Vacuum pump system and method for operating a vacuum pump system

Abstract

A vacuum pump system is provided that includes 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 vacuum pump connected to an outlet 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, wherein the predetermined control variable for the sealing gas device is a characteristic value of an electric motor driving the main vacuum pump, wherein the characteristic value is a power consumption.

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 the predetermined control variable or a different control variable.

3. The vacuum pump system according to claim 1, further comprising a second predetermined control variable for the sealing gas device that comprises the entering or terminating of a standby mode.

4. The vacuum pump system according to claim 1, further comprising a second predetermined control variable for the sealing gas device that comprises the falling below a pressure value at an inlet of the main vacuum pump, which pressure value is determined with the aid of a pressure sensor, wherein the pressure value is 1 mbar.

5. The vacuum pump system according to claim 1, further comprising a second predetermined control variable for the sealing gas device that comprises the falling below a pressure value at an outlet of the main vacuum pump, which pressure value is determined with the aid of a pressure sensor, wherein the pressure value is 1020 mbar.

6. The vacuum pump system according to claim 1, wherein the control device comprises an electrically switchable valve, wherein the electrically switchable valve is arranged upstream of the auxiliary vacuum pump.

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

8. The vacuum pump system according to claim 1, further comprising a check valve provided at an outlet of the main vacuum pump, further comprising a second predetermined control variable for the sealing gas device that comprises a position of the check valve.

9. A method for operating a vacuum pump system according to claim 1, wherein said method comprises: evacuating the chamber via at least the main vacuum pump; and switching the sealing gas supply device off and on with the aid of the control device as a function of the predetermined control variable.

10. The method according to claim 9, further comprising switching the auxiliary vacuum pump off and on as a function of the predetermined control variable or a different control variable.

11. The method according to claim 9, further comprising using, as a second predetermined control variable, a step of an entering or a terminating of a standby mode.

12. The method according to claim 9, further comprising using, as a second predetermined control variable, a pressure value at an inlet of the main vacuum pump, wherein the pressure value is 1 mbar.

13. The method according to claim 9, further comprising using, as a second predetermined control variable, a pressure value at an outlet of the main vacuum pump, wherein the pressure value is 1020 mbar.

14. The method according to claim 9, further comprising controlling, with the aid of the control device, a valve arranged upstream of the auxiliary pump.

15. The method according to claim 9, further comprising controlling, with the aid of the control device, a valve arranged in a supply line for the sealing gas supply device.

16. The method according to claim 9, further comprising using, as a second predetermined control variable, a position of a check valve provided at an outlet of the main vacuum pump.

17. A vacuum pump system comprising: a main vacuum pump adapted to be connected to a chamber to be evacuated; an auxiliary vacuum pump connected to an outlet of said main vacuum pump; a sealing gas supply device; 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 evacuating the chamber via at least the main vacuum pump; switching the sealing gas supply device off and on with the aid of the control device as a function of the predetermined control variable; and using, as the predetermined control variable, a characteristic variable of an electric motor driving the main vacuum pump.

18. The method according to claim 17, further comprising switching the auxiliary vacuum pump off and on as a function of the predetermined control variable or a different control variable.

19. The method according to claim 17, further comprising controlling, with the aid of the control device, a valve arranged in a supply line for the sealing gas supply device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Hereunder the disclosure is explained in detail on the basis of a preferred embodiment with reference to the accompanying drawing in which:

(2) The FIGURE shows a schematic diagram of a vacuum pump system including a control device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(3) 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.

(4) 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.

(5) 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.