation speed of the auxiliary machine also decreases, and the auxiliary machine cannot be driven at an appropriate rotation speed. That is, in the hybrid vehicle disclosed in the above publication, a traveling clutch (manual type) separate from the engine clutch is provided between the output shaft and the wheels.
While the vehicle is stopped, the traveling clutch can be disengaged and the accessory can be driven by the internal combustion engine or the electric motor. However, when the vehicle is running at low speed, power is applied to the wheels. Must be transmitted, the traveling clutch cannot be disconnected, and at this time, the auxiliary machine rotates at a low rotation speed corresponding to the rotation speed of the wheels, and there is a problem that sufficient output cannot be output. There is.

In this case, it is conceivable to use an auxiliary machine of a low-rotation high-output type capable of producing a sufficient output even at a low rotation, or to drive the auxiliary machine with a dedicated motor or the like. This is not preferable because it leads to an increase in weight, an accommodation space, and an increase in cost. The present invention has been made to solve such a problem. It is an object of the present invention to reduce the size of the accessory and always keep the accessory properly rotated even when the vehicle is running at a low speed. An object of the present invention is to provide a hybrid vehicle capable of driving at a speed.

[0006]

In order to achieve the above object, according to the first aspect of the present invention, in a hybrid vehicle, an auxiliary machine is driven by an output shaft for outputting a driving force of an electric motor or an internal combustion engine. A driving clutch is interposed between the output shaft and the drive wheels, and when the rotation speed of the output shaft falls below the proper rotation speed of the auxiliary machine during traveling of the vehicle, by the control means, In order to maintain the rotation speed of the output shaft at or above the proper rotation speed, the output of the driving force source is increased and the traveling clutch is slipped.

Therefore, for example, when the vehicle is in a low-speed running state, the running clutch is slipped to adjust the engagement state, and the electric motor or the internal combustion engine is driven while transmitting the necessary and sufficient driving force to the wheels. It is possible to increase the rotation speed of the engine and drive the accessory at an appropriate rotation speed. Therefore, without increasing the size of the auxiliary equipment by making the auxiliary equipment a low-rotation high-power type or driving it with a dedicated electric motor, etc. The low-speed running state of the vehicle can be ensured, and auxiliary equipment such as an air conditioner compressor can always be operated satisfactorily without insufficient output.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Referring to FIG. 1, a schematic configuration diagram of a parallel hybrid vehicle is shown.
The configuration of the hybrid vehicle according to the present invention will be described with reference to FIG. As shown in the figure, a parallel hybrid vehicle is equipped with an engine (internal combustion engine) 1 and a motor generator (electric motor) 10 as a driving force source (power plant). In the parallel hybrid vehicle of the present invention, the output shaft 2 of the engine 1 is connected to the output shaft 12 of the motor generator 10 via a friction clutch (hereinafter, referred to as an engine CL) 4 for transmitting engine driving force. ,
The output shaft 12 of the motor generator 10 is a continuously variable transmission 2
0, connected to the drive shaft 31 via the drive shaft 30.
Further, a driving friction clutch (hereinafter referred to as a driving CL) 32, a differential gear 3
The axle 36 is connected through the connection 4. And axle 3
A pair of wheels 38, 38 are connected to both ends of 6 as drive wheels.

The engine 1 is, for example, a water-cooled gasoline engine, and has a sufficient maximum output capable of driving the wheels 38 and 38 to run the vehicle. The engine CL 4 uses the hydraulic actuator 6 to move the clutch plate 4 b on the motor generator 10 side to the engine 1.
This is a hydraulic clutch device that is pressed and connected to the clutch plate 4a on the side, and the hydraulic actuator 6 is connected to the hydraulic pressure generation unit 40 via an oil passage.

The motor generator 10 is an electric motor that functions as both a motor and a generator, that is, a generator, and is configured so that a stator coil 16 surrounds a rotor coil 14 integrated with an output shaft 12. Then, the rotor coil 14, the stator coil 16
Is connected to a battery (secondary battery) 70 via the inverter 18. That is, the motor generator 10
The motor functions as a motor for rotating the output shaft 12 by energizing the stator coil 16 to generate a magnetic field and also energizing the rotor coil 14 to generate a magnetic field. By rotating the rotor coil 14 integrated with the output shaft 12 by the external force from the wheels 38 and 38 transmitted through the drive shaft 22 to generate a magnetic field, a current is generated in the rotor coil 14 and the battery 70 is charged. It functions as a generator to perform.

