US1794928A - Internal-combustion engine - Google Patents

Description

March 3, 1931. w. F. SMITH INTERNAL 'COMBUSTION ENGINE 2 Sheets-Sheet l' original Filed May 2s, 1924 iNvENToR r 5L, L Q

MM ATTORNEY oooooo March 3, 1931. w. F. SMITH 1,794,928

`IN'IRNAL COMBUSTION ENG'INE INVENTOR w. 9. Mal

'LATTORNEY Patented Mar. 3, 1931 v UNITEDSTATES PATENT orifice WILLIAM F. SMITHi or roUGHKEErsIE, NEW YORK, AssrGNon `or ONE-HALF To HERMAN A., scHA'Tz, or,Porienxnnrsrn, NEW YORK INTERNAL-COMBUSTION ENGINE Urgn'al application filed May 23, 1924, Serial No. 715;338. Divided and this Aapplication filed .'anual'y This invention relates to improvements in internal combustion engines, and particular'- ly to .gasoline engines of the socalled air cooled type. This is a division of my copendingapplica-tion Serial No. 715,338, filed nengine,` preferably by passage through achaniber in contact With the cylinder head. In order toinereasethe volumetric efficiency of the engine, the vaporization of the fuel takes place before itis mixedwith air, Whereby air reaches the cylinder head in arelatively cold condition.

In accordance with another feature of the invention a; carburetor, 'controlling the delivery of varying amounts of fuel to the engine, is so arranged that irrespective of the quantity of fuel delivered to the engine, the proportions of the fuel mixture remain constant.- The' carburetor herein disclosed is particularlyadapted for mixing vaporized hyd-rocarbon with air.

Further features of theinvention have to do with the cooling of the cylinder and cylinderliead.

In accordance with the present invention fins or webs project from both the cyl inder' and the head, exposing a large surface tofair drawn in by a blower. The construction is so provided that, asv far as possible, these fins are keptintaet. The screws by means of which the head is attached to the cylinder, are at right anglesto the vertical axis thereof, avoidingthusthe necessity of cutting aW'ay coolingfins for the purpose of giving access to such screws. The cylinder head is-cast ofsubstantially uniform thick ness throughout. Thiseheapensthe casting and insures rapid and uniform cooling of the head and uni-form protection to the valves.

This result is enhanced also by the manner in Whiehthe vhead is adjusted to the cylinder.

Serial No. 1,901.

These and other features of the invention will more clearly appear from the following detailed description and the claims. The invention is disclosed as applied to a one-cylinde-i'gasoline engine particularly adapted for use in tractors and the like. Obviously, the various features are readily applicable to internal combustion engines of Widely varying types Without departing from the spirit of the present invention.

In the drawingsFiv'. 1 is a vertical crosssection of as much of a gasoline engine as is necessary for an understanding ofthe various features of the present invention; Fig. 2 is a sectional view along lines 2-2 of` Fig. 1; Fig. 3 is a plan view of a casting (131) g Fig. 4 is a cross-section of the carburetor taken along a line slightly to the right of 4-4 of Fig. 1; Fig. 5 is a similar view taken along lines 1-4 of Fig.'1 andshowving a different adjustment of the carburetor; and Fig.- 6 is a'sectionalview along lines 6 6 of Fig. 1.

