CN108708863B

CN108708863B - Vacuum pump, rotary body and stationary vane of vacuum pump, and method for manufacturing same

Info

Publication number: CN108708863B
Application number: CN201711103957.9A
Authority: CN
Inventors: 大立好伸; 前岛靖; 高阿田勉
Original assignee: Edwards Japan Ltd
Current assignee: Edwards Japan Ltd
Priority date: 2016-11-24
Filing date: 2017-11-10
Publication date: 2022-05-13
Anticipated expiration: 2037-11-10
Also published as: CN114370410A; CN108708863A; JP2018084191A; JP6981748B2

Abstract

The invention provides a vacuum pump, a rotary body and a stationary blade of the vacuum pump, and a manufacturing method thereof, which are suitable for avoiding the high temperature of parts which do not need to be increased, such as electric components for controlling the driving of the rotary body, and efficiently increasing the temperature of the parts which need to be increased in the vacuum pump, such as a thread groove pump stator, so as to reduce the accumulation of reaction products. The rotating body (4) is provided with a1 st cylinder body (4A) constituting a thread groove pump mechanism portion and a2 nd cylinder body (4B) constituting a turbo molecular pump mechanism portion, and is configured such that a plurality of moving blades (6) are arranged in multiple stages on the outer peripheral surface of the 2 nd cylinder body (4B), and is configured such that a low emissivity portion having an emissivity smaller than that of the outer surfaces of the moving blades (6) is formed by at least a part of a cylinder inner surface constituted by an inner surface (S1) of the 1 st cylinder body (4A) and an inner surface (S2) of the 2 nd cylinder body (4B), and an outer surface (Q1) of the 1 st cylinder body (4A).

Description

Vacuum pump, rotary body and stationary vane of vacuum pump, and method for manufacturing same

Technical Field

The present invention relates to a vacuum pump, a rotary body and a stationary blade of the vacuum pump, and a method for manufacturing the same, which are used as a gas exhaust mechanism for a processing chamber, other sealed chambers, and the like in a semiconductor manufacturing apparatus, a flat panel display manufacturing apparatus, and a solar cell panel manufacturing apparatus.

Background

Conventionally, as such a vacuum pump, for example, a vacuum pump described in patent document 1 or patent document 2 is known. Referring to fig. 3 c of patent document 1, in the conventional vacuum pump described in patent document 1, the upper surface of one rotor blade (12) is configured as a high emissivity portion (high emissivity region), and the rotor blade (12) is specifically the lowermost rotor blade (12), while the lower surface of the same rotor blade (lowermost rotor blade) is configured as a low emissivity portion (low emissivity region). This is because the temperature of the screw-groove pump stator (cylindrical stator 22) can be easily increased by reducing the heat radiation from the screw-groove pump stator (cylindrical stator 22) to the lowermost rotor blade (12), and the deposition of the reaction product in the screw-groove pump stator (cylindrical stator 22) can be reduced.

However, in order to obtain the rotor blade (12) having the high emissivity portion and the low emissivity portion as described above, for example, when the high emissivity portion is provided by a chemical solution, the lower surface (low emissivity portion) of the rotor blade at the lowest stage needs to be shielded by a shielding member in order to protect the low emissivity portion (the lower surface of the rotor blade (12) at the lowest stage) from the chemical solution.

However, according to the vacuum pump described in patent document 1, it is difficult to shield the lower surface (low emissivity portion) of the lowermost rotor blade (12) with the shielding member in the structure of the rotor blade (12) as described above, and there is a problem due to a shielding failure, that is, it is desirable that the original range of the low emissivity portion (the lower surface of the lowermost rotor blade (12)) is locally configured as an undesirable high emissivity portion. In this case, since heat is easily transferred from the screw-groove pump stator (cylindrical stator 22) toward the lowermost-stage rotor blade (12) via the undesirably high emissivity portion, it is difficult to increase the temperature of the screw-groove pump stator (cylindrical stator 22), which is a portion where it is desired to reduce the deposition of the reaction product by local increase in temperature, and there is a problem that the deposition of the reaction product in the screw-groove pump stator cannot be sufficiently reduced.

Patent document 1 does not disclose or suggest how much the inner surface of the rotating body (pump rotor 10) has emissivity. When the emissivity of the inner surface of the rotating body (pump rotor 10) is high, the heat of the rotating body (pump rotor 10) is radiated to the components inside the rotating body (pump rotor 10), and it is more difficult to increase the temperature of the screw groove pump stator, that is, the portion that needs to be increased in temperature, and the electric components inside the rotating body (pump rotor 10), such as the magnetic bearings that support the rotating body, the motor that drives the rotating body, and the like, are heated, and it is also assumed that malfunctions such as malfunctions of the electric components, pump failures, and the like occur.

Patent document 1: japanese patent laid-open publication No. 2015-229949.

Patent document 2: japanese patent laid-open No. 2005-320905.

Disclosure of Invention

The present invention has been made in view of the above circumstances, and an object thereof is to provide a vacuum pump, a rotary body and a stationary blade of the vacuum pump, and a method for manufacturing the same, which are suitable for avoiding the temperature increase of a portion which does not require the temperature increase, such as an electric component for controlling the driving of the rotary body, and efficiently increasing the temperature of a portion which requires the temperature increase in the vacuum pump, such as a screw groove pump stator, thereby reducing the accumulation of reaction products.

In order to achieve the above object, the present invention provides a vacuum pump according to 1 st aspect of the present invention which sucks and exhausts gas by rotation of a rotating body, wherein the rotating body includes a1 st cylindrical body constituting a thread groove pump mechanism portion and a2 nd cylindrical body constituting a turbo molecule pump mechanism portion, a plurality of vanes are arranged in multiple stages on an outer peripheral surface of the 2 nd cylindrical body, and at least a part of a cylindrical inner surface constituted by an inner surface of the 1 st cylindrical body and an inner surface of the 2 nd cylindrical body and an outer surface of the 1 st cylindrical body constitute a low emissivity portion having an emissivity smaller than an emissivity of an outer surface of the vanes.

In the above-described invention of claim 1, the following features may be provided: an intermediate portion is provided between the low emissivity portion and a high emissivity portion provided adjacent to the low emissivity portion, and the intermediate portion has an emissivity greater than that of the low emissivity portion and smaller than that of the high emissivity portion.

In the above-described invention of claim 1, the following features may be provided: the intermediate portion is located in one of the design ranges of the high emissivity portion and the low emissivity portion, and the other design range is constituted only by the high emissivity portion or the low emissivity portion excluding the intermediate portion.

In the above-described invention of claim 1, the following features may be provided: the inner surface of the 2 nd cylindrical body is configured as a high emissivity portion having a higher emissivity than the low emissivity portion.

In the invention of claim 1, the following may be used: the end surface of the 1 st cylindrical body is configured as a high emissivity portion having a higher emissivity than the low emissivity portion.

In the above-described invention of claim 1, the following features may be provided: the end surface of the 1 st cylindrical body is configured as a low emissivity portion having a lower emissivity than the high emissivity portion.

In the above-described invention of claim 1, the following features may be provided: the surface of the lowermost rotor blade among the rotor blades is configured as the low emissivity portion.

