JPH073004Y2 - Control device for engine with supercharger - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a control device for a supercharged engine, and more particularly to an EGR (exhaust gas recirculation) control device for a supercharged engine installed in an automobile. Regarding

[Conventional technology]

Conventionally, in the air supply passage communicating with the combustion chamber of the vehicle engine,
It has been proposed to equip the turbocharger with an EGR mechanism that recirculates exhaust gas to the air supply passage.
As the R passage, one that connects the air supply passage upstream of the supercharger and the exhaust passage, and one that connects the air supply passage downstream of the supercharger and the exhaust passage can be considered.

[Problems to be solved by the invention]

However, in the case of such a conventional engine with a supercharger, in the former engine, exhaust gas is introduced into the air supply passage upstream of the supercharger and downstream of the carburetor, so that an engine without a supercharger is provided. Similarly, since the pressure difference between the exhaust pressure and the supply negative pressure is large, it is easy to introduce exhaust gas into the supply passage, but since it enters the exhaust gas supercharger, exhaust deposits adhere to the supercharger. There is a problem that the turbocharger may be damaged.

Further, in the latter, since the exhaust gas is introduced into the air supply passage (inlet manifold) downstream of the supercharger, the differential pressure between the exhaust pressure and the air supply pressure is small, and it is difficult to introduce the exhaust gas into the air supply passage. There is a problem, especially the engine load,
At medium load and above, when the supply pressure becomes larger than the exhaust pressure, the exhaust gas does not flow back to the supply passage, but rather the supply air is supplied (blown through) to the exhaust passage. Exhaust gas (CO, HC) increases, and fuel consumption also deteriorates.

The present invention is intended to solve such a problem, and an object thereof is to provide a control device for an engine with a supercharger, which allows exhaust gas to be recirculated to an air supply passage downstream of the supercharger. And

[Means for solving problems]

Therefore, the control device for the engine with the supercharger of the present invention is
In an engine having a supercharger in the air supply passage, an exhaust gas recirculation passage that can connect the air supply passage downstream of the supercharger and the exhaust passage of the engine, and the exhaust gas recirculation passage An exhaust gas recirculation control valve that is inserted to control the recirculation of exhaust gas to the air supply passage, an exhaust gas recirculation control passage connected to a control unit of the exhaust gas recirculation control valve, and the exhaust gas. A regulating valve for controlling the pressure acting on the control portion of the exhaust gas recirculation control valve so as to set the pressure in the vicinity of the upstream of the gas recirculation control valve to a desired value, thereby making the recirculation rate constant, and the supercharger. A supply pressure detecting passage for receiving a supply pressure of a downstream side supply passage, an exhaust pressure detecting passage for receiving an exhaust pressure from the exhaust passage or the exhaust gas recirculation passage, and a supply pressure from the supply pressure detecting passage The first working chamber introduced by the And a second working chamber for introducing the exhaust pressure from the exhaust gas, and when the supply pressure is larger than the exhaust pressure, the exhaust gas recirculation control passage is opened to the atmosphere and the pressure to the control unit of the exhaust gas recirculation control valve is released. And a differential pressure responsive device for closing the valve and closing the valve.

[Action]

In the control device for the engine with the supercharger of the present invention described above, the differential response device recirculates the exhaust gas so that the EGR is performed until the supply pressure on the downstream side of the supercharger becomes larger than the exhaust pressure. Operate the control valve.

In addition, the regulating valve acts to keep the EGR amount at a constant ratio.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.
1 to 6 show an automobile engine system having a control device for an engine with a supercharger as one embodiment of the present invention. FIG. 1 is an overall configuration diagram thereof, and FIG. 2 is a fuel system thereof. 3 and 4 are graphs for explaining the operation,
4 to 6 (a) are graphs for explaining the operation in the case without the bypass passage, and FIGS. 4 to 6 (b) are all bypasses corresponding to FIGS. 4 to 6 (a). It is a graph for explaining the operation of the one with passages.

As shown in FIG. 1, a combustion system 2 of a vehicle engine 1 is connected to a supply system and an exhaust system, and a supply passage 3 of the supply system is provided with cold air Ac and warm air from an upstream side. Air mix damper 5 for introducing Aw, air cleaner 6,
Inhalation type carburetor with piston (fuel supply mechanism)
7, a throttle valve (supply air amount control mechanism) 8, and a mechanical supercharger that receives a driving force from a clan pulley (not shown) rotationally driven by the engine 1 via a belt (not shown). A supercharger (S / C) 9 is provided.

