Abstract:
A dual clutch device for a vehicle may include a drive motor provided in a motor housing, a clutch housing connected to the motor housing wherein a clutch may be provided in the clutch housing, and a cooling oil flowing unit forming a hydraulic line fluid-connecting the motor housing and the clutch housing and supplying a cooling oil to the drive motor and the clutch through the hydraulic line.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority to Korean Patent Application No. 10-2012-0066915 filed on Jun. 21, 2012, the entire contents of which is incorporated herein for all purposes by this reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a dual clutch device for a vehicle. More particularly, the present invention relates to a dual clutch device for a vehicle which cools a clutch of the vehicle using a cooling mechanism of a drive motor. 
     2. Description of Related Art 
     Generally, a continuously variable transmission (CVT) is used as a transmission of a hybrid electric vehicle. A metal belt that can change an engine speed within a gear range irrespective of a vehicle speed is applied to the continuously variable transmission. 
     The continuously variable transmission (CVT) using the metal belt, however, uses relatively high hydraulic pressure compared with other automatic transmission. Therefore, the continuously variable transmission (CVT) has many drawbacks in efficiency regardless of excellent functionality. 
     Recently, use of a dual clutch transmission (DCT) is increasing. The dual clutch transmission has merits of excellent efficiency of a manual transmission and convenience of an automatic transmission. According to the dual clutch transmission, a plurality of input gears is disposed on two input shafts and any one of a plurality of output gears engaged with the plurality of input gears is selectively connected to any one of two output shafts by means of a synchronizer device. Thereby, a shift is performed. 
     According to a conventional dual clutch transmission, however, a cooling circuit may be very complicated and lubrication performance may be insufficient. Therefore, shift feel may be deteriorated. 
     The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art. 
     BRIEF SUMMARY 
     Various aspects of the present invention are directed to providing a dual clutch device for a vehicle having advantages of improving shift feel due to improvement of lubrication performance by cooling the dual clutch device using a cooling mechanism of a drive motor without using additional components. 
     In an aspect of the present invention, a dual clutch device for a vehicle may include a drive motor provided in a motor housing, a clutch housing connected to the motor housing wherein a clutch is provided in the clutch housing, and a cooling oil flowing unit forming a hydraulic line fluid-connecting the motor housing and the clutch housing and supplying a cooling oil to the drive motor and the clutch through the hydraulic line. 
     The cooling oil flowing unit may include an inlet formed at an upper portion of the motor housing, an outlet formed at a lower portion of the motor housing, a cooling channel formed between the motor housing and the drive motor and fluid-connected to the inlet and the outlet, and a connecting line fluid-connecting the cooling channel with an inside of the clutch housing, wherein the cooling oil is supplied in the cooling channel through the inlet, and wherein the cooling oil is discharged from the cooling channel and the clutch housing through the outlet. 
     The connecting line is formed slanted inwardly from the motor housing toward the clutch. 
     The dual clutch device may include a cap member mounted at the inlet or the outlet. 
     The cap member is threaded to a screw thread formed at an interior circumference of the inlet or the outlet. 
     The connecting line may include an upper connecting line fluid-connected to the inlet, the cooling channel and the inside of the clutch housing. 
     The connecting line may include a lower connecting line fluid-connected to the outlet, the cooling channel and the inside of the clutch housing. 
     In another aspect of the present invention, a dual clutch device for a vehicle may include a motor housing provided with an inlet receiving a cooling oil therethrough and an outlet discharging the cooling oil therefrom, a drive motor mounted in the motor housing, wherein the motor housing is provided with a cooling channel fluid-connected to the inlet and the outlet, a clutch housing connected to the motor housing, a clutch mounted in the clutch housing, and a connecting line formed at a wall formed between the motor housing and the clutch housing and dividing the drive motor from the clutch, and fluid-connecting the cooling channel to an inside of the clutch housing. 
     The dual clutch device may include a cap member threaded to the inlet or the outlet of the motor housing. 
     The connecting line is formed slanted inwardly from the drive motor to the clutch. 
     The inlet is formed at an upper portion of the motor housing and the outlet is formed at a lower portion of the motor housing. 
     The connecting line may include an upper connecting line fluid-connected to the inlet, the cooling channel and the inside of the clutch housing. 
     The connecting line may include a lower connecting line fluid-connected to the outlet, the cooling channel and the inside of the clutch housing. 
     The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description, which together serve to explain certain principles of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional view of a dual clutch device for a vehicle according to an exemplary embodiment of the present invention. 
