U.S. patent number 3,865,063 [Application Number 05/424,290] was granted by the patent office on 1975-02-11 for electrical steering system for boats.
This patent grant is currently assigned to Arens Controls, Inc.. Invention is credited to Calhoun Norton.
United States Patent |
3,865,063 |
Norton |
February 11, 1975 |
ELECTRICAL STEERING SYSTEM FOR BOATS
Abstract
There is disclosed a control system for electronically
controlling a boat powered by a conventional twin screw
inboard-outboard drive system. The boat is maneuvered by a
plurality of reversible direct current motors which are controlled
through a complex electronic circuit system by a portable control
box. The portable control box is disengageably connected to the
electronic system so that the boat may be maneuvered from any
position thereon.
Inventors: |
Norton; Calhoun (Tequesta,
FL) |
Assignee: |
Arens Controls, Inc. (Evanston,
IL)
|
Family
ID: |
26897029 |
Appl.
No.: |
05/424,290 |
Filed: |
December 13, 1973 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
201708 |
Nov 24, 1971 |
|
|
|
|
25874 |
Apr 6, 1970 |
3651779 |
|
|
|
Current U.S.
Class: |
114/144R; 74/335;
114/157; 318/673; 440/53; 440/86; 327/576; 74/480B; 318/588;
318/675; 440/87; 477/6 |
Current CPC
Class: |
B63H
25/24 (20130101); G05D 3/1481 (20130101); Y10T
74/19251 (20150115); Y10T 477/27 (20150115); Y10T
74/20232 (20150115) |
Current International
Class: |
B63H
25/06 (20060101); B63H 25/24 (20060101); G05D
3/14 (20060101); B63h 025/24 () |
Field of
Search: |
;74/335,48B
;114/144R,157 ;115/18R,18E,35,37 ;180/79.1
;192/.096,.098,48.2,51,84R,142R ;318/588 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Halvosa; George E. A.
Assistant Examiner: Kunin; Stephen G.
Attorney, Agent or Firm: Olson, Trexler, Wolters, Bushnell
& Fosse, Ltd.
Parent Case Text
This is a Divisional Application of Ser. No. 201,708 filed Nov. 24,
1971 now abandoned which, in turn, was a Divisional Application of
Ser. No. 25,874 filed Apr. 6, 1970 now U.S. Pat. No. 3,651,779.
Claims
The invention is claimed as follows:
1. In a control system for a boat having engine means, drive means
and clutch means for selectively connecting the engine means to the
drive means, the combination comprising: a clutch actuating motor
connected to the clutch means for moving the same between engaged
and disengaged positions when connecting and disconnecting the
engine means and the drive means, three position switch means
selectively actuated to forward, neutral, and reverse positions,
rotational switch means having contacts coupled between said three
position switch means and said clutch actuating motor to cooperate
with said three position switch means for running said motor in one
direction when said three position switch means is in the forward
position and for running said motor in the opposite direction when
said three position switch means is in the reverse position, and
for running said motor in either said one direction or said
opposite direction when said three position switch means is in the
neutral position, drive means connected between said clutch
actuating motor and said rotational switch means for rotating the
same to a position where the contacts thereof are disconnected from
said clutch actuating motor to stop the motor selectively at the
forward, neutral, and reverse positions, and condition sensing
means connected in circuit with said three position switch means to
allow enabling of said clutch actuating motor only when a throttle
lever associated with the engine means is in a position to have the
engine means running at idle speed, said condition sensing means
including time delay switch means to provide sufficient time after
the throttle has been moved to the idle position to allow the
engine speed to completely return to the idle speed.
2. In the control system of claim 1 wherein said condition sensing
means includes switch contacts connected in series with said three
position switch means.
3. In the control system of claim 1 further including first and
second relay coils connected to first and second groups of contacts
of said rotational switch means, each of said relay coils having
contacts, one relay contact connected to one end of said clutch
actuating motor and the other relay contact connected to the other
end of said clutch actuating motor, whereby energization of one or
the other of said relay coils will cause energization of said
clutch actuating motor.
Description
This invention relates generally to a control system for
maneuvering a boat, and more particularly to an electronic control
system for maneuvering a boat.
In the past, steering arrangements for boats were disclosed in
accordance with my own U.S. Pat. No. 3,294,054 which shows a
mechanically coupled steering system without the use of electronic
controls. Although the system therein disclosed provides an
excellent steering mechanism for facilitating maneuvering of the
boat, it has been found that by utilizing an electronic control
system, as disclosed hereinafter, the ability to maneuver a boat is
enhanced. It has also been found that boat maneuverability can be
controlled from any position on the boat whereas such a feat is not
possible by utilizing a mechanically coupled system by itself.
Accordingly, a general object of the present invention is to
provide a novel electronic control system for maneuvering a
boat.
Another object of the present invention is to provide an electronic
control system for maneuvering a boat wherein maneuvering can be
accomplished from any desired position.
A more specific object of the present invention is to provide an
electronic control system for controlling the maneuverability of a
boat wherein the clutch, throttle, and steering mechanism of the
drive system can be independently regulated from various remote
positions.
A further object of the present invention is to provide novel
electronic control circuits for the control of the clutch, throttle
and steering mechanisms of a boat drive system.
