Patent Publication Number: US-2023135801-A1

Title: Grommet

Description:
TECHNICAL FIELD 
     The present disclosure relates to a grommet. 
     BACKGROUND 
     For example, a grommet disclosed in Patent Document 1 is configured to be attached to an attachment hole formed in a vehicle body panel to prevent water from entering between the attachment hole and a wire harness that is passed through the attachment hole. To describe in detail, the grommet includes an annular seal portion that is configured to be in tight contact with a circumferential portion of the attachment hole of the vehicle body panel to prevent water and the like from entering the attachment hole via the seal portion. 
     PRIOR ART DOCUMENT 
     Patent Document 
     
         
         Patent Document 1: JP 2018-046683 A 
       
    
     SUMMARY OF THE INVENTION 
     Problems to be Solved 
     The inventors of the present application conducted studies on a configuration of a seal portion that can be used in a grommet as described above to improve water sealing property. 
     It is an object of the present disclosure to provide a grommet that can improve water sealing property. 
     Means to Solve the Problem 
     A grommet according to the present disclosure is a grommet that is attached to an attachment hole of a vehicle body panel through which a wire harness is passed, the grommet including: an opposing portion that opposes a circumferential portion of the attachment hole of the vehicle body panel; and an annular seal portion that is provided in the opposing portion and is brought into tight contact with the vehicle body panel, wherein the seal portion includes: an annular first lip portion that extends from the opposing portion toward the vehicle body panel; and an annular second lip portion that extends from the opposing portion toward the vehicle body panel and is provided radially inward of the first lip portion, the first lip portion is inclined radially outward toward a tip end of the first lip portion, and the second lip portion is inclined radially inward toward a tip end of the second lip portion. 
     Effect of the Invention 
     According to the present disclosure, it is possible to provide a grommet that can improve water sealing property. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of a grommet according to an embodiment. 
         FIG.  2    is an exploded perspective view of the grommet according to the embodiment. 
         FIG.  3    is a cross-sectional view of the grommet according to the embodiment. 
         FIG.  4    is an enlarged cross-sectional view of a relevant part of the grommet according to the embodiment. 
         FIG.  5    is an enlarged cross-sectional view of a relevant part of the grommet that has been attached to a vehicle body panel. 
     
    
    
     DETAILED DESCRIPTION TO EXECUTE THE INVENTION 
     Description of Embodiment of the Present Disclosure 
     First, aspects of an embodiment according to the present disclosure will be listed and described. 
     [1] A grommet according to the present disclosure is a grommet that is attached to an attachment hole of a vehicle body panel through which a wire harness is passed, the grommet including: an opposing portion that opposes a circumferential portion of the attachment hole of the vehicle body panel; and an annular seal portion that is provided in the opposing portion and is brought into tight contact with the vehicle body panel, wherein the seal portion includes: an annular first lip portion that extends from the opposing portion toward the vehicle body panel; and an annular second lip portion that extends from the opposing portion toward the vehicle body panel and is provided radially inward of the first lip portion, the first lip portion is inclined radially outward toward a tip end of the first lip portion, and the second lip portion is inclined radially inward toward a tip end of the second lip portion. 
     With this configuration, the first lip portion and the second lip portion are inclined so as to be spaced apart from each other in the radial direction. Accordingly, when the first lip portion and the second lip portion are brought into tight contact with the vehicle body panel, the space surrounded by the first lip portion, the second lip portion, and the vehicle body panel is brought into a negative pressure (substantially vacuum), and it is therefore possible to cause the seal portion to adhere by suction to the vehicle body panel. When the seal portion adheres by suction to the vehicle body panel, a gap is unlikely to be formed between the vehicle body panel and the seal portion, as a result of which, the water sealing property of the seal portion is improved. 
     [2] In a state in which the grommet is attached to the vehicle body panel, an outer surface of the first lip portion and an outer surface of the second lip portion are spaced apart from the opposing portion. 
     With this configuration, it is possible to prevent the first lip portion and the second lip portion adhering by suction to the vehicle body panel from being compressed and collapsed by the opposing portion. As a result, it is possible to appropriately keep the state in which the first lip portion and the second lip portion adhere by suction to the vehicle body panel. 
