US2691366A

US2691366A - Air-cooled cylinder head for internal-combustion engines

Info

Publication number: US2691366A
Application number: US249243A
Authority: US
Inventors: Flatz Emil; Hovel Josef
Original assignee: Kloeckner Humboldt Deutz AG
Current assignee: Kloeckner Humboldt Deutz AG
Priority date: 1950-10-28
Filing date: 1951-10-02
Publication date: 1954-10-12
Anticipated expiration: 1971-10-12

Description

Oct. l2, 1954 E FLA-rz ET AL 2,691,366

-COMBUSTION ENGINES AIR-COOLED CYLINDER HEAD FOR INTERNAL 2 shets-sheet 1 Filed Oct. 2. 1951 .ZY/[Maes Hafl- Jose/f H'vel Raw; 47M? llil.

Oct. 12, 1954 E. FLATz ETAL 2,691,366

DER HEAD FOR INTERNAL-COMBUSTION ENGINES AIR-COOLED CYLIN 2 Sheets-Sheet 2 Filed Oct. 2 1951 Patented Oct. 12, 1954 AIR-COOLED CYLINDER HEAD FOR INTERNAL-CGMBUSTION ENGINES Emil Flatz, Bergisch-Gladbach, and Josef Hvel,

Koln-Bruck, Germany,

Humboldt-Deutz Aktien many assignors to Klcknergesellschaft, Koln, Ger- Application October 2, 1951, Serial No. 249,243

Claims priority, application Germany October 28, 1950 6 Claims. (Cl. 12S-411.69)

The present invention relates to internal combustion engines and, more particularly, to air cooled cylinder heads for internal combustion engines.

While not specifically limited to, the present invention is of particular advantage for such cylinder heads of. internal combustion engines which are provided with two passages of the inlet and/or outlet of a gaseous medium, one of said passages leading upwardly, While valves .are arranged, one behind the other, when looking in the longitudinal direction of the engine, and While above the cylinder head, there is arranged a cup for receiving the rocker arms for actuating said valves.

As is well known, with an air cooled cylinder head for internal combustion engines, the cooling of that area which is located between the valves presents considerable difculties. rThis is due to the fact that it is rather difficult to bring e from the outside suciently large quantities of cooling air to the said area. The passages extending from said valves impede the now of cooling air considerably. In order to obtain more favorable conditions for the passage of cooling air, it has been attempted to run the pasasge in diierent directions toward the outside. Thus, it has been suggested to run the outlet passage toward the side, and to run the inlet passage toward the top through the cup on top of thc cylinder head which cup for actuating the valves. Such an arrangement, however, has not proved successful for reasons which will subsequently appear.

The passing of the inlet passage through the cup makes it necessary for reasons connected with the casting operation proper, to place the cup as separate piece upon the cylinder head. Tests with air cooled cylinder heads having mounted thereon a separate cup for receiving the rocker arms have proved that it is extremely dihicult, if not impossible, for any practical length of time to connect such cup in an oil leak-proof manner with the cylinder head. It cannot be prevented that after a relatively short receives the rocker arms time, the oil intended and necessary for the lubrication of the rocker arms seeps through downwardly and wets the cylinder head. As a direct result thereof, the heat transfer from the cylinder head to the cooling air will be decreased. Furthermore, the impurities present in the cooling air remain stuck atthe oil wetted portions of the cylinder head andgradually build up a thick insulating layer preventing a proper heat exchange.

v with the cylinder head, thereby preventing any lubricating oil from passing through the cup toward the cylinder head.

It is still another object oi this invention, to provide an air cooled cylinder head of the type mentioned above, which will materially increase the cross section for the passage of the coolingr air between the valves.

It is also an object of this invention to provide an air cooled cylinder head for use in connection with internal combustion engines, in which a passage extending from one of its valves toward the top of the cylinder head is arranged so that it can easily be cast together with the cylinder head while oiering only a minimum of resistance to the medium passing through said passage.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection With the accompanying drawings in which:

Fig. l represents a vertical section through a cylinder head according tothe present invention, the section being taken along the vertical plane passing through the valves.

Fig. 2 is a transverse section along the line II-II of Fig. 1.

Fig. 3 is a top view of the cylinder head of Fig. 1.

Fig. 4. is a transverse section similar to that of `Fig. 2 but slightly modined with regard to the latter.

Fig. 5 is a transverse section through still another modified cylinder head according to the present invention.

General arrangement As mentioned above, the present invention concerns an air cooled cylinder head with two passages for the inlet and/or outlet of a gaseous medium, which passages are controlled by valves arranged one behind the other, when looking in longitudinal direction of the engine, while on top of the cylinder head there is provided a cup for receiving the rocker arms adapted to actuate the valves. According to the present invention, one of the said passages extends from one of the valves to the top` of the cylinder head in such a manner that its mouth at the top of the cylinder head is located outside the cup.

