Note: Descriptions are shown in the official language in which they were submitted.
E-1886
1 334359
MARlNE PROPULSION DEVICE TILT
LIMIT SWITCH
BACKGROUND OF THE INVENTION
The invention relates to marine propulsion-~devices,
and, more particularly, to means for limiting the upward
tilting movement of the propulsion unit of a marine propulsion
device.
A typical propulsion device, such as an outboard
motor, includes a propulsion unit mounted on the transom of a
boat for pivotal movement relative thereto about a generally
horizontal tilt asis. In may cases, pivotal movement of the
propulsion unit is controlled by a hydraulic cylinder-piston
assembly estending between a mounting bracket fixed to the
transom and either the propulsion unit or a swivel bracket.
Hydraulic fluid is selectively supplied to the opposite ends of
the cylinder by a pump.
Because of the wide variety of boat and outboard motor
combinations now possible, it is fairly common to have
interference between the boat and the propulsion unit of the
outboard motor when the propulsion unit is in its masimum
upward tilt position. This can result in damage to the boat
and/or the outboard motor.
It is known to provide a switch for disabling the pump
when the propulsion unit reaches the upper limit of its pivotal
movement. U. S. Patent No. 4,695,260 teaches the use of either
a pressure responsive switch in the hydraulic pressure line or
a limit switch for sensing when the hydraulic assembly is fully
estended.
- ~ -2- 1 3 3 4 3 5 9
Attention is also directed to U. S. Ferguson Patent
No. 4,605,375, issued August 12, 1986.
SUNNARY OF THE lNV~N l ION
The invention provides a marine propulsion device
comprising a transom bracket adapted to be fixedly mounted on
the transom of a boat, a propulsion unit mounted on the transom
bracket for pivotal movement relative thereto about a generally
horizontal tilt axis, an exte~hle and contractable
cylinder-piston assembly connected between the transom bracket
and the propulsion unit for pivoting the propulsion unit about
the tilt axis in response to extension and contraction of the
assembly, a pump for selectively and alternatively extending
and contracting the assembly, and means for disabling the pump
and thereby stopping pivotal movement of the propulsion unit in
response to the position of the assembly relative to one of the
transom bracket and the propulsion unit.
The invention also provides a marine propulsion
device comprising a transom bracket adapted to be fixedly
mounted on the transom of a boat, a propulsion unit mounted on
the transom bracket for upward and downward pivotal movement
relative thereto about a generally horizontal tilt axis,
operator actuatable means for pivoting the propulsion unit
about the tilt axis, which pivoting means includes an
extendable and contractible link connected between the transom
bracket and the propulsion unit, and adjustable means operable
independently of the operator actuatable means for stopping
upward pivotal movement of the propulsion unit, which
adjustable means includes a first member fixed relative to the
propulsion unit and a second member fixed relative to the
link.
~ ~3~ 1 3 3 4 3 5 9
The invention also provides a marine propulsion
device comprising a transom bracket adapted to be fixedly
mounted on a transom of a boat, a propulsion unit mounted on
the transom bracket for pivotal movement relative thereto about
a generally horizontal tilt axis, pivoting means for causing
pivotal movement of the propulsion unit about the tilt axis,
and means including a first member fixed relative to one of the
transom bracket and the propulsion unit and a second member
fixed relative to the pivoting means for stopping pivotal
..,ove..cnt of the propulsion unit in response to engagement of
the first and second members.
A principal feature of the invention is the provision
of a marine propulsion device comprising operator actuatable
means for pivoting a propulsion unit about a tilt axis, and
adjustable means operable independently of the operator
actuatable means for stopping upward pivotal movement of the
propulsion unit. This permits the maximum upward tilt position
of the propulsion unit to be adjusted so that the marine
propulsion device can be used with a variety of boat
constructions.
Another principal feature of the invention is the
provision of means for stopping upward pivotal ~ v~..cnt of a
propulsion unit in response to the position of the hydraulic
cylinder-piston assembly relative to the propulsion unit.
