JPH09228850A - Four cycle engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set both vehicle width and height dimensions low, and try to make the size small by disposing three components, that is, a cam tensioner adjuster, a starter motor and an oil filter in this order from above while being arranged in one line as viewed from the side in front of an engine in the four cycle engine where a cylinder is inclined forward. SOLUTION: In the four cycle engine where one cylinder 5 located in front of a vehicle out of two cylinders 5 and 5, is inclined forward with respect to a crank case 4 mounted on to an motor bicycle, a cam tensioner adjuster 7 is mounted in the direction normal to the lower surface 5d of a cylinder 5 in such a way as to be located in the inside of the cylinder 5, and a starter motor 9 and an oil filter 11 are mounted while being faced to the front surface 4f of a crank case 4. And moreover, the oil filter 11 is lapped in the cam tensioner adjuster 7 in the right and left direction (vehicle width direction) however, it is so disposed in a place as not to interfere with the mounting of the cam tensioner adjuster 7.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a four-stroke engine. Specifically, it relates to a four-cycle engine in which at least a cylinder is inclined forward.

[0002]

2. Description of the Related Art There are a single-cylinder engine in which cylinders are tilted forward in order to reduce a vehicle height, or a V-type engine in which a plurality of cylinders are distributed in a front-rear direction and tilted. Some of these engines have a starter motor and an oil filter arranged in the vehicle width direction on the front surface thereof, but in this case, the vehicle width dimension becomes large and it is difficult to meet the demand for downsizing. Therefore, it is conceivable to arrange the starter motor and the oil filter in the height direction of the engine.

On the other hand, in the case of a four-cycle engine, the cylinder is equipped with a cam tensioner adjuster, which is a component of the valve opening / closing mechanism. However, as shown in FIG. 3, when the degree of inclination of the cylinder a is large. When the cam tensioner adjuster b is arranged in the height direction of the engine e together with the starter motor c and the oil filter d on the front surface of the forward tilting cylinder, the cam tensioner adjuster b
However, it is conceivable that the tool f required for assembling the cam tensioner adjuster may interfere with the starter motor c or the oil filter d. Especially starter motor c
Is closer to the cam tensioner adjuster b than the oil filter d, the cam tensioner adjuster b
In addition, it is more likely to interfere.

In order to avoid the interference, the cylinder a
There is a dilemma in that the degree of forward lean of the vehicle must be set low, and as a result, the intended purpose of lowering the vehicle height cannot be achieved.

Therefore, in an engine in which the starter motor and the oil filter are arranged in the height direction of the engine, the vehicle height is set low and the interference of the cam tensioner adjuster or its mounting tool, especially the starter motor, is prevented. It was desired to provide a new technology that can do this.

Therefore, it has been desired to provide a four-cycle engine which can set the vehicle height low and prevent the cam tensioner adjuster or its installation tool from interfering with the starter motor.

[0007]

SUMMARY OF THE INVENTION The present invention has been invented in view of the above circumstances, and an object of the present invention is to set a vehicle width dimension and a vehicle height dimension to be low and to provide a cam tensioner adjuster. Or to provide a four-cycle engine that can prevent the interference of the installation tool with the starter motor or the oil filter and further retract the crankcase more than necessary or reduce the volume of the crankcase. Especially.

[0008]

The present inventor has taken the following means in order to solve the above problems. That is, the four-cycle engine of the present invention has its cylinder tilted forward. Then, the three parts of the cam tensioner adjuster, the starter motor and the oil filter are arranged on the front surface of this engine in this order from the top and in a row in the height direction of the engine so that they do not interfere with each other. did.

The starter motor may be located below the mating surface of the cylinder and the crankcase and on the engine center side.

Therefore, according to the present invention, the three parts of the cam tensioner adjuster, the starter motor and the oil filter are arranged on the front surface of the engine in this order from the top and the height of the engine is arranged such that they do not interfere with each other. Since they are arranged in a row from the side, the cam tensioner adjuster should be set so that the starter motor and oil filter do not exist in the installation direction of the cam tensioner adjuster on the assumption that this condition is satisfied. The presence of the starter motor and oil filter can be kept out of the way when installing the.

More specifically, the cam tensioner adjuster is
Since it is arranged on the lower surface of the cylinder which is tilted forward for structural reasons, the mounting direction is perpendicular to the lower surface of the cylinder. In other words, the mounting direction of the cam tensioner adjuster should be expanded upward from the vertical position extending downward from the mounting position of the cam tensioner adjuster on the cylinder, at an angle according to the inclination angle of the cylinder. It is the direction in which the virtual axis extends.

On the other hand, the starter motor and the oil filter are located in front of the crankcase. For this reason, the mounting direction of both is the vehicle front-back direction.

