U.S. patent application number 11/539526 was filed with the patent office on 2007-06-07 for torsional control boat throttle system.
Invention is credited to Charles S. BLAIR, Stephen Lee Olson.
Application Number | 20070128956 11/539526 |
Document ID | / |
Family ID | 46326265 |
Filed Date | 2007-06-07 |
United States Patent
Application |
20070128956 |
Kind Code |
A1 |
BLAIR; Charles S. ; et
al. |
June 7, 2007 |
TORSIONAL CONTROL BOAT THROTTLE SYSTEM
Abstract
A torsional throttle control system is provided that may include
any of a number of features. One feature of the throttle control
system is twist-style grip that has an axis with an angle
adjustable to a housing. Another feature comprises trim and/or
outboard motor control(s) atop the grip. Yet another feature
comprises the internal mechanism adapted to effect throttle
control. Methods associated with use of the throttle control
hardware and systems including a boat are also covered.
Inventors: |
BLAIR; Charles S.; (Redwood
City, CA) ; Olson; Stephen Lee; (Los Altos,
CA) |
Correspondence
Address: |
BOZICEVIC, FIELD & FRANCIS LLP
1900 UNIVERSITY AVENUE
SUITE 200
EAST PALO ALTO
CA
94303
US
|
Family ID: |
46326265 |
Appl. No.: |
11/539526 |
Filed: |
October 6, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11063700 |
Feb 22, 2005 |
7172478 |
|
|
11539526 |
Oct 6, 2006 |
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Current U.S.
Class: |
440/87 |
Current CPC
Class: |
B63H 21/213
20130101 |
Class at
Publication: |
440/087 |
International
Class: |
B63H 21/21 20060101
B63H021/21 |
Claims
1. A throttle control assembly comprising: a twist handle having a
longitudinal axis of rotation; a flexible shaft having a first end
coupled to the twist handle, wherein rotation of the handle about
its axis rotates at least a portion of the flexible shaft to
provide an output for throttle control, and wherein the axis of the
twist handle is adjustable relative to a fixed housing.
2. The assembly of claim 1, wherein the twist handle axis is
adjustable between about 15 and about 90 degrees.
3. The assembly of claim 1, wherein the flexible shaft has a second
end coupled to a rotatable arm, and wherein the rotatable arm has a
distal end coupled to a push-pull cable to provide the output for
throttle control.
4. The assembly of claim 3, wherein the rotatable arm comprises a
sector, wherein a ball detent interfaces with detent positions
spaced around the sector.
5. The assembly of claim 1, wherein a detent means is provided for
the handle axis adjustment.
6. The assembly of claim 1, further comprising at least one of trim
and motor up/down buttons atop the handle.
7. The assembly of claim 1 set in a housing, the housing further
comprising a gear shifter.
8. The assembly of claim 1, further comprising a cable, the cable
connected to a rack gear meshing with a pinion gear, the pinion
gear positioned to actuate fuel supply to an engine or motor.
9. A throttle control, the controller having a rotatable handle to
control engine or motor throttle, wherein the improvement
comprises: the grip having an axis, wherein the axis is adjustable
to a base at an angle without effecting steering.
10. The throttle assembly of claim 9, wherein a detent means is
provided for the adjustment.
11. The throttle assembly of claim 9, wherein a position of the
grip can be locked at a desired point of adjustment.
12. A throttle control, the controller having a rotatable handle to
control engine or motor throttle, wherein the improvement
comprises: at least one of a trim and an outboard up/down buttons
atop the handle.
13. A boat comprising: a hull, at least one motor, and a throttle
control as described in claim 1 mounted to or integrated with the
boat.
14. A boat comprising: a hull, at least one motor, and a throttle
control as described in claim 9 mounted to or integrated with the
boat.
15. A boat comprising: a hull, at least one motor, and a throttle
control as described in claim 12 mounted to or integrated with the
boat.
16. A method of operating a boat by a user having first and second
hands, the method comprising: grasping a steering wheel with the
first hand, grasping a throttle control having a fixed location
with the second hand, and substantially maintaining a body position
while effecting throttle control by supporting the body from
forward and aft movement with the wheel and throttle control.
