WO2002052140A1

WO2002052140A1 - Reciprocating internal combustion engine and its operating method

Info

Publication number: WO2002052140A1
Application number: PCT/JP2001/010113
Authority: WO
Inventors: Masatoshi Suzuki; Toshio Shimada; Ryo Kubota; Masashi Nakamura; Katsunori Takahashi
Original assignee: Honda Giken Kogyo Kabushiki Kaisha
Priority date: 2000-12-21
Filing date: 2001-11-20
Publication date: 2002-07-04
Also published as: JP2002250245A; KR20020081335A; AR032206A1; MY134561A; TW536581B; EP1344925A1; JP3642418B2; CN1404549A; EP1344925A4; BR0108515A; CN100408835C; BR0108515B1; TR200201967T1; KR100761188B1

Abstract

An operating method of a reciprocating internal combustion engine in which a net fuel consumption rate is improved by reducing frictional loss power at an indicated power of substantially the same magnitude as a conventional one thereby increasing net output. A reciprocating internal combustion engine having output characteristics generating a maximum indicated power PM when the rotational speed of the engine is a first specified r.p.m. N1 is provided with an output lowering means (26). The output lowering means (26) lowers the engine output when the rotational speed exceeds a second specified r.p.m. N2 so that a required indicated power PS is obtained from the internal combustion engine (output characteristics thereof are shown by a solid line) at the second specified r.p.m. N2 lower than the first specified r.p.m. N1. Since the high rotational speed region out of the engine rotational speed region R where the internal combustion engine is operated is set at an r.p.m. lower than an r.p.m. N3 generated at the required indicated power PS (maximum indicated power Pm) by a prior art (output characteristics thereof are shown by a dashed line), frictional loss power PL at an indicated power of substantially the same magnitude as a conventional one is reduced as compared with a conventional one thus increasing a net output and a net fuel consumption rate.

Description

Description Reciprocating internal combustion engine and its operating method

The present invention provides a reciprocating internal combustion engine having an output characteristic of generating a maximum indicated output when the engine speed is a first predetermined speed, wherein a required illustrated output is provided at an engine speed lower than the first predetermined speed. Background Art of Reciprocating Internal Combustion Engine and Operation Method

Conventionally, in a reciprocating internal combustion engine having a predetermined displacement, the maximum value of the indicated output (indicated output) represented by the performance curve when the internal combustion engine is fully loaded (or when the throttle valve is fully opened), that is, the maximum indicated output is It is determined depending on the specifications of the members constituting the internal combustion engine, such as the passage diameter of the intake / exhaust system, the diameter of the intake / exhaust valve, the lift amount, the compression ratio, and the like. The maximum indicated output determined in this manner increases as the displacement of the internal combustion engine increases. Also, when comparing a plurality of internal combustion engines having different displacements, the engine speed when the indicated output having the same magnitude is generated becomes lower as the displacement of the internal combustion engine is larger. The engine speed at which the maximum indicated output is generated is in the high rotation speed range of the engine rotation speed range in which the internal combustion engine is operated, and the maximum indicated output is the indicated output required by the internal combustion engine. Is the required output shown in FIG.

In a vehicular internal combustion engine, a start clutch that transmits torque of a crankshaft to a power transmission device including a transmission when a predetermined engine speed is reached is provided. When a centrifugal clutch having a clutch shaft composed of a centrifugal weight supported swingably on a support shaft is used as the starting clutch, the center of gravity of the clutch is shifted from the support shaft in the rotation direction of the crankshaft. The so-called leading type centrifugal clutch, which is located on the leading side, was used. In the leading type centrifugal clutch, the frictional force between the clutch outer member and the clutch shoe acts to swing the clutch shoe radially outward (hereinafter, a self-locking mechanism). It is called for. Therefore, there is an advantage that the torque transmission performance of the clutch, that is, the clutch capacity can be increased.

Further, the rotor of the alternator coupled to the crankshaft of the internal combustion engine is formed integrally with a flywheel for suppressing rotation fluctuation of the crankshaft.

By the way, a reciprocating internal combustion engine includes mechanical friction loss in each sliding portion such as a crankshaft, a crankpin, a piston, and a valve operating device, and auxiliary devices for driving various auxiliary devices such as an oil pump and a generator. Friction loss power including drive loss is generated. Therefore, the net output of the internal combustion engine is a value obtained by subtracting the friction loss power from the output shown. Since the frictional loss power increases with an increase in the engine speed, the indicated output increases as the engine speed increases, but the frictional loss power also increases at the same time. It is difficult to significantly improve the net fuel consumption rate, which is the unit net output and the fuel consumption rate per unit time, in the high rotation speed range including the rotation speed, and the driving frequency in the high rotation speed range is high. The fuel consumption rate of the internal combustion engine was worse.

Also, in the leading type centrifugal clutch, when the clutch is connected from the disconnected state, the self-locking action causes a sudden increase in the pressing force on the clutch shaft, that is, a sudden increase in the load acting on the crankshaft. The decrease in the number of rotations of the crankshaft, and the decrease in the pressing force of the clutch shoe against the clutch outer member due to the decrease in the number of rotations, that is, the increase in the number of rotations of the crankshaft due to the decrease in the load acting on the crankshaft As a result of the repetition, vibrations called “judder” tended to occur, and this vibration was transmitted to the occupants through the vehicle body. In an internal combustion engine whose operating range is a low rotational speed range, the engine speed at which the starting clutch is engaged is also low, so the weight of the clutch shoe must be increased to secure an appropriate clutch capacity. However, it is necessary to increase the size of the clutch shoe, but this will increase the vibration force applied to the vehicle body by the judder, and the transmitted vibration will cause discomfort to the occupant.

