JP2004084545A - Variable turbo supercharger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a variable turbo supercharger capable of actuating a nozzle vane with a small and low-torque actuator. <P>SOLUTION: A plurality of nozzle vanes (21) arranged on a perimeter at equal intervals are halved into two groups. A first connection ring (30a) and a second connection ring (30b) are rotatably arranged on paper vertically in an overlapped fashion, and a half of groove parts (34) of the nozzle vanes (21) are installed at respective semi-perimeter parts out of phase by 180 degrees. First rotation links (23) are fixed at tips of vane shafts (22) fixed to the nozzle vanes (21), and halves of them are engaged with the groove parts (34) of the first connection ring (30a) and the second connection ring (30b), respectively. A second rotation link (24) and an interlocking shaft (25) are fixed to each one of the vane shaft (22) in each group, and connected with a rotary driving type actuator, not shown. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a variable turbocharger provided with a nozzle vane for adjusting a flow rate of exhaust gas flowing into an exhaust turbine.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a method of compressing air and sucking a large amount of air into a cylinder, there is known a turbocharger that operates an exhaust turbine using exhaust energy of an engine to drive a centrifugal compressor. In such a turbocharger, since the exhaust gas of the engine is used, the exhaust gas flow rate decreases in the low-speed rotation region of the engine, the exhaust turbine also rotates at a low speed, and the air may not be sufficiently compressed in the centrifugal compressor. . Therefore, in order to improve such characteristics, an on-off valve is provided in the exhaust gas flow path around the exhaust turbine rotor of the turbocharger, and when the exhaust gas flow rate is small, the on-off valve is closed to close the exhaust gas flow path. A variable turbocharger has been used which increases the flow rate of exhaust gas, increases the rotational speed of an exhaust turbine rotor, and sufficiently compresses air in a centrifugal compressor. There has been proposed a device for operating the above-described on-off valve. One example is disclosed in Japanese Patent Application Laid-Open No. H11-343857.
[0003]
FIG. 9 is a side sectional view of a turbocharger disclosed in Japanese Patent Application Laid-Open No. 11-343857. In FIG. 9, an exhaust-side turbine wheel 51 of a turbocharger 50 is connected to an intake-side turbine wheel 52 by a shaft 53. In the turbocharger main body 54, a substantially annular exhaust supply path 55 for flowing exhaust gas to be supplied to the exhaust-side turbine wheel 51 is formed. A plurality of on-off valves 60 are arranged around the exhaust-side turbine wheel 51 at predetermined intervals in the circumferential direction in the exhaust supply path 55, and are pivotally mounted on a support plate 62 by a pivot shaft 61 (not shown). I have. The support board 62 is annular, is inserted into an opening formed on the back surface of the turbocharger main body 54, and forms a part of the turbocharger main body 54. A lid 56 is attached to the back surface of the turbocharger main body 54 to form a space 63 between the turbocharger main body 54 and the support board 62. The space 63 houses an interlocking device 70 that opens and closes the plurality of on-off valves 60 in an interlocked manner.
[0004]
FIG. 10 is a plan view of the interlocking device 70, as viewed in the direction of arrows EE in FIG. In FIG. 10, an annular pivot ring 71 is rotatably provided in a support board 62. An on-off valve 60 is fixedly provided at the base end of a pivot shaft 61 which is mounted to penetrate the support board 62, and a pivot arm 74 is fixedly provided at the distal end. The pivot ring 71 is provided with a plurality of projections 72 with which the forked portion of the pivot arm 74 engages, and one driving projection 73.
[0005]
FIG. 11 is a cross-sectional view of the actuator 80 that drives the pivot ring 71. In FIG. 11, a connection arm 75 having one end engaged with a driving projection 73 provided on a pivot ring 71 is supported at a substantially central portion by a pivot 76 so as to be swingable. The other end of the connecting arm 75 is engaged with the tip of a rod 81 of an actuator 80, and the lower end of the rod 81 is slidably supported by a housing 82. The housing 82 is divided into an atmospheric pressure chamber 85 and a negative pressure chamber 86 by an operation plate 83 fixed to the rod 81 and a diaphragm 84. The operating plate 83 is urged toward the atmospheric pressure chamber 85 by a spring 87. The negative pressure introducing pipe 90 connected to the negative pressure chamber 86 is connected to a downstream side of a throttle valve 94 provided in the intake passage 91, and the negative pressure introducing pipe 90 has a shutoff valve 92 connected to an electronic control unit 93. Is provided.
