JP2006022645A - Turbo type high speed rotary apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a turbo type high speed rotary apparatus capable of removing a lip seal material constricting a seal mechanism of a gas compression chamber and a motor chamber from a rotary shaft at a time of balance test. <P>SOLUTION: A bearing retaining member 8 for retaining an upper bearing 5 is provided on a housing 1. A seal plate 9 equivalent to a partition wall is mounted thereon and is installed on the housing. A rotary shaft 4 is provided to penetrate through a through hole 9H of the seal plate 9. The lip seal material 10 is attached inside of the through hole 9H of the seal plate 9, and an inner end thereof abuts on an outer circumference surface of the rotary shaft 4 as shown on a figure. A small diameter part 4K of an annular recess part is formed in an upper vicinity of the rotary shaft 4 on which the lip seal material slides. When the rotary shaft 4 displaces and the lip seal material 10 positions at the small diameter part 4K, contact with the rotary shaft 4 is cut off. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a turbo-type high-speed rotating device that can be applied to, for example, a blower as an electric compressor for gas circulation in a gas laser oscillator device.

  For example, in the case of a flow type carbon dioxide gas laser oscillator device, it is compressed while flowing a mixed gas of carbon dioxide gas and other gas and supplied to the laser oscillator to resonate, and a gas circulation circuit is configured in the device. Yes. A turbo-type high-speed rotating device that compresses gas by rotating a turbo blade at high speed and supplies the gas to a laser oscillator is used as a blower as one element in the circuit configuration.

  In this type of turbo high-speed rotating device, a turbo blade is rotatably disposed above a housing, a mechanism for compressing and discharging gas is provided, and a motor for rotating the turbo blade at a high speed is provided below. It is arranged. The rotating body including the rotor of the motor, the turbo blade, the rotating shaft, and the like is supported by a mechanical bearing system and is provided with a lubricating means using oil. Therefore, although oil mist is generated, a method of exhausting with a vacuum pump is employed so that the oil mist is not discharged together with gas compression (see Patent Document 1).

  The specific configuration of the turbo-type high-speed rotating device is as shown in FIG. 6. A turbo blade 7 is rotatably disposed on the inside of the housing 1. A motor 2 for rotational driving is arranged, and both are connected by a rotating shaft 4. The motor 2 is composed of an electrode coil 2K fixed on the housing 1 side and a rotor 2M fixed to the rotary shaft 4 corresponding to the electrode coil 2K. Electric energy is supplied to the electrode coil 2K from the inverter 3. Is supplied.

The rotary shaft 4 is rotatably held with respect to the housing 1 via an upper bearing 5 and a lower bearing 6. A turbo blade 7 is fixed to a mounting shaft 4 </ b> S formed above the rotary shaft 4. Yes. A rotating body including the motor 2, the rotor 2M, and the rotating shaft 4 is held by an upper bearing 5 and a lower bearing 6 that constitute a bearing mechanism. The upper bearing 5 and the lower bearing 6 are disposed in the motor chamber M. When the turbo blade 7 is driven to rotate at high speed by the motor 2, the gas is sucked from the inlet 1K, compressed, and exhausted 1H. More discharged. The gas compression chamber C is formed from the intake port 1K to the exhaust port 1H. The gas from the exhaust port 1H is supplied to a laser oscillator (not shown) through a gas circulation circuit (not shown) as described above.

  As shown in FIG. 6, the rotary shaft 4 has a hollow hole 4H formed on the shaft core. The lower part of the hollow hole 4H has a tapered shape with the inner hole expanding upward, and these lower parts Is immersed in the lubricating oil L. Accordingly, the lubricating oil L entering the lower region of the hollow hole 4H moves upward in the hollow hole 4H under the action of the centrifugal force caused by the rotation of the rotary shaft 4, and this action causes the hollow hole 4H to move upward. 4H demonstrates the pump function. Thus, the lubricating oil L is sequentially sent upward and discharged outward from the injection hole 4T to cool the motor 2 and lubricate the upper bearing 5 and the lower bearing 6. The lubricating oil L that has been lubricated and cooled is again stored in the lower oil tank 1Y, sucked up again, and circulated.

  In this way, the lubricating oil L circulates to lubricate the upper bearing 5 and the lower bearing 6. By this lubrication, especially in the motor chamber M, sprayed oil L (oil mist) exists and floats. It will be. The presence of this oil mist in the motor chamber M improves the lubrication in the upper bearing 5 and the lower bearing 6 and the like, but when this oil mist flows into the gas compression chamber C, it flows into a laser oscillator and the like, and has a laser oscillation function. Reduce.

