US2570898A - Nonfreezing oil system - Google Patents

Description

Oct. 9, H WQQD NQNFREEZING OIL SYSTEM Filed April 2, 1948 INVENTOR. e/flWood,

be seriously damaged within a short time.

Patented Oct. 9, 1 951 NGNFREEZIN OIL SYSTEM Roger H. Wood, Tomah, Wis.

Application April 2, 1948', Serial No. 18,588

1 Claim. (Cl. 184-6) The present invention relates to an improved non-freezing oil system which has particular application to the lubricating-systems of internal combustion engines.

In all internal combustion engines there is a tendency for water to gradually accumulate within the crank case during the interval between oil changes, "and this accumulation can 'become quite substantial under certain driving conditions, particularly with lealry piston rings, long intervals between'oil changes, etc.- In calities which are subject to rather cold winters the freezing of this accumulation of water within the crank case can create pronounced lubrication difiiculties. The accumulation of water remains below the oil, and ifthisaccumulation is of suiiicient quantity to extend up to or slightly above the lower end of the oil line, the freezing of the water at this point can totally block the oil line. This fact is rendered particularly hazardous, because the water collects in a place where the operator of the vehicle cannot observe it and therefore cannot know what the current water level is, but can only know whatthe water level is after the oil system has become frozen and the motor is being operated without oil. Moreover, if he should not be watching his oil gauge closely he would not be aware of the condition even then. If the engine is operated with the oil line thus blocked bytruck drivers, filling station operators, etc. is to' direct the flame of a blow torch against the under side oi the oil pan of the car, truck or'tractor. This is a diflicult, hazardous operation which must be repeated every morning or after every interval when the engine stands idle for sometime in cold weather. 7

My invention avoids these diflficulties by provviding an improved safety by-pass in association with the conventional suction inlet pipe which supplies oil from the sump or lower levelof the crank case to the oil pump. "This safety (by-pass is normallyclosed or does not normally pass oil from the crank case sump'to'the oil Freezing of the inlet end of the safety by-pass :is prevented by a unique construction and warrangement wherein the safety by-pass draws from a non-freezing level which is disposed between the lower suction level of the suction inlet pipe and the top liquid level of the oil standing at the normal or average oil level in the crank case. This nonfreezing level is main tained non-freezing by virtue of a sufiicient differential above the lower suction level and by virtue of the fact that the accumulation of water within the crank case is prevented from rising appreciably above this lower suction level because of the inherent vaporization of the water in different parts of the engine and of the crank case when sucked up into the lubricating system. This will be explained more fully in the followingdetailed description of several preferred embodiments of the invention. In the accompanying'drawings illustrating such embodiments:

Figure 1 is a fragmentary, sectional View through the crank case and lower portion of an internai'combustion engine illustrating the application of my invention thereto.

Figure 2- is .a fragmentary, vertical, sectional .view through one embodiment of the invention.

Figure 3 is a side view of this type of embodiment, also illustrating an inverted cup attached to the suction inlet pipe for the oil pump and showing the oil drain plug with an attached through still another embodiment.

Figure 1 is illustrative of any conventional design of internal "combustion engine comprising a crankshaft l6 mounted in main bearings ll and having operative connection through connecting rods i2 with pistons reciprocating in the engine cylinders. The conventional crank case is indicated at the lower part of which defines an ,oil-Sump l6 containing the lubricating oil H.

a The-crank case is usually provided with a remov- "pump. However, if the normal flow through the V suction inlet pipe is blocked by ice, then the safety by-pass automatically opens'or automatiically permits oil flow therethrough inashunt .around the frozen end of the suction inlet line.

ableoil pan, as is well known.

'iiie lubricating system of engine is sup- In the typical constructhe oil sump. Directly below this inverted cup 2|, the crank case or pan is provided with a drain opening 23 which is normally closed by the removable plug 24, the latter having threaded mounting in the drain opening. A straining screen 26 of cylindrical form extends upwardly from the drain plug 24 into the inverted cup 2| to a point near to the under side of the closed upper end of the cup. Thus, the oil passing to the pump through suction inlet pipe I9 is normally strained through the screen 26, but if the screen should become clogged with sludge, then the oil is sucked up over the top of the screen and then into the inlet pipe.

Referring first to the embodiments illustrated in Figures 2 and 3, the suction inlet pipe I9 extends downwardly within the inverted cu 2| and is formed with a flared lower end 28 defining the suction opening I9. This suction opening I9 is located at a relatively low level in the crank case and lower than the level of the rim of the inverted cup. The safety by-pass of my invention is shown in the form of a syphon tube 3| in the embodiments illustrated in Figures 2 and 3. This syphon tube has its lower intake opening 3| disposed at a substantially higher level than the intake opening I9 of the main suction inlet pipe I9. From this higher intake opening 3| the tube 3| extends upwardly and then curves downwardly to define an inverted U or syphon bend 32. The downwardly extending leg of the syphon bend opens into the suction inlet pipe I9 through the lateral port 33.

