HYBRID POWERTRAIN PROVIDED WITH DOUBLE CLUTCH TRANSMISSION

A hybrid power train provided with a double clutch transmission includes: a first clutch and a second clutch configured to connect or cut off selectively rotational power transmitted from an engine; a first input shaft and a second input shaft that are connected to the first clutch and the second clutch to be rotated; a first motor generator that is connected to the first input shaft and provides the rotational power to the first input shaft; and a second motor generator that is connected to the second input shaft and provides the rotational power to the second input shaft.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority of Korean Patent Application Number 10-2013-0094810 filed Aug. 9, 2013, the entire contents of which application is incorporated herein for all purposes by this reference.

BACKGROUND OF INVENTION

1. Field of Invention

The present invention relates to a hybrid power train, and more particularly, to a hybrid power train provided with a double clutch transmission, capable of improving fuel ratio by combining a hybrid structure to manual shifting mechanism of a double clutch transmission.

2. Description of Related Art

Recently, a fuel ratio improvement has been further required for replying to a high fuel cost and CO2environmental regulations and thus continuous researches and developments of environment vehicles such as electrical vehicles and hybrid vehicles the fuel ratio of which are improved while reducing exhaust amount of hazardous gas, have been made.

However, in case of an electrical vehicle, since the prices of a battery and a motor that are essential for driving the electrical vehicle are very high, the price of the electrical vehicle becomes high, comparing to a general vehicle that uses fossil fuel, and thus the environment vehicles have not been generally used.

Under the current situation as described above, one of the most practical way for improving the fuel ratio of the vehicles is to improve efficiency of an internal combustion engine or increase a power transmission efficiency of a power train system.

Meanwhile, a transmission having the best efficiency of a driving system is a manual transmission, and further a power transmission efficiency of a double clutch transmission (DCT) based on the manual transmission is better than those of an automatic transmission or continuously variable transmission (CVT).

Accordingly, the fuel ratio of a general internal combustion engine may be improved by configuring a transmission in a hybrid type through combining a motor to DCT with excellent efficiency.

Meanwhile,FIG. 1is a perspective view showing “double clutch transmission for a hybrid vehicle”, disclosed in Korean Laid-Open No. 10-2007-0021558, according to a related art.

According to the related art, a motor3is connected to only one of two input shafts1,2wherein the rotation number of the motor is determined as one with respect to a specific speed of a vehicle under the transmission as configured as above, and thus the transmission cannot be avoided to operate at an inefficient section.

BRIEF SUMMARY

Various aspects of the present invention has been made in an effort to solve the problems of the related art.

Various aspects of the present invention provide for a hybrid power train provided with a double clutch transmission, capable of improving fuel ratio by combining a hybrid structure that can use multiply rotational power of an engine and a motor to manual shifting mechanism of a double clutch transmission.

Various aspects of the present invention provide for a hybrid power train that may include: a first clutch and a second clutch configured to connect or cut off selectively rotational power transmitted from an engine; a first input shaft and a second input shaft that are connected to the first clutch and the second clutch to be rotated; a first motor generator that is connected to the first input shaft and provides the rotational power to the first input shaft; and a second motor generator that is connected to the second input shaft and provides the rotational power to the second input shaft.

The first input shaft and the second input shaft may be provided concentrically.

The hybrid power train provided with a double clutch transmission may further include an output shaft provided in parallel to the first input shaft and the second input shaft, and a shifting gear device in which a plurality of gear pairs having different shifting ratios are provided to be meshed on the first input shaft, the second input shaft and the output shaft and which selects the pair of gears corresponding to a driving speed by a shifting mechanism when a vehicle drives and transfers the rotational power transmitted from the first input shaft or the second input shaft to the output shaft with shifting the rotational power.

The shifting gear device may include: a first shifting gear set where a pair of gears are provided to be meshed constantly therewith on the first input shaft and the output shaft; a second shifting gear set where a pair of gears are provided to be meshed constantly therewith on the second input shaft and the output shaft; and a shifting mechanism for selecting the pair of gears of the first shifting gear set or the pair of the second shifting gear set and transferring the rotational power transmitted from the first input shaft or the second input shaft to the output shaft.

A final reduction gear may be provided concentrically on the output shaft and a differential device is provided to be meshed constantly therewith on the final reduction gear.

The first motor generator and the second motor generator may be connected to a battery for receiving the electric power, or configured to generate electricity.

DETAILED DESCRIPTION

FIG. 2is a perspective view showing a hybrid power train according to various embodiments of the present invention,FIG. 3is a perspective view showing a power transferring path on an EV driving mode according to various embodiments of the present invention,FIG. 4is a perspective view showing a power transferring path on a HEV mode according to various embodiments of the present invention,FIG. 5is a perspective view showing a power transferring path on an engine driving mode according to various embodiments of the present invention, andFIG. 6is a perspective view showing a power transferring path on a series driving mode according to various embodiments of the present invention.

A power train provided with a double clutch transmission according to the present invention includes mainly a first clutch C1and a second clutch C2, a first input shaft11and a second input shaft21, and a first motor generator13and a second motor generator23.

Referring toFIG. 2, the power train provided with a double clutch transmission includes: the first clutch C1and the second clutch C2for connecting or cutting off selectively a rotational power transmitted from an engine1; the first input shaft11and the second input shaft21that are connected to the first clutch C1and the second clutch C2to be rotated; and the first motor generator13that is connected to the first input shaft11and provides the rotational power thereto and the second motor generator23that is connected to the second input shaft21and provides the rotational power thereto.

That is, the first motor generator13is connected to the first input shaft11and the second motor generator23is connected to the second input shaft21, respectively, and the first input shaft11and the second input shaft21are connected or cut off selectively through the first clutch C1and the second clutch C2to transfer the rotation power from an engine1wherein a vehicle can drive on various modes through the driving control of the double clutches, the engine1, and the motor.

