JP6922789B2 - Engine supercharger - Google Patents

Description

The present invention relates to an engine supercharger, and more particularly to an engine supercharger that drives a supercharger when the operating state is in a predetermined supercharging region.

Conventionally, an engine with a supercharger in which a portion of the intake passage on the upstream side of the supercharger and a portion on the downstream side of the intercooler are connected by a bypass passage configured to bypass the supercharger has been known. Normally, in this type of engine with a supercharger, the supercharger is driven when the operating state is in a predetermined supercharging region (for example, high rotation or high load region), and when the operating state is in the non-supercharged region. Stop driving the turbocharger.

It is also known that EGR gas containing nitride oxides and blow-by gas containing unburned hydrocarbons are recirculated to the upstream portion of the turbocharger in the intake passage for the purpose of improving the emission property.
When the water contained in the EGR gas or blow-by gas condenses on the upstream side of the turbocharger in the intake passage, condensed water is generated, and the condensed water flows into the turbocharger together with the intake air.

The internal combustion engine of Patent Document 1 includes a technique for removing condensed water generated in an intake passage, and includes a supercharger including a turbine and a compressor, and an EGR that returns a part of exhaust gas to the intake passage via an EGR passage. When the device, a bypass passage that bypasses the compressor in the intake passage, an air bypass valve provided in this bypass passage, and an intake temperature sensor provided in the intake passage are provided, and the intake temperature is lower than the generated temperature of condensed water. An air bypass valve opening means for opening the air bypass valve is provided. As a result, when cold, the air adiabatically compressed by the compressor is circulated through the bypass passage to raise the intake air temperature and promote the evaporation (removal) of the condensed water generated in the intake passage.

A grill shutter that can introduce running wind into the engine room to prevent overheating of the engine is installed at the front end of the vehicle, and the opening of the grill shutter is adjusted to control the introduction state of running wind. Is also known.

Japanese Unexamined Patent Publication No. 2015-129457

When the temperature of the turbocharger is extremely low, the condensed water in the intake passage may freeze in the turbocharger, which may hinder the functioning of the turbocharger. In particular, in the case of a mechanical supercharger in which a transmission belt is wound between a pulley connected to the crankshaft of an engine and a pulley of a turbocharger and driven via the transmission belt, between the rotor and the casing. The rotation of the rotor is hindered by the intervening freezing matter, and there is a concern that problems such as seizure of the transmission belt may occur.

Therefore, when the temperature of the turbocharger is low when the engine is started, the temperature of the turbocharger (inner wall temperature) is raised by forcibly driving the turbocharger even if the operating state is in the non-supercharged region. It is possible to secure the function of the turbocharger by warming it to avoid the occurrence of freezing.
However, forcibly driving the turbocharger deteriorates fuel efficiency, so it is desirable to minimize the forced drive of the turbocharger.
In particular, when traveling with the grill shutter open, the inside of the engine room is cooled by the traveling wind, so it is desirable to adjust the opening of the grill shutter in association with the supercharger temperature.

An object of the present invention is to provide an engine supercharger capable of ensuring the function of a supercharger in cold weather without causing deterioration of fuel efficiency.

The engine supercharger according to claim 1 includes a running wind control valve capable of changing the introduction state of running wind into the engine room of the vehicle, a supercharger provided in the intake passage of the engine, and this supercharger. A drive unit that drives the turbocharger, and a control means that controls the traveling wind control valve and the drive unit. When the operating state of the engine is in a predetermined supercharging region, the supercharger is driven and the operating state is not. In an engine supercharging device including a control means for controlling the drive unit so as to stop driving the supercharger in a supercharging region, the control means has a temperature associated with the supercharger. When it is lower than the first set temperature, the running wind control valve is controlled to the closed side, and when the temperature related to the supercharger is lower than the first set temperature and lower than the second set temperature, the above The running wind control valve is controlled to the closed side, and the drive unit is configured to execute forced drive control of the supercharger even when the operating state of the engine is in a predetermined non-supercharged region. It is characterized by that.

