JP2003220842A - Torque transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve efficiency of regenerating energy in a torque transmission in which a motor generator is disposed at a speed change gear side from a fluid type torque transmission and to shorten an axial size of the torque transmission. <P>SOLUTION: The torque transmission 1 transmits a torque from an output shaft 81 of an engine 8 to the speed change gear 9 via a transmission shaft 91. The torque transmission 1 comprises a fluid coupling 11, and the motor generator 61 for enabling to receive and deliver the torque to the shaft 91. The fluid coupling 11 has an impeller 12 which inputs an output torque of the engine 8, a turbine 13 which is disposed oppositely to the impeller 12 to output the torque to the shaft 91, and a lock-up unit 14. The turbine 13 is mounted on the shaft 91 via a one-way clutch 16 so as to be relatively rotatable only in the opposite rotating direction of the shaft 91. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque transmission device for transmitting output torque of an engine to a transmission.

[0002]

2. Description of the Related Art Recently, one of the technologies for improving the fuel efficiency of automobiles
As an example, the motor generator is arranged in a torque transmission system for transmitting the output torque of the engine to the transmission to perform regeneration for taking out kinetic energy during traveling as electricity, or to generate electricity charged in the battery by the motor generator. Techniques such as assisting the engine torque by converting into rotation and inputting to the transmission have been proposed.

As a structure of such a torque transmission system, there is one in which a motor generator is arranged between an engine and a fluid type torque transmission device such as a torque converter. This hydraulic torque transmission device includes an impeller to which the output torque of the engine is input, and a turbine that is arranged to face the impeller and outputs the torque to the transmission. In the configuration of this torque transmission system, since the torque from the transmission side is transmitted to the motor generator via the fluid torque transmission device during braking regeneration, the amount of energy in the motor generator is reduced by the amount of braking in the fluid torque transmission device. The amount of regeneration will decrease.

On the other hand, for example, Japanese Patent Laid-Open No. 2000-1
79977 and Japanese Patent Laid-Open No. 2000-287
As in the technique described in Japanese Patent No. 303, there is one having a configuration in which a fluid type torque transmission device is arranged between an engine and a motor generator. In such a configuration, since the motor generator is arranged closer to the transmission than the hydraulic torque transmission device, the torque from the transmission is directly transmitted to the motor generator even during braking regeneration. This facilitates energy regeneration in the motor generator. That is, the energy regeneration amount in this configuration becomes larger than the energy regeneration amount in the configuration in which the motor generator is arranged between the engine and the fluid torque transmission device.

[0005]

However, even in the configuration of the above torque transmission system, some of the torque from the transmission side is transmitted from the transmission to the fluid type torque transmission device, so that the motor generator is used. Not regenerated. Therefore, it is desirable to further improve the efficiency of energy regeneration.

Further, in the structure of this torque transmission system, since the motor generator is arranged between the fluid type torque transmission device and the transmission, the motor generator is arranged between the engine and the fluid type torque transmission device. The axial dimension tends to be larger than the configuration. Therefore, it is also necessary to reduce the axial dimension. An object of the present invention is to improve the efficiency of energy regeneration in the configuration of the torque transmission system in which the motor generator is arranged closer to the transmission than the hydraulic torque transmission device. Another problem is to reduce the axial dimension of the torque transmission system.

[0007]

A torque transmission device according to claim 1 is a torque transmission device for transmitting an output torque of an engine to a transmission, and a transmission shaft for outputting torque to the transmission. It is provided with a fluid type torque transmission device and a motor generator capable of exchanging torque with the transmission shaft. The hydraulic torque transmission device includes an impeller to which the output torque of the engine is input, and a turbine that is arranged to face the impeller and outputs the torque to a transmission shaft. The motor generator has a rotor mounted on the transmission shaft and a stator arranged to face the rotor. The turbine is mounted on the transmission shaft so as to be rotatable only in the opposite rotation direction of the transmission shaft.