17. The method of claim 16, further comprising adjusting at least
one of trim and motor up/down without substantially altering the
second hand position.
18. The method of claim 16, wherein the fixed location of the
throttle control is adjustable by a user before it is fixed.
19. A method of operating a boat by a user having first and second
hands, the method comprising: grasping a throttle control with the
first hand, and adjusting at least one of trim and motor up/down
with the first hand while grasping the throttle control.
20. The method of claim 19, further comprising grasping a steering
wheel with the second hand while grasping the throttle control with
the first hand.
Description
CROSS REFERENCES
[0001] This application is a continuation-in-part application of
Ser. No. 11/063,700, filed Feb. 22, 2005, which is incorporated
herein by reference in its entirety noting that the current
application controls to the extent there is any contradiction with
an earlier application and to which application we claim priority
under 35 USC .sctn. 120.
FIELD OF THE INVENTION
[0002] The present invention relates to throttle controls for
vehicles, particular watercraft. The invention also relates to the
manner of converting user control input to output, as well as
translation of that output to action at a remote location.
BACKGROUND OF THE INVENTION
[0003] A number of known throttle controls for watercraft employ a
twist-grip type of interface connected to an electronic control
unit. These are found in connection with electric trolling motors.
Twist of the grip controls motor speed. Typically, the grip also
serves as a tiller, in which its point dictates the direction of
the motor connected thereto by a tube or shaft.
[0004] More sophisticated throttle control systems are shown in
U.S. Pat. Nos. 6,053,781 and 6,776,671. In each patent, the
tiller/throttle grip assembly is removed from the propeller tube
and setup at a remote location. In the '781 patent, the direction
the propeller points is controlled by a separate lever arm with
push-pull ropes/cables wrapped around a component connected to the
motor tube. The motor control unit with its grip is located
amidship oriented vertically. In the '671 patent, the motor control
head and throttle control grip are mounted alongside the pilot's
seat. The control head is mounted on a rod so that it can rotate
around the axis that is in-line with the boat to actuate a linkage
assembly attached to propeller tube to effect steering.
[0005] While these systems offer benefits, their use is
contemplated only in connection with electric trolling motors.
Furthermore, neither system offers angular adjustability of the
throttle grip independent of steering control. In the '781 patent,
no angular adjustability is available with the fixed unit. In the
'671 patent one cannot simply adjust the angle of the grip to a
desirable position while operating the boat, since to do so would
set an unintended course. Moreover, trolling motors are suited only
for driving a small boat at a speed of a few knots/mph, and in calm
water. The inventor hereof has appreciated the benefits of a
throttle grip type system for use in a vastly different context.
Particularly, the present invention finds use in high power
speedboats as a means of control for the primary source of
propulsion. Benefits and advantages of the current system are
elaborated upon below.
SUMMARY OF THE INVENTION
[0006] The present invention is a throttle assembly using a twist
grip type user interface. The throttle control assembly is provided
for use in connection with powerboats, especially those suited for
use in rough (open ocean) water and/or at high speed (i.e., greater
than, for example, 30 knots/35 mph) in racing, etc.
[0007] The throttle assembly of the present invention typically
controls at least one large internal combustion engine. The present
invention offers particular advantages in connection with racing
boats in which the user sits in a tight cockpit and the boat is
planning across the water at very high speeds (upwards of 75 mph in
a typical race). At such speeds, the wakes of other boats or wave
action produces an extremely rough or "bumpy" ride. A grip-style
throttle according to the present invention, then, provides a user
something stable to hold onto in order to help maintain body
position, and avoid injury as is common from banging fingers,
elbows etc. while being tossed around in the cockpit of a scarab or
another type of racing boat.
[0008] In one aspect of the invention, the grip drives a mechanical
gear system that operates a control cable. The cable may be coupled
directly to a lever arm attached to the throttle shaft of a marine
engine or motor. Alternatively, the cable can actuate a rack in a
rack-and-pinion arrangement in which the pinion is mounted on the
throttle shaft itself. In this manner, truly linear throttle
control can be achieved since change in lever arm angle is
avoided.
