SHIP PROPULSION MACHINE

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2024-118469 filed on Jul. 24, 2024, the entire content of which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a ship propulsion machine including an engine and a motor as power sources for rotating a propeller.

BACKGROUND ART

A hybrid type ship propulsion machine is known which rotates a propeller by using power of an engine (internal combustion engine) and power of a motor (electric motor). JP2020-189556A describes a hybrid type outboard motor.

The hybrid type ship propulsion machine includes an engine serving as a first power source for rotating a propeller, a motor serving as a second power source for rotating the propeller, an inverter for controlling driving of the motor, and a power switching mechanism for switching a power source that rotates the propeller between the engine and the motor. The engine, motor, inverter, and power switching mechanism are all large-sized devices with substantial volume.

As described above, the hybrid type ship propulsion machine includes a large number of large devices as compared with a non-hybrid type ship propulsion machine, that is, a ship propulsion machine in which only the engine is used as the power source for rotating the propeller, or only the motor is used as the power source. Therefore, there is a problem that the hybrid type ship propulsion machine is more likely to be larger as compared with the non-hybrid type ship propulsion machine.

SUMMARY OF INVENTION

Aspect of non-limiting embodiments of the present disclosure relates to reduce the size of a hybrid type ship propulsion machine.

Aspects of certain non-limiting embodiments of the present disclosure address the features discussed above and/or other features not described above. However, aspects of the non-limiting embodiments are not required to address the above features, and aspects of the non-limiting embodiments of the present disclosure may not address features described above.

According to an aspect of the present disclosure, there is provided a ship propulsion machine for propelling a ship, the ship propulsion machine including:

• • a propeller;
  • an engine configured to rotate the propeller, the engine serving as a first power source;
  • a motor configured to rotate the propeller, the motor serving as a second power source;
  • an inverter configured to control driving of the motor;
  • an engine drive shaft connected to a crank shaft of the engine;
  • a motor drive shaft connected to an output shaft of the motor;
  • a transmission shaft connected to a propeller shaft provided with the propeller; and
  • a power switching mechanism configured to switch a connection mode of the engine drive shaft, the motor drive shaft, and the transmission shaft to switch a power source for rotating the propeller between the engine and the motor,
  • in which the engine is arranged vertically such that an extension direction of a rotation axis of the crank shaft is in an upper-lower direction,
  • in a state where the engine disposed vertically, the engine includes a lower extension portion extending downward from a front portion of an engine body of the engine or a middle portion of an engine body of the engine in a front-rear direction,
  • the engine drive shaft is arranged so as to extend in the upper-lower direction in front of the lower extension portion,
  • the motor is arranged below a rear portion of the engine body such that an extension direction of the output shaft is in the front-rear direction and a position of the output shaft is further downward than the lower extension portion,
  • the motor drive shaft is arranged so as to extend in the front-rear direction below the lower extension portion,
  • the power switching mechanism is arranged below a lower end of the engine drive shaft and in front of a front end of the motor drive shaft, and
  • the inverter is arranged behind the lower extension portion and between the rear portion of the engine body and the motor.

BRIEF DESCRIPTION OF DRAWINGS

Exemplary embodiment(s) of the present invention will be described in detail based on the following figures, wherein:

FIG. 1 is an explanatory diagram illustrating a ship propulsion machine according to an embodiment of the present disclosure;

FIG. 2 is an explanatory diagram illustrating an arrangement of components of the ship propulsion machine according to the embodiment of the present disclosure;

FIG. 3 is an explanatory diagram illustrating an engine of the ship propulsion machine according to the embodiment of the present disclosure;

FIG. 4 is an explanatory diagram illustrating a cooling structure of the ship propulsion machine according to the embodiment of the present disclosure;

FIG. 5 is an external view illustrating a part of the engine, a motor, an inverter, a heat exchanger, an inverter bracket, and the like in the ship propulsion machine illustrated in FIG. 1 as viewed from the left;

FIG. 6 is an external view illustrating the motor, the inverter, the heat exchanger, the inverter bracket, and the like in the ship propulsion machine according to the embodiment of the present disclosure as viewed from the rear;

FIG. 7 is an external view illustrating a state in which the part of the engine, the motor, the inverter, the heat exchanger, the inverter bracket, and the like are separated in the ship propulsion machine according to the embodiment of the present disclosure;

FIG. 8A is an external view illustrating the inverter bracket in the ship propulsion machine according to the embodiment of the present disclosure as viewed from the left;

FIG. 8B is an external view illustrating the inverter bracket as viewed from above;

FIG. 8C is an external view illustrating the inverter bracket as viewed from the front;

FIG. 9A is an external view illustrating the inverter bracket and the inverter in the ship propulsion machine according to the embodiment of the present disclosure as viewed from the left; and

FIG. 9B is a cross-sectional view illustrating the inverter bracket and the inverter cut along a cutting line IXb-IXb in FIG. 9A as viewed from the front.

