KR100884884B1 - Variable-nozzle mechanism, exhaust turbocharger equipped therewith, and method of manufacturing exhaust turbocharger with the variable-nozzle mechanism - Google Patents

Abstract

Even if the wear on the drive ring support in which the support elements are in reciprocating sliding or rolling contact with each other under high temperature is increased, the drive ring can be supported on the nozzle mount on the second support, and the second support is Ensures that it is always firmly supported on the nozzle mount, the occurrence of eccentric rotation or departure of the drive ring due to excessive wear of the drive ring support as experienced in the prior art, and the error of the relationship between the output of the actuator and the nozzle vane opening An exhaust turbocharger having a variable nozzle mechanism having a failure safety characteristic is provided, which prevents the occurrence of a decrease in engine performance due to a failure of a variable nozzle mechanism, or the like, or a breakage of the variable nozzle mechanism.

Variable nozzle mechanism, exhaust turbocharger, turbine, nozzle vane, variable turbine capacity

Description

VARIABLE-NOZZLE MECHANISM, EXHAUST TURBOCHARGER EQUIPPED THEREWITH, AND METHOD OF MANUFACTURING EXHAUST TURBOCHARGER WITH THE VARIABLE-NOZZLE MECHANISM}

Figure 1 (a) is a partial plan view of a first embodiment of a variable nozzle mechanism according to the present invention, Figure 1 (b) is a cross-sectional view along the line AA of Figure 1 (a), Figure 1 (c) 1A is a cross sectional view taken along the line BB in FIG. 1A, and the lever plate 44 and the pin 45 are removed in FIGS. 1B and 1C.

2 is a longitudinal sectional view of a second embodiment of a variable nozzle mechanism according to the present invention.

3A is a partial longitudinal cross-sectional view of the first embodiment of the exhaust turbocharger with a variable nozzle mechanism according to the present invention, and FIG. 3B is an enlarged detail view of the portion Z of FIG. 3A.

4 is a partial longitudinal sectional view of the second embodiment of the exhaust turbocharger.

FIG. 5A is a partial longitudinal cross-sectional view of the third embodiment of the exhaust turbocharger, and FIG. 5B is an enlarged detail view of the Y portion of FIG. 5A.

FIG. 6A is a partial longitudinal cross-sectional view of the fourth embodiment of the exhaust turbocharger, and FIG. 6B is an enlarged detail view of part X of FIG. 6A.

FIG. 7 is a partial longitudinal sectional view of the third embodiment of the variable nozzle mechanism according to the present invention showing a cross section taken along the line B-B in FIG.

FIG. 8 is a view seen from the direction of arrow A in FIG.

9 is a longitudinal sectional view of a variable displacement exhaust turbocharger to which the variable nozzle mechanism of the present invention is applied.

10 is a partial cutaway plan view of the variable displacement exhaust turbocharger.

The present invention relates to a variable nozzle mechanism of a turbine nozzle applied to an exhaust turbocharger of an internal combustion engine which transmits the operating force of the actuator to the nozzle vane via a drive ring to change the blade angle of the nozzle vane of the exhaust turbocharger. And an exhaust turbocharger provided with a variable nozzle mechanism for varying the capacity of the turbine.

Recently, many internal combustion engines with turbochargers have flow rates of exhaust gas flowing from the engine through the scroll passages to the turbines according to the engine's operating conditions in order to adjust the flow rate of the exhaust gas to meet the optimum operating conditions of the turbocharger. It adopts a variable capacity turbocharger that can be changed.

The variable displacement turbocharger is provided with a variable nozzle mechanism capable of changing the feather angle of the nozzle vane by transmitting actuation forces such as pneumatic actuators and electric motor actuators to the nozzle vanes via a link mechanism.

For example, in such a variable nozzle mechanism as disclosed in Japanese Patent Laid-Open No. Hei 11-223129 (first conventional art) or Japanese Patent Laid-Open No. Hei 6-137109 (second prior art), a high-temperature exhaust gas is provided. Drive members, such as a drive ring and a link plate, which drive nozzle vanes provided in the outlet portion of the scroll passage through which gas flows, are supported by a turbine casing, and the members are in sliding contact or rolling contact with each other without lubrication.

Therefore, the sliding contact or rolling contact is likely to wear. Excessive wear of these components can cause an error in the relationship between the actuator output and the nozzle vane opening, which degrades engine performance and sometimes breaks the variable nozzle mechanism.

Further, a variable nozzle mechanism is also disclosed in Japanese Patent Laid-Open No. 62-139931 (Third Prior Art) or Japanese Patent Laid-Open No. 2000-8870 (Four Prior Art).

In the third conventional technique, the nozzle vane of the variable nozzle mechanism is rotatably supported by the nozzle mount via a nozzle pin for changing the feather angle of the nozzle vane, and the lever plate connecting the drive ring and the nozzle vane is a nozzle vane. Is attached to the nozzle pin on the axially opposite side of the drive ring, the drive ring is connected to the actuator, and the nozzle mount is fixed to the turbine casing with bolts passing through spacers inserted into the gas passages of the turbine casing with nozzle vanes installed. It is.

A plurality of dowel pins are provided so that the flanges of the nozzle mount and bearing housing are bridging and the rollers are supported to rotate at each of the dowel pins to rotate the inner surface of the drive ring on the surface of the rollers. To be supported.

However, according to the third prior art, the nozzle mount supporting the nozzle vane and the lever plate by the nozzle pin is fixed to the turbine casing via the spacer via the bolt. Therefore, when mounting or detaching the variable nozzle mechanism to the exhaust turbocharger or to the exhaust turbocharger, it is necessary to tighten or loosen the bolts to attach or detach the nozzle mount to or from the turbine housing and also attach the drive ring. Or it is necessary to fix or remove the dowel pin to the flange of the bearing housing in order to detach it. Therefore, attaching and detaching the variable nozzle mechanism to the exhaust turbocharger is a time consuming task in the prior art.

