JPH09287467A - Supercharging engine-mounted vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the flow passage resistance of compressed air so as to improve filling efficiency by arranging a crank chamber in which a connecting rod is arranged and a pressure intake passage for supplying compressed new air from the crank chamber into a combustion chamber along a cylinder axial line in the top view of body. SOLUTION: In a scooter type motorcycle, an unit swing type engine unit 11 is mounted, the unit 11 comprises an engine main body 12 and a rear wheel transferring device 13. In the engine main body 12, its cylinder shaft is forward slantly arranged from a vertical direction, a connecting rod supercharging type supercharger 50 is arranged, and pressurized air is supplied from a pressure intake pipe 53 into a carburetor 54 for composing a fuel supplying device N. At this time, a crank chamber 63 in which a connecting rod is arranged and a pressure intake passage for supplying compressed new air from the crank chamber 63 into a combustion chamber 65 are arranged on a cylinder axial direction in the top view of a body, and thereby, it is possible to reduce bending of an intake passage so as to reduce the flow passage resistance of compressed air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a supercharged engine-equipped vehicle equipped with a supercharger.

[0002]

2. Description of the Related Art In recent years, for the purpose of improving engine output, for example, supercharging equipped with a connecting rod supercharging mechanism for compressing air sucked into a crank chamber by swinging the connecting rod and supplying the compressed air to a combustion chamber. A device has been proposed (see, for example, Japanese Patent Laid-Open No. 6-93869). A supercharging device including the connecting rod supercharging mechanism and a piston supercharging mechanism that compresses the air sucked into the crank chamber by the reciprocating movement of the piston is called a crank chamber supercharging device.

[0003]

When an engine equipped with such a crank chamber supercharging device is mounted on a vehicle, in particular, the air sucked into the crank chamber is compressed and supplied to the combustion chamber. It is necessary to make the resistance of the flow path as small as possible to ensure smooth supply. For example, if the flow resistance of the compressed air is large, the charging efficiency may be reduced, and in some cases, the engine performance may be adversely affected.

The present invention has been made in view of the above circumstances, and provides a vehicle equipped with a supercharged engine capable of reducing the flow path resistance of compressed air to improve the charging efficiency and avoiding adverse effects on engine performance. The purpose is to do.

[0005]

In order to solve the above-mentioned problems and to achieve the object, the invention according to claim 1 uses fresh air pressurized by a supercharger through a pressurizing intake passage and an intake valve. In a vehicle equipped with a supercharged engine that leads to a combustion chamber, a crank chamber in which a connecting rod is arranged and a pressurized intake passage for sending compressed fresh air from the crank chamber to the combustion chamber are arranged along the cylinder axis in a top view of the vehicle body. It is characterized by being.

The crank chamber and the pressurized intake passage are arranged along the cylinder axis in a top view of the vehicle body, the intake passage is less bent, the flow resistance of the compressed air is reduced, and the charging efficiency is improved. It is possible to avoid adverse effects on performance.

According to the second aspect of the present invention, the intake ports are arranged in the cylinder head at the ends of the intake ports on the combustion chamber side, and the intake ports are arranged along the cylinder axis in a top view of the vehicle body. It is characterized by being.

An intake valve is arranged in the cylinder head at the end of the intake port on the side of the combustion chamber of the intake port, and the intake port is arranged along the cylinder axis in a top view of the vehicle body. As a result, the flow resistance of the compressed air is reduced, the filling efficiency is improved, and adverse effects on engine performance can be avoided.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A vehicle equipped with a supercharged engine of the present invention will be described below with reference to the drawings.

First, a scooter type motorcycle in which a vehicle equipped with a supercharged engine is adopted will be described. FIG. 1 is a schematic configuration diagram of a scooter type motorcycle. In the figure, 1 is a scooter type motorcycle to which the present invention is applied, and a body frame 2 of the scooter type motorcycle is of an underbone type, and an upper end of a main frame 2b having a substantially L shape in a side view is connected to a head pipe 2a. The front end of a pair of left and right side frames 2c is connected to the lower end of the main frame 2b, both side frames 2c are raised upward, and further extended rearward. Further, the head pipe 2a has a front wheel 3 at the lower end.
A front fork 4 that pivotally supports the front fork 4 is pivotally supported to the left and right, and a steering handle 5 is fixed to the upper end of the front fork 4.

A steering wheel cover 6 is provided around the steering handlebar 5.
The periphery of the head pipe 2a is covered with a front cover 7 having a two-part structure including a front cover 7a and a rear cover 7b. Further, a footboard 8 forming a footrest portion is arranged at a connecting portion between the main frame 2b and the side frame 2c, and side covers 9 are arranged on the left and right sides of the side frame 2c. A seat 10 is arranged above the side cover 9.

A unit swing type engine unit 11 is mounted near the upper and lower bent portions of the left and right side frames 2c. The engine unit 11 includes a pivot shaft 32a horizontally arranged in the left-right direction (see FIGS. 5 and 7).
The rear wheel transmission includes an engine main body 12 that is swingably supported around and extends substantially horizontally forward, and a rear wheel transmission 13 integrally connected to a left side portion of the engine main body 12 so as to extend rearward. A rear wheel 14 is pivotally supported at the rear end portion of 13. The rear end of the rear wheel transmission 13 is supported by the side frame 2c via the rear suspension 15.

The forward leaning of the engine described here means that the engine body 12 is located in front of the pivot shaft 32a,
It means that the engine body 12 extends forward of a vertical plane passing through the crankshaft 64. Here, another embodiment of the forward leaning of the engine is shown in the external view of the main part of FIG. The cylinder axis of the engine body 12 is inclined forward from the vertical direction. Details of the parts indicated by the numbers in the figure will be described below. The swing engine unit 11 is rotatable around the pivot shaft 32a.

Next, the rear wheel drive system of the unit swing type engine unit 11 will be described. FIG. 2 is a sectional view of a rear wheel drive system in which the rear wheels rotate in the same direction as the engine rotation direction. Unit swing type engine unit 11
The rear wheel transmission 13 extends rearward from one side of the engine body 12. Transmission case 20 of the rear wheel transmission 13
The power transmission mechanism 21 housed therein includes a V-belt automatic transmission device 22, a centrifugal clutch 23, an output shaft 26, and a gear train 24.

The V-belt automatic transmission 22 has an input shaft 22.
a, front sheave 22b, V belt 22c, rear sheave 2
2d and the output shaft 22e. Power from the engine body 12 is transmitted to the input shaft 22a, further automatically shifted from the front sheave 22b via the V belt 22c by the rear sheave 22d, and transmitted from the output shaft 22e to the centrifugal clutch 23.

The centrifugal clutch 23 is provided in the inner housing 2
3a, an outer housing 23b, a centrifugal cam 23c and the like. Output shaft 22 of V-belt automatic transmission 22
The power from e is transmitted to the inner housing 23a,
It is transmitted to the outer housing 23b from the centrifugal cam 23c which opens outward by centrifugal force, and is further transmitted to the output shaft 26.

The gear train 24 comprises a first gear 24a, a second gear 24b, a third gear 24c and a fourth gear 24d. The first gear 24a provided on the output shaft 26 is decelerated by the second gear 24b, the third gear 24c, and the fourth gear 24d and transmitted to the rear axle 25. By this gear train 24, the same direction of rotation of the engine is achieved. The rear wheel 14 is adapted to rotate. That is, the rotation direction of the rear wheel 14 and the rotation direction of the engine when the vehicle body moves forward match. The rear axle 25 is coaxially separated from the output shaft 26.

FIG. 3 is a sectional view of another embodiment of the rear wheel drive system in which the rear wheels rotate in the same direction as the engine rotation direction.
The rear wheel transmission 13 of the unit swing type engine unit 11 includes a power transmission mechanism 21 housed in a transmission case 20 of the rear wheel transmission 13 as in the above-described embodiment, a V-belt automatic transmission 22 and a centrifugal clutch. 23 and the output shaft 2
6 and gear train 24, centrifugal clutch 23
And the configuration of the gear train 24 are different.