DESCRIPTION OF EMBODIMENTS

A ship propulsion machine according to an embodiment of the present disclosure is a hybrid type ship propulsion machine for propelling a ship, including: a propeller; an engine serving as a first power source configured to rotate the propeller; a motor serving as a second power source configured to rotate the propeller; an inverter configured to control driving of the motor; an engine drive shaft connected to a crank shaft of the engine; a motor drive shaft connected to an output shaft of the motor; a transmission shaft connected to a propeller shaft provided with the propeller; and a power switching mechanism configured to switch a power source for rotating the propeller between the engine and the motor by switching a connection mode of the engine drive shaft, the motor drive shaft, and the transmission shaft.

In the ship propulsion machine according to the present embodiment, the engine is arranged vertically such that an extension direction of a rotation axis of the crank shaft is in an upper-lower direction. The engine includes, when being arranged vertically, a lower extension portion extending downward from a front portion of an engine body of the engine or a middle portion in a front-rear direction. The engine drive shaft is arranged so as to extend in the upper-lower direction in front of the lower extension portion of the engine. The motor is arranged below a rear portion of the engine body such that an extension direction of the output shaft is in the front-rear direction and a position of the output shaft is further downward then the lower extension portion of the engine. The motor drive shaft is arranged so as to extend in the front-rear direction below the lower extension portion of the engine. The power switching mechanism is arranged below a lower end of the engine drive shaft and in front of a front end of the motor drive shaft. The inverter is arranged behind the lower extension portion of the engine and between the rear portion of the engine body and the motor.

By arranging the engine vertically such that the extension direction of the rotation axis of the crank shaft is in the upper-lower direction, and arranging the engine drive shaft such that the engine drive shaft extends in the upper-lower direction in front of the lower extension portion of the engine, the engine drive shaft can be arranged along a front surface of the lower extension portion of the engine and can be brought close to the front surface of the lower extension portion of the engine.

By arranging the motor below the rear portion of the engine body such that the extension direction of the output shaft is in the front-rear direction and the position of the output shaft is below the lower extension portion of the engine, and arranging the motor drive shaft such that the motor drive shaft extends in the front-rear direction below the lower extension portion of the engine, the motor drive shaft can be arranged along a lower surface of the lower extension portion of the engine and can be brought close to the lower surface of the lower extension portion of the engine.

Further, by arranging the power switching mechanism below the lower end of the engine drive shaft and in front of the front end of the motor drive shaft, the power switching mechanism can be arranged close to a front lower corner of the lower extension portion of the engine.

The lower extension portion extends downward from the front portion of the engine body or the middle portion in the front-rear direction in a state in which the engine is arranged vertically, and thus in the state in which the engine is arranged vertically, a rear surface of the engine body is positioned further rearward than a rear surface of the lower extension portion of the engine. That is, the rear portion of the engine body protrudes further rearward than the lower extension portion of the engine. Therefore, when the motor is arranged below the rear portion of the engine body, a space is formed behind the lower extension portion and between the rear portion of the engine body and the motor. By arranging the inverter behind the lower extension portion of the engine and between the rear portion of the engine body and the motor, that is, by arranging the inverter in the space, the inverter can be brought close to the lower extension portion of the engine, the rear portion of the engine body, and the motor, respectively.

As described above, in the ship propulsion machine according to the present embodiment, the engine drive shaft can be arranged along the front surface of the lower extension portion of the engine and can be brought close to the front surface of the lower extension portion of the engine, the motor drive shaft can be arranged along the lower surface of the lower extension portion of the engine and can be brought close to the lower surface of the lower extension portion of the engine, the power switching mechanism can be arranged close to the front lower corner of the lower extension portion of the engine, and the inverter can be brought close to the lower extension portion of the engine, the rear portion of the engine body, and the motor, respectively. That is, according to the ship propulsion machine of the present embodiment, the engine, the motor, the inverter, the engine drive shaft, the motor drive shaft, and the power switching mechanism can be arranged in a compact manner with minimal gaps between each component. Accordingly, it is possible to reduce the size of a hybrid type ship propulsion machine.

Embodiment

Hereinafter, an embodiment of a ship propulsion machine 1 according to the present disclosure will be described with reference to the drawings. In the description of the embodiment, when describing directions of upper (Ud), lower (Dd), front (Fd), rear (Bd), left (Ld), and right (Rd), arrows drawn at the lower right of each figure are followed for the sake of convenience of description.

