U.S. patent application number 14/101392 was filed with the patent office on 2015-06-11 for replaceable nose section for a marine propulsion unit.
This patent application is currently assigned to Caterpillar Inc.. The applicant listed for this patent is Caterpillar Inc.. Invention is credited to Douglas G. Bickelhaupt, Bryan L. Danner, John Schlintz.
Application Number | 20150158570 14/101392 |
Document ID | / |
Family ID | 53270384 |
Filed Date | 2015-06-11 |
United States Patent
Application |
20150158570 |
Kind Code |
A1 |
Schlintz; John ; et
al. |
June 11, 2015 |
REPLACEABLE NOSE SECTION FOR A MARINE PROPULSION UNIT
Abstract
A replaceable nose section for a marine propulsion unit is
disclosed. The marine propulsion unit includes a lower gear case
that extends into the water and includes a lower portion that
includes a shaft section, a prop section, and a nose section. The
shaft section defines a first volume. The nose section includes an
intermediate section that includes an intermediate bulkhead that
defines a second volume. A nose cone is threaded to the
intermediate section and defines a third volume such that the first
and third volumes are not in fluid communication.
Inventors: |
Schlintz; John; (Milwaukee,
WI) ; Danner; Bryan L.; (Oshkosh, WI) ;
Bickelhaupt; Douglas G.; (Oshkosh, WI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Caterpillar Inc. |
Peoria |
IL |
US |
|
|
Assignee: |
Caterpillar Inc.
Peoria
IL
|
Family ID: |
53270384 |
Appl. No.: |
14/101392 |
Filed: |
December 10, 2013 |
Current U.S.
Class: |
416/170R ;
416/245A |
Current CPC
Class: |
B63H 5/125 20130101;
B63H 20/32 20130101 |
International
Class: |
B63H 20/32 20060101
B63H020/32 |
Claims
1. A marine propulsion unit comprising: a lower gear case having a
lower portion, the lower portion comprising: a shaft section
defining a first volume and having an aperture on a front end; a
prop section located abaft the shaft section; a nose section
located forward of said shaft section comprising: an intermediate
portion defining a second volume and having an intermediate
bulkhead, said intermediate portion being engaged to said aperture;
and a nose cone defining a third volume and engaged to said
intermediate portion; wherein said first volume and said third
volume are not in fluid communication.
2. The marine propulsion unit of claim 1 wherein the lower portion
is torpedo-shaped.
3. The marine propulsion unit of claim 1 wherein the lower gear
case forms a portion of a strut that extends below the hull of a
marine vessel
4. The marine propulsion unit of claim 1 wherein said intermediate
portion is threadably engaged to said aperture and said nose cone
is threadably engaged to said intermediate portion.
5. The marine propulsion unit of claim 1 wherein said prop section
comprises front and rear counter-rotating props.
6. The marine propulsion unit of claim 5 wherein the front prop has
three blades and a first diameter and the rear prop has four blades
and a second diameter that is less than the first diameter.
7. The marine propulsion unit of claim 6 wherein the blade area of
the front prop and the blade area of the rear prop are
substantially the same.
8. The marine propulsion unit of claim 5 wherein the front prop has
four blades and a first diameter and the rear prop has five blades
and a second diameter that is less than the first diameter.
9. The marine propulsion unit of claim 8 wherein the blade area of
the front prop and the blade area of the rear prop are
substantially the same.
10. The marine propulsion unit of claim 5 wherein a propeller shaft
anode is threadably attached to a rear prop shaft.
11. A marine propulsion unit comprising: a lower gear case having a
lower portion, the lower portion comprising: a shaft section having
a threaded aperture on a front end; a prop section located abaft
the shaft section; a nose section located forward of said shaft
section comprising: an intermediate portion having an intermediate
bulkhead, said intermediate portion being threadably engaged to
said aperture; and a nose cone threadably engaged to said
intermediate portion.
12. The marine propulsion unit of claim 11 wherein the lower
portion is torpedo-shaped.
13. The marine propulsion unit of claim 11 wherein the lower gear
case forms a portion of a strut that extends below the hull of a
marine vessel.
14. The marine propulsion unit of claim 11
15. The marine propulsion unit of claim 11 wherein said prop
section comprises inner and outer counter-rotating props.
16. The marine propulsion unit of claim 15 wherein the front prop
has three blades and a first diameter and the rear prop has four
blades and a second diameter that is less than the first
diameter.
17. The marine propulsion unit of claim 16 wherein the blade area
of the front prop and the blade area of the rear prop are
substantially the same.
18. The marine propulsion unit of claim 15 wherein the front prop
has four blades and a first diameter and the rear prop has five
blades and a second diameter that is less than the first
diameter.
19. The marine propulsion unit of claim 15 wherein a propeller
shaft anode is threadably attached to a rear prop shaft.
20. A torpedo-shaped section of a marine pod unit comprising: a
shaft section defining a first volume and having a threaded
aperture on a front end; a prop section located abaft the shaft
section; a nose section located forward of said shaft section
comprising: an intermediate portion defining a second volume and
having an intermediate bulkhead, said intermediate portion being
threadably engaged to said aperture; and a nose cone defining a
third volume and threadably engaged to said intermediate portion;
wherein said first volume and said third volume are not in fluid
communication.
