JP2009133847A - Method and device for dynamic measurement of imbalance of turbine rotor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an improved method for the measurement of the imbalance of a turbine rotor of an exhaust gas turbocharger. <P>SOLUTION: In the method for the dynamic measurement of the imbalance of the turbine rotor 17, which is rotatably supported in a housing section 12, which is elastically supported on a carrier device 1, the turbine rotor 17 is accelerated to a first angular velocity by application of a drive fluid supplied at a first pressure and the oscillation, which is induced by imbalance, is measured. By application of a second higher pressure and coupling of housing section 12 and carrier device 1 by a damping element 23, which damps oscillations, the damped oscillation of the housing section 12, which is induced by imbalance, is measured while the turbine rotor 17 rotates at a second, higher angular velocity. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method and apparatus for dynamic unbalance measurement of a turbine rotor that is rotatably supported in a housing part.

With respect to the support device, the housing portion has at least two degrees of freedom in vibration, and the turbine rotor is accelerated to the first angular velocity by being exposed to the driving fluid introduced by the first pressure, and the turbine rotor is Devices are known that are configured to measure the vibration of the housing part induced by unbalance while rotating at a single angular velocity. (For example, Patent Document 1)
In this apparatus, the vibration system is fixed via at least one spring member.

  The present invention includes a support device that has at least one buffer member and can be fixed so as to have at least two degrees of freedom with respect to relative vibration of the housing portion with respect to the support device. Of a turbine rotor fixed to the turbine and rotatably supported by a housing portion having a turbine housing having an introduction flow path formed for introducing a driving fluid and for adding a driving fluid to the turbine rotor. The present invention relates to a method and apparatus for dynamic imbalance measurement.

Conventional methods and devices of this kind are used to measure the unbalance of a turbine rotor for an exhaust gas operated turbocharger, but in order to obtain the highest possible accuracy, the turbine rotor and turbine rotor Only the so-called turbocharger core assembly consisting of the housing part with the bearing is the object of measurement of the unbalance measurement. If the unbalance measuring device lacks essential housing elements, it can be replaced by similar equipment components, such as a turbine housing. As a result, the resonating mass of the mass structure supported by the spring can be kept small, and the influence of the mass on the unbalance measurement can be reduced. Rotor imbalance measurements are made by rotating the turbine rotor at normal operating speeds. Therefore, the turbine wheel of the turbine rotor is arranged inside the turbine housing of the measuring device, and is accelerated to an angular velocity necessary for measurement by being exposed to compressed air as a driving fluid. The turbine housing is stationary and is separated from the turbocharger core assembly and its bearing vibration parts by a sufficiently large gap. Therefore, it is conceivable that part of the compressed air introduced to operate the turbine rotor escapes through these essential gaps, which results in loss of compression energy and generation of noise. .
JP 2007-132928 A

  The present invention seeks to provide an improved method for measuring the unbalance of a turbine rotor of an exhaust gas turbocharger. It is also an object of the present invention to create an improved device for measuring the unbalance of exhaust gas turbochargers.

  The invention according to claim 1 is a method for measuring dynamic imbalance of a turbine rotor rotatably mounted on a housing part, wherein the housing part has at least two degrees of freedom with respect to relative vibration with respect to the support device. Fixing the housing portion to the support device by interposing at least one elastic element, and accelerating the turbine rotor to a first angular velocity by supplying a driving fluid at a first pressure; Measuring the vibration of the housing portion caused by imbalance while the turbine rotor rotates at the first angular velocity, and supplying the driving fluid at a second high pressure higher than the first pressure, thereby providing a turbine rotor Is accelerated to the second high-speed angular velocity, the housing portion and the support device are coupled by the vibration damping member, and the turbine rotor is Measuring the buffered vibration of the housing part caused by unbalance while rotating at an angular velocity, and a method for measuring the dynamic unbalance of a turbine rotor rotatably mounted on the housing part. is there.