Other objects and advantages of the present invention will become
apparent from the following description taken in conjunction with
the accompanying drawings, wherein:
FIG. 1 is a block diagram of the electronic control system for
controlling the maneuverability of a boat powered by a twin screw
inboard--outboard drive system;
FIG. 2 is a block diagram of the electronic control circuit for
controlling the throttles and steering of the boat;
FIG. 3 is a schematic diagram of the electronic control circuit for
controlling the steering of the boat;
FIG. 4 is a schematic diagram of the direct current reversible
motors used in conjunction with the electronic control circuit of
FIG. 3 for controlling the steering of the boat;
FIG. 5 is a schematic diagram of the electronic control circuit and
direct current reversible motor for controlling the throttles of
the boat; and,
FIG. 6 is a schematic diagram of the electronic control circuit and
direct current reversible motor for controlling the clutch
mechanisms of the boat.
Referring now more specifically to the drawings and particularly to
FIG. 1, the rear end section of a boat 10 is shown, conventionally
powered by a twin screw inboard--outboard drive system designated
generally by the numerals 12 and 14 although it is to be understood
that conventional outboard engines could also be used. An
electronic control system designated generally by the numeral 16
electronically controls the maneuverability of the boat 10 in the
same manner as the boat disclosed in my U.S. Pat. No. 3,294,054, is
maneuvered but with a higher degree of accuracy. For a discussion
of the particular maneuvering positions and the various forces
required for these respective positions, reference is made to the
above mentioned patent.
The inboard--outboard drive system 12 is positioned on the left or
port side of the boat and includes an engine 18 mounted within the
boat providing the power for a port outboard drive unit 20
conventionally mounted on the boat transom at the rear or stern of
the boat. A movable throttle arm 21 co-operates with the engine 18
for varying the power output of the engine from no power or idle
power when the throttle arm is in the position as indicated in
solid lines to full power when the throttle arm is positioned as
indicated in dotted lines.
The outboard drive unit 20 includes a propeller 22 mounted on the
end of a propeller shaft (not shown) which extends in a generally
horizontal position rearwardly with respect to the boat transom. A
tiller or steering lever 24 is provided for swinging the drive unit
to the left or right about a generally vertical pivot 26, as viewed
in FIG. 1, to change the angle of thrust of the propeller with
respect to a longitudinal axis 28 of the boat. The extreme
positions, both left and right, of the outboard drive unit 20 are
indicated by dotted lines in FIG. 1. An engageable clutch member 30
is provided for engaging and disengaging the engine 18 and outboard
drive unit 20. As indicated in FIG. 1, the clutch can be positioned
to the far left for engaging the engine and outboard drive unit
wherein the propeller 22 is driven in one direction for providing
forward power to the boat 10. The propeller is driven in an
opposite direction for providing rearward power to the boat 10 by
positioning the clutch member 30 to the far right and finally,
positioning the clutch intermediate the two about described extreme
positions disengages the motor and drive unit.
The inboard--outboard drive system 14 is positioned on the right or
starboard side of the boat and includes an engine 18a mounted
within the boat providing the power for a starboard outboard drive
unit 20a mounted on the boat transom at the rear or stern of the
boat. The inboard--outboard drive system 14 is structurally and
functionally exactly the same as the inboard--outboard drive system
12 and therefore like components are designated with like numbers
with an additional suffix a indicating the components of the drive
system 14.
The maneuverability of the boat 10 is dependent upon three factors,
firstly, the physical positioning of the propellers 22 and 22a with
respect to the longitudinal axis 28 of the boat, secondly, the
amount of power delivered by the engines 18 and 18a which is
determined by the positions of throttle arms 21 and 21a, and
thirdly, by the direction propellers 22 and 22a are driven which is
dependent upon whether the clutches 30 and 30a engage their
respective engine and drive unit in a forward or reverse manner. As
stated above, reference can be made to my U.S. Pat. No. 3,294,054,
for a detailed description of the various maneuvering positions
utilizing these factors.
For each inboard--outboard drive system 12 and 14, the electronic
control system 16 provides a steering motor assembly 32 and 32a
respectively, a throttle motor assembly 34 and 34a respectively,
and a clutch motor assembly 36 and 36a respectively. The steering
motor assemblies 32 and 32a control the positioning of their
respective drive units 20 and 20a as described in more detail
hereinafter. The throttle motor assemblies 34 and 34a are used to
position their respective throttle arms 21 and 21a for controlling
the power output of their respective engines 18 and 18a and the
clutch motor assemblies 36 and 36a are provided for positioning
their respective clutch members 30 and 30a for controlling the
engaging status of their respective engine and outboard drive
units.
The electronic control 16 also includes electronic control
circuitry, described in detail hereinafter, positioned within a
control panel 38 which may be mounted on boat 10 in any convenient
location. The control circuitry is electrically connected to the
above described motor assemblies via conduits 40 for controlling
the motor assemblies as described below. Additional electronic
control circuitry co-operating with the circuitry within control
panel 38 is located within a portable control box 42. The control
circuitry within the control box may be disengageably connected to
the control circuitry within control panel 38 for co-operating
therewith. This is accomplished by an electrical cord and plug 44
which co-operates with a socket 46 for connecting and disconnecting
the electronic circuitry in control panel 38 and portable control
box 42. This disengageable feature allows the operator of boat 10
to maneuver the boat from any position thereon merely by supplying
an appropriate extension cord (not shown) or if desired by
providing additional sockets located in various positions on the
boat and connecting the electronic circuitry within control panel
38 to those sockets.
