US 3647024 A
An arrangement for lubricating the upper bearing for a drive shaft in a marine propulsion unit. A disc-shaped member, which may be a gear used to drive a propeller, is situated below the upper bearing in the bore of a gearcase. Lubrication oil is supplied to the gearcase. There is a small clearance between the bore of the gearcase and the outside diameter of the disc-shaped member to prevent rapid leakage of oil from around the periphery of the disc-shaped member. The disc-shaped member when rotating acts as a centrifugal impeller throwing oil out from its center and up a passageway to the upper bearing. The lubricating oil spills over the upper bearing and returns to the gearcase by way of a drive shaft passage to provide a continuous lubricating means.
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Description (OCR text may contain errors)
United States Patent 1131 3,647,024
Wick et al. 1 Mar. 7, 1972 1541 UPPER DRIVESHAFT BEARING 1,915,330 6/1933 LUBRICATION FOR MARINE 1 936 111 11/1933 PROPULSION UNIT 234401338 4/1948 2,458,813 1/1949  Inventors: Gerald H. Wick, Menomonee Falls; 6, 1950 Theodore J. lloltermann, Milwaukee, both of Wis. Primary ExaminerManuel A. Antonakas Attorney-Robert K. Gerling, Robert E. Clemency, John W.  ASSgnee: outboard Mame C(lrpomuon, Michael, Gerrit D. Foster, Bayard'l'l. Michael, Paul R. Puerkegan nir, Joseph A. Gemignoni and Andrew 0. Riteris  Filed: Apr. 30, 1970  App1.No.: 33,832
1  ABSTRACT An arrangement for lubricating the upper bearing for a drive shaft in a marine propulsion unit. A disc-shaped member,
 US. Cl. ..184/6.l8,184/6.12, 123/196 W, which may be a gear used to drive a propeller, is situated 308/ 1 34.] below the upper bearing in the bore of a gearcase. Lubrication  lnt.Cl ..F16n 7/16 oil is supplied to the gearcase. There is a small clearance  Field of Search ..184/6.18, 6.28, 6.12; between h r f th gearc e n the utside diameter of 123 19 w; 303 134 415 10, 11 2 2 the disc-shaped member to prevent rapid leakage of oil from around the periphery of the disc-shaped member. The disc-  References Cited shaped member when rotating acts as a centrifugal impeller throwIng oIl out from Its center and up a passageway to the UNITED STATES PATENTS upper bearing. The lubricating oil spills over the upper bearing and returns to the gearcase by way of a drive shaft passage to 18.13115?!" ..184/6.l8 provide a continuous lubricating means. 1 l 1,062,876 5/1913 Blymyer ..415/ 122 6 Claims, 2 Drawing Figures ,l /|6 i I lz e is :i 1 f 56 t l2 IO 1 I 1 lfl'l'ili 32 PATENTEDMAR 7 I972 INVENTORS THEODORE J. HOLTERMANN GERALD H.'WlCK UPPER DRIVESI-IAF'I BEARING LUBRICATION FOR MARINE PROPULSION UNIT BACKGROUND OF INVENTION The invention relates generally to marine propulsion devices, such as outboard motors and stern drive units,'and more particularly to lower units therefor. The lower unit of a marine propulsion device is normally at least .partially in water and is conventionally vertically tiltable and horizontally swingable to afford steering. Such marine propulsion devices or units commonly include a substantially upright drive shaft which is supported by upper and lower bearings mounted in a drive shaft housing. The drive shaft drives a propeller shaft through a gearing arrangement normally mounted in a gearcase which is connected to the bottom of the drive shafthousing. More particularly, the invention relates to supplying lubrication to the upper bearing located in spaced relation above the bottom of the drive shaft housing.
SUMMARY OF INVENTION The invention relates to an arrangement for lubricating an upper drive shaft bearing in a marine propulsion unit.
, A primary object of the invention is an improved means for transferring lubricating oil to an upper gearcase bearing in a marine propulsion unit.
A further object is a novel apparatus that acts as a centrifu- THE DRAWINGS The invention is illustrated by the accompanying drawings wherein:
FIG. 1 is a partial section view of the lower unit of a marine propulsion unit; and
FIG. 2 is an enlarged view of a disc-shaped member inaccordance with the invention.
DETAILED DESCRIPTION Referring to the drawings in more detail, it will be seen that FIG. 1 shows a lower unit of a marine propulsion unit. The marine propulsion unit may be either-an outboard motor or a stern drive engine which is supported for vertical tilting and horizontal swinging as is well known in the art. The lower unit 10 includes a drive shaft housing 12 connected to, or integral with, a gearcase 14.
The drive shaft housing 12 includes a drive shaft 16 operably connected to a suitable source ofpower, such as the engine or motor. The drive shaft 16 ismounted'in an interior cavity 18 of the housing 12 and turns in an upper bearing 20 and a lower bearing 22. A cap'24, which may be part of the lower half of a water pump, retains the upper bearing 20in position. In addition, it should be noted that the upper bearing 20 is shown as ball bearings while the lower bearing 22 is shown as'needle bearings, however, any type of bearings'may be used as long as they provide adequate support and allow the necessary rotating movement of the drive shaft 16.
The interior cavity 18 of the drive shaft housing preferably communicates with a bore 26' in the gearcase I4. The bore 26 holds a sufficient quantity of lubricating oil 28 which may be supplied through an aperture with a plug, not shown. The aperture may be located in the drive shaft housing 12 for easy access.
