JP3405472B2 - Outboard motor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outboard motor having a steering shaft connected to an upper casing via an upper mount portion and a lower mount portion.

[0002]

2. Description of the Related Art Generally, in an outboard motor, a steering shaft is steerably supported by a swivel bracket on the hull side.
An upper casing, on which an engine is mounted and which forms an outboard motor body, is elastically supported on the steering shaft via an upper mount portion and a lower mount portion. The upper mount part divides a steering bracket to which a steering handle is connected into left and right parts, and the upper and lower parts of a steering shaft having a substantially circular cross section are sandwiched between these two half parts, and the left and right half parts and the steering shaft are separated from each other. It is configured such that the steering bracket is joined in a state of being stopped by a bolt, and the rear portion of the steering bracket is connected to a mount member above the upper casing via an elastic material.

Further, the lower mount portion has a structure in which the steering shaft and the lower portion of the upper casing are sandwiched between a pair of left and right lower mount housings to connect them. Then, the upper casing is elastically supported on the steering shaft by interposing an elastic material between the left and right lower mount housings and the upper casing. To prevent the lower mount housing from rotating with respect to the steering shaft at the lower mount portion, the lower end portion of the steering shaft is formed to have a substantially square cross section, and the steering shaft holding portion of the lower mount housing is fitted to the square portion. It was done by forming into a different shape.

[0004]

However, if the upper mount portion and the lower mount portion are formed as described above, there is a problem that the cost becomes high, and it is difficult to make the steering shaft thin and reduce the weight. There was a problem. The reason for the high cost is that in the upper mount part, holes for the coupling bolts must be machined in both the steering bracket and the steering shaft, which increases the number of manufacturing steps. Further, the fact that the number of parts and the number of assembling steps are increased due to the connection of the two by bolts also causes a cost increase.

On the other hand, in the lower mount part, when the lower end of the steering shaft has a square shape, the shaft diameter above it must be a circumscribing circle with a square shape, and thus the shaft diameter must be increased. . The thicker the steering shaft, the heavier the weight.

The present invention has been made in order to solve such a problem, and reduces the machining to be performed on the upper mount portion and the lower mount portion as much as possible and reduces the number of parts in the upper mount portion. The purpose is to reduce costs. Another object of the present invention is to make it possible to secure a coupling force while avoiding a thickening of the steering shaft in the lower mount portion.

[0007]

According to a first aspect of the present invention, an outboard motor has a lower mount portion in which a lower end portion of a steering shaft is held by a pair of left and right lower mount housings extending forward from the upper casing side. The steer
For the ring shaft, use a mold whose mold splitting direction is the outboard motor left / right direction.
It is formed into a circular cross section by the casting used and the lower end
Through hole is formed in the part, and the lower mount housing
The steering shaft holding portion is fitted with the steering shaft.
Pin shaped into a shape and fitted into the through hole
Is integrally projected, and the pin is fitted into the through hole.
Position above and below the steering shaft.
The front connecting bolt and the steering shaft
With the rear connecting bolts that are located above and below
By fastening the lower mount housings together,
These lower mount housings allow the steer to
The steering shaft is held by pinching and holding the steering shaft.
On the other hand, the lower mount housing is not rotated.

An outboard motor according to a second aspect of the invention is
In the outboard motor according to the first aspect of the present invention, the steering bracket is cast by loading a steering shaft into a steering bracket molding die.

[0009]

According to the first aspect of the invention, the steering shaft can be assembled without any post-processing. Further, the coupling force between the steering shaft and the lower mount housing is ensured by fitting the pin into the pin hole.

According to the second aspect of the invention, since the steering bracket is formed in a state in which the steering shaft is integrated, the bolts for connecting the both are unnecessary and it is not necessary to open a bolt hole. Further, no special member is required to secure the coupling force between the steering bracket and the steering shaft.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIGS. 1 is a side view of an outboard motor according to the present invention, FIG. 2 is an enlarged sectional view of a main part of the outboard motor according to the present invention, and FIG. 3 is a line III-III of a steering bracket and a base plate in FIG. A sectional view, FIG. 4 is a sectional view taken along line IV-IV in FIG.

In these drawings, reference numeral 1 denotes an outboard motor according to the present invention. This outboard motor 1 has a two-cylinder two-cycle engine 3 mounted on an upper casing 2 and a lower casing 4 mounted on a lower portion. ing. 5 is the engine 3
It is a cowling that covers.

