GB1574755A - Joint incorporating a gasket - Google Patents

Description

(54) JOINT INCORPORATING A GASKET (71) We, KLÖCKNER- HUMBOLDT-DEUTZ AKTIENGESELLSCHAFT, a German Body Corporate, of Köln-Deutz, German Federal Republic, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a gasket, for example a gasket for sealing portions of a water-cooled exhaust manifold. and also to a joint incorporating such gasket.

Water-cooled exhaust manifolds in highpower internal-combustion engines comprise one or more exhaust-gas conveying ducts surrounded by a cooling-water jacket.

Usually, the manifold is made up of a number of portions, one portion being provided, if required, for each cylinder unit of the internal-combustion engine. The cooling water flows from the jacket of one portion to the jacket of the next portion via apertures at the flanged end faces, which apertures are disposed radially around the exhaust-gas duct or ducts. It is very difficult to seal the portions to one another. It is widely known to dispose a gasket between the portions of the manifold, the gas and water passages in the gasket being surrounded by annular flanges which are raised relative to the thickness of the gasket. When the gasket is new, it can exert high pressure per unit area on the periphery of the gas or water apertures of the manifold. but after a short time the high temperatures and the temperature fluctuations of more than 600"C in the exhaust manifold during operation result in the permanant deformation of the raised flanges of the gaskets so that leakage may occur.

An aim of the present invention is to provide an improved gasket joint, a preferred embodiment of which is particularly suitable for sealing portions of a water-cooled exhaust manifold.

Accordingly, the invention is directed to a joint comprising two members connected together with a gasket disposed between the members, the gasket comprising a metallic part which has an aperture through it and is made of reinforced with metal, and a resiliently deformable ring made of an elastomeric material and disposed in the aperture in the metallic part so as to engage the wall of the aperture, thr ring when in its undeformed state being of greater thickness than the metallic gasket part (at least in the region of the metallic gasket part which the ring engages) so that the ring extends proud from at least one main face of the metallic part, at least one of the members having a face engaging the metallic gasket part, said face having a recess which receives the part of the said ring which extends proud, such ring part seating on the base of the recess.

In order to locate the ring securely in place in the aperture, the ring may be formed with a rim, lip or flange for engaging a main face of the metallic gasket part around the aperture.

If the gasket is to be used in a water-cooled exhaust manifold, then the ring must be made of a material which is resistant to high temperatures, and one such material is man ufactured by E.I. du Pont de Nemours & Co.

under the Trade Mark "Viton". "Viton" is a synthetic rubber based on a copolymer of vinylidene fluoride and hexafluoropropene.

For use with a said exhaust manifold, the gasket must also have a generally central opening through which, in use of the gasket, exhaust gases will flow. There will also be a number of the said apertures fitted with elastomeric rings, and in use of the gasket, water will flow through the rings.

It will be appreciated that the invention also relates to the gasket itself.

The resilient rings can be O-rings, and they serve to compensate for any deformation occurring between the flanges of the members and thus prevent the liquid medium, i.e.

cooling water, from escaping or overflowing into the gas duct. The forces required to compress the resilient rings are small, and thus do not deform the flanges of the members or affect the distribution of pressure on the metallic gasket part which can therefore be designed in optimum manner for sealing the gas duct.

Two embodiments of a gasket joint according to the invention will now be described by way of example with reference to the accompanying drawing, in which: Figure 1 is a view of a flange of a watercooled exhaust-gas manifold comprising a gas duct having an oval cross-section; Figure 2 is a longitudinal section along the line II-II in Figure 1 through two screwedtogether portions of the exhaust manifold separated by a gasket according to the invention; Figure 3 is a view of a flange of a watercooled exhaust-gas-manifold comprising a gas duct having a circular cross-section; and Figure 4 is a longitudinal section along line IV-IV in Figure 3 through two screwedtogether portions of the exhaust-gas manifold separated by a gasket according to the invention.

The drawing shows a water-cooled exhaust manifold 1 comprising a gas duct 2 having an oval cross-section in Figures 1 and 2 and a circular cross-section in Figures 3 and 4.

Manifold 1 is made up of portions 3 having endfaces in the form of flanges 4 which are secured together. In portions 3, each gas duct 2 is surrounded by a cooling-water jacket 5, and the jackets 5 of the individual portions are interconnected via a number of apertures 6 in the form of bores in flanges 4. A gasket 7 is disposed between the flanges 4. Gasket 7 has a generally central gas flow opening 8 in register with the ducts 2, and water flow apertures 9 in register with the flange apertures 6. Resilient sealing rings 11 made of an elastomeric material such as "Viton" are disposed in each aperture 9.

The rings 11 are of such thickness that they extend proud of one main face of the remainer of the gasket which is metallic, i.e.

made of or reinforced with metal. The part which extends proud may be widened in a region 10 to form a rim. flange or lip for engaging the main face of the metallic gasket part. The flange 4 of one of the members 3 has a face which engages the metallic part of the gasket. said face having recesses 12 which receive part of the rings 11, i.e. the part of the rings which extend proud of the main face of the metallic gasket part.

The water passages between aligned apertures 6 in flanges 4 are sealed by the resilient rings 11, which. being made of "Viton". are resistant to high temperatures. Rings 11 engage the bases ofthe recesses 12 and serve to compensate for deformations of the flanges 4 and efficiently prevent cooling water from escaping or overflowing into duct 2, or exhaust gases from flowing into the cooling-water jacket 5.

