JP2010018077A - Hybrid automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hybrid automobile in a simple structure for achieving good user-friendliness and excellent fuel economy improvement effect. <P>SOLUTION: In a parallel hybrid automobile including an engine 1, a torque transmission control mechanism 2, a generator motor 3, and an axle system 4 which are sequentially connectable, a planetary gear mechanism 7 is used as the torque transmission control mechanism 2, and one axis (preferably, a carrier 72) is connected to the engine, and also connected to the generator motor (MG) 3 and the axle system 4 via a first one-way clutch 10. The other axis (preferably, internal gear 73) of the planetary gear mechanism 7 is connected to a brake 8, and the remaining one axis is connected to the generator motor (MG) 3 via a second one-way clutch 11. In this structure, the parallel hybrid automobile in the simple structure for achieving very good user-friendliness is achieved. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a hybrid vehicle, and more particularly to an improvement of a parallel hybrid hybrid vehicle in which an engine, one generator motor (MG), and an axle are connected in series.

  Conventionally, a parallel hybrid system in which an engine, one generator motor (MG), and an axle system are connected in series is known, for example, in Patent Document 1 below.

  In the hybrid vehicle of Patent Document 1, as illustrated in FIG. 1, the shaft-coupled MG and the axle system (usually including a speed reduction mechanism such as a transmission) are connected to the engine through a clutch. When the clutch is disengaged, torque transmission / reception between the MG and the axle system can be performed regardless of the engine, and when the clutch is connected, the engine torque can be applied to the MG and the axle system. When the axle system has a torque cutting function such as a clutch (for example, the transmission is set to the neutral position), the engine can be started by the MG with the clutch connected.

As another parallel hybrid system, a system in which the shaft-coupled engine and MG are connected to an axle system (usually including a speed reduction mechanism such as a transmission) through a clutch is also known.
JP 2000-213383 A

  However, in the method of Patent Document 1, it is difficult to start the engine with MG during the electric travel period in which the clutch is disengaged and the vehicle travels with MG, for example, and as a result, for example, the opportunity for idling stop is greatly reduced. There was a problem that the effect of improving fuel efficiency was reduced. Note that it is difficult to start the engine by the MG during the electric running because, for example, a normal motor has a reduced torque during high-speed rotation, and the clutch input shaft (MG shaft) is rotating. This is because the connection is not easy.

  Further, in the system in which the shaft-coupled engine and MG are connected to the axle system through the clutch, since the MG is directly connected to the engine, the resistance of the engine during driving is large, resulting in an improvement in fuel consumption. There was a problem of being lowered.

  Further, in the above-described conventional method, since the engine and MG have the same rotation speed, a large torque for starting the engine is generated, so that it is necessary to increase the size of the MG. In addition, the friction clutch as the clutch mechanism is large and heavy, and the maintenance work is complicated.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a hybrid vehicle that has a simple configuration, is easy to use, and has an excellent fuel efficiency improvement effect.

  The hybrid vehicle of the present invention is a hybrid vehicle including an engine, a torque transmission control mechanism, a generator motor, and an axle system that are arranged so as to be sequentially connectable. The torque transmission control mechanism has first, second, and third shafts. A planetary gear mechanism, a first one-way clutch for transmitting torque of the engine to the generator motor and an axle system, a second one-way clutch for transmitting torque of the generator motor to the engine, and a brake; The brake is provided in a housing and restrains the first shaft of the planetary gear mechanism, the engine is connected to the second shaft of the planetary gear mechanism, and the first one-way clutch is The second one-way clutch is disposed between the second shaft of the planetary gear mechanism and the generator motor and the axle system, and the second one-way clutch is connected to the generator motor and axle system and the planetary gear. It is set to its being arranged between the third shaft of the gear mechanism.

  In this way, it is possible to realize a hybrid vehicle that has a simple structure, is easy to use, and has an excellent fuel efficiency improvement effect.

