Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02245233 1998-08-18
_ ], _
"A Rudder"
Introduction
The present invention relates to a novel construction of
rudder and to a method of using the rudder to propel a
craft.
The present invention is thus directed to rudders of the
type having a rudder blade, pivoted by a tiller and means
for securing the rudder to a boat. The rudder may be
connected to a boat by a gudgeon and pintle, it may be
connected by a stern plate with means for attaching the
stern plate to the transom or a rudder stock tube
pivotally mounted with respect to the stern plate in which
is mounted a rudder stock.
It is known to use the rudder of a boat to propel it,
This is often called sculling which is the relatively
violent movement of the tiller back and forth to cause the
rudder blade to propel the boat forward. This is
generally speaking a relatively inefficient way of trying
to propel a boat forward and is strictly prohibited for
example by the yacht racing rules. However, the general
principle of sculling, if it could be achieved efficiently
would be an extremely efficient way of propelling a boat.
One of the major problems in towing a 'boat is that
generally speaking it requires two oars unless one oar is
placed across the transom of the boat to scull it.
Another of the problems is that oars can be lost
overboard, not alone in adverse weather conditions, but
accidentally even under 'the calmest Of conditions.
Further one of the problems with oars is that very often
in narrow waterways or where there is heavy vegetation
rowing can be extremely difficult. It must also be
CA 02245233 1998-08-18
- Z -
appreciated that rowing requires some if not considerable
skill, particularly in adverse conditions. Oars are heavy
and often beyond the strength of many to use.
Further, it would be considerably advantageous that there
would always be a means other than for example oars or
sails to propel a boat.
The present invention is directed towards providing such
a means.
Statements Of Invention
According to the invention there is provided a rudder of
the type having a rudder blade pivoted by a tiller and
means for mounting the rudder on a boat, characterised in
that at least portion of the rudder blade forms a drive
fin which is connected to the tiller to allow limited
7.5 pivotal movement of the drive fin relative to the tiller.
Ideally the rudder blade is of a semi-rigid material such
as a plastics material.
In another embodiment of the invention, the rudder blade
has a rigid in-board portion fixed with respect to the
tiller forming a steering blade and an outboard portion
movable relative to the in-board portion forming the drive
fin. The advantage of this is that when the tiller is
moved back and forth, there is not just simply movement of
the tiller blade with respect to the water in the normal
way with a rigid tiller achieving a sculling motion, but
there is also the added propulsion achieved by the
flexing, as it were, of the drive fin portion of rudder
blade with respect to the tiller. This is particularly
suitable when a portion of the rudder is of a rigid
material_ At the same time, when the rudder b7_ade is of
CA 02245233 1998-08-18
- 3 -
part rigid material and of part flexible material, the
rudder will still operate effectively under normal
conditions as a rudder.
In another embodiment of the invention, the rudder blade
is a two-part rudder blade of rigid material the parts
being connected together by a friction hinge_
In another embodiment, the rudder blade is of tapered
section, having a wide front end forming the steering
blade attached to the tiller and a narrow rear end forming
a flexible drive fin. Thus advantageously, the front end
is rigid enough to form an effective steering blade while
the rear end forms the flexible drive fin for effective
propulsion when required.
In a preferred embodiment, the rudder blade comprises a
flexible drive fin having an inner end and an outer end,
the inner end being attached to a rigid plate forming the
steering blade which is attached to the tiller.
Conveniently, for size adjustment of the rudder blade,
means may be provided for adjustment of the position of
the drive fin on the rigid plate. For example, a number
of spaced-apart sets of mounting holes maybe provided in
the drive fin and the rigid plate for bolting the drive
fin in one of a number of positions on the rigid plate to
adjust the overall site of the rudder blade as zequired.
This conveniently allows a single rudder construction to
be adapted to accommodate a number of different sized
boats.
In a particularly preferred embodiment, the inner end of
the drive fin is clamped between a pair of spaced-apart
rigid plates which are attached to the tiller.
Conveniently, the pair of rigid plates may be formed from
CA 02245233 1998-08-18
- 4 -
a single sheet of metal or the like bent intermediate its
ends forming a slot for reception of the drive fin which
is secured to the rigid plates in any suitable manner_
In another embodiment, the drive fin is of plastics
material incorporating a flexible reinforcing support.
The reinforcing support may, for example, be a metal sheet
or mesh. The drive fin may be formed by moulding plastics
material about the support or the support may be
sandwiched between two panels of plastics material.
In another embodiment, a step is provided on the rudder to
aid a person entering a boat from the water.
Conveniently, the step comprises a flanged upper edge of
the rudder blade.
In another aspect of the invention there is provided an
auxiliary rudder blade of flexible material for attachment
to an existing rudder blade. There may also be simple
attachment means to allow the auxiliary rudder blade be
removably attached to an existing rudder blade. This
could allow it to be placed in position only when
propulsion is required.
