JPS6126594Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a control device for a supercharger that supplies pressurized air to an engine.

It is known that supplying pressurized air to an engine's intake passage can improve engine output and, in turn, save fuel, and automobile engines equipped with superchargers have recently been widely adopted. .

However, the operating conditions of the engine are constantly changing, and it is not preferable to constantly operate the supercharger in all operating ranges because it may cause a loss of power.

For this reason, conventionally, a supercharging control valve was provided upstream of the intake passage than the throttle valve in the intake passage, and
This supercharging control valve is bypassed to form a supercharging passage, an air pump serving as a supercharger is provided in this supercharging passage, and the supercharging control valve is interlocked with a throttle valve via a link mechanism or the like. west,
A means has been developed in which the supercharging control valve is opened when the throttle valve is in a closed state to release supercharging air to the upstream side of the intake air.

However, the operating conditions in which the engine does not require supercharging are not limited to when the throttle valve is closed, and are not dependent solely on the throttle valve opening; for example, the engine speed, the negative pressure state of the intake manifold, the engine Other conditions such as temperature also have an effect. Therefore, the conventional control means of the supercharging control valve, which is operated via the throttle valve and link mechanism, cannot achieve highly accurate supercharging according to the engine operating conditions. It was impossible to control it.

Furthermore, in order to compensate for air leaks, etc., superchargers generally have an excess supercharging capacity compared to that required by the engine, and such excessive supercharging makes it difficult to control engine operation. There is a problem with this.

The present invention was developed based on these circumstances, and its purpose is to provide a control device for an engine supercharger that can perform supercharging with high precision in accordance with the demands of the engine. .

In other words, the present invention utilizes the pressure difference between the intake upstream side and the intake downstream side of the throttle valve in the intake passage to open and close the supercharging control valve depending on the engine operating conditions, and also to prevent overcharging. When the pressure reaches 100, the supercharging control valve is opened by that pressure, so that necessary and effective supercharging can be performed in all operating ranges.

An embodiment of the present invention will be described below based on the drawings.

In the figure, 1 is the engine cylinder, 2 is the piston,
3 and 4 are intake holes and exhaust holes. The intake hole 3 is opened and closed by an intake valve 5, and the exhaust hole 4 is opened and closed by an exhaust valve 6. The intake hole 3 communicates with a surge tank 7, and the surge tank 7 communicates with an intake passage 8. A throttle valve 9 is provided downstream of the intake passage 8, and the throttle valve 9 is opened and closed by a throttle operator such as an accelerator pedal. The upstream end of the intake passage 8 communicates with an atmosphere opening 11 of the air cleaner 10. Note that 12 is the air cleaner element,
13 indicates an air flow meter.

A supercharging control valve 14 is provided in the intake passage 8 located between the air flow meter 13 and the throttle valve 9. The supercharging control valve 14 is connected to a control lever 16 via a valve shaft 15, and rotates integrally with the rotation of the control lever 16 to open and close the intake passage 8. Note that the operation of the control lever 16 will be described later. A supercharging passage 17 is connected to the intake passage 8, bypassing the supercharging control valve 14. That is, the upstream end of the supercharging passage 17 is connected between the air flow meter 13 of the intake passage 8 and the supercharging control valve 14, and the downstream end is connected between the supercharging control valve 14 and the throttle valve 9. ing.

The supercharging passage 17 is provided with an air pump 18 as a supercharger. This air pump 18 is rotated by an engine crankshaft (not shown). In this case, the air pump 18 (not shown)
The crankshaft and the air pump 18 are connected to each other by a winding transmission means such as a belt hook, and power is switched on and off from the crankshaft to the air pump 18 by an electromagnetic clutch. The electromagnetic clutch is connected and connected based on command signals from the computer 19.
9 is the rotational speed of the engine and the throttle valve 9
The engine operating state necessary to control the air pump 18 is detected, such as the opening degree of the air pump 18, the negative pressure of the surge tank 7, etc., and the engine temperature, and an on/off command signal for the electromagnetic clutch is issued according to each setting condition. It's summery.

The actuator 20 is divided into a first pressure chamber 22 and a second pressure chamber 23 by a first diaphragm 21 . A pressure case 24 is attached to the center of the first diaphragm 21. Therefore, when the diaphragm 21 is bent and deformed due to the pressure difference between the first and second pressure chambers 22 and 23, the pressure case 24 is displaced integrally with the diaphragm 21. Note that the first pressure chamber 22 is provided with a coil spring 25 that constantly presses the diaphragm 21 downward.

