Abstract:
A key interlock system for use in a vehicle may include a start key having a locking groove and inserted into a start key receiving groove formed in an operating knob which is rotatably received in a switch box, a stopper selectively connecting the switch box with the start key, wherein the stopper includes a body configured to be inserted into the locking groove of the switch key through the switch box and the operating knob, an elastic member resiliently supporting the stopper in a direction against the operating knob, and an actuator generating an operating force to the stopper against an elastic force of the elastic member to selectively insert the stopper into the locking groove of the start key when a shift lever is in any position except for a parking position and the start key is rotated from an ON position to an ACC position.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application claims priority to Korean Patent Application Number 10-2008-119617, filed on Nov. 28, 2008, the entire contents of which are incorporated herein for all purposes by this reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the invention 
         [0003]    The present invention relates to a key interlock for use in vehicles, and more particularly, to a key interlock capable of preventing an ignition key from being released when a shift lever is in any position except that the shift lever is in a parking position. 
         [0004]    2. Description of Related Art 
         [0005]    In general, a transmission for use in vehicles employs a key interlock system which can allow a start key to be released only when a shift lever is in a parking position. 
         [0006]      FIG. 1  is a view illustrating a conventional key interlock, and  FIG. 2  is a view explaining the operation of the key interlock. 
         [0007]    The conventional key interlock includes, as shown in  FIGS. 1 and 2 , a parking position switch for detecting shift of a shift lever which is moved to any position except that a shift lever is moved to a parking position P, and a controller (not shown) receiving a signal to notify the controller of the current position of the shift lever. 
         [0008]    As the controller receives and verifies the signal, the controller supplies a power to a solenoid  11  in order to operate a key interlock device  10 . 
         [0009]    If the power is applied to the solenoid  11 , a push unit  12  connected to the solenoid is pushed down by the solenoid  11 , with the push unit prevailing against the resilient force of a spring  13 . Then, the push unit  12  is locked into a cam shaft  14  not to move the cam shaft  14 , and thus prevents release of a key. 
         [0010]    That is, in the case where the shift lever is in any position except for the parking position P, it prevents the release of the key. 
         [0011]    Meanwhile, if the shift lever is in the parking position P, the controller interrupts the supply of the power to the solenoid  11 , and the push unit  12  is drawn out from the cam shaft  14  to allow the cam shaft  14  to move, thereby releasing the key. 
         [0012]    With the conventional key interlock device  10 , however, if the key is rotated to a lock position in a state that the push unit  12  is in an ACC position to unlock the cam shaft  14 , the key may be released even though the shift lever is in any position except for the parking position. Since a rotation angle of the key is small (e.g. 55 degrees when showing in  FIG. 2 ), the cam shaft  14  is rotated and is in the lock position before the push unit  12  blocks the rotation of the cam shaft  14  by using the solenoid  11 . 
         [0013]    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 OF THE INVENTION 
       [0014]    Various aspects of the present invention are directed to provide key interlock capable of preventing an ignition key from being released when a shift lever is in any position except that the shift lever is in a parking position. 
         [0015]    The key interlock system for use in a vehicle, may include a start key provided with a locking groove on its side portion and configured to be inserted into a start key receiving groove formed in an operating knob which is rotatably received in a switch box; a stopper selectively connecting the switch box with the start key, wherein the stopper includes a body configured to be inserted into the locking groove of the switch key through the switch box and the operating knob; an elastic member resiliently supporting the stopper in a direction against the operating knob; and an actuator generating an operating force to the stopper against an elastic force of the elastic member to selectively insert the stopper into the locking groove of the start key when a shift lever is in any position except for a parking position and the start key is rotated from an ON position to an ACC position. 
         [0016]    The actuator may include a solenoid generating a magnetic force to apply the operating force to the stopper. 
         [0017]    The stopper may have a rear end portion with an inclined surface, and the actuator includes an inclined surface at its front end portion which comes in close contact with the inclined surface of the stopper. 
         [0018]    With the above description, the key interlock system is adapted so that the start key is not released even though the start key is quickly rotated from an ON position to an ACC position when the shift lever is in the parking position. Therefore, the present invention can prevent the accident from occurring and improve safety of passengers. 
         [0019]    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 of the Invention, which together serve to explain certain principles of the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]      FIG. 1  is a view illustrating a conventional key interlock. 