While in the above the device has been described as a
rudder, as this is the device that it most clearly
resembles, it could be said that it is not strictly
speaking a rudder and that if it were of a totally
flexible material it would not be able to operate as a
rudder. However, it must still have sufficient rigidity
to allow the flexing since if it has no rigidity then it
would not act to propel a boat. Thus, it will always act
partially as a rudder, even if very inefficiently.
It is also envisaged that when, for example, an outboard
motor is mounted on the Stern of a boat across the
CA 02245233 1998-08-18
- 5 -
transom, a rudder according to the invention could be
mounted on the gunwale of the boat and used to propel the
boat. It could also be used to propel the boat, for
example, in conjunction with a conventional rudder.
This auxiliary use, for example as mentioned above with an
outboard, would be particularly suitable for angling when
drifting_
The important point to appreciate about the present
invention is that it can be used partially as a rudder, it
Can be used in conjunction with a rudder or it can be used
solely for propulsion.
Detailed Description of the Invention
The invention will be more clearly understood from the
following description of some embodiments thereof given by
way of example only with reference to the accompanying
drawings in which:-
Fig. 1 is a front elevational view of a rudder
according to the invention in the position of use;
Fig. 2 is a front elevation of a stern plate forming
part of the rudder;
Fig. 3 is a side view of the stern plate;
Fig. 4 is a perspective view of another rudder
according to the invention;
Fig. 5 is an elevational view of the ruddex of Fig.
4;
CA 02245233 1998-08-18
-s-
Fig. 6 is an end elevational view of the rudder of
Fig_ 4;
Fig_ 7 is a plan view of the rudder of Fig. 4;
Fig. 8 is a detail elevational view of portion of the
rudder of Fig. 4;
Fig. 9 is an end elevational view of the rudder
portion shown in Fig. 8;
Fig. 10 is a plan view of the rudder portion of Fig.
8:
Fig. 11 is a p~.an view of another rudder according
to the invention; and
Fig. 12 is a detail perspective view of a rudder
according to the invention incorporated iri ari
outboard motor.
Referring to the drawings and initially to Figs. 1 to 3
thereof, there is provided a rudder according to the
invention indicated generally by the reference numeral 1
comprising generally a stern plate 2 for mounting on the
transom of a boat and supporting a tiller stock tube 3 in
which is rotatably mounted a tiller stock 4 operable by a
tiller handle 5 and carrying at its lower end a rudder
blade 6.
The rudder blade 6 comprises inner rigid steel plates 10
welded to the tiller stock 4. By means of bolts 11 a
drive fin plate 12 is secured at its inner end between the
steel plates 10. The fin plate 12 has a portion of
reduced section adjacent its outer edge, provided by cut-
out portions 13 which terminate in a fish-tail 14. The
CA 02245233 1998-08-18
_ 7
fin plate 12 is manufactured from a semi-rigid plastics
material, that is a material that is stiff but flexible so
it will bend as described later.
Referring specifically to Figs. 2 and 3 the stern plate 2
is illustrated and comprises a rear plate 20 carrying a
threaded clamp 21 of conventional construction for
mounting against the transom of a boat and a front plate
22 bridged by a top plate 23 to form a substantially U-
shaped transom engaging mount. Mounted on the top plate
23 by a hinge 24 is a tiller stock support plate 25. The
front plate 22 carries a pair of spring-loaded plungers 26
engagable within sockets 27 on the tiller stock support
plate 25.
The threaded clamp 21 is used to secure the rudder 1 to
the transom of a boat. The rudder can be used as a normal
tiller_ If propulsion is required the tiller handle S is
moved relatively rapidly back and forth while gently under
normal operation such as when the boat is being driven by
a motor or by sails, the rudder 1 will operate in
conventional manner.
However as mentioned above, when it is desired to propel
the boat, the handle 5 can be moved back and forth
relatively vigorously and this will cause a relative
pivotal movement within the rudder blade 6 in that the fin
plate 12 will bend back and forth or pivot relative to the
inner portion formed by the rigid steel plates 10 and thus
provide a propelling movement somewhat similar to sculling
or indeed the action of a fish's tail. It will be
appreciated that the construction of rudder blade 6 is.
such that its action will mixror that of a .fish's tail.
In operation it will be appreciated that by disengagement
of the spring-loaded plungers 26 that the tiller stock
CA 02245233 1998-08-18
- 8 -
support plate 25 can be hinged upwardly and hence the
rudder blade can be pivoted out of the water.
Referring now to Figs. 4 to 10, there is illustrated
another rudder 40 according to a second embodiment of the
invention. The rudder 40 comprises a rudder blade 41
mounted on a tiller stock 42 which is pivoted by a tiller
43. The tiller stock 42 is rotatably mounted in a pair of
bushings 44 or bearings carried on a mounting plate 4S
which is engagable with a transom on a boat to mount the
rudder 40 on the boat.