The centrifugal clutch 23 is provided in the inner housing 2
3f, outer housing 23g, friction plates 23h, 23i
And a centrifugal roller 23j and the like. The power from the V-belt automatic transmission 22 is transmitted to the outer housing 23g of the centrifugal clutch 23, and the centrifugal roller 23j moves outward by centrifugal force, so that the inner housing 23f and the outer housing 23g move only in the axial direction. The friction plates 23h and 23i are engaged as much as possible to transmit power to the inner housing 23f and further to the output shaft 26.

The gear train 24 is composed of a first gear 24f, a second gear 24g, a third gear 24h, a fourth gear 24i and the like. The first gear 24f provided on the output shaft 26 is decelerated by the second gear 24g, the third gear 24h, and the fourth gear 24i and transmitted to the rear axle 25, and by this gear train 24, the same direction as the engine rotation direction is obtained. The rear wheel 14 is adapted to rotate. The rear axle 25 is located rearward of the output shaft 26.

Next, a schematic structure of the unit swing type engine unit 11 of the first embodiment will be described. 5 and 6 show a first embodiment of a unit swing type engine unit equipped with an air-cooled 4-cycle supercharged engine, FIG. 5 is a side view of the unit swing type engine unit, and FIG. 6 is a unit swing type. It is a top view of a rotary engine unit.

A unit swing type engine unit 11 is mounted near the upper and lower bent portions of the left and right side frames 2c. In this engine unit 11, a bracket 30 provided on the front side of the transmission case 20 of the rear wheel transmission 13 and a bracket 31 of the side frame 2c are supported via a link 32, and provided on the rear side of the transmission case 20. The bracket 33 and the bracket 34 of the side frame 2c are supported via the rear suspension 15, and the engine unit 11 includes the link 32 and the bracket 3.
It is rotatable about a pivot shaft 32a between the first and second gears. Further, an elastic bush (not shown) is interposed between the bracket 31 and the link 32, and the elastic bush holds the link 32 so that the link 32 is not pivotally displaced about the support shaft 32b.

A stopper 35 for restricting the upward swing of the rear wheel transmission 13 is provided. This allows
When a vehicle body is held while preventing a fall by standing a stand 11a that is rotatably supported by the engine unit 11, the engine unit 11 is pushed up and the link 32 rotates upward, but a part of the link 32 stops. It abuts 35 and prevents interference with other parts of the engine body 12.

The engine body 12 is of a forced air-cooled, 4-cycle, single-cylinder type, and has a structure in which a cylinder block 41 and a cylinder head 42 are connected to a crankcase 40. Cylinder bore 60 of cylinder block 41
While the piston 61 is slidably inserted and arranged in the inside,
The piston 61 is connected by a connecting rod 62 to a crankshaft 64 arranged in a crank chamber 63.

A forced cooling fan 43 for supplying cooling air is mounted on the engine body 12, and cooling fins 44 for increasing the heat radiation area are provided on the cylinder block 41. Although not shown, the cylinder head 42 also has cooling fins. A front air intake 45 is provided in the side cover 9 below the seat 10, and the front air intake 45 is composed of a slit 45a and a louver 45b, and the traveling wind is guided toward the engine body 12 from the front side. In addition, the lower cover 46 below the footboard 8
Is provided with a lower air intake 47, and the lower air intake 47 is composed of a slit 47a and a louver 47b, and the traveling wind is guided toward the engine body 12 from the lower side.

The engine body 12 is provided with a connecting rod supercharging device 50. The air filtered by the air cleaner 51 is sucked into the crank chamber 63 through the suction pipe 52 from the crank chamber suction port 40a below the crankcase 40. The air pressurized by the connecting rod supercharging mechanism in the engine body 12 constitutes the fuel supply device N from the crank chamber discharge port 40b on the upper side of the crankcase 40 through the pressurized intake pipe 53 which constitutes the pressurized intake passage. It is sent to the carburetor 54. In the carburetor 54, fuel is introduced from a suction port 42 a on the upper side of the cylinder head 42 into a combustion chamber 65 via a pressurized intake pipe 55.
Is supplied to. Reference numeral 407 in the drawing is a throttle cable for controlling the carburetor 54.

Since the engine unit 11 is displaced during traveling, the intake pipe 52 between the air cleaner 51 fixed to the vehicle body and the engine body 12 is provided with a bendable portion in a part or all of the portion. Further, the carburetor 54 is fixed to the cylinder block 41 or the cylinder head 42 via a vibration damping rubber mount (not shown).
Therefore, similarly, the bendable portion is arranged in a part or all of the pressure intake pipes 53, 55. Then, the engine unit 11 is displaced by the carburetor 5 as it is displaced during traveling.
4, the pressurized intake pipes 53, 55 and the exhaust pipe 56 described below are displaced substantially integrally with the engine body 12.

Exhaust outlet 42b below the cylinder head 42
Is connected to an exhaust pipe 56, the exhaust pipe 56 extends rearward on the right side of the engine unit 11, and a muffler 57 is connected to a rear end portion thereof.

The engine body 12 has a lubricating device 4
The lubrication device 460 is provided with 60 to suck and pressurize the 2-cycle lubricating oil, and the pressurized lubricating oil is supplied to each bearing around the crankshaft 64, the piston sliding portion of the cylinder block 41, and the like. Four-cycle oil is circulated and supplied to the valve train in the cylinder head 42 by a lubricating device (not shown). The lubrication will be described in detail in the description of FIG.

The crank chamber 63, the pressurizing intake pipe 53, and the carburetor 54 are arranged on the same line along the cylinder axis L2 in a top view of the vehicle body, and the intake passage after pressurizing in the crank chamber 63 is bent. The flow resistance is reduced, the filling efficiency is improved, and the engine performance is improved. It should be noted that, in this embodiment, in addition to the structure described in the claims, many unique effects can be obtained by many unique structures.
These features are described below.

First, the air cleaner 51 is arranged at a position rearward of the front air intake 45 of the side cover 9, and the suction pipe 52 is connected to the cylinder head 42 and the cylinder block 4.
1 is connected to the lower side of the crankcase 40 along the left side of 1, and is sucked into the crank chamber 63 from the lower side. The air cleaner 51 is disposed on the vehicle front side of the crank chamber 63 as shown in FIG. 5 and on the rear wheel transmission 13 side as shown in FIG. 6, and is capable of sucking cold fresh air, so that the charging efficiency is improved.
Improves engine performance. Further, the traveling wind is not obstructed by the air cleaner 51, and the cold air of the traveling wind passes through the pressurized intake pipe 53, the carburetor 54, and the pressurized intake pipe through which fresh air pressurized and heated in the crankcase 40 passes. Since it hits 55, the cooling performance is good, and the engine performance and durability are improved by the increase of the filling efficiency. Further, the cooling properties of the exhaust pipe 56 and the generator 250 are also increased, and the durability is improved.

Secondly, the engine body 12 is located in front of the bracket 31 which is a support portion for the vehicle body, so that the cylinder C is tilted forward. Then, the crankshaft 64 is arranged horizontally, and the crank chamber suction port 40a is connected to the crankshaft 6.
4, the crank chamber discharge port 40b is disposed above the crank shaft 64. Therefore, the lubricating oil supplied to the sliding portion of the piston 61 and the crankshaft 64 hardly enters the combustion chamber 65 and stays in the crankcase 40, and the sliding portion of the piston 61, the bearings of the large and small ends of the connecting rod 62, and the crankshaft. Since it contributes to lubrication of the lubrication required portion around 64, the supply of lubricating oil can be reduced correspondingly, and the consumption of lubricating oil can be reduced.

Thirdly, the carburetor 54 is disposed above the engine axis L1, the carburetor 54 is located on the vehicle body frame 2 side, and the carburetor 54 is prevented from being damaged by stone hitting during traveling. .

