JP2000230427A - Internal combustion engine with supercharger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an internal combustion engine with supercharger designed to shorten the rise time of revolution speed without enlarging its size. SOLUTION: This internal combustion engine 1 is provided with a supercharger 12 for supplying compressed air thereto, and an electric motor 16 for driving the supercharger 12. The revolution of the internal combustion engine 1 is transmitted to the supercharger 12 via a clutch 18 which is capable of connecting/disconnecting the internal combustion engine 1 and the supercharger 12. Also, supercharged state is judged based on the operating state of the internal combustion engine 1. When it is judged to be the supercharged condition, the clutch 18 is controlled to connect the internal combustion engine 1 to the supercharger 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a supercharged internal combustion engine having a supercharger driven by an electric motor.

[0002]

2. Description of the Related Art Conventionally, as disclosed in Japanese Patent Application Laid-Open No. 9-317485, a supercharger for compressing air and supplying it to an internal combustion engine is connected to an electric motor, and the supercharger is driven by the electric motor. Pay. In addition, the knocking of the internal combustion engine is detected, and if knocking occurs, the rotation speed of the electric motor is reduced, and if not, the rotation speed of the electric motor is increased to control the supercharging pressure of the air supplied to the internal combustion engine. Thus, there has been proposed an engine in which the output of the internal combustion engine and the torque are improved by supplying the air to the internal combustion engine as much as possible to cause knocking of the internal combustion engine.

[0003]

However, in such a conventional apparatus, when supercharging is required in a region where the rotation speed of the internal combustion engine is high, the rise time is increased due to the rotational inertia resistance of the supercharger and the electric motor. As a result, there is a problem that the response of the internal combustion engine is poor. Further, if the startup time is shortened, a high-torque electric motor is required, and there is a problem that the device becomes large.

[0004] It is an object of the present invention to provide a supercharged internal combustion engine capable of shortening the time required for starting the rotation speed without increasing the size.

[0005]

In order to achieve the above object, the present invention takes the following means to solve the problem. That is, in a supercharged internal combustion engine including a supercharger that compresses air and supplies the compressed air to the internal combustion engine, and a motor that drives the supercharger, a clutch capable of connecting and disconnecting the rotation of the internal combustion engine is provided. The internal combustion engine with a supercharger is characterized in that the internal combustion engine is transmitted to the supercharger through a supercharger.

[0006] Further, a supercharging state judging means for judging whether or not a supercharging state is based on an operation state of the internal combustion engine, and when the supercharging state judging means judges the supercharging state, the clutch is disengaged. It may be configured to include acceleration control means for controlling the connection between the internal combustion engine and the supercharger. Further, the acceleration control means may control the clutch to connect the internal combustion engine and the supercharger for a preset time.

A rotation speed calculating means for calculating a target rotation speed of the supercharger from an operation state of the internal combustion engine; and a control unit for controlling the electric motor and the turbocharger using the target rotation speed calculated by the rotation speed calculation means. The acceleration control means controls the clutch, and controls the clutch according to the target rotation speed calculated by the rotation speed calculation means, and controls the internal combustion engine and the supercharger. It may be configured to be connected.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. As shown in FIG. 1, reference numeral 1 denotes an internal combustion engine mounted on a vehicle. On the upstream side of an intake system of the internal combustion engine 1, air taken into an air cleaner 2 passes through an air flow meter 4 that measures an amount of intake air, and is taken into the intake air. It is supplied to the tube 6. The intake pipe 6 is provided with a throttle valve 8 connected to an accelerator pedal (not shown) for adjusting the amount of intake air in accordance with the amount of depression of the accelerator pedal.
Is provided with a throttle sensor 10 for detecting the opening degree of the throttle valve 8.

The intake pipe 6 is connected to a supercharger 12, and is connected so that compressed air from the supercharger 12 is supplied to the internal combustion engine 1. Further, a bypass valve 14 that branches off from the intake pipe 6 and bypasses the supercharger 12 is provided, and the air in the intake pipe 6 is supplied to the internal combustion engine 1 via the bypass valve 14. ing.

A motor 16 is connected to the supercharger 12, and a pulley 20 is attached to the motor 16 via a clutch 18 (see FIG. 2). This pulley 20;
A belt 24 is stretched between a pulley 22 attached to an output shaft of the internal combustion engine 1.

Next, the above-described supercharger 12, electric motor 16,
Details of the clutch 18 will be described with reference to FIGS. In the present embodiment, the supercharger 12 is a so-called two-leaf type roots type, and a closed chamber 30 is defined by a housing 26 and a rear housing 28. A drive shaft 32 is provided through the closed chamber 30, and the drive shaft 3
2 has a bearing 34 provided on the housing 26.
Are supported rotatably.

