DE2142441A1 - Warm insulating seal - Google Patents

Description

PATENT LAWYERS DIPL-ING. CURT WALLACH DIPL.-ING. GONTHER KOCH 2142441 DReTINO HAIBACH Munich 2, 2k _t Aug. 1971 OUR SIGN: 1Y 352

... JM). PARSTAM CO. Lyons, Illinois, V.St.A.

Heat insulating seal

In modern, sensitive high-performance internal combustion engines, particular difficulties arise with regard to the formation of the mixture. Since most modern motor vehicles have a low overall height, since the space under the bonnet is practically insulated, and since cooling air can only pass over the engine to a limited extent, there is a considerable risk of heat build-up in the carburetor; This is especially true if the engine is switched off after normal use of the car. If the build-up of heat is increased by the transfer of heat from the engine's intake manifold to the carburetor, these difficulties are even greater ₉ and therefore it is © i It is necessary to provide seals ₉ that provide sufficient © thermal insulation between the intake manifold and the throttle body of the carburetor and in some cases between the throttle body and the fuel chamber

- Je & öcla int es sicfet xm &

2U2441

Provide construction which enables a proper seal to be ensured between the flanged components between which such a thermal insulation construction is arranged. If an insulating structure is to be provided between the throttle body and the intake line, care must therefore be taken to ensure that a proper seal is achieved at the interfaces between these components. However, the construction described above must not only provide thermal insulation and a seal, but it is also necessary to design the construction so that the fastening means can be tightened with a large torque so that the parts of the carburetor assembly maintain their tightness even during long periods of operation, or so that the parts can be reassembled properly even if one component had to be separated from the other component in order to enable maintenance work to be carried out. This insulation and sealing structure must also be designed so that it can perform these important tasks without distortion or deformation of the metal components between which the structure is arranged, because these metal parts often consist of soft and pliable Materials such as aluminum or zinc. The term "deformation" here means that when an insulation and sealing structure is used between two facing flanges of components, and when the two components are firmly screwed together with the structure in between, a deflection or bulge or © ine different type of deformation of the components occurs · In many cases, in a construction, _s which is clamped between SWEi components danger "that a so-called spring effect" _occurs% of endeavors $ Verfoxsttrag a one or * fesider Faßfläoaen of each other.

lÖüiÖ / 1S

2U2A41

connected components causes. Such a deformation is of course, very undesirable, because this makes the complete seal between the mating surfaces more or less largely canceled, and bridges may even appear on the throttle body near the screw holes. The invention is now based on the object of avoiding the above-described disadvantages of known seal constructions and to seal constructions create that meet the requirements mentioned.

It has already been proposed to use one or more components in order to achieve thermal insulation, a seal, the correct absorption of torques and a reduction in deformation to a minimum in the very sensitive carburetor assembly of an internal combustion engine. Most of these prior art proposals, however, have found it impossible to meet all of the requirements so that proper insulation and sealing is achieved and that the fasteners do not loosen. When a certain task was solved, new difficulties arose, and it is not possible up to now to influence and adjust the variable quantities, which play a role in the solution of the overall problem, independently of one another. It is now assumed, that the invention provides a heat-insulating and sealing structure that all of the above requirements _corresponds% so that it has proven itself in practice, in use in a carburetor assembly, and that constructions of the invention can be produced in an economical V / ice.

One embodiment of the invention is a connection to a motor vehicle engine using insulation and sealing construction, which at least comprises two components, namely a heat insulation

209810/1669

The first component that causes the induction, and a seal causing second component; in this case, the first component forms edge sections that go through within the assembly Holding means, ζ. B "Screws or the like held v / ground, and their density considerably greater i ^ t than that Density of the remaining sections of the components. More precisely the invention proposes a heat-insulating and a seal effecting sealing construction that a thermally insulating member of selected thickness and shape, generally having a central opening, and with several continuous screwless brazen is provided, the are distributed over its umiang at intervals. At a Embodiment, these screwdrivers are larger than it would be required to receive the screws, and in each screw hole there is an annular insert of high Strength arranged, dss consists of a .verkstoff with low thermal conductivity and has an opening, which forms a screw hole with the correct diameter. At least on one side of the heat-insulating A layer of a sealing material is arranged on the component, which generally has the same shape as said component, and that with the heat-insulating component can be connected by gluing. An endless sealing bead can be attached to part of one of the layers of the seal be trained, the opposite of the »xtand. of construction is offset inward and surrounds the central opening; this seal a / ulst has a considerably lower density than the remaining parts of the sealing layer from which he forms a component, so that the ichtung'swulst very elastic and adaptable so that it becomes a complete Sealing on the (L'rennfuge of the carburetor assembly where the seal is used, Finally the invention proposes special methods for producing the inventive oiling and sealing structures before",

209810/1669

The invention and advantageous details of the invention are described in the following on the basis of schematic drawings explained in more detail using exemplary embodiments.

iig. 1 schematically illustrates how the constructions according to the invention can be used.

Pig. FIG. 2 is an enlarged perspective view of an embodiment of the invention as used in FIG The assembly of Fig. 1 could be used.

Pig. $ is one drawn on an even larger scale Shortened partial section along the line 3-3 in FIG.

Pig. 4-A and 4B show in shortened partial sections further embodiments of the invention.

Pig. Figures 5A and 5B show in a somewhat exaggerated manner Scale and in simplified partial sections a component of the embodiment according to Pig. 3.

Pig. 6 is similar to Pig. 1, but shows a further modified version in a perspective partial representation form of the invention.