According to this configuration, when the temperature associated with the turbocharger is lower than the first set temperature, the control means controls the traveling wind control valve to the closed side, so that the temperature drop of the turbocharger is suppressed. Therefore, it is possible to reduce the frequency of driving the turbocharger for warming up and suppress the deterioration of fuel efficiency.
When the temperature related to the turbocharger is lower than the first set temperature and lower than the second set temperature, the running wind control valve is controlled to the closed side and the operating state of the engine is predetermined. Since the drive unit executes the forced drive control of the supercharger even when it is in the non-supercharged region, the supercharger is warmed up (heated) while suppressing the temperature drop of the supercharger. It can be promoted to prevent freezing of condensed water in the turbocharger.

According to a second aspect of the present invention, in the first aspect of the present invention, the control means is used when the vehicle speed is equal to or higher than the set vehicle speed even when the temperature associated with the supercharger is lower than the second set temperature. It is characterized in that it is configured to limit the control of the traveling wind control valve to the closed side.
According to this configuration, when the vehicle speed is equal to or higher than the set vehicle speed, the control of the traveling wind control valve to the closed side is restricted to ensure both the function of the turbocharger and the traveling stability of the vehicle. Can be planned.

That is, when the temperature related to the turbocharger is lower than the second set temperature, the temperature of the turbocharger rises when the turbocharger is forcibly driven, and when the vehicle speed is equal to or higher than the set vehicle speed, the turbocharger Since the number of revolutions increases and the temperature rise of the supercharger is promoted, freezing of the supercharger is suppressed even if the running wind control valve is not controlled to the closing side. In this way, when the vehicle speed at which freezing of the turbocharger does not matter is equal to or higher than the set vehicle speed, the running wind can be introduced into the engine room by limiting the control of the running wind control valve to the closed side. It is possible to reduce the flow resistance of the running wind and ensure running stability.

According to the invention of claim 3, in the invention of claim 1 or 2, the drive unit bypasses the supercharger and an electromagnetic clutch capable of controlling the engagement state between the supercharger and the output shaft of the engine. A bypass passage and a bypass valve arranged in the bypass passage are provided, and the control means engages the electromagnetic clutch when the operating state of the engine is in the supercharging region and sets the bypass valve as a target supercharging pressure. The electromagnetic clutch is not engaged and the bypass valve is opened when the operating state of the engine is in the non-supercharged region. When the temperature is lower than the second set temperature, the bypass valve is closed to forcibly drive the supercharger even when the operating state of the engine is in the non-supercharged region.

According to this configuration, the control means does not engage the electromagnetic clutch and opens the bypass valve when the operating state of the engine is in the non-supercharged region, so that the flow path resistance is in the non-supercharged region. It is possible to supply intake air while reducing the amount of air intake.
Further, when the temperature related to the supercharger is lower than the second set temperature, the bypass valve is closed to forcibly drive the supercharger even if the operating state of the engine is in the non-supercharged region. Therefore, warming up (heating) of the turbocharger is promoted, so that the condensed water does not freeze in the turbocharger even when it is cold.

The invention of claim 4 is characterized in that, in the invention of claim 3, the control means engages the electromagnetic clutch and closes the bypass valve when the supercharger is forcibly driven.
According to this configuration, the temperature rise of the supercharger can be promoted by forcibly driving the supercharger.

The invention of claim 5 is the invention of claim 4, wherein the control means determines the temperature related to the supercharger, the parameters related to the supercharging state of the supercharger, and the cooling property of the supercharger. It is characterized in that it is configured to estimate based on the parameters related to.
According to this configuration, the temperature rise of the turbocharger is estimated from the parameters related to the supercharging state of the turbocharger, and the temperature drop of the turbocharger is estimated from the parameters related to the cooling performance of the turbocharger. , The temperature associated with the turbocharger can be estimated accurately.

According to the supercharger of the engine of the present invention, the function of the supercharger in the cold state can be ensured as described above.

It is a schematic block diagram of the supercharging device which concerns on embodiment of this invention. It is a block diagram of the intake / exhaust system of an engine including a supercharging device. It is a perspective view of an engine. It is a vertical cross-sectional view of a main part of an intake system of an engine. It is a perspective view of the grill shutter mounted on the front part of an engine. It is a flowchart of a supercharger control. It is a flowchart of interrupt processing in supercharger control. It is a flowchart of interrupt processing which concerns on a modification. It is a time chart showing a supercharger drive request, a duty rate, and a supercharger rotation speed. It is a time chart which shows a supercharger drive request, a duty rate, and a supercharger rotation speed at the time of forced drive of a supercharger.

