Patent Publication Number: US-2009224559-A1

Title: Door latch assembly with damping member of automobile

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to and the benefit of Korean Patent Application No. 10-2008-0027261 filed in the Korean Intellectual Property Office on Mar. 25, 2008, the entire contents of which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     (a) Field of the Invention 
     The present invention relates to a door latch assembly with single complex type damper of an automobile, and more particularly, to a door latch assembly with single complex type damper of an automobile in which a single damping member can perform damping functions for dampening shocks of a pawl and a striker which are provided inside a door latch assembly. 
     (b) Description of the Related Art 
     Generally, a door which is able to be opened and closed and divides the inside and the outside of an automobile to protect passengers and to prevent theft is provided in an automobile, and the door is opened and closed by force applied to a door checker at a pillar which forms a side of a vehicle body. 
     In addition, the door is provided with a door latch which is configured to be coupled to or released from a door striker which is formed to a vehicle body at an opposite side of a portion at which is coupled to a vehicle body by a door checker thereby being opened and closed and at the same time completely closing the door. 
     In the conventional door latch, a claw is coupled to a front surface of a base plate to be selectively rotatable in an open direction or a close direction around a first hinge, and a pawl which rotates around a second hinge so as to maintain the full latch state of the claw by a return spring is provided below the claw. 
     In the conventional door latch which is used as described above, a pawl damper for preventing contact noise of the pawl which operates together with opening and closing operations of the door and stops the pawl is provided thereby reducing contact noise (door-closing sound) of the pawl. 
     Further, in addition to the pawl damper, a striker damper which prevents contact noise between the striker and the claw and has functions for engaging the striker as well as for stopping the striker, i.e, stopping the door is also provided. 
     However, since the conventional door latch for an automobile includes several damping members such as the pawl damper and the striker damper, manufacturing cost is increased due to the number of the damping member and the manufacturing process, and in particular, since the pawl damper surface-contacts the pawl so that contact noise generates when the pawl returns. 
     The information disclosed in this Background of the Invention section is only for enhancement of understanding of the background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art that is already known to a person skilled in the art. 
     SUMMARY OF THE INVENTION 
     The present invention has been made in an effort to provide a door latch assembly with single complex type damper of an automobile in which a single damping member can perform damping functions for dampening shocks of both a pawl and a striker which are provided inside a door latch assembly thereby reducing manufacturing cost by decrease of the number of the damping member and manufacturing processes and closing sound of the door can be improved. 
     An exemplary embodiment of the present invention provides a single complex type damper which is provided to a base plate of a door latch of an automobile door to perform damping function to dampen shocks of both a striker and a pawl lever. 
     The single complex type damper may be formed to have a shape of “ ” having a first damping part and a second damping part which respectively protrude toward directions corresponding to the striker and the pawl lever at an inner surface of the side part and a lower surface of the lower part so as to respectively give damping force to the striker and the pawl lever. 
     Further a protrusion part having a wave shape may be formed on a bottom surface of the second damping part such that the bottom surface of the second damping part line- or point-contacts a protrusion of the pawl lever. 
     A protrusion part with an embossed shape may be formed on a bottom surface of the second damping part such that the bottom surface of the second damping part point-contacts a rounded upper end of the pawl lever. 
     An another exemplary embodiment of the present invention provides the single complex type damper comprising: a striker damping part which provides damping force in response to the striker at the moment of surface-contacting the striker which is locked to the claw; and a pawl lever damping part which is formed to face downward at a lower end which is integrally formed by being extended from the striker damping part so as to give damping force to the pawl lever which rotates together with the pawl. 
     The single complex type damper formed to have a shape of “ ”, may further comprise: a first damping part which respectively protrude toward the striker from inner surface of the striker damping part so as to give damping force to the striker; and a second damping part which protrude toward the pawl lever from lower surface of the pawl lever damping part so as to respectively give damping force to the pawl lever. 
     A protrusion part having a wave shape may be formed on a bottom surface of the second damping part such that the bottom surface of the second damping part line- or point-contacts a protrusion of the pawl lever. 
     A protrusion part with an embossed shape may be formed on a bottom surface of the second damping part such that the bottom surface of the second damping part point-contacts a rounded upper end of the pawl lever. 
     Further the single complex type damper may comprise a notch part formed between the striker damping part and the pawl lever damping part. 
     In a further exemplary embodiment the present invention includes a damping device for a door latch of an automobile, comprising a single complex type damper which is provided to a base plate of a door latch of an automobile door to perform damping function to dampen shocks of both a striker and a pawl lever, the single complex type damper comprising: a striker damping part which provides damping force in response to impact of the striker, the striker damping part including a first damping part protruding toward the striker from inner surface of the striker damping part; a pawl lever damping part integrally extending from lower portion of the striker damping part to have a shape of “ ,” and formed to face downwardly so as to give damping force to the pawl lever which rotates together with the pawl, including a second damping part protruding toward the pawl lever from bottom surface of the pawl lever damping part; and a notch part formed between the striker damping part and the pawl lever damping part so as to prevent cracks. 
     The protrusion part having a wave shape may be formed on a bottom surface of the second damping part such that the bottom surface of the second damping part line- or point-contacts a protrusion of the pawl lever. 
     Further the protrusion part with an embossed shape may be formed on a bottom surface of the second damping part such that the bottom surface of the second damping part point-contacts a rounded upper end of the pawl lever. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other features of the present invention will now be described in detail with reference to certain exemplary embodiments thereof illustrated the accompanying drawings which are given hereinbelow by way of illustration only, and thus are not limitative of the present invention, and wherein: 
         FIG. 1  is a drawing showing a door latch assembly with single complex type damper of an automobile according to an embodiment of the present invention; 
         FIG. 2  and  FIG. 3  are drawings showing mount positions of a door latch assembly with single complex type damper of an automobile according to an embodiment of the present invention; 
         FIG. 4  and  FIG. 5  are perspective views of a door latch assembly with single complex type damper of an automobile according to an embodiment of the present invention; 
         FIG. 6A  and  FIG. 6B  are perspective views of a damping member of a door latch assembly with single complex type damper of an automobile according to an embodiment of the present invention; 
         FIG. 7  is a drawing showing operating state of a door latch assembly with single complex type damper of an automobile according to an embodiment of the present invention; and 
     
