US3678879A

US3678879A - Inboard-outboard drive for watercraft

Info

Publication number: US3678879A
Application number: US116963A
Authority: US
Inventors: Yoshiro Morimoto
Original assignee: Nissan Motor Co Ltd
Current assignee: Nissan Motor Co Ltd
Priority date: 1970-02-24
Filing date: 1971-02-19
Publication date: 1972-07-25
Anticipated expiration: 1989-07-25
Also published as: GB1303953A; CA931828A; JPS4947794B1; SE361636B; FR2078958A5

Abstract

A propulsion unit for an inboard-outboard drive of a watercraft having a power source mounted therein which propulsion unit includes a horizontal drive shaft operatively connected to the power source, a vertical drive shaft, a first gear means connecting the vertical drive shaft to the horizontal drive shaft, a horizontal propeller shaft provided with a propeller, a second gear means connecting the propeller shaft to the vertical drive shaft and a universal joint carried by one of the two horizontal shafts and having a center lying on the axis of the vertical drive shaft. The propulsion unit further includes housing means which is disposed outboard of the watercraft and enclosing movable parts, the housing means including a first housing member and a second housing member one of which is associated with the universal joint to be freely rotatable about the axis of the vertical drive shaft for thereby steering the watercraft, and the first housing member supporting at one end said first gear means and at the other end said second gear means whereby a reaction torque produced by the gear means is absorbed by said first casing member.

Description

United States Patent Morimoto 51 July 25, 1972 INBOARD-OUTBOARD DRIVE FOR WATERCRAFT [72] Inventor: Yoshiro Morimoto, Fujisawa, Japan [73] Assignee: Nissan Motor Company, Limited,

, Yokohama, Japan [22] Filed: Feb. 19, 1971 [21] Appl.No.: 116,963

[30] Foreign Application Priority Data Feb. 24, 1970 Japan ..45/l5756 [52] U.S.Cl ..115/35 [51] 1nt.Cl. ..B63h1/04,B63h25/42 [58] FieldofSearch ..ll5/35,4l;74/417,607,l5, 74/69 [56] References Cited UNITED STATES PATENTS 2,532,470 12/1950 Wanzer ..ll5/35 2,880,689 4/1959 Bokowski 3,521,589 7/1970 Kemp 3,376,842 4/1968 Wynne ..ll5/35 Primary Examiner-Milton Buchler Assistant Examiner-Gregory W. O'Connor Attorney-John Lezdey [57] ABSTRACT A propulsion unit for an inboard-outboard drive of a watercraft having a power source mounted therein which propulsion unit includes a horizontal drive shaft operatively connected to the power source, a vertical drive shaft, a first gear means connecting the vertical drive shaft to the horizontal drive shaft, a horizontal propeller shaft provided with a propeller, a second gear means connecting the propeller shaft to the vertical drive shaft and a universal joint carried by one of the two horizontal shafts and having a center lying on the axis of the vertical drive shaft. The propulsion unit further includes housing means which is disposed outboard of the watercraft and enclosing movable parts, the housing means including a first housing member and a second housing member one of which is associated with the universal joint to be freely rotatable about the axis of the vertical drive shaft for thereby steering the watercraft, and the first housing member supporting at one end said first gear means and at the other end said second gear means whereby a reaction torque produced by the gear means is absorbed by said first casing member.

4 Claims, 4 Drawing Figures I9 I I6 I017 I g 57 r 2 27b [5 Patented Jul 25, 1972 BEST AVAILABLE COPY 3,678,879

2 Sheets-Sheet l 39 in; i

3 (@02 \P-i'I IIIUQEEi 3 44 42 32 INVENTOR YOSH/RO MOR BY 12 0 to ATTORN Patented July 25, 1972 I BEST Amman: copy 3,678,879

2 Sheets-Sheet .J

v INVENTOR Y SHI'RO MOK/MOTO g AT I 032m! INBOARD-OUTBOARD DRIVE FOR WATERCRAFT This invention relates to an improved inboard-outboard drive for watercraft. A propulsion unit of an inboard-outboard drive is commonly mounted on the stern transom of the watercraft and driven by a prime mover mounted inboard of the watercraft. In such a drive, provision is made for rotatably supporting the propulsion unit for steering on a generally vertical axis. Commonly, the propulsion unit is also rotatable or can be tilted on a generally horizontal axis to clear an underwater obstruction. It is generally an object of this invention to provide an improved inboard-outboard drive which includes provision for both steering and tilting.