Hereinafter, embodiments for carrying out the present invention will be described with reference to FIGS. 1 to 10.
As shown in FIG. 1, the supercharger 1 of the engine of the present embodiment includes a supercharger 2, an electromagnetic clutch 3 for driving the supercharger 2, a bypass valve 4 (referred to as ABV), and the supercharger valve 4. A drive device 5 that can open and close the ABV4, an intake valve 6 that can open and close the intake port, a valve timing variable mechanism (called VVT) 7 that can change the opening and closing timing of this intake valve, and a power train control module 10 (called VVT). PCM) etc. are the main components. A drive motor 9 for driving the grill shutter 8 is connected to the PCM 10.

The PCM 10 can detect an oil temperature sensor 20 that detects the temperature of the lubricating oil of the engine, an engine rotation speed sensor 21, an engine load sensor 22 (throttle opening sensor), and an intake air amount introduced into the engine. The intake air amount sensor 23, the outside temperature sensor 24, the rotation speed sensor 25 of the supercharger 2, the first pressure sensor 26 that can detect the upstream pressure of the supercharger 2, and the downstream pressure of the supercharger 2 can be detected. Various types such as a second pressure sensor 27, a vehicle speed sensor 28, and an opening sensor 29 capable of detecting the opening degree of the grill shutter 8 (see FIG. 5) for adjusting the amount of running wind introduced into the engine room from the front of the vehicle. Sensors are each electrically connected.

First, the outline configuration of an in-line multi-cylinder engine with a supercharger of an automobile will be described.
<Engine intake / exhaust system>
As shown in FIG. 2, in the intake / exhaust system of an engine, 30 is a cylinder forming a combustion chamber of the engine, 31 is an intake passage for introducing intake air into the cylinder 30 via an intake valve 6, and 32 is an exhaust valve from the cylinder 30. It is an exhaust passage for discharging exhaust gas through (not shown).

The intake passage 31 includes an intake amount sensor 23 composed of an airflow sensor, a throttle valve 33 for adjusting the intake amount, a supercharger 2 for compressing the intake air and supplying it to the cylinder 30, from the upstream side to the downstream side. An intercooler 34 for cooling the intake air discharged from the turbocharger 2 is provided. The intake passage 31 includes a bypass passage 35 that bypasses the supercharger 2 and connects the intake passage portion 31a on the upstream side and the intake passage portion 31b on the downstream side of the supercharger 2, and is provided in the middle of the bypass passage 35. ABV4 is provided so that the cross-sectional area of the passage can be changed. A blow-by gas passage 38 for connecting the crank chamber of the engine to the intake passage portion 31a is provided, and the blow-by gas passage 38 is equipped with a PCV 38b which is a differential pressure operation type valve.

The supercharger 2 is driven by the supercharger drive unit when the operating state of the engine is in the predetermined supercharging region, and the drive is stopped when the operating state of the engine is in the non-supercharging region.
The supercharger 2 is assumed to be an internal compression type turbocharger having a high demand for reduction of drive loss, for example, a Rishorum type supercharger composed of two rotors and a casing accommodating these rotors. It may be a blower type roots type turbocharger or the like.

An exhaust purification device 36 for purifying exhaust gas is provided in the exhaust passage 32. An EGR passage 37 is provided that circulates a part of the exhaust gas as EGR gas to the bypass passage 35 from the downstream side of the exhaust purification device 36. The EGR passage 37 is connected to a portion of the bypass passage 35 on the upstream side of the ABV4.

As shown in FIG. 4, the bypass passage 35 branches upward from the intake passage portion 31a on the upstream side of the supercharger 2 and extends to the upper side of the supercharger 2, and the intake passage on the downstream side of the supercharger 2 It is connected to the part 31b. The EGR gas introduction portion 37a into the intake passage 31 by the EGR passage 37 is provided in a portion extending upward of the supercharger 2 in the bypass passage 35. The intercooler 34 is arranged on the lower side of the supercharger 2.
The blow-by gas introduction portion 38a from the blow-by gas passage 38 to the intake passage portion 31a is provided on the upper wall portion on the upstream side of the supercharger 2 and on the downstream side of the throttle valve 33.

