US2669322A - Splash type lubricating device for single cylinder horizontal internal-combustion engines - Google Patents

Description

Feb.'16; 1954 H. s. BROWN SPLASH TYPE LUBRICATING DEVICE FOR 2 SINGLE CYLINDER HORIZONTAL INTERNAL-COMBUSTION ENGINES Filed June 30, 1952 2 Sheeps-Sheet 1 Feb. 16, 1954 H. s. BROWN 2,669,322

SPLASH TYPE LUBRICATING NGLE CYLINDER HORIZONTAL INT ENGINES Filed June 50, 1952 DEVICE FOR SI L ERNA WNW

'Hugh www Patented Feb. 16, 1954 UNITED Vsrl-'iiT135 N T OFFICE SPLASH TYPE .LUBRICATING DEVICE,- FR SINGLE lCYLINDER HORIZONTAL vINTER- NAL-COMBUSTION ENGINES :Briggs- & Stratton Corporation,

Milwaukee,

, 6 Claims.

'I'his invention relates-to splash type lubricating devices lfor internal combustion engines and refers more particularly toa device` for the linternal -lubrication of small single cylinder horizontal engines in which the crankshaftis disposed-on a vertical axis. The vertical disposition of -their crankshaftsadapts these engines fto many uses not Atoo wellserved by the more 'conventional upright` engines, rotary power lawn mowers for instance. But in suchr horizontal engines-the crankcase itself" must be specially. designed to prevent the supply of linternal-lubrieating oil leaking out through `the lower crankshaft bearing, especially when the engine is idle.

Moreover unless vthe bottom ofthe crankcase is-disposed well below lthe cylinder, the oil-level in the'crankcase wouldl oftenvbe above the `mouth of '.the cylinder, and oil v would then ,seepy through the piston rings and, of courseyfoulftlie engine. It is, therefore, necessary, in an engine' having avertical crankshaft, to provide-anoilsump so disposed that the level of the oilthereinlzisialways spaced below the vtop of the. lowermostf crankshaft bearing and, of course, lwell below;the cylinder. ABut this places the-oil in the sump beyond the,V reach of the moving engine parts `within the crankcase and .introduces the rproblem of feeding the oil to the cylinder Wall and `the crankshaft bearings. While a pump could-be used .for this. purpose, the added expense entailed thereby practically rules it outas a solution tothe problem.

It is, therefore, an object of this invention-to provide a simple inexpensive device whichy ,has none of the disadvantages of a pump, but instead operates upon the time tested. splash. principle, forlubricating the moving .parts inside the ,crankcase ofan engine of the type having a vertically disposed crankshaft.

v.Morespecifically it is an object ofnthis invention 4Ato provide a unitary oil slinger member rotatably mounted within the engine `with a portion thereof dipping into the oil bath anddriven from the engine timing gears so as tothrowil out of the sump-and onto the moving engine, parts during operation ofthe engine.

` With the above and other objects in view, which. will appear as the`description proceeds, this invention resides in the novel construction, .com-

bination and arrangement of parts substantially as hereinafter described and more particularly den'ed bythe appended claims, it being understood that such changes in the precise embodiment' tof the hereindisclosed` yinvention maybe made ascome vwithin the scope oftheclaims *The accompanying drawings illustrate two complete -f examples'of the physical embodiments ofthe invention constructed according 'to 'the bestfmod'es Aso far devised for the practicalapplication of the principles thereof, andin'which:

Figure l is an elevational view of a single cylind'erfgasoline engine embodying the lubricating deviceof this invention, a portion of the crankcase'fand oil sump being broken away to better illustrate the lubricating device itself;

Figure* 2A is an enlarged sectional View of aportion of the engine, said view corresponding'substantially to that portion of the engine in the area shown broken away'in Figure 1;

Figure 3 is a bottom view of theoil slinger member per-se;

Figure 4 is a side view of a horizontal engine ofdifferentdesign from that vshown in Figure 1, illustrating the application of this invention theretoyparts of said View being broken away and in section and on the plane of the line 4 4 in Figure-5;

Figure 5 isa horizontal sectional view through Figure 4-on the plane of the line 5 5; and

vFigure 6 yis a detail sectional view taken through Figure 5 onthe plane of the-line 6 6.

