It is known in motor vehicles to provide one or more seals, made of polymeric material, often formed integral with an edge trim, and by an extrusion process, for location between an opening in the body of the vehicle i. e. an opening for a door, or the boot or engine compartment, and a closure for the opening, to prevent ingress of air, dirt and moisture. Such seals can be fitted either to the body around the opening therein, or to the door or the like itself. The seals may be of hollow bulbous construction or of flap type construction, and may be secured to the door or body by means of a C-channel, or by a generally U-shaped edge trim which grips a flange, or by fixing clips or studs, or in other ways. It is also known to make the hollow bulbous seals such that they comprise two separate hollow compartments.

The present invention seeks to provide an improved seal of the above described type which incorporates noise reduction features, i. e. which reduces wind and other noise within a vehicle to which it is fitted. The invention also seeks to provide a stiffening carrier suitable for use within such a seal, but which could be used for other purposes.

According to the present invention, we provide a seal for a motor vehicle, the seal being extruded from a polymeric material and comprising a retention part for securing the seal to a vehicle part and a sealing portion for forming a seal with a further vehicle part, a flexible stiffening carrier formed of a different material from, and located at least partly within, the sealing portion, to control the collapse characteristics of the sealing portion when in use and wherein the sealing portion is constructed so that it will form the seal with the further vehicle part at two spaced locations, whereby a sound insulation medium is trapped in the space defined by that portion of the further vehicle part between said two spaced locations and the sealing portion of the seal.

Preferably, the sealing portion is a hollow or bulbous, having two hollows therein separated by a polymeric portion in at least part of which at least part of the stiffening carrier is located.

Alternatively, the sealing portion may comprise two spaced sealing ribs, each incorporating at least part of the stiffening carrier therein.

Preferably, the stiffening carrier is formed of a material, e. g. metal, which is more rigid than the polymeric material and which has at least one limb extending into the sealing portion.

In the preferred construction, the carrier is of generally inverted T-shape in cross- section, with the stem of the"T"extending into the polymeric portion.

Preferably, the sealing portion has sealing surfaces defined by two sealing peaks separated by a valley. In the preferred construction, the valley is aligned with the polymeric portion, but in the alternative construction, the valley is located between the two ribs.

Also according to the present invention, we provide a carrier suitable for stiffening a vehicle seal, the carrier being formed of a relatively stiff but resiliently deformable material so that it can flex to a limited degree throughout its length and having at least two limbs or arms inclined to one another, wherein one of said limbs has a free end region which is resiliently deformable in at least one plane.

Also according to the present invention, we provide a carrier suitable for stiffening a vehicle seal, the carrier being formed of a relatively stiff but resiliently deformable material, and having first and second limbs, wherein the first limb forms a snap fit with the second limb. The snap fit may be such that, when the two limbs are attached to one another, they are hingedly connected.

Also according to the present invention, we provide a carrier having a base portion and two arms upstanding from the base at locations spaced inwardly from end regions of the base portion.

Also according to the present invention, we provide a carrier having a base portion, and upstanding from a central region thereof a stiffening arm.

The end region may be able to swing relative to the remainder of the arm or limb, and is resiliently deformable in its own plane so that the length of the limb is variable.

The carrier may be of generally inverted T-shape in cross-section, with a cross member of the T being adapted for location in a retention part of a seal and the upstanding stem of the T being adapted for location in a sealing portion of the seal.

Alternatively, the carrier may comprise a base portion having two upstanding portions extending therefrom for location within the sealing ribs of the seal.

The carrier may be formed of metal, or be extruded from one or more polymeric materials. If two materials are used, one may be more flexible than the other.

The carrier may be formed of two or more parts which form a snap-fit with one another.

The snap fit joint may be such as to allow limited articulation of one part relative to the other.

One end region of one part may be of sinuous construction to provide control and/or flexibility in at least two planes at right angles to one another.

The cross member of the T may be flat, V-shaped or of inverted V-shape, or of generally hump backed cross section, with the upstanding stem, arm or limb or upstanding portions extending therefrom.

At least one of the limbs, arms or upstanding portions of the carrier may be of a different thickness or material or hardness from the remainder thereof and/or may incorporate a hinge or line of weakness therein.

One or more of the limbs, arms or portions of the carrier may have slots, slits or cut-outs therein.

