JP4543828B2 - High speed rotating equipment - Google Patents

Description

  The present invention relates to a high-speed rotating device that includes a turbo blade and exhausts gas or the like by its rotation.

  This type of turbo rotating device includes a turbo blade for exhausting gas, a rotating shaft protruding from the bottom surface of the turbo blade, and a rolling device that rotatably supports the rotating shaft by using lubrication with lubricating oil. A bearing, a lubricating oil reservoir for storing lubricating oil in the downward direction of the rotating shaft, and an oil supply hole drilled inward at the center axis of the rotating shaft, sucking up the lubricating oil from below and rolling. One having a lubricating oil supply mechanism for supplying a bearing is known. FIG. 5 shows a basic configuration of this conventional turbo rotating device.

  The turbo rotating device shown in FIG. 5 compresses and exhausts gas with a turbo blade 1, and includes a housing 5, a turbo blade 1, and a rotating shaft 2 that integrally extends from the bottom surface of the turbo blade 1. The centrifugal bearing is provided with a rolling bearing 3 that rotatably supports the rotating shaft 2 and an electric motor 4 that rotates the rotating shaft 2. The rotating shaft 2 is erected.

  The housing 5 includes a gas compression chamber 51 that houses the turbo blade 1, and a bearing holding chamber 52 that is provided continuously at the lower end of the gas compression chamber 51 and in which the rotary shaft 2 is loosely fitted. The gas compression chamber 51 includes a gas introduction port 53 that opens toward the top of each turbo blade 1, and a gas discharge port 54 that opens to the side of the turbo blade 1. The bearing holding chamber 52 is provided in the vicinity of the center thereof, and is provided with a motor arrangement portion 55 for arranging an electric motor 4 to be described later, and above and below the motor arrangement portion 55, and the rolling bearing 3 is provided. And a lubricating oil storage part 22 for storing lubricating oil JL, which is provided at the lower end part and is a lubricating liquid for bearing lubrication.

  The turbo blade 1 is a generally known one in which a plurality of blade bodies 12 are installed in a spiral shape on a slope portion of a truncated conical base body 11. Further, the rolling bearings 3 are supported by the bearing arrangement portion 56 and are respectively disposed above and below the electric motor 4. In this embodiment, an angular type is adopted as the rolling bearing 3 so that both loads acting in the journal direction and the thrust direction can be supported.

  A lubricating oil supply hole 21 is bored inside the central axis of the rotating shaft 2. The lubricating oil supply hole 21 is opened at the lower end surface of the rotary shaft 2, and the opening is immersed in the lubricating oil JL in the lubricating oil reservoir 22. Moreover, it is comprised so that it may each open also to the outer peripheral surface of the rotating shaft 2 in the upper side of each rolling bearing 3. FIG. The lower end portion 21A of the lubricating oil supply hole 21 is configured to function as a centrifugal pump portion. In other words, specifically, it has a tapered shape whose cross-sectional area decreases downward. Therefore, the lubricating oil JL is raised from the lubricating oil reservoir 22 along the tapered surface by the centrifugal force generated by the rotation of the rotating shaft 2, and the sucked lubricating oil JL is injected from the openings 2H provided on the outer peripheral surface of the rotating shaft 2, respectively. Thus, each roller bearing 3 can be supplied. The lubricating oil JL also exists in a sprayed state in the bearing holding chamber 52 due to the rotation of the rotating shaft 2.

The electric motor 4 is, for example, a DC brushless type in which the rotor 4R is externally fitted and fixed to the rotary shaft 2 and the stator 4S is disposed around the rotor 4R and supported by the housing 5; It is provided integrally with the rotating shaft 2 and directly drives the rotating shaft 2. In this embodiment, an inverter (not shown) is used as a drive source for the electric motor 4. Reference numeral 4C denotes a coil of the stator 4S.
JP 2003-301799 A

  By the way, a high-frequency AC electric motor is used as the electric motor. In this type of electric motor, a loss occurs on the stator side (coil 4C of the stator 4S). That is, the stator 4S is configured by winding the coil 4C around the silicon copper plate, but the primary copper loss (in the coil) and the iron loss (in the silicon copper plate) are within the stator 4S when the electric motor is operated. Loss occurs and heat is generated.