(Ship Propulsion Machine)

FIG. 1 illustrates the ship propulsion machine 1. FIG. 2 illustrates an arrangement of components of the ship propulsion machine 1. FIG. 3 illustrates an engine 4 of the ship propulsion machine 1.

The ship propulsion machine 1 is a machine for propelling a ship. The ship propulsion machine 1 according to the present embodiment is an outboard motor and is attached to a ship. As illustrated in FIGS. 1 and 2, the ship propulsion machine 1 includes propellers 2, propeller shafts 3 to which the propeller 2 is fixed, an engine 4, serving as a first power source, configured to rotate the propeller 2, a motor 17, serving as a second power source, configured to rotate the propeller 2, and an inverter 19 configured to control driving of the motor 17.

The propeller 2 and the propeller shaft 3 are arranged at a lower portion of the ship propulsion machine 1, and are positioned below the water surface in a state where the ship propulsion machine 1 is attached to a ship. The engine 4, the motor 17, and the inverter 19 are arranged in a portion from an upper portion to a middle portion in an upper-lower direction of the ship propulsion machine 1, and are positioned above the water surface in a state in which the ship propulsion machine 1 is attached to a ship.

As illustrated in FIG. 3, an engine body 5 of the engine 4 includes a crankcase 7 provided with a crank shaft 6, a cylinder block 9 provided with pistons 8, a cylinder head 13 provided with intake valves 10, exhaust valves 11, and a camshaft 12, and an intake manifold 14 for supplying air to a combustion chamber, and the like. The engine body 5 is provided with an oil pan 15 for storing engine oil.

As illustrated in FIG. 3, the engine 4 is arranged vertically such that an extension direction of a rotation axis of the crank shaft 6 is in the upper-lower direction. The engine 4 is arranged such that the crankcase 7 is on a front side and the intake manifold 14 is on a rear side. In a state where the engine 4 is vertically arranged in this manner, the oil pan 15 extends downward from a front portion of the engine body 5 or a middle portion in a front-rear direction. A recessed portion 16 recessed upward is provided at a rear portion of a lower surface of the oil pan 15. A rear portion 5A of the engine body 5 (a portion further upward than the oil pan 15 in the engine 4) protrudes further rearward than the oil pan 15. A rear surface of the rear portion 5A of the engine body 5 is positioned further rearward than the rear surface of the oil pan 15. The oil pan 15 is a specific example of a “lower extension portion”.

As illustrated in FIG. 2, the motor 17 is arranged below the rear portion 5A of the engine body 5 such that an extension direction of an output shaft 18 is in the front-rear direction and a position of the output shaft 18 is below the oil pan 15. An upper portion of a front portion of the motor 17 is arranged in the recessed portion 16 of the oil pan 15.

The inverter 19 is arranged behind the oil pan 15 and between the rear portion 5A of the engine body 5 and the motor 17. As will be described later, the ship propulsion machine 1 includes a heat exchanger configured to that cool a cooling medium for cooling the motor 17 and the inverter 19. The heat exchanger 43 is arranged behind the oil pan 15 and between the rear portion 5A of the engine body 5 and the inverter 19.

The ship propulsion machine 1 further includes an engine drive shaft 21, a motor drive shaft 22, a transmission shaft 23, a power switching mechanism 24, and a rotation transmission mechanism 25.

The engine drive shaft 21 is arranged so as to extend in the upper-lower direction in front of the oil pan 15. The engine drive shaft 21 is connected to the crank shaft 6 of the engine 4 via a gear, and is configured to be rotated by receiving rotation of the crank shaft 6.

The motor drive shaft 22 is arranged so as to extend in the front-rear direction below the oil pan 15. The motor drive shaft 22 is connected to the output shaft 18 of the motor 17 and is configured to be rotated integrally with the output shaft 18.

The transmission shaft 23 is arranged so as to extend in the upper-lower direction below the engine drive shaft 21. The transmission shaft 23 is connected to the propeller shaft 3 via the rotation transmission mechanism 25.

The power switching mechanism 24 is arranged below a lower end of the engine drive shaft 21 and in front of a front end of the motor drive shaft 22. The power switching mechanism 24 is configured to switch a connection mode of the engine drive shaft 21, the motor drive shaft 22, and the transmission shaft 23 to switch a power source for rotating the propeller 2 between the engine 4 and the motor 17. The power switching mechanism 24 includes a clutch for switching the connection mode of the engine drive shaft 21, the motor drive shaft 22, and the transmission shaft 23. As the engine drive shaft 21 and the transmission shaft 23 are connected to each other by the clutch, the rotation of the engine drive shaft 21 is transmitted to the transmission shaft 23. As a result, the propeller 2 rotates by the power of the engine 4. As the motor drive shaft 22 and the transmission shaft 23 are connected to each other by the clutch, the rotation of the motor drive shaft 22 is transmitted to the transmission shaft 23. As a result, the propeller 2 rotates by the power of the motor 17. As both the engine drive shaft 21 and the motor drive shaft 22 are connected to the transmission shaft 23 by the clutch, the rotation of the engine drive shaft 21 and the motor drive shaft 22 is transmitted to the transmission shaft 23. As a result, the propeller 2 is rotated by the power of the engine 4 and the motor 17.