Another principal feature of the invention is the
provision of a member fixed to the hydraulic assembly, a member
fixed to the propulsion unit, and means for stopping upward
pivotal movement of the propulsion unit when the members
engage. This arrangement solves the problem of having little
space for mounting a limit switch between the mounting bracket
and the propulsion unit or swivel bracket.
~ -4- 1 3 3 4 3 5 9
Other features and advantages of the invention will
become apparent to those skilled in the art upon review of the
following detailed description, claims and drawings.
DESCRIPTION OF THE DRAWINGS
Fig. 1 is a side elevational view of a marine
propulsion device embodying the invention.
Fig. 2 is an enlarged, partial view of the marine
propulsion device.
Fig. 3 is a view similar to Fig. 2.
Fig. 4 is an enlarged view taken along line 4-4 in
Fig. 2.
Fig. 5 is a view taken along line 5-5 in Fig. 4.
Fig. 6 is a schematic view of the electrical and
hydraulic circuits of the marine propulsion device.
Before one embodiment of the invention is explained in
detail, it is to be understood that the invention is not
limited in its application to the details of construction and
the arrangements of components set forth in the following
description or illustrated in the drawings. The invention is
capable of other embodiments and of being practiced or being
carried out in various ways. Also, it is to be understood that
the phraseology and terminology used herein is for the purpose
of description and should not be regarded as limiting.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A marine propulsion device 10 embodying the invention
is illustrated in the drawings. While the illustrated marine
1 334359
propulsion device is an outboard motor, it should be understood
that the invention is applicable to other types of marine
propulsion devices, such as stern drive units.
The marine propulsion device 10 comprises (see Fig. 1)
a transom bracket 12 fi~edly mounted on the transom 14 of a
boat. The marine propulsion device 10 also comprises (see
Figs. 1-3) a swivel bracket 16 mounted on the transom bracket
12 for upward and downward pivotal movement relative thereto
about a generally horizontal tilt asis 18. The marine
propulsion device 10 further comprises (see Fig. 1) a
propulsion unit 20 mounted on the swivel bracket 16 for pivotal
movement relative thereto about a generally vertical steering
a~is 22 and for common pivotal movement therewith about the
tilt axis 18. The propulsion unit 20 includes a propeller 24
fixedly mounted on a propeller shaft 26, and an engine 28
drivingly connected to the propeller shaft 26 via a
conventional drive train (not shown).
The marine propulsion device 10 further comprises (see
Figs. 1 and 6) operator actuatable means 32 for pivoting the
propulsion unit 20 about the tilt a~is 18. Preferably, the
means 32 includes an extendable and contractable link connected
between the boat and the propulsion unit 20. In the preferred
embodiment, the link is a hydraulic cylinder-piston assembly 34
includinq (see Fig. 6) a cylinder 36 pivotally connected to the
transom bracket 12, a piston 38 slidably housed in the cylinder
36 so as to divide the cylinder into upper and lower chambers
40 and 42, respectively, and a piston rod 44 fixedly connected
to`the piston 38 and connected to the swivel bracket 16 for
_- -6-
1 334359
pivotal movement relative thereto about an axis 46 (Fig. 5).
The piston 38 has therein a relief valve (not shown) that
permits f luid f low f rom the upper chamber 40 to the lower
chamber 42 and thereby permits extension of the cylinder-piston
assembly 34 in the event the marine propulsion device 10
strikes an underwater obstacle. The upper end of the piston
rod 44 has thereon (see Figs. 2-5) an eyelet 48 having
therethrough a horizontally extending bore 50 (Fig. 5), and the
piston rod 44 is pivotally connected to the swivel bracket 16
by a pin 52 which extends through the bore 50 and which is
f ixedly connected to the swivel bracket 16. Extension of the
hydraulic assembly 34 causes upward pivotal movement of the
propulsion unit 20 and contraction of the hydraulic assembly 34
causes downward pivotal movement of the propulsion unit 20.
The operator actuatable means 32 also includes (see
Fig. 6) a reversible pump 54 connected to the cylinder chambers
40 and 42 via hydraulic conduits 56 and 58, respectively.
