US2231722A - Internal combustion engine - Google Patents

Description

Feb. 11, 1941. F JQHNSQN 2,231,722

INTERNAL coMUsTIoN ENGINE Filed Jan. 19, 1939 3 Sheets-Sheet 2 a/r/z/Q ATTORNEYS.

Feb. 11, 1941. F. JoHNsoN INTERNAL COMBUSTION ENGINE Filed Jan. 19, 19159 3 Sheets-Sheet I5 V.. DU

Patented Feb. 1l, 1,941

PATENT OFFICE INTERNAL coMBUsTIoN ENGINE Frank Johnson, Detroit, Mich., assignorto Ford Motor Company, Dearborn, Mich., a corporation ot Delaware Application January 19, 1939, serial No. 251,724

7 Claims.

The object of my invention is to provide improvements in the oiling system of an internalcombustion engine.

A more speciiic object of my invention is to provide improvements in an internal-combustion engine having what are commonly termed hydraulic valve tappets therein. My improvement comprises means whereby the tappets will be normally supplied with filtered oil, the unique feature being that if the oil filter for any reason becomes clogged, an uninterrupted flow of oil from the engine crankcase will be delivered to the tappets. Althoughthe system is designed for lubricating valve tappets, it may readily be adapted to supply l5 clean oil to other equipment on the engine with the added insurance that under all conditions oil will be provided.

With these and other objects in veiw, my invention consists in the means for accomplishing the above-mentioned objects, as described in my specifiation, claimed in my claims, and illustrated in the accompanying drawings, in which:

Figure 1 is a diagrammatic view, illustrating the principal elements of my improved system.

Figure 2 is a fragmentary plan view of my improved motor.

Figure 3 is a sectional view, taken on the line 3-3 of Figure 2. u

Figure 4 is a sectional view, taken on-the line 4-4 of Figure 2.

Figure 5 is a sectional view, taken on the line 5-5 of Figure 4, and

Figure 6 is a sectional view, taken on the line 6 6 of Figure 4.

Figure '7 is a sectional view similar to that illustrated in Figure 4 showing the relief valve boss at the forward end of the engine, and

Figure 8-is a sectional view, taken on the line 8 8 of Figure 7.

Referringy to the accompanying drawings, I

have used the reference numeral i0 to indicate the cylinder block casting of a twelve-cylinder V-type motor. An oil pan Il is secured to the underside of the cylinder block I0 and a crankshaft l2 is rotatably mounted in the cylinder block in the conventional manner. A cam shaft I3 is driven through timing gears 32' from the crankshaft l2, and an oil pump drive pinion i4 is formed on the other end of the cam shaft which is in mesh with 50 an idler gear l5 which latter gear meshes with a pump drive gear i6. The gear i6 issecured to the upper end of a pump shaft. l'l which shaft extends downwardly through a pump housing 20 into the oil pan il Oil pump gears I8 are driven 55 by the shaft i? so that upon normal rotation of (Cl. 12S-196) the engine oil will be drawn from the pan I l and forced up through a sleeve-.shaped chamber I9 which is formed in the pump housing 20 around the shaft Il. A pressure relief valve 2| is provided in the housing 20, which valve is adjusted 5 to remain closed under oil pressures of less than pounds per square inch delivered by the pump. The chamber I9 is connected with a drilled opening 22 which extends upwardly therefrom to the upper portion of the cylinder block where it in- 10 tersec'ts a horizontal drilled opening 23. The opening 23 is connected with a main oil distributing pipe 24 which extends lengthwise in the V of the cylinder block. Suitable drilled openings 25 extend from the pipe 24 to the crankshaft and cam l5 shaft bearings of the engine so that oil under pressures up to 45 pounds per square inch is delivered to the various bearing surfaces of the engine. In the claims, these bearing surfaces are designated for convenience as primary bearing 20 surfaces.

A pipe 26 is connected with the vertical opening 22 and a tube 2l extends from the pipe 26 to an oil filter 28. A return tube 29 leads from the filter back to the cylinder block where it is connected 25 to a horizontally drilled opening, shown by dotted lines 30 in Figure 2. A restricting orifice 3i is interposed in the tube 29, this orice having a clear diameter of %4". This orifice is so small that only a minor portion of the oil circulated by 30 the pump gears i8 will flow through the oil purier. The major portion of the oil flows directly from the opening 22' to the main distributing oil pipe 2li.

