Outboard motor bracket assembly

A trimming, tilting and transom bracket assembly for a drive leg for a boat including a single tilt pin supportingly carried by a transom bracket, a swivel bracket tiltably carried by the tilt pin steerably supporting the leg, a member carried by the pin interposed between the transom bracket and the swivel bracket, and trim adjusting elements between the transom bracket and such element and trim adjusting elements between such element and the swivel bracket.

The invention relates to an outboard motor bracket assembly of the type 
wherein a motor, which is provided with a drive leg, is steerably, 
trimably and tiltably attached to the transom of a boat, a first motor 
bracket part being swingable about an essentially horizonal axis attached 
to the said transom, and the motor itself being rotatably attached to a 
second motor bracket part displaceable about an essentially horizontal 
axis relative to such first part and co-operating therewith. Trimming is 
used herein to refer to the relatively small and tilting to refer to the 
larger swinging movement of the outboard motor around a tilt axis to 
adjust the motor, and accordingly the propeller, in an optimum driving 
trim position, or for tilting the motor into a rest position in which, 
typically, the propeller is entirely out of the water. 
The trimming and the tilting may be accomplished manually, but it is also 
contemplated that a cylinder-piston unit may be arranged between the 
upright steering axis, the axis around which the motor is swung 
horizontally or laterally for the steering of the boat, and the boat 
transom, or an attachment attached to the transom, such cylinder-piston 
unit being driven by a pressurized fluid supplied from a pump provided 
with a reservoir and located on the bracket assembly or inside the boat, 
whereby the trimming and the tilting may be remotely controlled, for 
instance from a driver's station located forwardly in the boat. 
An object of the present invention is to provide an improved bracket 
assembly of the type above mentioned especially wiith a view to an 
improvement of the trimming action and improved ease of operation. 
According to the invention, not only are the trimming and tilting 
operations entirely separate, since the tilting takes place merely between 
the first and the second part of the bracket assembly, but there also 
exist two separate trimming possibilities, that is between the boat 
transom and the first part and between this first part and the second 
part, such trimming possibilities being in addition to the tilting 
possibility. 
The first part as well as the second part are swingable around a 
substantially horizontal axis which may be embodied in a separate tilt pin 
for each of the two parts, or the axes may be coincident and, in this 
case, each part may be mounted on and swing vertically about the axis of a 
single tilt pin. The single tilt pin arrangement is to be preferred, 
wherein the single tilt pin is mounted to the transom bracket, and thus to 
the boat. The bracket fixed to the transom includes an elongated bearing 
yoke, extending substantially horizontally, in the legs of the yoke the 
tilt pin is mounted, while between the yoke legs, the first part is 
mounted, and outside the legs, the second part is mounted on the tilt pin. 
Preferably, the tilt pin is mounted slightly forwardly of the transom, 
which brings about certain advantages, particularly in that the 
inclination of the motor, thus achieved is such that the drive shaft of 
the motor, as well as the steering axis, are rearwardly inclined in the 
downward direction. Compared with the conventional arrangement, where the 
axis of the tilt pin intersects the steering axis, the angle through which 
the motor has to be tilted upwardly so that the lowermost portion of the 
leg will be lifted to the level of the bottom of the boat, will be smaller 
due to the altered geometrical conditions. Furthermore, as a result of the 
favorable mutual position of the tilt pin relative to the center of 
gravity of the motor, a smaller force is required to tilt the motor 
upwards a certain number of degrees, and the greater the forward 
displacement of the tilt axis with respect to the steering axis, the more 
noticeable this advantage becomes. 
Furthermore and preferably, the tilt pin may be so designed as to be able 
to accommodate the end portion of a known co-axial cable-control device. 
Specifically, the tilt pin is preferably made as a tube, in the interior 
of which the end portion of the steering cable casing may be fixed. The 
active core of the control device which terminates in a rod movable with 
the core, is attached via a shaft to an arm portion of the motor. 