In addition, there is a risk of dropping the spacer and the alignment pin when detaching the variable nozzle mechanism, which may damage the turbine.

In the third prior art, since the nozzle mount supporting the nozzle vane and the lever plate by the nozzle pin is fixed to the turbine casing and the drive ring is attached to the flange of the bearing housing by an alignment pin supporting the roller, the variable nozzle mechanism It is not an integral component but a separate structure consisting of a turbine casing side element and a bearing housing side element. Therefore, it is impossible to supply and replace the variable nozzle mechanism as an assembled unit, and replacement of the components of the turbocharger is not easy, and maintenance is deteriorated.

In the fourth prior art, the nozzle vanes are rotatably supported by the nozzle mount on the gas inlet side, the annular nozzle plate is fixed by the nozzle support to the nozzle mount, and each nozzle pin, which is an integral part of each nozzle vane, is a gas. Extending through the holes of the nozzle mount in a direction away from the inlet passage, ie outward of the turbine casing, at each end of each nozzle pin a lever plate is attached, and the drive plate is connected by a connecting pin to the lever plate. The drive plate is driven by an actuator. Thus, an integrated variable nozzle mechanism is constructed.

The drive ring connection located outside the turbine casing is covered with a separate gas outlet casing which is fixed to the turbine casing by bolts.

Further, in the fourth prior art, the nozzle mount has a flange portion at its outer circumference and is inserted into the bore of the turbine housing, has an inner ring portion extending toward the gas outlet side, and a thrust force toward the gas inlet passage. Is endured by the gas inlet side surface of the flange portion with respect to the turbine casing, and the rear end of the inner ring portion is in contact with the gas outlet casing to withstand the thrust towards the gas outlet side.

However, according to the fourth prior art, the drive ring connection of the variable nozzle mechanism is covered with an additional gas outlet casing provided separately from the turbine casing and the rear of the inner ring portion of the nozzle mount makes contact with the inner front surface of the gas outlet casing. Since the front end face of the casing is used to withstand the thrust towards the gas outlet side, the gas outlet casing needs to be provided separately from the turbine casing, resulting in an increase in the number of parts and an increase in the man-hour of assembly. .

Further, according to the fourth prior art, the drive ring connecting portion of the variable nozzle mechanism is covered with the gas outlet casing, and the inner ring portion of the nozzle mount extends toward the gas outlet side, so that the rear end surface of the inner ring portion of the nozzle mount is inside the gas outlet casing. Since the bearing portion of the thrust toward the gas outlet side is brought into contact with the front surface, the length of the gas outlet side including the nozzle mount is extended, and as a result, the entire length of the exhaust turbocharger is extended.

Further, according to the fourth prior art, the side of the flange portion of the nozzle mount and the side of the turbine casing function as the front end surface of the thrust bearing portion facing the gas inlet passage and the extended inner ring portion of the nozzle mount, and the interior of the gas outlet casing. Since the front surface functions as a thrust bearing portion facing the gas outlet, the thrust clearance is uniquely determined depending on the dimensions in the axial direction of the turbine casing, the gas outlet casing, and the nozzle mount, so as to adjust the clearance of the thrust bearing portion. It takes a lot of time.

In view of the above problems, a first object of the present invention is to prevent the occurrence of eccentricity or derailment of the exhaust turbocharger due to excessive wear of the support of the exhaust turbocharger, and the variable nozzle caused by the eccentric movement or derailment. It is an object of the present invention to provide an exhaust turbocharger with a variable turbine capacity which can prevent the engine failure or the variable nozzle mechanism from being damaged due to a failure of the mechanism.

The second object of the present invention is to reduce the working time by facilitating the mounting and detaching of the variable nozzle mechanism, to improve the reliability by not dropping some components during assembly, and to provide a variable nozzle as an assembled unit. It is to provide an exhaust turbocharger with a variable turbine capacity that can be improved in maintainability by facilitating the supply and replacement of the mechanism.

A third object of the present invention is to provide an exhaust turbocharger with a variable turbine capacity, in which a turbine casing can be a single item, the clearance adjustment of the thrust bearing portion of the variable nozzle mechanism is easy, and the number of parts and assembly time are reduced. It is.

The present invention can achieve the above object, the present invention transmits the driving force of the actuator to the nozzle vane rotatably supported by the nozzle mount through a ring assembly including a drive ring, link plate, lever plate, etc. An exhaust turbocharger having a variable turbine capacity for changing a feather angle, wherein the second turbine is provided on the nozzle mount to rotatably support the nozzle ring when the wear loss of the second support reaches a predetermined amount. Capacity exhaust turbocharger.

According to the first means, the variable supporting the drive ring on the nozzle ring which is rotatably supported by a member that is easily worn by repeating rotation of a certain angle range driven by an actuator of the variable nozzle mechanism without lubrication under high temperature. If the wear loss of the component between the components of the nozzle mechanism reaches a certain range, i.e., the allowable amount, the drive ring is supported on the second support of the nozzle mount. In other words, the second support performs a fail-safe function.

Therefore, the drive ring can always be firmly supported on the nozzle mount, and the occurrence of eccentric rotation or derailment of the drive ring due to excessive wear of the drive ring support as experienced in the first or second prior art, the actuator The occurrence of a decrease in engine performance due to a failure of the variable nozzle mechanism such as an error in the relationship between the output of the nozzle and the opening of the nozzle vane, or the occurrence of breakage of the variable nozzle mechanism can be prevented.

