JPH11324695A - Engine and small gliding boat equipped with above engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enlarge a generating capacity as the enlargement of a diameter of a rotor is restrained by attaching the rotor of a generator to the driving shaft of an auxiliary machine. SOLUTION: A front auxiliary machine (balancer) 19a is arranged in front of the web 39 of a front end cylinder. In addition, the balancer 19 is rotatably supported in parallel to a crank shaft 4 through a front auxiliary machine driving shaft (balancer shaft) 21a by a pair of bearings 42 severally maintained by a crank case 20 and a generator cover 41 attached to a front cover 43 covering the front end part of the crankcase 20. In front of the balancer 19a on a front balancer shaft 21a, a rotor 48 having a magnet 47 is fixed to the balancer shaft 21a so as to rotate integrally with the balancer 19a. Since the rotor 48 decided larger in a diameter is attached to the balance shaft 21 a located higher than the crank shaft 4, a rotor receiving part 51 in the crank case 20 does not protrude downward than a engine 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine having a structure in which an accessory drive shaft for driving an accessory such as a balancer for suppressing vibration of an engine body is rotatably connected to a crankshaft, and a small-sized engine equipped with the engine. It relates to a planing boat.

[0002]

2. Description of the Related Art An engine mounted on a personal watercraft of this type is provided with a generator. The structure of the generator is, for example,
A magnet rotor of a generator is rotatably connected to a crankshaft of an engine, and a stator of the generator is mounted on a generator cover that covers a front end surface of a crankcase, facing the magnet rotor (Japanese Patent Application Laid-Open No. 8-82215). reference).

[0003]

The personal watercraft of recent years is equipped with various electric devices such as a catalyst controller, a multimeter, and a fuel controller. It is desired to increase the power generation capacity of the generator. Therefore, it is conceivable to increase the diameter of the rotor in order to increase the power generation capacity. However, since the crankshaft to which the rotor is attached is usually arranged at the lower part of the engine, the crankshaft that accommodates the large-diameter rotor is used. Since the rotor storage portion of the case projects below the engine, the engine becomes taller. Since the engine is supported on the bottom wall of the hull, the entire engine must be located above to avoid the protrusions touching the bottom wall. Therefore, the center of gravity of the hull rises, the height of the hull increases, and the hull weight increases.

[0004] Therefore, the present invention provides an engine having a generator with a large power generation capacity and suppressing the height of the engine from increasing.
An object of the present invention is to provide a small personal watercraft in which the height and the center of gravity of the hull are suppressed from being increased by providing the same.

[0005]

In order to achieve the above object, the present invention provides an engine in which an auxiliary drive shaft for driving an auxiliary device is rotationally connected to a crankshaft. A rotor is attached.

According to the present invention, for example, by providing a plurality of generators by providing rotors on a plurality of accessory drive shafts, it is possible to increase the power generation capacity while suppressing an increase in the rotor diameter. In addition, if the auxiliary drive shaft is disposed above the crankshaft, the rotor housing does not protrude below the engine even when the generator has a large outer diameter to increase the power generation capacity. , The height of the engine does not increase. Therefore, when this engine is installed on the bottom wall of the personal watercraft, the center of gravity and height of the hull can be kept low. Further, since a drive shaft dedicated to driving the rotor is not required, the structure is not complicated.

In the present invention, it is preferable that the auxiliary drive shaft is disposed above the crankshaft. Thus, even if the outer diameter of the rotor of the generator is set to be large, the height of the engine does not increase because the rotor storage portion does not protrude below the engine.

In an embodiment of the present invention, a balancer shaft for driving a balancer is used as the accessory drive shaft. As a result, the rotor of the generator is generally mounted on the balancer shaft located above the crankshaft. Therefore, even if the rotor is set to have a large diameter, the rotor housing does not protrude below the engine. Therefore, the height of the engine does not increase. In addition, since the balancer shaft rotates at the same or twice the rotational speed as the crankshaft, a large power generation capacity can be obtained while minimizing the outer diameter of the rotor attached to this balancer shaft.

