JPS5862371A - Ignition device of engine equipped with supercharger - Google Patents

Abstract

PURPOSE:To make it possible to perform optimum ignition timing control in the entire load region by controlling an ignition controlling device with the pressure of supercharged air in an engine where the supercharged air from an auxiliary air intake system is increasingly supplied over set load. CONSTITUTION:The load of an engine 1 increases, an auxiliary throttle valve 20 is opened interlocking with a main throttle valve 10, a supercharger 18 is driven by a signal from an opening sensor 26, and supercharged air is supplied from an auxiliary air intake system 5 to a combustion chamber 3 in addition to fresh air from a main air intake system 2. At this time, a three-way valve 33 is switched by a signal from the opening sensor 26 to communicate a supercharging pressure interlocking passage 32b to a pressure chamber 31c, allowing the supercharging pressure of the auxiliary intake air 5 to be introduced. When the supercharging pressure rises, a diaphragm 31a displaces while compressing a spring 31n, and causes a braker plate 30a to be turned in the delay angle direction to delay ignition timing. The supercharging pressure of an auxiliary air intake system 5 rises when load increases, so that the amount of displacement of the diaphragm 31a is increased, allowing the ignition timing to be further delayed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ignition device for a supercharged engine.

Traditionally, as a type of supercharged engine, in addition to the main intake system that supplies fresh air using the engine's intake negative pressure, an auxiliary intake system equipped with a supercharger has been installed to reduce the engine load below the engine's set load. A supercharged engine that supplies fresh air from the main intake system, and at least during the compression stroke, supercharged air is supplied from the auxiliary intake system in addition to the fresh air from the main intake system when the engine load is higher than the set load. For example, JP-A-Sho, 5.5-/373
It is well known as shown in No./G.

In addition, the ignition timing of the engine must be controlled according to the engine speed and load, but normally the engine speed is controlled by centrifugal advance.
Advance angle control is performed for the load and the vacuum advance angle.

However, in the supercharged engine using the main intake system and the auxiliary intake system, the advance angle control according to the engine AM is performed by normal vacuum advance angle using the intake negative pressure of the main intake system, as in the past. If this is done, there will be a problem that the ignition timing in the supercharging region will be inappropriate. In other words, the intake negative pressure in the main intake system only fluctuates with load fluctuations until the main intake system is fully open, and it only fluctuates with load fluctuations in the supercharging region where supercharging air is supplied by the auxiliary intake system. In this case, there is no correlation, and there is almost no change when the load increases by 1 in the supercharging region, and the advance amount tends to be too thick.In view of this, the present invention Provided is an ignition device for a supercharged engine in which a control device for controlling ignition timing is controlled by the pressure of the auxiliary intake system at least in a supercharging region, and the ignition timing is optimally controlled in the entire load region. It is intended to enable this to be carried out.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 7, 1 is an engine, and 2 is a main intake boat 4 that opens into the combustion chamber 6 of the cylinder head 1a of the engine 1.
Main Uj, air system, 5 which supplies fresh air to engine 1 via
7 is an auxiliary intake system that supplies supercharging air to the engine 1 through an auxiliary intake boat 6o that also opens into the combustion chamber 6, and 7 supplies exhaust gas from the engine 1 through an exhaust boat 8 that also opens into the combustion chamber 3. This is the exhaust system that discharges the air.

In the main intake system 2, 9 is a main intake valve that opens and closes the main intake boat 4 at predetermined timing, 10 is a main main throttle valve, 12 is a fuel injection nozzle that injects fuel upstream of the main throttle valve 10;
6 is an injection control device that controls the fuel injection amount.

The injection control device 13 receives the intake air amount signal detected by the air meter 14 and the engine rotation speed signal detected by the rotation sensor 15, and calculates the fuel injection amount according to the operating state of the engine 1 based on these signals. , is configured to issue a control signal to the fuel injection nozzle 12 to inject a predetermined amount of fuel into the main intake system 2.

In the auxiliary intake system 5, reference numeral 16 controls the auxiliary intake boat 6 at a predetermined timing using a timing cam 17 (see Fig. 2).
18 is a supercharger consisting of a vane-shaped air pump inserted in the middle of the auxiliary intake passage 19, and 20 is inserted in the auxiliary intake passage 19 downstream of the supercharger 18. In the auxiliary throttle valve, the auxiliary throttle valve 20 is linked to the main throttle valve 10 by a link mechanism or the like, and opens from the closed state in conjunction with the main throttle valve 10 opening to a predetermined opening degree of 1 or more. Operated in conjunction.