The second means is a variable nozzle mechanism of the exhaust turbocharger, in which the driving force of the actuator is transmitted to the nozzle vanes rotatably supported by the nozzle mount so that the feather angle of the nozzle vanes is changed, and the annular nozzle plate is positioned between the nozzle vanes in the circumferential direction. A variable nozzle mechanism is configured to be connected to the nozzle mount by a plurality of nozzle supports, the drive ring being in the axial direction of the turbocharger such that the axial position of the drive ring is limited by a thrust bearing element attached to the nozzle mount. And a variable nozzle mechanism provided on one side of the nozzle mount opposite the nozzle vane and configured as a variable nozzle mechanism assembly, such as a kind of cartridge that is easy to engage or remove from the turbocharger.

The third means provides an exhaust turbocharger having a variable nozzle mechanism in which the driving force of the actuator is transmitted to the nozzle vane rotatably supported by the nozzle mount, and the feather angle of the nozzle vane is changed, wherein the variable nozzle mechanism is a circumference. The annular nozzle plate is connected to the nozzle mount by a plurality of nozzle supports positioned between the nozzle vanes in the direction, and the drive ring is turbocharged such that the axial position of the drive ring is limited by a thrust bearing element attached to the nozzle mount. Is provided on one side of the nozzle mount opposite the nozzle vanes in the axial direction of the variable nozzle mechanism, which is configured as a variable nozzle mechanism assembly such as a kind of cartridge, and the variable nozzle mechanism assembly is provided with an inner circumferential surface of the nozzle mount such that its radial position is determined. Mounted on the bearing housing near the centering position of the The empty casing is mounted to the nozzle mount near the centering position with the outer circumferential surface of the nozzle mount, and the axial position of the variable nozzle mechanism assembly is defined by its side between the bearing housing and the turbine casing, coupling the variable nozzle mechanism to the turbocharger. Or to facilitate removal from the turbocharger.

In the second and third means, the drive ring of the opposing nozzle mount so that the inner circumferential surface of the drive ring is rotatably supported on an outer circumference formed on one side of the nozzle mount facing the nozzle vanes in the axial direction of the turbocharger. Provided on one side, the thrust bearing element is fixed to the opposite end face of the nozzle mount in a plurality of positions, the axial position of the drive ring is limited by the side of the thrust bearing element and the side of the outer circumference of the nozzle mount, The end face of the thrust bearing element is preferably configured to function as a thrust bearing face for the bearing housing.

According to the second and third means, the annular nozzle plate is fixed to the nozzle mount by a plurality of nozzle supports positioned between the nozzle vanes in the circumferential direction such that the axial position of the drive ring is limited by the thrust bearing element fixed to the nozzle mount. Since the drive ring is provided on one side of the nozzle mount opposite the nozzle vane in the axial direction of the turbocharger, the variable nozzle mechanism of the exhaust turbocharger for changing the feather angle of the nozzle vane is configured to constitute a variable nozzle mechanism assembly such as a kind of cartridge. A variable nozzle mechanism assembly having an associated link mechanism attached thereto may be mounted to the bearing housing near the centering position with the inner circumferential surface of the nozzle mount to determine the radial position of the instrument assembly and the turbine casing with the outer circumferential surface of the nozzle mount. Mounted in the nozzle mount from near, bearing howe And the axial position is defined by the side between the turbine casing. Therefore, the variable nozzle mechanism can be easily assembled to the exhaust turbocharger without the need to adjust the link mechanism after mounting and can be removed by releasing only the turbine casing by loosening the bolts securing the turbine casing to the bearing housing.

Therefore, the man-hour for coupling the variable nozzle mechanism to the exhaust turbocharger or removing it from the exhaust turbocharger is greatly reduced compared to the third prior art, and also the fall of several components upon engagement or removal of the mechanism. Generation is completely eliminated, increasing the reliability of the turbocharger.

Further, since the variable nozzle mechanism is configured as a variable nozzle mechanism assembly such as a kind of cartridge, when the variable nozzle mechanism needs to be replaced, the variable nozzle mechanism assembly can be easily supplied and replaced, thereby maintaining the maintainability of the exhaust turbocharger. This is improved.

According to the second and third means, a variable nozzle mechanism configured as a variable nozzle mechanism assembly such as a kind of cartridge is mounted to the bearing housing near the centering position with the inner circumferential surface of the nozzle mount so that its radial position is determined, and the turbine casing is connected to the nozzle Since the exhaust turbocharger is configured to be mounted to the nozzle mount near the centering position with the outer circumferential surface of the mount, and the axial position of the variable nozzle mechanism assembly is defined by its side between the bearing housing and the turbine casing, the drive ring connecting element is An additional gas outlet casing covering and providing a thrust bearing portion need not be provided as in the fourth prior art, and the number of parts is reduced. In addition, the number of parts is reduced compared to the third prior art, thereby reducing the time for assembly.

In the second and third means, the variable nozzle mechanism configured as a variable nozzle mechanism assembly such as a kind of cartridge is mounted to the bearing housing near the centering position with the inner main surface of the nozzle mount so that its radial position is determined, and the variable nozzle mechanism Since the exhaust turbocharger is configured such that the axial position of the assembly is defined by its side between the bearing housing and the turbine casing, the nozzle mount at the inner rear end of the ring portion by covering the drive ring connecting element and forming an extended ring portion of the gas outlet casing. Compared to the fourth prior art, which is provided with an additional gas outlet casing which provides a thrust bearing portion in contact with the gas cylinder, the length of the gas outlet side of the turbocharger can be reduced, and the turbocharger is reduced by the reduction of the overall length of the turbocharger. It can be miniaturized.

