JP5589889B2 - Turbo machine - Google Patents

Description

  The present invention relates to a turbomachine.

Turbomachines such as a turbo compressor and a supercharger include an impeller that is driven to rotate by transmitting rotational power from a shaft.
In such a turbo machine, for example, as shown in Patent Literature 1 and Patent Literature 2, a male screw and a female screw are formed on the impeller and the shaft, and the impeller and the shaft are screwed together. It is concluded.

Japanese Utility Model Publication No. 5-52356 Japanese Utility Model Publication No. 5-57450 Japanese Patent No. 4089802

However, as shown in Patent Document 1 and Patent Document 2, in the configuration in which the male screw and the female screw are formed on the impeller and the shaft, the impeller is rotated with respect to the shaft when the impeller and the shaft are fastened. Must be moved.
That is, when the impeller is attached to the shaft, it is necessary to gradually bring it closer to the shaft while rotating the impeller.
For this reason, the amount of movement of the impeller when the impeller is attached to the shaft is far greater than when the impeller is attached to the shaft without rotating. Therefore, in the methods of Patent Document 1 and Patent Document 2, the amount of work required when the impeller and the shaft are fastened increases.

In order to prevent the impeller and the shaft from shifting in the rotational direction, it is desirable that a sufficient frictional force exists between the impeller and the shaft. For this purpose, it is preferable to push the impeller further toward the shaft side after the impeller comes into contact with the seating surface and elastically deform the impeller.
However, after the impeller comes into contact with the seating surface, a frictional force acts between the impeller and the seating surface, so that the frictional resistance increases, and the work for pushing the impeller toward the shaft increases.

On the other hand, Patent Document 3 discloses a configuration in which a tension bolt is used to firmly fasten the impeller and the shaft almost without causing the impeller to be rotationally moved with respect to the shaft.
However, when the impeller and the shaft are fastened using a tension bolt, a complicated and large device such as a hydraulic tensioner is separately required.

  The present invention has been made in view of the above-described problems. In a turbomachine including an impeller to be fastened and a shaft, the impeller is fastened to the shaft without requiring a complicated and large device. The purpose is to reduce the amount of work.

  The present invention adopts the following configuration as means for solving the above-described problems.

  A first invention is a turbomachine including an impeller that is rotationally driven and a shaft that transmits rotational power to the impeller, wherein one end side is an impeller screwing region that is screwed to the impeller, and the other end side is the above An opening / closing screw which is a shaft screwing region screwed to the shaft, and in which the turning direction of the screw thread formed in the impeller screwing region is opposite to the turning direction of the screw screw formed in the shaft screwing region And the impeller and the shaft are fastened by the open / close screw.

  According to a second invention, in the first invention, the open / close screw is formed of a material having a higher thermal conductivity than the impeller.

  A third invention adopts a configuration in which, in the second invention, when the impeller is formed of a titanium alloy, the open / close screw is formed of a steel material.

  According to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, a configuration is provided in which rotation suppression means for suppressing rotational movement of the impeller with respect to the shaft is provided.

  According to a fifth aspect of the present invention, in the fourth aspect, the rotation restraining means includes a fitting hole provided at a position deviating from the rotation axis of the impeller and the shaft, the rotation axis direction of the impeller being a longitudinal direction. A configuration is adopted in which the pin member is fitted into a fitting hole provided at a position deviated from the rotation axis.

  A sixth invention adopts a configuration in which, in the fifth invention, a plurality of the pin members are evenly arranged around the rotation shaft of the impeller.

  According to a seventh invention, in the fourth invention, the rotation inhibiting means is configured such that the outer shape of the impeller viewed from the rotation axis direction deviates from the shape of the rotating body, and the rotation shaft direction in the rotation axis direction relative to the impeller or the shaft. A configuration is adopted in which a fitting protrusion provided so as to protrude and a fitting hole provided to the impeller or the shaft where the fitting protrusion is not provided and into which the fitting protrusion is fitted are adopted.

  In an eighth aspect based on the seventh aspect, the fitting projection has a shape with the rotational axis as the center of gravity.

  According to a ninth invention, in any one of the first to eighth inventions, a configuration is provided in which a lock bolt that comes into contact with the opening / closing screw from the direction of the rotation axis of the impeller is provided.

