Patent Abstract:
A grommet through which a long member is passed and mounted on a fixing hole of a fixing plate includes a cylindrical insertion portion, through which the long member is passed, a brim-shaped close contact portion, extending outward from the insertion portion and having a mounting groove which is mounted on an edge of the fixing hole, and a cylindrical guide portion, having a through hole to path through the long member, and concentrically connected to the insertion portion such that the guide portion is projected from the fixing plate when the grommet is mounted to the fixing plate. The guide portion is provided with a cut portion so as to accommodate a part of the long member.

Full Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates to a grommet. For example, the invention relates to a grommet that is provided between two fixing plates such as those of the body and the back door of a vehicle to protect a long member that is cabled between the two fixing plates.  
           [0002]    As shown in FIG. 5, a wire harness  103  that is cabled between a body  101  and a back door  102  of a vehicle  100  is covered with a grommet  105 .  
           [0003]    Providing the grommet  105  between the body  101  and the back door  105  and covering the wire harness  103  with the grommet  105  prevents the wire harness  103  from being exposed to outside when the back door  102  is opened.  
           [0004]    The grommet  105  has, at the two ends, a body-side fixing portion  111  to be engaged in a fixing hole  10  (see FIGS.  6 A- 6 E) of the body  101 , a door-side fixing portion  112  to be engaged in a fixing hole  107  of the back door  102  and a bellows-shaped connection pipe  113  connecting the body-side fixing portion  111  and the door-side fixing portion  112  so as to be integral with those.  
           [0005]    The body-side fixing portion  111  and the door-side fixing portion  112  are approximately identical members. In the following, only the door-side fixing portion  112  will be described (the description of the body-side fixing portion  111  will be omitted).  
           [0006]    To attach the grommet  105  to the body  101  and the back door  102 , the grommet  105  in which the wire harness  103  is fitted is inserted into the fixing hole  106  of the body  101  from inside the body  101  as shown in FIG. 6A and then taken out to the space between the body  101  and the back door  102  as shown in FIG. 6B.  
           [0007]    After a tip portion  103 A of the wire harness  103  is inserted into the fixing hole  107  of the back door  102 , the door-side fixing portion  112  is put into the space inside the back door  102  through the fixing hole  107  as shown in FIGS.  6 C- 6 E. Then, the door-side fixing portion  112  of the grommet  105  is engaged into the fixing hole  107  of the back door  102 , whereby the grommet  105  is attached to the back door  102 .  
           [0008]    As shown in FIG. 7, to allow the wire harness  103  to pass through and be held by the fixing hole  107  (see FIGS.  6 A- 6 E) of the back door  102 , the door-side fixing portion  112  of the grommet  105  is provided with an outer member  121  and an inner member  120 . The outer member  121  has a pipe-shaped insertion portion  115  that is to be inserted into the fixing hole  107  and into which the wire harness  103  can be inserted, a brim-shaped close contact portion  116  that extends outward from the insertion portion  115  and is to come into close contact with the front face of the back door  103 , a pressure contact portion  117  that is provided outside the insertion portion  115  and is to come into pressure contact with the back face of the back door  102 , and a groove  118  that is formed by the inside face of the dose contact portion  116 . The inner member  120  is generally shaped like a disc having a central opening and is inserted in the groove  118 . The inner member  120  is provided outside a pipe-shaped guide portion  119 .  
           [0009]    In general, the inner member  120  is generally elliptical in a plan view. The inner member  120  can easily be inserted into the groove  118  of the close contact portion  116  of the door-side fixing portion  112  by first inserting a portion, on its major axis  120 A, of the inner member  120  into the groove  118 .  
           [0010]    By the way, as shown in FIG. 6D, the wire harness  103  is bent so as to go over a tip portion  119 A of the guide portion  119  of the door-side fixing portion  112 . Therefore, the wire harness  103  projects from the tip portion  119 A of the guide portion  119  by a relatively large projection length L.  
