Abstract:
A collapsible vehicle door pull handle comprises two separate pieces joined together by a break away feature. This arrangement allows the pull handle to be strong when the occupant pulls the vehicle door closed, but allows deflection because of the break away feature during a side impact event. The collapsible vehicle door pull handle comprises a handle, a base, an attachment member fitted to one of the handle and the base, and an elastic deformable portion having a keyway for receiving and holding the attachment member with the attachment portion being on the other of the base and the handle. A molded handle might enclose part or all of the handle.

Description:
CROSS-REFERENCE TO RELATED 
       [0001]    This application is a divisional application of U.S. patent application Ser. No. 13/037,469 (filed on Mar. 1, 2011). 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates generally to a door trim pull handle for use with a vehicle. More specifically, the present invention relates to a collapsible door trim pull handle which is strong and durable under normal use but which will demonstrate compromised lateral stiffness in the event of a side impact. 
       BACKGROUND OF THE INVENTION 
       [0003]    It is known in vehicles to provide an armrest in a door having an integrated pull handle (also known as a grab handle) to allow the occupant to pull the door shut. The pull handle is designed to withstand tens of thousands of pulls over its working life and, accordingly, must be very strong. 
         [0004]    Known pull handles are typically of one-piece design to meet requirements of strength and durability. Door pull handles are designed to meet specific deflection (flexing) requirements during a side impact event to minimize vehicle-inward movement of the handle in a side impact event while at the same time providing to the user a solid feel. Because the position of the pull handle is near the location of the seated occupant, it is somewhat challenging to satisfy the force vs. deflection requirements established for occupant safety while at the same time satisfying requirements of pull strength durability. 
         [0005]    Some efforts have been made to overcome the problems of known pull cup designs. The most common solution to improving deflection of the pull handle is to remove structure. This is achieved by forming notches or grooves (devices designed to weaken the part) into the pull handle to initiate flex and fracture. However, this approach weakens the pull handle and adversely affects durability. In addition, the flexing or fracturing itself is difficult to predict and as a result often these features do not behave as predicted, resulting in additional changes late in the program development cycle. 
         [0006]    A less complex and more predictable solution to the problems of known pull cup/grab handle designs is to simply move the pull handle away from the occupant. While improving deflection this approach negatively affects ergonomics since the handle must be placed too far forward for the comfort of the occupant. In addition, this arrangement may reduce or eliminate package space for window and door controllers. 
         [0007]    Accordingly, as in so many areas of vehicle design, there is room for improvement in the art of pull handle construction. 
       SUMMARY OF THE INVENTION 
       [0008]    The disclosed invention provides an alternative arrangement to known vehicle door pull handle designs. The disclosed invention specifically provides a vehicle door pull handle which can deflect a greater amount with less force thereby improving occupant safety without compromising durability. 
         [0009]    According to the disclosed invention, two separate pieces are joined together by a break away feature. This arrangement allows the pull handle to be strong when the occupant pulls the vehicle door closed, but allows deflection because of the break away feature during a side impact event. 
         [0010]    Particularly, the pull handle of the disclosed invention comprises a handle and a base. The two parts are fitted together by a post on one of the handle or the base and a keyway for receiving and holding the post being formed in the other of the base or the handle. According to this arrangement the handle and the base may be moved toward one another on deformation of the deformable portion during a side impact event. 
         [0011]    The attachment member includes a post having a pair of opposed flat surfaces and a pair of opposed curved surfaces. The keyway includes a channel which terminates into a post retaining area. The post retaining area is wider than said channel. The channel is defined by a pair of opposed walls. The post retaining area is defined by a curved wall. 
         [0012]    Other advantages and features of the invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    For a more complete understanding of this invention, reference should now be made to the embodiments illustrated in greater detail in the accompanying drawings and described below by way of examples of the invention wherein: 
           [0014]      FIG. 1  illustrates a perspective view of the assembled collapsible door trim pull handle of the disclosed invention enclosed within a door handle; 
           [0015]      FIG. 2  illustrates an elevational view of the assembled collapsible door trim pull handle of  FIG. 1  illustrated in its attached position to a door inner sheet metal panel; 
           [0016]      FIG. 3  illustrates a top view showing the assembly of the disclosed invention in its normal assembled position; and 
           [0017]      FIG. 4  is a perspective view of the collapsible door trim pull handle shown in  FIG. 1  but illustrating the handle spaced apart from the base in pre-assembled alignment; 
           [0018]      FIG. 5  illustrates a detailed view of the method of attaching the handle to the base by fitting the post of the handle into the keyway of the base; 
           [0019]      FIG. 6  illustrates the assembly shown in  FIG. 3  but collapsed after the application of a side impact force; 
           [0020]      FIG. 7  illustrates the assembly shown in  FIG. 2  but after the application of a side impact force; 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0021]    In the following figures, the same reference numerals will be used to refer to the same components. In the following description, various operating parameters and components are described for different constructed embodiments. These specific parameters and components are included as examples and are not meant to be limiting. 
         [0022]    With reference to  FIG. 1 , a collapsible door trim pull handle assembly, generally illustrated as  10 , is shown in perspective view. The collapsible door trim pull handle assembly  10  is illustrated within a molded handle assembly illustrated as “H”. It is to be understood that the shape and configuration of both the collapsible door trim pull handle assembly and the molded handle assembly are for illustrative purposes only and both may be modified without deviating from the invention as disclosed and claimed. In  FIG. 2  the collapsible door trim pull handle assembly  10  is shown from a side elevational view. In  FIG. 3  a plan view of the assembled collapsible door trim pull handle assembly  10  is shown while in  FIG. 4  the collapsible door trim pull handle assembly  10  is shown before assembly. 