Pig. 7 is a partial section taken along line 7-7 in FIG Pig. 6th

Pig. 8 shows a bent apart sectional view the components of the seal according to Pig * 6 and 7 before their union.

Pig. 9 is similar to Pig. 7 », however, shows the seal in their position between two components of an assembly.

Similar components are shown in the drawings the same reference numbers denote b; in Pig. 1 is the

^ '209810/1669

Purpose of the constructions according to the invention shown. According to Fig. 1, a carburetor assembly 2 designed in a known manner with the associated air filter 4-known type is connected by a wing nut to a carburetor upper part 12, which in turn is fastened by means of screws 5 to a throttle valve housing 14, which in turn is fastened by screws 6 to an intake port 8 connected is. Although Fig. 1 shows the parts mentioned in a greatly simplified representation, but it can be clearly seen that the heat-insulating sealing structure 10 according to the invention is arranged between the puddles 3 and 7 of the components 2 and 8 to prevent the remaining parts, not shown of the hotors lead to a build-up of heat in the sensitive mixture formation zone. The use of the construction 10 according to the invention has the effect that a deformation of the discharge surfaces on the flanges 3 and 7, etc., components 2 and δ is essentially prevented, that the applied torques are retained, and that a perfect seal is achieved is of particular importance when one considers that the hydrocarbon fuels normally used in internal combustion engines evaporate even at a low temperature.

FIG. 2 shows a preferred embodiment of one according to the invention heat-insulating sealing construction, those in the assembly according to -Fig. 1 can be used as a seal 10, but it should be noted that such a Arrange the sealing construction between the sensitive throttle valve housing and the upper part 12 of the carburetor could * The total of 16 designated heat-insulating sealing construction has a Aukenform, which is generally used for The size and shape of the flange surfaces fits between which the structure is placed. According to Fig. 2, the construction Approaches distributed at circumferential distances 18 mib

209810/1689

The construction is provided with an endless sealing bead 22, which is described in more detail below _o

The heat insulating Dichtungskonctruktion 16 of FIG. 2 unifaiit an inner core or _o a laminate 24 ₉ which is composed in the present Pail of two! Layers 24a and 24b which are joined together by an adhesive layer 26 "The laminate 24 could also be only a single ochieht or comprise more than two layers, and it should consist of materials with low thermal conductivity. It has been found to be expedient to use a phenolic resin-impregnated flat material made of vegetable fiber for the layers of the leraiiut, v / whether a correspondingly shaped sealing layer 28 or 30 made of an adaptable sealing material is arranged on each side of the laminate, onto which the The sealing layers 28 and 30 are connected to the layers 24a and 24b of the laminate 24 with the aid of an adhesive ₉ the layers (not shown in FIG. 3 for the sake of clarity) ₉ form the layers of the adhesive layer 26 between the layers 24a and 24b resembles _o

Each of the lugs 18 is provided with an oversized opening 32 in which an annular reinforcement element 54 is arranged ₉ which is held firmly in place by friction and / or a chemical bond forms the correct diameter on the iron screw hole for receiving one of the fastening screws 6 according to FIG. 1; the screws 6 are used after the final assembly of the assembly to the flanges mentioned, between which the seal 16 is arranged, firmly together.

2H2U1

to keep. The gain is steep 34 · in the following with further details.

The lower sealing layer JG is essentially flat and covers the core 24 made up of layers Completely; optionally this lower sealing layer 30 be provided with a sealing bead that the Bead 22 on the flat upper side of the seal 16 is similar and also consists of the same material as the Sealing layer 28. Although the bead 22 consists of the same material as the sealing layer 28, it has it has a smaller seal so that it can be compressed or deformed when the carburetor assembly is assembled will. The sealing bead 22 can have any desired shape, its i'orm after the shape of the aligns both flanges of the carburetor assembly between which the seal 16 is located; generally points the bead 22 has no gaps, d. do, it is designed as an endless bead. In some cases it can be useful be to provide beads of a similar type to which the openings $ 2 surrounded in lugs 18. The size and shape of the bead depend on the intended use; in general, the bead can range in height from about 0.125 to 0.380 mm, and in the preferred embodiment the bead has a rounded cross-section with a width of about 1.25 to 2.00 mm. Of course you could within the scope of the invention one also rioted with another Provide height and / or an anoeren cross-sectional shape.

In Fig. 2, the reinforcement member 34 is as massive Component made of a synthetic non-metallic material shown, but it can according to the following description also be designed as a layered association or made of metal or of another solid material be shaped. The desired effect can be achieved with a wide variety of materials, and the reinforcement

209810/1669

parts can be manufactured in a wide variety of sizes and shapes Been

The embodiment described above is the preferred embodiment of the invention, but the invention provides further embodiments, of which two more are shown in FIGS. 4A and 4B. According to the figures, the thermally insulating one Lo! 'Η 40 made from a single piece of flat material, it could also be made up of swel or more individual layers in the above-described ".jiri". In the present ball, however, the central core 40 is formed by a single iochicLt /.eb.il.aet, ie from a material that has a: ": örin..e warmth ability". 3, a commercially available r-.laciiumbei.-ial made from vegetable fibers and impregnated with a resin. The see iabirial has ;; niän ^ - 'Li ch ο ine iJici: e of obwa 2, ^ mm, yet ivini this. Jik- \ a in. ■ ei.-e.Lch der Aruö.bae with d. ^ N! Jchraublc'ci-SiTi ta; f et- - _; a υ, 38 mm verririgorb to condense the kcberial au; this .V -.- johiehb z. 13. with b ^ Ls: of an i-rä ^ b process or by Aufbi-inf _-; .. n of a high pressure. For the execution form according to Fig. ^1, see id eb sicti of that according to Fi ₀ . 2 and 3 in f .-: v: the line dahuroh, ü-Ui the approaches 18 'with the screws! Γ-cherri are formed differently than the described /:n;j:.iLse IS. It is true that the figures do not show that a seal is arranged on both the upper side and the underside of the central core 40, but it should be noted that there are five possible underneath boundaries, only one "; to arrange such a seal.jscniiili.b, which if necessary with a seal sv / ulst, on the upper side or the lower part of the core,