           [0011]    As a result, the wire harness  103  may hit the backdoor  102  in inserting the door-side fixing portion  112  of the grommet  105  into the fixing hole  107  of the back door  102 . The work of attaching the grommet  105  to the back door  102  may take long time.  
         SUMMARY OF THE INVENTION  
         [0012]    It is therefore an object of the present invention to provide a grommet capable of preventing a wire harness from hitting a fixing plate in inserting the grommet into a fixing hole of the fixing plate.  
           [0013]    In order to achieve the above object, according to the present invention, there is provided a grommet through which a long member is passed and mounted on a fixing hole of a fixing plate, comprising;  
           [0014]    a cylindrical insertion portion, through which the long member is passed;  
           [0015]    a brim-shaped close contact portion, extending outward from the insertion portion and having a mounting groove which is mounted on an edge of the fixing hole; and  
           [0016]    a cylindrical guide portion, having a through hole to path through the long member, and concentrically connected to the insertion portion such that the guide portion is projected from the fixing plate when the grommet is mounted to the fixing plate,  
           [0017]    wherein the guide portion is provided with a cut portion so as to accommodate a part of the long member.  
           [0018]    In the grommet, the guide portion may be molded either integrally with or separately from the insertion portion and the dose contact portion.  
           [0019]    More specifically, the grommet according to the invention may be such that it is provided with an outer member having the insertion portion and the close contact portion and an inner member that is generally shaped like a disc having a central opening and can be inserted in a groove formed by the inside surface of the close contact portion, and that the inner member is provided with the guide portion.  
           [0020]    In the above configuration, the guide portion is formed with the cut portion capable of accommodating the long member at least partially. Accommodating the long member In the cut portion of the guide portion makes it possible to reduce the projection length of the long member from the top of the guide portion.  
           [0021]    Therefore, the long member is prevented from hitting the fixing plate in inserting the grommet into the fixing hole of the fixing plate.  
           [0022]    Preferably, the guide portion is shaped into an elliptical shape in a plan view, and the cut portion is provided along a major axis direction of the guide portion.  
           [0023]    In general, where the guide portion is generally elliptical in a plan view, when the long member is pulled out of the guide portion of the grommet, the long member is pulled along the major axis of the guide portion.  
           [0024]    In the above configuration, the guide portion is generally elliptical shape in a plan view and the cut portion is formed on the major axis of the guide portion. This makes it possible to easily accommodate the long member in the cut portion in pulling the long member out of the guide portion. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0025]    The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein:  
         [0026]    [0026]FIG. 1 is a side view of a grommet according to the invention;  
         [0027]    [0027]FIG. 2 is an exploded perspective view of an important part of the grommet according to the invention;  
         [0028]    [0028]FIG. 3 is a sectional view of the important part of the grommet according to the invention;  
         [0029]    [0029]FIG. 4 is a side view of an important part of the grommet according to the invention;  
         [0030]    [0030]FIG. 5 is a perspective view showing a state that a related grommet is attached to a vehicle;  
         [0031]    FIGS.  6 A- 6 E illustrate a procedure for attaching the related grommet to the vehicle.  
         [0032]    [0032]FIG. 7 is an exploded perspective view of an important part of the related grommet; and  
         [0033]    [0033]FIGS. 8A and 8B illustrate a mechanism of the related grommet.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0034]    An embodiment of the present invention will be hereinafter described with reference to FIGS.  1 - 4 . Members etc. of the following embodiment in FIGS.  1 - 4  that have the same or corresponding ones in FIG. 5 to FIG. 7 are given the same or corresponding symbols as the latter and will be described in a simplified manner or will not be described.  
         [0035]    As shown in FIG. 1, a grommet  10  according to the embodiment is composed of a body-side fixing main body  20  for allowing a wire harness (long member)  15  to pass through and be held by a fixing hole  13  formed in a fixing plate  12  of a vehicle body  11 , a door-side grommet main body  30  for allowing the wire harness  15  to pass through and be held by a fixing hole  18  formed in a fixing plate  17  of a back door  16 , and a connection member  38  that connects the body-side fixing main body  20  and the door-side grommet main body  30 .  
