JP5831317B2 - Internal combustion engine and control method thereof - Google Patents

Description

  The present invention relates to an internal combustion engine that suppresses gear noise generated when a gear-driven balancer that suppresses vibration due to torque fluctuations of the internal combustion engine is provided, and a control method thereof.

  Currently, in order to reduce fuel consumption, downsizing of the engine displacement and reduction of the number of cylinders are actively studied and put into practical use, but the ultimate large torque refuses to realize a small-cylinder engine (internal combustion engine). It is. In general, a reciprocating engine having a small number of cylinders, particularly a reciprocating engine having three or less cylinders, has a problem of rolling vibration due to torque fluctuation.

  As a countermeasure, there is an apparatus that adds an inertia system that reverses the engine, cancels the torque reaction force generated around the crank by the torque reaction force generated in the inertia system, and reduces the rolling vibration of the engine (for example, Patent Document 1). reference). This device is a so-called heron balancer. As a device that generates an inertial system that reverses the engine with this device, there is a device that uses a generator, a device that newly adds weights, or a device that adds weights to a primary balancer.

  In addition, two balancer shafts are arranged as a rotation axis parallel to the rotation axis of the crankshaft, and a power generation drive device is arranged on at least one of them, and torque fluctuations are offset by the braking torque and drive torque of the power generation drive device. There is also an apparatus (for example, see Patent Document 2).

  However, the above-mentioned devices cause another problem due to the gear driving of the inertial system that is reverse to the engine. The engine generates torque reaction force with torque fluctuation due to intermittent combustion. In particular, the value increases as the number of cylinders decreases. As a result, the rotational fluctuation speed is generated by the torque reaction force accompanied by the torque fluctuation, and when accelerating, the tooth surface of the driven side is pressed and rotated, but at the time of deceleration, the driven side is another inertia system, The tooth surface of the gear leaves and contacts the back of the next gear. At this time, rattling noise is generated.

  And at the time of the next acceleration, it contacts with the original tooth surface and is driven. At this time, rattling noise is generated. In addition, in order to reduce rolling vibration, the flywheel is attached to the shaft on the passive side, so that the torsional vibration of the shaft and the rattling noise resonate and generate significant noise.

  The distance traveled by this tooth is the gear backlash and cannot be made zero. This phenomenon becomes more remarkable as the inertial moment on the driven side is increased in order to cancel the torque reaction force, and the hitting sound increases as the inertial moment on the driven side is increased.

British Patent Application Publication GB-A-121045 JP 2000-248958 A

  The present invention has been made in view of the above-described problems, and an object of the present invention is to reduce the vibration of the internal combustion engine and to reduce the noise generated along with the reduction of the vibration and the control method thereof. Is to provide.

  An internal combustion engine of the present invention for solving the above-described object includes a balancer that reverses the rotation of the crankshaft from the crankshaft of the internal combustion engine via a gear drive device, and a belt drive device from the balancer to the belt drive device. An internal combustion engine comprising an electric motor that reverses the rotation of the crankshaft and a flywheel attached to the rotation shaft of the electric motor, further comprising a tensioner that holds the belt tension of the belt driving device, When the tension fluctuates, the electric motor is switched from power running drive to regenerative drive, or from regenerative drive to power running drive, and rotation fluctuations of at least one of the electric motor and the flywheel rotating in reverse with respect to the rotation of the internal combustion engine are changed. And a control device that synchronizes with the rotational fluctuation of the internal combustion engine.

  According to this configuration, the primary vibration of the internal combustion engine is canceled by the gear-driven balancer, and gear noise such as rattling noise generated by providing the gear-driven balancer is reduced by driving the motor or regeneratively driving the motor. When the belt tension fluctuates, that is, when the rotation of the internal combustion engine fluctuates, the motor and the flywheel can be given rotation fluctuations synchronized with the rotation fluctuation of the internal combustion engine. The generated belt slip noise can be suppressed.

  As a result, the problem of noise generated by using a gear-driven balancer to suppress engine vibration can be solved, and vibration of the internal combustion engine can be satisfactorily suppressed. Can be achieved.