     [3] The vehicle body panel is a panel that separates an inside from an outside of a cabin of the vehicle, and the grommet is configured such that, in a state in which the grommet is attached to the vehicle body panel, the first lip portion and the second lip portion are in tight contact with an inside surface of the vehicle body panel. 
     With this configuration, the seal portion adhering by suction to the vehicle body panel can appropriately prevent water that has entered from the outside to the inside of the cabin of the vehicle via the attachment hole despite the fact that the outside surface of the vehicle body panel is likely to get wet. 
     [4] The grommet includes: a grommet main body that includes the opposing portion and the seal portion; and an inner member that is made of a material that is more rigid than the grommet main body. The inner member includes: an engagement piece that is engaged with a surface of the vehicle body panel that is opposite to a surface to which the seal portion is brought into tight contact with at a circumferential edge of the attachment hole; and a flange portion that is held by the opposing portion of the grommet main body. In a state in which the engagement piece is engaged with and attached to a circumferential edge of the attachment hole, the seal portion is compressed between the vehicle body panel and the flange portion. With this configuration, the seal portion is compressed between the vehicle body panel and the flange portion of the inner member, and it is therefore possible to appropriately cause the seal portion to adhere by suction to the vehicle body panel. 
     [5] The opposing portion includes an intermediate portion that is provided between the flange portion and the vehicle body panel. The second lip portion extends from the intermediate portion toward the vehicle body panel. The intermediate portion is formed such that a thickness of the intermediate portion increases in a direction in which the flange portion and the vehicle body panel oppose each other as the intermediate portion extends toward a base end portion of the second lip portion. With this configuration, the rigidity of the intermediate portion provided between the flange portion and the vehicle body panel can be ensured. 
     Detailed Description of Embodiment of the Present Disclosure 
     A specific example of a grommet according to the present disclosure will be described below with reference to the drawings. It is to be noted that the present invention is not limited to examples given below, the scope of the present invention is indicated by the appended claims, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced within the scope of the present invention. The term “perpendicular” used in the present disclosure does not only strictly mean “perpendicular”, but also encompasses a meaning that can be deemed as “perpendicular” as long as the advantageous effects of the present invention can be achieved. 
     A grommet  10  according to an embodiment of the present disclosure shown in  FIGS.  1  and  3    is attached to an attachment hole Pa formed in a vehicle body panel P that separates the inside from the outside of the cabin of the vehicle to ensure water sealing property between the attachment hole Pa and a wire harness W that is passed through the attachment hole Pa. In addition, the grommet  10  also functions to protect the wire harness W that is passed through the attachment hole Pa. 
     The vehicle body panel P is a panel that separates the inside from the outside (for example, the engine room) of the cabin of the vehicle. The grommet  10  according to the present embodiment is attached to the attachment hole Pa from the inside of the cabin of the vehicle. The wire harness W includes at least one electrical wire. 
     The grommet  10  includes an inner member  11  that is inserted into the attachment hole Pa of the vehicle body panel P and a grommet main body  12  that is attached to the inner member  11 . The grommet main body  12  is made of a highly flexible material (for example, an elastomer such as EPDM (ethylene propylene rubber)). The inner member  11  is made of a material (for example, a synthetic resin material such as PP (polypropylene)) that is more rigid than the grommet main body  12 . 
     (Inner Member  11 ) 
     As shown in  FIGS.  2  and  3   , the inner member  11  includes a tubular portion  13 . The tubular portion  13  has a shape that conforms to the shape of an opening of the attachment hole Pa when viewed from the axial direction of the tubular portion  13 . In the description given below, a direction that is orthogonal to the central axis L of the tubular portion  13  will be referred to as “radial direction”. A plurality of engagement pieces  14  are formed around the tubular portion  13 . In the present embodiment, three engagement pieces  14  are provided substantially equidistantly in the circumferential direction of the tubular portion  13 . 
     Each engagement piece  14  is configured to bend in the radial direction of the tubular portion  13 . Each engagement piece  14  includes a protruding portion  15  that protrudes radially outward. The protruding portion  15  of each engagement piece  14  is configured to be capable of engaging with the circumferential edge of the attachment hole Pa in a direction opposite to an insertion direction D in which the grommet  10  is inserted (see  FIG.  5   ). In the present embodiment, the protruding portion  15  engages with the outside surface of the vehicle body panel P. 
