KR100761188B1 - Reciprocating internal combustion engine and its operation method - Google Patents

Abstract

Provided is a method of operating a reciprocating internal combustion engine which reduces the frictional loss power at the city output of the same size as the conventional one, increases the netting output by improving the net fuel consumption rate. The output reduction means 26 is provided in the reciprocating internal combustion engine having the output characteristic of generating the maximum city output PM when the engine rotational speed is the first predetermined rotational speed N1. The output reducing means 26 obtains the required drawing output PS of this internal combustion engine (the output characteristic of which is shown by the solid line) at the second predetermined rotation speed N2 less than the first predetermined rotation speed N1, The engine output is lowered when the rotation speed exceeds the second predetermined rotation speed N2. Thereby, the high speed range of the engine speed range R in which the internal combustion engine is operated is in the prior art (the output characteristic is shown by the broken line), and the required city output PS (maximum city output Pm) is The engine speed is set lower than the engine speed N3 to be generated, and the frictional loss power PL in the city output of the same magnitude as the conventional one is reduced, the net power is increased, and the net fuel consumption rate is improved. do.

Description

Reciprocating internal combustion engine and its operation method {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 municipal output when the engine rotational speed is a first predetermined rotational speed, the reciprocating motion of obtaining a required city output at an engine rotational speed less than the first predetermined rotational speed. It relates to an internal combustion engine and its driving method.

Conventionally, in a reciprocating internal combustion engine having a predetermined displacement, the maximum value of the dedicated output, that is, the maximum urban output, which is represented by a performance curve when the internal combustion engine is fully loaded (or when the throttle valve is fully opened) is absorbed. It is determined depending on the specifications of the members constituting the internal combustion engine, such as the passage diameter of the exhaust system, the diameter and lift amount of the intake / exhaust valve, and the compression ratio. And the maximum city output determined in this way becomes large, so that the displacement of an internal combustion engine is large. In addition, compared with a plurality of internal combustion engines having different displacements, the engine speed when generating an urban output of the same size decreases as the displacement of the internal combustion engine increases. The engine speed at which the maximum city power is generated is in the high speed range among the engine speed ranges at which the internal combustion engine is operated, and this maximum city power is the required city output which is the maximum of the city power required for the internal combustion engine. It is becoming.                 

Moreover, in a vehicle internal combustion engine, when the predetermined engine speed reaches, the oscillation clutch which transmits the torque of a crankshaft is provided in the power transmission device comprised by a transmission etc. As the oscillating clutch, when a centrifugal clutch having a clutch shoe made of a centrifugal weight supported to be swingably supported on a support shaft is used, the center of the clutch shoe is located in front of the support shaft in the rotational direction of the crankshaft. A so-called leading centrifugal clutch was used. In the leading-type centrifugal clutch, since the frictional force between the clutch outer member and the clutch shoe acts to swing the clutch shoe radially outward (hereinafter referred to as a self locking action), There is an advantage in that the torque transmission performance, that is, the clutch capacity, can be increased.

In addition, the rotor of the alternator coupled to the clutch shaft of the internal combustion engine is integrally formed with a flywheel for suppressing the rotational fluctuation of the crankshaft.

By the way, in a reciprocating internal combustion engine, friction consists of a mechanical friction loss in each sliding part of a crankshaft, a crank pin, a piston, a valve device, etc., and the power loss of the auxiliary equipment for driving various auxiliary equipments, such as an oil pump and a generator. Loss of power is generated. Therefore, the net power of this internal combustion engine is a value obtained by subtracting the frictional loss power from the city output. Since the frictional loss power increases with the increase of the engine speed, the urban power increases as the engine speed increases, but at the same time, the frictional loss power also increases, so that the high rotational speed including the engine speed at which the maximum city power is generated is included. In the speed range, it is difficult to drastically improve the net fuel consumption rate, which is the unit net power output and the fuel consumption rate per unit time, and the fuel consumption rate is deteriorated in the internal combustion tube having a high operating frequency in the high rotation speed range.

Moreover, in the leading-type centrifugal clutch, when the clutch is connected in a non-connected state, it is caused by a sudden increase in the pressing force of the clutch shoe against the clutch outer by the self-fastening action, that is, a sudden increase in the load acting on the crankshaft. As a result of repeating the decrease in the rotational speed of the crankshaft and the increase in the rotational speed of the crankshaft due to the decrease in the pressing force on the clutch outer member of the clutch shoe due to the decrease in the rotational speed, that is, the decrease in the load acting on the crankshaft, A vibration called a judder is likely to occur, and this vibration has been transmitted to the rider through the vehicle body. In addition, since the engine speed at which the oscillation clutch is connected is also reduced in an internal combustion engine having a low rotational speed range as its operating range, in order to ensure proper clutch capacity, the weight of the clutch shoe may be increased or the clutch shoe may be Although it is necessary to enlarge, this increases the vibration force on the vehicle body due to the abnormal vibration, and the transmitted vibration imparts discomfort to the rider.

In addition, in order to adjust the degree of suppression of the rotational fluctuation of the crankshaft by the flywheel, it is necessary to replace the flywheel and the integrated alternator together with the flywheel, which makes it difficult to make simple adjustments. In an internal combustion engine having an operating range, an additional flywheel for suppressing rotational fluctuations may be required. In such a case, the internal combustion engine has become larger since it is necessary to secure a space for installing a new flywheel.