The invention according to claim 2 is characterized in that the buffer member is coupled to the housing portion by aerodynamic force based on the pressure of the supplied driving fluid. This is a measurement method.
The method according to the present invention measures the unbalance of the turbine rotor of an exhaust gas turbocharger at the low angular velocity and the high angular velocity corresponding to the operating speed in the same apparatus and in a clamped state. It has the advantage of being possible. As a result, the measurement accuracy is improved. The self-excited vibration that can be caused by the turbine rotor rotating at a high angular velocity in the vibration system of the unbalance measuring device can be effectively avoided by connecting the housing part to the support device by the buffer member. .

Further, the buffer member is effective when it is connected to the housing portion with air corresponding to the pressure of the introduced driving fluid. Still further, according to the present invention, when the buffer member is connected, the gap between the support device and the housing portion is sealed, and in the case of high pressure, the driving fluid is released through the gap. It may be deployed to be used.
According to a third aspect of the present invention, there is provided a device for measuring a dynamic imbalance of a turbine rotor rotatably mounted on a housing portion, wherein the housing portion has at least two degrees of freedom with respect to relative vibration with respect to the support device. A support device for fixing the housing part via at least one elastic element, and an introduction path fixed to the support device for supplying a driving fluid to the turbine rotor. A turbine housing having a predetermined gap therebetween, and provided in the support device, the housing portion and the support device can be connected to each other, a shock absorbing member for buffering vibration, and provided in the support device, An unbalance measuring device comprising: at least one measuring sensor for detecting vibration of the housing part.

The invention according to claim 4 is the unbalance measuring device according to claim 3, wherein the buffer member is connected to the housing portion by aerodynamic force based on the pressure of the driving fluid.
According to a fifth aspect of the present invention, the ring-shaped surface that is connected between the turbine housing and the housing portion and that faces the turbine housing forms a predetermined gap. A ring body formed on the wall surface of the turbine housing facing the ring-shaped surface, and a ring-shaped buffer provided in the ring groove and pressed against the ring-shaped surface by the pressure of the driving fluid The unbalance measuring device according to claim 3 or 4, comprising a member.

  The cushioning member may be configured as a seal, thereby sealing the gap between the turbine housing and the housing part. With this configuration, the ring chamber is closed simultaneously with the connection of the buffer member, so that the introduced driving fluid cannot escape through the ring chamber. Thus, loss of drive fluid and undesirable flow noise are prevented. The ring groove receiving the buffer member is in a state in which the buffer member is spaced apart from the wall surface of the opposing housing part in the ring groove, and the driving fluid that escapes through the gap is at a high pressure. This is effective when it is configured such that it comes out of the ring groove and is airtightly pressed against the wall surface of the housing part. In this manner, the gap is sealed and the generated resonance is damped because the housing part is connected to the turbine housing by a buffer member.

  The unbalance measuring apparatus shown in the partial configuration diagram in FIG. 1 includes a turbine housing 2 that is supported by a support device 1 and has a spiral introduction flow path 3 and a discharge flow path 4. The turbine housing 2 has a ring-shaped front plate 5 on the front end face facing the discharge flow path 4, and supports the turbine wheel by separating the spiral introduction flow path 3 at the front end face. A central opening is formed. Two rod-shaped spring members 6 are fixed to the support device 1, and they are arranged substantially parallel to the central axis of the turbine housing 2 and on the opposite side with respect to the central axis of the turbine housing 2. Yes. Each spring member 6 has one end portion 7 fixed to the support device 1 by a fixing device 8. The other end portion 9 is bolted to a ring-shaped disc 10 that is positioned coaxially to the turbine housing 2 and is positioned with a slight gap from the front end face side of the turbine housing 2. The disk 10 has a ring-shaped clamping device 11. The clamp device 11 is an outer peripheral edge portion of the disk 10 and is disposed on the side opposite to the spring member 6 and has a function of fixing and clamping the housing portion 12. In the illustrated embodiment, the housing portion 12 of the turbocharger core assembly 13 has a flange 14, and the peripheral portion thereof is fixedly clamped by the clamping device 11. In the illustrated clamping position, it is attached to the side of the disk 10. In addition to the housing part 12, the turbocharger core assembly 13 is provided on one side of the housing part 12 and is fixed to the end of the shaft rotatably supported by the housing part 12, and the other A turbine rotor 17 having a compressor wheel 16 provided on the side is included. In the clamped state, the turbine wheel 15 is inside the front plate 5 at the center of the spiral introduction flow path 3, and the end region enters the inside of the fitting opening of the discharge flow path 4. The inner contour of the opening of the front plate 5 and the fitting opening of the discharge channel 4 may cause the turbine wheel 15 to collide with the turbine housing 2 even when the turbocharger core assembly 13 vibrates during unbalance measurement. The dimensions are such that they extend over a sufficiently large distance from the turbine wheel 15. The compressor wheel 16 provided on the other side of the housing portion 12 is covered with a sealed housing or a protective hood for introducing air as a driving fluid used in the measurement process and for protection reasons.