Further, according to the second and third means, the variable nozzle mechanism configured as a variable nozzle mechanism assembly such as a kind of cartridge is mounted to the bearing housing near the centering position with the inner peripheral surface of the nozzle mount so that its radial position is determined, and the turbine casing It is mounted to the nozzle mount near the centering position with the outer circumferential surface of the nozzle mount, and the axial position of the variable nozzle mechanism assembly is defined by its side between the bearing housing and the turbine casing, and between the bearing housing and the front part of the nozzle ring. Since the first turbo thrust bearing portion is formed and the exhaust turbocharger is configured such that the second thrust bearing portion is formed between the rear portion of the nozzle mount and the side of the turbine casing, the thrust bearing portion on the gas inlet passage side and the gas outlet side is the turbine casing, the gas. Depending on the outlet casing and the axial dimension of the nozzle mount Contrary to the case of the second prior art, which is uniquely formed and therefore time-consuming to adjust the clearance of the thrust bearing part, the thrust between the variable nozzle mechanism and the turbine casing / bearing housing configured as a variable nozzle mechanism assembly such as a kind of cartridge. The gap can be easily and accurately adjusted according to the finish dimensions of the turbine casing and bearing housing.

In the second and third means, the thrust bearing element is rotatably supported on a cantilever-mounted roller pin on the nozzle mount on a plurality of circumferential positions and the drive ring is rotatable. It is preferable to include a plurality of roller elements that support the inner circumferential surface of the drive ring and at the same time limit the axial position of the drive ring.

By such a configuration, the inner circumferential surface of the drive ring is supported on a roller which is located in the circumferential direction and supported on a pin that is cantilever mounted to the nozzle mount, so that the rotational resistance of the drive ring is small and the drive force of the variable nozzle mechanism is reduced, Miniaturized actuators can be used to drive the variable nozzle mechanism.

In the second and third means, the roller pin supporting the roller element is preferably fixed in a hole through the nozzle mount.

In this way, the depth control of the hole at the time of drilling is unnecessary and the insertion depth of the roller pin can be easily controlled by using a jig. In addition, since the insertion depth of the roller pins can be increased, the strength of the roller pins against the tilting of the roller pins is increased.

In the second and third means, it is preferred that a washer is provided on one side of the nozzle mount facing the roller element supported on the roller pin between the roller element and the nozzle mount.

In this way, the sliding gap of the roller in the axial direction can be adjusted by the thickness of the washer, so that the dimensional precision of the element in contact with the roller in the axial direction is not strictly required, thereby reducing the machining cost. If the sliding surface is excessively worn, it is enough to replace the washers without replacing other components. Therefore, maintenance costs can be reduced.

In the second and third means, the roller pin for supporting the roller element is preferably formed as a roller pin with a washer.

In this case, since the roller pin is formed as a roller pin having a washer portion to be in close contact with the nozzle mount side, the roller pin is strong against the tilting force acting on the roller pin and smooth operation of the roller is ensured.

In the second and third means, each said thrust bearing element functions as a thrust bearing surface pressed into the hole of the nozzle mount and a thrust bearing surface whose bottom surface is connected with the side surface of the drive ring and whose top surface is directed to the bearing housing. It is preferable that it is a nail pin comprised from the head part which functions as a thrust bearing surface.

With this configuration, even if the drive ring is supported on the nozzle mount so that the inner circumferential surface of the drive ring slides on the outer circumference of the nozzle mount, the area where the drive ring is in sliding contact with the axial side surface of the flange portion of the nail pin is small and the drive ring is slippery. It can be driven by a resistor. Also, by changing the insertion depth of the nail pin into the hole of the nozzle mount, the thrust gap, that is, the gap between the side of the drive ring and the axial side of the flange portion of the nail pin, can be easily adjusted, and the thrust The gap can be adjusted with sufficient precision without being affected by the finish dimension precision of the nozzle mount.

In addition, an accurate thrust gap can be obtained by inserting the nail pin until the axial side of the flange portion of the nail pin contacts the surface of the nozzle mount while maintaining the finish axial accuracy of the nozzle mount in good finish. According to the prior art, it is necessary to maintain the accuracy of both the insertion depth of the nail pin and the axial dimension of the nozzle mount in order to obtain an accurate thrust clearance. On the other hand, according to this structure, an accurate thrust clearance can be obtained by maintaining either the precision of the insertion depth of a nail pin, or the precision of the axial dimension of a nozzle mount.

In the second and third means, the variable nozzle mechanism assembly side contacts the boss provided in the bearing housing to define the axial position of the variable nozzle mechanism assembly and the nozzle plate of the variable nozzle mechanism assembly is accommodated in the annular groove formed in the turbine casing. It is preferred that the turbocharger be configured to be supported there.

According to this configuration, the thrust clearance between the bearing housing / turbine casing and the variable nozzle mechanism assembly can be easily and accurately adjusted by changing the protrusion of the boss from the bearing housing.

The fourth means is a method of manufacturing an exhaust turbocharger having a variable nozzle mechanism according to the second and third means for transmitting a driving force of an actuator to a nozzle vane rotatably supported by a nozzle mount to change the feather angle of the nozzle vane. The annular nozzle plate is connected to the nozzle mount by a plurality of nozzle supports positioned between the nozzle vanes in the circumferential direction, and the driving ring is provided on one side of the nozzle mount opposite the nozzle vanes in the axial direction of the turbocharger. The axial position of the ring is defined by a thrust bearing element attached to the nozzle mount to form a variable nozzle mechanism assembly, such as a kind of cartridge, which variable centering with the inner circumferential surface of the nozzle mount such that its radial position is determined. Mounted in the bearing housing near the location, the turbine casing is mounted in the nozzle mount And mounted to the nozzle mount near the centering position with the outer circumferential surface of the drive, so that the variable nozzle mechanism is easily coupled to or removed from the turbocharger.