         FIG. 2  is an enlarged view of “A” region in  FIG. 1 . 
         FIG. 3  is a cross-sectional view illustrating thread-coupling of a cap member shown in  FIG. 2 . 
     
    
    
     It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment. 
     In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing. 
     DETAILED DESCRIPTION 
     Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that the present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims. 
     Description of components that are not necessary for explaining the present exemplary embodiment will be omitted, and the same constituent elements are denoted by the same reference numerals in this specification. 
     Since size and thickness of each component illustrated in the drawings are arbitrarily represented for ease of explanation, the present invention is not limited to the drawings. Thicknesses of many parts and regions are enlarged. 
       FIG. 1  is a cross-sectional view of a dual clutch device for a vehicle according to an exemplary embodiment of the present invention,  FIG. 2  is an enlarged view of “A” region in  FIG. 1 , and  FIG. 3  is a cross-sectional view illustrating thread-coupling of a cap member shown in  FIG. 2 . 
     Referring to  FIG. 1  and  FIG. 2 , a dual clutch device  100  for a vehicle according to an exemplary embodiment of the present invention is adapted to cool a clutch  120  of a vehicle using cooling mechanism of a drive motor  110  without using additional components. Therefore, a length and a size of the clutch  120  may be reduced without changing a layout of a conventional transmission, and shift feel may be improved by improving lubrication performance of the clutch  120 . 
     For these purposes, the dual clutch device  100  for a vehicle according to an exemplary embodiment of the present invention includes the drive motor  110 , the clutch  120 , and a cooling oil flowing unit  130 , and each component will be described in detail. 
     The drive motor  110  is mounted in a motor housing  111 . 
     The clutch  120  includes a clutch housing  121  connected to the motor housing  111  and is mounted in the clutch housing  121 . 
     In an exemplary embodiment of the present invention, the cooling oil flowing unit  130  forms a hydraulic line connecting the drive motor  110  with the clutch  120  through the motor housing  111 , and supplies a cooling oil to the drive motor  110  and the clutch  120  through the hydraulic line. 
     The cooling oil flowing unit  130  includes an inlet  131 , an outlet  132 , a cooling channel  133 , and connecting lines  135  and  136 . 
     The inlet  131  is formed at an upper portion of the motor housing  111  so as to flow the cooling oil in the motor housing  111 , and the outlet  132  is formed at a lower portion of the motor housing  111  so as to discharge the cooling oil from the motor housing  111 . 
     Cap members  150  are mounted respectively at the inlet  131  and the outlet  132  formed at the motor housing  111 . 
     The cap members  150 , as shown in  FIG. 3 , may be threaded to screw threads  151  formed at interior circumferences of the inlet  131  and the outlet  132  of the motor housing  111 . 
     In addition, the cooling channel  133  is connected to the inlet  131  and the outlet  132  and is formed between the motor housing  111  and the drive motor  110 . 
     The cooling channel  133  is a space in which the cooling oil flows and which is adapted to cool the drive motor  110 . 
     The connecting lines  135  and  136  are formed at a wall  140  formed between the motor housing  111  and the clutch housing  121  and dividing the drive motor  110  from the clutch  120 . The connecting lines  135  and  136  connect the cooling channel  133  with an inside of the clutch housing  121 . 
     In addition, the connecting lines  135  and  136  are formed slanted inwardly toward the clutch  120  with respect to the drive motor  110  in a radial direction. Therefore, the cooling oil flowing into the cooling channel  133  through the inlet  131  is flowed into the clutch  120  easily and the cooling oil cooling the clutch  120  is exhausted from the clutch  120  through the outlet  132 . 
     That is, if the cooling oil flows into the cooling channel  133  through the inlet  131  formed at the upper portion of motor housing  111 , the cooling oil flows into the clutch housing  121  through the upper connecting line  135  and cools the clutch  120 . After that, the cooling oil flows out to cooling channel  133  through the lower connecting line  136 , and then is exhausted to the exterior of the motor housing  111  through the outlet  132  formed at the lower portion of the motor housing  111 . 
     Therefore, the dual clutch device  100  for a vehicle according to an exemplary embodiment of the present invention can cool the clutch  120  of the vehicle simultaneously with the drive motor  110  using the cooling mechanism of the drive motor  110  without using additional components. Therefore, a length and a size of the clutch  120  may be reduced without changing a layout of a conventional transmission, and shift feel may be improved by improving lubrication performance of the clutch  120 . 
     For convenience in explanation and accurate definition in the appended claims, the terms “upper”, “lower”, “inner” and “outer” are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures. 
     The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.