  The advantages are listed in more detail. The engine can be started with a small generator motor, and the engine can be easily started even during electric travel. Furthermore, frequent engine ON / OFF is possible, so that the fuel consumption reduction effect is improved. Further, since there is no friction clutch and the brake mechanism is operated only at the moment of starting and is not involved in continuous power transmission, maintenance management is easy, life can be extended, and reliability can be improved. In addition, even when an automatic transmission is adopted as a transmission, only a small and inexpensive shifter is required, and a heavy, large and expensive clutch actuator is not required, resulting in a small size, light weight and low cost.

  In a preferred aspect, the planetary gear mechanism includes an internal gear as the first shaft, a carrier as the second shaft that revolves together with the planetary gear, and a sun gear as the third shaft. In this way, usability is improved, such as application of a large starting torque from the generator motor to the engine, and the structure is simplified.

  In a preferred aspect, the first and second one-way clutches are arranged coaxially at the same axial position. As a result, the first and second clutches can be configured very compactly, so that space saving can be achieved.

  In a preferred aspect, the first and second one-way clutches include a medium-diameter cylindrical portion connected to the generator motor, a large-diameter cylindrical portion forming a part of the carrier, and an outer periphery of the medium-diameter cylindrical portion. A first contact / separation member disposed between a surface and an inner peripheral surface of the large-diameter cylindrical portion to contact and separate the medium-diameter cylindrical portion and the large-diameter cylindrical portion; an outer peripheral surface of the sun gear; A second contacting / separating member disposed between an inner peripheral surface of the diameter cylindrical portion and contacting / separating the sun gear and the medium diameter cylindrical portion; Thereby, the first and second one-way clutches can be configured more compactly.

  In a preferred aspect, in the electric travel mode, the brake is released, the internal gear is free-run according to the rotation of the sun gear by the generator motor, the first one-way clutch is disconnected, and the carrier Is stopped by friction. As a result, electric traveling with less loss is possible.

  In a preferred aspect, in the engine start mode, the internal gear is restrained by the brake, and the torque of the generator motor is transmitted in the order of the second one-way clutch, the sun gear, the planetary gear, the carrier, and the engine. Then, the engine is started. This makes it possible to start the engine reliably with a small generator motor.

  In a preferred aspect, in an engine start transient mode that is a predetermined engine speed increase period after engine start, the internal gear is restrained by the brake, and the engine and the power generator are disconnected by disengaging the second one-way clutch. Torque exchange between the motor and the axle system is prohibited. As a result, the engine speed can be rapidly increased to a level at which continuous rotation is possible.

  In a preferred aspect, the brake is released when torque is transmitted from the engine to the generator motor and the axle system in a state where the engine speed is equal to or higher than a predetermined value. As a result, the brake operating power can be saved, and the planetary gear mechanism is not worn.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiments, and the technical idea of the present invention may be realized by a combination of other known techniques.

(overall structure)
The apparatus configuration of the hybrid vehicle of this embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing a power transmission system of the hybrid vehicle of this embodiment.

  This hybrid vehicle has an engine 1, a torque transmission control mechanism 2, a generator motor (MG) 3, and an axle system 4.

  The engine 1, the generator motor (MG) 3 and the axle system 4 are not changed from the conventional ones already described and are already well known, and thus the description thereof is omitted. However, the axle system 4 referred to in this embodiment includes at least a transmission 5 and wheels 6 through which the traveling torque is transmitted from the engine 1 and the generator motor (MG) 3. It goes without saying that the transmission 5 may include torque contact / separation means such as a clutch and other gear mechanisms.

  An output shaft of the engine 1 is sequentially connected to a generator motor (MG) 3 and a transmission 5 through a torque transmission control mechanism 2. The torque transmission control mechanism 2 to be described later has a function of changing a torque transmission / reception state between the engine 1, the generator motor (MG) 3 and the transmission 5.

