JPH0767917B2 - Ship propulsion - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a marine propulsion device such as an outboard motor.

[Prior Art] Conventionally, as described in Japanese Utility Model Publication No. 54-10411, as a ship propulsion device, "an engine is mounted on an upper portion of a propulsion casing, and a drive shaft connected to the engine and an exhaust passage of the engine are communicated with each other. The exhaust pipe is housed in the propulsion casing, the exhaust pipe is directly connected to the engine, the propulsion casing is directly connected around the exhaust outlet of the engine, and an exhaust expansion chamber communicating with the exhaust pipe is formed in the propulsion casing. There are things. According to this, by directly connecting the engine and the propulsion casing provided with the exhaust expansion chamber, the two are connected by a structure only through a single sealing material, and from the connecting portion between the engine and the propulsion casing. Exhaust gas leakage can be reliably and easily prevented.

Further, in a ship propulsion device, generally, as described in JP-A-59-230897, the upper part of the steering shaft is supported by the upper mount part on the upper end part of the steering shaft, and the lower end part of the steering shaft is supported. The lower part of the propulsion casing is supported by the lower mount part on the above-mentioned part.

[Problems to be Solved by the Invention] However, in the conventional techniques as described above,
There is a problem.

When the propulsion casing is directly connected around the exhaust outlet of the engine, the length that the mount rubber makes with respect to the crank axis of the engine is made small, so that even if the spring constant of the mount rubber is made large, the natural vibration of the entire system is reduced. In order to make it small, it is necessary to dispose the mount rubber of the upper mount portion in the recess provided on the side surface of the propulsion casing, which complicates the structure for supporting the upper mount portion.

The left and right mount housings for fixing the pair of left and right mount rubbers forming the upper mount portion are separate bodies, and the distance between the pair of mount rubbers is relatively large. Therefore,
There is a limit to narrowing the left and right width of the propulsion casing,
It is difficult to reduce propulsion resistance.

Since each of the pair of left and right mount rubbers is fixed to the propulsion casing side via the left and right separate mount housings, the assembly of the mount portion is complicated.

The present invention simplifies the structure for supporting the upper mount portion when directly connecting the propulsion casing around the exhaust outlet of the engine, and reduces the lateral width of the propulsion casing to reduce propulsion resistance. The purpose is to facilitate the assembly of the mount portion.

[Means for Solving the Problems] The present invention mounts an engine on the upper part of a propulsion casing,
An insertion chamber through which the drive shaft connected to the engine penetrates is formed in the propulsion casing, an exhaust pipe communicating with the exhaust passage of the engine is housed in the propulsion casing, and the exhaust pipe is directly connected to the engine and the propulsion casing is An exhaust expansion chamber communicating directly with the exhaust pipe of the engine and the exhaust pipe is formed in the propulsion casing.The upper end of the steering shaft supports the upper part of the propulsion casing through the upper mount, and the lower end of the steering shaft. In a marine vessel propulsion device in which the lower part of the propulsion casing is supported by a lower mount part, a notch is formed in the upper front part of the propulsion casing to form an upper opening facing the lower surface of the engine with a gap. The drive shaft through the insertion chamber, and direct it from the rear side of this opening in the propulsion casing to the underside of the engine. A front wall that rises and partitions the inside and outside of the propulsion casing is formed on the propulsion casing, and is fixed to the propulsion casing so as to close the front wall and the opening below the engine on the upper front part of the propulsion casing. A recess formed with the lid is provided, and a pair of left and right mount rubbers constituting the upper mount portion are arranged in the recess in the vicinity of each other in a substantially horizontal direction. It is adapted to be fixed to the lid body through the above.

[Operation] In connecting the propulsion casing directly around the exhaust outlet of the engine, "a recess for accommodating the upper mount part was formed in the upper front part of the propulsion casing by using the front wall that partitions the inside and outside of the propulsion casing." The structure for supporting the upper mount portion is simplified.

Also, because "a pair of left and right mount rubbers are arranged in the recess in the horizontal direction in close proximity to each other and both mount rubbers are fixed by a common mount housing", the gap between the pair of mount rubbers should be narrower. You can Therefore, the propulsion resistance can be reduced by narrowing the lateral width of the propulsion casing, and smooth navigation is possible.