     The inner member  11  includes a flange portion  16  that extends radially outward from the tubular portion  13 . The flange portion  16  is formed at one end portion of the tubular portion  13  in the axis L direction (a rear end portion in the insertion direction D). The flange portion  16  has a flat plate-like shape that is substantially perpendicular to the central axis L. The flange portion  16  has an outer shape larger than the attachment hole Pa of the vehicle body panel P when viewed in the axis L direction. In a state in which the grommet  10  is attached to the attachment hole Pa, the flange portion  16  is located on the inside of the vehicle body panel P. 
     (Grommet Main Body  12 ) 
     As shown in  FIGS.  2  and  3   , the grommet main body  12  includes a base portion  21  that closes the attachment hole Pa. The base portion  21  has a shape larger than the attachment hole Pa when viewed in the axis L direction. The base portion  21  includes, at the outer circumferential edge portion of the base portion  21 , an opposing portion  22  that opposes the circumferential portion of the attachment hole Pa of the vehicle body panel P in the axis L direction. The opposing portion  22  extends along the entire outer circumferential edge portion of the base portion  21  in the circumferential direction. 
     The base portion  21  of the grommet main body  12  includes a cylindrical insertion portion  23  into which the wire harness W is inserted. The insertion portion  23  covers the outer circumference of the wire harness W. Also, the wire harness W is inserted through the insertion portion  23  while the water sealing property is ensured. In the present embodiment, the wire harness W is inserted into the attachment hole Pa such that the wire harness W is inclined relative to the axis L direction, and thus the insertion portion  23  is inclined relative to the axis L direction to conform to the insertion direction in which the wire harness W is inserted. Also, in a state in which the grommet main body  12  and the inner member  11  are attached, the insertion portion  23  of the grommet main body  12  is inserted through the inner circumference of the tubular portion  13 . 
     Also, the grommet main body  12  according to the present embodiment includes an umbrella-shaped covering portion  24  that extends from the outer circumferential edge of the base portion  21  toward the outer circumference of the grommet main body  12 . The covering portion  24  is configured to close an opening of an insulator (sound insulating member) (not shown) that is attached to the inside surface of the vehicle body panel P. 
     As shown in  FIGS.  3  and  4   , the opposing portion  22  of the base portion  21  includes a holding portion  25  for holding the flange portion  16  of the inner member  11 . The holding portion  25  is formed in an annular shape about the axis L direction. The holding portion  25  is shaped to have a recess extending radially outward, and the flange portion  16  is fitted into the recess. Specifically, the holding portion  25  is configured to cover both surfaces of the flange portion  16  in the axis L direction as well as a radially outer surface of the flange portion  16 . 
     (Seal Portion  26 ) 
     On one surface of the opposing portion  22  in the axis L direction, or to be more specific, on a surface of the opposing portion  22  on the forward side in the insertion direction D (the surface that opposes the vehicle body panel P), a seal portion  26  that is brought into tight contact with the circumferential portion of the attachment hole Pa of the vehicle body panel P is formed. The seal portion  26  has an annular shape that is larger than the attachment hole Pa and extends along the circumferential edge of the attachment hole Pa. In the present embodiment, the seal portion  26  is configured to be in tight contact with the inside surface of the vehicle body panel P. 
     As shown in  FIGS.  4  and  5   , the seal portion  26  includes a first lip portion  31  and a second lip portion  32 . The first lip portion  31  and the second lip portion  32  each extend from the opposing portion  22  toward the vehicle body panel P. The second lip portion  32  has an annular shape that is larger than the attachment hole Pa and extends along the circumferential edge of the attachment hole Pa. The first lip portion  31  has an annular shape that is larger than the second lip portion  32 . That is, the second lip portion  32  is provided radially inward of the first lip portion  31 . Also, the first lip portion  31  and the second lip portion  32  oppose each other in the radial direction. 