The steering motor assembly 32 includes a reversible direct current
motor 48 and a piston assembly 50 mechanically coupled to the
output of reversible motor 48 for driving a piston or actuator 52
of the piston assembly 50. The piston 52 is driven from a retracted
position as indicated by solid lines in FIG. 1 to an extended
position as indicated in dotted lines when the reversible motor 48
is forwardly driven and back to its retracted position when the
reversible motor is reversely driven. It is to be understood that
the reversible direct current motor and the piston assembly are
both conventional and conventionally coupled to each other so as to
provide the above described results and therefore will not be
discussed in further detail. The free end of piston 52 which may be
a gear driven rack is mechanically connected to the steering lever
24 of the port outboard drive unit 20 by means not shown so as to
drive the outboard drive unit and corresponding propeller 22 from
the extreme right as viewed in FIG. 1 when the piston is in its
extended position to the extreme left when the piston is in its
retracted position.
A steering motor assembly 32a which is both structurally and
functionally identical to the steering motor assembly 32 is
mechanically coupled to the steering lever 24a of the starboard
outboard drive unit 20a in the same manner as steering motor
assembly 32 is coupled to steering lever 24. The reversible direct
current motor, piston assembly, and actuator of the steering motor
assembly 32a are designated by numerals 48a, 50a, and 52a
respectively. It is to be noted that when the actuator 52a is in
its extended position as indicated by dotted lines, the starboard
outboard drive unit 20a and its corresponding propeller 22a are
positioned to the right as viewed in FIG. 1. This is identical as
that described with respect to port outboard drive unit 20. It is
to be understood that the piston 52a may be easily coupled to the
steering lever 24a in such a manner so as to have the propeller 22a
positioned to the left when the piston is in its extended
position.
The throttle motor assemblies 34 and 34a are likewise structurally
and functionally equivalent to the steering motor assembly 32, the
reversible direct current motor, piston assembly, and actuator of
throttle motor assembly 34 being designated by numerals 54, 56 and
58 respectively while the reversible direct current motor, piston
assembly, and actuator of the throttle motor assembly 34a being
designated by numerals 54a, 56a and 58a respectively. The free end
of piston 58 or rack is mechanically connected to the throttle arm
21 of engine 18 so as to drive the throttle arm 21 from its
position as indicated in solid lines when the actuator is in its
retracted position to a position as indicated in dotted lines when
the actuator is in its extended position. As stated above, when the
throttle arm is in its solid lined position, the engine 18 merely
provides idle power and when the throttle arm is in its dotted
lined position, the engine provides full power. It is to be
understood that the engine power continuously increases as the
throttle arm is driven from its solid lined position to its dotted
lined position. The actuator 58a is mechanically coupled to the
throttle arm 21a in the same manner for controlling the power
output of engine 18a.
The clutch motor assemblies 36 and 36a are also both structurally
and functionally identical to steering motor assembly 32 and
include respective reversible direct current motors 60 and 60a,
piston or rack assemblies 62 and 62a, and actuators 64 and 64a. The
free end of actuator 64 is mechanically connected to the engageable
clutch member 30 for driving the clutch member from its far left
position, as viewed in FIG. 1, when the actuator is in its
retracted position to the far right when the actuator is in its
extended position and in an intermediate position when the end of
the actuator is intermediate its retracted and extended positions.
As stated above these three clutch positions represent forward
engagement of the outboard drive unit 20 and engine 18, reverse
engagement, and disengagement. The actuator 64a is mechanically
coupled to the engageable clutch member 30a so as to provide the
same function with respect to the inboard--outboard drive system 14
as actuator 64 provides with respect to inboard--outboard drive
system 12.
Now that a sufficient description has been given of each component
required for maneuvering boat 10 attention is directed to portable
control box 42 for a discussion dealing with the control of each of
the above described components for electronically controlling the
maneuverability of boat 10. It is to be understood that each
individual control mechanism on portable control box 42 is
appropriately connected to the electronic circuitry required to
control the various components as described above and that this
electronic circuitry will be described in great detail
subsequently.
The portable control box includes a steering wheel 66 and a switch
67 which may be referred to as a maneuvering switch. This switch is
a 2-position switch, one position being the "cruise" position and
the other position being the "maneuvering" position. The steering
wheel 66 is appropriately coupled to the electronic circuitry so as
to drive the pistons 52 and 52a of steering motor assemblies 32 and
32a respectively when the steering wheel is turned either clockwise
or counter-clockwise as viewed in FIG. 1. This, of course, causes
the outboard drive units 20 and 20a respectively to pivot about
vertical pivots 26 and 26a.
When the maneuvering switch 68 is in the cruise position, the
electronic circuitry is such that the outboard drive units 20 and
20a are positioned parallel to each other and remain parallel to
each other when the steering wheel is turned. That is to say, for
example, when the steering wheel is turned clockwise the outboard
drive units will concurrrently pivot to the right as viewed in FIG.
