US 1877051 A
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Sept. 13, 1932. READ 1,877,051
INTERNAL COMBUSTION ENGINE Filed May 9, 1930 2 Sheets-Sheet l INVENTOR H BHLFOl/E EEHD B. READ Sept. 13, 1932.
INTERNAL COMBUSTION ENGINE 2 Sheets-Sheet 2 Filed May 9, 1950 INVENTOR BHLFOU/i E5 70 BY QAdV /M I A TORNEYS Patented Sept. 13, 1932 UNITED STATES BALFOUR READ, OF DETROIT, MICHIGAN INTERNAL COMBUSTION ENGINE Application filed May 9, 1930. Serial No. 450,934.
This invention relates to an improved internal combustion engine, and particularly to the cylinder head construction and valve arrangement thereof.
' The main objects of this invention are to provide overhead valves in an internal combustion engine which are suitably inclined relative to the axes of the cylinders thereof so as to allow gases to be fed to and exhausted from the cylinders through passageways communicating with the intake and exhaust manifold, respectively, which deviate but slightly from a straight source in the general dlrection of the axes of the cylinders, thus encouraging a high volumetric efliciency to provide combustion chambers in a cylinder head which are restricted somewhat for producing a turbulence in order to permit high compression of the fuel without detonation; to provide a cylinder head of this kind which is formed so as to permit the spark location of each cylinder to be positioned closer to the center of mass of the combustion chamber than in conventional overhead valve engine constructions in which the axes of the valves are parallel to the cylinder axes; to provide improved means in valve structure of this kind by which adjustment of the valve clearance may be conveniently made while the en- ;:0 gine is running; and to provide means of this kind which will also take up for wear between the valve rocker arm and its support.
Further objects of the invention are to provide a cam shaft for operating valves of the 5 above type which is located in a chamber on the cylinder block in close proximity to the cylinder head block parting line for obviating the necessity of push rods, thereby reducing the weight and number of moving parts employed and the variations in valve clearance heretofore caused by thermal expansion of long trains of valve actuating mechanism; to provide an improved valve arrangement in conjunction with which a cooling system may be used that is capable of retaining the valves and their associated parts at substantially low operating temperatures; to provide improved means for discharging a part or the whole of .the cooling medium directly upon the structure surrounding the valve and seat before the medium has been exposed to the high temperature regions of the engine; to provide compresslon resisting members in a cylinder head for receiving the compressive forces of the hold down bolts of the cylinder head so 5 as to relieve those portions of the structure in which the valve seats are formed from distortion under the action of the bolts; and to provide internal combustion engines of improved, simple and inexpensive construction.
An illustrative embodiment of my invention is shown in the accompanyingdrawings in which:
Fig. 1 is a side elevation of an internal combustion engine.
Fig. 2 is an end elevation of the engine. Fig. 3 is a plan view of the engine showing the valve casing removed to disclose the underlying structure.
Fig. 4 is a transverse vertical section of the cylinder block, cylinder head and valve mechanism, taken through the longitudinal axis of a cylinder.
Fig. 5 is a section taken on the line 55 of Fig. 4.
In the form shown, my invention is illustrated in connection with a multi-cylinder engine which includes a cylinder block 1 having a plurality of cylinders 2 therein, the axes of the cylinders being substantially ver- 30 tical. The cylinder block 1 has a cooling medium jacket 3 extending on both sides of the block, and is provided with a cam shaft housing 4: which is located. on the outer side of the right side of the jacket 3. The housing 35 4 is located at the upper end of the block 1 and has openings 5 in its upper wall which are located substantially at the top of the block. J ournaled in the housing 4 is a cam shaft 6 having cams 7 thereon. 00
The cylinder block 1 is provided with a cylinder head 8 which is seated upon a gasket 9 on the upper face of the block. The cylinder head 8 includes a combustion chamber 10 having an upper inclined wall 11 and a substantially elliptical cross section as shown by dotted lines at 12 in Fig. 3. The elliptical shape of the combustion chamber 10 causes the side 13 thereof to overhang the bore of the cylinder thereby bringing the main body of the charge closer to the s ark plug, and also producing turbulence o the charge at the end of the compression stroke owing to the restriction of the mouth of the combustion chamber and the trapping of a small portion of the charge between the under face of the cylinder head and the piston. Formed in the outer wall of the combustion chamber 10 is a threaded a erture 14 in which is mounted a spark p ug 15 having points 161 which are located close to the center of volume of the charge.