In the above-described invention of claim 1, the following features may be provided: the low emissivity portion is formed on a surface of the rotor at the lowermost stage of the rotors, the surface facing a fixing member of the screw pump mechanism.

In the invention of claim 1, the following may be used: a shielding member is disposed between the lowermost rotor among the rotors and a fixing member of the screw pump mechanism, and the low emissivity portion is formed in the shielding member.

In the above-described invention of claim 1, the following features may be provided: and a stationary blade provided between the rotor blades in the pump axial direction among the rotor blades, the stationary blade including an outer rim for being supported on an outer peripheral portion of the outer rim and/or in the vicinity of the outer peripheral portion, at least one of an upper surface and a lower surface of the outer rim and an outer peripheral surface constituting the low emissivity portion.

In the above-described invention of claim 1, the following features may be provided: and a stationary blade provided between the rotor blades in a pump axial direction among the rotor blades, the stationary blade including an outer rim supported at an outer peripheral portion of the outer rim and/or in a vicinity of the outer peripheral portion, the outer rim being formed in an annular shape as a whole by abutting and joining a plurality of rim members, and an abutting surface of the rim members constituting the low emissivity portion.

In the above-described invention of claim 1, the following features may be provided: the low emissivity unit is formed of a multilayer structure in which a1 st low emissivity unit and a2 nd low emissivity unit are stacked.

The present invention 2 is a method for manufacturing a rotating body of a vacuum pump including a1 st cylindrical body constituting a screw groove pump mechanism portion and a2 nd cylindrical body constituting a turbo molecular pump mechanism portion, a plurality of vanes being arranged in multiple stages on an outer peripheral surface of the 2 nd cylindrical body, the method comprising: a protection step of protecting at least a part of a cylindrical inner surface formed by an inner surface of the 1 st cylindrical body and an inner surface of the 2 nd cylindrical body and/or an outer surface of the 1 st cylindrical body so as not to be subjected to high emissivity surface treatment; and a surface treatment step of performing the high emissivity surface treatment on the rotating body after the protection step.

In the invention of claim 2, the following may be used: the rotating body includes a through hole for fastening the 1 st cylindrical body or the 2 nd cylindrical body to a rotating shaft, and the protecting step includes a process of sealing the through hole.

In the invention of claim 2, the following may be used: a fastening step of fastening the rotating body including a plurality of through holes for fastening the 1 st cylindrical body or the 2 nd cylindrical body to the rotating shaft, the fastening step being performed before the protection step, the fastening step including: the method for protecting a cylindrical member according to the present invention is characterized in that the 2 nd cylindrical member is fastened to the rotary shaft by inserting a distal end of the rotary shaft into one of the through holes located on a rotation center line of the rotary body from an inner surface side of the rotary body, and then inserting a fastening bolt into the other through hole to fasten the distal end to the rotary shaft, and the protecting step includes a step of attaching a protective cover to a distal end portion of the rotary shaft inserted in the fastening step.

In the invention of claim 2, the following may be used: the protective cover has a function of preventing the high emissivity surface treatment from being performed toward the inner surface side of the rotating body through the gap between the fastening bolt and the through hole, and a function of preventing corrosive substances of the rotating shaft and the fastening bolt from flowing out of the vacuum pump due to corrosive gas.

The present invention is a method for manufacturing a rotating body of a vacuum pump including a1 st cylindrical body constituting a thread groove pump mechanism portion and a2 nd cylindrical body constituting a turbo molecular pump mechanism portion, wherein a plurality of vanes are arranged in multiple stages on an outer peripheral surface of the 2 nd cylindrical body, and a through hole for fastening the 1 st cylindrical body or the 2 nd cylindrical body to a rotating shaft is provided, the method for manufacturing a rotating body of a vacuum pump being characterized in that the through hole is processed after a high emissivity surface treatment is performed on an outer surface of the rotating body.

In the above 2 nd and 3 rd inventions, the following may be featured: the outer rim of the stationary blade provided between the moving blades is formed in an annular shape as a whole by butting and joining a plurality of rim members, and the high emissivity surface treatment is applied to the stationary blade in a state where the rim members are butted and joined, so that the butting surfaces of the rim members are in a state of having a lower emissivity than the high emissivity portions formed on the surfaces of the stationary blade by the high emissivity surface treatment.

In the above 2 nd and 3 rd inventions, the following may be featured: when the high emissivity surface treatment is performed, the outer surface of the 1 st cylindrical body is protected by an acid-resistant shielding member.

In the above 2 nd and 3 rd inventions, the following may be featured: the protection step includes a step of protecting the substrate with an acid-resistant shielding member.

In the above 2 nd and 3 rd inventions, the following may be featured: the shielding member is a rubber material containing fluorine.

The present invention 4 is a method for manufacturing a rotating body of a vacuum pump including a1 st cylindrical body constituting a screw groove pump mechanism portion and a2 nd cylindrical body constituting a turbo molecular pump mechanism portion, a plurality of vanes being arranged in multiple stages on an outer peripheral surface of the 2 nd cylindrical body, the method comprising: a1 st surface treatment step of performing a low emissivity surface treatment on at least a portion of the entire outer peripheral surface of the rotating body, the portion being desired to be a low emissivity portion; a masking step of masking a low emissivity surface layer formed by the low emissivity surface treatment in the 1 st surface treatment step, in a portion desired to be configured as the low emissivity portion; and a2 nd surface treatment step of performing a high emissivity surface treatment on the entire rotating body masked by the masking step.

In the 4 th invention, the following may be characterized: the first surface treatment step 1 is a step of: preparing a treatment bath filled with a low emissivity surface treatment liquid, and immersing in the treatment bath a portion of the entire outer peripheral surface of the rotating body, which is at least desired to be the low emissivity portion, to perform the low emissivity surface treatment on the portion, wherein the 2 nd surface treatment step is a step of: a treatment tank filled with a high emissivity surface treatment liquid is prepared, and the entire rotating body masked by the masking step is immersed in the treatment tank, thereby performing the high emissivity surface treatment on the rotating body.

In the 4 th invention, the following may be characterized: the shielding member has elasticity capable of deforming in accordance with the shape of the irregularities caused by the surface roughness of the shielding surface.

Another aspect of the present invention is a rotor characterized by being used in the vacuum pump or a stator characterized by being used in the vacuum pump.

According to the present invention, as described above, at least a part of the cylindrical inner surface of the rotating body is configured as the low emissivity portion having a lower emissivity than the outer surface of the rotor blade. Therefore, it is possible to provide a vacuum pump which can reduce the amount of heat radiated from a portion, which is a member located outside the rotating body, to the outer surface of the rotating body, and which particularly requires a high temperature in the vacuum pump, such as a screw groove pump stator, and which can efficiently increase the temperature of the portion requiring a high temperature, and which is suitable for reducing the deposition of reaction products by increasing the temperature of the portion.

In the present invention, as described above, the amount of heat radiated from the rotating body to the inside thereof is reduced, so that it is possible to maintain a relatively low temperature in a portion where it is desired to avoid a high temperature, such as an electric component (for example, a magnetic bearing that supports the rotating body, a motor that rotationally drives the rotating body, or the like) located inside the rotating body, and it is also possible to effectively reduce an erroneous operation, a pump failure, or the like due to overheating of the electric component.