[0006]
In the above configuration, when the flow rate of the exhaust gas flowing into the exhaust-side turbine wheel 51 is smaller than a predetermined flow rate, the opening amount of the shut-off valve 92 is increased by the electronic control unit 93, and the larger negative pressure is set to the negative pressure chamber 86. To be introduced. The rod 81 is pulled into the actuator 80 by the negative pressure introduced into the negative pressure chamber 86, causing the connecting arm 75 to swing and the pivot ring 71 to rotate. The pivot 61 is rotated by the movement of the projection 72 and closes the on-off valve 60 by a predetermined amount. As a result, the flow velocity of the exhaust gas flowing into the exhaust-side turbine wheel 51 increases, the rotation speed of the intake-side turbine wheel 52 increases, and the intake air is sufficiently compressed.
[0007]
[Problems to be solved by the invention]
However, in the above configuration, one pivot ring is rotationally driven to rotate all the on-off valves by one actuator including a cylinder operated by a negative pressure. Therefore, there is a problem that the actuator requires a large operating force, and the diameter of the cylinder becomes large because the actuator is operated at a negative pressure, so that a large field is required and the configuration of the device becomes difficult.
[0008]
SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is a variable turbocharger that can operate a nozzle vane (open / close valve) with a small-sized, low-torque actuator, has a small space, and is easy to configure. It is intended to provide a supercharger.
[0009]
Means for Solving the Problems, Functions and Effects
In order to achieve the above object, a first aspect of the present invention is a variable turbocharger, wherein a plurality of nozzle vanes rotatably provided at an exhaust gas inlet of an exhaust turbine rotor, and a base end portion provided at the nozzle vane. A fixed vane shaft, a rotating link fixed to the end of the vane shaft, and the plurality of nozzle vanes are divided into a plurality of groups, and a tip end of the rotating link of each group is respectively provided. It is configured to include a plurality of connection rings that rotate the plurality of vane shafts substantially simultaneously by engaging and rotating, and a plurality of actuators that respectively drive the connection rings.
[0010]
According to the first invention, a plurality of nozzle vanes are divided into a plurality of groups, each group is engaged with a plurality of connecting rings, and an actuator is provided for each connecting ring. Therefore, the operating force of the connecting ring is small, and the output of one actuator may be small. For example, a small electric actuator can be used. Therefore, a compact variable turbocharger that is small, simple in structure, easy in device configuration, and compact can be obtained.
[0011]
According to a second aspect of the present invention, in the first aspect, the actuator is a rotary drive type actuator for rotatingly driving an interlocking shaft provided on one vane shaft for each group.
[0012]
According to the second invention, since the actuator is of a rotary drive type, the interlocking shaft can be directly driven by, for example, an electric motor, the structure is simple, and the entire variable turbocharger can be made compact.
[0013]
In a third aspect based on the first aspect, the actuator is a linear drive type actuator for rotating the connection ring.
[0014]
According to the third aspect, since the actuator is of a linear drive type, the solenoid can be arranged at a position where the heat effect of the exhaust turbine is small by, for example, using a solenoid to rotate the connecting ring via a link device. , Reliability can be improved.
[0015]
In a fourth aspect based on the first, second, or third aspect, each of the plurality of connection rings has a thick portion thicker than other portions at each predetermined circumferential length portion, and the thick portion has the thick portion. A groove is provided for engaging with the rotating link, the thick portion and the other portion are combined so as to face each other, and are rotatable relative to each other at a predetermined angle.