Here, the first input shaft11and the second input shaft21may be provided concentrically in the present invention.

Further, an output shaft31may be provided in parallel to the first input shaft11and the second input shaft21. Additionally, a shifting gear device is provided such that a plurality of gear pairs having different shifting ratios are meshed with the first input shaft11, the second input shaft21and the output shaft31. The shifting gear device transfers the rotation power transmitted from the first input shaft11or the second input shaft21to the output shaft31with shifting the rotation power by selecting the gear pair corresponding to a driving speed through a shifting mechanism33when a vehicle drives.

Here, the shifting mechanism33may be a synchronizing device in a synchro-mesh type and a configuration of the synchronizing device is well known and thus detailed description thereof is omitted.

Meanwhile, the shifting gear device may include a first shifting gear set15where gear pairs that are meshed constantly are arranged on the first input shaft11and the output shaft31; a second shifting gear set25where gear pairs that are meshed constantly are arranged on the second input shaft21and the output shaft31; and a shifting mechanism33that transfers the rotation power transmitted from the first input shaft11or the second input shaft21to the output shaft31with selecting the gear pair of the first shifting gear set15or the gear pair of the second shifting gear set25.

That is, in the shifting gear device of the present invention, one shifting gear set is arranged on the first input shaft11and the output shaft31, and another shifting gear set is arranged on the second input shaft21and the output shaft31thereby to simplify at a maximum level a gear configuration of the shifting gear device for implementing manual shifting mechanism and further to improve shifting transferring efficiency and fuel ratio with applying a transmission with a double clutch structure.

Here, the gear arranged to the output shaft31among the gear pairs that constitute the first shifting gear set15and the second shifting gear set25is rotatable relatively with respect to the output shaft31wherein the shifting mechanism33is arranged on the output shaft31between the first shifting gear set15and the second shifting gear set25, and thus the shifting mechanism33is moved to the first shifting gear set15or the second shifting gear set25to be synchronized with the gear arranged on the output shaft31.

Furthermore, a final reduction gear35is arranged concentrically on the output shaft31and a differential device40may be provided on the final reduction gear35to be meshed constantly therewith.

That is, the rotation power transmitted to the output shaft31is transferred to the differential device40through the final reduction gear35thereby to drive a vehicle.

Meanwhile, the first motor generator13and the second motor generator23are connected to a battery50to receive electric power necessary for rotation, or configured to generate electricity.

That is, the engine1and the motor as well as the double clutch are driving-controlled by an electronic control unit (ECU) and a telecommunication control unit (TCU) and thus other motor generators can generate electricity using the power from the engine1while driving on an EV mode with the motor generators.

A control and power transferring path for transferring power on various driving modes according to the hybrid power train of the present invention will be described.

FIG. 3is a perspective view showing a power transferring path according to various embodiments of the present invention.

Referring toFIG. 3, the first motor generator13is rotated through the battery50while releasing all of the first clutch C1and the second clutch C2. At this time, the shifting mechanism33selects the first shifting gear set5and is fastened thereto and thus the rotation power of the first motor generator13is transferred to the output shaft31through the first input shaft11and the first shifting gear set15thereby to drive a vehicle on an EV mode in which a vehicle drives using only electric power.

Furthermore, the battery50can be charged through the second motor generator23by connecting the second clutch C2while driving on EV mode, and further the engine1can be started-on using the rotation power of the second motor generator23with driving the second motor generator23by connecting the second clutch C2when it intends to change to HEV mode from EV mode.

FIG. 4is a perspective view showing a power transferring path on a HEV mode according to various embodiments of the present invention.

Referring toFIG. 4, the power from the engine1is transferred to the first input shaft11by connecting the first clutch C1and the first motor generator13is driven to rotate to transfer the rotation power of the motor generator13to the first input shaft11together. At this time, the shifting mechanism33selects the first shifting gear set15and fastened thereto and thus the rotation powers of the engine1and the first motor generator13are transferred to the output shaft31through the first input shaft11and the first shifting gear set15thereby to drive a vehicle on an HEV mode in which a vehicle drives using combination of engine power and electric power.

FIG. 5is a perspective view showing a power transferring path on an engine1driving mode according to various embodiments of the present invention.

Referring toFIG. 5, the power from the engine1is transferred to the second input shaft21by connecting the second clutch C2. At this time, the shifting mechanism33selects the second shifting gear set25and fastened thereto and thus the rotation power of the engine1is transferred to the output shaft31through the second input shaft21and the second shifting gear set25thereby to drive a vehicle on an engine1driving mode in which a vehicle drives using engine power.

FIG. 6is a perspective view showing a power transferring path on a series driving mode according to various embodiments of the present invention.

Referring toFIG. 6, the power from the engine1is transferred to the second input shaft21by connecting the second clutch C2and the first motor generator13is driven through the battery50to transfer the rotation power to the first input shaft11. At this time, the shifting mechanism33selects the first shifting gear set15and fastened thereto wherein the rotation power of the engine1is transferred to the second motor generator23to charge the battery50. Accordingly, a vehicle can drive on a series driving mode in which a vehicle drives using electric power while charging the battery50using the power from the engine1.

Here, the power transferring paths shown inFIGS. 3 to 6are provided only for helping to understand the present invention and thus the power transferring path can be varied through the driving control of the double clutch, the engine1and the motor generator.

According to the present invention, a vehicle can drive on various driving modes through configuring a hybrid structure in which motor generators are mounted to the respective input shafts of a manual shifting mechanism of a double clutch, and controlling to drive the double clutch, the engine and the motor generator. Further, the gear configuration of the shifting gear device is simplified to improve a shifting efficiency and fuel ratio.