JP3324487B2 - Engine structure of hydroplane - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a personal watercraft in which an engine is mounted inside a hull and the power of the engine is transmitted to a propulsion device at a rear portion of the hull and propelled. The present invention relates to a watercraft having an engine having a structure for transmitting water to a watercraft.

[0002]

2. Description of the Related Art Conventionally, a watercraft (also referred to as a small watercraft) is a boat mainly intended for leisure use.
It is gaining popularity because the occupant can freely slide on the water by manipulating the steering wheel and throttle grip across the seat, and as if it has a control feeling like a motorcycle, it is also called a watercraft. Is what is being done.

In a watercraft of this type, for example, as shown in FIG.
In general, the engine is placed parallel to the traveling direction of the hull, and the rotation of the engine is directly transmitted to the propulsion device. In this type of engine, the propulsion device is driven to rotate at one end a1. In this case, the electric power is generated by attaching the magnet rotor b1 of the flywheel magnet type generator b to the crankshaft end a2 at the end opposite to the propulsion device side, and generating the electric power by rotation of the engine. In FIG. 9, c is a crankpin, which constitutes a three-cylinder engine.

However, when the crankshaft direction of the engine is arranged along the traveling direction of the watercraft as described above, there is no room in front and rear in the hull, and it becomes difficult to mount a fuel tank and other equipment. In some cases, the crankshaft of the multi-cylinder engine is arranged at right angles to the longitudinal direction of the hull, and its rotation direction is changed and transmitted to the propulsion device.

In this type of watercraft, for example, as shown in FIG. 10, the crankshaft d of the multi-cylinder engine is mounted at right angles to the hull in the traveling direction, so that the output shaft is at right angles to the crankshaft d. Drive gear f1 of parallel gear from crankshaft d and driven shaft g by driven gear f2
And the rotation direction of the driven shaft g is changed to a right angle by the bevel gear drive gears h1 and h2 to rotate the propulsion shaft. In a watercraft with such a power transmission path, since the total length of the engine is difficult to be reduced because of the multi-cylinder, there is no space for mounting the magnet rotor at the end of the crankshaft d. In this case, in order to transmit the rotational force of the crankshaft d to the alternator i, which is a generator, the driving force is transmitted from the driven shaft g by a gear j or a pulley or a chain to generate electric power.

[0006]

However, transmitting the engine rotational force to the generator by means of gears or the like as described above requires extra gears and the like, which leads to an increase in cost and a space for mounting the generator. However, there is also a problem that the space is required and the freedom of use of the space is lost because the space is required around the driven shaft.

In the watercraft, the bevel gear for changing the direction of the drive shaft has a drive gear h1 mounted on one side of a driven shaft g, and is mounted on an output shaft e with the other driven gear h2 facing each other. However, it is necessary to adjust the tooth contact after assembling the bevel gears h1 and h2 or during maintenance. However, there is a method of finely adjusting the contact of the teeth by inserting a thin plate (shim) into the end surfaces of the bearings g1 and g1 that support the driven shaft g. To perform this adjustment, it is necessary to disassemble the crankcase. However, there is a problem that the assemblability and maintainability are poor.

[0008] In addition, when a hydroplane is equipped with a wet sump system when a four-stroke engine is mounted, an oil pan is provided below the engine, so that the overall height of the engine increases and the mountability of the engine on the hull deteriorates. Problems arise. In order to solve this problem, it is preferable to employ a dry sump method. In this dry sump method, it is preferable to employ an oil pump (scavenging pump) for collecting oil in addition to the conventional lubrication oil pump.
However, in order to drive the oil pump for recovery, a shaft, gears, and the like must be arranged in the engine case, which causes a disadvantage that the engine structure is complicated and large.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and provides an engine structure of a personal watercraft that can reduce the left and right length of an engine mounted at right angles to the hull in the traveling direction. The purpose is to: Another object of the present invention is to provide an engine structure of a personal watercraft that can easily adjust the tooth contact of the bevel gear without disassembling the engine case. It is another object of the present invention to provide an engine structure for a small personal watercraft that employs a dry-sump system for a four-cycle engine and can reduce the complexity and size of the engine even when a recovery pump is mounted.