According to Fig. 4A, the mib is provided with a screw hole Approach 18 'formed so that the material of the grain is compressed to a high degree, as it is through

20-9810 / 1669 BAD ORIGINAL

the darker Tup felling is indicated. This expresses. strong compression is achieved in that the volume of the fiber material 40 in the area of the lugs 18 ' Cut through with the screw hole 36 ', apply embossing oil other way is reduced. The upper sealing layer 42 is provided with a seal 44, or a smaller one Has density and is therefore more adaptable than the other parts of this sealing layer. Enjoyment 4A has the sealing layer 42 in the area of the compacted part of the core, and preferably has a greater thickness approximately the same density as the bead 44. On the lower one On the side of the core 40 is another sealing layer 46 arranged, which covers the entire core including the lugs 18 '; each of the two sealing layers 42 and 46 can be bonded to core 40 through a layer of adhesive connected to that in Big, 4A for clarity is not shown »

FIG. 4B shows a construction which is similar to that according to FIG. A, but in which the core 40 made of fiber material has been compressed so much in the area of the attachment 18 'that the outermost part of the attachment 18' has a depression or recess 48, The sealing layers 42 'and 46' and the sealing bead 44 are formed in the same manner as in the construction of FIG. 4A, except that the sealing layer 42 'has a uniform thickness and, apart from the bead 44, a uniform density. To prevent loosening of the fasteners and to ensure a perfect seal when the seal is clamped between the matching flanges of the carburetor ^{cap, an annular insert or washer 5 ° with} a press fit or in some other way is firmly fixed in the recess 48 built-in. Since it is desirable to transfer heat between the metal components between which the invention

209810/1689

BATH

2U2U1

Seal is arranged to restrict as much as possible, it is expedient to make the disc 50 from a metal with low thermal conductivity if the disc is to be made of metal, but it is preferred a high density, highly compressed, resin impregnated asbestos fiber material to use or to mold the disc from a plastic of low thermal conductivity.

5A and 5B show inserts which can be used in particular in the embodiments according to FIGS. 2, 5 and 4B so that the material in the area of the screw holes has a higher density, or so that the fastening means cannot loosen. 5A, the illustrated insert 60 comprises a plurality of layers 62 of a thin, porous asbestos paper with long asbestos fibers 64 which extend at right angles to the axis of the central opening 66. In this construction, the individual layers 62 are combined into a vertical stack and then impregnated in a vacuum; a heat-resistant thermosetting resin, e.g. For example, a phenolic resin is used which, as shown in FIG. A, forms connecting links 68 between the individual layers 62. These connecting members are only indicated schematically in FIG. 5A , that is to say, FIG. 5A does not correspond to a microphotograph which shows the structure that the insert has after impregnation. Here, it is merely stated that a ring or tube shaped layered dressing 60 is obtained in the application of the described method are present in the number of connecting members 68, and which is completely surrounded by a layer of the impregnating material covers _f which is also the wall of the opening 66 . After the various layers 62 have been impregnated in a vacuum or otherwise bonded together with the aid of phenolic resin,

2 0 9 8 10/1669

is an insert 60 compressed and compressed to a significant extent to provide a high strength component which has low thermal conductivity and which is well suited _? to prevent loosening of the fasteners.

5B shows a further embodiment of an insert piece? 0 comprising multiple layers 72 of an asbestos sheet that have been impregnated with a phenolic resin or dipped in a phenolic resin in order to fill the pores with the resin and to cause adhesive layers 7 From the phenolic resin between the layers 72, high pressure is applied to the stack of FIG. 5B so that a highly compacted insert is obtained ₉ which has properties similar to the insert 60 of FIG. 5A.

It should be noted that the inserts of Fig. 5A and 5B suitably post-cured to be used as an insert pieces 34 according to FIG. 3 or as disks 50 according to FIG. 4-B to be usable.

Since it is very desirable to provide adequate thermal insulation between the aforementioned parts of a carburetor assembly, the thickness of the insulating component depends on the available space. structural features of the relevant components as well as the temperatures occurring in the area of the carburetor. Generally speaking, the insulating component should have a low thermal conductivity and its K value should be around I ₁ O to 1.2, but this value also depends on other factors. In general, the insulating component can be built up from one or more layers, depending on the space available and other requirements, as well as the form in which the insulating materials are commercially available. As a mate

209810/1669

. 2H2441

Materials for the insulating core of the seal are all materials of which it has already been established that they meet the requirements listed above. These materials include the well-known synthetic materials; Here, resin-reinforced flat materials made of vegetable fibers or the like have proven to be both practical and economically advantageous. In general, the suitable materials are semi-porous flat materials made of fibers that are reinforced with a thermosetting resin. In some of the described embodiments, in particular in those in which parts of the flat material have to be compressed or compressed to a considerable extent, the compressibility of the insulating core becomes an important factor. As mentioned, the thickness of the insulating layer depends on various factors; In the exemplary embodiments described, it has been shown that it is expedient to use a core made of a fiber material, the thickness of which is now approximately 0.75 to 5.2. Since such a fiber sheet reinforced with a thermosetting resin is compressible, it has only a relatively small amount of the ability to maintain an applied torque, that is, this ability is on the order of 40 % to 50 # when at a temperature of about 120 ° 0 is measured on a core with a thickness of about 3.2 mm, using ASTM test specification F 38, method B; from this it can be seen that it is necessary to compress the approaches of the seal provided with the screw holes, or that it is expedient to use one of the inserts described above. If it is intended to densify the core itself, it must be taken into account that the reduction in thickness is usually in the range of about 0.38 mm.

