KR20160060752A - Turbo engine with torsional coupling integrated to at least one driving or driven shaft driving - Google Patents

Abstract

The turbo engine of the present invention comprises a drive shaft (3); And a driven shaft (8) driven by the drive shaft and movably coupled to the drive shaft by torsional coupling. The torsion coupling is incorporated into at least one of the driven shaft and the drive shaft, including the rotatably flexible region (11: 17) in such a manner as to constitute the torsion coupling.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a turbo engine having a torsion coupling incorporated in at least one drive shaft drive device or a driven shaft drive device.

The present invention relates to a turbo engine, such as an integrated motor-driven compressor. However, of course, only by relating to a different type of turbo engine, i.e., a turbo generator, the turbo engine does not depart from the system of the present invention.

The integrated motor-driven compressor group includes an engine, for example, a leakage preventing housing for housing an electric motor, and a compressor group, such as a multi-stage unit, which is supported by a driven shaft and is composed of a rotor of the motor, And one or more wheels with compression blades that are actuated by a drive shaft that is actuated by a drive shaft.

One coupling solution for the drive shaft and the driven shaft is to couple the driven shaft and the drive shaft using a rigid coupling wherein the ends of the line of the shaft of the motor- A bearing is provided to support the intermediate portion of the bearing.

This solution causes problems related to manufacturing problems and rotor dynamics in some cases.

It is therefore proposed to combine the drive shaft and the driven shaft with a flexible coupling to avoid problems with alignment. In this regard, reference can be made to document WO 2004/083644 which describes the layout described above.

Flexible couplings, which are currently in use and are generally membrane-laden, typically increase the axial dimension of the motor-driven compressor group by 35 to 40 cm compared to rigid couplings with flanges. In addition, there is a fragility zone because the flexible coupling can only receive tensile or compressive forces that are confined, for example, only in the axial direction.

However, while the layout described in document WO 2004/083644 functions, the gas supplied to the compressor is completely or partially extracted after the compression stage and is used for cooling the motor. The flow of cooling gas in the motor is formed in the direction of the compressor.

The motor-driven compressor has a single adjacent to the rotor of the compressor, i. E., The opposite side of the coupling. Due to this fact, an axial thrust is generated in the motor, and this axial thrust is absorbed by the coupling before being transmitted to the axially adjacent portion.

Therefore, in order to alleviate this inconvenience, it has been proposed to use a torsional coupling disposed in the hollow shaft of the compressor. This layout is described in document FR 2 969 722. This layout is effective in mitigating the inconvenience associated with using a flexible coupling between the drive shaft and the driven shaft, but this layout complicates the structure of the shaft assembly.

In view of the foregoing discussion, it is an object of the present invention to alleviate the inconvenience associated with layout in accordance with the prior art, and in particular to enable the axial force generated during the implementation of the function of the compression level to be supported in a simple layout will be.

Accordingly, it is an object of the present invention to provide a turbo engine including a drive shaft, and a driven shaft that is driven by the drive shaft and is movably coupled to the drive shaft by a torsion coupling.

Additionally, the torsion coupling is incorporated into at least one of the driven shaft and the drive shaft, including a torsional flexible region to form a torsional coupling.

This may be a group of motor-driven compressors comprising a motor for driving the compressor, and may for example comprise a set of wheels with compression blades mounted on a driven shaft.

The set is mounted in a general housing which is impermeable to gas generated by the motor-driven compressor group.

Since the torsional coupling is incorporated in the drive shaft and / or the driven shaft, the above-mentioned problems that exist in the case where the torsional coupling is assembled to the drive shaft or the driven shaft as described in the above-cited document FR 2 969 722, That is, problems in structure and manufacturing, and problems in the assembly are solved.

Additionally, the shaft incorporating the torsion coupling preferably includes an outer perimeter area that constitutes a means for supporting the function performed by the rotor.

This torsion zone, which is at least present in one of the drive shaft and the driven shaft, is formed, for example, by a cylindrical part, which has a smaller diameter than the rest of the shaft into which the torsion coupling is integrated.

Advantageously, the torsion zone has a length selected in relation to said diameter in such a manner as to impart a torsion capability to the coupling. Due to the presence of this reduced diameter portion, the shaft assembly includes a reduced-size inner shaft through which the drive shaft and the driven shaft are coupled to allow for local deformation of the shaft assembly due to torsion do.

In another embodiment, the torsional cylindrical portion can be mounted on the driven shaft, or on the drive shaft, or on both shafts, i.e. both on the drive shaft and the driven shaft.