[0009] One aspect of the invention concerns the engine-side
rack-and-pinion itself, alone or in combination with the throttle
grip assembly. Another aspect of the invention concerns a throttle
grip that is adjustable by a user (in use or adjusted and then set
to a position) relative to a fixed housing. The adjustment serves
to optimize user comfort and/or available support.
[0010] Yet another aspect of the invention provides control
features atop the throttle grip. These may be buttons, switches,
etc. which are preferably positioned within reach of the user's
thumb so that they may be actuated without changing grip on the
throttle. These controls advantageously actuate right and/or left
trim tabs and/or outboard motor or outdrive up/down adjustment. The
throttle grip is advantageously shaped both to provide space for
mounting the control features and for facilitating reach to actuate
the controls. As such, the grip may have an ergonomic shape, with a
surface for mounting the controls canted towards the thumb position
for a user.
[0011] The invention also comprises methods, in which the methods
may involve use of the subject devices. The methods may be
practiced with other devices than those described herein. Yet, the
acts associated with the use of such other devices will be
typically be in accordance with those associated with the devices
described herein.
[0012] In any case, one method according to the present invention
involves operating a boat in which the user grasping a steering
wheel with one hand and the throttle control with the second hand,
and substantially maintains a body position while effecting
throttle control by supporting the body from forward and aft
movement with the wheel and throttle control. The user is able to
do so since throttle control merely requires twisting the handgrip.
In comparison, where one or more levers are the means of throttle
control, the back and forth movement of the levers alter body
position. Further, it is not possible to support the body against
forward and aft movement by grasping a throttle lever free to move
in the same plane. The method may further comprise adjusting at
least one of trim and motor up/down without releasing the throttle
grip.
[0013] Another method according to the invention includes grasping
a throttle control with one hand and adjusting at least one of trim
and motor up/down with that hand while grasping the throttle
control. Typically, this will be accomplished using the thumb. The
method advantageously further comprises grasping a steering wheel
with the second hand while grasping the throttle control with the
first hand. Most advantageously, the throttle is a grip-type twist
throttle so that the user can maintain a stable position while
operating the boat.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Each of the figures diagrammatically illustrates aspects of
the invention. Of these:
[0015] FIG. 1A is an oblique view of the type of boat with which
the invention is advantageously used; FIG. 1B is a partial view of
the stem of the boat; FIG. 1C is an aerial view of the helm of the
boat, including a throttle controller according to aspects of one
embodiment of the present invention;
[0016] FIG. 2A shows an oblique overview of the throttle controller
assembly; FIG. 2B details the interior of the throttle controller
assembly in oblique cut-away view;
[0017] FIG. 3 illustrates an engine-side throttle control
system;
[0018] FIG. 4A shows an oblique overview of another embodiment of a
throttle controller assembly according to aspects of the present
invention; FIG. 4B details the interior of the throttle controller
assembly in a front end cut-away view; FIG. 4C details the interior
of the throttle controller assembly in a side cut away view with
rotating arm 176 in an aft position; FIG. 4D details the interior
of the throttle controller assembly in a side cut away view with
rotating arm 176 in a forward position; and
[0019] FIG. 5 shows an oblique overview of another embodiment of a
throttle grip according to aspects of the present invention.
[0020] Variation of the invention from that shown in the figures is
contemplated.
DETAILED DESCRIPTION
[0021] The following description focuses on one variation of the
present invention. The variation of the invention is to be taken as
a non-limiting example. It is to be understood that the invention
is not limited to particular variation(s) set forth and may, of
course, vary. Changes may be made to the invention described and
equivalents may be substituted (both presently know and
future-developed) without departing from the true spirit and scope
of the invention. In addition, modifications may be made to adapt a
particular situation, material, composition of matter, process,
process act(s) or step(s) to the objective(s), spirit or scope of
the present invention.
[0022] FIG. 1A shows a "scarab" type speedboat 2 banking or turning
at high speed across the water 4. As shown, it produces a
substantial wake 6. An operator or pilot 8 sits in a seat 10
located at the starboard side 12 of the watercraft. A co-pilot (not
shown) would typically sit to the port side 14 of the vessel. The
present invention is advantageously used in connection with such a
watercraft. However, the invention may be put to good use with
other types of boats.
