JP2006125315A - Turbo type high-speed rotary apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a turbo type high-speed rotary apparatus preventing oil for bearing lubrication from being excess in a bearing. <P>SOLUTION: A fixed horizontal surface from a circumference end of a tapered surface T of a bearing retaining board 10 is provided, outer circumference end is thick, and reservoir part 10P for oil L is formed at the circumference end of the tapered surface T by the tapered surface T and the thick part of the outer circumference end. Simultaneously, a through-hole 10A is bored near the circumference end of the tapered surface T, namely on a bottom plate of the reservoir part 10P. A porous body 13 is embedded in each through-hole 10A. The porous body 13 is embedded to be air-tightly fitted to the through-hole 10A , and oil mist from a motor chamber M at a lower part is prevented from flowing into a gas compression chamber C at an upper part from the through-hole 10A when oil L flows in. Namely, a trap is constructed. A slinger 12 is fitted in an upper part of the bearing retaining board 10 to guide oil L to the bearing retaining board 10. <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 pivotally supported by a mechanical bearing and is provided with 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. 5, and the turbo blade 7 is rotatably disposed inside the housing 1 at the upper portion thereof. 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.

  By the way, as shown in FIG. 5, the rotary shaft 4 has a hollow hole 4H formed on the shaft center. 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 the spray-like oil L in the motor chamber M improves the lubrication in the upper bearing 5 and the lower bearing 6, but when this oil mist flows into the gas compression chamber C, it flows into a laser oscillator or the like, causing laser oscillation. Reduce functionality.

  Therefore, the gas compression chamber C and the motor chamber M are blocked by the seal portion S in the partition wall portion made of a member integral with the housing 1 or the housing 1. That is, the housing 1 is provided with a through hole 1A having a minimum diameter within a range in which the rotary shaft 4 can pass through in a non-contact manner at a position above the upper bearing 5, and a seal portion S is formed in cooperation with the rotary shaft 4. Yes. 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. In addition to labyrinth seals, gas seals with a small parallel gap of several microns are also used.

  On the other hand, the motor chamber M is evacuated to a 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 from the small gap in the seal portion S as described above.

As described above, in the turbo type high-speed rotating device used for the laser oscillator, the existence and countermeasure of the oil L mist are important, but the existence of the oil L that is the source of the mist cannot be ignored. In particular, it is necessary to prevent the oil L discharged from the injection hole 4T of the rotating shaft 4 from reaching the upper seal portion S as much as possible. For this purpose, as shown in FIG. 4, a device has been proposed in which a bearing holding member 9 that holds the upper bearing 5 is integrally installed in the housing 1.
FIG. 4 is a longitudinal sectional view schematically showing the configuration of a conventional turbo type high-speed rotating device as in FIG. The configuration of FIG. 4 differs from the configuration of FIG. 5 in the method of holding the upper bearing 5, and in the case of FIG. 5, the housing 1 directly holds the upper bearing 5, but FIG. 9 is provided separately, and the bearing holding member 9 is integrally installed in the housing 1. At the same time, the seal member 8 constituting the seal portion S is also formed separately from the housing 1. Reference numeral 11 denotes a fixing screw that integrally fixes the seal member 8 and the bearing holding member 9 to the housing 1. Reference numeral 8 </ b> A denotes a through hole formed in the seal member 8. 4 that have the same reference numerals as those in FIG. 5 have the same functions as those in FIG. 5, and a detailed description thereof will be omitted.

In such a configuration, the bearing holding member 9 has a through hole 9 </ b> H of the rotating shaft 4 at the center, and therefore has a certain gap with the rotating shaft 4. By reducing this gap, it is possible to reduce the oil L supplied to the upper bearing 5 from flowing into the seal portion S.
Japanese Unexamined Patent Publication No. 2000-209815 (page 1-3, FIGS. 1-8)

  However, the conventional bearing mechanism has the following two problems. First, if the amount of oil L injected from the injection hole 4T of the rotary shaft 4 and the amount of oil L entering the upper bearing 5 are not balanced, and the injection amount from the injection hole 4T is too large, a part of the bearing is retained. The oil L flows upward through a gap between the through hole 9 </ b> H of the member 9 and the rotating shaft 4, and the oil L is ejected to the upper surface of the bearing holding member 9. Second, when the upper bearing 5 has a structure in which the oil L always enters the bearing, if the supply of the oil L from the rotating shaft 4 is too much, the loss of the bearing increases and the loss increases.