  According to a tenth aspect of the present invention, in any one of the first to ninth aspects, the turning direction of the screw thread formed in the impeller screwing region is different from the opening / closing screw by a reaction force when the impeller is rotationally driven. A configuration in which the fastening force with the impeller is set to be increased is adopted.

  According to an eleventh aspect, in any one of the first to tenth aspects, a fitting hole or a fitting protrusion capable of fitting a jig for rotating the opening / closing screw is provided on an end surface of the opening / closing screw on the impeller side. A configuration is adopted in which the impeller is provided with an exposure hole for exposing the fitting hole or the fitting protrusion.

  In a twelfth aspect based on the eleventh aspect, the fitting hole or the fitting projection into which the jig for rotating the opening / closing screw can be fitted has a shape with the rotation shaft of the impeller as a center of gravity. The configuration is adopted.

In the present invention, the impeller and the shaft are fastened by an open / close screw in which the turning direction of the screw thread formed on the impeller side and the turning direction of the screw thread formed on the shaft side are opposite to each other.
According to the present invention, the impeller and the shaft can be linearly moved in the axial direction without rotating the impeller with respect to the shaft by rotating the opening / closing screw. That is, according to the present invention, the amount of movement of the impeller can be reduced compared to the case where the impeller and the shaft are fastened while the impeller is rotationally moved with respect to the shaft, and the amount of work at the time of fastening is reduced. be able to.
Furthermore, according to the present invention, in order to secure a frictional force between the shaft and the impeller, the impeller and the shaft can be moved without rotating the impeller relative to the shaft even when the impeller is pushed into the shaft and elastically deformed. It can be linearly moved in the axial direction. That is, according to the present invention, the frictional resistance can be reduced as compared with the case where the impeller and the shaft are fastened while the impeller is rotationally moved with respect to the shaft, and the amount of work during fastening can be reduced. it can.

  In the present invention, since the impeller and the shaft can be fastened without applying a large tension to the opening / closing screw, a complicated and large device such as a hydraulic tensioner is not required separately.

  Therefore, according to the present invention, in a turbo machine including an impeller to be fastened and a shaft, it is possible to reduce the amount of work when fastening the impeller to the shaft without requiring a complicated and large device. It becomes.

It is sectional drawing which shows schematic structure of the turbo compressor in 1st Embodiment of this invention. It is a schematic diagram for demonstrating the fastening operation | work of the compressor impeller with which a turbo compressor in 1st Embodiment of this invention is provided, and a shaft. It is a schematic block diagram of the turbo compressor in 2nd Embodiment of this invention. It is a schematic block diagram of the turbo compressor in 3rd Embodiment of this invention. It is sectional drawing which shows schematic structure of the turbo compressor in 4th Embodiment of this invention. It is sectional drawing which shows the modification of the turbo compressor in 1st Embodiment of this invention.

Hereinafter, an embodiment of a turbomachine according to the present invention will be described with reference to the drawings. In the following drawings, the scale of each member is appropriately changed in order to make each member a recognizable size.
Further, in the following description, a turbo compressor will be described as an example of the turbo machine of the present invention. However, the turbo machine of the present invention is not limited to the turbo compressor, and an impeller such as a supercharger. The present invention can be applied to all turbo machines including a shaft.

(First embodiment)
FIG. 1 is a cross-sectional view showing a schematic configuration of a turbo compressor S1 of the present embodiment.
The turbo compressor S1 compresses a gas such as air and discharges it as compressed gas. As shown in FIG. 1, the turbo compressor S1 includes a compressor 1, a shaft 2, an opening / closing screw 3, and a drive unit 4. Yes.

  The compressor 1 compresses gas by being driven, and includes a compressor impeller 1a (corresponding to the impeller of the present invention) and a compressor housing 1b.

The compressor impeller 1a is a radial impeller that accelerates the gas sucked from the direction of the rotation axis L and discharges it in the radial direction by applying kinetic energy to the gas.
As shown in FIG. 1, the compressor impeller 1a includes a base portion 1c fastened to the shaft 2 and a plurality of blades 1d arranged on the surface of the base portion 1c at equal intervals in the rotation direction. .