The present invention has been devised in view of such circumstances, and the high speed range of the engine speed range at which the internal combustion engine is operated is set to a lower speed than the engine speed at which the maximum urban output is generated, and the high speed range By providing the required city output in the above, the friction loss power in the city output of the same size as in the prior art is reduced by increasing the net power output, thereby improving the net fuel consumption rate. For the purpose of

Moreover, an object of this invention is to provide the reciprocating internal combustion engine which performs the operation method of the said reciprocating internal combustion engine, Moreover, in the said reciprocating internal combustion engine, it arises at the time of connection of the oscillation clutch which consists of a centrifugal clutch. It is an object of the present invention to reduce the abnormal vibration and to obtain a flywheel structure that can easily adjust the rotational inertia mass without increasing the internal combustion engine.

According to an embodiment of the present invention, a rotation speed sensor and an engine for detecting an engine rotation speed in a method of operating a reciprocating internal combustion engine having an output characteristic of generating a maximum city output when the engine rotation speed is a first predetermined rotation speed. Providing a reciprocating internal combustion engine having an output reduction means for lowering the output, and output reduction means when the engine rotational speed detected by the rotational speed sensor exceeds a second predetermined rotational speed less than the first predetermined rotational speed; Thereby, there is provided a method of operating a reciprocating internal combustion engine, which comprises the step of lowering the output of the internal combustion engine so that the required city output of the internal combustion engine is obtained at the second predetermined rotational speed.

According to the present invention, the maximum drawing required for the internal combustion engine at the second predetermined rotation speed lower than the first predetermined rotation speed at which the maximum city output is obtained by the output reduction means operating when the second predetermined rotation speed is exceeded. The required city output, which is an output, is obtained. In the conventional reciprocating internal combustion engine, since the maximum city output is the required city output, the internal combustion engine of the present invention has an output characteristic capable of generating a maximum city output larger than the required city output. The internal combustion engine has a larger displacement than the conventional internal combustion engine. For this reason, the second predetermined rotational speed at which the necessary city output occurs is lower than the engine rotational speed when the maximum city output occurs in the conventional internal combustion engine. It decreases compared with the conventional internal combustion engine. Therefore, according to the present invention, even when the internal combustion engine is operated at a high rotational speed range of the rotational speed range, the frictional loss power in the city output is lower than that of the conventional internal combustion engine, and the net output is increased. In addition, according to the present invention, since the internal combustion engine is operated in the engine rotation speed range having a lower high rotation speed range than the conventional internal combustion engine, in order to be able to withstand operation in the rotation speed range higher than the engine rotation speed range. Unlike the conventional internal combustion engine, which is composed of components requiring high rigidity and high strength, the internal combustion engine can be constituted by components having relatively low rigidity and strength.

In this way, since the required city output is obtained at a lower engine speed than that of the conventional internal combustion engine, the friction loss power during the city output is reduced even at a high rotation speed range of the rotation speed range in which the internal combustion engine is operated by the present invention. The net power output is increased, whereby the net fuel consumption rate is improved, and the fuel consumption rate of the internal combustion engine with high operating frequency in the high rotation speed range is improved. Further, in the present invention, since the internal combustion engine is operated in the engine rotational speed range having a lower high rotational speed range than that of the conventional internal combustion engine, the internal combustion engine can be constituted by a component having a relatively low rigidity and strength. As a result, the internal combustion engine can be reduced in weight, and the fuel consumption rate is also improved.

In the method for operating the reciprocating internal combustion engine, the engine rotation speed range when the first predetermined rotation speed is set as an upper limit is divided into three and divided into a low rotation speed range, a medium rotation speed range, and a high rotation speed range. The predetermined rotation speed may be a rotation speed belonging to the medium rotation speed range or the low rotation speed range.

Thereby, the engine rotational speed becomes a rotational speed which is significantly lower than the engine rotational speed when the maximum city output of the conventional internal combustion engine occurs, and thus the frictional loss during the city output in the high rotational speed range including the second predetermined rotational speed. The power also decreases significantly compared with the conventional internal combustion engine, and the net power increases. In addition, since the internal combustion engine is operated in the engine rotational speed range having a significantly lower high rotational speed range than the conventional internal combustion engine, the internal combustion engine can be further constituted by components having low rigidity and strength.

The internal combustion engine may be connected to a manual transmission having a plurality of transmission stages, and the second predetermined rotational speed may be set to correspond to the respective transmission stages of the manual transmission. In this way, since the second predetermined rotational speed is set corresponding to each shifting stage of the manual transmission, after the driving force for each shifting stage is secured, the second predetermined rotational speed is changed by changing the second predetermined rotational speed at each shifting stage. The driving force at the time of up can be arbitrarily changed. As a result, the change of the driving force at the time of shift-up can be made smooth, and smooth acceleration operation can be implement | achieved. In addition, it becomes easy to secure the driving force for the vehicle models 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 in this way, fuel consumption becomes small compared with the case where control of an ignition characteristic and a engine output are reduced, for example. In addition, the output reduction means can be performed by changing or controlling the ignition characteristic. The change or control of the ignition characteristic may cause the ignition timing to be delayed or advancing at an optimal timing, but may also include stopping or omitting ignition.

The internal combustion engine includes a rotational speed sensor for detecting the engine speed, an output reduction means for lowering the engine output, and a control means, wherein the control means includes the first predetermined engine speed detected by the rotational speed sensor. When exceeding the second predetermined rotational speed less than the rotational speed, it is possible to lower the engine output of the internal combustion engine by the output lowering means.

