Abstract:
An active air flap apparatus for a vehicle in which upon the generation of a failure whereby an air flap is not able to be activated with power from an actuator, the connection between a guide frame and a flap loader is manually released, enabling the air flap to automatically be opened by wind produced by the vehicle.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority of Korean Patent Application Number 10-2011-0130987 filed Dec. 8, 2011, 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, in general, to an active air flap apparatus for a vehicle and, more particularly, to an active air flap apparatus for a vehicle in which upon the generation of a failure, a connection structure between an actuator and an air flap is manually released, enabling the air flap to be automatically opened by wind supplied by the vehicle. 
     2. Description of Related Art 
     A variety of heat exchangers, such as a radiator, an intercooler, a vaporizer, a compressor, etc., as well as driving parts such as engine and the like, are generally present in an engine compartment. 
     Such heat exchangers contain an intermediate heat-exchange medium that moves therethrough to exchange heat with the external air so that the external air is cooled or heated. In order for activation of the heat exchanger installed in the engine compartment to be dependable, external air has to be smoothly supplied into the engine compartment. 
     However, upon high speed traveling of a vehicle or the like, a great amount of external air is quickly introduced, air resistance increases and thus the fuel efficiency drops. 
     To solve this problem, an active air flap apparatus has been developed in which upon traveling at low speeds, an angle of opening is made larger so as to increase the inflow of air into the engine compartment, and upon traveling at high speeds, the angle of opening is reduced so as to cut back on the inflow of air, thereby contributing to fuel efficiency improvements. 
     As shown in  FIGS. 1 to 4 , the conventional active air flap apparatus includes a duct  1  fixedly built to a front end module of a vehicle, an actuator  2  fixedly installed at the central portion of the duct  1 , an H-type guide frame  4  connected with the actuator  2  via an actuator loader  3  so that it can vertically move with the power from the actuator  2 , and an air flap  6  connected with the guide frame  4  via a flap loader  5  and also rotatably installed to the duct  1 . Here, the actuator  2  includes a PCB  2   a , a motor  2   b , and a plurality of gear members  2   c.    
     Thus, when the actuator  2  is activated under an external condition (engine temperature, cooling-water temperature, etc.), the power from the actuator  2  is transmitted to the guide frame  4  via the actuator loader  3 , the guide frame  4  vertically moves as shown in the figures so that the flap loader  5  rotates, and finally the rotating force of the flap loader  5  is transmitted to the air flap  6  and thus rotates the air flap  6  so that the duct  1  is opened or closed. 
     In the active air flap apparatus, if the actuator  2  fails to operate owing to an electrical short-circuit or failure of the motor  2   a  or the like, it is impossible to operate the air flap  6  while a vehicle is in motion. In particular, if the operation of the air flap  6  is impossible under the situation where the air flap  6  blocks the duct  1 , temperature of the engine and other heat exchangers increases, causing the vehicle to have serious problems. 
     The information disclosed in this Background 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. 
     SUMMARY OF INVENTION 
     Accordingly, the present invention has been made keeping in mind the above problems occurring in the related art to provide an active air flap apparatus for a vehicle in which upon the generation of a failure, a connection structure between an actuator and an air flap is manually released, enabling the air flap to be automatically opened by wind produced by the vehicle, thereby preventing vehicle parts from being damaged. 
     Various aspects of the present invention provide for an active air flap apparatus for a vehicle, including a guide frame having a vertical column having a coupling hole, into which a flap loader is fitted, and a rod hole extending throughout the vertical column in such a manner as to be connected with the coupling hole, and an operating rod fitted into the rod hole in such a manner as to be moved along the rod hole, the operating rod having a coupling groove into which the flap loader is fitted. 
     The maximum depth of the coupling groove may be greater than the depth of the coupling hole. 
     The shape of the portion of the vertical column where the coupling hole is formed may be a linear shape of constant thickness. 
     The flap loader may be configured such that when the flap loader is fitted into the coupling groove, the flap loader is vertically moved together with the guide frame, and when the flap loader disengages from the coupling groove as the operating rod moves, the flap loader disengages from the coupling hole. 
     As previously set forth, according to the present invention, upon the generation of a failure whereby the air flap cannot be activated with power from the actuator, the connection between the guide frame and the flap loader is manually released, enabling the air flap to be automatically opened by wind produced by the vehicle, thereby preventing vehicle parts from being damaged due to the failure of the air flap. 
     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 view explaining a conventional active air flap apparatus. 
         FIG. 2  is a view explaining an actuator of the active air flap apparatus of  FIG. 1 . 