It will be noted from the drawings that hy- 35 draulic valve tappets 33 are reciprocally mounted in the conventional manner within the V of the engine. The inner ends of the tappets bear upon the cam shaft i3. Each of these tappcts is provided wlth an oil reservoir 36 therein and a cylin- 40 der 35 is fixed in the reservoir 34 within the tappets 33. A piston 36 is reciprocally mounted within each cylinder 35 and a compression spring 3l at alltimes resiliently urges the piston 36 upwardly against the bottom of engine valves 33. The spring 31 is not suiiiciently strong to force the valve off its seat but simply takes up the clearance between the piston and the foot of the valve. The valves are held in place by conventional valve springs 53. A ball-type check valve 39 is inserted in the bottom of the cylinder 35 so that as the piston 36 is raised upwardly, oil will be drawn through the check valve 39 into the space beneath the piston 36.` The check valve 39 prevents the 55 discharge of oil from the cylinder 35 so that when the cam' shaft reciprocatesthe tappets, the valves will likewise be reciprocated.

It will be noted that a groove 40 is formed around the center portion of each tappet 33, and an opening 4I permits'oil to iiow into the resetvoir 34 to keep same filled and replenish the oil which may leak around the piston.

The valve tappets, just described, are generally referred to as hydraulic tappets and no claim is.

made hereinto any novelty in the tappet per se. This invention relates solely to means for supplying oil under all conditions to operate the tappets rather than to the tappet construction.

In order to supply oil to allof the tappets I provide a pair of horizontally extending drilled passageways 42 in the cylinder block l0, which passageways'iextend through the centers of the respective rows of tappet `receiving openings. One of the passageways 42 is connected to the opening 30 shown by dotted line so that oil from the filter is supplied directly to one of the passageways. Figure 3 shows that at the rear end of thecrankcase a boss 44 is cast on the cylinder block having a chamber 45 formed in its upper end. A port 46 connects the chamber 45 with the main oil pipe 24 and a pair of drilled openings 41 connect the chamber 45 with .the passageways 42, respectively. A ball-type pressure relief valve assembly 48 is inserted into the upper end of the port 46, which relief valve is adjusted so as to open at a pressure of 30 pounds per square inch. This pressure is substantially less than that required to open the relief valve 2l. A cap 49, is secured over the chamber 45.

It will also be noted that a boss 50, similar in shape to the boss 44, is cast on the cylinder block l at the forward end thereof, and that a pressure relief valve l is screwed ldown into this boss. Openings 52 connect the relief valve 5I with the passageways 42. The relief valve 5I is set to open at 20 pounds pressure per square inch. The plunger of the valve 5I has a fiatted portion 43 thereon so that a small amount of oil will at all times flow past the valve onto the timing gears 32. When the valve opens, all of the oil discharged therethrough will flow over the timing ears. g From the foregoing, it will be seen that oil is forced by the pump 20 under a maximum of 45 pounds pressure to the main oil pipe 24, the overiiow discharging back to the oil pan. At idling speeds the oil pressure is, of course, considerably less. A portion of the oil delivered by the pump is conducted to the oil purifier 28, the amount being regulated by the V54" orifice 3l'. Oil from the purifier 28 flows through the tube 29 to the passageways 42, but the pressure in the passaget ways is limited to a maximum of 20 pounds by the relief valve 5|. Consequently, there is a normal pressure differential of 25 pounds between the main oil pipe 24 and the tappet supply passageways 42. The relief valve 48 is adjusted to open at 30 pounds so that the valve will remain closed under these conditions. However, should the purifier 28"become clogged up to the extent that it will not supply oil under at least 150 pounds normal pressure, then the pressure diiierential between the passageways 42 and main oilpipe 24 will be increased to 30 pounds at which time the valve 48 will open to allow oil to flow directly from the pipe 24 to the valve tappets. This condition will continue until the oil purifier has been cleaned, at which time the preferred system of operation will automatically come into play.

y The principal advantage of this construction is that only filtered oil will be supplied to the tappets because a small particle of grit might very readily bind one of the tappet pistons and prevent the tappetV spring from returning the piston outwardly. This would cause a noisy tappet and reduce the valve opening. However, where only filtered oil is provided, failure of the cleaner may cause all of the tappets to fail, thus reducing the valve lift and causing the valve heads to pound against the valve seats instead of being uniformly decelerated to their closed positions.

Only with the above described construction have these two results been obtainable in one engine.

Some changes may be made in the arrangement, construction and combination of the various parts of my improved device without departing from Vthe spirit of my invention and it is my intention to cover by my claims such changes as may reasonably be included within the scope thereof.

1 I claim as my invention:

1. An engine having principal and secondary bearing surfaces therein, said principal bearing surfaces being lubricated by oil directly from the engine oil pump while said secondary bearing surfaces are normally lubricated by cleaner oil comprising, an oil pump driven by said engine, main oil lines conducting oil from said pump under a'substantial pressure directly to said principal bearings, an oil purifier associated with said engine and connected to said main oil line so that oil from said pump is forced through said purifier, a passageway conducting the clean oil from said purifier to said secondary bearing surfaces, a port disposed between said main oil line and said passageway, and a valve disposed in said port which normally remains closed and which upon the stoppage of oil from said purifier while the engine is running, opens to supply oil to said secondary bearing surfaces directly from said main oil line.