  In the internal combustion engine, the tensioner includes a pulley that can move according to the tension of the belt, and a spring that biases the pulley in the pressing direction of the belt, and the balancer rotates while accelerating. The tensioner is disposed on the loose side of the belt so as to press the pulley, and when the balancer rotates while accelerating, the control device drives the electric motor to drive the balancer and decelerates the balancer. When the motor is provided with means for regeneratively driving the motor while rotating, the driving torque of the flywheel is transmitted, the torque reaction force accompanying the torque fluctuation of the internal combustion engine is halved, and the gear rattling sound, and The slip noise of the belt can be suppressed.

  When the tensioner is placed on the loose side of the belt when the balancer rotates while accelerating, when the balancer rotates while accelerating (when the crank side rotation is positive due to fluctuations in the cycle), the tensioner causes the internal combustion engine to move to the motor side. Because the rotation fluctuation of the motor can be transmitted, power loss driving of the motor compensates for the loss of flywheel torque caused by the phase delay and reduction of the driving torque that occurs through the belt drive device. Thus, torque reaction force can be reduced and gear noise can be reduced.

  Also, when the balancer rotates while decelerating (when the crank side rotation is negative due to fluctuations in the cycle), the tensioner pulley position moves due to fluctuations in belt tension, and the belt length increases accordingly. As a result, the rotational fluctuation of the internal combustion engine is smoothed to the motor side. At this time, the regenerative driving of the electric motor causes the flywheel to synchronize with the rotational fluctuation of the internal combustion engine, so that the torque reaction force can be reduced.

  In addition, since the length of the belt is increased at this time, the force applied to the gear driving device can be reduced and the gear noise can be reduced. Further, since the flywheel is synchronized with the rotational fluctuation of the internal combustion engine, the belt slip noise can be reduced.

If the spring constant of the belt is increased or the spring constant of the elastic body is increased, the movement of the tensioner at the time of tension fluctuation can be reduced. Further, the initial tension of the belt by the tensioner is set to be larger than the force necessary for driving the moment of inertia on the electric motor side. Specifically, the initial belt tension is Fa, the moment of inertia on the motor side is Im, the radius of the first pulley rotating integrally with the balancer is rb, the radius of the second pulley on the motor side is rm, the rotational acceleration of the balancer is -ωa, When the rotational acceleration of the second pulley is ωm, the maximum value of the rotational acceleration ωm on the motor side is (rb / rm) × ωa from the pulley ratio, and can be expressed by the following formula (1).

  Further, a control method of an internal combustion engine for solving the above-described problem is driven by a gear from a crankshaft of the internal combustion engine and reversely rotated with respect to the rotation of the crankshaft, and driven by a belt from the balancer. In a control method for an internal combustion engine, comprising: an electric motor that reverses with respect to rotation of a crankshaft; a flywheel attached to the rotary shaft of the electric motor; and a tensioner that maintains the tension of the belt. In addition, the electric motor is switched from power running drive to regenerative drive, or from regenerative drive to power running drive, and rotation fluctuations of at least one of the electric motor and the flywheel rotating in reverse with respect to the rotation of the internal combustion engine are It is a method characterized by synchronizing with rotational fluctuation.

  In addition, in the above control method for an internal combustion engine, the tensioner is disposed on a loose side of the belt when the balancer rotates while accelerating, and the motor is powered when the balancer rotates while accelerating. When the balancer rotates while decelerating, the electric motor is regeneratively driven.

  According to this method, when the tensioner moves due to the tension of the belt, the belt extends and cannot transmit torque to the motor side, the motor is regeneratively driven, so that the flywheel rotates in synchronization with the internal combustion engine. Therefore, torque reaction force caused by combustion can be suppressed while preventing gear rattling noise and belt slipping noise.

  According to the present invention, it is possible to reduce vibrations of the internal combustion engine and to reduce noise such as gear noise and belt slip generated due to the reduction of the vibrations. Thereby, the downsizing which can increase the use frequency of the area | region with higher heat efficiency for a fuel consumption reduction, and can also reduce the friction of an internal combustion engine main body can be aimed at.

1 is a perspective view showing an internal combustion engine according to an embodiment of the present invention. It is the side view which showed the belt drive device shown in FIG. 1, and showed the state rotated while the balancer accelerated. FIG. 2 is a side view showing the belt drive device shown in FIG. 1 and a state in which a balancer rotates while decelerating. It is the schematic which showed control to the internal combustion engine shown in FIG. 3 is a flowchart showing the operation of the internal combustion engine of the embodiment according to the present invention. FIG. 2 is a graph comparing rotation fluctuations of the electric motor and flywheel of the internal combustion engine and the internal combustion engine shown in FIG. 1, (a) showing a state in which the electric motor is not controlled, and (b) showing a state in which the electric motor is controlled. Indicates. FIG. 2 is a schematic diagram showing the relationship between torque reaction force and moment of inertia of the internal combustion engine shown in FIG. 1.