Further, the air supply passage 3 is composed of an upstream air supply passage 3A which is an upstream portion of the supercharger 9 and a downstream air supply passage 3B which is a downstream portion of the supercharger 9. 3A includes an air supply passage between the carburetor 7 and the throttle valve 8, which is an air supply passage between the cab throttles.
3C and a throttle S / C air supply passage 3D which is an air supply passage portion between the throttle valve 8 and the supercharger 9 are provided.

A muffler 4a is provided near the exhaust port 4b in the exhaust passage 4 of the exhaust system.

Then, the fuel supply mechanism 20 having the carburetor 7 and the throttle valve 8 and the upstream side air supply passage 3A and the downstream side air supply passage 3B of the supercharger (S / C) 9 are cut off from each other to cut off the air supply. And a supercharger bypass mechanism 30 for bypassing the exhaust gas, and the exhaust air from the exhaust system on the downstream side air supply passage 3B.
The EGR mechanism 40 that can be recirculated to the EGR mechanism 40, the EGR control mechanism 50 that controls the EGR state of the EGR mechanism 40, and the air that is controlled by the supply pressure downstream of the S / C and that can supply the supply air from the downstream of the air cleaner 6 to the exhaust passage 4. A cut valve 60 is provided.

The fuel supply mechanism 20 sends the fuel from the fuel tank 70 to the float chamber 75 through the filter 74 by the fuel pump 77. This fuel is supplied from the carburetor 7 to the upstream air supply passage 3C.
In addition to being sent to the fuel supply passage 22 in which the fuel ell cut solenoid (FCS) valve 21 of the carburetor mechanism is inserted, it is sent to the air supply passage 3D on the downstream side of the throttle valve 8 in the vicinity of the throttle valve 8. ing.

In addition, atmospheric pressure is supplied to the fuel increase mechanism through the passage 24.
A throttle positioner 23 as an air supply increasing mechanism for receiving the rod 23b by receiving the rod 23b is provided, and the rod 23b of the throttle positioner 23 is normally protruded by a spring 23c. In contact with each other, the opening of the throttle valve 8 is increased. The passage 24 of the fuel increasing mechanism receives the open operation signal (high negative pressure and high speed) from the OSAC delay valve 25, the engine speed sensor 94 and the switch section 95 which constitute the supply air increasing control mechanism, and is opened. The solenoid valve 26 is inserted.

The supercharger bypass mechanism 30 includes a bypass passage 31 that allows the upstream air supply passage 3A (throttle S / C air supply passage 3D) of the supercharger 9 to communicate with the downstream air supply passage 3B. A bypass relief valve 32 as a bypass valve inserted in the passage 31 and capable of adjusting the communication state of the bypass passage 31, and a valve element 32 formed by the bypass relief valve 32.
and a bypass valve control mechanism 37 capable of controlling the protrusion / retraction of c.

The bypass valve control mechanism 37 is used for the throttle S / C air supply passage 3D.
Solenoid valve 11 and the OSAC delay valve 34 which are connected to the first working chamber (load detecting means) 32a of the bypass relief valve 32 to open the valve body 32c by receiving the negative pressure on the upstream side.
33 (first supercharging pressure reduction control mechanism 38)
And a passage 36 (second supercharging pressure) which is connected to the downstream side air supply passage 3B and receives the positive pressure on the downstream side to open the valve body 32c to the second working chamber 32b of the bypass relief valve 32. Reduction control mechanism 39) and the air cleaner 6
The valve portion 93a with the thermosensor 93 that opens when the downstream temperature is 30 ° C or lower and releases the pressure in the passage 33 to the atmosphere, and the bypass relief valve 32 when the throttle is fully opened and fully closed in a relatively short time. A vacuum valve 27 for preventing residual pressure on the positive pressure side and a passage 28 for sending a large negative pressure from the throttle S / C air supply passage 3D to the working chamber 27a of the vacuum valve 27 are provided.

The solenoid valve 11 is controlled to be opened / closed appropriately by receiving an engine speed signal from the engine speed sensor 94 or a load sensor.

That is, the bypass valve control mechanism 37 prevents the supply air temperature increase mechanism for preventing the supply air temperature from rising when the engine 1 is operating at low load and high speed, and prevents the supercharging pressure when the engine 1 is operating at high speed. It also serves as a supercharging pressure prevention mechanism.