209810/1669

2H2U1

The materials which are used in the seals according to the invention to effect a seal are generally those materials which are generally used in the field of seals, since these materials have been shown to withstand the stresses to which they are exposed when used in conjunction with carburetors. Typical sealing materials are those made in accordance with US Pat. No. 2,676,099. Furthermore, a sealing material has proven to be suitable which contains mineral fibers and vulcanized nitrile rubber. One such sealing material is marketed in the United States by FDFarnam Co. under the proprietary name "Kaobestos 66015". Further, sealing materials may prove suitable are as described in US Patent 3,158,626 · In other applications, is intended also to the use of other anaterialien seal. The thickness of suitable materials is usually on the order of about 0.5 mm and these materials will be compressed to a thickness of about 0.38 mm when bonded to the core of the gasket. _E

Generally speaking, the sealing materials should however, made of an elastomeric material, so that they can be easily pressed together so that a perfect seal is achieved even when low clamping forces are applied is achieved, and these materials are generally said to be fairly resilient or resilient; h., they should have a fairly low density so that when they are pressed together they rest firmly against the surfaces concerned come. If necessary, you can provide a sealing bead with a sufficient cross section to achieve contributes to the desired sealing effect. Since construct

209810/1669

¹⁵ "2H2U1

tions are to be made to ensure proper sealing, the Diehtungssehicht need or "the seal layers sufficiently adaptable ₉ so that they can be compensated for any deviations _s in the components of the carburetor assembly usually η ansutref = are fen, and in addition to the VJerfefeoff little Have thermal conductivity *

In order for the sealing bead to produce a perfect seal, it can be produced while the parts of a heat-insulating seal according to the invention are combined in the form of iron layers, although both sealing sections can be provided with a sealing bead, but it has been shown ₉ that it is normally sufficient to form a sealing bead only on the upper sealing layer, * Such a bead can be formed in the most varied of ways; in general, a sealing bead proves to be expedient ₀ or a rounded cross-sectional shape with a height of about 0 ^ 125 to 0, 56 mm and a width of about 1 ₉ 25 to 2 ₉ 0 mm _o If the bead is formed from the same material as the corresponding sealing layer, it has a significantly lower density than the sealing material surrounding it, since the material of the bead is formed during the Forming or eating is not squeezed to the same extent as the anger Giving material of the seal =, In this way an adaptable or elastic projection or projection _{9 is created} which ensures the achievement of a perfect seal «,

According to the invention it is proposed that ,, to provide an adhesive layer to form the upper sealing layer and ~ if present - also secure the lower seal layer to the core or _e sow the insulating member; a wide variety of adhesives come in for this purpose

2 0 3 8 10/16

Question, provided that the chosen adhesive creates a firm bond and is not damaged if it is exposed to the operating conditions for which the seals according to the invention are intended. Generally it was found that the neoprenes are capable of producing firm connections, and that in some In some cases, it is advisable to use phenolic resins as well. A preferred adhesive used is a combination of phenolic resin and neoprene, which hardens when they are exposed to a temperature of about 162 to 177 ° C. Here it is preferably ensured that the adhesive or connecting layer between the insulating component and the or each sealing layer only in this way thick is how it is necessary to ensure a proper connection. If such an adhesive is used, the thickness of the tie layer on each layer of material should be from about 0.0075 to 0.018 Do not exceed mm. Adhesives of the same type can also be used to create tie layers between to produce the individual layers of the core or the insulating component, if it is desired, a to build up such a core from several layers, since the flat materials available on the market are not sufficient Have thickness.

There are several elastomer and resin compounds available, each of which has particular advantages. Here it is only important that it is possible to apply the adhesive in the form of a continuous thin layer, and that it has such properties that it can be dried or partially cured for ease of handling before the final assembly of the invention To allow seals, and that the adhesive after the final hardening or after a connection has been made between adjacent layers of the core or

209810/1669

2U2U1

between the core and one or more sealing layers Withstands the conditions to which it will be subjected when used in conjunction with a carburetor assembly is. Also in U.S. Patent 3 158 626 elastomer compounds described for use are suitable for the seals according to the invention.

As already briefly indicated, there are various options available to achieve the desired results, ie to give the seals the desired properties to the maximum extent so that the fastening means do not loosen. One of these possibilities has already been mentioned, namely the compression of the insulating component itself in the area of the screw holes, as described in E ¹ Ig. 4A is shown. Another way of achieving essentially the same effect is to compress the zone in question to such an extent that a recess is formed which, in the manner shown in FIG. 4B, can receive an annular or tubular insert which is optionally covered by a sealing layer, whereby the insert piece can consist of metal, a solid molded plastic or layers of asbestos paper, asbestos flat material and the like impregnated with phenolic resin If these inserts are made of metal, they can largely resemble bushings, washers and similar components, and they are made of steel or similar metals, which preferably have a low thermal conductivity, or in which the K value is low. In many cases, the thickness of the inserts can be one-half or three-quarters the thickness or more than the total thickness of the finished insulating gasket, which is generally about 2.9 to 3.05 mm thick. In the preferred embodiment, an asbestos sheet insert is installed in an oversized screw hole

209810/1669

-ι ο

* 2H2A41

and frictionally held therein, the thickness the insert corresponds approximately to the total thickness of the finished seal; during the manufacturing process has a such insert, however, a z. B ^ about 0.125 mm less Thickness so that there is compression of the heat insulating gasket structure during the manufacturing process limited. Since the other materials of the seal are compressible, while an insert piece is made of metal or a highly densified phenolic resin impregnated asbestos material by comparison substantially is not compliant, the incorporation of such an insert prior to reducing the volume of the Materials by applying pressure to the overall structure that the extent to which the entire structure is limited Construction can be compressed. In the following, when dealing with the manufacturing process, these Point dealt with in more detail.

