JPH0523786Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a device for controlling a nozzle vane of a turbocharger provided with a movable nozzle vane,
More specifically, the present invention relates to a device for controlling the nozzle vane so as not to reduce the boost pressure immediately before acceleration in a vehicle equipped with the supercharger.

[Prior art] Conventionally, a movable nozzle vane is provided in the turbine housing of a supercharger, and when the engine is running at low speeds, the opening of this nozzle vane is narrowed to increase the discharge speed of exhaust gas, thereby increasing the rotation of the turbine wheel. , improves the torque when the engine rotates at low speeds, and when the engine rotates at high speeds,
Opening the nozzle vane according to its rotation speed,
A supercharger that reduces the exhaust gas discharge speed to prevent the turbine wheel rotation from rising too high, and also opens the nozzle vane opening in the low engine load range to lower the engine back pressure and reduce pumping loss. (hereinafter, a turbine configured in this way will be referred to as a "VG turbine").

In a vehicle equipped with this VG turbine, when the gear is changed while driving, the engine speed and load temporarily drop, so the opening area of the nozzle vane opens wide, so the turbine speed decreases and the boost pressure decreases accordingly. This results in a disadvantage that when the gear change is completed and acceleration is started, sufficient engine output is not immediately produced, and acceleration performance can only be achieved gradually.

Therefore, vehicles equipped with VG turbines not only have a poor acceleration feeling when changing gears, but also have actual acceleration delays, which requires improvement.

As a proposal to improve the above-mentioned drawbacks, for example, there is a device proposed in Japanese Utility Model Application Publication No. 59-19928. This invention reduces the area of the turbine nozzle by catching the actuator, which controls the opening of the nozzle vane using fluid pressure, from accelerating based on signals from the engine rotation sensor and engine load sensor. It is intended to improve the However, this idea uses an actuator that operates in two stages by applying fluid pressure to two pistons in the same cylinder arranged in series, and the engine rotation is divided into three stages. The turbine nozzle area is configured to correspond to each number. Therefore, this idea has poor control and still needs to be improved.

Further, as another idea, there is a control device for an exhaust gas turbocharged engine proposed in Japanese Utility Model Application Publication No. 62-29445.

In the turbocharged engine described in this publication, in order to increase the boost pressure, the nozzle vane opening is narrowed and the exhaust gas flow rate is controlled to increase, but as mentioned above, the pumping loss In order to reduce this, it is necessary to take into consideration the back pressure of the engine, so the reality is that the amount by which the nozzle vane opening is narrowed must be limited to a certain degree.

Therefore, the engine output is restricted to the control range of the nozzle vane opening, and especially when rapid acceleration is required, such as when accelerating to overtake, the control limit of the nozzle vane opening There was a problem that the increase in engine output slowed down and it was difficult to obtain sufficient acceleration power.

[Purpose of the invention]

In view of the above problems, the present invention continuously controls the nozzle vane opening of the VG turbine according to the engine speed, and adapts it to both driving conditions, acceleration at start and acceleration during steady running. Moreover, even if the exhaust gas flow area is maximized within the nozzle vane opening adjustment range, the engine will exceed the nozzle vane opening control limit and the engine temperature will be higher than that. It is an object of the present invention to provide a control device for a supercharger that can generate output.

[Structure of the idea]

In order to achieve the above-mentioned object, the control device for a turbocharger of the present invention comprises an actuator for opening and closing movable nozzle vanes of a turbocharger, a speed sensor for detecting the speed of a vehicle equipped with the turbocharger, a clutch sensor, a gear sensor, a boost pressure sensor, and a control device which, based on signals from each of the sensors, sets the nozzle vane opening to a predetermined value when it is detected that the vehicle speed is zero, the clutch is released, and the gear is a starting gear, and reduces the vane opening when it is detected that the vehicle is moving at speed, the gear is an acceleration gear, and the clutch is released, and then controls the actuator to further reduce the nozzle vane opening if a drop in boost pressure is detected and the nozzle vane opening at this time has not reached the control limit, and increases the amount of fuel supplied to the engine if the nozzle vane opening at this time has reached the control limit.