         [0036]    As shown in FIGS.  1 - 2  the body-side fixing main body  20  has an outer member  40  and an inner member  27 .  
         [0037]    The outer member  40  has a pipe-shaped insertion portion  21  that is to be inserted into the fixing hole  13  of the vehicle body  11  and into which the wire harness  15  can be inserted, a brim-shaped dose contact portion  22  that extends outward from the insertion portion  21  and is to come into close contact with a front face  12 A of the fixing plate  12 , a pressure contact portion  25  that is provided outside the insertion portion  21  and is to come into pressure contact with a back face  12 B of the back door  12 , and a groove  23  that is formed by an inside face  21 B of the close contact portion  21 .  
         [0038]    On the other hand, the inner member  27  is generally shaped like a disc having a central opening and is inserted in the groove  23 . The inner member  27  is connected to the outer member  40  so as to be concentric with the insertion portion  21  and extends outward from an outer circumferential face  26 A of a pipehaped guide portion  26  that projects to at least one of the spaces on the front side and the back side (in this embodiment, the back side) of the fixing plate  12 .  
         [0039]    As shown in FIG. 2, the guide portion  26  has a pipe-like shape that is generally elliptical in a plan view, and has, on the side of an open-end face  26 B and on its major axis  28 A, a cut portion  26 C capable of accommodating the wire harness  15  at least partially.  
         [0040]    The inner member  27 , which is generally elliptical in a plan view, extends from the outer circumferential face  26 A of the guide portion  26 . A plurality of (first to third) projections  29 A,  20 B, and  29 C project from a periphery  27 A of the inner member  27  in such directions as to cross the minor axis  28 B of the inner member  27 .  
         [0041]    Among the first to third projections  29 A,  20 B, and  29 C, the first and second projections  29 A and  29 B project in such directions as to also cross the major axis  28 A of the inner member  27 . In addition, the outer circumferential face  26 A of the guide portion  26  is formed with a locking claw  26 D for causing the guide portion  26  to be held by the fixing plate  12  when the locking claw  26 D is locked into the fixing hole  13  of the fixing plate  12  via the dose contact portion  22  and the pressure contact portion  25 .  
         [0042]    In general, to insert the inner member  27 , which is generally elliptical in a plan view, into the groove  23  of the close contact portion  22  of the body-side grommet main body  20 , first a portion, on its major axis  28 A, of the Inner member  27  is inserted into the groove  23  in a direction indicated by an arrow in FIG. 2.  
         [0043]    As shown in FIG. 1, the door-side grommet main body  30  has a pipe-shaped insertion portion  31  that is to be inserted into the fixing hole  18  of the back door  16  and into which the wire harness  15  can be inserted, a brim-shaped dose contact portion  32  that extends outward from the insertion portion  31  and is to come into close contact with a front face  17 A of the fixing plate  17 , a pressure contact portion  35  that is provided outside the insertion portion  31  and is to come into pressure contact with a back face  17 B of the back door  17 , and a pipe-shaped guide portion  36  that is molded integrally with the close contact portion  35  and projects to at least one of the spaces on the front side and the back side of the fixing plate  17 .  
         [0044]    The connection member  38  generally assumes a pipe-like shape so as to be able to accommodate the wire harness  15  and has a bellows like shape in detail. Therefore, the connection member  38  can be bent into a desired shape and hence the grommet  10  can easily be provided between the fixing plate  12  of the vehicle body  11  and the fixing plate  17  of the back door  16 .  
         [0045]    In the grommet  10  having the above structure, the first to third projections  29 A- 29 C which project from the periphery  27 A of the inner member  27  are wrapped with the close contact portion  22 .  
         [0046]    This allows the close contact portion  22  to have a great wrapping length W2 (see FIG. 3), whereby the dose contact portion  22  of the body-side grommet main body  20  can be prevented from being turned up.  