However, in the preferred embodiment which uses a separate non-metallic insert is, the insert comprises several layers of asbestos paper or asbestos cardboard with a thermosetting Phenolic resin are saturated or impregnated. The number of layers is preferably kept as small as possible, however, the number of layers is usually determined by the thickness or height of the insert in the particular one heat-insulating seal construction should receive. The heat-resistant, thermosetting phenolic resin provides the required strength and torque capacity, and in a preferred embodiment when using asbestos paper or asbestos cardboard, the fibers have a relatively long length, and they extend at right angles to the clamping force or, at right angles to the axis of the formed in the insert Screwless. Even when using others

209810/1669

-W- 2U24A1

Flawless results can be achieved with non-metallic fibers. Once a layered dressing has been built up, it is subjected to a pressing operation ₉ which results in a substantial reduction in thickness to 40 % or more of the original thickness, resulting in a highly compressed and dense _? non-metallic insert gives ₉ which can be cured _s to complete curing of the phenolic resin or other material to ensure that was used in the preparation of the insert ,, Non-metallic inserts made of asbestos fibers and phenolic resin normally have a density or specific gravity of about I ₃ 92, a thermal conductivity or K-factor of about 2 to 2.5 compared to about 50 for steel, high compressive strength and also good chemical resistance under the operating conditions to which the seal is exposed. Furthermore, these inserts preferably withstand torque loads of about 1050 to 1400 kg / cm.

Taking into account the properties of the materials from which the seals according to the invention are made and which have been described above will be referred to in the following process of the invention for the preparation such seals received, whereby reference is also made to the information already given »

In the following example, assume that a gasket is to be made that has one core of two Layers as well as an upper and a lower layer of sealing material. A suitable cover material that is generally somewhat thicker than usual, especially if a sealing bead is to be produced cut to the right width, which depends on the width of the core or the heat-insulating component. In some cases, however, it is also the case with the commercial

209810/1669

-20, 2H2441

usual ^ resin-impregnated fiber flat materials required to cut them to the correct size, d. That is, in these cases too, the dimensions depend on the size and shape of the heat insulating material to be produced Seal construction. After z. B. a sealing layer and the heat insulating sheet on the right Width have been cut out, a first is made Laminate is made by removing the cover material from a supply roll peel off and bond it to a piece of core material that is a length using an adhesive of about 2300 mm, and the thickness of which corresponds to about half the thickness of the finished core, the cover material is periodically cut from the material of the supply roll, so that one more with the sealing material covered pieces of core material. Then who these pieces each on their of the cover material the opposite side is provided with a thin coating of an elastomer and resin adhesive, whereupon the Allow the coating to dry. After sufficient drying, the core parts provided with the sealing material can be removed combine into a layered dressing using the adhesive layer and the finished product produced Cut to the desired width.

The finished laminate produced in this way can then be cut to size with the aid of punching tools or the like that it is given its final shape and provided with oversized screw holes that later pick up non-metallic inserts which have screw holes of the correct diameter. Ever Depending on the desired total thickness, the heat insulating gasket can have two layers of the core material or only such a layer or more than two layers. If more than two layers are used, then also the inner layers of the core material

209810/1669

142441

Apply a thin coating of the adhesive on both sides in the above-mentioned version.

The thickness of the adhesive layer must be adequately controlled so that the thickness of any of these layers is not observed does not exceed a level of about 0.0075 to 0.0178 ram. A layer of adhesive twice the thickness would be there arise where two surfaces coated with the adhesive are brought into contact with one another.

Next, the layered dressing is subjected to a hot pressing operation using a die with guide pins in which the upper half of the mold has a groove which serves to give the sealing bead of the upper sealing material layer its final shape. Before the hot pressing process is initiated, however, it is preferred to install the non-metallic bushings or inserts, which act as calibration means and determine the overall thickness of the finished seal, since they are hardly compressible in comparison to the remaining parts of the seal. This method makes it possible to produce seals according to the invention in which very tight tolerances with regard to the thickness can be maintained. In cases where it proves to be expedient, it is of course also possible to install the inserts in the seals only after the hot pressing. During hot pressing, the thickness of the layered dressing is significantly reduced and therefore the inserts may have a thickness or height slightly less than the total intended thickness of the finished gasket, as shown in FIG the correct dimensions. The sealing bead is best produced with the aid of a groove formed in the upper mold half and by a slight increase in the volume of the cover material and the core in the range of 5 % to 10 %

209810/1669

-22- 2H2U1

Pressing process is brought to its final density, so that an adaptable and deformable bead is formed. If the insulating component itself is to be compacted in the area of the screw holes, this can of course be done achieve by giving these parts of the insulating member a greater thickness, so that these parts or Zones are then condensed to a considerably greater extent than would be the case if the iaaLende Component as such should not be compacted. As can be seen from the drawings, it is of course possible at the same pressing process to ensure that a recess is created by partially compressing the material, in which a metallic or non-metallic insert can also be installed. As mentioned, it is possible to insert the inserts after the completion of the pressing process or before the pressing process or at the time of the pressing process. During the hot pressing, a pressing time is maintained, which depends on the thickness in the area aligns the connection line, maintaining a temperature sufficient to keep all of the components of the bandage to harden, fix or otherwise reliably connect with one another »If a binding agent If epoxy resin-based adhesive is used, it need not necessarily be required to perform a hot-pressing operation to perform or to work with an elevated curing temperature, since such resins usually contain a curing agent or a catalyst so that it is not necessary to use heat, pressure or the like to bring to effect.