(Torque transmission control mechanism 2)
The torque transmission control mechanism 2 includes a planetary gear mechanism 7, a brake 8, a first one-way clutch 10, and a second one-way clutch 11. The planetary gear mechanism 7 includes a sun gear 71, a carrier 72 that revolves while holding the planetary gear so as to rotate freely, and an internal gear 73. In this embodiment, the sun gear 71 is the first shaft of the planetary gear mechanism 7 referred to in the present invention, the carrier 72 is the second shaft referred to in the present invention, and the internal gear 73 is the third shaft of the planetary gear mechanism 7 referred to in the present invention. It constitutes an axis. The relationship between each axis of the planetary gear mechanism 7 and the first to third axes referred to in the present invention may be other combinations. Since the planetary gear mechanism 7 itself is well known, detailed description thereof is omitted.

  The sun gear 71 is connected to the rotating shaft of the generator motor (MG) 3 through the second one-way clutch 11 for transmitting the torque of the generator motor (MG) 3 to the engine 1.

  The carrier 72 is directly connected to the output shaft (for example, crankshaft) 20 of the engine 1. The carrier 72 is connected to the rotary shaft 30 of the generator motor (MG) 3 through the first one-way clutch 10. Thus, the engine torque is transmitted to the generator motor (MG) 3 and the transmission 5 when the first one-way clutch 10 is in the connected state.

  The internal gear 73 is connected to the brake 8. The brake 8 is fixed to the housing 9, and when the brake 8 is in a restrained state, the rotation of the internal gear 73 is prohibited. That is, the brake 8 is provided in the housing 9 and performs an operation of restraining the internal gear 73 of the planetary gear mechanism 7 or releasing the restraint. This restraint and restraint release are performed by actuating the brake 8 by operating the brake 8, for example, by actuating the brake 8 or by stopping the operation. Since such a brake itself is well known, further explanation is omitted.

(Double clutch 12)
Next, the double clutch 12 including the first one-way clutch 10 and the second one-way clutch 11 will be described with reference to FIG. 2A is a schematic radial side view of the double clutch 12, and FIG. 2B is a schematic axial sectional view of the double clutch 12.

  The double clutch 12 includes a first one-way clutch 10 and a second one-way clutch 11 that are coaxially arranged at the same position in the axial direction. That is, the first one-way clutch 10 is disposed on the radially outer side of the second one-way clutch 11.

  The first one-way clutch 10 is disposed coaxially with the cylindrical medium-diameter cylindrical portion 300 that forms the front end of the rotary shaft 30 of the generator motor (MG) 3 and the medium-diameter cylindrical portion 300 that forms part of the carrier. And a large number of pieces (first contact / separation members) 100 disposed between the outer peripheral surface of the medium diameter cylindrical portion 300 and the inner peripheral surface of the large diameter cylindrical portion 301. The top 100 is locked to and connected to both the medium-diameter cylindrical portion 300 and the large-diameter cylindrical portion 301, and the medium-diameter cylindrical portion 300, the large-diameter cylindrical portion 301, Disconnect the.

  The top 100 is moved in one direction by relative rotation between the large diameter cylindrical portion 301 of the carrier 72 and the medium diameter cylindrical portion 300 forming a part of the rotating shaft 30 of the generator motor (MG) 3 in the initial stage of torque transmission. It is urged and rotated so as to rotate, and as a result, is locked to both the large-diameter cylindrical portion 301 and the medium-diameter cylindrical portion 300. Thereby, the carrier 72 is connected to the generator motor (MG) 3, and the engine torque is transmitted to the generator motor (MG) 3. When the speed relationship between the large-diameter cylindrical portion 301 and the medium-diameter cylindrical portion 300 is reversed, the frame 100 rotates in the reverse direction, and the connection between the large-diameter cylindrical portion 301 and the medium-diameter cylindrical portion 300 through the frame 100 is performed. Is released, whereby the first one-way clutch 10 enters a free-running state.