According to a preferred embodiment of the invention, the passage leading to the top of the cylinder head of one cylinder of a multi-cylinder engine is so arranged that its upper portion lies over a portion of the adjacent cylinder head. In order that in such an arrangement the cylinder heads may be uniformly constructed and the cylinders be arranged as close together as possible, that cooling iin portion of one cylinder head which is adjacent to the upper portion of the upwardly leading passage of the adjacent cylinder head, is provided with a recess or cut-out or is reduced in height.

In view of the arrangement of the upwardly leading passage in the manner just mentioned, it is possible to cast the cup with the cylinder head as one integral piece.

In order further to improve cylinder head when the latter is to be used in connection with an internal combustion engine having a cam shaft in the crank case and push rods between the cam shaft and the rocker arms,

the second passage in the cylinder head is so arranged that its mouth is located on the longitudinal side of the engine, while the push rods are arranged on each side of said mouth respectively.

According to a modification oi the arrangement set forth in the preceding paragraph, the mouth of the second passage may be located on the longitudinal side cf the engine but laterally of the central cylinder head plane which is substantially transverse while both push rods are located on one and the same side of said last mentioned mouth. In this instance, the push rods are preferably located symmetrically to the central transverse plane of the cylinder head.

While in most instances the passage leading upwardly to the top of the cylinder head serves as inlet passage, it is to be understood that the upwardly leading passage may also serve as outlet passage.

As is well known, there are two stroke cycle engines having a cylinder head with two valves for controlling the discharge. Thus, with this type of internal combustion engines, the two passages arranged in the cylinder head are discharge passages. It is obvious that with such two stroke cycle engines, the cooling of that area ci the cylinder head which is located between the discharge valves is even more diicult so that the present invention is of particular importance for this type of two stroke cycle internal combustion engines.

Structural arrangement Referring now to the drawings in detail and Figures 1 to 3 thereof in particular, the structure shown therein comprises a cylinder head i provided with a discharge valve 2 and an intake valve 3. From the discharge valve 2 there extends a discharge passage Il leading to the outside of the cylinder head and having its mouth located on the longitudinal side of the engine to which the cylinder head pertains. Another passage 5, in this particular instance an intake passage, extends from the intake valve 3 likewise to the outside of the cylinder head l but has its mouth on the top side of the cylinder head. As will be seen from Fig. l, the upper end portion of the ypassage 5 is located laterally of the cup 6 which latter has been cast as an integral piece with the cylinder head. The cup 6 serves the cooling of the to said longitudinal side, i;

4 for receiving the rocker arms l' (Fig. 3) intended for actuating the valves 2 and 3. In addition to the valves 2 and 3 and the passa-gesl! and 5, the cylinder head also comprises a main combustion chamber s connected by a throat with a combustion chamber 9.

As will be clear, particularly from Figures 1 and 2, the new arrangement of the intake passage creates between the two valves 2 and 3 a materially increased cross section for the passage o cooling air. Therefore, the invention makes it possible above the web I0, which is 1ocated between valves 2 and 3, to provide a greater number of cooling iins Il than heretofore possible, which fins will receive the heat from the web IB and transfer the thus received heat to the cooling air which carries it away.

In order to avoid that due to the new arrangement of the passage 5, particularly the upper end thereof, the distance between two adjacent cylinders has to be enlarged, the upper end of the passage 5 is so arranged that it lies over a portion of the adjacent cylinder head i2, while the cooling iins of the latter are correspondingly recessed or shortened so as not to interfere with the passage 5. For the sake of simplicity and uniformity, preferably all cylinders of the internal combustion engine have their corresponding cooling fins similarly recessed or shortened.

With the cylinder head according to Figures l to 3, the orifice of the discharge passage d is located in the central vertical transverse plane of the cylinder head l. This makes it possible respectively to arrange the push rods i5 at both sides of the passage fi and symmetrically with regard to the said central vertical transverse plane of the cylinder head. The push rods I5 are actuated in the usual manner by a cam shaft located in the crank case of the engine (not hshown in the drawings). v

According to the modiiications shown in Figures a and 5, a further improvement of the cooling effect of the air passing between the valves 2 and 3, and also a simpler construction of the cooling fins l l between the valves can lne-obtained when the orice of the passage t is located laterally of the above mentioned vertical central transverse plane of the cylinder head. In such an instance, a straight passage for the cooling air is obtained, and the cooling fins can be made straight.

According to Fig. 4, the discharge passage t is bent oif toward one side to such an extent that its orifice is located outside the symmetrically arranged push rods lli. One of the connecting screws It of the cylinder head is located inside the discharge passage.

According to Figure 5, the discharge passage i is passed by the connecting screw il'. The push rods l5, however, are again arranged at both sides of the discharge passage l but like the latter are located laterally of the above mentioned central vertical transverse plane.

It is, of course, understood that the present invention is, by no means, limited to the particular constructions shown in the drawings but aiso comprises any modifications within the scope ci the appended claims.

