JPH05302520A - Intake device of engine with supercharger - Google Patents

Abstract

PURPOSE:To effectively perform torque control such a traction control by means of a simple structure by effectively utilizing the control valve of a recirculation passage, etc., equipped on a supercharger. CONSTITUTION:A control valve 15 which reacts to a pressure inside an intake passage is provided in a recirculation passage 11 toward a supercharger 4, and a switching means such as a three-way solenoid valve 35 which can be switch a constant pressure introduction condition to a negative pressure introduction condition is provided on a second pressure chamber 24. The control valve 15 leaves a minute space even under a high load at the constant pressure introduction condition, but the control valve 15 is fully opened at the negative pressure introduction condition, and on the other hand, an operational means such as a three-way solenoid valve 47 which openly operates the relief valve 412 of an auxiliary passage 40 which bypasses the control valve 15 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a supercharger in the intake passage and a recirculation passage for recirculating the supercharged air when the engine load is low, and the recirculation passage has a pressure-responsive type. The present invention relates to an intake device for an engine with a supercharger, which is provided with the control valve.

[0002]

2. Description of the Related Art Conventionally, as disclosed in, for example, Japanese Patent Laid-Open No. 2-283816, a mechanical supercharger driven by an engine output shaft is provided in an intake passage, and supercharged air is recirculated at a low load. Intake devices are known which are provided with a passage for controlling the flow and a control valve.

In the intake device shown in this publication, a mechanical supercharger is arranged downstream of the throttle valve in the intake passage, and an intercooler for cooling the supercharged air is arranged further downstream thereof. A recirculation passage (supercharging bypass passage) is provided between the intake passage downstream of the intercooler and the intake passage upstream of the supercharger, and a control valve is provided in this passage. The control valve is driven by a pressure-responsive actuator that guides intake pressure downstream of the throttle valve, is opened when the load is low, and is closed as the engine load increases.

[0004]

By the way, in such an intake system for a supercharged engine, the opening degree of the throttle valve changes in accordance with the accelerator operation and the pressure in the intake passage changes accordingly. The engine torque is adjusted by automatically operating the control valve as described above, but control such as torque down may be required in addition to the torque adjustment corresponding to the accelerator operation.
For example, when the wheels are in a slip state on a low μ road or the like, it is required to reduce the torque to a state in which the slip is appropriately suppressed. Further, it is desirable to regulate the engine torque even when the vehicle equipped with an automatic transmission is running in the reverse range or at the first speed, or when the vehicle speed becomes excessively high. In such a case, in the past, for example, an actuator for electrically driving a throttle valve was provided and controlled, and a separate device for enabling a wide range of torque control was required, resulting in a complicated structure. ..

In view of the above circumstances, the present invention effectively utilizes a control valve or the like in the recirculation passage provided for the supercharger to effectively control the torque down with a simple structure. It is an object of the present invention to provide an intake device for an engine with a supercharger that can be used for other purposes.

[0006]

In order to achieve the above object, a first invention (claim 1) is to provide a supercharger in the intake passage, and to arrange the intake passage at a downstream side and an upstream side of the supercharger. A recirculation passage that communicates with and a control valve that opens in the engine low load side in response to the pressure in the intake passage is provided in the recirculation passage. First and second pressure chambers are formed on both sides of a diaphragm connected to a valve body of the valve, and an intake passage internal pressure that changes according to an engine load is introduced into the first pressure chamber, and the second pressure chamber is also introduced. The chamber is provided with a switching means capable of switching between a constant pressure introduction state and a full-closing operating pressure introduction state different from this, and in the constant pressure introduction state, the control valve leaves a minute gap even when the load is high. Non-fully closed state and the working pressure introduction state for the fully closed state At this time, the operating characteristics of the control valve are set so that the control valve is fully closed at least under high load, while an auxiliary passage bypassing the control valve is provided, and a normally closed auxiliary valve is arranged in this auxiliary passage. The auxiliary valve operating means for opening the auxiliary valve is provided.

