JPH01262287A - Power unit for inboard outer machine - Google Patents

Abstract

PURPOSE:To widen a living space in a hull as well as to aim at a stable engine combustion by using a horizontal opposed type 2-cycle engine as an engine for an inboard outer machine, and installing an intake port in the upper part of a crankcase being held between two cylinder banks. CONSTITUTION:A power unit for an inboard outer machine, setting up an engine in the hull and driving a propulsion unit installed at the outside of the hull, a horizontal opposed type 2-cycle engine 12 is adopted as the engine. An intake port 30 is installed in the upper part of a crankcase 29 being held between symmetrical cylinder banks 28A, 28B, and air intake takes place by way of an intake silencer box 34 and a carburetor 33 via an intake manifold 32 and a reed valve 31. Height and length of the engine are made smaller and thereby a living space in the hull can be made larger without changing length of the hull. In addition, this air intake is uniformly distributed to symmetrical cylinders so that a stable engine combustion is securable.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a moving crab knee for an inboard/outboard motor.

[Prior Art] Inboard-outboard motors use a power unit in which an engine is disposed inside the hull, and the engine drives a propulsion device provided outside the hull.

Conventionally, the engines constituting the above power unit are 4
A cycle engine is used, and this four-cycle engine is installed in the rear center of the hull. Figure 6 is a schematic diagram showing the appearance of the hull in which this engine is installed.
is the engine box, and 2 on either side of it are the rear seats.

[Problem to be Solved by the Invention] However, the above conventional inboard/outboard motor has the following problems.

■The external shape of the engine protrudes significantly upward and forward, narrowing the living space inside the hull.

■Due to the above (■), the engine box becomes larger, and the rear seat cannot be made into a bench (continuous from side to side so that a person can lie down).

Furthermore, in the case of inboard/outboard motors, it is desirable to stabilize the combustion state of the engine in order to stabilize low-load operating states such as during trolling.

The object of the present invention is to widen the living space inside the hull by improving the power unit, to make it possible to make the rear seat a bench if desired, and to stabilize the combustion state of the engine.

[Means for Solving the Problems] The present invention provides a power unit for an inboard/outboard motor in which an engine is disposed inside the hull and a propulsion device provided outside the hull is driven by the engine, wherein the engine is a horizontally opposed two-stroke engine. An engine is used, and an intake port is provided in the upper part of the crank chamber sandwiched between two cylinder banks of the engine.

[Effect] According to the present invention, there are the following effects.

■By using a horizontally opposed two-stroke engine,
The height and length of the engine in the longitudinal direction can be reduced, and the living space inside the hull can be increased without changing the length of the hull.

(2) The engine is placed under the rear seat, for example, so the conventional engine box can be abolished, and if desired, the rear seat can be easily converted into a bench.

■By providing the intake port at the top of the crank chamber between the left and right cylinder banks, it is possible to ensure equal distribution of intake air to the left and right cylinder banks, and also to stabilize the combustion state of the engine.

[Example] Fig. 1 is a side view showing one embodiment of the present invention, and Fig. 2 is a side view showing one embodiment of the present invention.
Figure 3 is a plan view showing the engine, Figure 4 is a front view showing how accessories are attached to the engine, and Figure 5 is a cross-sectional view taken along the line ■-■ in the figure. It is a schematic diagram.

As shown in FIG. 1, the inboard/outboard motor 10 has an engine 12 disposed inside a hull 11, and the engine 12 drives a propulsion unit (propulsion device) 13 provided outside the hull 11.

In the propulsion unit 13, a gimbal ring 15 is rotatably connected to a gimbal housing 14 attached to the stern plate 11A of the hull 11, and the propulsion unit 13 is rotatably connected to the gimbal ring 15. 16 is a tilting cylinder device provided between the gimbal ring 15 and the propulsion unit 13.

The engine 12 is fixed to a mount (not shown) provided on the bottom 11B of the hull 11. The output shaft 17 of the engine 12 has a joint 18. The base shaft 20 of the propulsion unit 13 is connected via the universal joint 19, and the upper gear train 2
1. Intermediate shaft 20A.

A propeller shaft 23 is connected via a lower gear train 22. The upper gear train 21 or the lower gear train 22 constitutes a forward/reverse switching mechanism, and a propeller shaft 23 is provided with a propeller 24 .

As shown in FIGS. 1 to 3, the engine 12 consists of a horizontally opposed two-stroke engine, and includes a crankcase 25, left and right cylinder blocks 26 provided on both sides of the crankcase 25, and each cylinder block 26. With the provided cylinder head 27, the engine body 1
It constitutes 2A. 100 is a flywheel.