In this torque transmission device, the turbine of the fluid type torque transmission device is mounted on the transmission shaft so as to be relatively rotatable only in the counter-rotational direction of the transmission shaft. When the number is relatively higher than the rotation speed of the transmission shaft of the transmission, the turbine and the transmission shaft rotate together and torque is transmitted from the turbine to the transmission shaft. On the contrary, when the rotation speed of the turbine is relatively lower than the rotation speed of the transmission shaft, the turbine relatively rotates in the direction opposite to the rotation direction of the transmission shaft, and torque is not transmitted from the transmission shaft to the hydraulic torque transmission device. It is like this.
As a result, it is possible to suppress the braking due to the torque absorbed by the engine portion via the fluid torque transmission device and improve the efficiency of energy regeneration by the motor generator.

According to a second aspect of the present invention, in the first aspect, the turbine is mounted on the transmission shaft via a one-way clutch. A torque transmission device according to a third aspect is the torque transmission device according to the first or second aspect, further comprising a lockup device for transmitting the output torque of the engine to the transmission shaft without passing through the impeller and the turbine. ing.

In this torque transmission device, when the lockup device is operated, the front cover which constitutes the fluid type torque transmission device, the damper mechanism which constitutes the lockup device, and the rotor of the motor generator are arranged on the transmission shaft. It will be arranged in series. In this configuration, since there is a rotor having a large moment of inertia on the downstream side of the damper mechanism of the lockup device, a vibration system similar to the vibration system in which the damper mechanism is arranged between two flywheels is formed. As a result, the resonance point of the torque transmission system is shifted to the low rotation speed side, and the transmission of the fluctuation of the engine rotation speed to the transmission shaft can be attenuated.

According to a fourth aspect of the present invention, there is provided the torque transmission device according to the third aspect, wherein the lockup device is a separate chamber type operated by a hydraulic pressure supplied from a hydraulic fluid system different from a hydraulic fluid system of the impeller and the turbine. It is equipped with a clutch mechanism. Since this torque transmission device is provided with the separate-chamber clutch mechanism, the responsiveness of the lockup operation is improved. Here, the separate-chamber clutch mechanism is operated by the hydraulic pressure of a hydraulic oil system different from the hydraulic oil system of the impeller and the turbine, and has a structure in which the hydraulic oil on the impeller and turbine side is less likely to be affected by the operation of the clutch mechanism. It is a thing.

A torque transmission device according to a fifth aspect is a torque transmission device for transmitting an output torque of an engine to a transmission, the transmission shaft outputting torque to the transmission, a fluid coupling, and a transmission. And a motor generator capable of exchanging torque with the shaft. The fluid coupling has an impeller to which the output torque of the engine is input, and a turbine that is arranged to face the impeller and outputs the torque to a transmission shaft. The motor generator has a rotor mounted on the transmission shaft between the fluid coupling and the transmission, and a stator arranged to face the rotor.

In this torque transmission device, in the torque transmission system in which the motor generator is arranged closer to the transmission than the fluid type torque transmission device, a fluid coupling is used as the fluid type torque transmission device. Can be shortened. Further, since the fluid coupling has a simple structure, the cost can be reduced. The torque transmission device according to claim 6 is the torque transmission device according to claim 5,
The impeller and turbine form a torus. The torus has a dimension L in the axial direction with respect to a dimension H in the radial direction.
The flatness L / H, which is the ratio, is 0.7 or less.

In this torque transmission device, since the fluid coupling having the flatness of the torus of 0.7 or less is used, the axial dimension can be further shortened.

[0015]

1 is a schematic diagram of a torque transmission device 1 according to an embodiment of the present invention. [Structure] The torque transmission device 1 shown in FIG. 1 is arranged between the output shaft 81 of the engine 8 and the transmission 9.

The engine 8 is an internal combustion engine for burning gasoline or the like to obtain power, and the torque output from the crankshaft (not shown) of the engine 8 is passed through the engine output shaft 81 to the side surface of the engine 8. It is output to the torque transmission device 1 mounted on. The transmission 9 is an automatic transmission or a continuously variable transmission, and receives the torque output from the torque transmission device 1.

The torque transmission device 1 is a device for transmitting the torque from the output shaft 81 of the engine 8 to the transmission 9 via the transmission shaft 91, and is a fluid coupling which is one form of a fluid type torque transmission device. 11 and a motor generator 61 capable of exchanging torque between the transmission shaft 91. The fluid coupling 11 includes an impeller 12 to which the output torque of the engine 8 is input, a turbine 13 arranged to face the impeller 12 to output torque to a transmission shaft 91, and a lockup device 14.

