Pressure-filling of containers

Abstract

A method of pressure-filling a container includes placing its opening tightly against a filling element, extending a return gas tube into the container, causing and measuring a progression of pressures in the container's interior, thereby generating a measured progression of pressures, generating a signal indicative of the measured progression of pressures, recording it, monitoring it for information indicative of a pressure peak, identifying such information, comparing a measured value of the pressure peak with a reference value, measuring an absolute pressure at a point in time at which the pressure peak is measured, based at least in part this measurement, determining that the pressure peak is caused by the filling-material level having reached the return gas tube, and upon making the determination, transmitting closing the filling element.

Having described the invention, and a preferred embodiment thereof, what is claimed as new, and secured by Letters Patent is: 
     
         1 - 7 . (canceled) 
     
     
         8 . A method of pressure-filling a container, said method comprising placing said container's opening tightly against a filling element, extending a return gas tube into said container, causing a progression of pressures in said container's interior, measuring said progression of pressures in said container's interior, thereby generating a measured progression of pressures, generating an electrical signal indicative of said measured progression of pressures, recording said electrical signal, thereby generating a recorded electrical signal, monitoring said recorded electrical signal for information indicative of a pressure peak, identifying information indicative of a pressure peak, comparing a measured value of said pressure peak with a reference value, measuring an absolute pressure at a point in time at which said pressure peak is measured, based at least in part on said absolute pressure, determining that said pressure peak is caused by a filling-material level having reached said return gas tube, and upon making said determination, transmitting a closing signal to close said filling element. 
     
     
         9 . The method of  claim 8 , wherein monitoring said recorded electrical signal for information indicative of a pressure peak comprises monitoring said recorded electrical signal for sufficient time to provide pressure measurements over a period of between one-tenth of a second and three seconds, said pressure measurements to be used for detection of said pressure peak. 
     
     
         10 . The method of  claim 8 , wherein identifying information indicative of a pressure peak comprises, for each pressure measurement in a set of pressure measurements, determining a difference between said pressure measurement and an average of pressure measurements and comparing said difference with a reference value, wherein said set of pressure measurements comprises a set of between five and fifty preceding pressure measurements and said average of pressure measurements is an average of pressure measurements from a preceding one to three seconds. 
     
     
         11 . The method of  claim 8 , wherein identifying information indicative of a pressure peak comprises identifying a pressure differential between a foot of said pressure peak and a vertex of said pressure peak, and using said pressure differential as a basis for determining that said pressure peak is caused by said filling-material level having reached said return gas tube. 
     
     
         12 . The method of  claim 8 , further comprising selecting said container to be a container having a cross-section that decreases with increasing distance from a base of said container, and causing filling of said container to transition from a rapid filling process to a slow filling process, said transition corresponding to a point on said progression of pressures, wherein determining that said pressure peak is caused by said filling-material level having reached said return gas tube comprises doing so based only on pressures in said pressure progression that are after said point. 
     
     
         13 . The method of  claim 8 , wherein determining that said pressure peak is caused by said filling-material level having reached said return gas tube comprises doing so at least in part on the basis of a time at which said candidate pressure peak occurs in said measured progression of pressures. 
     
     
         14 . The method of  claim 8 , wherein causing a progression of pressures in said container's interior comprises pre-charging said container with an inert gas prior to entry of liquid-filling material into said container.