JPS6375386A - Hybrid vacuum pump - Google Patents

Hybrid vacuum pump

Info

Publication number
JPS6375386A
JPS6375386A JP21819686A JP21819686A JPS6375386A JP S6375386 A JPS6375386 A JP S6375386A JP 21819686 A JP21819686 A JP 21819686A JP 21819686 A JP21819686 A JP 21819686A JP S6375386 A JPS6375386 A JP S6375386A
Authority
JP
Japan
Prior art keywords
vacuum pump
rotating body
thread groove
bearing
rotor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP21819686A
Other languages
Japanese (ja)
Inventor
Nobuyoshi Nakaishi
中石　信義
Harushige Osawa
大沢　晴繁
Satoshi Hata
聰 秦
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Heavy Industries Ltd
Original Assignee
Mitsubishi Heavy Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Heavy Industries Ltd filed Critical Mitsubishi Heavy Industries Ltd
Priority to JP21819686A priority Critical patent/JPS6375386A/en
Publication of JPS6375386A publication Critical patent/JPS6375386A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE:To improve an exhaust characteristic, by installing a turbo-molecular pump having multistage rotor-stator blades and a thread groove vacuum pump having a thread groove both in a casing separately. CONSTITUTION:A turbo-molecular pump part having multistage rotor blades 1a and a rotor 1b is installed in each of casings 8 and 9. A thread groove vacuum pump part having a hollow stationary body 14 with a thread groove in the inner circumferential surface and a rotor 2 is installed in a casing 15. Therefore, a rotor for the thread groove vacuum pump to become overhung to a bearing support point is no longer required, so that a compression ratio can be made larger and, what is more, an exhaust characteristic is improvable.

Description

【発明の詳細な説明】 （産業上の利用分野） 本発明はハイブリッド真空ポンプに関するものである。[Detailed description of the invention] (Industrial application field) The present invention relates to a hybrid vacuum pump.

（従来の技術） 高真空領域で高い排気性能を有するターボ分子ポンプと
低真空領域で高い排気性能を有するねじ溝真空ポンプと
を具えた複合型真空ポンプの従来例を第３図により説明
すると、　（Ｏｌａ）がターボ分子ポンプの多段の動翼
、　（Ｏｌｂ）が同各動翼（Ｏｌａ）をもつターボ分子
ポンプの回転体、　（Ｏｌｅ）がねし溝真空ポンプの回
転体、　（Ｏｌｄ）がねし溝真空ポンプの回転軸（回転
体）　、　（０２ａ）がターボ分子ポンプのケーシング
、　（０２ｂ）がねじ溝真空ポンプのゲージング、　（
０２ｃ）が内周面にねじ溝をもつねし溝真空ポンプの中
空静止体である。なお上記各動翼（Ｏｌａ）と上記回転
体（Ｏｌｂ）〜（ＯＭ）とは金属製で、上記回転体（Ｏ
ｌｂ）　（Ｏｌｄ）が一体に作られ、上記ケーシング（
０２ａ）　（０２ｂ）が一体に作られている。また（０
３）が上部ラジアル軸受（油潤滑式玉軸受）、（０４）
が下部ラジアル軸受（油潤滑式玉軸受）、（０５）がス
ラスト軸受（油潤滑式玉軸受）で、同上下のラジアル軸
受（０３）　（０４）と同スラスト軸受（０５）とによ
り上記駆動Ｎ（Ｏｌａ）及び回転体（Ｏｌｈ）　〜（Ｏ
ｌｄ）が上記ケーシング（０２ａ）　（０２ｂ）内に回
転可能に支持されている。また（０６）が駆動モータ、
　（０７）がターボ分子ポンプの多段の静翼で、各動翼
（Ｏｌａ）及び回転体（０ｌｂ）〜（Ｏｌｄ）を駆動モ
ータ（０６）により高速回転させ・矢印（ＡＩ）−矢印
（Ａ　ｚ）方向に排気して、　（ＡＩ）側に高真空を発
生させる。このとき、　　（Ａｘ）側では大気圧近傍の
圧力で排気している。(Prior Art) A conventional example of a composite vacuum pump equipped with a turbo molecular pump that has high evacuation performance in a high vacuum region and a thread groove vacuum pump that has high evacuation performance in a low vacuum region will be explained with reference to FIG. (Ola) is the multi-stage moving blade of a turbo-molecular pump, (Olb) is the rotating body of the turbo-molecular pump with each moving blade (Ola), (Ole) is the rotating body of the grooved vacuum pump, (Old) is The rotating shaft (rotating body) of the thread groove vacuum pump, (02a) is the casing of the turbo molecular pump, (02b) is the gauging of the thread groove vacuum pump, (
02c) is a hollow stationary body of a twin groove vacuum pump with a threaded groove on the inner peripheral surface. Note that each of the rotor blades (Ola) and the rotating bodies (Olb) to (OM) are made of metal, and the rotating body (Ola) is made of metal.
lb) (Old) is made in one piece, and the above casing (
02a) (02b) are made in one piece. Also (0
3) is the upper radial bearing (oil lubricated ball bearing), (04)
is the lower radial bearing (oil-lubricated ball bearing), and (05) is the thrust bearing (oil-lubricated ball bearing). (Ola) and rotating body (Olh) ~(O
ld) are rotatably supported within the casings (02a) (02b). In addition, (06) is the drive motor,
(07) is the multi-stage stator vane of the turbo molecular pump, and each rotor blade (Ola) and rotating bodies (0lb) to (Old) are rotated at high speed by the drive motor (06) - Arrow (AI) - Arrow (A z ) direction to generate high vacuum on the (AI) side. At this time, the air is exhausted on the (Ax) side at a pressure close to atmospheric pressure.

