Spindle with overmolded bushing
A propeller assembly is provided for mounting on a propeller shaft of a watercraft. The propeller assembly includes a housing structure having a plurality of blades projecting radially therefrom. A bushing assembly translates rotational movement of the propeller shaft to the housing structure. The bushing assembly includes a spindle having an inner surface that meshes with the outer surface of a propeller shaft and a resilient bushing molded over the spindle. A plurality of spaced, longitudinally extending keys extend along the outer surface of the spindle. In the event that the propeller blades become fixed during operation of the watercraft, the keys fragment from the outer surface of spindle so as to disengage the spindle from the housing structure. In such manner, damage to the engine and to the drive system of the marine vehicle may be avoided.
1. A propeller assembly for mounting on a rotatable propeller shaft of a watercraft, comprising:
a housing structure extending along a longitudinal axis and having an inner surface defining passageway therethrough, the inner surface including a first portion being a first radial distance from the longitudinal axis and a second portion being a second radial distance from the longitudinal axis;
a spindle receivable in the passageway of the housing, the spindle having an inner surface defining a passageway for receiving the propeller shaft therethrough and an outer surface; and
a longitudinally extending key extending along the outer surface of the spindle, the key including a radially outer surface being a third radial distance from the longitudinal axis;
wherein the third radial distance is greater than the first radial distance and less than the second radial distance.
2. The propeller assembly of claim 1 further comprising a bushing molded over the outer surface of the spindle, the bushing including an outer surface engageable with an inner surface of the housing structure.
3. The propeller assembly of claim 2 wherein the bushing is formed from a resilient material.
4. The propeller assembly of claim 3 wherein the bushing has a generally square-shaped cross section and rounded corners.
5. The propeller assembly of claim 1 wherein the inner surface of the spindle includes a plurality of longitudinally extending splines.
6. The propeller assembly of claim 1 wherein the inner surface of the housing structure has a generally square-shaped cross section.
7. The propeller assembly of claim 1 wherein inner surface of the housing structure is defined by:
first and second spaced sidewalls, the first and second sidewalls being generally parallel to each other; and
third and fourth spaced sidewalls, the third and fourth sidewalls being generally parallel to each other and being generally perpendicular to the first and second spaced sidewalls.
8. The propeller assembly of claim 7 wherein the inner surface of the housing structure is further defined by:
a first rounded corner interconnecting the first and third sidewalls;
a second rounded corner interconnecting the third and second sidewalls;
a third rounded corner interconnecting the second and fourth sidewalls; and
a fourth rounded corner interconnecting the fourth and first sidewalls.
9. The propeller assembly of claim 1 wherein the key fragments from the outer surface of the spindle in response to a predetermined force thereon.
10. The propeller assembly of claim 1 wherein the key fragments from the outer surface of the spindle in response to a predetermined force thereon.
11. A propeller assembly for mounting on a rotatable propeller shaft of a watercraft, comprising:
a housing structure extending along a longitudinal axis, the housing structure including an outer surface and an inner surface defining a cavity having a polygonal-shaped cross-section defined by at least one corner and at least one sidewall, the inner surface including a first portion being a first radial distance from the longitudinal axis and a second portion being a second radial distance from the longitudinal axis; and
a bushing assembly receivable in the cavity of the housing structure, the bushing assembly including:
a spindle having an inner surface defining a passageway for receiving the propeller shaft therethrough and an outer surface having a longitudinally extending key extending therealong, the key extending radially from the outer surface of the spindle toward a first corner of the at least one corner of the inner surface of the housing structure wherein the key comprises a radially outer surface being a third radial distance from the longitudinal axis;
wherein the third radial distance is greater than the first radial distance and less than the second radial distance; and
a bushing molded over the spindle, the bushing having an outer surface engageable with the inner surface of the housing structure.
12. The propeller assembly of claim 11 wherein the bushing is formed from a resilient material.
13. The propeller assembly of claim 11 wherein the inner surface of the spindle includes a plurality of longitudinally extending splines.
14. The propeller assembly of claim 11 wherein the outer surface of the housing structure has a plurality of circumferentially spaced blades projecting therefrom.
15. The propeller assembly of claim 11 wherein the inner surface of the housing structure has a generally square-shaped cross section.
16. The propeller assembly of claim 15 wherein the at least one sidewall of the inner surface of the housing structure includes:
first and second spaced sidewalls, the first and second sidewalls being generally parallel to each other; and
third and fourth spaced sidewalls, the third and fourth sidewalls being generally parallel to each other and being generally perpendicular to the first and second spaced sidewalls.
17. The propeller assembly of claim 16 wherein the at least one corner of the inner surface of the housing structure includes:
a second corner interconnecting the third and second sidewalls;
a third corner interconnecting the second and fourth sidewalls; and
a fourth corner interconnecting the fourth and first sidewalls.
18. A propeller assembly for mounting on a rotatable propeller shaft of a watercraft, comprising:
a housing structure extending along a longitudinal axis, the housing structure including an outer surface and an inner surface defining a cavity, the inner surface including a first portion being a first radial distance from the longitudinal axis and a second portion being a second radial distance from the longitudinal axis and defined by:
first and second spaced sidewalls, the first and second sidewalls being generally parallel to each other;
third and fourth spaced sidewalls, the third and fourth sidewalls being generally parallel to each other and being generally perpendicular to the first and second spaced sidewalls;
a first rounded corner interconnecting the first and third sidewalls;
a second rounded corner interconnecting the third and second sidewalls;
a third rounded corner interconnecting the second and fourth sidewalls; and
a fourth rounded corner interconnecting the fourth and first sidewalls;
a bushing assembly including:
a spindle having an inner surface defining a passageway for receiving the propeller shaft therethrough and an outer surface having a plurality of circumferentially spaced, longitudinally extending keys extending therealong, each key of the spindle being directed toward a corresponding corner of the inner surface of the housing structure wherein said keys each comprise a radially outer surface being a third radial distance from the longitudinal axis:
wherein the third radial distance is greater than the first radial distance and less than the second radial distance; and
a bushing molded over the spindle, the bushing having an outer surface engageable with the inner surface of the housing structure.
19. The propeller assembly of claim 18 wherein the bushing is formed from a resilient material.
20. The propeller assembly of claim 18 wherein the inner surface of the spindle includes a plurality of longitudinally extending splines.