US2635418A - Manifold mounting - Google Patents

Description

April 3 c, B. LEACH 2,635,418

MANIFOLD MOUNTING Filed Nov. 9, 1949 3nnentor (Ittornegv Patented Apr. 21, 1953 MANIFOLD MOUNTING Clayton B. Leach, Pontiac, Mich, assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application November 9, 1949, Serial No. 126,335

7 Claims.

This invention relates to exhaust manifolds for internal combustion engines and the like, and particularly to means for clamping a tubular manifold to the cylinder head or other structure containing the exhaust ports.

The invention concerns primarily, though not exclusively, an improved clamping arrangement for manifolds made of seamless or welded steel tubing. In the use of such a manifold which is generally circular in cross section, it is preferable that the side or wall of the manifold containing openings in registry with the cylinder head exhaust ports be socketed or recessed in the ported side of the cylinder head, thereby obtaining a satisfactorily tight seal around the exhaust ports without the necessity of providing a separate gasket between the manifold and cylinder head.

A problem has existed in the use of these types of manifolds in obtaining a proper clamping arrangement which will hold the manifold tightly in place under all operating conditions and which is unaffected by changes in temperature of the manifold. The use of plain strap or U-type clamps engaging the exposed portion of the manifold have been found less than satisfactory due to the fact that when the exposed portion of the tube becomes red-hot in operation it tends to collapse a certain amount under the pressure of the clamp, resulting in a subsequently loose mounting of the manifold.

' As the result of a study I have made to correct this difificulty, I discovered that the inner portion of the manifold tube in contact with the cylinder 'head remains relatively 0001 during engine operation as contrasted with the outer portion of the tube which becomes excessively hot. From this finding it was reasoned that if a clamping area could be designed which confined the clamping pressure to the inner portion of the tube, the heating up of the outer portion in operation would not affect the tightness of fit of the manifold on the cylinder head.

Accordingly, it is the prime object of my invention to provide an improved arrangement for clamping a tubular exhaust manifold to the exhaust port structure of an internal combustion engine or the like.

. A further object of my invention is to provide tubular exhaust manifold clamping means which is not subject to manifold temperature changes in operation.

A still further object of my invention is to provide an improved clamping arrangement for tubular exhaust manifolds wherein the clamping 2 pressure is applied solely to the relatively cool operating portions of the manifold.

Other objects and advantages of this invention will be apparent from the following description, having reference to the drawing wherein:

Figure l is a side elevational View of a conventional internal combustion engine incorporating my improved exhaust manifold clamping means.

Figure 2 is an enlarged sectional view of the cylinder head with the manifold in place, taken substantially on line 22 of Figure 1.

Figure 3 is a fragmentary view similar to Figure 2, showing a modified form of my clamping means.

Figure 4 is a fragmentary view in side elevation of the form of my invention shown in Figure 3.

Figure 5 is a view similar to Figure 2' but showing still another modification of my improved clamping means.

Figure 6 is a fragmentary view in side elevation showing the form of clamping means of Figure 5.

Referring now to the drawing illustrating my invention, I have shown the same applied, for example, to an overhead valve type internal combustion engine designated generally by the numeral I. As shown in Figure l, the engine includes a conventional crankcase and cylinder block structure 2 on which is a cylinder head 3 forming the usual combustion chambers (not shown) above the engine cylinders and having side openings or ports 4, 5, 6, 1, 8 and 9 leading outward from the chambers to the exhaust manifold Ill. H represents the usual cover enclosing the rockers and lubrication system for the valves located in the cylinder head '3.

As will be seen in Figure 2, the side face M of the cylinder head 3 is cylindrically recessed as at I5 to socketably receive the inner side wall portion l6 of the generally cylindrically shaped manifold In, this recess extending the full length of the cylinder head and in line with the ports 4-9. Opposite and in registry with each of these ports is an opening ll in the wall H; of the manifold through which the gases are introduced into the manifold for conduction longitudinally therethrough to an exhaust outlet pipe l8. At spaced points along the manifold l0, and preferably approximately opposite the openings H, are formed indentations 2D and 2| adjacent both sides of the recess l5. These indentations which may be formed by any suitable swaging operation on the manifold provide abutment surfaces 22 which are substantially parallel with the side face ll of the cylinder head and spaced outwardly only a short distance therefrom. The face It provides cooperating abutment surfaces for lugs 23 which serve to hold the manifold I tightly against the recess l5. These lugs in the form shown in Figure 2 are generally of L-section having legs 24 overlying the abutment surfaces 22 andjlegs. 25'at right angles thereto which engage endwise with the cylinder head face l4. Studs or bolts 26 threadedly engaging the cylinder head 3 are provided which pass through the legs 24 and serve to hold the parts in assembled relation.

As will be apparent, since; the. inner wall'pors tion [6 of the manifold I6 is in closeengagement' with the large mass of the cylinder head 3, it

will tend to remain at relatively low tempera tures during engine operation. Further, since the clamping pressure of the lugs 23 is applied as the bolts 26 are drawn up on the legs 24, the fu'lcrum'of the lever action being located at theinner ends of the legs 25.

