KR100714908B1 - Torque converter and oil pressure control method for an hybrid electric vehicle - Google Patents

Abstract

The present invention discloses a torque converter for a hybrid vehicle and a hydraulic control method thereof, which are applied to a vehicle which can use an engine and a motor at the same time as a driving source, cut off the driving force of the engine or the motor, and can drive with only one driving source.

The torque converter for a hybrid vehicle of the present invention includes a front cover which rotates according to a driving force of an engine, an impeller coupled to the front cover to rotate together, a turbine disposed facing the impeller, and positioned between the impeller and the turbine. Stator for changing the flow of oil from the impeller side, a lock-up clutch coupled to the turbine can directly transfer the driving force of the engine to the turbine and coupled to one side of the turbine to cut off the power of the engine or transmission It includes an engine power cut clutch transmitted to the input shaft of the.

 Hybrid, torque converter, clutch, power, engine, motor

Description

Torque converter and oil pressure control method for an hybrid electric vehicle

1 is a block diagram showing a state in which an embodiment of the present invention is applied.

FIG. 2 is a half sectional view of the torque converter shown in part A of FIG. 1 to describe an embodiment of the present invention.

3 is a flowchart illustrating a process of transmitting power of an engine in an embodiment of the present invention.

4 is a diagram illustrating an operation of a torque converter according to an embodiment of the present invention.

5 is a view illustrating a state in which the lockup clutch is turned off and the engine power shutoff clutch is turned off according to an embodiment of the present invention.

6 is a view for explaining a state in which the lockup clutch is turned on and the engine power shut-off clutch is turned off according to an embodiment of the present invention.

The present invention relates to a torque converter for a hybrid vehicle and a hydraulic control method thereof, and more particularly, to a vehicle that can simultaneously use an engine and a motor as a driving source, cut off the driving force of the engine or the motor, and can drive with only one driving source. The present invention relates to a torque converter for a hybrid vehicle and a hydraulic control method thereof.

In general, a hybrid vehicle operates not only an engine using gasoline or diesel but also a motor by electric power supply to improve fuel efficiency and reduce environmental pollution. Such hybrid vehicles include a hard type (also referred to as a hard type or a full type) in which a motor or an engine is selected and used as a driving source for driving a vehicle, and the motor is an auxiliary driving source when a large force such as acceleration or climbing is required while the engine is always driven. It can be divided into soft type (soft type, also known as Mild type).

The hard type hybrid vehicle has a configuration in which the engine can be driven only by a motor when the engine is poor in fuel efficiency, that is, when the vehicle starts, and only by the engine when driving normally. have. In addition, when the soft type hybrid vehicle requires a large force such as acceleration or climbing while the engine is always driven, the motor is assisted to drive the vehicle, and the driving force of the motor is cut off. The engine is driven only by the engine. In the state where the motor of such a soft type hybrid vehicle is not driven, charging is performed by the driving force of the engine.

Since the hybrid vehicle of the hard type is driven by the motor or the engine alone, the motor installed in the vehicle must have a sufficiently large capacity. In addition, the soft type hybrid vehicle is always driven using the driving force of the engine, and since the motor is used as a driving source auxiliary, the fuel efficiency improvement effect of the hybrid vehicle may be deteriorated.

Therefore, it is necessary to develop a torque converter that can simultaneously satisfy the advantages of a hard type hybrid vehicle and a soft type hybrid vehicle.

Therefore, the present invention has been proposed to solve the above problems, and an object of the present invention is to use a motor or an engine as an independent driving source, or to use a motor and an engine as a driving source at the same time to satisfy various driving conditions. The present invention provides a torque converter for a hybrid vehicle applied to a vehicle.

In addition, the present invention maintains the running performance of the existing vehicle, while reducing the size of the motor mounted on the hard-type hybrid vehicle, while reducing the vibration of the vehicle and driving by driving the engine in an uphill drive to realize a low fuel consumption To improve the marketability of the vehicle and to provide a torque converter for a hybrid vehicle that satisfies the various design conditions of the vehicle.

In addition, the present invention is to provide a hydraulic control method of a torque converter for a hybrid vehicle to prevent the temperature rise of the engine power shut-off clutch by allowing the fluid circulating in the torque converter to be circulated into the engine power shut-off clutch.