<Structure of engine intake system / exhaust system>
This engine is a transverse front intake / rear exhaust engine in which the cylinder row direction (longitudinal direction of the crankshaft) is the vehicle width direction. The exhaust gas purification device 36 has a built-in oxidation catalyst and a particulate filter.
As shown in FIG. 3, the surge tank 39 extends from the side of the engine body in the cylinder row direction and is connected to the intake ports of each cylinder of the engine. The intake manifold includes a surge tank 39 and an intake introduction pipe portion 40 integrated with the surge tank 39, and is made of metal (for example, made of aluminum alloy). The intake introduction pipe portion 40 extends below the surge tank 39.

This engine is a 4-cylinder engine with two intake ports in each cylinder.
The intake manifold includes a total of eight branch intake passages (not shown) corresponding to the two intake ports of each cylinder. Each branch intake passage extends from the surge tank 39 and is fixed to the engine body at a peripheral portion of the branch intake passage extending from the surge tank 39.

The supercharger 2 is a mechanical supercharger driven by an engine output shaft (crankshaft) as a power source, and a rotating shaft is arranged in the cylinder row direction on the front side portion of the surge tank 39. .. As shown in FIG. 4, the supercharger 2 is directly connected to the upstream intake pipe 41 extending in the cylinder row direction. The intake air is introduced into the supercharger 2 from the upstream intake pipe 41. The upstream intake pipe 41 constitutes an intake passage portion 31a on the upstream side of the supercharger 2 in the intake passage 31.

The clutch housing 42 of the supercharger 2 projects on the opposite side of the upstream intake pipe 41 of the supercharger 2. The clutch housing 42 houses an electromagnetic clutch 3 for driving the supercharger 2 on the output shaft of the engine. A transmission belt 44 is wound around a pulley 43 coupled to an input shaft of an electromagnetic clutch 3. The electromagnetic clutch 3 is electrically duty-controlled by the PCM 10, and is completely engaged at a duty rate of 100% and completely released at a duty rate of 0%. The electromagnetic clutch 3, the bypass passage 35, and the ABV 4 correspond to a "driving unit" that drives the turbocharger 2.

As shown in FIG. 3, the transmission belt 44 is wound around a crank pulley 45 coupled to an output shaft of an engine as a power source, a pulley 43 of a supercharger 2, and a pulley 47 coupled to a drive shaft of a water pump 46. Has been done. The idlers 48 and 49 and the tension pulley 50 provide an appropriate tension to the transmission belt 44, and the pulleys 43 and 47 of the turbocharger 2 and the water pump 46 are provided with an appropriate winding angle.

As shown in FIG. 4, the bypass pipe 51 constituting the bypass passage 35 is branched from the upstream intake pipe 41 constituting the intake passage portion 31a on the upstream side of the supercharger 2. The bypass pipe 51 branches from the upper surface side of the upstream intake pipe 41 on the downstream side of the throttle valve 33 provided on the upstream intake pipe 41 and extends obliquely upward toward the upper side of the throttle valve 33. The bypass pipe 51 is curved and folded back from a portion extending diagonally upward so as to be further upward of the turbocharger 2. The bypass pipe 51 extends in the cylinder row direction on the upper side of the turbocharger 2 toward the center side of the surge tank 39 following the folded-back portion 51a.

As shown in FIG. 2, an EGR passage 37 for returning exhaust gas from the exhaust system to the intake system is connected to the downstream side of the folded-back portion 51a of the bypass pipe 51. The EGR passage 37 is adapted to guide the exhaust gas to the intake system from the downstream side of the particulate filter of the exhaust purification device 36. An EGR cooler 52 for cooling the exhaust gas returned to the intake system is provided in the middle of the EGR passage 37.

As shown in FIG. 4, an EGR valve 53 that controls the amount of exhaust gas recirculation is provided in the EGR gas introduction portion 37a, which is a connection portion of the EGR passage 37 in the bypass pipe 51. Further, the ABV 4 is provided in the bypass pipe 51 on the downstream side of the EGR valve 53.

As shown in FIGS. 3 and 4, the supercharging discharge pipe 54, the intercooler 34, and the intake intake pipe portion 40 constitute a downstream intake pipe 55 that guides the intake air from the supercharger 2 to the surge tank 39. ..
The downstream intake pipe 55 has a U shape in which the intercooler 34 is arranged at the lowermost portion as a whole when viewed in the cylinder row direction.

