JPH05141254A - Braking force control device - Google Patents

Abstract

PURPOSE:To utilize a braking mechanism, in which a battery is charged to obtain braking force by power generation-actuating an electric motor mechanism mounted on a crankshaft, for braking force of a vehicle by actuating the braking mechanism so as to increase an exhaust pressure of an engine when the battery is fully charged. CONSTITUTION:A dynamo-electric machine 3 is arranged in a turbocharger 2 and also a turbine generator 4, driven by discharged gas of the turbocharger 2 is mounted to charge a battery 5 by power generation-actuating an electric motor mechanism 6 connected to a crankshaft 13 at the time of braking a vehicle, but when the battery is fully charged, a generated output id supplied to the turbine generator 4 and the dynamo-electric machine 3 to driven them respectively with reverse rotation, and an internal pressure of an exhaust manifold is increased to increase braking force by a pumping loss of an engine 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a braking force control device for improving the efficiency of a regenerative system that uses a turbine generator to recover braking energy of a vehicle as electric power.

[0002]

2. Description of the Related Art Conventionally, as a system for recovering energy in an engine, a method has been used in which the output of a turbine generator driven by exhaust gas is transmitted to an electric mechanism connected to a crankshaft to improve engine output.

Further, there is a proposal of arranging a plurality of turbine generators of this type and adding the generated output by a conversion mechanism to efficiently supply the generated electric power to an electric motor.
No. 22 publication.

[0004]

According to the proposal disclosed in the above-mentioned publication, when the electric power supplied to the electric motor is surplus, the electric power is stored in the battery. Such an electric mechanism connected to the crankshaft is operated to generate electric power and the output is charged to the battery.However, when the battery is close to full charge, charging is impossible in both cases and the braking force is controlled. There is a problem that it cannot be used.

It is also conceivable that the energy thus recovered as electric power is passed through a resistive load to brake the vehicle, but this is inconvenient in terms of energy saving.

The present invention has been made in view of the above problems, and an object thereof is to utilize a power generation output from an electric mechanism connected to a crankshaft during braking to increase exhaust pressure of an engine to control a vehicle. It is an object to provide a braking force control device that uses power.

[0007]

In order to achieve the above object, according to the present invention, an electric mechanism is connected to a crankshaft of an engine, and when the vehicle is braked, the electric mechanism is operated to generate electric power to output to a battery. In a braking force control device for charging, a turbocharger connected to an intake / exhaust flow path of the engine and provided with a rotary electric machine on a rotating shaft, a turbine generator driven by exhaust gas of the turbocharger, and a brake pedal depending on depression of the brake pedal. There is provided a braking force control device having a rotation control means for supplying the output from the electric mechanism to the rotating electric machine and the turbine generator and rotating them in reverse to increase exhaust pressure of the engine.

[0008]

In the present invention, when the vehicle is braked, the electric power output from the electric mechanism provided on the crankshaft is supplied to the rotating electric machine and the turbine generator arranged in the turbocharger, and they are rotated in reverse to increase the internal pressure of the exhaust manifold. In addition to the braking force due to the depression of the brake pedal, the braking force increases due to the pumping loss of the piston.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. Reference numeral 1 denotes an engine, and an exhaust pipe 11 and an intake pipe 12 thereof are connected to a turbocharger 2 having a turbine 21 and a compressor 22, respectively. Compressor 22 by torque of turbine 21 driven by gas
Due to the pressurized air operation, the supercharged air is pressure-fed to the engine 1 and the engine output is improved.

Reference numeral 3 denotes a rotary electric machine attached to the rotary shaft of the turbocharger 2, which has a three-phase connection and operates as an electric motor or a generator depending on the operating state of the engine 1.
For example, when the exhaust energy has a margin in medium / high speed operation, power generation is operated to recover the exhaust energy as electric power, or at low speed / high load, the battery 5 is used as a power source and a predetermined electric power is supplied via the power converter 51. Is supplied to the compressor 22 and is electrically driven to increase the supercharging pressure and the engine torque by energizing the compressor 22.

Reference numeral 4 denotes a turbine generator, which is rotationally driven by the energy of the exhaust gas after driving the turbocharger 2 to regenerate electric power, and normally the electric power is charged to the battery 5 or supplied to an electric mechanism 6 described later. To do.

The electric mechanism 6 is a crankshaft 13 of the engine 1.
When the engine torque is assisted, power is supplied from a battery or the like to operate as an electric motor, or when the vehicle is braked, it operates as a generator to convert rotational energy into electric power to generate electric power.
It gives a braking force to.