The internal combustion engine is a vehicle internal combustion engine, and the internal combustion engine has a crank shaft and an oscillation clutch having a clutch outer member coupled to the crank shaft, the oscillating clutch having a clutch when a predetermined engine rotation speed is exceeded. It is possible to make a trailing centrifugal clutch having a clutch shoe composed of a swingable centrifugal weight against the outer member.

In the trailing centrifugal clutch, since the center of gravity of the clutch shoe is behind the support shaft in the rotational direction of the crankshaft, the frictional force is applied when the clutch shoe is in contact with the clutch outer member when the clutch shoe is not connected. It acts to swing the shoe radially inward. Therefore, the change in the magnitude of the pressing force of the clutch shoe against the clutch outer member becomes smaller than that of the leading type, and the decrease in the number of revolutions of the crankshaft due to the increase in the pressing force, that is, the increase of the load acting on the clutch shaft, The fluctuation range of the rotational speed due to the repetition of the increase in the rotational speed of the crankshaft due to the decrease in the pressing force of the clutch shoe against the clutch outer member of the clutch shoe due to the decrease in the rotational speed thereof, i. have.

As a result, abnormal vibration can be reduced, and the excitation force with respect to a vehicle by the abnormal vibration which generate | occur | produces becomes small, and the discomfort of the rider by the transmitted vibration is reduced. Further, even when the engine speed at the time of clutch connection is low, when the weight of the clutch shoe is increased or when the clutch shoe is enlarged, the abnormal vibration can be reduced after securing an appropriate clutch capacity.

The reciprocating internal combustion engine includes a driven member connected to the crankshaft and rotationally driven by the starter motor, interposed between the crankshaft and the driven member and having a one-way clutch having an outer race, wherein the outer race includes the outer race. A flywheel that can be detachably coupled to the engaging portion of the rotor of the alternator that rotates integrally with the crankshaft and extends radially outward from the engaging portion, thereby adjusting the rotational inertia mass.

As a result, a flywheel can be added and installed, avoiding enlargement of an internal combustion engine, and the rotational change of a crankshaft can be suppressed further. In addition, since the outer race constituting the flywheel is detachable from the rotor of the alternator, the rotational inertia mass of the flywheel can be adjusted simply by replacing only the outer race, thereby facilitating the degree of suppression of rotational fluctuation. I can adjust it.

The outer race can be configured to have a maximum width in the axial direction outward from a predetermined diameter, and the engaging portion, which is one end in the axial direction of the rotor of the alternator, is fitted inside the predetermined diameter to have a concave portion. By doing in this way, the rotational inertia mass can be increased, and in addition, since the engaging portion, which is one end in the axial direction of the rotor of the alternator, fits into the concave portion of the outer race, the outer race and the rotor The dimension in the axial direction at the time of combining the electrons can be reduced.

As a result, after avoiding enlargement of the internal combustion engine, the rotational inertia mass can be increased, and a flywheel effective for suppressing rotational fluctuations can be constituted. In addition, since the engaging portion, which is one end in the axial direction of the rotor of the alternator, fits into the recess of the outer race, the dimension in the axial direction when the outer race and the rotor are combined becomes smaller than the predetermined diameter. In this respect, the enlargement of the internal combustion engine can be avoided.

In addition, in this specification, an "axial direction" means the direction of the rotation axis of a crankshaft, and a "diameter direction" means the radial direction centering on the rotation axis of a crankshaft.

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

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

3 is an enlarged plan sectional view of an essential part of FIG. 2.

4 is a view taken in the direction of arrow IV when the side plate of the alternator and the one-way clutch is removed in FIG.

FIG. 5 is a view taken in the direction of arrow V in FIG. 2 when the drive plate is removed.

FIG. 6 is a graph showing the performance curve of the internal combustion engine of FIG. 1 and the performance curve of a conventional internal combustion engine.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 6.

As shown in Fig. 1, the reciprocating engine internal combustion engine 1 to which the present invention is applied is mounted on an automatic two-wheeled vehicle, and is an overhead camshaft four-cycle reciprocating internal combustion engine of a single cylinder, which is a main part configuration diagram. 1 and 2, in the spark ignition type and water cooling type internal combustion engine 1, the cylinder 3, the cylinder head 4, and the head cover (not shown) are sequentially assembled on the upper end of the crank case 2. Become one. The crankshaft 5 is rotatably supported by the crankshaft 5 via a pair of main bearings 18 and 19, and the reciprocating motion of the piston 6 slidably fitted into the cylinder 3 is connected. The rod 7 is converted into the rotational movement of the crankshaft 5.

In FIG. 2, the drive sprocket 30, the starter driven gear 62, and the alternator are formed at the left shaft end extending from the main bearing 18 of the crankshaft 5 to the left to the left from the main bearing 18 side. 31 are sequentially installed. The drive sprocket 30 is integrally coupled to the crankshaft 5, and the cam sprocket 33 is integrally coupled to the camshaft 32 rotatably supported by the cylinder head 4, and the drive sprocket 30 is integrated. ) And the cam sprocket 33, the timing chain 34 is interposed, and the camshaft 32 is rotationally driven at the rotation speed of 1/2 of the crankshaft 5. In addition, at the left end of the camshaft 5, a coolant pump 36 which is driven and coupled to the camshaft 32 via a magnetic coupling 35 using permanent magnets is provided.

3 and 4, in the pinion gear 60a of the starter motor 60, the starter driven gear 62 as the driven member which is rotationally driven through the reduction gear 61 is the boss portion 62a. It is rotatably supported by the crankshaft 5 through a plurality of needles 63 arranged on the inner circumferential surface of the crankshaft 5 and the outer circumferential surface of the crankshaft 5. The starter driven gear 62 is coupled to the crankshaft 5 via a known cam type one-way clutch 64. That is, the outer race 66 described later of the one-way clutch 64 is formed of the alternator 31 by three bolts B that are screwed into the three screw holes H formed in the outer race 66. It is fastened to the rotor 31b which rotates integrally with the crankshaft 5.