（発明が解決しようとする問題点） 前記第３図に示す従来の複合型真空ポンプでは。(Problem that the invention attempts to solve) In the conventional composite vacuum pump shown in FIG.

ねじ溝真空ポンプの回転体（Ｏｌｅ）が軸受支持点に対
してオーバハングになり１回転体（Ｏｌｂ）〜（０１ｄ
）の振幅が増大して１回転側が静止側に接触する慣れが
あり１回転側と静止側との間のクリアランス、ねじ溝真
空ポンプについて云えば９回転体（Ｏｌｅ）と中空静止
体（０２ｃ）との間のクリアランスδを大きくとる必要
がある。即ち、ねじ溝真空ポンプの軸方向長さをｌとす
ると、排気特性、特に圧縮比は１／δ２に比例するので
、圧縮比を大きくして、大気圧近傍で排気するためには
、ねじ溝真空ポンプの軸方向長さｐを著しく長くしなけ
ればならないが、ねじ溝真空ポンプの軸方向長さｌを長
くすると９回転体（Ｏｌｅ）が一層オーバハング構造に
なり２回転体（Ｏｌｂ）〜（Ｏｌｄ）の回転安定性が低
下して２回転体（Ｏｌｒ、）が中空静止体（０２ｃ）に
接触する惧れがあるので１回転体（Ｏｌｅ）と中空静止
体（０２ｃ）　との間のクリアランスδを大きくとる必
要がある。しかしクリアランスδを大きくとると、圧縮
比が小さくなって、排気特性が低下するという問題があ
った。The rotating body (Ole) of the thread groove vacuum pump overhangs the bearing support point, and the rotating body (Olb) ~ (01d)
) increases and the one-rotation side is accustomed to contacting the stationary side, and the clearance between the one-rotation side and the stationary side.For thread groove vacuum pumps, there is a 9-rotating body (Ole) and a hollow stationary body (02c). It is necessary to provide a large clearance δ between the In other words, if the axial length of a thread groove vacuum pump is l, the exhaust characteristics, especially the compression ratio, are proportional to 1/δ2. Therefore, in order to increase the compression ratio and exhaust near atmospheric pressure, the thread groove should be The axial length p of the vacuum pump must be significantly increased, but if the axial length l of the threaded groove vacuum pump is increased, the 9-rotator (Ole) will have an even more overhang structure, and the 2-rotator (Olb) ~ ( There is a risk that the rotational stability of the rotating body (Olr, ) may deteriorate and the two rotating bodies (Olr, ) come into contact with the hollow stationary body (02c), so the clearance between the single rotating body (Ole) and the hollow stationary body (02c) is It is necessary to take a large value δ. However, if the clearance δ is made large, there is a problem in that the compression ratio becomes small and the exhaust characteristics deteriorate.