The supercharger 18 is connected to the electromagnetic club Sochi 21 by the engine 1.
Driven through. That is, the driving force of the crankshaft 24, which is rotationally driven via the connecting rod 23 by the reciprocating motion of the piston 22 in the engine 1, is transmitted via the drive device 25, so that the supercharger 18 is rotationally driven, and the electromagnetic clutch The drive and stop of the supercharger 18 is controlled by the connection/disconnection operation of the supercharger 21.

The electromagnetic clutch 21 is connected or disconnected in response to the negative or negative state of the engine 1, and a signal from an opening sensor 26 that detects the opening of the auxiliary throttle valve 20 is input to the electromagnetic clutch 21. The electromagnetic clutch 21 is connected to drive the supercharger 18 when the auxiliary throttle valve 20 is open for more than a set value, that is, when the load on the engine 1 is more than the set value.

Furthermore, 27 is a relief passage that bypasses the supercharger 18, and 28 is an IJ I that is interposed in the relief passage 27.
This is the J-7 valve, which regulates the upper limit of the boost pressure downstream of the supercharger 18.

On the other hand, 29 is a control device for controlling the ignition timing, and the control device 29 is configured to be controlled by the pressure of the auxiliary intake system 5 in the supercharging region.

That is, the control device 29 is connected to the distributor 30.
The grayscale plate 60a'jk is rotated to advance or retard the ignition timing. It has a diaphragm device 31, and uses the intake negative pressure of the main intake system 2 in the non-supercharging region as the operating source of the diaphragm device 31, and uses the supercharging pressure of the auxiliary intake system 5 in the supercharging region. There is.

In the diaphragm device 31, 31aU case 3
The diaphragm 31e that partitions the inside of Ib into a pressure chamber 31c and an atmospheric chamber 31d is a rod whose base end is supported by the diaphragm 31a and whose tip is linked to the gray scale plate 30a via an arm 31f'ffi. Room 31C
A first spring 31m is compressed to a first retainer 31j that is stopped by a first stopper 31h installed upright in the center, and a second spring 31m is attached to the atmospheric chamber 31d, and a second spring 31m is installed in the atmospheric chamber 31d. The first retainer 31j is mainly locked by the stopper 31
The second spring 51n is wrapped in a thin bag.

One end of a pressure introduction passage 32 is connected to the pressure chamber 31C of the diaphragm device 31, and the other end of the pressure introduction passage 32 is connected to an intake negative pressure introduction passage 32a, a supercharging r-r:, an introduction passage, 1S2b, and the other end of the pressure introduction passage 32. A three-way valve 36 for switching the passage is installed at the branch. Intake negative pressure introduction passage 32
a is opened and connected to the main intake passage W111 immediately upstream of the main throttle valve 10, while the supercharging pressure introduction passage 32b is opened and connected to the auxiliary intake passage 19 downstream of the auxiliary throttle valve 20. The three-way valve 66 is actuated by a signal from the opening sensor 26, and in the supercharging region where the auxiliary throttle valve 20 is open, the supercharging pressure of the auxiliary intake system 5 is transferred from the supercharging pressure introduction passage 32k) to the pressure chamber. 31C.

1. In the exhaust system 7, 64 is an exhaust valve that opens and closes the exhaust port 8 at a predetermined timing, and 65 is the exhaust port 8.
This is an exhaust passage that communicates with the

The opening/closing timing of the main intake valve 9 and the auxiliary intake valve 16 is such that they open from the end of the intake stroke to the compression stroke, and close at a later time than the main intake valve 9. It supplies air.

Next, to explain the operation of the above embodiment, first, the main throttle valve 1
When the load is low and the opening degree of zero is less than the set value, the auxiliary throttle valve 20 is closed, the electromagnetic clutch 21 is disconnected, the supercharger 18 is not driven, and fresh air is supplied only from the main intake system 2. is supplied to the combustion chamber 3 by natural suction.

At this time, the three-way valve 66 communicates the negative intake pressure introducing passage 52a with the pressure chamber 31C, and the negative intake pressure of the main intake passage 11 is introduced into the pressure chamber 31c.