Details of the torque transmission device 1 will be described below with reference to FIG. FIG. 2 is a schematic vertical cross-sectional view of the torque transmission device 1 which embodies the schematic diagram of the torque transmission device 1 shown in FIG. An engine 8 (not shown) is arranged on the left side of FIG. 2, and a transmission 9 (not shown) is arranged on the right side of FIG. Further, OO shown in FIG. 2 is a rotation shaft of the fluid coupling 11 and the motor generator 61.

(A) Fluid Coupling The fluid coupling 11 is mainly a torus 20 composed of an impeller 12 and a turbine 13 which are two types of impellers.
And a lock-up device 14. The front cover 15 is
It is a disk-shaped member and is arranged closest to the engine 8 in the axial direction. A center boss 22 is fixed to the inner peripheral portion of the front cover 15 by welding. The center boss 22 is a cylindrical member that extends in the axial direction, and is inserted into the center hole of a crankshaft (not shown). The center boss 22 has a flange portion 22a extending toward the outer peripheral side on the axial transmission 9 side. A plurality of bolts 23 are fixed to the outer peripheral surface of the front cover 15 on the engine 8 side. For example, the outer peripheral portion of a flexible plate (not shown) is fixed by the bolts 23.
An outer peripheral tubular portion 15 a extending toward the transmission 9 in the axial direction is formed on the outer peripheral portion of the front cover 15. A plurality of teeth 15 extending in the axial direction are formed on the inner peripheral surface of the outer peripheral tubular portion 15a.
b are formed side by side in the circumferential direction. Further, the impeller 12 is attached to the tip of the outer peripheral tubular portion 15a on the axial transmission 9 side.
The outer peripheral edge of the impeller shell 12a is fixed by welding. As a result, the front cover 15, the outer peripheral tubular portion 15a, and the impeller 12 form a fluid working chamber filled with working oil.

The impeller 12 has an output shaft 81 of the engine 8.
It is integrated with the front cover 15 fixed to the.
Then, it is rotatable with respect to the transmission shaft 91 via a bearing 92 and a guide ring 93. Impeller 12
Is a member mainly fixed integrally to the front cover 15, and includes an impeller shell 12a and a plurality of impeller blades 1 fixed inside the impeller shell 12a.
2b and the impeller hub 12c which supports the inner peripheral part of the impeller shell 12a.

The turbine 13 is arranged so as to face the impeller 12, and is a member for transmitting the torque input to the impeller 12 by the flow of hydraulic oil and outputting it to the transmission shaft 91. The turbine 13 is attached to the transmission shaft 91 via the one-way clutch 16 so that the turbine 13 can relatively rotate only in the counter-rotational direction of the transmission shaft 91. That is, when the rotation speed of the turbine 13 of the fluid coupling 11 is higher than the rotation speed of the transmission shaft 91, the turbine 13 and the transmission shaft 91 rotate integrally, and torque is transmitted from the turbine 13 to the transmission shaft 91. To do. On the contrary, when the rotation speed of the turbine 13 is lower than the rotation speed of the transmission shaft 91, the turbine 13 relatively rotates in a direction opposite to the rotation direction of the transmission shaft 91, and torque is not transmitted from the transmission shaft 91 to the turbine 13. It has become.

The turbine 13 is mainly composed of the turbine shell 1
3a, a plurality of turbine blades 13b fixed to a surface of the turbine shell 13a on the impeller 12 side, and a turbine carrier 13c for supporting the turbine shell 13a.
It consists of and. The inner peripheral portion of the turbine shell 13a is fixed to the outer peripheral portion of the turbine carrier 13c by a plurality of rivets 24. Turbine carrier 13c
The inner peripheral part of the above is spline-engaged with the transmission shaft 91 of the transmission through the one-way clutch 16. The surface of the turbine carrier 13c on the impeller 12 side and the impeller hub 12
A first thrust bearing 28 is arranged axially with respect to c. The first thrust bearing 28 is formed with a plurality of grooves penetrating in the radial direction. Further, on the engine 8 side of the turbine carrier 13c, a thrust surface slidable on the surface of the driven plate 40, which will be described later, that constitutes the lockup device 14 on the turbine 13 side is attached.