     The first lip portion  31  is inclined radially outward toward the tip end of the first lip portion  31  (or in other words, as the distance from the opposing portion  22  increases). Likewise, the second lip portion  32  is inclined radially inward toward the tip end of the second lip portion  32  (or in other words, as the distance from the opposing portion  22  increases). Also, the seal portion  26  according to the present embodiment includes a crossing portion  33  where a base end portion of the first lip portion  31  and a base end portion of the second lip portion  32  cross each other. Accordingly, a cross section of the seal portion  26  taken along the axis L direction has a substantially V shape that is open toward the vehicle body panel P. Also, in a state in which the grommet  10  is attached to the vehicle body panel P, the inner surfaces (mutually opposing surfaces) of the first lip portion  31  and the second lip portion  32  are brought into tight contact with the circumference of the attachment hole Pa on the inside surface of the vehicle body panel P (see  FIG.  5   ). 
     The opposing portion  22  includes an intermediate portion  22   a  that is provided between the seal portion  26  and the flange portion  16  in the axis L direction. A surface of the intermediate portion  22   a  that opposes the second lip portion  32  in the axis L direction forms an inclined surface  22   b . The inclined surface  22   b  is inclined toward the second lip portion  32  (the vehicle body panel P) in the axis L direction as the inclined surface  22   b  extends radially outward. That is, the intermediate portion  22   a  is formed such that the thickness of the intermediate portion  22   a  increases in the axis L direction (the thickness of the intermediate portion  22   a  in a direction in which the flange portion  16  and the vehicle body panel P oppose each other) as the intermediate portion  22   a  extends toward the base end portion of the second lip portion  32 . With this configuration, the rigidity of the intermediate portion  22   a  can be ensured. 
     The operations of the present embodiment will be described. 
     When the grommet  10  is inserted into the attachment hole Pa of the vehicle body panel P in the insertion direction D from the inside of the cabin of the vehicle, as shown in  FIG.  5   , the first lip portion  31  and the second lip portion  32  are deformed such that the inner surfaces of the first lip portion  31  and the second lip portion  32  abut against the vehicle body panel P and come closer to the opposing portion  22 . Then, the intermediate portion  22   a  of the opposing portion  22  and the seal portion  26  are compressed between the flange portion  16  and the vehicle body panel P in the axis L direction. Also, in this state, the protruding portion  15  of each engagement piece  14  of the inner member  11  engages with the circumferential edge of the attachment hole Pa. 
     At this time, the seal portion  26  that includes the first lip portion  31  and the second lip portion  32  adheres by suction to the vehicle body panel P. That is, a space S surrounded by the first lip portion  31 , the second lip portion  32 , and the vehicle body panel P is brought into a negative pressure (substantially vacuum), as a result of which, the first lip portion  31  and the second lip portion  32  adhere to the vehicle body panel P by the action of the external pressure. 
     As described above, in a state in which the seal portion  26  adheres by suction to the vehicle body panel P, the first lip portion  31  and the second lip portion  32  are in sealing contact with the vehicle body panel P. For this reason, it is very unlikely that a gap is formed between the first lip portion  31  and the vehicle body panel P and between the second lip portion  32  and the vehicle body panel P, and the vehicle body panel P, and thus the water sealing property of the seal portion  26  is improved. 
     Also, the grommet  10  according to the present embodiment is attached to the vehicle body panel P from the inside of the cabin of the vehicle, and the seal portion  26  of the grommet main body  12  is brought into tight contact with the inside surface of the vehicle body panel P. It is the outside surface of the vehicle body panel P that is most likely to get wet, and thus water may enter from the outside of the cabin of the vehicle to the inner circumferential side of the seal portion  26  via the attachment hole Pa. For this reason, the seal portion  26  according to the present embodiment is required to have water sealing performance of preventing water on the inner circumferential side of the seal portion  26  from flowing to the outer circumferential side of the seal portion  26 . In the specification of the present application, a radially outward direction in which the seal portion  26  prevents the flow of water will be referred to as “water sealing direction”. 
     Here, as a comparative example, a configuration will be considered in which the second lip portion  32  is inclined radially outward (inclined in the same direction as the first lip portion  31 ). In this case, the seal portion  26  does not adhere by suction to the vehicle body panel P, and, in addition thereto, both the first lip portion  31  and the second lip portion  32  are inclined in the water sealing direction (radially outward), and it is therefore difficult to prevent water on the inner circumferential side of the seal portion  26  from flowing to the outer circumferential side of the seal portion  26 . 
