Shift mechanism for outboard motor

Details Shift mechanism for outboard motor Shift mechanism for outboard motor

2003-05-29

2004-12-28

Swinehart, Ed (Department: 3617)

Marine propulsion

Screw propeller

Having transmission

C440S086000

Reexamination Certificate

active

06835109

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a shift mechanism for an outboard motor.
2. Description of the Related Art
In outboard motor shift mechanisms, shift is usually changed by moving a shift rod having a cam at its distal end in the longitudinal direction to slide a shift slider such that a clutch is switched from its neutral position to a forward position where it engages with a forward gear or a reverse position where it engages with a reverse gear.
Alternatively, as shown in
FIG. 13
, a shift rod
200
is provided with a rod pin
202
at a position eccentric from the rod center
200
c
, in such a way that a shift slider
204
is slid to effect shift by a distance due to a displacement of the rod pin
202
caused by a rotation of the shift rod
200
in a direction indicated by an arrow. The distance of travel of the rod pin
2002
corresponds to a circular arc whose radius is the amount of eccentricity of the rod pin
202
. The angle of rotation of the shift rod
200
(i.e., the displacement angle of the rod pin
202
) when the clutch engages with the forward gear or reverse gear (more specifically, when the clutch is in-gear), is about plus/minus 30 degrees, when the neutral position of the rod pin
202
(shown by a phantom line) is defined as zero.
In the outboard motor shift mechanisms including that illustrated in
FIG. 13
, when the shift rod is operated manually, since the operator tends to have an unpleasant operation “feel” owing to, for instance, heavy load, it has hitherto, been proposed installing an actuator at the hull and connecting it with the shift rod in the outboard motor through a cable or a link mechanism to power-assist the driving of the shift rod, i.e. the shift. The add-on system using such an actuator has disadvantages that its structure is complicated, that it adds to the number and weight of the components, and it needs a space for the actuator at the hull.
Moreover, since the angular range of rotation of the shift rod when the clutch is engaged (in-gear), approximately plus/minus 30 degrees as mentioned above, this causes the shift slider to produces a reaction force to return to the neutral position, that acts on the shift rod as a torque to rotate it. In order to ensure the “in-gear” state, it becomes necessary to add a retainer that can retain the shift rod at that angle against the force. This makes the structure more complicated and increases the number and weight of the components.
SUMMARY OF THE INVENTION
An object of the present invention is therefore to overcome the foregoing issues by providing a shift mechanism for an outboard motor that improves operation feel, is simply configured to avoid an increase in the number of components and weight, while avoiding a problem regarding space utilization.
In order to achieve the foregoing object, this invention provides a shift mechanism for an outboard motor mounted on a stern of a boat and having an internal combustion engine at its upper portion and a propeller at its lower portion that is powered by the engine to propel the boat, comprising: a clutch installed in the outboard motor to be engaged from a neutral position with at least one of a forward gear that causes the boat to be propelled in a forward direction and a reverse gear that causes the boat to be propelled in a direction reverse to the forward direction; a shift rod movably installed in the outboard motor; an actuator installed in the outboard motor to move the shift rod; and a shift slider, installed in the outboard and connected to the shift rod to slide to at least one of a position at which the clutch is engaged with the forward gear and a position at which the clutch is engaged with the reverse gear.


REFERENCES:
patent: 3919964 (1975-11-01), Hagen
patent: 4865570 (1989-09-01), Higby et al.
patent: 5230643 (1993-07-01), Kanno
patent: 6217400 (2001-04-01), Natsume
patent: 6346017 (2002-02-01), Silorey et al.

Affiliated with

Also associated with

Rating

Shift mechanism for outboard motor does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Shift mechanism for outboard motor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Shift mechanism for outboard motor will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3327173