           [0021]      FIG. 2  is a view explaining the operation of the key interlock. 
           [0022]      FIG. 3  is a view illustrating an exemplary key interlock system according to the present invention. 
           [0023]      FIG. 4  is a table of power distribution of an ignition switch for use in an exemplary key interlock system according to the present invention. 
           [0024]      FIG. 5  is a cross-sectional view illustrating an exemplary key interlock according to the present invention. 
           [0025]      FIG. 6  is an enlarged view of portion A in  FIG. 5 . 
           [0026]      FIG. 7  is a view illustrating the operation of an exemplary key interlock according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0027]    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. 
         [0028]    Hereinafter, a key interlock for use in vehicles according to various embodiments of the present invention will now be described with reference to  FIGS. 3 to 7 . 
         [0029]    A key interlock system according to various embodiments of the present invention includes, as shown in  FIG. 3 , a parking position switch  100  for determining whether a shift lever  200  is in a parking position, an ignition switch  300  connected to any one of power terminals to supply a power to various electronic/electric parts from a battery in accordance with manipulation of a start key, and a key interlock controller  400  for determining operation of a key interlock  500  by combining a signal detected by the parking position switch  100  and a signal detected by the ignition switch  300 . 
         [0030]    The parking position switch  100  is installed to the shift lever  200  to determine whether the shift lever  200  is in a parking (P) position or not. 
         [0031]    More specifically, if a driver positions the shift lever  200  at the parking position, the parking position switch  100  generates an ON signal to indicate that the shift lever  200  is in the P position. 
         [0032]    If the driver positions the shift lever  200  at a reverse (R), neutral (N), drive (D), first or second position, except for the P position, the parking position switch  100  generates an OFF signal to indicate that the shift lever  200  is in any position except for the P position. 
         [0033]    The ignition switch  300  is installed to the key interlock  500 , and the key interlock  500  supplies the power to the electronic/electric parts from the battery in accordance with manipulation of the ignition key provided in the ignition switch  300 . 
         [0034]    The key interlock  500  is provided with ROCK, ACC, ON, and START positions, and ignition key may be positioned at the respective terminals. 
         [0035]    The ignition switch  300  is connected to a B 1  terminal and the ACC position if the ignition key is at the ACC position. If the ignition key is at the ON position, the B 1  terminal is connected to the ACC position and an IG 1  terminal, and simultaneously a B 2  terminal is connected to an IG 2  terminal, as shown in  FIG. 4 . If the ignition key is at the start position, the B 1  terminal is connected to the IG 1  terminal, and simultaneously the B 2  terminal is connected to an ST terminal. 
         [0036]    The IG 1  is to supply the power to a fuel circuit, an ignition circuit, an electronic controller, a direction indictor, and a reverse light, and the IG 2  is to supply the power to a light unit, a security unit, an air conditioning unit, and a power window unit. 
         [0037]    The ACC position is to supply the power to a watch and an audio appliance, and the ST terminal is to supply the power to a start circuit. The B 1  is a battery power for electronic/electric parts related to the ACC position and the IG 1 , and the B 2  terminal is a battery power for electronic/electric parts related to the ST terminal and the IG 2  terminal. 
         [0038]    The key interlock controller  400  is to determine the operation of the key interlock  500  which will be described hereinafter. The determination in the operation of the key interlock  500  is implemented by the signals generated from the parking position switch  100  and the ignition switch  300 . 
         [0039]    More specifically, if the shift lever  200  is in a parking position, receives an ON signal from the switch  100 , and the controller  400  receives an IG 1  from the ignition switch  300 , the controller  400  does not operate the key interlock  500  so that the start key can be released from the key interlock  500 . However, the controller  400  operates the key interlock  500  in response to other signals to prevent the start key from being released from the key interlock  500 . 
         [0040]    The key interlock  500  is to allow the start key to release from the ignition switch only when the shift lever  200  is in the parking position. The key interlock  500  includes, as shown in  FIG. 5 , a switch box  510  built in a dash board adjacent to a steering wheel, an operation knob  520  rotatably connected to the switch box  510  and provided with a start key receiving groove on its inner surface, a start key  530  inserted into the groove of the operation knob  520  and rotating the operation knob  520 , the start key  530  being provided with a locking groove  531  on its side portion, a stopper  540  inserted into the groove  511  formed on the side of the switch box  510  and having a front end portion penetrating through the hole  521  formed on the side of the operation knob  520  and inserted into the locking hole  531 , a spring  550  provided in the groove  511  and resiliently supporting the stopper  540  in a direction opposite to the locking groove  531 , and a solenoid  560  generating a magnetic force to insert the stopper  540  into the locking groove  531  when the shift lever  200  is in any position except for the parking position and the start key  530  is rotated from the ON position to the ACC position. 
