Weather strip and method of manufacturing the same

Abstract

A weather strip includes a trim body having a generally U-shaped cross section, a hollow seal portion that protrudes from an outside surface of the trim body, and a holding lip formed on the trim body so as to extend from an inside surface of the trim body toward the inside of the trim body. The weather strip is mounted on the vehicle body such that the trim body is held by a flange provided at a periphery of a door opening of a motor vehicle. The weather strip is formed by extrusion molding such that the length of the holding lip is changed in a plurality of steps in accordance with the thickness of the flange.

1 . A method of manufacturing a weather strip including (a) a trim body having a generally U-shaped cross section, the trim body being adapted to be held by a flange provided at a periphery of an opening formed in a motor vehicle, (b) a hollow seal portion that protrudes from an outside surface of the trim body, the seal portion being adapted to come in contact with a closure member that closes the opening, and (c) a holding lip formed on the trim body so as to extend from an inside surface of the trim body toward the inside of the trim body, the method comprising the step of: 
 forming the weather strip by extrusion molding such that a length of the holding lip is changed in a plurality of steps in accordance with a thickness of the flange.    
   
   
       2 . The method according to  claim 1 , wherein: 
 the thickness of the flange, which varies in a longitudinal direction of the weather strip, is classified into a plurality of thickness levels each corresponding to a predetermined thickness range, and the flange is divided into a plurality of sections arranged in the longitudinal direction, based on the thickness levels; and    during the extrusion molding of the weather strip, the length of the holding lip is changed in the plurality of steps with respect to the plurality of sections of the flange.    
   
   
       3 . The method according to  claim 1 , wherein: 
 a target length of the holding lip, which is selected from a plurality of target values, is determined along the longitudinal direction of the weather strip, in accordance with the thickness of the flange that varies in the longitudinal direction of the weather strip; and    the length of the holding lip is controlled to the target length during the extrusion molding of the weather strip, such that the length of the holding lip is changed substantially at the same time that the target length is changed.    
   
   
       4 . The method according to  claim 1 , wherein the number of the plurality of steps in which the length of the holding lip is changed is set based on a difference between the maximum number and the minimum number of panels that constitute the flange.  
   
   
       5 . The method according to  claim 1 , wherein the holding lip has a distal end portion having a constant shape.  
   
   
       6 . The method according to  claim 1 , wherein the holding lip includes at least one varying-length section in which the length of the holding lip is changed from one of the plurality of steps to another, and a length of the at least one varying-length section as measured in the longitudinal direction of the weather strip is equal to or smaller than a predetermined length that is set based on variations in a longitudinal position of the weather strip relative to the flange during manufacturing and mounting of the weather strip on the flange.  
   
   
       7 . A method of manufacturing a weather strip including (a) a trim body having a generally U-shaped cross section and including an inner sidewall that faces an inside of the vehicle, an outer sidewall that faces an outside of the vehicle, and a connecting portion that connects the inner and outer sidewalls, the trim body being adapted to be held by a flange provided at a periphery of an opening formed in a motor vehicle, (b) a hollow seal portion that protrudes from an outside surface of the trim body, the seal portion being adapted to come in contact with a closure member that closes the opening, and (c) a plurality of holding lips formed on the trim body so as to extend from inside surfaces of the inner sidewall and the outer sidewall toward the inside of the trim body, the method comprising the step of: 
 classifying a thickness of the flange, which varies in a longitudinal direction of the weather strip, into a plurality of thickness levels each corresponding to a predetermined thickness range, and dividing the flange into a plurality of sections arranged in the longitudinal direction, based on the thickness levels; and    forming the weather strip by extrusion molding such that at least one of the holding lips that extend from one of the inner and outer sidewalls has a constant length, and at least one of the holding lips that extend from the other of the inner and outer sidewalls has a variable length, which is changed in the plurality of steps with respect to the plurality of sections of the flange.    
   
   
       8 . The method according to  claim 7 , wherein the number of the plurality of steps in which the length of the at least one holding lip is changed is set based on a difference between the maximum number and the minimum number of panels that constitute the flange.  
   
   
       9 . The method according to  claim 7 , wherein the at least one holding lip having a variable length has a distal end portion having a constant shape.  
   
   
       10 . The method according to  claim 7 , wherein the at least one holding lip having a variable length includes at least one varying-length section in which the length of the at least one holding lip is changed form one of the plurality of steps to another, and a length of the at least one varying-length section as measured in the longitudinal direction of the weather strip is equal to or smaller than a predetermined length that is set based on variations in a longitudinal position of the weather strip relative to the flange during manufacturing and mounting of the weather strip on the flange.  
   