Furthermore, in order to adjust the degree of suppression of the fluctuation of the rotation of the crankshaft due to the flyhole, it is necessary to replace the flywheel with the AC generator integrated with the flywheel. However, there is a drawback that simple adjustment is not possible, and an internal combustion engine that operates at a low rotational speed range may require an additional flywheel that suppresses rotational fluctuations. In some cases, the space for installing a new flywheel must be secured, and the internal combustion engine may become larger.

The present invention has been made in view of such circumstances, and a high rotational speed range of an engine rotational speed range in which an internal combustion engine is operated has a lower rotational speed than an engine rotational speed at which a maximum illustrated output is generated. In addition, by obtaining the required indicated output in this high rotational speed range, the friction loss power at the indicated output of the same magnitude as before is reduced, and the net output is increased. It is an object of the present invention to provide a method of operating a reciprocating internal combustion engine that improves the performance.

Another object of the present invention is to provide a reciprocating internal combustion engine that performs the method of operating the reciprocating internal combustion engine. Further, in the reciprocating internal combustion engine, the reciprocating internal combustion engine is generated when a starting clutch including a centrifugal clutch is connected. It is an object of the present invention to reduce the judder and to obtain a flywheel structure capable of easily adjusting the rotational inertia mass without increasing the size of the internal combustion engine.

Disclosure of the invention

According to one aspect of the present invention, there is provided a method of operating a reciprocating internal combustion engine having an output characteristic of generating a maximum indicated output when the engine rotation speed is a first predetermined rotation speed, wherein the rotation speed sensor detects the engine rotation speed Providing a forward-reverse internal combustion engine having output reduction means for reducing the engine output, and when the engine rotation speed detected by the rotation speed sensor exceeds a second predetermined rotation speed less than the first predetermined rotation speed, Reducing the output of the internal combustion engine so that the required indicated output of the internal combustion engine is obtained at the second predetermined rotation speed by the output reduction means. .

According to the present invention, the output reduction means that operates when the second predetermined rotation speed is exceeded is requested by the internal combustion engine at the second predetermined rotation speed lower than the first predetermined rotation speed at which the maximum indicated output is obtained. The required illustrated output, which is the maximum illustrated output, is obtained. In the conventional reciprocating internal combustion engine, the maximum indicated output is the required indicated output. The internal combustion engine of the present invention has an output characteristic capable of generating a maximum indicated output larger than the required indicated output, and has a larger displacement than the conventional internal combustion engine. Therefore, the second predetermined rotational speed at which the required illustrated output is generated is lower than the engine speed at which the maximum illustrated output is generated in the conventional internal combustion engine, and the friction of the required illustrated output is reduced. Power loss is reduced compared to conventional internal combustion engines. Therefore, according to the present invention, even when the internal combustion engine is operated in the high rotation speed range of the rotation speed range, the friction loss power in the illustrated output is reduced as compared with the conventional internal combustion engine, and Net output increases. Further, according to the present invention, the internal combustion engine is operated in an engine rotation speed range having a high rotation speed range lower than that of a conventional internal combustion engine, so that the internal combustion engine can be operated in a rotation speed range higher than the engine rotation speed range. Unlike the conventional internal combustion engine, which is composed of components that require high rigidity and high strength in order to endure the internal combustion engine, the internal combustion engine can be composed of components having relatively low rigidity and strength. As described above, the required illustrated output is obtained at a lower engine speed as compared with the conventional internal combustion engine, and therefore, even in a high rotational speed range of the rotational speed range in which the internal combustion engine is operated according to the present invention. Among the outputs, the frictional loss power decreases, the net output increases, thereby improving the net fuel consumption rate, and improving the fuel consumption rate of the internal combustion engine that is frequently operated in the high rotational speed range. You. Further, in the present invention, since the internal combustion engine is operated in an engine rotation speed range having a high rotation speed range lower than that of a conventional internal combustion engine, the internal combustion engine may be constituted by components having relatively low rigidity and strength. As a result, the weight of the internal combustion engine can be reduced, and the fuel consumption rate is also improved in this respect. In the above reciprocating internal combustion engine operating method, when the first predetermined rotation speed is set as an upper limit, the engine rotation speed range is divided into three equal parts and divided into a low rotation speed range, a middle rotation speed range, and a high rotation speed range. The second predetermined rotation speed may be a rotation speed belonging to the medium rotation speed range or the low rotation speed range.

As a result, the engine speed becomes significantly lower than the engine speed at the time when the maximum indicated output of the conventional internal combustion engine is generated, and therefore the high engine speed including the second predetermined engine speed is obtained. Of the output power shown in the Compared to the internal combustion engine, it is greatly reduced and the net output is increased accordingly. In addition, since the internal combustion engine is operated in an engine rotation speed range having a high rotation speed range that is significantly lower than that of the conventional internal combustion engine, the internal combustion engine can be configured with components having lower rigidity and strength.

The internal combustion engine is connected to a manual transmission having a plurality of gears, and the second predetermined number of revolutions can be set corresponding to each gear of the manual transmission. As described above, the second predetermined rotation speed is set in accordance with each shift speed of the manual transmission, so that the second predetermined rotation speed in each shift speed is changed after securing the driving force for each shift speed. By doing so, the driving force at the time of shifting up can be arbitrarily changed. As a result, a change in driving force during upshifting can be made smooth, and smooth acceleration operation can be realized. Further, it becomes easy to secure the driving force for vehicles having gears with different reduction ratios and to adjust the driving force change at the time of shift-up.