2. An engine having principal and secondary bearing surfaces therein, said Iprincipal bearing surfaces being lubricated by oil directly from the pump of said engine while said secondary bearing surfaces are normally lubricated by cleaner oil, comprising, an oil pump driven =by said engine, said pump having a pressure relief valve yassociated therewith, a main oil line conducting oil under a substantial pressure from said pump to the said principal bearing surfaces, an oil purier associated with said engine and connected to said main oil line so that oil from said pump is forced through said purifier, a Vpassageway having a restricting orifice therein conducting the clean oil from said purifier to said secondary bearing surfaces, a second relief valve associated with said passageway, said secondary valve being adjusted to maintain the oil in said passageway at a pressure less than that in said main oil line, a port connecting said main oil line and said passageway, and a third relief valve disposed in said port which is adjusted to open at a pressure intermediate of that of said first and second-mentioned relief valves, for the purpose described.

3. An engine having hydraulically operated valve tappets therein comprising, an oil pump driven by said engine, a main oil line conducting oil from said pump to the lprincipal bearings of said engine, an oil purifier associated with said engine and connected -to said main oil line so that the oil from said pump is forced through said purifier, supply means for conducting clean oil from said purifier to the valve tappets of said engine, a port between said main oil line and said valve tappet supplying means, and a valve disposed in said port which normally remains closed `and which upon the stoppage of oil from said driven by said engine, a main oil line conducting oi-l under an appreciable pressure from said pump to the principal bearings of said engine, an oil purier associated with said engine and connected to said main oil line so that oil from said pump is forced through said purifier, supply means conducting the clean oil from said purifier.

to said valve tappets, a restricting orifice in said supply means, a port extending lbetween said main oil line and said valve tappets, and a relief valve disposed in said port which normally remains closed and which upon the stoppage of oil from said purifier while the engine is running opens to supply oil to said tappets directly from said main oil line.

5. An engine having hydraulically operated valve tappets therein comprising, an oil pump driven by said engine, said pump having a pressure relief valve associated therewith, .a main oil line conducting oil under a substantial pressure from said pump to the principal bearings of said engine, an oil purifier associated with said engine, a conduit conducting oil from said main oil line through said purifier, a passageway conducting oil from said purifier tosaid Valve tappets, said passageway having a restricting orifice therein said passageway having a pressure relief Valve associated therewith whereby the oil pressure beyond said orifice is maintained at a substantially lower pressure than in said main oil line, a port disposed between said main oil line and said passageway, and a third relief disposed in said port which upon .the maintenance of the norm-al pressure differential between said mainoilline andsaid passageway remains closed and which upon a material increase in said pressure differential opens to supply oil to said tappets directly from said main oil line.

6. An engine having hydraulically operated valve tappets therein comprising, an oil pump driven by said engine, said pump having a pressure relief valve associated therewith which is adjusted :to open only at a pressure of substantially pounds per square inch, a main oil line conducting oil from said pump to the principal bearings of said engine, an oil purier associated with said engine, a conduit connecting said main oil line with said purifier, a passageway conducting clean oil from said purier to said valve tap.- pets saidv passageway having a restricting orice therein between said tappets and said purier, a second relief valve lconnected to said passageway whereby the pressure upon said tappets is maintained at substantially 20 pounds pressure per square inch, a pont disposed between said main oil line and said tappets, and a third relief valve disposed in said port which is adjusted to openA at substantially 30 pounds pressure per square inch so that said third valve normally remains closed and upon the reduction of oil pressure in said tappet passageway below 10 pounds pressure per square inch opens to supply oil .t-o said tappets directly from said main oil line.

7. An engine having rtiming gears and hydraulically operated valve tappets therein comprising, an oil pump driven by said engine, said pump havinga pressure relief valve associated therewith, a main oil line conducting oil under a substantial pressure from said pump to the main Abearings of said engine, an oil purifier associated with said engine, a pipe conducting oil from said main oil line to said cil purifier, a passageway supplying oil from said purifier to said valve tappets said passageway having a restrictingorice therein adjacent to said purifier, a second mentioned relief valve connected with said passageway, said relief valve being adjusted to open at a pressure materially less than that at which said pump relief valve is adjusted, the discharged oil from said second mentioned relief valve being -deposited upon said timing gears to lubricate same, a port disposed between said main oil line and said passageway, and a third relief valve disposed in said port, which last-mentioned valve is adjusted to open at a pressure between that at which the rst two-mentioned reilef valves are adjusted to open, for the purpose described.

FRANK JOHNSON.

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