Abstract:
A vehicle occupant safety apparatus ( 10 ) for inserting into and covering an opening ( 22 ) of an instrument panel ( 12 ) comprises an air bag module ( 14 ). The air bag module ( 14 ) has an air bag ( 50 ), which is inflatable through the opening ( 22 ) in the instrument panel ( 12 ) for protecting a vehicle occupant during a crash condition. The apparatus ( 10 ) further comprises a door ( 16 ) for covering the opening ( 22 ) in the instrument panel ( 12 ). The door ( 16 ) is attached to the air bag module (14) and is movable relative to the air bag module ( 14 ) to locate the door ( 16 ) relative to the instrument panel ( 12 ). The door ( 16 ) and the instrument panel ( 12 ) have respective interlocking portions ( 34  and  90 ), which snap together to attach the door ( 16 ) to the instrument panel ( 12 ). The interlocking portions ( 34  and  90 ) snap together when the air bag module ( 14 ) is inserted into the opening ( 22 ) in the instrument panel ( 22 ) and the door ( 16 ) is moved relative to the air bag module ( 14 ) into a position to cover the opening ( 22 ). The interlocking portions ( 34 ) of the instrument panel ( 12 ) are deflected when the respective interlocking portions ( 34  and  90 ) of the door ( 16 ) and the instrument panel ( 12 ) snap together.

Description:
TECHNICAL FIELD 
     The present invention relates to a vehicle occupant safety apparatus and, more particularly, to a vehicle occupant safety apparatus with a deployment door that attaches to a vehicle instrument panel. 
     BACKGROUND OF THE INVENTION 
     A known vehicle occupant safety apparatus includes an air bag module having an inflatable air bag, an inflator for inflating the air bag, and a reaction can that receives the air bag and the inflator. The air bag module is mounted within an instrument panel of a vehicle. The known vehicle occupant safety apparatus has a deployment door or cover that is attached to the reaction can and hides the air bag, inflator, and reaction can from view when the module is installed in the instrument panel. Thus, the deployment door covers an opening in the instrument panel through which the air bag module is installed and through which the air bag expands upon inflation. The deployment door is attached to the reaction can such that the door can “float” or move relative to the reaction can. After the air bag module is installed in the instrument panel, the deployment door can be properly oriented relative to the instrument panel and then fixed to the instrument panel. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a vehicle occupant safety apparatus. The apparatus comprises an air bag module having an air bag that is inflatable through an opening of the instrument panel for helping to protect a vehicle occupant during a crash condition. The apparatus further comprises a door for covering the opening in the instrument panel. The door is attached to the air bag module and is movable relative to the air bag module to position the door relative to the instrument panel. The door and the instrument panel have respective interlocking portions that snap together to attach the door to the instrument panel when the air bag module is inserted into the opening in the instrument panel and the door is moved relative to the air bag module. The interlocking portions of the instrument panel are deflected when the respective interlocking portions of the door and the instrument panel snap together. 
     The present invention also is directed to a method of mounting a vehicle occupant safety apparatus in an opening of an instrument panel. In the method, a door is attached to an air bag module in a manner such that the door is movable relative to the air bag module. The air bag module is inserted into the opening in the instrument panel. The door is moved relative to the air bag module and relative to the instrument panel so that respective interlocking portions of the instrument panel and the door snap together. The interlocking portions of the instrument panel are deflected when the interlocking portions of the door and the instrument panel snap together. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing and other features of the present invention will become apparent to those skilled in the art to which the present invention relates upon reading the following description with reference to the accompanying drawings, in which: 
     FIG. 1 is a view of a vehicle occupant safety apparatus of the present invention prior to being mounted in an opening of an instrument panel; 
     FIG. 2 is a sectional view of an assembled vehicle occupant safety apparatus of the present invention inserted into and covering an opening of an instrument panel; 
     FIG. 3 is a view taken along line  3 — 3  in FIG. 1; 
     FIG. 4 is a view of the instrument panel taken along line  4 — 4  in FIG.  3  and showing a button supporting a portion of a door of the vehicle occupant safety apparatus; and 
     FIG. 5 is a view of the instrument panel taken along line  5 — 5  in FIG.  3  and showing a portion of the door of the vehicle occupant safety apparatus attached to the instrument panel. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENT 
     FIG. 1 illustrates a vehicle occupant safety apparatus  10  of the present invention prior to being mounted in an opening  22  of an instrument panel  12  of a vehicle. 