As shown in FIG. 1, the drive shaft 16 engages a propeller shaft 30 through a gearing arrangement to drive a propeller LII 32. The gearing arrangement includes a pinion 34 mounted on the lower end of the drive shaft 16 engaging a forward bevel gear 36 and a reverse bevel gear 38, both mounted on the propeller shaft 30. The propeller shaft may be mounted for rotation in bushings 40 and 41 at the forward end, and in a bearing 42 atthe aft end of the gearcase. Another bearing-44 supports the gear 38for rotation on the propeller shaft. The gears 34, 36 and 38 are always in mesh with eachother and the lubricating oil 28 is continuously circulatedto the upper bearing 20 except at extremely low speeds when the pressure developed is too low to raise the oil the required distance.
The shaft mechanism is.not shown but maybe any conventional type such as an electrically actuated hydraulic power shift using gearcase oil to apply the forcerequired for shifting action, or an electric powered shift using an electromagnetic coil. As shown in'FIG. l, the forward bevel gear 36 and the reverse bevelgear 38 rotateindependently of the propeller shaft 30 unless a clutch dog 46 is engaged by the shift mechanism.
In accordance with the invention, FIG. 1 shows the reverse bevel gear 38 having at least one axial transfer opening 48. The openings '48 may be drilled through the gear and areprovided to permit movement of the lubricatingoil 28 between the forward and rearward portions of the gearcase 14.
At least one radial feed hole 50 leads from a center open portion 52 of the gear 38 to a groove 54 in the periphery of the gear. Two radial feed holes each having a diameter of approximately three thirty-seconds of an inch have been found to adequately supply lubricating oil to the periphery of the gear. The rotating gear 38 acts as a centrifugal impeller throwing lubricating oil out from the center of the gear up the radial feed hole 50 to the groove 54.
The groove 54 isformed by a pair of outer circumferencial edges or rims 56 which have a small clearance with the bore 26 of the gearcase 14. It has been foundthat a clearance ranging from 0.0015 to 0.0035 inch works well for the invention. This small clearance between the edges 56 and the bore 26 limits the leakage of lubricating oil from the groove 54. The lubricating oil in the groove 54 is thus pressurized and made to travel up an oil passageway 58'formed in the drive shaft housing 12.
The oil passageway 58 may be approximately the same diameter as the radial feed holes 50. The oil passageway 58 leads to the upper bearing 20 thus allowing the lubricating oil 28 to spill over the bearing and return to the gearcase 14 by way of the interior cavity 18in the drive shaft housing. In taking this path the returning oil also lubricates the lower bearing 22.
FIG. 2 shows the bevel gear 38 and various features of this inventionin more'detail. The plurality of radial feed holes 50 supply the lubricating oil 28 to the periphery of the gear 38. The oil rotates in the peripheralgroove'54 and-builds-up pressure as the rotational speed of the gear'increases. When the peripheral speed reaches approximately 250 feet per minute or greater, sufficient pressure is built up to-push the oil'up the passageway 58 leading to the upper bearing 20. It has been found that a passageway approximately 5 inches long works well with the dimensions and speeds given herein. In addition it has been found that'the lubricating'an'angemcnt works well when thelubricating oil 28 in the gearcase l4 fills-the bore 26 to a level which'reaches to the top-of the center open portion 52, as shown in FIG. I.
In use the pinion 34 of thedrive shaft engages and rotates the bevel gears 36 and 38. The lubricating oil 28 is forced up the passageway 58 to the upper bearing 20 by centrifugal force. The oil 'spills over the upper bearing 20 and returns to the gearcase 14 through the interior cavity 18 of the drive shaft housing. Thus, a continuous supply of lubricating oil is provided for the upper bearing 20.
The axial transfer openings 48, radial feed holes 50, peripheral groove 54 and other features have been shown and described'as located in the-reverse bevel gear 38. It is important to note that these features may be located in either or both bevel gears 36 and 38, or instead, may be incorporated in a separate disc-shaped member. in addition, it should be pointed out that the groove 54 may be formed or cast in the drive shaft housing 12 instead of being formed by the rims 56 in the gear 38.
Various features of the invention are set forth in the following claims.
What is claimed is:
1. A marine propulsion unit comprising a drive shaft housing, a drive shaft rotatably mounted in said housing, an upper bearing in said housing and supporting said drive shaft, a gearcase connected with said drive shaft housing below said bearing and adapted to contain a quantity of lubricating oil, a propeller shaft rotatably mounted in said gearcase and driven by said drive shaft, an oil passageway independent of said drive shaft and extending from said gearcase to said upper bearing, and a disc-shaped member rotatably mounted in said gearcase for movement through the oil contained therein and driven by said drive shaft, said disc-shaped member including a feedline extending radially in said disc-shaped member and terminating, at its radially outer end, in position for periodic communication with said oil passageway in response to rotation of said disc-shaped member and adapted, at its radially inner end, for communication with the oil in said gearcase.
2. A marine propulsion unit as set forth in claim 1 wherein said drive shaft housing has an interior cavity formed around said drive shaft and communicating with said gearcase to allow the lubricating oil to be continuously circulated by spilling over said upper bearing and returning to said gearcase through said interior cavity.
3. A marine propulsion unit as set forth in claim 1 wherein said disc-shaped member has at least one axial transfer opening permitting movement of lubricating oil through said diseshaped member.
4. A marine propulsion unit as set forth in claim 1 wherein said disc-shaped member includes a periphery having therein means defining a peripheral groove communicating with said feedline and with said oil passageway.
5. A marine propulsion unit as set forth in claim 1 wherein said gearcase includes a bore communicating with said oil passageway, and wherein said periphery of said disc-shaped member includes a pair of axially spaced circumferential edges having a small clearance with said gearcase bore, and wherein said feedline terminates between said edges.
6. A marine propulsion unit as set forth in claim 1 including a pinion gear on the lower end of said drive shaft and wherein said disc-shaped member is a part of a bevel gear driven by said pinion gear.