[0010]

The present invention has the following configuration to achieve the above object. The invention of claim 1 is
A rotatable operation handle is provided substantially at the upper center of the hull, and a long seat is provided at the rear of the handle in the front-rear direction. Steps are provided on both left and right sides of the seat. Is mounted with a four-cycle multi-cylinder engine that is placed horizontally in the direction perpendicular to the hull's direction of travel, and the engine drives a jet pump at the rear of the hull via an impeller shaft parallel to the direction of the hull's travel to propell An engine structure for a watercraft, wherein a valve driving gear for extracting valve driving force from a crankshaft and a power extracting gear for extracting driving force for an impeller shaft are arranged on a crankshaft between cylinders at left and right ends of the boat. It is. The invention according to claim 2 is the engine structure for a watercraft according to claim 1, wherein the valve drive gear is provided at the center of the crankshaft and at the center of the hull. According to a third aspect of the present invention, the power take-off gear is disposed in a cylinder adjacent to the center of the crankshaft, and the driven shaft driven by the power take-off gear is disposed behind the crankshaft. The engine structure of a watercraft according to claim 1 or 2, wherein a drive shaft of the watercraft is connected, and the generator is disposed behind the crankshaft and within the crankshaft width. According to a fourth aspect of the present invention, the power take-off gear is disposed in a cylinder adjacent to the center of the crankshaft, and the driven shaft driven by the power take-off gear is disposed behind the crankshaft;
The drive shaft of a flywheel type generator is connected to the driven shaft, and an oil pump is provided on a side of the driven shaft opposite to a side where the generator is provided. 2 is an engine structure of the watercraft.
According to a fifth aspect of the present invention, there is provided an engine structure for a personal watercraft according to the fourth aspect, wherein each of the oil pumps is provided with an oil pump and an oil recovery pump in series with the oil pump shaft. .

According to a sixth aspect of the present invention, the driven shaft and the output shaft for driving the impeller shaft are rotated at right angles by a bevel gear, and the driven shaft has a bearing structure in which one side of the driven shaft is a ball bearing and the other side is a roller. The ball bearing is supported by a bearing, and the ball bearing is installed in a housing whose position in a driven axial direction can be adjusted with respect to an engine case. It is an engine structure of description. According to a seventh aspect of the present invention, in the bearing structure of the output shaft, one side is supported by a ball bearing and the other side is supported by a roller bearing, and the ball bearing can adjust the position in the output axis direction with respect to the engine case. The engine structure of a personal watercraft according to claim 6, wherein the engine structure is installed in a watercraft.

According to the first aspect of the present invention, there is provided a watercraft in which an engine is arranged at right angles to a traveling direction of a crankshaft thereof. Since it is arranged on the crankshaft between the cylinders at both ends in the direction, the length of the crankshaft can be reduced as compared with arranging a valve drive gear and / or a power takeoff gear at the end of the crankshaft. The overall width can be reduced.
According to the second aspect of the present invention, since the valve drive gear is provided at the center of the crankshaft and at the center of the hull, the valve drive gear and the power transmission chain and the valve shaft gear engaged with the valve drive gear are provided at the center of the engine. And the weight balance between the left and right is improved. According to the third aspect of the present invention, the power take-out gear is disposed in the cylinder adjacent to the center of the crankshaft, and the driven shaft driven by the power take-out gear is disposed behind the crankshaft. Since the magnet rotor of the flywheel type generator was arranged and the generator was arranged behind the crankshaft and within the crankshaft width, the driven shaft and the generator were stored within the crankshaft width,
The whole engine can be made compact. In addition, the flywheel type generator has a magnet rotor at the driven shaft end, so there is no need for extra parts such as gears and pulleys as when using an alternator, and the mounting space can be made compact, And the overall width of the engine can be kept to a minimum. Claim 4
According to the invention, the power takeoff gear is disposed in the cylinder adjacent to the center of the crankshaft, the driven shaft driven by the power takeoff gear is disposed behind the crankshaft, and the flyshaft generator is attached to the driven shaft. And the oil pump is provided on the opposite side of the driven shaft from the generator side, so that the oil pump can be arranged on the opposite side of the generator, and the weight balance between the left and right is improved. . According to the fifth aspect of the present invention, since the oil pump and the oil recovery pump are arranged in series with the oil pump shaft, parts required for driving can be minimized, and Since the pumps for oil pressure feeding and oil recovery are arranged on the side opposite to the side where the magnet rotor is mounted, it is possible to achieve compactness while maintaining the right and left balance of the engine.

