GB2092244A

GB2092244A - Flat gasket

Info

Publication number: GB2092244A
Application number: GB8202344A
Authority: GB
Original assignee: LECHLER ELRING DICHTUNGSWERKE; Elring Dichtungswerke GmbH
Current assignee: LECHLER ELRING DICHTUNGSWERKE; Elring Dichtungswerke GmbH
Priority date: 1981-02-03
Filing date: 1982-01-27
Publication date: 1982-08-11
Also published as: FR2499197A1

Abstract

A flat gasket of resilient material (10) for a cylinder-head includes apertures (12, 15), the edges of which are provided with continuous edging or seating members (17, 26). The members (17, 26) are connected to the resilient material (10) by a plurality of angled tongue-like fastening elements (23-25, 31-32), which embracing engage the adjacent soft material (10). <IMAGE>

Description

SPECIFICATION Flat gasket This invention relates to a flat gasket, for an internal combustion engine cylinder head or the like, of the type consisting of a resilient material, possibly reinforced with metal, and having apertures. The edges of the apertures are provided with continuous edging or seating members for the parts which are to be sealed off relative to one another, these edgings or seats being connected to the resilient material by means of metal elements which embracingly engage the adjacent resilient material.

A cylinder-head gasket of the kind described hereinbefore is known, for example, from German Gebrauchsmuster 7710555. As is generally conventional in cylinder-head gaskets of this kind, the known gasket comprises, on each of its combustion chamber passages, an edge binding which is U-shaped in cross section and engages with its two flank portions on both sides of adjacent resilient or soft material of the gasket and in this way is connected to the soft material.

An object of the present invention is to generally reduce the material and assembly costs for flat gaskets of this kind. This is intended to reduce the overall manufacturing costs for such gaskets.

According to the invention there is provided a flat gasket of resilient material for an internal combustion engine cylinder-head or the like, said gasket having at least one aperture which is provided with either a continuous edging or seating member adjacent its periphery, the member being secured to the resilient gasket material by means of a plurality of metal angled tongue-like fastening elements which embracingly engage the upper and/or lower surfaces of the gasket material.

An advantage obtained with the invention is that for example in the case of a metal edging member only one flank of the combustion chamber edging needs to be widened to engage one surface of the resilient gasket material and there is no longer any need for the other flank of the combustion chamber edging to engage over the resilient material on the opposite surface.

In an appropriate embodiment of the invention, it is proposed that individual tongue-like fastening elements are bent out of a flank portion of the metal edging member and engage the soft material on one side, these fastening elements being bent first in the axial direction or substantially in the axial direction and then in the radial direction relative to the aperture.

The invention is particularly suitable for use in cylinder-head gaskets wherein preferably metallic additional gasket material is surrounded by the metal edge member which is substantially Ushaped in cross section and is completely or largely separated from the adjacent resilient or soft material by an annular gap. The annular gap may have the tongue-like fastening elements passing axially or substantially axially therethrough, the advantage of this being that no special recesses need be provided in the soft material for the insertion of the tongue-like fastening elements.

As a further advantageous feature of the invention, it is proposed that the metal edge member of U-shaped cross section engages over one side of the adjacent soft material over all or most of the periphery of the aperture, and that individual tongue-like fastening elements be bent so as to engage the opposite side of the adjacent soft material. The individual tongue-like fastening elements have a small surface area. Consequently, small assembly forces are sufficient to press them far enough into the soft material to prevent undesirable bracing, which would reduce the sealing compression.

However, in order to achieve a substantial saving in materials, this advantageous embodiment can be further improved if the metal edging member which is U-shaped in cross section engages over one side of the adjacent soft material only at individual points, preferably three points on the periphery of the aperture, and if individual tongue-like fastening elements are bent so as to engage the opposite surface of the adjacent soft material.

The offset arrangement of the sealing elements according to the preferred embodiment has the following advantages: a) there is no need for any pulling of flank portions of edgings of greatly varying widths.

b) The width of the flanks of the edgings may be selected only to suit the conditions of sealing compression, and not the method of fastening.

This means that the functional design does not compete with the equally important assembly-oriented design of the gasket.

c) Detrimental accumulations of material are avoided. Consequently, the sealing compression and the distribution of pressure in the gasket are evened out.

A preferred embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which: Fig. 1 shows an embodiment of a cylinder-head gasket for internal combustion engines, in plan view (partial representation), Fig. 2 shows a section on the line Il-Il in Fig.

1, Fig. 3 shows a section on the line Ill-Ill in Fig.

1, Fig. 4 shows another embodiment of a cylinderhead gasket, viewed as in Fig. 1, Fig. 5 is a section on the line V-V in Fig. 4, Fig. 6 is a section on the line VI---VI in Fig. 4, Fig. 7 is a section on the line VIl-VIl in Fig. 4, Fig. 8 is a section on the line VIll-VIll in Fig. 7, Fig. 9 is a component of a cylinder-head gasket, in the form of a pre-assembled part, viewed in section according to Fig. 2, and Fig. 10 is another component of a cylinderhead gasket, again in the form of a pre-assembled part, viewed in section according to Fig. 3.