In the configuration of the intake system / exhaust system of the engine, when the supercharger 2 is not driven, the intake air is taken from the intake passage portion 31a on the upstream side of the supercharger 2 shown in FIG. 4 through the bypass passage 35 and the surge tank 39. And is sucked into the cylinder 30. When EGR gas is introduced into the bypass passage 35 from the EGR gas introduction section 37a and blow-by gas is introduced from the blow-by gas passage 38 and the blow-by gas introduction section 38a into the bypass passage 35 or the upstream intake passage section 31a, the EGR gas Moisture contained in the blow-by gas is cooled, and condensed water is generated by dew condensation on the wall surface of the intake passage 31. This condensed water tends to collect at the bottom of the upstream intake passage portion 31a. This condensed water easily enters the gap of the supercharger 2 together with the intake air, and the condensed water that has entered the gap of the supercharger 2 may freeze when the engine is stopped and when it is cold.

As shown in FIG. 1, the PCM 10 controls the operation of the inner wall temperature estimation unit 11 that estimates the inner wall temperature (wall temperature) of the supercharger 2, the supercharger 2, the ABV 4, the intake valve 6, and the grill shutter 8. It includes a control unit 13 and the like. The PCM 10 includes a CPU, a ROM, a RAM, an in-side interface, an out-side interface, and the like. The ROM stores programs and data for various controls, and the RAM is provided with a processing area (work memory) used when the CPU performs arithmetic processing.

First, the inner wall temperature estimation unit 11 will be described.
The inner wall temperature estimation unit 11 estimates the temperature increase amount and the temperature decrease amount of the supercharger 2 respectively, and the inner wall temperature of the supercharger 2 (supercharger) is based on the difference between the estimated temperature increase amount and the temperature decrease amount. The temperature associated with) is estimated. The amount of temperature rise is a parameter related to the supercharging state of the supercharger 2, specifically, the amount of intake air detected by each of the sensors 23 to 27, the outside temperature, the number of revolutions of the supercharger 2, and the supercharger. It is calculated using a predetermined formula based on the upstream pressure and the downstream pressure of 2.
Further, the amount of temperature decrease is calculated using a predetermined calculation formula based on the parameters related to the cooling performance of the turbocharger 2, specifically, the vehicle speed and the grill shutter opening degree detected by the sensors 28 and 29, respectively. Will be done.

Here, as shown in FIG. 5, a shroud 14 is provided on the front portion of the engine arranged at the front end portion of the vehicle, and a plurality of horizontally extending grill shutters are provided on the frame-shaped shroud frame 15 of the shroud 14. 8 (corresponding to a running wind control valve) is rotatably attached around the horizontal axis, and these plurality of grill shutters 8 are rotationally driven by one drive motor 9 from fully closed to fully open. The opening is adjustable. The opening and closing of the grill shutter 8 is controlled according to the vehicle speed and the like, and the amount of running wind introduced into the engine room changes according to the opening degree, which also affects the amount of temperature decrease of the supercharger 2. ..

Next, the control unit 13 will be described.
The control unit 13 has a supercharging area map (not shown) in which the supercharging area is set according to the engine speed and the engine load, and a target supercharging in which the target supercharging pressure is set based on the operating state of the engine in the supercharging area. It has a pressure map (not shown). When the operating state of the engine is in the supercharging region, the control unit 13 engages the electromagnetic clutch 3 and opens and closes the ABV 4 (bypass valve) according to the target supercharging pressure.

At this time, the degree of fastening (duty rate) and the opening degree of ABV4 are set according to the target boost pressure set based on the target boost pressure map. Command signals corresponding to the degree of engagement and the opening degree of the ABV 4 are output to the electromagnetic clutch 3 and the drive device 5, respectively.

As shown in FIG. 9, the control unit 13 rotates the supercharger 2 when the amount of change in the duty rate output to the electromagnetic clutch 3 is equal to or greater than a predetermined value, for example, when the duty rate is changed from 0% to 100%. A control period of an intermediate duty rate (for example, 20%) is provided in order to suppress a sudden change in the number (clutch shock). During normal operation, the higher the duty rate of the electromagnetic clutch 3, the smaller the opening degree of the ABV 4. The control unit 13 disengages the electromagnetic clutch 3 and opens the ABV4 when the operating state of the engine is in the non-supercharged region.