Then, the motor generator 10
When functioning as a motor, the output torque can be changed by changing the amount of current supplied to the rotor coil 14, while
When functioning as a generator, the stator coil 16
It is possible to adjust the amount of power generation by changing the amount of electricity to the power supply. Motor generator 10 is not limited to the above-described type, but may be of any type as long as it can freely control the torque.
For example, a motor having no coil in the rotor may be used.

An output shaft (output shaft of a driving force source) 12 is provided with an output pulley 42 coaxially therewith, while a relatively small air conditioner compressor (auxiliary machine) 46 is provided near the output shaft 12. An input pulley 44 is coaxially connected to a rotating shaft 47 of the air conditioner compressor 46 via an air conditioner compressor clutch (hereinafter, referred to as an air conditioner CL) 48. A belt 46 is wound around the output pulley 42 and the input pulley 44. Here, the air conditioner compressor clutch 48 is a clutch device that connects and disconnects a pair of clutch plates with an electric actuator 49, but may be a clutch device using a hydraulic actuator.

An engine rotation sensor 3 for detecting the rotation speed of the output shaft 2, that is, the engine rotation speed Ne is provided near the output shaft 2. An output shaft rotation sensor 13 for detecting the rotation speed, that is, the motor rotation speed Nm of the motor generator 10, and further, the shaft rotation speed of the output shaft (the rotation speed of the output shaft) Nd is provided.

The continuously variable transmission 20 includes an endless V-belt 26 wound around a drive pulley 22 and a driven pulley 24. For details, see drive pulley 22,
The driven pulley 24 includes a fixed pulley 22 a, a movable pulley 22 b, and a fixed pulley 24, each of which has a contact surface with each side surface of the V-belt 26 tapered along the both side surfaces.
a and a movable pulley 24b.
2b is a movable pulley 24
b is the output shaft 1 by the hydraulic actuator 29.
2. It is slidable along the drive shaft 31.

That is, in the continuously variable transmission 20, the hydraulic actuator 28 receives the supply of the hydraulic pressure from the hydraulic pressure generating unit 40 and slides along the output shaft 12, and the movable pulley 24b is moved by the hydraulic actuator 29 in accordance with this. When it slides along the drive shaft 30, the position where the V-belt 26 is wound around moves in the radial direction, whereby the speed ratio is continuously and continuously changed. The continuously variable transmission 20 is already known, and a detailed description thereof will be omitted.

The traveling CL 32 includes a hydraulic actuator 3
3, the clutch plate 32 on the differential gear 34 side
This is a hydraulic clutch device similar to the engine CL4 described above, which presses and connects b to the clutch plate 32a on the continuously variable transmission 20 side. The hydraulic actuator 33 is connected to the hydraulic pressure generating unit 40 via an oil passage. The electronic control unit (ECU) 50 is a central processing unit (CPU)
The engine 1 and the motor generator 10
A main control device for controlling various operations of an electric vehicle such as an air conditioner. On the input side, an air conditioner switch (air conditioner SW) for operating an air conditioner is provided in addition to the above-described engine rotation sensor 3, output shaft rotation sensor 13, and the like. 52, a wheel speed sensor 5 for detecting the rotation speed of the wheel 30, that is, the wheel speed Vw
4. An accelerator position sensor (APS) 56 and the like, which are connected to the accelerator pedal and detect the operation amount of the accelerator pedal, that is, the accelerator opening θacc which is the required output amount, are connected. When the wheel speed Vw is detected by the wheel speed sensor 54, the ECU 50 calculates the vehicle speed V based on the wheel speed information Vw. On the other hand, ECU
On the output side of the engine 50, in addition to the inverter 18, the hydraulic pressure generating unit 40, the electric actuator 49, etc., the engine 1
Are connected to a fuel injection valve and an ignition coil (both not shown).

Hereinafter, the operation of the hybrid vehicle configured as described above will be described. In such a hybrid vehicle, during normal running, the motor generator 10 functions as a motor according to the output request amount from the APS 56, and the motor running is preferentially performed. Then, for example, when the motor torque is likely to be insufficient with respect to the output request amount from the APS 56, the engine CL4
Is connected appropriately, and control is performed such that the output of the engine 1 is supplied to the wheels 38, 38 additionally or independently.

Incidentally, in the hybrid vehicle,
The air conditioner compressor 46 is operated by the output shaft 12 of the motor generator 10, and the operation of the air conditioner compressor 46 is affected by the running state of the vehicle. However, in the hybrid vehicle according to the present invention, control is performed such that the air conditioner compressor 46 operates properly regardless of the running state of the vehicle.

The control of the air conditioner compressor according to the present invention when the air conditioner compressor 46 is driven to operate the air conditioner, that is, the operation of the hybrid vehicle of the present invention will be described below. Referring to FIG. 2, a control routine for controlling the air conditioner compressor is shown in a flowchart, and will be described with reference to the flowchart (control means).