In the fourth means, the axial position of the variable nozzle mechanism assembly is preferably defined by the sides of the bearing housing and the turbine casing so that the variable nozzle mechanism assembly can be easily mounted or detached from the exhaust turbocharger.

According to the fourth means, since the variable nozzle mechanism is manufactured as a variable nozzle mechanism assembly such as a kind of cartridge and mounted on the exhaust turbocharger, mounting and detachment of the variable nozzle mechanism is simple and easy. The variable nozzle mechanism assembly with associated link mechanism can be mounted to the bearing housing near the centering position with the inner circumferential surface of the nozzle mount, no adjustment of the link mechanism is necessary after mounting, and the turbine casing is centered with the outer circumferential surface of the nozzle mount. It can be mounted in the vicinity of the nozzle mount, and the axial position of the nozzle mount can be defined by the side surfaces of the bearing housing and the turbine casing, so that the variable nozzle mechanism can be easily mounted or detached from the turbocharger. Therefore, the personnel for mounting and detaching the variable nozzle mechanism can be reduced.

In addition, the thrust clearance between the variable nozzle mechanism configured as a variable nozzle mechanism assembly such as a kind of cartridge and the turbine casing / bearing housing can be easily and accurately adjusted according to the finishing dimensions of the turbine casing and bearing housing.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, unless the dimensions, materials, relative positions, etc. of the components of the present embodiment are specifically determined, they should not be interpreted as a description to limit the scope of the present invention.

9 and 10 showing the structure of the variable nozzle type exhaust turbocharger to which the present invention is applied, reference numeral 1 denotes a turbine casing, reference numeral 38 denotes a scroll passage spirally formed on an outer periphery of the inside of the turbine casing 1, Reference numeral 8 is an exhaust gas outlet through which the exhaust gas expanded at the turbine wheel 4 is discharged to the outside of the turbocharger. Reference numeral 2 denotes a compressor housing, and reference numeral 3 denotes a bearing housing connecting the compressor housing 2 and the turbine casing 1 to each other.

Reference numeral 5 denotes a compressor wheel, reference numeral 6 denotes a turbine shaft connecting the turbine wheel 4 and the compressor wheel 5, and reference numeral 7 is inserted into the bearing housing 3 to support the turbine shaft 6. Bearings. Reference numeral 01 denotes a rotation axis of the turbine shaft 6.

Reference numeral 100 denotes a variable nozzle mechanism, reference numeral 40 denotes a nozzle vane, and a plurality of nozzle vanes are located at equal intervals in the circumferential direction on the inner circumferential side of the scroll passage 38, and nozzle pins on each nozzle vane. 42 is integrally formed, and the nozzle pin 42 is rotatably supported by the nozzle mount 41 fixed to the turbine casing 1. The feather angle of the nozzle vane can be changed by the rotation of the nozzle pin 42. Reference numeral 47 denotes a nozzle plate circumferentially connected to the nozzle mount 41 by a plurality of nozzle supports 49 fixed to the nozzle mount 41, and the nozzle plate 47 is an annular shape formed on the turbine casing 1. It is slidably inserted into the groove.

Reference numeral 43 is a ring plate-shaped drive ring, reference numeral 44 is a lever plate for connecting the nozzle vanes 40 to the drive ring 43, and the plurality of lever plates 44 are the plurality of nozzle vanes 40. Is connected to the drive ring 43, and the drive ring 43 is rotatably supported on the nozzle mount 41 of its outer circumference as shown in Figs. 1A to 1C. . The variable nozzle mechanism 100 will be described later.

Reference numeral 45 denotes a control crank, reference numeral 46 denotes a drive lever assembly, and a driving force of an actuator (not shown) is transmitted to the drive ring 43 via the drive lever assembly 46 and the control crank 45. By rotating the drive ring, the nozzle vane 40 rotates and the feather angle of the nozzle vane is changed.

Referring to Figs. 1A to 1C showing a first embodiment of the variable nozzle mechanism 100 according to the present invention, reference numeral 41 denotes a nozzle mount, reference numeral 43 denotes a drive ring, Reference numeral 44 denotes a lever plate connecting the drive ring 43 and the nozzle vane 40, and reference numeral 44a denotes a pin connecting the drive ring 43 and the lever plate 44.

The plurality of roller pins 51 are located in the circumferential direction and fixed to the nozzle mount 41, and the rollers 50 are rotatably supported on the respective roller pins 51. The drive ring 43 is rotatably supported on the nozzle mount 41 of the outer peripheral part of the drive ring 43 via the roller 50.

In this first embodiment of the variable nozzle mechanism, the inner circumferential surface 43a of the drive ring 43 is supported in rolling contact by a roller as shown in Figs. 1A and 1B. In addition, as shown in FIGS. 1A and 1C, the second support surface 52a is provided on the outer circumferential portion 52 of the nozzle mount at the portion where the roller 50 is not attached. The diameter D2 of the outer circumferential portion 52 of the nozzle mount 41 is smaller than the diameter D1 of the outer circumference of the roller 50 that coincides with the inner circumferential surface 43a of the drive ring 43. The radial clearance between the inner circumferential surface 43a of the drive ring 43 and the second support surface 52a of the outer circumferential portion 52 of the nozzle mount 41 is determined to be equal to the maximum allowable wear loss of the component. do.

Since the drive ring 43 rotates in a limited angle range and the contact range between the roller 50 and the inner circumferential surface of the drive ring 43 is limited, the nozzle mount 41 such as the roller 50 and the roller pin 51, etc. The inner circumferential surface and the components constituting the support of the drive ring 43 are excessively worn due to the non-lubricating operating condition under high temperature, so that the wear loss amount of the component is the inner circumferential surface 43a of the drive ring 43 and the nozzle mount ( When the radial clearance gap between the second support surface 52a of the outer circumferential portion 52 of the 41 is reached, a portion where the inner circumferential surface 43a of the drive ring 43 does not contact the roller is the outer circumferential portion of the nozzle mount 41 ( It is directly supported on the second support surface 52a of the 52 by the maximum allowable gap.

