Filling machine including two-stage actuator for filling valve

A filling system, comprising:

• a filling valve including an outlet opening and an axially movable plunger having a sealing end movable relative to the outlet opening between an outlet closing position, an outlet fully open position and at least one outlet partially open position;
• a pneumatic actuator operatively connected to move the plunger, the pneumatic actuator including:
• a cylinder housing;
• an upper piston assembly movable along the cylinder housing between a down position and an up position, and
• a lower piston assembly movable along the cylinder housing between a down position and at least a first up position and a second up position,
• wherein the first and second up positions of the lower piston assembly are defined by contact with a lower portion of the upper piston assembly to establish (i) the first up position of the lower piston assembly when the upper piston assembly is in its down position and (ii) the second up position of the lower piston assembly when the upper piston assembly is in its up position;
• a first port through the cylinder housing for selectively pressurizing a lower pressure action surface area of the lower piston assembly and a second port through the cylinder housing for selectively pressurizing an upper pressure action surface area of the lower piston assembly;
• a third port through the cylinder housing for selectively pressurizing a lower pressure action surface area of the upper piston assembly and a fourth port through the cylinder housing for selectively pressurizing an upper pressure action surface area of the upper piston assembly;
• and
• a fixed sealing member located within the cylinder housing to sealingly separate the upper pressure action surface area of the lower piston assembly from the lower pressure action surface area of the upper piston assembly.

A filling system, comprising:

• a filling valve including an outlet opening and an axially movable plunger having a sealing end movable relative to the outlet opening between an outlet closing position, an outlet fully open position and at least one outlet partially open position;
• a pneumatic actuator operatively connected to move the plunger, the pneumatic actuator including:
• a cylinder housing;
• an upper piston assembly movable along the cylinder housing between a down position and an up position, and
• a lower piston assembly movable along the cylinder housing between a down position and at least a first up position and a second up position,
• wherein the first and second up positions of the lower piston assembly are defined by contact with a lower portion of the upper piston assembly to establish (i) the first up position of the lower piston assembly when the upper piston assembly is in its down position and (ii) the second up position of the lower piston assembly when the upper piston assembly is in its up position;
• a first port through the cylinder housing for selectively pressurizing a lower pressure action surface area of the lower piston assembly and a second port through the cylinder housing for selectively pressurizing an upper pressure action surface area of the lower piston assembly;
• a third port through the cylinder housing for selectively pressurizing a lower pressure action surface area of the upper piston assembly and a fourth port through the cylinder housing for selectively pressurizing an upper pressure action surface area of the upper piston assembly;
• and
• a fixed sealing member located within the cylinder housing to sealingly separate the upper pressure action surface area of the lower piston assembly from the lower pressure action surface area of the upper piston assembly;
• wherein a part of the upper piston assembly passes through the sealing member to place the lower portion of the upper piston assembly below the fixed sealing member.