Further, in the present invention in which the protection step is adopted, when the high emissivity surface treatment is applied to the outer surface of the rotating body, the inner surface of the rotating body can be protected from the high emissivity surface treatment, and the inner surface of the rotating body can be configured as the low emissivity portion, so that the above-described operational effect, that is, the operational effect of efficiently raising the temperature of the portion which is a member located outside the rotating body and which particularly needs to be raised in the vacuum pump, can be obtained as well.

Drawings

Fig. 1 is a sectional view of a vacuum pump to which the present invention is applied.

Fig. 2 is an explanatory view of a range of a low emissivity portion and a high emissivity portion in a rotating body constituting the vacuum pump of fig. 1.

Fig. 3 is an explanatory view of a process (example 1) for obtaining a high emissivity part by plating treatment.

Fig. 4 is an explanatory view of a process (example 2) for obtaining a high emissivity part by plating treatment.

Fig. 5 is an explanatory view of a process (example 3) for obtaining a high emissivity part by plating treatment.

Fig. 6 is an explanatory diagram of a structure (boundary structure) in the vicinity of a boundary between the low emissivity portion and the high emissivity portion.

Fig. 7 is an explanatory diagram of an example in which the surface of the lowermost rotor blade is configured as a low emissivity portion.

Fig. 8 is an explanatory diagram of an example of a member interposed as a heat insulating member having a low emissivity portion between the lowermost movable wing and the fixed member facing the lowermost movable wing.

Fig. 9 is an explanatory diagram of an example in which at least one of the upper and lower surfaces and the outer peripheral surface of the outer rim is configured as a low emissivity portion.

Fig. 10 is an explanatory diagram of an example in which the abutting surfaces of the plurality of rim members are configured as the low emissivity portions.

Fig. 11 is an explanatory diagram of an example in which the high emissivity portion is the uppermost layer of the multilayer structure.

Fig. 12 is an explanatory diagram of surface roughness in the shielding member and the shielded surface.

Fig. 13 is an explanatory view of a state in which the shielding member having elasticity is attached to the shielded surface.

Detailed Description

The best mode for carrying out the present invention will be described in detail below with reference to the attached drawings.

Fig. 1 is a sectional view of a vacuum pump to which the present invention is applied, and fig. 2 is an explanatory view of a range of a low emissivity part and a high emissivity part in a rotating body constituting the vacuum pump P of fig. 1.

The vacuum pump P shown in fig. 1 is a compound pump including a turbo-molecular mechanism Pt and a screw groove pump mechanism Ps as a gas exhaust mechanism, and is used, for example, as a gas exhaust mechanism of a process chamber or other closed chamber in a semiconductor manufacturing apparatus, a flat panel display manufacturing apparatus, or a solar cell panel manufacturing apparatus.

In the vacuum pump P of fig. 1, the outer package 1 is formed into a bottomed substantially cylindrical shape by integrally coupling a cylindrical pump housing C and a pump base B in the direction of the cylinder axis thereof by a fastening member.

The upper end portion side (upper side in fig. 1) of the pump casing C is opened as a gas inlet port 1A, and a gas outlet port 2 is provided in the pump base B. The gas inlet port 1A is connected to a closed chamber, not shown, which is a high vacuum chamber, such as a process chamber of a semiconductor manufacturing apparatus, for example, and the gas outlet port 2 is connected to an auxiliary pump, not shown, in communication therewith.

A cylindrical stator column 3 is provided in the center of the pump housing C. The stator column 3 is erected on the pump base B, the rotating body 4 is provided on the outside of the stator column 3, and various electrical components such as a magnetic bearing MB as a mechanism for supporting the rotating body 4 in the radial and axial directions and a drive motor MT as a mechanism for rotationally driving the rotating body 4 are incorporated inside the stator column 3. Since the magnetic bearings MB and the drive motor MT are well known, detailed descriptions of the specific configurations thereof will be omitted.

The rotor 4 is rotatably disposed on the pump base B, and is covered by the pump base B and the pump casing C.

The rotor 4 has a substantially cylindrical shape surrounding the outer periphery of the stator pole 3, and has a structure in which two cylindrical bodies (in the vacuum pump P of fig. 1, the 1 st cylindrical body 4A constituting the screw groove pump mechanism portion Ps and the 2 nd cylindrical body 4B constituting the turbo molecular pump mechanism portion Pt) having different diameters are coupled in the cylindrical axial direction thereof by the coupling portion 4C, a structure in which a fastening coupling portion 4D for fastening the 2 nd cylindrical body 4B to a rotation shaft 4 described later is provided on the inner surface of the 2 nd cylindrical body 4B, and a structure in which a plurality of rotor blades 6 described later are arranged in multiple stages on the outer peripheral surface of the 2 nd cylindrical body 4B.

A rotary shaft 41 is provided inside the rotary body 4, and the rotary shaft 41 is integrally fastened and coupled to the 2 nd cylinder body 4B via a fastening and coupling portion 4D. As a specific fastening structure of the rotary shaft 41, in the vacuum pump P of fig. 1, the fastening portion 4D is provided with a plurality of through holes H1, H2 (see fig. 2) for fastening and fastening the 2 nd cylindrical body 4B to the rotary shaft 41.

Then, the distal end of the rotating shaft 41 is press-fitted into a through hole (hereinafter referred to as "central through hole H1") located on the rotation center line of the rotating body 4 among the plurality of through holes H1 and H2 from the inner surface side of the rotating body 4, and then the fastening bolt BT is inserted and fastened to another through hole (hereinafter referred to as "peripheral through hole H2") located around the central through hole H1, thereby fastening and fastening the 2 nd cylindrical body 4B integrally with the rotating shaft 41.

The assembly by inserting the rotary shaft 41 into the through hole H1 as described above is not limited to the press fitting described above, and may be a structure of a thermal press fit, an assembly by a shrink fit, or a clearance fit.

In the vacuum pump P of fig. 1, the rotary shaft 41 is supported by the magnetic bearings MB built in the stator post 3, and the rotary shaft 41 is rotationally driven by the drive motor MT built in the stator post 3, so that the rotary body 4 rotates around the rotational center (the center of the rotary shaft 41) while being supported by magnetic force at a predetermined position in the axial direction and the radial direction. In this structure, the rotary shaft 41, the magnetic bearings MB, and the drive motor MT function as a support and drive mechanism for the rotary body 4. The rotary body 4 may be supported and rotationally driven around its axial center by another structure different from this.

The vacuum pump P shown in fig. 1 includes gas passages R1 and R2 as means for sucking gas from the gas inlet port 1A by rotation of the rotary body 4 about the rotary shaft 41 and discharging the sucked gas to the outside from the gas outlet port 2.

As an embodiment of the gas flow paths R1 and R2, in the vacuum pump P of fig. 1, the gas flow path R1 on the front half (on the upstream side of the coupling portion 4C of the rotor 4) in the entire gas flow paths R1 and R2 is formed by a plurality of moving blades 6 provided on the outer peripheral surface of the rotor 4 and a plurality of stationary blades 7 fixed to the inner peripheral surface of the pump housing C via spacers 9, and the exhaust gas flow path R2 on the rear half (on the downstream side of the coupling portion 4C of the rotor 4) is formed as a flow path in a thread groove shape by the outer peripheral surface of the rotor 4 (specifically, the outer peripheral surface of the first cylindrical body 4A) and the thread groove pump stator 8 facing thereto.