Conventional relief valves 60 and 62 connect the conduits 56
and 58 in order to permit fluid f low between the conduits 56
and 58 when the piston 38 tops out or bottoms out. The
operator actuatable means 32 also includes an electric motor 64
drivingly connected to the pump 54. The direction in which the
motor 64 drives the pump 54 is determined by the direction in
which current flows through the motor 64. More particularly,
the motor 64 has two leads or contacts 66 and 68, and the motor
64 drives the pump 54 in one direction when the lead 66 is
connected to a source of electric power and drives the pump 54
in the other direction when the lead 68 is connected to a
~7~ 1 334359
source of electric power. The pump 54 and motor 64 are
conventional and will not be described in further detail.
The operator actuatable means 32 also includes (see
Fig. 6) an electrical circuit 70 permitting selective operator
actuation of the motor 64. The circuit 70 includes a manually
operable three-position switch 72 having three leads 74, 76 and
78. The middle lead 74 is connected to a suitable source of
electric power, such as a battery 80 for the marine propulsion
device 10. When the switch 72 is in its middle or "off"
position, the battery 80 is connected to neither of the leads
76 and 78. When the switch 72 is in its second or "up"
position, the battery 80 is connected to the lead 76. When the
switch 72 is in its third or "down" position, the battery 80 is
connected to the lead 78. The circuit 70 also includes an "up"
relay 82 having three leads 84, 86 and 88. The relay 82
operates to connect the battery 80 to the lead 86 when the lead
84 is connected to a source of electrical power, and operates
to connect the lead 86 to the lead 88 when the lead 86 is not
connected to a source of electrical power. As shown in Fig. 6,
the lead 84 is connected to the lead 76 of the switch 72, the
lead 86 is connected to the lead 66 of the motor 64, and the
lead 88 is connected to ground. The electrical circuit 70 also
includes a "down" relay 90 that is substantially identical to
the "up" relay 82 and that includes leads 94, 96 and 98
respectively corresponding to the leads 84, 86 and 88 of the
up" relay 82. The lead 94 is connected to the lead 78 of the
switch 72, the lead 96 is connected to the lead 68 of the motor
64, and the lead 98 is connected to ground.
-8-
1 334359
The electrical circuit 70 operates as follows. When
the switch 72 is in its ~off~ position, the motor 64 is
disconnected from the battery 80 and does not drive the pump
54. When the switch 72 is in its ~up~ position, current flows
from the battery 80 to the lead 66 of the motor 64 via the
switch leads 74 and 76 and the ~up~ relay leads 84 and 86, and
current flows from the motor lead 68 to ground via the ~down~
relay leads 96 and 98. This causes the motor 64 to drive the
pump 54 in the direction providing fluid flow to the lower
cylinder chamber 42. When the switch 72 is in its ~down~
position, current flows from the battery 80 to the motor lead
68 via the switch leads 74 and 78 and the ~down~ relay leads 94
and 96, and current flows from the motor lead 66 to ground via
the ~up~ relay leads 86 and 88. This causes the motor 64 to
drive the pump 54 in the direction causing fluid flow to the
upper cylinder chamber 40.
The marine propulsion device 10 further comprises (see
Figs. 2-5) adjustable means 100 operable independently of the
operator actuatable means 32 for stopping pivotal movement of
the propulsion unit 20. The means 100 preferably includes
means for stopping upward pivotal movement of the propulsion
unit 20 in response to the position of the hydraulic assembly
34 relative to the swivel bracket 16 or propulsion unit 20.
