JP6015569B2 - Turbocharger - Google Patents

Description

  The present invention relates to a turbocharger.

  The supercharging engine increases in output as the supercharging pressure increases. On the other hand, if the supercharging pressure becomes too high, control of the fuel injection device cannot catch up and engine blow may occur, and the turbocharger speed may exceed the limit and turbine blow may occur. There is sex. Thus, for example, a waste gate valve disclosed in Patent Document 1 is used to limit the supercharging pressure to a predetermined value or less to prevent engine blow and turbine blow.

  The waste gate valve is a valve that adjusts the amount of exhaust gas flowing into the turbocharger by diverting a part of the exhaust from the engine to the turbocharger, and is transmitted from an actuator attached to the compressor housing via a link mechanism. Opened and closed by power.

JP 2012-057546 A

  By the way, when the temperature of the exhaust gas flowing into the turbocharger rises and the turbine housing becomes hot, the turbine housing expands, and the positional relationship between the actuator and the waste gate valve changes. As a result, the relationship between the operating position of the actuator and the valve opening degree of the waste gate valve changes. Therefore, even if the actuator operates according to the target set based on the required supercharging pressure, a situation occurs in which the opening degree of the waste gate valve varies depending on the temperature of the turbine housing. Therefore, even when feedback control is performed so that the actual supercharging pressure matches the required supercharging pressure, there is a problem that the performance of following the actual supercharging pressure with respect to the required supercharging pressure is low.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a turbocharger that can improve the follow-up performance of the actual supercharging pressure with respect to the required supercharging pressure.

The turbocharger according to the first and second aspects of the present invention includes temperature detecting means capable of detecting the temperature of the turbine housing, and a control device for controlling the operating position of the first actuator connected to the waste gate valve. Yes. The control device includes a first target value calculating means for calculating a first target operating position that is a target value of the operating position of the first actuator based on the required supercharging pressure, and the operating position of the first actuator is the first target operating position. And a first driving means for driving the first actuator so that the first target operating position is corrected based on the temperature of the turbine housing.

For example, the first correction means estimates the first fully closed position, which is the operating position of the first actuator corresponding to the fully closed state of the waste gate valve, based on the temperature of the turbine housing, and the first estimated total which is this estimated value. It can be considered that the first target operation position is corrected according to the closed position. Then, assuming that the first fully closed position when the temperature of the turbine housing is a predetermined temperature is the first reference fully closed position, the first target is equal to the difference between the first estimated fully closed position and the first reference fully closed position. The operating position is preferably offset.
In the first aspect of the present invention, the introduction passage of the turbine housing is divided into a first path and a second path. The turbocharger connects the flow rate adjusting valve capable of opening and closing the second path of the introduction passage, the second actuator attached to the support member, and the second actuator and the flow rate adjusting valve so as to transmit power. And a connecting means. The control device calculates a second target operating position that is a target value of the operating position of the second actuator based on the required supercharging pressure, and sets the second target operating position based on the temperature of the turbine housing. Second correction means for correcting, and second drive means for driving the second actuator so that the operating position of the second actuator becomes the second target operating position.
In the second aspect of the present invention, the temperature detection means estimates the temperature of the turbine housing based on the engine speed and the boost pressure or intake air amount.
The turbocharger according to the third aspect of the present invention includes an engine speed detecting means capable of detecting the engine speed, and a control device for controlling the operating positions of the first actuator and the second actuator. The control device includes a first target value calculating unit that calculates a first target operating position based on the required supercharging pressure, and a first actuator that drives the first actuator so that the operating position of the first actuator becomes the first target operating position. Driving means; second target value calculating means for calculating a second target operating position based on the required supercharging pressure; and second driving the second actuator so that the operating position of the second actuator becomes the second target operating position. Drive means and operating range correction means for narrowing the operating range of the second actuator to the valve closing side as the engine speed is lower.

  Therefore, it is possible to suppress the relationship between the operating position of the first actuator and the valve opening of the waste gate valve from changing due to the temperature of the turbine housing. Therefore, the behavior of the waste gate valve with respect to the required supercharging pressure can be made constant regardless of the temperature of the turbine housing. As a result, the follow-up performance of the actual supercharging pressure with respect to the required supercharging pressure is improved.