  Hereinafter, an internal combustion engine and a control method thereof according to embodiments of the present invention will be described with reference to the drawings. In this embodiment, a diesel engine will be described as an example. However, the present invention is not limited to a diesel engine but can be applied to a gasoline engine. Note that the dimensions of the drawings are changed so that the configuration can be easily understood, and the ratios of the thicknesses, widths, lengths, and the like of the respective members and parts do not necessarily match the ratios of actually manufactured parts. In addition, arrows in the figure indicate actual operations, and white arrows indicate directions of torque and acceleration.

  First, an internal combustion engine according to an embodiment of the present invention will be described with reference to FIGS. The engine (internal combustion engine) 1 includes an auxiliary flywheel 15 and an auxiliary flywheel as shown in FIG. 1 in addition to the engine body 2, the gear drive device 11, the primary balancer 12, the belt drive device 13, and the electric motor 14. A wheel clutch (hereinafter referred to as a clutch) 16 and a tensioner 20 are provided.

  The engine body 2 includes a crankshaft 4 that converts the vertical motion of the three pistons 3a to 3c into a rotational motion, and a main flywheel 5. The engine body 2 is connected to a transmission (not shown) via the main flywheel 5, but the main flywheel 5 is not necessarily required. In this embodiment, the engine body 2 is described as an in-line three-cylinder engine, but the number of cylinders and the arrangement of the cylinders are not limited.

  The gear drive device 11 includes a drive gear 11a and a driven gear 11b. The driven gear 11b is a gear having the same diameter as that of the drive gear 11a so that the primary balancer 12 rotates in reverse at a constant speed with respect to the rotation of the crankshaft 4. Preferably, the balance with the primary balancer 12 is taken into consideration. And make it eccentric. In this embodiment, since the gear passes through only one stage of the gear drive device 11, the control of gear noise can be facilitated.

  The primary balancer 12 is disposed substantially parallel to the axis of the crankshaft 4 and rotates as described above. The primary balancer 12 rotates reversely with the crankshaft 4 at a constant speed, thereby reducing pitching vibration caused by the primary inertia couple and rolling vibration caused by the 1.5th-order torque reaction force. As this primary balancer 12, a balancer of a well-known technique can be used.

  The belt drive device 13 transmits the rotation of the first pulley 13a attached to the shaft tip of the primary balancer 12 to the second pulley 13c via the belt 13b, and at that time, with respect to the rotation of the crankshaft 4, A tensioner 20 and an idler 13d that hold the tension of the belt 13b are provided to increase the speed and transmit torque.

  As shown in FIG. 2, the tensioner 20 includes a pulley 21, a fixing portion 22, a tension arm 23, and a tension spring 24. The tensioner 20 holds the tension of the belt 13b by the pulley 21 being urged to the belt 13b by the tension spring 24, and the tension arm 23 has the fixing portion 22 as an axis by the fluctuation of the tension of the belt 13b. It is a tensioner of a known technique that rotates and moves the position of the pulley 21.

  Further, when the rotation of the crankshaft 4 is positive due to the fluctuation in the cycle, that is, when the primary balancer 12 rotates while accelerating (when the crank angular acceleration of the rotation of the crankshaft 4 is positive, The crankshaft 4 is arranged on the loose side A of the belt 13b when the acceleration in the direction of the arrow a in the drawing is shown (hereinafter, when the crankshaft 4 rotates positively).

  The side A on which the belt 13b is loosened is the side that is loosened when the crankshaft 4 rotates in the positive direction. As shown in FIG. 3, when the rotation of the crankshaft 4 is negative due to fluctuation within the cycle, that is, the primary balancer. 12 is rotated while decelerating (when the crank angular acceleration is negative, indicating acceleration in the direction of the arrow b in the figure; hereinafter, when the crankshaft 4 rotates negatively), On the contrary, this is the side on which the belt 13b is stretched.

  By increasing the spring constant of the belt 13b, that is, by using the belt 13b using an aramid fiber-based core wire with little elongation, the initial tension of the belt 13b is set to about 600N to 800N. Is the same as the torque reaction force, and moves in synchronization with the secondary rotation. Therefore, the vibration is increased by the inertial force of the pulley 21, but by increasing the spring constant of the tension spring 24, the tension of the belt 13b is increased. The moving distance of the position of the pulley 21 can be reduced.