  The second one-way clutch 11 includes a cylindrical medium-diameter cylindrical portion 300 that forms the front end portion of the rotating shaft 30 of the generator motor (MG) 3 and a rear end portion of the sun gear 71 that is coaxially disposed on the medium-diameter cylindrical portion 300. And disposed between the outer peripheral surface of the sun gear 71 and the inner peripheral surface of the medium-diameter cylindrical portion 300, locked to both the medium-diameter cylindrical portion 300 and the sun gear 71, and connected to each other. And a top (second contact / separation member) 110 that releases the connection between the medium-diameter cylindrical portion 300 and the sun gear 71 by releasing the lock. The top 110 is urged and rotated so as to rotate in one direction by relative rotation between the medium diameter cylindrical portion 300 and the sun gear 71 in the initial stage of torque transmission. As a result, the sun gear 71 and the medium diameter cylinder are rotated. It is locked to both the part 300. Thereby, the rotating shaft 30 of the generator motor (MG) 3 is coupled to the sun gear 71 through the medium diameter cylindrical portion 300 and the top 110. Torque of the generator motor (MG) 3 is transmitted to the sun gear 71. When the speed relationship between the medium-diameter cylindrical portion 300 and the sun gear 71 is reversed, the top 110 rotates in the reverse direction, and the connection through the top 110 between the medium-diameter cylindrical portion 300 and the sun gear 71 is released. 2 one-way clutch 11 is in a free-running state.

  Since the operation principle of the one-way clutch using the pieces 100 and 110 that rotate as described above is well known, further explanation is omitted. In addition, as a one-way clutch, other known types such as a well-known one-way clutch structure that is supported on one side of a rotating body and spring-biased on the other side of the rotating body instead of a rotating piece that rotates automatically. There is no problem even if a one-way clutch is adopted.

(Description of operation)
Next, various torque transmission operations using the torque transmission control mechanism 2 will be described with reference to FIGS. 3 to 7, (A) is a block diagram showing a torque transmission state, and the torque transmission path is shown by a bold line. (B) is a schematic explanatory diagram illustrating the internal torque state of the planetary gear mechanism 7 by arrows. (C) is a schematic explanatory view showing the torque relationship among the sun gear 71, the engine 1, and the brake 8.

(Electric travel mode)
First, the electric travel mode will be described with reference to FIG.

  Since the brake 8 does not prohibit the rotation of the internal gear 73, when the generator motor (MG) 3 rotates the sun gear 71 through the second one-way clutch 11, the planetary gear rotates, and the internal gear 73 rotates accordingly. Rotate. As a result, the carrier 72 does not rotate, and the torque of the generator motor (MG) 3 is not transmitted to the engine 1. Since the carrier 72 does not rotate (the planetary gear does not revolve), the first one-way clutch 10 is in a free-run state.

(Engine start mode)
Next, the engine start mode will be described with reference to FIG.

  Since the brake 8 prohibits the rotation of the internal gear 73, when the generator motor (MG) 3 rotates the sun gear 71 through the second one-way clutch 11, the planetary gear rotates and revolves, and the revolving torque of the planetary gear. Is transmitted to the engine 1 through the carrier 72, and the engine 1 is started. Torque multiplied by the rotational speed ratio between the sun gear 71 and the carrier 72 is transmitted to the engine 1. Of course, the first one-way clutch 10 remains disengaged.

(Engine start transient mode)
Next, the engine start transient mode will be described with reference to FIG.

  In the engine start mode shown in FIG. 4, when the rotation speed of the carrier 72 increases due to the increase in the rotation speed of the engine 1, the rotation of the sun gear 71 increases because the brake 8 prohibits the rotation of the internal gear 73. . When the rotational speed of the sun gear 71 exceeds the rotational speed (MGrpm) of the generator motor (MG) 3, the second one-way clutch 11 is disengaged, so that the engine 1 has not yet reached a sufficient rotational speed. Transmission of torque to the electric motor (MG) 3 and the axle system 4 is prevented. At this stage, the first one-way clutch 10 is still in a disconnected state.

