Motor car insulating glazing with an augmented exchange surface of the humidity absorbing cord.

The invention relates to a vehicle glazing and more particularly to a sliding door glazing vertically in the form of an insulating glass thin wherein two glass sheets are connected by a spacer frame made of a plastic cord with an absorbent material moisture.

It is known to use as insulating glass panes of vehicles. The insulating glass units provided in this case generally consist of two sheets of relatively thin glass with a thickness of 2 to 3 mm so that the weight of the insulating glazing is limited. Furthermore, it is desired for reasons of "design" of the vehicle body, or the bay window, keep the air layer as thin as possible between the glass sheets. It is for these reasons that the air knife itself has a thickness which is only 2 to 4 mm. This causes the spacer frame also has a section of this thickness. Under these conditions, it is not possible to use a spacer frame made of a hollow metal profile within which to introduce the moisture absorbent material, as is usual with the insulating glazings have a thicker layer of air. That is why in the insulating glass with a very thin layer of air, is used as the spacer frame along the periphery of a plastic cord which comprises the moisture-absorbing material.

Insulating glass for vehicles are known for example by filing DE 35 17 581 A1. The use of a plastic cord which incorporates the moisture absorbent material and which forms part of insulating glazing in tercalaire is described in detail in patents FR 2,294,313 and FR 2,294,314.

The concentration of the moisture absorbent material in the plastic cord can not be increased indefinitely. Indeed, plastic cord must be able to exercise its bonding function, to connect the two sheets of glass and seal to prevent the ingress of moisture or decrease its diffusion through the seal. But as in the case of very thin insulating glass section frame made of plastic cord is very small, the overall amount of the desiccant remains low. There is then a danger that the life of such insulating glass limited since the desiccant material available is also limited. This danger is particularly important in the case of automobile windows because they are subjected to varying external pressure which favors phenomena of diffusion through the intermediate and glues.

The invention aims to improve the insulating glazing to the vehicle such that the danger of the saturated desiccant material decreases and thus the life of the insulating glass is extended.

According to the invention this task is fulfilled by placing on a portion of the periphery of the pane, especially along its lower edge concealed within the door, a plastics cord comprising a moisture absorbent material and having an increased section and a form such that the surface of this plastic bead directed towards the air gap is at least twice the surface area calculated from the thickness and the length of said cord on the side of the air knife.

Appropriate achievements and other developments of the invention arise from the dependent claims and the description of the different following examples illustrated with drawings.

The drawings show successively:<ul><li><b>. figure 1 :</b> a vertical section in a sliding side window vertically</li><li><b>. Figure 2:</b> a first embodiment of the insulating glazing in the lower part shown in perspective, cut and enlarged,</li><li><b>. Figure 3:</b> a second embodiment of the insulating glazing in the lower part in a cross-cut and enlarged perspective.</li></ul>

The insulating glazing 1 is shown as a lateral sliding vertically in a vehicle door glazing 2. The vehicle door 2 includes the door body 3 encompassing the vacuum door 4 and, above this door body coaching window 5. the seal 6 placed along the window frame 5 isolates it from the body. The joints 7 and 8 placed in the door body 3 are the sealing of the door 4 of vacuum based on the door glazing 1 and the gasket 9 placed in the window frame 5 separates it from the glazing 1 insulation.

The insulating glazing unit 1 is constituted of two glass sheets 11 and 12 which delimit the blade 13. The sheets 11 and 12 have a thickness of about 3 mm and are made ​​of glass sé hardened rity. The air space 13 also has a thickness of about 3 mm. Connecting the two glass sheets 11 and 12 at their periphery is carried out by a dual system of a hand using a plastic bead 15 acting as a spacer frame with a thickness of about 3 mm, and on the other hand, outside of this bead 15 a sealing compound 16. the plastic bead 15 is formed for example of butyl rubber having about 20% was mixed by weight of molecular sieve as a drying agent. The sealing mass 16 is advantageously formed of polysulphide.

In the embodiment shown, the inner sheet 11 of insulating glazing 1 is larger than the outer sheet 12. Thus, a shifted insulating glazing. This embodiment provides an aerodynamic vehicle window.

The lower edge 18 of the sheet 11 was mounted preferably by gluing, a metal profile 19 on the wing 20 of the metal profile 19, it will set the operating mechanism for raising or lowering the insulation glazing.

An embodiment of the insulator 1 in its lower part glazing is shown in figure 2. The two glass sheets 22 and 23 having a thickness of about 3 mm which constitute the insulating glazing are separated by an air gap 13. they are equipped at their periphery to the outside of a layer 24, in form of a frame opaque to light. This layer is intended to protect the plastic bead 15 and the sealing 16 against the visible and ultraviolet radiation. This layer 24 is made preferably of a hot paint. In the cord 15 has been introduced with a greater or lesser spacing of the cores 25 made of an incompressible material. These cores 25, which may for example be made of 3 mm diameter beads, have the function when pressing the insulating glass after removing the plastic bead 15 on one of two glass sheets, to avoid crushing irregular cord over the entire periphery. Finally, it was placed next to the plastic bead 15 on the sheet 22, a strip 26 of approximately 10 mm wide and a thickness of 2 mm. This strip 26 is also made of a butyl rubber which was mixed a desiccant. It may be of the same material as that which constitutes the plastic bead 15, but it is also possible to use for this purpose a plastic composition into which has been introduced over desiccant in the cord 15. Since the strip 26 is thinner than the air layer 13 exists between the band 26 and the sheet 23 a slot 27 so that the strip 26 has an absorbent surface area increased humidity.

Figure 3 also has been shown an embodiment wherein the two glass sheets 30 and 31 of insulating glass 1 are equipped on their periphery with a layer 26 in frame form consisting of a hot enamel. Here, the plastic bead 32 which contains the desiccant is a serrated profile in which the teeth 33 are oriented toward the air gap 13. The height of the teeth 33 is of the order of 10 mm. Here we have also introduced into the serrated profile 32 of 25 balls consist of a compressible material, they guarantee a constant gap between the two individual sheets. In addition to the serrated profile 32, here also provided a sealing compound 16, for example polysulphide.

The serrated profile 32 may comprise a preformed profile, and in this case, the land on one of the two glass sheets. But can be advantageously simply remove the plastic cord on one of the sheets using an extrusion head that rests on the glass at the periphery, a cord meandering 34. There is thus obtained the configuration shown in the figure or an adjacent configuration.