     The instrument panel  12  extends laterally in the vehicle from a location near a driver-side door (not shown) to a location near a passenger-side door (not shown). The instrument panel  12  extends vertically from a position near the steering column (not shown) to a position meeting a bottom surface of the vehicle windshield (not shown). On the driver-side of the vehicle, the instrument panel  12  includes a gauge console (not shown), generally located directly behind the steering wheel (not shown) of the vehicle. On the passenger-side of the vehicle, the instrument panel  12  includes a glove box opening  20  and an opening  22  for receiving an air bag module  14 . 
     As shown in FIGS. 1 and 3, the opening  22  for receiving the air bag module  14  is rectangular with rounded corners. The opening  22  is defined by an upper surface  24 , a lower surface  26 , a right side surface  28 , and a left side surface  30 . Both the upper surface  24  and the lower surface  26  extend horizontally. Both the right side surface  28  and left side surface  30  extend vertically and connect the upper surface  24  and the lower surface  26 . 
     The upper surface  24  forming the opening  22  in the instrument panel  12  curves slightly inwardly from the face  32  of the instrument panel  12  (FIGS.  2  and  5 ). 
     The face  32  of the instrument panel  12  faces the vehicle occupant compartment. Projecting from the upper surface  24  is a plurality of flanges  34  for connecting to a door  16 . As shown in FIGS. 1 and 3, the flanges  34  are U-shaped, and each flange  34  extends into the opening  22  of the instrument panel  12 . Each flange  34  has a main body portion  36  that is contiguous with and extends from the upper surface  24 . The main body portion  36  of each flange  34  is trapezoidal (FIG.  3 ). The main body portion  36  narrows as it extends into the opening  22  of the instrument panel  12 . A bottom surface  40  is the narrowest surface of the main body portion  36  of each U-shaped flange  34 . Two legs  42  extend downwardly from the bottom surface  40  of the main body portion  36  of the flange  34 . Each leg  42  extends from an end of the bottom surface  40 . Each leg  42  becomes wider as it extends away from the main body portion  36  of the U-shaped flange  34 . The distance between the legs of each U-shaped flange  34  decreases as the legs extend away from the main body portion  36 . 
     The U-shaped flanges  34  are molded as one piece with the instrument panel  12 . The legs  42  of the U-shaped flanges  34  are resilient and, if deflected, snap back into their original position. 
     As shown in FIGS. 1 and 3, on the right side surface  28  forming the opening  22  of the instrument panel  12  is a centrally located protrusion  46  that extends into the opening  22 . The protrusion  46  is square and has a width and a height in the range of 10-30% of the height of the right side surface  28 . The height of the right side surface  28  is the distance between the upper surface  24  and the lower surface  26  forming the opening  22  in the instrument panel. A circular bore  48  extends through the protrusion  46 . 
     The left side surface  30  forming the opening  22  of the instrument panel is a mirror image of the right side surface  28 . A centrally located protrusion  46  is disposed on the left side surface  30 . The size of the protrusion  46  on the left side surface  30  equals the size of the protrusion  46  on the right side surface  28 . Like the protrusion  46  on the right side surface  28 , a circular bore  48  extends through the protrusion  46  on the left side surface  30 . 
     As shown in FIG. 1, the lower surface  26  forming the opening  22  in the instrument panel  12  is located immediately above the glove box opening  20 . A portion of a metal reinforcement (not shown) for the instrument panel  12  is located beneath the lower surface  26  to provide support for the instrument panel  12  in the area between the two openings  20  and  22 . 
     As shown in FIG. 2, the air bag module  14  includes an air bag  50 , an inflator  52 , and a reaction can  54 . The reaction can  54  has a curved rear wall portion  56  that interconnects an upper wall portion  58  of the reaction can  54  and a lower wall portion  60  of the reaction can  54 . Two end wall portions  62 , only one of which is shown in FIG. 1, close the axial ends of the reaction can  54 . 
