JPH0683990U - Turbo molecular pump - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a highly reliable turbo molecular pump capable of reliably preventing uncontrollability of a rotor caused by corrosive gas. [Structure] A purge port 20 is provided on the outer peripheral surface of the spacer 11. One end of the purge port 20 is formed so as to communicate with the passage 11a of the spacer 11 and is arranged at a position adjacent to one end of the terminal portion 12a arranged so as to be exposed in the passage 11a. In other words, the purge port 20 cannot supply sufficient purge gas with the conventional purge port that supplies the purge gas using the wear-prone portion as the flow path, such as the protective dry bearing 15, that is, the terminal portion 12a. The purge gas is directly supplied to one end side to block the connecting portion between the terminal portion 12a and the control line 13 from the corrosive gas to prevent the connecting portion from being corroded.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention mainly relates to a turbo molecular pump used as an exhaust device for corrosive gas, and in particular, cannot control the rotor caused by the corrosive gas, for example, control for adjusting the rotational speed of the rotor or supporting the rotor at a fixed position. This is to ensure that the loss of control can be prevented.

[0002]

[Prior art]

 Conventionally, as shown in FIG. 5, a turbo molecular pump of this type has a rotor 1 and a rotor shaft 3 each having an opening at one end arranged inside a casing 1. One end of the rotor shaft 3 is located on the inner bottom surface of the rotor 2. It is fixed and rotatably provided integrally with the rotor 2.

Further, between the casing 1 and the rotor 2, rotor blades 4 and stator blades 5 are alternately arranged along the axial direction of the rotor 2. On the outer peripheral surface of the stator 1, the stator blades 5 are attached to the inner wall surface of the casing 1, while on the other hand, a stator column 6 is provided between the rotor 2 and the rotor shaft 3. It is fixed to the base portion 1c of No. 1.

Further, electric components 9 such as a drive motor 7 and a magnetic bearing 8 are installed inside the casing 1, and these electric components 9, that is, the drive motor 7 and the magnetic bearing 8 are attached to the stator. They are arranged between the column 6 and the rotor shaft 3, respectively. The drive motor 7 rotates the rotor 2 around its axis integrally with the rotor shaft 3, and the magnetic bearing 8 is configured to support the rotor 2 at a fixed position by magnetic force.

On the other hand, the base portion 1c of the casing 1 has an opening 10, a spacer 11 is attached to the opening 10, and a spacer 11 is formed with a passage 11a. Is provided so that one end communicates with the inside of the casing 1 through the opening 10 and the other end communicates with the outside of the casing 1.

Further, a connector 12 is attached to the spacer 11, that is, the connector 12 is attached to the base portion 1c of the casing 1 via the spacer 11 and has a terminal portion 12a. Is provided so that one end is exposed to the passage 11a and the other end is exposed to the outside of the casing 1.

A control wire 13 is fixed to one end of the terminal portion 12a by soldering, and the control wire 13 is an electrical component 9 (driving motor 7 and magnetic bearing 8) via the terminal portion 12a. And a control unit 14 installed outside the casing 1 and controlling the electric component 9 by the control unit 14, for example, controlling the rotational speed of the rotor 2 when the electric component 9 is a drive motor 7. When the electrical component 9 is the magnetic bearing 8, control is performed to adjust the exciting current of the electromagnet to support the rotor 2 at a fixed position.

That is, in this turbo-molecular pump, when the rotor 2 rotates while floating integrally with the rotor shaft 3 in a fixed position, a molecular flow is induced between the rotor blades 4 and the stator blades 5, which causes suction. The gas in the vacuum chamber (not shown) is sucked into the casing 1 from the port 1a, and the gas thus sucked is discharged from the exhaust port (not shown) to the outside of the casing 1. .

A protective dry bearing 15 is provided in the vicinity of the rotor shaft 3. The protective dry bearing 15 can be controlled to support the rotor 2 at a fixed position while the rotor 2 is rotating at high speed. It is configured to support and protect the rotor 2 when a so-called touchdown of the rotor 2 occurs, such as when the rotor 2 is disabled.

