VACUUM PUMP SYSTEM AND METHOD FOR OPERATING A VACUUM PUMP SYSTEM

Abstract

A vacuum pump system comprising a main vacuum pump that is connected to a chamber that is to be evacuated. An auxiliary pump is connected to an outlet of the main vacuum pump. Furthermore, a sealing gas supply device is connected to the main vacuum pump. The sealing gas supply device is switched on and off with the aid of a control device as a function of a predetermined control variable. Additionally, a method for controlling the vacuum pump system.

Claims

1. A vacuum pump system comprising a main vacuum pump adapted to be connected to a chamber to be evacuated, an auxiliary pump connected to an inlet of said main vacuum pump, a sealing gas supply device, and a control device connected to said sealing gas supply device for switching said sealing gas supply device off and on as a function of a predetermined control variable.

2. The vacuum pump system according to claim 1, wherein the control device is connected to the auxiliary vacuum pump for switching said auxiliary vacuum pump off and on as a function of a different or the same control variable.

3. The vacuum pump system according to claim 1, wherein the predetermined control variable for the sealing gas device and/or the auxiliary vacuum pump is the entering or terminating of a standby mode.

4. The vacuum pump system according to claim 1, wherein the predetermined control variable for the sealing gas device and/or the auxiliary vacuum pump is the falling below a pressure value at the inlet of the main vacuum pump, which pressure value is in particular determined with the aid of a pressure sensor, wherein the pressure limit value preferably is 1 mbar.

5. The vacuum pump system according to claim 1, wherein the predetermined control variable for the sealing gas device and/or the auxiliary vacuum pump is the falling below a pressure value at the outlet of the main vacuum pump, which pressure value is in particular determined with the aid of a pressure sensor, wherein the pressure limit value preferably is 1020 mbar.

6. The vacuum pump system according to claim 1, wherein the predetermined control variable for the sealing gas device and/or the auxiliary vacuum pump is a characteristic value of an electric motor driving the main vacuum pump, in particular a power consumption.

7. The vacuum pump system according to claim 1, wherein the control device comprises an electrically switchable valve or is connected to the latter which preferably is arranged upstream of the auxiliary pump.

8. The vacuum pump system according to claim 1, wherein the control device comprises an electrically switchable valve or is connected to the latter which is arranged in a supply line for the sealing gas.

9. The vacuum pump system according to claim 1, wherein the position of a check valve provided at an outlet of the main vacuum pump is used as a control variable.

10. A method for operating a vacuum pump system according to claim 1, wherein said method comprises switching a sealing gas supply device off and on with the aid of a control device as a function of a predetermined control variable.

11. The method for operating a vacuum pump system according to claim 10, wherein in addition to or instead of the sealing gas supply device, the method comprises switching the auxiliary vacuum pump off and on, wherein switching off and on is preferably performed as a function of a different or the same control variable.

12. The method for operating a vacuum pump system according to claim 10, wherein, as the control variable, the entering or terminating of a standby mode is used.

13. The method for operating a vacuum pump system according to any one of claims 10 to 12, wherein, as the control variable, the falling below a pressure value at the inlet of the main vacuum pump is used, wherein the pressure limit value preferably is 1 mbar.

14. The method for operating a vacuum pump system claim 10, wherein, as the control variable, the falling below a pressure value at the outlet of the main vacuum pump is used, wherein the pressure limit value preferably is 1020 mbar.

15. The method for operating a vacuum pump system according to claim 10, wherein, as the control variable, a characteristic variable of an electric motor driving the main vacuum pump, in particular the power consumption, is used.

16. The method for operating a vacuum pump system according to claim 10, wherein, with the aid of the control device, a valve arranged upstream of the auxiliary pump is controlled.

17. The method for operating a vacuum pump system according to claim 10, wherein, with the aid of the control device, a valve arranged in the supply line for the sealing gas is controlled.

18. The method for operating a vacuum pump system according to claim 10, wherein, as the control variable, the position of a check valve provided at the outlet of the main vacuum pump is used.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Hereunder the disclosure is explained in detail on the basis of a preferred embodiment with reference to the accompanying drawing in which:

[0029] FIG. 1 shows a schematic diagram of a vacuum pump system including a control device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0030] In the illustrated exemplary embodiment, the vacuum pump system comprises a main vacuum pump 10. The outlet of the main vacuum pump 10 is connected to an auxiliary vacuum pump 12 which is in particular an ejector pump. The inlet of the main vacuum pump 10 is connected to a chamber 14 to be evacuated. Further, the main vacuum pump 10 has connected thereto a pump 16. The latter is connected to a container 24 via a controllable valve 18, in which container sealing gas is provided. With the aid of the pump 16 sealing gas is thus supplied to the main vacuum pump 10. If the sealing gas is pressurized the pump 16 may be omitted.

[0031] In the illustrated exemplary embodiment, a control device 20 is connected to a pressure sensor 22 arranged between the chamber 14 to be evacuated and the main vacuum chamber 10.

[0032] The pressure measured by the pressure sensor 22 serves as a control variable for the control device 20. The electric valve 18, via which sealing gas is supplied to the main vacuum pump 10, is controlled as a function of the pressure. Further, the ejector pump 12 is controlled correspondingly. Here, too, an electric valve, which controls the propellant gas supply to the ejector pump 12, can be controlled.