US3511460A

US3511460A - Manual tilting device for marine propulsion units

Info

Publication number: US3511460A
Application number: US685142A
Authority: US
Inventors: William J Shimanckas
Original assignee: Outboard Marine Corp
Current assignee: Outboard Marine Corp
Priority date: 1967-11-22
Filing date: 1967-11-22
Publication date: 1970-05-12
Anticipated expiration: 1987-05-12

Description

- May 12, 1970 x w. J. SHIMANCKASA 3,5

MANUALTILTING DEVICE FOR MARINE PROPULSION UNITS Filed Nov. 22, 1967 2 Sheets-Sheet 1 a? 4 ZZZ?! r g g k i? INVENTQR.

H V/aunm SH/Mfint'K/P! 1 E Y ArromvEY! MANUAL TIL-TING DEVICE FOR MARINE PROPULSION UNITS Filed Nov. 22, 1967 May 12, 19 170 v w. J. SHIMANCKAS 2 Sheets-Sheet 2 INVENTOR. W44 MMJ. S/l/Mfl/VCAA! Z2 Z3 Z8 0 BY MI A I M A from;

United States Patent 0.

3,511,460 MANUAL TILTING DEVICE FOR MARINE PROPULSION UNITS William J. Shimanckas, Waukegan, Ill., assignor to Outboard Marine Corporation, a corporation of Delaware Filed Nov. 22, 1967, Ser. No. 685,142 Int. Cl. B63h 21/26 U.S. Cl. 248-4 15 Claims ABSTRACT OF THE DISCLOSURE Disclosed herein is a manual tilting device for a marine propulsion unit, which device employs a hand crank to tilt the drive shaft housing about a horizontal tilt axis. The hand crank is connected to a band and pulley arrangement with each end of the band secured to separate pulleys rotatably supported by the stern bracket. The band is also reeved around a third idler pulley, mounted on an arm connected to a swivel bracket which is pivotally connected to the stern bracket to provide a horizontal tilt axis. Manual rotation of the crank to wind or unwind the band on the pulleys causes the idler pulley and arm to travel upwardly or downwardly and pivot the swivel bracket about the horizontal tilt axis. A releasable brake secures the crank against rotation to maintain a desired angle of tilt.

BACKGROUND OF INVENTION In the operation of marine propulsion units it often is necessary to tilt the marine propulsion unit for access to the propeller, for weed removal, or for travel in shallow water. A number of hydraulic and electrical devices have been provided to assist in tilting the drive shaft housing or lower unit of the marine propulsion device. Such hydraulic and electrical devices are expensive and inappropriate for some outboard motors. The present invention provides a tilting device that is particularly appropriate for intermediate size motors.

SUMMARY OF INVENTION The invention provides a device for tilting the drive shaft housing and power head of a marine propulsion unit about a horizontal tilt axis. When the drive shaft housing is in a substantially vertical position, the center of gravity of a marine propulsion unit is typically spaced aft of the horizontal tilt axis. As the drive shaft housing is tilted about the horizontal tilt axis, the center of gravity of the swingable part of the marine propulsion unit traverses an arc which extends forwardly and upwardly to a position generally above the horizontal tilt axis. As the center of gravity approaches a position vertically above the horizontal tilt axis, very little effort is required to tilt the marine propulsion unit. The present invention provides a tilting device in which the highest mechanical advantage is afforded when the drive shaft housing is substantially vertical and the greatest amount of effort is required for tilting. The mechanical advantage continuously decreases as the drive shaft housing is tilted upwardly.

The tilting device of the invention comprises a band and pulley arrangement which cooperates with an arm connecting a swivel bracket and stern bracket to afford upward tilting movement of the swivel bracket. More specifically, the stern bracket rotatably supports first and second pulleys, and one end of the band is connected to each of the pulleys. The band is also reeved around an idler pulley rotatably supported on one end of the arm. Upon rotation of the crank, which is connected to one of the pulleys on the stern bracket, the steel band winds around the pulley and draws the idler pulley and arm 3,51 1,460 Patented May 12, 1970 DRAWINGS FIG. 1 is a side elevational view of a marine propulsion unit embodying the present invention.

FIG. 2 is an enlarged fragmentary, partially broken away side elevational view of the device shown in FIG. 1.