In addition, the base portion 1c is provided with a fitting hole 1e that is opened toward the drive unit 4 side and into which the fitting protrusion 2a included in the shaft 2 is fitted.
Further, as shown in FIG. 1, a housing space for the opening / closing screw 3 is provided in the base portion 1c so as to communicate with the fitting hole 1e. A screw thread is formed on the inner wall surface of the housing space, and one end side of the opening / closing screw 3 is configured to be a female screw that can be screwed together.
Further, the base portion 1c is provided with an exposure hole 1f that exposes one end surface of the opening / closing screw 3 from the tip of the compressor impeller 1a. In addition, the said exposure hole 1f has a diameter which can insert the jig 10 (refer FIG. 2) which rotates the opening-and-closing screw 3 mentioned later, and is provided in the filament.
As shown in FIG. 1, the fitting hole 1 e and the exposure hole 1 f are arranged so as to overlap the rotation shaft L of the compressor impeller 1 a with the accommodation space for the opening / closing screw 3 interposed therebetween.

  And such a compressor impeller 1a is formed with a titanium alloy, an aluminum alloy, or stainless steel, for example according to the gas to compress.

The compressor housing 1b forms the outer shape of the compressor 1 and has a gas flow path therein. The compressor housing 1b accommodates the compressor impeller 1a.
As shown in FIG. 1, the compressor housing 1b includes a suction opening 1g for sucking gas, a diffuser 1h for decelerating and compressing the gas accelerated by the compressor impeller 1a, and a scroll flow serving as a compressed gas flow path. A path 1i and a discharge opening (not shown) through which compressed gas is discharged are provided.

The shaft 2 transmits the power generated by the drive unit 4 to the compressor impeller 1 a as rotational power, and is connected to the drive unit 4.
One end of the shaft 2 is provided with a fitting projection 2a for fitting into a fitting hole 1e provided in the base portion 1c of the compressor impeller 1a, and the fitting projection 2a is fitted into the fitting hole 1e. By combining, the compressor impeller 1a and the shaft 2 are positioned in the radial direction.
As shown in FIG. 1, the fitting protrusion 2 a is provided with a female screw to which the other end of the opening / closing screw 3 can be screwed.
Such a shaft 2 is formed of, for example, a steel material (for example, a steel material containing chromium and molybdenum).

The open / close screw 3 fastens the compressor impeller 1 a and the shaft 2. One end of the open / close screw 3 is an impeller screwing region 3 a that is screwed to the compressor impeller 1 a, and the other end is a shaft screwing region 3 b that is screwed to the shaft 2.
In the open / close screw 3, the turning direction of the thread formed in the impeller screwing region 3a is opposite to the turning direction of the screw formed in the shaft screwing region 3b.
For this reason, when the opening / closing screw 3 is rotated in one direction, the compressor impeller 1a and the shaft 2 approach each other along the rotation axis L, and when the opening / closing screw 3 is reversed, the compressor impeller 1a and the shaft 2 move to the rotation axis L. Will leave along.
The turning direction of the thread formed in the impeller screwing region 3a is set to a direction in which the fastening force between the opening / closing screw 3 and the compressor impeller 1a is increased by a reaction force when the compressor impeller 1a is rotationally driven. .

Further, a fitting hole 3c for fitting a jig 10 for rotating the opening / closing screw 3 is provided on one end surface of the opening / closing screw 3 (surface on the compressor impeller 1a side). The fitting hole 3c is set in a shape (for example, a hexagon) having the rotation axis L as the center of gravity when viewed from the rotation axis L direction. Thus, the shape of the fitting hole 3c becomes a shape with the rotation axis L as the center of gravity, so that the weight distribution around the rotation axis L can be kept uniform when the compressor impeller 1a is driven to rotate, The compressor impeller 1a can be stably rotated.
Note that one end surface of the open / close screw 3 is exposed through the exposure hole 1f provided in the base portion 1c of the compressor impeller 1a as described above. For this reason, the fitting hole 3c formed in the one end surface of the opening-and-closing screw 3 is exposed from the exposure hole 1f.