As a result, the impeller 12 and the turbine 13 are
A torus 20 is formed by and. In this embodiment, the torus 20 has a small flatness. Specifically, as shown in FIG. 3, a torus 20 having a flatness L / H of 0.7 or less, which is a ratio of the radial dimension H and the axial dimension L, is used. Here, the radial dimension H refers to the distance between the innermost radial portion and the radially outer portion inside the impeller 12, and the axial dimension L refers to the axial transmission 9 inside the impeller 12. Side portion and a portion inside the turbine 13 on the axial engine 8 side.

Next, the lockup device 14 will be described. The lockup device 14 is a device for mechanically connecting the front cover 15 and the transmission shaft 91 to each other as needed for operation. The lockup device 14 includes a clutch mechanism 17 that is operated by the hydraulic pressure of hydraulic oil, and a damper mechanism 18 that absorbs torsional vibration when the clutch mechanism 17 and the front cover 15 are connected.

The clutch mechanism 17 includes a front cover 15
Is a mechanism for directly transmitting torque from the turbine to the turbine 13. The clutch mechanism 17 mainly includes the outer peripheral tubular portion 15 a of the front cover 15 and the damper mechanism 18.
Of the first drive plate 31, the clutch plates 32, 33 and 34, and the piston 35. The clutch plates 32 and 34 have outer peripheral teeth on their outer peripheral edges that engage with the teeth 15b of the outer peripheral tubular portion 15a. As a result, the clutch plates 32 and 34 are
The front cover 15 and the front cover 15 rotate together and are axially movable relative to each other.

The clutch plate 33 is arranged axially between the clutch plate 32 and the clutch plate 34. A plurality of teeth are formed on the inner peripheral edge of the clutch plate 33. Further, friction facings are attached to both axial surfaces of the clutch plate 33. A pair of first
An annular second drive plate 37 is sandwiched between the outer peripheral portions of the drive plates 31 in the axial direction. The second drive plate 37 has a plurality of teeth arranged side by side in the circumferential direction, and is fixed to the pair of first drive plates 31 by a plurality of rivets 39. The teeth of the clutch plate 33 are engaged with the teeth of the first drive plate 31. As a result, the clutch plate 33 is configured to rotate integrally with the drive plates 31 and 37 and relatively move in the axial direction. Axial transmission 9 on the inner peripheral edge of the outer peripheral tubular portion 15a
A snap ring 36 is attached to the side. The snap ring 36 is a member for limiting the movement of the clutch plate 34 or the like toward the transmission 9 in the axial direction.

The piston 35 is an annular member. The piston 35 is arranged near the axial transmission 9 side of the front cover 15. The outer peripheral surface of the piston 35 abuts on the inner peripheral surface formed on the outer peripheral side of the front cover 15, is supported in the radial direction, and is relatively movable in the axial direction and the rotational direction. An annular seal member is attached to the outer peripheral surface of the piston 35. The seal member is in contact with the inner peripheral surface and blocks the flow of the hydraulic oil between both sides in the axial direction. The inner peripheral surface of the piston 35 is in contact with the outer peripheral surface of the flange portion 22a of the center boss 22 and is supported so as to be movable in the axial direction. An annular seal member is attached to the outer peripheral surface of the flange portion 22a of the center boss 22. The seal member abuts on the inner peripheral surface of the piston 35 and shuts off the flow of hydraulic oil between both sides in the axial direction of the piston 35. Further, the outer peripheral side portion of the piston 35 is arranged close to the clutch plate 32. The piston 35
It is configured to move in the axial direction by a change in the hydraulic pressure in the hydraulic chamber 21 (separate chamber) formed between the piston 35 and the front cover 15. The hydraulic chamber 21 communicates with an oil hole 91a penetrating the axial center of the transmission shaft 91 via an oil passage 22b formed between the center boss 22 and the front cover 11 in the axial direction.