The rotation transmission mechanism 25 is arranged in a front portion of the lower portion of the ship propulsion machine 1. The rotation transmission mechanism 25 is a mechanism configured to transmit the rotation of the transmission shaft 23 to the propeller shaft 3. The rotation transmission mechanism 25 includes a first gear mechanism 26 configured to switch a rotation direction of the propeller shaft 3. The ship propulsion machine 1 according to the present embodiment adopts a contra-rotating propeller, and includes two propellers 2 and two propeller shafts 3 to which the propellers 2 are respectively fixed. The rotation transmission mechanism 25 includes a second gear mechanism 27 configured to transmit the rotation of the transmission shaft 23 to the two propeller shafts 3 such that the rotation directions of the propeller shafts 3 are opposite to each other.

(Cooling Structure)

FIG. 4 illustrates a cooling structure of the ship propulsion machine 1. As illustrated in FIG. 4, the ship propulsion machine 1 includes a liquid-cooled cooling structure 31 configured to cool the engine 4, the motor 17, and the inverter 19.

The cooling structure 31 includes a water intake port 32, a first cooling water supply passage 33, a water pump 34, an engine cooling mechanism 35, a first cooling water discharge passage 36, a water discharge port 37, and a cooling water temperature control valve 38.

The water intake port 32 is a port for taking water (for example, seawater) outside the ship propulsion machine 1 as cooling water into the ship propulsion machine 1. The water intake port 32 is provided at a lower portion of the ship propulsion machine 1 which sinks below the water surface. The first cooling water supply passage 33 is a passage that connects the water intake port 32 and the engine cooling mechanism 35 and allows the cooling water taken in through the water intake port 32 to flow toward the engine cooling mechanism 35. The water pump 34 is a pump configured to send the cooling water, which flows into the first cooling water supply passage 33 from the outside of the ship propulsion machine 1 through the water intake port 32, toward the engine cooling mechanism 35. The engine cooling mechanism 35 is, for example, a cooling jacket or a water jacket, and is implemented by a cooling passage formed inside or around the engine 4. The first cooling water discharge passage 36 is a passage that connects the engine cooling mechanism 35 and the water discharge port 37 and allows the cooling water flowed through the engine cooling mechanism 35 to flow toward the water discharge port 37. The water discharge port 37 is a port through which the cooling water flowed through the engine cooling mechanism 35 and the cooling water flowed through the heat exchanger 43 are discharged to the outside of the ship propulsion machine 1. The cooling water temperature control valve 38 is a valve for controlling a flow rate of the cooling water in the first cooling water supply passage 33 based on a temperature of the cooling water flowed through the engine cooling mechanism 35. The cooling water temperature control valve 38 is configured to control the flow rate of the cooling water in the first cooling water supply passage 33 so that the flow rate of the cooling water in the first cooling water supply passage 33 increases as the temperature of the cooling water flowed through the engine cooling mechanism 35 increases. The cooling water temperature control valve 38 is, for example, a thermostat.

The cooling structure 31 further includes a cooling medium circulation passage 39, a cooling medium pump 40, a motor cooling mechanism 41, an inverter cooling mechanism 42, the heat exchanger 43, and a degassing tank 44.

The cooling medium circulation passage 39 is a passage for circulating a cooling medium such as a coolant liquid among the motor cooling mechanism 41 and the inverter cooling mechanism 42 and the heat exchanger 43. The cooling medium pump 40 is a pump for circulating the cooling medium. The motor cooling mechanism 41 is, for example, a cooling jacket, and is implemented by a cooling passage formed inside or around the motor 17. The motor cooling mechanism 41 is connected to the cooling medium circulation passage 39. The inverter cooling mechanism 42 is, for example, a cooling jacket, and is implemented by a cooling passage formed inside or around the inverter 19. The inverter cooling mechanism 42 is connected to the cooling medium circulation passage 39. The heat exchanger 43 is a device for cooling the cooling medium circulating in the cooling medium circulation passage 39 by exchanging heat between the cooling medium circulating in the cooling medium circulation passage 39 and the cooling water taken in through the water intake port 32. The heat exchanger 43 has a cooling medium flow path and a cooling water flow path. The cooling medium flow path is connected to the cooling medium circulation passage 39. The cooling water flow path is connected to the first cooling water supply passage 33 via a second cooling water supply passage 45 branched from the first cooling water supply passage 33. The degassing tank 44 has a function of separating a gas in the cooling medium circulating in the cooling medium circulation passage 39 from the cooling medium, and is connected to the cooling medium circulation passage 39.

