U.S. patent application number 10/248738 was filed with the patent office on 2004-08-19 for watertight flywheel housing for boats using a stern drive system.
Invention is credited to Neisen, Gerald F..
Application Number | 20040161983 10/248738 |
Document ID | / |
Family ID | 32849387 |
Filed Date | 2004-08-19 |
United States Patent
Application |
20040161983 |
Kind Code |
A1 |
Neisen, Gerald F. |
August 19, 2004 |
WATERTIGHT FLYWHEEL HOUSING FOR BOATS USING A STERN DRIVE
SYSTEM
Abstract
The present invention provides a stern drive propulsion system
that includes an internal combustion engine having a flywheel and a
watertight housing that sealingly encloses the flywheel relative to
the surrounding environment. The housing may support a starter
coupled to the flywheel and extending toward the transom of a boat.
A starter seal is provided to seal corresponding interface surfaces
of the starter and the flywheel housing.
Inventors: |
Neisen, Gerald F.; (Oshkosh,
WI) |
Correspondence
Address: |
BOMBARDIER RECREATIONAL PRODUCTS
LEGAL SERVICES - ST. BRUNO
PO BOX 230
NORTON
VT
05907-0230
US
|
Family ID: |
32849387 |
Appl. No.: |
10/248738 |
Filed: |
February 13, 2003 |
Current U.S.
Class: |
440/76 |
Current CPC
Class: |
B63H 20/32 20130101;
F02B 61/045 20130101; F02F 7/0073 20130101; F02B 75/06
20130101 |
Class at
Publication: |
440/076 |
International
Class: |
B63H 020/32 |
Claims
What is claimed is:
1. A sealed starter and flywheel arrangement for a marine
propulsion system, the arrangement comprising: a flywheel housing
coupled to an engine block; a flywheel sealingly disposed within
the housing; a starter supported by the flywheel housing; and a
starter seal sealing the starter to the flywheel housing.
2. The arrangement of claim 1 wherein the starter is coupled to the
flywheel and the flywheel housing such that water is prevented from
entering the starter.
3. The arrangement of claim 1 wherein the starter seal includes at
least one of an o-ring and a gasket.
4. The arrangement of claim 1 wherein the starter has a proximate
end supported by the flywheel housing and a distal end facing a
transom of a watercraft.
5. The arrangement of claim 4 wherein the flywheel housing is
interposed between the engine block and a transmission housing.
6. The arrangement of claim 5 wherein the flywheel housing further
comprises a bottom plate sealingly closing a bottom section thereof
and the engine block.
7. The arrangement of claim 1 wherein the flywheel housing provides
a watertight enclosure for the flywheel.
8. A stern drive propulsion system comprising: a watertight
enclosure having a flywheel disposed therein; a starter supported
by the enclosure and coupled to the flywheel such that the starter
is positioned between an engine block and a rear transom of a
marine watercraft; and a starter seal configured to seal
corresponding interface surfaces of the starter and the
enclosure.
9. The propulsion system of claim 8 wherein the watertight
enclosure includes a flywheel housing and wherein an upper section
of the flywheel housing supports the starter.
10. The propulsion system of claim 8 wherein the watertight
enclosure is interconnected between the engine block and a
transmission housing.
11. The propulsion system of claim 11 wherein the watertight
enclosure further includes a bottom plate sealingly closing a
bottom section thereof and the engine block.
12. A kit for a stern drive propulsion system including an internal
combustion engine having a flywheel, the kit comprising: a housing
configured to provide a watertight enclosure for a flywheel; a
starter connectable to the flywheel; and a starter seal for sealing
the starter to the housing.
13. The kit of claim 12 wherein the housing is configured to be
interconnected between an engine block and a transmission
housing.
14. The kit of claim 12 wherein the starter seal includes at least
one of a gasket and an o-ring.
15. The kit of claim 12 wherein the starter is supportable in an
upper section of the housing.
16. The kit of claim 12 wherein the starter has a proximate end
supported by the housing and a distal end facing a transom of a
boat.
17. The kit of claim 12 wherein the housing further comprises a
bottom plate sealing a bottom interface of the housing and an
engine block.
18. A stern drive propulsion system comprising: means for sealingly
attaching a flywheel housing to an engine block such that elements
from an outside environment are resistant from entering the
flywheel housing; means for supporting a starter provided by the
flywheel housing; means for sealingly coupling a starter to the
flywheel housing such that the components within the starter are
protected from external debris.
Description
BACKGROUND OF INVENTION
[0001] The present invention generally relates to a structural
arrangement for preventing water entry in a boat propulsion system
and, more particularly, to an improved arrangement for preventing
the entry of water into the flywheel housing of a stern drive.