[0023] FIG. 1B provides a partial view of the stem 16 of boat 2
opposite bow 18. Trim tabs 20, exhaust pipes 22, and outboard
engine 24 components are shown. FIG. 1C shows the cockpit of boat
26 including chairs 10, wheel 28, gauges 30, switch bank 32,
ignition 34 and a control system 40 according to the present
invention.
[0024] In use, the pilot or captain of the vessel will steer with
the left hand and control engine direction and speed with the right
hand using controller 40. Since the controller grip 42 is fixed in
a forward-aft direction (in contrast to) the gear selector 44, the
throttle control grip offers a stable interface for support.
[0025] Further details of the subject throttle controller are
better appreciated in reference to FIGS. 2A and 2B. The former
figure shows a fully assembled view of control package 40; the
later figure a cutaway view of the throttle control portion of the
device.
[0026] The gear selector arm 44 allows the user to select the
direction in which to propel the boat by switching the transmission
(not shown) between forward and reverse. Selector 44 and its
associated box 46 are not unique, and may be constructed as known
in the art. However, in combination with the throttle control
mechanism of the present invention, a unique control system 40 is
hereby provided.
[0027] As for those features particular to the inventive
controller, a throttle control assembly or subassembly 48 comprises
throttle grip or handle 42. The handle is mounted upon a shaft 50.
Multiple position locations 52 may be selected from which to secure
the handle to the shaft by mating pins 54 to best accommodate a
variety of uses or preferred positions. The adjustment holes may be
offset around the body of the shaft to allow for selecting a
position for the grip rotated around the Z-axis shown. To provide
clearance for one another, the adjustment locations may be provided
in a sort of "spiral staircase" arrangement as shown,
Alternatively, a smooth shaft may be provided against which one or
more setscrews are locked to secure position at different "heights"
along a Z-axis or different rotated "home" or "start" grip
positions around the shaft.
[0028] Shaft 50 may be received within a bracket 56 and be
supported by a bearing 58. Shaft 50 may be flexible, include a
flexible section (as described later in an alternative embodiment),
or include a U-joint (universal joint) 60 between a proximal
section "A" and a distal section "B". In the present embodiment, an
input bevel gear 62 driven by the handle meshes with an output
bevel gear 64 to transform the motion about the grip axis (Z-axis)
to motion useful for throttle control. Additional support bearings
58 may be provided for the distal section of the shaft.
[0029] Providing a flexible shaft, shaft section or a U-joint 60 as
shown allows for the grip to be adjusted about an axis Y in a plane
relative to the fixed body of the device. As noted, such an
adjustment offers improvement for user comfort in use as well as
the option of moving the grip out of the way for cockpit entry or
exit. The degree of adjustability provided may range from about 30
to about 90 degrees. By way of a pin 65 captured within a way 66,
or by some other stop means, travel may be limited to a desired
range. Detent features may also be provided to releasable secure or
give a tactile indication of movement or progression between
positions.
[0030] When a U-joint is employed for angular adjustment, the
system may employ a housing 68 to support the bracket 56 through
which shaft 50 is rotationally received. Housing 68 may be mounted
to a base 70. Regardless, pins or shoulder bolts 72 supported by
housing may be used to provide an axis of rotation for the
referenced angular adjustment of the grip relative to base 70
and/or plates 74 to which the base is affixed.
[0031] Adjustment of the grip assembly about an X-axis as shown is
also contemplated. Housing 68 and/or base 70 may be adjusted to a
desired position and locked down to one or more of the control body
plate(s) 74. In order to serve the desired support function, fixing
the position about the X-axis by pins, set screws, etc. is
important in order to avoid inadvertent movement or slippage of the
grip 42 in the direction of movement when a user is bracing
his/herself with it (possibly in combination with wheel 28).
Likewise, rotation about axis X should not be so great as to result
in turning axis Y far from horizontal. In other words, adjustment
around the X-axis should be limited to about +/-15 degrees.
[0032] Regarding grip 42 configuration, three buttons are shown
upon a canted head 76 of the handle. Button 78 operates the left
trim tab, button 80 manipulates outdrive in and out, and button 82
operates the right trim tab. The grip body is shaped to mimic the
natural curve of the human hand to provide better grip and allow
reach to actuate the buttons with the thumb while maintaining a
grip on the handle. Wiring is routed within hollows 84 of the grip
or as otherwise convenient.