  As clearly shown in FIG. 2, a ring-shaped gap 18 is formed between the front plate 5 of the turbine housing 2 and the ring-shaped disk 10 so that the turbocharger core assembly 13 can freely move. Can vibrate. The gap 18 communicates with the spiral introduction flow path 3 through the opening of the front plate 5 at the radially inner peripheral edge thereof. The gap 18 is open radially outward. When the turbine wheel is exposed to the compressed air introduced as the driving fluid via the spiral introduction flow path 3, the air reaches the gap 18 and escapes outward.

  In order to prevent this, the front plate 5 is formed with a ring groove 19 that opens toward the gap 18 on the side facing the disk 10. The ring groove 19 is formed as a conical outer wall 20 on the outer side in the radial direction, and its diameter increases toward the gap 18. The inner side in the radial direction of the ring groove 19 is an inner wall 21 having a cylindrical section 211 and a conical section 212 following the cylindrical section 211. The diameter of the frustoconical section 212 increases in the direction of the gap 18 and the inclination of the frustoconical section 212 is approximately equal to or greater than the inclination of the outer wall 20. The inner wall 21 is formed with pockets or slits 22 extending inward in the radial direction and opening toward the gap 18 at some peripheral points.

  A ring-shaped buffer member 23 is provided in the ring groove 19. In the illustrated embodiment, the buffer member 23 is an O-ring and is made of a rubber elastic material. However, a buffer member having another shape may be provided instead of the O-ring. The buffer member 23 has a substantially circular cross section, and its diameter may be slightly larger than the depth of the ring groove 19, but is smaller than the distance between the bottom of the ring groove 19 and the disk 10. The inner diameter of the buffer member 23 is substantially equal to the outer diameter of the cylindrical cross section 211 of the inner wall 21. Thus, the buffer member 23 is installed at the bottom of the ring groove 19 by the cross sections 211 and 212 of the inner wall 21 and is maintained in a stationary state having a maximum distance from the disk 10.

  For the unbalance measurement, the turbine rotor 17 of the turbocharger core assembly 13 is operated via the turbine wheel 15, in which the first, compressed air having a lower pressure is passed via the helical introduction channel 3. First introduced. The first, lower pressure is set so that the turbine rotor 17 is rotated at a considerably lower rotational speed. In this case, it is important that the gap 18 be open so that the turbocharger core assembly 13 vibrates without external loads and moments for the purpose of unbalance measurement. Further, in the case of a low first pressure, the air flowing through the gap 18 passes between the ring groove 19 and the buffer member 23, so that it does not cause a significant pressure drop. Is also guaranteed. The buffer member 23 therefore remains in the rest position as described by the solid line in FIG. 2 and is pulled back into the ring groove 19 during this low-speed measuring step.

