Method for Replacing a Window Pane in a Flexible Hood Cover and Replacement Pane Therefor

1. Field of the Invention

The invention relates to a method for replacing a window pane in a flexible hood cover, in particular in the folding hood of a vehicle, and to a replacement pane for such a method.

2. Description of the Prior Art

Motor vehicles having a flexible folding top or hood, so-called convertibles or cabriolets, are provided for compact stowage of the folding hood generally also with a flexible rear window pane or sheet. Said near pane is highly stressed by the operation of the hood, and the flexible transparent material, which is not as robust as a glass disc, exposed to surface damage which permanently impair the transparency of the pane.

The replacement of the panes was hitherto very troublesome because they are generally physically sewn into the hood cover or fabric in order to obtain adequate sealing against rain. In order to avoid having to newly sew the replacement pane into the hood cover or fabric it has already been proposed to cut out the pane to be replaced only to such an extent that a peripheral edge thereof is preserved to which the replacement pane can then be adhered. This operation however can only be carried out once.

The invention is based on the problem of providing a method and a replacement pane suitable therefor with which it is possible to replace a rear pane which has been cut out and which was originally fixedly worked into the hook cover and to enable said replacement pane itself to be replaced again when it has become unusable.

This problem is solved according to the invention by a method according to the characterizing clause of claim 1. Expedient and preferred further developments of the invention are set forth in the subsidiary claims.

Although the invention is described specifically in relation to replacement of rear window panes in convertibles, it can also be applied to all flexible hoods, tops and roofs, for example in tents, as well as to tops of other vehicles, for example trucks and motor boats with fold-down tops.

The invention is based on the idea of inserting a replacement pane in that a releasable adhesive bond is established preferably to the remaining edge region of a cut-out pane. This procedure is preferred because it gives the least application and the easiest to seal installation. However, where the constructional conditions permit it is also possible after cutting out the entire pane to be replaced to stick the replacement pane to the peripheral edge of the hood encircling the window opening.

The releasable adhesion is achieved with a suitable hot-melt adhesive. To soften the adhesive, to establish the adhesive bond and to release it again, in the peripheral edge region of the replacement pane means are provided for heating said edge region and thus the hot-melt adhesive. Said means consist expediently of electrical heating resistance conductors which are worked for example into the peripheral edge of the replacement pane, for example can be cast therein or applied to the surface thereof. At the intended inner side of the pane terminals for the heating conductors are provided via which an external current source can be connected to the pane to activate the heating means.

In a preferred embodiment of the invention the replacement pane itself is not provided with the hot-melt adhesive but instead a specific encircling frame extending along the peripheral edge of the replacement pane. Said encircling frame preferably consists of a flexible expediently textile material and is configured so that on the one hand it overlaps the edge region of the actual replacement pane and also projects freely beyond the edge region of the replacement pane. The encircling frame may be sewn to the replacement pane or alternatively welded or adhered. For safety and sealing reasons two of these types of connections can be simultaneously employed. Preferably, the encircling frame is attached to the intended outer side of the replacement pane so that it overlaps the remaining peripheral region of the old pane and is adhered to the latter so that the new pane and the remainder of the old pane lie in the same plane. The encircling frame expediently extends over the entire remaining region of the old pane, covering the latter from the outside and simultaneously concealing the joint. The encircling frame is preferably made of a textile material, for example black, of low UV-radiation permeability so that the adhesive disposed beneath the encircling frame is not impaired by the action of sunlight over longer periods of time.

If desirable the encircling frame itself may consist of two parts which are separable from each other and can be connected together for example by means of a zip fastener. Such a zip fastener connection must be provided with corresponding sealing means.

The replacement of the pane according to the method of the invention is extremely simple. In the first replacement the old pane is expediently cut out in such a manner that an outer edge region remains. The replacement pane is then placed with its peripheral edge region on the remaining edge region and by corresponding current connection the heating means in the peripheral edge region of the replacement pane are activated, the hot-melt adhesive thereby being softened to enter an adhesive bond with the edge region of the old pane. The current flow is then interrupted and the adhesive can cool, thereby giving a permanently firm bond between the relevant areas. If the first replacement pane in turn becomes unusable the hot-melt adhesive need only be softened again by reapplying a current and in this state the pane which has become useless can be removed and replaced by a new pane of the same type.

Hereinafter the invention will be further explained with the aid of the attached drawings, wherein:

FIG. 1 is a schematic section through a bond according to a first variant of the method and

FIG. 2 is a schematic section through a bond according to a second variant of the method.

In FIG. 1, 1 denotes the cover material of a flexible hood. The remainder 2 of the window pane to be replaced can be seen and is covered in its edge region on the inside by a cover 3. This laminate arrangement is preferably sewn by means of seams 4. The old pane 2 is cut out of the window opening in such a manner that an edge region 5 is left. A flexible replacement pane 6 is provided in its edge region with an encircling frame 7 which is sewn by means of a seam 8 to the pane 6. In addition, the textile encircling frame 7 may be welded by high-frequency welding to the replacement pane 6. In its projecting region the encircling frame 7 is provided at its lower side with a hot-melt adhesive 9. In the encircling frame 7 resistance heating wires 10 are further arranged and when they are subjected to current the hot-melt adhesive 9 can be brought into a softened state. In said state the new pane 6 is placed with its peripheral frame 7 onto the edge region 5 of the old pane and the adhesive then allowed to cool. This gives a permanent and sealing bonding between the edge 5 of the old pane and the new pane 6 or the encircling frame 7 thereof. As is apparent from FIG. 1 the encircling frame 7 covers the connection area completely so that the hood has a pleasant external appearance even with the replacement pane. The electrical terminals, not shown, for the resistance heating wires 10 are provided at the inner side of the pane so that they cannot be tampered with from the outside.

The embodiment of FIG. 2 differs from that of FIG. 1 only is that in this case no remainder of the old pane 2 has been left, The encircling frame 7 being instead adhered directly to the peripheral edge of the hood cover 1. The procedure is the same. As apparent from the illustrations in the drawings the embodiment of FIG. 1 is the more elegant involving less application. However, it has the disadvantage that the pane area of the replacement pane must be somewhat smaller than in the case of FIG. 2.

By resoftening the hot-melt adhesive 9 by activating the resistance heating wires 10 the adhesive bond can be released again when the replacement pane has become unusable and itself is to be replaced by a new one.