The output reduction means can be performed by stopping the fuel supply to the internal combustion engine. By doing so, the fuel consumption is reduced as compared with, for example, controlling the ignition characteristics to reduce the engine output. The output reduction means can be performed by changing or controlling the ignition characteristics. Changing or controlling the ignition characteristics includes retarding or advancing the ignition timing from the optimal timing, or stopping or thinning out the ignition.

The internal combustion engine includes a rotation speed sensor that detects an engine rotation speed, an output reduction unit that reduces engine output, and a control unit, wherein the control unit determines whether the engine rotation speed detected by the rotation speed sensor is When the engine speed exceeds a second predetermined rotation speed that is lower than the first predetermined rotation speed, the engine output of the internal combustion engine can be reduced by the output reduction means.

The internal combustion engine is an internal combustion engine for a vehicle, the internal combustion engine including a crankshaft and a starting clutch coupled to the crankshaft and having a clutch outer member, and the starting clutch has exceeded a predetermined engine speed. At this time, a trailing-type centrifugal clutch having a clutch shoe composed of a swingable centrifugal weight abutting on the clutch rotor member can be provided. In a trailing type centrifugal clutch, the center of gravity of the clutch shoe is behind the support shaft in the direction of rotation of the crankshaft, so the clutch is brought into contact with the clutch outer member when the clutch is not connected. At times, the frictional force acts to swing the clutch shoe radially inward. Therefore, the change in the magnitude of the pressing force of the clutch against the clutch member is smaller than that of the leading type, and the pressing force, that is, the crankshaft caused by the increase in the load acting on the crankshaft, is increased. Of the rotational speed of the clutch shaft due to the decrease in the rotational speed of the clutch shaft due to the decrease in the rotational speed of the clutch shaft, that is, the increase in the rotational speed of the crankshaft due to the decrease in the load acting on the crankshaft. The fluctuation width can be reduced.

As a result, the amount of judder can be reduced, and the exciting force exerted on the vehicle by the generated judder becomes small, and the occupant's discomfort due to the transmitted vibration is reduced. Also, when the engine speed is low when the clutch is connected, the weight of the clutch shoe is increased, or even when the size of the clutch shoe is increased, the amount of judder is reduced while securing the appropriate clutch capacity. can do.

The reciprocating internal combustion engine includes a driven member connected to a crankshaft and rotationally driven by a motor, and a one-way clutch interposed between the crankshaft and the driven member and having an outer race. In this way, the arrester is detachably connected to a connection portion of the mouth of the alternator that rotates integrally with the crankshaft, and is extended radially outward from the connection portion. A flywheel with adjustable mass can be constructed.

As a result, an additional flywheel can be provided while avoiding an increase in the size of the internal combustion engine, and rotation fluctuation of the crankshaft can be further suppressed. In addition, the flywheel race that constitutes the flyhole can be attached to and detached from the mouth of the alternator, so that the rotational inertia mass of the flywheel can be easily adjusted by replacing only the flywheel. Thus, the degree of suppression of the rotation fluctuation can be easily adjusted.

The outer race has a maximum width in the axial direction outside a predetermined radius, and the coupling portion, which is one end in the axial direction of the rotor of the AC generator, fits inside the predetermined radius. It can be configured to have recesses that are mated. By doing so, the rotational inertia mass can be increased, and the connecting portion, which is one end of the alternator in the axial direction of the rotor, is fitted into the recess of the outer race. The dimension in the axial direction when the outer race and the rotor are connected can be reduced by the amount of the fitting.

As a result, it is possible to increase the rotational inertia mass while avoiding an increase in the size of the internal combustion engine, and to configure a flywheel that is effective in suppressing rotational fluctuations. In addition, since the connecting portion, which is one end in the axial direction of the mouth of the alternator at the inside of the predetermined radius and inside the predetermined radius, is fitted into the concave portion of the fan race, it is difficult to connect the rotor race with the rotor race. As the size in the axial direction is reduced, the size of the internal combustion engine can be prevented from increasing in this respect as well. In this specification, “axial direction” means the direction of the rotation axis of the crankshaft, and “radial direction” means the radial direction about the rotation axis of the crankshaft.

Brief explanation of drawings

FIG. 1 is a main part configuration diagram of a reciprocating internal combustion engine that is an embodiment of the present invention.

FIG. 2 is a plan sectional view taken on a plane including the rotation axis of the crankshaft of the internal combustion engine of FIG.

FIG. 3 is an enlarged plan sectional view of a main part of FIG.

FIG. 4 is a view taken along the arrow IV when the side plate of the AC generator and the one-way clutch in FIG. 3 is removed.

FIG. 5 is a view on arrow V when the drive plate is removed in FIG. FIG. 6 is a graph showing a comparison between the performance curve of the internal combustion engine of FIG. 1 and the performance curve of a conventional internal combustion engine.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

As shown in FIG. 1, a reciprocating internal combustion engine 1 to which the present invention is applied is a single cylinder overhead camshaft type four-cycle reciprocating internal combustion engine mounted on a motorcycle. Referring to FIGS. 1 and 2, which are diagrams, a spark-ignition and water-cooled internal combustion engine 1 The cylinder 3, the cylinder head 4, and the head force bar (not shown) are sequentially assembled on the upper end of the crankcase 2 to be integrated. A crankshaft 5 is rotatably supported on the crankcase 2 via a pair of main bearings 18 and 19, and a reciprocating motion of a piston 6 slidably fitted in the cylinder 3 is transmitted through a connecting rod 7. It is converted to the rotation of the crankshaft 5.

