Oil condition sensor

Abstract

An oil condition sensor is proposed which can stably check the degree of contamination of oil with metallic powder. The oil condition sensor includes a cup-shaped electrode and rod-shaped electrodes provided opposite to the cup-shaped electrode. The rod-shaped electrodes are connected to a first power supply through first fixed resistors having a predetermined threshold. The voltage from the first power supply is applied through the respective rod-shaped electrodes to first inputs of respective operational amplifiers. The oil condition sensor further includes a second power supply which produces a voltage applied to second inputs of the respective operational amplifiers. Each operational amplifier is configured to produce a predetermined voltage from its output if the voltage applied to the first input falls below the voltage applied to the second input. The output of each operational amplifier is connected to the second input through a second fixed resistor. Thus, there is a hysteresis relation between the input and output of the amplifiers, so that once an operational amplifier produces a voltage from its output, even if the voltage from the corresponding conductor falls thereafter, the operational amplifier continuously produces a voltage.

Dependencies are inferred from the claim text.