JPH0194096A - Boat propeller - Google Patents

Abstract

PURPOSE: To reduce costs by providing an exhaust passage coupled between an engine in a boat and a drive part having a lower unit extending up to stern under the boat, and passing exhaust through a boat hull to the lower unit. CONSTITUTION: A lower unit 18 has an exhaust outlet 42 provided within a trim fin under an anti-cavitation plate 30, and exhaust is exhausted backward unto water therefrom. A lower unit adapter 19 removably mounted on the lower unit 18 communicates the exhaust to the outlet 42. The adapter 19 forms the cover of the lower unit 18 matching an upwardly open chamber 43 and has a rigid curved exhaust pipe 44 forming a coupled adapter passage passing the exhaust to the chamber 43. The lower unit 18 and the adapter 19 have a n exhaust passage extending between the exhaust outlet 42 and a front exhaust inlet 47. The engine exhaust pipe of an engine exhaust system 48 is coupled from the engine 12 to an exhaust pipe connector 51 provided on a front vertical wall near the exhaust inlet 47.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an exhaust system for boat propulsion, and more particularly to a boat propulsion device having an engine inside the boat and a steering and trimmable drive on the underside of the boat. Regarding the exhaust system.

[Conventional technology]

A conventional boat propulsion system for steering and trimming a drive includes a stern drive and an outboard motor.

The stern drive section includes all engines inside the boat and a drive section at the rear of the boat. The exhaust system in the stern beating part is
It connects from the engine to the transom mount, to the exhaust bellows under the gimbal, to an internal passageway into the lower unit, and to the exhaust at the rear of the lower unit.

An outboard motor is a unit assembly of an engine and a drive section that is mounted on the outside of a boat. An exhaust passage is installed internally from the engine to the lower unit.

[Problem to be solved by the invention]

The exhaust systems of prior art boat propulsion systems are configured to match the geometry of the structure of the propulsion system.

Therefore, while the propulsion system itself is already complex, this complexity is further doubled by the exhaust system.

The cost will also be higher.

U.S. Patent No. 2,976,836 to L. J. Fageol et al.
Other conventional propulsion systems, such as those described in U.S. Pat.

[Means to solve the problem]

The present invention provides an exhaust system for a boat propulsion device in which a portion of the drive is housed in a cavity on the underside of the boat. The present invention provides an exhaust passage coupling between an engine inside the boat and a drive having a lower unit extending to the stern on the underside of the boat, the exhaust passage being directed through the boat hull and into the lower unit. Make it. A flexible section bellows is provided between the lower unit and the cavity surface to accommodate the tilting of the lower unit with respect to the bottom of the boat during steering and trim/tilt operations. This minimizes distortion of the exhaust system seam when operating the boat propulsion device. The rigid exhaust pipe inside the boat and the flexible exhaust bellows on the outside of the boat are connected by a boat exhaust connector mounted on a vertical wall. This boat exhaust connector offers many advantages, including ease of boat emplacement and installation of the exhaust system.

[Embodiment] L-type sleeping device As shown in FIGS. 1 to 4, a boat propulsion device or L-type sleeping device 10 is mounted on a ship or a boat 11. Boat propulsion device 10 includes an engine 12, a mounting assembly 13, and a drive section 14.

Engine 12 may be a two or four cycle internal combustion engine. In a preferred embodiment, an 85 horsepower engine used in US Navy outboard motors is used. If more horsepower is required, a US Navy outboard 125 horsepower engine may be used.

The drive section 14 includes a rudder assembly 15, a trimming assembly 16 with a trim adjustment system 17, a propeller drive lower unit 18, a lower unit adapter 19, and a drive transmission device (not shown). Drive section 14
rotates left and right about a vertical axis 20 passing through the mounting assembly 13 for steering, and pivots up and down about a horizontal axis 21 for trim/tilt.

The rudder assembly 15 includes the steering member 22 and the boat 1.
includes a steering arm 23 for rotating a steering member 22 to steer the vehicle.

The trimming assembly 16 includes a trunnion 24 on the lower unit adapter 19 that connects the adapter 19 to the steering member 22 with a horizontal trunnion pivot 25.
Mounted so that it can pivot. Trimming assembly 19 also uses trim adjustment system 17. This adjustment system 1
7 includes a hydraulic trim cylinder 26 coupled between a cylinder upper pivot 27 on the steering member 22 and a cylinder lower pivot 28 on the lower unit 18. This hydraulic trim cylinder 26 is operated during trim/tilt to pivot the drive unit 14 up and down.

