US2954763A - Unitary exhaust manifold gasket and heat shield - Google Patents

Description

1960 R. H. MALCOLM 2,954,763

UNITARY EXHAUST MANIFOLD GASKET AND HEAT SHIELD Filed April 29, 1959 2 Sheets-Sheet 1 A r romvzr UNITARY EXHAUST MANIFOLD GASKET AND HEAT SHIELD Filed April 29, 1959 Oct. 4, 1960 R. H. MALCOLM 2 Sheets-Sheet 2 ATTORNEY INVENTOR B06621 H ZZZczZwZm PM 0 United States Patent Q T UNITARY EXHAUST MANIFOLD GASKET AND HEAT SHIELD Robert H. Malcolm, Fort Wayne, Ind., assignor to International Harvester Company, Chicago, 111., a corporation of New Jersey Filed Apr. 29, 1959, Ser. No. 809,827

9 Claims. (Cl. 123-198) the connections of the electrical conducting cables attached to the spark plugs which cables and spark plugs form a part of the engine ignition system, are often times adversely effected by the heat radiated from the exhaust manifold during operation of the engine. This is especially true in heavy duty engine installations such as those employed in motor trucks wherein the vehicle is operated for long periods of time under maximum load conditions. It has been found that the heat radiated from the exhaust manifold often times is of such intensity as to contribute to the failure of the ignition system by deteriorating the cable insulation and the mechanical and electrical connections of the cables to the spark plugs. It is, therefore, a primary objective of the present invention to mitigate the damaging influence of the heat radiating from the exhaust manifold on the ignition system cables and the mechanical and electrical connections thereof to the spark plugs by providing a protective heat shield or baflie spaced between the exhaust manifold and the spark plugs.

A further object is the provision of an exhaust manifold gasket having a heat shield incorporated therein for preventing the ignition system cables and the connections thereof with the spark plugs from over heating.

A still further object is the provision of a unitary exhaust manifold gasket and protective heat shield which is simple and durable in construction, economical to manufacture and which does not interfere in any way with the normal operation of the engine in which it is incorporated.

Still another object of the invention is to provide a protective heat shield which is attached to the engine when the exhaust manifold is assembled on the engine and which does not interfere with the removal, replacement or adjustment of the spark plugs.

The foregoing and other important objects and desirable features inherent in and encompassed by the invention together with many of the purposes and uses thereof will become readily apparent from a reading of the ensuing description in conjunction with the annexed drawings in which: 7

Figure 1 is a side elevational View of an internal combustion engine embodying the invention;

Figure 2 is a sectional view taken substantially along line 22 of Figure 1;

Figure 3 is an enlarged top plan view of the unitary exhaust manifold gasket and heat shield detached from the engine;

Figure 4 is a bottom plan view of the unitary exhaust manifold and heat shield;

Patented Oct. 4, 1960 Figure 5 is. a sectional view taken substantially along line 55 of Figure 4; and

Figure 6 is a fragmentary sectional view taken substantially along line 6-6 of Figure 4.

Referring to the, drawings in detail wherein like reference characters represent like elements throughout the various views, there is partially shown a conventional V-type internal combustion engine 10 which includes a cylinder block 11 having two rolls of cylinders 12, only one of which is shown in the drawings, arranged at an angle with respect to each other. Secured to each roll or bank of cylinders 12. is a cylinder head 13. A piston 14 is reciprocal in each cylinder 12 and the top of the piston and the surface 15 on the underside of the cylinder head 13 in alignment therewith form a combustion chamber 16. The cylinder head 13 is provided with an air fuel intake passageway 17 which has one end in communication with the combustion chamber 16 and its opposite end in communication with an intake manifold 18. ,An intake valve 19 controls the flow of charge from the intake manifold 18 to the combustion chamber 16 in a conventional manner. A plurality of spark plugs 20 are threaded into recesses formed through the cylinder head 13 and each spark plug has its electrode disposed within a respective combustion chamber 16 for igniting the air fuel charge within the combustion chamber. The above described engine structure is conventional and forms no part of the present invention. The hot prodnets of combustion are emitted from the combustion chamber 16 through passageways provided in the cylinder head 13 which are in communication with an exhaust manifold 21.