     In this regard, with the grommet  10  according to the present embodiment, due to the first lip portion  31  and the second lip portion  32 , the seal portion  26  adheres by suction to the vehicle body panel P, and it is therefore possible to prevent water on the inner circumferential side of the seal portion  26  from flowing to the outer circumferential side of the seal portion  26 . 
     Also, in a state in which the first lip portion  31  and the second lip portion  32  adhere by suction to the vehicle body panel P, an outer surface  31   a  of the first lip portion  31  and an outer surface  32   a  of the second lip portion  32  are spaced apart from the opposing portion  22 . With this configuration, it is possible to prevent the first lip portion  31  and the second lip portion  32  adhering by suction to the vehicle body panel P from being compressed and collapsed by the opposing portion  22 , as a result of which, the state in which the first lip portion  31  and the second lip portion  32  adhere by suction to the vehicle body panel P can be appropriately maintained. 
     Also, the seal portion  26  according to the present embodiment is configured such that the outer surface  31   a  of the first lip portion  31  and the outer surface  32   a  of the second lip portion  32  are spaced apart from the opposing portion  22 , from which it can be seen that the configuration is not intended to ensure water sealing property by compressing and collapsing the first lip portion  31  and the second lip portion  32  in the insertion direction D. Accordingly, with the grommet  10  according to the present embodiment, an insertion force required to attach the grommet  10  to the attachment hole Pa can be minimized, which contributes to improving the ease of attachment of the grommet  10 . 
     The advantageous effects of the present embodiment will be described. 
     (1) The first lip portion  31  and the second lip portion  32  are inclined so as to be spaced apart from each other in the radial direction. With this configuration, the space S surrounded by the first lip portion  31 , the second lip portion  32 , and the vehicle body panel P when the first lip portion  31  and the second lip portion  32  are brought into tight contact with the vehicle body panel P is brought into a negative pressure (substantially vacuum), and it is therefore possible to cause the seal portion  26  to adhere by suction to the vehicle body panel P. When the seal portion  26  adheres by suction to the vehicle body panel P, a gap is unlikely to be formed between the vehicle body panel P and the seal portion  26 , as a result of which, the water sealing property of the seal portion  26  is improved. 
     (2) The grommet  10  is configured such that, in a state in which the grommet  10  is attached to the vehicle body panel P, the outer surface  31   a  of the first lip portion  31  and the outer surface  32   a  of the second lip portion  32  are spaced apart from the opposing portion  22 . With this configuration, it is possible to prevent the first lip portion  31  and the second lip portion  32  adhering by suction to the vehicle body panel P from being compressed and collapsed by the opposing portion  22 . As a result, the state in which the first lip portion  31  and the second lip portion  32  adhere by suction to the vehicle body panel P can be appropriately maintained. 
     (3) The vehicle body panel P is a panel that separates the inside from the outside of the cabin of the vehicle, and the grommet  10  is configured such that, in a state in which the grommet  10  is attached to the vehicle body panel P, the first lip portion  31  and the second lip portion  32  are in tight contact with the inside surface of the vehicle body panel P. With this configuration, the seal portion  26  adhering by suction to the vehicle body panel P can appropriately prevent water that has entered from the outside to the inside of the cabin of the vehicle via the attachment hole Pa despite the fact that the outside surface of the vehicle body panel P is likely to get wet. 
     (4) The grommet  10  includes: a grommet main body  12  that includes an opposing portion  22  and a seal portion  26 ; and an inner member  11  that is made of a material that is more rigid than the grommet main body  12 . The inner member  11  includes: an engagement piece  14  that is engaged with a surface of the vehicle body panel P that is opposite to a surface with which the seal portion  26  is brought into tight contact at the circumferential edge of the attachment hole Pa; and a flange portion  16  that is held by the opposing portion  22  of the grommet main body  12 . Also, in a state in which the engagement piece  14  is engaged with and attached to the circumferential edge of the attachment hole Pa, the seal portion  26  is compressed between the vehicle body panel P and the flange portion  16 . With this configuration, because the seal portion  26  is compressed between the vehicle body panel P and the flange portion  16  of the inner member  11 , it is possible to cause the seal portion  26  to appropriately adhere by suction to the vehicle body panel P. 
