Monitoring device and method of an oil flow mixed with air

A method for detecting the flow of air/oil inside a tubular element comprising the steps of:

• providing the tubular element coupled with at least one first and one second photoelectric sensor, each of the first and the second photoelectric sensor comprising one emitter of a radiation and one receiver, the emitter directly or indirectly facing the receiver, wherein the first optical line is aligned to a first diameter of the tubular element and the second optical line is aligned to a second diameter of the tubular element, the first and the second diameter being mutually angled in a sectional view of the tubular element,
• obtaining a first parameter indicative of an amount of oil present in the tubular element detected by the first photoelectric sensor with a first optical line,
• obtaining a second parameter related to the amount of oil present in the tubular element detected by the second photoelectric sensor with a second optical line radially angled from the first optical line with respect to the tubular element,
• determining the presence or the absence of an air/oil flow in the tubular element based on the first and/or second parameter.

An oil flow monitoring device suitable to monitor a minimal oil flow mixed with air, comprising

• a tubular element coupled with a first photoelectric sensor and a second photoelectric sensor,
• wherein the first photoelectric sensor comprises a first emitter of a radiation and a first receiver, the first emitter directly or indirectly facing the first receiver,
• wherein the second photoelectric sensor comprises a second emitter of a radiation and a second receiver, the second emitter directly or indirectly facing the second receiver,
• the first and the second photoelectric sensors having a first and a second optical line respectively, the tubular element being at least partially transparent to said radiation,
• the first and the second photoelectric sensor being mounted on the tubular element so that the first optical line and the second optical line are radially angled with respect to the tubular element,
• wherein the first optical line and a longitudinal axis of the tubular element lie on a first phantom plane and the second optical line and a longitudinal axis of the tubular element lie on a second phantom plane.