An autonomous valve assembly for the regulation, depressurization and elevation of the pressure in pneumatic equipment that presents a valve body 22 and an air regulator body 4 with a compressed air intake 54 connected to a source of compressed air, whereby the body 4 presents two pressure regulators 45, 46 that regulate the pressure at a desired level and communicate it to an air diverter plunger 6 with reciprocating movement to cyclically divert the compressed air to a pressurization plunger assembly 9A, 5, 9B that has a reciprocating movement within a pressure casing 20A, 20B, wherein said air pressure regulators 45, 46 are adjusted to regulate the passage of air to a first pressure and a second pressure.