Description
TECHNICAL FIELD
[0001] The present disclosure relates to a replaceable nose cone
section for the lower portion of a marine propulsion unit.
BACKGROUND
[0002] Portions of a marine propulsion unit that extend into the
water are susceptible to damage by underwater objects. The portions
that extend below the hull of a marine vessel are especially
susceptible, particularly the leading components such as the nose
section. Therefore, the nose section should be designed to make
replacement of the nose cone easier in the event of damage.
Further, the design of the nose section should prevent oil from the
gear case of the marine propulsion unit from leaking out should the
nose cone become cracked. Similarly, the design of the nose section
should prevent water from intruding into the gear case and causing
severe damage to internal components should the nose cone become
cracked.
[0003] U.S. Pat. No. 2,429,774 to SCHULTZ GEORGE E. et al., issued
Oct. 28, 1947, entitled "Electric outboard motor," discloses a
housing that is threaded to receive a semi-spherically shaped nose.
However, removal of the nose directly exposes the internal
components. If the housing were filled with oil, the oil would have
to be drained in advance of removing the nose. Further, if the nose
were to become cracked from an impact, oil in the gear case would
leak out. This would likely cause severe damage for the internal
components. Similarly, if the nose were to become cracked from an
impact, water would be allowed to intrude into the housing and
cause severe damage for the internal components.
SUMMARY OF THE INVENTION
[0004] A marine propulsion unit is disclosed. The marine propulsion
unit comprises a lower gear case having a lower portion comprising
a shaft section defining a first volume and having an aperture on a
front end, a prop section located abaft the shaft section, and a
nose section located forward of said shaft section. The nose
section comprises an intermediate portion defining a second volume
and having an intermediate bulkhead, said intermediate portion
being engaged to said aperture, and a nose cone defining a third
volume and engaged to said intermediate portion wherein said first
volume and said third volume are not in fluid communication.
[0005] In a second aspect of the current disclosure, a marine
propulsion unit is disclosed comprising a lower gear case having a
lower portion. The lower portion comprises a shaft section having a
threaded aperture on a front end, a prop section located abaft the
shaft section, and a nose section located forward of said shaft
section. The nose section comprises an intermediate portion having
an intermediate bulkhead, said intermediate portion being
threadably engaged to said aperture, and a nose cone threadably
engaged to said intermediate portion.
[0006] In a third aspect of the current disclosure, a
torpedo-shaped section of a marine pod unit is disclosed. The
torpedo-shaped section comprises a shaft section defining a first
volume and having a threaded aperture on a front end, a prop
section located abaft the shaft section, a nose section located
forward of said shaft section. The nose section comprises an
intermediate portion defining a second volume and having an
intermediate bulkhead, said intermediate portion being threadably
engaged to said aperture, and a nose cone defining a third volume
and threadably engaged to said intermediate portion, wherein said
first volume and said third volume are not in fluid
communication.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a view of three aspects of a marine propulsion
unit installed on a marine vessel according to the current
disclosure.
[0008] FIG. 2 is a cut-away view of a marine propulsion unit
according to the current disclosure.
DETAILED DESCRIPTION
[0009] FIG. 1 shows a marine vessel 10 having a marine propulsion
unit 20. The marine propulsion unit 20 includes a lower gear case
30 and a lower portion 60. The lower portion 60 includes a prop
section 90, a shaft section 70, and a nose section 100. The lower
portion 60 may be shaped into the form of a torpedo.
[0010] In one aspect of the current disclosure, the marine
propulsion unit 20 is an outboard drive motor comprising an engine
contained in an enclosure and a lower gear case 30 extending below
the water and having a lower portion 60. The marine propulsion unit
20 is mounted to pivot on the transom of the marine vessel 10 to
provide steering functions.
[0011] In a second aspect of the current disclosure, the marine
propulsion unit 20 is a sterndrive comprising a gear box and a
lower gear case 30 extending below the water and having a lower
portion 60. The gearbox is connected to an engine via a driveshaft
and transmits engine power at a generally 90-degree downward angle
from the engine to the lower gear case 30. The marine propulsion
unit 20 is mounted to pivot on the transom of the marine vessel 10
to provide steering functions.
[0012] In a third aspect of the current disclosure, the marine
propulsion unit 20 is a pod unit, also known as an azimuth
thruster. The pod unit comprises an upper pod unit and a lower gear
case 30. The pod upper unit connects to the engine via a driveshaft
and contains the transmission 50 and steering functions. The lower
gear case 30 extends below the hull and is capable of rotating
around 40 degrees to port or starboard in order to provide steering
functions.
[0013] FIG. 2 shows the lower gear case 30 of a marine propulsion
unit 20. The lower gear case 30 includes a strut 40 that extends
below the waterline 15. The lower gear case 30 contains one or more
driveshafts 200 for transmitting engine power to a propeller via at
least one bevel gear set 270. The lower gear case 30 also includes
bearings 260 for supporting the driveshaft 200 and prop shaft 205.