According to the invention of claim 6, the rotation direction of the driven shaft and the output shaft for driving the impeller shaft is changed to a right angle by the bevel gear. Here, if the driven shaft is supported at both ends by ball bearings, the ball bearing is fixed by fitting the outer to the crankcase, and the inner is fixed to the driven shaft. If the axial position of the driven shaft is changed for the adjustment, it is necessary to disassemble the crankcase and adjust the fitting position of the outer of the ball bearing by inserting a shim or the like. On the other hand, in the invention of claim 6, in the bearing structure of the driven shaft, one side (outside) of the driven shaft is supported by a ball bearing and the other side (inside) is supported by a roller bearing. The roller bearing supports the driven shaft movably in the axial direction. Further, since the ball bearing is installed in a housing whose position in the driven axial direction can be adjusted with respect to the engine case, the position of the ball bearing can be adjusted by adjusting the position of the housing. Therefore, when adjusting the tooth contact of the bevel gear, simply adjust the installation position of the housing in which the ball bearings are installed with respect to the crankcase by interposing a shim or the like, the position of the ball bearings changes, and the others are roller bearings. Since the driven shaft is slidably supported in the axial direction, the driven shaft can be adjusted in position only by adjusting the housing to adjust the tooth contact of the bevel gear. Therefore, the tooth contact of the bevel gear can be adjusted without the necessity of disassembling the crankcase, so that the adjustment operation is extremely easy. According to the seventh aspect of the present invention, the bearing structure of the output shaft is, similarly to the driven shaft of the sixth aspect, supported on one side by a ball bearing and on the other side by a roller bearing. Since it is installed in a housing whose position in the driven axial direction can be adjusted with respect to the case, the position of the ball bearing can be adjusted by adjusting the position of the housing. Therefore, when adjusting the tooth contact of the bevel gear, the position of the ball bearing changes only by adjusting the installation position of the housing in which the ball bearing is installed with respect to the crankcase by interposing a shim or the like.
The other is a roller bearing, which supports the output shaft so that the axial position is slidable, so that the driven axial position can be adjusted and the tooth contact of the bevel gear can be adjusted only by adjusting the housing.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are an overall side view and a plan view of the watercraft according to the present embodiment. As shown in FIGS. 1 and 2, the watercraft has a four-cylinder four-cylinder engine 6 and a jet pump 8 arranged in front and rear in a hull 1, and an exhaust port for each cylinder of the engine 6. The pipes 21 are connected, and each downstream end of the plurality of exhaust pipes 21 is connected to a collecting pipe 23.
Of the exhaust pipe 42 from the collecting pipe 23.
Is connected to a muffler 48 which forms an expansion chamber.
Further, the plurality of exhaust pipes 21 connected to each cylinder have substantially the same length, and are connected to one expanded collecting pipe 23 so as to equalize the exhaust pressure of each cylinder and improve the engine output. I made it.

The hull 1 is integrally formed of various synthetic resins. As shown in FIG. 1, a steering handle 2 rotatable toward the front of a substantially upper center in the front-rear direction is provided. The seat 3 is provided with a vertically long seat 3 and a step (not shown) for placing a foot is integrally formed on each of the left and right sides of the seat 3, so that the occupant can ride over the seat 3 or stand on the step. By manipulating the steering handle 2 and the like as appropriate, the vehicle glides on the water surface.

The hull 1 is structured in consideration of straight running stability and suppression of reaction force. As shown in FIG. 2, a plurality of mounts are mounted in an engine room at a position slightly shifted forward from the center of the hull 1. A large, in-line engine 6 is installed vertically upright via rubber and a mount frame. Also,
In front of the engine 6 in front of the hull 1, the engine 6
A fuel tank 7 for storing fuel to be supplied to the hull 1 is installed, and a jet pump 8 that is directed in the front-rear direction of the hull 1 is installed in a pump chamber near the rear end at the center of the inside.

The engine room is configured to introduce air through a plurality of air circulation ducts (not shown). As shown in FIGS. 1 and 2, the engine 6 includes a crankcase 9 at a lower portion thereof, and a cylinder 11 having a cylinder head 10 at an upper portion is vertically attached to the crankcase 9. Inside the crankcase 9 is a crankshaft 12 that is placed horizontally in a direction perpendicular to the direction of travel of the hull 1.
Are supported via a plurality of bearings, and the crankshaft 12 is a power take-out gear 29, a driven gear 31, and a bevel gear 33A, 33B serving as a power transmission mechanism (see FIGS. 3 and 4 described later) inside the crankcase 9. The power transmission mechanism functions to convert the rotational driving force of the crankshaft 12 by 90 ° and to transmit the rotational driving force at a reduced speed.