The device according to the invention is particularly adapted to be 
supplemented by a simple novel tilt or reverse lock which will be 
described further in connection with the embodiment disclosed. 
The device according to the invention is especially well suited for being 
complemented by at least one extensible expansible chamber device, such as 
a cylinder-piston assembly, between the boat transom and the first 
tiltable motor bracket part, and/or between such first part and the second 
tiltable motor bracket part. 
Such expansible chamber device, or cylinder piston assembly or assemblies 
may be arranged for serving different purposes, and in the first place for 
the remote control of the trimming and tilting of the motor from the 
driver's station. It is furthermore contemplated that a cylinder-piston 
assembly disposed between the first bracket part and the second bracket 
part may be designed as a gas-filled shock absorber to cushion the return 
of a motor which has been tilted, such as by striking an underwater 
object, to its normal upright drive position. The cylinder may, for 
example, be filled with a fixed amount of gas, or connected to an 
accumulator which, with the cylinder, contains such fixed amount of gas, 
such that the cylinder balances all or some of the weight, or downward 
gravitational force, of the motor when in its tilted position. The device 
according to the invention allows to a large extent the use of pressmolded 
details which do not require subsequent working or finishing, whereby the 
production costs are minimized.

According to FIG 1, an outboard motor 10 comprises a motor housing or 
shroud 11, under which the motor 12 itself is accommodated, and a leg 
housing 13, in which the output drive shaft, symbolically indicated by its 
axis MA, of the motor 12 extends, which in the propeller gear housing 17a 
transfers its rotation to the propeller shaft represented by its axis PA, 
on which the propeller 17 is attached. On the external side of the leg 
there is arranged an anti-cavitation plate 10. The motor is provided with 
an outwardly and forwardly extending steering arm 11b which carries an 
outer end ball attachment 11a for attaching the inner operating part or 
core 11e of a coaxial remote control single, push-pull steering cable 11f. 
The motor 12 carries, preferably under shroud 11, a servo-motor 12a, the 
purpose of which will be explained later. 
A bearing yoke 40 is screwed onto the transom 20 of a boat by means of a 
screw bolt 41. The two legs 40a, 40b (FIG. 2) of the bearing yoke 40 carry 
a tilt pin 42 which extends, preferably rotatably therethrough. The tilt 
pin is symbolically indicated in FIG. 2 by its axis TA. Preferably this 
tilt pin is in the form of a tube, so that in the interior thereof the end 
portion of the casing of a single-cable control device may be attached. 
The control element or core, which may terminate in a projecting rod, is 
linked by known means to the ball attachment 11a of the motor 10. 
On the tilt pin 41 two construction elements are swingable journalled: on 
the middle portion thereof, i.e. between the legs 40a, 40b a first part 50 
is carried while on the outer end portions, i.e. on the outer sides of the 
legs 40a, 40b, a second part 60 is mounted. The second part 60 comprises, 
as shown, a yoke-shaped support element 61 of which the legs, which are 
engaged on the pin 42, are disposed outwardly of the legs 40a and 40b, 
respectively. The second part 60 suppports the steering shaft of the 
motor, which in FIG. 1 is indicated symbolically by its axis SA. 
Preferably, the second part 60 is made of two symmetrical halves, which 
are mounted together by means of attachment bolts, such as bolts 60x, 60y 
and 60z. 