The open / close screw 3 is preferably made of a material having a higher thermal conductivity than the compressor impeller 1a on condition that the rigidity necessary for fastening the compressor impeller 1a and the shaft 2 can be secured.
Specifically, for example, when the compressor impeller 1a is formed of a titanium alloy, it is conceivable to form the open / close screw 3 of a steel material.
Thus, by forming the open / close screw 3 with a material having a higher thermal conductivity than the compressor impeller 1a, heat transfer from the compressor impeller 1a, which has been heated by gas compression, to the shaft 2 side can be promoted. Heat transfer to the lubricating oil cooled by a cooling mechanism (not shown) can be performed quickly.
Further, when the open / close screw 3 is formed of a steel material and the compressor impeller 1a is formed of a titanium alloy, the open / close screw 3 has a thermal expansion larger than that of the compressor impeller 1a. For this reason, there is a possibility that the compressor impeller 1a and the shaft 2 are separated from each other when the fastening portion is at a high temperature. Expansion can be reduced and it can control that compressor impeller 1a and shaft 2 leave. For this reason, it can suppress that the fastening force of the compressor impeller 1a and the opening-and-closing screw 3 loosens, for example.
In the present embodiment, the open / close screw 3 and the compressor impeller 1a are screwed together, and the open / close screw 3 and the shaft 2 are screwed together. For this reason, the contact area between the opening / closing screw 3 and the compressor impeller and the contact area between the opening / closing screw 3 and the shaft 2 is increased, the heat transfer area is increased, and the above-described heat transfer can be further promoted.

  The drive unit 4 generates power for rotationally driving the compressor impeller 1a and transmits the power to the shaft 2, and includes, for example, a motor and gears.

  In assembling the turbo compressor S1 of this embodiment having such a configuration, when the compressor impeller 1a and the shaft are fastened, first, the impeller screwing region 3a of the opening / closing screw 3 is slightly provided in the compressor impeller 1a. The shaft screwing region 3b is slightly screwed to the female screw provided on the shaft 2. Alternatively, the shaft screwing region 3b is first screwed into the female screw provided on the shaft 2 and the impeller screwing region 3a is screwed into the female screw provided on the compressor impeller 1a.

Subsequently, as shown in FIG. 2, the jig 10 (hexagon wrench) is inserted into the exposure hole 1f provided in the base portion 1c of the compressor impeller 1a, and the fitting hole 3c in which the tip of the jig 10 is exposed from the exposure hole 1f. To fit. Then, the open / close screw 3 is rotated by rotating the jig 10.
As a result, the compressor impeller 1a moves linearly along the rotation axis L without rotating relative to the shaft 2. Then, the compressor impeller 1a and the shaft 2 are fastened by rotating the open / close screw 3 until the fitting protrusion 2a is fitted in the fitting hole 1e and the compressor impeller 1a and the shaft 2 are brought into close contact with each other.

In the turbo compressor S1 of the present embodiment as described above, the opening / closing screw in which the turning direction of the thread formed on the compressor impeller 1a side and the turning direction of the thread formed on the shaft 2 side are opposite to each other. 3, the compressor impeller 1a and the shaft 2 are fastened.
Therefore, by rotating the open / close screw 3, the compressor impeller 1a and the shaft 2 can be linearly moved in the direction of the rotation axis L without causing the compressor impeller 1a to rotate relative to the shaft 2. That is, according to the turbo compressor S1 of the present embodiment, the amount of movement of the compressor impeller 1a is reduced as compared with the case where the compressor impeller 1a and the shaft 2 are fastened while the compressor impeller 1a is rotationally moved with respect to the shaft 2. It is possible to reduce the amount of work at the time of fastening.
Further, in the turbo compressor S1 of the present embodiment, the compressor impeller 1a and the shaft 2 can be fastened without applying a large tension to the opening / closing screw 3, so that a complicated and large device such as a hydraulic tensioner is separately provided. do not need.
Therefore, according to the turbo compressor S1 of the present embodiment, it is possible to reduce the amount of work when the compressor impeller 1a is fastened to the shaft 2 without separately requiring a complicated and large device.

In the turbo compressor S1 of the present embodiment, the turning direction of the thread formed in the impeller screwing region 3a is such that the opening / closing screw 3 and the compressor impeller 1a are driven by the reaction force when the compressor impeller 1a is driven to rotate. Is set in the direction of increasing the fastening force.
For this reason, according to turbo compressor S1 of this embodiment, it can suppress that the fastening force of compressor impeller 1a and opening-and-closing screw 3 loosens during operation.