Releasably attached to the outer terminal end of each spark plug 20 is a high tension cable 22. The opposite end of the high tension cables 21 are connected with the engine electrical ignition system distributor (not shown) in an old and well known manner. Each high tension cable 22 comprises a metallic conductor or wire molded or otherwise embedded in a sheathing or cover 24. The ends of the cables 22 are provided with enlarged contacts 25. Each cable 22 is attached to the respective spark plug 20 by means of a substantially tubular connector 26 which frictionally grips the outer covering 24 of the cable 22 and the outer terminal end of the spark plug 20. The connectors 26 are sufficiently flexible to tightly embrace the outer covering 24 of the cable and the terminal end of the spark plug 20 to maintain a good electrical contact between the enlarged contact 25 and the tip portion 27 of the spark plug outer terminal as shown in Figure 2. The connectors 26 maintain the electrical contact between the contacts 25 and the tips 27 of the spark plugs 20 and such electrical contacts are protected from their deleterious effects of dust, dirt and oil. Of necessitythe connectors 26 and the outer casing 24 of the cables 22 are made of material such as rubber or other material having like physical characteristics which is incapable of conducting electric current and is flexible to a certain degree without being broken, cracked or distorted. It is well known that such materials when subjected to over heating for long periods of time tend to become brittle and crack and lose their resiliency as well as their electrical insulating properties. When this occurs the connectors 26 lose their ability to maintain the contacts 25 firmly into engagement with the tips 27 of the spark plugs 24), and the dielectric characteristics of the insulating covers 24 of the cables 22 and the connectors 26 deteriorate and lose their ability to prevent electrical leakage to the surrounding metal parts of the engine with the result that the engine ignition system is adversely effected and functions improperly. In order to obviate these difficulties, the present invention contemplates the provision of a unitary exhaust manifold gasket and heat shield, shown in Figures 3 and 4. A generally flat elongated section 28 of the unitary exhaust manifold gasket and heat shield is provided with a plurality of spaced openings 29 therethrongh encircled by an embossment 30 as in conventional exhaust manifold gaskets. The flat section 28 as well as the heat shield, designated generally by numeral 31, of the unitary exhaust mamfold and heat shield, is made of sheet metal or the like as used to. construct conventional intake exhaust manifold gaskets. One side of the section 28 is adapted to bear against a flat surface 32 formed on the cylinder head 13 with the openings 29 in registration with exhaust passageways (not shown) leading from the combustion chambers 16 and opening into the surface 31. As in conventional engine installations, the exhaust manifold 21 is mounted on the surface 32 of the cylinder head 13 with the fiat section 28 sandwiched thereinbetween. The cored passageways formed in the exhaust manifold 21 are in communication with the openings 29 in the section 28 and the exhaust passageways formed in the cylinder head 13 for conveying the hot products of combustion to the atmosphere. It is believed obvious that during operation of the engine heat is radiated from the exhaust gases flowing through the exhaust manifold 21 and, because of the close proximity of the spark plug terminals 27, connectors 26, and the ends of the cables 22 to the exhaust manifold, there is a tendency for the sheathing 24 and the connectors 26 to overheat and deteriorate. The heat shield or baffie 31 is integrally formed with and extends from one longitudinal edge of the flat section 28. As best shown in Figure 2, the major portion of the heat shield 31 lies substantially in a plane angularly disposed With respect to the plane of the flat section 23 and when the unitary exhaust manifold and heat shield is mounted in position the major portion of the heat shield 31 is spaced from and overlies the uppermost surface of the exhaust manifold 21. Integrally formed with and extending angularly from the general plane of the major portion of the shield 31 are a pair of spaced cars 32 which, in turn, have substantially flat tabs 33 formed on the free ends thereof. The tabs 33 lie in a plane substantially parallel and spaced from the flat gasket section 28 and each tab 33 is provided with an aperture 34 which is in vertical alignment with a respective aperture 35 formed in the flat section 28. Each tab 33 is also provided with an elongated slot 36 spaced from the aperture 34 formed therein for a purpose which will be explained hereinafter. Each cored passageway formed in the exhaust manifold 21 has an end thereof defined by a peripheral flange 37, a portion of such flange 37 being shown in Fig. 2. The flanges 37 are provided with a flat surface 38 which bears against the fiat section 28 of the unitary exhaust manifold gasket and heat'shield. The manifold 21, as in the construction of conventional exhaust manifolds for V-type internal combustion engines, is provided with enlarged bosses 39 on each end thereof. An attaching bolt 40 extends through a central bore formed in each boss 39 and is threaded into a threaded recess formed in the cylinder head 13. The attaching bolt 40 also extends through an aperture formed in an L-shapcd lock washer 41 which is compressed between the head 42 of the bolt and the boss 39' when the bolt 40 is drawn up tightly. The short leg 43 of the lock washer 41 bears against a flat surface 44- of the boss 39, as best shown in Fig. 2. Once the bolts 40 are drawn up properly the free end portion 45 of the longer leg of the lock washer 41 is bent substantially 90 to engage a flat on the head 42 of the bolt 41. Thus the bolts 4% are prevented from unthreading from the threaded recesses formed in the cylinder head 13 during operation of the internal combustion engine 10. A mid portion 46 of the exhaust manifold 21 is in the form of a substantially fiat flange having an opening extending therethrough adapted to register with an aperture 47 formed in the fiat gasket section 28 of the unitary exhaust manifold gasket and heat shield when the section 28 is correctly positioned on the cylinder head surface 32. An attaching bolt 48 extending through the opening and the aperture 47 into a threaded recess formed in the cylinder head 13 is utilized to clamp the mid portion 46 of the exhaust manifold 21 to the cylinder head 13. A lock washer 49, similar to the lock washers 41 described hereinabove, is employed to prevent unthreading of the attaching bolt 48 from its mating recess in the cylinder head 13. The exhaust manifold 21 is also provided with a pair of enlarged, integrally-formed cylindrical bosses 5G, each of which is spaced substantially midway between a respective end boss 39 and the flange 46. With the unitary exhaust manifold gasket and heat shield correctly in place on the internal combustion engine 10 each tab 33 overlies the flat outer end of a respective boss 51'}, as shown in Fig. 2, with the aperture 34 thereof in registration with a central bore formed through the boss 50. Each central bore is also in alignment with a respective aperture 35. Extending through each aperture 34 and the aperture. 35 associated therewith and the central bore of a respective boss 50 is an attaching bolt 51 which is threaded into a recess formed in the cylinder head 13. An L-shaped lock washer 54 is interposed between the head 52 of each attaching bolt 51 and the outer surface of the tab 33 with the relatively shorter leg 53 thereof projecting through a respective slot 36. The free portion 55 of the relatively longer leg of the lock washer 54 is bent upwardly away from the tab 33 to bear against a fiat surface of the bolt head 52 to prevent unthreading of the bolt 51.

