US2186259A - Internal combustion engine - Google Patents

Description

1940- J. R. M NEIL 2,186,259

INTERNAL COMBUSTION ENGINE Filed Dec. 16, 1938 2 Sheets-Sheet 1 %zlsATToRNEYs Jan. 9, 1940. J. R; MCNEIL 2,186,259

INTERNAL COMBUSTION ENGINE Filed Dec 16, 1938 2 Sheets-Sheet 2 4z'6ATroRNEYs so adapted to' drive connecting rods H) which are Patented Ja 9, 1940' OFFIC invention: r elates to-internal combustion engines.- l

An object" of my invention ,is to provide an internalcombnstion engine of the overhead valve type-whichis simplefinconstructionand-quiet in operation.

Another object of my invention is topro-vide an internal combustionengine of the overhead valve type 'W'herein the push rods and rocker a simplified way-ofreplacing the chain for driv- 1' ing the cam shaft from which the intake and armsnorm'ally employed for actuating the intake and exhaust valves, are eliminated. e

A further object of my inventionis to'provide exhaust valves are actuated.

. q 7 Other objects and advantages of my invention will be apparent from the followingI'description;

' sprocket. I g The internal combustion engine'of my inventio'n' isof the-overhead valve typeand comprises when taken in'connection'withthe accompanying drawings in which f Fig. 1. is a sectional view taken thr'oughthe e of cranks 4| which] are adapted to' actuate connecting rods {32, which extend upward from the crank shaft through an opening formed" in the internal combustion engine ofmy invention;

' r Fig. 2'is a sectional view, taken substantially on theqline 2*2 of Fig. l, in-the direction indicated .by-thearrows; J

I Fig. 3 is a view taken on the line 3 -3 of 1 inthe direction indicated by the arrows; I

Fig.14is a View showing the connecting 'rodassembly'fo-r drivingthe' jack shaft;-

Fig. 5; is a sectional view showing the method.-

of mountingthe chain sprocket on the cam shaft; Fig. 6 is a iew taken on' theiline 8 ii of Fig. 3 in the direction indicated bythe arrows; and Fig. '7 is a view showing the castingfor sup porting of the cam shaft and the driven chain the usual cylinder block lljlcr-ank casef I2'Ia'nd cylinder head i3. The crankcase l2fhasi'the" usualcrank-case pan I iwand. has mounted in suitable bearings 15 a crank shaft H. The crank shaft has the: conventional "cranks l 8 for actuat fl ing'the pistons as the crank .shaft is rotated.

' -Whilel"I-have shown-[only four cylinders of my novel internal combustion engine, itwill: be un derstood that two additional, cylinders (not shown) are provided. Moreover, it will be: apparent that the invention may be also applied 7 1:02.11 engine having four, eight or any other dey The cranks {8 are ets 51 mounted on theja ck'shaft 48 and drives sired number of cylinders.

operativelyfconnected to pistons in any con:-

ventional manner, The pistons are operable in" cylinders 22: which are" suitably water-jacketed,

I valve stem guides serve to support'and guide intake and exhaust valve stems 129; which carry cured as shown at 46 to the walls of the cylinder block. The plates M act as a shelf to prevent the repairing of the motorjor replacement of the "sprockets 58Iare formed integral with a slight above the cylinderand is secured to the'cylinder in any conventional manner, being separated therefrom by a gasket E l. 'Ihe'cylinder head is properly cored, as shown at 26, for enabling the circulation of cooling water through the head; I '5 Located in the cylinder head, preferably directly above each cylinder, is a pair or bored openings 21. In each. of the bored openingsof the cylinder heads isa' valve stem guide 28. The

atftheir lowerfen'ds intake and exhaust valves 3i. Thevalvev stems extend upward above the cylinder head and are provided withconcentrically arranged valve springs 32'held in position by spring hoods 33. The springs normallyr-etain the valve stems in their uppermost position so that the valves are held on their seats in a closed position. I I

Integral with the crank shaft l! are a pair parts from dropping into the crankcase during chain drive presently described. v 3.5

The connecting rods, 42 are connected to cranks 47, which are offset'90 degrees-' froin each. other -(Fig. 4) and are formed integral'with' a jack shaft '48. The jack shaft-l8 is mounted in suit: able bearings, half of which, as shown'at '66, are

', formed integral with the cylinder. block; and the other half 'of which, as shown at vEL-are formed integral with a one piece casting 52-; The casting 52 is secured-ito ,the cylinder block by means or" studs 53 (see-Fig. 2). The casting 52 is'suiti ably cored out, as shown at 54, to'enable the operation of the cranks 47 and issuitably shaped to providetspace for the operation of a timing chain56. j I

The timing c ain is driven by a pair of sprocka pair-of spr'o'ckets:58 mounted upon a cam shaft Preferably the sprockets 51 and also the space between them for-the receptionof a web 85 head. The slots, except for the portio-n thereof on the chain as is well known in the art to which this invention applies. The casting 52 serves as a support for the cam shaft 59. Mounted on the cam shaft are a pair of bushings 6| which are supported from the casting 52 as shown at 62. A pair of caps 63 serve to hold the bushings 6! in position.