  In addition, the electric motor 4 is disposed on the exhaust system side as shown in FIG. 5, is in a low pressure region, has low heat transfer from the end of the coil 4C of the stator 4S to the surrounding gas, and therefore has a higher temperature. It tends to be.

  In order to solve such a problem, a SUS pipe 23 is embedded in the housing 5 as a cooling water channel by winding the electric motor 4 in a spiral shape, for example. However, the housing 5 is formed of, for example, an aluminum casting, and due to the properties of the casting, there is a minute gap between the outer peripheral surface of the pipe 23 and the housing 5, so that the adhesion is poor, so that the cooling efficiency is improved. It is an impediment. In order to improve the cooling efficiency, a measure for increasing the amount of the cooling water can be considered, but this is not a fundamental solution and has a problem that the running cost increases.

  As described above, in the conventional high-speed rotating device, it is a big problem to improve the cooling efficiency by the cooling means for suppressing the temperature rise of the coil 4C of the stator 4S of the electric motor 4, but the present invention is like this. It is intended to provide a high-speed rotating device that solves various problems.

In order to solve the above-described problems, a high-speed rotating device provided by the present invention includes a turbo blade for performing gas exhaust and the like, a rotating shaft integrally protruding from the turbo blade, and a housing including the rotating shaft. An electric motor that is disposed around the motor and rotates the rotating shaft, a rolling bearing that rotatably supports the rotating shaft using lubrication oil, and stores the lubricating oil in the lower direction of the rotating shaft. A lubricating oil reservoir; a lubricating oil supply mechanism that is perforated inside the central axis of the rotating shaft and has an oil supply hole facing downward; and sucks the lubricating oil from below and supplies it to the rolling bearing; and the electric motor In the high-speed rotating device provided with a cooling pipe around the housing, the housing is characterized in that a liquid storage portion is formed in the housing around which the cooling pipe is exposed around the electric motor .

  Moreover, you may use the same kind as the said lubricating oil as a liquid stored in the said liquid storage part.

  Further, the liquid reservoir may be provided with a flow path communicating with the lubricant reservoir or the outside of the stator through a valve, or the liquid reservoir may be closed so that the liquid inside is not exposed to the outside. .

  Since the high-speed rotating device provided by the present invention is as described in detail above, the stator of the electric motor can be efficiently cooled, and the temperature increase of the electric motor in a low pressure environment can be prevented.

  Hereinafter, the high-speed rotating device provided by the present invention will be described with reference to the embodiments shown in FIGS. FIG. 1 is a cross-sectional view showing a basic configuration of an embodiment applied to a high-speed rotating device according to the present invention, for example, a vacuum pump, and FIG. 2 is a partial cross-sectional view around a liquid storage portion 31 in FIG.

  As shown in FIG. 1, the rotating shaft 2 is disposed so as to be suspended from the central portion of the housing 5, and is rotatably held by two upper and lower rolling bearings 3. The turbo blade 1 is fixedly held above the rotating shaft 2 and is driven to rotate by the operation of the electric motor 4 so that the exhaust gas is compressed. On the other hand, the rotating shaft 2 has a lubricating oil supply hole 21 for supplying the lubricating oil JL to the upper rolling bearing 3 in the center of the inner side, so that the lubricating oil JL moves upward from the lower lubricating oil reservoir 22. And is supplied to the outside through the opening 2H to lubricate each rolling bearing 3. The components and structures indicated by the same reference numerals as those in FIG. 5 perform the same functions as those in FIG. 5 and will not be described in detail.