A driven shaft 36 is provided in parallel with the drive shaft 32. The driven shaft 36 is connected to the housing 26 and the rear housing 28.
Are rotatably supported by bearings 38 and 40 provided in the boss. Pump rotors 42 and 44 are fixed to the drive shaft 32 and the driven shaft 36, respectively.

A spur gear 46 is fixed to one end of the drive shaft 32 projecting from the housing 26.
And the spur gear 48 fixed to the driven shaft 36 are meshed. A cover 49 that covers the spur gears 46 and 48 is attached to the housing 26, and the cover 49 is filled with lubricating oil.

A motor housing 50 is mounted on the rear housing 28, and a motor rear housing 52 is mounted on the motor housing 50. The drive shaft 32 passes through the motor housing 50, protrudes outside from the motor rear housing 52, and is rotatably supported by a bearing 54 provided on the motor rear housing 52.

A motor rotor 56 is attached to the drive shaft 32 in the motor housing 50, and a motor stator 58 is attached to the motor housing 50 so as to face the motor rotor 56. Motor rear housing 5
The pulley 20 is rotatably supported by the pulley 2 via a bearing 59.

A boss member 60 is fitted to the distal end of the drive shaft 32 so as to rotate integrally by spline connection or the like. An armature 64 is attached to the boss member 60 via a rubber member 62 so as to face the side surface of the pulley 20. A coil 66 is mounted on the motor rear housing 52 via a coil holder 68.

When the coil 66 is excited, the armature 64 is brought into close contact with the side surface of the pulley 20, the pulley 20 and the drive shaft 32 rotate integrally, and the clutch 18 is connected. Further, when the coil 66 is not excited, the close contact between the armature 64 and the pulley 20 is released, and the clutch 18 is disconnected.

The aforementioned air flow meter 4 and throttle sensor 10 are connected to a controller 70,
A vehicle speed sensor 72 for detecting a vehicle speed V is further connected to the controller 70. The controller 70 calculates the fuel injection amount, the ignition timing, and the like based on operating conditions such as the intake air amount, the opening degree of the throttle valve 8, and the vehicle speed V, and controls the internal combustion engine 1.

The motor 16, the bypass valve 14, and the coil 66 are connected to a supercharging controller 74,
The supercharging controller 74 controls the electric motor 16, the bypass valve 14, and the coil 66 based on operating conditions and the like input from the controller 70.

Next, the acceleration control process performed by the controller 70 and the supercharge controller 74 of the present embodiment will be described with reference to the flowchart of FIG. First, the throttle opening X detected by the throttle sensor 10 and the vehicle speed V detected by the vehicle speed sensor 72 are read (step 100). Next, a reference throttle opening Xc corresponding to the vehicle speed V is calculated (step 110). As shown in FIG. 5, the relationship between the vehicle speed V at the time of traveling at a constant ground speed and the throttle opening at that time determined as the reference throttle opening Xc is stored in advance as a map through experiments or the like. The reference throttle opening Xc is
It is calculated from the vehicle speed V at that time based on the map corresponding to FIG.

Subsequently, it is determined whether or not the throttle opening X exceeds the reference throttle opening Xc (step 1).
20). When the throttle opening X is equal to or smaller than the reference throttle opening Xc, it is determined that the vehicle is not in the supercharging state, and the bypass valve 14 is opened (step 130).

Then, the electric motor 16 is stopped (step 140), and the coil 66 of the clutch 18 is de-energized, so that the clutch 18 is disconnected (step 15).
0). As a result, the supercharger 12 is not driven, and the air that has passed through the throttle valve 8 is supplied to the internal combustion engine 1 via the bypass valve 14.

On the other hand, if it is determined that the throttle opening X exceeds the reference throttle opening Xc by executing the processing in step 120, it is determined that the engine is in a supercharging state, and the bypass valve 14 is closed (step 160). , Electric motor 1
6 is driven (step 170). And clutch 1
(Step 18)
0). The time required to start up the turbocharger 12 to a sufficient number of revolutions is previously obtained by an experiment or the like, and the time is set in advance as a fixed time for exciting the coil 66.

As a result, the armature 64 is
, The armature 64 and the pulley 20 come into close contact with each other, and the clutch 18 is connected. Therefore, the rotation of the internal combustion engine 1 is transmitted to the drive shaft 32 via the pulley 22, the belt 24, the pulley 20, the armature 64, the rubber member 62, and the boss member 60. The rotation of the drive shaft 32 causes the pump rotors 42 and 44 to rotate, so that the supercharger 12 supercharges the internal combustion engine 1.

