JPS5939927A - Engine associated with supercharger - Google Patents

Abstract

PURPOSE:To simplify the structure and to reduce the number of parts, by providing double functions of compensating the temporal drop of engine output in an instant when an electromagnetic clutch is coupled to the bypath and the air control valve and of relieving the supercharge pressure. CONSTITUTION:Upon opening of a throttle valve 26 by predetermined angle (40 deg., for example), an electromagnetic clutch 32 is coupled to start rotation of a supercharger 28 thus to open an air control valve 50. Since a supercharge control valve 44 is opened at this time, the supercharge will perform no-load operation but since the air bypassed the throttle valve 26 will flow in the direction F into the bypath 48, the engine output will temporarily increase to compensate the instantaneous engine output drop due to starting of the supercharger. When the engine rotation has exceeded over setting level while the opening of the throttle valve is larger than the setting level, the air control valve 50 is opened to flow a portion of air pressure fed by the supercharger in the direction G thus to relieve the supercharge pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a supercharged engine that is equipped with an engine dry gas 6' engine feeder in an intake system that is driven by the engine at multiple rotations via an electromagnetic clutch.

In a supercharged engine, engine performance will be inconsistent unless a larger amount of intake air is supplied than the engine requires, so the supercharger's discharge volume is designed to be larger than the required air volume. has been done. For this reason, the supercharging pressure becomes excessive when the engine rotates at high speed, so it is necessary to relieve the supercharging pressure.

The conventional IJ IJ-F mechanism is provided with a dedicated IJ IJ-F passage and a control valve inside or outside the supercharger, and is controlled so that the supercharging pressure does not exceed a set value. Therefore, special equipment and piping were required for control, making the mechanism complicated and requiring a large number of parts. Furthermore, since the control is mechanical, it is affected by the pulsating waves generated by the supercharger, making it impossible to obtain the supercharging characteristics as desired, and the accuracy of the relief pressure is poor.

The present invention does not require additional parts, has a simple structure, is electronically controllable, and has excellent relief pressure. The object of the present invention is to provide a supercharged engine equipped with a relief mechanism.

The inventor of the present invention first provided a bypass A' to the intake line to connect the supercharger and the intake throttle valve, and the bypass was equipped with an electronic air control system that controlled the airflow flowing therethrough. We proposed a supercharged engine in which a valve is provided, and this air control valve can be opened from the time when the electromagnetic clutch of the supercharger is connected until the time when the supercharger actually performs the supercharging action. (filed on July 8, 1981, patent application No. 117781-1981).

This binoyasu mechanism is equipped with an electronically controlled air control valve.
The purpose is to compensate for the temporary drop in engine output when the electromagnetic clutch is engaged and the supercharger is started.

The present invention aims to achieve the above object by utilizing this pressure/gas mechanism, and for this purpose, in addition to the above bypass function, the electronically controlled air control valve is equipped with a function that allows the supercharging pressure to exceed a set value. It is characterized by being provided with a relief function that can open the valve at certain times to relieve excess supercharging pressure. Thus, according to the invention, the electronically controlled pneumatic control valve is configured as a dual function pneumatic control valve.

This air control valve can be operated depending on the engine rotational speed and intake throttle valve opening degree in the event of excess boost pressure. Alternatively, the operation may be performed according to the supercharging pressure detected by a pressure detection means provided in the intake system.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail below with reference to the accompanying drawings.

FIG. 1 shows a spark ignition engine equipped with an electronically controlled fuel injection device and an engine drive supercharger, and the intake system of the engine is equipped with an air cleaner 10. Intake pipe 1
2, a surge tank 14, an intake manifold 16, etc. The intake manifold 16 is equipped with an intake air control unit 20 for each cylinder, which is controlled by a slave control unit (control unit) 18 with a built-in microcomputer. A predetermined amount of fuel can be injected into the intake air stream based on engine speed and other data detected based on the signal. Also,
The intake pipe 3.2 is provided with an intake throttle valve 26 linked to an accelerator pedal (not shown) to control the amount of intake air to increase or decrease engine power.

A supercharger 28 consisting of a vane type blower is installed in the intake pipe 12 upstream of the intake throttle valve 26.
8 is the conduction belt 30 and the electromagnetic club,
The engine clutch and C shaft 3
It is designed to be rotated by 4. electromagnetic club,
The opening of the throttle valve 260 is switched on and off by a control circuit 38 in response to a signal from a throttle position sensor 36 connected to the intake throttle valve 26. When this occurs, the magnetic clutch is engaged. Suction 111140 and discharge side 42 of the supercharger
A supercharging control valve 44 is provided in the intake pipe section between the two.

The supercharging control valve 44 is fully closed when the opening degree of the throttle valve 26 is a second set value, for example, 50 degrees or more, and is gradually opened when it is less than 50 degrees. 26. The operations of the electromagnetic clutch, valve 32, and supercharging control valve 44 in relation to the opening of the throttle valve 26 will be explained with reference to FIG. For example, when the angle is moved away to 40 degrees, the electromagnetic clutch is connected and the supercharger is started to rotate. At this time, since the supercharging control valve 44 is fully open, the air pumped by the supercharger is circulating from the discharge side 42 to the suction (111+40), and no supercharging pressure is generated.Next, When the throttle valve opening reaches point A (for example, 45°), link 46
The supercharging control valve 44 gradually begins to close due to the action of , and as the throttle valve further opens, the pressure increases, and when the throttle valve opening reaches 8 points (for example, 50°), the supercharging control valve 44 closes completely. It is closed and the engine is fully supercharged.