Therefore, the cam tensioner adjuster,
The three parts of the starter motor and the oil filter are arranged in this order from the top and in a line in the height direction of the engine as viewed from the vehicle side so that they are in a positional relationship where they do not interfere with each other. That is, if the three parts are arranged in the vertical direction and the mounting direction of the cam tensioner adjuster is a direction in which a virtual axis that expands upward at an angle corresponding to the inclination angle of the cylinder with respect to the vertical line extends, Since the starter motor and oil filter are not located on the shaft,
It is possible to prevent interference of the three parts.

Further, if the starter motor is set so as not to exceed the mating surface of the cylinder with respect to the crankcase on the premise of the above conditions, it is further useful for preventing interference.

Further, since the starter motor is located below the mating surface of the cylinder and the crankcase and on the engine center side, the engine can be made compact accordingly.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail based on the illustrated embodiments with reference to the drawings. FIG. 1 is a right side view of a motorcycle 3 in which a four-cycle engine 1 according to the present invention is adopted, and FIG. 2 is an enlarged view of a main part of FIG.

The motorcycle 3 is equipped with a four-cycle engine 1 in which one of the two cylinders 5, 5, which is located in front of the vehicle with respect to the crankcase 4, is inclined forward. On the front of this four-cycle engine 1,
The three parts of the cam tensioner adjuster 7, the starter motor 9 and the oil filter 11 are arranged in this order from the top and in a row in the height direction of the four-cycle engine 1 so that they are in a positional relationship where they do not interfere with each other. It is arranged.

Specifically, the cam tensioner adjuster 7
Is perpendicular to the lower surface 5d of the cylinder 5 and
It is installed so that it is located inside the. In other words, the mounting direction of the cam tensioner adjuster 7 is upward at the angle A corresponding to the inclination angle of the cylinder 5 with respect to the vertical line 13 extending downward from the mounting position of the cam tensioner adjuster 7 on the cylinder 5. In other words, it is the direction in which the virtual axis 15 that spreads counterclockwise at the angle A in FIG. 2 extends.

Starter motor 9 and oil filter 11
Is located on the front surface 4f of the crankcase 4. Therefore, the mounting direction of both 9 and 11 is the front-back direction of the vehicle.

The oil filter 11 is arranged at a position that wraps the cam tensioner adjuster 7 in the left-right direction (vehicle width direction) but does not hinder the attachment of the cam tensioner adjuster 7.

However, in such a four-cycle engine 1, the three parts of the cam tensioner adjuster 7, the starter motor 9 and the oil filter 11 are arranged in this order from the top and in a positional relationship where they do not interfere with each other. The four-cycle engine 1 is arranged in a row in the height direction as viewed from the side of the vehicle. That is, the three parts are arranged in the direction in which the vertical line 13 extends, and the mounting direction of the cam tensioner adjuster 7 with respect to the vertical line 13 is the cylinder 5
Since the imaginary shaft 15 that expands upward at an angle A corresponding to the inclination angle of the extension direction is set to extend, the starter motor 9 and the oil filter 11 are not located on the imaginary shaft 15, resulting in three Interference of parts can be prevented.

Further, the starter motor 9 is, for example, below the mating surface 5a and toward the center of the four-cycle engine 1 (the center of the crankshaft 4s) so as not to exceed the mating surface 5a of the cylinder 5 with respect to the crankcase 4. If it is located, it further helps prevent interference.

If the starter motor 9 is positioned within a triangular area S formed by the virtual shaft 17 extending in the mounting direction of the oil filter 11, the vertical line 13, and the virtual shaft 15 of the cam tensioner adjuster 7. The space between the cam tensioner adjuster 7 and the oil filter 11 can be effectively used.

[0024]

According to the present invention, even in an engine having a cam tensioner adjuster, a starter motor and an oil filter arranged in front of the engine having a forward tilt cylinder, the vehicle width and vehicle height can be set low, and It is possible to prevent the interference of the cam tensioner adjuster or its installation tool with the starter motor or the oil filter.

[Brief description of drawings]

FIG. 1 is a right side view of a motorcycle in which a four-cycle engine according to the present invention is adopted.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is a diagram for explaining a conventional technique.

[Explanation of symbols]

 1 Four-cycle engine 4 Crankcase 4s Engine center side 5 Cylinder 5a Mating surface 7 Cam tensioner adjuster 9 Starter motor 11 Oil filter

Claims (2)

[Claims] 1. A four-cycle engine having a cylinder tilted forward, in which three parts of a cam tensioner adjuster, a starter motor and an oil filter are placed on the front surface of the engine in this order from the top and they do not interfere with each other. A four-cycle engine, which is arranged in a row in the height direction of the engine as seen from the side. 2. The four-cycle engine according to claim 1, wherein the starter motor is located below the mating surface of the cylinder and the crankcase and on the engine center side.