     The upper wall portion  58  of the reaction can  54  terminates with a hook  64 . The hook  64  extends upwardly from the terminal end of the upper wall portion  58  and extends a short distance toward the rear wall portion  56  of the reaction can  54 . In the preferred embodiment, a single hook  64  extends along the entire axial length, into the paper as viewed in FIG. 2, of the upper wall portion  58  of the reaction can  54 . 
     The lower wall portion  60  of the reaction can  54  also terminates with a hook  65 . The hook  65  extends downwardly from the terminal end of the lower wall portion  60  and extends a short distance toward the rear wall portion  56  of the reaction can  54 . In the preferred embodiment, a single hook  65  extends along the entire axial length, into the paper as viewed in FIG. 2, of the lower wall portion  60  of the reaction can  54 . 
     The reaction can  54  forms a trough shaped cavity. An opening leading into the trough shaped cavity is located between the hooks  64  and  65  and the two end portions  62  of the reaction can  54 . The inflator  52  is located within the cavity of the reaction can  54  and is fixed relative to the reaction can  54 . The inflator  52  is cylindrical and extends axially between the two end portions  62  of the reaction can  54 . A plurality of inflation fluid outlets (not shown) is formed in the cylindrical side wall of the inflator  52 . The inflator  52 , when actuated upon the occurrence of a crash condition, releases an inflation fluid that exits from the inflator  52  through the inflation fluid outlets. The inflator  52  may be any known inflator  52 . 
     The inflation fluid from the inflator  52  inflates an air bag  50 . The air bag  50 , while in an uninflated state, is retained within the trough shaped cavity of the reaction can  54 . Fasteners (not shown), such as threaded studs and nuts, secure the inflator  52  and the air bag  50  to the reaction can  54 . 
     The door  16  of the vehicle occupant safety apparatus  10  is formed as one piece, preferably from a thermoplastic material. The color and exterior texture of the door  16  may be selected to match the instrument panel  12  so that the door  16  appears as an integral part of the instrument panel  12 . 
     As shown in FIG. 2, the door  16  includes a front panel  68 . The front panel  68  forms a cover for the opening  22  of the instrument panel  12 . The front panel  68  includes an outer surface  70  and an inner surface  72 . The outer surface  70  of the front panel  68  faces the vehicle occupant. The inner surface  72  of the front panel  68  faces the front of the vehicle and includes a tear seam  74 . Preferably, the tear seam  74  extends horizontally across the front panel  68 . The tear seam  74  is rupturable under the force of the inflating air bag  50  to allow the air bag  50  to deploy through the opening  22  of the instrument panel  12  and into the vehicle occupant compartment. 
     The door  16  includes an upper portion  76  and a lower portion  78 . The tear seam  74  separates the upper portion  76  and the lower portion  78 . As shown in FIG. 2, two inwardly extending flanges  80  and  82  extend from the inner surface  72  of the front panel  68 . The inwardly extending flange  80  extends from the upper portion  76  of the door  16 , and the inwardly extending flange  82  extends from the lower portion  78  of the door  16 . Each flange  80  and  82  is located approximately one-third of the distance from an outer edge  84  of the door  16  to a vertical center  86  of the door  16 . The flanges  80  and  82  extend at an angle that is approximately perpendicular to the front panel  68  of the door  16 . 
     An elongated slot  88  extends through flange  80 . The slot  88  receives hook  64  of the reaction can  54  of the air bag module  14 . An elongated slot  89  extends through flange  82 . The slot  89  receives hook  65  of the reaction can  54  of the air bag module  14 . Each of the elongated slots  88  and  89  has a width W (FIG. 2) that is sufficiently large to allow the door  16 , when attached to the air bag module  14 , to move relative to the air bag module  14 . When attached to the air bag module  14 , the door  16  closes the opening of the trough shaped cavity formed by the reaction can  54 . 