Therefore, according to this embodiment, even when wear of the contact portion of the element constituting the support of the drive ring 43 on the nozzle mount 41 increases or breakage of the roller 50 occurs, the drive ring 43 It may be supported on the second support surface 52a of the nozzle mount 41. Therefore, the drive ring 43 is always reliably supported on the nozzle mount 41, and it is possible to avoid the occurrence of failure such as eccentric rotation or derailment of the drive ring 43 due to excessive wear of the drive ring support.

The second support surface can be simply provided by forming an outer circumferential portion 52 that functions as a second support portion on the nozzle mount 41 without having a separate member requiring additional cost.

Referring to Fig. 2 showing the second embodiment of the variable nozzle mechanism 100 according to the present invention, reference numeral 41 denotes a nozzle mount formed in an annular shape, and reference numeral 40 denotes a plurality of nozzle vanes positioned at equal intervals in the circumferential direction. Each nozzle vane 40 is fixed to the nozzle pin 42 fitted to the nozzle mount and is rotatable to change the feather angle of the nozzle vane. Reference numeral 47 denotes an annular plate-shaped nozzle plate and is connected to the nozzle mount 41 by a plurality of nozzle supports 49 fixed in the circumferential direction and fixed to the rear side (gas passage side, right side in the drawing) of the nozzle mount 41. It is.

Reference numeral 43 is a drive ring rotatably supported on the outer circumferential portion of the nozzle mount 41 formed in an annular shape. Reference numeral 51 denotes a roller pin, and each roller pin 51 is inserted to be fixed to each of the plurality of holes 41c which are drilled to the front side (bearing housing side, left side in the drawing) and are located in the circumferential direction. Reference numeral 50 is a roller rotatably supported on the roller pin 51. The roller 50 contacts the inner circumferential surface of the drive ring 43 to support the drive ring 43 in various parts. The roller has flanges 50a formed on both sides thereof, and the inner circumferential surface of the drive ring 43 is accommodated in a groove formed by the flange to maintain the axial position of the drive ring 43.

As described above, the inner circumferential surface of the drive ring 43 is supported at various portions of the drive ring 43 by a plurality of rollers 50 rotatably supported on a cantilevered roller pin 51. Because of this, the resistance to rotation of the drive ring 43 is small, the driving force necessary to drive the variable nozzle mechanism 100 is reduced, and a miniaturized actuator can be used to operate the variable nozzle mechanism.

Reference numeral 44 denotes a lever plate connecting the drive ring 43 and the plurality of nozzle vanes 40 located on the front side (bearing housing side) of the drive ring 43. Each lever plate 44 is fixed to the end of the nozzle pin 42 at which the end of the rotation axis 01 side of the lever plate is fixed to the nozzle vane, as shown in FIGS. 1A and 2. A groove is formed at the other end (outer side in the circumferential direction) of the lever plate, and the connecting pin 44a fixed to the drive ring 43 is engaged with the groove. Therefore, when the drive ring 43 rotates, the lever plate 44 rotates about the center of the nozzle pin 42 axially, so that the nozzle vane fixed to the nozzle pin 42 also rotates. Therefore, the feather angle of the nozzle vane can be changed.

Since the variable nozzle mechanism 100 is configured as an integral variable nozzle mechanism such as a kind of cartridge as shown in Fig. 2, it is easy to supply and supply the variable nozzle mechanism unit when replacement of the variable nozzle mechanism is required. It can be replaced.

3A and 3B show a first embodiment of the exhaust turbocharger together with the first embodiment of the variable nozzle mechanism shown in FIG. In the figure, a plurality of nozzle vanes 40 (see FIG. 9) are located at equal intervals in the circumferential direction inside the scroll passage 38 of the turbine casing 1. The nozzle pin 42 (see Fig. 9) formed integrally with the nozzle vane 40 is rotatably supported by the nozzle mount 41, and the feather angle of the nozzle vane is changed by the rotation of the nozzle pin 42. Can be.

The nozzle mount 41 is attached to the turbine casing 1 with its circumference fitted to the bore 24 of the turbine casing 1 and its inner circumferential surface fitted to the front outer periphery 22 of the bearing housing, and its radial direction The location is determined.

The nozzle mount 41 has a stepped portion at its outer circumference, and the rear side surface of the stepped portion contacts the thrust bearing surface 23 of the turbine casing 1 to restrict the variable nozzle mechanism 100 from sliding toward the gas outlet side.

The nozzle plate 47 connected to the nozzle mount 41 by a plurality of nozzle supports 49 fixed at the nozzle mount 41 at equal intervals in the circumferential direction has an annular groove 48 formed in the turbine casing 1. ) Is slidably fitted.

Reference numeral 20 denotes a boss fixed to the bearing housing 3, with each boss 20 positioned so as to face the respective roller 50. As shown in Fig. 3B, the end face of the boss 20 contacts the end face of the roller pin 51 to restrict the variable nozzle mechanism 100 from sliding toward the bearing housing 3 side, and At the same time, the roller 50 is prevented from derailing, and a slight gap is formed between the end face of the boss 20 and the end face of the roller 50.

9 is a retained back plate between the bearing housing 3 and the nozzle mount 41, 4 is a turbine wheel, 6 is a turbine shaft, 7 is a bearing, and 01 represents the axis of rotation of the turbine shaft 6.