（問題点を解決するための手段） 本発明は前記の問題点に対処するもので、多段の動翼を
もつ回転体と同回転体を回転可能に支持する軸受と同回
転体を駆動する駆動モータとを具えたターボ分子ポンプ
、及び内周面にねじ溝をもつ中空静止体と同中空静止体
内に挿入した回転体と同回転体を回転可能に支持する軸
受と同回転体を駆動する駆動モータとを具えたねじ溝真
空ポンプを有し、同ターボ分子ポンプと同ねじ溝真空ポ
ンプとをケーシング内に別々に設けたことを特徴とする
ハイブリッド真空ポンプに係わり、その目的とする処は
、排気特性を向上できるハイブリッド真空ポンプを供す
る点にある。(Means for Solving the Problems) The present invention addresses the above-mentioned problems, and includes a rotating body having multi-stage moving blades, a bearing that rotatably supports the rotating body, and a drive that drives the rotating body. a turbo-molecular pump comprising a motor, a hollow stationary body having a thread groove on its inner peripheral surface, a rotating body inserted into the hollow stationary body, a bearing rotatably supporting the rotating body, and a drive for driving the rotating body. The present invention relates to a hybrid vacuum pump having a thread groove vacuum pump equipped with a motor, and characterized in that the turbo molecular pump and the thread groove vacuum pump are separately provided in a casing, and its purpose is to: The object of the present invention is to provide a hybrid vacuum pump that can improve exhaust characteristics.

（作用） 本発明のハイブリッド真空ポンプは前記のように多段の
動翼をもつ回転体と同回転体を回転可能に支持する軸受
と同回転体を駆動する駆動モータとを具えたターボ分子
ポンプと、内周面にねじ溝をもつ中空静止体と同中空静
止体内に挿入した回転体と同回転体を回転可能に支持す
る軸受と同回転体を駆動する駆動モータとを具えたねじ
溝真空ポンプとをケーシング内に別々に設けており、軸
受支持点に対してオーバハングになるねじ溝真空ポンプ
の回転体（第３図の（ｌｃ）参照）が不要で。(Function) As described above, the hybrid vacuum pump of the present invention is a turbo-molecular pump comprising a rotary body having multistage rotor blades, a bearing that rotatably supports the rotary body, and a drive motor that drives the rotary body. , a thread groove vacuum pump comprising a hollow stationary body having a thread groove on its inner peripheral surface, a rotating body inserted into the hollow stationary body, a bearing that rotatably supports the rotating body, and a drive motor that drives the rotating body. and are provided separately in the casing, eliminating the need for the rotating body of the thread groove vacuum pump (see (lc) in Figure 3) that overhangs the bearing support point.

低真空用ねし溝真空ポンプの軸方向長さを長くしても２
回転安定性が低下せず１回転体と中空静止体との間に僅
かなりリアランスを形成すればよく。Even if the axial length of the low vacuum threaded groove vacuum pump is increased, the
It is only necessary to form a slight clearance between the rotating body and the hollow stationary body without reducing the rotational stability.

ｉ／δ２に比例する圧縮比が大きくなって、排気特性が
向上する。The compression ratio, which is proportional to i/δ2, increases, and the exhaust characteristics improve.