         [0023]    Referring to  FIGS. 1 through 4 , the collapsible door trim pull handle assembly  10  comprises a handle assembly  12  and a base assembly  14 . The handle assembly  12  and the base assembly  14  are preferably composed of a substantially rigid polymerized material, such as a carbon-reinforced plastic could be used, although a metal could be used as well either alone or in conjunction with one or more plastic components. 
         [0024]    The handle assembly  12  comprises a handle bar  16  connecting a first side handle bracket  18  and a second side handle bracket  18 ′. The first side handle bracket  18  has a first attachment member  20  attached thereto and the second side handle bracket  18 ′ has a second attachment member  20 ′ (shown in shadow lines) attached thereto. 
         [0025]    The base assembly  14  comprises an anchoring plate  22  for attachment to a door inner sheet metal panel  24  (shown in  FIGS. 2 and 3 ). Attachment of the anchoring plate  22  to the door inner sheet metal panel  24  may be made by any number of known arrangements, including mechanical fasteners (not shown) fitted through holes  26  and  26 ′. The anchoring plate  22  connects a first side base bracket  28  and a second side base bracket  28 ′. The first side base bracket  28  includes a first keyway  30  and the second side base bracket  28 ′ has a second keyway  30 ′. 
         [0026]    It is to be understood that while the disclosed invention is illustrated and discussed herein as having the attachment members  20  and  20 ′ being fitted to the first side handle bracket  18  and the second side handle bracket  18 ′ respectively and as having the keyways  30  and  30 ′ being formed in the first side base bracket  28  and the second side base bracket  28 ′ respectively, this arrangement is not intended as being limiting. As an alternative, the attachment posts could be fitted to the side base brackets and the keyways could be formed in the side handle brackets. 
         [0027]    The keyways  30  and  30 ′ are formed so as to strategically engage the posts  20  and  20 ′ respectively. Particularly, and using the keyway  30  as an example as shown in  FIG. 4  and with it being understood that the keyway  30 ′ has the same configuration, the keyway  30  includes a ramped portion  32  and a narrowed portion  34  formed between a first flat surface  36  contiguous with the ramped portion  32  and a second flat surface  38  which is formed at the end of a cantilevered arm  40 . The narrowed portion  34  is narrower than a rounded post holding portion  42  defined in part by the cantilevered arm  40 . 
         [0028]    The keyways  30  and  30 ′ work in conjunction with the attachment members  20  and  20 ′. Particularly, the attachment members  20  and  20 ′ are constructed so as to cooperate with the keyways  30  and  30 ′ respectively. Using the first attachment member  20  as an example as shown in  FIG. 5  and with it being understood that the second attachment member  20 ′ has the same configuration, the attachment member  20  includes a cap  44  and a post  46  (shown in broken lines in  FIG. 5 ). The post  46  has two opposed flat surfaces  50  and  50 ′ and two opposed curved surfaces  48  and  48 ′. The two opposed flat surfaces  50  and  50 ′ define a width that is narrow enough to pass between the first flat surface  36  and the second flat surface  38  of the narrowed portion  34 . However, the two opposed curved surfaces  48  and  48 ′ define a width that is wider than the space defined between the first flat surface  36  and the second flat surface  38 . The two opposed flat surfaces  50  and  50 ′ are perpendicular to the long axes of the first side handle bracket  18  and a second side handle bracket  18 ′ respectively. 
         [0029]    Accordingly, to attach the handle assembly  12  to the base assembly  14  the installer first rotates the handle assembly  12  to about a 90° angle relative to the base assembly  14 . In this position the two opposed flat surfaces  50  and  50 ′ are in alignment with the first flat surface  36  and the second flat surface  38  of the narrowed portion  34 . Thus positioned, the installer can pass the post  46  through the narrowed portion  34  and into the rounded post holding portion  42 . Once so positioned, the installer can rotate the handle assembly  12  such that the first side handle bracket  18  and the second side handle bracket  18 ′ are in axial alignment with the first side base bracket  28  and the second side base bracket  28 ′, thus locking the handle assembly  12  with the base assembly  14 . 
         [0030]    During the course of its life, a door trim pull handle is designed to withstand tens of thousands of pulls with the maximum pull force being hundreds of Newtons. Conversely, during a side impact event the maximum force on the door trim pull handle needs to be much less than the hundreds of Newtons of the maximum pull force. The disclosed and described invention allows the handle to collapse, keeping force upon the occupant low. Particularly, when the vehicle occupant pulls on the collapsible door trim pull handle assembly  10  when closing the vehicle door (not shown), the handle assembly  12  and the base assembly  14  function as an integral component thus allowing the occupant to apply considerable force to the pull handle assembly. However, in the event of a side impact, the arrangement of the disclosed invention minimizes the impact of the collapsible door trim pull handle assembly  10  upon the occupant because of its ability to collapse. This situation is particularly shown in  FIGS. 6 and 7  in which a force has been applied to the collapsible door trim pull handle assembly  10  via the vehicle door (not shown). As the collapsible door trim pull handle assembly  10  moves vehicle inward toward the occupant (not shown), the handle assembly  12  impacts the occupant but the vehicle-inward movement of the handle assembly  12  is halted upon initial impact even as the base assembly  14  continues its vehicle-inward movement. This result is due to the designed-in and allowed deformation of the cantilevered arm  40  when the attachment member  20  is pushed against it with the vehicle-inward movement of the base assembly  14 . Because of the relatively narrow construction of the cantilevered arm  40  deformation occurs before deformation of the post  46 . Additional deformation mechanisms may be provided to the cantilevered arm  40 , such as a weakened, thinned, or notched construction. 
         [0031]    The foregoing discussion discloses and describes exemplary embodiments of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the true spirit and fair scope of the invention as defined by the following claims.