Further, as shown in FIG. 2, the initial tension Fa of the belt 13 b by providing the tensioner 20 on the loose side A of the belt 13 b is based on the force applied to the second pulley 13 c as shown in the following formula (2). The moment of inertia on the side of the electric motor 14 is set to be larger than the force T1 required for driving.

The force T1 required for driving is calculated from the following equation (3), where Im is the moment of inertia on the motor 14 side, ωm is the angular acceleration of the second pulley 13c, and rm is the radius of the second pulley 13c. be able to.

If the slip of the belt 13b is not taken into account, the force T1 required for driving is determined from the pulley ratio of the first pulley 13a and the second pulley 13c, based on the angular acceleration of the first pulley 13a (the angular acceleration of the primary balancer). ) Is the same as -ωa, and the radius of the first pulley 13a is rb.

  Therefore, the initial tension Fa of the belt 13b by the tensioner 20 can be set on the crankshaft 4 side, that is, by the rotational fluctuation of the engine 1.

  On the other hand, the idler 13d is a fixed pulley that is provided on the side B on which the belt 13b is stretched when the crankshaft 4 rotates in the positive direction and does not move even if the tension of the belt 13b varies.

  With this configuration, the belt drive device 13 is configured such that when the crankshaft 4 rotates in the positive direction, the tensioner 20 is disposed on the loose side A of the belt 13b, thereby transmitting the rotational fluctuation of the engine 1 to the motor 14 side. can do.

  On the other hand, as shown in FIG. 3, when the crankshaft 4 rotates in a negative direction, the electric motor 14 side tries to continue to rotate at the previous angular velocity. That is, when the driven gear 11b receives the torque reaction force, the side A on which the tensioner 20 is provided becomes the side A on which the belt 13b is stretched, and the position of the pulley 21 moves due to the fluctuation in the tension of the belt 13b. The belt 13b extends instantaneously. Thereby, gear noise can be reduced by causing a part of the load to be borne by the tension of the belt 13b.

  As shown in FIG. 4, the electric motor 14 is connected to the second pulley 13 c and can be driven by power and regeneratively called a so-called generator or starter generator, and may be configured to be able to generate electric power. The auxiliary flywheel 15 transmits its drive torque to the gear drive device 11 via the second pulley 13c by connecting or disconnecting the clutch 16.

  The engine 1 also includes a crank angle sensor 17 and an ECU (control device) 18 that controls the operation of the electric motor 14 and the clutch 16. The ECU 18 is a control device called an engine control unit, and is a microcontroller that comprehensively performs electrical control in charge of controlling the engine 1 by an electric circuit.

  In this embodiment, the clutch 18 is connected to or disconnected from the ECU 18 in accordance with the operating state of the engine 1, and the motor 14 is driven by power running control or regenerative control according to the crank angular accelerations a and b. Means for controlling torque are provided. Since the motor 14 and the auxiliary flywheel 15 having a large moment of inertia are added to the engine 1, it is preferable that the clutch 16 is connected when rolling vibration of the engine 1 becomes a problem.

  The crank angular accelerations a and b are calculated by, for example, converting the rotation speed of the engine 1 calculated from a digital calculation or a measured value of the crank angle sensor 17 into a cycle, and converting the frequency into F / V conversion (pulse A method of converting the frequency into a voltage), and a method of using an analog circuit for differentiating and calculating the value.

  Next, the flowchart of FIG. 5 is shown about the method of controlling the torque reaction force of the engine 1 and controlling the noise accompanying it by carrying out power running control or regenerative control of the electric motor 14 according to the crank angular accelerations a and b. The description will be given with reference.

  First, step S11 for calculating the period λ from the calculated rotation speed N from the detection signal of the crank angle sensor 17 is performed. Next, step S12 is performed in which the period λ is F / V converted and a voltage waveform Vf which is a differential waveform thereof is calculated.

  Next, step S13 for controlling the electric motor 14 with the voltage waveform Vf is performed. At this time, when the crankshaft 4 rotates in the positive direction and the crank gear 11a rotates at the crank angular acceleration a, the electric motor 14 is driven to power, the crankshaft 4 rotates in the negative direction, and the crank gear 11a rotates in the crank angular acceleration b. When rotating at, the motor is regeneratively driven.