Describing the configuration of the suction-side gas flow path R1 in more detail, in the vacuum pump P of fig. 1, a plurality of the rotor blades 6 constituting the suction-side gas flow path R1 are arranged radially about the pump axial center (for example, the rotation center of the rotor 4). On the other hand, the stationary blades 7 constituting the suction-side gas flow path R1 are disposed and fixed to the inner peripheral side of the pump casing C via spacers 9 so as to be positioned in the pump radial direction and the pump axial direction, and are disposed in a plurality of rows radially centered on the pump axial center.

In the vacuum pump P of fig. 1, the suction-side gas flow path R1 is formed by alternately arranging the moving blades 6 and the stationary blades 7, which are arranged radially as described above, in a plurality of stages in the pump axial direction.

In the intake-side gas flow path R1 configured as described above, the rotor 4 and the plurality of rotor blades 6 are integrally rotated at high speed by starting the drive motor MT, and the rotor blades 6 impart a downward movement to the gas molecules entering from the gas intake port 1A. Then, the gas molecules having such a downward movement amount are sent to the rotor side of the next stage by the stationary blades 7. By repeating the above-described imparting of the movement amount and the feeding operation to the gas molecules in multiple stages, the gas molecules on the gas intake port side are exhausted so as to sequentially travel in the direction of the exhaust gas flow passage R2 through the intake gas flow passage R1.

Next, describing the configuration of the exhaust-side gas flow passage R2 in more detail, in the vacuum pump P of fig. 1, the screw groove pump stator 8 constituting the exhaust-side gas flow passage R2 is an annular fixed member surrounding the downstream-side outer peripheral surface of the rotating body 4 (specifically, the outer peripheral surface of the 1 st cylindrical body 4A, the same applies hereinafter), and is disposed so that its inner peripheral surface side faces the downstream-side outer peripheral surface of the rotating body 4 (specifically, the outer peripheral surface of the 1 st cylindrical body 4A) with a predetermined gap.

Further, a thread groove 8A is formed in the inner peripheral portion of the thread groove pump stator 8, and the thread groove 8A changes in a conical shape in which the depth thereof decreases downward, and is engraved in a spiral shape from the upper end to the lower end of the thread groove pump stator 8.

In the vacuum pump P of fig. 1, the exhaust-side gas flow path R2 is formed as a screw-groove-shaped gas flow path by facing the downstream-side outer peripheral surface of the rotary body 4 to the screw-groove pump stator 8 having the screw grooves 8A. As another embodiment to be distinguished from this, although not shown, for example, the exhaust side gas flow path R2 may be formed by providing the thread groove 8A on the outer peripheral surface on the downstream side of the rotary body 4.

In the exhaust-side gas flow path R2 configured as described above, when the rotary body 4 is rotated by starting the drive motor MT, gas flows in from the intake-side gas flow path R1, and the gas flowing in is exhausted while being compressed from the transition flow into the viscous flow and transferred by utilizing the effect of the drag (ドラッグ) between the thread groove 8A and the downstream-side outer peripheral surface of the rotary body 4.

Referring to fig. 2, in the vacuum pump P of fig. 1, at least a part of the inner surface of the rotating body 4 (the entire inner surface S1 and the inner surface S2 in the example of fig. 2) and the outer surface Q1 of the 1 st cylindrical body 4A are each configured as a low emissivity portion EM1 having a lower emissivity than the outer surface of the rotor blade 6, and the inner surface of the rotating body 4 is specifically a cylindrical inner surface configured by the inner surface S1 of the 1 st cylindrical body 4A and the inner surface S2 of the 2 nd cylindrical body 4B. In the present embodiment, the inner surface S3 of the fastening and connecting portion 4D is also configured as a low emissivity portion EM1 having a lower emissivity than the outer surface of the rotor blade 6.

According to the vacuum pump P of fig. 1, as described above, at least a part of the cylindrical inner surface of the rotating body 4 is configured as the low emissivity portion EM 1. Therefore, the amount of heat radiated from the outer surface of the rotary body 4 from the portion of the vacuum pump P that particularly needs to be heated, such as the screw-groove pump stator 8, is reduced, and the portion that needs to be heated can be efficiently heated.

In addition, according to the vacuum pump P of fig. 1, since the amount of heat radiated from the rotating body 4 to the inside is reduced as described above, it is possible to maintain a relatively low temperature of a portion that is located inside the rotating body 4 and is expected to avoid a high temperature, such as electric components (for example, the magnetic bearing MB that supports the rotating body 4, the motor MT that rotationally drives the rotating body 4, and the like), and it is also possible to effectively reduce an erroneous operation due to overheating of the electric components and a pump failure.

The low emissivity portion EM1 includes a portion obtained without performing any surface treatment (for example, plating treatment) for changing the emissivity of heat, that is, a portion (non-plating type) having the original emissivity of the material constituting the 1 st or 2 nd

cylindrical members

4A and 4B or the fastening connection portion 4D, and a portion (plating type) having the emissivity of a low emissivity plating layer formed by plating treatment such as nickel alloy plating.

The low emissivity portion EM1 may have a multilayer structure in which a2 nd low emissivity portion is stacked on a1 st low emissivity portion. The low emissivity portion having such a multilayer structure can be obtained by, for example, forming a base layer (1 st low emissivity portion) by performing a nickel alloy plating treatment on the surface to be plated, and providing a nickel alloy plating layer (2 nd low emissivity portion) by performing a nickel alloy plating treatment on the base layer.

The portion other than the low emissivity portion EM1 described above is configured to include a high emissivity portion EM2 having a higher emissivity than the low emissivity portion EM1 in the entire surface of the rotor 4, and the portion other than the low emissivity portion EM1 described above is, for example, the outer surface Q2 of the 2 nd cylindrical body 4B and the outer surface Q3 of the rotor blade 6. Such a high emissivity portion EM2 can be obtained by, for example, high emissivity surface treatment with a high emissivity coating liquid.

The surface can be formed by immersing the rotating body 4 in an acid to oxidize the surface.

For the high emissivity portion EM2, for example, nickel oxide plating can be used. Here, when the heat dissipation properties of electroless plating, nickel alloy plating, and nickel oxide plating are compared, the magnitude relationship of the heat dissipation properties is as follows.

Size relationship of seed and heat dissipation

Nickel oxide coating > nickel alloy coating > no coating (base material)

The reason why the outer surface Q2 of the cylindrical body 2B and the outer surface Q3 of the rotor blade 6 are configured as the high emissivity portion EM2 as described above is to improve heat dissipation from the rotor 4 toward the outer package 1, thereby reducing thermal expansion deformation and creep rupture of the rotor blade 6.

[ description of method 1 for manufacturing rotating body 4 ]

Fig. 3 is an explanatory view of a first manufacturing method of a rotating body constituting the vacuum pump of fig. 1.