In FIG. 2, the left end of the crankshaft 5 extending leftward from the main bearing 18 has a driving sprocket 30, a star driven gear 62, and an alternator 31 running leftward from the main bearing 18 ^ 1. Are sequentially provided. A drive sprocket 30 is connected to the crankshaft 5 and a cam sprocket 33 is connected to a camshaft 32 rotatably supported by the cylinder head 4. A timing chain 34 is stretched between the sprocket 33 and the camshaft 32 to rotate at a rotation speed of the crankshaft 5 of 12. Further, a cooling water pump 36 is provided at the left end of the camshaft 5 and is drivingly connected to the camshaft 32 via a magnetic coupling 35 using a permanent magnet.

Referring also to FIGS. 3 and 4, the starter driven gear 62 as a driven member which is driven to rotate via the reduction gear 61 from the pinion gear 60a of the star motor 60 is connected to the inner peripheral surface of the boss portion 62a and the crank. The shaft 5 is rotatably supported by the crankshaft 5 via a large number of needles 63 arranged on the outer peripheral surface. The driven gear 62 is coupled to the crankshaft 5 via a well-known cam-type one-way clutch 64. That is, a later-described race 66 of the one-way clutch 64 is integrally rotated with the crankshaft 5 of the AC generator 31 by three ports B screwed into three screw holes H formed in the outer race 66. It is concluded on 31b.

The one-way clutch 64 includes a plurality of roller-like cams 67 having cam surfaces disposed between an annular boss portion 62a as an inner race 65 and an annular garage 66, and the cams 67 are mutually connected. It has a cam retainer 68 (Fig. 4) that holds it at a predetermined interval, a pair of side plates 69 and 70 that regulate the axial movement of each cam 67, and a spring 71 that is connected to each cam 67. ing.

As a result, at the time of starting, the rotation of the star motor 60 is transmitted from the pinion gear 60a. The power is transmitted to the driven gear 62 via the reduction gear 61, and further transmitted to the crankshaft 5 via the one-way clutch 64 and the rotor 31b, whereby the crankshaft 5 is driven to rotate. Then, when the internal combustion engine 1 starts rotating by itself and the rotation speed of the crankshaft 5 exceeds the rotation speed of the star driven gear 62, the transmission of the rotation from the crankshaft 5 to the star driving gear 62 is The clutch is disengaged by the one-way clutch 64. Further, the AC generator 31 includes a stay 31a fixed to the generator cover 37, and a bowl-shaped rotor 31b integrally connected to the crankshaft 5 surrounding the outside of the stay 31a. I can. The mouth 31b is keyed in the rotational direction to the crankshaft 5, and has a base 31c fastened by a nut 38 in the axial direction, and a bowl-shaped riveted to a flange 31cl of the base 31c. And a magnet holding portion 31d. The outer race 66 is detachably fastened by a port B to a flange portion 31cl as a connecting portion of the mouth 31b.

By the way, the outer race 66 is made larger in the radial direction than the conventional outer race by utilizing the space existing outside in the radial direction of the outer race of the conventional one-way clutch, and is more radially outer than the flange portion 31cl. Therefore, the arc race 66 extends to the vicinity of the inner peripheral surface 37a of the generator cover 37, and the outer peripheral surface 66a occupies a position close to the inner peripheral surface 37a. The end face of the outer race 66 on the rotor 31b side in the axial direction has a step of a predetermined width in the axial direction at a position substantially equal to the radius from the rotation axis of the flange portion 31c1 having a predetermined radius. A step 66b is formed. The outer race 66 has an outer portion 66c having a maximum width in the axial direction formed outside the stepped portion 66b over a radial range reaching the outer peripheral surface 66a, and is formed inside the stepped portion 66b. In addition, an inner portion 66d whose axial width is smaller than that of the outer portion 66c by the amount of the step is formed over a radial range up to the vicinity of the inner peripheral surface 66e, and the step portion 66b and the inner portion are formed. The portion 66d forms a concave portion 72 into which the flange portion 31cl is fitted.

As described above, the outer portion 66c of the outer race 66 is located radially outward from the flange portion 31cl, and utilizes the space in the axial direction existing between the one-way clutch 64 and the mouth 31b. The width in the axial direction can be increased, thereby It is possible to increase the mass of the side portion 66c. Therefore, the outer race 66 can be attached to and detached from the rotor 31b of the AC generator 31 that rotates integrally with the crankshaft 5, so that the rotary inertia mass can be adjusted by replacing only the outer race 66, and A flywheel for suppressing rotation fluctuation of the shaft 5 is configured.

On the other hand, the outer periphery of the right shaft end of the crankshaft 5 extending in the direction shown in FIG. 2 from the main bearing 19 is rotatably supported by the crankshaft 5 coaxially with the rotation axis L of the crankshaft 5. A cylindrical member 40 is provided, a drive gear 41 is formed on the main bearing 19 side of the cylindrical member 40, and a starting clutch 50 is provided at a right end of the cylindrical member 40.

Referring to FIGS. 2 and 5, the starting clutch 50 includes a drive plate 51 that rotates integrally with the crankshaft 5, and a bowl-shaped clutch member that is located outside the drive plate 51 and rotates integrally with the tubular member 40. And a centrifugal clutch having a member 52. A clutch shaft 54 composed of three centrifugal weights is supported on three support shafts 53 fixed to the drive plate 51 so as to be swingable. Each clutch shoe 54 has a lining 55 made of a friction material on its outer surface so that the center of gravity of the clutch shoe 54 is located on the delay side in the rotation direction A of the crankshaft 5 with respect to the position of the support shaft 53. When the starting clutch 50 is engaged, the frictional force acts to swing the clutch shoe 54 radially inward. Therefore, this centrifugal clutch is a so-called trailing centrifugal clutch.