From the foregoing, it will be appreciated that the unitary exhaust manifold gasket and protective heat shield not only function as a gasket for sealing the joint be tween the exhaust manifold and the cylinder head but also as a protective heat shield to prevent the connectors 26 and the insulating cover 24 of the cables 22 from overheating which is simple and durable in construction, economical to manufacture and assemble on the engine and which does not interfere in any way with the operation of the engine.

The embodiment of the invention chosen for the purposes of illustration and description herein is that preferred for achieving the objects of the invention and developing the utility thereof in the most desirable manner, due regard being had to existing factors of economy, simplicity of design and construction, and the improvements sought to be effected. It will be appreciated, therefore, that the particular structural and functional aspects emphasized herein are not intended to exclude, but rather to suggest other adaptations and modifications of the invention as fall within the spirit and scope of the invention as defined in the appended claims.

What is claimed is:

1. In an internal combustion engine having a cylinder head provided with a substantially flat surface; an exhaust manifold mounted on said flat surface having passages therethrough in communication with the interior of said cylinder head for conducting hot products of combustion from the engine; an electrical ignition system including a plurality of spark plugs attached to said cylinder head adjacent a longitudinal edge of said flat surface and a plurality of electrically insulated, electric current conducting cables, each of said cables having an end thereof electrically and mechanically connected to the outer terminal of a respetive spark plug; a unitary exhaust manifold heat shield including a flat gasket section interposed between said exhaust manifold and said cylinder head flat surface and a heat shield integrally formed with one lonigtudinal edge of said flat gasket section extending outwardly from said one longitudinal edge of said flat surface and being spaced between said exhaust manifold and spark plug terminals and cable ends, said heat shield including a pair of longitudinally spaced tabs lying substantially in a plane parallel to the plane of said flat gasket section; and means for attaching said exhaust manifold to said cylinder head including a plurality of attaching bolts, certain of said bolts extending through said tabs and said fiat gasket section.

