JPS6075733A - Supercharge controller for internal-combustion engine - Google Patents

Abstract

PURPOSE:To improve the acceleration response from low load area by setting the referential supercharge pressure in step on the basis of engine rotation and accelerator opening while increasing said referential supercharge pressure in accordance to the stepping speed of accelerator. CONSTITUTION:A supercharge pressure setting circuit 40 comprised of CPU is provided with output signals from an engine rotation detecting means 41 and an accelerator opening sensor 42 to retrieve a control map in accordance to both signals thus to decide whether is is full-supercharge, semi-supercharge or no- supercharge. Here, the referential supercharge pressure is set in step such that it will be specific supercharge in semi-supercharge area. While in accordance to the magnitude of accelerator stepping speed detected by an accelerator stepping speed detector 60, the referential supercharge pressure is increased in step. The opening of waste gate valve 24 detouring the turbine of supercharge is feedback controlled on the basis of a referential supercharge signal produced from a setting circuit 40 to control the supercharge pressure of supercharger 21.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a device for controlling the intake chamber speed of a supercharged internal combustion engine according to operating conditions.

1 to improve acceleration response especially from medium speed and low load range.
5.Regarding a supercharging control device.

[Technical background]

In internal combustion engines equipped with a supercharger such as a turbocharger for the purpose of improving fuel efficiency and increasing output, the supercharging action of the supercharger is controlled according to the engine rotation conditions, but the supercharging control device For example, Nirakei Mechanical 1983 5F
An example is disclosed in JQ E1, pages 135-144, and there is a control force formula as shown in FIG. 4, shown on page 140 of the same magazine.

However, with this control method, the boost pressure is simply controlled according to a single setting curve that increases in response to an increase in engine speed, and the In the case where full supercharging is required even at the ρ1 rotation number, there is a drawback that it is not possible to sufficiently control and supply an appropriate supercharging pressure to the engine.

On the other hand, the applicant has proposed a supercharging a that eliminates the defects described in I-1.
An application has already been filed for a control system for the
52,920 inches). This system 11 uses 'JA SQ as shown in FIG. 1 as a base. Intake air introduced from an air cleaner 1 passes through a carburetor 2 to generate an air-fuel mixture having a predetermined air-fuel ratio, and this air-fuel mixture is sent to an intake compressor (supercharger) 4 which is driven by the engine via a route 3. The fuel is supercharged by the engine, and is guided to each cylinder of the engine body 5 at a predetermined supercharging pressure.

Bypass intake passage 6 that bypasses the intake compressor 4
is provided with a control valve 7 that controls the supercharging action according to conditions outside the operating system. When the boost pressure exceeds a predetermined value,
A relief valve 8 for returning supercharging air to the li flow of the intake compressor 4 is provided in parallel with the control valve 7. Reference numeral 9 denotes an electromagnetic clutch that connects and disconnects the drive of the intake compressor 4.

iI! The setting of lS supply pressure is as shown in Fig. 2.
In this city, it is determined by engine speed and accelerator opening.
In the figure, Δ is the full supercharging region, B is the half supercharging region, and C is the non-supercharging region. As is clear from the figure, in general, as the accelerator opening (engine load) increases, the supercharging effect is set to work more strongly, and within the semi-supercharging region, the The supercharging section (or pressure) can be controlled.

This type of supercharging control device still has the following drawbacks. That is, in the medium speed and low load operating range (for example,
If you just press the accelerator slightly from the point (for example,
’ point), the supercharging effect does not work, and in this case, the supercharging effect is reduced to 11
7, the accelerator must be depressed considerably, making it impossible to obtain sufficient acceleration response, especially when driving downhill or when reaccelerating immediately after engine braking.

[Purpose of the invention]

An object of the present invention is to provide a supercharging control device of the type described above.
In addition, the supercharging action is activated appropriately in response to the four rolling points 1,
It is an object of the present invention to provide a control system that improves acceleration response, particularly from a low load range, regardless of engine speed.

[Structure and operation of the invention]

To this end, the present invention basically consists of a supercharger provided in the intake passage, a means for detecting the engine speed, a stage for detecting the accelerator opening, and a stage for detecting the accelerator opening, as shown in FIG. The reference supercharging pressure is set in stages based on the detected engine rotation speed and the detected accelerator opening.Supercharging is controlled based on the output of the semi-supercharging pressure setting circuit and the reference supercharging pressure setting circuit. In addition to these supercharging devices, there is also a means for detecting the accelerator depression speed, and a supercharging pressure correction circuit that increases the reference supercharging pressure for a predetermined period each time the detected accelerator depression speed increases. Equipped with.