If the carrier is formed of polymeric material, more than one material, or different hardnesses of material, may be used. Suitable materials might be polypropylene, polyethylene or an elastomer, such as SANTOPRENE (R. T. M.) It should be appreciated that different ones of the above properties of the carrier could be combined, or used in other described embodiments of carrier.

It should also be appreciated that the carrier could be used not only in motor vehicle seals, but as a stiffener in other products, e. g. or for other uses.

Several embodiments of seal for use in motor vehicles and of stiffening carrier for use in such seals or for other uses, are now described by way of example with reference to the accompanying drawings in which:- Figure 1 is a side elevation of part of a motor vehicle showing the two door openings; Figure 2 is a partly schematic section through the A-pillar and doorframe at the point 1 in Figure 1 showing a traditional sealing system; Figure 3 is a view similar to Figure 2, but to an enlarged scale showing a preferred embodiment of seal in accordance with the present invention, but showing the seal in a position of rest and the door partly open; Figure 4 is a view similar to Figure 3, but showing the seal in a sealing or position of use and the door closed;

Figure 5 is a perspective view of part of a stiffening carrier for use in the seal of Figures 3 and 4; Figure 6 is an end view showing part of an alternative construction of carrier; Figure 7 is a view similar to Figure 5 of an alternative design of carrier; Figures 8a, 8b and 8c are schematic end views showing alternative constructions of carrier; Figure 9 is a perspective view of part of a preferred design of the alternative construction of stiffening carrier shown in Figure 8c; Figure 10 is a section through an alternative embodiment of seal according to the invention and incorporating the carrier of Figure 9; and Figures 11 and 12 show views, similar to Figure 10, of alternative embodiments of seal according to the invention.

Referring to Figure 2 of the drawings, a motor vehicle door pillar is shown at 3 and a doorframe at 5. Located on a flange 7 on the door pillar 3 is an edge trim 9 having an integral trim seal 11 and mounted on the frame 5 of the door is a main seal 13 and a sub-seal 15, each seal being located in known manner in a C-channel provided for the purpose in the door frame 5. In this known seal system, three seals are provided by the trim seal 11, the main seal 13 and the sub-seal 15. This is expensive and the pressence of three seals can result in unacceptably high door shut pressures.

In the present invention, the three seals 11,13 and 15 are replaced by a single main seal 17, such as that shown in Figure 3. While the edge trim 9 is still necessary, its trim seal 11 can be omitted and the sub-seal 11 can be omitted altogether. The main seal 17 is extruded from a polymeric material 19 and incorporates therein a stiffening carrier 21.

This carrier 21 is preferably of the construction shown in Figure 5, but could be of other

constructions. The carrier is of generally inverted T-shape with a cross member 23 of the T located in a retention part 25 of the seal and a stem part 27 being located in a central polymeric portion 29 of the seal. The retention part of the seal is located in a C- shaped channel 31 of the door frame 5 and a sealing portion 33 of the seal is of generally bulbous construction, but having two hollows 35 and 37 extending throughout the length thereof, the two hollows being separated by the central polymeric portion 29.

The carrier 21 is preferably formed of metal, and must be formed of a different, preferably stiffer, material than the polymeric material 19.

In the prior art seal shown in Figure 2, a bulbous sealing portion of the seal 13 disclosed therein has a convex sealing surface 14, whereas the embodiment of seal of the present invention shown in Figure 3 has two spaced convex sealing surfaces 39 and 41 separated by a trough 43. In other words, the sealing surface of the sealing portion is defined by two sealing peaks (39,41) separated by a valley 43. As can be seen from Figure 4, when the door of the motor vehicle is swung to a closed position, as illustrated in Figure 4, each of the peaks 39 and 41 and the valley 43 will deform inwardly, thus causing the stem 27 of the carrier 23 to be deformed. As is apparent from Figure 4, the stem 27 of the carrier 21 controls the deformation of the sealing portion 33 in such a way that the peak 39 forms a first seal with the door frame 3, whereas the peak 41 forms a second seal with the door frame 3, leaving an air cavity 45 between the two seal contact areas. This air cavity acts as a cushion to cut down on the passage of sound to the interior of the vehicle, i. e. as a sound insulation barrier. Furthermore, because two spaced seals are formed between the door and the doorframe, a single seal can be used, rather than three separate seals, thus keeping door shut pressures to an acceptable level.