The engine 12 has left and right cylinder banks 28A and 28B.
three cylinders each are formed, and both cylinder banks 28A, 2
An intake port 30 is provided at the upper part of the crank chamber 29 sandwiched between the crank chambers 8B and 8B. A reed valve 3 is provided at the intake port 30 of the engine 12.
An intake manifold 32 is connected via 1. The intake manifold 32 is bent by 90 degrees, and a carburetor 33 and an intake silencer box 34 are connected to a connection port 32A that opens laterally. As a result, one cylinder bank 28A
A carburetor 33 and an intake silencer box 34 are installed above the engine.

The engine 12 is provided with scavenging passages 35 that communicate between each cylinder and the crank chamber 29 at, for example, three positions on the upper and side parts of the left and right cylinder blocks 26.
An exhaust port 36 for each cylinder is provided on the lower side of the cylinder 6.

Exhaust ports 36 provided on the lower side of the left and right cylinder blocks 26
Left and right exhaust manifolds 37 are connected to the left and right exhaust manifolds 37, left and right exhaust pipes 38 having a U-shape are connected to the flywheel side of each exhaust manifold 37, and both exhaust pipes 38 are connected to an exhaust silencer box 39. The exhaust silencer box 39 is disposed below the crankcase 25 in a space sandwiched between the left and right exhaust manifolds 37. That is, the exhaust pipe line connected to the exhaust port 36 of the engine 12 is arranged in the area surrounded by the engine body 12A and the bottom 11B, as described above.

The exhaust silencer box 39 communicates with an exhaust passage provided inside the propulsion unit 13 via a rising exhaust pipe 40 or the like, and discharges the exhaust gas of the engine 12 from the boss portion of the propeller 24 into the water. .

Further, the engine 12 has auxiliary equipment such as an alternator 41, a starter motor 42, a water pump 43, etc. installed on the upper part of the engine main body 12A. The alternator 41 is installed in the upper part of the cylinder block 26 that constitutes the cylinder bank 28B on the side opposite to the cylinder bank 28A in which the intake system is installed, and the starter motor 42 is installed in the crankcase 25.
installed next to the intake manifold 32 at the top of the
The water pump 43 is installed in front of the intake manifold 32 in the upper part of the crankcase 25.

Note that the hull 11 in which the engine 12 is disposed has a fifth
As shown in the figure, a benched rear seat 44 can be provided above the engine 12.

Next, the operation of the above embodiment will be explained.

(2) By using the horizontally opposed two-stroke engine 12, the height and longitudinal length of the engine 12 can be reduced, and the living space inside the hull can be increased without changing the length of the hull 11.

(2) By placing the engine 12 under the rear seat 44, for example, the conventional engine box can be abolished, and the rear seat 44 can be turned into a bench.

■ By providing the intake port 30 in the upper part of the crank chamber 29 sandwiched between the left and right cylinder banks 28A and 28B, it is possible to ensure equal distribution of intake air between the left and right cylinder banks 28A and 28B, and to stabilize the combustion state of the engine 12. can also be achieved.

Further, in the above-mentioned inboard/outboard motor 10, the alternator 41
, starter motor 42. Since the auxiliary equipment such as the water pump 43 is installed on the upper part of the engine main body 12A, the following effects can be obtained.

■Auxiliary equipment can be protected from corrosion and electrical troubles caused by bilge (seawater) accumulating on the bottom 11B of the ship.

■Auxiliary equipment can be easily maintained above the engine 12.

Since the engine 12 of the inboard/outboard motor 10 cannot be easily removed from the hull 11 and must be maintained while attached to the hull 11, the auxiliary machinery must be visible and freely accessible from above the engine 12. It is important to be.

■The advantage of the horizontally opposed engine 12, which is the compactness of the engine, is not compromised by the layout of auxiliary equipment, and the entire engine can be made compact.

[Effects of the Invention] As described above, according to the present invention, by improving the power unit, the living space inside the hull can be expanded, the rear seats can be made into a bench if desired, and the combustion state of the engine can be stabilized. can also be achieved.

[Brief explanation of the drawing]

FIG. 1 is a side view showing one embodiment of the present invention, and FIG. 2 is a side view showing one embodiment of the present invention.
A sectional view taken along line II-II in the figure, Figure 3 is a plan view showing the engine, Figure 4 is a front view showing how auxiliary equipment is attached to the engine, and Figure 5 shows how the engine is installed in the hull. The schematic diagram, FIG. 6, is a schematic diagram showing the appearance of a hull in which a conventional engine is installed. DESCRIPTION OF SYMBOLS 10... Inboard/outboard motor, 11... Hull, 12... Engine, 13... Propulsion unit, 28A, 28B... Cylinder bank, 29... Crank chamber, 30... Intake port.

Claims (1)

[Claims] (1) In an inboard-outboard power unit in which an engine is disposed inside the hull and the engine drives a propulsion device provided outside the hull, a horizontally opposed two-stroke engine is used as the engine, and two cylinders of the engine are used. A power unit for an inboard/outboard motor that features an intake port located above the crank chamber sandwiched between banks.