This invention relates to steering assemblies for simultaneously steering two or more marine propulsion units, and in particular, to a connecting member for coupling the propulsion units together, allowing for simultaneous steering.
Hydraulic steering systems have been developed for marine propulsion units. Such steering systems conventionally include a steering wheel with an associated hydraulic pump and hydraulic lines connecting the pump to a steering assembly. The steering assembly is mounted on a propulsion unit. In some earlier systems, the steering assembly includes a pivot plate or pivot member which is pivotally connected to the tiller of an outboard motor or other propulsion unit. A pair of support arms or support brackets extend outwardly from the tilt tube of the motor. The piston rod of a hydraulic actuator is mounted on the support arms. The actuator has connecting members extending outwardly from the cylinder thereof which are pivotally connected to the pivot member for pivoting about an axis parallel to the piston rod.
When there are two or more propulsion units, a tie-bar typically connects the steering assembly to the second propulsion unit. Conventionally, the tie-bar is connected to the tillers or to plates attached to the tillers. More recently, as disclosed in U.S. Pat. No. 6,406,340 to Fetchko et al., the tie-bar has been connected to a member attached to the pivot plate, allowing for rotation of the steering assembly about a steering axis and arcuate movement of the steering assembly about a tilt axis that is generally perpendicular to the steering axis.
According to one aspect of the invention, there is provided a hydraulic steering assembly for applying a force to two or more marine propulsion units. Each propulsion unit has a steering axis and a tilt axis, the tilt axis being generally perpendicular to the steering axis thereof. Each propulsion unit is rotatable about the steering axis thereof and is supported for arcuate movement about the tilt axis thereof. The steering assembly comprises a hydraulic steering actuator, including a cylinder and an elongated piston rod. The cylinder has a first end and a second end. The elongated piston rod is reciprocatingly mounted within the cylinder and extends through the cylinder for movement along a piston rod axis.
A pair of support arms are pivotable about the tilt axis of a first said propulsion unit. The support arms are connected to the piston rod, allowing arcuate movement of the piston rod about the tilt axis while maintaining the piston rod axis parallel to the tilt axis. A pivot member is pivotally mounted on the first said propulsion unit for pivoting about a first link axis, which is generally parallel to the steering axis. The actuator is pivotally connected to the pivot member for pivoting about a second link axis, which is generally parallel to the piston rod axis. A connecting member is connected to the actuator. An elongated member is pivotally connected to the connecting member and the elongated member is connected to a second said propulsion unit.
The elongated member may be pivotally connected to the connecting member by a ball joint. The connecting member may be connected to the actuator, however, the connecting member may also be formed in one piece with the actuator. The connecting member may also be connected to the pivot member, the pivot member preferably being a pivot plate. The assembly may have the connecting member connected to the first end of the cylinder and another connecting member connected to the second end of the cylinder, the connecting members may be pivotally connected to the pivot plate for pivoting about the second link axis.
According to another aspect of the invention, there is provided a connecting member for a hydraulic steering actuator. The actuator includes a cylinder and an elongated piston rod reciprocatingly mounted within the cylinder. The piston rod extends through the cylinder for movement along a piston rod axis. The actuator steers two or more marine propulsion units. Each said propulsion unit is rotatable about a steering axis and about a tilt axis which is generally perpendicular to the steering axis thereof.
The connecting member comprises a means for connecting the connecting member to the actuator and a means for pivotally connecting an elongated member to the connecting member. The elongated member may also be connected to a second marine propulsion unit, allowing for simultaneous steering of the first said propulsion unit and the second said propulsion unit.
The means for connecting the connecting member to the actuator may include a first cylindrical projection. The connecting member may be connected to the actuator by inserting the first cylindrical projection into the cylinder. The means for pivotally connecting the connecting member to the elongated member may include a clevis. The elongated member may be connected to the connecting member at the clevis by a ball joint.
Preferably, the connecting member includes a first potion and second portion. The first portion may have a first side and a second side, the first side being opposite to the second side. The second portion may also have a first side and a second side, the first side being opposite to the second side. An aperture may extend from the first side of the first portion through to the second side of the first portion. A clevis may be on the first side of the second portion. A first cylindrical projection may be on the second side of the first portion. The first cylindrical projection may be circumambient to the aperture. A second cylindrical projection may be on the first side of the second portion.
According to a further aspect of the invention, there is provided a hydraulic steering assembly for applying a force to two or more marine propulsion units. Each propulsion unit has a steering axis and a tilt axis, the tilt axis being generally perpendicular to the steering axis thereof. Each propulsion unit is rotatable about the steering axis thereof and is supported for arcuate movement about the tilt axis thereof. The method comprises connecting an elongated member to a hydraulic steering actuator of a first said propulsion unit and connecting the elongated member to a second said propulsion unit.
The elongated member may be pivotally connected to the actuator. A steering force for the second said propulsion unit may be transferred from the actuator along the elongated member to the second said propulsion unit. The elongated member may be pivotally connected to the second said propulsion unit.
In a typical prior art unit the elongated member is bolted to the pivot plate. This results in large offset forces. By attaching the elongated member directly to the actuator the load point is more aligned with the rotational axis and offset forces which may stress the steering assembly are reduced. This results in a steering assembly that is safer and more robust.
The invention offers a further advantage over to the prior art by reducing the number of bolted connections, consequently reducing cost and assembly time.
In the drawings:
Referring to the drawings, and first to
There is a pivot member, in this case a pivot plate 30. The pivot plate 30 is pivotally mounted on a propulsion unit 31, shown in fragment in
End portion 35 is shown in better detail in
The end portions 35 and 36 each also have an aperture 50, which is co-axially aligned with the piston rod axis. The piston rod 20 extends slidably through the aperture 50. There is a first cylindrical projection 52 that is circumambient to the aperture 50. The first cylindrical projection 52 is received within the cylinder 16, connecting the end portion to the cylinder 16. Bolts (not shown) extend through apertures 60 and 62 and corresponding threaded apertures in the cylinder 16.
The end portions 35 and 36 each further have a second cylindrical projection 54 which is co-axially aligned with the second link axis 96 when the end portions are installed. The second cylindrical projection of each of the end portions is rotatably received within a complementary recess 97 of the pivot plate 30, as shown in
End portion 35, as shown best in
In this embodiment the elongated member 65 is connected to end portion 35 at one end of the actuator 15. However, it could be pivotally connected to the actuator 15 by a connecting member or some other pivotal connection elsewhere on the cylinder. For example the connection could be between the ends of the cylinder.
It will be understood by someone skilled in the art that many of the details provided above are given by way of example only and can be altered or deleted without departing from the scope of the invention as set out in the following claims.
Number | Name | Date | Kind |
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4573930 | Queen | Mar 1986 | A |
4778418 | Mondek | Oct 1988 | A |
4836812 | Griffiths | Jun 1989 | A |
5092801 | McBeth et al. | Mar 1992 | A |
5643022 | Wagner | Jul 1997 | A |
5997370 | Fetchko et al. | Dec 1999 | A |
6406340 | Fetchko et al. | Jun 2002 | B1 |
6913497 | Ahlswede et al. | Jul 2005 | B1 |
Number | Date | Country | |
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20060154535 A1 | Jul 2006 | US |