Further, in the turbo compressor S1 of the present embodiment, a fitting hole 3c in which a jig 10 for rotating the opening / closing screw 3 can be fitted is provided on the end surface of the opening / closing screw 3 on the compressor impeller 1a side. An exposure hole 1f that exposes the joint hole 3c is provided.
For this reason, the open / close screw 3 can be easily rotated by inserting the jig 10 through the exposure hole 1f.

  Further, in the turbo compressor S1 of the present embodiment, the compressor impeller 1a and the shaft 2 are fastened by the opening / closing screw 3, so that the shaft 2 is connected to the compressor impeller like a conventional turbo compressor in order to fix the compressor impeller 1a. There is no need to extend to the tip of la. As a result, the shaft 2 is shortened and the rigidity of the shaft 2 can be improved.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In the description of the second embodiment, the description of the same parts as in the first embodiment will be omitted or simplified.

3A and 3B are diagrams illustrating a schematic configuration of the turbo compressor S2 of the present embodiment, in which FIG. 3A is a cross-sectional view, and FIG. 3B is a view as viewed from the direction of the rotation axis L of the shaft 2.
As shown in these drawings, the turbo compressor S2 of the present embodiment has a rotation direction of the rotation axis L and a rotation direction of the shaft 2 and a fitting hole provided at a position away from the rotation axis L of the compressor impeller 1a. A pin member 5 is provided to be fitted into a fitting hole provided at a position off the axis L.

The pin member 5 is for suppressing the rotational movement of the compressor impeller 1a with respect to the shaft 2, and functions as the rotation suppressing means of the present invention.
And in the turbo compressor S2 of this embodiment, as shown in FIG.3 (b), the pin member 5 is uniformly arrange | positioned centering | focusing on the rotating shaft L of the compressor impeller 1a.

According to the turbo compressor S2 of the present embodiment having such a configuration, when the compressor impeller 1a is attached to the shaft 2 by the pin member 5, the compressor impeller 1a can be prevented from rotating and stably. The compressor impeller 1a and the shaft 2 can be fastened.
Further, according to the turbo compressor S2 of the present embodiment having such a configuration, the pin member 5 functions as a reinforcing material at the joint portion between the compressor impeller 1a and the shaft 2. For this reason, the intensity | strength of the junction location of the compressor impeller 1a and the shaft 2 can be improved.

When the compressor impeller 1a and the shaft 2 are fastened, the pin member 5 is fitted to either the compressor impeller 1a or the shaft 2, and the compressor impeller 1a and the shaft 2 are rotated by the rotation of the opening / closing screw 3. Are brought close to each other and fitted to the other.
For this reason, when the compressor impeller 1a and the shaft 2 are fastened, the pin member 5 cannot be arranged by a conventional fastening method in which the compressor impeller 1a is rotationally moved with respect to the shaft 2.
That is, the turbo compressor S2 of the present embodiment cannot improve the strength of the joint portion between the compressor impeller 1a and the shaft 2, which cannot be realized by a turbo compressor using a conventional fastening method in which the compressor impeller 1a is rotationally moved with respect to the shaft 2. Is realized.

Further, in the turbo compressor S2 of the present embodiment, a plurality of pin members 5 are evenly arranged around the rotation axis L of the compressor impeller 1a.
For this reason, when the compressor impeller 1a is rotationally driven, the weight distribution around the rotation axis L can be kept uniform, and the compressor impeller 1a can be stably rotated.

(Third embodiment)
Next, a third embodiment of the present invention will be described. In the description of the third embodiment, the description of the same parts as those of the first embodiment will be omitted or simplified.

4A and 4B are diagrams illustrating a schematic configuration of the turbo compressor S3 of the present embodiment, in which FIG. 4A is a cross-sectional view, and FIG. 4B is a view as viewed from the direction of the rotation axis L of the shaft 2.
As shown in these drawings, the turbo compressor S2 of the present embodiment has a substantially triangular shape (a shape deviating from the shape of the rotating body) whose shape seen from the direction of the rotation axis L of the compressor impeller 1a is rounded at the apex. In addition, a fitting projection 7 having the center of rotation L as the center of gravity and a fitting hole 6 into which the fitting projection 7 is fitted are provided.