    
    
     In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing. 
     
       
         
           
               
             
               
                   
               
               
                 &lt;Representative reference numerals&gt; 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                   
                 100: single complex type damper 
                 110: striker damping part 
               
               
                   
                 111: first damping part 
                 120: pawl lever damping part 
               
               
                   
                 121: second damping part 
                 122, 122′: protrusion part 
               
               
                   
                   
               
            
           
         
       
     
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated in the accompanying drawings and described below. While the invention will be described in conjunction with exemplary embodiments, it will be understood that present description is not intended to limit the invention to those exemplary embodiments. On the contrary, the invention is 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. 
     Exemplary embodiments of the present invention will hereinafter be described in detail with reference to the drawing. 
       FIG. 1  is a drawing showing a door latch assembly with single complex type damper of an automobile according to an embodiment of the present invention,  FIG. 2  and  FIG. 3  are drawings showing mount positions of a door latch assembly with single complex type damper of an automobile according to an embodiment of the present invention, and  FIG. 4  and  FIG. 5  are perspective views of a door latch assembly with single complex type damper of an automobile according to an embodiment of the present invention. 
       FIG. 6A  and  FIG. 6B  are perspective views of a damping member of a door latch assembly with single complex type damper of an automobile according to an embodiment of the present invention. 
     Referring to  FIG. 1  to  FIG. 5 , a claw  11  is coupled to a front surface of a base plate  10  of a door latch which is provided to a door of an automobile to be rotatable selectively in an open or close direction around a first hinge  11   a , and a pawl which rotates around a second hinge  12   a  to maintain the latch state of the claw  11  by a return spring  14  is positioned below the claw  11  at a front surface of a base plate  10 . 
     The claw  11  comprises a first claw portion  113 , a second claw portion  114 , and a locking groove  112  wherein the locking groove  112  is positioned between the first claw portion  113  and the second claw portion  114  to receive one end of a striker  15  as explained later. 
     In addition, a pawl lever  13  formed at the rear surface of the base plate  10  and positioned co-axially with the second hinge  12   a  is integrally coupled to the pawl  12  together by rivets so as to rotate together with the rotation of the pawl  12 . 
     The pawl lever  13  comprises a protrusion  131  which protrudes upwards from a distal end portion of the pawl lever  13  substantially in parallel to rotational trajectory of the pawl lever  13 . The pawl lever  13  when a door handle is operated in order to release locking of the door, rotates together by rotations of other levers which are formed in a link structure thereby performing function of releasing lock of the claw  11  by the pawl  12 . 
     A single complex type damper  100  is provided at the rear surface of the base plate  10  so as to perform damping function for shocks occurred by impacts of both the pawl lever  13  and the striker  15 . 
     As an exemplary embodiment of the present invention, the single complex type damper  100  includes striker damping part  110 , notch part  115 , and pawl lever damping part  120 . 
     The striker damping part  110  provides damping force in response to impact of the striker  15  at the moment that the striker  15  is locked to the claw  11  in case that the door is closed i.e., when the striker  15  enters into the full latch position (as shown in  FIG. 7D ) from the half latch position (as shown in  FIG. 7C ). 
     The pawl lever damping part  120  extends integrally from lower portion of the striker damper  110  and faces the protrusion  131  of the pawl lever  13  downward at a lower distal end so as to give damping force to the pawl lever  13  which rotates together with the pawl  12 . 
     The notch part  115  is formed between the striker damping part  110  and the pawl lever damping part  120  and prevent cracks which may occur therebetween and thus increases durability of the single complex type damper  100 . 