Therefore, the engine 6 is connected to the cylinder 11
Are arranged in the horizontal direction of the hull 1. An intake system device such as a carburetor 15 is installed above and in front of the center line of the crankshaft 12, and one side (for example, port side) behind the center line of the crankshaft 12 is provided with the engine 6. An oil tank 16 for lubrication is provided via an oil pipe, and a relatively large space in the front-rear direction is utilized very efficiently. An electrical component box 13 is provided on the opposite side of the collecting pipe 23 of the oil tank 16, and a battery 14 is provided on the opposite side of the oil tank 16 across the casing 19 of the muffler 48. 1 to balance the left and right weight.

As shown in FIG. 1 and FIG. 2, the jet pump 8 is made of stainless steel which is inclined on the center line of the hull 1 (ie, parallel to the traveling direction of the hull 1 in plan view) in side view. An impeller shaft 17 is provided.
Is connected to the output shaft of the power deflection mechanism via a rubber coupling 18. An impeller that rotates inside the casing 19 is housed at the end of the impeller shaft 17. Water is drawn up from an opening (not shown) at the rear lower portion of the hull 1 by the rotation of the impeller, and the impeller rotates rearward from the nozzle 20. Water is injected to gain propulsion.

The cylinder 11 is arranged substantially perpendicularly to the center extension of the impeller shaft 17. A stator (not shown) is fixed inside the casing 19. Further, the nozzle 20 is configured to swing based on a steering operation of the steering handle 2, and the swing of the watercraft is steered. Further, a cooling water inlet (not shown) is provided on the discharge side of the jet pump 8, and the cooling water is supplied from the cooling water inlet to the plurality of exhaust pipes 21, respectively.

As shown in FIG. 1, a plurality of (four in the present embodiment) exhaust pipes are composed of a plurality of pipes having substantially the same length.
The exhaust port 0 is curved and connected to the rear of the crankshaft 12, and its downstream end is gathered substantially above the crankcase 9 and penetrates and connected to the collecting pipe 23.

FIG. 3 shows the internal structure of the engine 6 of the personal watercraft according to the first embodiment. Engine 6
The arrangement of the cylinders is No. 1 to No. 4 in order from the right side in the traveling direction of the illustrated watercraft.

The engine 6 has a crankcase 9 divided vertically, and FIG. 3 shows a state in which the upper structure of the crankcase 9 is removed from the crankshaft 12. FIG.
As shown in FIG. 1, the crankcase 9 has a substantially rectangular shape in which the rear left portion is cut out by about 1/3 in a plan view, and the driven shaft 30 described later on the front of the crankcase 12 and the crankshaft 12 on the rear. They are arranged in parallel and at right angles to the hull advancing direction. Also, crankshaft 1
The output shaft 34 described later on a line C extending the center position of
Is arranged.

As shown in FIG. 3, a crankshaft 12 is disposed in the engine 6 along a direction perpendicular to the hull advancing direction, and the crankshaft 12 is provided with a piston connecting rod (not shown) of each cylinder. Four crank pins 24, 24... Rotatably connected to the large end are provided for each cylinder.
Crank webs 25, 25,... Are formed on both sides of each of the crank pins 24, 24,.
5, 25 ... between the crankshaft journal portions 26, 2
6 are formed. The journal portion 26 is supported by bearings 27, 27,... Installed on the crankcase 9. The bearings 27, 27,. Between No.3 and No.4
No. 2 and N
In the center of the crankshaft 12 between the cylinders of o.3, two are provided at intervals.

At a substantially central portion of the crankshaft 12, there is provided a gear (valve drive gear) 28 for taking out a driving force for opening and closing valves (intake valve and exhaust valve) from the crankshaft 12. On both sides of the position where the valve drive gear 28 of the crankshaft 12 is disposed, journal portions 26 are formed.
It is supported at 7. Further, the valve driving gear 28
Is provided at the center of the crankshaft 12 so as to be located at the center of the hull.

The power take-off gear 29 is disposed in a cylinder adjacent to the center of the crankshaft 12. In the embodiment, the crankshaft 12 is provided with a power take-out gear 29 for taking out the driving force of the impeller shaft 17 between the cylinders (No. 1 and No. 4) at both ends in the left-right direction and adjacent to the center of the crankshaft. In this case, it is arranged on the outer periphery of the outer crank web 25 on the crankshaft 12 of the No. 2 cylinder.