1 and will pivot to the left when the steering wheel is turned
counterclockwise.
When the maneuvering switch is flipped into the maneuvering
position, a portion of the electronic circuitry is reversed as will
be described hereinafter. As a result, when the wheel is turned
clockwise both of the outboard drive units toe in, i.e.,
concurrently pivot towards each other, and will toe in until they
reach the maximum position which is about 45.degree. to the
longitudinal axis 28 of the boat 10 or at about 90.degree. with
respect to each other. This will also be the position at which the
steering wheel can no longer be turned clockwise. When the steering
wheel is turned counterclockwise until it can no longer be so
turned, the outboard drive units will toe out, i.e., concurrently
pivot away from each other until they reach their stop positions
which again are at about 45.degree. angles to the longitudinal axis
28 and at about 90.degree. with respect to each other.
The portable control box 42 also provides a pair of throttle levers
68 and 68a which are appropriately connected to the electronic
circuitry for driving throttle arms 21 and 21a respectively when
the throttle levers are moved in a forward and rearward direction.
Two clutch levers 70 and 70a are also provided, appropriately
connected to the electronic circuitry, for driving engageable
clutch members 30 and 30a respectively into positions described
above when the clutch levers are moved in upward and downward
directions.
When the maneuvering switch is in the cruise position, the boat is
steered and the throttles are actuated in the usual manner
obtaining conventional but precise results. When the maneuvering
switch is in the maneuvering position with the steering wheel
turned clockwise as far as it can go so that both drive units are
toed in, free maneuverability can be obtained. In this condition
and with both clutches engaged in the forward position, the boat
can be steered merely by differential operation of the throttle
levers 68 and 68a. In other words, if the right hand or starboard
throttle 70a is advanced relative to the port throttle 70 so that
engine 18a has greater output power than engine 18, the boat will
turn to the right. As stated above, this is explained and broadly
covered in U.S. Pat. No. 3,294,054.
When the drive units are toed in and with one engine engaged in
reverse and the other in forward, and with the throttle levers
actuated generally uniformly, the boat will turn about its center
of drag. In other words, the boat will turn completely around
within its own length. The direction of turn can be reversed by a
turn of the steering wheel completely counterclockwise so that the
drive units are toed out.
An interlock, which will be described with respect to FIG. 6, is
provided between the throttle electronic circuitry and the clutch
electronic circuitry so that the clutches cannot be shifted until
the throttles have been returned to the idle position. In addition,
a time delay electrical device is provided so that if the clutch
switches have been shifted from one position to the other while the
throttles are advanced no shifting will take place even when the
throttles are returned to the idle position until after a small
time delay which permits the engines to drop back to the correct
speed before actual shifting takes place.
It is to be noted that the above described control system is
adapted to be connected with the usual steering, throttle and gear
shift controls of conventional structures.
Turning to FIG. 2, a block diagram of the electronic control
circuit for controlling the throttles and steering of the boat is
shown. An adjustable input circuit 72 is connected across a 12 volt
direct current power supply (not shown) for developing a variable
differential signal. In the case of the electronic steering
circuitry the value of this differential signal is dependent upon
the position of steering wheel 66 of FIG. 1 while in the case of
the electronic throttle circuitry the differential signal value is
dependent upon the position of throttle levers 68 or 68a. This
differential signal is fed to an operational amplifier circuit 74
which both regulates and amplifies the differential signal. The
output of the operational amplifier circuit, which is connected to
a switching circuit 76, is referenced to a positive 6 volts and can
swing either positive or negative from that value depending upon
the sign of the differential input signal.
When for example, the steering wheel is turned in one direction the
differential input signal is increased thus swinging the output of
the operational amplifier circuit positive with respect to the
above mentioned reference. When the steering wheel is turned in the
opposite direction, the differential input signal is decreased
causing the output of the operational amplifier circuit 74 to drop
below the reference voltage. The output of switching circuit 76 is
electrically connected to a motor assembly circuit 78 which in the
case of the electronic steering circuit includes the two reversible
direct current motors 48 and 48a. When the output of the
operational amplifier circuit is positive with respect to the 6
volts reference, the switching circuit allows the reversible motors
to be forwardly driven for driving the outboard drive units 20 and
20a in one direction as described with respect to FIG. 1. When the
output of operation amplifier circuit 74 is below the six volts
reference, the switching circuit allows the reversible motors to be
reversely driven for driving the outboard drive units in an
opposite direction. As stated above, the switching circuit includes
a maneuvering switch which can adjust the switching circuit so as
to drive the reversible direct current motors in opposite
directions which causes the outboard drive units to be either toed
in or toed out as described with respect to FIG. 1.
Separate electronic control circuitry is provided for the throttles
and functions in the same manner as described above except that
each portion of the circuitry controls only one reversible direct
current motor included in motor assembly 78, that motor being
either reversible direct current motor 54 or 54a. When, for
example, the throttle lever 68 is repositioned this either
increases or decreases the value of the differential input signal
depending upon which direction the throttle lever was moved. This
variation in the differential input signal in turn either increases
or decreases the output of the operational amplifier circuit with
respect to its output reference voltage causing the switching
circuit to allow the reversible direct current motor 54 to be
driven in one direction or the other.