The torque reaction force is obtained by multiplying the moment of inertia by the crank angular acceleration. Therefore, the cycle λ (crank angular acceleration) is calculated from the detection signal of the crank angle sensor 17, and the cycle λ is F / V converted to obtain a voltage waveform Vf which is a differential waveform. When the electric motor 14 is controlled using the voltage waveform Vf, the electric motor 14 is completely synchronized with the crank angular acceleration, that is, when the electric motor 14 that rotates in reverse with respect to the rotation of the engine 1 and the clutch 16 are connected. The rotation fluctuation of the secondary flywheel 15 can be synchronized with the rotation fluctuation of the engine 1.

  According to the method shown in FIG. 5, the motor 14 can be controlled in accordance with the crank angular accelerations a and b, in other words, in accordance with the torque fluctuation of the engine 1. Force can be suppressed. In addition, since the meshing force of the gear driving device 11 can be reduced, gear noise can be suppressed.

  In addition to this method, for example, the above control method may be performed by a circuit using an F / V converter (or an apparatus called an F / V converter).

  In particular, as shown in FIG. 2, when the crankshaft 4 rotates in the positive direction, the tension of the belt 13b can be maintained by the tensioner 20 pressing the belt loose side A of the belt 13b. Thus, the rotational fluctuation of the engine 1 can be transmitted to the electric motor 14 to which the auxiliary flywheel 15 is attached, and the meshing force of the gear drive device 11 can be reduced by the above control, so that gear noise is suppressed. be able to.

  On the other hand, as shown in FIG. 3, when the crankshaft 4 rotates in a negative direction, the pulley 21 of the tensioner 20 provided on the belt tension side A of the belt 13b moves due to the tension of the belt 13b, and the belt 13b Because the length of the belt 13b becomes longer, the rotation fluctuation of the engine 1 cannot be transmitted to the motor 14 side. However, since the length of the belt 13b becomes longer, the meshing force of the gear driving device 11 is also reduced, so that gear noise is suppressed. can do.

  Further, at this time, by regeneratively driving the electric motor 14, the sub flywheel 15 can be given rotational fluctuations synchronized with the engine 1, so that slip noise caused by belt fluctuations of the belt 13b can be reduced. .

  As a result, as shown in the graph comparing the rotation fluctuation of the motor 14 and the auxiliary flywheel 15 and the rotation fluctuation of the engine 1 in FIG. 6, the tensioner 20 that holds the tension of the belt 13 b is provided and the motor 14 is not controlled. And when there is control of the electric motor 14, a big difference appears especially when rotating at the crank angular acceleration b.

  Compared to FIG. 6A, as shown in FIG. 6B, the tensioner 20 is arranged on the side A where the belt 13b is loosened when the primary balancer 12 rotates while accelerating, and the primary When the balancer 12 rotates while decelerating, if the motor 14 is driven regeneratively, the rotation fluctuation on the motor 14 side (including the auxiliary flywheel) can be synchronized with the rotation fluctuation of the engine 1. Thereby, while reducing the torque reaction force accompanying the torque fluctuation of the engine 1, the gear noise of the gear drive device 11 and the slip sound of the belt 13b which generate | occur | produce with it can be reduced.

  Next, the principle of reducing the torque reaction force of the engine 1 will be described with reference to FIG. 7 will be described assuming that the primary balancer 12 and the auxiliary flywheel 15 are combined.

Here, θ is the crank angle, T (θ) is the crank torque, _Tr is the torque reaction force, I ₁ is the moment of inertia around the crankshaft 4, Ii is the moment of inertia of the i-th rotating body 30, and g _i is i The gear ratio of the second rotating body 30 is assumed. The torque reaction force _Tr can be expressed by the following formula (5).

At this time, (I ₁ + Σg _i ² I _i ) in the denominator is the effective moment of inertia of the engine 1 and is all positive regardless of the direction of rotation. Equation (5) torque reaction from the force T _r is to be minimized by providing the _{(I 1 + Σg i I i} ) so as to minimize rotational body 30 is accelerated in the reverse rotation of the engine 1 it can.

  The denominator of Expression (5) is an effective moment of inertia around the crankshaft 4, and most of the moment is occupied by the crankshaft 4, the main flywheel 5, and a clutch pressure plate (not shown). The numerator is the product of the moment of inertia of each axis multiplied by the gear ratio or pulley ratio. If there is something that reverses, its value becomes negative, the numerator becomes smaller, and the torque reaction force becomes smaller.