[0002] FIG. 1 shows one example of a commonly used marine
propulsion system having a stern drive 2, in which an internal
combustion engine 4 is mounted within the hull 6 of a boat 8 and to
a propulsion unit 10 that is mounted outside of hull 6. The engine
4 drives the stern drive 2 by an output shaft (not shown) that
extends through transom 14 of boat 8. One common practice is to
provide some form of elastic coupling between the output shaft of
engine 4 and an input shaft of propulsion unit 10 so as to
accommodate angular misalignments. The elastic coupling permits
movement of engine 4 so as to absorb vibrations by its resilient
support. These flexible couplings are normally positioned in
proximity to a flywheel 16 of engine 4 to provide damping at the
desired location.
[0003] Although this type of arrangement is generally satisfactory,
it has been a common practice to provide a flywheel housing 18 or
cover that encircles the flywheel 16 but which, as shown in FIG. 2,
has a relatively large opening 32 that is positioned in proximity
to the flexible coupling 1 3 and normally encircles it.
Unfortunately, because. of the presence of such an opening in the
flywheel housing 18, there is a high probability that water may
enter into the interior of the flywheel housing 18. The large
diameter of opening 32 places the lower peripheral edge quite low
in the watercraft and hence it is prone to the likelihood of bilge
water entering therethrough. When water enters flywheel housing 18,
rotation of flywheel 16 throws the water in contact with starter 35
of engine 4. The water can readily cause corrosion of the starter
and/or electrical shorts which can render its operation either
difficult or, in some instances, inoperative.
[0004] Known systems purport to alleviate and/or prevent the entry
of water. These systems implement a "water slinger" to discharge
water entering the interior of the flywheel housing, best shown
FIG. 2. That is, flywheel housing 18 is formed with a water
discharge opening 37 that is disposed slightly above the lower end
of flywheel housing 18 and in the direction of rotation of flywheel
16. The water discharge opening 37 is also located below, or
before, the location of starter 35. A protruding lip 38 overlies
the discharge opening 37 so that any water which may enter flywheel
housing 18 should, in theory, be thrown upwardly due to deflection
caused by lip 38 and enter the discharge opening 37. A conduit 39
extends from the discharge opening 37 to a discharge point 41 above
the highest level of anticipated water in the hull to discharge
water from the flywheel housing.
[0005] Unfortunately, in practice, although lip 38 may deflect some
water into discharge opening 37, it will be appreciated that in the
presence of a large volume of water inside of flywheel housing 18,
some water will also be thrown in the direction of starter 35 and
thus the starter is still subject to the above difficulties.
Further, water may enter flywheel housing 18 through discharge
opening 37 or may not be forced up conduit 39 with sufficient force
to be completely discharged.
[0006] It would thus be desirable to provide an improved driving
arrangement for a stern drive that will preclude the entry of water
into the flywheel housing. It would be further desirable to provide
a drive arrangement for a stern drive that provides a sealed
flywheel housing relative to its surrounding environment to
effectively insure against the entry of water into the flywheel
housing.
BRIEF DESCRIPTION OF INVENTION
[0007] The present invention fulfills the foregoing needs by
providing a stern drive propulsion system for a watercraft. The
system comprises an internal combustion engine having a flywheel
and a watertight housing sealingly enclosing the flywheel relative
to the surrounding environment.
[0008] Therefore, in accordance with one aspect of the present
invention, a sealed starter and flywheel arrangement for a marine
propulsion system is provided. The arrangement includes a flywheel
housing coupled to an engine block as well as a flywheel sealingly
disposed within the housing. The arrangement further includes a
starter supported by the flywheel housing and a starter seal
sealing the starter to the flywheel housing.
[0009] In accordance with another aspect of the present invention,
a stern drive propulsion.system includes a watertight enclosure
having a flywheel disposed therein and a starter supported by the
enclosure and coupled to the flywheel. The starter is supported by
the enclosure and coupled to the flywheel such that the starter is
positioned between an engine block and a rear transom of a marine
watercraft. The system further includes a starter seal configured
to seal corresponding interface surfaces of the starter and the
enclosure.
[0010] According to yet another aspect of the present invention, a
kit for a stern drive propulsion system including an internal
combustion engine having a flywheel is provided. The kit includes a
housing configured to provide a watertight enclosure for a flywheel
as well as a starter connectable to the flywheel. The kit also
includes a starter seal for sealing the starter to the housing.
[0011] In accordance with yet another aspect of the present
invention, the stern drive propulsion system, includes means for
sealingly attaching a flywheel housing to an engine block such that
elements from an outside environment are resistant from entering
the flywheel housing. Means for supporting the starter provided by
the flywheel housing as well as means for sealingly coupling the
starter to the flywheel housing such that the components within the
starter are protected from exterior debris is also provided.
[0012] Various other features, objects and advantages of the
present invention will be made apparent from the following detailed
description and the drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0013] The drawings illustrate one embodiment presently
contemplated for carrying out the invention.