The first part 50 is at its lower end 50a adjustably connected to the 
transom 20 by means of a pin 51 selectively positioned in one or another 
of the holes 21f in an arm 21e which protrudes from a transom plate member 
21. In this manner one trimming possibility is obtained. The second part 
60 is also provided with a row of several holes 60f. A pin 61 is 
positioned in a selected hole 60f, the pin being located in the middle 
hole in FIGS. 1 and 3. A second trimming possibility is obtained by this 
arrangement. To prevent tilting-up of the motor when driving in reverse, 
and at the same time to afford such tilting-up when an underwater obstacle 
is hit during forward driving, as well as when desired when the boat is 
standing still, a tilt for reverse lock 70 is arranged on the first part 
50 for locking the part 60 thereto. As seen in FIG. 3, the reverse lock 70 
comprises essentially a straight link 75 and an S-shaped hook member 71, 
which at its forward bent portion curves under and engages upwardly a pin 
76 which passes through a hole in the link 75 and in the yoke member or 
first part 50. The hook 71 has a rearward downwardly inclined bend portion 
which extends, when the leg is in operating position, above and engages 
downwardly on a pin 61 which is positioned in a desired one of holes 60f, 
and which such pin is thus rigidly connected to the second part 60. In the 
internal space 50b of the first part 50 tension spring 72 is disposed with 
its upper end anchored to the part 50, and with its lower end attached to 
the hook 71 at a place 71b at the terminal portion of the upwardly bent 
front portion thereof, forwardly of the pin 76. An elongated pulling 
element or link 73 is connected to the hook member 71 rearwardly of the 
pin 76 about which the hook member is rockable, and, preferably, at a 
point generally aligned above the area of contact of the hook with pin 61, 
such as by means of the attachment pin 71a. The link 73 extends upwardly 
within the interior space 60b of the second part 60 to an attachment 73a 
at its upper end to the rearward end portion of an operating lever member 
74. Lever member 74 is pivotally mounted between its ends on a pin 74a to 
the first part 50 and terminates forwardly in a manually engageable button 
or tab portion 74b, such that depression of tab 74b causes the lever 74 to 
rock on pivot pin 74a in a direction to raise link 73 and thus to raise 
the rearward hook end of hook member 71 free of pin 61 against the bias of 
spring 72, thereby to free the second part 60 for upward and rearward 
tilting of the motor. When the motor strikes an underwater object, the 
force of the pin 61 against the inner inclined surface of the hook at its 
engagement with the pin by cam action overcomes the biasing force of 
spring 72 causing the hook member 71 to rock about pin 76 into a position 
to free the lock pin 61 and thus to permit upward swinging of the motor. 
The upper portion of the transom bracket 21 is provided with a round hole 
21m for the transom attachment bolt 41 and at its lower end it is provided 
with a guide tongue portion 21n. By letting the screw bolt 41 pass through 
the transom 20 in an upwardly and downwardly oriented elongated transom 
slot 20k, which slot is located above the water line, the entire bracket 
assembly may be mounted height-adjustably. The guide tongue portion 21n is 
transversely caged between two guide elements 20n bolted to the transom. 
It will be appreciated that the side forces, which act on the second part 
60 when steering to the side, are effectively transferred to the transom 
20 in that the side wings 60a of the second part 60 abut against 
corresponding side surfaces on the first part 50, and the bifurcated lower 
part 50a of this first part 50 itself abuts against the arm 21e of the 
transom bracket 21, whereafter the side forces are taken up the guiding or 
caging elements 20n which are bolted to the transom 20. Simultaneously, 
the side wings 60a provide a favorable lateral fixation of possible 
cylinder-piston assembly 65 (FIG. 5) mounted between the first and the 
second parts. 
In the embodiment according to FIG. 4, the arm 21e and the row of holes 21f 
have been replaced by a first cylinder-piston assembly 55 extending 
between the transom 20 and the transom bracket plate 21, on the one hand, 
and the lower portion 50a of the first part 50, on the other hand. By 
remote control of this assembly, for instance from a forwardly located 
driver's station it is possible while the boat is being driven to adjust 
the trim to provide the correct propeller position for the particular 
speed loading and other conditions. The basic trimming, i.e. the adaption 
to different boat types having differently inclined transoms, is carried 
out when first mounting the motor on the particular boat by means of the 
row of holes 60f and of the pin 61. The pin 61, in the arrangement as 
shown in FIG. 4, has been selectively placed in the forwardmost hole. With 
a more inclined transom, it might be placed in the second hole 60f, for 
example. 