A driven shaft 30 driven by the power take-off gear 29 is disposed parallel to the rear of the crankshaft 12. A power take-out gear is provided on the driven shaft 30.
A driven gear 31 with which the gear 9 meshes is fixed, and the rotation of the crankshaft 12 is transmitted to the driven shaft 30 at a desired speed ratio by these gears 29 and 31. The driven shaft 30 has a magnet rotor 32A of a flywheel type generator 32 fixed to the right end thereof. The generator 32 is located behind the crankshaft 12, and the right end position of the generator 32 is the crankshaft. The generator 32 is arranged within the right end portion 12 (indicated by a two-dot chain line 12R), that is, the generator 32 is arranged within the width of the crankshaft 12. An opening 9a is formed in the crankcase 9 facing the outside of the generator 32, and the opening 9a is formed to have a diameter larger than the outer diameter of the generator 32 and is opened and closed by a substantially plate-shaped lid member 9c. When the lid 9c is opened, inspection and adjustment of the generator 32 can be performed without disassembling the crankcase 9.

An impeller shaft 17 is disposed on a center line C extending rearward from the center position of the crankshaft 12. The impeller shaft 17 is connected to the impeller shaft 17 in the engine 6 and outputs driving force (impeller shaft). The output shaft 34 (for driving) is disposed behind the crankshaft 12 and on the center line C. Therefore, the crankshaft 12 and the driven shaft 30 are disposed in parallel, and the output shaft 34 and the impeller shaft 17
Are arranged at right angles to them. The output shaft 34
Has a front end extending forward of the driven shaft 30 to a position adjacent to the crankshaft 12.

The driven gear 31 of the driven shaft 30
The input-side bevel gear 33A is disposed at the opposite end of the generator 32 with respect to the center of the engine 6, that is, at the end on the center side of the engine 6.
An output bevel gear 33B is fixed to the front end of the output shaft 34, and the input bevel gear 33B is fixed to the output shaft 34.
A and the output side bevel gear 33B mesh with each other, and the driven shaft 30 and the output shaft 34
A and 33B convert the rotation direction to a right angle.

In the engine 6 of the first embodiment, the bearing of the driven shaft 30 is a pair of ball bearings 35 disposed on both sides of the driven gear 31.
The bearing of the output shaft 34 includes a needle bearing (an example of a roller bearing) 36 that supports the front end of the output shaft 34 and a ball bearing 37 provided on the opposite side of the needle bearing 36 across the bevel gear 33B.
It is. This ball bearing 37 is used for the crankcase 9.
The output shaft 34 is supported in a state of being fixedly fastened to a separate bearing housing 38.

More specifically, the bearing housing 38
Has a substantially cylindrical shape having substantially the same diameter and length in the axial direction, and has a flange 38A at one end (end of the rear impeller shaft 17 side).
Are formed to protrude. The bearing housing 38, which supports the output shaft 34, is inserted into the rear opening 9b of the crankcase 9 from behind, and is fastened and fixed with bolts. The position of the bearing housing 38 relative to the crankcase is adjusted by a shim 39 interposed between the rear end face of the crankcase 9 and the front end face of the flange 38A of the bearing housing 38. A shim 40 for adjusting the axial position of the driven shaft 30 is also interposed between the ball bearings 35 and 35 of the driven shaft 30 and the bearing fixing portion of the crankcase.

According to the watercraft of the first embodiment, the engine 6 is provided with the crankshaft 12 at right angles to the traveling direction.
2, a valve driving gear 28 for extracting the valve driving force and a power extracting gear 2 for extracting the driving force of the impeller shaft 17.
9 is disposed on the crankshaft 12 between the cylinders at both ends in the left-right direction, the length of the crankshaft 12 is shorter than that in which these valve driving gears and / or power take-out gears are disposed at the end of the crankshaft 12. As a result, the overall width of the engine can be reduced.

Since the valve drive gear 28 is provided at the center of the crankshaft 12 and at the center of the hull, the valve drive gear 28 and a power transmission chain and a valve shaft gear (not shown) engaged with the valve drive gear 28 are provided in the engine. 6, the engine 6 and thus the weight balance between the left and right hulls is improved.

The power take-off gear 29 is disposed in a cylinder adjacent to the center of the crankshaft 12, and a driven shaft 30 driven by the power take-off gear 29 is disposed behind the crankshaft 12; The magnet rotor 32A of the flywheel type generator 32 is arranged in
The generator 32 is connected to the rear of the crankshaft 12 and the crankshaft 12.
Since the driven shaft 30 and the generator 32 are arranged within the width of the crankshaft 12, the entire engine 6 can be made compact. Further, since the flywheel type generator 32 has the magnet rotor 32A disposed at the end of the driven shaft 30, gears and gears are used as in the case where an alternator is used.
It does not require extra parts for pulleys, etc.
The mounting space can be made compact, and the overall width of the engine 6 can be minimized.