The heat-insulating gasket can then be used if necessary post-cure and insert 34 can be pressed in, if not already forms part of the seal. This step can be done manually or semi-automatically or in some other way be performed; these and other variations that stand out

209810/1669

-23- 2U2441

according to the respective construction ₉ are obvious to any person skilled in the art, if one takes into account the throw of ie used and the washed end result

In a modified method according to the invention, the non-metallic inserts or disks are made from asbestos cardboard which contains long asbestos fibers which are connected to one another with the aid of starch or another binder of a known type the asbestos cardboard is preferably impregnated with phenolic resin under the influence of the _{negative pressure δ so} that the resin content corresponds to about 10 to 30 percent by weight of the asbestos cardboard and preferably about 20 to 25 percent by weight. The resin is a mixture of water used in form ₅ alcohol and Phenolhars "laughing impregnating the asbestos board with the Phenolhars ia vacuum the asbestos board at a low temperature dried and ge in a cool room at a temperature of about 1 to 10 C = layered in order to essentially interrupt the hardening of the hardening in the air »

The panes are then punched out of the asbestos cardboard using punching tools and then inserted into the associated openings in the seal! then the gasket is then placed a mold with a guide pin, wherein the plunger that comes in Bemch of the guide pin into effect, is added as ₉ that the greater thickness of the discs is taken into account, "Kunmehr closes the mold under application of pressure, but not too quickly, as it has been shown that the resin needs a certain time to flow laterally into the adjacent sealing structure and to bond with it, which happens at temperatures between about 65 ° and 177 ° C. This process usually takes about 5 to 10 seconds.

209810/1669

After the washers have been installed in the seals, the connecting surfaces between them will form the core Layers as well as between the sealing or facing material layers and the core at a temperature of about 135 ° C cured for about 10 to 15 minutes to degas the material, whereupon the temperature increased to about 150 ° to 195 ° C is increased to complete the curing.

Instead of the non-metallic disks in the manner described above during the hot pressing of the entire To compress and compress the seal, it is of course also possible to complete the panes and cure before they are in the heat insulating gasket may be installed using an interference fit to hold the washers in place in the seal will.

6 to 9 show a further embodiment of the invention, in which the core, designated as a whole by 85, consists of asbestos cardboard, as is used in essentially the same manner in the manufacture of the insert pieces 34 described above. To manufacture the core 85, two or more e.g. B. with the help of punching tools cut asbestos cardboard pieces 86 which are impregnated with the aforementioned mixture of water, alcohol and phenolic resin; The pieces of material 86 are placed on a heated mold with guide pins, a disk-like component 87 (FIG. 8) being arranged between the pieces of material, and a piece of sealing material 88 or 89 cut out with the aid of a punching tool resting on each of the two outer surfaces. The core parts 86 have aligned openings 90, the diameter of which corresponds to the outer diameter of the screws by means of which the associated metal flanges are clamped together, and the disk-like component 87 »

209810/1669

2U2U1

which also consists of asbestos cardboard and with the phenolic resin containing mixture is impregnated, has an opening 91, the diameter of which is also the diameter of the clamping screws is equivalent to. The outer diameter of the disc 8? is approximately the same as that of the inserts 34 of the Pig embodiment. 2 and 3 * and the layers 88 and 89 can be made of the same sealing material as layers 28 and JQ of the embodiment 2 and 3, the sealing parts 88 and 89 are so cut so that they receive openings 92 "which approximately have the same diameter as the disks 8 ?, so that when hot pressing the sealing parts in the form for Making the finished seal of the core 85 essentially becomes homogeneous and has ν projection © 93 and 94, that through the openings 92 of the sealing material layers 88 and 89 protrude outwards »with the density of the core in the is essentially the same as that of the inserts 34. After hot pressing, the composite gasket can to be finally hardened

Of course, the core will be 85 and the thread sleeves (and) 8.8 and 89 when cutting also with the other openings provided as it is necessary to the in fig «.6 shown form.

During the pressing process, both cover layers 88 and 89 or just a top layer, on their outside. provided with an endless bead 95 ;; this happens in in the manner described with the help of to the relevant Areas of the form of hats «. In some cases it is also useful near the outer band of the seal to one; several small purposes to be explained Form projections or buttons, during the pressing process can be produced in the same way as the bead 95.

2Q9810 / 166 &

The main purpose of the method of forming a heat insulating gasket just described is to to have the effect that when the flanges 3 and 7 (Fig. 1) are braced together with the aid of the screws 6, as is also shown in Fig. 9, the inner surfaces of the flanges 3 and 7 come to rest on the projections 93 and 94, so that all parts are firmly clamped together and the screws cannot loosen, whereby the bead 95 on one side or on both sides of the seal seals the opening 97 from the atmosphere, and air gaps 98 remaining between the metal flanges and the gasket. When the protrusions are provided, they help to ensure that the air gap is maintained when the distances between the screws and the properties of the flange surfaces are such that warpage could result in the flange surfaces come to rest on the main part of the seal. Experiments have shown that the heat transfer at a such a seal is significantly reduced if it is ensured that the contact surfaces of the flanges 3 and? not come into face-to-face contact with facings 88 and 89 of the composite gasket, and that presence an air gap on the order of 0.25 mm or less in width results in a significant increase in the insulating capacity of the assembled gasket leads.