     (5) The opposing portion  22  includes an intermediate portion  22   a  that is provided between the flange portion  16  and the vehicle body panel P, and the second lip portion  32  extends from the intermediate portion  22   a  toward the vehicle body panel P. The intermediate portion  22   a  is formed such that the thickness of the intermediate portion  22   a  increases in a direction (the axis L direction) in which the flange portion  16  and the vehicle body panel P oppose each other as the intermediate portion  22   a  extends toward a base end portion of the second lip portion  32 . With this configuration, the rigidity of the intermediate portion  22   a  provided between the flange portion  16  and the vehicle body panel P can be ensured. 
     (6) The seal portion  26  includes a crossing portion  33  where a base end portion of the first lip portion  31  and a base end portion of the second lip portion  32  cross each other. With this configuration, the first lip portion  31  and the second lip portion  32  are provided adjacent to each other in the radial direction, as a result of which, with the first lip portion  31  and the second lip portion  32 , it is possible to cause the seal portion  26  to appropriately adhere by suction to the vehicle body panel P. 
     The present embodiment can be carried out by making medications as described below. The present embodiment and variations given below can be combined as appropriate unless they are technically contradictory to each other.
         The materials for forming the grommet main body  12  and the inner member  11  are not limited to those described in the embodiment given above, and may be changed as appropriate according to the configuration.   The configuration, such as the shape, of the seal portion  26  that includes the first lip portion  31  and the second lip portion  32  is not limited to that described in the embodiment given above, and may be changed as appropriate. In order to cause the first lip portion  31  and the second lip portion  32  to appropriately adhere by suction to the vehicle body panel P, it is preferable that the lengths of the first lip portion  31  and the second lip portion  32  are not extremely different. Specifically, it is preferable that the length of one of the first lip portion  31  and the second lip portion  32  is longer than the half length of the other of the first lip portion  31  and the second lip portion  32 .   In the embodiment given above, the base end portion of the first lip portion  31  and the base end portion of the second lip portion  32  cross each other, but the configuration is not limited thereto, and the base end portion of the first lip portion  31  and the base end portion of the second lip portion  32  may be radially spaced apart from each other.   The configuration, such as the shape, of the grommet main body  12  is not limited to that described in the embodiment given above, and, for example, the covering portion  24  may be omitted from the grommet main body  12  of the embodiment given above. Also, the insertion portion  23  may be configured to extend along the axis L direction (the direction in which the attachment hole Pa extends).   The embodiment given above is applied to a grommet  10  that is attached to the attachment hole Pa from the inside of the cabin of the vehicle, but may be applied to a grommet that is attached to the attachment hole Pa from the outside of the cabin of the vehicle.   The embodiment given above is applied to a grommet  10  that includes a grommet main body  12  that is made of a highly flexible material such as an elastomer and an inner member  11  that is made of a material that is more rigid than the grommet main body  12 , but is also applicable to, for example, a grommet that is made only of a highly flexible material.       

     The present disclosure encompasses implementation examples given below. 
     Reference numerals of the constituent elements of the embodiment are assigned to facilitate the understanding of the implementation examples and thus are not construed as limiting. 
     [Additional Statement 1] 
     A grommet ( 10 ) according to an implementation example of the present disclosure includes: 
     a grommet main body ( 12 ) including an annular seal portion ( 26 ) that is configured to be in tight contact with a first surface of a vehicle body panel (P) that has an attachment hole (Pa) and an opposing portion ( 22 ) that opposes an annular region that extends along a circumferential edge of the attachment hole (Pa); and 
     an inner member ( 11 ) that includes a tubular portion ( 13 ) that is disposed on an inner circumferential side of the seal portion ( 26 ), 
     wherein the seal portion ( 26 ) includes: 
     first and second lip portions ( 31  and  32 ) that extend from the opposing portion; and 
     a crossing portion ( 33 ) where base end portions of the first and second lip portions ( 31  and  32 ) cross each other, 
     a tip end of the first lip portion ( 31 ) may be located on an inner circumferential side relative to the crossing portion ( 33 ), and 
     a tip end of the second lip portion ( 32 ) may be located on an outer circumference side relative to the crossing portion ( 33 ). 
