US1437738A - Engine - Google Patents

Description

C. E. SARGENT.

ENGINE.

APPLICATION FILED DECZS. 1918.

Patnted Dec. 5, 1922.

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C. E. SARGENT.

ENGINE.

, Y APPLICATION FILED DEC.26, 1918. Ly. Patented Dee. 5,1922.

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Patented Dee. s, 1922.

UNITED STATES PATENT OFFICE.

CHARLES E. SARGENT, 0F INDIANAPOLIS, INDIANA, ASSIGNOB T0 MIDWEST ENGINE COMPANY, OF INDIANAPOLIS, INDIANA, A CORPORATION OF INDIANA.

ENGINE.

Application filed December 26, 1918. Serial Ho. 268,371.

To all whom it may concern:

Be it known that I, CHARLES ESARGENT, a citizen of the United States, residing at Indianapolis, in the county of Marion and `State of Indiana, have invented a new and useful lngine, of which the following is a specification.

In oil engines in which the heat of coinpression is used to ignite the fuel injected into the combustion space, such compression must ordinarily be relieved when starting the engine until the fly-wheel has gained sufficient momentum to carry the engine through the compression periods under normal compression. Ordinarily this compression relief is obtained by holding the exhaust valve open until the fly-wheel has reached proper speed, which may require anumber of shaft revolutions. While the compression is thus relieved, it is desirable to cut off the fuel feed to the engine, so as to avoid filling the fuel chamber and flooding the combustion chamber, with the possibility of premature and dangerous explosion; and to do ,this

the fuel cocks have ordinarily been shut off until compression is allowed to begin. though this is easy in a single cylinder engine, it is quite difficult in multi-cylinder engines.

It is the fundamental object of the present invention to provide an arrangement whereby the relief of compression automatically cuts ofi:z the fuel, and, conversely, the stai-ting of compression permits the feeding of fuel. It is my further object to do this through a centrifugal speed-responsive mechanism which in normal operation controls the fuel feed to govern the speed. In addition, it is my object to connect this fuel-feed governor with the associated clutch mechanism when the engine is connected with an automotive device, so that the releasing of the clutch cuts down the fuel feed s0 as to maintain the engine in operation at only idling speed. lt is a further object of my invention to provide an overhead cam shaft with proper dust-protection and lubrication, and to associate it with the engine valves so as to rotate them on their seats and thus lessen or completely avoid the necessity for valve grinding. Among furtherobjeots of my invention are to arrange the fan so that it has a combined friction and gear drive; to provide an automatic oil-pressure governor to make it o sible to adjust the centrifugal speed-resorisive device and the oil-pressure governor while the engine is running; and to draw the air for the fuel feed from the same conduit as the main air, so that a single air-Washing device may be provided and the air which is drawn into the fuel cup or ignition chamber will be free from dust and the outlet of the fuel cup will be prevented from becoming clogged.

I The accompanying drawings illustrate my invention: Fig. 1 is a vertical longitudinal section through a four-cylinder engine embodying my invention; Fig. 2 is a detail view of a fragment of the cam shaft, showing the cams for one cylinder, and showing the exhgust valve associated with the exhaust cam; lig. 3 is a transverse vertical section ona somewhat larger scale through the upper part of the engine, showing part of one of the cylinders and the mechanism above it. and being taken partly on one plane andl partly on another, and also showing the arrangement of cams for one cylinder, the ca'ins for the other cylinders being omitted; l* 1g. 4 is afragmentary side elevation of the rear end of the engine and an associated clutch, showing the interconnection of the clutch to the fuel control; Fig. 5 is a fragmentary rear elevation of the engine; and F ig. 6 is a detail showing the oil-pressure regulator.

The engine shown has four cylinders'l. the pistons 11 of which are connected in the usual way to the crank shaft 12 which is mounted in suitable bearings 13, 14, and 15 in the oil-tight crank casing 16. 0n the rear end of the crank shaft 12 is a fly-wheel 17, beyond which may be a clutch 18 which is operated by .a fork 19 in the usual manner.