With the above construction, the hydraulic oil system for operating the clutch mechanism 17 is an independent hydraulic system different from the hydraulic oil system for operating the torus 20. The damper mechanism 18 includes a pair of first drive plates 31, a driven plate 40, and a plurality of torsion springs 38. The first drive plate 31 is an annular member, the outer peripheral portions of which are fixed to each other, and the inner peripheral portions of which are axially spaced. On the inner peripheral side portion of the first drive plate 31, a spring support portion 31 a cut and raised in the axial direction is formed. Between the axial direction of the first drive plate 31,
The driven plate 40 is arranged. A hub portion 40a is formed on the inner peripheral portion of the driven plate 40 and is spline-engaged with the transmission shaft 91. An annular thrust washer 27 is arranged between the center boss 22 and the hub portion 40a in the axial direction. In the outer peripheral portion of the driven plate 40, the spring support portion 31
A window 40b is formed in the portion corresponding to a.
The torsion spring 38 is a member arranged in the window hole 40b and in the spring support portion 31a, and the transmission shaft 9 from the first drive plate 31 via the driven plate 40.
1 is a member for transmitting torque to 1 and absorbing / damping torsional vibration. The torsion spring 38 is a coil spring that extends in an arc or linear shape in the circumferential direction. Both ends of the torsion spring 38 in the circumferential direction are supported by both ends of the window hole 40b and the spring support portion 31a in the circumferential direction. Further, both sides in the axial direction of the torsion spring 38 are supported by the spring support portions 31a.

The hydraulic oil supplied to the fluid coupling 11 is supplied by an oil pump 19 driven by the rotation of the transmission shaft 91, as shown in FIG. The oil pump 19 is arranged near the coupling portion between the rotor 62 of the motor generator 61 and the transmission shaft 91. (B) Motor Generator The motor generator 61 includes a rotor 62 mounted on the transmission shaft 91 and a stator 6 arranged to face the rotor 62.
3 and 3. The rotor 62 has a rotor magnet made of a permanent magnet on the outer peripheral side. A cylindrical portion 62a extending in the axial direction is formed on the inner peripheral side of the rotor 62. The tubular portion 62a is spline-engaged with the transmission shaft 91 and is rotatable integrally with the transmission shaft 91. The rotor support portion 4 is provided on the surface of the converter cover 3 that covers the torque transmission device 1 on the transmission 9 side, and the outer peripheral portion of the tubular portion 62 a is rotatably supported via the bearing 94. is doing. The stator 63 is a member wound with a coil arranged on the outermost peripheral side of the torque transmission device 1, is connected to a battery (not shown), and exchanges electricity.

[Operation] Next, the operation of the torque transmission device 1 will be described. FIG. 4 shows the operation mode and the torque transmission device 1.
5 is a table showing the state of each part of FIG. 5, and FIG. 5 is a time chart showing the state of each part of the torque transmission device 1 of FIG.
In FIG. 4, the engine 8, the motor generator 61, the transmission 9, the lockup device 14, the fluid coupling 11 (in the following description, the impeller 12, the turbine 13, and the one-way clutch 16 are shown as the respective parts of the torque transmission device 1 and the like. And a starter (not shown in FIG. 1) for starting the engine 8 are listed as items.
In addition to the items of FIG. 4, FIG. 5 lists the vehicle speed, foot brake, and accelerator. Hereinafter, the operation of the torque transmission device 1 will be described according to the numbers in FIGS. 4 and 5.

(1) During parking (stop) At the time of parking (stop), the engine 8 is off,
The shift position of the transmission 9 is parking (hereinafter, P) or neutral (hereinafter, N), and the starter, the motor generator 61, and the fluid coupling 11 are off.

(2) First-time start When the engine 8 is first started, the starter is turned on to start the engine 8. Here, the engine 8 operates at low speed. The shift position of the transmission 9 is P or N (idling state). (3) Warm-up operation When the engine 8 is started, the fluid coupling 11
Operates in a low torque state and shifts to warm-up operation. At this time, when the battery is insufficiently charged, the motor generator 61 is set to the power generation mode (hereinafter, referred to as G mode),
The torque of the rotor 62 mounted on the transmission shaft 91 is converted into electricity by the electromagnetic action with the stator 63 to charge the battery. On the contrary, when the battery is sufficiently charged or when the charging is completed during the warm-up operation, the engine 8 is stopped and the motor generator 61 and the fluid coupling 11 are turned off.