The lower unit 18 includes a propeller 29, an anti-cavitation plate 30, and a trim fin 31 below this plate 30. The lower unit 18 has a well-known structure used in outboard motors.

A preferred lower unit is the 85 horsepower lower unit used in military outboard motors manufactured by US Marine Corporation. Alternatively, it could be a 125 horsepower lower unit used in military outboard motors.

The lower unit adapter 19 is mounted on the top of the lower unit 18 and connects the lower unit 18 to the trunnion pivot 25.
The trimming assembly 16 is removably or adjustably attached to the trimming assembly 16 at a point.

Boat - Boat 11 includes a planing hull 32 and a generally vertical transom 33. Hull 32 includes a planed bottom surface 34 and a cavity 35 adjacent transom 33 . A cavity 35 extends upwardly into the hull 32 and opens at its end into a notch 36 in the transom 33.

The cavity 35 has a first left side wall 37, a second right side wall 38, and a third front side wall 39. The front side wall 39 is preferably]
Like Ransom 33, it is made vertical.

In order to make the hull planing surface 34 in front of the drive part 14 as large as possible, the front side wall 39 is placed as far back as possible towards the drive part 14 . Drive unit mounting assembly 13
A hole 40 for fitting is formed in the top 41 of the cavity 35.

The lower unit 18 of the Tsuji Stem has a cavitation prevention plate 3.
0 is provided with an exhaust outlet 42 provided in the trim fin at the lower side of the trim fin. This known exhaust outlet location directs the exhaust air out of the boat and into the water. An upwardly open chamber 43 in the lower unit 18 feeds an exhaust outlet 42 .

A lower unit adapter 19, removably mounted on the lower unit 18 as previously described, communicates the exhaust air to the outlet 42. The lower unit adapter 19 has an upper opening chamber 43.
A rigid bent exhaust pipe 44 is provided which forms a cover of the lower unit 18 that mates with the lower unit 18 and creates a coupling adapter passageway 45 for passing the exhaust air to the chamber 43.

A rigid bent exhaust pipe 44 bends around the adapter trunnion 24 of the trimming assembly 16. The bent exhaust pipe 44 has a rear end connected to the chamber 43 and a front end connected to the connecting end 4.
It has 6. This front end is located approximately at the front end of the lower unit 18.

In other words, the lower unit 18 and the adapter 19 provide a closed exhaust passage extending between the rear exhaust outlet 42 and the front exhaust port 47.

Engine exhaust system 48 includes an engine exhaust pipe 49 . This exhaust pipe is connected from the engine 12 to the face of the front vertical wall 39 which is provided as close as possible to the front exhaust port 47 of the bent exhaust pipe 44 .

The vertical front side wall 39 has an opening or exhaust cutout 50 and within this cutout 50 an exhaust pipe connector 51 is installed.
is sealed and shelved. The exhaust pipe connector 51 includes a connector housing 52 having a mounting flange 53 that is sealed and mounted on the side surface around the exhaust cutout, and an inner connector portion 54.
, and an outer connector portion 55. As shown in FIGS. 5-7, the connector housing 52 extends through the exhaust cutout 50 and into the boat 11.
The coupling space of the outer connector portion 55 in the front side wall 39 located at the rear is widened.

Engine exhaust pipe 49 is coupled to inner connector portion 54 . Engine exhaust pipe 49 is preferably rigid, but may include flexible tubing sections.

A flexible exhaust pipe, preferably a flexible exhaust bellows 56, includes:
A connection is made between the outer connector portion 55 and the bent exhaust pipe joining end 46 . Exhaust bellows 56 is a tubular or hollow member made of an exhaust resistant material that maintains a non-sagging shape when flexed. Exhaust bellows 56 extends between outer connector portion 55 in front side wall 39 and the front end of lower unit 18 .

Exhaust bellows 56 can have its front end extending into connector housing 52 . Therefore.

Using a longer exhaust bellows 56, the lower unit 18
The space between the front wall 39 and the front wall 39 can be made shorter.