The torsional cylindrical portion may be entirely protruding from the shaft into which the coupling is incorporated, or may be partially or wholly located in the interior of the hollow portion in the form of a hollow shaft, such that the hollow shaft It is possible to support one or several functions performed by the rotor. When the torsional cylindrical portion is to be located inside the hollow shaft, the hollow shaft thus exists in a cantilevered manner around the torsional cylindrical portion. This solution may ultimately be realized by reducing the diameter of the assembly or by a throat.

Implementing a partially or completely torsional cylindrical portion in the hollow portion may allow the length of the shaft assembly to be limited, thereby limiting the dimensions, weight and cost of the turbo engine.

This can also have a beneficial effect on the dynamic characteristics of the rotor.

It should be noted that the torsional cylindrical portion (s) can be obtained using various techniques.

One embodiment includes an axial cylindrical neck that is configured to operatively couple another inner shaft to another drive shaft or other driven shaft and one outer shaft within the shaft. For example, the axial cylindrical neck is formed by electroerosion.

Alternatively, such torsion coupling is obtained by reducing the diameter at the driven shaft and / or drive shaft in the manufacturing step (e.g., by forging and machining).

In this case, at least one of the driven shaft and the drive shaft includes, in the torsional coupling region of these shafts, one axial cylindrical neck formed by the inner shaft and one outer shaft assembled around the inner shaft do.

In one embodiment, the outer shaft extends to a connecting region of the drive shaft and the driven shaft.

According to another embodiment, the free end of the shaft, into which the torsion coupling is incorporated with a diameter greater than the diameter of the intermediate portion, forms a coupling region of said inner shaft with another drive shaft or other driven shaft.

Alternatively, it can also be ensured that the free end of the shaft to which the torsion coupling is associated corresponds to another drive shaft or other driven shaft and has a diameter smaller than the diameter of the coupling region coupled to these shafts, A flange is formed to ensure coupling of the shaft or driven shaft.

Other objects, features and advantages of the present invention will become apparent upon reading the following description, which is given by way of non-limiting example only, with reference to the accompanying drawings.

1 is a schematic diagram showing a general structure of a motor-driven compressor group according to the present invention.
Fig. 2 shows a first embodiment of the motor-driven compressor group according to Fig.
3 shows another embodiment of the motor-driven compressor group according to the present invention.
4 shows another embodiment of the compressor group according to the present invention.
Figure 5 presents another embodiment of the torsion zone.

Referring first to Figure 1, a motor-driven compressor according to the present invention, indicated generally by the reference character G, essentially comprises a motor 1 and a compressor group 4, for example, A rotor (3) and a stator (2) having a high rotation speed of 6,000 to 16,000 and being powered by a frequency converter and forming a drive shaft for a motor-driven compressor group, (4) includes a set of wheels mounted on a driven shaft (8), here having three blades (5, 6, and 7) in numerical plane. As can be appreciated, the driven shaft 8 is supported by a radial bearing 9.

This device is mounted on a base (not shown) and is placed in a conventional casing 10 which is impermeable to gas generated by a motor-driven compressor group. The casing 10 includes an inlet (inlet) and an outlet ("outlet") through which the generated gas is drawn into the compressor through the inlet and the compressed gas exits the compressor group 4 And is then transferred through the output section when it exits.

In the illustrated embodiment, the compressor group 4 comprises three wheels with blades mounted on the driven shaft 8. [ It is clear that the compressor group 4 may comprise any number of such wheels with blades, or may comprise wheels of different layouts with blades.

1 and 2, a driven shaft 8 is provided, a shoulder E is provided at the level of the end region of the driven shaft, and the driven shaft is driven by the motor 1, Is bolted to the drive shaft 3 at one end thereof.

In any case, the coupling between the driven shaft and the drive shaft consists of a torsion coupling.

This torsional coupling is obtained by applying a torsion zone, i.e., a zone that is flexible during rotation, in at least one of the driven shaft and the drive shaft.

1 to 4, the torsion coupling comprises an inner shaft 12 which, in the driven shaft 8, allows the driven shaft 8 to be coupled to the drive shaft 3, and a driven shaft (not shown) 8 is obtained by machining the axial cylindrical portion 11 in the driven shaft 8 so as to form an outer shaft 13 which is supported by the radial bearing 9. [ The length of the neck is selected in relation to the diameter of the shaft and the neck is mounted on the shaft using a selected length in such a way as to impart a torsional characteristic to the coupling.

In this way, by mounting the cylindrical neck on the driven shaft 8, the useful diameter of the driven shaft 8, which transmits the actual working force, is locally reduced, and the tolerance of the driven shaft to the torsional deformation and radial deformation , While maintaining significant radial stiffness. The driven shaft, in particular the inner shaft 12, remains particularly resistant to axial forces generated during operation of the wheel with the compression blades 5, 6 and 7.

