US2281694A - Manifold - Google Patents

Description

Patented May 5, 1942 MANIFOLD John S. Huber, South Milwaukee, Wis.,assignor tov Nash-Kelvinator Corporation, Wis., a corporation of Maryland Kenosha,

Application June 5, 1940, Serial No. 338,845

(Cl. Eli-52) 21 Claims.

This invention relates to manifolds and has particular reference to intake manifolds for internal combustion engines.

It is an object of this invention to provide a novel manifold which will provide a more smoothly operating engine.

It is another object of this invention to provide a novel manifold which will cause an engine to operate more economically.

It is another object of this invention to provide a manifold which will give a more even distribution of fuel to the various cylinders of an internal combustion engine.

It is another object of this invention to provide novel means for equally distributing the fuel in a manifold to several cylinders;

Other objects and advantagesof this invention will be apparent from aconsideration of the following' description and claims and the attached drawings of which there is one sheet and in which- Figure 1 represents an end elevation of the upper portion of an internal combustion engine;

Figure 2 represents a section. taken along a plane indicated by the line 2-4 in Figure 1 and looking in the direction of the arrows;

Figure 3 represents a section taken along a plane indicated by the line 3--3 in Figure 2 and looking in the direction of the arrows;

Figure 4 represents a section taken along a plane indicated by the line 4-4 in Figure 2 and looking in the direction of the arrows;

Figure 5 is a view similar to Figure 3 but illustrating a modified type of construction; and,

Figure 6 represents a view similar to Figure 4 but showing a modified type of construction.

In practically all internal combustion engines which use a carburetor to mix the engine fuel (usually gasoline) with air before delivering the fuel to a manifold for distribution to the several cylinders, it is practically impossible to obtain perfect carburetion. The fuel will not all be vaporized, and there will be a considerable amount of fuel in the form of large particles known as heavy fuel" carried along with the mixture of air and true fuel vapor. This heavy fuel tends to precipitate out of the rest of the fuel vapor and air mixture, and in engines having a long horizontal manifold, it collects as a liquid on the floor of the manifold. Naturally, more liquid will collect near the carburetor while relatively little heavy fuel will reachthe end or ends of the manifold ,away from the carburetor.

As the intake valves of the various cylinders open", there is, a rush ofair and fuel vapor out of the manifold into the corresponding intake port. This rush of air and vapor will pick up or draw a considerable quantity of the heavy fue off the floor of the carburetor into the cylinder which is being charged. Naturally, the cylinders near the carburetor will draw in more of the heavy fuel because more is present near their intake port. This unequal fuel distribution leads to unequal power development in the various cylinders and rough uneconomical operation of the engine as a whole.

I have devised means for overcoming the above difficulties which consist generally of a baffle which will distribute the heavy fuel more equally throughout the manifold and another baffle which will adjust the size ofthe several intake ports so that the velocity of the'air-and fuel through the several ports will be such as to draw equal quantities of heavy fuel over the first baiile. The velocity of the air at each cylinder will be approximately equal with slight increases at the ports where it is necessary to draw the heavy fuel over a higher portion of the first baifle.

In the drawing, the invention is illustrated as being applied to an engine having a manifold cast in the block of the engine but the invention is equally effective when used on other types of engines.

The engine consists of a cylinder block 10 having an overhanging portion 12 within which are formed the intake manifold M and exhaust ports IS. The exhaust ports l6 connect to the exhaust pipe l8 secured to the side of the overhanging portion l2 by the clamps and bolts 22 (see Figure 1). The overhanging portion i2 is provided with cooling water space 13 (Figure 2) under the manifold M and around the exhaust ports l6.

Positioned on top of the cylinder'block i0 is a head casting 24 which forms a head for the cylinders and a cover for the manifold M. The head 24 carries the spark plugs 26 and the car buretor 28 which communicates with the manifold I4 through the port 30 (see Figure 2). The

head 24 is secured to the cylinder block by the usual head bolts 32. Cooling water space 34 is provided in the head 24 in the usual manner, and ribs 35 are provided in the cooling water space to strengthen the head and direct the water flow. A head gasket 31 is provided between the head and the cylinder block.

Intake manifold M is generally rectangular in cross section and extends longitudinally along the block l0. The manifold 14 is symmetrical- Secured to the fioor 46 of the manifold I 4 by screws 48 is a plate 50 which is bent up to form a generally vertical flange 52. Flange 52 is highest at its end near the center of the engine and tapers down to a very low height in front of the end port 38. It will be noted that the plate 50 and flange 52 are carried only part way across the port 38 so at least part of the port 38 is unobstructed (see Figure 2). The flange 52 is positioned adjacent the inner wall of the manifold I4 in which the ports 36 and 38 are formed.