Instead of using L-section lugs 23 as-shown in Figure 2, plain flat washers 39 may be substituted as shown in Figures 3 and 4. To provide a similar lever action by the lugs 30 a cylinder head 3 has been modified to provide inclined lug abutment surfaces 3| on each side of the recess I5. These abutment surfaces 3| incline parallel to the tubular axis of the manifold and toward the exhaust ports 4-9, the inner extremities of these surfaces being spaced a slight distance-inwardly of the cylinder head from the abutment surfaces 22 provided on the manifold. When the bolts 26 are drawn up, thelugs 30 tend to fulcrum about their outer ends 32v on thecylinder head, thereby applying an adjustable clamping pressure against the manifold surfaces 22.

In Figures and 6 I have employed the sameinclined abutment surfaces 3! on the cylinder head 3" buthave modified the lugs to provide for clamping each of them with two bolts 26 instead of one. The indentations 35 in the manifold ID are elongated longitudinally of the latter to accommodate the elongated lugs 36 as will be clear from .Figure 6.

The location of the indentations and lugs longitudinally of the manifold may be selected as desired, although it is preferable that they be placed. opposite or substantially opposite the exhaust ports. Two such arrangements shown, are in Figure l-wherein the lugs are located in oppositely. offset relation to each port, and in Figure 6 wherein thelugs v36 are located directly adjacent opposite'sides of the ports.

I claim:

1. In a multi-cylinder internal combustion engine or the like, structure forming ports for the passage of exhaust gases outwardly from the engine cylinders, an exhaust manifold for conducting the gases from the outer, ends of said ports toward one end of the. engine, said manifold being of tubular formation with one side adapted for close mating engagementwith the external surface of said structure, said side bein formed with openings in registry with said ports,

indentations formed in the surfaceofthe mam-- fold closely adjacent-said externalsurface, and

4 clamping means engaging said indentations and secured to said structure.

2. In a multi-cylinder internal combustion engine or the like, a cylinder head having exhaust ports in communication with the engine cylinders, the external surface of said head adjacent and between said ports forming a generally cylindrical recess; a tubular manifold socketed in said'recessand provided with side openings in registry with said ports, opposite walls of said manifold outwardly adjacent said recess being provided with indentations, lugs engaging said indentations, and members clamping said lugs to the cylinder'head.

3'. In an internal combustion engine or the like, structure defining a plurality of cylinder exhaustports in .spaced relation longitudinally of the engine, the external surface of said structure between and adjacent said ports being recessed to socketably receive one side of a tubular manifold, a tubular manifold socketed insaid recess and having side. wall openings in registry with said ports, seats on the external surface ofv said manifold outwardly adjacent said recess, clamping means for urging the manifold tightly against said structure including lugs withholts extending therethrough and into said-structure, saidlugs beingin abutment with said seats and structure on opposite sides only of their respectivev bolts.

4. In an internal combustion engine or the like, structure defining a plurality of cylinderexhaust ports in spaced relation longitudinally of the engine, a tubular manifold having a side wall recessed within said structure and provided with apertures in registry with. said ports, indentations-in the. periphery of the manifold forming lug abutment surfaces adjacent said structure on opposite sides ofv said. ports, lugs engaging said. abutment surfaces, and members securing the lugs-to said. structure, said structure'being provided with lug abutmentsurfaces parallel with thetubular axisof. the manifoldand incliningrecessed within said structure and provided with apertures in registry with said ports, indentations in the periphery of the manifold forming lug. abutment surfaces adjacent said structure on surfaces on said structure adjacent saidindentations, L-section lugs each having a first leg en gaging an abutment surface on said manifold.

and a secondleg engaging the adjacent abutment surface on saidstructure, and members extending through said first legs and threadedly anchoredin the structure for clamping the manifold in place.

6. In an internal combustion engineer the like, structure defining a plurality of exhaust ports in spaced apart relation along one side of the engine, a tubular manifold with one side in close mating engagement with the external surface of said structure, said last named side being provided with wall openings in registry with said ports, seats provided on the external surface of the manifold closely adjacent said last named side, and members clampingly engaging said seats and'secured to said structure.

7. In. an external manifold for connecting'a plurality ofexhaust ports-spaced along one side 5 of an engine, said manifold being tubular in section with one side Wall of the tube adapted to closely mate with the external surface of the engine surrounding said ports and provided with openings adapted to register With said ports, 5

seats provided on the external surface of the tube for engagement by clamping means secured to the engine, said seats being located on portions of the tubes external surface closely adjacent said side Wall.

CLAYTON B. LEACH.

References Cited in the file of this patent UNITED STATES PATENTS Number 10 Number Name Date Wahlberg Sept. 30, 1941 Jacobs Dec. '7, 1948 Wessman July 12, 1949 Amundson May 1, 1951 FOREIGN PATENTS Country Date Great Britain July 25, 1929

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