（実施例） 次に本発明のハイブリッド真空ポンプを第１図に示す一
実施例により説明する。まず高真空用ターボ分子ポンプ
側について説明すると、　（ｌａ）が多段の動翼、　（
ｌｂ）が同各動翼（１ａ）をもつ回転体、（３）が上部
ラジアル軸受（油潤滑式玉軸受）、（４）が下部ラジア
ル軸受（油潤滑式玉軸受）、（５）がスラスト軸受（油
潤滑式玉軸受）、（６）が駆動モータ、（７）がターボ
分子ポンプの多段の静Ｈ，（８）　（９）がケーシング
で、上記上下のラジアル軸受（３）　（４）と上記スラ
スト軸受（５）とにより上記各動翼（１ａ）及び回転体
（ｌｂ）が上記ケーシング（８）　（９）内に回転可能
に支持されている。次に低真空用ねし溝真空ポンプにつ
いて説明すると、（２）が回転体、　（１０）が上部ラ
ジアル軸受（油潤滑式玉軸受）、（１１）が下部ラジア
ル軸受（油潤滑式玉軸受）、（１２）がスラスト軸受（
油潤滑式玉軸受）、　（１３）が駆動モータ８（１４）
が内周面にねじ溝をもつ中空静止体、　（１５）がケー
シングで、上記上下のラジアル軸受（１０）　（１１）
と上記スラスト軸受（１２）とにより上記回転体（２）
が上記ケーシング（１５）内に回転可能に支持されてい
る。(Example) Next, a hybrid vacuum pump of the present invention will be explained using an example shown in FIG. First, to explain the high vacuum turbomolecular pump side, (la) is a multi-stage rotor blade, (
lb) is a rotating body with the same rotor blades (1a), (3) is an upper radial bearing (oil-lubricated ball bearing), (4) is a lower radial bearing (oil-lubricated ball bearing), and (5) is a thrust Bearings (oil-lubricated ball bearings), (6) is the drive motor, (7) is the multi-stage static H of the turbo molecular pump, (8) (9) is the casing, and the upper and lower radial bearings (3) (4) The rotor blades (1a) and the rotating body (lb) are rotatably supported within the casings (8) and (9) by the thrust bearing (5) and the thrust bearing (5). Next, to explain the threaded groove vacuum pump for low vacuum, (2) is the rotating body, (10) is the upper radial bearing (oil-lubricated ball bearing), and (11) is the lower radial bearing (oil-lubricated ball bearing). , (12) is the thrust bearing (
oil-lubricated ball bearing), (13) is the drive motor 8 (14)
is a hollow stationary body with a thread groove on its inner peripheral surface, (15) is a casing, and the above-mentioned upper and lower radial bearings (10) (11)
and the thrust bearing (12), the rotating body (2)
is rotatably supported within the casing (15).

次に前記第１図に示すハイブリッド真空ポンプの作用を
具体的に説明する。高真空用ターボ分子ポンプの勅ｍ（
ｌａ）及び回転体（１ｂ）を駆動モータ（６）により高
速回転させ、低真空用ねじ溝真空ポンプの回転体（２）
を駆動モータ（１３）により高速回転させ、矢印（八〇
−（Ａ２）−＜Δａ）＝（ＡＪ方向に排気して、（ＡＩ
）側に高真空を発生させる。このとき。Next, the operation of the hybrid vacuum pump shown in FIG. 1 will be explained in detail. Regulation of turbomolecular pumps for high vacuum (
The rotating body (2) of the thread groove vacuum pump for low vacuum is rotated at high speed by the drive motor (6).
is rotated at high speed by the drive motor (13), exhausted in the direction of arrow (80-(A2)-<Δa)=(AJ, and (AI
) side to generate a high vacuum. At this time.

（Ａ４）側では大気圧近傍の圧力で排気している。On the (A4) side, exhaust is performed at a pressure near atmospheric pressure.