A second invention (claim 2) is the above first invention.
In the invention, there is provided control means for controlling the switching means and the auxiliary valve actuating means, the control means is provided with setting means for setting a torque down demand amount in accordance with a slip state of a wheel, and the torque down demand amount is set. Accordingly, one or both of the switching of the control valve from the fully closed state to the non-fully closed state by controlling the switching means and the opening operation of the auxiliary valve by controlling the auxiliary valve operating means are performed. A torque down control means is provided.

A third invention (claim 3) is the above second invention.
In the invention described above, the forced full-open switching means for forcibly switching the control valve to the fully open state is provided, and the forced full-open switching means is operated when the required torque reduction amount is large.

A fourth invention (claim 4) is the above first aspect.
According to the range and the shift stage of the automatic transmission, the control valve is set to the non-fully closed state or the auxiliary valve is opened when the shift stage is the first speed, and the control valve is turned off when the shift range is in the reverse range. Torque regulating means for controlling the switching means and the auxiliary valve actuating means are provided so that the auxiliary valve is opened while being fully closed.

[0010]

According to the structure of the first aspect of the invention, since the control valve has a structure that responds to the pressure in the intake passage, the recirculation amount is normally adjusted automatically in accordance with changes in the engine load. , In addition to this, by the operation of the switching means according to the control signal and the operation of the auxiliary valve operating means,
The recirculation amount can be changed, which allows torque control.

According to the structure of the second aspect of the invention, the structure in which the recirculation amount can be changed is used for traction control, and the torque is adjusted according to the slip state.

According to the structure of the third invention, the range of torque adjustment by changing the recirculation amount can be expanded.

According to the structure of the fourth aspect of the invention, the structure in which the recirculation amount can be changed is utilized for torque limitation during the first speed and the reverse range of the automatic transmission.

[0014]

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an overall structure of an intake device for an engine with a supercharger according to an embodiment of the present invention. In this figure, 1 is an engine body having a plurality of cylinders 2 and 3 is an intake passage for the engine body 1. The intake passage 3 is provided with a supercharger 4 for supplying intake air under pressure. This supercharger 4
Is a mechanical supercharger such as a Risholm type supercharger, and a transmission portion 4a such as a pulley provided at an end of a rotation shaft thereof is connected to an engine output shaft (not shown) via a belt or the like. Is driven by the engine output shaft. Further, the valve timing of the intake valve (not shown) provided in the intake port of each cylinder 2 of the engine is
It is set so that the closing timing is considerably delayed compared to a general engine, which reduces pumping loss at low load and is effective for intake supercharging, intake cooling and intake valve late closing at high load. The filling efficiency is improved.

Upstream of the supercharger 4 in the intake passage 3,
A throttle valve 5 whose opening is adjusted by operating the accelerator pedal or the like is provided, and an air cleaner 6 is arranged on the upstream end side of the intake passage 3. In addition, the intake passage 3
An intercooler 7 for cooling the supercharged air is provided downstream of the supercharger 4 in FIG. A surge tank 8 is formed in the intake passage 3 downstream of the intercooler 7, and a branch intake passage 9 downstream of the surge tank 8 is provided in the engine body 1.
Is connected to the intake port of each cylinder 2.

A recirculation passage 11 that communicates the downstream side and the upstream side of the supercharger 4 with respect to the intake passage 3 is provided, and in this embodiment, the supercharger 4 in the intake passage 3 is provided.
A recirculation passage 11 is formed so as to connect the immediately downstream part and the immediately upstream part of the. The recirculation passage 11 is provided with a control valve 15 that opens at low load to recirculate supercharged air. In addition,
In addition to the recirculation passage 11, an intercooler bypass passage 12 that bypasses the intercooler 7 is provided as shown by a chain double-dashed line in FIG. 1 to prevent supercooling in the non-supercharging region. An on-off valve (not shown) that opens the cooler bypass passage 12 in the non-supercharging region may be provided.