〔Example〕

Since this embodiment is implemented using a conventionally used VG turbine, the main parts of the structure of this VG turbine will first be explained with reference to FIGS. 3 and 4.

FIG. 3 is a sectional view showing the main parts of the supercharger,
FIG. 4 is a sectional view taken along the - line in FIG. 3.

The turbine wheel 1 of this supercharger is constructed by rotating a nozzle vane 4 provided in a nozzle portion 3 of a turbine housing 2 by a drive device 5 provided outside the turbine housing 2.
It is configured such that the flow velocity of exhaust gas flowing out from the nozzle portion 3 to the turbine wheel 1 can be changed.

The configuration of this drive device 5 will be explained. A device for transmitting the operation of an actuator (not shown) to the nozzle vane 4 is housed in the casing 5a.

That is, this device is configured to transmit the rotation of the drive lever 6 driven by the actuator to the rotating shaft 7 that is fixed to the nozzle vane 4 and passes through the thick part 2a of the turbine housing 2. It is something that exists.

A control lever 8 is fixed to the rotating shaft 7, and a free end 8a of the control lever 8 is engaged with a recess 9a provided in the inner circumference of a control ring 9. The lever 10 that rotates the control ring 9 is
Its free end is engaged with a recess 9b provided on the outer periphery of the control ring 9, and the other end is fixed to a rotating shaft 11 provided through the casing 5a. At the other end of this rotating shaft 11,
A drive lever 6 is fixed.

Now, the operation of the nozzle vane 4 will be explained with reference to FIG. 4. When the drive lever 6 is rotated in the clockwise direction, the control ring 9 is rotated in the counterclockwise direction by the lever 10, and the control ring 9 is rotated in the counterclockwise direction by the lever 10. The rotating shaft 7 is rotated counterclockwise by the lever 8, and the nozzle vane 4 is opened.

Now, the configuration of this embodiment for controlling the VG turbine described above is shown in FIG.

The intake port 13 of the turbine housing 2 is connected to an exhaust manifold 15 attached to the engine body 14.
It is connected to the. The drive lever 6 is connected by a link 18 to a drive lever 17 of an actuator 16 consisting of a step motor.

The control device 19 for controlling the actuator 16 includes a clutch sensor 20 that detects the engagement status of the clutch, a transmission sensor (not shown) that detects the gear engagement status of the transmission 21, and a compressor (VG turbine) of the supercharger. It is configured such that detection signals are inputted from a boost pressure sensor (not shown) provided on the discharge side of the engine (not shown) and a rotation sensor (not shown) attached to the engine body 14. ing.

This control device 19 forcibly controls the nozzle vane 4 only when the clutch is disengaged, that is, when no load is applied to the engine body 14.
It is configured to narrow down the Therefore, when the engine body 14 is under load, there is no risk of overboosting occurring. Further, the control device 19 is configured to control the electronic governor 22 using the rotation sensor.

Next, the operation of the control device of this embodiment will be explained with reference to the flowchart shown in FIG.

The control of this embodiment includes (1) the start mode control shown on the left side of FIG. 2, that is, the control activated when the vehicle starts from a stopped state, and (2) the start mode control shown on the right side of FIG. There are two types of driving mode control, for example, control that is activated when accelerating during driving, such as overtaking.

Next, the operation of the control device of this embodiment will be explained.
In addition, in the figure, ~ represents each step of the flowchart.

Note that the control device of this embodiment is programmed in advance to read data from each sensor when performing comparison calculations immediately before each calculation; For the sake of brevity, the description is omitted, and the description of this data reading operation is also omitted in the following explanation.