While it is preferred to actually maintain an air gap of the type shown at 98 between the flanges and the gasket, some benefit is obtained even if some amount of surface contact occurs as long as there is no pressure contact between the surfaces. For this reason, in this embodiment of the invention, the outer surfaces of the cover layers 88 and 89 should be in alignment with Ö.en

203810/1869

Front faces of the projections 93 and 94 stand or be offset somewhat inwardly with respect to these outer faces; this is in contrast to the embodiment according to FIGS. 2 and 3, in which it is intended that the cover material is somewhat compressed when the parts are clamped with the aid of the screws 6.

To give an example to which the invention is not limited, it should be mentioned that it is Has proven useful, an air gap 98 with a Provide width in the order of 0.125 to 0.25 now, the free height of the sealing bead 95 by about 0.125 to 0.175 mm larger than the intended width of the air gap, so that the bead when bracing the Parts is compressed to such an extent that the contact surfaces of the flanges 3 and 7 to rest against the Projections 93 and 94- come so as to create the desired air gap 98 to be delimited. If protrusions 96 are provided, the normal free height of these protrusions may be about 0.05 up to 0.10 mm less than the height of the bead, and when the parts are clamped, these projections would then be somewhat pressed together until the air gap has reached the desired width.

The bead 95 is formed in the same way as the bead 22 of the seal according to FIGS. 2 and 3 »and he has a lower density than the other parts of the cover material when the seal is in the manner described has been made.

In some applications it can be useful instead of the protrusions or buttons 96, an endless bead to provide which extends along the outer edge of the composite seal and opposite this edge z. B. is now offset by about 3.2 inwards. This bead would can be made in the same way as the bead

209810/1669

-28- - 2H2U1

95 »but it would have the same height as the buttons 96, and it would not only form a stop that ensures that the air gap is also retained at points removed from the tensioning screws, but it would In addition, protect the exposed surfaces of the sealing material against external influences and thus for extension contribute to the service life of the seal.

Although the core 85 2 and 3 is preferably made in the manner described, asbestos cardboard, but it is also possible to make the reference to FIG. Core-described use, wherein the inserts are 3 ^ dimensioned ^such that their outer surfaces either in alignment with the Outer surfaces of the cover layers 28 and $ 0 stand, or that they protrude slightly beyond the cover layers, in order to bring about the desired improvement in thermal insulation.

When the inserts J4- over the outer surfaces of the Cover layers protrude, or if the projections 95 and 94 have a corresponding height, the importance is reduced of buttons 96, so that in most cases they can be omitted.

Finally, it should be noted that in the embodiments described above, the most varied of modifications and can provide modifications without departing from the scope of the invention.

Expectations;

209810/1669

Claims (1)