In this embodiment, when the controller 70 determines that the throttle opening X exceeds the reference throttle opening Xc, it outputs a supercharging command signal to the supercharging controller 74. Upon receiving the supercharging command signal, the supercharging controller 74 executes the processing of steps 160 to 180. Note that the controller 70 and the supercharging controller 74 may be configured by one controller.

As shown in FIG. 6A, when the supercharging command signal is output, as shown in FIG.
Is closed, and as shown in FIG.
6 is excited. The supercharger 12 is simultaneously driven by both the internal combustion engine 1 and the electric motor 16.

Since the supercharger 12 is driven by the electric motor 16 and also by the internal combustion engine 1 via the clutch 18, as shown by the solid line in FIG. The required number of revolutions can be started up in time. For example, an internal combustion engine 1 with a displacement of 2400 cc has a capacity of 3
When the supercharger 12 of 40 cc / rev is used, the connection time is set to 0.5 seconds.

The torque received by the drive shaft 32 is
8 is obtained by adding the driving torque of the electric motor 16 to the driving torque of the internal combustion engine 1 via the motor 8. The rotation speed of the supercharger 12 gradually rises due to the rotational inertia resistance of the supercharger 12 and the electric motor 16, but is driven by the internal combustion engine 1 and the electric motor 16 to start the electric motor 16 alone (see FIG. 6).
(D) The time is shorter than the time indicated by the two-dot chain line (FIG. 6).
(The time indicated by the solid line in (d)) can be started up to the predetermined number of revolutions.

As shown by the two-dot chain line in FIG. 6E, the rise of the supercharging pressure when the electric motor 16 is started up alone, as shown by the solid line in FIG. By starting with the electric motor 16, the boost pressure rises quickly, and the vehicle accelerates with good response.

After a certain period of time, the clutch 1
8, the internal combustion engine 1 does not bear the torque for driving the supercharger 12, and the acceleration effect of the vehicle by the internal combustion engine 1 can be enhanced. In the present embodiment, execution of the processing of step 120 functions as a supercharging state determination unit, and execution of the processing of steps 160 to 180 functions as an acceleration control unit.

Next, a supercharged internal combustion engine according to a second embodiment different from the above-described embodiment will be described with reference to FIG. Note that the same members as those in the above-described embodiment are denoted by the same reference numerals, and detailed description is omitted. In the second embodiment, a rotation sensor 80 for detecting the rotation speed of the internal combustion engine 1 is provided. Then, by executing the acceleration control processing shown in FIG. 8, the throttle opening X and the vehicle speed V are read (step 100), and the reference throttle opening Xc with respect to the vehicle speed V is read.
Is calculated (step 110).

Next, it is determined whether or not the throttle opening X exceeds the reference throttle opening Xc (step 12).
0) When the throttle opening X is equal to or smaller than the reference throttle opening Xc, the bypass valve 14 is opened (step 130), and the motor 16 is stopped (step 140).
The clutch 18 is disconnected (step 150).

On the other hand, when the throttle opening X exceeds the reference throttle opening Xc, a supercharging pressure command value is calculated (step 200). The supercharging pressure command value is calculated by multiplying the difference between the throttle opening X and the reference throttle opening Xc by a constant multiple α. At this time, the supercharging pressure command value becomes larger as the internal combustion engine 1 is overloaded.

Next, the target rotation speed Nm of the electric motor 16 is calculated from the relationship shown in FIG. 9 (step 210). The target rotation speed Nm is calculated from the supercharging pressure command value and the corresponding target rotation speed from the map corresponding to FIG. 9 using the rotation speed of the internal combustion engine 1 detected by the rotation sensor 80 as a parameter.

Next, the connection time Tc of the clutch 18 is calculated (step 220). The connection time Tc is equal to the internal combustion engine 1
Is the time required to drive the supercharger 12 to reach the target rotation speed Nm, which is obtained in advance by an experiment or the like, and is stored as a map corresponding to FIG. The time required for startup is calculated from this map based on the target rotation speed Nm, and is set as the connection time Tc.

Subsequently, the bypass valve 14 is opened (step 230), and the supercharging controller 74 controls the electric motor 16 to reach the target rotation speed Nm (step 24).
0). Further, the coil 66 of the clutch 18 is connected for the connection time Tc.
, The clutch 18 is connected (step 2).
50). When the load of the internal combustion engine 1 is large, the ratio of the rotation speed of the electric motor 16 to the rotation speed of the internal combustion engine 1 is increased,
The supercharging pressure of the internal combustion engine 1 can be increased.