The control valve 15 has a valve body 17 located in a valve body accommodating portion 16 provided in the recirculation passage 11, and a diaphragm 21 connected to the valve body 17 via a rod 22. It is composed of a diaphragm device 20 and is operated according to a pressure change in the intake passage 3. In other words, the valve body accommodating portion 16 has a valve body 17 which has an intake pressure P downstream of the turbocharger from one side (right side in the figure).
_{2 is made} to act, and the pressure P ₁ at the throttle valve downstream is made to act from the opposite side on the upstream side of the supercharger,
In addition, the diaphragm device 20 includes a diaphragm 21
A first pressure chamber 23 provided on one side (left side in the figure) of
The second pressure chamber 24 provided on the other side of the diaphragm 21
And springs 25 and 26 that apply a restoring force to the diaphragm 21 according to its displacement amount.

The first pressure chamber 23 is connected to a passage 31 communicating with the intake passage 3 downstream of the supercharger, and normally the intake pressure P ₂ downstream of the supercharger is introduced into the first pressure chamber 23. It has become so. A three-way solenoid valve 32 as a switching means for forced full opening is interposed in the above-mentioned conduction path 31, and by this three-way solenoid valve 32, the vacuum tank 3 is provided in the first pressure chamber 23.
It is possible to switch from 3 to the state where negative pressure is introduced. The vacuum tank 33 has a check valve 3
4 is connected to an intake passage downstream of the throttle valve or a negative pressure source (not shown) such as a vacuum pump.

Further, the second pressure chamber 24 is provided with a switching means capable of switching between a constant pressure introduction state and a full-closed working pressure introduction state different from the constant pressure introduction state. A two-way solenoid valve 36 is provided in a passage 35 communicating with the two pressure chambers 24. The second pressure chamber 24 is selectively communicated with the intake passage 3 upstream of the throttle valve and the vacuum tank 33 via the three-way solenoid valve 36. The diaphragm 21 and the valve body 17 have the same pressure receiving area.

Further, in order to relieve the supercharging air in the intake passage 3 when the supercharging pressure rises excessively, the valve body 17 of the control valve 15 is bypassed and the recirculation passages 11 on both sides of the valve body 17 are bypassed. Auxiliary passage 40 for connecting relief
And a relief valve (auxiliary valve) 41 that opens and closes the passage 40.
Is provided. This relief valve 41 has a valve body 42.
And a diaphragm 43 connected thereto, and a pressure chamber 44 and a spring 45 located on one side of the diaphragm 43, which are normally closed, and the pressure chamber 44 has a conduction path 46 and a three-way electromagnetic valve as an auxiliary valve operating means. The intake passage 3 upstream of the throttle valve and the vacuum tank 33 can be selectively communicated with each other via the valve 47.

Normally, the pressure in the intake passage 3 upstream of the throttle valve is maintained in a state of being introduced into the pressure chamber 44, and the relief valve 41 is acted upon by the intake pressure P ₂ downstream of the supercharger. The relief valve 41 is opened when the pressure excessively rises above the pressure set by the spring 45 or the like. Even when the boost pressure is excessively increased, the pressure chamber 44 is switched by the switching operation of the three-way solenoid valve 47.
When a negative pressure is introduced into the relief valve 41, the relief valve 41 is forcibly opened.

The three-way solenoid valves 32, 36, 47 are controlled by the control unit 50. The control unit 50 shows a signal from a throttle opening sensor 51 for detecting the opening of the throttle valve 5, a signal from a rotation speed sensor 52 for detecting the engine speed, and slip information for traction control described later. The signal 53 and the like are input. The signal 53 indicating the slip information is, for example, a signal from a sensor that detects the drive wheel speed and the driven wheel speed so that the slip amount of the drive wheel can be checked by the difference between the drive wheel speed and the driven wheel speed of the vehicle. If

FIG. 2 shows the characteristic of the change in the opening of the control valve 15 according to the pressure in the intake passage in the case of the basic control, with the horizontal axis representing the intake pressure P ₂ (boost) downstream of the supercharger. This characteristic is described below.