Regarding the first problem, the mist of the oil L generated in the motor chamber M flows into the upper gas compression chamber C through the gap of the seal portion S. As for the second problem, it is necessary to increase the exhaust amount of the motor chamber M due to the destruction of the upper bearing 5 or the like, and when used for a laser transmitter, the gas consumption is large and the running cost is increased.
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, a turbo-type high-speed rotating device provided by the present invention is a bearing holding plate that is installed integrally with a housing and has a through hole of the rotating shaft in the center to hold the upper bearing mechanism. In addition, an umbrella-shaped taper portion is formed on the upper surface of the bearing holding plate, and a porous portion that allows oil to drip downward is installed at the peripheral end portion of the taper portion. Therefore, the oil that has flowed to the upper side of the bearing holding plate flows down the tapered surface and drops through the porous portion. Further, the oil mist on the motor chamber side is prevented from rising from the portion where the oil drips to the storage portion side by the porous portion, and is trapped.

  When the oil for lubrication supplied from the rotating shaft is excessive due to the interposition of the bearing holding plate, the upward flow is facilitated and the oil flows down on the taper surface, and the upper bearing is in an excessive oil state. It is less likely to continue. On the other hand, the oil that has flowed down the tapered surface is dropped downward through the porous body to circulate the oil, and the oil is retained in the porous body, so that the oil mist in the motor chamber flows upward. Will be trapped.

  The feature of the turbo-type high-speed rotating device provided by the present invention is that it is configured to prevent the upper bearing from becoming excessive due to too much lubricating oil supplied from the rotating shaft, For this purpose, a configuration that allows upward flow from the upper bearing, a configuration in which oil that has flowed upward flows down through the taper surface of the bearing holding plate, and oil that has flowed down the taper surface drops downward through the porous body. It is a basic condition to have a configuration to make it. The bearing retainer has a central hole that allows the rotation shaft to pass therethrough, and a certain gap is provided between the center hole and the rotation shaft, but this gap is not allowed to enter a large amount of oil into the upper bearing. A configuration that is set slightly larger and allows upward flow is desirable. Further, it is desirable that the oil flowing down the tapered surface smoothly flows into the porous portion and is immersed in the oil. A configuration capable of maintaining this state is the best mode.

The configuration of a turbo type high-speed rotating device provided by the present invention is shown in FIG. FIG. 1 shows a longitudinal section similar to FIGS.
A feature of the present invention lies in the shape of a bearing holding disk 10 that holds the upper bearing 5 with respect to the housing 1, and the excess oil is supplied upward without the oil L supplied from the rotating shaft side staying in the upper bearing 5. The oil L that has flowed and flowed upward is caused to flow down on the tapered surface T and flow into the porous body 13 constituting the porous portion. That is, in FIG. 1, reference numeral 10 denotes a bearing holding plate for holding the upper bearing 5, which has a disk shape and has a central hole 10H for penetrating the rotating shaft 4 in the central portion and an outer peripheral end portion. Is provided with a mounting hole 10K for fixing to the housing 1 integrally. The bearing holding disk 10 is fixed to the housing 1 together with the seal member 8 by a fixing screw 11. Further, as shown in the figure, the bearing holding disk 10 has a flesh portion that is raised upward at the center, and is formed with a tapered surface T that extends downward from the periphery of the center hole 10H.

  FIG. 2 is an enlarged view showing the bearing holding disk 10 in an enlarged manner. As is clear from FIG. 2, the bearing holding disk 10 has a certain horizontal surface from the peripheral edge of the tapered surface T and an outer peripheral edge portion. Is thick, and the mounting hole 10K is formed in the thick portion. Accordingly, the oil L reservoir 10P is formed at the peripheral end of the tapered surface T by the tapered surface T and the thickened portion of the outer peripheral end. At the same time, in the vicinity of the peripheral end of the tapered surface T, that is, the bottom plate of the storage portion 10P, a passage portion for dropping the oil L downward is installed.

  Specifically, the passage portion is configured as follows. A through hole 10A is formed in the bottom plate of the reservoir 10P. For example, four through-holes 10A are formed at equal intervals around the circumference, and a porous body 13 is embedded in each through-hole 10A as shown in FIG. The embedment of the porous body 13 is airtightly fitted into the through hole 10A so that oil mist from the lower motor chamber M does not flow from the through hole 10A into the upper gas compression chamber C when the oil L flows. That is, it is configured to be trapped. Specifically, a porous sintered metal or the like is applied as the porous body 13. Further, a slinger 12 is fitted on the rotary shaft 4 above the bearing holding plate 10. The slinger 12 is interposed so that the oil L flowing upward from the upper bearing 5 is prevented from flowing out into the through hole 8A, and the oil L is guided to the bearing holding plate 10.