Each combustion chamber of the engine has a pair of communicating gas passages .16, one for admitting fuel into the combustion chamber, and the other for exhausting the products of combustion therefrom. These passageways lead into apertures in the inclined wall 11 of the combustion chamber and have an arcuate curvature at their inner end and a reverse curvature at their outer end. The curvature of the passages 16 is but slight and in general their courses are inclined somewhat to the left as viewed in Fig. 4 but the inclination is limited and portions of the passages are in alignment, from end to end, with the length of the cylinder. This construction provides direct and unobstructed paths for incoming and outgoing gases.
Formed at the junctions of the passages 16 and the combustion chamber 10 are valve seats 17 and 18.
Formed in the cylinder head 8 in related proximity to each combustion chamber 10 thereof are a pair of valve stem supports 19 and 20 in which the, valve stem guides 21 and 22 are provided. Slidably mounted in the guides 21 and 22 are valve stems 23 and 24 respectively, having valves 25 and 26 on their inner ends which are adapted to be received by the valve seats 17 and 18 respectively. The valve stems 23 and 24 extend outwardly of the head and are provided at their outer end portions with springs 27 which may bear against flanges 128 on the guides 21 and 22 at one end and against collars 29 on the stems 23 and 24, at their other end. These springs normally tend to retain the valves 25 and 26 in a closed position.
The intermediate portion of the cylinder head 8 includes a cooling medium jacket 30' having a passage 31 therethrough which communicates with passages 32 extending between adjacent valve stem supports 19 and 20 and communicating with a passage 33 which extends substantially around the supports.
The cooling medium jacket 31 extends longitudinally of the head 8 and the passage 31 thereof communicates with a passage 34 on the left side ofthe cylinder head as viewed in Fig. 4. A cooling medium inlet pipe 35 extends longitudinally through the passage 31 and has a branch 36 which communicates with a pump 31' which circulates the cooling medium in the direction of the arrow shown in Fig. 3. The inlet pipe 35 has a plurality of discharge openingz 37 each in registration with a passage 32 tween the valve stem supports 19 and 20. These discharge openings direct the incoming cooling medium into the passages 32 and circulate the same around the supports 19 and 20 and through the passage 33. In this manner, the cooling medium is directed upon that structure of the cylinder head in which the valve seats and valve parts are located before the cooling medium has been exposed to the regions of the engines of high temperatures, thereby protecting the valves, valve seats and their associating parts from excessively high temperatures and consequent warpage or distortion.
Extending vertically through the passage 31 of the water jacket 30 are cylindrical posts tappet rod 41 and valve stems 23 and 124 are substantially parallel to each other and they are inclined with respect to the axis of the cylinder 2 at a suitable angle, so as to permit the formation of the above described gas passages 16 in the cylinder head 8. It has been found that the inclination of the valve stems and the supports in which they are slidably mounted, may vary only within definite limits without introducing certain disadvantages or preventing other advantageous constructions from being included in the present invention. If the inclination of the valve stems is less than 25 to the axis of the cylinders it is necessary to incline the gas passages 16 further to the left than is shown in Fig. 4, resulting in the formation of a less direct path for the incoming and outgoing gases, and which moreover interferes with the disposition of the spark plug and cylinder bolts. If the valve'stems are inclined with respect to the axis of the cylinder at an angle greater than 35 degrees, the width of the c linder head is by a cross bar 45 in which apertures 46. are I formed. Threaded in each aperture 46 is an adjustable bolt 47 having a substantially semi-spherical lower end 48. A rocker arm 49 having a recess 50 at its intermediate portion in which the semi-spherical head 48 is 5 seated, bears at its ends upon the outer extremity of the valve stem 23 as shown in Fig. 4 and the tappet rods 42, each valve stem 23 and 24 being provided with a rocker arm 49 of the form shown in Fig. 4.
