Weatherstrip of expandable width

Abstract: A one-piece weatherstrip which is adapted for engagement over an end flange (12) of a vehicle is disclosed. The belt weatherstrip includes a one-piece core member (20) which has a backing leg (22), an intermediate leg (24) and a show surface leg (26) which generally form a U-shaped member having a width which fits over the end flange (12) of a vehicle. An elastomeric coating (32) is extruded onto portions of the core member (20) for providing at least one sealing lip (34) extending from the core member. A plurality of perforations (28) formed in the intermediate leg (24) allow expansion in the width of the perforated leg (24) such that the width of the weatherstrip may be varied along the length of the weatherstrip during forming of the weatherstrip. In accordance with the method steps of the present invention a weatherstrip core blank (58) is first provided and thereafter a plurality of perforations (28) are formed in the blank along a longitudinal portion of the blank. A core shape is formed from the blank by stretch bending the blank along the central longitudinal portion having the plurality of perforations for varying the cross-sectional dimension at the plurality of perforations thereby facilitating formation of a weatherstrip having a varying width and cross-sectional dimension.

Description: This invention relates to a belt weatherstrip for a vehicle and to a method of forming it. More particularly, the present invention relates to a belt weatherstrip which seals the portion of a vehicle between the sliding glass window and the show surface of a vehicle door, for instance. Belt weatherstrips of the past have generally been utilized to weather-strip sheet metal flange areas of a vehicle. For instance, a vehicle door has a spot welded end flange connecting the outer show surface portion with the inner frame portion of the door. Such a flange is commonly provided for forming the window aperture. Such weatherstrips commonly include a sealing lip for sealing and stripping water off the glass window and an overhanging elastomeric strip portion which rests on the belt shelf of the outer show surface of the car door in order to prevent water from entering the flange area. It is desired in such constructions to provide a transitional surface of the weather strip which may include either a coloured elastomeric strip or chrome strip or the like which aesthetically matches the finishing contours of the vehicle surface, in order to produce a matched fit. In many vehicle designs a belt shelf having a transition edge is formed near the door flange which becomes a transition point from the weatherstrip show surface to the vehicle door show surface. Such edges may vary in width along the length of the door and thus have varying curvatures to which it is desirable to match a weatherstrip. It is desired that such a belt weatherstrip will blend in with the design of the vehicle body and form a generally continuous surface at the transition edge of the vehicle door. This was accomplished in some past constructions by manufacturing a two-piece belt weatherstrip in accordance with the particular tolerances of the particular application as in Figure 5 of US-A-4949507. For instance, in prior constructions a belt weatherstrip core and show surface were manufactured to a particular specification of the transition edge to be matched. After the manufacture of this portion a separately manufactured glass sealing lip member was attached by staples or the like to the first portion and the belt weatherstrip was then assembled onto the vehicle end flange. One possible solution is shown in Figures 1 to 4 of United States Patent US-A-4949507 entitled "One-Piece Expandable Weatherstrip" which allows extra material for variation of the width of the weatherstrip. The prior two-piece belt weatherstrips were relatively expensive to manufacture since the tooling and manufacturing equipment used must be changed for each particular vehicle model design. Additionally, such prior two-piece belt weatherstrip constructions required a two-step process for attaching the sealing lip portion to the belt weatherstrip core portion, thus adding to the cost of labour involved in assembling the belt weatherstrip. According to one aspect of the present invention, there is provided a method of forming a one-piece core of a weatherstrip having non-uniform cross-sectional dimensions, by providing a weatherstrip core blank, and forming the core shape from the blank; characterised in that the method includes:- forming a plurality of perforations in the blank along a longitudinally extending, transversely intermediate portion of the blank; and forming a core shape of the weatherstrip from the blank with stretch bending of the blank along the intermediate longitudinal portion having the plurality of perforations, the plurality of perforations allowing expansion in the width of the intermediate portion thereby facilitating formation of regions of non-uniform cross-sectional dimension. Preferably the plurality of perforations are a plurality of parallel cuts in the core blank. Preferably the cuts are angled at less than 90°C to a longitudinal axis of the core blank. Preferably the cuts are sized such that the cuts