Referring to the drawings, 1 is a cylinder provided with a plurality of annular webs or finsv 2, entirely surroumling the cylinder and which serve as cooling surfaces. These fins are increasing in Width as the head 2% is approached, whereby the cooling surface varied, depending on the amount of heat to be dissipated. The cylinder head is also provided With annular cooling iins 4L and with other cooling surfaces to be hereinafter referred to more in detail. inasmuch as the heatdeveloped is greater in the engine head, proper cooling thereof is of prime importance. The cylinder head is provided with apcrtures and 6 through which tivo spark plugs, such as 7,1 may be inserted. The fins or Webs 8, 9 and 1() at the end ofthe cylinder 1, are so shaped that they form a seat for the head 3 and contact, in the order named, with a sloping Wall 11 ofthe-head and the inside surface of iins 12 .and'13. 1&2- and 13 are the lastfins projecting from-the head 3,- the vconnection between the base of the fins andthe head being by means of webs such as 14 and 15. Six or more of the WebsA 15 have screen threaded holes With which screvv-threaded lugs, such as-16, cooperate. The ends of the lugs 16 are tapered and are adapted to engage the correspondingly tapered lower surface of the web 9. In assembling the engine, the sloping wall 11, wedged on the correspondingly ysloping ring 8, insures a tight closure'for the cylinder. The cooperation between webs 12 and 13 on the head, and 9` and Y 1,0 on the cylinder makes possible proper fitting thereof. The screws 16 are accessible from the side without the necessity of cut-A ting away any of the fins above and below them and are tightened one after the other, drawing down the head over the cylinder. Inasmuch as the contact between webs 12, 13 and 9, 10 is at an angle to the contact betweenl 8 and 11, the danger of the head being tipped Ato one side during the tightening of screw 16 is avoided. The head is in direct contact with the cylinder, the necessity of providing gaskets or other forms of packing being avoided. Gwingto this arrange ment heat developed in the head is dissipated, not only through its fins but also through the cylinder 1. vAnother important feature of the present arrangement of attaching the cylinder head is that no large bosses need be provided at the points where the head and the cylinder yare bolted together. Large sections of the cooling surface would have to be cut away to make such bolts accessible. Furthermore, the casting ofthe head and the cylinder would be more difficult on account of the unequal vthickness of the various parts which, of course, do not cool at the same rate, resulting'in distortion of the Acast-ing.

The sloping wall 11 of the head forms for a space one of the side walls of the compression chamber 17 and is surrounded by an annulaichamber 18 bounded by three cooling fins 19 forming part of the cooling system of the cylinder head. The fins 19 are not of the same width all around the cylinder head. At one point two of these fins are elongated into fins'20 and 21 which terminate in a seat 22. The annular passageway 18 opens into a chamber formed by the .fins 20 and 21. At-

tached to th-e seat 22 is a casting 23 connected with the gasoline tank at 24. The fiow 'of gasoline through 24 and a 'vertical bore 25 into the casing 23 is controlled by means cfa-needle valve 26 controlled in turn "by a float 27 responsive to the level of the liquid in casing 23. 28 is a draining plug for the casing 23. Gasoline from the casing 23 passes through a channel 29 controlled by another needle valve 30 through a tube 31. The tube 31 is set into the casing 23 .and is surrounded by a second tube 32. The cylindrical space between the concentric tubes 32 and 31 is in communication with the outside atmosphere through a valve 34, which is provided with the usuall vertical and horizontal perforations (not shown). The ends of tubes 31 and 32 are tapered and vin close proximity to each other so .as to produce'the well known Ven-f turi tube effect. These tubes project within the chamber afforded by the fins 20 and 21 and send a spray of gasoline and air mixture right and left through the passageway 18 around the head 3. Access may be had to the float 27 by removing a cover plate 40 which is attached to aboss of the casing by means of screw 41. f e j T he top of the cylinder head 3 is provided with two perforations 45 and 46 which, serve as seats for intake and exhaust valves 36, 42, the stems 38, 43 of which project through perforations 50 and 51 provided in a boss 52 and cast integral with the 'cylinder head. The valve stems project within a housing 62 attached to the head at 54 and are controlled by springs 37, 44,cams 39, 47 on rocker arms like 48 and push rod 61 in the well-known m anner. It will bev noted that the valves are of relatively large diameter permitting com-;

plete scavenging action which is facilitated also by their location in the head. .It is necessary that a uniform'section of iron and free circulation of air be permitted around the valve seats, particularly the seat 45 for the.

total iron on the other sides of these valveAV seats. Furthermore, the cooling effect of air passing above 64 between webs 53 is about the same as that of air passing between webs 56 and fins 4 adjacent to the other sides of the valve seats.

The valves, and Vparticularly the exhaust valve, is further protected fromV injury by heat by the provision of two spark plugs and by the location thereof. 'Ihese spark plugs 7 are placed at diametrically opposite points of the head between the two valves. The vertical ases of the spark plugs are at an angle to t-he vertical axis of the cylinder. The spark plugs are simultaneously actuated and owing to the manner in which they are placed in the head, the flames of theeXplosion will unifori'nly surge around the chamber 17. IVith a single spark plug, most of the flame is sucked towards the exhaust port, resulting in burned-out or warped valves.-

In order to make room for valves 36, 42 of sufficiently large'diameter and also to have sufficient space between them for the free circulation of air, the head 3 is so shaped that the length on the axis of the valves is greater than the diameter o'f thecylinder 1, and the mouth of the cylinder is flaring. In order, however, to reduce the compression chamber within the heady to the required volume, the head is constructedwith an oval section tapered outwardly. This will be clear from Fig. 2, which is a vertical crosssection taken between the two valves. Afurther advantage of the present construction resides in that the valves are in alignment with the vertical axis of thecylinder, whereby the machining and grinding operation are facilitated and the lcomiection with the cam shaft issimplilied.

