Patent ID: 7862231
Filing Date: 2011-01-04
Classification: G01K

Abstract:
1. An apparatus for testing temperature comprising a plurality of thermo-couples, a plurality of relays, a ground circuit, a compensation circuit, a power supply circuit, a switch circuit, and a micro processor unit (MPU), the thermo-couples configured for sampling temperature at different locations in the CNC machine, the thermo-couples connected to a corresponding relay and selectively connected to the switch circuit by turning on or off the corresponding relay, the compensation circuit comprising a cold junction compensator and a first relay, the ground circuit comprising a ground terminal and a second relay, the power circuit comprising a power supply and a third relay, the first, second, and third relays selectively connected the cold junction compensator, the ground terminal, the power supply to the switch circuit, the switch circuit comprising a capacitor and a fourth relay, the fourth relay selectively connected to the MPU, the ground circuit, the compensation circuit, or the power supply circuit to the capacitor, the MPU configured for obtaining a voltage at the capacitor, and converting the voltage to a temperature signal.