200819629 九、發明說明: 【發明所屬之技術領域】 本發明係關於一種真空泵,其具有一電動驅動馬達, 該馬達包括有一馬達轉子和一馬達定子。 【先前技術】 ' 關於具有轉子驅動之電動驅動馬達的真空泵,已知有 不同之結構用以相對該驅動馬達將泵之真空傳送部分密 封。一個解決方式在於將驅動馬達完全地配置於真空的外 側且致使馬達軸經過泵外殼的開口。在外殼通道處之軸密 封必須具有一真空密閉構造,例如其可藉由油封軸密封件 而實現。然而,此種密封件絕對不適用於無油之操作中。 另一種結構上的解決方式在於將藉由一分隔件隔離之 馬達轉子設置於真空中,同時馬達定子則於真空外側或大 氣中配置在分隔件外側。然而,分隔件需承擔不可避免的 電氣技術缺點,即更差的效率和惡化的功率因數,及因之 而產生的相對較大的驅動馬達和較高的熱量損失。 【發明內容】 因此,本發明之一目的在於提供具有電動驅動馬達之 真空泵,該電動驅動馬達具有高效率且無須任何的軸密封 件。 依據本發明,該目的可藉由具有申請專利範圍第1項 之特徵的真空泵而解決。 依據本發明之真空泵中,馬達定子係在真空中配置於 真空密閉的馬達外殼內。此外,馬達定子被鑄造於由一合 200819629 適的鑄造複合物所製成之鑄造複合體中。依據本發明,相 較於一分隔件之馬達,不僅馬達轉子而且馬達定子亦配置 於真空空間內,換言之,不需從真空泵的真空傳送部分密 封地分離。如果需要的話,轉子外殻僅具有一開口,經由 此開口用以驅動馬達之控制和朝供電線路外導引至馬達外 殻外側。由控制和供電線路.所呈現之固定部分的真空密閉 密封,則較一可移動部分相對一固定部分之密封,例如軸 密封,來的簡單。由於馬達轉子和馬達定子皆配置於真空 中,可省去軸密封並可完成真空泵之真空空間不會洩漏且 可靠之永久密封。 藉由將一分隔件省去,介於馬達轉子和馬達定子間之 間隙則可減小至一結構上所需的最小値。藉此,分別相當 顯著地改善驅動馬達的效率和功率因數。藉此,依次地, 可使用更小的電動驅動馬達以產生相同的軸輸出。由於較 小的電磁損失,則所產生之熱量也相當顯著地改善減小, 藉此可在結構上進一歩簡化。 馬達定子係禱造於鐘造複合物中,一^或多個馬逢定子 線圈係纟尋造於任何例子中的鑄造複贫體中。由於不這樣作 則會在真空中介於一或多個定子線圈繞組之間發生閃絡 (flashover)電壓,故此爲必要的。鑄造複合物相較於非鑄 造複合物真空裝置係爲良好的電絕緣體。此外,鑄造複合 物因爲其熱傳導性而確保熱量可被帶走。馬達定子的成束 疊片也可完全地或部分地鑄造入鑄造複合體內,但非爲必 要的。 200819629 鑄造複合物之另一重要的特性係具有一低的氣體透出 性和良好的耐腐飩性。 馬達定子包含一或多個線圈及一束疊片,此一或多個 線圈及該束疊片係鑄造於鑄造複合體中。 依據一較佳實施例,鑄造複合材料係爲環氧樹脂。環 氧樹脂係爲良好的電絕緣體,具有高的熱傳導性且適用於 在一相當低溫下以相對簡單的方式被鑄造。 依據一較佳實施例,鑄造複合物包含具有熱傳導性比 該鑄造複合物材料更佳之塡充料。藉此,增加鑄造複合物 之熱傳導性,使得更多的熱量可被帶走。 較佳地,設置有通過馬達外殼開口之線路通道,且鑄 造複合物具有軸向地突入開口的突出部,換言之,沿著驅 動馬達和泵轉子之軸線。突出部係與鑄造複合體的鑄造複 合物整體地形成。用以供電給驅動馬達的線路和其他線 路,如果需要的話,係盡可能中間地軸向配置於突出部中。 通道之真空密閉密封係藉由合適的密封手段,例如藉由一 橡膠彈性〇型環而形成於鑄造複合物突出部和開口邊緣之 間。然而,實際的真空密閉密封也會受到分隔開口蓋的影 響,該分隔開口蓋係依序藉由橡膠彈性〇型環相對馬達外 殼開口的邊緣而密封且包括用於通道之合適的接觸銷。 較佳地,驅動馬達係爲一無刷直流或非同步馬達。由 於其係爲無刷式的,這種馬達係特別適合作爲真空泵的驅 動馬達。 依據一較佳實施例,真空栗係爲一羅茨(Roots)真空 200819629 泵。由於其結構,驅動馬達或驅動馬達的零件通常配置於 羅茨(R ο 〇 t s )真空泵的真空側,使得此導致驅動馬達之真空 密閉密封的需求,特別是使用於羅茨(Roots)真空泵。 【實施方式】 以下,將參考圖式而詳細說明本發明的一實施例。 在第1圖中,羅茨(Roots)真空泵10係以縱向區域的方 式說明,且除了別的以外,包括有一電動驅動馬達1 2、第 一泵轉子1 4和構成爲滾動軸承之兩軸承1 6、1 8。兩滾動 軸承之其中一個軸承1 8係軸向地配置於泵轉子1 4和驅動 馬達1 2之間。與第一泵轉子配合之第二泵轉子未繪出。 實質上,真空泵10的外殻19係由傳動外殼20、泵外 殼 22和馬達外殼24所組成。由馬達定子28和安裝於軸 3 2上之馬達轉子3 0所形成的驅動馬達1 2係配置在真空密 封之金屬馬達外殻24中。 驅動馬達1 2係爲無刷直流馬達,但也可構造成無刷非 同步馬達。在任何例子中,驅動馬達1 2具有一無刷構造。 整個真空泵外殼1 9具有一真空密閉式構造。特別地該 馬達外殻24具有一真空密閉式構造。因此,在馬達外殼 24內約產生與在泵轉子14之鄰近端部相同的氣體壓力。 除了別的以外,這對於用以避免從馬達外殼24朝向泵轉子 1 4氣流係爲必須的,該氣流可能非所欲的從馬達外殼24 傳送潤滑油至泵區域。 在馬達側軸承1 8和泵轉子1 4之間設置有密封配置 3 4,該密封配置3 4實質上係爲潤滑油密封件且避免潤滑油 4 200819629 從馬達外殻24進入泵外殼22。 在一束疊片40上,馬達定子28包括一些線圈42。由 該束暨片40和線圈42所形成之馬達定子28係完全地禱造 於ί署造複合物44的繪造複合體43中。因此,鑄造複合體 4 3形成一封閉環。鑄造複合物4 4係由環氧樹脂所組成, 且包含具有熱傳導性比鑄造複合物材料更佳之塡充料。諸 如砂等的電磁中性材料係特別地適合作爲塡充料。 在第2圖中’通過軸向馬達外殻開口 48之線路通道 ^ 46以放大比例來作說明。鑄造複合物突出部6〇軸向地突 入開口 48並超過開口長度的一部份。開口 48和突出部60 係軸向地配置,換言之,平行於驅動馬達的軸線。實際的 真空密閉密封係被藉由Ο形環6 4相對外殼2 4而密封之蓋 ό 2所影響。將電線5 0向外接通之一或多個接觸銷5 〇,係鑄 造於蓋62中。電線50作用以供應電力至馬達定子28、至 磁性軸承,而如果需要的話,亦可傳送感應器資料。 【圖式簡單說明】 w 第1圖顯示羅茨(Roots)真空泵之縱向區域;及 第2圖係放大第1圖之真空泵的線路通道。 【主要元件符號說明】 10 真空泵 12 電動驅動馬達 14 泵轉子 16 軸承 18 軸承 200819629 19 外殻 20 傳動外殼 22 泵外殼 24 馬達外殼 28 馬達定子 30 馬達轉子 32 軸 34 密封配置 40 疊片 42 線圈 43 鑄造複合體 44 鑄造複合物 46 線路通道 48 開口 50 電線 50? 