In the presence of the torsion portion, due to the localized reduction of the useful section of the shaft assembly, during installation of the motor-driven compressor or during operation of the motor-driven compressor, A feature that can be deformed by bending and by elastic twisting can be imparted to the driven shaft 8 in such a way that the displacement, on the one hand, and the other deviation on the other side, can be compensated.

In addition, this flexibility allows the flexural vibration between the drive shaft and the driven shaft to be filtered.

Moreover, the torsion zone allows a gradation of the force to be transmitted to be achieved while the torque transmitted by the motor or the resistance torque generated by the compressor changes abruptly.

Additionally, the abovementioned mounting is greatly simplified because the shaft assembly simply consists of two parts of the shaft, namely the drive shaft and the driven shaft.

It should be noted that, in the embodiment shown in Figs. 1 and 2, the torsional portion is mounted on the driven shaft 8. [ In addition, the driven shaft 8 includes an outer shaft 13 with its end in the rear, relative to the free end of the inner shaft 12, such that the inner shaft 12 is fixed to the drive shaft 3 . In other words, in the present embodiment, the inner shaft 12 has a diameter smaller than the diameter of the end portion formed by the shoulder E.

In addition, as can be seen in FIGS. 1 and 2, in the manufacturing step, for example, the diameter of the driven shaft is reduced by forging and machining of the driven shaft 8, And then to obtain a torsional coupling by implementing a cylindrical neck to form the outer shaft 13.

The torsional coupling obtained by placing the neck on the drive shaft in the embodiment shown in Figs. 1 and 2 can be achieved by placing this neck on the drive shaft or by placing this neck on the two shaft-drive shaft and the driven shaft Of course, be formed.

In another embodiment, as seen in FIG. 3, the outer shaft 13 extends over a substantial portion of the inner shaft 12, which has no shoulders at its ends. Therefore, in the mounting of the inner shaft 12 on the end of the drive shaft 3, a flange (not shown) fixed by being bolted on the free end of the drive shaft 3 and connected to rotate about the inner shaft 12 14). For example, an axial neck can be provided on the inner circumferential surface of the flange 14, which is engaged with a corresponding rib mounted on the free end of the inner shaft 12. [

In this regard, as can be seen in Fig. 3, a flange having a generally conical shape or provided with a shoulder at the end can be used.

As long as the distance between the ends of the shafts can be shortened, that is, the distance between the free end of the outer shaft 13 and the free end associated with the drive shaft 3 can be shortened And this distance is defined by the length of the flange 14.

According to the third embodiment shown in Fig. 4, both the drive shaft 3 and the driven shaft 4 have the axial cylindrical portion 11 and the axial cylindrical portion 11a. The neck 11 is similar to the neck used in the embodiment in Fig.

As with the driven shaft, the axial cylindrical neck 11 forms an inner shaft 12 and an outer shaft 13 extending along a substantial portion of the inner shaft 12, as in the previously described embodiment, Wherein the inner shaft 12 extends from the outer shaft 13 in a protruding manner along a length sufficient to mount the flange 15.

In relation to the drive shaft 3, the axial cylindrical portion 11a forms an inner shaft 16 and an outer shaft 17 extending along a substantial portion of the inner shaft 16 in this shaft 3 , Wherein the inner shaft extends over the length sufficient to mount the flange (15) beyond the free end of the outer shaft (17).

Thus, in the present embodiment, the twist region of the shaft assembly is formed in the drive shaft 3 and in the driven shaft 8. [

In other words, as compared to the previously described embodiment, the shaft assembly includes a long torsion zone.

The embodiment shown in Figs. 3 and 4, in which the mounting of the driven shaft and the drive shaft is carried out by the fitted flange, is carried out in such a way that the torsion zone can be formed in the manufacturing step, .

The implementation of the torsion zone consists in particular of implementing the inner shaft in the driven shaft 8 and the driven shaft 8 is passively coupled to the drive shaft 3 via the inner shaft and the outer shaft 13 Is subsequently assembled to the driven shaft 8 and the driven shaft is guided by the radial bearing 9 in such a manner that the driven shaft forms a cylindrical neck between the two shafts, i.e., the inner shaft and the outer shaft . In other words, and as shown in dashed lines in the figure, the outer shaft is assembled around a region of the shaft whose diameter is reduced.

This assembly can be accomplished using various means. The hollow portion may be formed, for example, in close proximity to the torsion region, for example, by bolting and / or through the diameter of the adjacent portion and / or using a toothed hirth and / Lt; / RTI >

The embodiment shown in Figs. 3 and 4, in which the driven shaft includes an inner shaft 12 and an outer shaft 13, can also be used where the outer shaft can be used for the implementation of the function performed by the rotor Therefore, it is advantageous.