In addition to the above-described configuration, the engine speed and the vehicle speed are detected, and the throttle valve 8 is slightly opened only in the deceleration range where the engine speed or the vehicle speed is equal to or higher than a predetermined value, and the upstream of the supercharger at the time of deceleration is detected. A mechanism may be provided to achieve a reduction in pressure ratio by reducing pressure (close to atmospheric pressure).

Reference numeral 32d represents a spring.

The EGR mechanism 40 includes an EGR passage (exhaust gas recirculation passage) 41, an EGR valve (exhaust gas recirculation control valve) 42 inserted in the EGR passage 41, a working chamber 42a of the EGR valve 42, and cooling water. The communication passage 44 (EGR which connects the thermo valve 43 as a temperature detecting means)
The valve drive negative pressure passage, the exhaust gas recirculation control passage) and the communication passage (exhaust gas recirculation control passage) 45 connecting the working chamber 42a and the cab throttle inter-air supply passage 3C.

Reference numeral 42b represents a spring, and 42c represents a valve body.

Here, the thermo valve 43 is for controlling the operation of the EGR valve 42, is configured as a water temperature valve, and releases the pressure in the passage 44 to the atmosphere at a predetermined temperature or lower to open the working chamber 42a.
It lowers the negative pressure inside and closes the EGR valve 42.
The adjusting valve 46, which will be described later, receives the dynamic pressure of the EGR passage 41 via the passage (exhaust pressure detection passage) 41 ′, opens the passage 46a to the atmosphere, and the EGR rate (the ratio of the EGR amount to the intake amount). Is tuned in that way.

The EGR control mechanism 50 opens / closes the EGR passage 41 by opening / closing the EGR valve 42 as a control target, and connects the vacuum control valve (VCV) 51 to the first working chamber 51a of the vacuum control valve 51. A passage (supply passage detection passage) 80 for supplying supply pressure, a passage (exhaust pressure detection passage) 41 ″ for supplying exhaust pressure to the second working chamber 51b of the vacuum control valve 51, and a third passage of the vacuum control valve 51. A supply passage (EGR valve drive negative pressure passage, which is capable of communicating the supply air pressure of the cab throttle inter-air supply passage 3C to the working chamber (control unit) 51c and communicating with the working chamber 42a of the EGR valve 42,
Exhaust gas recirculation control passage) 45 is provided, and this vacuum control valve 51 compares the supply pressure to the first working chamber 51a with the exhaust pressure of the EGR passage 41 so that the supply pressure is higher than the exhaust pressure. When it is large, push the valve body 51d downwards,
The vacuum control valve 51 is opened and the pressure in the communication passage 45 is released to the atmosphere through the filter 51e.

Further, the EGR control mechanism 50 is provided with a regulating valve 46, and the regulating valve 46 operates to receive the EGR control negative pressure from the communication passage 45 and the control pressure from the control passage 46a. The chamber 46b, the working chamber 46c that receives the exhaust gas from the EGR passage 41 through the communication passage 41 ', the valve body 46d that allows the control passage to communicate with the working chamber 46b in the open state, and the working chamber 46b that is connected to the working chamber 46b. The adjusting valve 46 determines the lift amount of the EGR valve 42, and uses the dynamic pressure of the EGR passage 41 to open the communication passage (EGR valve passage) 45. It is opened to the atmosphere and the EGR rate (ratio of EGR amount to intake amount) is kept constant.

Further, an air cut valve 60 is provided, and the air cut valve 60 receives the S / C downstream supply air pressure via the passage 61 and the air cleaner 6 downstream supply air passage 6.
3 is composed of a working chamber 60c, a working chamber 60d that receives exhaust pressure from the exhaust passage 4 through a passage 62, and a reed valve (check valve) 60a that allows the working chamber 60c and the working chamber 60d to communicate with each other. There is.

The air cut valve 60 burns unburned CO and the like in the exhaust gas by supplying fresh air into the exhaust gas in the valley (negative pressure) of the pulsation of the exhaust pressure.

In the figure, reference numeral 10 is a master back, 29 is an idle-up mechanism, 76 is a passage, 81 is an OSAC delay valve, 83 is a passage, 84 is an orifice, 85 is a solenoid valve, 86 is a filter, and 87 is an air mix damper. Reference numerals 87a and 87b denote working chambers of the vacuum valve 87, and 88 denotes a passage communicating between the working chamber 87b and the valve portion 93a with the thermosensor 93.