Reference numeral 6 denotes a clamp mechanism for attaching the outboard motor 1 to a hull (not shown), and a clamp bracket 7 fixed to the hull and a tilt shaft 8 attached to the clamp bracket 7.
Swivel bracket 9 swingably connected via
And an upper mount portion 1 pivotally supported by the swivel bracket 9 and connected to the upper casing 2.
0, a lower mount portion 11 and the like. Reference numeral 12 denotes a steering handle, which is attached to a steering bracket 13 of the upper mount portion 10 described later so as to be swingable back and forth. Note that FIG. 1 shows a non-cruising state in which the vehicle is tilted backward.

Reference numeral 14 denotes a propeller rotatably supported by a lower casing 4, and 15 denotes a propeller 14 for the engine 3
It is a drive shaft for transmitting the power of. The drive shaft 15 has an upper end coupled to a crankshaft (not shown) of the engine 3, extends vertically through the upper casing 2, extends into the lower casing 4 from above, and has a lower end portion connected to the propeller drive mechanism 14a. It is connected. Reference numeral 16 provided in the middle of the drive shaft 15 is an engine cooling water water pump.

The water pump 16 is a cooling water supply pipe 1 along which the water (for example, seawater) outside the outboard motor that has entered from the suction port 4a of the lower casing 4 is substantially along the drive shaft 15.
7 and the cooling water passage (not shown) at the upper opening edge of the upper casing 2 to supply the engine 3 from inside the lower casing 4.

The upper casing 2 is integrally formed of aluminum alloy, and the inside thereof is defined by a partition wall 18 in the front and back as shown in FIGS. 1 and 2.
In FIG. 2, the inner space of the upper casing on the front side is denoted by reference numeral 1
9, the inner space of the rear upper casing is indicated by reference numeral 20.
Indicate. An upper part of the front upper casing inner space 19 is closed by a base plate 21 which constitutes a part of the upper mount portion 10.

The base plate 21 is a cast product made of aluminum alloy and has a substantially flat seal plate portion 22 for closing the space 19 in the front upper casing.
And a holder portion 23 projecting upward from the seal plate portion 22 and connected to the rear end portion of the steering bracket 13 are integrally formed. As shown in FIG. 3, the seal plate portion 22 is formed in a substantially triangular shape with the rear side of the outboard motor as the bottom side in a plan view, and has screw holes 22a formed in the vicinity of the front portion and the left and right apexes. There is. The base plate 21 is fixed to the upper casing 2 by mounting bolts 24 through the screw holes 22 a and screwing the bolts into the upper casing 2. Also,
The seal plate portion 22 has a hole 22b through which the drive shaft 15 penetrates and a hole 22c through which the cooling water supply pipe 17 penetrates.
And have been drilled. These holes 22b and 22c are arranged substantially at the center of the seal plate 22 in the left-right direction.

As shown in FIG. 3, the holder portion 23 is constructed by arranging cylindrical bodies 23a on the left and right. A cushion rubber 26 is vulcanized and adhered to the hollow portion of the cylindrical body 23a with the collar 25 positioned at the axial center portion.
That is, by inserting the connecting bolt 27 into the collar 25 from the rear side and screwing the tip thereof to the steering bracket 13, the base plate 21 is connected to the steering bracket 13 via the cushion rubber 26 and elastically supported. Has become.

Further, the reference numeral 28 located on the rear surface side of the holder portion 23 is an elastic material.
Is configured such that when the propeller 14 rotates and a thrust force is generated, a thrust load is applied from a pressing plate 29 installed between the left and right connecting bolts 27.

A hole 22c for penetrating the cooling water supply pipe is formed between the left and right cylinders 23a.
A cooling water supply pipe 17 extends upward through the pipe. The cooling water supply pipe 17 penetrating the base plate 21 is bent between the base plate 21 and the engine 3, and is opened to a cooling water passage (not shown) formed by denting the upper portion of the upper casing 2 downward. . The cooling water passage is configured to communicate with a cooling water inlet (not shown) of the engine 3 with the engine 3 mounted on the upper casing 2. That is, the cooling water of the engine 3 enters the cooling water passage between the upper casing 2 and the engine 3 from the cooling water supply pipe 17, and is supplied into the engine 3 from here.

The steering bracket 13 is also an aluminum alloy casting, and extends forward from the connecting portion with the holder portion 23. As shown in FIGS. 2 and 3, the steering shaft 31 is connected in front of the upper casing 2. The steering handle 12 is connected to the front end of the steering wheel 12.