Turning to FIG. 3, a schematic view of an electronic control
circuit 79 for steering boat 10 is shown. The circuit includes a 12
volt direct current source 80, an adjustable input circuit 82
electrically connected across the power supply 80, an operational
amplifier circuit 84 electrically connected to the output of the
adjustable input circuit, and a switching circuit 86 electrically
connected to the output of the operational amplifier circuit.
The adjustable input circuit 82 includes a master potentiometer R5
and a slave potentiometer R6 forming a part of a bridge circuit 87
across power supply 80. The adjusting arm 83 of potentiometer R5 is
mechanically connected to the steering wheel 66 so as to be driven
by the steering wheel causing the voltage across R5 to vary when
the steering wheel is moved which in turn drives actuators 52 and
52a as described above. Potentiometer R6 likewise has an adjusting
arm 85 which is mechanically connected to the steering actuators 52
and 52a for varying the voltage across R6 in proportion to the
movement of the actuators as will be described hereinafter. Two
resistors R1 and R2 connected in series across power supply 80
divide the 12 volts supply so that 6 volts appear between resistors
R1 and R2 and at the top of potentiometer R6 which has one end
electrically connected intermediate resistors R1 and R2. A resistor
R7 having one end electrically connected to the other side of
potentiometer R6 with the other side of R7 connected to the
negative side of power supply 70 is provided so that the range of
voltage appearing across potentiometer R6 is about 3 volts. The
voltage range of potentiometer R5 is also three volts or less
depending upon the adjustment of potentiometers R3 and R4 which
also form part of bridge circuit 87. Each of the potentiometers R3
and R4 has a respective adjusting arm 86 and 88 electrically
connected to a respective end of potentiometer R5. The
potentiometers R3 and R4 are connected in series with the otherwise
free end of potentiometer R3 electrically connected intermediate R1
and R6 and the otherwise free end of potentiometer R4 electrically
connected through a resistor R19 to a point intermediate resistors
R7 and potentiometer R6. Potentiometers R3 and R4 are used to
adjust the range of travel of actuators 52 and 52a when
potentiometer R5 is moved from one extreme position to the other
which in turn is driven by moving steering wheel 66 as stated
above. The slave potentiometer R6 is mechanically connected to the
actuator in such a way that only about three turns of the ten turn
potentiometer are used for full range travel of the actuator. In
other words, the adjusting arm 85 will only move a distance equal
to three-tenths that of the entire distance of potentiometer R6
when the actuators 52 and 52a are moved from one extreme position
to the other as described with respect to FIG. 1. Therefore, about
seven-tenths of the resistance of the potentiometer R6 appears in
the circuit as if it were a fixed resistance. Resistor R19 is
provided within the bridge 87 to match this unvarying portion of
potentiometer R6. A resistor R8 has one end electrically connected
to the actuating arm 85 of potentiometer R6 and its otherwise free
end connected to the negative input terminal of an operational
amplifier 90 which will be described hereinafter. A resistor R9
electrically connects the adjusting arm 83 to the positive input
terminal of operational amplifier 90. The two resistors R8 and R9
are provided so as to utilize the voltages across potentiometers R5
and R6 as a differential input signal which is to be fed to the
input of operational amplifier 90.
The operational amplifier circuit 84 includes an operational
amplifier 90 having negative and positive input terminals
respectively designated by numerals 1 and 2, an output terminal
designated by the numeral 3 and additional terminals designated by
the numerals 4, 5, 6 and 7 respectively. The operational amplifier
circuit also includes an adjustable resistor R10 connected at one
end to the output terminal 3 of the operational amplifier 90 with
its otherwise free end connected intermediate resistor R8 and
negative input terminal 1. The resistor R10 provides conventional
negative feedback for the operational amplifier. The amplifier gain
is determined approximately by the values of resistors R8 and R10.
The operational amplifier 90 is a conventional RCA No. CA 3029 type
amplifier and reference is made to the RCA handbook RCA Linear
Integrated Circuits (technical series IC-41) for a detailed
discussion of the amplifier. It is to be understood, of course,
that other operational amplifiers providing the same function as
described below may be substituted therefor. A resistor R11 and a
capacitor C2 connected in series, are provided to form a phase
compensation network for the operational amplifier. This series
circuit has one end connected to terminal 4 of the operational
amplifier and its otherwise free end connected intermediate
resistors R1 and R2. The terminal 5 of the operational amplifier is
connected to the otherwise free end of resistor R11 and the
terminal 7 is connected to the negative side of power supply 80.
The output of the operational amplifier is referenced to a positive
six volts as discussed below and can swing either above or below
that value depending upon the sign of the differential input
signal. That is to say that the output of operational amplifier
depends upon whether the voltage across R9 is greater or less than
the voltage across R8. A resistor R18 is electrically connected at
one end intermediate resistor R9 and positive input terminal 2 of
the operational amplifier, the otherwise free end of resistor R18
being connected intermediate resistors R1 and R2. R18 has been
included in the circuit for the sake of completeness. In practice,
it has not been used and is not essential in this application.