Fourthly, the carburetor 54 which constitutes the fuel supply device N is disposed above the cylinder, and the fuel supplied from the carburetor 54 adheres to the pressurized intake pipe 55 and becomes a solid. Supply to the combustion chamber 65 is prevented, fuel can be supplied smoothly, and exhaust gas H
It is possible to reduce C and avoid adverse effects on engine performance.

Fifth, as shown in FIG. 5, the crank chamber discharge port 40b and the intake side of the cylinder head 42 are the same when viewed from the engine axis L1, and the pressurizing intake pipe 53 can be shortened. The flow path resistance can be reduced, the filling efficiency is improved, and the engine performance is improved.

Sixth, the engine main body 12 is provided with an exhaust outlet 42b on the lower side of the engine, and the exhaust pipe 56 is at a position where it is easy to come into contact with the outside air such as traveling wind, so that the cooling performance is good and there is a heat effect. Is reduced and the durability of the exhaust pipe 56 is improved,
Moreover, the exhaust pressure is reduced, the exhaust efficiency is improved, and the engine performance is improved. In addition, the exhaust pipe 56 of the heavy object is located at the lower position of the vehicle body, and the running stability is good. Further, the exhaust pipe 56 is
Although it is easily corroded by the moisture of fuel and the moisture of combustion, the exhaust pipe is located outside the vehicle body and replacement work is easy.

7 and 8 show a second embodiment of a unit swing type engine unit equipped with a water-cooled partially air-cooled 4-cycle supercharged engine, and FIG. 7 is a side view of the unit swing type engine unit. 8 is a plan view of a unit swing type engine unit. In the engine unit 11 of this embodiment, the crank chamber 63, the pressurized intake pipe 53, and the carburetor 54 are the same as the cylinder axis in a top view of the vehicle body, except that the air cooling type shown in FIGS. 5 and 6 is replaced with a water cooling type. Since they are arranged on the same line along L2, and the bend of the intake passage after pressurization in the crank chamber 63 is configured to be small, the same reference numerals are given and description thereof will be omitted.

A radiator 70 is arranged in parallel with the air cleaner 51 at a position rearward of the front air intake 45 of the side cover 9. The cooling water that has cooled the engine body 12 is returned to the radiator 70 via a return pipe 71,
It is cooled by the radiator 70 and sent again to the engine body 12 via the feed pipe 72 to cool the cooling water.
2. It is circulated to a cooling water jacket (not shown) in the cylinder head 42 for cooling. Air-cooling fins are attached to the outer circumference of the cylinder 41 for air-cooling. It should be noted that this embodiment also has many features described as the first to sixth in the description of the first embodiment other than the configuration described in the claims.

With regard to the first feature, the air cleaner 51 can be arranged on the left side of the engine body 12 and on the front side of the rear wheel transmission 13 as shown in FIG. The traveling air is not obstructed by the air cleaner 51 and passes between the radiator 70 and the cold air of the traveling air hits the pressurized intake pipe 53, the carburetor 54 and the pressurized intake pipe 55, so that the cooling performance is good. , Engine performance and durability are improved. The exhaust pipe 56, the generator 250, and the like are cooled by the traveling wind passing through the radiator 70.

9 and 10 show a third embodiment of a unit swing type engine unit equipped with an air-cooled 4-cycle supercharged engine. FIG. 9 is a side view of the unit swing type engine unit, and FIG. 10 is a unit. It is a top view of a swing type engine unit. In the engine unit 11 of this embodiment, the crank chamber 63, the pressurized intake pipe 53, and the carburetor 54 are arranged on the same line along the cylinder axis L2 in a top view of the vehicle body, as in the air-cooled type shown in FIGS. Since the bend of the intake passage after pressurization in the crank chamber 63 is small, the same reference numerals are given and the description thereof is omitted, but the arrangement position of the air cleaner 51 is different.

The air cleaner 51 is arranged rearward of the crankshaft 64 in the vehicle body and above the rear wheel transmission 13, and in a space above the rear wheel transmission 13. The suction pipe 52 penetrates the transmission case 20 of the rear wheel transmission 13 from the upper side to the lower side.
The space inside the vehicle is used more. It should be noted that in this embodiment also, in addition to the configuration described in the claims, the first
It has many features described as the first to sixth described in the description of the embodiments. In particular, since the air cleaner 51 is not arranged in the front upper part of the engine body 12, the pressurized intake pipes 53, 55 and the like can be cooled more reliably and the engine performance can be improved.

11 and 12 show a fourth embodiment of a unit swing type engine unit equipped with a water-cooled partially air-cooled 4-cycle supercharged engine, and FIG. 11 is a side view of the unit swing type engine unit. 12 is a plan view of the unit swing type engine unit. In the engine unit 11 of this embodiment, the crank chamber 63, the pressurized intake pipe 53, and the carburetor 54 are arranged on the same line along the cylinder axis L2 in a top view of the vehicle body, as in the water-cooled type shown in FIGS. Since the bend of the intake passage after pressurization in the crank chamber 63 is small, the same reference numerals are given and the description thereof is omitted, but the arrangement position of the air cleaner 51 is different.

The air cleaner 51 is arranged rearward of the crankshaft 64 in the vehicle body and above the rear wheel transmission 13, and in a space above the rear wheel transmission 13. The suction pipe 52 penetrates the transmission case 20 of the rear wheel transmission 13 from the upper side to the lower side.
The space inside the vehicle is used more. Here, the air cleaner 51 is fixed to the bracket 20a of the transmission case 20, and integrally swings when the engine unit 11 swings.

It should be noted that this embodiment also has many features described as the first to sixth in the description of the first embodiment, in addition to the structure described in the claims. In particular, the exhaust pipe 56, the generator 250, etc. are the radiator 70.
It is the same as the second embodiment in that it can be cooled by the traveling wind that has passed through. In addition, when the position of the radiator 70 is arranged at the position of the air cleaner 51 shown in the first embodiment,
The exhaust pipe 56, the generator 250, and the like can be cooled by colder running air, and performance or durability can be improved.

13 and 14 show a fifth embodiment of a unit swing type engine unit equipped with an air-cooled 4-cycle supercharged engine. FIG. 13 is a side view of the unit swing type engine unit, and FIG. 14 is a unit. It is a top view of a swing type engine unit. The engine unit 11 of this embodiment has a crank chamber 63, a pressurized intake pipe 53, and a carburetor 5 as in the air-cooled type shown in FIGS. 9 and 10.
4 are arranged on the same line along the cylinder axis L2 in a top view of the vehicle body, and since the bend of the intake passage after pressurization in the crank chamber 63 is configured to be small, the same reference numerals are given and description thereof is omitted. However, the arrangement position of the air cleaner 51 is different.

The air cleaner 51 is arranged behind the crankshaft 64 in the vehicle body and above the rear wheel transmission 13, and the suction pipe 52 connected to the air cleaner 51 is flat and connected to the upper rear part of the crankcase 40. Has been done. A suction passage 40g penetrating in the vertical direction is formed behind the cam chain 48 in the crankcase 40 and laterally of the crank chamber 63, and opens into a suction passage 135 described below. The air cleaner 51 is arranged in the space above the rear wheel transmission 13 and is fixed to the bracket 20 a of the transmission case 20.

Next, the supercharged engine applied to each of the embodiments will be described in detail with reference to FIGS. 15 to 17.
15 is a sectional view of a water-cooled supercharged engine, and FIG. 16 is FIG.
FIG. 17 is a sectional view taken along line XVI-XVI (however, the cooling system is shown as an air-cooled supercharged engine unlike the engine shown in FIG. 15), and FIG. 17 is a sectional view taken along line XVII-XVII in FIG. .