The power converter 51 is connected to the rotating electric machine 3, the turbine generator 4, the electric mechanism 6, the battery 5 and the like, and serves as a converter capable of transmitting and receiving electric power corresponding to the ratings of these electric devices, such as an inverter and a converter. , A rectifier, a changeover switch, etc., and a control command to the power converter 51 at the time of conversion is issued from the controller 7 composed of a microcomputer, for example, to electrically drive the rotating electric machine 3 or the turbine generator 4. It is something that is said. The controller 7 is wired so that a detection signal from the depression amount sensor 72 of the brake pedal 71 or the like is input.

Reference numeral 14 denotes a switching valve disposed in the middle of the intake pipe 12, which is controlled by the controller 7 and opens the compressor side of the turbocharger 2 to the atmosphere.

Next, the operation of the present embodiment thus constructed will be described. When the driver depresses the brake pedal 71 while the vehicle is traveling, step 1 is performed as shown in the process flow chart of FIG. The signal from the depression amount sensor 72 is checked, and in the case of depression, the electric mechanism 6 connected to the crankshaft 13 performs a power generation operation and brakes, recovers the energy as electric power, and the electric power is converted into the electric power converter 51. Power is transmitted to the battery 5 via.

In this case, in step 2, it is checked whether or not the battery 5 is fully charged. If the battery 5 is fully charged, the battery cannot be charged and the power generation output is not consumed. Therefore, the braking force is not applied to the vehicle. This electric power is supplied to the generator 4 and the rotary electric machine 3, and the wirings of the three-phase connection are switched to be electrically driven in the rotation direction of the chain line shown in FIG. Therefore, the compressed air from the turbine scroll flows back through the exhaust pipe 11 to increase the pressure in the exhaust manifold and increase the pump loss due to the piston, which increases the braking force like a so-called exhaust brake.

Next, at step 4, the switching valve 14 is switched as shown in FIG. 1 to open the pressure air from the compressor 22 to the atmosphere to increase the power consumption of the rotating electric machine 3 and to supply the electricity to the electric mechanism 6 for supplying the electric power. A large braking force can be obtained by increasing the load and increasing the absorbed energy from the crankshaft 13.

Although the present invention has been described above with reference to the above-described embodiments, various modifications can be made within the scope of the gist of the present invention, for example, by omitting the arrangement of the turbine generator. Is not excluded from the scope of.

[0020]

According to the present invention as in the above embodiments,
When the vehicle is being braked, the brake pedal depression is detected, and the electric mechanism connected to the crankshaft is operated to generate electricity. If the battery cannot be charged by the generated output, the rotating electric machine and turbine generator installed in the turbocharger are used. Since the power generation output is supplied so as to rotate in the reverse direction and the pressure in the exhaust manifold is increased by the reverse rotation of each turbine, the pumping loss by the piston becomes large, and the braking force is increased.

Further, according to the present invention, since the switching valve is provided in the intake pipe from the turbocharger to the engine to release the compressed air to the atmosphere, the power consumption of the rotating electric machine is increased and the load of the electric mechanism of the crankshaft is increased. There is an advantage that the braking force to the engine is increased.

[Brief description of drawings]

FIG. 1 is a configuration block diagram showing an embodiment of the present invention.

FIG. 2 is a process flow chart showing an example of the operation of the present embodiment.

FIG. 3 is an explanatory diagram showing a rotating direction of the turbine at the time of operation in the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Engine 2 ... Turbocharger 3 ... Rotating electric machine 4 ... Turbine generator 5 ... Battery 6 ... Electric mechanism 7 ... Controller 12 ... Intake pipe 14 ... Switching valve 71 ... Brake pedal

Claims (3)

[Claims] 1. A braking force control device in which an electric mechanism is connected to a crankshaft of an engine, and when the vehicle is braked, the electric mechanism is operated to generate electric power to charge an output to a battery, which is connected to an intake / exhaust flow path of the engine to rotate. A turbocharger having a rotary electric machine on its shaft, a turbine generator driven by the exhaust gas of the turbocharger, and the output from the electric mechanism according to the depression of a brake pedal is supplied to the rotary electric machine and the turbine generator. And a rotation control means for increasing the exhaust pressure of the engine by rotating them in reverse, respectively. 2. The braking force control device according to claim 1, wherein the rotation control means for causing the reverse rotation is executed in accordance with the charge amount of the battery. 3. A switching valve for discharging compressed air to the atmosphere is provided in the middle of an intake pipe from the turbocharger to the engine, and the switching valve is controlled to switch when the output of the electric mechanism is supplied to a rotating electric machine. The braking force control device according to claim 1, which is characterized in that.