接觸銷 60 突出部 62 蓋 64 〇形環200819629 IX. Description of the Invention: TECHNICAL FIELD The present invention relates to a vacuum pump having an electric drive motor including a motor rotor and a motor stator. [Prior Art] 'With regard to a vacuum pump having a rotor-driven electric drive motor, a different structure is known for sealing the vacuum transfer portion of the pump with respect to the drive motor. One solution consists in completely arranging the drive motor on the outside of the vacuum and causing the motor shaft to pass through the opening of the pump housing. The shaft seal at the outer casing passage must have a vacuum-tight configuration, for example, which can be achieved by oil sealing the shaft seal. However, such seals are absolutely not suitable for use in oil-free operation. Another structural solution consists in placing the motor rotor separated by a partition in a vacuum while the motor stator is placed outside the partition either outside the vacuum or in the atmosphere. However, the separators have to bear the unavoidable electrical technical disadvantages, namely worse efficiency and deteriorating power factor, and the resulting relatively large drive motor and higher heat loss. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a vacuum pump having an electric drive motor that is highly efficient and does not require any shaft seal. According to the present invention, this object can be solved by a vacuum pump having the features of claim 1 of the patent application. According to the vacuum pump of the present invention, the motor stator is disposed in a vacuum-sealed motor casing in a vacuum. In addition, the motor stator was cast into a cast composite made from a suitable casting compound of 200819629. According to the present invention, not only the motor rotor but also the motor stator are disposed in the vacuum space as compared with the motor of a partition member, in other words, it is not required to be hermetically separated from the vacuum transfer portion of the vacuum pump. If desired, the rotor housing has only one opening through which the control of the motor is driven and directed outside the power supply line to the outside of the motor housing. The vacuum tight seal of the fixed portion presented by the control and power supply lines is simpler than the seal of a movable portion relative to a fixed portion, such as a shaft seal. Since the motor rotor and the motor stator are all disposed in a vacuum, the shaft seal can be omitted and the vacuum space of the vacuum pump can be prevented from leaking and a reliable permanent seal. By omitting a spacer, the gap between the motor rotor and the motor stator can be reduced to a minimum required for a construction. Thereby, the efficiency and power factor of the drive motor are significantly improved, respectively. Thereby, in turn, a smaller electric drive motor can be used to produce the same shaft output. Due to the small electromagnetic losses, the heat generated is also considerably improved and reduced, whereby the structure can be further simplified. The motor stator is built into the bell composite, and one or more horse-spindle coil coils are found in the cast-reduced