         [0041]    The stopper  540  includes a support portion  541  movably inserted into the groove  511 , a locking portion  542  formed on one side of the support portion  541  and having a front end portion selectively inserted into the groove  531 , and a movable portion  543  extending from the other side of the support portion beyond the switch box  510  and having a rear end portion with an inclined surface  543   a.    
         [0042]    More specifically, if the rod  561  of the solenoid  560  is pulled out, the inclined surface  543   a  of the movable portion  543  is pressurized along the inclined surface  561   a  of the rod  561 , and the stopper  540  is moved and inserted into the locking groove  531  of the start key  530 , thereby locking the start key  530  and preventing release of the start key. 
         [0043]    In this instance, the spring  550  is compressed by the support portion  541 . 
         [0044]    And then, if the power of the solenoid  560  is intercepted, the rod  561  is returned to its original position, and the support portion  541  is returned to its original position by the resilient restoring force of the spring  550 . The locking portion  542  is released from the locking groove  531 , and the locking state of the start key  530  is released. 
         [0045]    The operation of the key interlock for use in vehicles according to various embodiments of the present invention will now be described. 
         [0046]    Explaining the key interlock system in brief, first of all, it is determined whether the IG 1  is in ON state on the basis of the ignition switch  300 . Wherein, the state where the IG 1  is in ON state means that the ignition key is in an ON or START position. 
         [0047]    The controller  400  determines whether the ON signal is generated from the parking position switch  100 . 
         [0048]    The ON signal means that the shift lever  200  is in the parking position. The controller  400  does not operate the key interlock  500  by turning off the solenoid  560 . 
         [0049]    More specifically, if the shift lever  200  is in the parking position, the key interlock  500  is not operated, and thus the start key  530  may be released from the operation knob  530 . 
         [0050]    If the ON signal is not generated from the parking position switch  100 , it is determined that the shift lever  200  is in any positions. 
         [0051]    In this instance, if the IG 1  is not ON, it is determined that the start key  530  is in the LOCK or ACC position, and the key interlock  500  is operated by turning off the solenoid  560 , thereby preventing the release of the start key  530 . 
         [0052]    Meanwhile, in the case where the shift lever  200  is in any position except for the parking position, that is, the start key  530  is in the ON position while driving, the key interlock  500  does not operated. 
         [0053]    When the start key  530  is quickly rotated from the ON position to the ACC position, the IG 1  detects the OFF. Thus, the solenoid  560  is turned off to operate the key interlock  500  and prevent the release of the start key  530 . 
         [0054]    More specifically, if the solenoid  560  is turned on, the rod  561  of the solenoid  560  is drown out, and the inclined surface  541   a  of the stopper  540  is pressurized and moved. And thus, the locking portion  542  is inserted into the locking groove  531  of the start key  530  to prevent the release of the start key  530 . 
         [0055]    As shown in  FIG. 7 , even though the start key  530  is quickly rotated from the ON position to the ACC position at small rotation angle (e.g. 55 degrees when viewing from  FIG. 5 ), it can prevent the release of the start key  530  through the key interlock  500  and thus improve the safety of the vehicle. 
         [0056]    If the start key  530  is not rotated from the ON position to the ACC position in a state that the shift lever  200  is in the parking position, the power is not applied to the solenoid  560 . And then, if the shift lever  200  is moved to the parking position, the start key  530  can be normally released. 
         [0057]    The key interlock  500  is operated while the shift lever  200  is in any positions except for the parking position. In order to move the shift lever  200  to the parking position, the start key  530  is moved to the ON position, and then the shift lever is moved. 
         [0058]    In this instance, when the start key  530  is in at the ON position, the IG 1  becomes ON to intercept the power of the solenoid  560 . And thus, the stopper  540  is returned to its original position by the restoring force of the spring  550  to release the start key  530 . 
         [0059]    For convenience in explanation and accurate definition in the appended claims, the terms “front”, “rear”, and “inner” are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures. 
         [0060]    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.