In particular, the support of one or several wheel (s) with bearing support and / or blade (s) may be implemented (see FIG. 3).

It is apparent that the present invention is not limited to the embodiments described above. It is also possible in the variant to arrange the axial cylindrical neck on the drive shaft and on the driven shaft, and the distance between the ends of the shafts in relation to both the drive shaft and the driven shaft, i.e. the distance between the two outer shafts 13 and 17 is equal to one half of the torsional length, that is to say that the length of the inner shaft extending from the outside of the outer shaft is referred to FIG. 2 in relation to both the drive shaft and the driven shaft It is also possible in a variant to ensure that the length of the outer shaft is equal to the length of the outer shaft as in the embodiment described with reference to Fig.

Thus, in the embodiment shown in FIG. 5, the torsional area can be formed by implementing a reduced diameter area in a manner that imparts a torsional characteristic to the coupling during manufacture of the driven shaft. As in the embodiment of the previously described embodiment, the coupling with the drive shaft can be realized in both ways by providing the shoulder E at the end as shown or by using the fitted flange.

The reduced diameter area can also be implemented independently of the rest of the driven shaft and can be assembled to the driven shaft as already pointed out with reference to Figs.

As pointed out earlier, it is clear that alternatively, a reduced diameter region may be formed in the drive shaft or in two shafts, namely the driven shaft and the drive shaft. It should be noted that, as in the embodiment shown in Figs. 1-4, the length of the reduced diameter region can be chosen in relation to the diameter of this region in such a way as to impart a torsional characteristic to the shaft.

For example, for a shaft diameter of the order of 50 mm, the torsion zone may be implemented over a length between 600 and 700 mm.

And, finally, in various embodiments, the axial cylindrical neck formed in the driven shaft and / or in the drive shaft may be formed by electrowetting or by EDM ("Electrical Discharge Machining") It is a process that consists of removing material from one piece using electric discharge.

Claims (15)

1. A turbo engine comprising a drive shaft (3) and a driven shaft (8) operated by a drive shaft, wherein the driven shaft is coupled to the drive shaft by torsional coupling, Wherein a torsion coupling including a rotatably flexible region (11; 17) is incorporated in at least one of a driven shaft and a drive shaft in such a manner as to constitute a torsional coupling. 2. The turbo engine of claim 1, wherein the shaft into which the torsion coupling is integrated further comprises an outer perimeter region, the outer perimeter region constituting support means for the function performed by the rotor. The turbo engine of claim 1 or 2, wherein the flexible region comprises a cylindrical portion having a smaller diameter than the rest of the shaft into which the flexible coupling is integrated. 4. The turbo engine of claim 3, wherein the length of the cylindrical portion is selected in relation to the diameter in such a manner as to impart a torsion characteristic to the coupling. 5. Turbo engine according to claim 3 or 4, characterized in that the cylindrical part (11) is mounted on a driven shaft or on a drive shaft. 5. Turbo engine according to claim 2 or 4, wherein the cylindrical part (11) is mounted on the driven shaft and on the drive shaft. 7. Turbo engine according to any one of claims 3 to 6, wherein the torsional cylindrical portion projects entirely, starting from the shaft into which the torsional coupling is integrated. 7. Turbo engine according to any one of claims 3 to 6, wherein the torsional cylindrical part is located partly or entirely in the hollow part (13). 9. A device according to any one of the preceding claims, wherein at least one of the drive shaft and the driven shaft has an axially cylindrical neck (12) defining the shaft and the inner shaft (12) in its torsional coupling region 11, 11a, the axial cylindrical neck being coupled to another drive shaft or other driven shaft and an outer shaft (13). 10. The turbo engine of claim 9, wherein the axial cylindrical neck is formed by electroerosion. 9. A device according to any one of the preceding claims, wherein at least one of the drive shaft and the driven shaft is defined by an inner shaft in its torsional coupling region and an outer shaft assembled around the inner shaft And comprises an axial cylindrical neck (11, 11a). The turbo-engine according to any one of claims 9 to 11, wherein said outer shaft constitutes said support means for a function performed by a rotor. 12. Turbo engine according to any one of claims 9 to 11, wherein the outer shaft (13) extends by a connecting area of the drive shaft and the driven shaft. 14. A device according to any one of the preceding claims, wherein the free end of the shaft (12) into which the torsion coupling is incorporated has a diameter greater than its middle portion and is coaxial with the other drive shaft or other driven shaft And forming a coupling region of the inner shaft. 14. A device according to any one of the preceding claims wherein the free end of the shaft into which the torsion coupling is incorporated has a diameter smaller than the diameter of the connecting region corresponding to the other drive shaft or other driven shaft to which it is coupled, And the flange (14) ensures coupling of these shafts.

Images