A bevel gea-r 2O on the crank shaft 12 near the front bearing 13 meshes with gears 21 and 22 on the driving shaft of a gear pump 23 and on an upwardly extending shaft 24. the latter shaft being provided at its upper end with a bevel pinion 25 which meshes with a bevel gear 26 splined on an overhead cam shaft 27, which extends over all the intake valves 28 and exhaust valve 29 of the several cylinders 10 and is provided with proper cams 30 and 31 for operating said inlet and exhaust valves respectively. All

these valves are shown closed in Fig. 1, `no.

' tirely eliminate the necessity for Valve grinding. A valve spring 33 acts on each valve stem through a thrust bearing 34 to keep 'the valve normally seated.

The' exhaust valves 29 act in the usual manner to discharge the products of combustion from their associated cylinders.'

rlfhe intake valves 28 act to admit pure air from the passage 35, which may be supplied with such pure air through any suitable airpurifying device, such as shown in my copending application Ser. No. 244,724, filed July 13, 1918. No fuel is admitted through the air supply passage 35 or the intake valves 28. Instead, for each cylinder, the fuel is supplied, mixed with a small quantity of air drawn through a branch passageway 36 which I arrange as a branch from the main air passage 35 so that such air is also free from dust, through a fuel valve 37 to a fuel cup or ignition chamber 38 located in the top of the cylinder 10 and communieating with the combustion space in the cylinder through one or more very small holes 39. Each fuel valve 37 is spring-pressed to closed position by a compression spring 40, but is opened against the action of such spring by a lever 41 actuated by a fuel-feed cam 42 also mounted onh the cam shaft 27. The fuel supply passage 43 controlled by the fuel valve '37 opens in the valve seat of such valve, so as tocut off fuel flow when this valve is closed.

In each fuel passage 43 there is also a controlling valve 45, which is a needle valve which closes downwardly but is springpressed upwardly or toward open position by a compression spring 46. The upper end of each needle valve 45 is held by the spring 46 in engagement with an adjusting screw 47 on an arm 48. All the arms 48 are mounted on a rock shaft 49 which extends parallel to the cam shaft 27. By turning the rock shaft 49, (in a counterclockwise direction in Fig. 3 or in a clockwise direc-tion in Fig. 5, these two views being taken from opposite viewpoints,) the arms 48 are depressed to force down the needle valves 45 against their opening springs 46, thus cutting down or v completely shutting off the fuel supply,

The rock shaft 49 may be operated in several ways-by the releasing of the clutch 18, by the speed-responsive action of a centrifugal governor, and by the action of the compression-relieving means when starting the engine. These will be considered sepa.- rately.

For operating the rock shaft 49 by the releasing of the clutch, such shaft has a lever 5U on its rear end outside the engine casing. This lever 50 is not quite rigid on the shaft 49, but is capable of a limited turning movement relative thereto, as by a cross pin 51 fixed in the shaft 49 and extending in circumferentially elongated slots 52 in the hub of the lever 50; so that when the lever 50 is turned in a clockwise direction (Fig. 5) it carries the rock shaft 49 with it, but so the rock shaft can turn inthe same direction for a limited angle without movement of such lever. One end of/this lever is provided with a stop screw 53 co-operating with a fixed stop 54 from the engine casing to limit the valve-closing movement (or clockwise movement in Fig. 5) thereof. A long slender link 55 is suitably connected to the other end of such lever 50 and to one arm of a bell-crank 56 mounted on the clutch casing so that its other arm co-operates with the clutch-setting fork 19. When the clutch 18 is released. by the movement of the fork 19 to the right in Fig. 4, such fork 19 moves the bell-crank 56 in a clockwise direction (Fig. 4) to lift the link 55 and that end of the lever 50 which is connected with such link to the point determined by the setting of the stop screw; 53. The long slender link 55 has sufficient resiliency so that it may buckle slightly without 'permanent distortion if the releasing movement of the clutchsetting fork 19 continues to move the bellcrank 56 after the stop screw 53 has stopped the movement of the lever 50. This clockwise movement of the lever 50 carries the rock shaft 49 with it, and closes the needle valves 45 to the extent determined by the stop screw 53; which is set so that the needle valves 45 will allow just enough fuel to pass to idle the engine with the clutch released, thereby preventing racing.