While various suitable means can be employed, in the preferred
embodiment, such means includes means 102 for stopping upward
pivotal movement of the propulsion unit 20 when the hydraulic
assembly 34 reaches a predetermined angle relative to the
swivel bracket 16 or propulsion unit 20. While various
-9- 1 3 3 4 3 5 9
suitable stopping means 102 can be used, in the illustrated
construction, the means 102 includes (see Figs. 2, 3 and 6) a
first member or electrical switch 104 (shown schematically in
Fig. 6) which is mounted on the swivel bracket 16 (and thus is
fixed relative to the propulsion unit 20) and which is
electrically connected to the motor 64 so that opening of the
switch 104 disables the motor 64 and thereby disables the pump
54. More particularly, the switch 104 is biased closed and is
connected in series between the switch lead 76 and the ~up"
relay lead 84, so that opening of the switch 104 prevents
operation of the motor 64 to cause extension of the
cylinder-piston assembly 34. As shown in Figs. 2 and 3, the
switch 104 includes a housing 106 ~i~edly mounted on the swivel
bracket 16, and a plunqer 108 a~ially movable relative to the
housing 106 between an inward or open position (shown in
phantom in Figs. 2 and 3) and an outward or closed position
(shown in solid lines in Figs. 2 and 3). The plunger 108 is
biased outwardly or toward the closed position. In alternative
embodiments, the housing 106 can be mounted on the swivel
bracket 16 such that the position of the housing 106 relative
to the swivel bracket 16 can be adjusted. For example, the
housing 106 can be translationally or axially movable relative
to the swivel bracket 16.
The stopping means 102 also includes ~see Figs. 2-5) a
second member or switch actuator or cam member 110 mounted on
the upper end of the piston rod 44. More particularly, as
shown in Figs. 4 and S, the switch actuator 110 is a clamp-like
structure having a generally C-shaped upper portion 112 and a
--1 0--
1 334359
generally C-shaped lower portion 114. The upper portion 112
has thereon a pair of spaced apart pins 116, and has thereon a
projection 120 that is engageable with the plunger 108 so as to
move the plunger 108 to the open position. The lower portion
114 has thereon a pair of spaced apart hooks 122 which receive
the pins 116, and has therein a slot 124 through which the
piston rod 44 extends. The upper and lower portions 112 and
114 have thereon respective rearwardly extending tabs 126
secured to each other by a nut 128 and a bolt 130. When the
bolt 130 is loose, the switch actuator 110 is pivotable about
the eyelet 48, or relative to the piston rod 44 about the asis
46, so that the orientation of the switch actuator 110 relative
to the piston rod 44 is adjustable. When the bolt 130 is
tightened, the switch actuator 110 is fised in position
relative to the piston rod 44. The opposite ends of the slot
124 limit pivotal movement of the switch actuator 110 relative
to the eyelet 48.
As shown in Figs. 2 and 3, the angle of the piston rod
44 relative to the swivel bracket 16, and therefore the angle
of the switch actuator 110 relative to the swivel bracket 16,
changes as the propulsion unit 20 pivots upwardly about the
tilt axis 18. As the propulsion unit pivots upwardly, the
projection 120 eventually engages the plunger 108 and opens the
switch 104. The orientation of the switch actuator 110
relative to the piston rod 44 or eyelet 48 determines the
position or angle of the propulsion unit 20 at which the
projection 120 engages the plunger 108. In Fig. 2, the switch~
actuator 110 is shown oriented relative to the piston rod 44
--1 1--
1 334359
such that the projection 120 engages the plunger 108 when the
propulsion unit 20 has pivoted 75 from the vertical position.
In Fig. 3, the switch actuator 110 is shown oriented such that
the projection 120 engages the plunger 108 when the propulsion
unit 20 has pivoted 50 from the vertical position. Thus, the
upward tilting limit or maximum upward tilt angle of the
propulsion unit 20 can be varied by varying the orientation of
the switch actuator 110 relative to the piston rod 44.
In an alternative embodiment (not shown), the means
100 can stop upward movement of the propulsion unit 20 in
response to the position of the hydraulic assembly 34 relative
to the transom bracket 12. In this case, the means 102 would
stop upward pivotal movement of the propulsion unit 20 when the
hydraulic assembly 34 reaches a predetermined angle relative to
the transom bracket 12. More particularly, the means 102 could
include a switch mounted on the transom bracket 12 and a switch
actuator mounted on the lower end of the cylinder 36. The
switch and the switch actuator would operate in a manner
similar to the manner in which the switch 104 and the switch
actuator 110 operate.
Various features of the invention are set forth in the
following claims.
