JPS5818520A - Supercharger for internal-combustion engine - Google Patents

Abstract

PURPOSE:In a supercharger in which air sucked by an air pump is pressurized to be supplied to an engine, to enable the supply of an always appropriate quantity of air, by connecting the suction and discharge sides of the air pump to each other through a communication passage provided with a control valve and through a by-pass provided with a solenoid valve. CONSTITUTION:An air pump 1, which is selectively driven by an engine 2 through a clutch mechanism 3, is provided as a mechanical supercharger. A passage 4 on the suction side of the pump 1 and a passage 6 on its discharge side are connected to each other through a communication passage 13. A control valve 14, which is closed in the supercharged operation of the engine 2 to control the boost pressure, is provided as a recirculating valve in the passage 13. The control valve 14 is opened together with a throttle valve 11 by the depression of an accelerator pedal 10 through interlocking units 23-25. A by-pass is connected between the passages 4, 6 to detour the pump 1. A solenoid valve 20, which is opened or closed depending on the degree of opening of the control valve 9 at the time of the engagement of a clutch, is provided in the by-pass.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a supercharging device for an internal combustion engine used for forcibly feeding air into the intake system of an automobile engine such as a gasoline engine, a diesel engine, or a rotary engine. The present invention relates to a mechanical/mechanical supercharging device equipped with a driven air pump.

This type of supercharging device for internal combustion engines is effective in increasing engine output and saving fuel consumption, and has been used for quite some time, and now turbochargers using an exhaust turbine are generally used. There is. In this type of turbocharger, the engine exhaust rotates the exhaust turbine, which drives the turbine compressor and supplies air to the engine's intake system, so much of the waste is wasted. Because it uses high-temperature exhaust gas as a driving source, it has the advantage of recovering exhaust energy and eliminating excess horsepower loss.

However, in order to obtain the desired boost pressure with such a turbocharger, the engine must be operated at a fairly high rotational speed, and the supercharging effect cannot be obtained at low engine speeds. On the contrary, the result is that the engine output is insufficient. In addition, since the engine exhaust is used, it is difficult to instantaneously follow the rotation of the supercharger in response to severe fluctuations in the engine's rotation speed, resulting in a slight time delay, which can lead to insufficient engine output and reduce acceleration. Furthermore, in order to eliminate such problems, various control mechanisms are required, and heat resistance and strength are also required, which is not desirable from a cost standpoint.

On the other hand, a mechanical supercharging device using an air pump driven by the engine can obtain a supercharging effect even at low engine speeds, for example during high load and low speeds such as when driving up a hill. It is effective in improving engine output and is particularly preferred for use in automobiles. In such a mechanical supercharging device, the air pump is connected to the engine via a clutch mechanism, and this clutch mechanism is configured to operate only when supercharging is necessary, thereby providing a sufficient amount of power to drive the pump to the engine. It becomes possible to reduce the load and save on fuel consumption.

Therefore, such a mechanical supercharging device selectively performs quick and reliable supercharging only when necessary, regardless of the engine speed, increasing engine output and achieving fuel savings. Although it has the advantage of being more advantageous than a turbocharger and having a relatively simple configuration, it does cause some problems.

In other words, the above-mentioned air pump is directly connected to the engine and starts operating as soon as the clutch mechanism is turned on during supercharging operation, forcing a large amount of air into the engine's intake system, thereby increasing the boost pressure. This results in a large step-by-step increase.

And when such a sudden increase in boost pressure occurs,
It has an adverse effect on the engine's intake system and causes a sudden increase in engine output, making it undesirable for use in automobiles.

For this reason, the suction side and the discharge side of the air pump are connected via a control valve, and this control valve is not fully closed immediately after pump operation, thereby directing part of the pump discharge pressure to the suction side (of course, ) to prevent a sudden increase in boost pressure, and then sequentially close the control valves to increase boost pressure smoothly and appropriately. That is,
During normal naturally aspirated operation, this control valve is opened to supply air from the air intake directly to the engine intake system, and during supercharging operation, it is gradually closed to increase boost pressure appropriately, and then completely closed. All you have to do is close it to deliver the desired boost pressure and increase engine output. If the control valve that performs this function is connected to the throttle valve drive system so that the control valve is controlled according to the displacement of the pedal angle of the accelerator pedal operated by the driver, the driver's control will be the simplest and most reliable. It is possible to control boost pressure by communicating intentions, and since the control valve is always open and supercharging is released when the accelerator pedal is released, this is the best method for safety in an emergency. The present inventors have discovered this.