In the figure, reference numeral 100 designates a crankshaft horizontally placed 4
This is a cycle single cylinder crank chamber supercharged engine, and a cylinder block 41 is connected to the mating surface of a crankcase 40 of this engine 100.
A cylinder head 42 is connected to the mating surface 1. A concave portion 42c forming a combustion chamber 65 is provided in a portion of the mating surface of the cylinder head 42 facing the cylinder bore 60,
A spark plug 200 is inserted in the recess 42c.
In the water-cooled supercharged engine of FIG. 15 the cooling water jackets are arranged in both the cylinder block 41 and the cylinder head 42, but in the air-cooled supercharged engine of FIG. 16 both the cylinder block 41 and the cylinder head 42 are arranged. A plurality of air cooling fins are arranged on the outer periphery of each. Note that FIG. 7, FIG. 8, FIG. 11, FIG.
In each of the embodiments shown in FIGS. 14, 18 and 19, 24 and 25, 28 and 29, and 32 and 33, the cylinder head 41 is a water-cooled partially air-cooled supercharged engine for air cooling. Although mounted, in these embodiments, a water-cooled supercharged engine in which the cylinder head 42 and the cylinder block 41 are water-cooled may be mounted.

An intake port 105 and an exhaust port 106 are opened in the recess 42c of the cylinder head 42, the intake port 105 is led out to the upper wall side of the cylinder head 42, and the exhaust port 106 is led out to the lower wall side. There is. Further, an intake valve 107 is arranged in the combustion chamber opening of the intake port 105, and an exhaust valve 108 is arranged in the combustion chamber opening of the exhaust port 106 so that the respective openings can be opened and closed. The intake valve 107 and the exhaust valve 108 are valves. It is biased in the closing direction by a spring 109.

An intake valve 107 is provided on the cylinder head 42.
Also, a cam shaft 110 as a valve mechanism that opens and closes the exhaust valve 108 is arranged in a direction perpendicular to the plane of the drawing. A driven sprocket 201 is provided at one end of the cam shaft 110, and is connected to a drive sprocket 113 connected to the crank shaft 64 via a cam chain 48, and the cam shaft 110 is decelerated to half the rotation speed of the crank shaft 64. ing. A pair of rocker shafts 111 extending in parallel with the cam shaft 110 are arranged on the upper and lower sides of the cam shaft 110, and rocker arms 112 are swingably mounted on the rocker shafts 111. One end of the rocker arm 112 has a camshaft 1
The cam nose 10 is in contact with the other end of the intake valve 107 and the exhaust valve 108.

Cylinder bore 60 of cylinder block 41
A piston 61 is slidably inserted therein.
With the piston 61 as a boundary, the crank chamber 63 is provided by the cylinder bore 60 and the crankcase 40 on the side opposite to the combustion chamber 65.
Are formed. A small end portion 62a of a connecting rod 62 is connected to the piston 61 to a piston pin 66 via a bearing 67, and a large end portion 62b of the connecting rod 62 is connected to a crank pin 68 of a crankshaft 64 via a bearing 69. There is.

The crankshaft 64 is housed in the crank chamber 63, and a pair of disk-shaped crank webs 124 are connected by crank pins 68, and a journal 125 is formed integrally with each crank web 124. And the journal portion 125 is the journal bearing 12
It is supported by the crankcase 40 via 6. Further, the journal portion 125 projects outside the crankcase 40, and the generator 250 is mounted on one of the projecting portions. In addition, 127 on both sides of the crank chamber 63
Reference numerals a and 127b are oil seals.

The left and right inner side walls 40c of the crankcase 40 orthogonal to the crankshaft 64 are flush with the notches 41b formed in the upper and lower portions of the fitting portion 41a of the cylinder block 41 to the crankcase 40 in the figure. The left and right inner side walls 40c and the notches 41b are configured such that the left and right side surfaces 62c of the connecting rod 62 can be moved while facing each other with a minute gap therebetween, or they are in sliding contact with each other and are in contact with each other. The outer peripheral surface of the large end portion 62b of the connecting rod 62 is movable with respect to each other with a very small gap or is in contact with each other on the arcuate inner peripheral wall 40d formed so as to surround the crankshaft 64 of. Are in sliding contact with each other. Also, the left and right inner side walls 40c of the crankcase 40
Has a circular recess 40e into which each crank web 124 is inserted and arranged, and a slight gap is provided between the circular recess 40e and the crank web 124. Then, the connecting rod side wall 124 of the crank web 124
Both a and the left and right side surfaces 62c of the connecting rod 62 can be moved while facing each other with a minute gap therebetween, or are in contact with and are in sliding contact with each other. A ring 300 is fixedly arranged on the crankcase 40 at each of the mouths of the left and right circular recesses 40e, and the ring 300 comes into contact with the outer periphery of the protrusion of the crank web 124 to make sliding contact or almost zero.
They are facing each other with a gap of. The ring 300 is made of a material such as plastic, rubber or carbon. Even if the ring 300 has a slightly smaller inner circumference, the ring 300 may be worn or deformed when the outer circumference of the ridge of the crank web 124 comes into sliding contact with the crank web l2, even if the accuracy is poor.
It is possible to make the gap between the outer circumference of the ridge of No. 4 and 0.

Further, the skirt portion of the piston 61 is provided with a substantially triangular recess 61a.
The portion facing the outer periphery of the skirt is a notch 61b. The small end portion 62a of the connecting rod 62 is placed in the recess 61a.
Is inserted and arranged. Is it possible to move the outer peripheral surface of the small end portion 62a of the connecting rod 62 on the inner peripheral surface of the recess 61a, and the left and right side surfaces 62c on the left and right side surfaces 61c of the recess 61a with a minute gap therebetween while facing each other? , Are in sliding contact with each other.

With the above structure, the portion surrounded by the crank chamber 63, the crank web 124 and the piston 61 is a connecting rod accommodating chamber. At the crank angle except when the piston 61 is located near the top dead center, the connecting rod 62 is at least one of the upper and lower crankcases 40.
The connecting rod accommodating chamber is divided into a suction chamber A and a compression chamber B by a connecting rod 62 by fitting in the left and right inner side walls 40c or the notch 41b of the cylinder block 41. Further, when the piston 61 is located at the top dead center, the connecting rod 62 and the left and right inner side walls 40c are not fitted, but since the skirt end of the piston 61 almost coincides with the end of the cylinder bore 60, the suction chamber by the connecting rod 62. The division between A and the compression chamber B is maintained. In this way, as the crankshaft 64 rotates counterclockwise from the state where the piston 61 is located at the top dead center, as shown in FIG. By moving to the position, the volume of the suction chamber A increases and air is sucked in, and the volume of the compression chamber B decreases, so that the air sucked in the previous stroke is compressed. . Such a structure is described in detail in the above-mentioned Japanese Patent Application Laid-Open No. Hei 6-93869.

The lower surface of the crankcase 40 is integrally formed with a suction passage 135 communicating with the suction chamber A and opening downward. A crank chamber suction port 40a is formed on the front wall surface so as to communicate with the suction passage 135. The crank chamber suction port 40a is connected to the downstream end of a suction pipe 52, and the upstream end is connected to an air cleaner 51. There is.

A pressurizing intake passage 138 communicating with the compression chamber B and opening upward is integrally formed on the upper surface of the crankcase 40. In the pressurizing intake passage 138, the passage 1 is formed.
A partition wall 139 for partitioning the compression chamber B and the compression chamber B is integrally formed. A valve opening 140 that connects the pressurized intake passage 138 and the compression chamber B is formed in the partition wall 139, and the opening area of the valve opening 140 is set to a size that can sufficiently reduce the ventilation resistance.

The pressurized intake passage 138 has a predetermined volume larger than the cylinder stroke volume, stores the pressurized fresh air sent from the compression chamber B at each rotation of the crankshaft 64, and stores it in the crankshaft 64. It functions as a pressure accumulator for supplying pressurized intake air to the combustion chamber 65 every two revolutions.