  Therefore, the engine 1 of the present invention can reduce the reaction force accompanying the torque fluctuation of the engine 1 with the primary balancer 12 and the auxiliary flywheel 15.

  Next, the operation of the engine 1 according to the embodiment of the present invention will be described. First, a case where the operating state of the engine 1 is during normal traveling will be described. During normal travel, the ECU 18 is in a state where the clutch 16 is connected, and the primary balancer 12 and the auxiliary flywheel 15 rotate in reverse with respect to the rotation of the crankshaft 4. The force can be reduced. However, by driving the auxiliary flywheel 15 via the belt driving device 13, the torque for reducing the torque reaction force is reduced by the phase shift and torque reduction caused by the slip and expansion / contraction of the belt 13b.

  Therefore, when the crankshaft 4 rotates in the positive direction, the ECU 18 drives the electric motor 14 to power drive, and the torque reaction force is reduced by supplementing the drive torque that is reduced by the belt drive (hereinafter referred to as efficiency reduction). can do. At this time, among the driving torques of the auxiliary flywheel 15, the driving torque shared by the electric motor 14 is reduced, so that the meshing force of the gear driving device 11 can be reduced and gear noise can be reduced. .

  When the crankshaft 4 rotates in a negative direction, the length of the belt 13b becomes longer as the position of the pulley 21 of the tensioner 20 is moved due to a change in tension, so that gear noise can be reduced and generated accordingly. When the ECU 18 regeneratively drives the electric motor 14, the auxiliary flywheel 15 can be reduced in synchronization with the rotational fluctuation of the engine 1.

  The above operation may be performed only when the vehicle is traveling at a constant low speed where the torque fluctuation becomes significant. Moreover, you may limit at the time of the start of the engine 1 where rolling vibration becomes remarkable, and a stop. During other travels, the vibration of the engine 1 does not increase so much. For example, the clutch 16 may be disconnected to reduce the moment of inertia. Since the output of the electric motor 14 during the normal running only supplements the driving torque corresponding to the reduced efficiency, the power consumption can be reduced.

  Next, a description will be given of a case where the operating state of the engine 1 is an acceleration other than a start. At the time of acceleration, the ECU 18 is in a state where the clutch 16 is disconnected. If the operating state of the engine 1 is during acceleration, the torque reaction force is small, and the meshing force of the gear drive device 11 is also small. Therefore, the driving torque of the auxiliary flywheel 15 is not required, and by disengaging the clutch 16, it is possible to suppress an increase in the effective moment of inertia during engine acceleration, improve the acceleration performance of the engine 1, and improve fuel efficiency. it can.

  Next, a case where the operating state of the engine 1 is idle and the idle stop is not operating will be described. When idling and idling stop is not operating, the ECU 18 is in a state of disengaging the clutch 16. Since the drive torque from the crankshaft 4 is smaller than the drive torque of the auxiliary flywheel 15, the clutch 16 is disengaged to reduce the meshing force of the gear drive device 11 that drives the primary balancer 12 and to reduce gear noise. can do.

  By controlling the motor 14 by the method shown in FIG. 5 at the time of idling, the torque fluctuation of the engine 1 can be suppressed. Thereby, the rolling vibration generated at the time of idling can be reduced by driving the electric motor 14 alone.

  Furthermore, compared to power running when the clutch 16 is connected or absorption due to regenerative control, there is a possibility that the fuel consumption will deteriorate as much as the motor 14 is driven, but most idlings have idling stops in operation. There is little influence, and it operates as a kind of dual mass flywheel during idling stop, so that the total fuel consumption can be improved.

  The engine 1 can reduce vibration caused by torque fluctuations of the engine 1 by providing the primary balancer 12 and the auxiliary flywheel 15 that rotate in reverse to the rotation of the crankshaft 4. Gear noise generated by driving the next balancer 12 is generated.

  Since the clutch 16 can be disconnected and the meshing force of the gear drive device 11 can be reduced during idling that is particularly noticeable, the generation of gear noise can be suppressed. In addition, since the electric motor 14 is driven by power running or regeneratively as a torque balancer, torque reaction force can be reduced and rolling vibration can be reduced.