As the first manufacturing method of the rotor 4 including the low emissivity portion EM1 and the high emissivity portion EM2, the rotor 4 can be manufactured by performing a protection step and a surface treatment step, which will be described later, after the machining (for example, forming the rotor blades 6 by cutting) is completed.

The protection process is as follows: the portion desirably configured as the low emissivity portion EM1 (specifically, at least a portion of the cylindrical inner surface configured by the inner surface S1 of the 1 st cylindrical body 4A and the inner surface S2 of the 2 nd cylindrical body 4B, and the outer surface Q1 of the 1 st cylindrical body 4A) is protected from the high emissivity surface treatment.

The surface treatment step is a step of: after the protection step, the rotating body 4 is subjected to a high emissivity surface treatment.

In the protection step, as shown in fig. 3, a portion which is desired to be configured as the low emissivity portion ME1 (see fig. 2) may be protected by a shielding member MSK1 or a shielding jig (not shown).

The shield member MSK1 prevents the high emissivity surface treatment from being applied to the outer surface Q1 of the 1 st cylindrical body 4A which is desired to be configured as the low emissivity portion ME1, and also prevents the high emissivity surface treatment from being applied to the cylindrical inner surface which is desired to be configured as the low emissivity portion ME1 and which is configured by the inner surface S1 of the 1 st cylindrical body 4A and the inner surface S2 of the 2 nd cylindrical body 4B by closing the lower end opening of the 1 st cylindrical body 4A.

The protection step includes a process of indirectly closing the upper end opening of the 2 nd cylindrical body 4B by a shielding member MSK2 or a shielding jig (not shown) to thereby indirectly close the plurality of through holes (H1, H2) (hereinafter, referred to as "through hole closing process") as shown in fig. 3.

The through-hole sealing treatment prevents the high emissivity surface treatment from being applied to the portion desired to be the low emissivity portion ME1, specifically, the portion desired to be the low emissivity portion ME1, which is the cylindrical inner surface formed by the inner surface S1 of the 1 st cylindrical body 4A and the inner surface S2 of the 2 nd cylindrical body 4B.

In the surface treatment step, the entire rotary body 4 is immersed in the plating tank PB filled with the high-emissivity plating solution or the acidic solution, thereby performing the high-emissivity surface treatment on the outer surface of the rotary body 4 except for the shielding treatment performing portion.

[ description of method 2 for manufacturing rotating body 4 ]

Fig. 4 is an explanatory view of a2 nd manufacturing method of a rotating body constituting the vacuum pump of fig. 1.

The manufacturing method 2 is the same as the manufacturing method 1 except that the through-hole plugging process in the protection step is different from the manufacturing method 1 described above, and thus detailed description thereof is omitted.

Referring to fig. 4, in the through-hole sealing process in the protection step in the manufacturing method 2, one or both ends of the through-holes (H1, H2) are sealed by the LID member LID, so that all of the plurality of through-holes (H1, H2) are directly sealed. The difference from the protection process of fig. 3 is that a part of the upper end opening of the rotor 4 is not protected, and the LID member LID can be fixed using the conventional through holes (H1, H2).

[ description of method 3 for manufacturing rotating body 4 ]

Fig. 5 is an explanatory view of a 3 rd manufacturing method of a rotating body constituting the vacuum pump of fig. 1.

As the 3 rd manufacturing method of the rotor 4 including the low emissivity portion EM1 and the high emissivity portion EM2, the rotor 4 can be manufactured by sequentially providing a fastening step, a protecting step, and a plating step after the completion of the machining.

In the above-described manufacturing method 1 or 2, the high emissivity surface treatment is performed on the outer surface of the rotating body 4 before the rotating shaft 41 is attached to the rotating body 4. In contrast, referring to fig. 5, in the 3 rd manufacturing method, in a state where the 2 nd cylindrical body 4B is fastened to the rotary shaft 41, that is, in a state where the rotary shaft 41 is attached to the rotary body 4, the entire rotary body 4 is immersed in the plating tank PB filled with the high-emissivity plating liquid or the acidic solution, and the rotary body 4 is subjected to the high-emissivity surface treatment.

In the fastening step in the manufacturing method 3, the distal end of the rotating shaft 41 is pressed into the center through hole H1 of the plurality of through holes (H1, H2) from the inner surface side of the rotating body 4, and then the fastening bolt BT is inserted into the peripheral through hole H2 and fastened, thereby fastening the 2 nd cylindrical body 4B to the rotating shaft 41.

A part of the protection step in the 3 rd manufacturing method is different from the protection step in the 1 st manufacturing method described above, and specifically, the through-hole plugging process is a part of the protection step. That is, referring to fig. 5, in the protection step in the manufacturing method 3, as an example of the through-hole sealing process, the inner surface of the rotating body 4 is protected from the high emissivity surface treatment by attaching the protective cover PC to the distal end portion of the rotating shaft 41 which is press-fitted in through the fastening step.

Note that the plating step in the 3 rd manufacturing method is the same as the plating step in the 1 st manufacturing method, and therefore, detailed description thereof is omitted.

However, the protective cover PC attached as described above functions as a means for preventing the inner surface of the rotary body 4 from being surface-treated with high emissivity through the gaps between the through holes (H1, H2) and the fastening bolts BT. The protective cover PC attached as described above is not detached after the vacuum pump P is assembled, but is present as a vacuum pump component, and functions as a mechanism for preventing corrosion of the rotating shaft 41 and the fastening bolt BT caused by corrosive gas, and preventing corrosive substances from flowing out of the vacuum pump P even when corroded.

[ 4 th method for manufacturing rotating body 4 ]

In the above-described production methods 1 to 3, the rotary 4 is immersed in a plating bath filled with a high-emissivity plating solution or an acidic solution in a state where a plurality of through-holes (H1, H2) have been formed in the rotary 4, thereby performing a high-emissivity surface treatment on the outer surface of the rotary 4. In contrast, in the 4 th manufacturing method, after the high emissivity surface treatment is performed, a plurality of through holes (H1, H2) are processed (formed).

Therefore, according to the 4 th production method, since a plurality of through holes (H1, H2) are not present at the stage of performing the high emissivity surface treatment, a process (through hole plugging process) of plugging the through holes (H1, H2) at the time of the high emissivity surface treatment is not necessary.

[ description of method 5 for manufacturing rotating body 4 ]

In the case where the outer surface Q1 of the 1 st cylindrical body 4A in the rotating body 4 is configured as the plating-type low emissivity portion EM1, the plating-type low emissivity portion EM1 is formed as a low emissivity plating layer formed by plating treatment such as nickel alloy plating, for example.

On the other hand, on the outer surface of the rotating body 4 configured as the high emissivity portion EM2, such as the outer surface Q2 of the 2 nd cylindrical body 4B and the outer surface Q3 of the rotor blade 6, for example, nickel oxide is provided as the high emissivity portion EM 2.

Therefore, in order to manufacture the rotating body 4 including the low emissivity portion EM1 and the high emissivity portion EM2 as described above, a so-called partial plating process for forming a low emissivity plating layer and a high emissivity layer is performed. As a specific mode of the partial plating treatment, the following [ partial plating treatment (1) and [ partial plating treatment (2) ] are considered.