The cylinder-head gasket shown in Figs. 1 to 3 consists essentially of a soft material 10 in the form of a plate or sheet, in which metal reinforcements 11 are embedded. Numerous apertures or recesses, e.g. 12 to 16, are stamped out from the soft material 10 in the usual way and serve, in known manner, as passages for fixing screws, coolants, lubricants and the like. The large-diameter circular recesses numbered 12 are the combustion chamber passages. The combustion chamber passages 12 are surrounded by a metal edging member or binding 1 7 of U shaped cross section, by means of which the soft gasket material immediately adjacent to the combustion chamber is protected from the high thermal and mechanical stress encountered there.

The structure of the combustion chamber binding 1 7 is shown in detail in the enlarged view in Fig. 2.

According to this figure, the combustion chamber binding 17 comprises two flanks 18, 19 between which a two-ply annular insert 20, 21 of metallic gasket material is enclosed. An annular gap 22 with a width b extends between the metal insert 20, 21 and the adjacent soft material 10.

As shown in Fig. 1, the lower flank 1 8 of the combustion chamber binding 17 has three tongue-like extensions 23, 24 and 25 at each of a total of three points on its circumference. The two outer tongue-like fastening elements 23, 24, shown by broken lines in Fig. 1, engage underneath the soft material 10 on the underside thereof, whereas - as shown in Fig. 2 - the central tongue-iike fastening element 25 is bent upwards and finally engages over the upper surface of the soft material 1 0. The central tongue-like fastening element 25 passes through the annular gap 22 referred to hereinbefore, which advantageously also serves as a recess for the passage of the tongue-like fastening element 25.

The recess 22 in the form of an annular gap also serves to prevent rotation of the combustion chamber binding 1 7 and as an adjustment aid for the assembly thereof.

Figure 3 shows an enlarged section through two other passages in the cylinder-head gasket, which are designated 1 5 and 15a, respectively, in Fig. 1. The passages 1 5 and 1 5a are surrounded by annular seating members in the form of rubber supports 26 and 26a, respectively each of which has a corrugated surface 27 and 28 on each side.

The rubber support 26, 26a has a radial slot 29 in which a sheet metal element 30 engages. The sheet metal element 30 is cut away radially in its rear portion to form two tongue-like fastening elements 31, 32 (or 31 a, 32a, respectively) which are bent upwardly and engage over the top of the soft material 10 (Fig. 3). The lower flank 33 of the sheet metal element 30, this flank extending continuously over the entire circumference of the recess 1 5 or 15a, also has a bent portion, albeit in this case bent downwards, so that it engages over the underside of the soft material 10 (Fig. 3). Thus, the rubber support 26, 26a as a whole, i.e. viewed in cross section, is symmetrical.The rubber support 26, 26a itself, i.e. without the metal retaining element 70, may be produced as a stamped part or by the metre, and secured by adhesive bonding, in the case of small production runs, or be sprayed on, in the case of mass production.

An embodiment of a cylinder-head gasket as shown in Figs. 4 to 8 will now be described. The fundamental construction, i.e. the basic soft material 10 with metal reinforcements 11, corresponds to that of the embodiment shown in Figures 1 to 3. Here, too, the combustion chamber passage designated 12, as in the embodiment according to Figs. 1 to 3, has a combustion chamber binding 1 7 of sheet metal material, U-shaped in cross section, which encloses a metal insert 20b between its two flanks 1 8b and 19b.

The essential difference between this embodiment and the embodiment of Figs. 1 to 3 is that the upper flank 1 9b of the combustion chamber binding 1 7b abuts, over a substantial part of its entire periphery, on the soft material 10 (cf. particularly Figs. 4 and 5). The lower flank 18b, on the other hand, is provided with extended portions only at a total of four points on its circumference and at these points it engages with tongue-like fastening elements 25b underneath the soft material, on the underside thereof (Fig. 7).

Another special feature of the embodiment according to Figs. 7 and 8 is that the flank 1 9b of the metal edge binding 17b, which engages over the soft material on one side and forms the retaining plane, is corrugated in the region of the recess 22 in the form of an annular gap. A plurality of corrugations 33, which are radially directed, relative to the associated passage 12b, are provided, which are arranged in a star shape at regular intervals in the circumferentiai direction.

The corrugations 33 advantageously serve to reinforce the gasket and improve the centering thereof.