According to this invention, there is provided a propulsion unit for a watercraft which propulsion unit comprises a horizontal drive shaft operatively connected to the prime mover, a vertical drive shaft, first gear means connecting the vertical drive shaft to the horizontal drive shaft, a horizontal propeller shaft, second gear means connecting the propeller shaft to the vertical drive shaft and a universal joint carried by one of the two horizontal shafts and having its center point lying on the axis of the vertical drive shaft. The propulsion unit further includes housing means which is disposed outboard of said watercraft and enclosing movable parts, the housing means including a first housing member and a second housing member one of which is associated with the universal joint to be freely rotatable about the axis of the vertical drive shaft for thereby steering the watercraft, and the first housing member supporting at one end said first gear means and at the other end said second gear means whereby a reaction torque developed by said gear means is absorbed by said first casing member.

IN THE DRAWINGS:

FIG. 1 is a partially sectioned side elevation of an inboardoutboard drive according to this invention;

FIG. 2 is a partial top plan view of the inboard-outboard drive of FIG. 1;

FIG. 3 is an enlarged perspective view of a portion of a steering arrangement to be incorporated into the inboard-outboard drive shown in FIG. 1; and

FIG. 4 is a plane view ofthe embodiment shown in FIG. 1.

Referring to FIG. 1, there is shown a propulsion unit for an inboard-outboard drive of a watercraft. The propulsion unit comprises a horizontal drive shaft supported for rotation within a pair of bearings 11 and 12 which are mounted on a bracket 13 rigidly secured to a transom 14 of watercraft which is designated at 15. The horizontal drive shaft 10 is drivably connected through a fly-wheel 16 to a power source (not shown) mounted inboard of the watercraft 15. At 'an intermediate point of its length the horizontal drive shaft 10 is provided with a universaljoint 17, through the center of which extends the generally horizontal tilt axis of a propulsion unit generally designated by 18, as will be more fully described hereinafter. The universal joint 17 is preferably of a synchromesh type but may be replaced by a Cardan joint. The rear end of the horizontal drive shaft 10 extends into a gear casing 19 forming a part of a housing means, which will be described in detail hereinafter. The propulsion unit further comprises a first gear means which is shown to include a drive gear 20 carried on the horizontal drive shaft 10 and a pair of vertically spaced bevel gears 21 and 22 meshing with the drive gear one of which is a forward gear and the other a reverse gear. The bevel gears 21 and 22 are supported for free rotation within bearings 23 and 24 on the upper end of a vertical drive shaft 25. Thus, rotation of the drive gear 20 causes rotations of the bevel gears 21 and 22 in opposed directions. A clutch element 26 disposed between the bevel gears 21 and 22 is carried by the vertical drive shaft and is slidable axially thereon to selectively engage the bevel gears 21 and 22 to complete the drive connection between the horizontal and vertical drive As seen from FIG. 1, the propulsion unit also comprises a housing means 27 which is disposed outboard of the watercraft 15. The housing means is supported by a plate member to be discussed in detail in the generally horizontal tilt axis to accommodate tilt movements of the propulsion unit. The housing means includes a first housing member 27a and a second housing member 27b, one of which is associated with a universal joint, as will be described in detail, to be freely rotatable about the axis of the vertical drive shaft 25 for thereby steering the watercraft. The first housing member 27a includes a cylindrical housing portion (not identified) which supports the vertical drive shaft 25. As shown in FIG. 1, the first housing member 27a is constructed to support, in addition to the first gear means, a second gear means so that a reaction torque developed by the rotation of the propelleris absorbed by the first housing member 27a. The second gear means includes a bevel gear 29 supported through a bearing 28 at the lower portion of the cylindrical housing portion of the first housing member 27a and a bevel gear 30 which is carried on a horizontal propeller shaft 31. The horizontal propeller shaft 31 is shown to comprise first and second shaft portions 31a and 31b. The first shaft portion 310 is supported for rotation within a bearing 32 mounted in the lower portion of the first housing member 270 while the second shaft portion 31b is supported by the second housing member 27b.

