Electrical generator or motor structure – Dynamoelectric – Rotary
Patent
1998-02-23
1999-08-17
Enad, Elvin G.
Electrical generator or motor structure
Dynamoelectric
Rotary
310 87, 310 90, 310 905, 310156, 310261, 310266, 310267, H02K 112
Patent
active
059398132
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a gap tube motor including a gap tube arranged between a rotor and stator.
2. Description of the Prior Art
In pumps, for example, for aggressive liquids or for water of highest purity, a complete separation between the drive motor and the pump is required. It is known to use a gap tube motor or canned motor, which has a gap tube arranged between the stator and the rotor, for applications of this kind. It is known to suspend the rotor of a gap tube motor hydrostatically or by means of a sliding bearing. A gap tube motor having a sliding bearing has, for example, the disadvantage that abrasive substances contained in the liquid can already destroy the sliding bearing after a short operating period. In addition, the liquid can be contaminated by the particles of the sliding bearing. A gap tube motor having a hydrostatic bearing has, for example, poor dry running properties. Moreover, liquids with volatile substances, i.e. liquids with gas components, can be forwarded only poorly.
SUMMARY OF THE INVENTION
The object of the present invention is to provide an economically more advantageous gap tube motor.
This object is satisfied by a gap tube motor in accordance with the features of claim 1. The subordinate claims 2 to 8 relate to further advantageous embodiments of the invention.
The object is satisfied, in particular, in that the gap tube motor comprises a rotor, a stator and a gap tube which is arranged between the rotor and the stator; in that at least two bearing apparatuses are arranged at a spacing in an axial direction with respect to the rotor; and in that at least one of the bearing apparatuses is formed as a bearing and drive apparatus and comprises both an electric motor drive apparatus and a magnetic bearing apparatus in order to both drive the rotor and to journal it in the radial direction without contact using this bearing and drive apparatus.
In an advantageous embodiment of the gap tube motor, the latter is connected to a forwarding apparatus for a fluid, in particular to a centrifugal pump. In a further advantageous embodiment, the rotor of the gap tube motor is magnetically journalled without contact by at least two magnetic bearing apparatuses which are arranged with a spacing in the axial direction. In a further advantageous embodiment, the one magnetic bearing apparatus of the gap tube motor is designed as a bearing and drive apparatus comprising an electric motor drive apparatus and a magnetic bearing apparatus. In a particularly advantageous embodiment, the bearing and drive apparatus of the gap tube motor is designed as a bearing-less motor with a motor winding which is arranged in the stator and a control winding which is arranged in the stator, with the motor winding having a number of pole pairs p and the control winding having a number of pole pairs p.+-.1.
An advantage of the gap tube motor in accordance with the invention is to be seen in the fact that the rotor can be designed with purely passively operating components and in that the coils which magnetically journal or magnetically drive the rotor are arranged so that they are separated from the rotor by a gap tube. The rotor is thereby magnetically journalled without contact and the space surrounding the rotor is hermetically separated by the gap tube with respect to the stator. In this way a gap tube pump can be manufactured having a rotor which is journalled without contact and in which the space surrounding the rotor is hermetically separated from the stator by the gap tube. Through this hermetic separation, the gap tube pump in accordance with the invention is suitable, in particular, for the forwarding of substances of high purity such as water or enzymes of biochemical processes. Abrasive substances containing chemicals can also be forwarded using the gap tube pump in accordance with the invention, since the rotor is journalled without contact and thus the abrasive substances can not damage the bearing apparatus. The gap tube pump in accor
REFERENCES:
patent: 3572982 (1971-03-01), Kozdon
patent: 4779614 (1988-10-01), Moise
patent: 4908012 (1990-03-01), Moise et al.
patent: 4988906 (1991-01-01), Littlefield
patent: 5059092 (1991-10-01), Kabelitz et al.
patent: 5127792 (1992-07-01), Katsuta et al.
patent: 5288213 (1994-02-01), Nasr
patent: 5308229 (1994-05-01), Dupuis et al.
patent: 5494413 (1996-02-01), Campen et al.
patent: 5567132 (1996-10-01), Dupuis et al.
Chiba, et al., "An Analysis of Bearingless AC Motors" in: IEEE Transactions on Energy Conversion, vol. 9, No. 1, 1994, New York, US, pp. 61-68.
Patent Abstracts of Japan, vol. 18, No. 355 (E-1573), Jul. 5, 1994 & JP,A,06 090545 (Ebara Corporation), Mar. 29, 1994. Abstract.
Enad Elvin G.
Lust Antriebstechnik GmbH
Sulzer Electronics AG
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