In order to achieve the above object, the present invention, the front cover is rotated by the driving force of the engine, the impeller coupled to the front cover and rotate together, the turbine disposed facing the impeller, located between the impeller and the turbine Stator for changing the flow of oil from the turbine to the impeller side, a lock-up clutch coupled to the turbine can directly transfer the driving force of the engine to the turbine and one side of the turbine coupled to the power of the engine delivered from the turbine A torque converter for a hybrid vehicle including an engine power shut-off clutch that shuts off or transmits the transmission to an input shaft of a transmission.

One side of the engine power cut clutch is coupled to a spline hub which is splined to the input shaft of the transmission.

Preferably, the engine power shut-off clutch is made of a multi-plate clutch.

Preferably, the engine power shut-off clutch is disposed between the front cover and the turbine.

The engine power shutoff clutch may include a first power transmission member coupled to a turbine or a turbine shaft, one or more first friction materials coupled to the first power transmission member, and a second power transmission member coupled to a spline hub splined to a transmission input shaft. And at least one second friction material, the first friction material and the second friction material coupled to the second power transmission member to transmit the driving force of the engine to the spline hub by frictional contact corresponding to the first friction material. It is preferable to include a piston disposed on one side of the first friction material or the second friction material to be in contact with each other or released.

The spline hub is preferably arranged with bearings for smooth rotation in the axial direction between the front cover and the turbine shaft and the corresponding portion.

In addition, the present invention is a front cover that rotates by the driving force of the engine, an impeller coupled to the front cover and rotates together, a turbine disposed facing the impeller, located between the impeller and the turbine of the oil coming out of the turbine Stator for changing the flow to the impeller side, a lock-up clutch coupled to the turbine to directly transfer the driving force of the engine to the turbine, and coupled to one side of the turbine to cut off the power of the engine transmitted from the turbine or to the input shaft of the transmission In the method for hydraulically controlling the lock-up clutch and the engine power shut-off clutch of a hybrid vehicle torque converter including an engine power shut-off clutch for transmitting, the operating pressure at which the engine power cut-off clutch is operated and the engine power cut-off clutch are released. To control the release pressure , Wherein the lock-up clutch operating pressure which is operated and controlled so as to be supplied, there is provided a release pressure of the engine power cut-off clutch is a hydraulic control method of the hybrid vehicle, the torque converter is controlled to act as operating pressure of the lock-up clutch.

When the engine power shutoff clutch is operated and the lockup clutch is operated, the operating pressure of the engine power shutoff clutch is higher than the operating pressure of the lockup clutch, and the operating pressure of the lockup clutch is at a release pressure of the lockup clutch. It is preferable to be controlled high compared with.

When the engine power shutoff clutch is activated and the lockup clutch is released, the operating pressure of the engine power shutoff clutch is higher than the operating pressure of the lockup clutch, and the release pressure of the lockup clutch is equal to the operating pressure of the lockup clutch. It is preferable to be controlled high compared with.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram for explaining an embodiment according to the present invention, showing a power transmission structure of a hybrid vehicle. The hybrid vehicle to which the present invention is applied includes an engine E as a driving source of the vehicle, a torque converter A for transmitting the driving force of the engine E to the transmission T, and a motor M as another driving source of the vehicle. It may include. That is, in the power transmission structure of the hybrid vehicle applied to the present invention, as shown in FIG. 1, the driving force of the engine passes through the transmission T and the driving shaft S via the torque converter A, and the driving wheels TI. Can be delivered. In addition, the driving force of the motor (M) can be transmitted to the drive wheel (TI) through the transmission (T), and the drive shaft (S). In this case, the torque converter A includes an engine power shut-off clutch that connects or blocks power of the engine.

That is, according to the present invention, the driving force of the motor M and the engine E can be simultaneously used as the driving source of the vehicle through the structure in which the clutch which transmits or blocks the power of the engine is included in the torque converter A. The present invention can be used as a drive source of the vehicle by selecting the drive source of any one of the motor (M) or the engine (E). Thus, the structure of the torque converter A of the present invention including the clutch to cut off or connect the power of the engine E will be described in detail with reference to FIG. In addition, in the embodiment of the present invention, the driving force of the engine may be transmitted through the impeller and the turbine to be transmitted to the transmission through the engine power shut-off clutch.

2 is a half sectional view for explaining an embodiment according to the present invention, which shows a torque converter (A). The torque converter A of the present invention includes a front cover 1, an impeller 3, a turbine 5, an engine power shutoff clutch 7, and the like.