     The single complex type damper  100 , as shown in  FIG. 1  is located backward the claw  11  with respect to the first hinge  11   a  to be fixed to a rear surface of the base plate  10  and is formed to have a shape of “ .” 
     The single complex type damper  100  further includes a first damping part  111  and a second damping part  121  wherein the first damping part  111  protrudes from inner surface of the striker damping part  10  in direction to the striker  15  and the second damping part  121  protrudes in direction to the pawl lever  13  from lower surface of the pawl lever damping part  120  downwardly so as to respectively give damping force to the striker  15  and the pawl lever  13 . 
     Accordingly, the single complex type damper  100  can reduce contact noises and shocks which occur in opening or closing operations of the striker  15  and the pawl  12 . 
     In particular, as shown in  FIG. 6B , the second damping part  121  of the pawl lever damping part  120  further includes a protrusion part  122 . The protrusion part  122  has a wave shape formed on a bottom surface of the second damping part  121  and thus the protrusion part  122  line-or point-contacts the protrusion  131  of the pawl lever  13 . 
     Accordingly, contact noise can be reduced, compared to the surface-contact between the conventional pawl and the pawl damper. 
     As an another exemplary embodiment of the structure for the point-contact of the second damping part  121 , the wave shape can be replaced with an embossed shape on a bottom surface of the second damping part  121 , thereby achieving the point-contact effectively. 
     Operations of a damping device according to an embodiment of the present invention will be explained hereinafter with reference to the drawings. 
       FIG. 7  is a drawing illustrating operating state of a door latch assembly with single complex type damper of an automobile according to an embodiment of the present invention. 
     Firstly, the close locking state of the door will be explained. 
     The striker  15  is fixed to a vehicle body and elements and the claw  11  and the pawl  12  are mounted to the door for opening or closing operation. However, for convenience of explanations, it will be assumed that the striker  15  moves relatively to the claw  11 . 
     Accordingly, as the door is to be closed, the striker  15  moves into the locking groove  112  of the claw  11  and one side of the striker  15  pushes the first claw portion  113  of claw  11 , the pawl  12  and the pawl lever  13  are released downwardly from the claw  11  as shown in  FIGS. 7A and 7B . 
     As the first and second claw portions  113  and  114  pass the pawl  12  in contact with the pawl  12 , the pawl  12  and the pawl lever  13  rotate upwardly with respect to the second hinge  12   a  by the return spring  14 , the protrusion  131  of the pawl lever  13  gives impact force to the second damping part  121  of the single complex type damper  100  as shown in  FIGS. 7C-7D  but the impact is absorbed by the second damping part  121  in line or point contact. 
     As the second claw portion  114  further moves to the first claw portion  113 , the claw  11  further rotates around the first hinge  11   a  to be in the full latch state, and then the striker  15  gives impact force to the first damping part  11  of the striker damping part  110  of the single complex type damper  100 . However, the impact is absorbed by the first damping part  111  and at this time, the pawl  12  and the pawl lever  13  is continuously supported by return force of the returning spring. 
     Meanwhile, in case that the door is opened by the operation of the door handle, the pawl lever  13  rotates elastically downwardly by the rotation of another lever (not shown) to release the restriction force of the claw  11  and thus the striker  15  and the claw  11  become disengaged so that the door can be opened. 
     While the door is opened or closed as such, damping between the striker  15 , the pawl  12  and the damping member are stably performed so that noise occurring due to the operations of the striker  15  and the pawl  12  can be minimized while the door is being closed. 
     As described above, according to a damping device for a door latch of an automobile according to the present invention, manufacturing cost can be reduced by decrease of the number of the damping member and manufacturing processes and closing sound of the door can be improved. 
     While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.