  Therefore, the housing 1 is provided with a partition wall W at a position above the upper bearing 5, and the gas compression chamber C and the motor chamber M are blocked by the partition wall W. The partition wall W is formed with a through hole 1A having a minimum diameter that allows the rotary shaft 4 to pass through without contact, and a seal portion S that cooperates with the rotary shaft 4 is formed. For example, a labyrinth seal shown in the illustrated example is applied to the seal portion S. In the seal portion S by the labyrinth seal, the gap between the rotating shaft 4 and the through hole 1A is usually set to several tens of microns. However, in the case of this labyrinth seal method, it is necessary to provide a plurality of steps of unevenness on the peripheral surface of the rotating shaft 4 and the inner peripheral surface of the through-hole 1A or any one of these surfaces, which is difficult to process and costly. Has a bulky problem. Further, in the labyrinth seal system, the gap is several tens of microns, and when the rotary shaft 4 is eccentric in this gap, the amount of contact or fusion due to vibration of the rotary shaft 4 or leakage from the seal gap increases. Therefore, it is necessary to improve the processing accuracy and assembly accuracy of the labyrinth seal, and a contact-type sealing method is proposed by using a lip seal material in which the inner periphery is in sliding contact with the outer peripheral surface of the rotary shaft 4 Has been.

The motor chamber M is evacuated to vacuum by an external vacuum pump VP via an exhaust pipe R. This is to prevent the motor chamber M from being filled with the mist of the lubricating oil L and leaking into the gas compression chamber C through a small gap in the seal portion S as described above.
JP 2000-209815 A

In the manufacturing process of such a turbo-type high-speed rotating device, since the rotating part is driven to rotate at a very high speed, the presence of a slight unbalance is not allowed. Therefore, a balance test is performed to ensure the balance of the rotating part (the entire rotating body), and if there is an unbalance, a correction is made to remove it. In the balance test, the rotating body part is tested and measured at high speed. In this case, noise is generated when the lip seal material is in contact with the rotating shaft as described above, and it is impossible to detect minute imbalances. become. This is not a perfect balance.
An object of the present invention is to provide a turbo-type high-speed rotating device that solves such problems.

  In order to solve the above problems, the turbo-type high-speed rotating device provided by the present invention improves the sealing mechanism between the through hole and the rotating shaft in the partition wall between the gas compression chamber and the pump chamber as follows. A through-hole that penetrates the rotation shaft is formed in the partition wall, and a conical lip seal material extending inward from the partition wall is provided between the through-hole and the rotation shaft. The seal material contacts the entire circumferential surface of the rotary shaft after the pump is assembled, and has a sealing function between the rotary shaft and the through hole when the pump is operated. On the other hand, an annular recess is formed in the rotating shaft in the vicinity of the position where the lip seal material contacts the peripheral surface, and means for displacing the rotating shaft in the axial direction with respect to the partition wall is provided. Therefore, the position of the annular recess reaches the lip seal material position due to the displacement of the rotation shaft, and the lip seal material is detached from the peripheral surface of the rotation shaft or the contact allowance is reduced.

The turbo high-speed rotating device provided by the present invention is as described in detail above, and thus has the following effects.
(1) In the balance correction operation in the manufacturing process, the lip seal material can be easily brought into a non-contact state with the rotating shaft, and complete balance correction can be performed.
Provided is a turbo-type high-speed rotating device that is economical and excellent in performance due to the above characteristics.
(2) According to the present invention, it is possible to easily realize a minute gap on the order of several microns, which is a feature of the lip seal material, and to provide a sealing mechanism with a very large pressure loss, thereby reducing gas consumption.
(3) In the case of the embodiment in which the lip seal material is bent into a conical shape, the spring effect can be fully exerted, and therefore the initial sliding torque is appropriately reduced by changing the angle of the cone even if there is a variation in manufacturing. it can.

  According to the present invention, a gas compression chamber in which turbo blades are arranged, a partition wall that partitions the motor chamber in which the turbo blade bearing mechanism and the motor are arranged are provided in a housing, and the rotating shaft passes through the partition wall. A basic structure is such that a through-hole is formed and a lip-shaped sealing mechanism is provided between the through-hole and the rotating shaft. The lip seal material functioning as the lip-type seal mechanism is characterized in that it can be separated from the rotating shaft during non-operation, for example, when the balance before assembly is corrected. Of course, this disengagement includes contact in a state where contact is very small, that is, the contact allowance is reduced and does not affect the balance test.

  In order to realize a non-contact state with the rotary shaft during this non-operation (before assembly), first, the lip seal material is installed at the seal position, and second, the rotary shaft with which this seal material comes into contact. Three configurations that an annular concave portion having a constant width is formed on the circumferential surface of the rotating shaft in the vicinity of the position, and third, that the housing and the bearing mechanism or the rotating shaft and the bearing mechanism can be relatively displaced in the direction of the rotating shaft. Is required. That is, when the rotating shaft is mounted horizontally on the balance testing machine before the assembly, and the balance test is performed, the rotation shaft can be displaced relative to the lip seal material in the axial direction of the rotation shaft. The lip seal material can be in a non-contact state with the rotating shaft. The best mode of the present invention is an embodiment having the above-described three components and capable of realizing these functions reliably and easily.