The one-way clutch 64 includes a plurality of roller-type cams 67 and cams 67 having an annular boss portion 62a as the inner race 65, a cam surface disposed between the annular outer race 66, and the cam 67. Retainer 68 (FIG. 4) holding each other at predetermined intervals, a pair of side plates 69 and 70 for restricting movement in the axial direction of each cam 67, and each cam 67; It has a spring 71 connected to it.

Thus, at start-up, rotation of the starter motor 60 is transmitted from the pinion gear 60a to the starter driven gear 62 via the reduction gear 61, and the one-way clutch 64 and the rotor 31b are transferred. It is transmitted to the crankshaft 5 through, and the crankshaft 5 is driven to rotate. Then, when the internal combustion engine 1 starts rotating the magnetic force and the rotation speed of the crankshaft 5 becomes higher than the rotation speed of the starter driven gear 62, the crankshaft 5 from the crankshaft 5 to the steered driven gear 62. Rotational transmission is interrupted by the one-way clutch 64.

The alternator 31 includes a stator 31a fixed to the generator cover 37 and a cup-shaped rotor 31b surrounding the outer side of the stator 31a and integrally coupled to the crankshaft 5. do. The rotor 31b has a boss 31c coupled to the crankshaft 5 in the rotational direction and simultaneously fastened by a nut 38 in the axial direction, and a flange portion 31c1 of the boss 31c. It has a cup-shaped magnet retainer 31d riveted to it. The outer race 66 is detachably fastened to the flange portion 31c1 as the engaging portion of the rotor 31b by the bolt B. FIG.

By the way, the outer race 66 becomes larger in the radial direction than the conventional outer race using the space existing in the radially outer side of the outer race of the conventional one-way clutch, and extends radially outward than the flange portion 31c1. Therefore, the outer race 66 extends to the vicinity of the inner circumferential surface 37a of the generator cover 37 and occupies a position where the outer circumferential surface 66a is close to the inner circumferential surface 37a. Moreover, in the cross section of the rotor 31b side in the axial direction of the outer race 66, a predetermined width in the axial direction is located at substantially the same position as the diameter in the rotation axis L of the flange portion 31c1 which is a predetermined diameter. A stepped portion 66b having a step of is formed. And in the outer race 66, the radial direction range which the outer part 66c which the width | variety in the axial direction of the outer race 66 reaches the outer peripheral surface 66a on the outer side of this step part 66b is largest. The inner side portion 66d formed over the inner side of the stepped portion 66b and whose width in the axial direction is smaller than that of the outer side portion 66c by the stepped portion is in the radial direction to the vicinity of the inner circumferential surface 66e. It is formed over the range, and the recessed part 72 in which the flange part 31c1 is fixed is formed by this step part 66b and the inner side part 66d.

Thus, the outer part 66c of the outer race 66 is located radially outward rather than the flange part 31c1, and in the axial direction which exists between the one-way clutch 64 and the rotor 31b. Using the space, the width in the axial direction can be increased, thereby making it possible to increase the mass of the outer portion 66c. Therefore, the outer race 66 is detachable to the rotor 31b of the alternator 31 which rotates integrally with the crankshaft 5, and by replacing only the outer race 66, Adjustment is possible and the flywheel for suppressing the rotational fluctuation of the crankshaft 5 is comprised.

On the other hand, on the outer periphery of the right end of the crankshaft 5 extending from the main bearing 19 to the right in FIG. 2, the crankshaft 5 is rotated coaxially with the rotation axis L of the crankshaft 5. The cylindrical member 40 supported by the said supporter is provided, and the drive gear 41 is integrally formed in the main bearing 19 side of this cylindrical member 40, and is provided in the front end part of the cylindrical member 40 at the right side. Oscillation clutch 50 is installed.

2 and 5, the oscillation clutch 50 is integrated with the cylindrical member 40 by being located outside the drive plate 51 and the drive plate 51 which rotates integrally with the crankshaft 5. It consists of a centrifugal clutch which has the cup-shaped clutch outer member 52 which rotates to The clutch shoes 54 made of three centrifugal weights are rotatably supported by three support shafts 53 fixed to the drive plate 51, respectively. Each clutch shoe 54 has a lining 55 made of a friction material on its outer surface, and the center of the clutch shoe 54 is in the rotational direction A of the crankshaft 5 rather than the position of the support shaft 53. It is arrange | positioned so that it may be located rearward, and at the time of connection of the oscillation clutch 50, a frictional force acts to rock the clutch shoe 54 radially inward. Therefore, this centrifugal clutch is a so-called trailing centrifugal clutch.

The oscillation clutch 50 is configured to connect when the engine speed N exceeds a predetermined speed. That is, when the engine speed N exceeds the predetermined engine speed, the clutch shoe 54 is radially centered about the support shaft 53 against the elastic force of the clutch spring 56 by the centrifugal force generated. It oscillates outward and makes contact with the inner circumferential surface of the clutch outer member 52 via the clutch lining 55, so that connection of the oscillation clutch 50 is started, and soon the drive plate 51 and the clutch outer member 52 It rotates integrally, and the oscillation clutch 50 will be in a fully connected state.