Furthermore, since "both mount rubbers are fixed to the lid body through a common mount housing", these sub-assemblies can be easily performed, and the mount portion can be easily assembled.

[Embodiment] FIG. 1 is a side view showing an outboard motor according to an embodiment of the present invention partially broken away, and FIG. 2 is an end view taken along line II-II of FIG.
3 is a sectional view taken along the line III-III in FIG. 1, FIG. 4 is a sectional view taken along the line IV-IV in FIG. 1, and FIG. 5 is a side view showing the entire outboard motor.

As shown in FIGS. 1 and 5, the outboard motor 10 has a clamp bracket 11 attached to a hull 12 and is provided with a clamp bracket.
The swivel bracket 14 is tiltably supported by the tilt shaft 13 and the steering shaft 15 is supported by the swivel bracket 14.
Is rotatably supported.

The outboard motor 10 has a steering handlebar 16 fixed to an upper end portion of a steering shaft 15, supports an upper portion of a propulsion casing 18 via an upper mount portion 17 connected to the steering handlebar 16, and also supports a lower end portion of the steering shaft 15. The lower part of the propulsion casing 18 is supported by the lower mount part 19 on the above-mentioned part. The propulsion casing 18 has an engine 20 mounted on the upper part,
It has a propeller 21 driven by an engine 20. 22 is a drive shaft.

The upper mount portion 17 is a lower mount housing 23 (corresponding to the lid of the present invention) that closes the opening 18A of the propulsion casing 18 through which the drive shaft 22 penetrates, as shown in FIGS.
And an upper mount housing 24 attached to the lower mount housing 23. 23A is an insertion hole for the drive shaft 22 provided in the lower mount housing 23. Both mount housings 23, 24 are internally held in a state of sandwiching a pair of left and right mount rubbers 25, and are fixed to the propulsion casing 18 by bolts 26. Each mount rubber 25
A connecting pipe 27 connected to the steering handle 16 is joined to the central portion of the. An annular seal member 28 is inserted between the propulsion casing 18 and the lower mount housing 23. The seal member 28 is configured to reliably seal the opening 18A.

That is, in the outboard motor 10, the upper opening 18A that faces the lower surface of the engine 20 with a gap is formed in the upper front portion of the propulsion casing 18 by notching, and the drive shaft 22 is inserted through the upper opening 18A. While inserting into the insertion chamber 46B, the front wall 201 that stands up toward the lower surface side of the engine 20 from the rear side of the opening 18A in the propulsion casing 18 to partition the inside and outside of the propulsion casing 18 is formed in the propulsion casing 18, On the upper front side of the propulsion casing 18 below the engine,
201 and the propulsion casing so as to close the opening 18A.
A recess 202 formed with a lower mount housing 23 as a lid fixed to 18 is provided (FIG. 1), and a pair of left and right mount rubbers forming the upper mount 17 in the recess 202.
The two mount rubbers 25 are fixed to the lower mount housing 23, which is the lid, through a common upper mount housing 24.
Note that, in FIG. 1, the wall 203 rising up to the forefront of the propulsion casing 18 is not a front wall that partitions the inside and outside of the propulsion casing 18.

As shown in FIGS. 1 and 3, the lower mount portion 19 includes an upper mount housing 30A and a lower mount housing 30B which are vertically divided. Both mount housings 30A,
30B is fastened vertically by bolts 30C, and holds left and right mount rubbers 31 located on both sides of the propulsion casing 18 and a mount rubber 32 located on the front side of the propulsion casing 18. 33 is a mount rubber mounting portion of the propulsion casing 18. Reference numeral 34 is a rear positioning portion for the mount rubber 31 formed on the propulsion casing 18, and 35 is a front positioning member for the mount rubber 31 fixed to the propulsion casing 18.

Here, the left and right mount rubbers 25 of the upper mount 17
Is arranged inside the side surface 101 formed by connecting the side portion of the engine 20 and the side portion of the propulsion casing 18 (fourth portion).
Figure).