The front cover 1 may be connected to the output shaft of the engine E which can rotate by the driving force of the engine E. And the impeller 3 and the turbine 5 are arrange | positioned rotatably about a rotating shaft in the position which mutually faces. The impeller 3 is rotated by the rotation of the front cover 1 and the turbine 5 is rotated while the fluid disposed therein is rotated together by the rotation of the impeller 3 so that the driving force is transmitted. In addition, between the impeller 3 and the turbine 5, a stator 6 for changing the flow of oil from the impeller 3 or the turbine 5 is arranged. The turbine 5 is coupled to the turbine shaft 9 by rivets or the like, and the turbine shaft 9 also rotates with the rotation of the turbine 5. In particular, the turbine shaft 9 is arranged in a structure capable of free rotation on the outer periphery of the transmission input shaft 11. On the other hand, a lockup clutch 13 is coupled to the turbine 5 so that the driving force of the engine can be transmitted directly to the turbine 5 without passing through the impeller 3. The lock-up clutch 13 may be directly in contact with the front cover 1 by hydraulic pressure and directly transmit the driving force of the engine transmitted through the front cover 1 to the turbine 5. The lock-up clutch structure that can be applied to the present invention can be used because the general structure of the detailed description thereof will be omitted.

One side of the engine power cutoff clutch 7 is coupled to the turbine 5 to block the driving force of the engine transmitted from the turbine 5 or transmit it to the input shaft 11 of the transmission. That is, the engine power cutoff clutch 1 may transmit the driving force of the engine transmitted to the turbine 5 to the transmission input shaft 11 through the spline hub 13, and may block the driving force of the engine E. The engine power shutoff clutch 7 includes a first power transmission member 15 coupled to the turbine shaft 9 and a second power transmission member 17 coupled to the spline hub 13. In addition, at least one first friction material 19 and a second friction material 21 which are in friction contact with each other are provided to the first power transmission member 15 and the second power transmission member 17, respectively. In addition, the engine power shut-off clutch 7 includes a piston 23 which is axially moved by hydraulic pressure such that the above-described first friction material 19 and the second friction material 21 are in friction contact with each other or the contact state can be released. Is placed. Of course, the spline hub 13 is splined to the transmission input shaft 11 to transmit the driving force of the engine transmitted through the turbine 5 to the transmission side. Through this structure, the driving force of the engine can be transmitted to the turbine 5 and transmitted or cut off to the transmission depending on the operating or non-operating control state of the engine power shut-off clutch 7. In the spline hub 13, bearings 25 and 27 are disposed between the front cover 1 and the turbine shaft 9, respectively. The spline hub 13 can rotate smoothly while withstanding the force acting in the axial direction by the bearings 25 and 27.

The above-described engine power shut-off clutch 7 is for transmitting or blocking the driving force of the engine to the transmission input shaft 11, and the friction materials of the single plate or the multi-plate are mutually shifted by the piston 23 moving in the axial direction by hydraulic pressure. It has a structure in which friction contact or contact can be released.

This engine power shut-off clutch 1 may be arranged in the space between the turbine 5 and the lockup clutch 13.

On the other hand, the motor (not shown) may be installed in a separate position to transmit the driving force to the transmission.

In addition, the fluid circulating inside the torque converter flows into the engine power shutoff clutch to prevent the temperature rise of the engine power shutoff clutch 7.

The torque converter may be provided with a first port 25 which is an oil channel so that fluid is supplied to act as a release pressure of the engine power shutoff clutch 7 or an operating pressure of the lockup clutch 13. The turbine shaft 9 may also be provided with a second port 9a through which oil acts on the operating pressure of the engine power shut off clutch 7. In addition, the spline hub 13 may be provided with a third port 13a to which oil which acts as a release pressure of the lockup clutch 13 is supplied.

Subsequently, the power transmission path of the torque converter according to the embodiment of the present invention will be described in detail with reference to FIG. 3.

3 is a block diagram showing a power transmission path in which the engine power shut-off clutch 7 is operated in this invention so that the driving force of the engine E is transmitted to the transmission T. As shown in FIG.

First, when the piston 23 of the engine power shutoff clutch 7 moves in the axial direction by the operation of hydraulic pressure, the lockup clutch 13 is engaged in a state in which the first friction material 19 and the second friction material 21 are coupled to each other. The case of inoperative state is demonstrated.