A reed valve 142 for opening and closing the valve opening 140 is provided on the outer surface of the partition wall 139. The upper end opening of the pressurized intake passage 138 is closed by a cover plate 145, and the cover plate 145 and the pressurized intake passage 138 form a pressure accumulating chamber. The cover plate 145 has a pressure intake passage 13
8 is connected to the upstream end of the pressurized intake pipe 53, and the downstream end of the pressurized intake pipe 53 is connected to the intake port 105 of the cylinder head 42. The reed valve l4
In addition to 2, a reed valve that allows the flow of fresh air toward the crank chamber and blocks the reverse flow may be further arranged on the suction passage l35 side of the crank chamber suction port 40a. When the reed valve is arranged on the suction passage l35 side, the reed valve l4
You may abolish 2.

The pressurized intake passage 138 and the intake passage 135 are arranged on the outside of the engine 100 by the bypass pipe 1.
It is communicated through 50. The bypass pipe 150 can be opened and closed by a bypass valve 151. The bypass valve 151 is opened and closed in conjunction with the throttle 301, and for example, when the throttle opening is small, the bypass pipe 150
To reduce the pressure in the pressurized intake passage 138.

A carburetor 54 constituting the fuel supply device N is provided in the middle of the pressurized intake pipe 53. The carburetor 54 includes a cab body 401 and a float chamber 402, which serves as a fuel reservoir, fastened thereto by bolts.

In the cab body 401, a bottomed cylindrical variable piston valve 405 is axially slidably inserted. Throttle cable 4 for piston valve 405
One end of 07 is connected and throttle cable 40
The extension end of 7 is connected to the throttle 301. By operating the throttle 301, the piston valve 405 moves up and down to change the passage area of the venturi portion 403 from fully closed to fully open. The needle 412 moves back and forth as the piston valve 405 moves up and down, and the amount of fuel sucked into the venturi passage of the venturi portion 403 is adjusted.

A pressure pipe 426 is attached to the cab body 401.
Of the pressure pipe 426 is connected to the inside of the pressurized intake passage 138 through the cover plate 145. Thus, the supercharging pressure in the pressurized intake passage 138 is added to the liquid surface in the float chamber 402.

The middle of the pressure pipe 426 is branched into two paths by the first and second pressure passages 426a and 426b. The first and second pressurizing passages 426a, 4
26b has a narrowed portion 430 having large and small diameter throttle holes.
a and 430b are formed. In addition, the first pressurizing passage 4
26a, the first pressurizing passage 4 is provided upstream of the throttle portion 430a.
A solenoid valve 431 for opening and closing 26a is interposed, and the solenoid valve 431 is controlled to be closed / closed by the CPU 432.

The CPU 432 is configured to read the engine speed and the throttle opening, and control the solenoid valve 431 to be fully closed in the low speed rotation range and to be fully opened in the medium speed to high speed rotation range during idling. Therefore, the supercharging pressure is greatly attenuated by the small-diameter throttle hole 430b in the low intake air amount operation range such as idling, and is larger than the throttle hole 430b in the large-diameter throttle hole 430a in the high intake air amount operation range during high speed rotation. Is attenuated small.

Reference numeral 460 is a lubricating device, which is composed of a first lubricating system 461 and a second lubricating system 462 which is provided independently of the first lubricating system 461. The first lubrication system 461 connects the oil supply pipe 465 through the supply pump 464 to the first storage tank 463 filled with oil for four cycles, and the supply port 465 a of the supply pipe 465.
The camshaft 11 that constitutes the valve mechanism of the cylinder head 42
It is configured by connecting to part 0. In addition, the cam shaft 110
The oil that has lubricated the part returns to the inside of the chain chamber 110b in which the cam chain 48 is housed, where the cam chain 4
8, drive sprocket 113 and driven sprocket 2
01 are each lubricated, and thereafter, they are recovered by the first storage tank 463 through the recovery pipe 466.

The second lubrication system 462 includes a second storage tank 470 filled with two-cycle oil and a main supply pipe 4
71, the pressure feed pump 472 is connected, the first and second auxiliary supply pipes 473, 474 are connected to the pressure supply pump 472, the first auxiliary supply pipe 473 is connected to the piston sliding portion of the cylinder block 41, and the second The auxiliary supply pipe 474 is connected to the journal bearing portion of the crank chamber 63 (the left and right journal bearings 12
6,126).

Although not shown, the pressure feed pump 472 is an improved solenoid of an electromagnetic type autolube pump.
Secure the armature to the push rod of the plunger,
This is a method of attracting the armature with a solenoid. As a result, the discharge pressure from the pressure feed pump 472 is increased, and the supercharging pressure can be overcome to supply oil.

Oil discharge port 473 of the first auxiliary supply pipe 473
a is the cylinder block 41 in the direction orthogonal to the crankshaft 64.
Of the piston 61 located at the bottom dead center and located closer to the crank chamber than the second piston ring 350 of the piston 61 located at the bottom dead center. In addition, the outer surface of the piston 61 on the crank chamber side of the second piston ring 350 has a 2 in the crankshaft direction.
Recesses 475 and 476 for storing oil are formed by cutting out in parallel. The concave portion 475 is formed by the piston 61.
Of the discharge port 473a due to the movement of
By the oil supplied from 3a and accumulated, the recess 4
Reference numeral 76 performs lubrication at the time when the discharge port 473a is closed by the piston 61 by the oil accumulated and supplied from the discharge port 473a as described below.
This prevents a trouble in lubrication caused by closing the discharge port 473a with the piston 61.

An oil guide groove 481 extending in the circumferential direction is formed on the outer peripheral surface of the small end portion 62a of the connecting rod 62, and the piston 61 has this guide groove 481.
A communication hole 477 is formed so as to communicate with the lower recess 476. Further, a communication hole 47 communicating with the piston pin 66 and the bearing 67 is provided on the side of the small end portion 62a opposite to the communication hole 477.
8 are formed. As a result, the guide groove 481 supplied from the discharge port 473a and the oil recovery hole 480 described below.
Part of the oil inside is supplied to the bearing 67 from the communication hole 478, and the remaining part is supplied to the sliding surface between the small end portion 62a and the piston 61 from the communication hole 477, and further supplied to the recess 476. It has become.

Oil discharge port 474 of the second auxiliary supply pipe 474
The letter a passes through the crankcase 40 and reaches the journal bearing 126 on the right side in FIG. The oil supplied to the right journal bearing 126 is supplied to the inner peripheral walls 40c and 40d of the crankcase 40, the clearance between the circular recess 40e and the crankshaft 64, and the sliding surfaces.

A recovery hole 480 is formed, and a cover portion 136 attached to the lower portion of the crankcase 40 is further provided.
A recovery passage 483 is formed in the. Recovery passage 483
A recovery pipe 484 is connected to the recovery pipe 484.
Is connected to the second storage tank 470. As a result, the oil supplied from the first and second auxiliary supply pipes 473, 474 lubricates the sliding surfaces, then collects on the upper surface of the cover 136 in the suction passage 135, and is collected from there. In this embodiment, the engine 100 is placed horizontally, the compression chamber B having a high supercharging pressure is arranged upward, and air is sucked from below the crankcase 40. Therefore, the lubricating oil collects at the lowermost portion of the crankcase 40 due to the interaction between the gravity and the supercharging pressure, so that the oil can be reliably collected and reused. The inside of the crankcase 40 is separated by the oil seal 127b on the left side of FIG.
The side is lubricated with 2-cycle oil and the chain chamber 110b side is lubricated with 4-cycle oil.

Next, a schematic structure of the unit swing type engine unit 11 of the sixth embodiment will be described. First, FIGS. 18 and 19 show a sixth embodiment of a unit swing type engine unit equipped with an air-cooled 4-cycle supercharged engine, FIG. 18 is a side view of the unit swing type engine unit, and FIG. 19 is a unit swing type. It is a top view of a rotary engine unit.

