Weather strip having variable length holding lip

A climate strip includes a trim physique getting a normally 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 physique.

The weather strip is mounted on the car physique such that the trim physique is held by a flange supplied at a periphery of a door opening of a motor vehicle. The climate strip is formed by extrusion molding such that the length of the holding lip is altered in a stepped manner in accordance with the thickness of the flange.

Commonly, a climate strip, or the like, is offered on a periphery of a door opening of a motor car, such as an automobile. The climate strip consists of a trim body getting a substantially U-shaped cross section, and a seal portion that has a hollow shape and projects from the trim body. The trim physique is fitted onto a flange offered at the periphery of the door opening so as to be held in position. A metal insert is embedded in the trim physique. Holding lips are formed integrally on inside surfaces of sidewalls of the trim body, such that each and every holding lip extends toward the inside of the trim body. When the weather strip is mounted on the car physique, the trim body is fitted onto the flange and is retained in position fundamentally utilizing the elastic force applied from the holding lips. At the time of closing the door, an edge portion of the door comes in contact with and deforms the seal portion to thereby provide a seal in between the door and the vehicle body. Most of or the whole length of the weather strip therefore constructed is formed by so-referred to as extrusion molding.

In the meantime, the thickness of the flange to which the climate strip is attached can vary from one particular portion thereof to an additional. In this case, if the size (length) of each holding lip is constant over the entire circumference of the climate strip, a load (which will be referred to as "insertion load") required for inserting the flange into the trim body becomes big in a portion exactly where the thickness of the flange is huge, resulting in a lowered effectiveness in attaching the climate strip to the automobile physique. In a portion exactly where the thickness of the flange is smaller, on the other hand, the weather strip might be simply detached from the flange due to reasonably little elastic force applied from the holding lips to the flange.

For stopping the above-described troubles, extrusion molding for forming the weather strip might be carried out such that the projection length of each and every holding lip continuously varies in accordance with alterations in the thickness of the flange. Yet, in the case exactly where the thickness of the flange regularly alterations, it is crucial to often change the length of every single holding lip as properly. Therefore, the manage of the length of the holding lips may well become difficult, which may well outcome in an enhance in the expense. In addition, a desired projection length of the holding lip can't be achieved if the length of the holding lip is changed with delay in relation to the thickness of the flange during extrusion molding. For avoiding this, subsequently, the extrusion speed wants to be lowered to some extent, which, in turn, may well outcome in a deterioration in the productivity or production effectiveness. Nevertheless further, a particular degree of variations normally occur in the longitudinal position of the climate strip relative to the flange of the car physique through production and mounting of the strip on the flange. If such variations take place, the significance of precisely changing the length of the holding lip in accordance with the thickness of the flange could possibly be lost. Namely, in the presence of the variations as described above, the weather strip could possibly incorporate a portion or portions in which the holding lip does not have an intended or desired projection length. In this case, the insertion load could possibly be undesirably big.