The switching circuit 86 includes an NPN transistor Q1 and PNP
transistor Q2 each of which has its base connected to the output of
operational amplifier 90 and its emitter connected to the emitter
of the other transistor. The collector of transistor Q1 is
connected to the positive side of the power supply 80 through two
biasing resistors R12 and R13 while the collector of Q2 is
connected to the negative side of power supply 80 through biasing
resistors R14 and R15. The emitters of both transistor Q1 and Q2
are also connected intermediate resistors R1 and R2 so that the
emitters are maintained at 6 volts, the output reference voltage of
the operational amplifier 90 as referred to above. A second NPN
transistor Q3 is connected across the power supply 80 with its base
connected intermediate resistors R14 and R15, its emitter connected
to the negative side of the power supply, and its collector
connected to the positive side of the power supply through an
electromagnetic relay K1. A second electromagnetic relay K3 is
connected across the electromagnetic relay K1. It is to be
understood that the electromagnetic relays herein referred to, are
conventional relays having electromagnetic coils which when
energized open or close normally closed or opened associated
contact. When reference is made to the relay itself what is meant
is the electromagnetic coil. A second PNP type transistor Q4 is
also connected across the power supply 80 having its base connected
intermediate resistors R12 and R13, its emitter connected to the
positive side of power supply 80, and its collector connected to
the negative side of power supply 80 through an electromagnetic
relay K2. A fourth electromagnetic relay K4 is connected across
relay K2. The electromagnetic relays K1, K2, K3 and K4 are also
electrically tied to a wafer type switch 92 which may be actuated
by maneuvering switch 67 such that electromagnetic relay K3 is
electrically connected across K2 and that electromagnetic relay K4
is connected across K1 for reasons described below.
The transistor Q3 has a filtering circuit connected across its
collector and emitter comprising a capacitor C4 and resistor R17
connected in series while the transistor C4 has a filtering circuit
connected across its collector and emitter comprising capacitor C3
and resistor R16 connected in series. The electromagnetic relays
K1, K2, K3 and K4 have respective contacts K1', K2', K3' and K4'
which are electrically connected to reversible direct current
motors 48 and 48a and will be described with respect to FIG. 4.
The electronic control circuit 79 of FIG. 3 includes a capacitor C1
electrically connected across the resistors R1 and R2 so as to
prevent a drain of power from supply 80 when reversible direct
current motors 48 and 48a are initially energized as described
below. A diode D1 having its anode connected to the positive side
of the power supply 80 and its cathode connected to the remainder
of the electronic circuit 79 is provided to block the discharging
of capacitor C1 by the motor load. It also protects the circuit
against accidental application of the wrong polarity.
In operation, when the steering wheel 66 is maintained such that
the outboard drive units 20 and 20a are positioned parallel to the
longitudinal axis 28 of boat 10 equal voltages appear across
potentiometers R5 and R6 causing a differential input signal of
zero to appear at the input of operational amplifier 90. The
emitters of transistors Q1 and Q2 are therefore maintained at 6
volts reference causing the transistors to be in a nonconductive
state. This in turn prevents either of the transistors Q3 or Q4
from being in a conductive state. As long as the transistors Q3 and
Q4 remain in a nonconductive state, the electromagnetic relays K1,
K2, K3 and K4 remain in a de-energized condition which prevents the
reversible motors 48 and 48a from driving their respective outboard
drive unit as will be described with respect to FIG. 4.
When, for example, the steering wheel 66 is turned clockwise the
voltage across potentiometer R5 increases causing the bridged
circuit 87 to be unbalanced and thus a positive differential input
signal appears at the input of operational amplifier 90. This in
turn increases the output of the operational amplifier with respect
to its 6 volts reference causing transistor Q1 to conduct. With Q1
conducting, transistor Q4 is properly biased, allowing
electromagnetic relays K2 and K4 to be energized. As will be
described with respect to FIG. 4, this causes reversible motors 48
and 48a to be simultaneously driven in forward directions so that
their respective actuators 52 and 52a move to extended positions.
The outboard drive units 20 and 20a will in turn be pivoted to the
right as viewed in FIG. 1. When the steering wheel is no longer
turned, such that the voltage across potentiometer R5 is maintained
at a value greater than the voltage across potentiometer R6, the
adjusting arm 85 is repositioned by its mechanically connected
actuators 52 and 52a such that bridge circuit 87 is again balanced.
This in turn drives the differential input signal to a value of
zero causing the reversible motors 48 and 48a to be
de-energized.
Similarly, if steering wheel 66 is turned counterclockwise reducing
the voltage across potentiometer R5 a negative differential input
signal appears at the input of operational amplifier 90 causing Q2
and Q3 to conduct which in turn energizes electromagnetic relays K1
and K3 causing the reversible motors 48 and 48a to be driven such
that the outboard drive units 20 and 20a are pivoted to the left as
viewed in FIG. 1. When the steering wheel is no longer turned, the
potentiometer R6 is again repositioned such that a differential
input signal of zero appears at the input of operational amplifier
90 causing the reversible motors to be de-energized and stopping
outboard drive units 20 and 20a.
Turning to FIG. 4, the reversible direct current motor 48 has its
positive or forward side connected to electromagnetic relay contact
K2' and its negative or reverse side connected to electromagnetic
relay contact K1'. When the electromagnetic relays K1 and K2 are in
their de-energized state, the contacts K1' and K2' connect
reversible motor 48 to ground as indicated by a solid line
representation in FIG. 4. When the electromagnetic relay K2 is
energized, the contact K2' is moved to its dotted line position.