The starting clutch 50 is configured to be connected when the engine speed N exceeds a predetermined speed. In other words, when the engine speed N exceeds the predetermined engine speed, the clutch 54 becomes radially outward around the support shaft 53 against the spring force of the clutch spring 56 due to the generated centrifugal force. Swings and comes into contact with the inner peripheral surface of the clutch gear 52 via the lining 55, and the connection of the starting clutch 50 is started, so that the drive plate 51 and the clutch outer member 52 eventually rotate integrally, The starting clutch 50 is completely connected.

The starting clutch 50 is a relatively large remote clutch capable of securing a clutch capacity capable of reliably transmitting torque even when the engine speed N of the internal combustion engine 1 is low. In order for the heart force to be generated in the clutch shoe 54, the clutch shoe 54 is made larger than that of the conventional internal combustion engine or provided with a clutch shoe 54 having a larger mass.

The driven gear 43, which engages with the drive gear 41, is rotatably supported by a main shaft 44 of a manual transmission M, which is a constantly meshing type gear transmission. Drive-coupled via a damper to a clutch outer member of a transmission clutch C provided at a right end protruding rightward (as viewed in FIG. 2) from the crankcase 2. The variable speed clutch C is a friction type multi-plate clutch having a number of clutch plates that are frictionally engaged or disengaged by a release mechanism operated by a driver. When a large number of clutch plates are friction-joined by spring force, the torque of the crankshaft 5 is transmitted to the clutch inner member integrally connected to the main shaft 44 via the clutch outer member, and the transmission clutch C is connected, On the other hand, when the frictional connection of many clutch plates is released, the transmission of torque from the clutch outer member to the clutch inner member is cut off, and the transmission clutch C is disconnected.

The manual transmission M disposed behind the crankshaft 5 in the crankcase 2 includes a main shaft 44 provided with a main gear group 45 and a counter shaft 46 provided with a counter gear group 47, and a shift operation (not shown). When the shift drum 48 is rotated by the mechanism, the shift fork engaged with the cam groove on the outer periphery of the shift drum 48 appropriately moves on the support shaft in the left-right direction (see FIG. 2), and the main gear group corresponding to the gear shifting operation Gears are shifted by appropriately meshing the gears of the 45 gears and the gears of the gear group 47.

On one side of the drive plate 51 in the axial direction, a centrifugal strainer 81 formed by being covered by a cover 80 is formed. The centrifugal strainer 81 passes through an oil passage 82 communicating with a main gallery (not shown). Foreign matter mixed into the lubricating oil supplied to the crankshaft 5 is separated by the centrifugal force in the centrifugal strainer 81, and clean lubricating oil passes through an oil passage 83 formed inside the crankshaft 5, such as the crankpin 5a. Supplied to lubrication points. Therefore, the torque of the crankshaft 5 is transmitted from the starting clutch 50 to the driving gear 41 integrated with the tubular member 40, and further through the primary reduction mechanism including the driving gear 41 and the driven gear 43 and the transmission clutch C. , Transmitted to the manual transmission M, Torque, is reached transferred to the rear wheel W _R through the counter Yujiku 46 from the secondary reduction mechanism (not shown), the rear wheel W _R is rotatably driven (see FIG. 1).

Referring again to FIGS. 1 and 2, in the internal combustion engine 1, a cylinder head 4 that forms a combustion chamber 8 with a piston 6 has an intake port 9 and an exhaust port respectively communicating with the combustion chamber 8. An intake valve 11 that opens and closes an opening of the intake port 9 on the combustion chamber 8 side and an exhaust valve 12 that opens and closes an opening of the exhaust port 10 on the combustion chamber 8 side are provided. The intake valve 11 and the exhaust valve 12 are driven to open at a predetermined opening / closing timing and lift amount in synchronization with the crankshaft 5 by a valve train including a camshaft 32 and a rocker arm (not shown). You. Further, facing the combustion chamber 8, an ignition plug 13 for igniting the air-fuel mixture in the combustion chamber 8 is attached to the cylinder head 4.

An intake pipe 14 is connected to an opening on the side of the cylinder head 4 on the upstream side of the intake port 9, and the fuel that supplies fuel toward the intake port 9 to form an air-fuel mixture is formed in the intake pipe 14. While an injection valve 16 is provided, an exhaust pipe 15 is connected to an opening on the side of the cylinder head 4 downstream of the exhaust port 10.

An electronic control unit (ECU) 20, which is a control means for controlling the fuel injection amount and the ignition timing, includes a speed sensor 21 for detecting an engine speed N, an opening sensor 22 for detecting a throttle valve opening, and a throttle. A pressure sensor 23 for detecting the intake pressure downstream of the valve, a temperature sensor for detecting the cooling water temperature 2 A detection from the various sensors 21 to 25 which are detection means for detecting an operation state of the internal combustion engine 1 such as a gear position switch 25 and the like. Based on these detection signals, fuel is injected from the fuel injection valve 16 at an injection amount according to the engine operating state, and the timing of the generation of high voltage in the ignition coil 17 is controlled to cause ignition. The plug 13 ignites at an ignition timing according to the engine operating state.