Thus, the outboard motor 10 arranges the exhaust pipe 37, which is directly connected to the exhaust passage 36 of the engine 20, inside the propulsion casing 18, and the propulsion casing 18 directly around the exhaust outlet of the engine 20. The propulsion casing 18 and the engine 20 are connected to each other, and the seal member 20A is arranged at the above-mentioned connecting portion.

Further, the outboard motor 10 includes a water pump 38 driven by the drive shaft 22 inside the propulsion casing 18, and the water pump 38
The outside water to be sucked and pumped by is supplied to the water jacket of the engine 20 to cool the engine 20 with water. A drain passage 40 communicating with a drain passage 39 of the engine 20 is formed at the upper end of the exhaust pipe 37.

The propulsion casing 18 includes a partition wall 41 in front of the exhaust pipe 37.

The outboard motor 10 has a water jacket 43 surrounding the entire circumference of the exhaust pipe 37 between the exhaust pipe 37 and the partition wall 41 of the propulsion casing 18 and the outer peripheral wall 42A on the rear side. 44 is a water jacket 43
A seal member mounted between the propulsion casing 18 and the exhaust pipe 37 located at the bottom of the. Reference numeral 45 is a drain passage provided in the exhaust pipe 37 for draining overflow water of the water jacket 43.

The outboard motor 10 includes the partition wall 41 and the partition wall of the propulsion casing 18.
Another partition wall 41B disposed on the front side of 41 forms an exhaust expansion chamber 46 that is located in front of the location where the exhaust pipe 37 is disposed. A part of the partition wall 41B surrounds the drive shaft 22 with the outer peripheral wall 42B, and the drive shaft 22 insertion chamber 46B.
To form. The upper opening of the drive shaft insertion chamber 46B is included in the opening 18A of the propulsion casing 18 described above. The drive shaft 22 is inserted into the insertion chamber 46B of the propulsion casing 18 through the opening 23A provided in the lower mount housing 23. A seal member 29 is arranged at the upper end of the partition wall 41B so that the exhaust gas in the expansion chamber 46 can be separated from the lower mount housing 23 and the partition wall 41B.
It is prevented from leaking to the insertion chamber 46B through the gap between the upper end and the upper mount portion 17 and further through the opening 23A. The seal member 20A prevents the exhaust gas in the expansion chamber 46 from leaking out from the connecting portion between the propulsion casing 18 and the engine 20. The exhaust expansion chamber 46 communicates with the outside through an exhaust passage 47 formed in a lower portion of the propulsion casing 18 and an exhaust passage formed in a boss portion of the propeller 21. The propulsion casing 18 has an exhaust communication passage 48 opened in an upper portion of the partition wall 41. This allows the exhaust expansion chamber 46
Communicates with the upper space of the water jacket 43 through the exhaust communication passage 48, and further communicates with the outside through an idle port 49 provided in the outer peripheral wall 42A on the rear side of the propulsion casing 18. That is, in the low-speed low-load operating range of the engine 20, the exhaust pressure reaching the exhaust expansion chamber 46 is lower than the head pressure of the external water acting on the exhaust passage 46, so the exhaust gas is exhausted from the exhaust expansion chamber 46 and the exhaust communication passage. 48, through the space above the water jacket 43 and discharged from the idle port 49. On the other hand, the engine
In the high-speed, high-load operation region of 20, the exhaust pressure reaching the exhaust expansion chamber 46 becomes large due to the head pressure of the external water acting on the exhaust passage 46, and the exhaust gas passes through the exhaust expansion chamber 46 and the exhaust passage 47 to reach the propeller 21. It is discharged from the boss. The idle port 49 is opened at the left rear portion or right side rear portion (in this embodiment, right side rear portion) of the propulsion casing 18.

The outboard motor 10 is provided with drainage holes 50 communicating with the bottom portion of the water jacket 43 at portions on both sides of the propulsion casing 18 which are close to the rear positioning portion 34 for the mount rubber 31.