According to this embodiment, the variable nozzle mechanism 100 has a rear side (gas) of the nozzle mount 41 by a plurality of nozzle supports 49 in which the annular plate-shaped nozzle plate 47 is located between the nozzle vanes 40. Configured to be connected to the nozzle mount 41 on the passage side, and the drive ring 43 is provided in the groove of each of the plurality of rollers supported on the roller pin 51 fixed to the nozzle mount 41. Nozzle pin 42 which is attached to the nozzle mount 41 on the front side (bearing housing side) so that the axial position of the drive ring 43 is determined by the roller 50 by accommodating the inner peripheral surface of The lever plates 44 fixed to the engagement with the connecting pin 44a fixed to the drive ring 43, so that the variable nozzle mechanism 100 is configured as an assembly unit such as a kind of cartridge. Therefore, the nozzle mount 41 is fitted around the bore 24 of the turbine casing 1 so that its radial position is determined, and the inner circumferential surface of the nozzle mount 41 is the front part of the bearing housing. By configuring the exhaust turbocharger to be mounted to the turbine casing 1 while being fitted to the outer circumference 22, the rear side of the stepped portion of the outer circumference of the nozzle mount 41 can be removed without removing, replacing, or adjusting the nozzle plate driving link mechanism. In contact with the thrust contact surface 23 of the turbine casing 1 to limit the sliding of the variable nozzle mechanism 100 toward the gas outlet side, the end surface of each roller pin 51 of each boss 20 The variable nozzle mechanism 100 in contact with the end face limits the sliding toward the bearing housing 3 side. The turbine casing 1 can be easily removed simply by removing the bolts securing the turbine casing 1 to the bearing housing 3 and pulling the turbine casing 1.

The gap that limits the axial movement of the thrust bearing portion of the variable nozzle mechanism 100, that is, the gap between the end face of each boss 20 and the end face of each roller 50, is a projection of the boss 20. It can be changed by changing. In this way, precise adjustment of the gap is possible.

Further, as described above, the instrument assembly is mounted to the bearing housing by a centering position 22 with the inner circumferential surface of the nozzle mount so that its radial position is determined, and the turbine casing is centered with the outer circumferential surface 24 of the nozzle mount. Is mounted to the nozzle mount, and forms a first thrust bearing portion between the bearing housing 3 and the front side of the nozzle mount 41 and between the rear side of the nozzle mount 41 and the turbine casing. 23) an axial position of the variable nozzle mechanism assembly is formed between the bearing housing and the turbine casing, so that the variable nozzle mechanism 100 is configured as an assembly unit of the variable nozzle mechanism such as a kind of cartridge, Thrust clearance between the variable nozzle mechanism 100 configured as the assembly unit and the turbine casing 1 / bearing housing 3 Easily and can be adjusted in conformity with the finished dimensions of (1) and the bearing housing (3).

In the second embodiment of the exhaust turbocharger with the variable nozzle mechanism 100 shown in Fig. 4, as shown in Fig. 3A and Fig. 3B, a plurality of holes drilled along the circumferential direction on the front side (bearing housing side). The pin hole 41c is a hole penetrating the nozzle mount of Fig. 4, and the roller pin 51 is inserted inside the hole.

According to this embodiment, since the pin hole 41c is drilled through the nozzle mount 41, it is unnecessary to control the depth of the hole 41c at the time of drilling, and the insertion depth of the roller pin 51 can be adjusted by using a jig. It can be controlled easily.

In addition, since the insertion depth of the roller pin 51 is deeper than in the embodiment shown in Figs. 3A and 3B, the strength of the roller pin 51 with respect to the tilting of the roller pin is increased.

Except for the above, the same and identical components as those shown in Figs. 3A and 3B are denoted by the same reference numerals as in Figs. 3A and 3B.

A third embodiment of an exhaust turbocharger with a variable nozzle mechanism 100 is shown in FIGS. 5A and 5B.

In this embodiment, a spot face 41a is formed around the hole 41c of the nozzle mount 41 so that the washer 53 is fixed between the spot face and the roller 50. The sliding gap in the axial direction of the roller 50 can be adjusted by the thickness of the washer, so that the accuracy of the elements in contact with the roller in the axial direction is not strictly required, thereby reducing the machining cost.

If the sliding surface in contact with the roller 50 is excessively worn, it is sufficient to replace only the washer without replacing other components such as the nozzle mount 41, the roller 50, and the boss 20. Therefore, maintenance costs can be reduced.

Except for the above, the same and identical components as those shown in Figs. 3A and 3B are denoted by the same reference numerals as in Figs. 3A and 3B.

A fourth embodiment of the exhaust turbocharger with the variable nozzle mechanism 100 is shown in Figs. 6A and 6B.

In the present embodiment, the spot surface 41a is formed around the hole 41c of the nozzle mount 41, and the roller pin 51 has a washer, that is, a washer portion 51b formed as shown in Fig. 6B. It is formed as a roller pin provided with. Since the roller pin 51 is provided with the washer part 51b so that the roller pin 51 may be in close contact with the side surface of the nozzle mount 41, the roller pin 51 becomes strong against tilting and the smooth operation of the roller 50 is ensured.

Except for the above, the same and identical components as those shown in Figs. 3A and 3B are denoted by the same reference numerals as in Figs. 3A and 3B.

7 and 8 showing the third embodiment of the variable nozzle mechanism of the present invention are not provided with the roller pin 51 and the roller 50 shown in Figs. 2 to 6A and 6B. The inner circumferential surface 43a of the drive ring 43 makes it possible to slide on the outer circumferential portion 41d of the nozzle mount 41.