body in any of the examples. Since this is not the case, a flashover voltage is generated between one or more stator coil windings in a vacuum, which is necessary. The cast composite is a good electrical insulator compared to the non-cast composite vacuum. In addition, the cast compound ensures that heat can be carried away because of its thermal conductivity. The bundle of laminations of the motor stator can also be cast completely or partially into the cast composite, but is not necessary. Another important property of the foundry compound of 200819629 is a low gas permeability and good corrosion resistance. The motor stator includes one or more coils and a bundle of laminations, and the one or more coils and the bundle of laminations are cast into the cast composite. According to a preferred embodiment, the cast composite is an epoxy resin. The epoxy resin is a good electrical insulator, has high thermal conductivity and is suitable for casting in a relatively simple manner at a relatively low temperature. According to a preferred embodiment, the cast composite comprises a crucible having a thermal conductivity that is better than the cast composite material. Thereby, the thermal conductivity of the foundry composite is increased so that more heat can be taken away. Preferably, a line passage through the opening of the motor housing is provided and the cast compound has a projection that projects axially into the opening, in other words, along the axis of the drive motor and the pump rotor. The protruding portion is integrally formed with the casting compound of the cast composite. The lines and other lines for supplying power to the drive motor are axially disposed in the projections as much as possible, if necessary. The vacuum tight seal of the passage is formed between the projection of the cast composite and the edge of the opening by a suitable sealing means, such as by a rubber elastic jaw ring. However, the actual vacuum hermetic seal is also affected by the separation opening cover which is sequentially sealed by the rubber elastic jaw ring with respect to the edge of the motor housing opening and includes suitable contact pins for the passage. Preferably, the drive motor is a brushless DC or non-synchronous motor. Since it is brushless, this type of motor is particularly suitable as a drive motor for a vacuum pump. According to a preferred embodiment, the vacuum system is a Roots vacuum 200819629 pump. Due to its construction, the parts that drive the motor or drive the motor are usually placed on the vacuum side of the Rös s vacuum pump, which results in the need for a vacuum tight seal of the drive motor, in particular for Roots vacuum pumps. [Embodiment] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In Fig. 1, a Roots vacuum pump 10 is illustrated in the form of a longitudinal region and includes, among other things, an electric drive motor 1, a first pump rotor 14 and two bearings 16 formed as rolling bearings. 