This connects the reversible motor 48 to a 12 volt direct current
source such that the motor is driven in a forward direction so as
to function as described above. When the electromagnetic relay K1
is energized, contact K1' is moved to its dotted line position such
that the reversible motor 48 is driven in a reverse direction.
Reversible motor 48a is electrically connected to a 12 volt DC
power supply in the same manner as reversible motor 48 such that
motor 48a is driven in a forward direction when electromagnetic
relay K4 is energized and in a reversed direction when
electromagnetic relay K3 is energized.
The above discussion assumes that maneuvering switch 67 is in its
"cruse" position. If the switch is thrown to its "maneuvering"
position causing electromagnetic relay K3 to be connected to K2 and
K4 to be connected to K1 the operation will be the same except that
motor 48a will be driven in an opposite direction from that of
motor 48. This in turn will cause a toeing in and toeing out of
drive units 20 and 20a as described with respect to FIG. 1.
It is to be understood that reversible direct current motors 48 and
48a may utilize their own electronic control circuit 79 as
described in FIG. 3. In such a case, a potentiometer R5 of each
circuit would be mechanically connected to the steering wheel 66
such that each of the potentiometer's actuating arms 82 would be
moved equally and simultaneously. It is to be further understood
that the 12 volt direct current power supply 80 may be used to
power the reversible motors 48 and 48a in addition to the
electronic circuitry of FIG. 3 rather than using separate power
supplies as indicated in FIG. 4.
Turning to FIG. 5, an electronic control circuit for the throttle
arm 21 is shown. This circuit functionally and structurally is
similar to that circuit disclosed with respect to FIG. 3 with
exceptions indicated below. Electrical components of the electronic
circuitry of FIG. 5 which are equivalent to those components of
FIG. 3 are designated with like numerals in addition to a suffix
a.
The first electrical difference between the two circuits is that
potentiometer R19' replaces resistors R19, R3 and R4. The
potentiometer R19 serves to limit the range of travel of actuator
58 for a given range of travel of the master potentiometer R5a. As
stated above, this function was provided by potentiometers R3 and
R4 of electronic control circuit 79 of FIG. 3. The actuating arm 96
of potentiometer R19' is electrically connected to the negative
side of power supply 80a through resistor R7a. A second difference
is that a zener diode D2 has been added, which diode is
electrically connected intermediate variable resistor R10 and input
terminal 1 of the operational amplifier 90. Thirdly, resistors R16
and R17 and capacitors C3 and C4 have been eliminated along with
resistor R18. Finally, electromagnetic relays K3 and K4 have been
eliminated so that the electronic circuit controls only one
reversible direct current motor which as shown in FIG. 5 is the
throttle reversible motor 54.
In operation, when the throttle lever 68 is maintained in its idle
position equal voltages appear across potentiometers R5 and R6
which as in the case of electronic control circuit 70 causes
transistors Q1, Q2, Q3 and Q4 to be off which in turn maintains
electromagnetic relays K1 and K2 in their de-energized state so
that reversible motor 54 is de-energized. When the throttle lever
is forwardly moved, the voltage across potentiometer R5 increases
so that reversible motor 54 is forwardly driven causing actuator 58
to drive throttle arm 21 as described with respect to FIG. 1. The
motor 54 is de-energized when the voltage across potentiometer R6
goes to a value such that the differential input signal appearing
at the input of operational amplifier 90 is equal to zero as in the
case of circuit 79. The reversible direct current motor 54 may be
reversed in the same manner as described with respect to the
electronic control circuit 79.
It is to be understood that a circuit equivalent to that described
with respect to FIG. 5 is provided for the throttle arm 21a and is
actuated in the same manner by throttle lever 68a.
Turning to FIG. 6, an electronic control circuit 100 for
controlling the engageable clutch member 30 as described in FIG. 1
is connected across a 12 -volt direct current power supply 102. The
electronic control circuit 100 includes a wafer shaped switch 104
which is mechanically coupled to the clutch actuating motor 60, of
the clutch motor assembly 36 so as to function as described below.
The wafer switch 104 has two conductive portions 106a and 106b each
of which substantially comprises a respective half of the wafer
switch. The conductive portions may be made from copper or like
conductive material. The wafer also has two wedge shaped insulating
or nonconductive portions 108a and 108b each of which extends from
an opposite outer edge of the wafer and meets at the center
thereof. The nonconductive portions separate the two conductive
portions 106a and 106b.
The electronic control circuit 100 also includes a three-position
switch 110 having three positions indicated by the letters F, N and
R respectively and a movement arm indicated by the numeral 112. The
point about which movement arm 112 pivots is electrically connected
to the negative side of power supply 102 through a switch 114 and a
timing switch 116. The switches 114 and 116 are operably connected
to the throttle lever 68 by means not shown and function in a
manner described below. The F or forward position of switch 110 is
slideably and electrically connected to the wafer switch 104 by tap
member 118. The tap 118 is positioned adjacent the lower left hand
quadrant of wafer switch 104 as viewed in FIG. 6 such that the tap
maintains contact with the wafer switch when the wafer switch is
rotated as described below. The R or reverse position of switch 110
is connected to the lower right quadrant of wafer switch 104 by tap
member 120 in the same manner as described with respect to tap
member 118. The N position of switch 110 is likewise slideably and
electrically connected to the wafer switch 104 by tap member 122.