The flange 52 masks or obstructs the ports and 38 without materially obstructing the manifold I4. Port 35 is obstructed more than port 38 because of the increased height of the flange 52 in front of port 35. The flange 52 will prevent some of the heavy fuel which collects on the floor ofthe manifold from being drawn into port 36. The heavy fuel thus excluded from the port 36 will be carried toward the end of the manifold and will be drawn into port 38 which is not obstructed as much as port 36. In this manner an even distribution of the heavy fuel along the length of the manifold is obtained.

Since all cylinders will suck in an equal volume of air and fuel vapor and since the port 36 is more obstructed by bafiie 52 than is port 38, the velocity of the air and fuel vapor passing into port 36 would be greater than the velocity. into port 38. The amount of heavy fuel picked up by the air and fuel vapor is proportional to the velocity of the air and vapor, and the increased velocity through port 36 would tend to counteract the distributing effect of the baffle 52. To neutralize the velocity increasing effect of the baffle 52 at port 36, the head 24 has secured thereto a Wedge-shaped block 54. Block 54 is held in place by a screw 56 and is located so as to fit within the manifold I4 when the head 24 is in place on the block I0. Wedge 54 is almost as wide as the manifold I4, only enough space being left along its side to allow it to be easily fitted into the manifold when the head is put in place. The wedge tapers from a thin section near the center of the manifold to a thick section at the end in front of the port 38.

The wedge 54 cuts down the effective cross sectional area of the manifold I4 toward its end so that the velocity of air and fuel vapor is increased near the end of the manifold and through port 38. This increased velocity causes an increased amount of the heavyfuel to be carried along the manifold into the end cylinder, thus neutralizing the effect of the bafile 52 in increasing the velocity through the port 36 as explained above and further aiding the end port 38 in obtaining a supply of liquid fuel.

The net result of placing the baffle 52 and wedge 54 in the manifold I4 is to bias the flow of heavy fuel toward the end of the manifold so that equal amounts are available adjacent the ports 36 and 38, and to adjust the velocity of the air and fuel vapor mixture-entering the ports 36 and 38 so that equal ,proportio ns of heavy fuel.

are drawn into each of the ports with fuel and air mixture. Either the bafiies 52 or wedge 54 alone will tend to equalize the amount of heavy fuel drawn into the cylinders, but the combination of the wedge and bafile allows a more perfect balance to be reached.

It is to be understood that only one half of the motor is shown in the drawing and that the baffle and wedge just described are duplicated on the other half of the engine on the opposite side of the carburetor port 30 and that the system will be equally effective with other arrangements of intake ports, whether or not the ports are arranged symmetrically with respect to the carburetor port.

In Figures 5 and 6 the floor I46 of the intake manifold H4 is shown to be cast with a tilted or raised side I52 which takes the place of the baffle 52 in Figures 2 to 4. The raised side I52 is highest opposite the central port I36 and slopes downwardly toward the end' port I38 until the floor I46 is flat at the end of the manifold. The floor I46 slopes transversely from the raised edge I52 to the outside edge of the manifold.

The wedge I54 is cast integrally with the head I24 and is the same shape as the Wedge 54 in Figures 2 to 4. Wedge I 54 functions in the same manner as wedge 54 and does away with the screws 56. Cooling water space I34 is extended into a pocket I37 in the wedge I54 to increase the amount of heat added to the fuel mixture.- Otherwise the cylinder block H6 and head I24 are the same as the block I0 and head 24 shown in Figures 2 to 4.

The invention may be used effectively in connection with motors having separate external manifolds, and the modification shown in Figures 5 and 6 may be employed in manifolds that are cast as a closed passage Without a cover by casting the wedge I54 along with the top wall of the manifold.

While I have described my invention in some detail, I intend this description to be an example only and not limiting of my invention to which I make the following claims.

I claim:

1. In a manifold having a plurality of ports opening from the side thereof, a carburetor passage formed in said manifold, a member positioned in said manifold to increasingly reduce the cross sectional area of said manifold towards the ends thereof, and means partially obstructing the port nearest the carburetor passage.

2. In a manifold having a plurality of ports opening from the" sidethereof, a cover for said manifold, a carburetor cover, a projection formed on said cover and extending into said manifold to increasingly reduce the cross sectional area of the manifold towards the end thereof, and means partially obstructing the lower portion of the port nearest the car buretor passage.

3. In a manifold having a plurality of ports opening from the side thereof, a carburetor passage formed in said manifold, and means partially obstructing the lower portion of said ports, said means obstructing each successive port to a less extent, the port nearest the carburetor passage being obstructed the most.

4. In a manifold, means for introducing 'fuel and air into said manifold, a plurality of ports: opening from said manifold, said ports being with respect to said fuel.

located symmetrically introducing means, and means obstructing the flow of heavy .fuel into said ports, said obstruct-= passage formed in said ing means decreasing as they are extended away from said fuel introducing means.