Next, the supercharger control peculiar to the present application will be described with reference to the flowcharts of FIGS. 6 and 7. The flowchart of FIG. 7 is executed in parallel with the control of FIG. 6 by interrupt processing.
In the drawings of FIGS. 6 and 7, Si (i = 1, 2, ...) Indicates each step.
This supercharger control is a control that is constantly executed by the PCM 10 while the engine is operating. First, various signals are read from various sensors 20 to 29 in S1 and in S2, as described above, the inner wall temperature estimation unit 11 The calculation for estimating the S / C wall temperature (the temperature of the turbocharger) is executed.

Next, in S3, it is determined whether or not the S / C operating condition is satisfied (that is, whether or not the operating state of the engine is in the supercharging region) based on the engine speed, the throttle opening, and the supercharging region map. .. If the determination is No, it is determined in S4 whether the S / C wall temperature is less than the first set temperature T1 (for example, 3 ° C), and if the determination is No, the process proceeds to S10 and the determination in S4. If is Yes, it is determined in S5 whether the S / C wall temperature is less than the second set temperature T2 (for example, 0 ° C), and if the determination is Yes, the process shifts to S6, and the determination in S4 is No. If the case and the determination of S5 are No, the process proceeds to S10.

If the determination in S5 is Yes, the forced drive of the turbocharger 2 is executed in the steps S6 and S7. That is, in S6, the electromagnetic clutch 3 is switched to an incompletely engaged state (for example, a duty rate of 20%) to forcibly drive the turbocharger 2, and in the next S7, the ABV4 is closed. FIG. 10 shows an example in which the electromagnetic clutch 3 is incompletely engaged to forcibly drive the supercharger 2, and if there is no freezing in the supercharger 2 at this time, the rotation speed of the supercharger 2 is shown in FIG. Will increase.

In the next S8, it is determined whether or not the S / C rotation speed is smaller than the set rotation speed (that is, whether or not the rotation speed of the supercharger 2 has started up), and the rotation speed of the supercharger 2 is increased due to freezing or the like. If it does not start up, the determination in S8 is Yes, it is determined in S9 that the supercharger 2 is frozen, then in S11, the electromagnetic clutch 3 is switched off, and then the control returns.
Therefore, it is possible to prevent the supercharger 2 from being damaged when the supercharger 2 is frozen or the like.

On the other hand, when the rotation speed of the supercharger 2 rises and the determination of S8 becomes No, the process shifts to S13 and the electromagnetic clutch 3 is engaged at the normal duty rate to promote warming up of the supercharger 2. It is switched to and driven, and then the control returns.
When the determination of S4 is No or the determination of S5 is No, the ABV4 is opened in S10 because there is no risk of freezing of the condensed water in the non-supercharged region, and then S11. In, the electromagnetic clutch 3 is brought into the non-engaged state, and then the control returns.

When the operating state of the engine is in the supercharging region and the determination of S3 is Yes, the ABV4 is opened and closed according to the target supercharging pressure in S12, and then the electromagnetic clutch 3 is set to the normal duty rate (for example, 100) in S13. %) Is switched to the engaged state and driven, after which the control returns.

Next, the interrupt process of FIG. 7 is a control for controlling the opening degree of the grill shutter 8, and when this interrupt process is started, the S / C wall temperature in S20 becomes the first set temperature T1 (for example, 3 °). C) It is determined whether or not it is less than, and if the determination is Yes, the grill shutter 8 is switched to fully closed in S21 and then returns in order to prevent the temperature of the supercharger 2 from dropping due to the running wind.

If the determination in S20 is No, it is determined in S22 whether or not the vehicle speed V is equal to or higher than the set vehicle speed (for example, 100 km / h), and if the determination is Yes, the process proceeds to S24. If the determination in S22 is No, it is determined in S23 whether or not the oil temperature of the lubricating oil is equal to or higher than the set oil temperature (for example, 60 ° C). If the determination is Yes, the process proceeds to S24, and the determination in S23 is No. In the case of, the process proceeds to S25. In S24, in order to prevent the engine from overheating, the grill shutter 8 is switched to full open and then returns. In S25, since it is not necessary to introduce the running wind into the engine room, the grill shutter 8 is switched to fully closed and then returns.