According to this configuration, under normal conditions, the supercharger is basically controlled so that the supercharging pressure (standard supercharging pressure) corresponds to the rotation speed and accelerator opening, but at medium speeds When the accelerator is pressed hard (rapidly) in the low load range, etc., the reference boost pressure is set high for a predetermined period of time depending on the direction of the boost pressure correction circuit, thereby improving the response during acceleration. .

〔Example〕

Hereinafter, embodiments of the present invention will be described based on the drawings. FIG. 4 is a schematic block diagram of an embodiment of the present invention, and FIG. 5 is a circuit diagram of the system J.

The intake passage downstream of the air cleaner l is equipped with an intake compressor 21 as a supercharger that rotates coaxially with the driving force of the exhaust turbine 20, and an air loss passage 22 is provided with an air loss bypass that bypasses the air loss turbine 20. A passage 23 is provided, and a wastegate valve 24 as a means for controlling the flow rate of supercharging air is interposed in this passage 23.

This wastegate valve 24 is driven by a guyaphram device 25 that operates according to the boost pressure, and when the boost pressure reaches a predetermined value or higher, the diaphragm 26 pushes out the rod 28 against the spring 27 and the valve body 29 open. The wastegate valve 24 also opens or closes depending on the rotational direction of the electric motor 30, as shown in FIG.

That is, the shaft 31 of the electric motor 30 has a threaded portion 3.
2 is formed, and a slide plate 33 that engages with this threaded portion 32 moves left and right in the figure in response to the shaft 31, thereby rotating the lever 34 in a predetermined direction and setting the wastegate valve 24 to a predetermined opening degree. do. In this embodiment, the slide valve L・71-33 (from position 5 to r') is detected by the both/geometer 35, and based on this detected opening degree signal a, the wastegate valve is adjusted as described later. Opening 1■ is feedback controlled.

The CPU 40 as a boost pressure setting circuit receives a rotation speed signal N from a crank sensor 41 as an engine rotation speed detection means.
e. An accelerator opening signal 0 is input to the accelerator opening sensor 42 as a means for detecting the accelerator opening. C.P.
In U40, based on these confidences 1; Ne, 0, ttS
Look up the control map in Figure 2 and set the supercharging areas A, B,
Corresponding to C, full supercharging, half supercharging, no supercharging II! One of the S ships is determined, and this supercharging signal is output as a three-stage analog voltage signal to the nail clipper motor drive circuit 43. At this time, in the half-supercharging region B, the optimum supercharging pressure is set in stages so as to reach a predetermined supercharging pressure according to the coordinate PiJ.

The electric motor drive circuit 43 converts this supercharging signal and the detected waste I gate valve open 1a 4E into a comparator 44.
For example, the detected waistgear 1-jr opening signal a
If the voltage value of the supercharging signal is higher than the voltage value of the supercharging signal, the L lever is applied to the comparator 441 and the comparators 45 to 47, respectively.
Outputs a signal. At this time, the comparator 45.47
is the relationship between the L level input signal to the non-inverting terminal and the reference voltage '?
Compare f (o position) and (output a level signal, so switch the swifting I/tensisters 50 and 51 to O).
Set it to N. Also, the comparator 46 outputs 1 lbel to the comparators 48 and 49, and this (V) and (?
Comparators 48 and 49 to which the lli voltage signal is input each output an L level signal, turning off switching transistors 52 and 53, respectively.

As a result, transistors 50 and 51 become conductive and transistors 52 and 53 are cut off, so that the power supply VD
A predetermined drive current flows from D in the direction of the arrow in the figure, causing the electric motor 30 to rotate 11 times.

Therefore, the slide plate 33 is moved to the right in the figure by the drive of the motor 30, and the displacement of the exhaust gas is reduced via the lever 34, thereby increasing the supercharging pressure.

Conversely, if the detected wastegate I/valve opening signal Sj a from the potentiometer is a higher voltage signal than the supercharging signal S from the CPU 40, the comparator 44 outputs a 1 level signal to the comparators 45 to 47. Since only the transistors 52 and 53 become conductive via the comparators 47 and 48, the drive current flows in the opposite direction of arrow B, causing the electric motor 30 to reverse. As a result, the waste gate valve 24 expands to a predetermined opening degree, increases the haypass exhaust 11i, and lowers the supercharging pressure.

In this way, basically, the CPU 40 outputs a predetermined reference supercharging signal 5b to the electric motor drive circuit 43 in response to the engine rotation speed times -) Ne accelerator opening signal 0, and this reference supercharging signal 5b is output to the electric motor drive circuit 43. The electric motor 30 is rotated in a predetermined direction based on the signal, and the J1 opening degree of the waste gate J24 is set to a predetermined supercharging pressure.

