US2496434A

US2496434A - Outboard motor lubricating system

Info

Publication number: US2496434A
Application number: US558560A
Authority: US
Inventors: Alfred S Bosma
Original assignee: Hart Carter Co
Current assignee: Hart Carter Co
Priority date: 1944-10-13
Filing date: 1944-10-13
Publication date: 1950-02-07
Anticipated expiration: 1967-02-07

Description

Feb T75, T195@ A. s. BosMA OUTBOARD MOTOR LUBRICATING SYSTEM 2 sheets-sheet 1 Filed OCT.. l', 1944 at E 0J 5 INVENTOR.

ATTORNEYS.

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'Feba 7 E950 A. s, BQSMA 2,496,434

ouTBoARD MOTOR LUBRICATlNG SYSTEM Filed oct. 15, 1944 A2 shets-sneet 2 gygy '5,

5 f INVENTOR EN i @gli/i3 Patented Feb. 7, 1950 UNITED STATES Pi'iTillNT OFFICE OUTBOARD IMOTOR LUBRICATING SYSTEM Alfred yS. Bosma, New Holstein, Wis., assignor to Hart-Carter Company, Peoria, Ill., a corporation of Delaware Application AOctober 13, 1944, Serial No. 558,560

koil in iva separate reservoir haslheretofore presented problems in an outboard motor. One of said problems arises Afrom the lfact that 4an outboard motoris `frequently tilted to a horizontal lposition While on a boat or while being manually carried or placed on its side while being transported in a vehicle. Another problem :is that of leakage of oil during operation.

My patent,No. -2,458,051,issued January 1, 1949, shows -a desirable .form of four cycle outboard motor construction having a separate oil reservoir `and :which is `designed to overcome the 'abovementioned problems.

It is, therefore, one of the objects of the present yinvention to provide `an improved four cycle outboard motor construction v-having a separate oil reservoir and oil feeding means, said reservoir being so located and constructed with reference to the position of cooper-ating 'parts that fthe motor may be tilted to Vall necessary positions or placed on its rside without causing oil from the reservoir to enter the cylinder and start trouble, and said 4reservoir being so located that surplus oil will drain from the vvbearings back into the reservoir vdur-ing normal operation.

A further object of the invention is to provide vin a construction as above described, improved means preferably including agear pump for leffectively feeding the o-il to the parts to Ybe lubricated.

Amorespecic object of the invention is to provide an outboard motor construction wherein a housing -for the vertical drive shaft is so shaped and yconstructed as to form `a reservoir for oil, there being means for delivering oil from the reservoir to the crankcase and `for 'draining surplus oil from the crankcase back into the reservoir. The drain'arrangement is so worked 'out in conjunction with the housing forming the reservoir that the motor may be tilted to a horizontal position while on the boat 'or while being manually carried, or the `motor may be placed on vits :side 'or even inverted without permitting oil Vfrom the reservoir to Aenter the crankcase. The arrangement is such that the gear pump, which 4is employed for forcing the oil upwardly to the crankcase, may be located in a position Where itis normally submerged in oil, Thus Vpriming of the gear pump is unnecessary.

A further object of the invention is to 'provide a construction as above described wherein the oil reservoir is so located that the oil therein serves to lubricate the lower bearing for the rvertical drive shaft, the bottom bevel gears, and the bearings Afor the horizontal propeller shaft. It is, therefore, unnecessary with this motor to utilize a special grease for lubricating the bottom vgealli C2156.

A further object of the Ainvention is to provide an outboard motor construction, as vabove described, wherein the oil reservoir is immersed in water during normal use to cool the oil and render operation of the engine moreeilicient.

A -still further object of the invention is to provide an outboard motor constructiomas above descbribed, wherein there is a special seal adjacent the propeller which effectively prevents leakage of oil or entrance of water into the bottom .propeller yshaft housing.

With the above and other objects in View, the invention consists of the improved outboard motor, and all its parts and combinations as set forth in the claims, and all equivalents thereof.