A unit swing type engine unit 11 is mounted near the upper and lower bent portions of the left and right side frames 2c. In this engine unit 11, a bracket 30 provided on the front side of the transmission case 20 of the rear wheel transmission 13 and a bracket 31 of the side frame 2c are supported via a link 32, and provided on the rear side of the transmission case 20. The bracket 33 and the bracket 34 of the side frame 2c are supported via the rear suspension 15, and the engine unit 11 includes the link 32 and the bracket 3.
It is rotatable about a pivot shaft 32a between 0 and 0. Further, an elastic bush (not shown) is interposed between the bracket 31 and the link 32, and the elastic bush holds the link 32 so that the link 32 is not pivotally displaced about the support shaft 32b.

A stopper 35 for restricting the upward swing of the rear wheel transmission 13 is provided. This allows
When a vehicle body is held while preventing a fall by standing a stand 11a that is rotatably supported by the engine unit 11, the engine unit 11 is pushed up and the link 32 rotates upward, but a part of the link 32 stops. It abuts 35 and prevents interference with other parts of the engine body 12.

The engine body 12 is of a forced air cooling type 4-cycle single cylinder type, and has a structure in which a cylinder block 41 and a cylinder head 42 are connected to a crankcase 40. Cylinder bore 60 of cylinder block 41
While the piston 61 is slidably inserted and arranged in the inside,
The piston 61 is connected by a connecting rod 62 to a crankshaft 64 arranged in a crank chamber 63.

A forced cooling fan 43 for supplying cooling air is mounted on the engine body 12, and cooling fins 44 for increasing the heat radiation area are provided on the cylinder block 41. Although not shown, the cylinder head 42 also has cooling fins. A front air intake 45 is provided in the side cover 9 below the seat 10, and the front air intake 45 is composed of a slit 45a and a louver 45b, and the traveling wind is guided toward the engine body 12 from the front side. In addition, the lower cover 46 below the footboard 8
Is provided with a lower air intake 47, and the lower air intake 47 is composed of a slit 47a and a louver 47b, and the traveling wind is guided toward the engine body 12 from the lower side.

The engine body 12 is provided with a connecting rod supercharging device 50. The air filtered by the air cleaner 51 is sucked into the crank chamber 63 from the crank chamber suction port 40a on the front side of the crankcase 40 via the suction pipe 52. The air pressurized by the connecting rod supercharging mechanism in the engine body 12 constitutes the fuel supply device N from the crank chamber discharge port 40b on the rear side of the crankcase 40 via the pressurized intake pipe 53 constituting the pressurized intake passage. Is sent to the carburetor 54. The carburetor 54 transfers fuel from a suction port 42a on the rear side of the cylinder head 42 to a combustion chamber 65 via a pressurized intake pipe 55.
Is supplied to. Reference numeral 407 in the figure is a throttle cable for controlling the carburetor 54.

Since the engine unit 11 is displaced during traveling, the intake pipe 52 between the air cleaner 51 fixed to the vehicle body and the engine body 12 is provided with a bendable portion at a part or all of the portion. Further, the carburetor 54 is fixed to the cylinder block 41 or the cylinder head 42 via a vibration damping rubber mount (not shown).
Therefore, similarly, the bendable portion is arranged in a part or all of the pressure intake pipes 53, 55. Then, the engine unit 11 is displaced by the carburetor 5 as it is displaced during traveling.
4, the pressurized intake pipe 53, and the exhaust pipe 56, which will be described below, are displaced substantially integrally with the engine body 12.

Exhaust outlet 42b on the front side of the cylinder head 42
An exhaust pipe 56 is connected to the exhaust pipe 56. The exhaust pipe 56 extends downward from the front side of the engine unit 11 and further extends rearward from the lower right side, and a muffler 57 is connected to the rear end of the exhaust pipe 56.

Further, the engine body 12 has a lubricating device 4
The lubricating device 460 is provided with 60 to suck and pressurize the 2-cycle lubricating oil, and the pressurized lubricating oil is supplied to each bearing around the crankshaft 64, the piston sliding portion of the cylinder block 41, and the like. Four-cycle oil is circulated and supplied to the valve train in the cylinder head 42 by a lubricating device (not shown).

In this embodiment, the carburetor 54 has a pressurized intake passage for sending compressed fresh air from the crank chamber 63 to the combustion chamber 65.
Since it is arranged by the pressurized intake pipe 53 and the intake direction by this pressurized intake passage is directed from the lower side to the upper side, the lubricating oil supplied around the piston sliding portion and the crankshaft 64 is supplied to the combustion chamber 65. It becomes difficult to enter and stays in the crankcase 40, the piston sliding part, the connecting rod 62
Since it contributes to lubrication of the large and small end bearings and the lubrication necessary portion around the crankshaft 64, the supply of lubricating oil can be reduced accordingly, and the consumption of lubricating oil is reduced. In addition,
In this embodiment, in addition to the structures described in the claims, many unique effects can be obtained by many unique structures. These features are described below.

First, the carburetor 54, the pressurized intake pipes 53, 55, etc. are integrated with the carburetor 54, the pressurized intake pipes 53, 55, etc. at the rear side of the cylinder C, and the intake pipe for sending the compressed fresh air from the crank chamber 63 to the combustion chamber 65, 52 is integrated on the rear side of the cylinder C into a unit, and the bracket 30 provided on the front side of the transmission case 20 of the rear wheel transmission 13 and the bracket 31 of the side frame 2c are supported via a link 32. With the above-described front mount structure, the number of steps for assembling the engine unit 11 to the vehicle body can be reduced, and the engine unit 11 can be easily assembled.

Secondly, the carburetor 54 constituting the fuel supply device N is arranged so as to be inclined toward the downstream side, and the fuel supplied from the carburetor 54 adheres to the inside of the pressurized intake pipe 55 and becomes a mass. Supply to the combustion chamber 65 is prevented, fuel can be supplied smoothly, HC of exhaust gas is reduced, and adverse effects on engine performance can be avoided.

Thirdly, the air cleaner 51, the intake pipe 52, the crank chamber 63, the pressurized intake pipe 53, and the carburetor 54 are arranged on the same line along the cylinder axis L2 in the top view of the vehicle body, and the intake passage is formed. There is little bending, the flow path resistance can be reduced, the filling efficiency is improved, and the engine performance is improved.

20 and 21 show a seventh embodiment of a unit swing type engine unit equipped with a water-cooled partially air-cooled 4-cycle supercharged engine. FIG. 20 is a side view of the unit swing type engine unit. 21 is a plan view of the unit swing type engine unit. The engine unit 11 of this embodiment has the same configuration except that it is a water-cooled type instead of the air-cooled type of FIGS. 18 and 19, and therefore, the same reference numerals are given and the description thereof is omitted. Not only this embodiment, but also FIGS. 7 and 8, FIG. 11 and FIG. 12, and FIG.
And FIG. 14, FIG. 24 and FIG. 25, and FIG. 28 and country 29.
In each of the embodiments, not only the area around the cylinder head is cooled by the cooling water after being cooled by the radiator 70, but also a water jacket is provided in the pressurized intake passage 138 or the pressurized intake pipe 52, and cooling water is provided in this jacket. You may make it circulate. This surely improves the efficiency of filling the combustion chamber 65 with fresh air. The water jacket around the cylinder head and the water jacket of the pressurized intake pipe 52 are arranged in parallel or in series.

At the rear of the front air intake 45 of the side cover 9, a radiator 70 is arranged in parallel with the air cleaner 51 and at an upper position. In the radiator 70, the cooling water that has cooled the engine body 12 is supplied to the water pump 7
3 is returned by the drive of the return pipe 71, cooled by the radiator 70, and again sent to the engine body 12 via the feed pipe 72. Cooling water is supplied to the engine body 12 and the cylinder head 42 (not shown). Circulate to jacket to cool. A thermostat 74 is arranged above the cylinder head 42, and when the temperature of the cooling water reaches a predetermined temperature, it is returned to the return pipe 71 to improve the engine startability. Air-cooling fins are attached to the outer periphery of the cylinder block 41 for air-cooling. Note that this embodiment also has many features described as the first to third in the description of the sixth embodiment, in addition to the configuration described in the claims.