The lower gear case 30 forms a first volume 140 that is at least
partially filled with oil for lubricating the driveshafts 200, prop
shaft 205, bevel gear sets 270, and bearings 260. The lower gear
case 30 may also include an oil pump 250.
[0014] The lower portion 60 includes a nose section 100 in the
front, a shaft section 70 in the middle, and a prop section 90 at
the rear. The lower portion 60 may be torpedo-shaped. The shaft
section 70 includes a drive shaft 200 for driving the prop shaft
205. If the marine propulsion unit 20 includes a rear prop 230 and
an front prop 240, then the shaft section 70 may contain an inner
prop shaft 210 and an outer prop shaft 220. A skeg 190 may be
attached to the bottom of the shaft section 70. The skeg 190 may be
of break-away type. The front of the shaft section 70 includes a
circular aperture 80. The inside diameter of the shaft section 70
is formed with threads near the aperture 80 and is configured to
threadably accept the intermediate portion 110.
[0015] The prop section 90 is located at the rear of the lower
portion 60 and includes at least one prop 225 driven by a prop
shaft 205. The prop shaft 205 is driven by a bevel gear set 270
driven by a driveshaft 200. In one aspect of the current
disclosure, the prop section 90 may contain a rear prop 230 driven
by an inner prop shaft 210 and an front prop 240 driven by an outer
prop shaft 220. The inner prop shaft 210 and outer prop shaft 220
are driven by a bevel gear set 270 driven by a driveshaft 200. The
use of both a rear prop 230 and front prop 240 increases the thrust
provided by the marine propulsion unit 20. The front prop 240 may
have three blades while the rear prop 230 may have four blades. The
rear prop 230 may need to be smaller in diameter due to flow
velocity at the blade tips. In order for the smaller rear prop 230
to have equal blade area to the front prop 240, the rear prop 230
may have four blades instead of three blades. In another aspect of
the current disclosure, the front prop 240 may have four blades
while the rear prop 230 may have five blades. The prop section 90
may also include a propeller shaft anode 50. The propeller shaft
anode may have a parabolic shape that maximizes hydrodynamic
efficiency while providing anti-corrosion protection.
[0016] The nose section 100 is generally bullet-shaped and located
at the front of the lower portion 60 and includes an intermediate
portion 110 and a nose cone 130.
[0017] The intermediate portion 110 is generally frustoconical and
includes a first engagement portion on the outside diameter of a
rear end and a second engagement portion on the outside diameter of
a front end. The first engagement portion is configured to engage
with the aperture 80. The first and second engagement portions may
engage via a press-fit engagement, may be secured by a set screw or
the like, or may be threaded. If the engagement is threaded, the
intermediated portion 110 may include a threaded portion 170 on the
outside diameter of a rear end and a threaded portion 170 on the
outside diameter of a front end. The intermediate portion 110 also
includes an intermediate bulkhead 120. The intermediate bulkhead
120 forms a fluid-impermeable wall. The intermediate portion 110,
together with the intermediate bulkhead 120, forms a second volume
150. The intermediate portion 110 serves to prevent oil contained
in the lower gear case 30 from escaping through the aperture 80.
The threaded portion 170 on the rear end of the intermediate
portion 110 is configured to engage with the threaded portion 170
of the aperture 80. Provisions are included for an o-ring 180 seal
where the shaft section 70 and the intermediate portion 110 mate
together.
[0018] The nose cone 130 is generally cone or bullet-shaped and
defines a third volume 160. A threaded portion 170 on the inside
diameter of the nose cone 130 is configured to engage with the
threaded portion 170 on the front end of the intermediate portion
110. Provisions are included for an o-ring 180 seal where the nose
cone 130 and the intermediate portion 110 mate together.
INDUSTRIAL APPLICABILITY
[0019] The lower portion 60 is located at the bottom of the lower
gear case 30 and extends into the water and below the hull of the
marine vessel 10. As such, the lower portion 60 is susceptible to
damage from underwater objects such as rocks or shallows. The nose
section 100, being at the front of the lower portion 60, is
particularly susceptible to damage. Therefore, the nose section 100
of the current disclosure is configured with a nose cone 130 that
can be replaced without draining the oil from the lower gear case
30.
[0020] A damaged nose cone 130 can be unscrewed from the
intermediate portion 110. The intermediate bulkhead 120 contains
the oil 35 in the lower gear case 30 while the nose cone 130 is
being removed.
[0021] In the event of a severe crack in the nose cone 130, the
intermediate bulkhead 120 serves to contain the oil 35 in the lower
gear case 30 from leaking out before a repair can be affected.
Preventing a loss of oil 35 prevents a damaged nose cone 130 from
causing severe damage to the gears and bearings in the lower gear
case 30. Similarly, the intermediate bulkhead 120 serves to keep
water from intruding into the gear case 30 before a repair can be
affected. Preventing water intrusion prevents a damaged nose cone
130 from causing severe damage to the gears and bearings in the
lower gear case 30.
* * * * *