A plurality of nail pins 60 each having a shaft portion and a head portion or a flange portion inserted into the hole of the nozzle mount 41 are located in the circumferential direction, and the shaft side surface 60c of the flange portion of the nail pin 60 is a drive ring. It faces the side of 43 and functions as a thrust bearing surface, and the upper end surface 60b of the flange part faces the lever plate 44.

The axial position of the drive ring 43 is determined between the axial side surface 60c of the flange portion of the nail pin 60 and the front side surface 41e of the outer circumference of the nozzle mount 41, and the drive ring can be rotated between them. Can be.

According to this embodiment, the drive ring 43 is supported on the nozzle mount so that the inner circumferential surface 43a of the drive ring slides on the outer circumferential portion 41d of the nozzle mount 41, but the drive ring 43 is a nail pin ( The surface in sliding contact with the axial side surface 60c of the flange portion 60 is small so that the drive ring 43 can be driven with a small sliding resistance.

Further, by changing the insertion depth of the nail pin 60 in the hole of the nozzle mount 41, a thrust gap, that is, between the side surface of the drive ring 43 and the axial side 60c of the flange portion of the nail pin 60, is provided. The gap of can be easily adjusted, and the thrust gap can be adjusted with sufficient precision without being influenced by the finish dimension precision of the nozzle mount 41.

On the other hand, the nail pin 60 is inserted until the axial side surface 60c of the flange portion of the nail pin 60 comes into contact with the surface of the nozzle mount 41 while maintaining the finish dimension accuracy of the nozzle mount 41 well. By this, an accurate thrust gap can be obtained. According to the prior art, it is necessary to maintain both the insertion depth of the nail pin and the accuracy of the nozzle mount dimension in order to obtain an accurate thrust clearance. On the other hand, according to this embodiment, an accurate thrust clearance can be obtained by maintaining either the accuracy of the insertion depth of the nail pin or the accuracy of the nozzle mount.

According to the present invention, when the wear of the first support of the drive ring reaches the allowable wear loss, the drive ring is supported on the second support. Therefore, even if the wear of the drive ring support increases in the state where the support elements are in reciprocating sliding contact or rolling contact with each other under high temperature without lubrication, the drive ring can be supported on the nozzle mount on the second support, which is the present invention. Means that the failsafe features are included in the variable nozzle mechanism.

According to this feature, the drive ring is always correctly supported on the nozzle mount, the occurrence of eccentric rotation or derailment of the drive ring due to excessive wear of the drive ring support as experienced in the prior art, between the output of the actuator and the nozzle vane opening The occurrence of a decrease in engine performance or the breakage of the variable nozzle mechanism due to a failure of the variable nozzle mechanism such as an error in the relationship can be prevented.

Further, according to the present invention, the variable nozzle mechanism configured as a variable nozzle mechanism assembly such as a kind of cartridge is mounted to the bearing housing near the centering position with the inner circumferential surface of the nozzle mount so that its radial position is determined, and the turbine casing is Variable mounted to the nozzle mount near the centering position with the outer circumferential surface, the axial position of the variable nozzle mechanism assembly being defined by their sides between the bearing housing and the turbine casing, with the associated link mechanism attached to which adjustment is unnecessary after mounting. The nozzle mechanism can be easily coupled to the exhaust turbocharger and can be removed by removing only the turbine casing by loosening the bolts securing the turbine casing to the bearing housing.

Therefore, the incidence for coupling the variable nozzle mechanism to the exhaust turbocharger or removing it from the exhaust turbocharger is greatly reduced compared to the third prior art, and the occurrence of the fall of some components upon the engagement or removal of the mechanism is completely eliminated. The reliability of the turbocharger is increased.

Since the variable nozzle mechanism is configured as a variable nozzle mechanism assembly such as a kind of cartridge, when the replacement of the variable nozzle mechanism is required, the variable nozzle mechanism assembly can be easily supplied and replaced, and the maintainability of the exhaust turbocharger is improved. .

According to the invention, the exhaust turbocharger is configured such that a variable nozzle mechanism configured as a variable nozzle mechanism assembly, such as a kind of cartridge, is mounted to a bearing housing near its centering position with the inner circumferential surface of the nozzle mount so that its radial position is determined, and the turbine The casing is mounted to the nozzle mount near the centering position with the outer circumferential surface of the nozzle mount, and the drive ring connection of the variable nozzle mechanism is defined because the axial position of the variable nozzle mechanism assembly is defined by their sides between the bearing housing and the turbine casing. The element is covered with a bearing housing and a turbine casing. Therefore, it is not necessary to have an additional gas outlet casing and the number of parts is reduced, thereby reducing the time for assembly.

In addition, since the total length of the exhaust turbocharger can be reduced by reducing the length of the gas outlet side, miniaturization of the exhaust turbocharger can be realized.

Further, according to the present invention, the thrust clearance between the variable nozzle mechanism configured as a variable nozzle mechanism assembly such as a kind of cartridge and the turbine casing and bearing housing can be easily and accurately adjusted according to the finishing dimensions of the turbine casing and the bearing housing.

Claims (1)

The driving force of the actuator is transmitted to a nozzle vane rotatably supported by the nozzle mount through a ring assembly including a drive ring, a lever plate, and the like, and the exhaust turbine of the variable turbine capacity changing the feather angle of the nozzle vane by the variable nozzle mechanism. Charger, The drive ring is supported to rotate on the nozzle mount by a first support portion, and a second support portion on the nozzle mount to rotatably support the drive ring when the wear loss of the first support portion reaches a predetermined amount. More equipped, The first support portion is composed of a plurality of rollers provided in the circumferential direction on the nozzle mount, and the second support portion is worn on the outer circumferential surface of a portion where the roller of the nozzle mount is not provided, when the first support portion is worn by a certain amount. And an outer circumferential portion of the nozzle mount fitted to the inner circumferential surface of the drive ring.

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