The tap member 122 is positioned on the wafer switch intermediate
taps 118 and 120.
The electronic circuit 100 also includes electromagnetic relays K5
and K6 each of which has one end connected to the positive side of
power supply 102. The otherwise free side of electromagnetic relay
K5 is slideably and electrically connected to wafer switch 104 by
tap member 124 at a point adjacent to tap member 118. The otherwise
free side of electromagnetic relay K6 is likewise connected to
wafer switch 104 by tap member 126 which is positioned adjacent tap
member 120. Each of the electromagnetic relays, K5 and K6, have
respective contacts K5' and K6' which are connected respectively to
the forward and reverse sides of reversible direct current motor
60, reversible direct motor 60 being the motor for controlling the
engageable clutch member 30 as described in FIG. 1. The contacts
K5' and K6' connect reversible motor 60 to ground when their
respective electromagnetic relays are de-energized. This is
indicated by a solid line representation of K5' and K6' in FIG. 6.
The dotted line representation of contacts K5' and K6' indicate the
positions of these contacts when their respective electromagnetic
relays are energized and will control reversible motor 60 as
described below.
In operation, when the clutch lever 70 is positioned such that
engine 18 and outboard drive unit 20 are disengaged as described
with respect to FIG. 1, switch 110 which is mechanically coupled to
clutch lever 70 is positioned in its N position as seen in FIG. 6.
This disconnects both electromagnetic relays K5 and K6 from power
supply 102. As seen in FIG. 6 the wafer switch 104 is positioned
such that its nonconductive portion 108b is in contact with tap
member 122.
When it is desired to forwardly engage engine 18 and outboard drive
unit 20 the clutch lever 70 is positioned such that switch 110 is
in its F position. This closes the circuit through electromagnetic
relay K5 such that the current from power supply 102 will pass
through electromagnetic relay K5 and thereafter to the negative
side of the power supply through tap member 124, conductive portion
106a of wafer switch 104 and tap member 118, energizing
electromagnetic relay K5. This is, of course, assuming that
switches 114 and 116 are closed. These switches are coupled to
throttle lever 68, by means not shown, such that switch 114 is
closed only when the throttle lever is in its idle position and
switch 116 is energized at the same time so as to close its contact
a predetermined period of time after the throttle lever has been
positioned in its idle position. The reason for the time delay is
so that the engine 18 can drop back to its idle speed before actual
shifting takes place.
With electromagnetic relay K5 energized contact K5' is positioned,
as indicated in dotted lines so as to connect the forward side of
reversible motor 60 to a 12 -volt power supply. This drives
reversible motor 60 forwardly, as described in FIG. 1, for
forwardly engaging engine 18 and outboard drive unit 20. As the
motor 60 is forwardly driven, the motor drives its mechanically
connected wafer switch 104 so as to move in a counterclockwise
direction as viewed in FIG. 6 until nonconductive portion 108a
encompasses tap members 118 and 124. This disconnects the circuit
through electromagnetic relay K5, de-energizing electromagnetic
relay K5 and reversible motor 60.
If it is desired to reversely engage engine 18 and outboard drive
unit 20, clutch lever 70 is moved such that switch 110 is in its R
position for energizing electromagnetic relay K6. In such a
position, current from power supply 102 passes through
electromagnetic relay K6, tap member 126, conductive portion 106a
of wafer switch 104 which is now positioned under taps 120 and 126,
tap member 120 and ultimately to the negative side of power supply
102. This again is assuming that throttle lever 68 is positioned
such that switches 114 and 116 are closed. With electromagnetic
relay K6 energized, contact K6' is positioned as indicated in
dotted lines such that reversible motor 60 is reversely driven by
the 12 -volt power supply for appropriately driving mechanical
clutch member 30 as described with respect to FIG. 1.
As motor 60 is reversely driven, wafer switch 104 is driven
clockwise. When nonconductive portion 108b encompasses tap members
120 and 126, the circuit through electromagnetic relay K6 is again
opened de-energizing K6 and reversible motor 60. The engine 18 and
outboard drive unit 20 are now reversely engaged.
If it is finally desired to disengage the engine and drive unit,
clutch lever 70 is appropriately positioned such that switch 110 is
again in its N position so as to energize electromagnetic relay K5.
In this situation the current from power supply 102 passes through
electromagnetic relay K5, tap member 124, conductive portion 106 of
wafer switch 104 which now is positioned under the tap members 118,
122 and 124, tap member 122 and thereafter to the negative side of
power supply 102. This ultimately causes the wafer switch again to
be driven counterclockwise until nonconductive portion 108b is
positioned under tap member 122 for disconnecting the switch.
It is to be understood that an electronic control switch circuit
similar to that described with respect to FIG. 6 is provided for
the clutch controls of inboard-outboard drive system 14 and
actuated by clutch lever 70a.
While a particular embodiment of the invention has been shown, it
should be understood, of course, that the invention is not limited
thereto since many modifications may be made, and it is, therefore,
contemplated to cover by the appended claims any such modifications
that fall within the true spirit and scope of the invention.
* * * * *