Here, referring to FIG. 6, which shows a performance curve at the time of full load of the internal combustion engine (when the throttle valve is fully opened), the internal combustion engine 1 having a set displacement, for example, a displacement of 200 cc is shown in FIG. As shown by the two-dot chain line, when the engine speed N is 600 rpm, which is the first predetermined speed N1, the maximum illustrated value which is the maximum value of the indiced output of the internal combustion engine 1 It has output characteristics that generate output PM. This maximum indicated output PM is based on the specifications of the members constituting the internal combustion engine 1 (intake and exhaust system passage diameter, intake valve 11 and exhaust valve 12 Diameter, lift, compression ratio, etc.). In FIG. 6, a solid curve PL indicates a friction loss power curve of the internal combustion engine 1.

According to the present invention, in the internal combustion engine 1 having the output characteristic of generating the maximum indicated output PM at the first predetermined rotation speed N1, the second predetermined rotation speed N2 less than the first predetermined rotation speed N1, for example, 3500 At rpm, the required indicated output PS which is the maximum value of the indicated output required for the internal combustion engine 1 is obtained. For this purpose, when the engine speed N detected by the speed sensor 21 (FIG. 1) exceeds the second predetermined speed N2, a signal is input from the speed sensor 21 to the electronic control unit 20, and A series of arithmetic processing is performed according to the signal, and a signal for stopping the driving of the fuel injection valve 16 is output from the output reduction means 26 to the fuel injection valve 16, and the supply of fuel from the fuel injection valve 16 is cut off As a result, the output of the internal combustion engine 1 is reduced.

The second predetermined rotation speed N2 is determined in consideration of the displacement and the maximum indicated output PM, on condition that the required indicated output PS of the internal combustion engine 1 is obtained. Then, it is assumed that the internal combustion engine 1 is operated in a rotation speed range from a stop (the engine rotation speed N is 0 (zero)) to a first predetermined rotation speed N1 as an upper limit value. Assuming that the region is divided into three equal parts and divided into a low rotational speed region, a medium rotational speed region, and a high rotational speed region, in this embodiment, the second predetermined rotational speed N2 belongs to the medium rotational speed region of the internal combustion engine 1. It is the engine speed. This medium rotation speed range belongs to the high rotation speed range of the engine rotation speed range R (FIG. 2) in which the internal combustion engine 1 is operated.

Next, the operation and effect of the embodiment configured as described above will be described. Referring to FIG. 6, the output characteristic of a conventional reciprocating internal combustion engine having a displacement of approximately 1/2 of the displacement of the internal combustion engine 1 and generating the maximum indicated output Pm equal to the required indicated output PS, The friction loss power curve including the friction loss power PLm of the output Pm is shown by the broken line. Figure 6 shows the following. That is, the engine speed at which the required indicated output PS of the internal combustion engine 1 is obtained, that is, the second predetermined speed N2 is equal to or less than 1/2 of the speed N3 when the maximum indicated output Pm is generated in the conventional internal combustion engine. Further, the friction loss power PLM of the required illustrated output PS of the internal combustion engine 1 is represented by 1 of the friction loss power PLm of the maximum indicated output Pm of the conventional internal combustion engine indicated by a broken line. 2 or less. When the internal combustion engine 1 is compared with the conventional internal combustion engine, the internal combustion engine 1 has a smaller friction loss power PL among the illustrated outputs of the same magnitude than the conventional internal combustion engine. In obtaining the data of the frictional loss power PL shown in FIG. 6, in the internal combustion engine 1 and the conventional internal combustion engine, the sliding portion where mechanical frictional loss occurs is the same, and an auxiliary machine drive loss is generated. Auxiliary equipment was identified.

As described above, in the internal combustion engine 1 having the output characteristic of generating the maximum indicated output PM when the engine speed N is the first predetermined speed N1, the internal combustion engine 1 is lower than the first predetermined speed N1. Rotational speed range (Medium rotational speed range when the engine rotational speed range when the first predetermined rotational speed N1 is set as the upper limit is divided into three, and divided into low rotational speed region, medium rotational speed region, and high rotational speed region The output reduction means 26, which operates when the second predetermined rotation speed N2 belonging to the above-mentioned range is exceeded, is provided at the second predetermined rotation speed N2 which is significantly lower than the first predetermined rotation speed N1 at which the maximum indicated output PM is obtained. The required indicated output PS, which is the maximum indicated output required for the internal combustion engine 1, is obtained. Since the maximum indicated output is the required indicated output PS in the conventional internal combustion engine, the internal combustion engine 1 has an output characteristic capable of generating the maximum indicated output PM larger than the required indicated output PS. The internal combustion engine has a larger displacement than conventional internal combustion engines. The second predetermined rotational speed N2 at which the required illustrated output PS is generated is significantly lower than the engine speed N3 when the maximum illustrated output Pm is generated in the conventional internal combustion engine. The friction loss power PLM of the output PS is significantly reduced as compared with the conventional internal combustion engine. Therefore, even when the internal combustion engine 1 is operated in the high rotation speed range of the engine rotation speed range R, the friction loss power PL in the illustrated output is significantly reduced as compared with the conventional internal combustion engine. Accordingly, the net output increases accordingly, so that the net fuel consumption rate is greatly improved, and the fuel consumption rate of the internal combustion engine 1 is improved even when the operation frequency in the high rotation speed region is high. Further, since the internal combustion engine 1 is operated in the engine speed range R having a high speed range that is significantly lower than that of the conventional internal combustion engine, the internal combustion engine 1 operates at a speed higher than the engine speed range R. Unlike the conventional internal combustion engine, which consists of components that require high rigidity and high strength in order to withstand operation, Oka IJ Can be configured. As a result, the internal combustion engine 1 can be reduced in weight, Also in this respect, the fuel consumption rate is improved.