` eleeye^ provided with allange 71 Whichsets vOna gasket '.72 provided in the seat, the positieningl ot the Sleeve 70 with respect to the seat 58 being determined .by a doWel pin (not elio-Wn) .projecting from the sleeve andi cooj erating with asuitably located hole in tne seat 59. The sleeve provided with two perforations 74 and 75. The sleeve 7 Ots Within a longitudinal bore provided in a cylindrical casting77.` The casting 77 is provided with a short 4horizontal shaft `78 .and With three Vannular ridges 79,l 80 .and 81, forming `the side Walle otatwo annular' chambers82and 88. The Wall of the cylhider 77 is `provided with two pertorations Sea-nd which connect .the chamber 76 with the annular chambers 82 and 83, respectively. The diameter ot .the perforations 84. and 85 is the same as .that of perforations 74 and 75 in the sleeve 70 .and are so located that when the sleeve is encloeed by casting 76,` the two sete ofxholes will register. Short sleeves 88, the inside dianieter oi Which is' the Same as that of 84 and 85,:1nd which project :bore the bottom of chambers 82 and88, are held in enlargements of apertnre'a 8l and 85. The cylinder 77 is. enclosed by and :tastened to a cylinder 87. A blade 00 projects 'adiallyfrom cylinder 77 parallel with its; longitudinal axis ,and .opposite the ajiertures 84,85. rThe blade 60 is substantially coeiitensi'vewith cylinder 77 and projects the full height of chambers 82, 83. The walls ofV cylinder 87 are pro-vided With two pairs of diametrically opposite perfor- ations 88 and 89, the diameter of which is the same as the Width ot the annular chambere82 and 83. Furthermore, the cylinder 87 is provided with two pairs of diametrically opposite pcriterations. 90and 91. The centers of perforatio- ne 90, 91 and 88, 89 arcin alignment, but

:the smaller perf'orations are not provided exder 87. The cylinder @terminates in allangc 95 engaging a gasket-0G provided on acircular seat n07 providedon casting 49 forming part of cylinder head 3. The end wall 95 of the cylinder'92'is perforated and shaped tov forni a-beari1ig through Which the shaft 78 of sleeve 77 projects.

` The mixing device is assembled by first assembling 70, 77, 87 and 92, and then positioning it yin seat 59 by Ameans of pin 78, Whereupon the Whole assembly `is fastened 'into place by four screws ad, by means of which flanget of cylinder 92 iszheld against seat 9.7. The heads of screws 1000 and (l are counter-sunk in the flange, but `the heads ot The ridge 105 is provided With a plurality oi slanting notches 108 for receivingthe stenrot Spring102. The annular `chamber 109 formed by casting 101, is enclosed by a `second casting 110 which is held against shaft 78 by means of a setserew (not shown). The caet` .t

ing 1'10 carries fan bladesI 1-12 and 112a'taetened thereto `by means ot'scrcus 118. 'llhe boss 100 has rib 128 adapted to engage the heads of screws 100e and 1000` andzthus limit the rotation ot 101 between these Screw heads. The movement of thecaeting may be brought about by means oi a wire 119 supported on :ribose 120 ot the cylinder llead and controlled in turn by the operatorls throttle lever (not shown). IThe Wire 119is attached to the bossi 100 by means of a Screw 118.

The rotation of 101 is transmitted to '110 by means of the wire 102, the tail 101- 01" which projects within an aperture in casting 110.

The caSting110 is positioned with respect to.4

the casting 101 by means of a pin 120 projecting from 110 and engaging the slopingl end oi a screw 115 held in bose 107 of' casting 101.

Attached to the casting 181 is a plate 1130.