If desired, the syphon bend may be curved over a sloping portion of the inlet pipe I9, as shown in Figure 2, and this syphon bend is preferably located above the cup (Figure 3) so that it will have a substantial height above the inlet opening 3|. An air pocket 34 will form in the bend or bulge 32 for controlling the syphon flow through the safety by-pass 3 I.

Referring now to the operation of the embodiments as shown in Figures 2 and 3, attention is first directed to the four liquid levels designated AA, BB, C-C and D-D. Level A-A diagrammatically represents the surface level of the body of oil I I when the oil stands at a normal or average level corresponding to a normal or average sunply of oil in the crank case. The intermediate level BB indicates that level from which the syphon tube 3| will draw when the safety by-pass is in operation by reason of an ice blocked condition of the suction inlet pipe I9. The level CC aproximately indicates a water level substantially coincident with or slightly above the level of the intake opening I9, which water level would be adequate to freeze the inlet opening I9 shut. Level D-D is approximately shown as being slightly below suction opening I9, and indicates approximately a typical water level in the crank case during the time that the engine is running. A substantial accumulation of water can collect quite ripidly in the crank case of an internal combustion engine, largely from the products of combustion leaking past the piston rings and condensing in the crank case. Let us assume that this accumulation of water has reached approximately the level C-C substantially coincident with or slightly above the suction inlet opening I9. When the engine is started the' suction inlet pipe I9 first draws water to the lubricating system, this continuing until the water engine is approximately indicated at DD. Because the suction opening cannot draw water below this level DD, it follows that the quantity of water represented by the level DD will remain substantially permanently in the crank case until the crank case is drained in the operation of changing oil. If two much water collects in the crank case, it is sucked up and sent through the motor, with the result that much of it is vaporized and leaves the crank case through the breather. When the engine has stopped running a residual accumulation of water in diiferent parts of the engine tends to flow back to the bottom of the crank case. This running accumulation of water in the engine includes water entrained in the oil, and water vapor in the crank casewhich condenses when the engine stops, and also other droplets of water adhering to the sides of the crank case, etc. With the return of this running accumulation of water to the bottom of the crank case, the water level is quite likely to be brought up to the suction inlet immersion level indicated approximately at CC Then, if a protracted spe l of extremely cold Weather occurs, this water freezes across the inlet opening I9 and totally blocks oil flow through this opening when the engine is again started. As a result of this blocked condition at the opening I9, a relatively large suction is established in the suction inlet pipe I9, with the result that oil is drawn up through the by-pass inlet 3| and over the syphon bend 32 and through port 33 into the suction inlet pipe, as indicated by the directional arrows. The accumulation of water does not reach up to the intermediate level BB and hence there is no ice blocking the bypass inlet 3|. Thus, oil is supplied immediately to the motor through this safety by-pass, and such supply continues during the running of the motor until the crank case has become sufficiently warm to melt the ice blocking the main inlet opening I 9, whereupon the oil flow through the by-pass 3| is interrupted and the oil flow through the inlet opening I9 is resumed. From the above-described operation, it will be seen that the main suction inlet I9 exerts a controlling influence upon the water level in the bottom of the crank case, tending to confine this water level substantially between the two levels indicated at C-C and DD, so that the water level is never allowed to reach up to the point BB where it might freeze shut the by-pass inlet 3|. In this same regard, it is also important that the by-pass inlet 3| be entirely'independent of the main inlet I9, so that it does not have to draw its supply of oil through the same inlet opening or at the same inlet level that constitutes the normal or main supply. When the ice in the inlet opening I9 thaws out and flow through this opening resumes, the by-pass flow through tube 3| automatically stops because the air pocket 34 in the syphon bulge 32 prevents the oil from syphoning over the hump. It will be seen that the distance which the oil has to be raised above the normal surface level AA, in order to lift it over the hump at 32, is substantially greater than in the case of oil lifted directly from this level AA to the level of the port 33. Hence,

' no fiow occurs through the by-pass when normal level drops to a oint just enough below the inlet 7 flow can occur through the main suction opening I 9'.