The cooling structure 31 further includes the second cooling water supply passage 45, a second cooling water discharge passage 46, and an inflow control valve 47.

The second cooling water supply passage 45 branches from the first cooling water supply passage 33 and connects the first cooling water supply passage 33 and the cooling water flow path of the heat exchanger 43. The second cooling water discharge passage 46 is a passage connecting the cooling water flow path of the heat exchanger 43 and the water discharge port 37. The inflow control valve 47 is a valve for controlling the inflow of the cooling water from the first cooling water supply passage 33 to the second cooling water supply passage 45. Specifically, the inflow control valve 47 is configured to control the amount of the cooling water flowing into the second cooling water supply passage 45 from the first cooling water supply passage 33 such that the amount of the cooling water flowing into the second cooling water supply passage 45 from the first cooling water supply passage 33 decreases as the pressure of the cooling water in the first cooling water supply passage 33 increases.

In a case where the ship propulsion machine 1 is operated, the rotation of the engine 4 or the motor 17 is transmitted to the transmission shaft 23, and the transmission shaft 23 rotates. For example, the water pump 34 is driven by receiving the rotation of the transmission shaft 23. The cooling medium pump 40 is, for example, an electric pump (a pump that includes a pump driving motor for pump driving and is driven by the pump driving motor). During the operation of the ship propulsion machine 1, electric power is supplied to the pump driving motor of the cooling medium pump 40, and the cooling medium pump 40 is driven.

The water outside the ship propulsion machine 1 flows into the first cooling water supply passage 33 via the water intake port 32 as the cooling water based on the driving of the water pump 34, sequentially flows through the first cooling water supply passage 33, the engine cooling mechanism 35, and the first cooling water discharge passage 36, and then is discharged from the water discharge port 37 to the outside of the ship propulsion machine 1. In this process, the engine 4 is cooled by the cooling water flowing through the engine cooling mechanism 35.

The cooling medium circulates in the cooling medium circulation passage 39 by driving the cooling medium pump 40. Accordingly, the cooling medium sequentially flows through the motor cooling mechanism 41, the inverter cooling mechanism 42, and the cooling medium flow path of the heat exchanger 43. The motor 17 is cooled by the cooling medium flowing through the motor cooling mechanism 41. The inverter 19 is cooled by the cooling medium flowing through the inverter cooling mechanism 42.

A part of the cooling water flowing through the first cooling water supply passage 33 flows through the second cooling water supply passage 45, the cooling water flow path of the heat exchanger 43, and the second cooling water discharge passage 46 based on the driving of the water pump 34, and then is discharged from the water discharge port 37 to the outside of the ship propulsion machine 1. In this process, the cooling medium flowing through the cooling medium flow path of the heat exchanger 43 is cooled by the cooling water flowing through the cooling water flow path of the heat exchanger 43.

(Attachment Structure of Motor and Inverter)

FIG. 5 is a diagram illustrating a part of the engine 4, the motor 17, the inverter 19, the heat exchanger 43, an inverter bracket 61, and the like in the ship propulsion machine 1 illustrated in FIG. 1 as viewed from the left. FIG. 6 illustrates the motor 17, the inverter 19, the heat exchanger 43, the inverter bracket 61, and the like illustrated in FIG. 5 as viewed from the rear. FIG. 7 illustrates the part of the engine 4, the motor 17, the inverter 19, the heat exchanger 43, the inverter bracket 61, and the like which are separated from each other.

As illustrated in FIG. 7, two inverter bracket attachment portions 51 and 52 are provided on a left portion of the rear portion of the oil pan 15 of the engine 4. One inverter bracket attachment portion 51 is arranged at a middle portion in the upper-lower direction of the left portion of the rear portion of the oil pan 15. The other inverter bracket attachment portion 52 is arranged on a lower portion of the left portion of the rear portion of the oil pan 15. Although not illustrated, two inverter bracket attachment portions are provided on a right portion of the rear portion of the oil pan 15, and the respective two inverter bracket attaching portions are arranged at a middle portion in the upper-lower direction of the right portion of the rear portion of the oil pan 15 and at a lower portion of the right portion of the rear portion of the oil pan 15. A motor attachment portion 54 is provided at the left portion of the rear portion of the oil pan 15 of the engine 4. Although not illustrated, a motor attachment portion is also provided at the right portion of the rear portion of the oil pan 15 of the engine 4. The recessed portion 16 recessed upward is provided at the rear portion of the lower surface of the oil pan 15 of the engine 4 (see also FIG. 3).