[0016]
According to the fourth invention, all the lengths of the vane shafts connecting the rotary link and the nozzle vane, which are engaged with the groove portions of the connection ring, can be made the same, and the number of component items can be reduced, which is advantageous in management. , The cost can be reduced. In addition, since the actuators are rotatable relative to each other at a predetermined angle, a slight deviation between the actuators when driven by a plurality of actuators is absorbed, and an overload is applied to one actuator to hinder operation. There is no.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a variable turbocharger according to the present invention will be described in detail with reference to the drawings.
[0018]
FIG. 1 is a side sectional view of a variable turbocharger including a nozzle vane connecting device and a driving actuator according to a first embodiment. In FIG. 1, the variable turbocharger 1 includes a charge air compressor 5, an exhaust turbine 10, and a bearing housing 2 connecting the two. The exhaust turbine 10 includes an exhaust-side housing 11 that is provided in the middle of an exhaust flow path of an engine (not shown) and guides outflow and inflow of exhaust gas, and an exhaust turbine rotor 16 housed in the exhaust-side housing 11.
[0019]
The exhaust side housing 11 integrally includes an exhaust inflow portion 12 formed on the outer peripheral side and a substantially cylindrical exhaust outflow portion 13 formed in a central portion. An exhaust-side inner plate 14 is provided inside the exhaust-side housing 11 so as to close the opening on the opposite side of the exhaust-outflow portion 13, and a nozzle portion 15 is formed between the exhaust-inflow portion 12 and the exhaust-outflow portion 13. ing.
[0020]
The exhaust turbine rotor 16 integrally includes a shaft 17 that penetrates the exhaust-side inner plate 14, and the shaft 17 is rotatably supported by the bearing housing 2 via the bearing 3. The impeller 6 of the air supply compressor 5 is attached to the other end of the shaft 17. The flange portion 4 at one end of the bearing housing 2 is fixed by bolts (not shown) in a state of being fitted into the exhaust side housing 11, and forms a connection device chamber 18 with the exhaust side inner plate 14.
[0021]
A plurality of nozzle vanes 21 are arranged in a nozzle portion 15 formed on an outer peripheral portion of the exhaust turbine rotor 16, and a nozzle vane connecting device 20 for simultaneously rotating the plurality of nozzle vanes 21 is accommodated in a connecting device chamber 18. I have.
[0022]
FIG. 2 is a plan view of the nozzle vane connecting device 20 of the first embodiment, as viewed in the direction of arrows AA in FIG. 1, and FIG. 1, 2, and 3, a plurality of nozzle vanes 21 are arranged at equal intervals around the exhaust turbine rotor 16. A first rotation link 23 is fixedly provided at a distal end of a vane shaft 22 having a base end fixed to the nozzle vane 21. The plurality of nozzle vanes 21 are divided into two groups by half, and are engaged with the first connection ring 30a and the second connection ring 30b, respectively.
[0023]
FIG. 4 is a perspective view of the first and second connection rings 30a and 30b. In FIG. 4, the first and second connection rings 30a and 30b each include a thick portion 31 having a substantially semicircular circumference and another thin portion 32 having a substantially semicircular circumference. The thin portion 32 is slidably combined with the thin portion 32 so as to face each other. At this time, a gap S is provided between the stepped portions 33 at the boundary between the thick portion 31 and the thin portion 32. The gap S is, for example, a rotation angle of 2 to 3 degrees. 2, 3, and 4, each of the thick portions 31 of the first and second connection rings 30 a and 30 b is provided with a half of the groove portion 34 of the nozzle vane 21, and each of the first and second connection links 30 a and 30 b has a half of the first rotation link 23. It is engaged with the tip.
[0024]
The first and second connection rings 30a, 30b are rotatably supported by guide rollers 35 attached to the exhaust side inner plate 14. FIG. 5 is a view taken in the direction of the arrows CC in FIG. 2 and 5, the guide roller 35 is composed of a pin 36 and a roller 37 rotatably fitted to the pin 36, and the pin 36 is pressed into the exhaust inner plate 14. The three guide rollers 35 are provided on the circumference, and the roller 37 contacts the outer peripheral portions of the first and second connection rings 30a and 30b, and rotatably supports the first and second connection rings 30a and 30b. ing.
[0025]
Next, the configuration of the connection ring drive unit of the first embodiment will be described. 1, 2, and 3, a second rotation link 24 that engages with the groove 34 is fixed to the vane shaft 22 of one nozzle vane 21 among the nozzle vanes 21 that are grouped. An interlocking shaft 25 is fixed to the second rotation link 24. The distal ends of the pair of interlocking shafts 25 are directly connected to a rotary drive type actuator 41 which is an example of the actuator 40. That is, the connection rings 30a and 30b are directly connected to the rotary drive type actuator 41, respectively. The rotary drive type actuator 41 is an electric motor such as a stepping motor or a DC motor.
[0026]
Next, the operation will be described. 1 and 2, when the flow rate of the exhaust gas passing through the nozzle portion 15 of the exhaust turbine 10 becomes slower than a predetermined speed, the rotary drive type actuator 41 is simultaneously rotated by a predetermined angle according to an instruction from a control device (not shown). The rotated interlocking shaft 25 rotates the nozzle vane 21 through the vane shaft 22 by a predetermined angle, and also rotates the second rotation link 24 by a predetermined angle. One second rotating link 24 rotates the first connecting ring 30a by a predetermined angle, and the other second rotating link 24 rotates the second connecting ring 30b. Accordingly, the first rotation link 23 is rotated about the vane shaft 22. Accordingly, the nozzle vanes 21 fixed to the vane shaft 22 are simultaneously rotated in the same direction and at the same angle, the exhaust gas passage area of the nozzle portion 15 is reduced, the flow velocity is increased, and the exhaust turbine rotor 16 is rotated at high speed. The amount of compressed air by the impeller 6 is increased.
[0027]
When the rotary drive type actuators 41 are simultaneously activated, a slight time shift occurs. This error is absorbed by the gap S provided between the stepped portion 33 of the first connection ring 30a and the stepped portion 33 of the second connection ring 30b. Accordingly, all the nozzle vanes 21 are not rotated by one of the rotary drive type actuators 41, and there is no overload.
[0028]
Since the variable turbocharger according to the present invention has the above-described configuration, it is sufficient that one actuator rotates half of the nozzle vanes. Therefore, the generated torque of the actuator is reduced, and the actuator can be driven by a small electric motor. Therefore, the size of the device is reduced, the configuration of the entire device is simplified, and the variable turbocharger can be made compact.
[0029]
The present invention may have the following configuration in addition to the above embodiment.
Although the actuator is an electric rotary drive type actuator, it may be a fluid drive type such as hydraulic pressure or air.
Although two connecting rings and two actuators are used, three or more connecting rings and actuators may be used.
The guide roller may support the connecting ring with a material having low frictional resistance and high abrasion resistance, such as ceramic or sintered metal. Further, in the above embodiment, the connecting ring is disposed on the outer peripheral side, but may be disposed on the inner peripheral side.
[0030]
FIG. 6 is a configuration diagram of a connection ring driving unit according to the second embodiment. In FIG. 6, a connection pin 42 is provided on the first connection ring 30a. A lever 43 having long holes 44 at both ends is provided swingably by a support pin 45, and one long hole 44 and the connection pin 42 are engaged. A connecting pin 48 provided on a drive shaft 47 of a linear drive type actuator 46 which is another example of the actuator 40 is engaged with the other long hole 44 of the lever 43. The linear drive type actuator 46 as another example of the actuator 40 is, for example, a solenoid. The drive structure of the second connection ring 30b is the same as described above.
[0031]
Next, the operation will be described. When the linear drive actuator 46 is driven in the axial direction, the lever 43 swings about the support pin 45, rotates the first connection ring 30a, and rotates the first rotation link 23 about the vane shaft 22. Then, the plurality of nozzle vanes 21 are simultaneously rotated. The second connection ring 30b is similarly rotated, so that all the nozzle vanes 21 are simultaneously rotated.
[0032]
In the present embodiment, the linear drive type actuator 46 is a solenoid, but may be a fluid drive type such as hydraulic pressure or air.
[0033]
FIG. 7 is a plan view of the nozzle vane connection device 20a according to the second embodiment, and FIG. 8 is a view taken along the line D-D in FIG. The same members as those of the first embodiment are denoted by the same reference numerals, description thereof will be omitted, and only different portions will be described. 7 and 8, the third and fourth connection rings 30c and 30d each having half of the groove portions 34 of the nozzle vane 21 are overlapped with each other by 180 ° out of phase. The first connection link 23 fixed to the vane shaft 22 of the nozzle vane 21 is engaged with the third connection ring 30c, and the fourth rotation ring 23d fixed to the vane shaft 22a of the nozzle vane 21 is engaged with the fourth connection ring 30d. The three rotation links 26 are engaged. The supporting method and the driving method of the third and fourth connecting rings 30c and 30d are the same as those of the first embodiment, and the description is omitted.
[Brief description of the drawings]
FIG. 1 is a side cross-sectional view of a variable turbocharger including a nozzle vane connection device according to a first embodiment of the present invention and a driving actuator.
FIG. 2 is a plan view of the nozzle vane connection device according to the first embodiment of the present invention.
FIG. 3 is a view taken in the direction of arrows BB in FIG. 2;
FIG. 4 is a perspective view of a connection ring according to the first embodiment of the present invention.
FIG. 5 is a view taken in the direction of the arrows CC in FIG. 2;
FIG. 6 is a configuration diagram of a connection ring driving unit according to a second embodiment of the present invention.
FIG. 7 is a plan view of a nozzle vane connection device according to a second embodiment of the present invention.
FIG. 8 is a view as viewed in the direction of arrows DD in FIG. 7;
FIG. 9 is a side sectional view of a conventional variable turbocharger.
FIG. 10 is a plan view of a conventional on-off valve interlocking device.
FIG. 11 is a sectional view of a conventional actuator for driving a pivot ring.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Variable turbocharger, 2 ... Bearing housing, 11 ... Exhaust side housing, 14 ... Exhaust side inner plate, 16 ... Exhaust turbine rotor, 18 ... Connection device chamber, 20, 20a ... Nozzle vane connection device, 21 ... Nozzle vane, 22, 22a vane axis, 23 first rotation link, 24 second rotation link, 25 interlocking axis, 26 third rotation link, 30a first connection ring, 30b second connection ring, Reference numeral 30c: third connection ring, 30d: fourth connection ring, 31: thick portion, 32: thin portion, 33: stepped portion, 34: groove portion, 35: guide roller, 40: actuator, 41: rotary drive type actuator , 46 ... linear drive type actuator.

Claims (4)

In variable turbochargers,
A plurality of nozzle vanes (21) rotatably provided at an exhaust gas inlet of an exhaust turbine rotor (16);
A vane shaft (22, 22a) having a base end fixed to the nozzle vane (21);
A rotating link (23, 24, 26) fixed to the tip of the vane shaft (22, 22a);
The plurality of nozzle vanes (21) are divided into a plurality of groups, and each of the plurality of nozzle vanes (21) is engaged with a tip end of each of the rotating links (23, 24, 26) to rotate. A plurality of connecting rings (30a, 30b, 30c, 30d) for rotating the shafts (22, 22a) substantially simultaneously;
A variable turbocharger, comprising: a plurality of actuators (40) for driving the connection rings (30a, 30b, 30c, 30d). The variable turbocharger according to claim 1,
The variable turbocharger, wherein the actuator (40) is a rotary drive type actuator (41) for rotatingly driving an interlocking shaft (25) provided on one vane shaft (22) for each group. Feeder. The variable turbocharger according to claim 1,
The variable turbocharger, wherein the actuator (40) is a linear drive type actuator (46) for rotating the connection ring (30a, 30b, 30c, 30d). The variable turbocharger according to claim 1, 2 or 3,
Each of the plurality of connecting rings (30a, 30b) has a thick portion (31) thicker than the other portion at each predetermined circumferential length, and the rotating link (23, 24) is provided on the thick portion (31). ), Wherein the thick portion (31) and the other portion are combined so as to face each other, and are rotatable relative to each other by a predetermined angle. Supercharger.

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