The steering shaft 31 is integrally formed by casting into a tubular shape having a circular cross section, and a through hole 31a as a pin hole according to the present invention is formed in the lower end portion thereof as shown in FIGS. ing. This steering shaft 3
In casting No. 1, the die for molding the outer peripheral portion of the die 1 is aligned with the lateral direction of the outboard motor so that the through hole 31a is simultaneously formed in the lower end portion during casting.

The steering bracket 13 made of a cast product is cast with the steering shaft 31 loaded in a steering bracket molding die (not shown). That is, the steering bracket 13 is cast by inserting the steering shaft 31. Therefore, when the steering shaft 31 is prevented from rotating with respect to the steering bracket 13, no special rotation preventing member is used.

The steering bracket 13 to which the steering shaft 31 is coupled in this way is
Is inserted into the tubular portion 9a of the swivel bracket 9 from above, and the tubular portion 9a has an upper end bearing 32 and a lower end bearing 33.
It is rotatably supported via.

When the steering shaft 31 is mounted on the swivel bracket 9 described above, the swivel bracket 9 is attached.
The lower mount portion 11 is coupled to the lower protruding portion. As shown in FIG. 2 and FIG. 4, the lower mount portion 11 holds the steering shaft 31 and the front portion of the upper casing 2 by a pair of left and right lower mount housings 34 and 35 to hold the upper casing 2 on the steering shaft 31. It has a structure to connect.

The lower mount housings 34, 35 are casted from an aluminum alloy, and cushion rubbers 36 are respectively interposed between the lower mount housings 34 and 35, and extend forward from the upper casing 2 so that their front end portions have a substantially sectional shape. It is formed so as to fit with the circular steering shaft 31. The cushion rubber 36 is fitted and retained in the recesses 2a, 34a, 35a of the upper casing 2 and the lower mount housings 34, 35.

Further, the lower mount housings 34, 35
The steering shaft holding part in the
Cylindrical pins 34b and 35b fitted in the through hole 31a
Are provided integrally. By fitting the pins 34b and 35b into the through hole 31a, the steering shaft 3
In order to prevent the lower mount housings 34, 35 from rotating with respect to 1, a dedicated positioning pin or the like is separately provided, or the steering shaft 31 or the lower mount housing 3
There is no need to machine detent fittings on 4, 35.

The left and right lower mount housings 3
4, 35 are fastened to each other by connecting bolts 37, 38 so as to hold the steering shaft 31 under pressure.
The connecting bolts 37 are arranged above and below the steering shaft 31, and the connecting bolts 38 are connected to the steering shaft 31.
They are arranged vertically above and behind.

That is, the lower mount portion 11 has the pin 3
Lower mount housing 3 fixed to the steering shaft 31 by fitting the 4b and 35b and the through hole 31a.
The upper casing 2 is elastically supported on the steering shaft 31 via the rubbers 4, 35 and the cushion rubber 36.

When the upper casing 2 is connected to the upper and lower sides of the steering shaft 13 via the upper mount portion 10 and the lower mount portion 11 as described above, the steering handle 12 connected to the steering bracket 13 is swung left and right. As a result, the upper casing 2 rotates about the steering shaft 31 with respect to the swivel bracket 9.

In FIG. 1, reference numeral 3 is provided in the upper case 2.
Reference numeral 9 indicates an exhaust pipe of the engine 3, and this exhaust pipe 39
Has an upper end fixed to the engine 3 and a lower end opening to the rear upper casing inner space 20 in the upper case 2. The rear upper casing inner space 20 communicates with a drainage / exhaust passage 4 b formed in the lower casing 4. The drainage / exhaust passage 4b communicates with the outside of the outboard motor via the propeller 14 and the shaft center of the propeller drive mechanism 14a.

In the outboard motor 1 constructed as described above, the steering force is applied to the steering bracket 13 and the lower mount portion 1 by swinging the steering handle 12 left and right.
1 is transmitted to the upper casing 2 and the outboard motor 1 is steered. At this time, the steering force applied to the steering bracket 13 is applied to the cushion rubber 26 and the base plate 2 from the steering bracket 13.
It is transmitted to the upper part of the upper casing 2 via 1 and is transmitted to the lower part of the upper casing 2 from the lower mount housings 34 and 35 via the cushion rubber 36.

Since the steering shaft 31 is inserted when the steering bracket 13 is cast as described above, the steering bracket 31 is formed in a state where the steering shaft 31 is integrated. When connecting in this state, bolts to be connected can be dispensed with, and there is no need to open a bolt hole or the like. Also, the steering bracket 1
No special member is required to secure the coupling force between the steering shaft 3 and the steering shaft 31.

