Apparatus and method for assessing the liquid flow performances through a small dispensing orifice
First Claim
1. A method for assessing the liquid flow performance for dispensing liquid through a relatively small diameter dispensing orifice fluidly coupled to a communication passageway of a precision, low volume, liquid handling system, the method comprising:
- emitting an optical beam of a sensor assembly, from a position outboard from one side of the dispensing orifice, along an optical path extending substantially laterally across and downstream from the dispensing orifice of the liquid handling system prior to dispensing liquid from the dispensing orifice;
continuously sensing the optical beam along the optical path, from a position outboard from an opposite side of the dispensing orifice;
flowing the dispensing liquid through the communication passageway generally sufficient to eject at least a drop of dispensing liquid from the dispensing orifice, and across the optical path of the optical beam; and
adjusting the sensitivity of the sensor assembly so that the drop of dispensed liquid from the dispensing orifice is more “
visible”
to the sensor assembly, wherein;
detecting the drop indicates a flow condition of the dispensing fluid through the dispensing orifice; and
whereinnot detecting the drop indicates a non-flow condition of the dispensing fluid through the dispensing orifice.
6 Assignments
0 Petitions
Accused Products
Abstract
A universal calibration apparatus and method to estimate the dispense output from a low volume, non-contact, liquid dispensing systems that may be applied for every hardware configuration (e.g., tube length, orifice diameter, tip design, etc), reagent solution property and environmental condition. This same calibration technique is applied to calibrate or tune these non-contact liquid dispensing systems to dispense desired volumes (in the range of about 0.050 μL to 50 μL), irrespective of the hardware configuration or the solution properties. That is, the calibration technique is not dependent on any variables, but the result (the actual dispense volume) is dependant on the variable mentioned. By actuating selected pulse widths, and measuring the resulting volume, a Calibration Profile can be generated correlating the liquid volume dispensed from the orifice to the respective pulse width of the dispensing valve thereof through calibration points. In particular, one is selected to deliver a first volume of liquid that is less than a lower base pulse width correlating to the lowest volume of the selected range of volumes of liquid, while a second pulse width is selected to deliver a second volume of liquid dispensed that is greater than an upper ceiling pulse width correlating to the highest volume of the selected range of volumes of liquid. Intermediary pulse widths are also applied, each selected to deliver a different, spaced-apart, respective intermediary low volumes of liquid dispensed from the dispensing orifice between the first volume and the second volume. Thus, applying the Calibration Profile, the pulse widths correlating to the one or more targeted discrete volumes for liquid dispensing can be extrapolated.
85 Citations
26 Claims
-
1. A method for assessing the liquid flow performance for dispensing liquid through a relatively small diameter dispensing orifice fluidly coupled to a communication passageway of a precision, low volume, liquid handling system, the method comprising:
-
emitting an optical beam of a sensor assembly, from a position outboard from one side of the dispensing orifice, along an optical path extending substantially laterally across and downstream from the dispensing orifice of the liquid handling system prior to dispensing liquid from the dispensing orifice; continuously sensing the optical beam along the optical path, from a position outboard from an opposite side of the dispensing orifice; flowing the dispensing liquid through the communication passageway generally sufficient to eject at least a drop of dispensing liquid from the dispensing orifice, and across the optical path of the optical beam; and adjusting the sensitivity of the sensor assembly so that the drop of dispensed liquid from the dispensing orifice is more “
visible”
to the sensor assembly, wherein;detecting the drop indicates a flow condition of the dispensing fluid through the dispensing orifice; and
whereinnot detecting the drop indicates a non-flow condition of the dispensing fluid through the dispensing orifice. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A method for assessing the operational flow condition for dispensing liquids through a plurality of relatively small diameter dispensing orifices aligned in a substantially linear array and each fluidly coupled to a respective communication passageway of a precision, low volume, liquid handling system, the method comprising:
-
(a) emitting an optical beam of a sensor assembly, from a position outboard from one side of the linear array of the dispensing orifices, along an optical path extending substantially along a longitudinal axis of the linear array, and substantially laterally across and downstream from each dispensing orifice of the liquid handling system prior to dispensing liquid from any one of the dispensing orifice; (b) continuously sensing the optical beam along the optical path, from a position outboard from an opposite side of the linear array of the dispensing orifices; (c) flowing the dispensing liquid through a respective communication passageway generally sufficient to eject at least a drop of dispensing liquid from one of the dispensing orifices, and across the optical path of the optical beam, wherein; (d) detecting the drop indicates a flow condition of the dispensing fluid through the one dispensing orifice, said detecting the drop includes adjusting the sensitivity of the sensor assembly so that the respective drop of dispensed liquid from the respective dispensing orifice is more “
visible”
to the sensor assembly; and
wherein(e) not detecting the drop indicates a non-flow condition of the dispensing fluid through the one dispensing orifice; and (f) sequentially repeating events (c)–
(e) for the remaining dispensing orifices to assess the operational flow condition for the entire array of dispensing orifices. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. A sensor assembly for assessing the liquid flow performance for dispensing liquid through a relatively small diameter dispensing orifice fluidly coupled to a communication passageway of a precision, low volume, liquid handling system, said liquid handling system being configured to flow the dispensing liquid through the communication passageway in a manner generally sufficient to eject at least a drop of dispensing liquid from the dispensing orifice, the sensor assembly comprising:
-
an optical emitter component positioned outboard from one side of the dispensing orifice and configured to emit an optical beam along an optical path extending substantially laterally across and downstream from the dispensing orifice of the liquid handling system prior to dispensing liquid from the dispensing orifice; a receiving component positioned outboard from an opposite side of the dispensing orifice, and configured to continuously sense the optical beam along the optical path; a sensitivity adjustment device cooperating between the optical emitter component and the receiving component to adjust the sensitivity of the sensor assembly so that the drop of dispensed liquid from the dispensing orifice passing across the optical path of the optical beam is more “
visible”
to the sensor assembly, wherein;when the drop is detected, a flow condition of the dispensing fluid through the dispensing orifice is indicated; and
whereinwhen the drop is not detected, a non-flow condition of the dispensing fluid through the dispensing orifice is indicated. - View Dependent Claims (20, 21, 22, 23, 24, 25, 26)
-
Specification