1, 18. One of the bearings 1 8 of the two rolling bearings is axially disposed between the pump rotor 14 and the drive motor 12. A second pump rotor that mates with the first pump rotor is not depicted. Essentially, the outer casing 19 of the vacuum pump 10 is comprised of a transmission housing 20, a pump housing 22 and a motor housing 24. A drive motor 12 formed by a motor stator 28 and a motor rotor 30 mounted on the shaft 32 is disposed in a vacuum-sealed metal motor casing 24. The drive motor 12 is a brushless DC motor, but can also be constructed as a brushless asynchronous motor. In any example, the drive motor 12 has a brushless configuration. The entire vacuum pump housing 19 has a vacuum-tight configuration. In particular, the motor housing 24 has a vacuum-tight configuration. Therefore, approximately the same gas pressure as that at the adjacent end of the pump rotor 14 is generated in the motor casing 24. This is necessary, among other things, to avoid airflow from the motor casing 24 towards the pump rotor 14, which may undesirably transfer lubricating oil from the motor casing 24 to the pump area. A seal arrangement 34 is provided between the motor side bearing 18 and the pump rotor 14 and is substantially a lubricating oil seal and prevents the lubricating oil 4 200819629 from entering the pump housing 22 from the motor housing 24. On a stack 40, the motor stator 28 includes a plurality of coils 42. The motor stator 28 formed by the bundle slab 40 and the coil 42 is completely prayed into the drawing composite 43 of the composite 44. Therefore, the cast composite 4 3 forms a closed loop. The foundry composite 4 4 is composed of an epoxy resin and comprises a ruthenium charge having a thermal conductivity better than that of the cast composite material. Electromagnetic neutral materials such as sand are particularly suitable as the ruthenium charge. In Fig. 2, the line passage ^ 46 through the axial motor housing opening 48 is illustrated on an enlarged scale. The cast compound projection 6 〇 axially projects into the opening 48 and over a portion of the length of the opening. The opening 48 and the projection 60 are axially disposed, in other words, parallel to the axis of the drive motor. The actual vacuum tight seal is affected by the lid ό 2 sealed by the beak ring 64 relative to the outer casing 24. One or more of the contact pins 5 接通 are electrically connected to the wire 50, and are cast in the cover 62. The wire 50 acts to supply power to the motor stator 28 to the magnetic bearings and, if desired, to the sensor data. [Simple description of the drawing] w Figure 1 shows the longitudinal direction of the Roots vacuum pump; and Figure 2 shows the line channel of the vacuum pump of Figure 1. [Main component symbol description] 10 Vacuum pump 12 Electric drive motor 14 Pump rotor 16 Bearing 18 Bearing 200819629 19 Housing 20 Drive housing 22 Pump housing 24 Motor housing 28 Motor stator 30 Motor rotor 32 Shaft 34 Seal configuration 40 Lamination 42 Coil 43 Casting Composite 44 Casting compound 46 Line channel 48 Opening 50 Wire 50? Contact pin 60 Tab 62 Cover 64 Ring