The inside of the pressure case 24 is divided into an upper pressure chamber 27 and a lower pressure chamber 28 by a second diaphragm 26 . The upper pressure chamber 27 communicates with the second pressure chamber 23 of the actuator 20 via a communication hole 29 . In addition, a diaphragm 2 is provided in the upper pressure chamber 27.
A stopper 30 is provided to restrict the upward movement of 6. An actuating rod 31 is connected to this second diaphragm 26.
1 is a pressure case 24 and an actuator 20
It is connected to the control lever 16 of the supercharging control valve 14 mentioned above through a loose passage. Therefore, the second diaphragm 26 constitutes the actuating body of the present invention. Note that this second diaphragm 26 may be integrated with the first diaphragm 21. The lower pressure chamber 28 is open to the atmosphere via a bellows 32 installed between the pressure case 24 and the actuator 20.
1 is passed through this bellows 32. A coil spring 33 that pushes up the second diaphragm 26 is housed in the lower pressure chamber 28 .

First pressure chamber 22 in actuator 20
Inside, pressure chambers 37a and 37b separated by partition walls 35 and 36 are formed. These pressure chambers 37a and 27b are provided with check valves 38a and 38b, respectively.
38b, and the check valves 38a and 38b are opened when the pressure inside the first pressure chamber 22 is higher than the pressure in the pressure chambers 37a and 37b. ing. One pressure chamber 37a is communicated with a relief port 40 via a relief passage 39. This relief port 40 is opened between the air flow meter 13 and the supercharging control valve 14 in the intake passage 8 . Further, the other pressure guiding chamber 37b is connected to the first pressure detection port 42 via the first pressure introduction path 41. This first pressure detection port 42 is located downstream of the throttle valve 9 in the intake passage 8 and is open.

In addition, each first pressure chamber 22 of the actuator 20
A second pressure introduction path 43 and a third pressure introduction path 44 are communicated with the second pressure chamber 23, respectively. These second and third pressure introduction passages 4
3 and 44 are connected to a switching valve 45. The switching valve 45 includes pressure receiving chambers 46 and 47, one pressure receiving chamber 46 is connected to the second pressure introducing path 43, and the other pressure receiving chamber 47 is connected to the third pressure introducing path 44. has been done. Both pressure receiving chambers 46 and 47 in the switching valve 45 are connected to the valve hole 48.
are interconnected by. This valve hole 48 is opened and closed by a valve body 49.
The valve body 49 is moved forward and backward by energizing the solenoid 50.

Further, a pressure guiding port 51 is opened in the other pressure receiving chamber 47 so as to face the valve hole 48 . This pressure guiding port 51 is connected to the second
The pressure detection port 53 is electrically connected to the pressure detection port 53. This second pressure detection port 53 is located between the throttle valve 9 and the supercharging control valve 14 in the intake passage 8 and is opened.

The pressure guiding port 51 of the pressure receiving chamber 47 is opened and closed by a valve body 49 that is displaced by the operation of the solenoid 50. In other words, the valve body 49 is designed to close the valve hole 48 and the pressure guiding port 51 when either one is opened. The above solenoid 50
The operation is performed in accordance with instructions from the computer 19 mentioned above. That is, as in the case of controlling the air pump 18 described above, the computer 19 controls the air pump 18 based on the setting conditions according to the operating conditions, such as the engine rotation speed, the opening degree of the throttle valve 9, the negative pressure of the surge tank 7, and the engine temperature. The solenoid 50 is actuated. In this case, the operation of the air pump 18 and the solenoid 5
0 may be activated at the same timing, but each setting condition is set so that the solenoid 50 is activated slightly after the air pump 18 is activated.
The operating conditions of solenoid 8 and the operating conditions of solenoid 50 may be made different.

Note that an orifice 55 is formed in the third pressure introduction path 44 to delay pressure transmission.

The operation of the embodiment configured as described above will be explained.

If the operating conditions of the engine do not meet the conditions set in the computer 19, the electromagnetic clutch of the air pump 18 is released and the air pump 18 is not rotated. Also, in this state, no command signal is given to the solenoid 50, so in the case of the switching valve 45, as shown in FIG. is closed. Therefore, since the second pressure introduction path 43 and the third pressure introduction path 44 are electrically connected through the valve hole 48, the first pressure chamber 22 and the second pressure chamber 23 of the actuator 20 are connected to each other.
and are mutually conductive and maintained at the same pressure. Intake passage 8
The first pressure detection port 42, which is opened to The pressure chamber 22 is made to have the same pressure as the above-mentioned intake negative pressure. Therefore, the first pressure chamber 22 and the second pressure chamber 23 have the same pressure as the large intake negative pressure. Therefore, the first diaphragm 21 is pushed downward by the coil spring 25, so that the pressure case 24 is located in the lower position as shown in FIG. Also, the upper pressure chamber 27 in the pressure case 24
is connected to the second pressure chamber 23, so the second
The diaphragm 26 is located above and abuts against the stopper 30. For this reason, the actuating rod 31 pushes down the control lever 16 of the supercharging control valve 14, so that the supercharging control valve 14
is open.

