JPS603430A - Supercharge pressure adjustment device of engine - Google Patents

Abstract

PURPOSE:To realize supercharge operation only when an operator so desires and prevent increase of unnecessary fuel consumption by selecting nonsupercharge or supercharge operation by means of a manual switch. CONSTITUTION:When a manual switch 28 selects nonsupercharge, a control unit 29 excites a coil 25 and absorbs a plunger 23. Exhaust gas flows through a bypass passage 10 and is bypassed from an exhaust turbine 13. When the manual switch 28 selects supercharge, the control unit 29 intercepts excitement of the coil 25, and further intercepts communication between an exhaust manifold 7 and a bypass passage 10, then the exhaust gas drives the exhaust turbine 13. When the supercharge pressure if augmented, a waste gate valve 15 opens and the exhaust gas is bypassed to the bypass passage 10 so that rise of the supercharge pressure is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a boost pressure regulating device for an internal combustion engine equipped with an exhaust gas-driven supercharger.

A supercharged internal combustion engine has the excellent feature of generating large output with a small, lightweight, and small-capacity cylinder because the air-fuel mixture is forcibly introduced into the cylinder and combusted in an overfilled state. However, on the other hand, it has the disadvantage that the piston is likely to seize or the cylinder head may be damaged due to an increase in heat load due to high compression combustion, or due to abnormal heat generation or abnormal vibration due to the knocking phenomenon caused by this.

In order to overcome this serious drawback, a typical supercharged internal combustion engine increases the fuel ratio in the air-fuel mixture to a higher than necessary ratio, and uses the heat of vaporization of the fuel to cool the high-temperature parts. Therefore, the fuel consumption rate will inevitably deteriorate in the supercharging operation range, so it is better to save resources and operate in this range only when the driver truly desires it. From my point of view, it's good.

This invention was developed in view of the drawbacks of the conventional technology as described on paper, and it allows the driver to select between excessive driving and normal driving, and the driving state can only be changed when the throttle is fully closed. In this way, an object of the present invention is to provide an excellent supercharging pressure adjusting device that can reduce unnecessary fuel consumption without impairing safety or drivability.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below with reference to an embodiment of the invention.

In the figure, l is an internal combustion engine, 2 is an intake duct connected to an air cleaner (not shown), 3 is an intake passage, 4 is a throttle valve that regulates intake air, 5 is an intake manifold,
Reference numeral 6 indicates an injector that injects fuel at a constant ratio to the amount of intake air, 7 an exhaust manifold, 8 an exhaust passage, 9 an exhaust pipe that discharges exhaust gas to the atmosphere, and 10 bypass passages. Further, reference numeral 11 denotes a supercharger that is reversely driven by exhaust gas and supercharges intake air. , an exhaust turbine 13 driven by exhaust gas, and an intake turbine 12
and a shaft 14 that feeds the exhaust turbine 13.

Further, reference numeral 15 indicates a wasteket valve 9 which controls the exhaust gas flow according to the supply pressure, and the wasteket valve 15 is connected to a diaphragm 16. The diaphragm 1
6, a spring 18, an atmospheric chamber 19 divided by the diaphragm 16, and a pressure chamber 20. 21 is the intake passage 3 and the pressure chamber 20
22 indicates an electromagnetic control valve, and the electromagnetic control valve 22 includes a plantar 23 having a valve that controls the inflow of exhaust gas into the bypass passage 10, and a spring 24 that applies a pressing force to the plantar 23. By applying a voltage, the planter 2 is moved against the spring 24.
3 and a coil 25 that attracts the air and opens the valve. 26 is a cam directly connected to throttle part A.
7 is a switch that is closed by the cam 26 when the throttle valve is fully closed; 28 is a manual switch that allows the driver to select supercharging or non-supercharging operation; and 29 is a switch 27 to the position selected by the manual switch 28. 1 shows a control unit that controls the electromagnetic control valve 22 only when the circuit is closed, and thereafter maintains the state at 1 when the manual switch 28 is reselected and the switch 27 is closed.

The operation of the engine supercharging pressure adjusting device according to one embodiment of the present invention configured as described above will be described below.

When the manual switch 28 is in the state where non-supercharging is selected,
The control unit 29 excites the coil 25 to attract the p1 blunt gloss 23 overcoming the repulsive force of the spring 24. In such a state, the intake air flowing from the intake duct 2 passes through the intake turbine 12 and the intake passage 3, is regulated by the throttle valve 4, and is mixed with fuel injected from the injector 6 in the intake manifold 5, resulting in internal combustion. It is inhaled by I and burned. Then, the combustion exhaust gas passes through the exhaust manifold 7, the exhaust passage 10, the exhaust passage 8, and the exhaust turbine 13, and is discharged from the exhaust pipe 9 to the atmosphere.