         FIG. 3  is an enlarged view showing a coupled portion of the actuator of the active air flap apparatus of  FIG. 1 . 
         FIG. 4  is a cross-sectional view taken along line I-I of  FIG. 3 . 
         FIG. 5  is a view showing an exemplary active air flap apparatus according to the present invention in which an operating rod is coupled to a guide frame. 
         FIG. 6  is a cross-sectional view taken along line of  FIG. 5 . 
         FIGS. 7 and 8  are views showing the state in which upon generation of a failure, an exemplary flap loader is disconnected from the guide frame by the operating rod. 
     
    
    
     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 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. 
     As shown in  FIGS. 5 and 6 , an active air flap apparatus according to various embodiments includes a duct  10  fixedly built in a front end module of a vehicle, an actuator  20  fixedly installed at the central portion of the duct  10 , an H-type guide frame  40  connected with the actuator  20  via an actuator loader  30  so that it can be vertically moved by the power from the actuator  20 , and an air flap  60  connected with the guide frame  40  via a flap loader  50  and also rotatably installed to the duct  10 . 
     Here, the guide frame  40  has an H-type structure which includes two parallel vertical columns  41  and a horizontal column  42  connecting the vertical columns  41 . The vertical column  41  is provided in both upper and lower sides with a coupling hole  43  into which one end of the flap loader  50  is fitted. The vertical column  41  also has, on the intermediate portion, a protrusion  44  having a fitting groove  45  into which an end of the actuator loader  30  is fitted. 
     In addition, the vertical column  41  of the guide frame  40  is provided with a rod hole  46  that vertically transects the vertical column such that it is connected with the coupling hole  43 . 
     The active air flap apparatus includes an operating rod  70  which is fitted into the rod hole  46  in such a manner as to move inside the rod hole  46 . The operation rod  70  has a coupling groove  71  to which the flap loader  50  is fitted. 
     Here, when the flap loader  50  is in the state of being fitted into the coupling groove  71  of the operating rod  70 , the flap loader  50  can vertically move with movement of the guide frame  40 . 
     When the flap loader  50  disengages from the coupling groove  71  as the operating rod  70  moves inside the rod hole  46 , the flap loader  50  becomes disengaged from the coupling hole  43  and thus disconnected from the guide frame  40  as shown in  FIGS. 7 and 8 . 
     In order to allow the flap loader  50  to disengage from the coupling hole  43  when it  50  disengages from the coupling groove  71 , the maximum depth D 1  of the coupling groove  71  is preferably greater than the depth D 2  of the coupling hole  43 , and the shape of the portion of the vertical column  41  of the guide frame  40  where the coupling hole  43  is formed is preferably be linear and of a constant thickness. 
     Now the operation of the active air flap will be described. 
     When the actuator  20  is activated under the normal condition of there being no electrical short-circuit or failure, the power from the actuator  20  is transmitted to the guide frame  40  via the actuator loader  30  so that the guide frame  30  can vertically move from the state shown in  FIG. 5 . 
     When the guide frame  40  vertically moves, one end of the flap loader  50 , fitted into the coupling hole  43 , also vertically moves together with the guide frame  40  so that the rotating force of the flap loader  50  is transmitted to and rotates the air flap  60 , thereby opening or closing the duct  10 . 
     In the case of a failure being generated due to an electrical short-circuit or the like, although the actuator  20  is activated, the power from the actuator  20  cannot be transmitted to the air flap  60 , so that the air flap  60  cannot be opened or closed. 
     In particular, if while a vehicle travels, the operation of the air flap  60  is impossible under the situation where the air flap  60  blocks the duet  10 , the temperature of the engine and other heat exchangers increases, possibly causing the vehicle to have serious problems. 
     Thus, to solve this problem, an operator should push down the operating rod  70  from the state shown in  FIG. 6 . 
     As the operating rod  70  moves down inside the rod hole  46  as shown in  FIGS. 7 and 8 , the flap loader  50  disengages from the coupling groove  71  of the operating rod  70  and thus finally from the coupling hole  43 , resulting in the guide frame  40  and the flap loader  50  being disconnected. 
     When the guide frame  40  and the flap loader  50  are disconnected, the air flap  60  is ready to freely rotate under even a slight external force irrespective of the operation of the actuator  20 . Thus, the air flap is freely rotated by wind caused by the vehicle so as to open the duct  10 , so that external air is introduced therethrough, thereby preventing damage to the vehicle parts due to failure of the air flap  60 . 
     For convenience in explanation and accurate definition in the appended claims, the terms upper or lower, front or rear, inside or outside, and etc. 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.