As with the driven shaft 30, the bearing structure of the output shaft 34 is similar to that of the driven shaft 30. The side (one side) closer to the crankshaft 12 is the ball bearing 37, and the side of the impeller shaft 17 (the other side) is the output shaft 34. The directional position is supported by a needle bearing (roller bearing) 36 slidably supported. And the ball bearing 3
Reference numeral 7 denotes a bearing housing 38 that can adjust the position of the output shaft 34 with respect to the engine case 9.
Therefore, if the position of the housing 38 is adjusted, the position of the ball bearing 37 can be adjusted. Therefore, when adjusting the tooth contact of the bevel gears 33A and 33B, the installation position of the housing 38 in which the ball bearing 37 is installed with respect to the crankcase 9 is adjusted by exchanging shims 39 having various thicknesses. The position is changed, and the other is
4 is slidably supported in the axial direction.
Only by adjusting the housing 38 to the crankcase 9, the axial position of the output shaft 34 can be adjusted to adjust the contact of the bevel gears 33A and 33B to some extent.

Next, the engine 50 of the personal watercraft according to the second embodiment will be described with reference to FIGS. In FIG. 4 and the following description, the same parts as those in FIGS.

As shown in FIG. 4, in the engine 50 of the second embodiment, the driven shaft 30 and the output shaft 34 for driving the impeller shaft are rotated at right angles by bevel gears 33A and 33B. Unlike the first embodiment,
The bearing structure of the driven shaft 30 includes a ball bearing 51 on the outside (one side) across the driven gear 31 of the driven shaft, and a roller bearing 52 on the inside (the other side) that supports the driven shaft 30 so that the axial position can be changed. The ball bearing 51 is mounted on a bearing housing 53 that can adjust the position of the driven shaft 30 with respect to the crankcase 9.

The bearing housing 53 has a substantially hollow short cylindrical shape with a flange 53A formed on the right side.
The ball bearing 51 is fitted into the inner peripheral portion, and the driven shaft 30 is inserted therein. With the flange 53 </ b> A positioned outside, the receiving portion 5 erected integrally inside the crankcase 9.
The flange 53A faces the outer end surface 54A of the receiving portion 54 and is fastened with a bolt 55. The outer end surface 54A and the flange 53
5, a shim 56 having a substantially arc shape as shown in FIG. 5 is interposed. If the shim 56 is replaced with a shim of various thicknesses, the crankcase of the bearing housing 53 can be replaced. The mounting position with respect to 9 can be adjusted. The shim 56 shown in FIG. 5 has a substantially arc shape, and has both ends formed in a ring shape so as to be held by a tool.

As described above, the engine 50 according to the second embodiment
Then, the bearing structure of the driven shaft 30 is
Is supported by a ball bearing 51 on the outside and a roller bearing 52 on the inside. The roller bearing 52 supports the driven shaft 30 so as to be movable in the axial direction.
Since the ball bearing 51 is installed in a bearing housing 53 whose position in the driven shaft 30 can be adjusted with respect to the engine case 9, the position of the housing 53 can be adjusted.

Therefore, the bevel gears 33A, 33B
When adjusting the contact between the teeth, the position of the ball bearing 51 changes only by adjusting the installation position of the housing 53 in which the ball bearing 51 is installed with respect to the crankcase 9 by interposing shims 56 of various thicknesses. The other is a roller bearing 52, driven shaft 3
0 is slidably supported in the axial direction, so
Only by adjusting the housing 53, the position of the driven shaft 30 in the direction can be adjusted to adjust the contact of the bevel gears 33A and 33B. Therefore, since it is possible to adjust the contact of the bevel gears 33A and 33B without disassembling the crankcase 9, the adjustment operation is extremely easy.

The power generator 3 with the cover member 9c opened.
2 by removing the bearing housing 53
Therefore, even when the crankcase 9 is not disassembled, the position of the driven shaft 30 can be adjusted by loosening the bolt 55 and replacing the shim 56. Therefore, maintainability is extremely good.