The ship propulsion machine 1 is provided with a base 20 configured to support the engine 4 and the motor 17 (see also FIG. 1). A motor attachment portion 55 is provided on a left portion of a rear portion of the base 20. Although not illustrated, a motor attachment portion is also provided on a right portion of the rear portion of the base 20.

As illustrated in FIGS. 6 and 7, four coupling protrusions 56 for attaching the motor 17 to the motor attachment portions 54 and 55 are provided on an outer peripheral surface of a motor case of the motor 17. An inverter bracket attachment portion 53 is provided at a left portion of an upper portion of the motor case of the motor 17. Although not illustrated, an inverter bracket attachment portion is also provided on a right portion of the upper portion of the motor case of the motor 17.

As illustrated in FIG. 5, the motor 17 is arranged below the rear portion 5A of the engine body 5. The motor 17 is positioned behind the base 20. The upper portion of the front portion of the motor 17 is inserted into the recessed portion 16 provided in the lower surface of the oil pan 15. The motor 17 is attached to and fixed to the engine 4 and the base 20 by respectively coupling four coupling protrusions 56 provided on the motor 17 to the two left and right motor attachment portions 54 provided on the oil pan 15 and the two left and right motor attachment portions 55 provided on the base 20 using a coupling member such as a bolt.

The inverter 19 and the heat exchanger 43 are attached to the inverter bracket 61. The inverter bracket 61 to which the inverter 19 and the heat exchanger 43 are attached is arranged behind the oil pan 15 and between the rear portion 5A of the engine body 5 and the motor 17. The inverter bracket 61 is attached to and fixed to the engine 4 (oil pan 15) and the motor 17 by respectively coupling later-described coupling portions 71, 72, and 73 provided on the inverter bracket 61, using a coupling member such as a bolt, to the two left and right inverter bracket attachment portions 51 provided on the oil pan 15, the two left and right inverter bracket attachment portions 52 provided on the oil pan 15, and the two left and right inverter bracket attachment portions 53 provided on the motor 17. When the inverter bracket 61 to which the inverter 19 and the heat exchanger 43 are attached is attached to the engine 4 and the motor 17, the inverter 19 is arranged behind the oil pan 15 and between the rear portion 5A of the engine body 5 and the motor 17, and the heat exchanger 43 is arranged behind the oil pan 15 and between the rear portion 5A of the engine body 5 and the inverter 19.

(Inverter Bracket)

FIG. 8A illustrates the inverter bracket 61 as viewed from the left. FIG. 8B illustrates the inverter bracket 61 as viewed from above. FIG. 8C illustrates the inverter bracket 61 as viewed from the front. FIG. 9A illustrates the inverter bracket 61 with the inverter 19 attached, as viewed from the left. FIG. 9B illustrates a cross-sectional view of the inverter bracket 61 and the inverter 19 cut along a cutting line IXb-IXb in FIG. 9A, as viewed from the front (which is the left side in FIG. 9A).

The inverter bracket 61 is a member for attaching the inverter 19 and the heat exchanger 43 to the engine 4 and the motor 17. As illustrated in FIGS. 8A and 8B, the inverter bracket 61 includes an inverter fixing portion 62, two leg portions 66, two arm portions 67, and four bosses 68. The inverter fixing portion 62, the leg portion 66, the arm portion 67, and the boss 68 are made of a material having high strength such as metal.

The inverter fixing portion 62 is a portion for fixing the inverter 19 to the inverter bracket 61. The inverter fixing portion 62 includes a left support portion 63 configured to support a left portion of the inverter 19 from a left side of the inverter 19, a right support portion 64 configured to support a right portion of the inverter 19 from a right side of the inverter 19, and a rear support portion 65 configured to support a rear portion of the inverter 19 from a rear side of the inverter 19. As illustrated in FIG. 8B, when the inverter fixing portion 62 is viewed from above, the inverter fixing portion 62 is formed in a U-shape as a whole. As illustrated in FIGS. 9A and 9B, the inverter 19 is arranged inside the inverter fixing portion 62.

An annular support member 69 is attached to an inner peripheral side of the inverter fixing portion 62. The annular support member 69 is formed into an annular shape from, for example, a resin or a hard rubber. As illustrated in FIG. 9B, in a case where the inverter 19 is arranged inside the inverter fixing portion 62, the annular support member 69 is arranged between the inverter fixing portion 62 and the inverter 19. The inverter 19 is supported on the inverter fixing portion 62 via the annular support member 69. The annular support member 69 has a function of supporting the inverter 19 on the inverter fixing portion 62, a function of preventing transmission of vibration from the engine 4 and the motor 17 to the inverter 19, and a function of preventing heat conduction from the engine 4 and the motor 17 to the inverter 19.