As shown in FIG. 6, when the drive section 14 is steered, the lower unit end of the exhaust bellows 56 swings left and right. As shown in FIG. 7, the exhaust bellows 56 swings up and down during trim/tilt.

The positioning of the exhaust bellows 56 as described above makes the bending change of the exhaust passage formed between the lower unit 18 and the boat 11 gentle during steering and trim/tilt, and lengthens the bending life of the exhaust passage. And the exhaust bellows is not easily visible from the bottom of the boat 11.

[Brief explanation of the drawing]

FIG. 1 is a side view of a boat propulsion device and boat equipped with an exhaust system of the present invention; FIG. 2 is a rear view of the boat propulsion device of the present invention showing the entrance of the lower unit exhaust passage; FIG. 1 and 5, a left side view of the boat propulsion device of FIG. 2 showing the lower unit exhaust passage; FIG. 4 is a front view of the boat propulsion device of the present invention showing the lower unit exhaust passage outlet; FIG. 5 can be seen in FIGS. 1 and 3. 6 is an enlarged plan view of the flexible portion of the exhaust system of FIG. 1 during steering; FIG. 1 is an enlarged side view of the flexible portion of the exhaust system of FIG. 1 during trimming; FIG. 10... Boat propulsion device, 11... Boat, 12.
... Engine, 13... Mounting assembly, 14... Drive unit, 15... Rudder assembly, 16... Trimming assembly. 17... Trim adjustment system, 18... Lower unit, 29... Propeller, 32...
...Hull, 33...Transom, 35...Cavity, 42...Exhaust outlet, 44...Exhaust pipe, 48...
- Exhaust system, 51... Connector, 56... Bellows.

Claims (1)

[Claims] 1. A propulsion device for a boat, comprising: a mounting assembly for penetrating the generally flat bottom of the boat and attaching the propulsion device; an engine installed inside the boat; a propeller drive mounted below a generally planar bottom surface, the drive being drivingly connected to the engine via the mounting assembly, the drive being connected between an exhaust inlet and an outlet; a propeller drive including a lower unit having an exhaust passageway therethrough; a rudder mount coupling the drive to the mount assembly, the rudder mount including a generally vertical section within the mount assembly; a rudder assembly configured to rotate about an axis; a trimming assembly coupling the drive to the rudder assembly for a limited range of horizontal oscillation; and a trimming assembly configured to rotate the engine and the rudder assembly. An exhaust passage device including a flexible portion coupled to a drive portion, the flexible portion providing exhaust coupling during steering and trimming of the propeller drive portion. Propulsion device. 2. the lower unit includes an anti-cavitation plate, and the outlet is provided below the anti-cavitation plate to inject the exhaust air rearwardly from the boat;
The propulsion device according to claim 1. 3. The propulsion system of claim 1, wherein the lower unit exhaust passage includes a portion passing around the steering and trimming assembly, and the inlet of the lower unit faces toward the front of the boat. 4. The propulsion of claim 1, wherein the flexible portion of the exhaust passage device extends at least between the lower unit and the bottom of the boat, and the exhaust passage device includes a sealed portion at the bottom of the boat. Device. 5. The propulsion device according to claim 4, wherein the sealed portion is an exhaust connector that seals and passes through a hole in the bottom of the boat. 6. In a boat, a hull having a propeller drive including a cavity extending upwardly from the bottom of the boat, the cavity having a hole in the top thereof, the hull being installed under the hull and within the cavity; an individually trimmable and steerable propeller drive mounted through the hole in the top of the cavity, the propeller drive including a lower unit; and a coupling between the lower unit and the cavity. an exhaust flexible passageway section, the flexible passageway section creating a closed exhaust passageway during steering and trimming operations of the drive section. 7. The boat of claim 6, wherein the cavity includes an exhaust connector extending into the boat, and wherein the flexible passageway portion couples between the lower unit and the exhaust connector. 8. The boat of claim 7, wherein said cavity has a generally vertical front wall through which said flexible passageway portion is located. 9. In a boat, the propeller drive unit provided in the hull includes a cavity extending upward from the bottom of the boat and formed inside the hull, and the propeller drive unit is installed in a hole formed at the top of the cavity, and the propeller drive unit is installed in a hole formed at the top of the cavity. A boat with an exhaust connector mounted on the vertical front wall.