The second housing member 2712 also includes a cylindrical portion which is rotatably supported by the cylindrical housing portion of the first housing member 270 on a generally vertical axis corresponding to the vertical drive shaft axis 25 for steering control of the propulsion unit 18. A pair of vertical spaced

bearings

35 and 36 are mounted within the cylindrical portion of the first housing member 27a to provide for free rotation of the second housing member 27b relative to the first housing member 27a. At the upper end of the second housing member 27b a seal 37 is provided to prevent water from entering the interior of the second housing member 27b through a clearance 38 between the coaxially disposed cylindrical portions of the

housings

27a and 27b. The second housing member 27b includes a rearwardly extending cylindrical portion 39 in which a pair of horizontally spaced bearings 40 and 41 are mounted to rotatably support the second shaft portion 31b of the horizontal propeller shaft 31. A seal 42 is also provided at the outer end of the rearwardly extending cylindrical portion 39 to exclude water from the interior of the propulsion unit housing 33. In the embodiment shown in FIG. 1, the universal joint, designated at 43 is positioned at an intermediate point of the horizontal propeller shaft 31 so that the center of the universal joint 43 lies on the extension of the axis of the vertical drive shaft 25. This universal joint 43 also is preferably of a synchromesh type but may be substituted by a Cardan joint. A suitable propeller 44 is carried on the horizontal propeller shaft 31 and is driven by the vertical drive shaft 25 through the universal joint 43 and the

bevel gears

29 and 30. A rubber blade 45 is shown to be secured to the second housing member 27b 33 for rotation therewith about the axis of the vertical drive shaft 25.

The gear casing 19 is provided on its top with a lug 46 having an eyehole 47 in which a tilt control cable 48 is anchored at its one end. The control cable 48 is wound on a pulley 49 which is rotatably supported on the transom of the watercraft 15. As seen in FlGs. l and 4, a plate 50 carried on the gear casing 19 has a forwardly extending arm 51 mounted to the lowermost portion thereof as at 52. The arm 51 is formed at the fore end thereof with a notch 53 which is engageable on a pin 54. The pin 54 is mounted in one or another of openings 55 arranged in a rearwardly extending portion 56 of the mounting bracket 13, permitting adjustment of the relative angles between the transom 14 and the generally vertical steering axis. Tilting of the propulsion unit 18 may occur upon meeting an obstruction with sufficient force to cause the arm 51 to disengage from the pin 54. It will be noted that the notch 53 is so shaped as to provide a cam action to raise the arm 51 when the second housing member 27b is urged away from the transom 14. The second housing member arm 51 and rotating the pulley 49 so as to roll the control cable 48 therearound.

Another plate 57 is also carried on the second housing member 27b so as to rotate therewith about the cylindrical portion of the first housing member 27a The plate 57 is provided at the top thereof with an upwardly extending rod 58 which bends forwardly at its end to form a horizontal portion 59. As is best seen in FIG. 2, the horizontal portion 59 of the upwardly extending rod 58 has an eyehole 60 therein for movably receiving the lower end of a lever 61 which is mounted to a generally horizontal steering shaft 62 for pivotal movement about a pin 63. The steering shaft 62 is supported by suitable means (not shown) for rotation about its axis. Steering is accomplished by manually rotating the steering shaft 62 in a clockwise encounter-clockwise direction to cause the lever 61 to swing, thereby rotating the propulsion unit 18 about the axis of the vertical drive shaft 25. It will be understood that due to the pivotal connection between the lever 61 and the steering shaft 62 tilting movements of the propulsion unit 18 will not disturb the steering geometry of the unit.