     [Additional Statement 2] 
     In one or more implementation examples of the present disclosure, the tubular portion ( 13 ) may include: 
     a flange ( 16 ) that protrudes from a first end of the tubular portion ( 13 ) in an axial direction of the tubular portion ( 13 ); and 
     a plurality of engagement pieces ( 14 ) that protrude from a second end of the tubular portion ( 13 ) in the axial direction of the tubular portion ( 13 ). 
     [Additional Statement 3] 
     In one or more implementation examples of the present disclosure, the plurality of engagement pieces ( 14 ) may include three or more engagement pieces ( 14 ) that are provided at intervals along the circumferential edge of the attachment hole (Pa). 
     [Additional Statement 4] 
     In one or more implementation examples of the present disclosure, the first surface may be an inside surface of the vehicle body panel (P), and the vehicle body panel (P) may include a second surface that is opposite to the first surface. 
     [Additional Statement 5] 
     In one or more implementation examples of the present disclosure, each of the plurality of engagement pieces ( 14 ) may include a protrusion that is configured to engage with the second surface at a tip end thereof. 
     [Additional Statement 6] 
     In one or more implementation examples of the present disclosure, the grommet main body ( 12 ) may further include: 
     a plate-like base portion ( 21 ) that covers the attachment hole (Pa); and 
     a tubular insertion portion ( 23 ) that extends through the base portion ( 21 ), and through which a wire harness (W) is passed. 
     [Additional Statement 7] 
     In one or more implementation examples of the present disclosure, the insertion portion ( 23 ) includes: a first portion that extends along an outer surface of the base portion; and a second portion that protrudes from the base portion ( 21 ) to an inner circumferential side of the tubular portion ( 13 ), and 
     the second portion may be inclined relative to the base portion ( 21 ) and the first portion. 
     [Additional Statement 8] 
     In one or more implementation examples of the present disclosure, the grommet main body ( 12 ) may further include an annular covering portion ( 24 ) that extends from an outer edge of the opposing portion ( 22 ). 
     [Additional Statement 9] 
     In one or more implementation examples of the present disclosure, a leading end of the covering portion ( 24 ) may include a base end that connects to the opposing portion ( 22 ) and a tip end that is located on an outer circumferential side relative to the base end. 
     [Additional Statement 10] 
     In one or more implementation examples of the present disclosure, the seal portion ( 26 ) may be configured such that a closed spaced surrounded by the first lip portion ( 31 ), the second lip portion ( 32 ), and the first surface is defined when the first and second lip portions ( 31  and  32 ) are brought into tight contact with the first surface. 
     [Additional Statement 11] 
     In one or more implementation examples of the present disclosure, the crossing portion ( 33 ) may be spaced apart from the first surface when the first and second lip portions ( 31  and  32 ) are brought into tight contact with the first surface. 
     [Additional Statement 12] 
     In one or more implementation examples of the present disclosure, the first and second lip portions ( 31  and  32 ) may elastically deform such that the tip ends of the first and second lip portions ( 31  and  32 ) are spaced apart from each other when the seal portion ( 26 ) is brought into tight contact with the first surface. 
     It should be apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the technical concept of the present invention. For example, some of the components described in the embodiment (or one or more aspects thereof) may be omitted or may be used in combination. The scope of the present invention should be determined with reference to the appended claims, along with the full scope of equivalents to which the claims are entitled. 
     LIST OF REFERENCE NUMERALS 
     
         
         
           
               10  Grommet 
               11  Inner member 
               12  Grommet main body 
               13  Tubular portion 
               14  Engagement piece 
               15  Protruding portion 
               16  Flange portion 
               21  Base portion 
               22  Opposing portion 
               22   a  Intermediate portion 
               22   b  Inclined surface 
               23  Insertion portion 
               24  Covering portion 
               25  Holding portion 
               26  Seal portion 
               31  First lip portion 
               31   a  Outer surface 
               32  Second lip portion 
               32   a  Outer surface 
               33  Crossing portion 
             D Insertion direction 
             L Central axis 
             P Vehicle body panel 
             Pa Attachment hole 
             S Space 
             W Wire harness