   
       11 . A method of manufacturing a weather strip including (a) a trim body having a generally U-shaped cross section, the trim body being adapted to be held by a flange provided at a periphery of an opening formed in a motor vehicle, (b) a hollow seal portion that protrudes from an outside surface of the trim body, the seal portion being adapted to come in contact with a closure member that closes the opening, and (c) a holding lip formed on the trim body so as to extend from an inside surface of the trim body toward the inside of the trim body, the method comprising the step of: 
 forming the weather strip by extrusion molding such that a first length of the holding lip corresponding to at least a large-thickness section of the flange having a large thickness is made smaller than a second length of the holding lip corresponding to a small-thickness section of the flange having a small thickness, and such that a section of the weather strip in which the holding lip has the first length is made longer by a predetermined length than the large-thickness section of the flange as viewed in the longitudinal direction of the weather strip.    
   
   
       12 . The method according to  claim 11 , wherein the predetermined length is set based on variations in a longitudinal position of the weather strip relative to the flange during manufacturing and mounting of the weather strip on the flange.  
   
   
       13 . A method of manufacturing a weather strip including (a) a trim body having a generally U-shaped cross section, the trim body being adapted to be held by a flange provided at a periphery of an opening formed in a motor vehicle, (b) a hollow seal portion that protrudes from an outside surface of the trim body, the seal portion being adapted to come in contact with a closure member that closes the opening, and (c) a holding lip formed on the trim body so as to extend from an inside surface of the trim body toward the inside of the trim body, the method comprising the step of: 
 forming the weather strip by extrusion molding such that a length of the holding lip is changed along a longitudinal direction of the weather strip in accordance with a thickness of the flange so that the length of the holding lip decreases with an increase in the thickness of the flange, and such that the holding lip includes longitudinally opposite end portions having substantially the same length.    
   
   
       14 . The method according to  claim 13 , wherein: 
 the length of the holding lips is changed in a plurality of steps in accordance with the thickness of the flange so that the length of the holding lip decreases with an increase in the thickness of the flange; and    at least the longitudinally opposite end portions of the holding lip have substantially the same length that is determined based on the larger one of thickness values of corresponding portions of the flange.    
   
   
       15 - 28 . (canceled)  
   
   
       29 . A structure comprising: 
 a weather strip including (a) a trim body having a generally U-shaped cross section, the trim body being adapted to be fitted on a first predetermined portion of a flange provided at a periphery of an opening formed in a motor vehicle, (b) a hollow seal portion that protrudes from an outside surface of the trim body, the seal portion being adapted to come in contact with a closure member that closes the opening, and (c) a holding lip formed on the trim body so as to extend from an inside surface of the trim body toward the inside of the trim body; and    a covering member that is mounted on the vehicle so as to cover a second predetermined portion of the flange other than the first predetermined portion, and longitudinally opposite end portions of the weather strip,    wherein a length of the holding lip is changed along a longitudinal direction of the weather strip in accordance with a thickness of the flange so that the length of the holding lip decreases with an increase in the thickness of the flange, and    wherein the holding lip includes longitudinally opposite end portions having substantially the same length, which is determined based on the larger one of thickness values corresponding portions of the flange.    
   
   
       30 . The structure according to  claim 29 , wherein the length of the holding lip is changed in a plurality of steps in accordance with the thickness of the flange so that the length of the holding lip decreases with an increase in the thickness of the flange.  
   
   
       31 . The structure according to  claim 29 , wherein the second predetermined portion of the flange is located in a lower end portion of the opening, and the covering member comprises a scuff plate fitted on at least the second predetermined portion of the flange.  
   
   
       32 . The structure according to  claim 31 , wherein the scuff plate is provided with an engaging member with which the scuff plate is fitted on the flange, the engaging member being attached to the flange at least in the vicinity of each of the longitudinally opposite end portions of the weather strip.  
   
   
       33 . A method of manufacturing a weather strip, comprising the steps of: 
 providing an insert with a plurality of marks that are spaced at regular intervals of a predetermined length;    continuously extruding a covering material together with the insert provided with the marks, so as to provide an elongated work having a predetermined cross-sectional shape; and    cutting the work at predetermined positions after the extrusion step, based on detection of a detector capable of detecting the marks through the covering material.    
   
   
       34 . The method according to  claim 33 , wherein a cutter is used for cutting the work, and wherein the marks comprise a plurality of notches formed in the insert.  
   
   
       35 . The method according to  claim 34 , wherein the detector is disposed at a position associated with the cutter or in the vicinity of the cutter.  
   
   
       36 . The method according to  claim 33 , wherein the insert hardly expands or shrinks.  
   
   
       37 . The method according to  claim 33 , wherein: 
 the insert comprises a plurality of wings and a connecting portion that connects the wings together, the wings extending in a direction perpendicular to the longitudinal direction of the work such that a predetermined spacing is provided between adjacent ones of the wings; and    each of the marks has a width that is larger than the predetermined spacing of the wings.    
   
   
       38 . The method according to  claim 33 , wherein the work includes a lip for sealing or holding, and the lip has a variable length that varies along a longitudinal direction of the work.