A modified form of the propulsion unit is schematically illustrated in FIG. 3, wherein like component parts are designated by same numerals except that a prime has been added thereto. In this embodiment the drive connections between the horizontal drive shaft 10' and the vertical drive shaft 25' and between the vertical drive shaft 25' and the horizontal propeller shaft 31' are mounted within a first housing member 27'a which in turn is rotatably supported by the casing a second housing member 27'b. The horizontal drive shaft 10 is shown to include first and second shaft portions 10'a and 10'b between which a universal joint 43' is disposed in such a manner that a center therefore intersects the extension of the axis of the vertical drive shaft 25. A reversing device 66 comprising a planetary gear system is provided at an intermediate portion of the horizontal drive shaft 10' in place of the reversing device comprising a pair of bevel gears 21 and 22 and the clutch 26 shown in FIG. 1.

It will now be appreciated that since a plurality of drive connections including gear' means are supported by a unitary housing member, a reaction torque produced by the gear means is absorbed thereby and, therefore, a propulsion unit can be mounted on the watercraft at the center thereof.

What is claimed is:

1. A propulsion unit for an inboard-outboard drive of a watercraft having a prime mover mounted within said watercraft, comprising a horizontal drive shaft operatively con nected to said power source and extending rearwardly of said watercraft, a vertical drive shaft, first gear means disposed between said horizontal and vertical drive shafts for establishing drive connection therebetween, a horizontal propeller shaft provided with a propeller for driving said watercraft, second gear means disposed between said vertical drive shaft and said propeller shaft for establishing drive connection therebetween, a universal joint carried by one of said two horizontal shafts and having its center point lying on the axis of said vertical drive shaft, and housing means disposed outboard of said watercraft and enclosing said shafts, third gear means and universal joint, said housing means including a first housing member and a second housing member one of which being associated with said universal joint so as to be freely rotatable about the axis of said vertical drive shaft for steering said watercraft, and said first housing member supporting at one end said first gear means and at the other end said second gear means whereby a reaction torque developed by propeller rotation is absorbed by said first housing member.

2. A propulsion unit according to claim 1, wherein said first and second housing members respectively include cylindrical portions each extending along the axis of said vertical drive shaft, said cylindrical portion of said second housing member being disposed on the cylindrical portion of said first housing member, whereby said second housing member is freely rotatable about the cylindrical portion of said first housing member.

3. A propulsion unit according to claim 2, wherein said propeller shaft includes first and second shaft portions supported by said first and second housing members, respectively, said first and second shaft portions being connected with each other through said universal joint having its center point lying on the axis of said vertical drive shaft, and said first housing member being operatively connected to said watercraft, whereby said second housing member is freely rotatable about the axis of said vertical drive shaft in association with said universal joint.

4. A propulsion unit according to claim 1, wherein said propeller shaft is supported by said first housing member and said horizontal drive shaft includes first and second shaft portions which are supported by said first and second housing members, respectively, said second housing member being operatively connected to said watercraft, and said first and second shaft portions being connected with each other through said universal joint having its center point lying on the

Claims

1. A propulsion unit for an inboard-outboard drive of a watercraft having a prime mover mounted within said watercraft, comprising a horizontal drive shaft operatively connected to said power source and extending rearwardly of said watercraft, a vertical drive shaft, first gear means disposed between said horizontal and vertical drive shafts for establishing drive connection therebetween, a horizontal propeller shaft provided with a propeller for driving said watercraft, second gear means disposed between said vertical drive shaft and said propeller shaft for establishing drive connection therebetween, a universal joint carried by one of said two horizontal shafts and having its center point lying on the axis of said vertical drive shaft, and housing means disposed outboard of said watercraft and enclosing said shafts, third gear means and universal joint, said housing means including a first housing member and a second housing member one of which being associated with said universal joint so as to be freely rotatable about the axis of said vertical drive shaft for steering said watercraft, and said first housing member supporting at one end said first gear means and at the other end said second gear means whereby a reaction torque developed by propeller rotation is absorbed by said first housing member.

4. A propulsion unit according to claim 1, wherein said propeller shaft is supported by said first housing member and said horizontal drive shaft includes first and second shaft portions which are supported by said first and second housing members, respectively, said second housing member being operatively connected to said watercraft, and said first and second shaft portions being connected with each other through said universal joint having its center point lying on the axis of said vertical drive shaft, whereby said first housing member is freely rotatable about the axis of said vertical drive shaft in association with said universal joint.