The rudder 40 is of two-part construction comprising a
flexible drive fin 47 having an inner end 48 and an outer
end 49. The inner end 48 is clamped between a pair of
rigid metal plates 50 formed from a single piece of metal
bent intermediate its ends into a U-shape. An inner end
51 of the metal plate 50 is welded to the tiller stock 42.
Mounting belts 53 pass through the metal plate 50 and the
inner end 48 of the drive fin 47 to secure the drive fin
47 between the metal plates 50. A free outer end of the
drive fin 47 has a fish tail configuration 55 as
previously described. The flexible drive tin 47 is of
plastics material and incorporates a flexible metal
reinforcing support plate 57 shown in broken outline in
Fig. 5.
The tiller 43 has a cranked arm 60 with a handgrip 61 at
an inner end of the arm 60. An outer end 62 of the arm 60
is mounted within an associated collar 64 at a top of the
tiller stock 42. A locking pin 65 retains the arm 60 in
engagement with the collar 64. A chain 67 1s mounted
between the arm 60 and the collar 64 and serves to retain
both the arm 60 and the pin 65 when they are removed from
the collar 64. It will be noted that as the tiller arm 60
is cranked, it can be mounted in a number of positions as
CA 02245233 1998-08-18
_ g -
shown in Fig. 7, either extending to the left as shown iri
Fig. 7 or to the centre or right as shown in broken
outline in Fig. 7_
It will be noted that a step 69 is provided at an upper
edge of the plates 50 to assist in getting into a boat
from the water.
Referring now to Figs. 8 to 10, there is shown another
rudder 70. Parts similar to those described previously
are assigned the same reference numerals. In this case,
the drive fin 47 has two spaced-apart rows of mounting
holes 71, 72 for engagement with the mounting bolts 53
which pass through both the steel plates 50 and the drive
fin 47. This allows for adjustment of the length of the
drive fin 47 to accommodate different Sized boats.
Referring now to Fig. 11, there is shown another rudder
B0. In this case, the rudder 80 is of plastics
construction and is of tapered section having a wide front
end 81 attached to the tiller stock 42 and forming a stiff
steering blade and a narrow rear end 92 forming a flexible
drive fin
Referring to Fig. 12, there is shown another rudder 90.
Parts similar to those described previously are assigned
the same reference numerals. In this case, the rudder 90
is attached to an outboard motor of which, in the drawing,
only a drive shaft assembly bottom portion 91 with
propeller 92 is shown. A pair of mounting brackets,
namely an upper mounting bracket 93 and a lower mounting
bracket 94 are attached to an inner end 51 of the metal
plate 50. These mounting brackets 93, 94 extend forward
and are secured by mounting bolts 95 on the drive shaft
assembly bottom portion 91.
CA 02245233 1998-08-18
- 10 -
In use, the outboard motor can be operated in usual
fashion to propel a boat, the rudder 90 aiding steering of
the boat. In effect, the outboard motor forms a tiller
stock and tiller for the rudder 90- This arrangement is
particularly advantageous for anglers. Usually, if one is
drifting a boat during fishing, one must use oars as the
motor would be too noisy. However, even oars are
relatively noisy whereas the rudder 90 can be used to
control the boat in a quiet efficient manner. Also, in
the event of engine breakdown, the rudder 90 can be used
to propel the boat.
Tests to date have shown that the rudder of the invention
requires less physical effort foX propuls.i_on than with the
use of oars. It has the additional advantage that the
present invention can be operated with one hand and the
user has the freedom to use the other hand for other tasks
such as, for example, fishing, picking up moorings and the
like maritime tasks.
An additional advantage of the present invention is that
it can be used by either right or left handed users.
A particular advantage of the present invention is that in
adverse weather conditions or, for example, in relatively
strong current it ensures constant thrust with less
physical effort as compared with rowing a boat in that
when oars are removed from the water in the return stroke
the boat is depending on the imparted motion already
provided to the boat to keep it moving.
Another particular advantage of the present invention is
that it will be relatively difficult, if not impossible,
to lose the rudder overboard since it will at all times be
securely clamped in position.
CA 02245233 1998-08-18
- 11 -
A further advantage of the present invention is that it
requires no operator skill while rowing and particularly
sculling with a single oar is a very skilful task and
becomes particularly so in adverse weather conditions such
as heavy chop or high winds.
A further advantage of the present invention is that in
areas where there is heavy vegetation or the waterway is
particularly narrow 'the invention will continue to operate
where conventional oars would be very difficult if not
impossible to use,
A further advantage of the present invention is that since
it combines the functions of both propulsion and steering,
there is now the need to carry only one piece of equipment
or to fix one piece of equipment to the boat.
It will be appreciated That while the invention described
above has been described with reference to a removable
rudder or tiller assembly for mounting on the transom of
a boat that the invention can be readily easily applied to
other constructions of tiller or rudder or may simply be
a removable add-on device ~or existing rudders.
The invention is not limited to the embodiments
hereinbefore described which may be varied in both
construction and detail.