When the pressure P ₂ downstream of the supercharger acts on the valve element 17 from one side and is introduced into the first pressure chamber 23 of the actuator 20 and also acts on the diaphragm 21, these forces act on each other. Cancel each other out. Further, although the pair of springs 25 and 26 press the diaphragm from both sides, the spring 2 is opened at a small opening position where a minute gap (about 0.5 mm) is left between the valve body 17 and the valve seat.
It is set in advance so that the load by 5, 26 becomes zero. Then, the second pressure chamber 2 of the actuator 20
4, when the pressure P ₀ upstream of the throttle valve is introduced, the pressure P ₁ downstream of the throttle valve acting on the valve body 17 in the closing direction and the throttle pressure acting on the diaphragm 21 in the valve body opening direction. The pressure P ₀ upstream of the valve and the valve body 17
The following relational expression is established from the pressure receiving area S of the diaphragm 21, the opening direction displacement amount x of the valve body 17 based on the position where the load by the springs 25 and 26 becomes zero, and the spring constant k of the spring. To do.

(P ₀ −P ₁ ) S = k · x In this relational expression, since S and k are constant values, the pressure difference between the pressure P ₀ upstream of the throttle valve and the pressure P ₁ downstream of the throttle valve. The valve body 17 is displaced according to (P ₀ −P ₁ ). When the pressure difference becomes equal to or more than a predetermined value, the displacement amount of the valve element 17 is equal to or more than the full opening equivalent amount (the amount in which the opening area between the valve element and the valve seat corresponds to the passage area of other portions). Become,
The control valve 15 is fully opened.

Then, in an operating region up to a predetermined high load, a control state where the above relational expression is satisfied (P in the pressure chambers 23 and 24)
₂ and P ₀ are introduced), the pressure difference (P ₀ −P ₁ ) in the low load region where the throttle opening is small and the boost is low as shown in FIG. Is large, the control valve is fully opened, and as the throttle opening becomes larger (boost rises), the pressure difference becomes smaller, so that the control valve 15 starts from the predetermined pressure Pa at which the boost is lower than the atmospheric pressure. When the valve opening of is gradually reduced, the boost is considerably higher than the atmospheric pressure, and the full load is approached, the control valve 15 is brought into a substantially fully closed state.

However, as long as P ₂ and P ₀ are introduced into the pressure chambers 23 and 24, a minute gap δ is left even in the high load region (two-dot chain line A in FIG. 2). , When the boost reaches a predetermined high load operation state in which the boost exceeds the predetermined pressure Pb, the three-way solenoid valve 36 provided in the communication path 35 leading to the second pressure chamber 24 causes the control unit 50 to operate.
It is operated by the control signal from the above and is switched to a state in which a negative pressure is introduced into the second pressure chamber 24. As a result, when the load is high, the force acting in the valve body closing direction is increased, and the control valve 15 is forcibly brought into the fully closed state (solid line B).

In addition to such basic control, the control unit 50 controls the three-way solenoid valves 32, 3
6 and 47 are changed, the states of the control valve 15 and the relief valve 41 are changed in various ways, which makes it possible to adjust the supercharging recirculation rate. The various states of the control valve 15 and the relief valve 41 obtained by performing the switching control of the solenoid valves 32, 36, 47 are shown.

That is, FIG. 3 shows a state at the time of high load under the basic control, in which the three-way solenoid valve 32 causes the supercharger downstream pressure P ₂ to rise.
When the three-way solenoid valve 36 is installed, the vacuum tank 3
By introducing a negative pressure from No. 3, and by setting the three-way solenoid valve 47 to introduce the throttle valve upstream pressure P ₀ ,
The control valve 15 is fully closed and the relief valve 41 is also closed in principle, and the entire amount of supercharged air discharged from the supercharger 4 is supplied to the engine. From this state, the three-way solenoid valve 36
When the valve is switched to the state in which the throttle valve upstream pressure P ₀ is introduced, as shown in FIG. 4, the control valve 15 changes to a state having a minute gap, and a small amount of supercharging recirculation is performed from the minute gap.