[0014] In the drawings:
[0015] FIG. 1 is a side elevational view of a prior art stern drive
marine propulsion system mounted in a boat shown in partial
cross-section.
[0016] FIG. 2 is a rear elevational view of the flywheel enclosure
of the stern drive of FIG. 1.
[0017] FIG. 3 is a side view of a stern drive, in partial
cross-section, incorporating the watertight flywheel housing in
accordance with one aspect of the present invention.
[0018] FIG. 4 is a perspective view of the flywheel housing of FIG.
3 partially sectioned to view the flywheel.
[0019] FIG. 5 is a partial elevational view of a bottom section of
the flywheel housing of FIG. 3.
DETAILED DESCRIPTION
[0020] FIG. 3 shows an exemplary marine propulsion system 100
having an internal combustion engine 102 located within a
watercraft, such as a boat 103, having a transom 104 at a rearward
end thereof. Standard engine mounts 106 attach engine 102 to boat
103. The engine 102 provides power to a drive shaft 108 that
extends through the transom 104 of the boat. A gimbal housing 110
is mounted to transom 104. In one exemplary embodiment, gimbal
housing 110 forms a part of the housing for a multiautomatic
transmission 112 in a transmission housing 113. By incorporating a
multitransmission with reverse gearing into the gimbal housing 110,
the propulsion system is adapted to be used in place of a standard
single speed inboard/outboard marine propulsion system. Two sets of
planetary gears having a common ring gear may be used to provide a
very compact two transmission with reverse gearing capability, thus
permitting such a transmission to be packaged within the space
provided by the gimbal housing of an inboard/outboard marine
propulsion unit. It will be appreciated that for purposes of the
present invention, the operation of the transmission need not be
described in any greater detail.
[0021] As will be readily understood by those skilled in the art,
the gimbal housing supports a gimbal unit 114, which includes a
pivot housing 116 and a gimbal ring 118. Gimbal unit 114 is
horizontally pivotable to provide steering to the boat in a desired
direction of travel and is further vertically pivotable to provide,
for example, a desired trim relative to the water plane over which
the boat travels. Gimbal unit 114 accommodates a universal joint
119 therein comprising at one end thereof an input shaft, e.g.,
driveshaft 108, and having at an opposite end an output shaft 121
connectable to a propulsion unit 124, generally referred to in the
art as vertical drive unit or outdrive, for allowing vertical and
horizontal pivoting. Standard gears and driveshafts within outdrive
124 cooperate to transmit power from the output shaft 121 to a
propeller shaft located in a lower gear case 123 appended at the
lower end of drive unit 124 to drive propeller 125.
[0022] As shown in greater detail in FIG. 4, a flywheel housing 200
sealingly encloses flywheel 16 of the engine relative to the
surrounding environment. Flywheel housing 200 supports a starter
202 coupled to flywheel 16. Flywheel housing 200 is interposed
between engine block 102 and transmission housing 113. Flywheel
housing 200 is a watertight housing and is free from any opening to
the operating environment. It will be appreciated that this aspect
of the invention prevents the entry of any water into the interior
of the flywheel housing and thus avoids having to rely on any
"water slinger" structure or water diverter such as that described
with reference to FIG. 2.
[0023] An upper section of flywheel housing 200 supports starter
202. This arrangement avoids exposure of the interior of starter
202 to water that may leak into the bilge of the watercraft. To
further ensure that the interior of the starter remains free from
moisture, a starter seal 210 is provided to seal the corresponding
interface surfaces of starter 202 and flywheel housing 200. Starter
seal 210 may be a gasket or sealing ring. This arrangement prevents
water entry through the interface and into the starter gear drive
and starter engagement mechanism. It will be appreciated that the
interior of the starter is thereby sealed relative to the
surrounding environment.
[0024] Starter 202 has a proximate end 204 supported by the
flywheel housing and a distal end 206 generally facing the transom
of the boat. This arrangement adds to the ease of accessibility of
the starter as opposed to the arrangement shown in FIG. 1. The
prior art arrangement has the starter positioned axially inward
relative to the transom of the boat. Removal of the starter shown
in FIG. 1 may require time consuming and costly removal of the
stringers of the boat to clear the engine block or disconnecting
motor mounts and lifting the engine to clear the boat hull.
[0025] The present invention may require rotation reversal of a
starter pin of a conventional starter that engages the ring gear of
the flywheel to maintain the same flywheel rotational relationship
relative to the engine crankcase in retrofit applications. As shown
in FIG. 5, in one exemplary embodiment, a bottom plate 220 may be
provided for sealingly closing a bottom section where the flywheel
housing and the engine block interface with one another. If
desired, a suitable seal ring 222 or gasket may be provided to
enhance the, sealing capability of such plate.
[0026] The present invention has been described in terms of the
preferred embodiment, and it is recognized that equivalents,
alternatives, and modifications, aside from those expressly stated,
are possible and within the scope of the appending claims.
* * * * *