(4) Change of transmission shift to start and standby for start Next, the shift position of the transmission 9 is changed from the P or N state to the forward (hereinafter referred to as D) state (when going backward, Shift position to R). At this time, the motor generator 61 is set to the discharge mode (hereinafter, referred to as M mode), the electricity charged in the battery is converted into the rotation of the rotor 62, and the torque is input to the transmission shaft 91. This causes the motor generator 61 to generate a creep state (hereinafter, referred to as engine creep) that is normally generated by the torque from the engine (hereinafter, referred to as motor creep). Thus, for example, when the brake is released from the scene where the vehicle is stepped on and the brake is released, acceleration that drives the vehicle can be generated from that moment, and the controlled vehicle is given an unpleasant feeling due to a response delay that is likely to occur. It can be avoided.

(5) Start Next, the accelerator is depressed to start. At this time, the engine 8 starts in the off state. That is, the vehicle is driven only by the motor generator 61. Then, according to the accelerator depression amount, the motor generator 61
The torque input to the transmission shaft 91 from increases, and the vehicle speed gradually increases. As a result, a smooth start can be obtained.

(6) Restart of engine Next, when the number of revolutions reaches, for example, 400 to 500 min ^-1 , the lockup device 14 is operated (hereinafter referred to as lockup ON) to output the output shaft of the engine 8. 81 is directly connected to the transmission shaft 91, and the engine 8 is restarted. When the engine 8 is restarted, the lockup device 14 is turned off so that the output torque of the engine 8 is transmitted to the transmission shaft 91 via the fluid coupling 11. As a result, the vehicle is driven by the torque of the engine 8 and the motor generator 61. The lockup device 14 is, as shown in FIG.
Since the separate chamber type clutch mechanism 17 having the hydraulic chamber 21 different from the fluid working chamber in which the turbine 13 and the impeller 12 operate is provided, the lockup operation is performed with good response even in the above temporary operation. be able to.

(7) After the acceleration engine 8 is restarted, as described above, the transmission shaft 91
The torque transmitted to the engine is a total value of the output torque of the engine 8 and the output torque of the motor generator 61 transmitted via the fluid coupling 11. Then, by further depressing the accelerator, the torque from the engine 8 increases and the motor generator 61
The input torque from is relatively small, and the drive is switched to drive by the engine 8. In addition, when the charge amount of the battery becomes insufficient, the motor generator 61 is timely set to G
The battery is charged as a mode.

(8) Low speed running After being accelerated to some extent, the vehicle runs at low speed. At this time, as in the case of acceleration, the motor generator 61 is turned off or in the G mode. (9) Gear shifting Next, the vehicle shifts while shifting the shift position of the transmission 9 as appropriate. At this time, the motor generator 61 is connected to the transmission shaft 9
Synchronous control of the rotation speed of 1 is performed. Specifically, when the transmission 9 is downshifted, the motor generator 61 is set to M
In this mode, the rotation speed of the transmission shaft 91 is increased to synchronize the rotation speeds of the engine 8 and the transmission shaft 91, and then the shift change is performed. On the contrary, at the time of up-shift, the motor generator 61 is set to the G mode, the rotation speed of the transmission shaft 91 is lowered to synchronize the rotation speeds of the engine 8 and the transmission shaft 91, and then the shift change is performed. As a result, shock during gear shifting can be reduced.

(10) High-speed traveling Next, when the vehicle speed rises, the lockup device 14 is operated with the lockup on. At this time, if the battery is insufficiently charged, the motor generator is set to the G mode and the torque from the engine 8 is regenerated to charge the battery. (11) Loose accelerator during traveling When the vehicle is traveling, the accelerator may be stepped down to lower the speed slightly. At this time, the lockup device 14 is locked up and off, and at the same time, the motor generator 61 is set to the G mode to regenerate the torque of the transmission shaft 91. That is, energy regeneration is performed while gently braking the vehicle. At this time, the rotational speed of the engine 8 is slightly lower than the rotational speed of the transmission shaft 91, so that the rotational speed of the transmission shaft 9 is lower than that of the turbine 13 of the fluid coupling 11.
The rotation speed of 1 is higher. However, the turbine 13
By the one-way clutch 16, torque is not transmitted from the transmission shaft 91 to the turbine 13, and braking by the fluid coupling 11 does not occur. As a result, the efficiency of energy regeneration by the motor generator 61 is improved.