As with the driven shaft 30, the bearing structure of the output shaft 34 is the ball bearing 37 on the side (one side) close to the crankshaft 12, and the needle bearing (roller bearing) is on the side of the impeller shaft 17 (other side). ) 36 and can be adjusted in the same manner as in the first embodiment. Therefore, the tooth contact of the bevel gears 33A, 33B can be finely and precisely adjusted from both the driven shaft 30 side and the output shaft 34 side.

FIGS. 6 to 8 are explanatory diagrams of the engine 60 according to the third embodiment. FIG. 6 is an internal view of the engine 60 according to the third embodiment, FIG. 7 is an explanatory diagram of each gear such as a pump driving gear when the engine 60 is viewed from the side, and FIG. 8 is an explanatory diagram of the arrangement of each pump. is there. The same reference numerals are given to the same parts as in the third embodiment, and the description is omitted.

In the engine 60, the magnet shaft 32 of the flywheel type generator 32 is attached to the driven shaft 30.
A and a pump 61 for lubricating oil supply and an oil recovery pump 62 as a scavenging pump are provided on the driven shaft 30 on the side opposite to the generator 32 side.
And are arranged. An oil pressure pump 61 and an oil recovery pump 62 are arranged in series with the oil pump shaft 63.

That is, as shown in FIGS. 6 to 8, an oil pump drive gear 64 is formed adjacent to the driven shaft 31 of the driven shaft 30 on the output shaft side. The drive gear 64 can be formed integrally with the driven gear 31. Of course, they may be separate. And
As shown in FIG. 7, the drive gear 64 transmits a driving force to an oil pump driven gear 66 via an idle gear 65 having a shaft below and behind the driven shaft 30. The idle gear 65 ensures the degree of freedom in the position design of the oil pump shaft 63. However, if the design and conditions permit, the idle gear 65 is abolished and the oil pump driven gear 66 is directly replaced with the oil pump drive gear 64. It is also within the scope of the present invention to engage.

The oil pump shaft 63 includes a crankshaft 1
2 and extends in the opposite direction to the generator 32. A drive shaft 61A of an oil pressure pump 61 is coaxially connected to the tip of the pump shaft 63, and the drive shaft 61A is connected to an oil recovery pump 62. Is coaxially connected to the drive shaft 62A of
The pumps 61 and 62 are connected in series. The opposite end (left end) of the generator 32 of the oil recovery pump 62 is located inside the end of the crankshaft 12 (left end 12L). The oil pressure pump 61 is a trochoid pump,
Oil recovery pump 62 can be a gear pump

In the engine 60 of the third embodiment, the oil pump 6 is mounted on the driven shaft 30 on the side opposite to the side where the generator 32 is provided.
The provision of 1, 62 improves the right and left weight balance of the engine 6. Also, since the oil pressure pump 61 and the oil recovery pump 62 are arranged in series with the oil pump shaft 63, the parts required for driving can be minimized, and the side on which the generator 32 is mounted Since the pumps 61 and 62 for oil pressure feeding and oil recovery are arranged on the opposite side, the size of the engine 6 can be reduced while maintaining the right and left balance.

Although the preferred embodiment of the present invention has been described in the above embodiment, it is needless to say that the present invention is not limited to this.

[0049]

As described above, according to the first aspect of the present invention, the length of the crankshaft is reduced as compared with the case where the valve drive gear and / or the power takeoff gear is provided at the end of the crankshaft. As a result, the overall width of the engine can be reduced. According to the second aspect of the present invention,
The valve drive gear, the power transmission chain and the valve shaft gear engaged with the valve drive gear can be arranged at the center of the engine, and the right and left weight balance is improved. According to the third aspect of the present invention, the driven engine and the generator can be housed within the width of the crankshaft, and the entire engine can be made compact. In addition, the generator is a flywheel type, so there is no need for extra parts such as gears and pulleys as when using an alternator, and the mounting space can be made compact,
And the overall width of the engine can be kept to a minimum. According to the invention of claim 4, the oil pump can be arranged on the opposite side of the generator, and the right and left weight balance is improved. According to the invention of claim 5, the components required for driving can be minimized, and the pumps for oil pressure feeding and oil recovery are arranged on the side opposite to the side where the magnet rotor is mounted. Therefore, compactness can be achieved while maintaining the right and left balance of the engine.