When the three-way solenoid valve 47 is switched from the state of FIG. 3 to the state of introducing the negative pressure from the vacuum tank 33, the control valve 15 is fully closed but the relief valve 41 is opened as shown in FIG. Become. Then, by setting in advance that the relief valve opening amount at this time is larger than the opening amount of the minute gap of the control valve 15, the supercharged air recirculation that is somewhat larger than the state of FIG. 4 is performed. When the three-way solenoid valve 36 is brought into the throttle valve upstream pressure introducing state and the three-way solenoid valve 47 is brought into the negative pressure introducing state, the control valve 15 has a minute gap and the relief valve 41 is opened as shown in FIG. Open and some more supercharging recirculation than in the situation of FIG.

When the three-way solenoid valve 32 is brought into the state of introducing the negative pressure, the negative pressure is introduced into the first pressure chamber 23 so that the control valve 15 is forcibly opened fully as shown in FIG. As a result, the state in which the supercharged air recirculation is maximized is reached.

FIG. 8 shows the axial torque in each state of FIGS. 3 to 7 when the throttle valve is fully opened, where the horizontal axis is the engine speed, and the line Ta is the axial torque in the state of FIG. 3 and the line Tb. Is the shaft torque in the state of FIG. 4, line Tc is the shaft torque in the state of FIG. 5, line Td is the shaft torque in the state of FIG. 6, line Te.
Shows the shaft torque in the state of FIG. 7, respectively. As described above, when the states of the control valve 15 and the relief valve 41 are variously changed, the engine torque changes due to a change in the recirculation amount even with the same throttle opening. Based on the state of FIG. The torque can be reduced from 4 to 4 steps shown in FIG.

Therefore, the engine torque is controlled by the control unit 50 by utilizing such a torque changeable structure, and in this embodiment, the control means composed of the control unit 50 performs the traction control. And a torque down control means 55 for switching the three-way solenoid valves 32, 36, 47 according to the torque down request amount. Has become. The characteristics of the shaft torque in various valve states as shown in FIG. 8 are preliminarily examined using the throttle opening as a parameter, and as a map, the control unit 5 is used.
It is stored in 0, and from this map, the valve state to be controlled can be selected according to the operating state (throttle opening and engine speed) at that time and the required torque reduction amount. ..

Functions of the setting means 54 and the torque down control means 55 are based on a program stored in the control unit 50 in advance.
This is achieved by the control shown in the flowchart of. Explaining the process shown in this flowchart, the control unit 50 first reads signals regarding throttle opening, engine speed, and slip information in step S1, and in step S2, traction control such that the drive wheel slip amount is a predetermined value or more. It is determined whether or not the condition is met.
If not in the traction control condition, in step S3,
The above-mentioned basic control is performed.

If the traction control condition is satisfied, in step S4, the required torque reduction amount is set so that the slip amount can be appropriately suppressed according to the operating state and the slip amount at that time. Then in step S5,
The valve state is determined according to the required torque reduction amount. That is, based on the map of the torque characteristics that has been examined and stored in advance, the valve state in which the torque level is approximately reduced by the required torque reduction amount is examined with reference to the current operating state and valve state.

Then, in step S6, a switching operation signal is output to the three-way solenoid valves 32, 36 and 47 so as to bring the determined valve state.

The operation of the intake system of this embodiment as described above will be described below.

Basically, when the relief valve 41 is closed, the opening of the control valve 15 changes with the characteristics shown in FIG. 2 according to the operating state. As a result, when the throttle valve 5 is closed or the opening is small and the load is low, the control valve 15 of the recirculation passage 11 is fully opened, and an excess portion of the air discharged by the supercharger 4 is discharged. Is recirculated to the upstream side of the supercharger through the recirculation passage 11, the intake amount is adjusted, and the pressure difference between the downstream side and the upstream side of the supercharger is reduced to reduce energy loss in the supercharger 4. To be done. When the boost is increased by gradually opening the throttle valve 5, the opening degree of the control valve 15 is gradually reduced, and the recirculation amount is automatically adjusted. Then, when the boost approaches the predetermined pressure Pb in the supercharging region, it is in a substantially fully closed state, and in the region above the predetermined pressure Pb, the control valve 15 is forcibly fully closed to improve the supercharging performance. Be done.