  FIG. 1 shows the configuration of the present invention comprising the above three components. 1 shows a longitudinal section of a turbo-type high-speed rotating device as in FIG. 6, but a bearing holding member 8 for holding the upper bearing 5 is installed in the housing 1, and a seal plate 9 corresponding to a partition wall is provided above it. Is mounted on the housing 1. The rotating shaft 4 is provided through the through hole 9H of the seal plate 9. A lip seal material 10 is attached to the inner side of the through hole 9H of the seal plate 9, and its inner end is in contact with the outer peripheral surface of the rotating shaft 4 as shown in the figure. A small-diameter portion 4K, which is an annular recess, is formed in the vicinity of the upper portion of the rotating shaft 4 with which the lip seal material 10 is in sliding contact. When the rotary shaft 4 is displaced and the lip seal material 10 is positioned at the small diameter portion 4K, the contact with the rotary shaft 4 is cut off. In FIG. 1, 11 is a bolt for fixing the bearing holding member 8 and the seal plate 9 to the housing 1, and 12 is a holding spring for holding the rotating shaft 4 and the turbo blade 7 in a floating state. In FIG. 1, parts denoted by the same reference numerals as those in FIG. 6 are the same as those in FIG. 6, and descriptions of their functions and operations are omitted.

  In the above configuration, the configuration and operation of the turbo type high-speed rotating device of the present invention will be described with respect to the first embodiment shown in FIG. The first embodiment employs a configuration in which relative displacement is performed between the rotating shaft 4 and the upper bearing 5 and the lower bearing 6 of the bearing mechanism, and the lip seal material 10 is detached from the rotating shaft 4. The specific configuration for causing this displacement is that the fitting relationship between the inner diameters of the upper and lower bearings 5 and 6 and the outer diameter of the rotary shaft 4 is a loose fitting relationship. Thus, the rotary shaft 4 can be displaced relatively easily in the axial direction. Therefore, the outer bearing of the upper bearing 5 is fixedly held by the bearing holding member 8, and the rotary shaft 4 can be easily slid by the external force with respect to the inner cases of the upper bearing 5 and the lower bearing 6. The upper bearing 5 and the lower bearing 6 are angular contact types.

  When assembling the turbo-type high-speed rotating device of the first embodiment, a balancing test is performed from the need to remove the unbalance of the rotating body as described above. FIG. 2 shows the state of this balancing test. The rotating body (such as the turbo blade 7 and the rotating shaft 4) and the upper and lower bearings 5 and 6 are removed from the turbo type high-speed rotating device and mounted on the balance testing machine 13. In this case, the bearing holding member 8 and the seal plate 9 are integrated and fixed to the balance testing machine 13 using the bolts 11. FIG. 2 shows this state. The balance test is performed by rotating the rotary shaft 4 and the turbo blade 7 at a high speed by a rotary drive mechanism (not shown). At this time, it is necessary to prevent the inner end of the lip seal material 10 from contacting the rotary shaft 4. As shown in FIG. 3, an external force is applied by the operating member 14 to displace the rotating shaft 4 to the right. Then, the rotating shaft 4 is slidable with respect to both the upper and lower bearings 5 and 6, and is displaced as shown in FIG. Due to this displacement, the lip seal material 10 is detached from the rotating shaft 4, or the contact allowance is reduced to ensure a normal balance test. 2 and 3 are the same as those shown in FIG. 6, and the description of their functions and operations is omitted.

  A second embodiment relating to the present invention is shown in FIG. FIG. 4 shows a state where the rotating body part of the turbo type high-speed rotating device such as the turbo blade 7 and the rotating shaft 4 is taken out and mounted on the balance testing machine 13 in order to test the unbalanced state as in FIG. . The feature of the second embodiment is that the upper bearing 5 is engaged with the bearing holding member 8 so as to be slidable in the axial direction of the rotary shaft 4, and the lower bearing 6 is slidably engaged in the axial direction. And in particular, a compression spring 15 is interposed between the outer race of the upper bearing 5 and the bearing holding member 8. Therefore, as shown in FIG. 5, when the balance test is performed in the horizontal direction and mounted on the balance tester 13, the compression spring 15 extends and the upper bearing 5 is displaced rightward by the elasticity. Since the upper bearing 5 and the rotating shaft 4 are integrally fixed, the rotating shaft 4 is also displaced in the axial direction in accordance with the displacement of the upper bearing 5. As shown in FIG. To the position. Due to this displacement, the inner end of the lip seal material 10 is detached from the rotating shaft 4, or the contact allowance is reduced to ensure a normal balance test. 4 and 5 are the same as those shown in FIG. 6 and the description of their functions and operations is omitted.