(Engine drive mode)
Next, the engine drive mode will be described with reference to FIG.

  Thereafter, when the rotation speed of the engine 1 further increases and the rotation speed of the carrier 72 further increases, the rotation speed of the carrier 72 (rotation speed of the engine 1) exceeds the rotation speed (MGrpm) of the generator motor (MG) 3. Since the first one-way clutch 10 is in the connected state, the torque of the engine 1 is transmitted to the generator motor (MG) 3 and the axle system 4 through the carrier 72 and the first one-way clutch 10.

  At this time, since the brake 8 prohibits the rotation of the internal gear 73, the rotation speed of the sun gear 71 becomes higher than the rotation speed of the generator motor (MG) 3, and the second one-way clutch 11 is disconnected. Yes.

(Brake release engine drive mode)
Next, the brake release engine drive mode will be described with reference to FIG.

  Thereafter, the restraint of the internal gear 73 by the brake 8 is released. In this state, since both the internal gear 73 and the sun gear 71 can be free-runned, the sun gear 71 and the internal gear 73 have the same rotational speed as the carrier 72 due to friction, and as a result, the planetary gear rotates. There is no. Eventually, when the brake 8 is released, the two shafts of the planetary gear mechanism 7 are in a freely rotating state, so that all the torque of the engine 1 is transmitted to the generator motor (MG) 3 and the axle system 4. For this reason, the planetary gear mechanism 7 is not worn.

(Modification)
One or both of the first one-way clutch 10 and the second one-way clutch 11 used in the above embodiment may be changed to a clutch that can be controlled to open and close.

(Example effect)
According to this embodiment, the engine can be started by the deceleration / multiplication torque when the vehicle is stopped and during EV traveling. Further, torque assist can be performed by the generator motor (MG) 3 during engine startup. Further, the braking energy of the axle system 4 can be regenerated by the generator motor (MG) 3 by stopping the engine and disconnecting it from the generator motor (MG) 3 and the axle system 4. Moreover, it can drive | work in the maximum efficiency area | region of the generator motor (MG) 3 at the time of electric drive. Even if a simple manual transmission is used as the transmission, the input / output rotational speeds can be synchronized without using a friction clutch.

It is a block diagram which shows the power transmission system of the hybrid vehicle of embodiment. It is a figure which shows a coaxial double clutch. FIG. 2A is a schematic radial side view of the double clutch, and FIG. 2B is a schematic axial sectional view of the double clutch 12. It is a figure which shows an electric travel mode. FIG. 3A is a block diagram showing a torque transmission state, and the torque transmission path is shown by a bold line. FIG. 3B is a schematic explanatory diagram illustrating the internal torque state of the planetary gear mechanism 7 with arrows. FIG. 3C is a schematic explanatory view showing a torque relationship among the sun gear, the engine, and the brake. It is a figure which shows an engine starting mode. FIG. 4A is a block diagram showing a torque transmission state, and the torque transmission path is shown by a bold line. FIG. 4B is a schematic explanatory diagram illustrating the internal torque state of the planetary gear mechanism 7 with arrows. FIG. 4C is a schematic explanatory diagram showing the torque relationship among the sun gear, the engine, and the brake. It is a figure which shows an engine starting transient mode. FIG. 5A is a block diagram showing a torque transmission state, and the torque transmission path is shown by a bold line. FIG. 5B is a schematic explanatory diagram illustrating the internal torque state of the planetary gear mechanism 7 with arrows. FIG. 5C is a schematic explanatory diagram showing a torque relationship among the sun gear, the engine, and the brake. It is a figure which shows an engine drive mode. FIG. 6A is a block diagram showing a torque transmission state, and the torque transmission path is shown by a bold line. FIG. 6B is a schematic explanatory diagram illustrating the internal torque state of the planetary gear mechanism 7 with arrows. FIG. 6C is a schematic explanatory diagram showing the torque relationship among the sun gear, the engine, and the brake. It is a figure which shows a brake release engine drive mode. FIG. 7A is a block diagram showing a torque transmission state, and the torque transmission path is shown by a bold line. FIG. 7B is a schematic explanatory diagram illustrating the internal torque state of the planetary gear mechanism 7 with arrows. FIG. 7C is a schematic explanatory diagram showing the torque relationship among the sun gear, the engine, and the brake.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Torque transmission control mechanism 3 Generator motor 4 Axle system 5 Transmission 6 Wheel 7 Planetary gear mechanism 8 Brake 9 Housing 10 First one-way clutch 11 Second one-way clutch 12 Double clutch 30 Rotating shaft 71 Sun gear 72 Carrier 73 Internal gear 100, 110 One-way clutch piece (contact / separation member)
300 Medium diameter cylindrical part 301 Large diameter cylindrical part