By the way, when such a turbo molecular pump is used as an exhaust device for corrosive gas, the corrosive gas is sucked and exhausted, and at the same time, a gap between the inside of the casing 1 and the rotor shaft 3 and the electrical component 9 is provided. Etc., purging gas such as inert gas is supplied, so-called gas purging is carried out, and the inert gas is introduced from the purge port 16 communicating with the inside of the casing 1, and the inner wall surface of the casing 1, The passages other than the corrosion-resistant portions such as the rotor blades 4, the stator blades 5, and the stator columns 6 are used as the flow passages, that is, the portions such as the dry bearing 15 for wear, the rotor shaft 3 and the electrical components 9 are worn. The gap is used as a flow path and the part is protected from corrosive gas.

[0011]

[Problems to be solved by the device]

 However, in such a conventional turbo molecular pump, as described above, the purge gas has a flow path through a portion where wear occurs, such as the protective dry bearing 15, so that one end of the terminal portion 12a and the control line 13 are connected to each other. A sufficient amount of purge gas is not supplied to the connection part of the above, and furthermore, the connection between one end of the terminal portion 12a and the control line 13 is made by soldering, and thus such a soldered part is corroded by insufficient supply of purge gas. As a result, one end of the terminal portion 12a and the control line 13 may cause poor contact or break, which makes it impossible to control the rotation speed of the rotor 2 or control the rotor 2 at a fixed position. However, there is a problem that the reliability of the turbo molecular pump is low.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a highly reliable turbo molecular pump capable of reliably preventing uncontrollability of a rotor caused by corrosive gas. is there.

[0013]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the invention according to claim 1 provides a rotor rotatably disposed inside a casing, a rotor blade attached to an outer peripheral surface of the rotor, and an inner wall surface of the casing. The stator blade attached to the housing, the drive motor installed inside the casing and rotating the rotor around its axis, or the electrical components such as magnetic bearings that support the rotor in a fixed position by magnetic force, and the casing A spacer having a passage formed therein, one end of which communicates with the inside and the other end of which communicates with the outside of the casing, is attached to the casing through the spacer, and one end of the spacer is exposed in the passage and the other end of the casing is exposed. Only connect the connector that has a terminal portion that is exposed to the outside, and connect the electrical component and the control portion that is provided outside the casing via the terminal portion. A turbo molecular pump having a control line for controlling electric components by a control unit, characterized in that a purge port for directly supplying a purge gas such as an inert gas is provided at one end of the terminal unit. .

Further, according to a second aspect of the invention, the rotor rotatably arranged inside the casing, the rotor blade attached to the outer peripheral surface of the rotor, and the inner wall surface of the casing are attached. Inside the casing, there are stator blades, electrical components such as a magnetic motor that is installed inside the casing and that rotates the rotor around its axis, or a magnetic bearing that supports the rotor at a fixed position by magnetic force. A spacer having a passage formed so that one end communicates with the other end communicates with the outside of the casing, and the spacer is attached to the casing through this spacer, and one end is exposed in the passage of the spacer and the other end is outside the casing. A connector having a terminal portion provided so as to be exposed to the outside, and the electric component and the control portion provided outside the casing are connected via the terminal portion, and the control portion is connected. In a turbo molecular pump having a control line for controlling electrical components by means of the above, an injection passage communicating with the passage of the spacer is formed on the outer peripheral surface of the spacer, and the injection passage and the passage of the spacer are used. And a molding agent for protecting one end of the terminal portion is provided.

[0015]

[Action]

 According to this invention, the purge gas having a high concentration is sufficiently supplied to the connecting portion between the one end of the terminal portion and the control line, and the corrosive gas is completely cut off.

Further, according to the second aspect of the invention, the connecting portion between the one end of the terminal portion and the control line is protected by the molding agent, and is completely shielded from the corrosive gas.

[0017]

【Example】

 Hereinafter, an embodiment of a turbo molecular pump according to the present invention will be described in detail with reference to FIGS. 1 to 4.