Next, the operation and effect of the supercharging device 1 will be described.
When the wall temperature of the supercharger 2 is lower than the first set temperature T1, the control unit 13 controls the grill shutter 8 to the closed side (fully closed), so that the temperature drop of the supercharger 2 is suppressed. Because of warming up, the frequency of driving the supercharger 2 can be reduced to suppress deterioration of fuel efficiency.

Further, when the wall temperature of the turbocharger 2 is lower than the second set temperature T2 set lower than the first set temperature T1, the grill shutter 8 is controlled to the closed side (fully closed) and the operating state of the engine is controlled. In order to cause the drive unit to execute the forced drive control of the supercharger 2 even when is in the predetermined non-supercharged region, the supercharger 2 is warmed up while suppressing the temperature drop of the supercharger 2. (Temperature rise) can be promoted to prevent freezing of condensed water in the turbocharger 2.

When the operating state of the engine is in the non-supercharged region, the control unit 13 does not engage the electromagnetic clutch 3 and opens the ABV4. Therefore, in the non-supercharged region, the control unit 13 supplies intake air while reducing the flow path resistance. can do.
Further, when the wall temperature of the supercharger 2 is lower than the second set temperature T2, the ABV4 is closed and the supercharger 2 is forcibly driven even if the operating state of the engine is in the non-supercharged region. Since the warming up (heating) of the supercharger 2 is promoted, the condensed water does not freeze in the supercharger 2 even when it is cold.

When the supercharger is forcibly driven, the control unit 13 engages the electromagnetic clutch 3 and closes the ABV4. Therefore, by forcibly driving the supercharger 2, the temperature rise of the supercharger 2 can be promoted.
The control unit 13 estimates the wall temperature of the supercharger 2 based on the parameters related to the supercharging state of the supercharger 2 and the parameters related to the cooling property of the supercharger 2.
Therefore, the amount of temperature rise of the supercharger is estimated from the parameters related to the supercharging state of the supercharger 2, and the amount of temperature drop of the supercharger 2 is estimated from the parameters related to the cooling property of the supercharger 2. , The temperature associated with the turbocharger 2 can be estimated accurately.

Next, an example of partially modifying the embodiment will be described.
1] FIG. 8 shows a modified form of the interrupt processing of FIG. 7, and only the modified steps S30 to S34 will be described.

In S30, it is determined whether or not the wall temperature of the turbocharger 2 is lower than the second set temperature T2. If the determination is Yes, the process proceeds to S31. S25 is executed.
In S31, it is determined whether or not the vehicle speed V is equal to or higher than the set vehicle speed (for example, 100 km / h), and if the determination is Yes, the process proceeds to S33. If the determination in S31 is No, it is determined in S32 whether or not the oil temperature is equal to or higher than the set oil temperature (for example, 60 ° C), if the determination is Yes, the process proceeds to S33, and if the determination in S32 is No, it is determined. Move to S34.

When the determination in S31 is Yes and when the determination in S32 is Yes, the grill shutter 8 is switched to half-open in S33, and then returns. In S34, the grill shutter 8 is switched to fully closed in order to warm up the supercharger 2, and then returns.
In this way, even when the wall temperature of the turbocharger 2 is lower than the set temperature T2, when the vehicle speed V is equal to or higher than the set vehicle speed, the supercharger 2 is restricted by limiting the control of the grill shutter 8 to the closed side. It is possible to achieve both the function of the above and the running stability of the vehicle.

That is, when the wall temperature of the supercharger 2 is lower than the second set temperature T2, the temperature of the supercharger 2 rises when the supercharger 2 is forcibly driven, and the vehicle speed is excessive when the vehicle speed is equal to or higher than the set vehicle speed. Since the rotation speed of the turbocharger 2 increases and the temperature rise of the turbocharger 2 is promoted, freezing of the turbocharger 2 is suppressed even if the grill shutter 8 is not controlled to the closing side. In this way, when the vehicle speed at which freezing of the supercharger 2 does not matter is equal to or higher than the set vehicle speed, the running wind is introduced into the engine room by limiting the control of the grill shutter 8 to the closed side. It is possible to reduce the flow resistance of the running wind and ensure running stability.