In the accompanying drawings, illustrating one complete -embodiment of the preferred form of the invention,

Fig. 1 Lis a vertical longitudinal sectional View through the improved motor;

Fig. l2 is a fragmentary vertical sectional view taken at right angles to Fig. y1;

Fig. 3 is a sectional View taken approximately on the line 3--3 of Fig. 1, on a larger scale, parts being broken away;

Fig, 4 is a sectional View taken on the line 4-4 of Fig, 1; and

Fig. 5 is a fragmentary sectional View taken on line 5 5 of Fig. 4.

Referring more particularly to the drawings, the power head is designated generally by the numeral 8 and includes an upper housing portion 9 and a lower housing lportion l0. The lower housing portion `ID forms the bottom for the crankcase 5.

There is also a vertical drive shaft housing designated by the numeral l I which comprises an upper lpart l2 and a lower part I3.

Bolts I4 secure the bottom housing i0 for the power head in position and also secure the upper part l2 of the vertical drive shaft housing in assembled relationship, there being a bearing plate l5 in between the members 10 and H.

The vertical drive shaft housing parts I2 'and I3 are suitably connected with a horizontal plate or n I6 therebetween, there being gaskets I1 and I8 at the joint. The fm I 6 serves as an anticavitation plate.

Within the power head 8 is a four cycle gasoline engine and in the preferred embodiment the engine comprises two cylinders I9 and 20. There may, however, be a greater or a lesser number of cylinders. The cylinder I9 is equipped with two valves 2 I, one being an intake valve and the other being an exhaust valve, and the cylinder 20 is similarly equipped with two valves 22. 'I'he ignition is provided by spark plugs 23 and 24.

Within the cylinders I9 and 20 are

pistons

25 and 26 which are suitably connected in the usual manner by connecting rods 21 with the crankshaft 28. The upper end of the crankshaft projects through a bearing 29 at the top of the head and carries a y wheel 3D. The lower end of the crankshaft is suitably journalled in a ball bearing assembly 3| received in a cup shaped portion of the housing portion I8. Below the ball bearing assembly is an oil seal 32. Suitably splined to the lower end of the crankshaft is a vertical drive shaft 33 which has its upper end portion rotatable in a bearing 34 supported in the bearing plate I5. Below the bearing 34 is an oil seal 35. A starting pulley 36 is suitably associated with the upper end portion of the vertical drive shaft 33.

The lower end of the vertical drive shaft 33 is journalled in a bearing 31, and below the bearing 31 the lower housing portion I3 is formed with a gear chamber 38. In this chamber is a bevel gear 39 rigidly connected to the lower end of the vertical drive shaft 33 and meshing with a bevel gear 40 rigidly connected to a horizontal propeller shaft 4I. The inner end of the propeller shaft is journalled in a bearing 42, and an intermediate proportion of said shaft is journalled in a bearing 43 suitably mounted in a boss 44. The boss 44 is connected by bolts 45 with the member I3 to close the gear chamber 38.

On the outer end of the horizontal propeller shaft 4I is the usual propeller 46. Adjacent the inner side of the propeller and surrounding the propeller shaft 4I within the boss 44 is a special seal. This seal comprises a brass disc 41, a cup shaped disc 48 preferably of a phenolic plastic material, and a packing 49 preferably of synthetic rubber. The various members forming the seal are held in effective position by a coil spring 50. This seal effectively prevents escape of oil from the chamber 38, as well as entrance of water to said chamber.

Suitably connected to the lower side of the horizontal fin I6 is a gear pump 5I. This gear pump is driven by the vertical drive shaft 33 and is adapted to pump oi1 from the housing portion I3, through an inlet tube 52, and deliver said oil under pressure upwardly through a tube 53 to the lower end of a bearing 54 for the cam shaft 55. As is clearly shown in Figs. l and 2, the bearing 54 is formed in a horizontal partition 58, and said partition has portions which slope toward an outlet opening 56 so that oil which drains from the crank case will be directed into the opening 56 and into a drain tube 51. The drain tube 51 extends downwardly to a point intermediate the length of the drive shaft housing and terminates in an open end 58. When the motor is in normal operating position the open end of the drain tube 58 is well above the normal level 59 of oil in the reservoir.