FIG. 3 is an enlarged fragmentary, partially broken away side elevational view of the device shown in FIG. 1 with the swivel bracket in a tilted position.

FIG. 4 is an enlarged view in fragmentary section of the invention shown in FIG. 2.

FIG. 5 is an exploded perspective view of the hand crank and brake.

FIG. 6 is a vertical elevational view of a modified embodiment of the invention.

DETAILED DESCRIPTION In the drawings, FIG. 1 shows a marine propulsion unit or device which is generally designated 10 and which includes a power head 12 and a drive shaft housing 14. Mounting of the marine propulsion unit to a transom 16 of a boat hull is provided by a conventional clamp bracket or stern bracket 18. The drive shaft housing 14 is rotatably supported on a swivel bracket 22 which is connected to the stern bracket 18 by a horizontal pintle or pin 23 providing a horizontal tilt axis for the power head 12 and drive shaft housing 14.

The invention contemplates the provision of a manual tilting device in a marine propulsion unit for tilting the drive shaft housing about its horizontal tilt axis through a range of angular positions. In this regard, means are provided for connecting the stern bracket to the swivel bracket to pivot the swivel bracket about its horizontal axis. Such means are adapted for manual rotation and afford initially greater mechanical advantage when the center of gravity of the swingable part of the marine propulsion unit 10 is aft of the horizontal tilt axis and continuously decreasing mechanical advantage as the center of gravity shifts upwardly and forwardly during angular rotation of the marine propulsion unit. In the disclosed construction, the means includes a first pulley or drum 24, which is secured to a shaft 26 rotatably supported in the stern bracket 18, and a second pulley or drum 28 secured to or rotatably supported on a shaft 30 which can be fixed or rotatably supported in the stern bracket 18.

The tilting means connecting the stern bracket 18 to the swivel bracket 22 also includes an arm 32 connected to a collar 34 which is pivotally supported on a laterally extending trunnion 36 which is integral with the swivel bracket 22 and spaced from the horizontal tilt axis 23 as shown in FIG. 3. The lower end of the arm 32 has a laterally projecting shaft 38 which rotatably supports a third pulley 40.

Means are provided for connecting the arm to the stern bracket 18 for guiding movement of the arm 32 during tilting of the swivel bracket 22 about the horizontal tilt axis as hereinafter described. In the disclosed construction, such means is in the form of an elongated slot 42 in the stern bracket 18 which extends generally parallel to the transom 16 and which receives the end 44 of the shaft 38.

To protect the marine propulsion unit against damage caused by impact with an underwater obstruction, the collar has a depending peg 35 which extends into an aperture 37 in the arm 32 and which is connected to the arm 32 by a shear pin 39.

The

pulleys

24, 28 and 40 are connected by a strand or steel band 46 which is desirably flat and which has one end secured to the pulley 28 and the other end seccured to the pulley 24 with a portion reeved around the pulley 40.

Although in the disclosed construction

separate pulleys

24 and 28 are employed, in the alternative, a single drum with two sets of flanges and two different diameters could be utilized.

Means are provided for connecting the pulley 24 to the pulley 28 for rotation of the pulley 28 in a direction counter to the direction of rotation of the pulley 24 during tilting of the marine propulsion unit as hereinafter described. In the construction disclosed in FIGS. 2 and 3, the means includes teeth 48 on adjacent flanges 49 of each of the

pulleys

24, 28.

A crank 50 is secured to shaft 26 for rotating pulley 24 to wind or release the band 46 for varying the angle of tilt of the drive shaft housing about its horizontal tilt axis 20. As shown in FIG. 5, the crank 50- has an aperture 51 with angularly related surfaces which interfit with complementary surfaces 53 on the end of the shaft 26. A bolt 55 threads into the axial aperture 57 in the shaft 26 to secure the crank 50 to the shaft 26.

The invention also provides means for securing the swivel bracket against rotation to maintain the drive shaft housing 14 at a desired angle of tilt. As shown in FIGS. 4 and 5, the means comprises cam surfaces or segments 52 circumferentially arranged around a hollow boss or extension 54 which projects from the stern bracket 18 and which rotatably supports the shaft 26. The means also includes a collar 56 having cam surfaces or segments 58 and a radially extending lever 60 adapted to be manipulated by the operator. A friction washer or brake band 62 is located on the boss 54 between the face 63 of the crank or handle 50 and the collar 56. To secure the shaft 26 against rotation and fix the angle of tilt, the lever 60 is moved to rotate the collar until the cam surfaces 58 and 52 coopearte to move the collar 56 axially and urge the washer 62 against the face 63 of the hand crank 50.