On the other hand, when the drive wheels slip and the traction control should be performed, steps S4 through S4 in FIG.
By the processing of S6, the torque is reduced by changing the states of the control valve 15 and the relief valve 41 from the basic control state so as to increase the recirculation amount,
Slip is suppressed. In this case, since it is possible to change the torque in multiple stages by combining the change of the state of the control valve 15 and the change of the state of the relief valve 41, it is possible to perform control according to the required torque reduction amount.

In the above device, the three-way solenoid valve 32
3 to 6 even if the forced full-open switching means is omitted.
The torque can be changed in a plurality of steps up to the above by switching the three-way solenoid valves 36 and 47, but if a forced full-open switching means is provided, a wider range of torque control becomes possible.

Further, in the traction control, in addition to multi-stage torque control by changing the states of the control valve 15 and the relief valve 41, air-fuel ratio control, ignition timing control, etc. for fine adjustment of the torque between the respective stages. You may use a torque adjustment means together. Even in such a case, the adjusting means used in combination may be any one capable of finely adjusting the torque within a relatively small range, and it is not necessary to separately provide means for controlling the torque in a wide range.

Further, in addition to or instead of the processing as the setting means 54 and the torque down control means 55 for the traction control, when the automatic transmission is the first speed or the reverse range in the vehicle with the automatic transmission. Alternatively, the control unit 50 may constitute a torque restriction means for restricting the torque. In this case,
As indicated by a chain double-dashed line, a range and gear detection signal 56 from a controller (not shown) of the automatic transmission is input to the control unit 50. Then, based on this signal, the control unit 50 limits the maximum torque to some extent in the first speed as compared with the case in other gears, and further limits the maximum torque in the reverse range to that in the first speed. To control. Specifically, 1
When the speed is high, the control valve 15 is not fully closed or the relief valve 41 is opened, and when the reverse range is set, the control valve 15 is not fully closed and the relief valve 41 is opened.
Control to open.

In this way, it is possible to prevent the torque from increasing more than necessary at the first speed or in the reverse range by utilizing the structure capable of changing the recirculation amount.

In addition to this, the structure in which the recirculation amount can be changed can be used for various torque controls. For example, it determines whether the fuel used is regular gasoline or high-octane gasoline, and in the case of high-octane gasoline, the three-way solenoid valve is controlled according to the normal operating condition, but in the case of regular gasoline, knocking easily occurs in the high load range. Even in the high load range, control may be performed such that the three-way solenoid valve 36 is brought into the throttle valve upstream pressure introducing state and the control valve 15 is not fully closed. Further, in order to regulate the maximum vehicle speed, when the maximum vehicle speed is reached, the three-way solenoid valve 47 may be placed in a negative pressure introduction state and the relief valve 41 may be opened to control the torque. Further, when the temperature downstream of the supercharger or the temperature downstream of the intercooler becomes abnormally high, it is possible to perform control at the time of abnormality such that the relief valve 41 is opened.

[0045]

According to the invention described in claim 1, in the recirculation passage that connects the downstream side and the upstream side of the supercharger,
A control valve is provided which opens in response to the pressure in the intake passage on the low engine load side, and is capable of switching the second pressure chamber between a constant pressure introduction state and a full-closing working pressure introduction state different from the constant pressure introduction state. In the above-mentioned constant pressure introduction state, the control valve leaves a small gap even under a high load, but in the fully-closed operating pressure introduction state, the control valve is fully closed. Since the auxiliary valve actuating means for opening the normally closed auxiliary valve arranged in the auxiliary passage bypassing the control valve is provided, in addition to the automatic operation of the control valve according to the intake pressure, By operating the auxiliary valve operating means, the recirculation amount of supercharged air can be changed in multiple stages. Therefore, by utilizing the control valve and the auxiliary valve for adjusting the recirculation amount, it is possible to control the engine torque in multiple stages with a simple structure.

In the above configuration, as described in claim 2, the control means for controlling the switching means and the auxiliary valve actuating means responds to the required torque reduction amount set in accordance with the slip state of the wheel. When one or both of the switching of the control valve from the fully closed state to the non-fully closed state by controlling the switching means and the opening operation of the auxiliary valve by controlling the auxiliary valve operating means are performed. By using the control valve and the auxiliary valve, it is possible to effectively perform traction control that suppresses wheel slip.