For tilting up, there is connected between the first part 50 and the second 
part 60, and disposed in the interior spaces 50b, 60b thereof (FIG. 3), a 
second cylinder-piston assembly 65. This assembly, by means of a pin 65a, 
is swingably attached to the second part 60, and this assembly can also be 
remotely controlled from the driver's station. The cylinder-piston 
assemblies 55, 65 are supplied from a source of pressurized fluid which 
may be arranged either in the boat or, as taught in my copending 
application Ser. No. 827,004 filed concurrently herewith, now U.S. Pat. 
No. 4,119,054, under the motor housing 12. For the sake of clearness, 
neither said source nor the conduits belonging thereto are shown. The side 
surfaces 55a of the piston in the assembly 55 preferably bow outwardly, 
that is, the piston may be an O-ring piston, so that the piston rod 55b 
may perform the necessary smaller angular movements. Alternatively, this 
piston rod may be attached to the portion 50a by means of an elongated 
slot, or the assembly may be replaced by a rubber bellows. 
Instead of a single cylinder-piston assembly 65, two adjacent parallely 
connected cylinder-piston units in a double assembly may be preferred, 
especially in connection with heavier motors. 
In a manner known per se, this second cylinder-piston assembly 65 also can 
be arranged for performing the function of a hydraulic reverse lock, by 
providing valves to close off the hydraulic connections to the cylinder. 
It will be understood that the cylinder-piston assemblies also may be used 
in one place only i.e. between the transom bracket and the first part, or 
between the first part and the second part, while the setting at the other 
place is then carried out mechanically in a manner according to FIG. 1. 
It is known to design cylinder-piston assemblies in an outboard motor as 
shock absorbers and to fill the cylinder or cylinders with a gas, the 
pressure of which, acting on the piston completely or partially balances 
out the weight of the motor when the motor is tilted upwards. According to 
the present invention, the cylinder-piston assembly or assemblies between 
the first part and the second part may be arranged similarly, i.e. for 
performing also a shock-absorption function, in addition to their lifting 
function. 
In the embodiment according to FIGS. 1 and 3, the steering shaft with the 
axis SA may be undivided, i.e. an integral unit from the upper to the 
lower end. When the second cylinder-piston assembly 65 is used, the 
steering shaft is, however, divided according to FIG. 5 preferably into an 
upper pivot pin 66a journalled in an upper pivot bearing 68a and a lower 
pivot pin 66b journalled in a lower pivot bearing 68b. In this way, enough 
space is obtained in the interior space 60b of the second part 60 for the 
attachment of the assembly 65, partly, also, thanks to the above described 
back rearward inclination of the steering axis. In a manner known per se, 
the pivot pins 66a, 66b are at 67a, 67b resiliently mounted in the leg 13 
to achieve vibration absorption. 
Basically, the pivot bearings for the upper and lower portions of the 
steering shaft may be mounted alternatively in the second part 60, rather 
than to the motor 10 and the leg 13 as shown. The last mentioned 
situation, as illustrated in the drawings brings about however, a number 
of advantages. 
The second part 60, as shown in FIGS. 4 and 5, includes two symmetrical 
halves which are screwed together by bolts such as 60x, 60y, 60z. By this 
bolted connection also pivot pins 66a, 66b are fixed in position in the 
two halves, in that the bolts 60y and 60z pass through notches 
interrupting the cylinder surfaces of the pivot pins, so that the pivot 
pins are locked against rotation in the second part 60. The pivot bearings 
68a, 68b are embedded in rubber blocks 67a, 67b for vibration-absorption, 
as mentioned above. This arrangement has the additional advantage that the 
two pivot pins 66a, 66b need not be especially well aligned, since small 
deviations are compensated by the rubber blocks. The construction shown 
has further the spare spaces 67c, 67d which make it possible that a 
varying number of rubber blocks may be mounted on the pivot pins (for 
instance a greater number with slower boats and motors, and a smaller 
number with faster motors). 