When the engine speed exceeds the second predetermined speed N2, the output reduction means 26 cuts the fuel supplied to the internal combustion engine 1, so that the ignition timing is controlled to reduce the engine output. Therefore, fuel consumption is reduced and the fuel consumption rate is further improved. Further, although the internal combustion engine 1 is operated in the engine rotation speed range R having a high rotation speed range that is significantly lower than that of the conventional internal combustion engine, the starting clutch 50 provided on the crankshaft 5 and Since the AC generator 31 functions as a rotating inertial mass added to the crankshaft 5, rotation fluctuation of the crankshaft 5 having a low rotation speed is suppressed, and smooth operation is possible. Further, since the internal combustion engine 1 is operated in a lower rotational speed range than the conventional internal combustion engine, the starting clutch 50 is provided in the conventional internal combustion engine so that torque can be reliably transmitted even at a low rotational speed. Since the size of the centrifugal weight is made larger than that of the conventional internal combustion engine or a centrifugal weight having a larger mass than that of the conventional internal combustion engine, the rotational inertial mass can be increased, and the rotational fluctuation is further suppressed. You. In addition, since the starting clutch 50 is constituted by a trailing centrifugal clutch, the center of gravity of the clutch shoe 54 is on the side of the rotation direction A of the crankshaft 5 behind the support shaft 53, and the engine speed N is low. Exceeding the predetermined engine speed, when the starting clutch 50 is disengaged from the disengaged state and the lining 55 of the clutch shoe 54 comes into contact with the clutch outer member 52, when the clutch is connected, the friction force moves the clutch shoe 54 radially inward. Acts to rock. Therefore, the change in the magnitude of the pressing force of the clutch shoe 54 against the clutch outer member 52 is smaller than that of the leading type, and is caused by an increase in the pressing force, that is, an increase in the load acting on the crankshaft 5. The rotation speed of the crankshaft 5 due to the decrease in the rotation speed of the crankshaft 5 and the decrease in the pressing force of the clutch shaft 54 against the clutch member 52 due to the reduction in the rotation speed, that is, the reduction in the load acting on the crankshaft 5 The fluctuation range of the rotation speed due to the repetition of the rise of the vibration can be reduced, the judder can be reduced, and the generated excitation force on the vehicle by the judder becomes smaller, and the transmitted vibration The occupant's discomfort due to is reduced.

The second predetermined rotation speed N2 belongs to the medium rotation speed range, and the conventional rotation speed N2 Since the engine speed is less than half of the engine speed N3 when the maximum indicated output Pm is generated in the internal combustion engine, the internal combustion engine 1 is in the engine speed range R that belongs to a lower speed range than the conventional engine. Even when the vehicle is driven, it is possible to increase the weight of the clutch shoe 54 or increase the size of the clutch shoe 54 to secure an appropriate clutch capacity, and to reduce judder.

The outer race 66 of the one-way clutch 64 that couples the star driven gear 62 to the crankshaft 5 uses a space that exists radially outside the outer race of the conventional one-way clutch, and uses a space existing outside of the alternator 31. The flywheel 31 is formed by being connected to the flange portion 31 cl of the overnight portion 31 b and extending radially outward from the flange portion 31 cl. The flywheel can be additionally provided while avoiding an increase in the size of the crankshaft, and the rotation fluctuation of the crankshaft 5 can be further suppressed. Moreover, since the flywheel 66 constituting the flyhole can be attached to and detached from the rotor 31b of the AC generator 31, it is easy to adjust the rotational inertia mass of the flywheel by replacing only the flywheel race 66. Therefore, the degree of suppression of the rotation fluctuation can be easily adjusted.

The outer race 66, which has been enlarged in the radial direction, uses the space existing in the axial direction outside the radial direction of the flange portion 31c1 of the mouth 31b, and is larger than the predetermined radius at which the stepped portion 66b is formed. Also, since the outer portion 66c formed on the outside has the maximum width in the axial direction, the rotating inertial mass can be further increased while avoiding an increase in the size of the internal combustion engine 1.

Therefore, the second predetermined rotation speed N2 belongs to the medium rotation speed range, and is not more than 1/2 of the engine rotation speed N3 when the maximum indicated output Pm is generated in the conventional internal combustion engine. As a result, even when the internal combustion engine is operated in the engine speed range R, which belongs to a lower speed range than before, the enlargement of the internal combustion engine 1 is avoided by using the outer race 66 of the one-way clutch 64. In addition, it is possible to increase the number of flywheels, and furthermore, it is possible to increase the rotational inertia mass, and to configure a flywheel that is effective in suppressing rotation fluctuation of the crankshaft 5.

Moreover, the inner side of the predetermined radius and the axial direction of the rotor 31b of the alternator 31 The flange portion 31cl, which is one end portion, is fitted into the concave portion 72 of the outer race 66, and the axial direction when the outer race 66 is connected to the rotor 31b by the amount of the fitting (step difference). In this respect, the size of the internal combustion engine 1 can be prevented from increasing in size. Hereinafter, an embodiment in which a part of the configuration of the above-described embodiment is changed will be described only with respect to the changed configuration.

In the above-described embodiment, the second predetermined rotation speed N2 is a rotation speed belonging to the middle rotation speed range.However, the second predetermined rotation speed N2 may be less than the first predetermined rotation speed N1. As described above, it is determined on the basis of the displacement of the internal combustion engine 1 and the maximum indicated output PM. Also according to this, the degree of improvement in the fuel consumption rate and the reduction in the weight of the internal combustion engine 1 as compared with the above embodiment are also determined. However, the same effects as those of the above-described embodiment, such as an improvement in the net fuel consumption rate and a reduction in the weight of the internal combustion engine 1, are achieved.