5. In a manifold having ports opening from the side thereof, a wedge shaped member positioned in said manifold to increasingly reduce the cross sectional area of said manifold toward the end thereof, said ports opening into said manifold below said Wedge member.

6. In a manifold having ports opening from the side thereof, a cover for said manifold, and a wedge shaped member on said cover extending into said manifold, said wedge shaped member reducing the effective cross sectional area of said manifold toward the end thereof.

7. In combination with an internal combustion engine, a manifold for said engine defining a plurality of ports, said manifold having a roof sloping downwardly toward the ends thereof and having a generally horizontal floor.

8. In a manifold having ports opening from the side thereof, bame means partially obstructing said ports in decreasing amounts toward the end of said manifold, and a wedge shaped member positioned in said manifold and decreasing the effective cross sectional area toward the end thereof.

9. In a manifold having ports opening from the side thereof, baffle means partially obstructing said ports in decreasing amount toward the end of said manifold, and a wedge shaped member positioned in said manifold and decreasing the effective cross sectional area toward the end thereof, said wedge shaped member being secured to the top wall of said manifold.

10. In a manifold having ports opening from the side thereof, a plate secured to the floor of said manifold, a triangular flange bent up from said plate adjacent said ports, said triangular flange having its apex near the end of said manifold, and a wedge shaped block secured to the top of said manifold, said wedge shaped block having its thickest portion at the end of said manifold.

11. In a manifold having ports opening from the side thereof, a plate secured to the floor of said manifold, a triangular flange bent up from said plate in front of said ports, said triangular flange having its apex near the end of said manifold, and a wedge shaped member depending from said cover into said manifold, said wedge shaped member being thickest near the end of said manifold.

12. In a manifold having ports opening from the side thereof, a plate secured to the floor of said manifold, a triangular flange bent up from said plate in front of said ports, said triangular flange having its apex near the end of said manifold, and a wedge shaped member depending from said cover into said manifold, said wedge shaped member being thickest near the end of said manifold, said plate and triangular flange terminating before being carried completely across the front of the end port.

13. In a manifold having ports opening from the side thereof, a plate secured to the floor of said manifold, a triangular flange bent up from said plate in front of said ports, said triangular flange having its apex near the end of said manifold, and a wedge shaped member depending from said cover into said manifold, said wedge shaped member being thickest near the end of said manifold, said cover for said manifold being a part of a head casting.

14. In a cylinder block, a manifold cast along the top of said block, a wall of said manifold defining a series of ports, the floor of said manifold sloping downwardly from points near the longitudinal center and inside edge of said manifold to the ends and outside edge of said manifold.

15. In a cylinder block, a manifold cast along the top of said block, a wall of said manifold defining a plurality of ports arranged symmetrically about the center of said manifold, the floor of said manifold having a straight outside edge and ends and an inside edge curving from a high point at the center of said manifold to the ends of said manifold.

16. In a cylinder block, a manifold cast along the top of said block, a, wall of said manifold defining a plurality of ports arranged symmetrically about the center of said manifold, the floor of said manifold having a straight outside edge and ends and an inside edge curving from a high point at the center of said manifold to the ends of said manifold so as to partially obstruct the ports toward the center of said manifold.

17. In combination with a cylinder block having a, manifold extending along the top thereof, a head for said block defining a carburetor passage arranged to fit over the middle of said manifold, projections formed on the underside of said head on each side of said passage and arranged to fit into said manifold, said projections increasing in cross sectional area as they approach the ends of said manifold.

18. In combination with a cylinder block having a manifold extending along the top thereof, a head for said block defining a carburetor passage arranged to fit over the middle of said manifold, projections formed on the underside of said head on each side of said passage and arranged to fit into said manifold, said projections increasing in cross sectional area as they approach the ends of said manifold, and cooling water pockets formed in said projections.

19. A manifold having a carburetor passage in the center thereof, ports formed symmetrically in the side of said manifold with respect to said passage, the ports nearer said passage being located at a higher level than those toward the ends of said manifold, and a floor for said manifold having a straight outer edge.

20. A manifold having a carburetor passage in the center thereof, ports formed symmetrically in the side of said manifold with respect to said passage, the ports nearer said passage being located at a higher level than those toward the ends of said manifold, and a floor for said manifold having a, straight outer edge, said manifold having a cross sectional area decreasing in size toward its ends.

21. In combination with a cylinder block having a manifold extending along the top thereof, a head for said block defining a carburetor passage arranged to fit over the middle of said manifold, and projections formed on the underside of said head on each side of said passage and arranged to fit into said manifold, said projections having cooling water pockets formed therein.

JOHN S. HUBER.

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