As shown in FIG. 1, a rotor 2 is rotatably disposed inside a casing 1. Rotor blades 4 are provided on an outer peripheral surface of the rotor 2 and an inner wall surface of the casing 1 is not provided. The stator blades 5 are attached, and electric components 9 such as a drive motor 7 and a magnetic bearing 8 are arranged inside the casing 1. The drive motor 7 rotates the rotor 2 about its axis. The magnetic bearing 8 supports the rotor 2 in a fixed position by magnetic force, a spacer 11 is attached to the opening 10 formed in the base portion 1c of the casing 1, and the spacer 11 is a passage. 11a, the connector 12 is mounted on the base 1c of the casing 1 through the spacer 11, and the terminal 12a of the connector 12 has one end exposed in the passage 11a and the other end. The control wire 13 is provided so as to be exposed to the outside of the connector 1, and the control wire 13 is fixed to one end of the terminal portion 12a by soldering. The control wire 13 is connected to the electrical component 9 through the terminal portion 12a. Since the control unit 14 and the control unit 14 are connected to each other and the control unit 14 controls the electric component 9 is the same as the conventional one, the same members are designated by the same reference numerals and detailed description thereof will be omitted.

As shown in FIG. 1, the turbo molecular pump is provided with a purge port 20 on the outer peripheral surface of the spacer 11, and one end of the purge port 20 is formed so as to communicate with the passage 11 a of the spacer 11. In addition, it is provided at a position adjacent to one end of the terminal portion 12a arranged so as to be exposed in the passage 11a.

The other end of the purge port 20 is connected to a gas supply device (not shown), and the gas supply device is configured to supply a purge gas such as an inert gas to the purge port 20.

That is, the purge port 20 is a conventional purge port 16 that supplies the purge gas through a flow path such as a portion where wear occurs, such as the protective dry bearing 15, a gap between the rotor shaft 3 and the electrical component 9, and the like (see FIG. 5). Unlike the above (see (1)), the conventional purge port 16 is configured to directly supply the purge gas to a portion where the purge gas cannot be sufficiently supplied, that is, one end side of the terminal portion 12a.

Therefore, in the turbo molecular pump of the above-described embodiment, the connecting portion between the one end of the terminal portion and the control wire is sufficiently supplied with the high-concentration purge gas and completely shielded from the corrosive gas. , The connection part is corroded due to insufficient supply of purge gas, or such corrosion causes poor contact between the one end of the terminal part and the control line or disconnection. The control for supporting the position is not lost, that is, it is possible to reliably prevent the control failure of the rotor caused by the corrosive gas.

As the inert gas used as the purge gas as described above, for example, nitrogen gas can be used. Further, as shown in FIG. 2, the purge port 20 of this embodiment and the conventional purge port 16 are used. Of course, both may be installed together.

FIG. 3 shows another embodiment of the present invention. Since the basic configuration of the turbo molecular pump shown in FIG. 3 is the same as the above embodiment, the same members are designated by the same reference numerals, Detailed description thereof will be omitted.

The turbo molecular pump shown in the figure is provided with an injection passage 21 on the outer peripheral surface of the spacer 11. One end of this injection passage 21 communicates with the passage 11 a of the spacer 11 and the other end is outside the spacer 11. It is formed so as to open toward.

A molding agent injector 22 is detachably connected to the injection path 21 as shown in FIG. 4, and the molding agent injector 22 is connected to the injection path 21 and the spacer 11. The liquid molding agent 23 is injected into the one end side of the terminal portion 12a through the passage 11a. When the molding agent 23 is injected, the casing agent 1 is made easy to flow into the one end side of the terminal portion 12a. Is preferably placed horizontally. Further, the molding agent 23 to be injected is filled so as to completely fill the passage 11a of the spacer 11 at least between the injection passage 21 and the connector 12.

As a result, when the liquid molding agent 23 solidifies in the passage 11a, the solid molding agent 23 in the passage 11a of the spacer 11 becomes dense at least between the injection passage 21 and the connector 12. While being filled, the connecting portion between the terminal portion 12a of the connector 12 and the control line 13 is provided so as to be completely covered and protected by the solidified molding agent 23.

In other words, the mold agent 23 is sufficiently used in the conventional purge port 16 which supplies the purge gas through the flow path such as the wear-prone portion of the protective dry bearing 15 or the gap between the rotor shaft 3 and the electrical component 9. The part where the purge gas cannot be supplied, that is, one end of the terminal portion 12a is completely covered and protected.