The accelerator depression movement speed detecting means, which is a characteristic part of the present invention, is composed of a circuit 60 shown in FIG. , an IIL river proportional to the depression angle (accelerator opening) 0 is output from the potentiometer 63 to the 1f1 dynamic contact 64.

Junction point 67 of voltage dividing resistors 65 and 66 and potentiometer 6
A capacitor 68 is connected between 3 and 3, and a differential circuit is formed by this capacitor 68 and resistor 66, and when the accelerator is depressed, a voltage V proportional to the temporal change rate of the depression angle 0 (accelerator depression speed) 3<4 is generated. is the junction point 67
occurs in

J of t ml co/parator 70 and second comparator 71
1 inverting input terminal is applied with the proportional voltage shown below, and the other inverting input terminal is applied with resistors 72, 73, 74, and 7.
'1 pressure Vl, V2 divided by 5 (however, Vl >
V2) are applied respectively. And, for example, V
If l>V2≧V, each comparator 70, 71 outputs a II level signal to the CPU 40. Vl≧V>V2
If so, the first comparator 70 outputs L-level signals, and the second comparator 71 outputs L-level signals, and if V>Vl>V2-Ill', both comparators 7
0°71 both output L level signals to the CPU 40.

CPU 40 i, t, , 1ili j 7 palators 70, 71 In response to the color signal, Ti1j is the group described above? #
Increase and correct the boost pressure in stages. In other words, the CPU 40 as a boost pressure correction circuit calculates the reference boost pressure based on the rotation speed signal Ne and the accelerator opening signal θ, and in response, a predetermined accelerator depression speed signal is sent from the circuit 60. When inputting as a jump faith, base 11
(Comparer 1/
- Corrected supercharging pressure C,j to be output on 44th! , >C
If the output signal of the first comparator 70 is at L level and the output signal of the second comparator 71 is at L level, then
Fully supercharged 5) (high voltage signal) If the output signal of the first comparator 70 is L level and the output signal of the second comparator 71 is L level, the half supercharged signal (medium voltage @''; +
), and the output signal of the first comparator 70 becomes L.
If the output signal of the second comparator 71 is at L level, it becomes a non-supercharging signal (low voltage signal).

1. Therefore, for example, when stepping on the accelerator rapidly from a medium speed and low load range, the total supercharging signal C is used as the corrected supercharging pressure signal.
is output to the comparator 44 with priority over the reference boost pressure signal, and when the accelerator opening is held constant in the medium speed and medium load range, the no-supercharging signal C as the corrected supercharging fE times signal is The reference supercharging positiveity V) b is output to the comparator 44 as it is. Repair 1 [Supercharging pressure signal C is CPU
4. When output from O to the comparator 44, the CPU
After a certain period of time has elapsed using a timer installed in the engine 40, the supercharging pressure signal C is cut and supercharging is controlled based on the normal (normal) A semi-supercharging pressure signal.

An example of the operation of the CPU 40 will be explained based on flowchart 1 in FIG.・Turn on f-ma. When the timer measures a predetermined time (51 seconds), the timer is turned OFF, the corrected supercharging pressure signal C is sent), and the predetermined opening If ( Px). However, if the accelerator depression speed falls below a predetermined negative value -q while the timer is measuring t seconds, the boost pressure correction will be canceled immediately. , set the wastegate valve as usual. Even when the accelerator depression speed is smaller than the predetermined value 4F1)2, the supercharging control I roll is performed according to the control map.

In addition, - in the above-mentioned embodiment, the case where a turbocharger was used as a supercharger was explained, but the supercharger of the present invention may be an engine-driven one (for example, a positive displacement supercharger such as a Roots blower type, or A variable volume co/breather '5) may also be used. In addition, as a means to control the supercharging air flow 1,
It may be configured by installing a control valve 7 in the bypass intake passage 6 to bypass the IA charger 4 as shown in FIG. A sub-intake passage LOa may be provided which communicates with the sub-intake passage 10a, and the control valve 7 may be interposed in this sub-intake passage 10a.

FIG. 8 shows an example of the relationship between boost pressure and engine speed Ne according to an embodiment of the present invention.

2 (The control by semi-supercharging Seishigin is performed as follows.

In FIG. 2, the semi-supercharging region, ie, the intermediate region (B), is made up of subdivided cells, and the region (C) side supplies a relatively small amount of supercharging pressure, and the region (A ) side, a boost pressure close to the maximum boost pressure is supplied to prevent the hunting phenomenon. In the intermediate region (B), when the accelerator opening signal increases, a wide line corresponds to the engine rotation speed, and when the rotation speed decreases, a wide line corresponds to the acceleration request signal.
It is defined by the area connecting these lines. The depression l in such a relatively wide intermediate region has a +f effect in creating a supercharging state corresponding to the running line f1 of the center shaft. In other words, when the accelerator opening signal decreases or the rotational speed increases, a non-supercharging state is created, and the rotational speed decreases and the supercharging pressure increases as the rotational speed signal increases. let

Further, when the accelerator opening signal exceeds a predetermined amount, a maximum boost pressure state is created regardless of the rotation speed. The reduction in boost pressure is 1
As the rotational speed increases, the accelerator opening signal decreases by 20 IIv.