Referring now to the modified embodiment of the invention shown in Figures 4 and 5, in this construction the safety by-pass comprises a small check valve housing 35 which is secured to or formed integral with the side wall of the suction inlet pipe 19 at a point adjacent the upper end of the entrance funnel 28. The open lower end 35 of this housing 35 constitutes the by-pass inlet opening adapted to draw oil from the intermediate oil level BB. A necked or tapered bushing 36 extends upwardly within the housing 35 to form a valve seat 6'! for the ball check valve 38. The chamber area above the valve seat 37 opens laterally into the suction inlet pipe i9 through registering openings 36 and 40 in the housing and in the pipe. Under normal operating conditions the check valve 38 seats on the valve port 31, since there is an insufiicient suction differential acting upon the ball to lift it from its seat. However, as soon as the main suction opening l9 has become closed or sufficiently constricted by ice to create a substantial suction within the suction inlet pipe 19, the check valve 38 thereupon lifts off its seat and permits a bypass flow of oil through Toy-pass opening 35 and through registering ports 39 and es into the pipe l9. The by-p-ass action of this embodiment will be understood from the detailed description of the preceding embodiment.

In Figures 4 and 5 I have shown a supplementary feature which may be employed, if desired. This consists of a narrow notch 42 cut through the bottom portion of the suction inlet pipe or funnel at one side thereof adjacent to the bypass inlet. This slot is of benefit because it permits some oil to flow through the upper part of the slot when the lower part of the slot is closed or constricted by ice. The slot is also beneficial in that it enables oil to flow through the regular suction inlet, more promptly after the oil has started to warm up than if such slot is not included. Such arrangement of slot may also be provided in the embodiments shown in Figures 2 and 3, preferably with the slot at one side adjacent to the by-pass inlet opening 3|.

In Figure 6 I have illustrated still another embodiment of my invention wherein the safety bypass flow occurs through a spring-closed suctionresponsive valve, preferably mounted in the funnel 28 or other adjacent portion of the suction inlet pipe I9. This valve designated 45 opens inwardly from a valve port 46 formed in the side of the funnel 28. A stem 41 extends outwardly from the valve and passes through a spider 48 provided in the valve opening 46 and through an angle-shaped guide bracket 49. A compression spring 51 on the valve stem acts between the spider 45 in its closed position. The lower part of this valve and its port are disposed at a nonfreezing intermediate level BB above the levels susceptible to freezing. Hence, in the event that the suction inlet opening l9 becomes closed or substantially constricted by ice, this safety bypass valve 45 remains free to open to permit oil to flow to the pump until the motor has become sufiiciently warm to thaw out the ice in the opening 19', whereupon normal flow is resumed through this opening and the valve 45 closes. The operation of this embodiment will be clearly understood from the operation of the embodiments shown in Figures 2 and 3.

With regard to situations where the straining screen at the inlet end of the oil pipe might become plugged up by sludge alone, or by ice alone, or by both, the invention can be adapted to those situations in different ways. For example, the top of the straining screen 26 can terminate slightly below the under side of the closed upper end of the cup 2!, so that if the screen should become plugged up by sludge the oil can still flow over the top of the screen and reach the suction opening :9. Another way is to have the syphon tube 3| of Figures 2 and 3 extend down on the outside of the screen 26 and of the cup 2|, in which case the lower rim of the cup 2! must extend down to a level equal to that of the oil pipe suction inlet and lower than that of the syphon tube 3!. In this latter arrangement with the syphon tube 3! disposed on the outer side of the cup 2|, the upper end of said syphon tube could also be arranged to empty into the upper portion of the cup, in which case the lower rim of the cup would have to extend down to a lower level than the regular oil pipe I9 and also to a lower level than the syphon tube 3|. In this arrangement the lower end of the regular oil pipe I9 preferably has one or more relatively deep notches 42 in its lower end and also preferably does not extend down to a level much lower than half way from the level of the rim of the cup to the closed upper end of same where it is attached to the regular oil pipe.

While I have illustrated and described what I regard to be the preferred embodiments of my invention, nevertheless it will be understood that such are merely exemplary and that numerous modifications and rearrangements may be made therein without departing from the essence of the invention.

I claim:

In an internal combustion engine comprising a crank case adapted to contain oil and an oil pump adapted to pump oil therefrom through the lubricating system of the engine, the combination therewith of a suction inlet for the oil pump having a low-level suction opening normally drawing oil or water from a relatively low level in said crank case, and a syphon tube safety by-pass having an inlet opening disposed above said low-level suction opening for drawing oil from an intermediate level when said low-level opening is blocked by ice, the discharge end of said syphon tube discharging into said suction inlet pipe.

ROGER I-I. WOOD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,399,943 Dunham Dec. 13, 1921 1,568,796 Breer Jan. 5, 1926 1,648,910 Cooper Sept. 18, 1928 1,874,976 Hans Aug. 30, 1932 2,285,997 Mino June 9, 1942 2,372,286 Mieras Mar. 27, 1945

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