To operate the manual tilt of the invention, and to tilt the swivel bracket from the substantially vertical position shown in FIGS. 1 and 2 to the angular position shown in FIG. 3, the crank handle 50 is turned to rotate the pulley 24 and wind thereon the band 46, thereby increasing the diameter of the pulley 24, and decreasing the diameter of the pulley 28 and thereby also causing upward travel of the pulley 40 and the shaft 38 in the slot 42. The upward travel of the pulley 40 causes upward movement of the arm 32 and thus pivots the swivel bracket 22 about the horizontal tilt axis 20.

When the swivel bracket is in the substantially vertical position shown in FIG. 2, the diameters of the

pulleys

24 and 28 are desirably equal to provide maximum mechanical advantage. In this position, the center of gravity of the swingable part of the marine propulsion unit i.e., the drive shaft housing 14, is aft of the stern bracket, and the lifting force required for pivotal movement is the maximum. Upon rotation of the crank 50, the band 46 will wind on the pulley 24 and increase the diameter of the pulley 24, and unwind on the pulley 28, decreasing the diameter of the pulley 28. The mechanical advantage thus continually decreases as the swivel bracket is tilted upwardly about the horizontal tilt axis 20, carrying the drive shaft housing 14 upwardly from its normal operating position. As the center of gravity of the swingable part of the marine propulsion unit traverses an elongated arcurate path 65 upwardly and toward the horizontal tilt axis 20, the lifting force required to afford angular rotation of the swivel bracket decreases, and less mechanical advantage is required to produce the same lifting force. As the diameter of the pulley 24 increases, each turn of the crank 50 will cause greater angular movement of the drive shaft housing 14. When the marine propulsion unit has attained the desired angle of tilt, the lever 60 can be moved to secure the shaft 26 against rotation.

In the modified embodiment of the invention illustrated in FIG. 6, means are provided to yieldably iestrain upward pivotal movement of the drive housing 14 and the sewivel bracket 22.

In the disclosed construction, the means comprises an arm 66 which has co-axial apertures 74 in inturned flanges 75, 76 at each end of the arm 66. The arm 66 has an outturned shaft portion 77 which extends into the elongated slot 42 and rotatably carries the pulley 40. The arm 66 is connected to the trunnion 36 by a collar 78 rotatably supported on the trunnion 36. The collar has a stem 80 secured thereto, which extends through apertures 74. A spring 82 is arranged over the stem 80 and located against the flange 76. A cross pin 84 secures the other end of the spring 82.

During upward movement of the swivel bracket 22 upon tilting the drive shaft housing, as the shaft 77 engages the upper end of the slot 42, further angular movement of the swivel bracket beyond the limit imposed by the slot 42 will cause the arm 66 to telescope over the stem 80, i.e. move downwardly in FIG. 6 and pull away from engagement with the collar 78, against the biasing of spring 82, which yieldably restrains further travel of the swivel bracket 22 to minimize any possibility of damage to the stern bracket 18.

Various of the features of the invention are set forth in the following claims.

What is claimed is:

1. A marine propulsion unit comprising a stern bracket, a swivel bracket pivotally mounted to said stern bracket for movement about a horizontal axis, a manually operable handle rotatably mounted on said stern bracket about an axis parallel to and spaced from said horizontal axis and means connecting said handle to said swivel bracket for pivoting said swivel bracket about said horizontal tilt axis in response to rotary handle movement relative to said stern bracket.

2. A marine propulsion unit comprising a stern bracket, a swivel bracket pivotally mounted to said stern bracket for movement about a horizontal axis, a drive shaft housing connected to said swivel bracket, means connecting said stern bracket to said swivel bracket and adapted for manual rotation for pivoting said swivel bracket about said horizontal tilting axis, said means connecting said stern bracket to said swivel bracket including means for initially providing greater mechanical advantage when said drive shaft housing is in its normal operating position and continually decreasing mechanical advantage as said drive shaft housing is pivoted upwardly from the normal operating position.