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

According to the above embodiment, the mount rubber of the upper mount portion 17
Since the 25 is arranged inside the side surface 101 formed by connecting the side portion of the engine 20 and the side portion of the propulsion casing 18, the length formed by the mount rubber 25 with respect to the crank axis of the engine 20 is small. Therefore, even if the spring constant of the mount rubber 25 is increased, the natural vibration of the entire system can be reduced. Therefore, it is possible to endure a high propeller thrust under the condition that the vibration of the propulsion casing 18, the engine 20, etc. is suppressed to a low level.

Further, according to the above embodiment, the engine 20 and the exhaust expansion chamber
Propulsion casing 18 with 46 and a single sealing member 20A
Therefore, the exhaust leakage from the connecting portion between the engine 20 and the propulsion casing 18 can be prevented more reliably and easily.

In addition, according to the above-described embodiment, when directly connecting the propulsion casing 18 around the exhaust outlet of the engine 20, “using the front wall 201 that partitions the inside and outside of the propulsion casing 18, the upper front portion of the propulsion casing 18 is provided. Since the concave portion 202 for housing the mount portion 17 is formed ", the structure for supporting the upper mount portion 17 becomes simple.

In addition, according to the above-mentioned embodiment, “a pair of left and right mount rubbers 25 are arranged in the recess 202 in proximity to each other in a substantially horizontal direction, and both mount rubbers 25 are fixed by a common upper mount housing 24”. Therefore, the distance between the pair of mount rubbers 25 can be further narrowed. Therefore,
By reducing the lateral width of the propulsion casing 18, propulsion resistance is reduced and smooth navigation is possible.

Further, according to the above-mentioned embodiment, "the both mount rubbers 25
Is fixed to the lower mount housing 23, which is the lid of the present invention, via the common upper mount housing 24. ”Therefore, these sub-assemblies can be easily performed, and the assembly of the mount portion can be facilitated.

As described above, according to the present invention, when the propulsion casing is directly connected around the exhaust outlet of the engine, the structure for supporting the upper mount portion is simplified and the lateral width of the propulsion casing is reduced. By making it narrower, the propulsion resistance can be reduced and the assembly of the mount portion can be facilitated.

[Brief description of drawings]

FIG. 1 is a side view showing an outboard motor according to an embodiment of the present invention partially broken away, and FIG. 2 is an end view taken along line II-II of FIG.
3 is a sectional view taken along the line III-III in FIG. 1, FIG. 4 is a sectional view taken along the line IV-IV in FIG. 1, and FIG. 5 is a side view showing the entire outboard motor. 10 …… Outboard motor, 15 …… Steering shaft, 17 …… Upper mount, 18 …… Propulsion casing, 19 …… Lower mount, 20
…… Engine, 20A …… Seal member, 23 …… Lower mount housing (lid), 24 …… Upper mount housing (common mount housing), 25 …… Mount rubber, 36
...... Exhaust passage, 37 ...... Exhaust pipe, 46 ...... Exhaust expansion chamber, 201
…… Front wall, 202 …… Concave.

Claims (1)

[Claims] 1. An engine mounted on an upper part of a propulsion casing, an insertion chamber through which a drive shaft connected to the engine penetrates is formed in the propulsion casing, and an exhaust pipe communicating with an exhaust passage of the engine is housed in the propulsion casing. The exhaust pipe is directly connected to the engine, the propulsion casing is directly connected around the exhaust outlet of the engine, the exhaust expansion chamber communicating with the exhaust pipe is formed in the propulsion casing, and the upper mount part is attached to the upper end of the steering shaft. In a marine vessel propulsion system that supports the upper part of the propulsion casing via the lower part of the steering shaft via the lower mount part on the lower end of the steering shaft, the upper opening facing the lower surface of the engine with a gap. A notch is formed in the upper front part of the propulsion casing, the drive shaft is inserted into the insertion chamber through this upper opening, and the propulsion casing A front wall that rises from the rear side of this opening toward the lower surface side of the engine to partition the inside and outside of the propulsion casing is formed in the propulsion casing. A recess formed with a lid body fixed to the propulsion casing so as to close the opening, and a pair of left and right mount rubbers constituting an upper mount portion are provided in the recess in a substantially horizontal direction. A marine vessel propulsion device, which is provided with both mount rubbers fixed to the lid through a common mount housing.