  Such a fitting protrusion 7 and the fitting hole 6 suppress the rotational movement of the compressor impeller 1a with respect to the shaft 2 by fitting, and function as the rotation suppressing means of the present invention.

In the turbo compressor S3 of the present embodiment, the fitting protrusion 7 is provided on the shaft 2, and the fitting hole 6 is provided on the compressor impeller 1a.
However, conversely, a configuration in which the fitting protrusion 7 is provided in the compressor impeller 1a and the fitting hole 6 is provided in the shaft 2 may be employed.

  According to the turbo compressor S3 of the present embodiment having such a configuration, the compressor impeller 1a is prevented from rotating when the compressor impeller 1a is attached to the shaft 2 by the fitting protrusion 7 and the fitting hole 6. The compressor impeller 1a and the shaft 2 can be fastened stably.

Further, in the turbo compressor S2 of the present embodiment, the fitting protrusion 7 has a shape with the rotation axis L as the center of gravity.
For this reason, when the compressor impeller 1a is rotationally driven, the weight distribution around the rotation axis L can be kept uniform, and the compressor impeller 1a can be stably rotated.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described. In the description of the fourth embodiment, the description of the same parts as those of the first embodiment will be omitted or simplified.

FIG. 5 is a cross-sectional view showing a schematic configuration of the turbo compressor S4 of the present embodiment.
As shown in this figure, the turbo compressor S4 of the present embodiment includes a lock bolt 8 that comes into contact with the opening / closing screw 3 from the direction of the rotation axis L of the compressor impeller 1a (left side in the drawing). In addition, the turning direction of the thread formed in the impeller screwing region 3a of the open / close screw 3 and the thread provided in the lock bolt 8 is the same direction.

  The lock bolt 8 is provided with a tool hole (for example, a hexagon) that penetrates in the direction of the rotation axis L and is used when the lock bolt 8 is tightened or loosened. The inscribed circle of the tool hole is set to be larger than the circumscribed circle of the jig 10 fitted in the fitting hole 3c of the opening / closing screw 3. For this reason, the jig 10 can be fitted into the opening / closing screw 3 through the lock bolt 8.

  According to the turbo compressor S4 of the present embodiment having such a configuration, even if the compressor impeller 1a tries to rotate and move in the direction in which the fastening force is loosened, the open / close screw 3 is rotated by the lock bolt 8 to the rotating shaft. Displacement in the L direction can be suppressed, and as a result, the compressor impeller 1a can be prevented from rotating in the direction in which the fastening force is loosened.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the said embodiment. Various shapes, combinations, and the like of the constituent members shown in the above-described embodiments are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

For example, in the above-described embodiment, the pitch of the threads formed in the impeller screwing area 3a can be different from the pitch of the threads formed in the shaft screwing area 3b.
By adopting such a configuration, the amount of movement of the compressor impeller 1a and the amount of movement of the shaft 2 per unit rotation of the opening / closing screw 3 change. Conversely, the amount of rotation of the opening / closing screw 3 with respect to the unit movement amount of the compressor impeller 1a and the shaft 2 is different.
As a result, when the turbo compressor is operating, it can be expected that the opening / closing screw 3 is prevented from rotating when the compressor impeller 1a and the shaft 2 try to move in the direction of the rotation axis L. Therefore, loosening of the fastening force between the compressor impeller 1a and the open / close screw 3 can be suppressed.

For example, in the said embodiment, the fitting protrusion 2a is provided in the shaft 2, and the fitting hole 1e is provided in the compressor impeller 1a.
However, as shown in FIG. 7, it is also possible to adopt a configuration in which a fitting protrusion is provided on the compressor impeller 1 a and a fitting hole is provided on the shaft 2.
By adopting such a configuration, as shown in FIG. 6, the opening / closing screw 3 is arranged at a position where it is largely inserted into the shaft 2. Therefore, the open / close screw 3 can be released from the root region of the maximum diameter portion where the load is great due to the highest stress applied to the compressor impeller 1a, and the load acting on the open / close screw 3 can be reduced. And since the opening / closing screw 3 is removed from the maximum stress portion of the compressor impeller 1a, a higher axial force can be applied to the compressor impeller 1a, and the fastening force between the compressor impeller 1a and the shaft 2 can be increased.