It is a figure explaining the schematic structure of the engine system to which the turbocharger by a 1st embodiment of the present invention was applied. It is a figure which shows a turbine housing and a supercharging pressure adjustment mechanism among the turbochargers of FIG. It is a block diagram explaining the function of the control apparatus of FIG. It is a map which shows the relationship between the request | requirement supercharging pressure and a 1st target operation position which the 1st target value calculation means of FIG. 3 uses. It is a map which shows the relationship between the temperature of a turbine housing and the 1st estimated fully closed position which the 1st correction | amendment means of FIG. 3 uses. It is a map which shows the relationship between a request | requirement supercharging pressure and the 1st target operation position after correction | amendment by the 1st correction | amendment means of FIG. It is a map which shows the relationship between the request | requirement supercharging pressure and the 2nd target operation position which the 2nd target value calculation means of FIG. 3 uses. It is a map which shows the relationship between the temperature of a turbine housing and the 2nd estimated fully closed position which the 2nd correction | amendment means of FIG. 3 uses. It is a map which shows the relationship between a request | requirement supercharging pressure and the 2nd target operation position after correction | amendment by the 2nd correction | amendment means of FIG. It is a 1st flowchart explaining the control processing of the control apparatus of FIG. FIG. 4 is a second flowchart illustrating a control process of the control device in FIG. 1. In the first embodiment, when the temperature of the turbine housing is relatively high, it is a time chart showing the change of each value in time series when accelerating so that the load state changes from a light load state to a high load state. . In the first embodiment, when the temperature of the turbine housing is relatively high, it is a time chart showing the change of each value in time series when accelerating so that the load state changes from the light load state to the medium load state. . It is a block diagram explaining the function of the control apparatus of the turbocharger by 2nd Embodiment of this invention. It is a map which shows the relationship between an engine speed and the most open position which the working range correction | amendment means of FIG. 14 uses. It is a map which shows the relationship between a request | requirement supercharging pressure and the 2nd target operation position after correction | amendment by the operation range correction | amendment means of FIG. In 2nd Embodiment, when an engine speed is comparatively low rotation, it is a time chart which shows the change of each value in time series when accelerating so that a load state may change from a light load state to a high load state. . It is a block diagram explaining the function of the control apparatus of the turbocharger by 3rd Embodiment of this invention. It is a map which shows the relationship between an engine speed, a supercharging pressure, and the temperature of a turbine housing which the temperature detection means of FIG. 18 uses. It is a map which shows the relationship between the temperature of a turbine housing, and the 1st estimated fully closed position which the 1st correction | amendment means of the control apparatus of the turbocharger by other embodiment of this invention uses. In other embodiment of this invention, it is a map which shows the relationship between a request | requirement supercharging pressure and the 1st target operation position after a correction | amendment by a 1st correction means. It is a map which shows the relationship between the temperature of a turbine housing, and the 2nd estimated fully closed position which the 2nd correction | amendment means of the control apparatus of the turbocharger by other embodiment of this invention uses. In other embodiment of this invention, it is a map which shows the relationship between a request | requirement supercharging pressure and the 2nd target operation position after correction | amendment by a 2nd correction means.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. In the embodiments, substantially the same components are denoted by the same reference numerals and description thereof is omitted.
(First embodiment)
The turbocharger according to the first embodiment of the present invention is used in the supercharged engine system shown in FIG. First, the supercharged engine system 85 will be described. The supercharged engine system 85 includes an intake system 90, an engine 95, an exhaust system 96, and the turbocharger 10.

  The intake system 90 supplies air sucked from the atmosphere through the air cleaner 91 to the turbocharger 10, and supplies air compressed by the turbocharger 10 to the engine 95 through the throttle 93 and the intake manifold 94 while being cooled by the intercooler 92.

The engine 95 burns the air-fuel mixture supplied from the intake system 90 in the combustion chamber, changes the reciprocating motion of the piston due to the explosive force at the time of combustion to rotational motion by the crankshaft, and outputs it to the drive system. .
The exhaust system 96 supplies exhaust gas emitted from the engine 95 to the turbocharger 10 through the exhaust manifold 97, and exhausts the exhaust gas emitted from the turbocharger 10 to the atmosphere through the muffler 99 while being purified by the catalyst 98.

The turbocharger 10 rotates the turbine wheel 11 using the exhaust gas supplied from the exhaust system 96 and rotationally drives the compressor wheel 12 connected to the turbine wheel 11, thereby supplying the air supplied from the intake system 90. The air is compressed and returned to the intake system 90 again.
In the supercharged engine system 85 configured as described above, the amount of combustible fuel can be increased and the output of the engine 95 can be increased by compressing and increasing the air supplied to the engine 95.

Next, the configuration of the turbocharger 10 will be described with reference to FIGS. 1 and 2. The turbocharger 10 includes a turbine shaft 13, a center housing 14, a turbine wheel 11, a turbine housing 16, a compressor wheel 12, a compressor housing 26, and a supercharging pressure adjustment mechanism 30.
The center housing 14 rotatably supports the turbine shaft 13 via a bearing 15.

The turbine wheel 11 is provided at one end of the turbine shaft 13 and is driven to rotate by exhaust.
The turbine housing 16 includes a storage chamber 17 that stores the turbine wheel 11, a first introduction passage 18 and a second introduction passage 19 for introducing exhaust into the storage chamber 17, and an exhaust that discharges exhaust from the storage chamber 17. The passage 21 has a bypass hole 22 that bypasses the storage chamber 17 and connects the second introduction passage 19 and the discharge passage 21. The bypass hole 22 corresponds to a “bypass passage” recited in the claims. The turbine housing 16 is integrally fixed to the center housing 14.

  As shown in FIG. 2, the first introduction passage 18 and the second introduction passage 19 are partitioned by a partition wall 23. The first introduction passage 18 is always in communication with the exhaust manifold 97 shown in FIG. The second introduction passage 19 can communicate with the first introduction passage 18 through the through hole 24 of the partition wall 23. That is, the communication between the second introduction passage 19 and the exhaust manifold 97 is blocked when the through hole 24 is closed.

  The second introduction passage 19 and the discharge passage 21 are partitioned by a partition wall 25. The bypass hole 22 is a hole that the partition wall 25 has. The communication between the second introduction passage 19 and the discharge passage 21 is blocked when the bypass hole 22 is closed.

As shown in FIG. 1, the compressor wheel 12 is provided at the other end of the turbine shaft 13 and rotates integrally with the turbine wheel 11. The air supplied from the intake system 90 to the compressor housing 26 is compressed as the rotation of the compressor wheel 12 increases.
The compressor housing 26 includes a storage chamber 27 that stores the compressor wheel 12, an introduction passage 28 that introduces intake air into the storage chamber 27, and a discharge passage 29 that discharges compressed air from the storage chamber 27. The compressor housing 26 is integrally fixed to the center housing 14.

  As shown in FIGS. 1 and 2, the supercharging pressure adjustment mechanism 30 includes a waste gate valve 31, a first actuator 35, a first link mechanism 38, a flow rate adjustment valve 44, a second actuator 48, a second link mechanism 52, And a control device 60.

  As shown in FIG. 2, the waste gate valve 31 includes a valve body 32, a rotating shaft 33, and a connection arm 34. The valve body 32 can be seated on the edge of the bypass hole 22. The rotating shaft 33 is rotatably supported by the turbine housing 16, and one end protrudes out of the turbine housing 16. The connection arm 34 connects the rotary shaft 33 and the valve body 32. The waste gate valve 31 is a flap valve that can open and close the bypass hole 22 by the valve body 32 in accordance with the rotational position of the rotary shaft 33.

  The first actuator 35 is a cylinder including a case 36 attached to the compressor housing 26 as shown in FIG. 1 and a rod 37 that reciprocates in the axial direction with respect to the case 36 as shown in FIG. The rod 37 is an output member of the first actuator 35. The compressor housing 26 corresponds to a “support member” recited in the claims.

  The first link mechanism 38 has a first link 39 and a second link 41. One end of the first link 39 is connected to the rod 37 of the first actuator 35 via a pin 42, and can rotate relative to the rod 37 around the pin 42. One end of the second link 41 is connected to the other end of the first link 39 via the pin 43, and can rotate relative to the first link 39 around the pin 43. The other end of the second link 41 is fixed to the rotating shaft 33, and rotates around the rotating shaft 33 integrally with the waste gate valve 31. The first link mechanism 38 connects the rod 37 of the first actuator 35 and the waste gate valve 31 so as to be able to transmit power, and converts the reciprocating motion of the rod 37 in the axial direction into the opening / closing motion of the waste gate valve 31. . The first link mechanism 38 corresponds to “first connecting means” described in the claims.

  As shown in FIG. 2, the flow rate adjusting valve 44 includes a valve body 45, a rotating shaft 46 and a connection arm 47. The valve body 45 can be seated on the edge of the through hole 24. The rotating shaft 46 is rotatably supported by the turbine housing 16, and one end protrudes out of the turbine housing 16. The connection arm 47 connects the rotating shaft 46 and the valve body 45. The flow rate adjusting valve 44 is a flap type valve that can open and close the through hole 24 by a valve body 45 in accordance with the rotational position of the rotary shaft 46.

  The second actuator 48 is a cylinder including a case 49 attached to the compressor housing 26 as shown in FIG. 1 and a rod 51 that reciprocates in the axial direction with respect to the case 49 as shown in FIG. The rod 51 is an output member of the second actuator 48.

  The second link mechanism 52 has a third link 53 and a fourth link 54. One end of the third link 53 is connected to the rod 51 of the second actuator 48 via a pin 55. The third link 53 can rotate relative to the rod 51 around the pin 55. One end of the fourth link 54 is connected to the other end of the third link 53 via a pin 56, and can rotate relative to the third link 53 around the pin 56. The other end of the fourth link 54 is fixed to the rotating shaft 46 and rotates around the rotating shaft 46 integrally with the flow rate adjusting valve 44. The second link mechanism 52 connects the rod 51 of the second actuator 48 and the flow rate adjusting valve 44 so as to be able to transmit power, and converts the reciprocating motion of the rod 51 in the axial direction into the opening / closing motion of the flow rate adjusting valve 44. . The second link mechanism 52 corresponds to “second connecting means” recited in the claims.

  As shown in FIG. 1, the control device 60 is composed of a microcomputer including a CPU, a RAM, a ROM, and the like, and executes a program process based on detection signals of various sensors, thereby causing a first actuator 35 and a second actuator 48. To control the operating position. Detection signals are input to the control device 60 from an engine speed sensor 61, an accelerator opening sensor 62, a pressure sensor 63, a temperature sensor 64, and the like. The engine speed sensor 61 detects an engine speed Ne that is the speed of the engine 95. The accelerator opening sensor 62 detects an accelerator opening Acc that is an operation amount of an accelerator device (not shown). The pressure sensor 63 can detect the pressure in the surge tank as the supercharging pressure Pb. The temperature sensor 64 can detect the temperature T of the turbine housing 16 and corresponds to “temperature detection means” described in the claims.

As shown in FIG. 3, the control device 60 includes a required boost pressure setting unit 65, a first target value calculation unit 66, a first correction unit 67, a first drive unit 68, a second target value calculation unit 69, a second target value calculation unit 66. A correction unit 71 and a second drive unit 72 are provided.
The required supercharging pressure setting means 65 sets a required supercharging pressure Pb (t) that is a required supercharging pressure. In the present embodiment, for example, the required boost pressure Pb (t) is set based on the engine speed Ne, the accelerator opening Acc, and the like.

  The first target value calculation means 66 calculates a first target operating position L1 (t) that is a target value of the operating position of the first actuator 35 based on the required supercharging pressure Pb (t) from the map shown in FIG. To do. The “operation position of the first actuator 35” is the operation position of the rod 37 with respect to the case 36 of the first actuator 35.

  Here, the operating position of the first actuator 35 corresponding to the fully opened state of the waste gate valve 31 is defined as a first fully opened position Lo1, and the operating position of the first actuator 35 corresponding to the fully closed state of the waste gate valve 31 is defined as a first fully closed position. The position is Lc1. In the present embodiment, the first target value calculation means 66 sets the first target operating position L1 (t) to the first fully opened position Lo1 when the required supercharging pressure Pb (t) is equal to or lower than the predetermined first pressure P1. To do. Further, the first target value calculating means 66 determines the first target operating position L1 (t) as the first target operating pressure L1 (t) when the required supercharging pressure Pb (t) is between the first pressure P1 and the predetermined second pressure P2. It is set from the fully open position Lo1 to the first fully closed position Lc1 so that the higher the required supercharging pressure Pb (t), the closer to the first fully closed position Lc1. The second pressure P2 is greater than the first pressure P1. Further, the first target value calculation means 66 sets the first target operating position L1 (t) to the first fully closed position Lc1 when the required supercharging pressure Pb (t) is equal to or higher than the second pressure P2.

  Returning to FIG. 3, the first correction means 67 corrects the first target operating position L <b> 1 (t) based on the temperature T of the turbine housing 16. Specifically, the first correction means 67 first estimates the first fully closed position Lc1 based on the temperature T from the map shown in FIG. In the present embodiment, the supercharging pressure adjustment mechanism 30 has a structure in which the first fully closed position Lc1 changes to the valve opening side as the temperature T increases as shown in FIG.

  Subsequently, when the first fully closed position when the temperature T of the turbine housing 16 is the predetermined temperature T1 is defined as the first reference fully closed position Lc1 (s), the first correction unit 67 determines from the map shown in FIG. A difference ΔL1 between the first estimated fully closed position Lc1 (e), which is the estimated first fully closed position, and the first reference fully closed position Lc1 (s) is calculated. Subsequently, as shown in FIG. 6, the first correction means 67 offsets the first target operation position L1 (t) by the difference ΔL1, and calculates the corrected first target operation position L1 (t) _r. To do.

Returning to FIG. 3, the first driving means 68 drives the first actuator 35 so that the operating position of the first actuator 35 becomes the corrected first target operating position L1 (t) _r.
The second target value calculating means 69 calculates a second target operating position L2 (t) that is a target value of the operating position of the second actuator 48 based on the required supercharging pressure Pb (t) from the map shown in FIG. To do. The “operating position of the second actuator 48” is an operating position of the rod 51 with respect to the case 49 of the second actuator 48.

  Here, the operating position of the second actuator 48 corresponding to the fully opened flow rate adjusting valve 44 is the second fully opened position Lo2, and the operating position of the second actuator 48 corresponding to the fully closed flow rate adjusting valve 44 is the second fully closed position. The position is Lc2. In the present embodiment, the second target value calculating means 69 sets the second target operating position L2 (t) to the second fully opened position Lo2 when the required supercharging pressure Pb (t) is equal to or lower than the second pressure P2. Further, the second target value calculating means 69 determines the second target operating position L2 (t) as the second target operating position L2 (t) when the required supercharging pressure Pb (t) is between the second pressure P2 and the predetermined third pressure P3. Between the fully open position Lo2 and the second fully closed position Lc2, the higher the required supercharging pressure Pb (t), the closer to the second fully closed position Lc2 side. The third pressure P3 is greater than the second pressure P2. Further, the second target value calculating means 69 sets the second target operating position L2 (t) to the second fully closed position Lc2 when the required supercharging pressure Pb (t) is equal to or higher than the third pressure P3.

  Returning to FIG. 3, the second correction means 71 corrects the second target operating position L <b> 2 (t) based on the temperature T of the turbine housing 16. Specifically, the second correction means 71 first estimates the second fully closed position Lc2 based on the temperature T from the map shown in FIG. In the present embodiment, the supercharging pressure adjustment mechanism 30 has a structure in which the second fully closed position Lc2 changes to the valve opening side as the temperature T increases as shown in FIG.

Subsequently, when the second fully closed position when the temperature T of the turbine housing 16 is the predetermined temperature T2 is defined as the second reference fully closed position Lc2 (s), the second correction unit 71 determines from the map shown in FIG. A difference ΔL2 between the second estimated fully closed position Lc2 (e), which is the estimated second fully closed position, and the second reference fully closed position Lc2 (s) is calculated. Subsequently, as shown in FIG. 9, the second correcting means 71 offsets the second target operating position L2 (t) by the difference ΔL2, and calculates the corrected second target operating position L2 (t) _r. To do.
Returning to FIG. 3, the second driving means 72 drives the second actuator 48 so that the operating position of the second actuator 48 becomes the corrected second target operating position L2 (t) _r.

  Next, control processing of the control device 60 will be described based on FIGS. 10 and 11. A series of routines shown in FIGS. 10 and 11 are repeatedly executed at predetermined intervals from when the vehicle main switch is turned on until it is turned off. Various parameters used in the following processing are stored in a storage device such as a RAM as needed, and are updated as needed.

  The routine in FIG. 10 is for controlling the operating position of the first actuator 35. When the routine of FIG. 10 starts, first, in step S101, the required supercharging pressure Pb (t) is set. In the present embodiment, for example, the required boost pressure Pb (t) is set based on the engine speed Ne, the accelerator opening Acc, and the like. After step S101, the process proceeds to step S102.

  In step S102, a first target operating position L1 (t) that is a target value of the operating position of the first actuator 35 is calculated from the map shown in FIG. 4 based on the required supercharging pressure Pb (t). After step S102, the process proceeds to step S103.

  In steps S103, S104, and S105, processing for correcting the first target operating position L1 (t) based on the temperature T of the turbine housing 16 is performed. First, in step S103, the first estimated fully closed position Lc1 (e) is calculated based on the temperature T from the map shown in FIG. Subsequently, in step S104, a difference ΔL1 between the first estimated fully closed position Lc1 (e) and the first reference fully closed position Lc1 (s) is calculated from the map shown in FIG. Subsequently, at step S105, as shown in FIG. 6, the first target operating position L1 (t) is offset by the difference ΔL1, and the corrected first target operating position L1 (t) _r is calculated. After step S105, the process proceeds to step S106.

  In step S106, the first actuator 35 is driven so that the operating position of the first actuator 35 becomes the corrected first target operating position L1 (t) _r. After step S106, the process exits the series of routines shown in FIG.

  The routine of FIG. 11 is for controlling the operating position of the second actuator 48. When the routine of FIG. 11 starts, first, in step S111, the required supercharging pressure Pb (t) is set. In the present embodiment, for example, the required boost pressure Pb (t) is set based on the engine speed Ne, the accelerator opening Acc, and the like. After step S111, the process proceeds to step S112.

  In step S112, a second target operating position L2 (t) that is a target value of the operating position of the second actuator 48 is calculated from the map shown in FIG. 7 based on the required supercharging pressure Pb (t). After step S112, the process proceeds to step S113.

  In steps S113, S114, and S115, a process for correcting the second target operating position L2 (t) based on the temperature T of the turbine housing 16 is performed. First, in step S113, the second estimated fully closed position Lc2 (e) is calculated based on the temperature T from the map shown in FIG. Subsequently, in step S114, a difference ΔL2 between the second estimated fully closed position Lc2 (e) and the second reference fully closed position Lc2 (s) is calculated from the map shown in FIG. Subsequently, in step S115, as shown in FIG. 9, the second target operating position L2 (t) is offset by the difference ΔL2, and the corrected second target operating position L2 (t) _r is calculated. After step S115, the process proceeds to step S116.

  In step S116, the second actuator 48 is driven so that the operation position of the second actuator 48 becomes the corrected second target operation position L2 (t) _r. After step S116, the process exits the series of routines shown in FIG.

  In FIG. 12, when the temperature T of the turbine housing 16 is relatively high, the required supercharging pressure Pb (t) when the load state is accelerated so as to change from the light load state to the high load state, after the correction, First target operating position L1 (t) _r, corrected second target operating position L2 (t) _r, valve opening θ1 of waste gate valve 31, valve opening θ2 of flow rate adjusting valve 44, and actual supercharging The change of the pressure Pb is shown in time series. In FIG. 12, the change of each value in this embodiment is shown by a solid line, and the change of each value in the comparison form is shown by a broken line. In the comparison mode, the target operation position of each actuator is not corrected according to the temperature T.

  The period before time t1 when the required boost pressure Pb (t) starts to change from the required boost pressure P4 to P5 is a steady state, and the required boost pressure Pb (t) and the actual excess pressure are controlled by feedback control. It is assumed that there is no deviation from the supply pressure Pb.

  At time t1, the corrected first target operating position L1 (t) _r starts to change to the valve closing side, and the supercharging pressure Pb starts to increase as the valve opening degree θ1 starts to decrease. At this time, in the present embodiment, it is considered that the first fully closed position Lc1 is changed as shown in FIG. 5 due to the influence that the turbine housing 16 expands and the positional relationship between the first actuator 35 and the waste gate valve 31 moves away. Thus, the first target operating position L1 (t) is corrected. Therefore, the behavior of the waste gate valve 31 with respect to the required supercharging pressure Pb is similar to that when the temperature T is relatively low. Therefore, the supercharging pressure Pb follows the required supercharging pressure Pb (t) without delay.

  In contrast, in the comparative embodiment, the first actuator is driven while the relationship between the operating position of the first actuator and the valve opening of the waste gate valve is changed. Therefore, the time t2 at which the waste gate valve is actually closed in the comparative example is earlier than the time t3 at which the waste gate valve 31 is actually closed in the present embodiment. As a result, in the comparative mode, the supercharging pressure Pb gradually increases from the required supercharging pressure Pb between time t1 and time t2, and the supercharging pressure Pb stagnates between time t2 and time t3. become.

  At time t3, the corrected second target operating position L2 (t) _r starts to change to the valve closing side, and the boost pressure Pb starts to increase as the valve opening degree θ2 starts to decrease. At this time, in the present embodiment, it is considered that the second fully closed position Lc2 is changed as shown in FIG. 8 due to the influence that the turbine housing 16 expands and the positional relationship between the second actuator 48 and the flow rate adjusting valve 44 moves away. Thus, the second target operating position L2 (t) is corrected. Therefore, the behavior of the flow rate adjustment valve 44 with respect to the required supercharging pressure Pb is the same as when the temperature T is relatively low. Therefore, the supercharging pressure Pb follows the required supercharging pressure Pb (t) without delay.

  On the other hand, in the comparative embodiment, the second actuator is driven while the relationship between the operating position of the second actuator and the valve opening degree of the flow rate adjusting valve is changed. For this reason, the time t4 when the flow rate adjustment valve is actually closed in the comparison mode is earlier than the time t5 when the flow rate adjustment valve 44 is actually closed in the present embodiment. As a result, in the comparative form, the supercharging pressure Pb gradually increases from the required supercharging pressure Pb from time t3 to time t4, and the supercharging pressure Pb does not change from time t4 to time t5. become.

In FIG. 13, when the temperature T of the turbine housing 16 is relatively high, the required supercharging pressure Pb (t) when accelerating the load state to change from the light load state to the medium load state, after correction, First target operating position L1 (t) _r, corrected second target operating position L2 (t) _r, valve opening θ1 of waste gate valve 31, valve opening θ2 of flow rate adjusting valve 44, and actual supercharging The change of the pressure Pb is shown in time series. The required supercharging pressure P6 in the medium load state is a value at which the waste gate valve 31 is in the fully closed position when the temperature T is relatively low.
Changes until time t3 are basically the same as those in FIG.

  At time t3, the corrected second target operating position L2 (t) _r starts to change to the valve closing side, and the boost pressure Pb starts to increase as the valve opening degree θ2 starts to decrease. At this time, in the present embodiment, the second target operating position L2 (t) is corrected in consideration of the change in the second fully closed position Lc2 as shown in FIG. Therefore, the supercharging pressure Pb follows the required supercharging pressure Pb (t) without delay.

  On the other hand, in the comparative embodiment, the second actuator is driven while the relationship between the operating position of the second actuator and the valve opening degree of the flow rate adjusting valve is changed. Therefore, the second actuator does not operate immediately after time t3, and operates with a predetermined time delay due to feedback control. Therefore, in the comparative form, the follow-up of the supercharging pressure Pb with respect to the required supercharging pressure Pb (t) is delayed.

As described above, the turbocharger 10 according to the present embodiment has the temperature sensor 64 that can detect the temperature of the turbine housing 16 and the first target operating position L1 of the first actuator 35 according to the temperature T of the turbine housing 16 ( t) and a control device 60 for correcting the second target operating position L2 (t) of the second actuator 48.
Therefore, the behavior of the waste gate valve 31 and the flow rate adjustment valve 44 with respect to the required supercharging pressure Pb can be made constant regardless of the temperature T of the turbine housing 16. Therefore, the follow-up performance of the supercharging pressure Pb with respect to the required supercharging pressure Pb (t) can be improved.

In the first embodiment, the first correction means 67 of the control device 60 estimates the first fully closed position Lc1 of the first actuator 35 based on the temperature T of the turbine housing 16, and the first estimation which is this estimated value. The first target operating position L1 (t) is corrected according to the fully closed position Lc1 (e). Specifically, the first correcting means 67 includes a first reference fully closed position Lc1 (s) that is a first fully closed position when the temperature T of the turbine housing 16 is a predetermined temperature T1, and a first estimated fully closed position. A difference ΔL1 from Lc1 (e) is calculated, and the first target operating position L1 (t) is offset by the difference ΔL1.
Therefore, the operating position of the first actuator 35 when the waste gate valve 31 is fully closed can be controlled more accurately.

Further, in the first embodiment, the second correction means 71 of the control device 60 estimates the second fully closed position Lc2 of the second actuator 48 based on the temperature T of the turbine housing 16, and the second estimation which is this estimated value. The second target operating position L2 (t) is corrected according to the fully closed position Lc2 (e). Specifically, the second correction means 71 includes the second reference fully closed position Lc2 (s) that is the second fully closed position when the temperature T of the turbine housing 16 is the predetermined temperature T2, and the second estimated fully closed position. A difference ΔL2 from Lc2 (e) is calculated, and the second target operating position L2 (t) is offset by the difference ΔL2.
Therefore, the operating position of the second actuator 48 when the flow rate adjusting valve 44 is fully closed can be controlled more accurately.

(Second Embodiment)
A turbocharger according to a second embodiment of the present invention will be described.
As shown in FIG. 14, the control device 75 of the second embodiment has an operating range correction means 76. Assuming that the operating position closest to the valve opening in the operating range of the second actuator 48 is the most open position Lo3, the operating range correction means 76, as shown in FIG. 15 and FIG. The open position Lo3 is corrected to the second fully closed position Lc2 side. That is, the operating range correction unit 76 narrows the operating range of the second actuator 48 toward the valve closing side as the engine speed Ne is lower.

  In FIG. 17, when the engine speed Ne is relatively low, the required supercharging pressure Pb (t) when accelerating the load state to change from the light load state to the high load state, the first target operation after correction Changes in the position L1 (t) _r, the corrected second target operating position L2 (t) _r, the valve opening θ1 of the waste gate valve 31, the valve opening θ2 of the flow rate adjusting valve 44, and the actual supercharging pressure Pb Are shown in time series. In FIG. 17, the change of each value in this embodiment is shown by a solid line, and the change of each value in the comparison form is shown by a broken line. The comparative form is a form in which the most open position Lo3 is not corrected according to the engine speed Ne.

In the present embodiment, by correcting the most opened position Lo3 to the second fully closed position Lc2 side, the operating range that does not contribute to the change in the supercharging pressure Pb is excluded from the operating range of the flow rate adjusting valve 44. The sensitivity in the vicinity of the fully opened flow rate adjusting valve 44 is increased. Therefore, the supercharging pressure Pb is changed immediately at time t2 when the flow rate adjusting valve 44 starts the valve closing operation. Therefore, the supercharging pressure Pb follows the required supercharging pressure Pb (t) without delay.
On the other hand, in the comparative embodiment, since the sensitivity near the fully open flow rate adjusting valve 44 is low, the supercharging pressure Pb does not change immediately at time t2, and the supercharging pressure Pb starts to change with delay at time t3. Therefore, the follow-up performance of the supercharging pressure Pb with respect to the required supercharging pressure Pb (t) is low.

(Third embodiment)
A turbocharger according to a third embodiment of the present invention will be described.
As shown in FIG. 18, the control device 80 of the third embodiment has a temperature detection means 81. The temperature detection means 81 estimates the temperature T of the turbine housing 16 based on the engine speed Ne and the supercharging pressure Pb from a map shown in FIG. 19 obtained experimentally in advance.
According to the third embodiment, it is not necessary to provide a temperature sensor in the turbine housing 16, and the cost can be reduced.

(Other embodiments)
In another embodiment of the present invention, the supercharging pressure adjustment mechanism may have a structure in which the first fully closed position Lc1 changes to the valve closing side as the temperature T of the turbine housing increases. In that case, the first correcting means of the control device first estimates the first fully closed position Lc1 based on the temperature T from the map shown in FIG. Subsequently, the first correction unit calculates a difference ΔL1 between the first estimated fully closed position Lc1 (e) and the first reference fully closed position Lc1 (s). Subsequently, as shown in FIG. 21, the first correction means offsets the first target operating position L1 (t) by the difference ΔL1, and calculates the corrected first target operating position L1 (t) _r. .

  In another embodiment of the present invention, the supercharging pressure adjustment mechanism may have a structure in which the second fully closed position Lc2 changes to the valve closing side as the temperature T of the turbine housing increases. In that case, the second correcting means of the control device first estimates the second fully closed position Lc2 based on the temperature T from the map shown in FIG. Subsequently, the second correction unit calculates a difference ΔL2 between the second estimated fully closed position Lc2 (e) and the second reference fully closed position Lc2 (s). Subsequently, as shown in FIG. 23, the second correcting means offsets the second target operating position L2 (t) by the difference ΔL2, and calculates the corrected second target operating position L2 (t) _r. .

In the second embodiment, the control device 75 has first correction means 67, second correction means 71, and operation range correction means 76. On the other hand, in another embodiment of the present invention, the control device may not have the first correction unit and the second correction unit, but may have only the operating range correction unit.
In another embodiment of the present invention, the connecting means for connecting the first actuator and the waste gate valve may be realized by a configuration other than the link mechanism. In another embodiment of the present invention, the connecting means for connecting the second actuator and the flow rate adjusting valve may be realized by a configuration other than the link mechanism.
In another embodiment of the present invention, the first actuator and the second actuator may output rotational motion.

In another embodiment of the present invention, the first actuator and the second actuator are not limited to the compressor housing, and may be attached to another support member provided integrally with the turbine housing.
In another embodiment of the present invention, the temperature detection means may be configured to estimate the temperature of the turbine housing based on the engine speed and the intake air amount.
The present invention is not limited to the embodiments described above, and can be implemented in various forms without departing from the spirit of the invention.

DESCRIPTION OF SYMBOLS 10 ... Turbocharger 11 ... Turbine wheel 16 ... Turbine housing 22 ... Bypass passage (bypass hole)
31 ... Waste gate valve 35 ... First actuator 38 ... First link mechanism (first connecting means)
60, 75, 80 ... control device 64 ... temperature sensor (temperature detection means)
66... First target value calculation means 67... First correction means 68.

Claims (9)