For operating the rock shaft 49 in response to the speed, the bevel gear 26, which for reasons hereinafter apparent is itself splined on the cam shaft 27 so as to permit such cam shaft to move through it without interfering with its meshing with the bevel pinion 25, is provided with a cone flange 60, between which and a fiange 61 of a sleeve 62 fitting loosely on the end of the cam shaft 27 are a seriesof balls 63. A compression spring 64 mounted in a screw cap 65 by which its tension may be adjusted even when the engine is in operation, acts through a thrust bearing 66 to force the sleeve 62 and its flange 61 toward the cone fiange 60. When the engine is in operation, the balls 63, as centrifugal force tends to throw them outward, act between the cone flange 60 and the straightffiange 61 to tend to force the sleeve 62 to the left against the action of lthe compression spring 64. The sleeve 62 is provided with a cone 67, which acts on an arm 68 fixed on the rock shaft 49, so that as the sleeve 62 is forced against the spring 64 the cone 67 acts through the arm 68 to turn the rock shaft 49 in a counterclockwise direction (Fig. 3) to force the fuel needles 45 toward their seats against the action of their springs 46, to cut down the supply of fuel and the speed of the engine, thus maintaining the enginespeed constant within the limits of the governor.

For operating the rock shaft by the compression-relieving means when the engine is started, the camshaft 27 is provided with a valvefdepressing cone 70 for each exhaust valve 29, and is mounted for endwise movement in its bearings. Normally the governor spring 64 holds the cam shaft 27 to its right-hand limit of movement (Fig. 1), acting through the sleeve 62 and a shoulder on such cam shaft against which such sleeve bears. In such normal condition, the several cones 70 are out of engagement with the associated exhaust valves. The opposite end of the cam shaft 27 from the governor spring 64 co-operates with a cam 71 on a cross shaft 72 mounted in a suitable bearing 73 on the engine casing and provided with anv arm 74 connected by a link 75 to any suitable. control point. By operating the link 75 the shaft 72 is turned, and the cam 71 forces the cam shaft 27 to the left (Fig. 1) against the action of the governor spring 64. By this longitudinal movement of the cam shaft, the several cones 7() engage the associated cup-shaped members 32 to force open and hold open the several exhaust valves 29; and at the same time the sleeve 62 with its cone 67 is carried to the left,- and the cone 67 acts on the arm 68 to turn the .rock shaft 49 and force the fuel needles 45 to their seats to shut off the fuel supply While the exhaust valves are held open. This permits the engine to be started with compression relieved, and prevents the evils consequent upon supplying fuel to the engine when by reason of lack of compression no ignition occurs.

The gear pump 23 is mounted in the bottom of the crank casing 16, and has a screened inlet at the low forward end of such crank casing. The discharge side of the pump 23 leads by way of an opening 82 to an axial hole 83 through the driving shaft of such gear pump, which hole in turn leads to an opening 84 in the main crankshaft bearing 13. This supplies oil to this main crank-shaft bearing, and through suitable holes 85 in the crank shaft and other parts also supplies oil in a well-known way to the other main crank-shaft bearings and other associated bearings only tihe beginning of this passageway is shown, because this particular passageway forms no part of my present invention. main bearing 13 communicates by the circumferential groove in the crank shaft at such bearing with an axial hole 86 extending through the shaft 24. The hole 87 communicates at its upper end, by'way of an opening'87 connecting its upper bearing and one of the bearings of the cam shaft 27, with a longitudinal hole l88 through such cam.

The hole 88 communicates through shaft. various cross holes 89 in the several crank shaft bearings and' cams 30 vanel- 31 with the several points of friction which the cam shaft has. The oil flows out through these cross holes 89 on to the floor 90, in holes 91 in which the inverted cup-shaped members 32 have their guiding mounting, said members 32 projecting upward above such floor; and this oil forms a thin lm over'` this floor, the excess of oil passing around the sides of the left hand bearing (Fig. 1) of the cam shaft and falling through the hole 92 through'which the shaft 24 extends vertically.