The leg portion 66 has a function of connecting the inverter fixing portion 62 to the engine 4 and the inverter fixing portion 62 to the motor 17. As illustrated in FIGS. 8A to 8C, of the two leg portions 66, one leg portion 66 extends downward from a left portion of the inverter fixing portion 62, specifically, from the left support portion 63. The other leg portion 66 extends downward from a right portion of the inverter fixing portion 62, specifically, from the right support portion 64.

The arm portion 67 has a function of connecting the inverter fixing portion 62 to the engine 4. Of the two arm portions 67, one arm portion 67 extends forward from a left front portion of the inverter fixing portion 62, specifically, from a front end portion of the left support portion 63 (strictly speaking, from a front end portion of an upper end portion that is coupled to the left support portion 63 at the left leg portion 66). The other arm portion 67 extends forward from a right front portion of the inverter fixing portion 62, specifically, from a front end portion of the right support portion 64 (strictly speaking, from a front end portion of an upper end portion that is coupled to the right support portion 64 at the right leg portion 66).

The coupling portion 71 for attaching the inverter bracket 61 to the inverter bracket attachment portion 51 provided in the oil pan 15 is provided at a front end portion of each arm portion 67. The coupling portion 72 for attaching the inverter bracket 61 to the inverter bracket attachment portion 52 provided in the oil pan 15 is provided at a front portion of a lower end portion of each leg portion 66. The coupling portion 73 for attaching the inverter bracket 61 to the inverter bracket attachment portion 53 provided in the motor 17 is provided at a lower end portion of each leg portion 66 and is further rearward than the coupling portion 72.

The boss 68 has a function of attaching the heat exchanger 43 to the inverter bracket 61. Of the four bosses 68, two bosses 68 protrude upward from an upper surface of the left support portion 63 of the inverter fixing portion 62. The remaining two bosses 68 protrude upward from an upper surface of the right support portion 64 of the inverter fixing portion 62. As illustrated in FIGS. 5 and 6, the heat exchanger 43 is attached to and fixed to the four bosses 68 via two heat exchanger brackets 75. That is, a left portion of the heat exchanger 43 is fixed to the two bosses 68 provided on the left support portion 63 via one heat exchanger bracket 75, and a right portion of the heat exchanger 43 is fixed to the two bosses 68 provided on the right support portion 64 via the other heat exchanger bracket 75. Since the heat exchanger 43 is attached to the inverter bracket 61 in this way, the heat exchanger 43 is arranged above the inverter 19 so as not to contact the inverter 19.

In the ship propulsion machine 1 according to the embodiment of the present disclosure described above, as illustrated in FIG. 2, by arranging the engine 4 vertically such that the extension direction of the rotation axis of the crank shaft 6 is in the upper-lower direction, and arranging the engine drive shaft 21 such that the engine drive shaft 21 extends in the upper-lower direction in front of the oil pan 15 of the engine 4, the engine drive shaft 21 can be arranged along the front surface of the oil pan 15 and can be brought close to the front surface of the oil pan 15.

Further, by arranging the motor 17 below the rear portion 5A of the engine body 5 such that the extension direction of the output shaft 18 is in the front-rear direction and the position of the output shaft 18 is further downward than the oil pan 15 of the engine 4, and arranging motor drive shaft 22 such that the motor drive shaft 22 extends in the front-rear direction below the oil pan 15, the motor drive shaft 22 can be arranged along the lower surface of the oil pan 15 and can be brought close to the lower surface of the oil pan 15.

Further, by arranging the power switching mechanism 24 below the lower end of the engine drive shaft 21 and in front of the front end of the motor drive shaft 22, the power switching mechanism 24 can be arranged close to the front lower corner of the oil pan 15 of the engine 4.

Further, the oil pan 15 extends downward from the front portion of the engine body 5 or the middle portion in the front-rear direction in a state in which the engine 4 is arranged vertically, and thus in the state in which the engine 4 is arranged vertically, the rear surface of the rear portion 5A of the engine body 5 is positioned further rearward than the rear surface of the oil pan 15. That is, the rear portion 5A of the engine body 5 protrudes further rearward than the oil pan 15. Therefore, when the motor 17 is arranged below the rear portion 5A of the engine body 5, a space is formed behind the oil pan 15 and between the rear portion 5A of the engine body 5 and the motor 17. By arranging the inverter 19 behind the oil pan 15 and between the rear portion 5A of the engine body 5 and the motor 17, that is, by arranging the inverter 19 in the space, the inverter 19 can be brought close to the oil pan 15, the rear portion 5A of the engine body 5, and the motor 17, respectively.

