Vacuum pump

Abstract

A vacuum pump that is connectable to an external system and configured to evacuate material from the external system. The vacuum pump including a motor operable in a first mode and a second mode that is slower than the first mode, a pump assembly driven by the motor and is lubricated and cooled by a lubricant, and a temperature sensor outputting a temperature signal corresponding to a temperature of the lubricant. The vacuum pump further includes an electronic control unit configured to receive the temperature signal from the temperature sensor, determine an electrical current value being drawn from the motor, operate the motor in the second mode when the temperature signal is below a temperature threshold, maintain the motor in the second mode while the electrical current value is above a current threshold, and operate the motor in the first mode only after the electrical current value remains below the current threshold for a preset time period.

Dependencies are inferred from the claim text.