Enhanced pressure measurement flow control system

A system for controlling flow of a fluid through a line, the system comprising:

• dispensing means (i) for isolating a region the first fluid in the line from effects of pressure in the line outside of the region, the region having an input and an output for the first fluid, and (ii) for repetitively dispensing into and out of the region volume increments of the fluid;
• source means for containing a first volume of measurement gas;
• reservoir means in communication with the source means for containing a second volume of measurement gas;
• pumping means for moving a quantity of measurement gas between the reservoir means and the source means, thereby producing changes in the pressure of the measurement gas in the reservoir means and in the pressure of the measurement gas contained in the source means;
• a source communication pathway between the source chamber and the isolated region and a reservoir communication pathway between the reservoir chamber and the isolated region, the source communication pathway and the reservoir communication pathway joining to at some point along each respective pathway to form a joint communication pathway leading to the isolated region;
• source valving means for opening and closing the source communication pathway;
• reservoir valving means for opening and closing the reservoir communication pathway;
• the isolated region, the source means and the reservoir means, and the source communication pathway, the reservoir communication pathway and the joint communication pathway being so disposed in relationship with each other such that they together define a fixed volume, and such that a change in volume of the fluid in the isolated region produces a correlative change in the joint communication pathway and in any other enclosure in pressure communication with the joint communication pathway;
• pressure transducing means (i) in pressure communication with the source means for generating data relating to the pressure of the measurement gas in the source means, and in any other enclosure in pressure communication with the source means and (ii) in pressure communication with the joint communication pathway for generating data relating to the pressure of the measurement gas in the joint communication pathway, and in any other enclosure in pressure communication with the joint communication pathway;
• and
• control means, in communication with the pressure monitoring means, the pumping means, the dispensing means, the source valving means, and the reservoir valving means, for causing the dispensing means to dispense first fluid in determinable increments based on data from the pressure monitoring means taken at predetermined points during a calibration and dispensing cycle.

A method for controlling flow of a fluid through a line, the method comprising the following steps:

• (i) providing in the line a region that can be selectably isolated from effects of pressure in the line outside of the region;
• (ii) housing a source volume of measurement gas in communication with the region such that the region and the source volume occupy a fixed volume, such that a change of volume of fluid in the region produces a complementary change in the volume of the source volume, with a resulting change in the pressure in the source volume;
• (iii) housing a constant reservoir volume of measurement gas in communication with the source volume, such that moving a quantity of measurement gas between the reservoir volume and the source volume produces corresponding changes in the pressure in the source volume and in the reservoir volume;
• (v) providing means for generating on a continual basis data relating to the pressure in the source volume and in the reservoir volume;
• and
• (vi) causing fluid to be dispensed through the line in determinable increments based on pressure data generated at predetermined points during a calibration and dispensing cycle.

A method for controlling flow of fluid through a line the method comprising:

• (i) providing in the line a region that can be selectably isolated from effects of pressure in the line outside of the region;
• (ii) housing a common volume of measurement gas in communication with the region;
• (iii) housing a source volume of measurement gas that can be selectably put in communication with the common volume such that the region, the common volume and the source volume together define a fixed volume, such that a change of volume of fluid in the region produces a complementary change in the volume of the common volume with a resulting change in the pressure of the measurement gas in the source volume;
• (iv) housing a reservoir volume of measurement gas that can be selectably put in communication with the common volume such that the region, the common volume and the reservoir volume together define a fixed volume, such that a change of volume of fluid in the region produces a complementary change in the volume of the common volume with a resulting change in the pressure of the measurement gas in the reservoir volume;
• (v) providing a means for moving a quantity of measurement gas between the reservoir volume and the source volume, thereby producing changes in the pressure in the source volume and in the reservoir volume;
• (vi) providing means for generating on a continual basis data relating to the pressure of in the source volume and in the reservoir volume;
• and
• (vii) causing fluid to be dispensed through the line in determinable increments based on pressure data generated at predetermined points during a calibration and dispensing cycle.

An improved system for controlling the flow of fluid through a line of the type including a region in the line that can be selectably isolated from pressure effects in the line outside of the region by microprocessor-controlled input and output valves, wherein the improvement comprises:

• source means for containing a variable volume of measurement gas in communication with the region, such that the source means and the region, when isolated, together define a fixed volume, and such that a change in volume of the fluid in the region produces a complementary change in the volume of the measurement gas in the source means with a resulting change in the pressure in the source means;
• reservoir means in communication with the source means for containing a fixed volume of measurement gas;
• pumping means for moving a quantity of measurement gas between the reservoir means and the source means;
• and
• pressure monitoring means for generating source means measurement gas pressure data and reservoir means measurement gas pressure data during a calibration and dispensing cycle.

An improved system for controlling the flow of fluid through a line of the type including a region in the line that can be selectably isolated from pressure effects in the line outside of the region by microprocessor-controlled input and output valves, wherein the improvement comprises:

• common means for containing a variable volume of measurement gas in communication with the region, such that the common volume and the region, when isolated, together define a fixed volume, such that a change in the volume of the fluid in the region produces a complementary change in the volume of the measurement gas in the common volume with a resulting change in the pressure in the common means;
• source means for containing a known volume of measurement gas;
• reservoir means for containing a known volume of measurement gas;
• pumping means for moving a quantity of measurement gas between the reservoir means and the source means;
• source valving means for selectably permitting communication between the common means and the source means;
• reservoir valving means for selectably permitting communication between the common means and the reservoir means;
• and
• pressure monitoring means for generating source means measurement gas pressure data and reservoir means measurement gas pressure data during a calibration and dispensing cycle.