' rReferring nowmore particularly to the accompanying' drawings lin which like numerals designate like parts throughout the severalv views, and'fespecially to Sheet 1 thereof, the numeral 5 designates `generally a smally single cylinder internalcombustion engine of the type having a cylinder -Gat one side of -a crankcase l, the axis ofthecylinder being horizontal, and having a crankshaft' 8 mounted on a vertical axis.

'Inside thecrankcase, as is conventional,- are a vnumber of moving parts which are in need of lubricationV at all times during operation of the engine, including the lower crankshaft main bearing: 9;"the `upper crankshaft. bearing il), the connecting'rod bearing Il, as well as the cylinder wall and ther wrist pin bearings "(not shown). TheA crankshaft projects from the crankcase at botliits upper and 'lower ends, its upper endportionvhaving a starterxpulley 'i2xsecured thereto and' its lowerendportion I3 being' connectible with'a device tobe'drivenl by the motor.

vThe-lower wall I4 of the crankcase has a lboss [5in which the lower ,main` bearing 9 is press fitted anclwhich carries an oil seal l'beneath the' bearing. An annular space I'l aroundL thev crankshaft; between the lower main bearing and the oil seal, is communicated'with the interior of thecrankcasethrough an upwardly opening well liinithe" boss. T'The slighthead of oilv which accumulates in this well I8 and the space I1 is beneficial in easing the friction at the heavily loaded lower main bearing during starting and before a fresh supply of oil is brought to the bearing through its oil hole I9.

The supply of lubricating oil for the engine is held in a sump 2G, formed as part of a substantially L-shaped shell 2l which is bolted to the crankcase by screws 22 and closes what would be the bottom of the crankcase ina vertical or upright engine. A gasket 25 between the crankcase and the sump shell seals the connection between the two; and a drain plug 26, at the bottom of the outer side wall of the sump, enables the oil to be drained therefrom.

Oil from the sump is thrown onto the moving engine parts inside the crankcase by means of the novel lubricating device of this invention, which in the Figure l embodiment comprises a unitary disc-like slinger member 21 and an intermediate gear 2t, which drives the slinger member and is in turn driven by a gear 29 on the crankshaft. The gear 29 is just above the main bearing and may be one of the timing gears of the engine.

Both the oil slinger and the intermediate gear are best molded of plastic, preferably nylon. The slinger comprises a hub portion 30 having a bore 3i therethrough to provide a bearing by means of which the slinger may be mounted, a frusto-conical medial portion 32 having gear teeth 33 on its cuter conical face, and a flat rim-like outer portion 34 having three paddlelike projections 35 thereon which dip into the oil in the sump and throw it onto the moving engine parts in the interior of the crankcase as the slinger rotates.

The slinger is freely rotatably mounted on a bearing structure, indicated generally by the numeral 36, which projects into the sump from a boss 31 on the side wall of the sump adjacent to the crankcase proper, with its axis disposed at an acute angle to the crankshaft axis so that the lower side of the slinger periphery is adjacent to the bottom of the sump, and the opposite side of its periphery is closer to the crankshaft. The gear teeth 33 are on the bottom face of the slinger, i. e., the surface which faces the crankshaft.

The intermediate gear 28, like the slinger member, has a bored hub 4 l and is mounted on a vertical bearing structure, designated generally by the numeral 42, which projects up into the crankcase from a boss 43 on the bottom crankcase wall, between the crankshaft and the slinger, so that the driving gear has its axis parallel to that of the crankshaft and meshes with the gear 29 on the crankshaft and with the gear teeth 33 on the bottom of the slinger.