As described above, in the ship propulsion machine 1 according to the present embodiment, the engine drive shaft 21 can be arranged along the front surface of the oil pan 15 and can be brought close to the front surface of the oil pan 15, the motor drive shaft 22 can be arranged along the lower surface of the oil pan 15 and can be brought close to the lower surface of the oil pan 15, the power switching mechanism 24 can be arranged close to the front lower corner of the oil pan 15, and the inverter 19 can be brought close to the oil pan 15, the rear portion 5A of the engine body 5, and the motor 17, respectively. That is, according to the ship propulsion machine 1 of the present embodiment, the engine 4, the motor 17, the inverter 19, the engine drive shaft 21, the motor drive shaft 22, and the power switching mechanism 24 can be arranged in a compact manner with minimal gaps between each component. Accordingly, it is possible to reduce the size of the hybrid type ship propulsion machine 1.

Further, in the ship propulsion machine 1 according to the present embodiment, by arranging the heat exchanger 43 behind the oil pan 15 and between the rear portion 5A of the engine body 5 and the inverter 19, the heat exchanger 43 can be brought close to the oil pan 15, the rear portion 5A of the engine body 5, and the inverter 19, respectively. Therefore, according to the ship propulsion machine 1 of the present embodiment, it is possible to reduce the size of the hybrid type ship propulsion machine 1 including the heat exchanger 43.

In the ship propulsion machine 1 according to the present embodiment, the recessed portion 16 recessed upward is provided in the rear portion of the lower surface of the oil pan 15, and the upper portion of the front portion of the motor 17 is arranged in the recessed portion 16. Accordingly, in the ship propulsion machine 1, when the position of the engine 4 is used as a reference, the motor 17 can be arranged upward by the depth dimension of the recessed portion 16. Therefore, the vertical dimension of the ship propulsion machine 1 can be shortened, and the size of the ship propulsion machine 1 can be reduced.

The ship propulsion machine 1 according to the present embodiment further includes the inverter bracket 61, the inverter bracket 61 includes the inverter fixing portion 62 configured to fix the inverter 19 to the inverter bracket 61, the leg portion 66 extending downward from the inverter fixing portion 62, and the arm portion 67 extending forward from the inverter fixing portion 62 or the leg portion 66, and the inverter bracket 61 is supported on each of the engine 4 and the motor 17 by the leg portion 66 being connected to the engine 4 and the motor 17 and the arm portion 67 being connected to the engine 4. In this way, by supporting the inverter bracket 61 on both the engine 4 and the motor 17, the support strength and support stability of the inverter 19 and the heat exchanger 43 attached to the inverter bracket 61 can be increased. Further, by supporting the inverter bracket 61 on the motor 17 which is formed in a cylindrical shape and therefore has high rigidity, the supporting strength and supporting stability of the inverter 19 and the heat exchanger 43 can be increased.

In the ship propulsion machine 1 according to the present embodiment, the inverter fixing portion 62 of the inverter bracket 61 includes the left support portion 63 configured to support the left portion of the inverter 19 from the left side of the inverter 19, the right support portion 64 configured to support the right portion of the inverter 19 from the right side of the inverter 19, and the rear support portion 65 configured to support the rear portion of the inverter 19 from the rear side of the inverter 19. According to this configuration, the inverter 19 can be supported so as to be surrounded by the inverter fixing portion 62, so that the inverter 19 and the inverter fixing portion 62 can be integrated together. Therefore, the inverter 19 can be firmly fixed to the inverter bracket 61. By configuring the inverter fixing portion 62 to surround the inverter 19 from the left, right, and rear, the inverter 19 can be brought closer to the motor 17 by at least the thickness of the plate-shaped inverter fixing portion as compared with a case in which the inverter 19 is placed on the upper surface of the plate-shaped inverter fixing portion. Further, by configuring the inverter fixing portion 62 to surround the inverter 19 from the left, right, and rear, the leg portion 66 can be made shorter as compared with a case in which the inverter 19 is attached to a lower surface of the plate-shaped inverter fixing portion, thereby increasing the support strength and support stability of the inverter 19.

In the ship propulsion machine 1 according to the present embodiment, the boss 68 protruding upward is provided on the inverter fixing portion 62, and the heat exchanger 43 is fixed to the boss 68. This allows the inverter 19 and the heat exchanger 43 to be attached to the engine 4 and the motor 17 by means of a single inverter bracket 61. Therefore, the number of parts required to attach the inverter 19 and the heat exchanger 43 to the engine 4 and the motor 17 can be reduced, and the installation work for attaching the inverter 19 and the heat exchanger 43 to the engine 4 and the motor 17 can be simplified.

The present disclosure can also be applied to a ship propulsion machine that does not include the heat exchanger 43. The present disclosure can also be applied to other types of ship propulsion machines other than the outboard motor.

The foregoing description of the exemplary embodiments of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to understand the invention for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents.