| 摘要 |
<p>An oil level sensor device for sensing and controlling the level of oil in the crankcases of refrigeration compressors, each compressor having a crankcase with a housing for oil that accumulates during the compression operation and each housing having an opening with a prism member mounted in it, the prism members having two angularly relating surfaces exposed to the oil in the crankcase and a light source and a light sensor mounted adjacent to the prism on the outside of the crankcase housing such that the light from each light source impinges on one of the angularly related prism surfaces and is reflected thereby to the second angulary related surface and then back to the light sensor. Each light sensor has an output which is connected to the input of the control circuit which operates to energize a solenoid valve to add oil to the crankcase from a remote source when the oil level in the crankcase as sensed is below a predetermined level. The subject oil level sensor device may include a plurality of vertically arranged light sources and light sensors and the circuit may optionally include a circuit portion responsive to an over filled and an underfilled condition to produce an alarm. The circuit also includes an adjustment device which can be set to establish and maintain any desired oil level in the crankcase. <IMAGE></p> |