Further, on the downstream side of the air cleaner 6, the idle compensator circuit thermo-valve 91 as a supply air temperature detecting means.
And a valve portion 93a with a thermo valve 93 is provided,
When the intake air temperature reaches 80 ° C. or higher, the idle compensator circuit thermo-valve 91 introduces the atmosphere into the upstream air supply passage 3A downstream of the throttle valve 8 via the passage 92,
That is, the carburetor 7 and the throttle valve 8 are bypassed and supplied to make the air-fuel ratio A / F lean.

Further, a communication passage 92 'that connects this passage 92 and the passage 45 of the EGR valve drive negative pressure circuit is provided.

Note that the idle compensator circuit thermovalve 91 may not be provided with the communication passage 92 ', but a thermovalve dedicated to the communication passage 92' may be provided. Lower than the compensator circuit thermo-valve 91.

Further, reference numeral 94 denotes an engine circuit number sensor, 95 denotes a switch portion which is opened when a negative pressure from the passage 33 is received in the working chamber 35a of the vacuum valve 35 which constitutes the rapid deceleration detection mechanism, and 96 Is a negative pressure advancement device for a distributor connected to the vacuum valve 82, 97 is an ignition switch, and 98 is a vehicle speed corresponding control unit (Vmax signal relay for controlling the carburetor 7 to project at a vehicle speed higher than a set value to reduce the vehicle speed. ), 99 is throttle position sensor, 100
Indicates a communication passage opening, and B indicates a battery.

The symbols shown in Fig. 1 * 1, between * 2, and * 3
They are connected to each other, and the reference numeral 78 in FIG.
VST, 79 is a fuel return valve.

Also, a mechanism for prohibiting EGR may be provided in conjunction with idle up.

As the air supply amount control mechanism, a mechanism may be used in which a bypass passage that bypasses the throttle valve 8 is provided and the opening / closing of the valve inserted in the bypass passage is controlled.

Since the control device for the engine with the supercharger as the embodiment of the present invention is constructed as described above, the main control performed for the engine 1 will be described below.

Fuel control (1-1) Normal time (1-2) Fuel increase in specific operation area Supercharging pressure control (2-1) High speed small throttle opening (2-2) High speed (supercharging pressure prevention (2-3) Other EGR control (3-1) When supercharging pressure is higher than exhaust pressure (3-2) When cooling water temperature is low (3-3) When intake air temperature is high Fuel control (1-1 ) Normal time As the fuel control in the present embodiment, one that determines the amount of fuel supplied from the carburetor 7 to the intake passage 3 by controlling the opening degree of the throttle valve 8 by a cable connected to an accelerator pedal is used. The fuel supplied to the intake passage 3 is sent to the downstream side air supply passage 3B through the supercharger 9 and is vaporized in the downstream side air supply passage 3B to remove latent heat of vaporization and to the downstream side of the supercharger 9. Has the function of cooling the high-pressure air-fuel mixture.

As a result, the temperature of the air-fuel mixture in the downstream air supply passage 3B is raised by the supercharger 9 while the temperature is lowered, so that the charging efficiency is increased and the engine output is increased.

(1-2) Fuel Increase in Specific Operating Region Further, in the fuel control, fuel amount increasing control is performed. This fuel amount increasing control is performed in a specific operating region of the engine 1 [Z in FIG. 3]. Reference], the throttle valve 8 is driven in the opening direction by the throttle positioner 23 to increase the throttle opening degree from the current opening degree.

That is, when the engine speed signal and the negative pressure signal from the engine speed sensor 94 are received, and when the engine speed is high and the negative pressure is low, the solenoid valve 26 is opened, the passage 24 is opened to the atmosphere, and the atmospheric pressure is reduced. Throttle positioner 23 working chamber 23
It is supplied to a, the rod 23b is projected, and the throttle member that abuts on the rod 23b is rotated to increase the opening degree of the throttle valve 8.

When the solenoid valve 26 is not operated, the throttle opening becomes small, and when the throttle valve 8 comes to the left of the port 100, the throttle valve S
The spring 23c of the working chamber 23a is compressed by the negative pressure of the / C air supply passage 3D, and the rod 23b does not project.