In the figure, the number of gears is represented by G1, G2, etc. in order from low gear, and the top gear is represented by Gn. or,
α is the nozzle vane opening, θ is the accelerator opening, V
is the speed, the suffix " ₀ " is the setting value of each value, the suffix " ₁ " is a certain time, and the suffix " ₂ " is the time after a preset time has elapsed from the " ₁ ". Represent each.

When the program starts, in step it is determined whether the vehicle is running or not based on detection signals from the rotation sensor and the transmission sensor. In this case, for example, it may be configured to confirm by a signal from a speedometer. In this step, if a negative result is obtained, the step
That is, the process moves to the start mode control, and when a positive result is obtained, the process moves to the step, that is, the running mode control.

<Start mode> In the step, it is determined whether the clutch is disengaged or not, and if a positive result is obtained, the process advances to the step and the gear to be used is used at the time of starting.
It is determined whether it is G1 or G2, and if a positive result is obtained, it is determined in step that the accelerator opening degree θ is less than or equal to the set value θ ₀ . If a positive result is obtained, the process advances to step 1, and the control device operates to reduce the nozzle vane opening to a set value α ₀ in order to obtain sufficient boost pressure when the clutch is engaged and the vehicle starts moving.

In addition, the gear stage in the step is G3 or higher,
If a negative result is obtained, the program returns to step and it is determined again whether or not the clutch is in the OFF state, and if it is determined in step that the accelerator opening is greater than the set value θ ₀ , the program returns to step.

After the nozzle vane opening degree is controlled to a predetermined value in the step, it is determined in the step whether or not the clutch is turned off.If the clutch is not turned on yet and a positive result is obtained, the process returns to the step and the clutch is turned off. If it is turned on and the vehicle is starting, a negative result is obtained and the program returns to step to determine whether the vehicle is in a running state.

<Driving mode> If the vehicle is running and a positive result is obtained in the step, the process proceeds to step where the speed change (V 2 −V 1 ) during the time interval preset in the program is calculated, and the speed change (V ₂ −V ₁ ) is calculated. It is determined whether the value is greater than or equal to a preset value, _V0 , and if the vehicle is running at a constant speed or decelerating, and a negative result is obtained, the process returns to step and continues running. It is determined whether the

In the step, if the vehicle is in an accelerating state and a positive result is obtained, the process proceeds to step, in which it is determined whether the gear is a high-speed traveling gear, that is, Gn or Gn _-1 , and if a positive result is obtained, the process proceeds to step. Return to Also, if the gear used is a low gear and a negative result is obtained, the process advances to step 31, where it is determined whether or not the clutch is off.If the clutch is off and a positive result is obtained, the process advances to step 31, where the nozzle vane opening is adjusted. The process proceeds to the aperture step by a predetermined increment. Also, if the clutch is on and a negative result is obtained, the program returns to step.

In step, the nozzle vane opening is narrowed to increase the boost pressure, and after a while, the boost pressure is detected by the boost pressure sensor in step.

If the boost pressure detected at this time is lower than the boost pressure obtained by narrowing the nozzle vane opening in step and a positive result is obtained, proceed to step and reduce the nozzle vane opening. It is determined whether or not the nozzle vane is in the most constricted state, that is, whether the control limit of the nozzle vane opening has been reached.

If the opening degree of the nozzle vane still has an adjustment range that can be further narrowed down, a negative result is obtained and the process returns to step to narrow down the nozzle vane opening degree.

On the other hand, if it is determined in step that the adjustment of the nozzle vane opening has reached the control limit, a positive result is obtained and the control device controls the nozzle vane opening by increasing the fuel supply amount of the engine. After exceeding the limit and controlling to generate higher engine output, proceed to step.

Also, if the boost pressure has not decreased and a negative result is obtained in the step described above, the program proceeds to the step, where it is determined whether the clutch is off or not, and if the clutch is on and a negative result is obtained, the program is activated. is executed again from the step.