     The upper portion  76  of the door  16  also includes a plurality of L-shaped flanges  90 , one of which is shown in FIG. 2, that extend inwardly from the inner surface  72  of the front panel  68  of the door  16 . The L-shaped flanges  90  are located near the outer edge  84  of the upper portion  76  of the door  16 , and each L-shaped flange  90  aligns with a U-shaped flange  34  extending from the instrument panel  12 . Each L-shaped flange  90  includes a base portion  92 , a neck portion  93 , and a head portion  94 . 
     The base portion  92  includes a lower surface  96  (FIG. 5) and an upper surface  98 . The upper surface  98  is nearest the outer edge  84  of the upper portion  76  of the door  16  and extends inwardly from the inner surface  72  of the front panel  68  of the door  16 . The lower surface  96  of the base portion  92  extends inwardly from the inner surface  72  of the front panel  68  of the door  16  and upwardly toward the upper surface  98 . The lower surface  96  extends at an angle of approximately forty-five degrees relative to the upper surface  98 . The lower surface  96  extends at this angle until extending inwardly to a location at approximately  75  percent of the inward length of the upper surface  98 . The lower surface  96  then extends parallel to the upper surface  98  the remainder of the inward length of the upper surface  98 . An end surface  95  of the base portion  92  extends perpendicular to the upper surface  98  and terminates short of the lower surface  96 . 
     The neck portion  93  extends inwardly from the base portion  92 . The neck portion includes a lower surface  97  and an upper surface  99 . The neck portion  93  has a height, defined as the distance between the lower and upper surfaces  97  and  99 , that is approximately one-half the height of the base portion  92  immediately adjacent the neck portion  93 . The lower surface  97  of the neck portion  93  aligns with and is a continuation of the lower surface  96  of the base portion  92  and extends inwardly. The upper surface  99  of the neck portion  93  also extends inwardly and is parallel to the lower surface  97  of the neck portion  93 . The neck portion  93  also has a depth, extending into the paper as viewed in FIG. 5, that is sized to snap between the legs  42  of the U-shaped flange  34 . Thus, the depth of the neck portion  93  is less than the distance between the legs  42  at a location near the main body portion  36  of a respective U-shaped flange but is greater than the distance between the legs  42  of the U-shaped flange  34  away from the main body portion  36 . 
     The head portion  94  of the L-shaped flange  90  extends inwardly from the neck portion and also extends toward the outer edge  84  of the upper portion  76  of the door  16 . The head portion  94  includes a nose portion  100 . The nose portion  100  extends outwardly over the upper surface  99  of the neck portion  93 . The nose portion  100  includes a surface  101  for locking against the main body portion  36  of the U-shaped flange  34 . Surface  101  of the nose portion  100  extends parallel to end surface  95  of the base portion  92 . The head portion  94  has a depth, again extending into the paper as viewed in FIG. 5, that is less than or equal to the depth of the neck portion  93 . 
     FIG. 1 shows two buttons  102  for mounting in the protrusions  46  that extend from the right and the left side surfaces  28  and  30  of the instrument panel  12 . The buttons  102  are independent pieces for, when inserted in the protrusions  46 , supporting a portion of the door  16 . As shown in FIG. 4, each button  102  includes a cylindrical main body portion  104 , a neck portion  106 , and a head portion  108 . 
     The cylindrical main body portion  104  of each button  102  extends for approximately sixty percent of the length of the button  102  and includes a flat circular surface  110  at one end of the main body portion  104 . The neck portion  106  extends from an end of the main body portion  104  opposite surface  110 . The neck portion  106  is approximately one-half the diameter of the main body portion  104  and extends for approximately twenty percent of the length of the button  102 . 
     The head portion  108  of the button  102  extends from the neck portion  106  on a side opposite the main body portion  104 . The head portion  108  has a hemispherical shape with a diameter equal to the diameter of the main body portion  104  of the button  102 . This results in an annular, flat surface  112  of the head portion  108  extending radially outwardly from the neck portion  106 . Four slots  114 , two of which are shown in FIG. 4, extend partially through the head portion  108 . The slots  114  extend from the outer circumference of the flat surface  112  of the head portion  108  inwardly to the diameter of the neck portion  106 . The slots  114  are spaced at 90-degree intervals from one another around the annular, flat surface  112 . The button  102  is formed as one piece from either rubber or a thermoplastic material. Thus, the head portion  108  of the button is resiliently deformable. 