         [0047]    Since the only change is that the first to third projections  29 A- 29 C are provided so as to project from the periphery  27 A of the inner member  27 , the inner member  27  project only partially and the first to third projections  29 A- 29 C can be made compact.  
         [0048]    This prevents the close contact portion  22  that covers the inner member  27  from interfering with the fixing plate  12  when the body-side grommet main body  20  is caused to pass through the fixing hole  13  of the fixing plate  12 .  
         [0049]    The inner member  27  is generally elliptical in a plan view and the first to third projections  29 A- 29 C project in such directions as to cross the minor axis  28 B of the inner member  27  as shown in FIG. 2.  
         [0050]    This allows the first projection  29 A and the second projection  29 B to be inserted first Into the groove  23  in a direction indicated by an arrow in FIG. 2 when the inner member  27  is inserted into the groove  23  of the close contact portion  22 . In this manner, the inner member  27  can easily be inserted into the groove  23  of the close contact portion  22 .  
         [0051]    Since the first projection  29 A and the second projection  29 B project in such directions as to cross the major axis  28 A of the inner member  27 , both of the lengths L1 and L2 of the inner member  27  along the major axis  28 A and the minor axis  288 , respectively, can be reduced as shown in FIG. 2.  
         [0052]    Therefore, the size of the inner member  27  can be reduced, that is, it can be made compact. This prevents the close contact portion  22  of the body-side grommet main body  20  that covers the inner member  27  from interfering with the fixing plate  12  when the body-side grommet main body  20  of the grommet  10  is caused to pass through the fixing hole  13  of the fixing plate  12 .  
         [0053]    In addition, since a plurality of (three) projections, that is, the first to third projections  29 A- 29 C, are provided, a large total overlap region can be secured between the inner member  27  and the close contact portion  22 . This efficiently prevents the dose contact portion  22  of the body-side grommet main body  20  from being turned up.  
         [0054]    In the grommet  10  having the above structure, as shown in FIG. 2, the open-end face  26 B of the guide portion  26  is formed with the cut portion  26 C capable of accommodating the wire harness  15  at least partially.  
         [0055]    Accommodating the wire harness  15  in the cut portion  26 C of the guide portion  26  as shown in FIG. 4 can reduce the projection length L3 of the wire harness  15  from the open-end face  26 B of the guide portion  26 .  
         [0056]    Therefore, the wire harness  15  is prevented from hitting the fixing plate  12  when the body-side grommet main body  20  is inserted Into the fixing hole  13  of the fixing plate  12 . This makes it possible to attach the body-side grommet main body  20  of the grommet  10  to the fixing plate  12  easily without taking much time.  
         [0057]    Further, as shown in FIG. 2, the guide portion  26  is generally elliptical in a plan view and is formed with the cut portion  26 C on the major axis  28 A of the guide portion  26 . This makes it possible to accommodate the wire harness  15  in the cut portion  26 C as shown in FIG. 4 easily without taking much time in pulling the wire harness  15  out of the guide portion  26 .  
         [0058]    Although the above embodiment is directed to the case that the body-side grommet main body  20  and the door-side grommet main body  30  of the grommet  10  have different structures, the inversion Is not limited to such a case. For example, the door-side grommet main body  30  may be given the same structure as the structure of the above-described body-side grommet main body  20 .  
         [0059]    Although the above embodiment is directed to the case that the long member is the wire harness  15  and the fixing plates are parts of a vehicle, the long member is not limited to a wire harness and the fixing plates are not limited to parts of a vehicle.  
         [0060]    Although the above embodiment is directed to the case that the plurality of projections are the three projections  29 A- 29 C, the number of projections is not limited to three and may be an arbitrary number.  
         [0061]    The invention is not limited to the above-described embodiment and proper modifications, improvements, etc. are possible. The material, shape, dimensions, form, number, locations, thickness, eta of each of the grommet, fixing plates, long member, eta are not limited to those exemplified in the embodiment and may be determined arbitrarily as long as the invention can be implemented.

Technology Classification (CPC): 1