In addition, the oscillation clutch 50 has a conventional centrifugal force in the clutch shoe 54 so that a relatively large centrifugal force capable of securing a clutch capacity capable of transmitting a certain torque can be generated even when the engine speed N of the internal combustion engine 1 is low. The clutch shoe 54 is larger than that of the internal combustion engine, or the clutch shoe 54 having a larger mass is provided.

The driven gear 43 meshing with the drive gear 41 is rotatably supported by the main shaft 44 of the manual transmission M, which is an always-engaged gear transmission, and the driven gear 43 is a main gear. The shaft 44 is drive-connected to the clutch outer member of the transmission clutch C provided in the right end portion projecting from the crank case 2 to the right side (perspective in FIG. 2) through a damper. The shift clutch C is a friction type multi-plate clutch having a plurality of clutch plates in which friction joining or disengaging is performed by a release mechanism operated by a driver. When a plurality of clutch plates are frictionally bonded by elastic force, the torque of the crankshaft 5 is transmitted to the clutch inner member integrally coupled with the main shaft 44 via the clutch outer member, so that the shift clutch C is connected. On the other hand, when friction joining of a plurality of clutch plates is released, transmission of torque from the clutch outer member to the clutch inner member is stopped, and the shift clutch C is brought into a non-connected state.

The manual transmission M disposed behind the crankshaft 5 in the crankcase 2 includes a main shaft 44 provided with the main gear group 45 and a counter shaft provided with the counter gear group 47 ( 46, and when the shift drum 48 is rotated by a shift operation mechanism (not shown), the shift fork engaged with the cam groove of the outer circumference of the shift drum 48 is moved on the support shaft in the horizontal direction (in FIG. 2). ), The gear of the main gear group 45 and the gear of the counter gear group 47 are properly engaged with each other, and the shift is performed.

In addition, on one side of the drive plate 51 in the axial direction, a centrifugal strainer 81 formed by being covered by the cover 80 is formed, and a flow path communicating with a main gallery (not shown) ( The foreign material mixed into the lubricating oil supplied to the centrifugal strainer 81 through 82 is separated by the centrifugal force in the centrifugal strainer 81, and the flow path 83 in which the clean lubricating oil is formed inside the crankshaft 5 is formed. ) Is supplied to lubrication points such as crank pins 5a.

Therefore, the torque of the crankshaft 5 is transmitted from the oscillation clutch 50 to the cylindrical member 40 and the drive gear 41 integrally, and consists of the drive gear 41 and the driven gear 43. It is transmitted to the manual transmission M through the primary deceleration mechanism and the shift clutch C, and the torque after the shift is transmitted from the counter shaft 46 to the rear wheel W _R through the secondary reduction mechanism (not shown). The rear wheel W _R is driven to rotate (see FIG. 1).

Referring back to FIGS. 1 and 2, in the internal combustion engine 1, an intake port communicating with the combustion chamber 8 to the cylinder head 4, which forms the combustion chamber 8 between the piston 6, respectively. (9) and the exhaust port 10, and the intake valve 11 for opening and closing the opening on the combustion chamber 8 side of the intake port 9 and the opening on the combustion chamber 8 side of the exhaust port 10. An exhaust valve 12 for opening and closing is provided. The intake valve 11 and the exhaust valve 12 are predetermined opening and closing times and lift amounts in synchronism with the crankshaft 5 by a valve device composed of a cam shaft 32 and a rocker arm (not shown). The valve opening is driven. Moreover, the spark plug 13 for igniting the mixer in the combustion chamber 8 toward 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 intake pipe 14 supplies fuel toward the intake port 9 to form a mixer. A fuel injection valve 16 is provided, while an exhaust pipe 15 is connected to an opening on the side of the cylinder head 4 downstream of the exhaust port 10.

The electronic control unit (ECU) 20, which is a control means for controlling the fuel injection amount and the ignition timing, includes a rotation speed sensor 21 for detecting the engine speed N, an opening degree sensor 22 for detecting the throttle valve opening degree, The various kinds of detection means for detecting the operation state of the internal combustion engine 1, such as the pressure sensor 23 for detecting the intake pressure downstream of the throttle valve, the temperature sensor 24 for detecting the coolant temperature, the gear position switch 25, and the like. Detection signals from the sensors 21 to 25 are inputted, and based on these detection signals, fuel is injected from the fuel injection valve 16 at an injection amount corresponding to the engine driving state, and a high voltage from the ignition coil 17 is obtained. Generation time is controlled, and the ignition plug 13 ignites the ignition timing according to the engine operation state.

Here, referring to FIG. 6 showing the performance curve at full load (when the throttle valve is fully opened) of the internal combustion engine, the internal combustion engine 1 having a set displacement amount, for example, 200 cc displacement amount, is indicated by the dashed-dotted line in FIG. 6. As shown, the maximum city output PM which is the maximum value of the dedicated output of the internal combustion engine 1 generate | occur | produces when the engine speed N is 6000 rpm which is 1st predetermined rotation speed N1. It has an output characteristic. The maximum city output PM is determined by the specifications of the members constituting the internal combustion engine 1 (path diameters of the intake and exhaust systems, diameters and lift amounts of the intake valves 11 and exhaust valves 12, compression ratios, and the like). It is decided. In addition, in FIG. 6, the curve PL of a solid line shows the friction loss power curve of the internal combustion engine 1. As shown in FIG.

