Patent ID: 7665578

Claim:
An apparatus to prepare a fine oil mist, to feed said oil mist into at least one lubricant duct of at least one tool of a CNC machine tool, comprising: oil-conveying pumps and at least one compressed air conduit to convey air, at least one oil-air mix generator associated with the pumps and the at least one air conduit, the at least one oil-air mix generator processing oil and air into a fine oil mist and feeding it to a tank from which the oil mist is supplied via the at least one lubricant duct of the at least one tool, a pressure sensor measuring the aerosol pressure in the tank and a control unit which initiates an air supply and at least one of two aerosol pumps and an oil over-enriching pump to generate oil-air mixes, and wherein the control unit is responsive to the aerosol pressure and is configured to stop the oil over-enriching pump when a first predetermined supply pressure p 2 has been exceeded, stops at least one aerosol pump when the sensed aerosol pressure exceeds a predetermined, maximum permissible second supply pressure p 4 , starts the at least one aerosol pump when the sensed aerosol pressure decreases below a predetermined third supply pressure p 3 , and starts the an oil over-enriching pump when the sensed aerosol pressure decreases below a predetermined fourth supply pressure p 1 , where p 1 <p 2 <p 3 <p 4 .