Next, still another embodiment of the unit swing type engine unit equipped with the connecting rod supercharged engine will be described with reference to FIGS. 22 to 33. In these embodiments, similarly, the crank chamber 63, the pressurized intake pipe 53, the inlet of the intake port 105 of the cylinder head 42, the intake port 105, and the intake valve 107 are arranged along the cylinder axis L2 in a top view of the vehicle body. Since the intake passages of the pressurization 5 in the crank chamber 63 are arranged so as not to bend, the efficiency of filling the combustion chamber 65 with fresh air is improved.
Further, from the air cleaner 51 before pressurization to the crankcase 4
The intake pipe 52 to the intake passage l35 arranged at the upper part of 0 is also arranged with less bending at a position closer to the cylinder center axis L2 in the top view of the vehicle body, so that the pipe resistance in the intake pipe 52 is reduced and the supercharging efficiency is reduced. As a result, the efficiency of filling the combustion chamber 65 with fresh air is improved. The same configurations as those described above are denoted by the same reference numerals and the description thereof is omitted, but the arrangement position of the air cleaner 51 is different. Further, the carburetor 54 is arranged above the engine 100, and the carburetor 5 is added to the air taken in from the air cleaner 51 to the upper side of the crank chamber 63.
4, fuel is supplied to the crank chamber 63 as an air-fuel mixture before pressurization. This air-fuel mixture is pressurized in the crank chamber 63 and supplied to the combustion chamber 65 from below the crank chamber 63 via the pressurized intake pipe 53 and the intake control valve 251, and the intake control valve 251 is operated by the throttle operation. It operates in conjunction with the carburetor 54. In these embodiments, the rotation direction of the crankshaft 64 is clockwise in FIG. That is, the rotation direction of the rear wheel 14 (counterclockwise in FIG. 18) is the reverse direction, and the rear wheel transmission device 13 shown in FIG. 34 or 35 is used.

Note that, in these embodiments as well, in addition to the configurations described in the claims, firstly, first, the air cleaner 40 is arranged in front of the engine body 12 on the rear wheel transmission device 13 side. The air cleaner 40 has a front air intake 4
Since cold fresh air from 5 can be inhaled, the filling efficiency is improved.

Secondly, as described above, the intake control valve 251
However, the carburetor 54 is arranged on the low pressure side of the supercharger by the throttle operation, and only the atmospheric pressure needs to be introduced into the float chamber 402, and 426, 431 and the like are unnecessary, and the cost can be reduced.

Third, the pressurized intake pipe 5 which is the pressurized intake passage.
3 will be located below the engine. As a result, the pressurized air intake passage is cooled by the cold air flowing from the front of the vehicle body to the lower portion of the vehicle body, so that the pressurized fresh air heated by the pressurization is cooled and the combustion chamber 65 is filled with fresh air to improve engine performance. Is improved.

Fourth, the exhaust pipe 5 is provided above the engine body 12.
6 and is arranged on the opposite side of the rear wheel transmission device l3. Therefore, a part of the cool air from the front air intake port 45 can cool the exhaust pipe 56 without being obstructed by the air cleaner 40. Also in the embodiment in which the radiator 70 is arranged, the radiator 70 is arranged in front of the engine body 12 and on the opposite side of the rear wheel transmission device 13 (see, for example, FIG. 25). Therefore, although the temperature of the air passes through the radiator 70 and slightly rises, the air is sufficiently exhausted from the exhaust pipe 56.
The exhaust pipe 56 can be cooled.

22 and 23 show a sixth embodiment of a unit swing type engine unit equipped with an air-cooled 4-cycle supercharged engine. FIG. 22 is a side view of the unit swing type engine unit, and FIG. 23 is a unit. It is a top view of a swing type engine unit. In the engine unit 11 of this embodiment, the pressure intake pipe 53 is
0 is located below the crankcase 40 and is connected to the lower side of the cylinder head 42.
3 can be shortened as much as possible, and the filling efficiency is improved. In addition, the traveling air hits the pressurized intake pipe 53 and the pressurized air sent to the combustion chamber 65 is cooled, and the charging efficiency is improved. This effect is further enhanced by disposing a plurality of cooling fins in the pressurized intake pipe 53. The exhaust pipe 56 is connected to the upper side of the cylinder head 42, extends rearward through the right side of the engine unit 11, and has a muffler 57 connected to the rear end thereof. The exhaust pipe 56 hits and the exhaust gas is cooled. An oil tank 500 and a fuel tank 501 are arranged below the seat 10.

24 and 25 show a ninth embodiment of a unit swing type engine unit equipped with a water-cooled 4-cycle supercharged engine. FIG. 24 is a side view of the unit swing type engine unit, and FIG. 25 is a unit. It is a top view of a swing type engine unit. The engine unit 11 of this embodiment is the same as the embodiment of FIG. 22 and FIG. 23 except that the radiator 70 is arranged on the right side of the air cleaner 51 and is arranged above and in front of the engine 100. The reference numerals are given and the description is omitted. Not only this embodiment, but also FIGS.
l and FIG. l2, FIG. l3 and FIG. 14, FIG. 28 and FIG.
32 and 33, in addition to cooling the periphery of the cylinder head with the cooling water after being cooled by the radiator 70, the pressurized intake passage 138 or the pressurized intake pipe 53 is provided with a water jacket, Cooling water may be circulated in this jacket. This surely improves the efficiency of filling the combustion chamber 65 with fresh air. The water jacket around the cylinder head and the water jacket of the pressurized intake pipe 53 are arranged in parallel or in series.

26 and 27 show a tenth embodiment of a unit swing type engine unit equipped with an air-cooled 4-cycle supercharged engine. FIG. 26 is a side view of the unit swing type engine unit, and FIG. 27 is a unit. It is a top view of a swing type engine unit. In the engine unit 11 of this embodiment, the pressurized intake pipe 53 is connected from the lower side of the crankcase 40 to the upper side through the right side of the cylinder head 42, and the pressurized intake pipe 53 has a predetermined length.
The traveling wind hits the pressurized intake pipe 53 and the pressurized air sent to the combustion chamber 65 is cooled, and the charging efficiency is improved. The exhaust pipe 56 is connected to the lower side of the cylinder head 42, extends rearward through the right side of the engine unit 11, and has a muffler 57 connected to the rear end thereof.

28 and 29 show an eleventh embodiment of a unit swing type engine unit equipped with a water-cooled 4-cycle supercharged engine. FIG. 28 is a side view of the unit swing type engine unit, and FIG. 29 is a unit. It is a top view of a swing type engine unit. The engine unit 11 of this embodiment is the same as the embodiment of FIG. 26 and FIG. 27 except that the radiator 70 is arranged on the right side of the air cleaner 51 and is arranged above and in front of the engine 100. The reference numerals are given and the description is omitted.

30 and 31 are a twelfth embodiment of a unit swing type engine unit equipped with a water-cooled 4-cycle supercharged engine. FIG. 30 is a side view of the unit swing type engine unit, and FIG. 31 is a unit. It is a top view of a swing type engine unit. The engine unit 11 of this embodiment has the same configuration as that of the embodiment of FIGS. 24 and 25, except that the supercharging tank 503 for suppressing the pressure fluctuation of the pressurized air supplied to the cylinder is provided in the pressurized intake pipe 53. The supercharging tank 503 is connected to the front side of the engine 100 and is cooled by running wind.