si - 2H2441 ANEPSÜÜil 1 *) Seal for use with motor vehicle engines and the like characterized by a heat-insulated ends, the first component (24) and an ab " seal effecting second component (28) j where the forms the first component of Ümfangsabschhitte, the holding means (6) and can thus be held within an assembly (2), and the density of this "Um * catching sections is considerably greater than the density of the remaining parts of the two components * 2 * Seal according to claim 1, characterized in that g e k e η η « draws that the higher density of the catchment sections is achieved in that the volume of the material of the first component (4Ö) lift Se ^ eiöh dei? Extent « sections by squeezing ^ obtained3? t has been * ^ i seal according to claim 2 _S thereby characterized geke η η * _t that the mentioned Ümfangsäbsohhitte have been compacted so »DAB each ÖIE a recess (48) _i delimit and that in each of these recesses, an insert piece (50) of a material of hoheä? Density is built in * 4 # seal according to claim 1, characterized in that the outer circumferential sections by non-metallic inserts (345 60; 7Q) from one Material of high density are formed, which are frictionally held in oversized screw holes (32) are. 5 * Seal according to claim 4 _f, characterized in that the second component (28) is provided with a sealing bead (22) which consists of the same material, but whose material has a small 2 0 9810/1 2U2U1 The density of the other parts of the component is higher than that of the material j and that the Dichtungswül st is shaped * that ei * a protruding sealing cut, which a considerable part of an opening to be sealed (20) encloses " 6. Seal according to claim 5 »characterized! that a third component (JO) consists of a sealing material is attached to the first component (24) so that the first component part is between the second component (28) and the third component Forms lying visual layer. 7 * Seal according to claim 1, since it shows that the insert piece (54; 60; 70) is ring-shaped and made of fiber materials reinforced with resin consists. 8. A seal according to claim 7 * characterized in that the insert piece consists of layers (62; 72) composed * 9. Seal according to claim 8 | characterized in that all components of the seal köhgiuönt are* 10. Seal according to claim 9 * characterized in that the outer end faces of the insert piece are essentially flush with the top and bottom of the layered dressing that is made up of the first, second and third components. 11. Heat-insulating seal * marked by a heat-insulating component (24) from chosen thickness and Ümrißföria with a central opening 209810 / 1S69 ■,: \. : ■; - 5ΐ - - - 2Η2Α41 (20) and several along its circumference .distributed at intervals Screw holes (32) whose diameter is greater than it is necessary to take up the associated screws (6), in which case a non-metallic, with the screw hole generally congruent annular insert (34-; 60; 70) is arranged, which has a high compressive strength and has a low thermal conductivity and a screw hole (36) with a diameter of the to be received Schiaube has a corresponding diameter, furthermore by one on at least one side of the heat-insulating Constituent sealing material layer (28, 30) having generally the same outline shape as the aforesaid Component, wherein the or each layer is firmly glued to the component, and by an endless sealing bead (22) formed on at least one of the sealing material layers and opposite the central one Opening is slightly offset to the outside and surrounds this opening. 12. Seal according to claim 11, characterized in that the heat insulating component has such a thickness that it prevents the transfer of heat between components (3, 7) made of metal, between which the seal is installed. 13. Seal according to claim 12, characterized in that the heat insulating component consists of a fiber surface material, which with a means Heat curable resin is impregnated. 14. Seal according to claim 12, characterized in that the annular insert pieces (34) have a thickness that is less than the thickness of the entire seal (16), or which is substantially equal to this thickness. ; ■ 209810/1669 -32- 2 U 2 A 4 15 · Seal according to claim 14, characterized in that the annular insert (60) comprises a plurality of layers (62) of asbestos paper impregnated with a resin. 16. Seal according to claim 15, characterized in that g e k e η η ζ E i chn et that the asbestos paper contains long asbestos fibers (64) which are at right angles to the axes of the screw holes (66) extend. 17 · Seal according to claim 16, characterized in that g e k e η η, that the resin is a cured phenolic resin. 18. Seal according to claim 12, characterized in that the sealing bead (22) by a Part of the sealing material layer (28) is formed, which has a lower density than the other parts of the Sealing material layer. 19 · Seal according to claim 18, characterized in that the sealing bead (22) in cross section is substantially semicircular, and that it has such dimensions that it is substantially complete Sealing is achieved when the seal is clamped between adjacent components (3, 7) in order to fulfill its purpose is. 20. 'Seal according to claim 19, characterized in that on the of the sealing bead (22) facing away from the heat-insulating component (24) a second sealing material layer (30) is arranged is. 21 ο Heat-insulating gasket for carburettors in motor vehicle engines and the like by a core (40) made of a Paser flat material 209810/1669 and layers of sealing material (42, 46), both of which consist of an elastomer material and are connected to the top and bottom of the core, respectively, the core and the layers of sealing material having a plurality of coaxial through openings (36 ') for receiving screws (6), and wherein the zones of the core material immediately surrounding the screw holes have a significantly higher density than the remaining parts of the core material, 22. A heat-insulating seal for the carburetor of automotive engine en and the like, gekennzei ch -> net by means of either a core (40) consists of a ffaserflachmaterial and sealing material layers (42, _46)% with the top, the bottom of the core material are connected and from a Consist of elastomer material, the seal having several screw holes (36 *) near its circumference, and the core material in the vicinity of the screw holes having a considerably greater density than the other parts of the core « 23 · Seal according to claim 22 ,. characterized in that the compacted zones in the vicinity of the screw holes (36 *) a non-metallic, in highly compacted, resin-impregnated and hardened material, whose thermal insulation factor is below the value 3 is. 24. Heat insulating seal for carburetors and the like with a core of 4 layers of sealing material on both flat sides carries, the seal with screw holes ■ and a central to be sealed off from the outside opening is provided, characterized in that the core (85) in the vicinity of the screw holes (90) has a K-factor of less than 3 that the thickness of the Core within these zones is greater than the total thickness 209 «1 0/1 BESt 2H2U1 the adjacent zones of the composite gasket that the or each layer of gasket material (88,89) in the vicinity the central opening (97) is provided with a sealing bead (95), and that the total thickness of the seal in The area of the sealing bead is slightly larger than the thickness of the core in the vicinity of the screw holes, so that then, when the composite seal is clamped between the puddles of two components (5, 7), between one of the Flanges and the adjacent sealing material layer an air gap (98) remains. 25. Seal according to claim 24, characterized in that the core (85) consists of a hardened, Resin-impregnated asbestos fiber sheet. 26. Seal according to claim 24, characterized in that the width of the air gap (98) is about 0.125 to 0.25 mm. 27 · Seal according to claim 24, characterized in that the upper and lower sealing material layers (88, 89) With a sealing bead (95) is provided. 28. Seal according to claim 24, characterized in that the height of the sealing bead (95) is selected in the relaxed state so that the sealing bead is compressed by about 0.125 to 0.178 mm is when the flanges (3j 7) of the associated components are braced together. 29. A seal according to claim 24, characterized in that the or each sealing material layer (88, 89) near the outer hand of the seal with additional projections (96) is provided. 2 0 8 8 10/1689 -35- 2U2A41 30. Heat insulating seal, marked by a main component (24) made of a heat-forming material, which has the desired outline shape is cut to size and provided with oversized screw holes (32), in which oversized holes are non-metallic Sockets (34 ·; 60; 70) are arranged, the The inner diameter corresponds approximately to the diameter of the screw (6) to be accommodated, and the bushings consist of a Highly compacted, hardened, resin-impregnated insulating material. 31. Seal according to claim JO, characterized in that at least part of the main component (24) made of a compressible elastomer material (28, 30), the thickness of which is chosen so that it protrudes beyond the upper end faces of the sockets. 32. Seal according to claim 30, characterized in that g e k e η η ζ calibrates that the K-factor of the sockets does not exceed the value 3. 33. Seal according to claim 31 _? characterized in that measures are taken to retain the sockets in the oversized screw holes of the main body of the gasket. 209810/1669 Blank page