[ partial plating (1 thereof) ]

The partial plating treatment (1) is composed of 4 steps of (1-1) the 1 st masking step, (1-2) the 1 st plating step, (1-3) the 2 nd masking step, and (1-4) the 2 nd plating step, described below.

(1-1) the 1 st Shielding step

In the 1 st shielding step, a portion of the entire outer surface of the rotating body 4, which is desired to be configured as the low emissivity portion EM1, is shielded and protected by the 1 st shielding member.

(1-2) the 1 st plating step (1 st surface treatment step)

In the 1 st plating step, a plating tank filled with a low-emissivity plating liquid is prepared as a treatment tank filled with a low-emissivity surface treatment liquid, and the entire rotating body 4 masked in the 1 st masking step is immersed in the plating tank (treatment tank), whereby a low-emissivity surface treatment (plating treatment in this example) is performed only on a portion desired to be configured as a low-emissivity portion EM 1. After that, the 1 st shielding member is removed from the rotating body 4.

(1-3) the 2 nd Shielding step

In the 2 nd masking step, the low emissivity surface treatment layer formed by the low emissivity surface treatment in the 1 st plating step (in this example, the low emissivity coating layer formed by the aforementioned plating step) is masked and protected by the 2 nd masking member.

(1-4) the 2 nd plating treatment step (the 2 nd surface treatment step)

In the 2 nd plating treatment step, a plating tank filled with a high-low emissivity plating liquid is prepared as a treatment tank filled with a high-emissivity surface treatment liquid, and the entire rotating body 4 shielded in the 2 nd shielding step is immersed in the plating tank (treatment tank), that is, the entire rotating body 4 shielded in the 2 nd shielding step is subjected to a high-emissivity surface treatment, whereby a high-emissivity surface treatment is performed on a portion (other than the shielding treatment execution portion) desired to be constituted as the high-emissivity portion EM 2. After that, the 2 nd masking member is removed.

Here, the plating treatment is used to form the low emissivity portion EM1 or the high emissivity portion EM2, but the present invention is not limited thereto, and any method may be used as long as the low emissivity portion EM1 or the high emissivity portion EM2 is formed.

[ partial plating (2 thereof) ]

The partial plating treatment (1) is composed of 3 steps of (2-1) the 1 st plating step, (2-2) the 1 st masking step, and (2-3) the 2 nd plating step, described below.

(2-1) the 1 st plating step (the 1 st surface treatment step)

In the first plating step, a plating tank filled with a low emissivity plating liquid is prepared as a treatment tank filled with a low emissivity surface treatment liquid, and only the lower half of the rotating body 4 (specifically, the 1 st cylindrical body 4A) which is the portion of the entire outer surface of the rotating body 4 desired to be the low emissivity portion EM1 is immersed in the plating tank (treatment tank), whereby the low emissivity surface treatment is performed only on the lower half of the rotating body 4 (the portion of the entire outer surface of the rotating body 4 desired to be the low emissivity portion EM 1).

(2-2) Shielding step

In the masking step, the low emissivity coating layer formed by the low emissivity surface treatment in the 1 st plating step, that is, the lower half of the rotating body 4 is protected by a masking member or the like.

(2-3) the 2 nd plating step (the 2 nd surface treatment step)

In the 2 nd plating step, a plating tank filled with a high-emissivity plating liquid is prepared as a treatment tank filled with a high-emissivity surface treatment liquid, and the entire rotating body 4 shielded in the shielding step is immersed in the plating tank (treatment tank), thereby performing high-emissivity surface treatment on the entire outer surface of the rotating body 4. After that, the 2 nd masking member is removed.

Here, the plating treatment is used to form the low emissivity portion EM1 or the high emissivity portion EM2, but the present invention is not limited thereto, and any method may be used as long as the low emissivity portion EM1 or the high emissivity portion EM2 is formed. For example, in the case of performing a nickel oxide plating layer as a high emissivity surface treatment, the nickel alloy plating layer as a low emissivity portion may be left as it is unless the high emissivity treatment is performed by masking or the like of the portion as the low emissivity portion.

[ description of boundary Structure between Low emissivity portion and high emissivity portion ]

Fig. 6 is an explanatory diagram of a structure (boundary structure) in the vicinity of the boundary between the low emissivity region EM1 and the high emissivity region EM 2.

Referring to fig. 6, between the low emissivity section EM1 and the high emissivity section EM2 provided adjacent thereto, there is an intermediate section EM3 having an emissivity greater than that of the low emissivity section EM1 and smaller than that of the high emissivity section EM 2.

The high emissivity portion EM1 and the low emissivity portion EM2 as described above are set in a previously designed (set) range (hereinafter referred to as "design range"). However, in the above-described processing, for example, the lower surface side of the masking member MSK1 may be subjected to high emissivity surface processing. In this case, the intermediate portion EM3 as described above is formed. At this time, the intermediate portion EM3 is positioned within one of the design ranges a1 and a2 of the low-emissivity portion EM1 and the high-emissivity portion EM2 (the design range a1 of the low-emissivity portion EM1 in the example of fig. 5), so that the other design range (the design range a2 of the high-emissivity portion EM2 in the example of fig. 5) is configured by only the high-emissivity portion EM2 or the low-emissivity portion EM1 (the high-emissivity portion EM2 in the example of fig. 5) excluding the intermediate portion EM 3. Whether or not any of the design ranges a1 and a2 is configured by only one of the high emissivity section EM2 and the low emissivity section EM1 can be appropriately adjusted as necessary by shifting the position of the shielding member MSK 1.

Here, the intermediate portion EM3 refers to a portion where the emissivity distribution is generated, not with a uniform emissivity, due to the magnitude of the emissivity of the original low-emissivity portion EM1 and the high-emissivity portion EM2 and the high-emissivity surface treatment method.

[ other embodiments of the Low emissivity part and the high emissivity part ]

In the vacuum pump P of fig. 1 using the rotating body 4 of fig. 2, the outer surface Q2 of the 2 nd cylindrical body 4B and the outer surface Q3 of the rotor blade 6 are configured as the high emissivity portion EM2, whereby the amount of heat radiated in the direction from the 2 nd cylindrical body 4B to the exterior body 1 increases. Therefore, although not shown, the inner surface S2 of the 2 nd cylindrical body 4B may be configured as the high emissivity portion EM2 having a higher emissivity than the low emissivity portion EM1, so that the amount of heat radiated in the direction from the stator pole 3 to the 2 nd cylindrical body 4B may be increased to reduce overheating of the stator pole 3.

In the rotating body 4 of fig. 2, the end surface S4 of the 1 st cylindrical body 4A is also configured as the low emissivity portion EM1, but instead, the end surface S4 may be configured as a high emissivity portion EM2 having a higher emissivity than the low emissivity portion EM 1. With this configuration, the amount of heat radiated from the end surface S4 of the 1 st cylindrical body 4A in the direction of the pump mount B is increased, and the heat radiation performance of the entire rotating body 4 is improved.

In the rotating body 4 of fig. 2, the surfaces of all the rotor blades 6 are configured as the high emissivity sections EM2, but instead, as shown in fig. 7, the surface of the lowermost rotor blade 6E of the plurality of rotor blades 6 may be configured to include the low emissivity sections EM1 having a lower emissivity than the high emissivity sections EM 2.