extend substantially across the entire width of the intermediate portion. According to another aspect of the present invention, there is provided a belt weatherstrip adapted for engagement over an end flange of a vehicle, the belt weatherstrip comprising: a one-piece core member including a backing leg, an intermediate leg and a show surface leg generally forming a U-shaped member having a width for fitting over the end flange; and an elastomeric coating extruded onto at least portions of the core member and providing at least one sealing lip extending from the core member; characterised in that a plurality of perforations is formed in the intermediate leg whereby the perforations allow expansion in the width of the perforated intermediate leg such that the width may be varied during forming of the weatherstrip to provide a better final fit with respect to the vehicle. Preferably the plurality of perforations are elongated cuts in the intermediate leg. The present invention makes it possible to provide a one-piece belt weatherstrip of the present invention which can be stretch formed to vary in its width such that it is adaptable to varying width belt shelfs. Such a construction allows reduced costs in tooling and manufacture of the part resulting in more efficient utilization of resources and cost savings in both manufacture and sales of the part. For a better understanding of the present invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings:- Figure 1 is a perspective view of a belt weatherstrip in accordance with the present invention partially in cross-section, located on a flange; Figure 2 is a top plan view showing the expanded cuts in the intermediate leg in phantom; Figure 3 is a plan view of a blank formed with cuts therein, for use in the method of the present invention; and Figure 4 is a detailed sectional view of the belt weatherstrip of Figure 1. In accordance with the present invention there is provided a belt weatherstrip, generally shown at 10, which is adapted for engagement over an end flange, generally indicated at 12, of a door 14 of a vehicle. In particular, referring to Figure 1, the vehicle door 14 includes a belt shelf portion 16 and has a curvature across its length as shown by the curvature at the surface 18 wherein the belt weatherstrip 10 contacts the door 14. The belt weatherstrip of the present invention includes a one-piece core member generally indicated at 20 which includes a back leg 22, an intermediate leg 24 and an outer show surface leg 26. The legs 22, 24 and 26 form a generally U-shaped member which has a width for fitting over the end flange 12. A plurality of perforations 28 are provided in the intermediate leg 24. Perforations 28 allow expansion of the width of the intermediate leg 24 as the width may be varied by stretch bending during forming of the weatherstrip to provide a better final fit with respect to the edge 18. The intermediate leg 24 having the perforations 28 therein is shown in more detail in Figures 2 and 3. Referring to Figure 3 the cuts are incorporated first into a core blank 52. The cuts 28 are provided in a central longitudinal portion of the blank 52 and are merely elongated cuts in the core blank 52 in their initial form. In a preferred embodiment, these cuts are formatted in a parallel fashion and at an angle to the longitudinal axis of the core blank or final weatherstrip. The cuts are sized such that they do not extend beyond the width of the intermediate leg and preferably the cuts extend substantially across the entire width of the intermediate leg 24. However, the perforations may be otherwise sized depending on the desired amount of stretch bending to be accomplished. Thereafter, the core is formed into the shape of the weatherstrip from the core blank and during formation is stretch bent about the central longitudinal section to the final curvaceous form as shown in Figure 2. It will be readily noted in Figure 2 that the cuts 28 in the central portion of the weatherstrip, wherein the width has been expanded, have allowed expansion and have been widened such that they appear as elliptical openings 28a in the intermediate leg 24. Thus, the perforations or cuts 28 and 28a in the expanded form allow for formation of the varying cross-sectional dimension along the width of the weatherstrip during forming for providing proper contours with respect to a final desired application in a vehicle. Referring now to Figure 4, in a preferred embodiment the leg 22 has an over-turned lower end 30. An elastomeric coating 32 is provided over the leg 22 and the end 30. A sealing lip 34 of the type which seals and strips water from the vehicle window is extruded along with the coating 32 and includes flocking 36 thereon as is common in such applications. A lip portion 38 is extruded and extends into the flangeway area of the intermediate leg 24 to overlap in the area of the perforations 28. This lip portion is spaced from the intermediate leg 24 such that the perforations are not visible in the final assembly. The show surface leg 26 also includes an overturned flange 40 which provides for a good seal on the show surface of the vehicle. Also provided is a dove railed portion 42 over which a stainless cap 44 may be fitted. Extruded coatings