And in this invention, in the internal combustion engine 1 which has the output characteristic which generate | occur | produces the maximum city output PM at this 1st predetermined rotation speed N1, the 2nd predetermined | prescribed which is less than 1st predetermined rotation speed N1. At the rotational speed N2, for example, 3500 rpm, the required city output PS, which is the maximum value of the city output required for the internal combustion engine 1, is obtained. To this end, when the engine speed N detected by the rotation speed sensor 21 (FIG. 1) exceeds the second predetermined rotation speed N2, the rotation speed sensor 21 is transferred to the electronic control unit 20. FIG. A signal is input, a series of arithmetic processing is performed according to this signal, and the signal which stops the drive of the fuel injection valve 16 by the output reduction means 26 is output to the fuel injection valve 16, and a fuel injection valve The supply of fuel at (16) is cut off, and as a result, the output of the internal combustion engine 1 falls.

The second predetermined rotation speed N2 is determined in consideration of the displacement amount and the maximum city output PM on the condition that the required city output power PS of the internal combustion engine 1 is obtained. Then, it is assumed that the internal combustion engine 1 is operated in the rotational speed range from the stop (the engine speed N is 0 (zero)) to the first predetermined rotation speed N1 as an upper limit value. The speed range is divided into three, divided into a low speed range, a medium speed range, and a high speed range, and in this embodiment, the second predetermined rotation speed N2 is in the medium speed range of the internal combustion engine 1. It becomes engine speed belonging to. This middle 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 the conventional reciprocating internal combustion engine having an exhaust amount of approximately 1/2 of the exhaust amount of the internal combustion engine 1 and generating the maximum maximum output power Pm equal to the required illustrated output PS. And a frictional loss power curve including the frictional loss power PLm among the maximum city output power Pm is shown by broken lines, respectively. 6 shows the following. That is, the engine speed at which the required city output PS of the internal combustion engine 1 is obtained, that is, the second predetermined rotation speed N2, is the rotation speed when the maximum city output Pm occurs in the conventional internal combustion engine. The frictional loss power PLM of the required city output PS of the internal combustion engine 1 is equal to or less than 1/2 of N3, and the maximum city output Pm of the conventional internal combustion engine shown by the broken line. Less than 1/2 of friction loss power (PLm). When the internal combustion engine 1 is compared with the conventional internal combustion engine, the frictional loss power PL in the city output of the same magnitude is smaller in the internal combustion engine 1 than in the conventional internal combustion engine. 6, in the internal combustion engine 1 and the conventional internal combustion engine, in the internal combustion engine 1 and the conventional internal combustion engine, the sliding portion where the mechanical friction loss occurs is the same, and the auxiliary device driving loss is reduced. The generating aids are identical.

Thus, in the internal combustion engine 1 which has the output characteristic which generate | occur | produces the maximum city output PM when the engine speed N is 1st predetermined rotation speed N1, the internal combustion engine 1 is a 1st predetermined | prescribed thing. The engine speed is less than the rotational speed N1, and the engine speed range at which the first predetermined rotation speed N1 is set as the upper limit is divided into three, divided into a low speed range, a medium speed range, and a high speed range. By the output reduction means 26 which operates when exceeding the 2nd predetermined rotation speed N2 which belongs to the medium rotational speed range at one time, than the 1st predetermined rotation speed N1 from which the maximum city output PM is obtained. At the second predetermined rotational speed N2 which is significantly lower, the required city output PS, which is the maximum city output required for the internal combustion engine 1, is obtained. In addition, since the maximum city output Pm becomes the required city output PS in the conventional internal combustion engine, the internal combustion engine 1 can generate the maximum city output PM larger than the required city output PS. Since it has the output characteristic which exists, it is an internal combustion engine with a larger displacement than the said conventional internal combustion engine. And the 2nd predetermined rotation speed N2 which the required city output PS generate | occur | produces the rotation much lower compared with the engine speed N3 when the maximum city output Pm occurs in the said conventional internal combustion engine. The frictional loss power PLM of the required city output PS is significantly reduced compared with the conventional internal combustion engine. Therefore, even when the internal combustion engine 1 is operated in the high rotational speed range of the engine rotational speed range R, the frictional loss power PL in the city output is significantly reduced than that of the conventional internal combustion engine. Since the output increases, 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 rotational speed range is high. In addition, since the internal combustion engine 1 is operated in the engine rotation speed range R having a high rotation speed range significantly lower than that of the conventional internal combustion engine, the internal combustion engine 1 has a higher rotation speed range than the engine rotation speed range R. Unlike the conventional internal combustion engine which is composed of components requiring high rigidity and high strength in order to withstand operation, the internal combustion engine 1 can be constituted by components having relatively low rigidity and strength. As a result, the internal combustion engine 1 can be reduced in weight, and the fuel consumption rate is also improved.

In addition, when the engine speed exceeds the second predetermined rotation speed N2, the output reduction means 26 cuts the fuel supplied to the internal combustion engine 1, so that the engine output is reduced by controlling the ignition timing. In contrast, the fuel consumption is reduced, and the fuel consumption rate is further improved.

In addition, although the internal combustion engine 1 is operated in the engine rotation speed range R having a significantly lower high rotation speed range than the conventional internal combustion engine, the oscillation clutch 50 and the alternator installed on the crankshaft 5 are provided. Since 31 functions as the rotational inertia mass added to the crankshaft 5, the rotational fluctuation of the crankshaft 5 of low rotation speed is suppressed, and smooth operation is attained. In addition, since the internal combustion engine 1 is operated at a lower rotation speed range than the conventional internal combustion engine, the oscillation clutch 50 is larger than that of the conventional internal combustion engine so as to ensure a reliable torque transmission even at a low rotational speed. In addition, since the centrifugal weight which has a large mass compared with the conventional internal combustion engine is provided, rotational inertia mass can be increased and the said rotation fluctuation is further suppressed.