3. The combination, in a marine propulsion unit, of a stern bracket, a swivel bracket pivotally mounted to said stern bracket for movement about a horizontal axis, a first pulley rotatably supported by said stern bracket, a second pulley rotatatably supported by said stern bracket, a crank connected to said first pulley, and arm having one end pivotally connected to said swivel bracket at a point spaced from said horizontal tilt axis, a third pulley rotatably supported on the other end of said arm, and a band connected to said first pulley and said second pulley and reeved around said third pulley to afford movement of said swivel bracket about said horizontal axis upon rotation of said first pulley.

4. The device of claim 3 including means for connecting the arm to the stern bracket for guiding movement of said arm during tilting of said swivel bracket.

5. The improvement of claim 4 wherein said means for guiding movement of said arm comprises an elongated slot in said stern bracket, and a shaft projecting from the end of said arm into said slot.

6. The improvement of claim 3 including means connecting said first pulley to said second pulley to counterrotate said second pulley upon rotation of said first pulley.

7. The improvement of claim 6 wherein said means connecting said first pulley to said second pulley to counterrotate said second pulley comprises flanges on each of said pulleys, each of said flanges having teeth in meshing engagement.

8. The device of claim 1 including a releasable brake means for securing said swivel bracket against rotation to maintain said swivel bracket at a desired angle relative to said stern bracket.

9. The improvement of claim 3 including means for yieldably restraining upward tilting movement of said swivel bracket.

10. The improvement of claim 9 wherein said means for yieldably restraining upward tilting movement of said swivel bracket comprises an arm having upper and lower inturned flanges, said flanges having co-axial apertures, a stem extending through said apertures, said stem having an upper end rotatably mounted on said swivel bracket, a cross pin extending through said stem, and a spring located between said cross pin and said upper flange of said arm.

11. A marine propulsion device comprising a stern bracket, a drive shaft housing pivotally mounted to said stern bracket for vertical swinging movement about a horizontal tilt axis, a manually operable handle rotatably mounted on said stern bracket about an axis parallel to and spaced from said horizontal axis, and means connecting said handle to said drive shaft housing for tilting of said drive shaft housing about said horizontal tilt axis in response to rotary handle movement relative t said stern bracket.

12. The combination, in a marine propulsion unit, of a stern bracket, a swivel bracket pivotally mounted to said stern bracket for movement about a horizontal axis, an arm having one end pivotally mounted on said swivel bracket at a point spaced from said horizontal tilt axis, and means on said stern bracket and connected to the other end of said arm for elevating said other end of said arm relative to said stern bracket to rock said swivel bracket upwardly about said horizontal axis.

13. The combination, in an outboard motor, of a stern bracket, a swivel bracket pivotally mounted to said stern bracket for movement about a horizontal axis, a first pulley rotatably supported by said stern bracket, a second pulley on said swivel bracket, a crank connected to said first pulley, and a band connected to said first pulley and reeved around said second pulley to afford movement of said swivel bracket about said horizontal axis upon rotation of said first pulley.

14. The combination in a marine propulsion unit of a stern bracket, a swivel bracket pivotally mounted to said steering bracket for movement about a horizontal axis, a rotatable member on said stern bracket, means connecting said rotatable member to said swivel bracket for effecting movement of said swivel bracket about said horizontal axis upon rotation of said rotatable member, and a brake band mounted for movement into engagement with said rotatable member to prevent rotation thereof and thereby prevent swivel bracket movement about said horizontal axis.

15. The device of claim 8 wherein said releaseable brake means comprises a brake band engageable with said handle to prevent rotation thereof, and means for selectively engaging said band with said handle.

References Cited UNITED STATES PATENTS 2,940,715 6/ 1960 Schultz et al.

600,854 3/1898 Bolens 248-406 825,822 7/ 1906 Gilson 248406 2,454,972 11/ 1948 Martin 2484 2,782,744 2/ 1957 Staley 2484 X 2,961,207 11/1960 Irgens 2484 1,845,712 2/1932 Jacques -41 2,454,972 11/ 1948 Martin 248291 XR 3,008,444 11/1961 Bovy 115-41 3,016,869 1/1962 Anderson et al. l15--17 ROY D. FRAZIER, Primary Examiner J. F. FOSS, Assistant Examiner US. Cl. X.R.