In the present invention, the rotor of the second generator may be attached to the crankshaft. As a result, since the generator is attached to both the accessory drive shaft and the crankshaft, a large power generation capacity can be obtained.
Therefore, it is not necessary to increase the diameter of the rotor of each generator, and the storage portion of the rotor attached to the crankshaft does not protrude below the crankcase. Therefore, the height of the engine does not increase.

A personal watercraft equipped with an engine according to the present invention comprises:
An auxiliary drive shaft to which a generator is attached is attached to the bottom wall of the hull with an engine arranged above the crankshaft. Since the height of this engine is maintained low even when the power generation capacity is increased, the mounting of this engine does not increase the height of the hull and does not increase the center of gravity.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a right side view of a personal watercraft equipped with a two-stroke engine according to a first embodiment of the present invention, and FIG. 2 is a plan view showing a power system of the personal watercraft. In FIG. 1, the hull 2 of the personal watercraft 1 is configured by joining an upper deck 2a and a lower hull 2b with respective flange portions F. The deck 2a has a seat 2c and a seat 2c. , A floor surface 2ds serving as a footrest is provided, and a handle 2e is provided in front of the seat 2c.

The two-stroke engine 3 mounted on the personal watercraft 1 of FIG. 2 has three cylinders 24 arranged in series.
The engine 3 is mounted on the hull 2b in such a direction that the axis of the crankshaft 4 coincides with the longitudinal direction of the hull 2 (the left-right direction in each figure). A propulsion shaft 8 is connected to the crankshaft 4 of the engine 3 via a coupling 7, and is disposed at the rear end of the engine 3 and the hull 2 via the crankshaft 4, the coupling 7 and the propulsion shaft 8. A propulsion device (water jet pump) 9 is rotatably connected to the propulsion device 9, and the propulsion device 9 is rotationally driven by the engine 3 and jets water from a nozzle 10 to obtain a propulsion force. The steering nozzle is not shown.

The exhaust gas from the engine 3 is supplied to the muffler section 1
An exhaust pipe (exhaust pipe) 12 having an exhaust pipe 1 is guided to a water muffler 13 disposed in the hull 2 and muffled exhaust gas is passed through a tail pipe 14 to a duct 1 containing a propulsion device 9.
5 is discharged. A fuel tank 17 is arranged in a space in front of the engine 3 in the hull 2.

FIG. 3 is a view of the arrangement of the engine 3 of the personal watercraft 1 as viewed from the stern side, and FIG. 4 is a partial longitudinal sectional view of the engine 3. In these figures, the same components as those in FIGS. 1 and 2 are denoted by the same reference numerals. 4, the engine 3 includes an in-line three-cylinder engine main body 18, a crankshaft 4 rotatably supported by the engine main body 18, and an auxiliary machine that is rotationally connected to the crankshaft 4 and suppresses vibration of the engine main body 18. It has two front and rear balancers 19a and 19b. Balancers 19a and 19b are balanced weights 2
2a, 22b and these balancer weights 22a, 22
balancer shafts 21a, 21 as auxiliary drive shafts for supporting the shaft b
1b and the balancer gears 23a and 23b are integrally formed.

On the other hand, balancer driving gears 27a and 27b are provided at both front and rear ends of the crankshaft 4, and both balancers 19a and 19b are provided with the balancer driving gears 27a and 27b.
The balancer gears 23a and 23b mesh with the 27b and are rotationally connected to the crankshaft 4. Therefore, both balancers 19 a and 19 b rotate in the opposite direction to the crankshaft 4. As shown in FIG. 3, the balancers 19a and 19b have their rotation center C2 located above the rotation center C1 of the crankshaft 4.