In addition, since the oscillation clutch 50 is comprised by the trailing type centrifugal clutch, the center of the clutch shoe 54 is located behind the support shaft 53 in the rotation direction A of the crankshaft 5, When the engine speed N exceeds the predetermined engine speed, and the clutch 55 in which the lining 55 of the clutch shoe 54 abuts against the clutch outer member 52 with the oscillation clutch 50 in a non-connected state. The frictional force acts to swing the clutch shoe 54 radially inward. For this reason, the change of the magnitude | size of the pressing force with respect to the clutch outer member 52 of the clutch shoe 54 becomes small compared with the thing of a reading type | mold, and the increase of the pressing force, ie, the load acting on the crankshaft 5, is increased. The load acting on the crankshaft 5, i.e., the decrease in the rotational speed of the crankshaft 5 due to the decrease in the pressing force on the clutch outer member 52 of the clutch shoe 54 due to the decrease in the rotational speed By the repetition of the increase in the rotational speed of the crankshaft 5 due to the decrease of, the fluctuation range of the rotational speed can be reduced, the abnormal vibration can be reduced, and the excitation force for the vehicle due to the abnormal vibration generated becomes small. The discomfort of the occupant due to the vibration transmitted is reduced.

The second predetermined rotational speed N2 falls within the medium rotational speed range and is equal to or less than 1/2 of the engine rotational speed N3 when the maximum city output Pm occurs in the conventional internal combustion engine. By the rotational speed, even when the internal combustion engine 1 is operated in the engine rotational speed range R belonging to a lower rotational speed range than in the related art, the weight of the clutch shoe 54 is increased, or the clutch shoe 54 ) Can be enlarged to secure an appropriate clutch capacity, and then abnormal vibration can be reduced.

The outer race 66 of the one-way clutch 64, which couples the starter driven gear 62 to the crankshaft 5, utilizes a space existing radially outward of the outer race of the conventional one-way clutch. Since the outer race 66 is coupled to the flange portion 31c1 of the rotor 31b of the rotor 31 and extends radially outward from the flange portion 31c1, the outer race 66 constitutes a flywheel. A flywheel can be added and installed, avoiding enlargement of (1), and the rotational change of the crankshaft 5 can be suppressed further. In addition, since the outer race 66 constituting the flywheel is detachable from the rotor 31b of the alternator 31, adjustment of the rotational inertia mass of the flywheel can be simplified by replacing only the outer race 66. The degree of suppression of rotational fluctuation can be easily adjusted.

The outer race 66 enlarged in the radial direction uses a space existing in the axial direction from the radially outer side of the flange portion 31c1 of the rotor 31b than the predetermined diameter in which the step portion 66b is formed. Since it has the largest width | variety in the axial direction in the outer side part 66c formed in the outer side, the rotational inertia mass can be made larger after avoiding enlargement of the internal combustion engine 1.

Therefore, the second predetermined rotational speed N2 falls within the medium rotational speed range and is equal to or less than 1/2 the engine speed N3 when the maximum city output Pm occurs in the conventional internal combustion engine. By the number of revolutions of the internal combustion engine, even when the internal combustion engine is operated in the engine rotational speed range R belonging to a lower rotational speed range than in the prior art, the internal combustion engine is utilized by using the outer race 66 of the one-way clutch 64. After avoiding the enlargement of (1), the flywheel can be expanded, and the rotational inertia mass can be increased, and a flywheel effective for suppressing the rotational fluctuation of the crankshaft 5 can be constituted.

In addition, since the flange portion 31c1, which is one end in the axial direction of the rotor 31b of the alternator 31, fits into the recessed portion 72 of the outer race 66 inside the predetermined diameter. As long as the coupling is engaged (step difference), the dimension in the axial direction at the time of coupling the outer race 66 and the rotor 31b becomes small, and the size of the internal combustion engine 1 can be avoided even in this advantage. .

Hereinafter, only the changed configuration will be described with respect to the embodiment in which the configuration of some of the above-described embodiments is changed.

In the said embodiment, although the 2nd predetermined rotation speed N2 was rotation speed which belongs to the medium rotational speed range, the 2nd predetermined rotation speed N2 should just be less than the 1st predetermined rotation speed N1, The magnitude is mentioned above. As described above, it is determined on the basis of the displacement of the internal combustion engine 1 and the maximum city output PM, thereby also compared with the above embodiment, the degree of improvement of the fuel consumption rate and the degree of lightening of the internal combustion engine 1 are reduced. However, the same effects as those of the above-described embodiments, such as improvement of the net fuel consumption rate and weight reduction of the internal combustion engine 1, are exhibited.

1, the gear position switch 25 which detects the shift position of the manual transmission M is provided, and the 2nd predetermined rotation speed N2 makes the shift stage from 1 speed to 4 speeds. It may be set corresponding to each shift stage of the manual transmission M which it has. At that time, the second predetermined rotational speed N2 has the largest second predetermined rotational speed N2 at the first speed with the largest reduction gear ratio so that the driving force required at each speed change stage is secured, and as the reduction gear ratio becomes smaller, , So that the second predetermined rotational speed N2 at each speed change stage is sequentially lowered.

By doing in this way, since the 2nd predetermined rotation speed N2 is set corresponding to each shifting stage of the manual transmission M, after a drive force for every shifting stage is ensured, a 2nd predetermined rotational speed at each shifting stage is secured. By changing (N2), the driving force at the time of shift-up can be changed arbitrarily, and by this, the change of the driving force at the time of shift-up can be made smooth, and smooth acceleration operation can be implement | achieved. In addition, it becomes easy to secure the driving force for the vehicle models having gears with different reduction ratios and to adjust the driving force change at the time of shift up.