Supercharging Pressure Control (2-1) At High Rotation Small Throttle Opening As the supercharging pressure control in this embodiment, the bypass passage 31
In order to reduce the pressure of the downstream side air supply passage 3B and recirculate the supercharged air to the upstream air supply passage 3A by controlling the communication state of the recirculation in the state where the engine speed is high and the throttle opening is small There is a first supercharging pressure reduction control to be performed and a second supercharging pressure reduction control to recirculate in a state where the engine speed is high and the throttle opening is large. In addition, the negative pressure generated upstream of the supercharger is received by the first supercharging pressure reduction control mechanism 38, and the bypass relief valve 32 is opened to supercharge from the downstream side air supply passage 3B to the upstream side air supply passage 3A. Return the air,
By decreasing the supercharging pressure and decreasing the ratio of the upstream pressure and the downstream pressure, the discharge side mixture gas temperature becomes lower than that of the non-bypass (recirculation) type shown in FIG. See FIG. 6 (b)].

(2-2) During high rotation (prevention of supercharging pressure) In addition, the second supercharging pressure reduction control is performed when the engine is overrotating at the time of full opening, and when friction is reduced when the engine is sufficiently slid. Then, the second supercharging passage reduction control mechanism 39 receives a supercharging pressure (supercharging pressure) equal to or higher than a predetermined value to open the bypass relief valve 32, and the downstream side supply passage 3B.
From the upstream side air supply passage 3A to the upstream side air supply passage 3A, and the supercharging pressure becomes lower than that without bypass (recirculation) shown in FIG. 4 (a) [see FIG. 4 (b)]. Prevent pressure supply.

In addition, FIG. 5 (a) shows a cab S / that does not bypass (recirculate).
5 shows the temperature of the air-fuel mixture in the C-air supply passage, and FIG. 5 (b) shows the temperature of the air-fuel mixture in the cab S / C air-supply passage 3C when bypassed (recirculated).

(2-3) Others When decompressing the supercharging pressure, there is a possibility that a sudden deceleration will occur from the full open range. Therefore, the vacuum solenoid valve 27 is activated, the pressure in the passage 36 is released to the atmosphere, and the second operation is performed. Room
Release the pressure in 32b to the atmosphere so that the function to prevent temperature rise during deceleration is not hindered.

By combining the first supercharging pressure decrease control and the fuel increase control in the fuel control, the temperature lowering effect can be further enhanced.

EGR control (3-1) When the supercharging pressure is higher than the exhaust pressure The EGR valve 42 in the EGR control mechanism 40 is driven by the negative pressure in the vicinity of the cab-throttle air supply passage 3C sent through the passage 45, and is adjusted. The valve 46 controls the opening and closing of the valve to control the EGR rate.

In the EGR valve drive negative pressure take-out section, the EGR valve 42 is opened even in the high load area due to the constant negative pressure, and the downstream side supply pressure (inlet manifold positive pressure) and the exhaust side positive pressure are set in the vacuum control valve 50. When the fresh air has a pressure to blow through to the exhaust side, the passage (EGR valve drive negative pressure circuit) 45 is opened to the atmosphere and the EGR valve 42 is closed to prevent blow-through. Also, exhaust pulsation can be reduced.

(3-2) When the cooling water temperature is low When the thermo valve 43 as the cooling water temperature detecting means detects that the engine is not warming up (55 ° C or lower), the thermo valve 43 is opened. The passage 44 of the EGR valve drive negative pressure circuit is opened to the atmosphere, the EGR valve 42 is closed to stop (prohibit) the EGR, and it is possible to prevent a reduction in feeling and a reduction in power performance.

(3-3) When the intake air temperature is high Furthermore, the intake valve cooling state (80
Temperature) is detected, the idle compensator circuit thermo-valve 91 is opened, the EGR valve drive negative pressure circuit passage 45 is opened to the atmosphere, the EGR valve 42 is closed, and the EGR valve is closed. It can be stopped (prohibited), the feeling can be prevented from decreasing, and the power performance can be prevented from decreasing.

In addition, when the cooling water temperature is higher than 55 ° C and the intake air temperature is lower than 80 ° C, the EGR distribution during idle-up is less frequent. Therefore, there is an advantage that the carburetor does not need to be changed between the vehicle equipped with the cooler and the vehicle not equipped with the cooler, and the frequency of idle instability is reduced.

