Summary of the invention
The present invention provides a kind of simple and effective fluid sampling device for solving the shortcomings and deficiencies described in above-mentioned background technology.
For achieving the above object, the technical solution used in the present invention is: a kind of device of liquid sampling, comprise fluid infusion container, two or more liquid container to be measured, sampling line, sampling container, the sampling probe being arranged at corresponding sampling line one end, the peristaltic pump corresponding with corresponding sampling line, described peristaltic pump one end is communicated with liquid container to be measured, and the other end is provided with the liquid outlet of replenishing line and the sampling line other end to be connected be connected with fluid infusion container.
As a further improvement on the present invention, described sampling line is also provided with two-dimensional motion mechanism and feedback pipe pressure to the weigher of peristaltic pump control system.Above-mentioned two-dimensional motion mechanism adopts motor, ball-screw respectively, by controlling to realize moving forward and backward of liquid outlet and moving up and down of tie point to the rotating of motor.Above-mentioned weigher comprises pressure transducer and is located at the liquid container above pressure transducer, weigher records the pressure produced during each pipeline work and feeds back to peristaltic pump control system, by control system, close-loop feedback control is carried out to peristaltic pump sampling value, ensure that the precision of sampling.
As a further improvement on the present invention, a described three-way connection is connected between peristaltic pump, liquid outlet, replenishing line.
As a further improvement on the present invention, described replenishing line is provided with the first retaining valve of the unidirectional inflow peristaltic pump of conducting liquid stream, described liquid outlet front end and sampling line are respectively equipped with second, third retaining valve, the second described retaining valve conducting liquid stream flows to liquid outlet from peristaltic pump, and the 3rd described retaining valve conducting liquid stream flows into sampling line; First, second described retaining valve is arranged on rear side of three-way connection.
As a further improvement on the present invention, a three-way solenoid valve connects liquid outlet and sampling line
Compared with prior art, the invention has the beneficial effects as follows: with peristaltic pump, sampling line is controlled, structure is simple, and reduce and control cost, in addition, by setting up weigher, detection being carried out and FEEDBACK CONTROL peristaltic pump to sampling line, objectively achieving the automatic calibration to sampling line, ensure that sampling precision.
Embodiment
The present invention includes fluid infusion container 8, two or more liquid container 9 to be measured, sampling line, sampling container 7, the sampling probe 1 being arranged at corresponding sampling line one end, the peristaltic pump 2 corresponding with corresponding sampling line, peristaltic pump 2 one end is communicated with liquid container 9 to be measured, liquid outlet 10, one three-way connection that the other end is provided with replenishing line and the sampling line other end to be connected be connected with fluid infusion container 8 is connected between peristaltic pump 2, liquid outlet 10, replenishing line.
Sampling line is also provided with two-dimensional motion mechanism and feedback pipe pressure to the weigher 11 of peristaltic pump 2 control system, and weigher 11 comprises pressure transducer and is located at the liquid container 12 above pressure transducer.
Replenishing line is provided with the first retaining valve 3 of the unidirectional inflow peristaltic pump 2 of conducting liquid stream, liquid outlet 10 front end and sampling line are respectively equipped with second, third retaining valve 4,6, second retaining valve 4 conducting liquid stream flows to liquid outlet 10 from peristaltic pump 2, and the 3rd described retaining valve 6 conducting liquid stream flows into sampling line; First, second retaining valve 3,4 is arranged on rear side of three-way connection.
Fluid sampling device is divided into following several stage work:
First stage: preparatory stage
Sampling probe 1 is in a position, and peristaltic pump 2 operates counterclockwise, draws fluid infusion solvent, makes fluid infusion solvent be full of the pipeline between fluid infusion container and peristaltic pump by the first retaining valve 3, peristaltic pump 2; System starts, the tie point 5 of mobile sampling line or liquid outlet 10, make liquid outlet 10 be connected with tie point 5.Now peristaltic pump 2 operates clockwise, draw the testing liquid of liquid container to be measured 9 li, testing liquid is made to be full of whole pipeline by peristaltic pump 2, second retaining valve 4, tie point 5, the 3rd retaining valve 6, and form loop and finally get back in liquid container to be measured, now sampling system is full of solvent, and in sampling line, air is thoroughly discharged.
Subordinate phase: calibration phase
Before sampling, during as needs automatic calibration, by being located at the liquid container 12 above pressure transducer.Solution to be measured is introduced in sampling line, now weigher is recorded by pressure transducer the pressure produced during each pipeline work and feeds back to peristaltic pump control system, controlled with to peristaltic pump sampling value by control system, ensure that the precision of sampling.
Phase III: sample phase
Before formal sampling, operated counterclockwise by peristaltic pump 2, the pressure produced in discharge conduit flow duct, then mobile link point 5 or liquid outlet 10, makes liquid outlet 10 and tie point 5 disconnect.Consider that liquid outlet 10 is with the separated of tie point 5 and be connected the operational complicacy caused, now, also by setting up a three-way solenoid valve, connecting liquid outlet 10, sampling line and tie point 5, so can carry out direct sample under the condition not disconnecting tie point and liquid outlet.During sampling, the control system of the peristaltic pump 2 configured respectively by every bar sampling line carries out signal control to the running accuracy of peristaltic pump, now peristaltic pump 2 operates clockwise, a bit quantitative liquid to be measured is extracted from liquid container 9 to be measured, by retaining valve 4, testing liquid is incorporated in sampling container 7.
Fourth stage: fluid infusion stage
For ensureing that the total amount of liquid in liquid container 9 to be measured does not reduce, need supplement and the solution of sample flow equivalent in testing container 9, now, peristaltic pump 2 antiport, by retaining valve 3, peristaltic pump 2, takes out the solvent of equivalent in liquid container 9 to be measured from fluid infusion container 8.
Five-stage: return the liquid stage
The position of sampling probe 1 rises to a from b, mobile link point 5 or liquid outlet 10, liquid outlet 10 is connected with tie point 5, solution is introduced in liquid container 9 to be measured by the peristaltic pump 2 of clockwise running, retaining valve 4, tie point 5, retaining valve 6, now, peristaltic pump 2 running makes to be full of air in pipeline, for lower sub-sampling is prepared.