Oil delivered by the pump I through the delivery tube 53 enters a duct 60 in the cam shaft and flows upwardly through this duct to lubricate the top bearing BI for the cam shaft. The majority of the oil from the duct 60, however, is sprayed out of openings 62 in the cam shaft onto the connecting rod bearings.

The cam shaft is provided with a series of cams 63 for operating the intake and exhaust valves 2| and 22. Ihe cam shaft is driven by

gears

64 and 65, and the former is driven by the crankshaft.

The exhaust conduits from the motor are suitably connected to upper openings 66 of an exhaust tube 61, and the lower end of the exhaust tube is open, as at E8, to discharge below the water level.

A pin 69, which is supported on the exterior of the drive shaft housing II, extends through a pivot sleeve 10. Connected to the sleeve is the usual clamp 1I for removably securing the motor to a boat. The pin 69 is pivotal within the sleeve 10 to permit steering movement, and the entire motor is swingable on the pin 12 toward a horizontal inoperative position on the boat. In use of the device, the novel vhousing for the vertical drive shaft forms a reservoir for motor oil. This reservoir must be lled to approximately the level indicated at 59 in Fig. 1. When the motor is in normal operating position, oil in the reservoir will fiow downwardly through the openings 13 in the horizontal plate I6 into the reservoir portion 14 of the lower housing part I3 to fill the portion 14. Oil from the reservoir portion 14 will lubricate the bearing 31 and will also pass through one or more holes 15 into the gear chamber 38 to lubricate the bevel gears 39 and 40, as well as the bearings for the propeller shaft 4I. The special seal 41 will effectively prevent loss of any oil from the chamber 38 to the exterior.

The motor, of course, operates on gasoline undiluted with motor oil and during operation the gear'pump will be operated by the drive shaft 33. This will cause continuous pumping of oil from the lower chamber 14 upwardly through

tubes

52 and 53 into the cam shaft duct 60 to lubricate the motor. Surplus oil from the crankcase 1 will continually drain back into the oil servoir through the opening 56 and drain tube The vertical drive shaft housing I I is so shaped and is of such size, and the lower end 58 of the drain tube is so located, that when the motor is swung upwardly on the boat on the pivot 12 to an inoperative position, or when the motor is placed on either side, the oil in the oil reservoir will flow the length of the drive shaft housing portion II and the level will always be below the end 58 of the drain tube 51. Thus no oil can flow into the crankcase through the drain tube when the motor is in any one of thesehorizontally disposed positions.

Even 'if the motor is completely inverted, the oil in the reservoir will quickly fiow to the enlarged upper end portion of the drive shaft housing II and the open end 58 of the drain tube will be above the level of the oil while the motor is in inverted position.

With the particular arrangement above described, a four cycle engine may be successfully employed for an outboard motor without any inconvenience resulting from the oil which it is necessary to have in the oil reservoir. The gear pump 5I is advantageously located in a position where it is normally submerged in the oil, and this renders priming unnecessary. Furthermore, the lubrication of the bevel gears and propeller shaft bearings by the same oil which lubricates the engine itself, renders the use of a separate greasing arrangement at the lower end unnecessary. During use of the motor, the oil in the reservoir is always submerged in the water and is effectively cooled. This cooling of the oil is transmitted to the engine as the oil is used to lubricate the latter. As a result the engine is maintained at a cool running temperature to increase its efficiency of operation.

While the preferred embodiment includes the use of a four cycle engine, the features of `the present invention are suitable for use in connection with any engine in which oil is carried in a crankcase. Various other changes, modifications and adaptations may be made without departing from the spirit of the invention, and all of such changes are contemplated as may come within the scope of the claims.