Further, as described in claim 3, a forced full-open switching means for forcibly switching the control valve to the fully open state is provided, and when the torque reduction request amount is large, the forced full-open switching means is provided. When it is operated, the torque control using the control valve and the auxiliary valve can be performed in a wider range.

According to a fourth aspect of the present invention, the switching means and the auxiliary valve actuating means are controlled according to the range and the shift speed of the automatic transmission when the shift speed is the first speed or in the reverse range. When the torque is regulated by using the control valve and the auxiliary valve, it is possible to prevent the torque from being increased more than necessary in the first speed or the reverse range.

[Brief description of drawings]

FIG. 1 is a schematic view of an entire intake device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a valve opening characteristic of a control valve.

FIG. 3 is a diagram showing a first control state of a control valve and a bypass valve.

FIG. 4 is a diagram showing a second control state of a control valve and a bypass valve.

FIG. 5 is a diagram showing a third control state of the control valve and the bypass valve.

FIG. 6 is a diagram showing a fourth control state of a control valve and a bypass valve.

FIG. 7 is a diagram showing a fifth control state of control valves and bypass valves.

FIG. 8 is a diagram showing characteristics of shaft torque in the various control states.

FIG. 9 is a flowchart showing an example of torque control.

[Explanation of reference numerals] 1 engine body 3 intake passage 4 supercharger 5 throttle valve 11 recirculation passage 15 control valve 17 valve body 21 diaphragm 23 first pressure chamber 24 second pressure chamber 32 constituting a switching means for forced full opening Three-way solenoid valve 36 Three-way solenoid valve which constitutes switching means 41 Relief valve 47 Three-way solenoid valve which constitutes auxiliary valve actuating means 50 Control unit as control means 54 Setting means 55 Torque down control means

Claims (4)

[Claims] 1. A supercharger is provided in the intake passage, and a recirculation passage is formed which connects the intake passage with the downstream side and the upstream side of the supercharger. The recirculation passage is provided with a pressure inside the intake passage. Is a supercharged engine provided with a control valve that opens on the low-load side of the engine in response to the first and second sides of a diaphragm connected to the valve body of the control valve.
Pressure chamber is formed, the pressure in the intake passage that changes according to the engine load is introduced into the first pressure chamber, and the second pressure chamber is formed.
The pressure chamber is provided with a switching means capable of switching between a constant pressure introduction state and a full-closing operating pressure introduction state different from this, and in the constant pressure introduction state, a small gap is created even when the control valve is under high load. In the non-fully closed state that remains, and when the working pressure for full closing is introduced, the operating characteristics of the control valve are set so that the control valve is fully closed at least under high load, while the auxiliary passage that bypasses the control valve is set. An intake device for a supercharged engine, characterized in that a normally closed auxiliary valve is provided in the auxiliary passage, and auxiliary valve operating means for opening the auxiliary valve is provided. 2. A control means for controlling the switching means and the auxiliary valve actuating means, wherein the control means sets a torque down request amount according to a slip state of a wheel, and the torque down request amount. According to the above, one or both of the switching of the control valve from the fully closed state to the non-fully closed state by controlling the switching means and the opening operation of the auxiliary valve by controlling the auxiliary valve operating means are performed. An intake system for an engine with a supercharger according to claim 1, further comprising a torque down control means for performing the operation. 3. A forced full-open switching means for forcibly switching the control valve to a fully open state is provided, and the forced full-open switching means is operated when the torque reduction demand is large. The intake device for an engine with a supercharger according to claim 2. 4. The control valve is set to a non-fully closed state or the auxiliary valve is opened when the first speed is selected, or the auxiliary valve is opened when the first speed is selected, and the control valve is set when the speed is in the reverse range according to the range and the speed of the automatic transmission. 2. A torque regulating means for controlling the switching means and the auxiliary valve actuating means is provided so as to open the auxiliary valve while keeping the non-fully closed state.
Air intake device for the supercharged engine described.