Some of the, oil from the floor 90 seeps into the holes 91 to lubricate the sliding bearings of the inverted cup-shaped members 32 therein. In order to prevent this oil from completely filling the holes 90 and from seeping down on to the valves 28 and 29, the boss 93 for the stem of each of these valves extends upward in the hole 91 beyond the level of the lower edge of the cup-shaped member 32 when the latter is in its highest position, and the wall of such cup-shaped member is provided at one or more points with a longitudinal hole 94 connecting the inside of such hole 91 below the level of the top of the boss 93 with the outer space above the oil level on the licor 90. By this construction, any excess of oil which rseeps into the hole 91 is pumped out through the opening 94 as the cup-shaped member 32 is moved up and down by its operating cam 30 or 31, this excess of oil being forced upward through the opening 94 ,as the cup-shaped member 32 is depressed, while when such cup-shaped member rises only air is drawn down through the hole 94 because the upper end of such hole is above the oil level on the lioor90.

In order to control the oil pressure, I provide a tube 95 which is mounted in the engine casing and communicates with the hole 87 in the upper bearing of thevertical shaft 24 (Fig. 6). 'This tube 95 is provided with a lateral opening 96, through which oil may escape to relieve the pressure in the oiling system when such pressure rises too high. The escape of oil through the hole 96 is controlled by a plunger 97 which is pressed by a compression spring 98 to close such hole 96 from the hole 87 and shut off such escape; but as the oil pressure rises the The opening 84 in the lcarried by the engine casing.

plunger 97 is pushed back against the spring 98 to uncover the hole 96 to a greater or less extent and thus to permit any excess of oil to escape to keep the oil pressure down. Therear end of the spring 98 bears against an abutment 99 mounted on an adjusting screw 100 projecting from the exposed end of the tube 95, so as to permit ready adjustment of the spring 98 even when the engine is running; this controls the maximum oil pressure Which is developed.

The sides of the engine casing are carried up on all sides, above the cam shaft 27 and rock Shaft 49, and upon their upper ed es a removable cover plate 101 rests, to mie an overhead enclosure for the cam shaft and rock shaft and their associated parts. This protects these parts from dust, which Would otherwise interfere greatly with the practical operation thereof.

At an intermediate point, the shaft 24 has fixed thereon a bevel gear 105,'Which meshes with a bevel pinion 106 on the rear end of a fan shaft 107 'mounted in suitable bearings A cone 108 is fixed on the front end of the fan shaft 107, and the cone hub 109 of a fan 110 ts upon the cone 108 and is held frictionally thereupon by a disk spring 111 which is held against the edge of the cone hub 109 by a nut 112 on the forward end of the fan shaft 107. This makes a combined gear and friction driven fan, and avoids the necessity for belts, so that the fan may be located quite close to the engine casing, While still allowing the necessary slippage in case the fan encounters any obstruction.

I claim as my invention:

1. In an internal combustion engine, thc combination of a cylinder` having intake and exhaust valves, a cam shaft provided with cams for operating said valves, said cam shaft being mounted so that it can be shiftedvv longitudinally, a cone mounted on said cam shaft so that by the longitudinal shifting thereof said cone acts on one of said valves to open it, fuel-controlling means, and means operated by the longitudinal shifting of said camshaft in the direction to open said valve for operating said fuel-controlling means to shut oii' the fuel supply.

2. In an internal combustion engine, the combination of a cylinder having an exhaust valve, a cam shaft provided'vvith a cam for operating said valve, said cam shaft being mounted so that it can be shifted longitudinally, a cone mounted on said cam shaft so that by the longitudinal shifting thereof said cone acts on said valve to open it, fuelcontrolling means, and means operated by the longitudinal shifting of said cam shaft in the direction to open said valve for operating said fuel-controlling means to shut off the fuel supply.

3. In an internal combustion engine, the

combination of a cylinder having intake and exhaust valves, a cam shaft provided with cams for operating. said valves, said cam shaft being mounted so that it can be shifted longitudinally, and a cone mounted on said cam shaft so that by the longitudinal shifting thereof said cone acts on one of said valves to open it.

4. In an internal combustion engine, the

'combination of a cylinder having an exhaust valve, a cam shaft provided with a cam for operating saidvalve, said cam shaft being mounted so that it can .be shifted longitudinally, and a cone mounted on said cam shaft so that by the longitudinal shifting thereof said cone acts on'said valve to open it.