What I claim is:

1. In an outboard motor having a top power head and including a combustion engine having a crankcase in said power head, a-bottom for said crankcase, a vertical drive shaft depending from said head and driven by said engine, an elongated vertical housing for said vertical drive shaft connected at its upper end -to the power head below the crankcase bottom, a portion of said housing which surrounds the lower part of the vertical drive shaft forming a reservoir for f motor oil when the motor is in normal operat- `ing position, means for delivering oil from said reservoir to said crankcase, and a return conduit for surplus oil from the crankcase having a discharge end located intermediate the length of the drive shaft housing and above the level of oil therein when the motor is in normal operating position.

2. In an outboard motor having a top power head and including a combustion engine having a crankcase in said power head, a bottom for said crankcase, a vertical drive shaft depending from said head and driven by said engine, an elongated vertical housing for said vertical drive shaft connected at its upper end to the power head below the crankcase bottom, a portion of said housing which surrounds the lower part of the vertical drive shaft forming a reservoir for motor oil when the motor is in normal operating position, means for delivering oil from said reservoir to said crankcase, and a return conduit for surplus oil from the crankcase having a discharge end located intermediate the length of the drive shaft housing and above the level of oil therein when the motor is in normal operating position, the drive shaft housing having a cross sectional area of such size and the discharge end of the return conduit being so located that there is space above the front wall of the housing sufficient to accommodate all oil normally in the crankcase at a level beneath the discharge end of the return conduit when the motor is swung .to an inoperative position on a boat.

3. In an outboard motor having a top power head and including a combustion engine having a crankcase in said power head, a bottom for said crankcase, a vertical drive shaft depending from said head and driven by said engine, an elongated vertical housing for said vertical drive shaft connected at its upper end to the power head below the crankcase bottom, a portion of said housing which surrounds the lower part of the vertical drive shaft forming a reservoir for motor oil when the motor is in normal operating position,

means for delivering oil from said reservoir to said crankcase, and a return conduit for surplus oil from the crankcase having a discharge end located intermediate the length of the drive shaft housing and above the level of oil therein when the motor is in normal operating position, there being sufficient space in the upper portion of the drive shaft housing above the discharge end of the return conduit to accommodate all oil normally in the crankcase when the motor is inverted, with said discharge end projecting above the oil level.

4. In an outboard motor having a top power head and including a combustion engine having a crankcase in said power head, a bottom for said crankcase, a vertical drive shaft depending from said head and driven by said engine, an elongated vertical housing for said Vertical drive shaft connected at its upper end to the power head below the crankcase bottom, a portion of said housing forming a reservoir for motor oil when the motor is in normal operating position, means for delivering oil from said reservoir to said crankcase, and an elongated return conduit for surplus oil from the crankcase having a discharge end located a substantial distance below the bottom of the crankcase and above the level of oil in the reservoir when the motor is in normal operating position.

5. In a normally vertically disposed outboard motor having a top power head and including a combustion engine having a crankcase in said head, a drive shaft housing below said crank case forming a reservoir for motor oil and having sidewalls, means for delivering oil from said reservoir to said crankcase for lubricating purposes and an elongated conduit extending into said housing for returning surplus oil from the crankcase to said reservoir, the outlet end of said conduit being located intermediate the length of said drive shaft housing and spaced from the sidewalls thereof 6. In a normally vertically disposed outboard motor having a top power head and including a combustion engine having a crankcase in said head, a drive shaft housing below said crankcase forming a reservoir for motor oil and having a forward wall portion and a rear wall portion, means for delivering oil from said reservoir to said crankcase for lubricating purposes, and an elongated conduit extending into said housing for returning surplus oil from the crankcase to said reservoir, the outlet end of said conduit being located intermediate the length of the drive shaft housing and positioned closer to the rear wall thereof than to the forward wall.

ALFRED S. BOSMA.

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

UNITED STATES PATENTS Number Name Date 1,446,775 Wahl Feb. 27, 1923 1,822,573 Fitzgerald Sept. 8, 1931 2,053,425 Else Sept. 8, 1936 2,289,124 Karey July 7, 1942 2,346,148 Bosma Apr. 11, 1944 FOREIGN PATENTS Number Country Date 432,035 Great Britain July 18, 1935