[0033] As for throttle assembly output, the system is set to pull a
throttle cable 86 within a cable housing 88. The cable housing may
be attached to plate 74 by a clamp block 90. In a preferred
variation of the invention, the end of cable 86 is connected at a
block 92 to a slide 94. The cable may comprise a threaded end
fitting or section 96. A jam nut 98 may be provided to lock the
threaded section within threading inside block 92.
[0034] In the preferred arrangement, slide 94 forms part of a rack
and pinion assembly 100. Rack gear teeth 102 mesh with pinion gear
teeth 104. The pinion gear itself 106 may comprise a section or
sector of a full round gear. It may include lightening holes 108.
It preferably includes holes or depressions 110 to interface with a
spring loaded ball 112 to provide a detent means. The detent means
provides tactile feedback providing a user with an indication of
advancement across the range of throttle grip rotation.
Alternatively, a damped or smooth frictional feel to grip rotation
may be desired. Naturally, any type of action may be employed.
[0035] Regarding the action produced by grip rotation, reference to
FIG. 2B illustrates how rotation of bevel gear 62 turns bevel gear
64, that--in turn--rotates pinion 106 to translate rack/slider 94,
to push and pull throttle cable 86. Alternatively, pinion 104 could
be replaced by a cam or lever arm attached to the throttle cable.
Other output options exist as well. In any case, at some stage,
output from the second bevel gear drives cable pull.
[0036] Another noteworthy option concerns the manner in which the
throttle control and/or gear selector assembly is installed in a
boat. The combined unit 40 may simply be mounted to existing boat
hardware or to custom brackets using mounting bosses 114.
Alternatively, an existing gear selector setup may be employed and
only the throttle control section 48 of the system retrofitted to
the existing setup. Still further, the system may be integrated
into the original control design of a boat. In which case,
significant variation to the configuration of at least the device
housing is contemplated. Still further, any boat may be modified by
supplying a custom combing or wall insert to better accommodate a
stock throttle control system according to the present invention.
Such a wall insert to the boat would allow a user to better recess
the subject control housing or box. It is also contemplated that
the control housing can be adapted to be mounted in a seat, bolster
or on the floor of the boat. In these arrangements, the control
housing can be located towards the center of the boat, or outboard
of the driver as shown in FIG. 1C.
[0037] Another aspect of the invention concerns the manner in which
cable pull from the control side of systems is handled at the
engine side. The cable can actuate the motor throttle in a
conventional manner. However, FIG. 3 shows a more preferred
approach where a transfer mechanism 150 according to the present
invention operates an engine throttle shaft 152. Here, cable 86 is
affixed to throttle rack 154. As the rack is pulled by the throttle
cable, rack teeth 156 engage throttle pinion gear teeth 158,
causing throttle pinion gear 160 to rotate. The throttle pinion
gear is affixed to throttle shaft 152 by a setscrew, a splined
connection or other conventional means. Throttle shaft 152 may be
affixed to butterfly valve 162. As the butterfly valve position is
open, airflow to the engine is increased, resulting in increased
combustion in the engine, and higher boat speed. An extension
spring 164 may be provided in the system to bias cable pull and
help return the rack and pinion to its previous configuration when
the cable is "pushed" within the housing. The system in FIG. 3 is
especially advantageous for use with the system as illustrated in
FIGS. 2A and 2B because it offers a 1:1 correspondence of user
input to engine throttle action.
[0038] As indicated above, a flexible shaft may be utilized to
transmit torsional movement about the Z-axis from throttle grip 42
to an engine throttle, while permitting shaft 50 to be adjusted
about the X and Y axes shown in FIGS. 2A and 2B. An example of such
an alternative embodiment will now be described with reference to
FIGS. 4A-4D.
[0039] Referring first to FIGS. 4A and 4B, an embodiment is shown
that is similar to that of FIGS. 2A and 2B. In the alternative
embodiment of FIGS. 4A and 4B, controller grip 42 is mounted on
shaft 50 as previously described. Shaft 50 in turn is rotably
mounted to shaft bracket 56 with bearing 58, as shown in FIG. 2B.