As a result, the supercharger 12 is driven by the internal combustion engine 1 during the connection time Tc. Therefore, even when the target rotational speed of the supercharger 12 changes, the clutch 1 is activated only at the time of startup.
8 can be connected, and the number of rotations increases quickly, and the vehicle accelerates with good response. In the second embodiment, the execution of the processing of steps 200 and 210 functions as the rotation speed calculating means, the execution of the processing of step 240 functions as the supercharging control means, and the execution of the processing of steps 220 and 250 corresponds to the acceleration control. Work as a means.

The present invention is not limited to such an embodiment at all, and can be implemented in various modes without departing from the gist of the present invention.

[0039]

As described above in detail, in the internal combustion engine with a supercharger of the present invention, since the internal combustion engine and the supercharger are connected via the clutch, the supercharger can be used without using a large motor. This has the effect that the number of revolutions can be quickly started. In addition, by judging whether or not the turbocharger is in operation and connecting the clutch in the supercharged state, even in the case of supercharging in a high rotation speed range, the rotation speed of the supercharger can be quickly started. it can. Further, by connecting the clutch for a preset time, the internal combustion engine does not continue to bear the driving of the supercharger, and the effect of accelerating the vehicle by the internal combustion engine can be enhanced. In addition, even when controlling the rotation speed of the turbocharger based on the target rotation speed calculated from the operating state, by connecting the clutch according to the target rotation speed and connecting the clutch,
Even when the target rotational speed changes, the clutch can be connected only at startup.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a supercharged internal combustion engine as one embodiment of the present invention.

FIG. 2 is a sectional view of a supercharger, an electric motor, and a clutch according to the embodiment.

FIG. 3 is a sectional view taken along the line AA of FIG. 2;

FIG. 4 is a flowchart illustrating an example of an acceleration control process performed by the controller according to the embodiment.

FIG. 5 is a graph showing a relationship between a vehicle speed and a reference throttle opening according to the embodiment.

FIG. 6 shows a supercharging command signal, bypass valve opening / closing,
4 is a timing chart of coil excitation, turbocharger rotation speed, and supercharging pressure.

FIG. 7 is a schematic configuration diagram of a supercharged internal combustion engine according to a second embodiment.

FIG. 8 is a flowchart illustrating an example of an acceleration control process performed by a control controller according to the second embodiment.

FIG. 9 is a graph showing a relationship between a supercharging pressure command value and a target rotation speed according to the second embodiment.

FIG. 10 is a graph showing a relationship between a target rotation speed and a time required for startup according to the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine 4 ... Air flow meter 6 ... Intake pipe 8 ... Throttle valve 10 ... Throttle sensor 12 ... Supercharger 14 ... Bypass valve 16 ... Electric motor 18 ... Clutch 20 ... Pulley 22 ... Pulley 24 ... Belt 32 ... Drive shaft 36 ... Driven shaft 64 Armature 66 Coil 70 Controller 72 Vehicle speed sensor 74 Supercharge controller 80 Rotation sensor

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naoki Hakamada 14 Iwatani, Shimowasumi-cho, Nishio-shi, Aichi Japan Inside the Japan Automotive Parts Research Institute (72) Inventor Yoshiaki Kondo 1-1-1, Showa-cho, Kariya-shi, Aichi Shares F-term in company Denso (reference)

Claims (4)

[Claims] 1. A supercharged internal combustion engine including a supercharger for compressing air and supplying the compressed air to an internal combustion engine, and an electric motor for driving the supercharger, wherein the rotation of the internal combustion engine can be connected and disconnected. An internal combustion engine with a supercharger, wherein the internal combustion engine is transmitted to the supercharger via a simple clutch. 2. A supercharged state judging means for judging whether or not a supercharged state is based on an operation state of the internal combustion engine; and when the supercharged state judgment means judges that the supercharged state, the clutch is disengaged. The supercharged internal combustion engine according to claim 1, further comprising acceleration control means for controlling and connecting the internal combustion engine and the supercharger. 3. The internal combustion engine with a supercharger according to claim 2, wherein said acceleration control means controls said clutch to connect said internal combustion engine and said supercharger for a preset time. organ. 4. A rotation speed calculating means for calculating a target rotation speed of the supercharger from an operation state of the internal combustion engine, and controlling the electric motor to control the supercharger with the target rotation speed calculated by the rotation speed calculation device. A supercharging control unit that drives a feeder, wherein the acceleration control unit controls the clutch and controls a time corresponding to a target rotation speed calculated by the rotation speed calculation unit.
The internal combustion engine with a supercharger according to claim 2, wherein the internal combustion engine and the supercharger are connected.