In the above embodiment, the output lowering means 26 controls the fuel injection valve 16 to cut the fuel, but the fuel injection amount may be reduced, and the ignition timing is greatly delayed at the optimum ignition timing. Alternatively, the engine output of the internal combustion engine 1 may be lowered by the forward angle or by stopping or eliminating ignition. When the output reduction means 26 reduces the fuel injection amount, the delay angle or the forward angle of the ignition timing, and the ignition is omitted, the decrease in the output when the second predetermined rotation speed N2 is exceeded As shown by the dashed-dotted line in FIG. 6, the fuel cell becomes smoother than when the fuel is cut, and in these cases, the maximum rotation speed can be regulated by stopping the fuel cut or ignition.

When the displacement amount of the internal combustion engine 1 is large and the required city output PS is small, the second predetermined rotational speed N2 is the engine rotational speed range when the first predetermined rotational speed N1 is the upper limit. It is also possible to set it as the engine speed N which belongs to a low rotational speed range. In addition, the internal combustion engine 1 may be a multi-cylinder, and a vehicle may be a vehicle other than an automatic two-wheeled vehicle.

In the above embodiment, the recess 72 is formed in the outer race 66, but the recess 72 may be omitted, and the predetermined diameter is a flange portion 31c1 of the boss 31c of the rotor 31b. ), But may be larger than the diameter of the flange portion 31c1.

Claims (9)

In a reciprocating internal combustion engine having an output characteristic of generating a maximum urban output which is the maximum value of the urban output at full load when the engine rotational speed is the first predetermined rotational speed, The internal combustion engine includes a rotation speed sensor for detecting the engine speed and an output reduction means for lowering the engine output. The output reduction means includes the internal combustion engine at a second predetermined rotation speed less than the first predetermined rotation speed. The internal combustion engine when the engine speed detected by the rotation speed sensor exceeds the second predetermined rotation speed so that a required city output smaller than the maximum city output is obtained with the maximum city output at all times required for the full load. The engine power of the engine is lowered, and the second predetermined rotational speed is divided into three engine rotational ranges when the first predetermined rotational speed is the upper limit and divided into a low rotational range, a medium rotational range, and a high rotational range. A method of operating a reciprocating internal combustion engine, characterized in that the engine speed in the full range or the low rotation range. A reciprocating internal combustion engine having an output characteristic for generating a maximum urban output which is the maximum value of the urban output at full load when the engine rotational speed is the first predetermined rotational speed, The internal combustion engine includes a rotation speed sensor for detecting the engine speed and an output reduction means for lowering the engine output. The output reduction means includes the internal combustion engine at a second predetermined rotation speed less than the first predetermined rotation speed. The internal combustion engine when the engine speed detected by the rotation speed sensor exceeds the second predetermined rotation speed so that a required city output smaller than the maximum city output is obtained with the maximum city output at all times required for the full load. The engine output of the reciprocating internal combustion engine, characterized in that the engine output of the reciprocating internal combustion engine has the same output as that of the reciprocating internal combustion engine having a displacement of about 1/2 of the displacement of the internal combustion engine. The method according to claim 1 or 2, The internal combustion engine is mounted in a vehicle provided with a manual transmission, and the second predetermined rotational speed is the highest at one speed having the largest reduction ratio corresponding to each shift stage of the manual transmission, and sequentially as the reduction ratio decreases. A method of operating a reciprocating internal combustion engine, characterized in that it is set to be lowered. A reciprocating internal combustion engine having an output characteristic for generating a maximum urban output which is the maximum value of the urban output at full load when the engine rotational speed is the first predetermined rotational speed, The internal combustion engine includes a control means, a rotation speed sensor for detecting the engine speed, and an output reduction means for lowering the engine output, and the control means includes a first predetermined engine speed detected by the rotation speed sensor. The engine output of the internal combustion engine is lowered by the output lowering means when the required city output, which is the city output of the full load required for the internal combustion engine, is less than the rotational speed, to be obtained. 2 The predetermined rotational speed falls into the middle rotation range or the low rotational range when the engine rotational range when the first predetermined rotational speed is set to an upper limit is divided into three, and divided into the low rotational range, the medium rotational range, and the high rotational range. A reciprocating internal combustion engine, characterized in that the engine speed. The method of claim 4, wherein The internal combustion engine is a vehicle internal combustion engine, and an oscillation clutch is coupled to the crankshaft of the internal combustion engine, and the oscillation clutch is capable of swinging against the clutch outer when exceeding a predetermined engine speed lower than the second predetermined rotation speed. A reciprocating internal combustion engine comprising a trailing centrifugal clutch having a clutch shoe composed of centrifugal weights. The method according to claim 4 or 5, A crank shaft of the internal combustion engine is coupled to a driven member which is rotationally driven by a starter motor via a one-way clutch, and the outer race of the one-way clutch is coupled to a coupling part of the rotor of the alternator which is integrally rotated with the crank shaft. A reciprocating internal combustion engine comprising a flywheel capable of adjusting a rotational inertia mass by being detachably coupled and extending radially outward from the engaging portion. The method of claim 6, The outer race has a maximum width in the axial direction outside the predetermined radius, and has a concave portion in which the engaging portion, which is one end in the axial direction of the rotor, is fitted inside the predetermined radius. Internal combustion engine. delete delete

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