JP2849955B2 - Two-stroke engine with turbocharger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a two-cycle engine having a turbocharger which electrically drives a compressor of the turbocharger.

[0002]

2. Description of the Related Art In a so-called compound system in which a turbocharger is provided in an intake / exhaust system of an engine, a turbine is rotated by utilizing energy of exhaust gas of the engine.
The bin rotates the compressor to boost the combustion air to the engine to improve engine efficiency, and the electric-generator connected to the turbine shaft is rotated by the turbine to generate electric power using the electric-generator to store electricity. When the energy of the exhaust gas is low, the motor is driven by the motor-generator with the charged electric power at a stage where the energy of the exhaust gas is low, the compressor is driven, and the combustion air is supercharged to the engine to improve the engine efficiency. Such a system has been filed, for example, as Japanese Patent Application No. 1-282554.

[0003]

On the other hand, a two-cycle engine has an advantage that it can theoretically output twice as much as a four-cycle engine. However, in the case of a two-cycle engine, the scavenging pressure must be higher than the exhaust pressure. When the scavenging pressure is lower than the exhaust pressure, sufficient scavenging cannot be performed, and the efficiency of the two-cycle engine decreases. The compound system is intended to increase the intake pressure of the engine by operating the compressor using the energy of the exhaust gas of the engine or using electric power. Therefore, when such a compound system is applied to a two-stroke engine, it can be said that the intake pressure, that is, the scavenging pressure can be increased, which is a very convenient system.

[0004] However, a large amount of electric power is required to use the above-described motor-generator as a motor and rotate and supercharge the compressor. Furthermore, when the engine speed is low, such as during idling, the amount of power generated by the normal AC generator is small, and the amount of power stored in the power storage means is small, a problem arises in that supercharging cannot be performed. .

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem. In adopting a compound system for a two-stroke engine, even when the pressure of exhaust gas discharged from the engine is low, the compound is supplied from the compound system. An object of the present invention is to provide a two-stroke engine having a turbocharger capable of always maintaining a higher intake pressure than an exhaust gas pressure.

[0006]

In order to solve the above-mentioned problems, the present invention provides a flywheel having a comb-shaped convex pole on an outer periphery of a flywheel connected to a rotating shaft of an engine. Of a permanent magnet consisting of permanent magnets having the same pitch as the above-mentioned convex poles and being alternately magnetized to the N-pole and the S-pole in proximity to the convex pole of A stator having a coil wound around a magnetic path is provided, a rotating electric machine is constituted by the rotor and the stator, and electric power generated from the rotating electric machine is supplied to an electric motor coupled to a turbocharger to perform turbocharging. A two-stroke engine having a turbocharger characterized by energizing the rotation of the machine.

[0007]

According to the present invention, when the flywheel rotates, the teeth of the flywheel cut off the magnetic flux of the permanent magnet, so that a current is generated in the coil. The generated electric current rotates the rotating electric machine connected to the turbine shaft to assist in driving the compressor.

[0008]

An embodiment of the present invention will be described below. In FIG. 1, a turbocharger 2 is provided at a rear end of an exhaust pipe 20 provided in a cylinder head 1 of an engine, and air compressed by a compressor provided coaxially with a turbine driven by exhaust gas is provided. The air is supplied to the cylinder from the intake port 3 as combustion air. The turbocharger 2 is provided with a motor-generator 4 rotated by a turbine of the turbocharger 2. As shown in FIG. 2, a ring gear 6 is provided on the outer periphery of the flywheel 5 in a comb shape for starting the engine. Since the ring gear is usually made of carbon steel and is flame-quenched, the magnetic material has a slightly low magnetic permeability, but is not unusable. In the present invention, this ring key is used as a salient pole of the rotor 100. A stator 10 is provided on the entire circumference or a part of the outer circumference of the ring carrier 6 with a small gap therebetween. This status 10
As shown in FIG. 3, a convex pole 7 is formed inside.
These salient poles 7 are formed at the same pitch as the ring gear 6, and N
The poles and S poles are alternately magnetized. A coil 11 is wound between the salient poles 7. The controller 12 has a configuration as a microcomputer having a memory and the like, outside the central processing unit, the stator 10, the rotor 100, and the like.
A device for supplying electric power to the motor-generator or the motor-generator 4 directly connected to the turbine shaft through the conductor 50 or the conductor 51 or converting the electric power sent from the motor-generator 4 into DC. In addition to the software, it has software for engine control. 13 is a well-known rotation position sensor for checking the rotation phase of the flywheel 5, 14 is a load sensor, 15 is a rotation sensor, and 16 is a booth.
The strike sensor 17 is a power storage unit.

The operation of the embodiment constructed as described above will be described below. As long as the engine is running, the flywheel 5 rotates, and the ring gear 6 attached to the flywheel 5 also rotates. As a result, the teeth of the ring gear 6 pass through the tip of the salient pole 7 and cut off the magnetic flux of the permanent magnet.
The magnetic flux passing through each coil 11 changes in synchronization with the passage of the ring gear 7 at the tip of the salient pole 7. For this reason, a generated current flows through each coil 11.

Therefore, for example, when idling,
The exhaust pressure of the engine drops and the turbocharger 2
If the drive of the bin is not sufficient, the controller 12 detects this and drives the motor-generator 4 directly connected to the turbine shaft of the turbocharger 2 to electrically operate the compressor. The pressure of the combustion air is increased to scavenge the two-cycle engine.

[0011]

As described above in detail, according to the present invention, a plurality of permanent magnets corresponding to the teeth of the crank ring gear are provided, and a coil is wound around the magnetic path of the plurality of provided permanent magnets to provide a generator. Since the compressor of the turbocharger can be rotated by the electric power generated by the generator, extremely smooth scavenging can be realized even when the rotation speed of the two-cycle engine is low.

[Brief description of the drawings]

FIG. 1 is a schematic view showing one embodiment of the present invention.

FIG. 2 is a partially enlarged view of a rotor.

FIG. 3 is a partially enlarged view of a stator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cylinder head 2 ... Turbocharger (turbocharger) 3 ... Air supply port 4 ... Electric-generator 5 ... Flywheel 6 ... Ring gear 7 ... Convex pole 10 ... Stator 11 ... Coil 20 ... Exhaust Tube 100 ... rotor

Claims (1)

(57) [Claims] 1. A rotor comprising comb-shaped convex poles is provided on the outer periphery of a flywheel coupled to a rotating shaft of an engine, and is close to the convex pole of the rotor and has the same pitch as the convex poles. A stator having a salient pole composed of a permanent magnet alternately magnetized to an N pole and an S pole, and a coil wound around a magnetic path of the permanent magnet composed of the N pole and the S pole; A turbocharger comprising a rotor and a stator, wherein power generated from the rotating electrical machine is supplied to an electric motor coupled to the turbocharger to energize the rotation of the turbocharger. A two-stroke engine.