The bearing structures by which the intermediate gear and the slinger are mounted include bored plugs ld which are press fitted into accurately bored apertures in the bosses Ii3 and 31 in the bottom crankcase wall and the inner sump wall, respectively. Each plug has a stub shaft l1 secured thereto by a screw 46, upon which the hubs of the slinger and gear are drectly journalled, the thrust bearings being provided by the adjacent ends of the plugs and heads 48 on the stub shafts. The employment of the plugs 4t eliminates the necessity for facing operations on the crankcase and sump shell castings, and thus facilitates manufacture of those parts.

It will be seen that the orbit of the paddleon the underside of the slinger member is such that, as the slinger rotates, the projections dip into the oil in the sump, passing near to the bottom thereof so that the slinger will operate satisfactorily when the oil level in the sump is low, and then move upwardly toward the crankshaft, passing part way into the interior of the crankcase itself. In the course of this orbit the projections throw oil onto the moving parts in the interior of the crankcase between and including the lower and upper crankshaft bearings 9 and Hl, respectively, distributing oil substantially uniformly over all of them. After circulating over` the parts, the oil of course returns to the sump by gravity.

The modified embodiment of the invention illustrated in Figures fi, 5 and 6 diners from that described principally in the way in which the sump for the lubricating oil is provided and the Way in which the slinger is driven. Thus, the oil sump instead of being provided by an L-shaped shell bolted to what normally is the bottom of the crankcase is formed by a cover plate 4S bolted to and closing what, in a vertical engine, is the side of the crankcase.

This cover plate t9 not only provides the base 5l) by which the engine is mounted in a horizontal position with its crankshaft axis vertical, but also has the lower main crankshaft bearing 5i and one of the cam shaft bearings 52 therein. 'lo preclude the drainage of lubricant from the oil reservoir provided by the interior of the cover plate il@ the bearings 5l and 52 are located in upstanding bosses 53 and fait, respectively, the tops of which are well above the normal oil level.

The slinger 55 by which the oil is lifted from the sump or reservoir and thrown upwardly against the moving engine parts, as in the previously described embodiment of the invention, is mounted to rotate about an inclined axis so as to facilitate geared driving connection between the slinger and one of the timing gears 56, the bottom of the slinger being provided with gear teeth 51 for this purpose.

Attention is directed to the fact that no intermediate gear is necessary in this embodiment of the invention. The specic construction of the mounting for the slinger is also slightlyT different in this form of the invention and consists merely of a tubular stub shaft tt bolted to an upstanding boss 59 which forms an integral part of the cover plate L39 and on which the slinger is freely journalled.

From the foregoing description taken in connection with the accompanying drawings, it will be readily apparent to those skilled in this art that this invention provides a simple inexpensive means of reliably lubricating the moving parts of a small gasoline engine which, because of its being mounted with its crankshaft axis vertical cannot employ the customary splash system of oiling wherein the crankshaft itself or some means on the connecting rod dips down into the oil bath to throw the oil up onto the moving parts; and that it entirely eliminates the problem of loss of lubricant through the bottom main bearing of such horizontal engines.

What I claim as my invention is:

1. In an internal combustion engine having a vertical crankshaft journalled in axially aligned top and bottom bearings, a crankcase and a horizontal cylinder at one side of the crankshaft: means defining an oil sump in open communication with the interior of the crankcase and havlike projections ing a portion thereof near the bottom bearing of the crankshaft; a rotatable oil slinger; means rotatably mounting the slinger with its axis disposed at an acute angle to an axis parallel to that of the crankshaft and with part of the slinger disposed in that portion of the oil sump near the bottom bearing and extending beneath the normal oil level; and a geared driving connection between the crankshaft and said rotatable slinger, so that the slinger rotates during operation of the engine and acts to throw oil from the sump upwardly into the crankcase interior to lubricate the moving engine parts therein.

