Low flexural modulus pattern on extruded low-friction material
A composite structure finds particular use as a weatherstrip on a motor vehicle. The weatherstrip includes a first material such as rubber, EPDM or thermoplastic that exhibits flexibility, and a second, hard, low friction material applied over portions of a surface of the rubber. In a preferred arrangement, the low friction material is coextruded with the first material in spaced rows that allow the weatherstrip to flex in regions where no second material is applied. An increased thickness of low friction material is applied thereby improving wear characteristics without impacting flexibility.
1 . A weather strip for engaging an associated sealing surface comprising:
an elongated flexible member having a first surface, at least a portion of which, is adapted for engagement with the associated window; and
the first surface including a low friction material disposed thereon in longitudinal rows such that the flexible member is capable of selective articulation along a region between the longitudinal rows.
2 . The weather strip of claim 1 wherein the flexible member is formed from an elastomeric material.
3 . The weather strip of claim 1 wherein the low friction material is one of a thermoplastic and a cross linked thermoplastic.
4 . The weather strip of claim 1 wherein the longitudinal rows are substantially parallel along the length of the flexible member.
5 . The weather strip of claim 1 wherein the low friction material extends in continuous rows along the first surface portion.
6 . The weather strip of claim 5 wherein the rows of low friction material are continuous along the elongated flexible member.
7 . The weather strip of claim 6 wherein the rows of low friction material extend outwardly from the first surface of the flexible member.
8 . The weather strip of claim 1 wherein the low friction material has a variable thickness over a lateral cross-sectional extent.
9 . The weather strip of claim 1 wherein the rows of low friction material extend over substantially all of the first surface.
10 . The weather strip of claim 1 wherein the low friction material proceeds over only the first surface portion of the flexible member.
11 . A weather strip for engaging an associated sealing surface comprising:
an elongated flexible member having a first surface adapted for sealing engagement with the associated window; and
the first surface including a low friction material of variable thickness disposed on the first surface such that the flexible member maintains flexibility between regions of thick low friction material.
12 . The weather strip of claim 11 wherein the low friction material is a thermoplastic.
13 . The weather strip of claim 11 wherein the low friction material is disposed in continuous rows extending along the length of the flexible member.
14 . The weather strip of claim 11 wherein the low friction material is disposed in segregated rows along an exterior surface of the flexible member that faces the associated glass.
15 . The weather strip of claim 11 wherein the low friction material has a maximum thickness on the order of 0.144 mm.
16 . A method of forming a weather strip comprising the steps of:
forming an elongated flexible member having a first surface; and
extruding at least first and second rows of a low friction material along the first surface in regions where the weather strip is adapted for engagement with a window surface.
17 . The method of claim 16 wherein the flexible member forming step includes the step of extruding the flexible member.
18 . The method of claim 16 wherein the flexible member forming step includes the step of co-extruding the flexible member with the low friction material.
19 . The method of claim 16 wherein the low friction material extruding step includes spacing the rows apart to allow the weather strip to articulate in regions absent of the low friction material.
20 . The method of claim 16 wherein the low friction material extruding step includes the step of continuously extruding the low friction material along an entire length of the first surface.
21 . The weather strip of claim 1 wherein the flexible member is a belt seal adapted for mounting on an associated motor vehicle.
22 . The weather strip of claim 1 wherein a glass run assembly includes a generally U-shaped channel forming a cavity adapted to receive an edge of an associated window, the flexible member including first and second lips secured to the channel and extending into the cavity, and the low friction material is provided on portions of each of the first and second lips.