When the intake negative pressure is large, the diaphragm 31a is deflected while contracting the spring 31m'&EE via the first retainer 313t, rotating the grayer plate 3oa' in the advance direction to advance the ignition timing. As the opening degree of the main throttle valve 10 increases, that is, as the load increases, the intake negative pressure of the main intake system 2 decreases and approaches atmospheric pressure, and the amount of deviation of the diaphragm 31a decreases, causing the ignition timing to change. The amount of advance angle decreases (retards) as the load increases. When the diaphragm 31a is deflected in the direction of compressing the second spring 31n, the $2 retainer 31 is engaged with the second stopper 31i.

When the load of the engine 1 increases and the main throttle valve 10 is opened beyond the set value, the auxiliary throttle valve 20 starts to open in conjunction with this, and a signal from the opening sensor 26 f) Electromagnetic clutch 2
1 is connected and the supercharger IEi is driven, supercharged air is supplied from the auxiliary intake system 5 in addition to fresh air from the main intake system 2 to the combustion chamber B.

Except for that, the three-way valve 33 is switched by the signal from the opening sensor 26, and the supercharging pressure introduction passage 32b? Pressure chamber 31
The supercharging pressure of the auxiliary intake system 5 is introduced into the pressure chamber 31c. When the supercharging pressure (positive pressure) increases, the diaphragm 31a moves down while compressing the second spring 31n via the second retainer 31k, causing a gray carburetion)3.
It rotates to 0ak retard power rotation to retard the ignition timing (reduce the amount of advance). The supercharging pressure of the auxiliary intake system 5 is determined by the auxiliary throttle valve 2o.
As the opening degree of the diaphragm 31a increases, that is, as the load increases, the amount of deviation of the diaphragm 31a increases.
The ignition timing is further retarded as the load increases. Note that when the diaphragm 3ta is deviated in the direction of compressing the second spring 31nQ, the first retainer 31j is
It is locked to a stopper 31h.

Therefore, advance control can be performed to the optimum ignition timing in the entire load range from low load to high load.

In the above embodiment, seven diaphragms 31a are used.
The operating source for the diaphragm device 31 is switched between the negative intake pressure of the main intake system 2 and the supercharging pressure of the auxiliary intake system 5. More preferably, a control device having a double diaphragm device is used. However, the intake negative pressure of the main intake system 2 and the supercharging pressure of the auxiliary intake system 5 are simultaneously introduced, and the ignition timing is controlled by a combination of surface pressures. Also,
Regarding the switching operation of the three-way valve 36, in addition to the opening sensor 26 of the auxiliary throttle valve 2o, there is also one that detects the supercharging region from the supercharging pressure of the auxiliary intake system 5 and switches the switching operation. .

In addition, in the above embodiment, fuel is supplied only to the main intake line 2, but in addition to the main intake system 2, the auxiliary 1 intake system 5
Alternatively, a fuel supply device using a carburetor instead of the fuel injection nozzle 12 may be adopted.

Furthermore, although the supercharger 18 is driven by the engine 1, it may also be driven by an electric motor. ), but it may be driven all the time to control the relief amount. On the other hand, the control of the electromagnetic clutch 21 is not based on the opening sensor 26 of the auxiliary throttle valve 20, but is based on the intake negative pressure. Various signals that vary depending on the load of the engine 1, such as the following, can be adopted.

Furthermore, the above ignition device can be applied not only to reciprocating engines but also to rotary piston engines.

Therefore, according to the present invention as described above, in a supercharged engine equipped with a main intake system and an auxiliary intake system, the control device for controlling the ignition timing is controlled in the supercharging region by at least the pressure of the auxiliary intake system. By controlling the engine, it is possible to create appropriate ignition timing throughout the engine load range, including the supercharging range, and improve engine operating conditions.
The desired supercharging effect can be achieved by the main intake system and the auxiliary intake system.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is an overall configuration diagram of a supercharged engine, and FIG. 2 is a curve diagram showing valve opening/closing timing. 1...Engine, 2...Main intake system, 5...
...Auxiliary intake system, 11...Main intake passage, 18.
...Supercharger, 19 ...Auxiliary intake passage, 29
...Control device, 31...Diaphragm device, 32...Pressure introduction passage, 33...
Three-way valve.

Claims (1)

[Claims] (An auxiliary intake system is provided in addition to the main intake system, and a supercharger is installed in the auxiliary intake system. Fresh air is supplied from the main intake system when the load is less than the set load of the engine, and when the load is above the set load of the engine, the main intake system is In an engine with a supercharging plate that supplies supercharging air from an auxiliary intake system at least in the compression stroke in addition to fresh air from An ignition device for a supercharged engine, characterized in that it is configured to be controlled by pressure.