The driving force of the engine E is transmitted to the front cover 1, and the driving force of the engine transmitted to the front cover 1 is transmitted to the impeller 3 and the turbine 5. The driving force transmitted to the turbine 5 is transmitted to the transmission T via the spline hub 13 through the engine power shutoff clutch 7. At this time, when the operating state of the engine power shut-off clutch 7 is released, the driving force of the engine is blocked from being transmitted to the transmission T.

When the lockup clutch 13 is operated, the driving force of the engine is transmitted to the front cover 1 and is directly transmitted to the turbine 5 through the lockup clutch 13. And the driving force of the engine transmitted to the turbine (5) can be transmitted to the transmission (T) through the engine power shut off clutch (7).

Apart from this engine power transmission path, the driving force of the motor M can be transmitted to the transmission.

That is, by driving the motor in a state in which the driving force of the engine is transmitted to the transmission, the driving force may also be transmitted to the transmission, and the driving force of the motor or the engine may be transmitted to the transmission, respectively.

As described above, the present invention can not only apply the driving force of the engine and the motor to the driving of the vehicle at the same time, but also can select the driving source of the engine or the motor and apply the driving force of the vehicle by the selected driving source. Therefore, it is possible to satisfy various design conditions of the vehicle and can easily cope with various driving conditions, thereby contributing to the improvement of fuel efficiency of the vehicle.

The vehicle employing the torque converter of the present invention maintains the existing driving performance and reduces the driving force of the vehicle and the vibration caused by the engine driving in the uphill driving, thereby realizing low fuel consumption and improving the commercialization of the vehicle and the various design conditions of the vehicle. Can be satisfied.

4 is a diagram for explaining the operating pressures of the engine power shut-off clutch 7 and the lock-up clutch 13. 5 to 8 are diagrams for describing the operation of the embodiment of the present invention in more detail by explaining the control state of the hydraulic pressure.

5 is a view for explaining the operation of the hydraulic pressure when the engine power shut-off clutch is on (operation) state, the lock-up clutch is on (operation) state. That is, an example in which the lockup clutch is operated while the driving force of the engine is transmitted to the transmission through the turbine is described.

The controller (not shown) controls the engine power shut-off clutch and the lock-up clutch control valve (not shown in the drawings) so that the engine power shut-off clutch 7 is in the on state and the lock-up clutch 13 is in the on state. The operating pressure P3 of the engine power shutoff clutch is formed higher than the lockup clutch operating pressure P1. At the same time, the operating pressure P1 for operating the lockup clutch 13 is formed at a higher pressure than the lockup clutch release pressure P2 for releasing the lockup clutch 13. That is, the lockup clutch operating pressure P1 acts in the direction in which the piston of the lockup clutch 13 contacts (operates), and the lockup clutch release pressure P2 can be discharged to the oil tank side. In addition, hydraulic pressure may be supplied from the oil tank so that the engine power cutoff clutch operating pressure P3 is higher than the lockup clutch operating pressure P1. Accordingly, the piston 23 of the engine power transmission shut off clutch 7 moves in the direction in which the engine power transmission shutoff clutch 7 is in contact (operation) so that the friction between the first friction material and the second friction materials 19 and 21 are mutually reduced. Is brought into contact. In the above, the lockup clutch operating pressure P1 is introduced into the front cover through the first port 25 and is formed. In this way, the oil inside the torque converter may be prevented from generating high heat in the engine power shut-off clutch 1, thereby increasing the marketability of the torque converter.

Subsequently, FIG. 6 is a view for explaining the operation of hydraulic pressure when the engine power shutoff clutch 7 is in an on (operation) state and the lockup clutch is in an off (non-operation) state. That is, an example in which the lockup clutch is deactivated while the driving force of the engine is transmitted to the transmission through the turbine is described.

The controller (not shown) controls the valves such that the engine power shutoff clutch 7 is on and the lockup clutch 13 is off. The engine power shutoff clutch operating pressure P3 is formed higher than the lockup clutch operating pressure P1, or the engine power shutoff clutch release pressure. At the same time, the release pressure P2 for releasing the lockup clutch 13 is formed at a higher pressure than the lockup clutch operating pressure P1 for activating the lockup clutch 13. That is, the lockup clutch release pressure P2 acts in the direction in which the piston of the lockup clutch 13 is deactivated (released), and the lockup clutch operating pressure P1 can be discharged to the oil tank side. In addition, the engine power cutoff clutch operating pressure P3 may be supplied with hydraulic pressure from the oil tank so as to be higher than the lockup clutch operating pressure P1. Therefore, the piston 23 of the engine power transmission blocking clutch 7 moves in the direction in which the engine power transmission blocking clutch 7 is in contact (operation), thereby contacting each other between the first friction material and the second friction materials 19 and 21. It becomes a state. In the above, the lockup clutch operating pressure P1 may be discharged to the oil tank side through the first port 25.