第２図は、低真空用ねし溝真空ポンプの中空静止体（１
４ａ）　（１４ｂ）を上下２段に配設し、駆動モータに
コンパクトなヒステリシスモータ（１３）　ヲ（１１し
た他の実施例で、高真空用ターボ分子ポンプの動翼（１
ａ）及び回転体（１ｂ）を駆動モータ（６）により高速
回転させ、低真空用ねじ溝真空ポンプの回転体（２）を
ヒステリシスモータ（１３）により高速回転させ、矢印
（八、）−（八２）＝（八３）　−（Ａ４）方向に排気
して。Figure 2 shows a hollow stationary body (1
4a) (14b) are arranged in two stages, upper and lower, and a compact hysteresis motor (13) is used as the drive motor.
a) and the rotating body (1b) are rotated at high speed by the drive motor (6), and the rotating body (2) of the low vacuum screw groove vacuum pump is rotated at high speed by the hysteresis motor (13). 82) = (83) - Exhaust in the (A4) direction.

（八、）側に高真空を発生させるようになっている。A high vacuum is generated on the (8) side.

なお前記各実施例ではねし溝真空ポンプが１軸の構成に
なっているが、２軸以上の構成にしてもよい。In each of the embodiments described above, the groove vacuum pump has a single-shaft configuration, but it may have a configuration with two or more shafts.

（発明の効果） 本発明のハイブリッド真空ポンプは前記のように多段の
動翼をもつ回転体と同回転体を回転可能に支持する軸受
と同回転体を駆動するモータとを具えたターボ分子ポン
プと、内周面にねじ溝をもつ中空静止体と同中空静止体
内に挿入した回転体と同回転体を回転可能に支持する軸
受と同回転体を駆動するモータとを具えたねじ溝真空ポ
ンプとをケーシング内に別々に設けており、軸受支持点
に対してオーバハングになるねし溝真空ポンプの回転体
（第３図の（１ｃ）参照）が不要で、低真空用ねじ溝真
空ポンプの軸方向長さを長くしても８回転安定性が低下
せず２４回転体と中空静止体との間に僅かなりリアラン
スを形成すればよく、圧縮比を大きくできて、排気特性
を向上できる効果がある。(Effects of the Invention) As described above, the hybrid vacuum pump of the present invention is a turbo-molecular pump that includes a rotating body having multi-stage moving blades, a bearing that rotatably supports the rotating body, and a motor that drives the rotating body. a threaded groove vacuum pump comprising: a hollow stationary body having a threaded groove on its inner peripheral surface; a rotating body inserted into the hollow stationary body; a bearing that rotatably supports the rotating body; and a motor that drives the rotating body. and are provided separately in the casing, eliminating the need for the rotating body of the threaded groove vacuum pump (see (1c) in Figure 3) that overhangs the bearing support point, and making it easier to use the threaded groove vacuum pump for low vacuum applications. Even if the length in the axial direction is increased, the 8-rotation stability does not deteriorate, and it is only necessary to create a slight clearance between the 24-rotation body and the hollow stationary body, which allows the compression ratio to be increased and the exhaust characteristics to be improved. There is.

以上本発明を実施例により説明したが、勿論本発明はこ
のような実施例だけに局限されるものでなく１本発明の
精神を逸脱しない範囲で種々の設計の改変を施しうるち
のである。Although the present invention has been described above with reference to embodiments, it goes without saying that the present invention is not limited to these embodiments, and can be modified in various ways without departing from the spirit of the present invention.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は本発明に係わるハイブリッド真空ポンプの一実
施例を示す縦断側面図、第２図は他の実施例を示す縦断
側面図、第３図は従来の複合型真空ポンプを示す縦断側
面図である。 （１ａ）・・・ターボ分子ポンプの多段の動翼、　（ｌ
ｂ）・・・回転体、　（３）　（４）（５）・・・軸受
、（６）・・・駆動モータ、（２）・・・ねじ溝真空ポ
ンプの回転体、　（１０）（１１）・・・軸受、　（１
３）・・・駆動モータ、　（１／Ｉ）・・・中空静止体
。 復代理人弁理士岡本重文外２名 第３図 Ｑ５FIG. 1 is a longitudinal side view showing one embodiment of a hybrid vacuum pump according to the present invention, FIG. 2 is a longitudinal side view showing another embodiment, and FIG. 3 is a longitudinal side view showing a conventional compound vacuum pump. It is. (1a)...Multi-stage rotor blades of a turbomolecular pump, (l
b)... Rotating body, (3) (4) (5)... Bearing, (6)... Drive motor, (2)... Rotating body of thread groove vacuum pump, (10) (11 )...Bearing, (1
3)...Drive motor, (1/I)...Hollow stationary body. Sub-agent Patent Attorney Shigemon Okamoto (2 persons) Figure 3 Q5