To briefly explain this using FIG. 1, reference numeral 1 in the figure is an air pump that is selectively driven by an engine 2 via a clutch mechanism 3. The intake port 5 and the discharge side are connected through a passage 6 to an intake system of the engine 2, and in the case shown, to a carburetor 7, respectively. Further, a control valve 9 is disposed in a communication passage 8 that communicates the pump suction side passage 4 and the discharge side passage 6, which is opened during natural intake operation and closed during supercharging operation to control boost pressure. There is. The control valve 9 is directly connected to the drive system of the throttle valve 11 of the carburetor 7, which is controlled to open and close in conjunction with the accelerator pedal 10, and is rotated by an amount of displacement corresponding to the depression angle of the accelerator pedal 10 to draw the pump suction. It is configured to communicate or cut off the side and the discharge side.

In addition, 12 in the figure is a sensor for operating the clutch mechanism 3.

However, if such a configuration is adopted, while the supercharging device can be operated in response to the driver's acceleration request, the opening and closing of the control valve 9 is controlled so as to obtain the desired boost pressure characteristics according to the engine characteristics. This causes a problem in that the required amount of air cannot be supplied to the intake system of the engine 2, resulting in a slight reduction in engine output.

In other words, when the clutch mechanism 3 is operated early, that is, the air pump 1 starts operating early, the timing shown in FIG.
As shown in , since the amount of depression of the accelerator pedal 10 is small and the amount of closing of the control valve 9 is small, most of the pump discharge air flows to the suction side immediately after Claratio, the boost pressure increases only slightly, and on the contrary, Air is sent to the engine with resistance, and as a result, the boost pressure necessary to output enough to cope with the pump load cannot be obtained, resulting in engine output being lower than in naturally aspirated operation, resulting in acceleration. There is a problem with delays. This is because the slight increase in boost pressure 't' + t does not affect the engine output.

Also, when the first clutch mechanism 3 operates late, the third clutch mechanism 3
As shown in Figures (a), (b), and (e), the accelerator pedal 1
0 is large and the opening degree of the control valve 9 is small, the intake resistance increases and it is difficult to maintain a sufficient amount of intake air to the engine 2 before the air pump 1 operates. The problem is that the engine output decreases.

Such a problem cannot be solved by simply connecting the control valve 9 directly to the accelerator pedal 10, which does not balance shock reduction and loss reduction immediately after the start of supercharging, and also affects the engine characteristics. It is also impossible to control the boost pressure according to the situation, so it is necessary to take countermeasures.

The present invention has been made in view of the above-mentioned circumstances, and separately from the control valve connected to the drive system of the throttle valve that connects the suction side and the discharge side of the air pump, the suction side and the discharge side of the pump can be controlled as desired. With a simple configuration that connects via a solenoid valve that is controlled to open and close by a signal, this solenoid valve adjusts the boost pressure control by the control valve, reducing the shock at the start of supercharging, and providing an appropriate and efficient system. A supercharging device for an internal combustion engine that can obtain boost pressure characteristics, thereby achieving a highly efficient supercharging effect by performing intake that matches the engine characteristics, reducing fuel consumption and improving engine output. It provides:

Hereinafter, the present invention will be explained in detail using embodiments shown in the drawings.

FIG. 4 shows an embodiment of a supercharging device for an internal combustion engine according to the present invention, in which the same or corresponding parts as in FIG. 1 are designated by the same numbers.

Now, according to the present invention, in order to properly control the boost pressure by the control valve 9 connected to the drive system of the throttle valve 11, the pump suction side and the discharge side are electromagnetically controlled separately from the control valve 9. It is characterized in that it is connected via a valve 20, and the solenoid valve 20 is controlled to open and close when necessary. That is, in such a configuration, the solenoid valve 2o
can be adjusted by operating based on the opening degree of the control valve 9 at the time of the clutch 17, so as to prevent misalignment caused by the control valve 9 opening too much or closing too much. It is composed of

In addition, 21 in the figure is a valve drive unit having an electromagnetic coil 22#,
Reference numeral 23 designates an operating disc that rotates the throttle valve 11 in accordance with the depression angle of the accelerator pedal 10, and 24 represents an operating lever that rotates the control valve 9 against a spring 25 by the operating disc 23.