Therefore, in an operating state where supercharging conditions are not met, the air pump 18 serving as a supercharger remains stopped, and since the supercharging control valve 14 is open, intake air flows through the vicinity of the control valve 14. This is the same situation as an engine without a supercharger.

Next, when each characteristic such as engine speed, throttle opening, surge tank negative pressure, or engine temperature satisfies the supercharging conditions, the computer 19 detects these and connects the electromagnetic clutch of the air pump 18. For this reason, the air pump 18 is driven by the crankshaft and rotates, so it takes in air from the upstream side of the supercharging passage 17 and pumps it downstream, that is, it sends out pressurized air. The computer 19 above
sends a command signal to the electromagnetic clutch, and at the same time,
Alternatively, the signal is also sent to solenoid 50 with a slight delay. Therefore, the solenoid 50 is activated, and the valve body 49 opens the pressure guiding port 51 and closes the valve hole 48, as shown in FIG. As a result, the first pressure chamber 22 of the actuator 20 remains in communication with the first pressure detection port 42, while the second pressure chamber 23 is connected to the third pressure introduction path 4.
4, the pressure guiding port 51 is connected to the second pressure detection port 53 via the fourth pressure introduction path 52. When the second pressure chamber 23 is brought into communication with the second pressure detection port 53 in this way, the pressure of the second pressure detection port 53 gradually decreases based on the flow rate limiting action of the orifice 55. becomes the same pressure.
At this time, pressurized air sent from the air pump 18 is acting on the upstream side of the throttle valve 9, and the pressure on the downstream side of the throttle valve 9 is lower than that on the upstream side. For this reason, the actuator 20
Since the pressure in the second pressure chamber 23 becomes higher than the pressure in the first pressure chamber 22, the coil spring 2
5, the first diaphragm 21 is deflected and the pressure case 24 is moved upward as shown in FIG.

Therefore, based on the upward movement of the pressure case 24, the actuating rod 31 is also pulled up, so that the control lever 1
6, the supercharging control valve 14 is rotated as shown in FIG. 2 to close the intake passage 8.

As a result, since the supercharging control valve 14 is closed when the air pump 18 is rotated, the air pressurized by the air pump 18 does not escape to the upstream side via the supercharging control valve 14 and the throttle valve 9 It is then pumped to the engine. In other words, the engine will be supercharged.

By the way, air pump 18 is generally used as a supercharger.
In order to compensate for air leaks, etc., a pump with a capacity higher than the amount of supercharging required by the engine is used, and excess pressure is generated during supercharging operation as shown in Figure 2. Sometimes. Such surplus pressure is generated as a large positive pressure between the throttle valve 9 in the intake passage 8 and the supercharging control valve 14. This positive pressure acts on the second pressure chamber 23 of the actuator 20 through the second pressure detection port 53.
However, the first diaphragm 21 of the actuator 20 has already been moved up, and the pressure case 24 also remains moved up. However, since the positive pressure in the second pressure chamber 23 also acts on the upper pressure chamber 27 of the pressure case 24 via the communication hole 29,
When the positive pressure in the upper pressure chamber 27 overcomes the coil spring 33, the second diaphragm 26 is moved downward as shown by the imaginary line in FIG. For this reason, the operating lever 31 is pushed down, so the control lever 16
The supercharging control valve 14 is rotated through the intake passage 8.
open. As a result, the supercharging surplus pressure is reduced to the supercharging control valve 1.
4 to the upstream side of the intake air.
Therefore, as the excess boost pressure is released, the pressure upstream of the throttle valve 9 decreases, and this pressure decrease is detected by the second pressure detection port 53 and detected by the second pressure detection port 53.
The supercharging control valve 14 is activated by operating the diaphragm 26 of
to close. In other words, the supercharging control valve 14 is automatically opened and closed according to the pressure upstream of the throttle valve 9, and is operated to keep the supercharging pressure required on the engine side constant, so that the supercharging pressure is high. Accuracy will be maintained.