Hybrid vehicle torque converter applied to an embodiment of the present invention has the advantage that can be more easily controlled hydraulic pressure.

The present invention can use the driving force of the motor and the engine at the same time as the driving source of the vehicle, and can also satisfy the design conditions of the various vehicles by applying a torque converter that can use the driving force of the motor or engine, respectively, and according to the driving conditions of the vehicle Since a motor or an engine can be used simultaneously or individually as a driving source of the vehicle, the vehicle can easily cope with various driving conditions, thereby contributing to the improvement of fuel efficiency of the vehicle. In addition, the present invention can prevent the occurrence of high heat in the engine power shut off clutch can increase the reliability of the torque converter to improve the marketability.

In addition, the present invention, the driving force of the engine transmitted to the engine power shut-off clutch can secure enough inertia (function of the flywheel) to smooth the rotation through the torque converter, and also the quality of the transmission by damper action through the fluid There is an effect to improve. In addition, the structure of the present invention can be installed by separating the motor from the torque converter has the effect of further improving the merchandise by reducing vibration and the like.

Claims (9)

A front cover rotating by the driving force of the engine; An impeller coupled to the front cover to rotate together; A turbine disposed facing the impeller; A stator positioned between the impeller and the turbine to change oil flow from the turbine to the impeller side; A lockup clutch coupled to the turbine, the lockup clutch capable of transmitting an engine driving force directly to the turbine; And An engine power cutoff clutch coupled to one side of the turbine to cut off power of the engine transmitted from the turbine or to the input shaft of the transmission; Hybrid vehicle torque converter comprising a. The method according to claim 1, The engine power shut-off clutch is a hybrid vehicle torque converter having one side coupled to the spline hub is splined to the input shaft of the transmission. The method according to claim 1, The engine power shut-off clutch is a hybrid vehicle torque converter consisting of a multi-plate clutch. The method according to claim 1, And the engine power shutoff clutch is disposed between the front cover and the turbine. The method according to claim 1, The engine power shut off clutch A first power transmission member coupled to the turbine or turbine shaft; At least one first friction material coupled to the first power transmission member; A second power transmission member coupled to a spline hub splined to the transmission input shaft; At least one second friction material capable of transmitting a driving force of the engine to the spline hub by frictional contact corresponding to the first friction material and coupled to the second power transmission member; A piston disposed on one side of the first friction material or the second friction material such that the first friction material and the second friction material are contacted or released from each other by hydraulic pressure; Hybrid vehicle torque converter comprising a. The method according to claim 2, The spline hub is a torque converter for a hybrid vehicle, each bearing is disposed for smooth rotation in the axial direction between the front cover and the turbine shaft and the corresponding portion. A front cover that rotates by the driving force of the engine, an impeller coupled to the front cover to rotate together, a turbine disposed facing the impeller, positioned between the impeller and the turbine to direct the flow of oil from the turbine to the impeller side. A change-up stator, a lockup clutch coupled to the turbine to directly transfer the driving force of the engine to the turbine, and an engine power cutoff coupled to one side of the turbine to cut off the power of the engine transmitted from the turbine or to the input shaft of the transmission. In the method for hydraulically controlling the lock-up clutch and the engine power shut-off clutch of a hybrid vehicle torque converter comprising a clutch, The operating pressure at which the engine power shut-off clutch is operated and the release pressure at which the engine power cut-off clutch is released are controlled, and the operating pressure at which the lock-up clutch is operated is supplied. The release pressure of the engine power cut-off clutch is controlled. A hydraulic control method of a torque converter for a hybrid vehicle, which is controlled to act as an operating pressure of a clutch. The method according to claim 7, When the engine power shut-off clutch is activated and the lockup clutch is operated, The operating pressure of the engine power shut-off clutch is higher than the operating pressure of the lock-up clutch, and the operating pressure of the lock-up clutch is controlled higher than the release pressure of the lock-up clutch. The method according to claim 7, When the engine power shut-off clutch is activated and the lockup clutch is released, The operating pressure of the engine power shut-off clutch is higher than the operating pressure of the lock-up clutch, and the release pressure of the lock-up clutch is controlled higher than the operating pressure of the lock-up clutch.

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