  In the above embodiment, in order to suppress the loosening of the fastening force due to thermal expansion during operation, an axial force that can alleviate the loosening of the fastening force due to thermal expansion may be applied to the open / close screw 3. good.

Moreover, in the said embodiment, as shown in FIG. 2, the structure provided with the fitting hole 3a in which the opening-and-closing screw 3 is fitted with the jig 10 was employ | adopted.
However, the present invention is not limited to this, and it is also possible to adopt a configuration in which the open / close screw 3 is provided with a fitting protrusion into which a jig can be fitted instead of the fitting hole 3a.

Moreover, in the said embodiment, the turbo compressor with which one shaft and the one compressor impeller 1a was fastened to the end of the said shaft was demonstrated.
However, the present invention is not limited to this, a turbo compressor in which a compressor impeller 1a is fastened to both ends of one shaft, a turbo compressor having a plurality of shafts and a compressor impeller provided on each shaft. It is also possible to apply to a turbo compressor provided with other equipment such as a cooler for cooling the compressed gas.

  S1 to S4: turbo compressor (turbo machine), 1 ... compressor, 1a ... compressor impeller (impeller), 1b ... compressor housing, 1c ... base, 1d ... blade, 1e ... fitting hole 1f ... exposed hole, 1g ... suction opening, 1h ... diffuser, 1i ... scroll channel, 2 ... shaft, 2a ... fitting projection, 3 ... opening / closing screw, 3a ... impeller screwing area 3b: Shaft screwing region, 3c: fitting hole, 4 ... drive unit, 5 ... pin member (rotation inhibiting means), 6 ... fitting projection (rotation inhibiting means), 7 ... fitting Hole (rotation suppression means), 8 ... Lock bolt

Claims (12)

A turbomachine comprising an impeller that is rotationally driven and a shaft that transmits rotational power to the impeller,
One end side is an impeller screwing region to be screwed to the impeller, and the other end side is a shaft screwing region to be screwed to the shaft, and a turning direction of a thread formed in the impeller screwing region and the shaft Having an opening and closing screw in which the turning direction of the thread formed in the screwing region is opposite;
The turbomachine characterized in that the impeller and the shaft are fastened by the open / close screw.   The turbomachine according to claim 1, wherein the open / close screw is made of a material having a higher thermal conductivity than the impeller.   The turbomachine according to claim 2, wherein when the impeller is formed of a titanium alloy, the opening / closing screw is formed of a steel material.   The turbomachine according to any one of claims 1 to 3, further comprising a rotation suppression unit that suppresses the rotational movement of the impeller with respect to the shaft.   The rotation suppression means has a fitting hole provided at a position deviating from the rotation axis of the impeller and a fitting hole provided at a position deviating from the rotation axis of the shaft, the rotation axis direction of the impeller being a longitudinal direction. The turbomachine according to claim 4, wherein the turbomachine is a pin member fitted to the pin.   The turbo machine according to claim 5, wherein a plurality of the pin members are equally arranged around a rotation axis of the impeller. The rotation inhibiting means is
A fitting projection provided to protrude from the impeller or the shaft in the direction of the rotation axis while the outer shape viewed from the direction of the rotation axis of the impeller deviates from the shape of the rotating body
The turbomachine according to claim 4, further comprising: a fitting hole provided on the impeller or the shaft on which the fitting protrusion is not provided and into which the fitting protrusion is fitted.   The turbo machine according to claim 7, wherein the fitting protrusion has a shape with the rotation axis as a center of gravity.   The turbomachine according to claim 1, further comprising a lock bolt that comes into contact with the open / close screw from a rotation axis direction of the impeller.   The turning direction of the thread formed in the impeller screwing region is set to a direction in which the fastening force between the open / close screw and the impeller is increased by a reaction force when the impeller is rotationally driven. The turbomachine according to claim 1.   A fitting hole or a fitting projection capable of fitting a jig for rotating the opening and closing screw is provided on an end surface of the opening and closing screw on the impeller side, and an exposure hole exposing the fitting hole or the fitting projection is provided on the impeller. The turbomachine according to claim 1, wherein the turbomachine is provided.   12. The turbomachine according to claim 11, wherein the fitting hole or the fitting projection into which the jig for rotating the opening / closing screw can be fitted has a shape with the rotation axis of the impeller as a center of gravity.

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