     To mount the vehicle occupant safety apparatus  10  in the opening  22  of the instrument panel  12 , the door  16  is first attached to the reaction can  54 . The door  16  is attached to the reaction can  54  by inserting the hook  64  of the upper wall portion  58  of the reaction can  54  through the elongated slot  88  in the inwardly extending flange  80  of the door  16 . The door  16  is also attached to the reaction can  54  by inserting the hook  65  of the lower wall portion  60  of the reaction can  54  through the elongated slot  89  in the inwardly extending flange  82  of the door  16 . The two buttons  102  are inserted into the corresponding bores  48  in the protrusions  46  that extend from the right and the left side surfaces  28  and  30  of the instrument panel  12 . As shown in FIG. 4 with reference to one button  102 , after the head portion  108  of the button  102  is inserted through the corresponding bore  48 , the head portion  108  is located on the forward facing side of the protrusion  46  and the cylindrical main body  104  of the button  102  is located on rearward facing side of the protrusion  46 . Thus, when a button  102  is connected to the protrusion  46 , the neck portion  106  extends through the bore  48  in the respective protrusion  46  and the flat surface  110  of the main body portion  104  of the button  102  faces the vehicle occupant compartment. 
     After the buttons  102  are inserted into the bores  48  of the protrusions  46 , the air bag module  14  is inserted into the opening  22  in the instrument panel  12  and is secured the instrument panel  12 . The upper portion  76  of the door  16  is then moved relative to the air bag module  14  and relative to the instrument panel  12  to a position where the L-shaped flanges  90  of the door  16  become aligned with and snap together with the U-shaped flanges  34  of the instrument panel  12 . When snapping together, the legs  42  of each U-shaped flange  34  are deflected laterally outwardly, i.e., away from one another, as the neck portion  93  of the respective L-shaped flange  90  passes between the legs  42  to interlock with the U-shaped flange  34 . Once the neck portion  93  passes between the legs  42  of the U-shaped flange  34 , the legs  42  return to their original position to lock the neck portion between them. Also, when a U-shaped flange  34  is interlocked with an L-shaped flange  90 , as shown in FIG. 5, the bottom surface  40  of the main body portion  36  of the U-shaped flange  34  is received between the end surface  95  and the nose portion  100  of the L-shaped flange  90 . Preferably, surface  101  of the nose portion  100  of the head portion  94  of the L-shaped flange  90  abuts the main body portion  36  of the U-shaped flange  34 . 
     Then, the lower portion  78  of the door  16  is moved so that a portion of the inner surface  72  of the front panel  68  of the door  16  rests on the flat surface  110  of each button  102 . As shown in FIG. 2, when the door  16  is resting on the flat surfaces  110  of the buttons  102 , the lower portion  78  of the door  16  extends over the lower surface  26  of the instrument panel  12  forming the opening  22 . Fasteners  116  are then inserted into the lower portion  78  of the door  16  to connect the lower portion  78  of the door  16  to the instrument panel  12 . Preferably the fasteners  116  are self-tapping and secure the lower portion  78  of the door  16  to the reinforcement (not shown) located behind the instrument panel  12 . When the door  16  is secured to the instrument panel  12 , an interference fit exists between the upper portion  76  of the door  16  and the instrument panel  12 . The interference fit is leaves a gap of between 1 mm and 1.5 mm between the outer edge  84  of the upper portion  76  of the door  16  and the instrument panel  12  (the gap is not shown in FIG.  5 ). After installation of the fasteners  116 , the heads  118  of the fasteners  116  can be seen from within the vehicle occupant compartment. A glove box door  120  or a bezel covers the fastener heads  118  so that the heads  118  are not visible to a vehicle occupant. 
     Those skilled in the art will recognize that the illustrated air bag module  14  is for purposes of example only. Any air bag module  14  with provisions for attaching a door  16 .and allowing the door  16  to move relative to the air bag module  14  is within the scope of this invention. 
     From the above description of the invention, those skilled in the art will perceive improvements, changes and modifications. Such improvements, changes and modifications within the skill of the art are intended to be covered by the appended claims.