First, in step S10, the air conditioner SW
It is determined whether or not 52 has been turned on to operate the air conditioner. If the determination result is true (Yes) and it is determined that the air conditioner SW52 is on, step S12 is performed.
Proceed to. In step S12, it is determined whether or not the shaft rotation speed Nd detected by the output shaft rotation sensor 13 is lower than a predetermined value, that is, an appropriate rotation speed Nd1 required to obtain a sufficient output from the air conditioner compressor 46. Is determined. That is, it is determined whether or not the air conditioner is sufficiently effective. If the result of the determination is true (Yes) and it is determined that the shaft rotation speed Nd is lower than the appropriate rotation speed Nd1 and the air conditioner is not in a sufficiently effective state, the process proceeds to step S14.

In step S14, it is determined whether or not the shaft rotation speed Nd is a value 0, that is, whether or not the vehicle speed V is a value 0 while the vehicle is stopped. If the determination result is true (Ye
If it is determined in s) that the shaft rotation speed Nd is 0, the process proceeds to step S16. In step S16,
The traveling CL 32 is cut. That is, in a state where the shaft rotation speed Nd is the value 0 and the vehicle is stopped, the air conditioner compressor 46 connected to the output shaft 12 cannot be driven. The connection between the output shaft 12 and the wheels 38, 38 in the stopped state is interrupted.

After the traveling CL 32 is cut, step S
At 18, the air conditioner CL48 is connected and the air conditioner compressor 46 is operable. In step S20, it is determined whether or not the engine CL4 is in a connected state. That is, it is determined whether or not the connection of the engine CL4 is being operated in accordance with the output request amount from the APS 56, and whether or not the output of the engine 1 is used as the driving force even at this time. The judgment result is true (Yes) and the engine CL
If it is determined that No. 4 is in the connected state, the process proceeds to step S22.

In step S22, the engine speed Ne is adjusted to the proper speed Nd1 in response to the determination in step S20.
The output of the engine 1 is increased so that Note that, in practice, when the shaft rotation speed Nd is 0, the engine CL
If the engine 4 remains connected, the engine 1 stalls, so that the engine CL4 is normally disconnected. That is, when the shaft rotation speed Nd is the value 0, normally, the determination result of step S20 is false (No), that is, it is determined that the engine CL4 is in the disconnected state, and the process then proceeds to step S24.

When the engine CL4 is in a disconnected state, the output of the engine 1
6 cannot be activated. Therefore, step S24
Then, the power supplied to the motor generator 10 is increased to increase the rotation speed of the motor generator 10 so that the motor rotation speed Nm becomes the proper rotation speed Nd1. As a result, even when the vehicle is stopped, the rotating shaft 12 can always rotate at the proper rotation speed Nd1, and the air conditioner compressor 46 can operate without any output shortage due to the output of either the engine 1 or the motor generator 10. It will be driven well.

On the other hand, if the determination result of step S14 is false (N
o), that is, when the shaft rotation speed Nd is not the value 0 but is between the value 0 and the appropriate rotation speed Nd1 (0 <Nd <Nd1), that is, the vehicle is running at a low speed without stopping. If not, the process proceeds to step S26. In this case, since the vehicle is traveling, the traveling CL 32 is completely driven as described above.
Cannot be cut off. Therefore, in the air conditioner compressor control according to the present invention, in step S26, control for sliding the traveling CL 32, that is, slip control is performed.

In the slip control, while the vehicle speed V is maintained, the air conditioner compressor 46 always operates at the proper rotational speed Nd1.
A control is performed to adjust the degree of engagement between the clutch plate 32a and the clutch plate 32b of the traveling CL 32 so as to rotate. For this purpose, for example, as shown in FIG. 3, when the speed ratio of the continuously variable transmission 20 is fixed to Lo (low) and the shaft rotation speed Nd is the appropriate rotation speed Nd1, the vehicle speed V and the appropriate engagement CL32 for traveling required to obtain a combined state
A map indicating the relationship with the supply hydraulic pressure to the CL 32 for driving is prepared in advance, and the supply hydraulic pressure to the traveling CL 32 in an appropriate slip state is read from the map according to the vehicle speed V. Note that, in the figure, the shaft rotation speed Nd is equal to the proper rotation speed Nd.
1 or more, that is, the vehicle speed V is a value V1 corresponding to the appropriate rotation speed Nd1.
In the above, the hydraulic pressure supplied to the traveling CL 32 is constant, which indicates that the slip control is no longer necessary if the vehicle speed V is equal to or higher than the value V1.