  In the above configuration, in the high-speed rotating device according to the present invention, the SUS pipe 23 is wound around the electric motor 4 in a spiral shape, for example, as a cooling water channel in the housing 5 formed of an aluminum casting or the like. While being embedded in the housing 5, a space is formed in the housing 5 so that at least a part of the pipe 23 is exposed, and liquid such as oil CL is accommodated in the liquid storage portion 31 formed of this space. Even if the stored oil CL has irregularities due to casting on the surface of the liquid reservoir 31, the oil CL penetrates into the irregularities of the liquid reservoir 31 and comes into close contact with the surface without a gap. The pipe 23 is detachably unitized with respect to the housing 5 so that it can be easily replaced during maintenance.

  Then, by flowing and circulating the cooling water from the external cooling water supply source to the pipe 23, the cold heat is propagated through the pipe 23 to the oil CL in the liquid reservoir 31 to cool the housing 5. At this time, since the water in the housing 5 is in close contact with the surface of the liquid storage portion 31, cold heat is transmitted to the housing 5 without unevenness. The temperature rise of the coil 4C of the stator 4S of the motor 4 can be effectively suppressed.

  Note that aspects described below are also included in the present invention. That is, the oil CL stored in the liquid storage unit 23 may use the same type of oil as the lubricating oil. Accordingly, it is not necessary to separately prepare a liquid such as cooling oil, which is economical and easy to manage. In addition to oil, water or the like may be used.

  Further, as shown in FIG. 3, a flow path 35 that connects the liquid reservoir 31 and the lubricating oil reservoir 22 via the valve 34 is provided, or the liquid reservoir 31 and the outside of the housing 5 are connected to the valve 34. When the oil CL in the liquid storage unit 31 is replaced, the oil CL can be easily discharged.

  Furthermore, as shown in FIG. 4, the opening of the liquid reservoir 31 is closed with a lid 38 so that the internal oil CL is not exposed to the outside, so that the operation is performed when the oil CL used for storage is different from the lubricating oil. In addition, it is possible to prevent the oil CL stored in the liquid storage unit 31 from being oxidized and deteriorated due to ozone or the like generated during CO2 laser oscillation, particularly when used for gas circulation of a CO2 laser. it can. In this structure, the oil CL is supplied from the flow path 37 communicating with the liquid storage section 31 through the valve 36, and the liquid storage section 31 is supplied by the flow path 35 through the valve 34 as in FIG. Oil CL is discharged from the tank.

It is sectional drawing which shows the basic composition of the high-speed rotation apparatus by this invention. It is a fragmentary sectional view (1) of one Example of the high-speed rotation apparatus by this invention. It is a fragmentary sectional view (2) of one Example of the high-speed rotation apparatus by this invention. It is a fragmentary sectional view (3) of one Example of the high-speed rotation apparatus by this invention. It is sectional drawing which shows the basic composition of the conventional high-speed rotation apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Turbo blade 2 Rotating shaft 3 Rolling bearing 4 Electric motor 22 Lubricating oil storage part 23 Pipe (cooling water channel)
31 Liquid reservoir CL Oil

Claims (4)

A turbo blade for performing gas exhaust and the like, a rotating shaft integrally protruding from the turbo blade, an electric motor disposed around the rotating shaft and rotating the rotating shaft, and a lubricating oil A rolling bearing that rotatably supports the rotating shaft by using lubrication by a lubricant, a lubricating oil storage portion that stores the lubricating oil in a lower direction of the rotating shaft, and an inward center axis of the rotating shaft. In the high-speed rotating device provided with a lubricating oil supply mechanism that has an oil supply hole facing downward and sucks the lubricating oil from below and supplies it to the rolling bearing, and a cooling pipe around the electric motor, the housing Is a high-speed rotating device in which a liquid storage portion is formed around the electric motor so that the cooling pipe is exposed . The high-speed rotating device according to claim 1, wherein the liquid stored in the liquid storage unit is the same type as the lubricating oil. The high-speed rotating device according to claim 1, wherein the liquid reservoir is provided with a flow path that communicates with the lubricant reservoir or the outside of the stator via a valve. The high-speed rotating device according to claim 1, wherein the liquid storage unit is closed so that an internal liquid is not exposed to the outside.

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