such as shown at 46 and 48 may be applied onto the core for various aesthetic effects as desired. The upper extrusion 48 is overlapped by the lip 38 in the construction of the present invention. The lip 38 is slidable along upper extrusion 48 for providing a suitable transition between the two surfaces irrespective of the width of the intermediate leg 24. This covers the cuts 28 on the intermediate leg 24 from view and allows the width of leg 24 to be carried without affecting the aesthetic appearance of this area of the weatherstrip 10. A means for attachment, such as retention clips 50, is provided for attaching the weatherstrip of the present invention onto the flange 12. Such clips are known in the art and are described in the aforementioned U.S. Patent US-A-4949507. Of course, other means for locking the belt weatherstrip onto an end flange may be incorporated herein without deviating from the scope of the present invention. In accordance with the method aspect of the present invention a one-piece weatherstrip, which may be adapted for varying cross-sectional widths and thereby accommodating a curvaceous belt shelf, is provided. The method includes the steps of first providing a weatherstrip core blank. A plurality of perforations are then provided on the blank along a longitudinal portion of the blank by way of die cutting or the like. A core shape of the weatherstrip is formed from the blank with the intermediate leg formed by stretch bending to vary the width of the weatherstrip and thereby accommodate the final dimensions of the belt shelf. The plurality of perforations are preferably configured on the blank as a plurality of parallel elongated cuts along a longitudinal axis. The cuts allow more malleability at the intermediate leg to facilitate stretch bending of the leg along its width. This adjusts the width of the weatherstrip to accommodate the belt shelf contour. Preferably, the elastomeric coatings for forming sealing lips and the like are extruded onto the blank prior to roll forming and stretch bending of the blank to form the final weatherstrip. Of course, the coatings could be extruded after forming without deviating from the scope of the present invention.

Claims: A method of forming a one-piece core (20) of a weatherstrip (10) having non-uniform cross-sectional dimensions, by providing a weatherstrip core blank (52), and forming the core shape from the blank (52); characterised in that the method includes:- forming a plurality of perforations (28) in the blank (52) along a longitudinally extending, transversely intermediate portion (24) of the blank (52); and forming a core shape of the weatherstrip (10) from the blank (52) with stretch bending of the blank (52) along the intermediate longitudinal portion (24) having the plurality of perforations, the plurality of perforations (28) allowing expansion in the width of the intermediate portion (24) thereby facilitating formation of regions of non-uniform cross-sectional dimension. A method according to claim 1, wherein the plurality of perforations (28) is a plurality of parallel cuts (28) in the core blank (52). A method according to claim 1 or 2, wherein the cuts (28) are angled at less than 90°C to a longitudinal axis of the core blank (52). A method according to claim 1, 2 or 3, wherein the cuts (28) are sized such that the cuts extend substantially across the entire width of the intermediate portion (24). A belt weatherstrip (10) adapted for engagement over an end flange (12) of a vehicle, the belt weatherstrip (10) comprising: a one-piece core member (20) including a backing leg (22), an intermediate leg (24) and a show surface leg (26) generally forming a U-shaped member having a width for fitting over the end flange (12); and an elastomeric coating (32) extruded onto at least portions of the core member (20) and providing at least one sealing lip (34) extending from the core member (20); characterised in that a plurality of perforations (28) is formed in the intermediate leg (24) whereby the perforations (28) allow expansion in the width of the perforated intermediate leg (24) such that the width of the weatherstrip (10) may be varied during forming of the weatherstrip to provide a better final fit with respect to the vehicle. A belt weatherstrip according to claim 5, wherein the plurality of perforations (28) are elongated cuts in the intermediate leg (24). A belt weatherstrip according to claim 6, wherein the elongated cuts (28) are parallel to one another. A belt weatherstrip according to claim 7, wherein the cuts (28) are angled at less than 90°C with respect to the longitudinal direction of the belt weatherstrip. A belt weatherstrip according to claim 8, wherein the cuts (28) are sized such that they extend substantially across the entire width of the intermediate leg. A belt weatherstrip according to any one of claims 5 to 9, wherein the elastomeric portion (32) includes a lip (38) which covers the plurality of perforations (28) but is spaced from the intermediate leg.

Inventors: LARSEN DOUGLAS CHARLES, LARSEN, DOUGLAS CHARLES
Applicants: STANDARD PRODUCTS CO, THE STANDARD PRODUCTS COMPANY
Application year: 1992
Main classification: B60J10
IPC codes: B21D31, B21D35, B29C47, B60J10, B60R13, B29K105, B29K21, B29D99