With this configuration, the amount of heat radiated from the fixed member (specifically, the screw-groove pump stator 8) facing the lowermost rotor 6E toward the lowermost rotor 6E is reduced, and overheating of the rotor 6 is effectively reduced. Compared with the case where only the surface of the lowest-stage rotor blade 6E facing the screw groove pump stator 8 is configured as the low emissivity portion EM1, such a rotor blade overheating reduction effect can be more effectively obtained, and complicated shielding processing for shielding only the facing surface can be omitted.

Fig. 8 is an explanatory diagram of an example in which a member serving as a heat insulating member having a low emissivity portion is interposed between the lowermost rotor blade and the opposing fixed member.

Instead of configuring the surface of the lowermost rotor blade 6E as the low emissivity portion EM1 as described above, the rotor blade overheating reduction effect as described above can be obtained by a configuration in which a member (in the example of fig. 8, the lowermost stator blade 7E having a surface configured as the low emissivity portion EM 1) serving as a heat insulating member having a low emissivity portion is interposed between the lowermost rotor blade 6E and a stationary member (specifically, the screw-groove pump stator 8) facing the lowermost rotor blade 6E as shown in fig. 8.

Fig. 9 is an explanatory view of an example in which at least one of the upper and lower surfaces and the outer peripheral surface of the outer rim is configured as a low emissivity portion, and fig. 10 is an explanatory view of an example in which the abutting surfaces of the plurality of rim members are configured as low emissivity portions.

As described above, the vacuum pump P of fig. 1 has a structure in which the radially arranged rotor blades 6 and stator blades 7 are alternately arranged in a plurality of stages in the pump axial direction, that is, the stator blades 7 are provided between the rotor blades 6 in the pump axial direction among the plurality of rotor blades 6. As shown in fig. 9, the plurality of stationary blades 7 arranged in a radial pattern in each stage are configured such that the outer peripheral end portion 7A thereof is held by the outer rim 10 and the inner peripheral end portion 7B thereof is held by the inner rim 11. The plurality of stationary blades 7 are fixed (supported) to the inner circumferential surface of the pump casing C by sandwiching the outer circumferential portion of the outer rim 10 or the vicinity of the outer circumferential portion thereof with upper and lower spacers 9 (see fig. 1).

According to the above-described fixed structure of the stationary blade 7, since the heat of the stationary blade 7 is radiated to the exterior body 1 side by heat conduction through the outer rim 10 and the spacer 9, in order to improve the heat conductivity of the radiation path, it is preferable to configure at least one of the upper and lower surfaces and the outer peripheral surface of the outer rim 10 (in the example of fig. 9, the outer peripheral surface of the outer rim 10) as the low emissivity portion EM1 made of a nickel alloy plating layer or the like formed by electroless plating or nickel alloy plating treatment, as shown in fig. 9.

When it is desired to configure the contact portion of the outer peripheral surface of the outer rim 10 with the spacer 9 as the low emissivity portion EM1, for example, in a state where the stationary vanes 7 are butted and joined, a shielding member made of a rubber ring or the like may be attached to the outer peripheral surface of the outer rim 10, and high emissivity surface treatment may be performed in this state. In this case, the stationary blade 7 is a target of high emissivity surface treatment, while the portion of the outer peripheral surface of the outer rim 10 subjected to masking treatment that is in contact with the spacer 9 is a target of non-high emissivity surface treatment, i.e., is in an uncoated state, and therefore is configured as a low emissivity portion having a lower emissivity than the stationary blade 7.

Referring to fig. 9, the outer rim 10 is formed in an annular shape as a whole by butting and joining a plurality of rim members (in the example of fig. 9, two semicircular arc-shaped

rim members

10A and 10B (see fig. 10)), and the butting surfaces S5 of the plurality of

rim members

10A and 10B are preferably configured as a low emissivity portion EM1 made of a nickel alloy plating layer or the like formed by electroless plating or nickel alloy plating treatment, as shown in fig. 10.

With such a configuration, for example, when heat is accumulated in one of the rim members 10A in a concentrated manner, the concentrated heat is dispersed in the direction of the other rim member 10B, thereby effectively reducing overheating of the one rim member 10A.

As a method of configuring the abutting surfaces S5 of the

rim members

10A, 10B as the low emissivity portions EM1 as described above, for example, a method of performing a high emissivity surface treatment on the stationary blade 7 in a state where a plurality of

rim members

10A, 10B are abutted against and joined to each other may be considered.

According to this method, since the high emissivity surface treatment is not applied between the abutting surfaces S5 of the

rim members

10A and 10B, the abutting surfaces S5 have a lower emissivity than the high emissivity sections EM2 formed on the surface of the stationary blade 7 by the high emissivity surface treatment.

In the case where the low emissivity portion EM1 is formed of a nickel alloy plating layer and the high emissivity portion EM2 is formed of a nickel oxide, as shown in fig. 6, the low emissivity portion EM1 formed of a nickel alloy plating layer Me1 may be formed by applying a nickel alloy plating treatment to the surface to be plated, and then the high emissivity portion EM2 formed of a nickel oxide Me2 may be formed by oxidizing the surface of the nickel alloy plating layer Me1 with a chemical solution. In this case, the high emissivity portion EM2 made of the nickel oxide Me2 is formed on the low emissivity portion EM made of the nickel alloy plating layer Me 1.

As shown in fig. 11, the high emissivity section EM2 described above may be formed by forming a base layer Me0 made of nickel alloy plating on a surface to be plated, then forming a low emissivity section EM1 made of a nickel alloy plating layer Me1 on the base layer Me0, and then oxidizing the surface of the nickel alloy plating layer Me1 with a chemical solution (acid) to form a high emissivity section EM2 made of nickel oxide Me 2. In this case, the high emissivity portion EM2 composed of the nickel oxide Me2 is formed on the nickel alloy plating layer Me1, that is, provided on the uppermost layer of the multilayer structure (2-layer structure in the case of the present embodiment).

As an advantage in this case, a gap at the boundary between the low emission portion EM1 and the high emission portion EM2, which is likely to occur in the partial plating method (1 or 2), can be prevented, and a decrease in corrosion resistance to corrosive gas can be prevented. In addition, the number of pinholes generated in the low emissivity portion EM2 can be reduced.

[ description of the Shielding Member ]

Fig. 12 is an explanatory view of the surface roughness of the shielding member and the shielded surface, and fig. 13 is an explanatory view of a state in which the shielding member having elasticity is attached to the shielded surface.

Since the solution used for the high emissivity surface treatment in the above-described manufacturing methods 1 to 5 is acidic, a member having an acid resistance standard is preferable as the shielding member MSK1 used for the high emissivity surface treatment. As a material having acid resistance, there is a fluorine-containing rubber material.

Referring to fig. 12, the shielding member MSK1 and the shielded surface (in the example of the figure, the outer surface of the 1 st cylinder 4A) have respective inherent surface roughnesses SR1 and SR 2. Therefore, when the shielding member MSK1 is attached to the shielded surface, the gap G1 is inevitably generated between the shielding member MSK1 and the shielded surface due to the unevenness caused by the surface roughness, and there is a possibility that the high emissivity surface treatment is applied to the gap G1. Therefore, the shielding member MSK1 preferably has elasticity capable of deforming in a manner following the uneven shape caused by the surface roughness of the shielded surface.