A rotatable turbine wheel (11);
The accommodation chamber (17) for accommodating the turbine wheel, the first passage (18), and the second passage (19), which are divided into introduction passages (18, 19) for introducing exhaust into the accommodation chamber, the accommodation chamber A turbine housing (16) having a discharge passage (21) for discharging exhaust gas from the exhaust passage, and a bypass passage (22) connecting the introduction passage and the discharge passage while bypassing the storage chamber;
A waste gate valve (31) capable of opening and closing the bypass passage;
A first actuator (35) attached to a support member (26) provided integrally with the turbine housing;
First connection means (38) for connecting the first actuator and the waste gate valve so as to transmit power;
Temperature detecting means (64, 81) capable of detecting the temperature of the turbine housing;
First target value calculating means (66) for calculating a first target operating position that is a target value of the operating position of the first actuator based on a required supercharging pressure that is a required supercharging pressure, a temperature of the turbine housing And a first driving means for driving the first actuator so that the operating position of the first actuator becomes the first target operating position. A control device (60, 80) having (68);
A flow rate adjustment valve (44) capable of opening and closing the second path of the introduction passage;
A second actuator (48) attached to the support member;
Second connection means (52) for connecting the second actuator and the flow rate adjusting valve so as to transmit power;
Equipped with a,
The control device includes a second target value calculating means (69) for calculating a second target operating position that is a target value of the operating position of the second actuator based on the required supercharging pressure, and a temperature of the turbine housing. Based on the second correction means (71) for correcting the second target operating position, and second driving means (72) for driving the second actuator so that the operating position of the second actuator becomes the second target operating position. ) and turbocharger, characterized in that it has a (10). The operating position of the second actuator corresponding to the fully closed flow rate adjusting valve is a second fully closed position,
When the second fully closed position when the temperature of the turbine housing is a predetermined temperature is a second reference fully closed position,
The second correction means estimates the second fully closed position based on the temperature of the turbine housing, and calculates a second estimated fully closed position that is the estimated second fully closed position and the second reference fully closed position. the turbocharger of claim 1 which calculates a difference, characterized in that the offset by the amount the second target operating position of the difference. The turbocharger according to claim 1 or 2 , wherein the temperature detection means (64) is a temperature sensor provided in the turbine housing. A rotatable turbine wheel (11);
A storage chamber (17) that stores the turbine wheel, an introduction passage (18, 19) that introduces exhaust into the storage chamber, a discharge passage (21) that discharges exhaust from the storage chamber, and the storage chamber A turbine housing (16) having a bypass passage (22) that bypasses and connects the introduction passage and the discharge passage;
A waste gate valve (31) capable of opening and closing the bypass passage;
A first actuator (35) attached to a support member (26) provided integrally with the turbine housing;
First connection means (38) for connecting the first actuator and the waste gate valve so as to transmit power;
Temperature detecting means (81) capable of detecting the temperature of the turbine housing;
First target value calculating means (66) for calculating a first target operating position that is a target value of the operating position of the first actuator based on a required supercharging pressure that is a required supercharging pressure, a temperature of the turbine housing And a first driving means for driving the first actuator so that the operating position of the first actuator becomes the first target operating position. A control device (60, 80) having (68);
Equipped with a,
The turbocharger (10) , wherein the temperature detecting means estimates the temperature of the turbine housing based on an engine speed and a supercharging pressure or an intake air amount . The introduction passage of the turbine housing is divided into a first path (18) and a second path (19),
Power can be transmitted between the flow rate adjustment valve (44) capable of opening and closing the second path of the introduction passage, the second actuator (48) attached to the support member, and the second actuator and the flow rate adjustment valve. And second connection means (52) connected to
The control device includes a second target value calculating means (69) for calculating a second target operating position that is a target value of the operating position of the second actuator based on the required supercharging pressure, and a temperature of the turbine housing. Based on the second correction means (71) for correcting the second target operating position, and second driving means (72) for driving the second actuator so that the operating position of the second actuator becomes the second target operating position. The turbocharger according to claim 4 , further comprising: The operating position of the second actuator corresponding to the fully closed flow rate adjusting valve is a second fully closed position,
When the second fully closed position when the temperature of the turbine housing is a predetermined temperature is a second reference fully closed position,
The second correction means estimates the second fully closed position based on the temperature of the turbine housing, and calculates a second estimated fully closed position that is the estimated second fully closed position and the second reference fully closed position. The turbocharger according to claim 5 , wherein a difference is calculated, and the second target operating position is offset by an amount corresponding to the difference. The operating position of the first actuator corresponding to the fully closed state of the waste gate valve is a first fully closed position,
When the first fully closed position when the temperature of the turbine housing is a predetermined temperature is a first reference fully closed position,
The first correction means estimates the first fully closed position based on the temperature of the turbine housing, and calculates a first estimated fully closed position, which is the estimated first fully closed position, and the first reference fully closed position. The turbocharger according to any one of claims 1 to 6 , wherein a difference is calculated, and the first target operating position is offset by an amount corresponding to the difference. A rotatable turbine wheel (11);
A storage chamber (17) for storing the turbine wheel, an introduction passage including a first path (18) and a second path (19) for introducing exhaust into the storage chamber, and a discharge path for discharging the exhaust from the storage chamber (21) and a turbine housing (16) having a bypass passage (22) connecting the introduction passage and the discharge passage while bypassing the storage chamber;
A waste gate valve (31) capable of opening and closing the bypass passage;
A first actuator (35) connected to the waste gate valve so as to be capable of transmitting power, and capable of opening and closing the waste gate valve;
A flow rate adjustment valve (44) capable of opening and closing the second path of the introduction passage;
A second actuator (48) connected to the flow rate adjusting valve so as to be capable of transmitting power, and capable of opening and closing the flow rate adjusting valve;
Engine speed detection means (61) capable of detecting the engine speed;
First target value calculation means (66) for calculating a first target operating position, which is a target value of the operating position of the first actuator, based on a required supercharging pressure that is a required supercharging pressure; First driving means (68) for driving the first actuator so that the operating position becomes the first target operating position, a second value which is a target value of the operating position of the second actuator based on the required supercharging pressure. A second target value calculating means (69) for calculating a target operating position; a second driving means (72) for driving the second actuator so that the operating position of the second actuator becomes the second target operating position; and A control device (75) having operating range correction means for narrowing the operating range of the second actuator to the valve closing side as the engine speed is lower;
A turbocharger (10) comprising: The operating position of the first actuator corresponding to the fully closed state of the waste gate valve is defined as a first fully closed position, and the operating position of the first actuator corresponding to the fully open state of the waste gate valve is defined as a first fully opened position. When the operating position of the second actuator corresponding to the fully closed state of the adjustment valve is the second fully closed position, and the operating position closest to the valve opening side of the operating range of the second actuator is the fully open position,
The first target value calculating means sets the first target operating position to the first fully opened position when the required supercharging pressure is equal to or lower than a predetermined first pressure, and the required supercharging pressure is set to the first pressure. Between the first fully open position and the first fully closed position, and the higher the required supercharging pressure, the first target operating position is between the first fully open position and the predetermined second pressure. When the required supercharging pressure is equal to or higher than the second pressure, the first target operating position is set to the first fully closed position.
The second target value calculating means sets the second target operating position to the most open position when the required supercharging pressure is equal to or lower than the second pressure, and the required supercharging pressure is predetermined from the second pressure. The second target operating position is between the most open position and the second fully closed position, and the higher the required supercharging pressure, the more the second target operating position is The turbocharger according to claim 8 , wherein the second target operating position is set to the second fully closed position when the required supercharging pressure is equal to or higher than the third pressure. .

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