The cylinder 1k is bolted vto `this casting 131 at 132` 133, 18%!- and The 'twopnnh rode extend through pcrforations 188 and lltlin the casting 181. The casting is provided with ridges forming Substantially tWo parallelograms 14:0 and 141 in-tei'coni-xected by menne ot a narrow ridge 142. and ridges lea-nd 14.4 terminating in a point 1115 midway between the channel 205 formed by 1110 and 141. A, plate 1116 is fastened to the casting 181 'by means of screws 1117 engaging the riddes.

25 71 t5 XJ The plate extends ytothe cylinder and is provided' with two perfor-ations 148 and 149. The plate is raised aro-und the perforation 149 to form a neclt 150 onV which its'pipe 151. The other end of pipe -lilivs' fastened by means of ya screw 152 to a seat 59 formed in head 3. The opening 148 coincides with an opening 153 in a casting 154 on which is mounted at 155 a blower 156 suitably carried in ball bearings and driven by means of a belt 157 from the Vcrankshaft or other suitable source. f

The `operation of the engine will now be described. Y

Assuming that the piston 200 in cylinder 1 is just descending, gasoline will be drawn from vtank 201 through pipe 202 and thence through channels 24, 25 past they needle valve 26 through channels 29, past needle valve-30, through tube 31 at the nozzle of which it will be mixed with air rushing in past the needle valve 33 through the tube 32. u Theparticles of gasoline suspended in the air will be sent in a right-hand and left-hand direction through the annular chamber 18, and by coming thus into contact with the hot cylinder head, willV be completely vaporized .by 'the time they reach chamber 57. Liquid particles that reach chamber 57 will flow back into contact with the cylinder head, owing to the slope at 58. Assuming that the throttle is wide open, air drawn in by the blower 156 is streaming into the channels 203, 204, and then turns at right angles into the channel 205 and through 153 into the outside atmosphere. Part kof the air drawn through channel 205 will be divertedup through the pipe 151, owing to the suction exerted by the descending piston. Inasmuch as the passage of air from the outer atmosphere through 205 and then 151 is twice interrupted at substantially right angles, hard particles such as sand th at might be suspended in the air will, by their own momentum, continue to travel, drawn by the suction ofthe blower through channels 205 and 153. Such hard particles are aided in their tendency to travel through the channel 205 by the fact that the channel 153 is tapering, whereby it acts as a Venturi tube and accelerates the movement of such heavy particles.. This arrangement constitutes an air cleaner which, without the use of anyV screens, felt pads or the like, that need constant cleaningand adjustment, insures that air deprived of all hard gritty substances thatmight injure the cylinder walls, pass through the tube 151'. Light particles, such as scraps of grass that might be drawn through 151, will of course be `destroyed by combustion and cannot, at any event, injure the cylinder.

Assuming that the throttle is wide open and that therefore the carburetor is in the position illustrated in Fig. 4, air drawn up through openings 94 and 89 is divided by rib 60 into two equal columns and passes through annular chambers 82 and 83 and thenceupwards through openings 88 and 93. This air is mixed at the nozzle of sleeves 86 with gas drawn through'ropenings 74, 75 and 84, 85.

' The intake valve 36 is opened at this time and the mixture of gasoline and air is sucked into the cylinder. In the well-known manner, upon the return movement of the piston 200, the mixture is compressed inthe cylinder, the valve 36 being closed.v At the proper instant a spark is produced at the points of the spark plugs and the compressed gasoline mixture is exploded, causing the return movement of the piston 200. In the well-known manner, the exhaust valve 42 is opened at this time and the dead gasesV are `permitted to escape through the exhaust port 63.

When the operator desires to slow ,down the enginefhe-will press down wire 119, causing thus the casting 105 to rotate in a counterclockwise direction (see Fig. 6). The rotation of casting 106 is transmitted through the agency of spring 102 to the castingL 110 and the latter, through the agency of the shaft 78 to which it is attached, will cause the rotation of sleeve 77 and cylinder 87 `in a clockwise direction see Figs. 4 and 5). The further the shaft 78 is rotated, the smaller will be the aperture through which air can enter at.89 and 94. However, at the same time the opening through which gas can escape at 74 is correspondingly restricted, insuring thus that the ratio between gas and air, as predetermined by the location and size of the vanious apertures, be retained irrespective of the total quantity of mixture sucked into the cylinder. The air that is mixed with the vaporized gasoline is not preheated, thereby the efhciency of the engine is materially increased.