5. In an internal combustion engine, the combination of compression-relieving means, fuel-controlling means, a' centrifugal governor responsive to the speed of the engine, a clutch for connecting the engine to a driven device, and means for operating said fuel-controlling means by the clutch and by the compression-relieving means and by the centrifugal governor.

6. 1n an internal combustion engine, the combination of compression-relieving means, fuel-controlling means, a clutch for connecting the engine to a driven device, and means for operating said fuel-controlling means by the clutch and by the compression-relieving means.

7. In an internal combustion engine, the combination of fuel-controlling means, a centrifugal governor .responsive to the engine speed, a clutch for connecting the engine to a driven device, and means for operating 'valve means for admitting air and for discharging the products of combustion, an ignition chamber communicating with said cylinder, passages for supplying fuel and air to said ignition chamber, means for controlling the fuel passage to said ignition chamber, means for relieving the compression in the cylinder, a centrifugal governor responsive to the speed of the engine, a clutch for connecting the engine to a driven device, and means for operating said fuel-controlling means by the operation of said compression-relieving means and of said centrifugal governor and of said clutch.

9. In an internal combustion engine, the combination of a cylinder provided With valve means-for admitting air and for discharging the products of combustion, an ignition chamber communicating with said cylinder, passages for supplying fuel and air to said ignition chamber, means for controlling the fuel passage to said ignition chamber, a centrifugal governor responsive to the speed of the engine, a clutch for connesting the engine toa driven device, and means for operating said fuel-controlling means by the operation of said centrifugal governor and of said clutch.

10. In an internal combustion engine, the combination of a cylinder provided with valve means for admitting air and for discharging the products of combustion, an ignition chamber communicating with said cylinder, passages for supplying fuel and air to said ignition chamber, means for con trolling the fuel passage to said ignition chamber, means fo-r relieving the compression in the cylinder, a clutch for connecting t-he engine to a driven device, and means for operating said fuel-controlling means by the operation of said compression-relieving means and of said clutch.

1l. In an internal combustion engine, the combination of a cylinder having intake and exhaustvvalves, a cam shaft provided with cams for operating said valves, said cam shaft being mounted so that it can be shifted longitudinally, a cone mounted on said cam shaft so that by the longitudinal shifting thereof said cone acts on one of said valves to open it, a sleeve mounted on said cam shaft and slidable longitudinally thereof` said sleeve and a part rotatable with said shaft being provided with flanges which converge toward their peripheries, balls between said ianges tending to force them apart b-y the action of centrifugal force when the engine is in operation, a spring acting on said sleeve tending to force the two flanges together and to force the cam shaft longitudinally in the direction to disengage said cone from its associated valve so that the sleeve may be moved against said spring either by the action of centrifugal force on said balls or by the longitudinal shifting of said cam shaft to engage said cone with its associated valve, fuel-controlling means for controlling the sup-ply of fuel to the engine, and means for operating said fuelcontrolling means'by the shifting of said sleeve.

l2. In an internal combustion engine, the combination of a cylinder having an exhaust valve, a cam shaft provided with a cam fo-r operating said valve, said cam shaft being mounted so that it can be shifted longitudr nally, a cone mounted on said cam shaft so that by the longitudinal shifting thereof said cone acts on said valve to open it, a sleeve mounted on said cam shaft and slidable lon gitudinally thereof, said sleeve and a part rotatable with said shaft being provided with anges which converge toward their peripheries, balls between said flanges tending to force them apart b-y the action of centrifugal force when the engine is in operation, a spring acting on said sleeve tending to force the two flanges together and to fonce the cam shaft longitudinally in the direction to disengage said cone from its associa-ted valve so' that the sleeve may be moved against said spring either by the act-ion of centrifugal force on said balls or by the longitudinal shifting of said cam shaft to engage saidcone with its associated valve, fuelcontrolling means for cont-rolling the supply of fuel to the engine, and means for operating said fuel-controlling means by the shifting of said sleeve. y

In witness whereof, I have hereunto set my handv at Indianapolis, Indiana., this 16th day of December, A. D. one thousand nine hundred and eighteen.

CHARLES E. SARGENT.

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