Claims (1)

【特許請求の範囲】[Claims] 多段の動翼をもつ回転体と同回転体を回転可能に支持す
る軸受と同回転体を駆動する駆動モータとを具えたター
ボ分子ポンプ、及び内周面にねじ溝をもつ中空静止体と
同中空静止体内に挿入した回転体と同回転体を回転可能
に支持する軸受と同回転体を駆動する駆動モータとを具
えたねじ溝真空ポンプを有し、同ターボ分子ポンプと同
ねじ溝真空ポンプとをケーシング内に別々に設けたこと
を特徴とするハイブリッド真空ポンプ。A turbo-molecular pump comprising a rotating body with multi-stage moving blades, a bearing that rotatably supports the rotating body, and a drive motor that drives the rotating body, and a hollow stationary body with threaded grooves on its inner circumferential surface. It has a thread groove vacuum pump that includes a rotating body inserted into a hollow stationary body, a bearing that rotatably supports the rotating body, and a drive motor that drives the rotating body, and the same thread groove vacuum pump as the turbo molecular pump. A hybrid vacuum pump characterized by having and separately provided in a casing.
JP21819686A 1986-09-18 1986-09-18 Hybrid vacuum pump Pending JPS6375386A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP21819686A JPS6375386A (en) 1986-09-18 1986-09-18 Hybrid vacuum pump

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP21819686A JPS6375386A (en) 1986-09-18 1986-09-18 Hybrid vacuum pump

Publications (1)

Publication Number Publication Date
JPS6375386A true JPS6375386A (en) 1988-04-05

Family

ID=16716120

Family Applications (1)

Application Number Title Priority Date Filing Date
JP21819686A Pending JPS6375386A (en) 1986-09-18 1986-09-18 Hybrid vacuum pump

Country Status (1)

Country Link
JP (1) JPS6375386A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5118251A (en) * 1989-12-28 1992-06-02 Alcatel Cit Compound turbomolecular vacuum pump having two rotary shafts and delivering to atmospheric pressure
US5445502A (en) * 1992-01-23 1995-08-29 Matsushita Electric Industrial Co., Ltd. Vacuum pump having parallel kinetic pump inlet section
JP2007507659A (en) * 2003-09-30 2007-03-29 ザ ビーオーシー グループ ピーエルシー Vacuum pump
US7866940B2 (en) 2003-09-30 2011-01-11 Edwards Limited Vacuum pump
JP2020534478A (en) * 2017-09-20 2020-11-26 エドワーズ リミテッド A set of vacuum pumps including drag pumps and drag pumps

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5118251A (en) * 1989-12-28 1992-06-02 Alcatel Cit Compound turbomolecular vacuum pump having two rotary shafts and delivering to atmospheric pressure
US5445502A (en) * 1992-01-23 1995-08-29 Matsushita Electric Industrial Co., Ltd. Vacuum pump having parallel kinetic pump inlet section
JP2007507659A (en) * 2003-09-30 2007-03-29 ザ ビーオーシー グループ ピーエルシー Vacuum pump
US7866940B2 (en) 2003-09-30 2011-01-11 Edwards Limited Vacuum pump
JP4806636B2 (en) * 2003-09-30 2011-11-02 エドワーズ リミテッド Vacuum pump
JP2020534478A (en) * 2017-09-20 2020-11-26 エドワーズ リミテッド A set of vacuum pumps including drag pumps and drag pumps

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