One end of a flexible shaft 170 is attached to the lower end of
shaft 50, such as with one or more set screw 172 mounted in a
flexible shaft coupling 174. The other end of flexible shaft 170 is
attached to rotating arm 176 at its pivot point. The distal end 178
of arm 176 is coupled to throttle cable 86.
[0040] When grip 42 is rotated clockwise about the Z-axis, the
rotary motion is transmitted from shaft 50 to arm 176 by flexible
shaft 170. This motion causes the distal end 178 of arm 176 to move
in the fore direction, which pulls throttle cable 86 forward with
respect to cable housing 88. Conversely, when grip 42 is rotated
counter-clockwise about the Z-axis, flexible shaft 170 rotates in
the opposite direction. This motion causes the distal end 178 of
arm 176 to move in the aft direction, pushing throttle cable 86
rearward with respect to cable housing 88. The pulling and pushing
on throttle cable 86 serves to increase and decrease, respectively,
the throttle of the boat engine, such as described above in
reference to FIG. 3.
[0041] In this exemplary embodiment, the lower end of flexible
shaft 170 may be directly connected to arm 176 with a coupling
similar to coupling 174 at the upper end. Alternatively, the lower
end of flexible shaft 170 can be affixed within an opening of a
transfer shaft 180, as shown in FIG. 4B, such as with one or more
set screws. Shaft 180 may be rotably attached to plate 74. Arm 176
can be attached to the opposite end of shaft 180, such as with a
pin 182.
[0042] Referring now to FIGS. 4C and 4D, the operation of rotating
arm 176 and throttle cable 86 are more clearly shown. Cable housing
88 may be secured from longitudinal movement by pivot bracket 184.
In this example, clamp screw 186 adjustably secures cable housing
88 to pivot bracket 184. Pivot bracket 184 in turn is pivotably
secured to plate 74 with shoulder bolt 188. With this arrangement,
pivot bracket 184 and the end of cable housing 88 are allowed to
pivot around shoulder bolt 88 as arm 176 is moved between the aft
position shown in FIG. 4C and the fore position shown in FIG. 4D.
This alleviates throttle cable 86 from bending or binding in its
housing 88 as the distal end 178 of arm 176 rotates through the
bottom of its travel arc.
[0043] As with the embodiment depicted by FIGS. 2A and 2B, the
embodiment depicted by FIGS. 4A-4D allows the longitudinal Z-axis
of grip 42 to be rotated about the X-axis (fore and aft) and about
the Y-axis (pivoting up or down), as described above. In this
embodiment, the orientation of the longitudinal Z-axis can also be
locked in place after adjustments about the X and Y axes, as also
described above.
[0044] As can be seen by comparing FIGS. 4A and 4B with FIGS. 2A
and 2B, the use of flexible shaft 170 and rotating arm 176 permits
various components shown in FIGS. 2A and 2B to be eliminated, such
as universal joint 60, bevel gears 62 and 64, shaft 50B, bearings
58, slide 94, rack 102 and pinion gear 106. These components are
relatively complex, so their elimination can increase reliability
of control system 40 and reduce its size and cost. In alternative
embodiments, some or all of these components can be used in
combination with a flexible shaft. For example, rotating arm 176 of
FIGS. 4A-4D can be replaced with a pinion gear 106 as part of a
rack and pinion assembly 100, similar to that of FIG. 2B, with the
rack 102 mounted on a horizontal slide 94. Alternatively, just the
detent means of pinion gear 106 (i.e. holes or depressions 110 and
a spring loaded ball 112) can be incorporated into arm 176 and
plate 74, or provided elsewhere, to provide tactile feedback to a
user with an indication of advancement across the range of throttle
grip rotation.