Further, cost reduction can be achieved by promoting sharing of parts and simplification of parts.

In the idle-up mechanism, when the load component (cooler or the like) of the engine 1 is detected to be in an operating state or an operating preparation state, the EGR is prohibited in combination with a cooling water temperature detecting means or an intake air temperature detecting means as appropriate. Good.

Furthermore, the thermo valve 91 for the idle compensator circuit
If a thermo valve, which is separate from the above, is newly provided close to the thermo valve for controlling the idle compensator, the carburetor can be shared with that of the vehicle without the cooler, and the idle unstable region can be eliminated.

[Effect of device]

As described above in detail, according to the control device for an engine with a supercharger of the present invention, in the engine having the supercharger in the air supply passage, the air supply passage downstream of the supercharger and the engine An exhaust gas recirculation passage capable of communicating with the exhaust passage of the exhaust gas, an exhaust gas recirculation control valve inserted in the exhaust gas recirculation passage and capable of controlling recirculation of exhaust gas to the supply passage, An exhaust gas recirculation control passage connected to a control unit of the exhaust gas recirculation control valve, and a control unit of the exhaust gas recirculation control valve so as to set a pressure near the upstream side of the exhaust gas recirculation control valve to a desired value. From the regulating valve for controlling the acting pressure to keep the recirculation rate constant, the air pressure detection passage for receiving the air pressure of the supercharger downstream air supply passage, and the exhaust passage or the exhaust gas recirculation passage. Exhaust pressure detection passage that receives the exhaust pressure of When the supply pressure is higher than the exhaust pressure, the exhaust gas includes a first working chamber for introducing the supply pressure from the detection passage and a second working chamber for introducing the exhaust pressure from the exhaust pressure detection passage. It has a simple structure in which the recirculation control passage is opened to the atmosphere, the pressure supply to the control part of the exhaust gas recirculation control valve is stopped, and the valve is closed. It is possible to obtain various effects or advantages.

(1) The exhaust gas recirculation control mechanism allows the EGR gas to be introduced into the downstream air supply passage of the supercharger.

(2) By introducing EGR gas downstream of the supercharger,
Since the exhaust deposit is not introduced into the supercharger, damage to the supercharger due to the exhaust deposit can be prevented, and further, deterioration of the seal of the supercharger and lubricating oil due to high temperature exhaust gas is small.

(3) by operating the exhaust gas recirculation control valve differential pressure responsive device, EGR can be performed until the last minute that the boost pressure of the supercharger downstream side becomes larger than the exhaust pressure, NO _x reduction by EGR action Is sufficiently obtained.

(4) By operating the exhaust gas recirculation control valve with the differential pressure response device, it is possible to prevent intake air from blowing through to the exhaust passage, thereby preventing deterioration of exhaust gas (CO, HC) and fuel consumption. it can.

(5) The EGR amount can be maintained at a constant ratio by the adjusting valve.

[Brief description of drawings]