  In addition, during constant low-speed running where vibration due to torque fluctuation becomes significant, the clutch 16 is connected, and further, the drive torque corresponding to the reduction in efficiency that is reduced by belt driving can be compensated, so that torque fluctuation can be suppressed. In addition, at this time, since the meshing force of the gear drive device 11 is reduced by the drive torque of the electric motor 14, the generation of gear noise can be suppressed.

  In addition, when the inertia moment increased by providing the auxiliary flywheel 15 is accelerated, the increase of the effective inertia moment can be suppressed because the increase of the effective inertia moment around the crankshaft 4 can be suppressed by disengaging the clutch 16. By doing so, it is possible to suppress the deterioration in fuel consumption and the delay in acceleration response.

  In addition, the belt 13b for transmitting the rotational fluctuation of the engine 1 is provided with a tensioner 20 for maintaining the tension of the belt 13b, so that the electric motor 14 is synchronized with the rotational fluctuation of the engine 1, that is, to the crank angular accelerations a and b. Accordingly, by performing the power running drive and the regenerative drive, it is possible to reduce the torque reaction force accompanying the torque fluctuation of the engine 1 while suppressing the gear noise of the gear drive device 11 and the slip noise of the belt drive device 13.

  Due to the above-described effects, it is difficult to downsize due to the vibration problem particularly in an engine having four cylinders or less. However, by applying the present invention, the vibration problem and the vibration problem are solved. Therefore, the noise problem that has occurred can be solved, and the engine 1 can be downsized.

  As a result, the frequency of use of the region with higher thermal efficiency can be increased and the friction of the engine body can be reduced, so that fuel consumption can be reduced.

  The internal combustion engine of the present invention can suppress the vibration of the internal combustion engine with a gear-driven balancer, and can reduce gear noise and belt slip noise generated to suppress the vibration. It can be used for vehicles such as trucks equipped with diesel engines that generate large torque fluctuations.

DESCRIPTION OF SYMBOLS 1 Engine 2 Engine main body 3a-3c Piston 4 Crankshaft (crankshaft)
11 Gear drive 12 Primary balancer (balancer)
13 Belt drive 14 Motor 15 Sub flywheel (flywheel)
16 Clutch 17 Crank angle sensor 18 ECU (control device)
20 Tensioner 21 Pulley 22 Fixing part 23 Tension arm 24 Tension spring

Claims (4)

A balancer that reverses the rotation of the crankshaft from the crankshaft of the internal combustion engine via a gear drive, a motor that reverses the rotation of the crankshaft from the balancer via a belt drive, and In an internal combustion engine comprising a flywheel attached to a rotating shaft of an electric motor,
A tensioner for maintaining the tension of the belt of the belt driving device;
When the tension of the belt fluctuates, the electric motor is switched from power running drive to regenerative drive, or from regenerative drive to power running drive, and at least one of the electric motor and the flywheel rotating in reverse with respect to the rotation of the internal combustion engine An internal combustion engine comprising a control device that synchronizes rotational fluctuations with rotational fluctuations of the internal combustion engine. The tensioner includes a pulley that can move according to the tension of the belt, and a spring that biases the pulley in the pressing direction of the belt,
The tensioner is arranged to press the pulley on the loose side of the belt when the balancer rotates while accelerating,
The control device includes means for driving the motor when the balancer rotates while accelerating, and regeneratively driving the motor when the balancer rotates while decelerating. 2. An internal combustion engine according to 1. A balancer driven by a gear from a crankshaft of an internal combustion engine and reversely rotated with respect to the rotation of the crankshaft, an electric motor driven by a belt from the balancer and reversely rotated with respect to the rotation of the crankshaft, and a rotating shaft of the electric motor In a control method of an internal combustion engine comprising: a flywheel attached to the belt; and a tensioner that holds the tension of the belt.
When the tension of the belt fluctuates, the electric motor is switched from power running drive to regenerative drive, or from regenerative drive to power running drive, and at least one of the electric motor and the flywheel rotating in reverse with respect to the rotation of the internal combustion engine A method for controlling an internal combustion engine, characterized in that a rotational fluctuation is synchronized with a rotational fluctuation of the internal combustion engine. The tensioner is arranged on the loose side of the belt when the balancer rotates while accelerating,
4. The control of the internal combustion engine according to claim 3, wherein when the balancer rotates while accelerating, the electric motor is driven by powering, and when the balancer rotates while decelerating, the electric motor is regeneratively driven. Method.