As shown in Fig. 5, the cam shaft is provided with a hub 64 upon which the sprocket wheel 58 is mounted. A plate 66 is bolted, as shown at 67, t0 the sprocket wheel and is held against endwise movement to the right, as viewed in Fig. 5 by the interengagement of frustro-conical surfaces formed on the plate and the hub 64. In assembling the sprocket wheel on the cam shaft 59, the hub 64- is moved to the right until The cam shaft 59, in addition to being supported by the casting 52, has bearings, generally indicated by the numeral ll, spaced along the cam shaft. These bearings, as shown in Fig. 3, comprise bridging plates 12 generally U-shaped, which are supported by studs 13 which extend through bores in the cylinder head l3 and are threaded into the cylinder block H, as shown at M. Nuts it serve to hold the studs in position. At their upper ends the studs are provided with shoulders 11, which serve to support the bridging plates 12. Bearing caps 18, held in position by studs 19, retain the. cam shaft in position.

Mounted on the cam shaft are a plurality of cams 85, which are adapted to engage cam plates ill. The cam plates 81 may be formed integral with rods 88, which are connected to the valve stems. The rods- 88 have fiat spots 89 to enable the convenient use of a wrench for adjusting the rods 38 with respect to the valve stems so as to adjust the valves 3| so that they may be properly timed. An oil hood 9| may be provided to enclose the timing chain and sprocket to prevent oil from being splashed over the top of the cylinder head. The oil hood 9| may be slotted as shown at 92 at its sides so as to fit down over the cam shaft. Flanges 93 may be provided on the oil hood for the reception of screws for securing the oil hood to the cylinder through which the cam shaft passes, may be closed by pivoted closure plates 94, which, after the oil hood is in position, may be moved to substantially close the slots 92. An engine hood 96 may also be provided to enclose the valve assembly and thecam shaft.

The operation of the internal combustion engine of my invention will be apparent from the above description without further explanation.

, It is sufficient to state that the crank shaft,

The left-hand bushing BI is then movedthe cam shaft 59. Rotation of the cam shaft causes the'cams 8| to actuate the valve stems 29. Actuation of the valve stems opens and closes the valves in timed sequence with the operation of the pistons, so that the intake and. exhaust valves are opened and closed at the proper times during the cycle of-operation.

One of the important features of my invention is the fact that certain of the prevalent sources of noise in the overhead valve type of engine are eliminated. The intake and exhaust valve operating mechanism is driven directly from the cam shaft without the long push rods and. the rocker arms normally employed in the overhead valve type of engine.

A further important advantage of my invention is the ease with which the timing chain, if it should break, may be removed and replaced.

All that is necessary is to remove the engine hood 96 and the oil hood 9|, separate the ends of the chain by removing the pin normally employed to join the endstogether, to thereby enable removal of chain from the sprockets. A new chain may then be-readily positioned on the sprocket and the ends joined upon inserting the pin in the ends of the chain. Theoil hood 9I' and the engine hood 96 may then readily be replaced. If any damage should occur to the jack shaft E8, the sprockets 5'! or the cranks 4'1, the entire casting 52 maybe conveniently removed by first removing the timing chain 56, then the cam shaft 59, after which the studs 53 may be loosened to enable the casting 52 to be lifted out of the space between the sections of the cylinder head.

While I have described the preferred form of my invention, it will be apparent that various changes and modifications may be made, particularly in the form and relation of parts without departing from the spirit of my invention as set forth in the appended claims. e

' I claim: e

1. In an enginehaving a crank shaft, a cylinder block wherein a plurality of cylinders are provided and a cylinder head wherein a plu-' ralityof intake and exhaust valves are mounted,

a casting mounted .in said cylinder head I and supported from said cylinder block, a cam shaft supported from said casting, means for operating said valves from said cam shaft, and means extending through said cylinder block for driving said cam shaft from said crank shaft.

2. In an engine having a crank shaft, a cylinder block wherein a plurality of cylinders are provided and a cylinder head wherein a plural.- ity of intake and exhaust valves are mounted, a

casting mounted in said cylinder head andsup-g ported from said cylinder block, a cam shaft supported from said casting, means for operating'said valves from said cam shaft, and means including a jack shaft and a chain for drivin said cam shaft from said crank shaft.v s

JOSEPH R, mam-.1 l

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