Further, if the acceleration state has not yet been entered and the OFF state is obtained and a positive result is obtained, the program returns to the step and the operation of determining the state of the supercharging pressure is repeated to prevent the supercharging pressure from decreasing.

Therefore, the control in this embodiment is performed when the gear stage is
When changing gears without being shifted up to Gn ₁ or Gn _-1 , that is, when the clutch is disengaged, the nozzle vane is throttled, so there is no risk of boost pressure becoming too high, and the engine load due to clutch off is reduced. Since it is possible to prevent the supercharging pressure from decreasing due to the reduction, sufficient engine output can be obtained immediately upon acceleration, and seamless acceleration can be achieved.

By controlling as described above, the control device of this embodiment can control the
Even while driving, the vehicle is always ready for acceleration, and once the acceleration mode is activated, the nozzle vanes can be controlled to the optimum state immediately.

[Effect of idea]

The supercharger control device of the present invention includes an actuator for opening and closing a movable nozzle vane of a turbo supercharger, a speed sensor that detects the speed of a vehicle equipped with this supercharger, a clutch sensor, a gear position sensor, and a boost. Based on the pressure sensor and signals from each of the sensors, the clutch is disengaged when the speed of the vehicle is zero;
When it is detected that the starting gear is set, the nozzle vane opening is set to a predetermined value, and when it is detected that the vehicle is at a speed and the gear is acceleration and the clutch is disengaged, the vane opening is set to a predetermined value. If a decrease in boost pressure is detected and the nozzle vane opening at this time has not reached the control limit, the actuator is controlled to further narrow the nozzle vane opening, and the nozzle vane opening at this time is Since the present invention includes a control device that increases the amount of fuel supplied to the engine when the amount of fuel supplied to the engine reaches the control limit, the following effects can be achieved.

Even when the exhaust gas flow area is maximized within the nozzle vane opening adjustment range,
By increasing the amount of fuel supplied to the engine, it is possible to exceed the nozzle vane opening control limit and generate engine output higher than that state, so the nozzle vane opening adjustment range is restricted. Acceleration performance can be improved without any problems.

In addition, the nozzle vane opening of the VG turbine can be continuously controlled according to the engine speed, and can be adapted to both acceleration at start and acceleration during steady driving, so the Acceleration performance can be improved regardless of the state.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the configuration of a control device of the present invention according to an embodiment, FIG. 2 is a flowchart for executing control of the control device shown in the previous figure, and FIG. FIG. 4 is a longitudinal cross-sectional view of the main part of the feeder, and FIG. 4 is a cross-sectional view taken along the - line in FIG. 3. 1...Turbine wheel, 2...Turbine housing of a supercharger equipped with a boost pressure sensor, 4...
...Movable nozzle vane, 6...Drive lever, 14...
...An engine body equipped with a rotation sensor, 16...Actuator, 17...Drive lever, 18...Link, 19...Control device, 20...Clutch sensor, 21...Transmission equipped with gear position sensor.

Claims (1)

[Scope of utility model registration request] An actuator for opening and closing the movable nozzle vane of the turbocharger, a speed sensor that detects the speed of the vehicle equipped with this turbocharger, a clutch sensor, a gear position sensor, a boost pressure sensor, and signals from each of the above sensors. Based on this, the nozzle vane opening degree is set to a predetermined value when the speed of the vehicle is zero, the clutch is disengaged, and it is detected that the vehicle is in a starting gear;
When it is detected that the vehicle is at a speed and the gear is in the acceleration stage and the clutch is disengaged, the vane opening is throttled, and then a decrease in boost pressure is detected;
If the nozzle vane opening at this time has not reached the control limit, the actuator is controlled to further reduce the nozzle vane opening, and if the nozzle vane opening at this time has reached the control limit, the actuator is controlled to further reduce the nozzle vane opening. A control device for a supercharger, comprising: a control device for increasing the amount of fuel supplied.