The high-speed rotating device provided by the present invention is as described in detail above, but the configuration of the invention is not limited to the configuration described above or in the first or second embodiment, and includes various modifications.
First, the concave portion formed in the rotating shaft 4 may be formed in a shape in which an annular concave portion having a semicircular cross section is formed in addition to the step of reducing the diameter of the rotating shaft 4 as shown in FIGS. it can. In short, when the rotary shaft 4 is displaced in the axial direction, the inner end of the lip seal material 10 fixedly held with respect to the housing 1 is not in contact with the peripheral surface of the rotary shaft 4 or the contact allowance is reduced. It is sufficient that a state to be formed is formed, and the annular recess is not limited to a specific shape. Also, the bending direction of the lip seal material 10 can be reversed from the illustrated example, and the displacement direction of the rotary shaft 4 can be reversed with respect to the bending direction of the lip seal material 10. The shape of the lip seal material 10 includes not only a conical shape having a curved section as in the illustrated example, but also a conical shape having a straight section. Although the example which performs the displacement to the axial center direction of the rotating shaft 4 with the coil-shaped compression spring 15 was shown, a plate-shaped spring and a plate-shaped spring can also be utilized. Although an example in which the partition wall that partitions the gas compression chamber C and the motor chamber M is configured by the seal plate 9 that is separate from the housing 1 is shown, the partition wall may be configured by a part of the housing 1. In the case of the illustrated example, the bearing holding member 8 and a separate member are used, but it is also possible to integrate both. Further, the configuration of the turbo type high-speed rotating device not directly related to the features of the present invention, such as the lubrication mechanism of the upper and lower bearings 5 and 6, is not limited to the illustrated example. Further, in the balance testing machine 13 shown in FIGS. 2 to 5, the example in which the lower bearing 6 is directly mounted on the balance testing machine 13 has been shown. However, the lower bearing 6 is mounted via the holding frame of the lower bearing 6. The configuration of the balance test method and the balance test machine is not limited to the above and illustrated examples. The present invention can also be used as a high-speed rotating device other than a device that compresses and supplies gas to a laser oscillator.

It is a longitudinal cross-sectional view which shows the structure of this invention. It is a figure for demonstrating the structure of Example 1 of this invention. It is a figure for demonstrating the function of Example 1 of this invention. It is a figure for demonstrating the structure of Example 2 of this invention. It is a figure for demonstrating the function of Example 2 of this invention. It is a longitudinal cross-sectional view which shows the structure of the conventional high-speed rotation apparatus.

Explanation of symbols

1 Housing 1A Through hole
1H Exhaust port 1K Intake port 1Y Oil tank 2 Motor 2K Electrode coil 2M Rotor 3 Inverter 4 Rotating shaft 4S Mounting shaft 4H Hollow hole 4K Small diameter portion 4T Injection hole 5 Upper bearing 6 Lower bearing 7 Turbo blade 8 Bearing holding member 9 Seal plate 9H Through-hole 10 Lip seal material 11 Bolt 12 Spring 13 Balance testing machine 14 Actuating member 15 Compression spring R Exhaust pipe VP Vacuum pump C Gas compression chamber M Motor chamber S Seal portion L Oil W Partition wall

Claims (3)

  A turbo blade that performs gas compression, a motor that drives the turbo blade to rotate at high speed, a rotary shaft that is vertically disposed to connect the two, and an upper bearing and a lower bearing that rotatably hold the rotary shaft. A bearing mechanism is provided in the housing, and a gas compression chamber in which the turbo blades are disposed and a partition wall that partitions the motor chamber in which the bearing mechanism and the motor are disposed are installed in the housing, and the rotation is performed on the partition wall. A through-hole that penetrates the shaft is drilled, and a conical lip seal material extending inward from the partition wall is provided between the through-hole and the rotating shaft. Is a turbo high-speed rotating device configured to have a sealing function between the rotating shaft and the through hole when the pump is operated. In the vicinity An annular recess is formed in the rotating shaft, and a means for displacing the rotating shaft in the axial direction of the lip seal material is provided, and the position of the annular recess reaches the lip seal material position due to the displacement of the rotating shaft, A turbo type high-speed rotating device characterized in that the lip seal material can be detached from the peripheral surface of the rotating shaft or the contact allowance can be reduced.   The means for displacing is configured such that the rotating shaft is slidably engaged with the bearing mechanism in the axial direction, and the rotating shaft is displaced when an external force acts in the rotating axis direction. The turbo-type high-speed rotating device according to claim 1. The means for displacing is configured such that the bearing mechanism is slidably engaged with the housing in the axial direction, and a compression-type elastic means is interposed between the housing and the bearing mechanism. Item 4. A turbo-type high-speed rotating device according to item 1.

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