The rocker arm 49 must be prevented from turning and getting out of line with the valve stems 23 and 24 and tappet 42, and one method of doing this is by means of a U-shaped clip 51 mounted on the right end of-the arm and having side portions which extend downwardly and engage the sides of the ta pet rods. The inner end of the tappet r 42 extends into the cam shaft housing 4 throu h the aperture 5 therein and rests upon t e cam 7 ofthe cam shaft. The cam shaft 6 and cam 7 act directly upon the inner end of the tappet rod 42, thus obviating the necessity of push rods and long train of valve actuatin mechanisms which are subjected to consi erable thermal expansions and cause the valve clearance to be varied during heating of the engine. The overhead valve mechanism is inclosed within a casin 52 removably mounted on the head 8 by bolts 53 and nuts 54. Lubricant may be be suitably fed to the various wearing surfaces within the casing 52 which prevents its subse uent escape, a portion of such lubricant fin ing its way into the recesses 50 of the rocker arms 49 where it provides a bath of lubricant for the wearing surfaces therein.
The adjustment bolts or pivots 47 may be conveniently adjusted while the engine is running and they may be set in an adjusted posi- 40 tion by lock nuts 55 so as to predetermine the valve clearance. Adjustment of the bolts 47 may also be relied upon to take up for wear between the moving parts of the valve actuating mechanism.
Although but one specific embodiment of this invention has been herein'shown and described, it will be understood that numerous details of the construction shown ma be altered or omitted without de arting mm 50 the spirit of this invention as efined by the followin claims.
What claim is: 1. In an internal combustion engine, a block having a c linder therein, and a water jack- 55 eted cylin er head on said block having a combustion chamber and a communicating passage, the respectively opposite end portions of said passage having substantially arcuate curves of reverse curvature and por- 60 tions of said passage being in alignment from end to end with the length of said cylinder. 2. In an internal combustion engine, a block having a cylinder therein, a cylinder head on said block including a combustion chamber and a communicating passage havmounted in said cylinder head and extending at an inclination toward the opposite lateral side thereof. I
3. In an internal combustion engine, a block having a cylinder therein, a c linder head on said block including a com ustion chamber and a communicating assage having oppositely reversely curve u per and lower arcuate sections and exten ing in a course generally inclined toward one lateral side of said cylinder head, portions of said passage being in alignment from end to end with said combustion chamber, a valve at the junction of said passage and combustion chamber having a stem slidably mounted in said cylinder head and extending at an inclination toward the opposite lateral side thereof, a tap et carried by and slidably mounted in sai cylinder head extending substantially parallel. to said valve stem, and means mounted on said cylinder head for transmitting movement from said tappet to said valve.
4. In an internal combustion engine, a block havin a cylinder therein, a cylinder head on sald block having a combustion chamber and a communicating passage extending from the roof of said chamber to the top of said cylinder head at an inclination toward one side wall thereof and having successively adjacent portions in alignment from end to end with said combustion chamber, a' valve at the junction of said passage and said combustion chamber 3 ving a stem slidably mounted in said cylinder head and extending toward the opposite lateral side thereof, a tappet slidably mounted in and carried solely by said cylinder head extending substantially parallel to said valve stem, said passage, valve stem and tap et being confined wholly within the lateral sides of said cylinder head and substantially aligned transversely of the latter, and means mounted on said cylinder head for transmitting movement from said tappet to said valve.
' BALFOUR READ.