32 and 33 show a thirteenth embodiment of a unit swing type engine unit equipped with a water-cooled 4-cycle supercharged engine. FIG. 32 is a side view of the unit swing type engine unit, and FIG. 33 is a unit. It is a top view of a swing type engine unit. The engine unit 11 of this embodiment is configured as shown in the embodiments of FIGS. 28 and 29, but the intercooler 504 for cooling the air whose temperature has been raised by pressurization is provided in the pressurizing intake pipe 53, and the running wind Is applied to the intercooler 504 to cool and reduce the temperature. The intercooler 504 is the pressurized intake pipe 5
3, a cooling water jacket is provided on the outer periphery of part of the cooling water 3, and cooling water is circulated between the cooling water jacket and the radiator 70.

Next, the rear wheel drive system of the unit swing type engine unit 11 of the embodiment shown in FIGS. 22 to 33 will be described. In these embodiments, since the crankshaft 64 rotates clockwise, the rotation direction is opposite to that of the rear wheel 14. FIG. 34 is a sectional view of the rear wheel drive system in which the rear wheels rotate in the direction opposite to the engine rotation direction. The unit swing type engine unit 11 includes a rear wheel transmission 13, a power transmission mechanism 21 housed in a transmission case 20 of the rear wheel transmission 13, a V-belt automatic transmission 22 connected to a crankshaft 64, and a centrifugal unit. It comprises a clutch 23, an output shaft 26 and a gear train 24.

The gear train 24 includes a first gear 24j, a second gear 24k which is an internal gear, a third gear 24l and a fourth gear 2.
It is composed of 4 meters. The first gear 24j provided on the output shaft 26 is decelerated by the second gear 24k, the third gear 24l, and the fourth gear 24m and transmitted to the rear axle 25.
Since the second gear 24k is an internal gear, the rear wheels rotate in the direction opposite to the rotation direction of the engine. That is, the rear wheel 14 can be rotationally driven in the forward direction via the power transmission mechanism 21 by the engine that rotates in the direction opposite to the rotational direction of the wheels during forward movement.

FIG. 35 is a sectional view of another embodiment of the rear wheel drive system in which the rear wheels rotate in the direction opposite to the engine rotation direction.
The rear wheel transmission 13 of the unit swing type engine unit 11 includes a power transmission mechanism 21 housed in a transmission case 20 of the rear wheel transmission 13 as in the above-described embodiment, a V-belt automatic transmission 22 and a centrifugal clutch. 23 and the output shaft 2
6 and the gear train 24, the structure of the gear train 24 is different.

The gear train 24 is composed of a first gear 24n, a second gear 24o and the like. The first gear 24n provided on the output shaft 26 is decelerated by the second gear 24o and transmitted to the rear axle 25 so that the rear wheels rotate in the direction opposite to the engine rotation direction.

[0103]

As described above, according to the first aspect of the invention, since the crank chamber and the intake pipe are arranged along the cylinder axis in a top view of the vehicle body, the intake passage is less bent,
The flow resistance of compressed air is reduced and the filling efficiency is improved,
It is possible to avoid adverse effects on engine performance.

According to the second aspect of the present invention, the intake port and the intake valve are arranged at the end of the intake port on the combustion chamber side in the cylinder head, and the intake ports are arranged along the cylinder axis in a top view of the vehicle body. Therefore, the bending of the intake passage is small, the flow resistance of the compressed air is small, the filling efficiency is improved, and the adverse effect on the engine performance can be avoided.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a scooter type motorcycle.

FIG. 2 is a cross-sectional view of a rear wheel drive system in which the rear wheels rotate in the same direction as the engine rotation direction.

FIG. 3 is a sectional view of another embodiment of the rear wheel drive system in which the rear wheels rotate in the same direction as the engine rotation direction.

FIG. 4 is an external view of essential parts showing a state where the engine is mounted.

FIG. 5 is a side view of the air-cooled four-cycle unit swing type engine unit of the first embodiment.

FIG. 6 is a plan view of an air-cooled four-cycle unit swing type engine unit according to the first embodiment.

FIG. 7 is a side view of a water-cooled 4-cycle unit swing engine unit according to a second embodiment.

FIG. 8 is a plan view of a water-cooled 4-cycle unit swing engine unit according to a second embodiment.

FIG. 9 is a side view of an air-cooled four-cycle unit swing type engine unit according to a third embodiment.

FIG. 10 is a plan view of an air-cooled four-cycle unit swing type engine unit according to a third embodiment.

FIG. 11 is a side view of a water-cooled 4-cycle unit swing type engine unit according to a fourth embodiment.

FIG. 12 is a plan view of a water-cooled 4-cycle unit swing type engine unit according to a fourth embodiment.

FIG. 13 is a side view of another embodiment of the air-cooled 4-cycle unit swing engine unit of the fifth embodiment.

FIG. 14 is a plan view of an air-cooled 4-cycle unit swing engine unit according to a fifth embodiment.

FIG. 15 is a cross-sectional view of a supercharged engine.

16 is a sectional view taken along line XVI-XVI in FIG.

17 is a sectional view taken along line XVII-XVII in FIG.

FIG. 18 is a side view of an air-cooled four-cycle unit swing type engine unit according to a sixth embodiment.

FIG. 19 is a plan view of an air-cooled 4-cycle unit swing engine unit according to a sixth embodiment.

FIG. 20 is a side view of a water-cooled 4-cycle unit swing engine unit of a seventh embodiment.

FIG. 21 is a plan view of a water-cooled 4-cycle unit swing type engine unit according to a seventh embodiment.

FIG. 22 is a side view of an air-cooled 4-cycle unit swing engine unit of an eighth embodiment.

FIG. 23 is a plan view of an air-cooled four-cycle unit swing type engine unit according to an eighth embodiment.

FIG. 24 is a side view of a water-cooled 4-cycle unit swing type engine unit according to a ninth embodiment.

FIG. 25 is a plan view of a water-cooled 4-cycle unit swing type engine unit according to a ninth embodiment.

FIG. 26 is a side view of an air-cooled four-cycle unit swing type engine unit according to a tenth embodiment.

FIG. 27 is a plan view of an air-cooled four-cycle unit swing type engine unit according to a tenth embodiment.

FIG. 28 is a side view of a water-cooled four-cycle unit swing type engine unit according to an eleventh embodiment.

FIG. 29 is a plan view of a water-cooled 4-cycle unit swing engine unit of the eleventh embodiment.

FIG. 30 is a side view of a twelfth embodiment including a supercharging tank of an air-cooled four-cycle unit swing type engine unit.

FIG. 31 is a plan view of a twelfth embodiment including a supercharging tank of an air-cooled four-cycle unit swing type engine unit.

FIG. 32 is a side view of a thirteenth embodiment including an intercooler of a water-cooled 4-cycle unit swing type engine unit.

FIG. 33 is a plan view of a thirteenth embodiment including an intercooler for a water-cooled 4-cycle unit swing engine unit.

FIG. 34 is a cross-sectional view of a rear wheel drive system in which the rear wheels rotate in the direction opposite to the engine rotation direction.

FIG. 35 is a cross-sectional view of another embodiment of the rear wheel drive system in which the rear wheels rotate in the direction opposite to the engine rotation direction.

[Explanation of symbols]

 50 Supercharger 53 Pressurized Intake Pipe 62 Connecting Rod 63 Crank Chamber 65 Combustion Chamber 100 Engine C Cylinder N Fuel Supply Device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area F02M 35/16 F02M 35/16 L

Claims (2)

[Claims] 1. In a vehicle equipped with a supercharging engine for guiding fresh air pressurized by a supercharging device to a combustion chamber through a pressurized intake passage and an intake valve, a crank chamber in which a connecting rod is arranged, and a compression new compressor from this crank chamber. A supercharged engine-equipped vehicle, characterized in that a pressurized intake path for sending air to the combustion chamber is arranged along the cylinder axis in a top view of the vehicle body. 2. An intake valve is arranged in the cylinder head at the end of the intake port on the side of the combustion chamber of the intake port, and the intake port is arranged along the cylinder axis in a top view of the vehicle body. The vehicle equipped with the supercharged engine according to claim 1.