Claims (8)

In a hybrid vehicle equipped with an engine, a torque transmission control mechanism, a generator motor and an axle system that are arranged so as to be sequentially connectable,
The torque transmission control mechanism includes a planetary gear mechanism having first, second, and third shafts, a first one-way clutch for transmitting torque of the engine to the generator motor and an axle system, and the generator motor. A second one-way clutch that transmits the torque of the engine to the engine, and a brake,
The brake is provided in a housing and restrains the first shaft of the planetary gear mechanism,
The engine is coupled to a second shaft of the planetary gear mechanism;
The first one-way clutch is disposed between the second shaft of the planetary gear mechanism and the generator motor and the axle system;
The hybrid vehicle according to claim 1, wherein the second one-way clutch is disposed between the generator motor and the axle system and a third shaft of the planetary gear mechanism. The hybrid vehicle according to claim 1,
The planetary gear mechanism is a hybrid vehicle having an internal gear as the first shaft, a carrier as the second shaft that revolves together with the planetary gear, and a sun gear as the third shaft. The hybrid vehicle according to claim 2,
The first and second one-way clutches are hybrid vehicles arranged coaxially at the same axial position. The hybrid vehicle according to claim 3,
The first and second one-way clutches are:
A medium-diameter cylindrical portion connected to the generator motor;
A large diameter cylindrical portion forming part of the carrier;
A first contact / separation member disposed between an outer peripheral surface of the medium diameter cylindrical portion and an inner peripheral surface of the large diameter cylindrical portion and contacting and separating the medium diameter cylindrical portion and the large diameter cylindrical portion;
A second contact / separation member disposed between the outer peripheral surface of the sun gear and the inner peripheral surface of the medium-diameter cylindrical portion to contact and separate the sun gear and the medium-diameter cylindrical portion;
Hybrid car with The hybrid vehicle according to claim 2,
In the electric travel mode, the brake is released, the internal gear is free-run according to the rotation of the sun gear by the generator motor, the first one-way clutch is disconnected, and the carrier is stopped by friction. Hybrid car. The hybrid vehicle according to claim 2,
In the engine start mode, the internal gear is restrained by the brake, and the torque of the generator motor is transmitted in the order of the second one-way clutch, the sun gear, the planetary gear, the carrier, and the engine. A hybrid vehicle to be started. The hybrid vehicle according to claim 2,
In an engine start transient mode that is a predetermined engine speed increase period after engine start, the internal gear is restrained by the brake, and the engine, the generator motor, and the axle system are disconnected by disengaging the second one-way clutch. Vehicle that prohibits torque transfer between The hybrid vehicle according to claim 2,
A hybrid vehicle that releases the brake when transmitting torque from the engine to the generator motor and the axle system in a state where the engine speed is equal to or greater than a predetermined value.

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