Referring to fig. 13, the shielding member MSK1 having elasticity as described above is formed in a ring shape, and the inner diameter of the shielding member MSK1 is set to be smaller than the outer diameter of the 1 st cylindrical body 4A. When the shielding member MSK1 is attached to the outer surface of the 1 st cylindrical body 4A, the shielding member MSK1 that is elastically deformed and expanded at the time of attachment generates tension in the entire shielding member MSK1 by the restoring force that tries to return to the original state, and generates surface pressure due to the tension in the entire shielding member MSK1, so that the shielding member MSK1 deforms in conformity with the uneven shape due to the surface roughness of the shielded surface (the outer surface of the 1 st cylindrical body 4A), and the gap G1 as described above is small, and it is possible to reduce the cases where the low emissivity surface treatment or the high emissivity surface treatment is performed on the unnecessary portion.

In addition, the above-described embodiments may be used in combination.

The present invention is not limited to the embodiments described above, and many modifications can be made within the technical spirit of the present invention by a person having ordinary knowledge in the art.

[ description of reference numerals ]

1 outer package

1A air suction port

2 gas vent

3 stator pole

4 rotating body

41 rotating shaft

4A 1 st cylinder

4B No. 2 cylinder

4C connecting part

4D fastening joint

6 moving wing

6E lowest-level rotor blade

7 static wing

8 thread groove pump stator

8A thread groove

9 spacer

10 outer rim

10A, 10B rim parts

11 inner rim

Design Range of A1 Low emissivity part

Design Range of A2 high emissivity part

B pump base

BT fastening connecting bolt

C pump shell

G1 gap caused by surface roughness

EM1 low emissivity element

High emissivity EM2 part

EM3 intermediate section

H1 through hole (center through hole)

H2 through hole (peripheral through hole)

LID cover part

MSK1, MSK2 shield parts

MB magnetic bearing

MT driving motor

Me0 base layer

Me1 nickel alloy plating layer

Me2 Nickel oxide

P vacuum pump

PB plating tank

PC protective cover

R gas flow path

R1 suction side gas flow path

R2 exhaust side gas flow path

Outer surface of Q1 No. 1 cylinder

Outer surface of Q2 2 nd cylinder

Outer surface of Q3 rotor

R1 and R2 gas flow paths

Inner surface of S rotary body

S1 inner surface of 1 st cylinder

S2 inner surface of 2 nd cylinder

S3 fastening the inner surface of the joint

End surface of S4 1 st cylinder

S5 abutting surface of outer rim.

Claims

1. A vacuum pump for sucking and discharging gas by rotation of a rotating body, the vacuum pump being characterized in that,

the rotating body includes: a1 st cylindrical body constituting a screw groove pump mechanism portion, a2 nd cylindrical body constituting a turbo molecular pump mechanism portion in which a plurality of vanes are arranged in multiple stages on an outer peripheral surface, and a through hole for fastening and connecting to a rotary shaft,

a cylindrical inner surface formed by an inner surface of the 1 st cylindrical body and an inner surface of the 2 nd cylindrical body, and an outer surface of the 1 st cylindrical body are formed as a low emissivity portion having an emissivity smaller than a surface of the rotor blade,

the through-hole has a contact surface which comes into contact with a lid member which closes the through-hole, the contact surface coming into contact with the lid member to close the entry of the high-emissivity surface treatment liquid into the through-hole, and the outer surface of the 2 nd cylindrical body and the surface of the rotor blade are subjected to high-emissivity surface treatment to provide a high-emissivity portion, so that the contact surface and the cylindrical inner surface constitute a low-emissivity portion having an emissivity smaller than that of the surface of the rotor blade.

2. Vacuum pump according to claim 1,

an intermediate portion having an emissivity greater than that of the low emissivity portion and less than that of the high emissivity portion is provided between the low emissivity portion and the high emissivity portion.

3. Vacuum pump according to claim 1,

in one of the respective design ranges of the high emissivity portion and the low emissivity portion, an intermediate portion having an emissivity greater than that of the low emissivity portion and less than that of the high emissivity portion is present, and the other design range is constituted by only the high emissivity portion or the low emissivity portion excluding the intermediate portion.

4. Vacuum pump according to claim 1,

the surface of the lowermost rotor blade among the rotor blades is configured as the low emissivity portion.

5. Vacuum pump according to claim 1,

in the rotor at the lowest stage among the rotors, the low emissivity portion is formed on a surface of the rotor facing a fixing member of the screw pump mechanism portion.

6. Vacuum pump according to claim 1,

a shielding member is disposed between the lowermost rotor among the rotors and a fixing member of the screw pump mechanism, and the low emissivity portion is formed in the shielding member.

7. Vacuum pump according to claim 1,

a stationary vane is provided between the rotor vanes in the axial direction of the pump among the rotor vanes,

the stationary blade includes an outer rim supported at an outer peripheral portion of the outer rim and/or in the vicinity of the outer peripheral portion,

at least one of the upper and lower surfaces and the outer peripheral surface of the outer rim is configured as the low emissivity portion.

8. Vacuum pump according to claim 1,

a stationary vane is provided between the rotor vanes in the axial direction of the pump,

the outer rim is formed in an annular shape as a whole by abutting and joining a plurality of rim members,

the abutting surface of the rim member is configured as the low emissivity portion.

9. Vacuum pump according to claim 1,

the low emissivity unit is formed of a multilayer structure in which a1 st low emissivity unit and a2 nd low emissivity unit are stacked.

10. A method of manufacturing a stationary blade of a vacuum pump, which is the vacuum pump according to any one of claims 1 to 9,

the outer rim of the stationary blade provided between the moving blades is formed into an annular shape as a whole by butting and joining a plurality of rim members,

the high emissivity surface treatment is applied to the stationary blade in a state where the rim members are butted and joined, so that the butting surface of the rim members is in a state where the high emissivity portion formed on the surface of the stationary blade by the high emissivity surface treatment has a lower emissivity.

11. A method for manufacturing a rotating body of a vacuum pump, the rotating body of the vacuum pump being provided with: the method for manufacturing a rotating body of a vacuum pump includes a1 st cylindrical body constituting a screw groove pump mechanism portion, a2 nd cylindrical body constituting a turbo molecular pump mechanism portion in which a plurality of vanes are arranged in multiple stages on an outer peripheral surface, and a through hole for fastening and connecting to a rotating shaft, the method for manufacturing a rotating body of a vacuum pump including:

a protection step of sealing the through-hole having a contact surface with the lid member with a lid member so as to seal the penetration of the high-emissivity surface treatment liquid into the through-hole, in order to protect a cylindrical inner surface formed by an inner surface of the 1 st cylindrical body and an inner surface of the 2 nd cylindrical body from the high-emissivity surface treatment; and

and a surface treatment step of performing the high emissivity surface treatment on the outer surface of the 2 nd cylindrical body and the rotor blade after the protection step.

12. A rotary body, characterized by being used in the vacuum pump according to any one of claims 1 to 9.

13. A stator vane, characterized by being used in a vacuum pump according to any one of claims 1 to 9.