1 to 6 show an automobile engine system having a control device for an engine with a supercharger as one embodiment of the present invention. FIG. 1 is an overall configuration diagram thereof, and FIG. 2 is a fuel system thereof. 3 and 4 are graphs for explaining the operation,
4 to 6 (a) are graphs for explaining the operation in the case without the bypass passage, and FIGS. 4 to 6 (b) are all bypasses corresponding to FIGS. 4 to 6 (a). It is a graph for demonstrating the effect | action in the thing with a road. 1 ... Vehicle engine, 2 ... Combustion chamber, 3 ... Air supply passage, 3A ... Upstream air supply passage, 3B ... Downstream air supply passage, 3C
...... Cab throttle air supply passage, 3D ...... Throttle S /
Air supply passage between C, 4 ... Exhaust passage, 4a ... Muffler, 4b ...
… Exhaust port, 5 …… Air mix damper, 6 …… Air cleaner, 7 …… Carburettor, 8 …… Throttle valve, 9 ……
Supercharger (S / C) as a mechanical supercharger, 10 ...
… Master back, 11… Solenoid valve, 20… Fuel supply mechanism,
21 …… Fuel cut solenoid (FCS) valve, 22…
… Fuel supply path, 23 …… Throttle positioner (supply increase mechanism), 23a …… Working chamber, 23b …… Rod, 23c …… Spring, 24 …… Passage, 25 …… OSAC delay valve, 26…
… Solenoid valve, 27 …… Vacuum valve, 27a …… Working chamber, 2
8 …… passage, 29 …… idle up mechanism, 30 …… supercharger bypass mechanism, 31 …… bypass passage, 32…
... Bypass relief valve (bypass valve), 32a ... first working chamber, 32b ... second working chamber, 32c ... valve element, 32d
...... Spring, 33 ...... passage, 34 …… OSAC delay valve, 35 …… vacuum valve, 36 …… orifice, 37…
… Bypass valve control mechanism, 38 …… First boost pressure reduction control mechanism, 39 …… Second boost pressure reduction control mechanism, 40 …… EGR mechanism (exhaust gas recirculation mechanism), 41 …… EGR passage (Exhaust gas recirculation passage), 41 '... passage (exhaust pressure detection passage), 42 ...
… EGR valve (exhaust gas recirculation control valve), 42a …… Working chamber, 42
b …… spring, 42c …… valve element, 43 …… thermo valve (water temperature valve), 44 …… communicating passage, 45 …… communicating passage (exhaust gas recirculation control passage), 46 …… regulating valve, 46a …… Control passage, 46b, 46c ... Working chamber, 46d ... Valve body, 46e ... Filter, 50 ... EGR valve control mechanism (exhaust gas recirculation control mechanism), 51 ... Vacuum control valve as differential pressure response mechanism (VCV), 51a ... first working chamber, 51b ... second working chamber, 51c ... third working chamber (control section), 51d ...
Valve body, 51e …… Filter, 60 …… Air cut valve, 60a
...... Reed valves, 60b, 60c, 60d …… Working chambers, 61-63…
… Passage, 69… Thermo valve, 70… Fuel tank, 71…
… Canister, 72 …… Outer vent valve, 73 …… Fuel supply passage, 74 …… Filter, 75 …… Float chamber, 76 …… Passage, 77 …… Pump, 78 …… VST, 79 …… Fuel return valve, 80 …… passage (passage for air pressure detection), 81 …… OS
AC delay valve, 82 …… vacuum valve, 83 …… passage, 84 …… orifice, 85 …… solenoid valve, 86 …… filter, 87 …… vacuum valve for air mix damper, 87
a, 87b …… Operating chamber, 88 …… passage, 91 …… Idle compensator circuit thermo valve, 92 …… passage, 92 ′ …… communicating passage, 93 …… thermosensor, 93a …… valve section, 94 …… Engine speed sensor (engine speed detection means) that constitutes the supply air amount increase control mechanism, 95 ... switch section, 96 ... negative pressure advance device for distributor, 97 ... ignition switch, 98 ... control section for vehicle speed (Vmax signal relay),
99: Throttle position sensor, 100: Opening for communication passage, B: Battery.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Koichi Nakanishi, No. 1 Uzumasa-cho, Ukyo-ku, Kyoto City, Kyoto Prefecture Mitsubishi Motors Corporation Kyoto Works (56) References: 60-159870 (JP, U) Public Sho 58-25865 (JP, B2)

Claims (1)

[Scope of utility model registration request] 1. An engine having a supercharger as an air supply passage, and an exhaust gas recirculation passage capable of communicating an air supply passage downstream of the supercharger with an exhaust passage of the engine.
An exhaust gas recirculation control valve that is inserted into the exhaust gas recirculation passage and can control recirculation of exhaust gas to the air supply passage;
An exhaust gas recirculation control passage connected to the control unit of the exhaust gas recirculation control valve, and a control unit for the exhaust gas recirculation control valve so as to set a pressure near the upstream side of the exhaust gas recirculation control valve to a desired value. A regulating valve for controlling the pressure acting on the recirculation rate to keep the recirculation rate constant, a supply pressure detection passage for receiving the supply pressure of the supercharger downstream side supply passage, the exhaust passage or the exhaust gas recirculation passage An exhaust pressure detecting passage for receiving the exhaust pressure from the first exhaust gas, and a first introducing the supply pressure from the supply pressure detecting passage
Of the exhaust gas and the second working chamber for introducing the exhaust pressure from the exhaust pressure detecting passage, the exhaust gas recirculation control passage is opened to the atmosphere to release the exhaust gas when the supply pressure is larger than the exhaust pressure. A control device for an engine with a supercharger, comprising: a differential pressure responsive device that stops supply of pressure to the control unit of the recirculation control valve and closes the valve.