2. In an internal combustion engine having a cylinder head provided with a substantially flat surface; an exhaust manifold mounted on said flat surface having passages therethrough in communication with the interior of said cylinder head for conducting hot products of combustion from the engine; an electrical ignition system including a plurality of spark plugs attached to said cylinder head adjacent a longitudinal edge of said fiat surface and a plurality of electrically insulated, electric current conducting cables, each of said cables having an end thereof electrically and mechanically connected to the outer terminal of a respective spark plug; a unitary exhaust manifold heat shield including a flat gasket section interposed between said exhaust manifold and cylinder head flat surface and a heat shield integrally formed with one longitudinal edge of said flat section extending away from said one longitudinal edge of said flat surface and being spaced between said exhaust manifold and spark plug terminals and cable ends; and means for attaching said exhaust manifold to said cylinder head including a plurality of attaching bolts, certain of said bolts extending through said heat shield and said flat gasket section.

3. In an internal combustion engine having a cylinder head provided with a substantially flat surface; an exhaust manifold mounted on said flat surface having passages therethrough in communication with the interior of said cylinder head for conducting hot products of combustion from the engine; an electrical ignition system including a plurality of spark plugs attached to said cylinder head adjacent a longitudinal edge of said flat surface and a plurality of electrically insulated, electric current conducting cables, each of said cables having an end thereof electrically and mechanically connected to the outer terminal of a respective spark plug; a unitary exhaust manifold heat shield including a flat gasket section interposed between said exhaust manifold and said cylinder head flat surface and an integrally formed heat shield extending from one longitudinal edge of said flat section and being spaced between said exhaust manifold and spark plug terminals and cable ends; and means for attaching said exhaust manifold to said cylinder head, said means also serving to attach said unitary exhaust manifold heat shield to said cylinder head.

4. In an internal combustion engine having a cylinder head provided with a substantially flat surface; an exhaust manifold mounted on said flat surface having passages therethrough in communication with the interior of said cylinder head for conducting hot products of combustion from the engine; an electrical ignition system including a plurality of spark plugs attached to said cylinder head adjacent a longitudinal edge of said flat surface and a plurality of electrically insulated, electric current conducting cables, each of said cables having an end thereof electrically and mechanically connected to the outer terminal of a respective spark plug; a heat shield extending from said longitudinal edge of said flat surface and being spaced between said exhaust manifold and spark plug terminals and cable ends; and means for attaching said manifold to said cylinder head, said means 1allso serving to attach said heat shield to said cylinder ead.

5. In an internal combustion engine having a cylinder head provided with a substantially flat surface; an exhaust manifold mounted on said flat surface having passages therethro-ugh in communication with the interior of said cylinder head for conducting hot products of combustion from the engine; an electric ignition system including a plurality of spark plugs attached to said cylinder head adjacent a longitudinal edge of said flat surface and a plurality of electrically insulated, electric current conducting cables, each of said cables having an end thereof electrically and mechanically connected to the outer terminal of a respective spark plug; a heat shield extending from said longitudinal edge of said flat section and being spaced between said exhaust manifold and spark plug terminals and cable ends; and means for attaching said heat shield to said cylinder head.

6. In an internal combustion engine having a cylinder head provided with a substantially flat surface; an exhaust manifold mounted on said flat surface having passages therethrough in communication with the interior of said cylinder head for conducting hot products of combustion from the engine; an electrical ignition system including a plurality of spark plugs attached to said cylinder head adjacent a longitudinal edge of said flat surface and a plurality of electrically insulated, electric current conducting cables, each of said cables having an end thereof electrically and mechanically connected to the outer terminal of a respective spark plug; a heat shield spaced between said exhaust manifold and spark plug terminals and cable ends; and means for attaching said heat shield to said cylinder head.

7. For use with an internal combustion engine, an exhaust manifold gasket having a heat shield integrally formed therewith.

8. For use with an internal combustion engine, a substantially flat, generally rectangular exhaust manifold gasket section, and a heat shield integrally formed with and extending angularly from one longitudinal edge of said gasket section.

9. For use with an internal combustion engine, a substantially flat, generally rectangular exhaust manifold gasket section, and a heat shield, said heat shield comprising a body of thin-walled material integrally formed with and extending angularly from one longitudinal edge of said gasket section.

References Cited in the file of this patent UNITED STATES PATENTS 1,491,361 Reddig Apr. 22, 192.4 1,994,614 Lansing Mar. 19, 1935

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