In order to enable compensation for different heights of transoms of 
different boat types, it is known to provide outboard motors with a so 
called extended or long leg. FIGS. 5 and 6 disclose that the same effect 
easily may be obtained with the assembly according to the present 
invention in that spacing members, for instance washers 66c, may be 
slipped onto the upper and/or lower pivot pin, for instance in the manner 
schematically shown in FIG. 6 for the lower pivot pin. When such spacing 
washers are slipped over the lower pin, the leg will be lowered with 
respect to second part 60, thus to compensate for a taller transom, that 
is to say, a transom which carried the tilt pin 42 higher with respect to 
the water level, while, if fewer spacing washers are positioned on the 
lower pivot pin and more such washers are so positioned on the upper pin, 
the leg will be effectively shortened to adapt the motor and its mounting 
to a lower transom height. It will be appreciated that an analogous 
construction, for the same purposes also may be used when the pivot 
bearings are mounted in the second part. Necessary for this adjustment 
facility is that the distance between the two shoulders on the motor, 
between which the second part is inserted, is made longer than the length 
of the second part. This adjustment facility is of course a replacement 
for, and/or a supplement to, the facility obtained by the elongated slot 
20 k (FIG. 3) when the steering shaft is undivided. Regardless however, in 
which way the spacing washers are distributed between the upper and lower 
pivot pins, the increased mutual spacing between the rubber blocks 67a and 
67b brings about the advantage of an increase vibration attentuating 
effect. 
In FIG. 5 two alternative steering possibilities of the motor 10 are shown. 
On the one hand, it is the already described outer steering possibility, 
where a not shown rod of a push-pull sngle cable control system is 
attached to the ball attachment 11a on an outer steering arm 11b. On the 
other hand there is provided in addition an inner steering arm 11c under 
the motor housing or shroud 11, and the arm 11c carried an inner ball 
attachment 11d, the arm 11c being rigidly attached to the upper pivot pin 
66a. A remotely operated control member, for instance an electrical 
servo-motor 12a, is fixedly attached to the motor 12 (FIG. 1) or to an 
element rigidly connected thereto. The control member drives an operating 
rod 12b, the one end of which is connected to the inner ball attachment 
11d. 
In that the arm 11c is rigidly attached to pivot pin 66a, and the pivot pin 
is fixed by bolt 60z against rotation with respect to the bracket 
assembly, and is thus non-rotatable on its axis with respect to the boat, 
the arm 11c does not swing in a steering direction about axis SA. 
By displacing the operating rod 12b with the arm of the servo-motor 12a in 
a desired extent in a lateral direction perpendicular to the plane of the 
drawing, an inside power steering is obtained controllable by remote 
electrical or hydraulic controls for the servo-motor. 
While in FIG. 4 the motor 10 is shown in its extreme outward trim position, 
where the piston of the first cylinder-piston assembly 55 is maximally 
extended and the pin 61 is located in the forward one of the hole 60f, in 
FIG. 5 the motor is shown in a medium trim position where said piston has 
movement possibilities in both directions and the pin 61 is placed in the 
middle one of the holes 60f. 
It will be appreciated that according to the present invention the basic or 
rough trimming that, the adaptation to different transom inclinations, may 
be carried out either between the transom bracket and the first part, as 
is specifically contemplated in the embodiment according to FIGS. 1 and 3, 
or between the first and the second parts, as is specifically contemplated 
in the embodiment according to FIGS. 4 and 5, while the fine trimming is, 
of course, executed between the other pair of said elements. 
To a great extent, the device according to the invention allows the use of 
precision molded construction elements which require no subsequent 
machining or finishing whereby the production costs are minimized. 
While the invention has been described with respect to certain specific 
embodiments, it will be appreciated that many modifications and changes 
may be made by those skilled in the art, without departing from the spirit 
of the invention. It is intended, therefore, by the appended claims to 
cover all such modifications and changes as fall within the spirit and 
scope of the invention.