(12) When the accelerator is suddenly turned off while the vehicle is traveling, the accelerator may be fully closed to further decelerate the vehicle and the fuel supply to the engine 8 may be stopped (hereinafter referred to as fuel cut). . At this time, the lockup device 14 is turned on to turn on the engine 8
The output shaft 81 and the transmission shaft 91 are directly connected. At this time, the motor generator 61 is kept in the G mode, and the regenerative braking is performed by the motor generator 61 and the engine braking is performed. Since the lockup device 14 is in the lockup ON state, it is easy to restart the engine 8 at the time of reacceleration.

(13) Braking When the foot brake is depressed to perform braking, the engine brake, the regenerative braking by the motor generator 61 and the braking by the foot brake are applied, and the vehicle is rapidly decelerated. (14) Stopping the vehicle When stopping the vehicle, braking is performed by the foot brake to stop the vehicle, and then the shift position is set to N or P. Then, the engine 8, the fluid coupling 11, the lockup device 14, and the motor generator 61 are turned off.

[Characteristics] The characteristics of the torque transmission device of this embodiment will be described. (1) Improvement of regenerative efficiency As described above, the torque transmission device 1 according to the present embodiment.
Then, when braking by accelerator off or braking,
Energy regeneration by the motor generator 61 is performed.

By the way, the torque transmission device 1 of the present embodiment
In the turbine 13 of the fluid coupling 11
Is mounted on the transmission shaft 91 so as to be relatively rotatable only in the counter-rotational direction of the transmission shaft 91. Therefore, when the rotation speed of the turbine 13 is higher than the rotation speed of the transmission shaft 91,
The turbine 13 and the transmission shaft 91 rotate integrally, and torque is transmitted from the turbine 13 to the transmission shaft 91. vice versa,
When the rotation speed of the turbine 13 is lower than the rotation speed of the transmission shaft 91, the turbine 13 relatively rotates in a direction opposite to the rotation direction of the transmission shaft 91, and torque is not transmitted between the turbine 13 and the transmission shaft 91. It has become. As a result, braking due to the resistance torque that rotates the engine 8 via the fluid coupling 11 can be suppressed, and the efficiency of energy regeneration by the motor generator 61 can be improved. In particular, this is effective when the torque transmission from the engine 8 is performed via the fluid coupling 11, such as when the accelerator is off during running. Also,
It is also possible to suppress heat generation of the hydraulic oil in the fluid coupling 11.

(2) Reduction of axial dimension and cost reduction In the torque transmission device 1 of the present embodiment, in the torque transmission system in which the motor generator 61 is arranged closer to the transmission 9 than the fluid type torque transmission device is, Since the fluid coupling 11 is adopted as the fluid torque transmission device, the axial dimension can be shortened. Further, since the fluid coupling 11 has a simple structure, the cost can be reduced.

(3) Damping effect of transmission of fluctuations in engine speed The torque transmission device 1 according to the present embodiment has the front cover 15 of the fluid coupling 11 in order from the engine 8 to the transmission 9 during lockup. In addition, the shell including the impeller shell, the damper mechanism 18 that configures the lockup device 14, and the rotor 62 of the motor generator 61 are arranged in series on the transmission shaft 91.
At this time, since there is the rotor 62 having a large moment of inertia on the downstream side of the damper mechanism 18, as shown in FIG. 6, a vibration system similar to a vibration system in which the damper mechanism is arranged between so-called two flywheels is generated. Composed. As a result, as shown in FIG. 7, the resonance point of the torsional vibration of the system including the torque transmission device 1 shifts from the resonance point A in the absence of the conventional motor generator to the resonance point B on the low rotation speed side. The transmission of fluctuations in the number of revolutions of the engine 8 can be attenuated.

(4) Improving the feeling by driving only the motor generator at the time of starting Since the torque transmission device 1 of the present embodiment can drive the vehicle only by the torque of the motor generator 61 at the time of starting, the starting of the driver It can contribute to secure a comfortable start feeling without delay in response to the will of the car. Also,
When the accelerator is turned off during traveling only by the motor generator, including during motor creep, the transmission shaft 9
Since the torque of 1 is not transmitted to the fluid coupling 11 by the one-way clutch 16, most of the kinetic energy is directed to regeneration by the motor generator,
The fuel consumption can be saved.