The crankcase 20 of the engine body 18 is attached to an engine mount 26 fixed to the bottom wall 2b1 of the hull 2b via a plurality of brackets 25 fixed to the crankcase 20.
Are supported by the bottom wall 2b1 of the hull 2. In the upper part of the crankcase 20, the cylinder 24 extending obliquely upward on one side (in this example, on the starboard side) from the axis C1 of the crankshaft 4 and an intake device 28 extending obliquely upward on the other side. They are arranged in a V-shape. The intake air introduction device 28 has a water trap structure, and includes an air inhaler 30 that takes in air from a diagonally downwardly directed intake port 29, a carburetor 31,
And a fuel supply valve (not shown) for mixing air with air from an air inhaler 30 in a carburetor 31 and mixing the lubricating oil downstream thereof with a lubricating oil supply path (not shown). It is supplied to the crank chamber 33. The air-fuel mixture that has entered the crank chamber 33 is moved downward by a piston (not shown).
And is sent to a combustion chamber above the piston through a scavenging passage (not shown). That is, the engine 3 is of a crankcase compression type.

An exhaust manifold 34 and an exhaust pipe 12 are disposed between a V-shaped structure composed of the cylinder 24 and the intake introducing device 28. The exhaust manifold 34, the exhaust pipe 12, the water muffler 13 and the tail pipe 14 shown in FIG.

In FIG. 4, a connecting rod 38 and a web 3 are attached to a piston (not shown) reciprocating in the cylinder 23.
The crankshaft 4 connected via the joint 9 is rotatably supported inside the crankcase 20 via a plurality of bearings 40. In addition, three intake reed valves 32 corresponding to each cylinder are mounted inside the crankcase 20 side by side in the axial direction of the crankshaft 4. The intake reed valve 32 prevents the air-fuel mixture from returning from the crank chamber 33 and introduces the air-fuel mixture into the crank chamber 20 from between a pair of webs 39 corresponding to each cylinder.

The front balancer 19a is disposed further forward than the front end (left end in FIG. 4) cylinder web 39, and the crankcase 20 and the crankcase 20 are connected via the front balancer shaft 21a. A pair of bearings 42 held on a generator cover 41 attached to a front cover 43 a covering the front end of the motor 20 are rotatably supported in parallel with the crankshaft 4. The rear balancer 19b is disposed further rearward than the web 39 of the rear end cylinder, and via the rear balancer shaft 21b,
A pair of bearings 44 held on the crankcase 20 and a rear cover 43b that covers the rear end face of the crankcase 20 rotatably support the crankcase 4 in parallel with the crankshaft 4.

The engine 3 is an in-line three-cylinder engine, in which the phases of the cylinders differ by 120 °, so that the mass of the rotating part around the crankshaft 4 is balanced in a symmetrical arrangement, and the piston shaft is reciprocated by the mass of the reciprocating part such as a piston. The vibrating force in the direction of the center becomes the largest vibration source, and the vibrating force of the cylinders located at the front and rear ends generates a moment that causes the entire engine to pitch and vibrate, but has opposite phases arranged one by one before and after. (The phases of the balancer weights 22a and 22b differ by 120 °)
Since the balancers 19a and 19b generate moments of the same magnitude in opposite phases to the moments of the corresponding cylinders, pitching vibration can be canceled.

A rotor 4 having a magnet 47 is provided at a position on the front side of the balancer shaft 21a before the balancer 19a.
8 is fixed to the balancer shaft 21a so as to rotate integrally with the balancer 19a, and a generator cover is opposed to the magnet 47 so that the stator 49 around which the generator coil is wound forms a generator 50 together with the rotor 48. 41 fixed.

Although not shown, the rotor 48
A pickup for taking out an ignition signal of the engine 3 and the like are arranged. As shown in FIGS. 3 and 4, the rotor 48 of the generator 50 has a larger outer diameter than a conventional rotor mounted on a crankshaft for the purpose of securing power for driving various accessories and devices. The diameter is set to increase the power generation capacity. As shown in FIG. 3, the engine 3 has a large-diameter rotor 48 attached to the balancer shaft 21a located above the crankshaft 4, so that the rotor 48 has a large diameter. , The rotor housing 51 in the crankcase 20 is
Does not protrude downward. That is, the height of the engine 3 is the same as that of the conventional engine in which the rotor of the generator is mounted on the crankshaft.