After the slip control of the traveling CL 32 is performed, the process proceeds to step S18, where the air conditioner CL48 is connected as in the case of the stop, and it is determined in step S20 whether the engine CL4 is in the connected state. I do. If the result of the determination in step S20 is true (Yes) and it is determined that the engine CL4 is in the connected state, the process proceeds to step S22, and the engine speed Ne becomes the appropriate speed Nd1 as described above. The output of the engine 1 is increased.

On the other hand, if the determination result of step S20 is false (N
If it is determined in o) that the engine CL4 is in the disconnected state, the process proceeds to step S24, where the power supplied to the motor generator 10 is set so that the motor rotation speed Nm becomes the proper rotation speed Nd1 as described above. And increase the rotation speed. That is, when the shaft rotation speed Nd is between the value 0 and the appropriate rotation speed Nd1 (0 <Nd <Nd1) and the vehicle is running at a low speed, the running CL 32
The rotation speed of the engine 1 or the motor generator 10 is increased while the slip control is performed so as to slide the vehicle at an appropriate degree of engagement.

In this way, the output shaft 12 can always be rotated at the proper rotation speed Nd1 while maintaining the vehicle speed V as it is. Thus, even when the vehicle is traveling at a low speed, the air conditioner compressor 46 can be operated satisfactorily without a shortage of output, and the air conditioner can be sufficiently operated.

Further, this makes it possible to always favorably rotate the air conditioner compressor 46 at high speed regardless of the running state of the vehicle.
Does not need to be a low-rotation, high-power type, but can be small and inexpensive, and can reduce costs. If the determination in step S10 is false (No), that is, the air conditioner SW
If it is determined that the air conditioner 52 is turned off, it is not necessary to operate the air conditioner compressor 46, so the process proceeds to step S30, and the traveling CL 32 is maintained in the connected state as usual.

If the result of the determination in step S12 is false (N
o), that is, when it is determined that the shaft rotation speed Nd is equal to or higher than the appropriate rotation speed Nd1, it can be determined that the air conditioner compressor 46 has already been sufficiently operated without insufficient output. In this case, the slip control is performed. In step S28, the air conditioner CL48 is immediately connected. Then, in step S30, the traveling CL 32 is maintained in the connected state as usual.

In the above embodiment, the air conditioner compressor 46 is used as an auxiliary device. However, the present invention is not limited to this. The auxiliary device may be an alternator, a power steering pump, or the like. The present invention can be suitably applied to any auxiliary machine driven by the power source.

[0033]

As described above in detail, according to the hybrid vehicle of the first aspect of the present invention, not only when the vehicle is stopped, but also when the vehicle is running at a low speed. It is possible to increase the rotation speed of the electric motor or the internal combustion engine while transmitting the necessary and sufficient driving force to the wheels to drive the auxiliary equipment at an appropriate rotation speed. The condition can be ensured and auxiliary equipment such as an air conditioner compressor can always be operated satisfactorily without insufficient output.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a hybrid vehicle according to the present invention.

FIG. 2 is a flowchart showing a control routine of air conditioner compressor control according to the present invention.

FIG. 3 is a map showing a relationship between a vehicle speed V and a hydraulic pressure supplied to a traveling CL 32 required to obtain an appropriate engagement state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine (internal combustion engine) 4 Friction clutch for transmitting engine driving force (engine CL) 6 Hydraulic actuator 10 Motor generator (electric motor) 12 Output shaft 32 Traveling friction clutch (CL for traveling) 33 Hydraulic actuator 40 Oil pressure generating unit 46 Air conditioner compressor (Auxiliary equipment) 48 Air conditioner compressor clutch (Air conditioner CL) 49 Electric actuator 50 Electronic control unit (ECU) 70 Battery

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tadashi Takemura 5-33-8 Shiba, Minato-ku, Tokyo Inside Mitsubishi Motors Corporation (72) Inventor Takeshi Asano 5-33-8 Shiba 5-chome, Minato-ku, Tokyo Mitsubishi F-term (reference) in the Automotive Industry Co., Ltd. PG04 PI16 PU01 PU22 PU25 RB08 RE03 SE04 SE05 SE08 TB01 TE02 TO22

Claims (1)

[Claims] A driving power source having an electric motor and an internal combustion engine, and outputting a vehicle driving output from at least one of the electric motor and the internal combustion engine; and an auxiliary device driven by an output shaft of the driving power source. A traveling clutch interposed between the output shaft and the drive wheel; and when the rotation speed of the output shaft is lower than the appropriate rotation speed of the auxiliary device during traveling of the vehicle, the rotation speed of the output shaft is adjusted to the appropriate speed. Control means for increasing the output of the driving force source and keeping the traveling clutch slip so as to maintain the rotation speed or higher.