(5) Reduction of shift shock In the torque transmission device 1 of the present embodiment, when the transmission 9 is downshifted, the motor generator 61 is set to the M mode to increase the rotation speed of the transmission shaft 91 to increase the speed of the engine 8. After the rotation speeds of the transmission shaft 91 and the transmission shaft 91 are synchronized, the shift is changed. On the contrary, at the time of up-shift, the motor generator 61 is set to the G mode, the rotation speed of the transmission shaft 91 is lowered to synchronize the rotation speeds of the engine 8 and the transmission shaft 91, and then the shift change is performed. This allows
Gear shift shock can be reduced.

(6) Improving responsiveness of lock-up operation In the torque transmission device 1 of this embodiment, the hydraulic chamber 21 (separate chamber) operable by the hydraulic pressure of the hydraulic oil system different from the hydraulic oil system of the impeller 12 and the turbine 13 is used. ) Is provided, the influence of the flow of hydraulic oil on the side of the impeller 12 and the turbine 13 is reduced, and the response of the lockup operation is improved. Also, the hydraulic chamber 21 is
In order to improve the transmission of hydraulic pressure, the dimension between the front cover 11 and the piston 35 in the axial direction is reduced, which also has the effect of reducing the axial dimension of the entire torque transmission device 1.

[0048]

In the torque transmission device according to the present invention, the turbine of the fluid type torque transmission device and the transmission shaft of the transmission are connected in the structure in which the motor generator is arranged on the transmission side of the fluid type torque transmission device. Is performed via the one-way clutch, the efficiency of energy regeneration during braking can be improved. Further, by adopting a fluid coupling as the fluid type torque transmission device, it is possible to reduce the axial dimension.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a torque transmission device according to an embodiment of the present invention.

FIG. 2 is a schematic vertical sectional view of a torque transmission device.

FIG. 3 is a partial cross-sectional view showing a fluid coupling impeller and a turbine.

FIG. 4 is a table showing operating modes and states of various parts of the torque transmission device.

5 is a time chart showing the state of each part of the torque transmission device of FIG.

FIG. 6 is a schematic diagram showing a vibration system of a torque transmission system during lockup.

FIG. 7 is a diagram for explaining the effect of attenuating the transmission of fluctuations in engine rotation speed during lockup.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 torque transmission device 8 engine 9 transmission 11 fluid coupling (fluid type torque transmission device) 12 impeller 13 turbine 14 lockup device 16 one-way clutch 17 clutch mechanism 61 motor generator 62 rotor 63 stator 91 transmission shaft

Claims (6)

[Claims] 1. A torque transmission device for transmitting an output torque of an engine to a transmission, the transmission shaft outputting the torque to the transmission, an impeller to which the output torque of the engine is input, and the impeller. A hydraulic torque transmission device having a turbine arranged to face the transmission shaft to output torque to the transmission shaft, a rotor mounted on the transmission shaft, and a stator arranged to face the rotor, A motor generator capable of transmitting and receiving torque to and from a transmission shaft, wherein the turbine is mounted on the transmission shaft so as to be relatively rotatable with respect to the transmission shaft only in a counter-rotational direction thereof. Torque transmission device. 2. The torque transmission device according to claim 1, wherein the turbine is mounted on the transmission shaft via a one-way clutch. 3. The hydraulic torque transmission device further comprises a lockup device for transmitting the output torque of the engine to the transmission shaft without passing through the impeller and the turbine. The torque transmission device described in 1. 4. The lock-up device includes a separate-chamber clutch mechanism that is operated by hydraulic pressure supplied from a hydraulic oil system different from the hydraulic oil system of the impeller and the turbine. The torque transmission device according to item 3. 5. A torque transmission device for transmitting an output torque of an engine to a transmission, a transmission shaft outputting the torque to the transmission, an impeller to which the output torque of the engine is input, and the impeller. A fluid coupling having a turbine arranged to face the transmission shaft and outputting a torque to the transmission shaft, and a rotor mounted on the transmission shaft between the fluid coupling and the transmission and facing the rotor. A torque transmission device comprising: a stator arranged; and a motor generator capable of exchanging torque with the transmission shaft. 6. The impeller and the turbine form a torus, wherein the torus has an axial dimension L with respect to a radial dimension H.
The flatness ratio L / H, which is the ratio of the above, is 0.7 or less.
The torque transmission device described in 1.