Therefore, the engine 3 is connected to the hull 2 via the bracket 25 of the same size as the conventional engine.
Can be installed close to the bottom wall 2b1, the center of gravity of the hull 2 can be kept low, and the height of the hull 2 does not increase, so that the hull weight does not increase. Further, since the rotor 48 of the generator 50 having a large power generation capacity is attached to the balancer shaft 21a, there is an advantage that the load on the shaft end that cantilever the crankshaft 4 can be reduced.

FIG. 5 is a partial longitudinal sectional view of an engine 3 according to another embodiment of the present invention. In FIG. 5, the same or equivalent components as those in FIG. Omitted. In the engine 3, similarly to the above-described embodiment, the rotor 48A having the magnet 47A is attached to the front balancer shaft 21a, and the stator 49A is opposed to the magnet 47A of the rotor 48A so that the generator cover 4
1 to form a first generator 54. In addition to this configuration, a rotor 57 having a magnet 58 is attached to the front end of the crankshaft 4, and the stator 59 is opposed to the magnet 58 so as to form a second generator 60 together with the rotor 57. 41.

In this engine, the predetermined power generation capacity is set to the first
And the second generators 54, 60, the rotors 48A, 48A,
Since both 57 do not have a large outer diameter, the crankcase 20 can be shaped so as not to project downward,
The height of the engine 3 does not increase. Therefore, the hull of the personal watercraft 1 equipped with the engine 3 is also maintained at a low center of gravity, and there is no increase in the height and weight of the hull. In addition,
In this embodiment, a rotor 5 mounted on the crankshaft 4 side for the purpose of reducing the shaft end load of the crankshaft 4.
7 is small and the rotor 48A on the balancer shaft 21a side is large, the noise (hitting sound) of the balancer gear 23a may increase due to the rotation delay on the balancer gear 23a side. It is sufficient to use gears and Caesars gears.

FIG. 6 is a schematic diagram showing still another embodiment of the present invention. In (a), first and second generators 54 and 60 are mounted on two front and rear balancer shafts 21a and 21b. By attaching the second generator 60 also to the balancer shaft 21b on the rear side, the rear portion of the crankshaft 4 is extended rearward so that the coupling 61 can be disposed at a position where it does not interfere with the second generator 60. ing.
(B) shows a configuration in which a first generator 54 is mounted on the front end of the crankshaft 4 and a second generator 60 is mounted on the balancer shaft 21b on the rear side. (C) shows that the first generator 54 is attached to the front-side balancer shaft 21a and the crankshaft 4
The second power generator 60 is provided at the rear end of the power generator. Therefore, an output gear 62 is fixed to the rear portion of the crankshaft 4, and an output shaft 63 is separately provided. An output shaft gear 64 that meshes with the output gear 62 is fixed to the output shaft 63. A ring 61 is provided.

Any one of the engines 3 shown in FIGS.
5, a predetermined power generation capacity is shared between the first and second generators 54 and 60, similarly to the engine of FIG. 5, so that the rotors of both the first and second generators 54 and 60 are Since it is not necessary to make the outer diameter large, the crankcase 20 can be formed into a shape that does not protrude downward. Therefore, the hull of the personal watercraft 1 equipped with these engines 3 is also maintained at a low center of gravity, and there is no increase in the height and weight of the hull. In addition, two generators 5
Since the wheels 4 and 60 are arranged at the front and rear ends, the weight balance is improved, and the occurrence of vibration can be suppressed.

In each of the above embodiments, the generator 5
The rotors 48, 57 of 0, 54, 60 are connected to the balancer shaft 2 which is the accessory drive shaft of the balancers 19a, 19b as accessories.
Although the case where the generator is mounted on the crankshaft 4 has been described as an example, the same effects as those of the above embodiment can be obtained even when the generator is mounted on the oil pump shaft or the water pump shaft.