At this time, most of the combustion exhaust gas is discharged from the bypass passage 10 with low flow resistance, so the velocity of the exhaust gas flowing out from the exhaust passage valley 8 is low and the exhaust turbine 13 rotates only at a low speed. Therefore, the intake turbine 12 does not have the ability to compress and supply intake air, and the internal combustion engine 11 operates in the same manner as a normal internal combustion engine without supercharging under any operating conditions. On the other hand, when the manual switch 28 selects supercharging, the control unit 29 cuts off the excitation of the coil 25. The plunger 23 is connected to the exhaust manifold 7 and the exhaust passage 10 by the spring 24.
communication is cut off. Therefore, the entire amount of exhaust source j passes through the exhaust passage 8, and the exhaust turbine 13 is accelerated and starts rotating at high speed. As a result, the intake turbine 12 forcibly sends intake air to the intake passage 3, and supercharging is started.

In high-load continuous operation with a large opening of the throttle valve 4, exhaust gas increases due to supercharging and the bleed air terhine 13
As the engine speed increases, the boost pressure rapidly increases due to this positive feedback loop and reaches a constant value determined by the strength and thermal conditions of the internal combustion engine 1. At this time, due to the differential pressure and force between the pressure chamber 20 communicating with the intake passage 3 and the atmospheric chamber 19 in the vibrator 21, the air 7 ram 16 moves 116 times due to the repulsive force of the spring 18, and the pulp 17 opens. The valve is operated to allow exhaust gas to flow out into the gas passage 10 and stop the increase in supercharging pressure.

As a result, the internal combustion engine 1 generates high output at a critical boost pressure determined by mechanical and thermal conditions.

Next, switching control of the manual switch 28 will be explained.

Naturally, the internal combustion engine output during non-supercharging and supercharging operation when the opening degree of the throttle valve 4 is constant is greater during supercharging operation. Therefore, if the manual switch 28 is operated while the throttle valve 4 is open,
An acceleration shock occurs when changing from non-supercharging to supercharging, and a reduction shock occurs when changing from supercharging to non-supercharging. For this reason, it is preferable to switch between non-supercharging and supercharging when the output of internal combustion regulator 1 is the same for supercharging and non-supercharging, that is, when the throttle valve 4 is fully closed. The operation is performed by a signal from a manual switch 28 that instructs supercharging or non-supercharging operation, and by a control valve 26 linked to the throttle valve 4.
Based on the signal from the switch 27 that closes when the valve is fully open, the coil 25 is energized or demagnetized only when the condition A i''J D j+n? of both signals is established, and the state is maintained thereafter. This is done by the operating control unit 29. Thus, even if the manual switch 28 is operated inadvertently, drivability and running safety are impaired, and supercharging and non-supercharging operation can be selected.

In the embodiment of the present invention, the control valve is an electromagnetically driven solenoid valve 22, but it may be driven by a motor, pneumatic pressure, or hydraulic pressure, and the switch 27 may be operated magnetically or optically. Of course, it has the same effect.

As described above, the present invention provides a manual switch that can be operated arbitrarily by the driver, and when non-supercharging operation is instructed, operates the bypass control valve to bypass exhaust gas,
The supercharging mode is virtually inactive, and when supercharging operation is instructed, the supercharger is fully operated, mainly by bypassing exhaust gas, and switching between supercharging and non-supercharging is controlled by a manual switch. Even if the slot is operated in any case, it will only be performed when the trupulp is fully closed, so
It is possible to provide an excellent supercharging pressure adjustment device that can perform supercharging operation only when the driver desires without impairing running safety or drivability, and can prevent unnecessary increases in fuel consumption.

[Brief explanation of the drawing]

The figure is a configuration explanatory diagram showing a supercharging pressure adjustment device M for an engine according to an embodiment of the present invention. 1... Internal combustion engine, 4... Throttle valve, 5...
Intake manifold, 7... Exhaust manifold, 8... Exhaust passage, 10... Bypass passage,
11...Supercharger, 22...Mold control valve, 26...Cam, 27...Switch, 28...Manual switch, 29
...control unit l-. Agent Masuo Oiwa

Claims (1)

[Claims] A supercharger that is driven by the exhaust gas flow of the engine to supercharge intake air, a bypass passage that bypasses the exhaust gas to the supercharger, a control valve that opens and closes this bypass passage, and a throttle. The control valve includes a sensor that detects whether the control valve is fully closed, a manual switch that commands opening and closing of the control valve, and a control unit that opens and closes the control valve in response to a signal from the manual switch only when the throttle is fully closed. Engine boost pressure adjustment device.