Therefore, in the turbo molecular pump of the above-mentioned embodiment, the connecting portion between the one end of the terminal portion and the control wire is covered and protected with the molding agent and completely shielded from corrosive gas. The connection part may be corroded due to insufficient supply of purge gas, or such corrosion may cause contact failure or disconnection between one end of the terminal part and the control wire, which may cause control to adjust the rotor speed or rotor The control for supporting the position is not lost, that is, the uncontrollability of the rotor caused by the corrosive gas can be reliably prevented.

[0030]

[Effect of device]

 In the turbo molecular pump according to the present invention, since the purge port for directly supplying the purge gas such as the inert gas is provided on one end side of the terminal portion as described above, the connecting portion between the one end of the terminal portion and the control line is The high-concentration purge gas is sufficiently supplied and completely shielded from corrosive gas, so that the connection part is corroded due to insufficient supply of purge gas, or such corrosion causes one end of the terminal part and the control wire. There is no possibility that control for adjusting the rotational speed of the rotor or control for supporting the rotor in a fixed position cannot be disabled due to poor contact with or disconnection of the rotor. , The reliability of the turbo molecular pump is improved.

According to the second aspect of the invention, an injection passage communicating with the passage of the spacer is formed on the outer peripheral surface of the spacer, and the injection passage and the passage of the spacer are used for injection and the terminal. Since the molding agent for protecting one end of the section is provided, the connecting portion between the one end of the terminal section and the control line is protected by the molding agent and completely shielded from the corrosive gas, so that the same effect as described above can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a turbo molecular pump according to the present invention.

FIG. 2 is a sectional view showing a second embodiment of the present invention.

FIG. 3 is a sectional view showing an essential part of a third embodiment of the present invention.

FIG. 4 is a sectional view showing an essential part of a third embodiment of the present invention.

FIG. 5 is a sectional view of a conventional turbo molecular pump.

[Explanation of symbols]

 1 Casing 2 Rotor 4 Rotor Blade 5 Stator Blade 9 Electrical Parts 11 Spacer 12 Connector 12a Terminal 13 Control Line 20 Purge Port 21 Injection Path 23 Molding Agent

Claims (2)

[Scope of utility model registration request] 1. A rotor rotatably arranged inside a casing, a rotor blade attached to an outer peripheral surface of the rotor, a stator blade attached to an inner wall surface of the casing, and a rotor blade installed inside the casing. And a drive motor for rotating the rotor around its axis or an electric component such as a magnetic bearing for supporting the rotor in a fixed position by magnetic force,
A spacer having a passage formed therein, one end of which communicates with the inside of the casing and the other end of which communicates with the outside of the casing, and the spacer is attached to the casing through the spacer and has one end exposed in the passage of the spacer and the other end of the casing. A connector having a terminal portion provided so as to be exposed to the outside of the vehicle, and the electric component and the control unit provided outside the casing are connected through the terminal portion, and the control unit controls the electric component. A turbo molecular pump having a control line for controlling the turbo molecular pump, wherein a purge port for directly supplying a purge gas such as an inert gas is provided on one end side of the terminal portion. 2. A rotor rotatably disposed inside a casing, rotor blades mounted on an outer peripheral surface of the rotor, stator blades mounted on an inner wall surface of the casing, and a rotor blade mounted inside the casing. And a drive motor for rotating the rotor around its axis or an electric component such as a magnetic bearing for supporting the rotor in a fixed position by magnetic force,
A spacer having a passage formed therein, one end of which communicates with the inside of the casing and the other end of which communicates with the outside of the casing, and the spacer is attached to the casing through the spacer and has one end exposed in the passage of the spacer and the other end of the casing. A connector having a terminal portion provided so as to be exposed to the outside of the vehicle, and the electric component and the control unit provided outside the casing are connected through the terminal portion, and the control unit controls the electric component. In the turbo-molecular pump having a control line, the injection passage communicating with the passage of the spacer is formed on the outer peripheral surface of the spacer, and the injection is made through the injection passage and the passage of the spacer and one end of the terminal portion A turbo molecular pump characterized by being provided with a molding agent for protecting the above.