[0029]

As described above, in the engine of the present invention, since the rotor of the generator is attached to the auxiliary drive shaft, for example,
By providing a plurality of generators by providing the rotor on a plurality of accessory drive shafts, it is possible to increase the power generation capacity while suppressing an increase in the rotor diameter. Further, if the auxiliary drive shaft is disposed above the crankshaft, the rotor housing does not protrude below the engine even when the diameter of the rotor of the generator is set large to increase the power generation capacity. The height of the engine does not increase. Therefore, the engine can be installed on the bottom wall of the personal watercraft to keep the center of gravity and height of the hull low. Also,
Since a drive shaft dedicated to driving the rotor is not required, the structure is not complicated.

In the personal watercraft according to the present invention, an engine having a configuration in which an auxiliary drive shaft to which a generator is mounted is disposed above the crankshaft is mounted on the bottom wall of the hull. Even if the power generation capacity is increased, the height is maintained low, so that the mounting of this engine does not increase the height and weight of the hull and does not increase the center of gravity of the hull.

[Brief description of the drawings]

FIG. 1 is a side view showing a personal watercraft equipped with an engine according to an embodiment of the present invention.

FIG. 2 is a plan view showing an arrangement state of a power system of the personal watercraft.

FIG. 3 is a cross-sectional view of the engine of the personal watercraft as viewed from the stern side.

FIG. 4 is a partial longitudinal sectional view of the engine taken along a line IV-IV passing through axes C1 and C2 in FIG. 3;

FIG. 5 is a partially broken right side view of an engine according to another embodiment of the present invention.

6 (a) to 6 (c) are schematic diagrams corresponding to FIGS. 4 and 5 showing an engine according to a different embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Small personal watercraft, 2 ... Hull, 2b1 ... Bottom wall, 3 ... Engine, 4 ... Crankshaft, 19a, 19b ... Balancer (auxiliary equipment), 23a, 23b ... Balancer shaft (auxiliary equipment drive shaft), 4
8, 48A, 57: rotor, 50: generator, 54: first
Generator, 60 ... second generator.

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[Procedure amendment]

[Submission date] June 18, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0005

[Correction method] Change

[Correction contents]

[0005]

According to one aspect of the present invention , there is provided an engine in which an accessory drive shaft for driving an accessory is rotatably connected to a crankshaft. A shaft is disposed above the crankshaft,
A rotor of a generator is attached to each of the crankshaft and the accessory drive shaft .

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction contents]

According to the present invention, the rotor is connected to the crankshaft and
By providing a plurality of generators provided on the auxiliary drive shaft and the accessory drive shaft , it is possible to increase the power generation capacity while suppressing an increase in the diameter of the rotor. The auxiliary drive shaft is located above the crankshaft.
Accordingly , even when the outer diameter of the rotor of the generator of the auxiliary drive shaft is set large to increase the power generation capacity, the rotor storage portion does not protrude below the engine. No. Therefore, when this engine is installed on the bottom wall of the personal watercraft, the center of gravity and height of the hull can be kept low. Further, since a drive shaft dedicated to driving the rotor is not required, the structure is not complicated.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

In the present invention, the rotor of the auxiliary drive shaft is provided.
It is preferable that the outer diameter be larger than the outer diameter of the rotor of the crankshaft . As a result, the auxiliary drive shaft is
, The outer diameter of the auxiliary drive shaft rotor
Increase the power generation capacity by setting it larger than the rotor outer diameter of the link shaft.
Even when the size is increased, the height of the engine does not increase because the rotor storage portion does not protrude below the engine.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