As will be apparent from Fig. 5, the purpose of the blade 60 is to insure that when the airintake port is restricted by the manipulationl of the throttle, most of the air Ybe forced to pass to the right of sleeve 86, insuring thus proper intermixing of the two gases. The blade 60 offers sufficient resistance to the passage of'air through what would be otherwise the wider channel.

If it is desired to stop the motor, then the operator continues to depress wire 119, Vcausing the clockwise movement of 7 7 and 87 (Fig. 5). A point will be reached where both openings 94 and 93 are closed and neither gas nor air is delivered tothe engine. However, on account of the momentum of the liywheel, the engine might continue to operate, causing the ignition of residual gases. In order to avoid the necessity of brakes, ignition controlling switches or the like, that would be otherwise necessary to bring the engine to a dead stop, the device is so arranged that by continuing the movement of thethrottle in the same direction past the last mentioned closed position, the small apertures 90 and 91 will register with the openings 93 and 94, drawing air through such openings into channels 82, 83 and thence into the cylinder head. Inasmuch as the aperture 7 4v is now closedby the wall of 77, no gas is delivered to the cylinder.

This will prevent further functioning of the engine.

Air drawn by the blower 15G over the cooling surfaces of the cylinder and the head will impinge upon fan blades 112 and 112er. When the air thus drawn past the blades 112 and 112@ attains a certain velocity, it turns, through the agency of these blades, the casting 110 and therethrough 87 and 77 in a clockwise direction (Figs. 4 and 5), shutting off the gas supply to the cylinder. The purpose of this arrangement is to prevent unnecessary racing of the engine which would occur, for instance, when the load is suddenly taken off the engine.

That I claim is:

1. In a gasoline engine, a cylinder head, cooling fins projecting therefrom, a chamber surrounding said cylinder head constituted by the walls of two of said fins, means for spraying gasoline into said chamber, and means for mixing the vapors escaping from said chamber with air and delivering it into said cylinder head.

2. A gasoline engine containing a combustion chamber, the wall surrounding said chamber containing a conduit, means for spraying gasoline into said conduit at one point, a carburetor, and a channel leading downward from said carburetor to said conduit at a diametrically opposite point.

3. In a gasoline engine, a carburetor, a cylindrical chamber therein, an annular chamber surrounding said cylindrical chamber, means for supplying gasoline vapors to said cylindrical chamber, said' cylindricali chamber having a relatively small opening through which it communicates with said annular chamber, a pipe projecting from said opening into said annular chamber, said annular chamber having two relatively large openings, one in communication with the outside atmosphere and the other with the engine, a wall in said annular chamber, and means for simultaneously varying all of said openings and moving said wall with respect to the opening exposed, to the outside atmosphere.

4. In a carburetor for gasoline engines, two stationary cylinders, one surrounding the other, two movable cylinders fastened to each other and positioned between said stationary cylinders, said movable cylinders forming an annular chamber, the inner one of said stationary cylinders having a relatively small opening, the inner one of said movable cylinders having a corresponding small opening, the outer one of said movable cylinders having two relatively large openings therein, the outer one of said stationary cylinders having two corresponding relatively large openings, the outer one of said movable cylinders having two relatively small openings therein at different angular distances from the large openings therein but in alignment therewith,

a web projecting from the inner one of the movable cylinders into said annular chamber, means for supplying air to one opening of the outer stationary cylinder, a connection leading to the cylinder head from the other opening in the outer 011e of said stationary cylinders, and means for supplying vaporized gasoline to the inner one of said stationary cylinders.

In an internal combustion engine, a carburetor divided into two chambers, means for supplying fuel to one ot said chambers, the other chamber having two openings in the Walls thereof, one in communication with the outside atmosphere and the other with the engine, each chamber having an opening through which said two chambers intercommunicate, a single valve unit comprising a plurality of ports for simultaneously varying all of said openings, for closing the opening through which said chambers intercommunicate and for admitting air to the engine through said other chamber.

6. In an internal combustion engine, a cylinder head including a valve port, a conduit and two spaced chambers into which said conduit opens,means forintroducing fuel into one of said chambers, a connection between the other chamber and the valve port and means for supplying air to the other chamber.

In testimony whereof, I have signed my name to this specification this 3rd day of January, 1925.

WILLIAM F. SMITH.

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