2.v In an internal combustion engine having a vertical crankshaft, a crankcase, axially aligned top and bottom bearings in which the crankshaft is journalled, and a horizontal cylinder at one side of the crankshaft: means defining an oil sump in open communication with the interior of the crankcase, said oil sump having its bottom on a level below that of the bottom bearing; a rotatable oil slinger; means rotatably mounting said oil slinger with its axis disposed at an acute angle to an axis parallel to that of the crankshaft and at that side of the crankshaft opposite the cylinder and with the lower portion of the slinger contiguous to the bottom of the oil sump so as to dip down into the oil contained therein, the angular disposition of the slinger positioning the same so that the oil flung upwardly thereby as the slinger rotates is thrown up into the interior of the crankcase and against the moving engine parts therein; and a driving connection between the crankshaft and said rotatable slinger through which the slinger is rotated during operation of the engine.

3. In an internal combustion engine, the structure set forth in claim 2 further characterized by the fact that the driving connection between the crankshaft and the slinger comprises one of the timing gears of the engine, and gear teeth on the underside of the slinger meshing with said timing gear.

4. In an internal combustion engine of the horizontal type having a crankshaft and a cam shaft rotating on vertical axes, top and bottom bearings in which the crankshaft and cam shaft are journalled, a crankcase and a horizontally disposed cylinder at one side of the crankshaft: a removable pan-like cover plate closing the bottom of the crankcase and defining an oil sump in open communication with the interior of the crankcase; upstanding bosses rising from the bottom of said cover plate in which the lower bearings for the crankshaft and ea-m shaft are mounted, the top of said bosses being a substantial distance above the bottom of said sump so as to be above the normal oil level; timing gears on the crankshaft and cam shaft directly above the tops of said bosses; a rotatable oil slinger; means rotatably mounting the slinger with its axis at an angle to the axis of one of said shafts and at the side thereof opposite the cylinder 6 and with the lower portion of the rotatable slinger contiguous to the bottom of the oil sump and its upper portion contiguous to the timing gear on said shaft; and gear teeth on the slinger meshing with said timing gear so that during operation of the engine the slinger rotates to lift oil from the sump and throw it upwardly into the interior of the crankcase.

5. In an internal combustion engine having a vertical crankshaft, a crankcase and a horizontal cylinder at one side of the crankcase: means defining an oil sump in open communication with the interior of the crankcase, said oil sump having its bottom spaced a substantial distance below the cylinder; a rotatable oil slinger having a plurality of vane-like projections thereon; means rotatably mounting said oil slinger at the side of the crankshaft opposite the cylinder with the axis of the slinger disposed at an acute angle to that of the crankshaft and with one side of the orbit of said projections adjacent to the bottom of the sump and the opposite side of said orbit closer to the axis of the crankshaft and projecting partway into the crankcase and pointing towards the cylinder so that upon rotation of the slinger oil is thrown from the sump into the crankcase interior toward the cylinder to lubricate the moving engine parts therein; and a driving connection between the slinger and the crankshaft.

5. In an internal combustion engine of the type having a crankcase, a crankshaft rotatable on a vertical axis in main bearings mounted in the walls of the crankcase, and an oil seal between the crankcase and the crankshaft beneath the lowermost main bearing to prevent leakage of oil out of the interior of the crankcase: means defining an oil sump at one side of the crankcase in open communication with the interior of the crankcase and having its bottom below the level of said oil seal, so that oil tends to drain from the crankcase into said sump, thereby preventing oil leakage out of the crankcase when the engine is idle; a disc-like rotatable oil slinger having a plurality of paddle-like projections spaced from its axis; means rotatably mounting said oil slinger with its axis disposed at an acute angle to that of the crankshaft and with one side of the orbit of said projections adjacent to the bottom of said sump and the opposite side of said orbit closer to the axis of the crankshaft; gear teeth on the surface of said oil slinger which faces the crankshaft; and a gear rotatably driven by the crankshaft and meshing with the gear teeth on said oil slinger to rotate the slinger during operation lof the engine and thus cause the projections thereon to throw oil from the sump into the crankcase interior to lubricate the moving parts therein.

HUGH S. BROWN.

References Cited in the file of this patent UNITED STATES PATENTS

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