POWER SUPPLY SYSTEM FOR A VACUUM PUMP AND VACUUM PUMP

Abstract

A power supply system for vacuum pump comprising a power supply means to supply electrical energy to the vacuum pump for operation and energy storage means connected to the vacuum pump to store energy produced by the vacuum pump during ramp-down of the vacuum pump.

Claims

1. A power supply system for a vacuum pump comprising: a power supply means to supply electrical energy to the vacuum pump for operation; and an energy storage means connected to the power supply means or a motor controller to store energy transferred from the vacuum pump during ramp-down of the vacuum pump.

2. The power supply system according to claim 1, characterized in that energy stored in the energy storage means is used during ramp-up of the vacuum pump.

3. The power supply system according to claim 1, characterized in that the energy in the energy storage means is stored electrically, mechanically, chemically and/or thermally.

4. The power supply system according to claim 1, characterized in that the energy storage means comprises a battery, a capacitor, a pressure vessel, a fuel cell or a flywheel.

5. The power supply system according to claim 1, characterized in that the electrical energy provided to the vacuum pump is completely supplied by the energy storage means.

6. A turbomolecular pump, comprising: a stator; a rotating assembly rotated relatively to the stator by an electric motor, wherein the rotating assembly comprises at least one rotor element in order to convey a gas from a pump inlet towards a pump outlet; a controller connected to the electric motor; and a power supply system connected with the controller; characterized by an energy storage means connected either to the power supply system or the controller to store energy transferred from the vacuum pump during ramp-down of the vacuum pump.

7. A method for shutting-down a vacuum pump, wherein a power supply means is switched off and energy produced by the vacuum pump after switching of the power supply means is stored in energy storage means.

8. The method of claim 7 further comprising starting-up the vacuum pump, wherein the power supply means is switched on and electrical energy of the power supply means is combined with energy generated by the energy storage means.

9. (canceled)

Description

BRIEF DESCRIPTION OF THE FIGURES

[0020] Exemplary embodiments of the invention will be explained in detail with reference to the accompanied drawings.

In the Figures:

[0021] FIG. 1 shows a vacuum pump with a power supply system in accordance with the present invention during ramp-down procedure,

[0022] FIG. 2 shows the same vacuum pump of FIG. 1 during ramp-up procedure and

[0023] FIG. 3 shows another embodiment o present invention.

DETAILED DESCRIPTION

[0024] The inventive vacuum pump 11 comprises a stator 10 with several stator elements 12, a rotor 14 with several rotor elements 16, whereby the rotor 14 and the rotor elements 16 are rotated relatively to the stator 10. The rotor 14 is driven by an electric motor 18, which is connected via a motor controller 20 with a power supply 22. The motor controller 20 controls operation of the vacuum pump 11, i. e. initiates ramp-down and ramp-up procedures. In the present example the energy storage means is built as battery but different energy storage means can be used analogously. The battery 24 is connected with the power supply 22. In the present example the power supply means is mains electricity but different power supply means, eg a battery or uninterruptable power supply, can be used analogously. If the motor controller 20 initiates a ramp-down procedure, the power supply 22 is switched off. Due to initial force, the rotor 14 and the rotor elements 16 are rotating further. This rotation induces a current into the windings of the electric motor 18, thereby converting the rotational energy of the rotor 14 into electrical energy. The energy produced is then transferred to the battery 24 as indicated by the arrows 26 and stored by the battery 24. Due to the withdrawal of energy from the rotor 14 in form of electrical energy, the ramp-down time is decreased.

[0025] During ramp-up or start-up of the vacuum pump 11 (shown in FIG. 2) the motor controller 20 initiates the start-up procedure. Thereby, in FIG. 1 same or similar elements are indicated by the same reference numbers. Upon initiating the vacuum pump start-up the power supply 22 is switched on, as indicated by the arrow 28. In order to decrease the ramp-up time energy stored in the battery 24 is combined with the electrical energy of the power supply 22. The combined energy of the battery 24 and the power supply 22 is then fed to the electrical motor 18, as indicated by the arrows 30, in order to accelerate the rotor elements 16. Thus, the ramp-up time is shortened compared to the ramp-up time with only the power supply 22. Hence, the requirements for the power supply 22 are reduced and a smaller power supply system 22 can be chosen, thereby reducing the costs of the system while enabling short pump cycling times.

[0026] Additionally, it would also be possible to operate the vacuum pump 11 completely by the, battery 24, if the power supply 22 is not able to provide electrical energy to the electric motor 18 due to power cuts or if the power supply 22 is temporarily not connected to the mains power supply. This is in particular possible, if the power supply 22 is temporarily disconnected from the mains power supply when the vacuum pump 11 is at full running speed running. If the vacuum pump 11 is at full running speed, only a small amount of power is required in order to maintain the vacuum pump 11 in the operation condition. This amount of power can he completely provided by the battery 24 if the battery is of appropriate capacity.

[0027] Hence, by the present invention, energy generated by the vacuum pump 11 during the ramp-down procedure is stored by a power storing means. This stored energy can be used during the ramp-up procedure in addition to the general power supply. Thus, the ramp-down time and also the ramp--up time for the vacuum pump 11 are decreased leading to shorter pump cycles providing the customer with a more convenient handling and an enhanced efficiency by use of the vacuum pump 11 in accordance with the present invention.

[0028] FIG. 3 shows another embodiment of the present invention, wherein same or similar elements are indicated by the same reference sign. In contrast to the embodiment of FIGS. 1 and 2, the energy storage means also built as battery 24 is directly connected to the controller, rather than connected to the power supply means. However, the functionality is the same, such that during ramp-down of the vacuum pump 11, rotational energy is transferred to the battery 24 as indicated by arrows 26. The stored energy can be used to accelerate the ramp-up procedure of the vacuum pump 11. Thus, preferably the energy storage means is built separate of the power supply means connected and/or disconnected from the controller independently from whether a power supply means is connected. Replacement of the battery 24 or uses of the vacuum pump without power supply means at least temporarily is possible.

[0029] Although elements have been shown or described as separate embodiments above, portions of each embodiment may be combined with all or part of other embodiments described above.

[0030] Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are described as example forms of implementing the claims.