[Effects and advantages of the invention]

Below 1. As explained above, according to the present invention, the boost pressure is not controlled according to a function determined only according to the engine speed and the accelerator opening, but also according to the function determined only according to the engine speed and the accelerator opening.
Since the controller is controlled according to the accelerator depression speed, the optimum supercharging IF is always supplied in a step-by-step manner, and when acceleration is required, the engine speed at that time is It is possible to instantly lower the supercharging speed by 1 liter regardless of the situation.

In other words, optimal supercharging control enables smooth driving during normal driving, and also provides comfortable and smooth acceleration response during re-acceleration immediately after engine braking.
can demonstrate.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram of an example of a supercharging device, Fig. 2 is a graph showing the supercharging performance P1 in an embodiment of the present invention, and Fig. 3 is a graph showing the configuration of the present invention. Block [χ, Fig. 4 is a schematic block diagram showing an embodiment of the present invention, Fig. 5 is a circuit diagram thereof, Fig. 6 is a flowchart of the CPU, and Fig. 7 is a diagram showing another embodiment. The schematic configuration diagram, FIG. 8, is a graph showing the relationship between boost pressure and engine speed Ne in one embodiment. , Intake Kelp”/Tsza (Supercharged 4! Ri22・
...Exhaust passage 23, Exhaust bypass passage 24, Waste gate 1 valve (control 1st stage) 40,
,,, CPU (supercharging pressure setting circuit and super candy pressure correction)
Circuit) 41, Crank sensor (engine rotation detection - R stage) 42, Accelerator opening detection 1 stage 60, Circuit (accelerator depression speed detection means) Applicant: Aisin Seiki Co., Ltd. Agent Patent Attorney Asamichi Kato-r-/nf'e Ne10 IE11 Rishi (Kugiko,
4th) March 1980, Director General of the Patent Office, Mr. Kazuinu Wakasugi (September 1981, 3011.1) 2 Title of invention Supercharging control device for internal combustion engine Name (:0
01) Aisin Seiki Co., Ltd. 5 sleeve 11 instructions (with 1
Spontaneous 6 supplementary 11. Number of inventions increased by None 7 Target of extraction Column 8 for detailed explanation of the invention in the specification Contents of compensation
As shown in the attached document (■), the Detailed Description of the Invention column in the specification is amended as follows. 1) Insert a European sentence after "Seru." on page 5, line i17 of the specification. A suitable embodiment of the supercharger system is to arrange a compressor and a fuel supply device in the intake duct between the air cleaner and the engine, and adjust the boost pressure in the intake duct by the control device. In a preferred embodiment, the control device determines the supercharging state in the intake duct according to the relationship between the engine speed and the accelerator opening signal. a line along the increasing direction of the engine rotational speed when the intermediate supercharging area is a dog of the accelerator opening signal, and a line along the increasing direction of the accelerator opening signal when the engine rotational speed is small. A signal is sent that is determined by a region defined by a line along the line and a line connecting these lines, and supplies a boost pressure according to the coordinates (Pij) of the engine rotation speed and the accelerator opening signal. , the conventional two-stage supercharging control cannot necessarily be said to provide the supercharging state that best suits the driving conditions of the vehicle.On the other hand, according to this preferred embodiment of the present invention, the engine speed and acceleration request signal ( (Accelerator opening signal)
By allowing control expressed in the area, jJi
It can be controlled to create a supercharging state that matches both running conditions, and in the intermediate region, the supercharging amount is changed in stages according to the function displayed by the engine speed and acceleration request No. 13. It also has a great fuel saving effect. ” (here)

Claims (1)

[Claims] A reference supercharging pressure is determined based on a supercharger installed in the intake passage, a means for detecting the engine speed, a means for detecting the accelerator opening, and the detected rotational speed signal and the detected accelerator opening signal. A reference supercharging pressure setting circuit that sets the reference supercharging pressure in stages, one stage that controls supercharging based on the output signal of the reference supercharging pressure setting circuit, means for detecting one accelerator depression speed, and this detected depression speed. The reference boost pressure is set to 1 in response to the signal each time! A supercharging control device for an internal combustion engine, which includes a supercharging pressure correction f circuit that increases J1 by 14 times.