[0045] Referring to FIG. 4B, a flexible shaft arrangement should be
chosen so that the bend radius of flexible shaft 170 is not so
small as to cause binding or excessive stress to flexible shaft 170
in any orientation of grip handle 42. Preferably, the bend radius
is about three or four inches. Flexible shaft 170 can be bare, as
shown in FIGS. 4A and 4B, or can be jacketed with a sleeve or
housing. If a jacketed flexible shaft is employed, one or both ends
are preferably secured to surrounding structures so that only the
core of the flexible shaft rotates as grip 42 is twisted. A
jacketed shaft can protect the shaft core from harsh marine
environments. A jacketed shaft may also be able to traverse tighter
spaces within the throttle control assembly 48' without rubbing on
adjacent parts. By securing one or more midpoints of a longer
jacketed shaft, excessive "helixing" or side-to-side movement can
be eliminated, thereby creating a more responsive throttle system.
Preferably, the length of flexible shaft 170 is about six inches.
An example of a suitable flexible shaft that can be used is part
number FR187SMRAB00600 manufactured by S.S. White Technologies,
Inc., Piscataway, N.J. (www.sswhite.net).
[0046] According to an aspect of yet another embodiment of the
present invention, the rotational motion of flexible shaft 170 need
not be converted into a linear push-pull motion at the throttle
control assembly 48'. Rather, a flexible shaft may be run directly
from throttle grip 42 to the boat engine or engine compartment.
There the rotational motion may be converted into linear motion
with a rotary arm similar to that shown in FIGS. 4C and 4D, a rack
and pinion assembly or other suitable mechanism. The rotational
motion of grip 42 need not ever be converted into linear motion,
but can instead be coupled directly or through reduction gearing to
throttle shaft 152 to drive the rotational movement of a butterfly
valve, such as shown in FIG. 3. Such an arrangement can reduce the
cost and complexity of a throttle system. Additionally, it can
provide direct control of the engine throttle without the backlash
that can accumulate in other throttle systems, particularly after
various components begin to wear. If a flexible shaft is run
between grip 42 and the engine throttle, the flexible shaft should
have high torsional rigidity to preserve responsiveness, and low
friction for ease of operation. Biasing a long flexible shaft in
one direction can also improve responsiveness.
[0047] According to an aspect of still another embodiment of the
present invention, switches 78, 80 and 82 atop grip 42' can be
arranged in a fan-like manner, as best shown in FIG. 5. With such
an arrangement, a user's thumb can more easily travel from one
switch to another. Preferably, the angle formed between adjacent
switches is between about 1 and 10 degrees. More preferably, the
angle is between about 2 and 7.5 degrees. Most preferably, the
angle is about 5 degrees. Two, three or four switches can be used
atop grip 42' in this embodiment of the invention. As indicated
above, each switch or button preferably has a momentary forward
position, a momentary rearward position and a neutral center
position.
[0048] Rather than being flat, top surface 190 may be arcuate as
shown in FIG. 5 to more closely match the arcuate movement of a
user's thumb. Preferably the arc of surface 190 has a radius
between about 1 and 36 inches, more preferably between about 2 and
12 inches, and most preferably the radius is about 8 inches.
Additionally, top surface 190 may be canted as shown with respect
to the longitudinal Z-axis of the grip shaft 50. Preferably the
centerline of surface 190 is canted between about 10 and 60
degrees, more preferably between about 20 and 40 degrees, and most
preferably about 30 degrees.
[0049] As for additional details pertinent to the present
invention, materials and manufacturing techniques may be employed
as within the level of those with skill in the relevant art. The
same may hold true with respect to method-based aspects of the
invention in terms of additional acts commonly or logically
employed. Also, it is contemplated that any optional feature of the
inventive variations described may be set forth and claimed
independently, or in combination with any one or more of the
features described herein. Likewise, reference to a singular item,
includes the possibility that there are plural of the same items
present. More specifically, as used herein and in the appended
claims, the singular forms "a," "and," "said," and "the" include
plural referents unless the context clearly dictates otherwise. It
is further noted that the claims may be drafted to exclude any
optional element. As such, this statement is intended to serve as
antecedent basis for use of such exclusive terminology as "solely,"
"only" and the like in connection with the recitation of claim
elements, or use of a "negative" limitation. Unless defined
otherwise herein, all technical and scientific terms used herein
have the same meaning as commonly understood by one of ordinary
skill in the art to which this invention belongs. The breadth of
the present invention is not to be limited by the subject
specification, but rather only by the plain meaning of the claim
terms employed.
* * * * *