Referring again to FIG. 1, a supercharger 28 and a throttle valve 26 are connected to the intake pipe 12. A bypass 48 is provided in the air, and the bypass 48 is provided with an air control valve 50 which is controlled by the electronic control unit 18. The air control valve 50 is a flow control valve equipped with a linear solenoid,
The flow rate of the airflow flowing through the bypass can be controlled according to the flow value of the control current '1 outputted by the electronic control unit 18.

According to the invention, bypass 48 and air control valve 50 have a dual function. The first function is to compensate for a temporary drop in engine output at the moment the electromagnetic clutch 32 is engaged. For this reason, the air control valve 50 is programmed to open when the throttle valve opening is within the range of point 0 and point A in FIG. .

The second function is to relieve supercharging pressure when it becomes excessive. For this reason, ■1. Child control unit, 1
8 is based on the signals from the throttle position sensor 36 and the ignition coil 24, when the throttle valve opening reaches the second set value K (point B in diagram i2) and the engine speed exceeds the set value. The air control valve 50 is programmed to open at certain times.

Next, to explain the operation of this embodiment, when the throttle valve 26 opens by a predetermined opening degree of 0 (see FIG. 2, for example 4o6),
The throttle position sensor 36 detects this and outputs a signal to the electronic control unit 18 and the clutch/chip control circuit 38. As a result, the control circuit 38 connects the electromagnetic clutch 32 to start rotating the supercharger 28, while the electronic control unit 18 opens the air control valve 50. At this time, the supercharging control valve 44 is open, so the supercharger performs no-load operation, but a throttle valve is installed in the binox 48.
Since the cooled air flows in the direction of arrow F (xF), the engine output temporarily increases to compensate for the instantaneous decrease in engine output due to activation of the supercharger. When the throttle 9 valve opening increases and supercharging starts (point A in Figure 2), the electronic control unit
8 closes the air control valve 50 in response to a signal from the sensor 36, and when the throttle valve opening reaches point B in FIG. 2, the supercharging control valve 44 is fully closed and the supercharger is operated at full load.

As shown in FIG. 3, when the engine speed exceeds the set value N in the fully supercharged state, the supercharging pressure does not exceed the set value P, and the supercharging pressure becomes excessive. The engine speed N when the boost pressure reaches the set value P is known in advance, and this value N is recorded in the storage section of the electronic control unit ) 18. Therefore, when the engine speed detected by the signal from the ignition coil 24 exceeds the set value N and the throttle valve opening detected by the throttle position sensor 36 exceeds the set value 8, the electronic control unit (electronic control unit) 18 outputs a signal to open the air control valve 50. As a result, a portion of the air forced by the supercharger flows through the IJ path in the direction of arrow G, and the supercharging pressure is reduced. The graph in FIG. 4 shows this relief state, and relief is performed in the shaded area in the graph.

In the above-mentioned embodiment, when the boost pressure is increased, the electronic control unit 18 is configured to operate the air control valve based on the throttle valve opening and the engine speed. However, as shown in Figure 1, the intake system downstream of the throttle valve,
For example, a pressure sensor 52 may be provided in the surge tank 14, and the air control valve 50 may be controlled based on a signal from this pressure sensor.

Also, instead of the linear solenoid type air control valve 50,
It is also possible to use an on/off type air control valve.

As is clear from the above, the present invention provides a dual function to the air control valve and the air control valve for compensating for the drop in engine output when starting the supercharger, allowing them to be used in common. can be simplified and the number of parts can be reduced. Furthermore, since the air control valve is electronically controlled, it is possible to adjust the supercharging pressure IJ-IJ-f with an accuracy that matches the air amount required by the engine.

[Brief explanation of drawings]

Fig. 1 is a system diagram of an embodiment of the present invention, Fig. 2 is a graph showing the relationship between throttle valve opening and supercharging control valve opening, and Fig. 3 is a graph showing the relationship between engine speed and supercharging pressure. FIG. 4 is a graph showing the supercharging pressure relief state with respect to engine speed and throttle valve opening. 12... Intake pipe, 18... Electronic control unit, 26
...Intake throttle valve, 28...Supercharger, 32...Electromagnetic crane. H, 36...Throttle position sensor, 38...
・Cluster, child control circuit, 44... supercharging control valve, 48...
・Bypass, 50...Dual function air control valve, 52...
・Pressure sensor. Figure 1 Closed OAB Open Throttle valve opening Figure 3 Niassin rotational speed Figure 4 Enogyno rotational speed

Claims (1)

[Claims] 1. In a supercharged engine having an engine drive supercharger driven by the engine via an electromagnetic clutch in the intake system, the intake system includes a supercharger and an intake throttle valve. The bypass is provided with an electronically controlled air control valve having a dual function for controlling the airflow flowing through the bypass, and the air control valve is connected to an electromagnetic clutch. Until the supercharger actually performs the supercharging action, the throttle valve is closed as soon as the valve is opened. This allows air to flow through the pinos and be taken into the engine, and also opens the valve when the boost pressure of the supercharger exceeds the set value to prevent excess boost pressure. A supercharged engine characterized by functioning to provide relief. 2. Claim 1, wherein the air control valve operates depending on the engine speed and the opening degree of the throttle valve when the supercharging pressure is high. Supercharged engine listed. 3. The air nIU control valve operates depending on the boost pressure detected by the boost pressure detection means when the boost pressure is IJ-F. r "A supercharged engine according to claim 1.