In the supercharging device configured as described above, the opening and closing of the control valve 9 and the magnetic valve 20 are controlled as follows.
It becomes possible to obtain desired boost pressure characteristics.

That is, as shown in FIG. 5(a), when the control valve 9 is closed in conjunction with the accelerator pedal 10 and the clutch-on point is late, the solenoid valve 20 is closed by the clutch-on signal as shown in FIG. 5(b). By controlling from the open state to the closed state, the necessary intake air amount is maintained during naturally aspirated operation, and during supercharged operation, the desired boost pressure characteristics can be obtained by the control valve 9 as shown in the same figure (C). It becomes possible to improve the engine output as shown in FIG. 2(d).

By doing so, it is possible to save fuel consumption during naturally aspirated operation and during supercharged operation.

Of course, depending on the movement of the control valve 9, the opening and closing of the valve 2o may be controlled as shown in FIG.
Alternatively, it is possible to control the opening and closing at a later time, and to take out the signal, for example, a separate switch means or the like may be provided for the accelerator pedal 10 or a part of its drive system.

In short, the boost pressure characteristics due to the movement of the control valve 9 linked to the accelerator pedal 10 are controlled by the solenoid valve 20.
It is only necessary to make it possible to freely adjust the boost pressure, thereby obtaining appropriate boost pressure characteristics and achieving a highly efficient supercharging effect.

In addition, although the above-mentioned embodiment shows a case in which the present invention is applied to an engine having a carburetor 7, the present invention is not limited to this. For example, in a diesel engine, the carburetor 7 can be replaced with a fuel injection pump. Needless to say.

The drive system for the throttle valve 11, which is operated according to the depression angle of the accelerator pedal 1o, is not necessarily limited to the structure of the embodiment, and various modifications are possible. The position at which the sensor 12 is taken out can also be freely set within the range of the drive system.

As explained above, according to the supercharging device for an internal combustion engine according to the present invention, the control valve can be opened and closed by a desired signal separately from the control valve connected to the drive system of the throttle valve that connects the pump suction side and the discharge side. Since the suction side and the discharge side of the pump are connected through a controlled electromagnetic valve, the following excellent effects can be obtained.

(The boost pressure control by the control valve is adjusted by the function of the electromagnetic valve 11, reducing the shock and loss at the start of supercharging, and making it possible to obtain appropriate and efficient boost pressure characteristics.

(2) By performing intake according to such engine characteristics, a highly efficient supercharging effect can be obtained, which plays a major role in saving fuel consumption and improving engine output.

(3) Desired boost pressure characteristics can be obtained with a simple configuration in which a solenoid valve is combined with a control valve, so the overall structure is compact, which is advantageous in terms of installation space, and is also inexpensive in terms of cost.

(4) Because the solenoid valve functions properly and reliably maintains the necessary air cover during natural intake, there is no problem of a reduction in engine output.

[Brief explanation of the drawing]

Figure 1 is a schematic system diagram showing an example of a supercharging system for an internal combustion engine that has a control valve that is directly connected to the accelerator pedal, Figure 2) (b
) (C) and FIG. 3 (XuΦ) (C) are their characteristic diagrams, FIG. 4 is a schematic system diagram showing an embodiment of the supercharging device for an internal combustion engine according to the present invention, and FIG. 5 (Jl) (b), (C), and (d) are characteristic diagrams thereof, and FIG. 6 is a characteristic diagram showing a modified example of the operating characteristics of the TA valve. 1#-・air pump, 2・ee・engine, 3・ψ・
・Clutch mechanism, 4...-Suction side passage, 5@...Air intake port, 6-...-Discharge side passage, 9...EV14 valve, 10#--Accelerator pedal, 11-- ... Throttle valve, 20... Solenoid valve. Patent applicant: Jidosha Kiki Co., Ltd. agent Kazu Yamakawa tfR (one idiot)

Claims (1)

[Claims] The suction side and the discharge side of an air pump that is selectively driven by the engine and forcibly feeds air to the engine intake system are connected via a control valve, and this control valve is connected to the drive system of the throttle valve, and A supercharging device for an internal combustion engine, characterized in that a suction side and a discharge side of the air pump are connected via a solenoid valve.