According to another configuration of the present invention , the crankshaft has
An engine with an auxiliary drive shaft that drives the auxiliary
The auxiliary drive shaft is located above the crankshaft.
And supplementary parts arranged at both front and rear ends of the crankshaft.
The generator rotor is attached to each of the machine drive shafts.
ing. According to the present invention, the rotor is connected to both front and rear of the crankshaft.
A plurality of accessory drive shafts are provided at each end.
Constructing a generator suppresses increase in rotor diameter
Meanwhile, the power generation capacity can be increased. Also, the auxiliary drive shaft
The auxiliary drive shaft is located above the crankshaft.
Increase the generator capacity by setting the rotor outer diameter of the generator to be large.
Even when large, the rotor storage section is located below the engine.
Since it does not protrude, the height of the engine does not increase.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

In an embodiment of the present invention, the auxiliary drive shaft is
And a balancer shaft for driving the balancer. This
The balancer shaft has the same or twice the rotational speed as the crankshaft.
The rotor attached to this balancer shaft
Large power generation capacity while minimizing the outer diameter of
You. Also, at the top of the crankcase, the axis of the crankshaft
A cylinder extending diagonally upward from one side
It is preferable that

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction contents]

FIG. 3 is a view of the arrangement of the engine 3 of the personal watercraft 1 viewed from the stern side, and FIG. 4 explains the principle of the present invention .
Is a partial longitudinal sectional view of an engine 3 for the vehicle. In these figures, the same components as those in FIGS. 1 and 2 are denoted by the same reference numerals. In FIG. 4, an engine 3 includes an in-line three-cylinder engine main body 18, a crankshaft 4 rotatably supported by the engine main body 18, and an auxiliary machine that is rotationally connected to the crankshaft 4 and suppresses vibration of the engine main body 18. It has two front and rear balancers 19a and 19b. Balancer 19a,
Reference numeral 19b denotes balancer weights 22a and 22b, balancer shafts 21a and 21b serving as auxiliary drive shafts for supporting the balancer weights 22a and 22b, and the balancer gear 2
3a and 23b are integrally formed.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0029

[Correction method] Change

[Correction contents]

[0029]

As it is evident from the foregoing description, the engine of the present invention, b
By providing the motors on the crankshaft and the accessory drive shaft to form a plurality of generators, it is possible to increase the power generation capacity while suppressing an increase in the rotor diameter. By arranging the accessory drive shaft above the crankshaft, even when the outer diameter of the rotor of the generator of the accessory drive shaft is set large to increase the power generation capacity, Since the storage portion does not protrude below the engine, the height of the engine does not increase. Therefore, the engine can be installed on the bottom wall of the personal watercraft to keep the center of gravity and height of the hull low. Further, since a drive shaft dedicated to driving the rotor is not required, the structure is not complicated.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Change

[Correction contents]

[Brief description of the drawings]

FIG. 1 is a side view showing a personal watercraft equipped with an engine according to an embodiment of the present invention.

FIG. 2 is a plan view showing an arrangement state of a power system of the personal watercraft.

FIG. 3 is a cross-sectional view of the engine of the personal watercraft as viewed from the stern side.

FIG. 4 is a diagram illustrating the principle of the present invention .
FIG. 4 is a partial longitudinal sectional view of the engine taken along a line IV-IV passing through C1 and C2.

FIG. 5 is a partially broken right side view of an engine according to another embodiment of the present invention.

6 (a) to 6 (c) are schematic diagrams corresponding to FIGS. 4 and 5 showing an engine according to a different embodiment of the present invention.

Claims (5)

[Claims] 1. An engine in which an accessory drive shaft for driving an accessory is rotatably connected to a crankshaft, wherein a rotor of a generator is attached to the accessory drive shaft. 2. The vehicle according to claim 1, wherein the auxiliary drive shaft is
An engine disposed above the crankshaft. 3. The engine according to claim 1, wherein the accessory drive shaft is a balancer shaft that drives a balancer. 4. The engine according to claim 1, wherein a rotor of a second generator is mounted on the crankshaft. 5. A personal watercraft in which the engine according to claim 2 is mounted on a bottom wall of a hull.