WHAT WE CLAIM IS: 1. A joint comprising two members connected together with a gasket disposed between the members, the gasket comprising a metallic part which has an aperture through it and is made of or reinforced with metal, and a resiliently deformable ring made of an elastomeric material and disposed in the aperture in the metallic part so as to engage the wall of the aperture, the ring when in its undeformed state being of greater thickness than the metallic gasket part (at least in the region of the metallic gasket part which the ring engages) so that the ring extends proud from at least one main face of the metallic part, at least one of the members face having a recess which receives the part of the said ring which extends proud, such ring part seating on the base of the recess.

2. A joint according to claim 1, in which the elastomeric ring is formed with a rim, lip or flange for engaging a main face of the metallic gasket part around the aperture.

3. A joint according to claim 1 or claim 2, in which the ring is made of a material resistant to high temperatures.

4. A joint according to claim 3, in which the ring is made of a synthetic rubber based on a co-polymer of vinylidene fluoride and hexafluoropropene.

5. A joint according to any preceding claim, in which the metallic gasket part has a generally central opening, and a plurality of said apertures disposed around the central opening, each aperture having a said elastomeric ring disposed in it. the members each having a central opening in register with the central opening in the gasket, and having flanges formed with aligned apertures in register with the said apertures in the gasket, the rings forming a fluid tight seal between aligned flange apertures, at least one of the flanges of the two members being formed with a plurality of said recesses to receive parts of the said rings.

6. A water cooled exhaust manifold including a joint according to claim 5.

7. A water cooled exhaust manifold having facing flanges connected together with a gasket between them substantially as described herein with reference to the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. cooling water, from escaping or overflowing into the gas duct. The forces required to compress the resilient rings are small, and thus do not deform the flanges of the members or affect the distribution of pressure on the metallic gasket part which can therefore be designed in optimum manner for sealing the gas duct. Two embodiments of a gasket joint according to the invention will now be described by way of example with reference to the accompanying drawing, in which: Figure 1 is a view of a flange of a watercooled exhaust-gas manifold comprising a gas duct having an oval cross-section; Figure 2 is a longitudinal section along the line II-II in Figure 1 through two screwedtogether portions of the exhaust manifold separated by a gasket according to the invention; Figure 3 is a view of a flange of a watercooled exhaust-gas-manifold comprising a gas duct having a circular cross-section; and Figure 4 is a longitudinal section along line IV-IV in Figure 3 through two screwedtogether portions of the exhaust-gas manifold separated by a gasket according to the invention. The drawing shows a water-cooled exhaust manifold 1 comprising a gas duct 2 having an oval cross-section in Figures 1 and 2 and a circular cross-section in Figures 3 and 4. Manifold 1 is made up of portions 3 having endfaces in the form of flanges 4 which are secured together. In portions 3, each gas duct 2 is surrounded by a cooling-water jacket 5, and the jackets 5 of the individual portions are interconnected via a number of apertures 6 in the form of bores in flanges 4. A gasket 7 is disposed between the flanges 4. Gasket 7 has a generally central gas flow opening 8 in register with the ducts 2, and water flow apertures 9 in register with the flange apertures 6. Resilient sealing rings 11 made of an elastomeric material such as "Viton" are disposed in each aperture 9. The rings 11 are of such thickness that they extend proud of one main face of the remainer of the gasket which is metallic, i.e. made of or reinforced with metal. The part which extends proud may be widened in a region 10 to form a rim. flange or lip for engaging the main face of the metallic gasket part. The flange 4 of one of the members 3 has a face which engages the metallic part of the gasket. said face having recesses 12 which receive part of the rings 11, i.e. the part of the rings which extend proud of the main face of the metallic gasket part. The water passages between aligned apertures 6 in flanges 4 are sealed by the resilient rings 11, which. being made of "Viton". are resistant to high temperatures. Rings 11 engage the bases ofthe recesses 12 and serve to compensate for deformations of the flanges 4 and efficiently prevent cooling water from escaping or overflowing into duct 2, or exhaust gases from flowing into the cooling-water jacket 5. WHAT WE CLAIM IS:

1. A joint comprising two members connected together with a gasket disposed between the members, the gasket comprising a metallic part which has an aperture through it and is made of or reinforced with metal, and a resiliently deformable ring made of an elastomeric material and disposed in the aperture in the metallic part so as to engage the wall of the aperture, the ring when in its undeformed state being of greater thickness than the metallic gasket part (at least in the region of the metallic gasket part which the ring engages) so that the ring extends proud from at least one main face of the metallic part, at least one of the members face having a recess which receives the part of the said ring which extends proud, such ring part seating on the base of the recess.

2. A joint according to claim 1, in which the elastomeric ring is formed with a rim, lip or flange for engaging a main face of the metallic gasket part around the aperture.

3. A joint according to claim 1 or claim 2, in which the ring is made of a material resistant to high temperatures.

4. A joint according to claim 3, in which the ring is made of a synthetic rubber based on a co-polymer of vinylidene fluoride and hexafluoropropene.

5. A joint according to any preceding claim, in which the metallic gasket part has a generally central opening, and a plurality of said apertures disposed around the central opening, each aperture having a said elastomeric ring disposed in it. the members each having a central opening in register with the central opening in the gasket, and having flanges formed with aligned apertures in register with the said apertures in the gasket, the rings forming a fluid tight seal between aligned flange apertures, at least one of the flanges of the two members being formed with a plurality of said recesses to receive parts of the said rings.

6. A water cooled exhaust manifold including a joint according to claim 5.

7. A water cooled exhaust manifold having facing flanges connected together with a gasket between them substantially as described herein with reference to the accompanying drawing.