In the embodiment shown in FIG. 3, the passage portion installed in the bearing holding board 10 is configured differently from the first embodiment. That is, FIG. 3 shows only the passage portion of the bearing holding plate 10 in an enlarged manner, but the bearing holding plate 10 has a plurality of pores 10S forming the passage portion. By the formation of the plurality of pores 10S, the oil L gradually flows down and drops through the pores 10S.
In addition, although two embodiments have been described above, the parts denoted by the same reference numerals in FIGS. 1, 2 and 3 as those in FIGS. 4 and 5 have the same functions as those in FIGS. Detailed description will be omitted.

  Since the present invention is configured as described above, when the turbo type high-speed rotating device is operated and the oil L is supplied to the upper bearing 5 from the injection hole 4T of the rotating shaft 4, the oil L is supplied to the upper bearing 5. Is done. When the supply amount becomes excessive, the oil L flows upward, is blocked by the slinger 12, and is guided to the upper surface of the bearing holding plate 10. The oil L led to the upper surface flows in the outer peripheral direction, flows down the tapered surface T, and is stored in the storage portion 10P. In this case, since the porous body 13 that is a porous portion is provided, the oil L penetrates into the porous body 13. The oil L gradually descends in the porous body 13 and drops down below the housing 1, that is, to the oil tank 1Y. Each of the porous bodies 13 is soaked and filled with oil L so that the bearing holding disk 10 functions as a sealed disk and traps oil mist in the motor chamber M.

  The features of the turbo-type high-speed rotating device provided by the present invention are as described in detail above, but are not limited to the above and illustrated examples, and include various modifications. In particular, regarding the welfare of the passing portion, in the illustrated example, a through hole 10A is formed in the vicinity of the peripheral end of the tapered surface T of the bearing holding plate 10, and the porous body 13 is embedded in the through hole 10A, and the bearing holding plate. Although the example in which the pores 10S are drilled in the 10 itself has been shown, in addition to these methods, a modified example in which a mesh (mesh) is embedded or inserted in the through hole 10A or a part of the bearing holding board 10 itself is meshed. A modification example (mesh) is also conceivable. Furthermore, the outer peripheral surface portion (ring-shaped portion) having a constant width outward from the peripheral end of the tapered surface T of the bearing holding plate 10 can be formed of a porous material. That is, a ring-shaped porous material is interposed in the bearing holding plate 10. Thus, various modifications can be given for the passing portion.

It is a longitudinal cross-sectional view which shows the structure of this invention. It is a longitudinal cross-sectional view which expands and shows the principal part of the structure of this invention. It is a longitudinal cross-sectional view which expands and shows the principal part of the structure of the other Example of this invention. It is a longitudinal cross-sectional view which shows the conventional structure. It is a longitudinal cross-sectional view which shows the conventional structure.

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 4T Injection hole 5 Upper bearing 6 Lower bearing 7 Turbo blade 8 Seal member 8A Through hole 9 Bearing holding member 9H Through-hole 10 Bearing holding panel 10A Through-hole 10H Central hole 10K Mounting hole 10P Reservoir 10S Pore 11 Fixing screw 12 Slinger 13 Porous body R Exhaust pipe VP Vacuum pump C Gas compression chamber M Motor chamber S Seal portion T Taper Surface L Oil

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 couples the turbo blade, a dual bearing mechanism that rotatably holds the rotary shaft at an upper part and a lower part, and the turbo blade A gas compression chamber in which the motor is disposed and a partition wall that partitions the motor chamber in which the bearing mechanism and the motor are disposed are provided in the housing, and a through-hole that penetrates the rotating shaft is formed in the partition wall. A sealing mechanism is provided between the through hole and the rotating shaft, and a hollow hole is formed on the rotating shaft on the shaft center, and a lower portion of the inner hole below the hollow hole is immersed in lubricating oil. A lubricating mechanism is provided for lubricating the upper bearing mechanism by the oil rising inward of the hollow hole by the action of centrifugal force due to the rotation of the rotating shaft and being injected from the upper injection hole. Gas from the mouth In a high-speed rotating device that shrinks and discharges to an exhaust port, a bearing holding plate that is installed integrally with a housing and has a through hole of the rotating shaft in the center to hold the upper bearing mechanism is provided. The upper surface of the cylinder is formed so that the oil flows down, and at the peripheral end portion of the bearing holding plate, a passage portion that allows the oil to pass and drop downward is installed. machine.   The turbo-type high-speed rotating device according to claim 1, wherein the passage portion is composed of a through hole formed in the vicinity of a peripheral end portion of the bearing holding plate and a porous body embedded in the through hole.   The turbo-type high-speed rotating device according to claim 1, wherein the passage portion is constituted by a through hole formed in the vicinity of a peripheral end portion of the bearing holding plate.

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