2] In the above embodiment, the turbocharger temperature is estimated based on the parameters related to the supercharged state of the supercharger and the parameters related to the cooling property of the supercharger, and the parameter related to the supercharged state of the supercharger is the intake amount. , The outside temperature, the number of revolutions of the turbocharger, the upstream pressure and the downstream pressure of the turbocharger have been described, but at least one of the five elements may be used. Further, the amount of temperature rise may be estimated by combining at least one of the above elements with elements other than the five elements.
Similarly, although the example in which the parameters related to the cooling property of the turbocharger are the vehicle speed and the opening degree of the grill shutter have been described, at least one of the two elements may be used. Further, the amount of temperature decrease may be estimated by a combination of at least one of the above elements and an element other than the two elements.

3] In the above-described embodiment, an example of a rotary-type turbocharger has been described, but the turbocharger is not limited to a mechanical turbocharger, and an electric turbocharger or a turbocharger capable of driving a blower with an electric motor. It can be generally applied to turbochargers.

4] By omitting the step of S7 in FIG. 5, disengaging the electromagnetic clutch 3 and switching the ABV4 to the valve closed state as in S8, the supercharger 2 is made free-rotatable, and the turbocharger 2 is over-rotated in S9. The rotation speed of the turbocharger 2 may be compared with the set rotation speed.
If there is no freezing in the supercharger 2, the rotation speed of the supercharger 2 will start up, but if there is freezing in the supercharger 2, the rotation speed of the supercharger 2 will not start up, so it is the same as the supercharger control in FIG. The action effect of is obtained. In this case, the forced drive for forcibly driving the supercharger 2 by the intake flow is executed.

5] In addition, a person skilled in the art can carry out the embodiment in a form in which various modifications are added to the embodiment without departing from the spirit of the present invention, and the present invention also includes such modifications. ..

1 Supercharger 2 Supercharger 3 Electromagnetic clutch 4 ABV
8 Grill shutter 9 Drive motor 10 PCM
11 Inner wall temperature estimation unit 13 Control unit 20 Oil temperature sensor 35 Bypass passage

Claims (5)

A running wind control valve that can change the state of introduction of running wind into the engine room of the vehicle, a supercharger provided in the intake passage of the engine, a drive unit that drives the supercharger, and the running wind control. A control means for controlling a valve and the drive unit, which drives the supercharger when the operating state of the engine is in a predetermined supercharging region and when the operating state is a non-supercharging region of the supercharger. In an engine supercharging device provided with a control means for controlling the drive unit so as to stop the drive.
When the temperature related to the supercharger is lower than the first set temperature, the control means controls the traveling wind control valve to the closing side, and the temperature related to the supercharger is higher than the first set temperature. When the temperature is lower than the second set temperature set low, the running wind control valve is controlled to the closed side, and even when the operating state of the engine is in the predetermined non-supercharging region, the driving unit is supercharged. An engine supercharger characterized in that it is configured to perform forced drive control of a turbocharger. The control means limits the control of the traveling wind control valve to the closing side when the vehicle speed is equal to or higher than the set vehicle speed even when the temperature related to the supercharger is lower than the second set temperature. The engine supercharging device according to claim 1, wherein the supercharging device is configured to be the same. The drive unit includes an electromagnetic clutch that can control the engagement state between the turbocharger and the output shaft of the engine, a bypass passage that bypasses the supercharger, and a bypass valve that is arranged in the bypass passage. Prepare,
When the operating state of the engine is in the supercharging region, the control means engages the electromagnetic clutch and opens and closes the bypass valve according to the target supercharging pressure, and when the operating state of the engine is in the non-supercharging region. Is configured to disengage the electromagnetic clutch and open the bypass valve.
When the temperature associated with the supercharger is lower than the second set temperature, the bypass valve is closed to forcibly drive the supercharger even when the operating state of the engine is in the non-supercharged region. The engine supercharging device according to claim 1 or 2, characterized in that it is configured. The engine supercharging device according to claim 3, wherein the control means engages the electromagnetic clutch and closes the bypass valve when the supercharger is forcibly driven. The control means is configured to estimate the temperature associated with the turbocharger based on parameters related to the supercharging state of the turbocharger and parameters related to the cooling performance of the turbocharger. The engine supercharging device according to claim 4.

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