Note that although the pressure guiding chamber 37b is kept at positive pressure by supercharging, positive pressure is prevented from acting on the first pressure chamber 22 by the check valve 38b. However, even if positive pressure is applied to the first pressure chamber 22 through the check valve 38b and the valve hole 48 due to, for example, a foreign object getting caught, the pressure is applied to the first pressure chamber 22 through the check valve 38a and the pressure chamber 37a. Since the positive pressure in the first pressure chamber 22 is released from the relief passage 39 to the intake passage 8 via the relief port 40, positive pressure in the first pressure chamber 22 is prevented, and the supercharging control valve 14 malfunctions are prevented.

Therefore, according to the above-described embodiment, the supercharging control valve 14 can be controlled with high precision in cases where supercharging is required and cases where supercharging is not required in all operating ranges of the engine. High-performance engine characteristics can be obtained with high accuracy over a long period of time. Furthermore, this embodiment does not use a conventional link mechanism that connects the throttle valve and the supercharging control valve, which prevents the risk of the engine becoming uncontrollable due to a malfunction in the link mechanism. It will also happen.

In addition, in the above embodiment, the pressure chambers 37a,
37b and check valves 38a and 38b, the present invention is not limited thereto. Also, the first pressure chamber 22 of the actuator 20
There are a first pressure introduction path 41 and a second pressure introduction path 4.
Although the two passages in No. 3 are communicated separately, for example, the first pressure introduction passage 41 is connected to connect the first pressure detection port 42 and the pressure chamber 46 in the switching valve 45. Good too.

Further, pistons may be used in place of the first diaphragm 21 and the second diaphragm 26, respectively.

As detailed above, according to the present invention, the first and second
The pressure on the downstream and upstream sides of the throttle valve in the intake passage is introduced into the pressure chamber of the engine, and the pressure difference between these pressures is used to open and close the supercharging control valve. If the setting is made to respond to the conditions that require charging, the necessary supercharging and non-supercharging operations can be selected and set as appropriate, and supercharging can be performed in accordance with the operating conditions of the engine. Moreover, when the fourth pressure introduction path and the third pressure introduction path are connected to each other by the switching valve, one chamber in the pressure case in the actuator introduces supercharging pressure, so excess supercharging pressure In this case, the supercharging control valve can be opened to release excess pressure, thereby making it possible to maintain the necessary supercharging pressure with high precision. Moreover, since the actuator and the switching valve are installed outside the intake passage, there are fewer failures, and even if a failure occurs, repairs can be carried out immediately, so there are advantages such as high safety.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, with FIG. 1 being a schematic diagram of the intake system when not supercharging, and FIG. 2 being a schematic diagram showing the configuration when supercharging. 1... Cylinder, 2... Piston, 8... Intake passage, 9... Throttle valve, 14... Supercharging control valve, 17... Supercharging passage, 18... Air pump (supercharger), 19... Computer, 20... Actuator, 21... First diaphragm, 22...
...First pressure chamber, 23...Second pressure chamber, 24...
...Pressure case, 26...Second diaphragm (operating body), 27...Upper pressure chamber, 28...Lower pressure chamber, 29...Communication hole, 41, 43, 44, 52...
...Pressure introduction path, 42...First pressure detection port,
45...Switching valve, 53...Second pressure detection port.

Claims (1)

[Claims for Utility Model Registration] (1) A supercharging control valve is provided upstream of the throttle valve in the intake passage of the engine, and a supercharging passage is formed by bypassing this supercharging control valve. A supercharger driven by engine operation is provided in the supply passage, and first and second pressure detection ports are opened downstream and upstream of the throttle valve in the intake passage, respectively, and The pressure detection port communicates with the first pressure chamber of the actuator via the first pressure introduction path, and the second pressure detection port is connected to the switching valve via the fourth pressure introduction path, and the switching valve is connected to the switching valve via the fourth pressure introduction path. A valve is connected to a first pressure chamber and a second pressure chamber, respectively, of the actuator through a second pressure introduction path and a third pressure introduction path, and the first and second pressure chambers are in the actuator. A pressure case is provided which is actuated based on the pressure difference between the chambers and is pressed by a coil spring housed in the first pressure chamber, and within this pressure case, the inside of this pressure case is partitioned and the partitioned area is separated. An actuating body operated by the differential pressure between the two chambers is provided, one chamber divided by the actuating body communicates with the second pressure chamber, and the other chamber is open to the atmosphere, The other chamber accommodates a coil spring that presses the actuating body, and this actuating body is connected to the supercharging control valve, and the third pressure introduction path is controlled by the switching valve to control the operating status of the engine. 1. A control device for an engine supercharger, characterized in that the control device is configured to be selectively connected to either the second pressure introduction path or the fourth pressure introduction path depending on the situation. (2) The control device for an engine supercharger according to claim 1, wherein the switching valve is operated by a command signal from a computer based on supercharging setting conditions.