  For the measurement of unbalance at high speeds, the pressure of the compressed air introduced is increased to a second, higher pressure to accelerate the turbine wheel 15 to high speeds and accordingly in the gap 18. The air flow speed increases, and at the same time, the pressure drop at the buffer member 23 increases. As a result, the buffer member 23 starts moving from its stationary state, extends, and slides along the outer wall 20 in the direction of the disk 10 until it hits the disk 10. Then, the buffer member 23 closes the gap 18 at the position indicated by the dotted line in FIG. That is, the high pressure is transmitted to the buffer member 23 in the introduction flow path 3, and the buffer member 23 is held at the position indicated by the dotted line in FIG. Therefore, the buffer member 23 closes the gap 18 and thereby acts to buffer the vibration generated when rotating at a high speed. The generation of self-excited vibrations is thereby avoided and the amplitude of the vibrations is reduced to a preferred level. Closing the gap 18 further has the effect of preventing the introduced air from escaping through the gap 18, thereby avoiding high air losses and disturbing flow noise.

When the pressure in the introduction flow path 3 is reduced again to a low value, the movement of the buffer member 23 caused by the elongation overcomes the reduced pressure and is guided by the conical section 212 of the inner wall 21 while the original pressure is reduced. Return to position.
The device described is characterized by a particularly simple structure and a reliable method of operation. However, within the scope of the invention, it is also possible to take the form of another cushioning member, and the coupling of the cushioning member with a part that is prone to vibrations of the device also functions by a pneumatic piston or a diaphragm. be able to.

1 is a partial cross-sectional view of an unbalance measuring device in which a turbocharger core assembly according to the present invention is deployed. FIG. FIG. 2 is an enlarged view of a portion X in FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Support apparatus 2 Turbine housing 3 Introduction flow path 4 Discharge flow path 5 Front plate 6 Spring member 8 Fixing apparatus 10 Ring-shaped disk 11 Clamp apparatus 12 Housing part 13 Turbocharger core assembly 14 Flange 15 Turbine wheel 16 Compressor wheel 17 Turbine Rotor 18 Ring-shaped gap 19 Ring groove 23 Buffer member

Claims (5)

A method for measuring dynamic imbalance of a turbine rotor rotatably mounted on a housing part,
Securing the housing portion to the support device by interposing at least one elastic element such that the housing portion has at least two degrees of freedom relative to vibration relative to the support device;
Accelerating the turbine rotor to a first angular velocity by supplying a driving fluid at a first pressure and measuring vibration of the housing portion caused by imbalance while the turbine rotor rotates at the first angular velocity; ,
By supplying the driving fluid at a second high pressure higher than the first pressure, the turbine rotor is accelerated to the second high-speed angular velocity, and the housing portion and the support device are coupled by the vibration damping member. Measuring the buffered vibration of the housing portion caused by unbalance while rotating at a second high angular velocity;
A method for measuring a dynamic imbalance of a turbine rotor rotatably mounted on a housing portion.   The method of measuring dynamic imbalance of a turbine rotor according to claim 1, wherein the buffer member is connected to the housing portion by aerodynamic force based on the pressure of the supplied driving fluid. An apparatus for measuring the dynamic imbalance of a turbine rotor rotatably mounted on a housing part,
A support device for fixing the housing part via at least one elastic element such that the housing part has at least two degrees of freedom for relative vibrations relative to the support device;
A turbine housing fixed to the support device, having an introduction path for supplying a driving fluid and supplying the fluid to the turbine rotor, and having a predetermined gap with the housing portion;
A buffer member provided in the support device, capable of coupling the housing part and the support device to each other, and buffering vibration;
At least one measurement sensor provided in the support device for detecting vibration of the housing part;
The unbalance measuring device characterized by including.   The unbalance measuring apparatus according to claim 3, wherein the buffer member is connected to the housing portion by an aerodynamic force based on a pressure of the driving fluid. A ring body connected to an end portion which is bent by elasticity of at least one elastic element, provided between the turbine housing and the housing portion, and a ring-shaped surface facing the turbine housing forming a predetermined gap;
A ring groove formed in the wall surface of the turbine housing facing the ring-shaped surface;
A ring-shaped cushioning member provided in the ring groove and capable of being pressed against the ring-shaped surface by the pressure of the driving fluid;
The unbalance measuring apparatus of Claim 3 or 4 containing these.

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