Fig. 9 illustrates the assembly of the combustion chamber binding 1 7, e.g. of the kind shown in Figs. 1 and 2. The combustion chamber binding 1 7 is constructed as a pre-assembled part (already calibrated, with inserted parts 20 centered), whilst the tongue-like fastening element 25 is first bent only in the axial direction, as shown by continuous lines in Fig. 9, i.e. bent upwards, in the view according to Fig. 9. The two lateral tongue-like fastening elements 23 and 24 (cf. Figs. 1 and 2), on the other hand, are already in their final position (radial direction) in the preassembled state of the part 1 7. The part 1 7 can now be inserted in the combustion chamber recess 12 in the soft material; then the tongue-like fastening element 25 is bent round in the radial direction and pressed into the soft material 10 by the application of suitable pressing forces (shown by broken lines). The pressing forces required are only slight, owing to the relatively small surface areas of the fastening elements 23 to 25.

Fig. 10 shows a possible assembly for the rubber support 26 according to Fig. 3. The parts 26, 30 form a pre-assembled unit, and in the preassembled state, the tongue-like fastening element 32, as in the embodiment shown in Fig.

9, is bent perpendicularly upwards, and it is not until the unit 26, 30 is assembled with the soft material 10 that this fastening element 32 is bent round in the radial direction and pressed into the soft material 1 0.

Claims

1. A flat gasket of resilient material for an internal combustion engine cylinder-head or the like, said gasket having at least one aperture which is provided with either a continuous edging or seating member adjacent its periphery, the member being secured to the resilient gasket material by means of a plurality of metal angled tongue-like fastening elements which embracingly engage the upper and/or lower surfaces of the gasket material.

2. A flat gasket as claimed in claim 1 having a metal edging member of U-shaped cross-section which includes spaced flank portions wherein the individual tongue-like fastening elements are bent out of one of said flank portions and extend from the flank portion first in an axial direction or a generally axial direction and then in a radial direction relative to the aperture, so as to extend over a surface of the resilient gasket material.

3. A flat gasket as claimed in claim 2 wherein the resilient gasket material is cut away at certain locations to accommodate the tongue-like fastening elements passing axially or generally axially therethrough.

4. A flat gasket as claimed in claim 2 or 3, further comprising additional gasket material of metal or the like surrounded by the metal edging member, the additional gasket material being separated from at least a major part of the adjacent soft material by an annular gap wherein the annular gap has the tongue-like fastening elements passing axially or generally axially therethrough.

5. A flat gasket as claimed in claim 2, 3 or 4, wherein a part of said edging member engages one surface of the adjacent resilient gasket material over at least a major part of the periphery of the aperture, and the individual tongue-like fastening elements are bent out of the plane of said part of the edging member and engage the opposite surface of the adjacent resilient gasket material.

6. A flat gasket as claimed in claims 2, 3 or 4, wherein one surface of the resilient gasket material is engaged by the edging member only at individual locations around the periphery of the aperture, and the individual tongue-liKe fastening elements are bent out of the plane of said one surface of the resilient gasket material and engage the opposite surface of the resilient gasket material.

7. A flat gasket as claimed in claim 6 wherein said one surface of the resilient gasket material is engaged by the edging member at three locations around the outer periphery of the aperture.

8. A flat gasket as claimed in claim 6 or 7 wherein the edging member of U-shaped crosssection engages one surface of the adjacent resilient gasket material by means of two tonguelike fastening elements and a third, angled, tongue-like fastening element which engages the opposite surface of the adjacent resilient gasket material is bent out of the plane of, and lies between, said two tongue-like fastening elements.

9. A flat gasket as claimed in claim 1, having a seating member of rubber or a like material and adapted to follow the contours of the aperture wherein a metal element which mounts the seating member has a central portion which engages a slot-shaped recess in the seating member, and the metal element is bent so as to engage the adjacent resilient gasket material on both surfaces.

10. A flat gasket as claimed in claim 9, wherein a part of the metal element engages one surface of the adjacent resilient gasket material over at least a major part of the periphery of the aperture and the individual tongue-like fastening elements are bent so as to engage the opposite surface of the adjacent resilient gasket material.

11. A flat gasket as claimed in any of claims 2 to 10 wherein the metallic edging member or metal element is in the form of a stamped part and, in the pre-assembled state, the tongue-like fastening elements extend normally from the plane of the flank portions, or central portion respectively.

12. A flat gasket as claimed in claims 4 and 11 wherein the metal edging member including the additional gasket material is formed as a preassembled part and is connected to the resilient gasket material by means of the tongue-like fastening elements.

13. A flat gasket as claimed in one or more of claims 2 to 8 wherein a flank portion of the metal edging member engages one surface of the resilient gasket material and is provided with corrugations which define an annular gap between the edging member and the resilient gasket material.

14. A flat gasket as claimed in claim 12, wherein the corrugations are radially directed relative to the aperture, and are arranged at regular intervals around the circumference of the aperture.

1 5. A flat gasket substantially as hereindescribed with reference to any of the accompanying drawings.