SU823874A1 - Liquid metering device - Google Patents

Description

(54) LIQUID DISPENSER

one

The invention relates to dispensing devices and can be used in microbiology, for example, in laboratory apparatus for cultivating microorganisms, as well as in the medical industry when it is required to maintain sterility of the dispensed liquid.

A device for dispensing a liquid is known, comprising a dispenser, measuring units with a pinch valve between their connection points to the line and a tap.

A disadvantage of the known devices is the impossibility of providing automatic control of the dose value. The closest in technical essence to the proposed one is a liquid metering device containing a membrane metering chamber with inlet and outlet lines and installed controlled valves, and a measuring burette 2. ,

However, in the known device, it is not the pumped liquid itself that is controlled, but the movement of the indicator liquid in the burette, which is indirectly related to the dose value. It is possible that

the metered liquid is not pumped due to leakage or filling with gas, as a result, the indicator incorrectly shows the dose of the pumped liquid.

The purpose of the invention is to improve the accuracy of determining the actual value of 1 dose while maintaining sterility of the dispensed liquid.

The goal is achieved by the fact that the Merna burette is connected at both ends with the output line of the dosing chamber, and

5, an additional control valve is installed between the connection points, the inlet of which is connected to the inlet valve of the dosing chamber via a control signal.

0

The drawing schematically shows the proposed device. General form. .

The dispenser contains a dispensing chamber 1, with a membrane 2, an inlet 3 and an outlet 4 line with installed pinch valves 5, 6 and 7, a measuring burette 8. They are installed at the locations of the valves 5, 6 and 7

0 as an elastic tube. Valves 5, 6 and

7 and the chamber 1 is connected to the source 9 controlled by its action, made in the form of a generator of pneumatic pulses. For use of tubes of different diameters, pinch valves 5, 6 and 7 are equipped with adjustable screws 10.

The device works as follows.

When supplying the control signal to the output valve 6, the tube is clamped on line 4, and the internal cavity of the metering chamber

1 through the open valve 5 is filled with liquid, pressing the membrane 2 against the inner wall of the chamber 1.

In the following cycle, the control signal from source 9 is fed to the inlet valve 5 and simultaneously to valve 7, while valves 5 and 7 clamp the lines 4. At the same time, the control signal from valve 6 is removed and the pressed tube opens. The control signal from the source 9 is then fed to the dosing chamber 1, the membrane

2 moves to another extreme position, as a result of which a dose of fluid is ejected

From the metering chamber 1 to the tube of the measuring burette 8. The filling tube is set to liquid in the upper level; the next moment the control signal & l from source 9 is fed to the outlet valve 6, and the tube is clamped and the control signal from the inlet valve 5 of the pinch valve 7 and the dispensing chamber 1 is removed and a new filling of the dosing chamber 7 takes place through the open valve 5. The liquid from the tube 8 through the open valve 7 is discharged to the consumer, mounted in the tube 8 in the lower position. The difference between the upper and lower levels of the liquid in the tube 8

judge the size of the unit dose of the membrane dosing chamber 1..

In the future, the cycle of operation of the metering device is repeated.

Thus, direct control of the dose is achieved by performing the design of the dispenser with functionally separated valves and the dispensing chamber controlled by external signals, which allows the pinch valve of the metering device to be connected in parallel with the inlet valve of the dispenser, thereby delaying measuring device pumped liquid.

The measurement process is carried out without compromising sterility, since the measuring burette is not in contact with the external environment.

Invention Formula

I

A fluid dispenser containing a membrane metering chamber with inlet and outlet lines and controlled valves installed on them, and a measuring burette, characterized in that, in order to improve the accuracy of determining the effective dose, while maintaining sterility of the dispensed liquid, the burette is connected to both ends with the output line of the metering chamber, - and between the connection points an additional control valve is installed, the input of which is connected via a control signal with the input of the input valve on the dosing chamber.

Sources of information taken into account in the examination

1. USSR author's certificate number 465552, cl. G 01 F 11/00, 1972..

2. USSR author's certificate No. 351084, cl. G 01 F 11/28, 1971.

Claims (1)

Claim I A liquid dispenser containing a membrane metering chamber with inlet and outlet lines and mounted on them by controlled valves, and a measuring burette, characterized in that, in order to improve the accuracy of determining the actual value, dose while maintaining the sterility of the dosed liquid, the measuring burette is connected at both ends with output line through the metering chamber, · between the connection points an additional controlled valve is installed, the input of which is connected by a control signal to the input valve input Looking around the chamber.