The construction of carrier shown in Figure 5 is one of many possible constructions. In Figure 5, a one-piece carrier is formed of resiliently deformable metal and each of the limbs of the carrier has a plurality of slots or slits 47 stamped therein. This allows the carrier to be bent in various planes so that when it is located within an extruded seal such as the seal of the present invention, the seal can be fitted around the periphery of the door of the motor vehicle. Due to the resilient nature of the limbs of the carrier, the carrier can deform from the position shown in Figure 3 to its Figure 4 position.

In the alternative construction of carrier shown in Figure 6, the carrier can not only deform as shown in Figure 4, but also in the plane of one of the limbs thereof so as to allow the limb not only to pivot relative to the other limbs, but also to be shortened.

The carrier differs from that shown in Figure 5 in that the end region of a stem portion 27a of the carrier is of sinuous construction as shown at 49. This sinuous construction 49 allows the stem 27a to swing in the direction of the arrows 51 or to act in a spring- line like matter, i. e. to contract and/or extend in the direction of the arrows 53. These features are particularly useful for controlling the amount of collapse of the polymeric portion 29 of the carrier shown in Figure 3.

The carrier shown in Figure 7 has a cross member 55 with a central hinge groove 57 therein within which a bulbous end portion 59 of a stem portion 61 engages with a snap fit. Movement restriction means 63 is also provided either on the stem portion 61 or upstanding from the cross member 55, which controls the amount by which the stem portion 61 can swing to and fro, as represented by the arrows 51, relative to the cross member 55. A line of weakness 65 or other means such as a sinuous formation is formed in the stem portion 61 at a central region thereof to allow the end region of the stem portion to swing relative to the lower end thereof.

Alternative constructions of carrier are illustrated in Figures 8a, 8b and 8c in which the cross member thereof is shown of generally inverted V-shape 69 in Figure 8a, or of generally V-shaped construction 71, as shown in Figure 8b. In other respects, the carrier could incorporate the features shown in any one or more of the constructions shown in Figures 5 to 7.

In the carrier shown in Figure 8c, the inverted V-shaped portion 69 is replaced by a hump backed cross member 81, which is shown in greater detail in Figure 9.

As can be seen from Figure 9, the carrier has a plurality of slits or slots 47 in its upstanding stem 83, and a plurality of wider slots 85 in each limb of its cross member 81. The stem 83 extends from the upper region 87 of the cross member 81.

Figure 10 shows an alternative embodiment of seal 91 which has the carrier of Figure 9 incorporated therein. The seal has two ear like sealing portions 93 of hollow construction sharing a central polymeric portion 93 into which the stem 83 of the carrier extends to control the collapse of the sealing portions 93. The hump backed cross member 81 is mainly located in a retention part 97 of the seal, which is secured to the body of the motor vehicle in generally known manner using a plurality of retaining studs 99.

The alternative embodiment of seal 110 shown in Figure 11 has two upstanding, diverging sealing ribs 101 and a retention part 103, with a yet further design of stiffening carrier 105 located therein. The carrier 105 has a base portion 107 located wholly within the retention part 105 and two diverging stiffening fins 107 located in respective ones of the sealing ribs 101 to control the collapse characteristics thereof.

The alternative embodiment of seal 110 shown in Figure 12 is generally similar to that of Figure 11, but incorporates a stiffening carrier 111 therein which has two stiffening fins 117 upstanding from a hump backed cross member 113 similar to cross member 81.

The seal has some similarities to the seals shown in Figures 10 and 11, and like parts have the same reference numerals. The scrap view 115 in Figure 12 shows a modified sealing rib 102 incorporating a stiffening fin 104 with a sinuous end portion 106 similar to sinuous construction 49 shown in Figure 6.

Instead of being formed of metal, the carriers could be extruded from one or more polymeric materials, e. g. thermosetting or thermoplastic, and/or of different flexibility or hardness: furthermore the stiffness of the carrier could be influenced by its thickness as well as by the material/shape/constructional/density characteristics.

It should be appreciated that various features of respective ones of the carriers described herein could be incorporated into various other carriers described herein, and that any of these carriers, where suitable, could be used in various embodiments of seal illustrated in the accompanying drawings and described herein, in place of the carriers illustrated in the respective drawings.

The above-described carriers can be used for purposes other than stiffening the seal shown in Figures 3 and 4 herein.

It will, of course, be understood that the present invention has been described above purely by way of example, and modifications of detail can be made within the scope of the invention.