What we claim is:

l. An air cooled cylinder head arrangement for a multi-cylinder internal combustion engine, which comprises in combination, a nrst cylinder head, a second cylinder head in line with said first cylinder head, cooling Iins respectively connected to the outside of said cylinder heads, each of said cylinder heads having arranged therein rst valve passages means adapted to be controlled by a Valve, and also second valve passage means adapted to be controlled by another valve, rst cup means arranged on top of said rst cylinder head and integral therewith, second cup means arranged on top of said second cylinder head and integral therewith, each of said cup means being adapted to receive valve actuating rocker arms, and channel means respectively arranged in each of said cylinder heads and extending from one of said valve passage means to the top of the respective cylinder head and outside and laterally of the adjacent cup means, the upper end portion of the channel means pertaining to said rst cylinder head extending over a portion of said second cylinder head.

2. An air cooled cylinder head arrangement fora multi-cylinder internal combustion engine,

'which comprises in combination, a rst cylinder head, a second cylinder head in line with said rst cylinder head, cooling ns respectively connected to the outside of said cylinder heads, each of said cylinder heads having arranged therein rst valve passage means adapted to be controlled by a valve, and also second valve passage means adapted to be controlled by another valve, first cup means arranged on top of said `iirst cylinder head, second cup means arranged on top of said second cylinder head, each of said cup means being adapted to receive valve actuating rocker arms, and channel means respectively arranged in each of said cylinder heads and extending from one of said valve passage means to the top of the respective cylinder head and outside the adjacent cup means, the upper end portion of the channel means pertaining to said rst cylinder head protruding beyond a portion of said second cylinder head, and those iins of said second cylinder head which are adjacent said last mentioned upper end portion being of such size and shape as not to interfere with said last mentioned upper end portion.

3. In combination for use in connection with an internal combustion engine, a cylinder head, cooling ns connected to the outside of said cylinder head, an intake passage arranged Within said cylinder head and adapted to be controlled by an intake valve, an exhaust passage arranged within said cylinder head and adapted to be controlled by an exhaust valve, cup means integral with the top of said cylinder head for receiving y valve actuating rocker arms, inlet channel means extending from said intake Valve passage to and having its mouth located in the top surface of said cylinder head and outside said cup means, and exhaust channel means extending from said exhaust passage to and having its mouth protrude beyond one of those sides of said cylinder head which form the longitudinal sides of the engine, the axis of the outer end of said exhaust passage being located laterally of the vertical central plane passing through the cylinder head and being substantially perpendicular to the longitudinal direction of the engine, and additional cooling fins between said inlet and said outlet channel means and integral with said cylinder head.

4. In combination in a cylinder head arrangement for use in connection with an internal combustion engine, a cylinder head, cooling ns connected to the outside of said cylinder head, a first valve passage arranged Within said cylinder head and adapted to be controlled by a rst valve, a second valve passage ararnged Within said cylinder head and adapted to be controlled by a second valve, cup means integral with the topk of said cylinder head for receiving valve actuating rocker arms, first channel means extending from said rst valve passage to the top surface of said cylin` der head and having its mouth located in said top surface and outside said cup means, second channel means extending from said second valve passage to and having its mouth protruding beyond one of those sides of said cylinder head which form the longitudinal sides of the engine, push rods arranged at both sides of the outer end of said second channel means for actuating said rocker arms, and additional cooling fins extending between said push rods.

5. In combination in a cylinder head arrangement for use in connection with an internal comhead outside said cup means, second channel` means extending from said second valve passage to one of those sides of said cylinder head which form the longitudinal sides of the engine, and a pair of push rods arranged at one and the same side of the outer end 'of said second channel means for actuating said rocker arms.

6. In combination for use in connection with an internal combustion engine, a cylinder head, cooling ns connected tothe outside of said cylinder head, an intake passage arranged within said cylinder head and adapted to be controlled by an intake valve, an exhaust passage arranged within said cylinder head and adapted to be controlled by an exhaust valve, cup means integral with the top of said cylinder head for receiving valve actuating rocker arms, inlet channel means extending from said intake valve passage to the top of said cylinder head outside said cup means, and exhaust channel means extending from said exhaust passage to one of those sides of said cylinder head which form the longitudinal sides of the engine, the axis of the outer end of said exhaust passage being laterally spaced from that vertical central plane, Which passes through the cylinder head and is substantially perpendicular to the longitudinal direction of the engine, and a first and second push rod for actuating said rocker arms, said nrst push rod being arranged between said vertical plane and the outlet of said exhaust channel means, and both of said push rods being arranged symmetrically with regard to said vertical central plane.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,506,950 Smith Sept. 2, 1924 1,884,321 Smith Oct. 25, 1932 2,199,619 Daub May 7, 1940 FOREIGN PATENTS Number Country Date 346,683 Germany Jan. 6, 1922 900,899 France Oct. 23, 1944 574,684 Great Britain Jan. 16, 1946