Further, as shown in FIG. 1, a gear position switch 25 for detecting a shift position of the manual transmission M is provided, and the second predetermined rotation speed N2 has a shift speed from the first speed to the fourth speed. The setting may be made so as to correspond to each shift speed of the transmission M. At this time, the second predetermined rotation speed N2 is the highest in the first speed, the second predetermined rotation speed N2 in the first speed is the highest, and the second predetermined rotation speed The second predetermined rotational speed at each shift speed is set so as to gradually decrease as the gear ratio decreases.

In this way, the second predetermined number of revolutions N2 is set corresponding to each gear position of the manual transmission M, so that the driving force for each gear position is ensured, and that By changing the second predetermined rotation speed N2, the driving force at the time of shift-up can be arbitrarily changed, thereby smoothing the driving force change at the time of up-shifting and realizing smooth acceleration operation. In addition, it is easy to secure the driving force for vehicles having gears with different reduction ratios and to adjust the change in driving force during upshifting.

In the above-described embodiment, the output reduction means 26 controls the fuel injection valve 16 to perform the fuel cut. However, the output reduction means 26 may reduce the fuel injection amount. The engine output of the internal combustion engine 1 may be reduced by greatly retarding or advancing the ignition, or by stopping or thinning out the ignition. . When the fuel injection amount is reduced, the ignition timing is retarded or advanced, or the ignition is thinned out by the output reduction means 26, the output reduction when exceeding the second predetermined rotation speed N2 is as shown in FIG. As shown by the dashed line in Fig. 6, the speed is slower than when the fuel cut is executed, and in these cases, the maximum rotation speed can be regulated by the fuel cut or the stop of the ignition.

When the displacement of the internal combustion engine 1 is large and the required indicated output PS is small, the second predetermined rotation speed N2 is a low rotation speed in the engine rotation speed range when the first predetermined rotation speed N1 is set to the upper limit. The engine speed N belonging to the range can also be used. Further, the internal combustion engine 1 may be a multi-cylinder, and the vehicle may be a vehicle other than a motorcycle.

In the above embodiment, the recess 72 was formed in the outer race 66. However, the recess 72 may not be provided, and the predetermined radius is the radius of the flange 31cl of the base 31c of the rotor 31b. The radius of the part 31 cl may be larger.

Claims

The scope of the claims

1. A method of operating a reciprocating internal combustion engine having an output characteristic of generating a maximum indicated output when the engine rotational speed is a first predetermined rotational speed, including the following steps.

Providing a reciprocating internal combustion engine having a rotation speed sensor for detecting the engine rotation speed and an output reduction means for reducing the engine output; and

When the engine rotation speed detected by the rotation speed sensor exceeds a second predetermined rotation speed that is less than the first predetermined rotation speed, the output reduction means causes the required illustrated output of the internal combustion engine to be output at a second predetermined rotation speed. Reducing the output of the internal combustion engine so that

2. A method for operating a reciprocating internal combustion engine according to claim 1,

When the engine rotational speed range when the first predetermined rotational speed is set to the upper limit value is divided into three equal parts and divided into a low rotational speed region, a medium rotational speed region, and a high rotational speed region, the second predetermined rotational speed is: The number of rotations belongs to the medium rotation speed range or the low rotation speed range.

3. A method for operating a reciprocating internal combustion engine according to claim 1,

The internal combustion engine is connected to a manual transmission having a plurality of gears,

The second predetermined number of revolutions is set corresponding to each shift speed of the manual transmission.

4. A method for operating a reciprocating internal combustion engine according to claim 1,

The output reduction means stops fuel supply to the internal combustion engine.

5. The method for operating a reciprocating internal combustion engine according to claim 1,

The output reduction means changes ignition characteristics of the internal combustion engine.

6. A reciprocating internal combustion engine having an output characteristic of generating a maximum indicated output when the engine speed is a first predetermined speed,

A rotation speed sensor for detecting an engine rotation speed,

Output reduction means for reducing engine output;

Control means; and

The control means may control the engine speed detected by the engine speed sensor to be equal to the engine speed. When the engine speed exceeds a second predetermined rotation speed that is less than one predetermined rotation speed, the output reduction means is operated so as to reduce the output of the internal combustion engine.

7. The reciprocating internal combustion engine according to claim 6, wherein

The internal combustion engine is a vehicle internal combustion engine,

The internal combustion engine is

A crankshaft,

A starting clutch coupled to the crankshaft and having a clutch outer member;

The starting clutch is a trailing centrifugal clutch having a clutch shoe composed of a swingable centrifugal weight that comes into contact with the clutch rotator member when a predetermined engine rotation speed is exceeded.

8. The reciprocating internal combustion engine according to claim 7, wherein

A driven member connected to the crankshaft and driven to rotate by a star motor;

A one-way clutch interposed between the crankshaft and the driven member and having an outer race;

The outer race is detachably connected to a connection portion of a rotor of the AC generator that rotates integrally with the crankshaft, and extends radially outward from the connection portion, thereby adjusting a rotational inertial mass. A possible flyhole is configured.

9. The reciprocating internal combustion engine according to claim 8, wherein

The outer race has a maximum width in the axial direction outside a predetermined radius, and the coupling portion, which is one end of the rotor of the AC generator in the axial direction, is fitted inside the predetermined radius. Having a concave portion.