According to the sixth aspect of the invention, when adjusting the tooth contact of the bevel gear, the installation position of the housing in which the ball bearing is installed with respect to the crankcase is simply adjusted by interposing a shim or the like. The position changes and the others are roller bearings, and the driven shaft is slidably supported in the axial direction, so the adjustment of the driven shaft only adjusts the driven axial position to adjust the bevel gear tooth contact. it can. Therefore, the tooth contact of the bevel gear can be adjusted without the necessity of disassembling the crankcase, so that the adjustment operation is extremely easy. According to the seventh aspect of the invention, if the position of the housing is adjusted, the position of the ball bearing can be adjusted. Therefore, when adjusting the tooth contact of the bevel gear, simply adjust the installation position of the housing in which the ball bearings are installed with respect to the crankcase by interposing a shim or the like, the position of the ball bearings changes, and the others are roller bearings. Since the output shaft is slidably supported in the axial position, the driven shaft position can be adjusted by simply adjusting the housing to adjust the contact of the bevel gear.

[Brief description of the drawings]

FIG. 1 is an overall side view of a watercraft according to an embodiment of the present invention.

FIG. 2 is a plan view of the watercraft.

FIG. 3 is an explanatory diagram showing an internal structure of an engine of the watercraft according to the first embodiment.

FIG. 4 is an explanatory diagram of an engine of the personal watercraft according to the second embodiment.

FIG. 5 is an example of a shim for adjusting the position of a housing.

FIG. 6 is an explanatory diagram of an internal structure of an engine according to a third embodiment.

FIG. 7 is an explanatory diagram of each gear such as a pump drive gear of the engine according to the third embodiment.

FIG. 8 is an explanatory diagram of an arrangement of each pump of the engine according to the third embodiment.

FIG. 9 is an explanatory view of an engine of a conventional watercraft.

FIG. 10 is an explanatory view of an engine of another conventional watercraft.

[Explanation of symbols]

Reference Signs List 6 engine 8 jet pump 9 crankcase 12 crankshaft 13 power change mechanism 17 impeller shaft 28 valve drive gear 29 power takeout gear 30 driven shaft 31 driven gear 32 flywheel type generator 33A, 33B input side bevel gear, output side bevel gear 34 output axis

────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Junzo Ueda 300 Takatsukacho, Hamamatsu-shi, Shizuoka Suzuki Co., Ltd. (56) References JP-A-8-53098 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B63B 35/73 F02B 67/04

Claims (7)

(57) [Claims] 1. A rotatable steering handle substantially at the upper center of a hull, and a long seat in the front-rear direction provided at a rear portion of the handle. Steps are provided on both left and right sides of the seat. A four-cycle multi-cylinder engine with a crankshaft placed horizontally in the direction perpendicular to the hull travel direction is mounted inside the hull, and the jet pump at the rear of the hull is operated via an impeller shaft parallel to the hull travel direction by driving the engine. A watercraft, wherein a valve drive gear for extracting valve drive force from a crankshaft and a power takeoff gear for extracting impeller shaft drive force are arranged on a crankshaft between cylinders at left and right ends. Planing boat engine structure. 2. The engine structure of a watercraft according to claim 1, wherein the valve drive gear is provided at a center of the crankshaft and at a center of the hull. 3. A power take-off gear is disposed in a cylinder adjacent to the center of the crankshaft, and a driven shaft driven by the power take-off gear is disposed behind the crankshaft. The engine structure of a watercraft according to claim 1 or 2, wherein a drive shaft is connected, and the generator is disposed behind the crankshaft and within the crankshaft width. 4. A power take-off gear is disposed in a cylinder adjacent to a center portion of a crankshaft, and a driven shaft driven by the power take-off gear is disposed behind the crankshaft. The engine structure of a watercraft according to any one of claims 1 to 3, wherein a drive shaft is connected, and an oil pump is provided on a side of the driven shaft opposite to a side where the generator is provided. 5. The engine of a watercraft according to claim 4, wherein the oil pump is provided with oil pumps and oil recovery pumps in series with the oil pump shaft. 6. A driven shaft and an output shaft for driving an impeller shaft are rotated at right angles by a bevel gear, and the driven shaft has a bearing structure in which one side of the driven shaft is supported by a ball bearing and the other side is supported by a roller bearing. The engine structure according to any one of claims 1 to 5, wherein the ball bearing is installed in a housing whose position in the driven axial direction can be adjusted with respect to the engine case. 7. The bearing structure of the output shaft, one side of which is supported by a ball bearing and the other side of which is supported by a roller bearing, wherein the ball bearing is installed in a housing whose position in the output shaft direction can be adjusted with respect to the engine case. The engine structure of a personal watercraft according to claim 6, wherein the engine structure is provided.