Further, since the lower mount portion 11 is fitted with the lower mount housings 34, 35 having the pins 34b, 35b on the steering shaft 31 formed by casting in a substantially circular cross section and having the through hole 31a formed therein,
The rotation stop can be performed by the molded article itself.
Therefore, the steering shaft 31 can be assembled in the cast state without performing post-processing. Further, the coupling force between the steering shaft 31 and the lower mount housings 34, 35 is such that both are tightened by the four connecting bolts 37, 38, and the pins 34b, 35b have the through holes 3
It will be secured by fitting to 1a.

[0035]

[0036]

[0037]

As described above, in the outboard motor according to the first aspect of the invention, the lower mount portion has a structure in which the lower end portion of the steering shaft is held by a pair of left and right lower mount housings extending forward from the upper casing side. , The above
The tearing shaft is a metal whose split direction is the outboard motor left / right direction.
While being molded into a circular cross section by casting with a mold
The lower mount housing has a through hole formed at the lower end.
The steering shaft holding part of the
It is molded into a matching shape and fits into the through hole.
The pin is integrally projected, and the pin is inserted into the through hole.
With the steering shaft up and down,
The front connecting bolt located on the
Rear connecting bolts that are located vertically above and behind
Fasten the lower mount housings together.
The lower mount housing
By holding the aligning shaft under pressure, the stearin
Since the lower mount housing is prevented from rotating with respect to the shaft, the steering shaft can be assembled in the cast state without post-processing.

Therefore, it is not necessary to machine the lower end portion of the steering shaft and the steering shaft holding portion of the lower mount housing, so that the cost can be reduced. Moreover, since the coupling force between the steering shaft and the lower mount housing is secured by fitting the pin into the pin hole, it is possible to make the steering shaft thin enough to ensure rigidity, and to reduce the weight. be able to.

In the outboard motor according to the second aspect of the present invention, since the steering bracket is cast by loading the steering shaft in the steering bracket molding die, the steering bracket is formed with the steering shaft integrated. , The bolts for connecting the both are unnecessary and it is not necessary to open the bolt holes.

Therefore, no mechanical work is required to connect the steering shaft to the steering bracket, and the number of parts at the connecting portion can be minimized. In addition, no special member is needed to secure the coupling force between the steering bracket and the steering shaft. Furthermore, when a steering shaft formed by casting is used, the steering shaft can be firmly and inexpensively fixed to the steering bracket. This is because it is possible to join the entire area of the outer peripheral surface of the steering shaft to the steering bracket without making any special efforts.

Therefore, the structure of the upper mount portion can be simplified while securing the coupling force between the steering shaft and the steering bracket, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a side view of an outboard motor according to the present invention.

FIG. 2 is a cross-sectional view showing an enlarged main part of the outboard motor according to the present invention.

FIG. 3 is a sectional view taken along line III-III of the steering bracket and the base plate in FIG.

4 is a sectional view taken along line IV-IV in FIG.

[Explanation of symbols]

1 ... outboard motor, 2 ... upper casing, 3 ... engine,
10 ... Upper mount part, 11 ... Lower mount part, 1
3 ... Steering bracket, 21 ... Base plate,
31 ... Steering shaft, 31a ... Through hole, 34 ... Lower mount housing, 34b ... Pin, 35 ... Lower mount housing, 35b ... Pin.

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B63H 20/02 B63H 25/42

Claims (2)

(57) [Claims] The method according to claim 1] lower mount portion connecting the steering shaft to the upper casing engine is mounted, a structure for clamping the lower end of the steering shaft by the pair of right and left lower mount housing extending from the upper casing forward, the steering The axis is the direction of the ship
Circular cross section due to casting using a die that is lateral to the outer machine
And a through hole is formed at the lower end,
The steering shaft holding part of the lower mount housing is
In addition to being shaped to fit the steering shaft
A pin that fits into the through hole is integrally projected, and the pin
With the steering shaft fitted in the through hole,
Front connecting bolts located up and down more forward,
Rear up and down behind the steering shaft
The lower mount housing by the side connecting bolt
Let them fasten to each other and these lower mount houses
Holding the steering shaft by clamping
The lower mount housing with respect to the steering shaft.
An outboard motor characterized by stopping the housing . 2. The outboard motor according to claim 1, further comprising a steering bracket extending forward from an upper casing on which the engine is mounted and coupled to an upper end portion of the steering shaft, and the steering shaft being mounted on a steering bracket molding die. An outboard motor characterized by being loaded and cast.