RU1774180C - Liquid dosing apparatus - Google Patents

Abstract

The inventive closed measuring tank (3) is placed in the tank (1) and is filled with liquid through the holes

Description

g in 4

The invention relates to dosing devices and can be used in the metallurgical, chemical and other industries with remote control of dosing.

Known dispenser containing a container for liquid, placed in it a siphon and a bellows, the lower part of which is attached to its bottom, and the top to the float, Introduced into it an air tube, a ferromagnetic element with a permanent magnet, one of which is attached to the bottom of the container the cavity of the bellows, and the other to the upper part of the bellows with the possibility of magnetic interaction with each other, moreover, the bellows is sealed and communicates with the atmosphere through an air tube, and the float is made with step section vertically and is attached to a large cross-section to an ilfon (USSR AS No. 1262290, class G 01 F 13/00, 1985).

However, this dispenser has low reliability when working with aggressive fluids due to the fact that the bellows at the bending points is prone to destruction.

The closest to the proposed effect and technical effect is a liquid dispenser containing a reservoir, a measuring tank with a drain pipe and two pipelines. The measured capacity of the dispenser is located in the tank under the level of the liquid to be dosed and is limited by two detachable bodies - upper and lower, the last of which is made in the form of a glass with an opening at the bottom. Inside the measuring tank, a measuring vessel connected to one of the pipelines with a drain pipe is installed, above which a funnel is located, connected through another pipeline to the compressed air line (AS USSR No. 425053, class G 01 F 11/28, 1972).

However, the known dispenser has insufficient accuracy due to the influence of a constantly changing liquid level in the tank, because when a portion of liquid is dispensed, air displaces the liquid from the pipeline not only into the funnel and hole in the glass, but also into the neck of the measuring vessel, and since the height of the liquid column in the pipe will decrease as it flows from the tank, the dose will also change. The accuracy of dosing is also influenced by the possibility of siphoning during water hammer in the tank, as the end of the drain pipe is below the liquid level in the tank. Accuracy will decrease when mechanical particles are present in the liquid due to the absence of a settling zone. In a known dispenser capacity

mounted on the bottom of the tank, and the hole in the vessel is on the side and may become clogged by such particles.

The purpose of the invention is to improve the accuracy of dosing.

The goal is achieved in that the liquid dispenser, which is secured in the supply tank, a closed measuring tank, the upper part of which

equipped with a nozzle for supplying compressed gas, and the lower one is connected to the supply tank through at least one hole and a drain nozzle connected to the measuring tank, an axis is introduced into it, focusing on

one end, and the holes are made in the bottom of the measuring tank and equipped with a locking member with zero buoyancy, the axis of the free end is mounted vertically on the bottom of the measuring tank and on it with the possibility of movement between the bottom and the stop there is a locking body, the area SK of which is selected from the ratio

5k (3-4) 2 So, i 1

SK area of the locking element;

So the area of the i-th hole in the bottom of the measuring tank, and the distance between the bottom of the measuring tank and the stop is selected from the condition:

h- (0.08-0.10) dK

where di is the diameter of the shutoff body, and the outlet end of the drain pipe is located above the tank, and the measured capacity is fixed in the tank above its bottom with

the gap.

The drawing shows a diagram of the proposed fluid dispenser,

The dispenser consists of a tank 1, inside of which a measuring tank housing 3 is fixed on the support brackets 2. The tank 1 is much larger than the measuring tank 3. A drain pipe 6 is installed in the cavity of the measuring tank 3, passing through the top cover of the tank 3, and on the axis

4, a stop 5 is fixed. In the bottom 7 of the body of the measuring tank 3 there are through holes 8. In the tank 3 on the axis 4 with a stop 5 there is a freely moving valve 9 having zero buoyancy.

All openings 8 in the bottom 7 are located on the area immediately below the valve 9, and are associated with the area of the valve 9 by the ratio:

Zk (3-4) Ј

So

i -1

ABOUT)

where SK is the area of the valve 9 overlapping the openings in the bottom 7 of the measuring container 3;

So is the area of the 1st hole in the bottom 7 in the measuring tank 3,

The stroke of the valve 9 is limited by the stop 5 and is selected from the ratio

h (0.08-0.10) dK (2)

where is the UK valve diameter,

Compressed air from the compressed air line 10 is supplied through a shut-off device 11 through a pipe 12 to a measuring tank 3. The shut-off device 11 is controlled by a control unit 13, The fluid squeezed out of the tank 3 into the nozzle b is supplied to the funnel 14, and from it to the receiving capacity 15.

The end of the drain pa. cut-off b is located above the liquid level in the tank 1. The gap between the nozzle 6 and the funnel 14 is necessary for breaking the liquid jet in the nozzle 6 after removing the air pressure. The fluid in the tank 1 enters through the locking device 16 through the pipe 17.

The liquid dispenser works as follows

In the initial state, the tank 1 is filled with liquid through a pipe 17 through an open shut-off device 16 to the level of H1, where H1 is the height of the liquid column from the level 7 of the measuring tank 3 to the surface of the liquid. The valve 9 is selected depending on the physicochemical properties of the liquid so that its weight is equal to the weight of the liquid displaced by it, i.e. the valve had zero buoyancy.

The valve 9 of the measuring container 3 closes all openings 8 in the bottom 7 after it is filled with liquid.

During filling of the measuring tank 3 with liquid, the compressed air line 10 is blocked by a shut-off device 11, for example, a three-way valve or other shut-off device, and the cavity of the measured tank 3 is connected through the pipeline 12 through the shut-off device 11 to the atmosphere. When dispensing, the control unit 13 through the locking device 11 connects the compressed air line 10 with a measuring tank 3.

After supplying air from the overpressure line 10, the liquid is discharged through the nozzle 6 into the funnel 14, which flows down into the tank 15. The valve 9 of the measured tank 3 is pressed against the openings 8 by the hydrostatic force F

F pSK + Рк - Рж (3)

where F is hydrostatic force;

p is the air pressure in the highway;

Зк - valve area;

Pk valve weight 9;

Rj is the weight of the displaced fluid by the valve 9 in suspension.

Rk Rzh

The hydrostatic force F - is a variable value and depends on the specific gravity of the fluid (fluid composition), the height of the fluid column, the weight and area of the valve 9.

The liquid column value Hi acting on valve 9 is a value decreasing to zero. After reaching Hi 0, tank 1 must be filled with the next portion of liquid.

After emptying the measuring tank 3, the air supply is shut off and it is connected to the atmosphere.

Due to the fact that the measuring tank 3 is empty and the air pressure is removed, the hydrostatic force F opens the valve from the bottom 7

F - / EJ J So + Rk (5)

I 1

since pSK 0 and Pg 0.

where RJ is the specific gravity of the liquid;

So is the area of one hole;

p is the number of holes;

RK - oes valve.

The resulting force F, due to the height of the liquid column Hi, tear the valve 9 from the bottom 7 and open the holes 8, the total

whose surface is equal

So for the passage of liquid into the measuring tank 3.

In this case, the valve 9 moves up along the axis 4 to the stop 5 so that the stroke of the valve 9 is selected from the ratio:

h (0, CVO, 1) dK (6)

where di is the diameter of the valve.

When filling the measuring container 3 with liquid, the value of the hydrostatic force F in equation 5 changes;

F / Aug 2 So (Hi-H2) + PK-P w (7)

i 1

where H2 is the height of the liquid column after filling the measuring tank 3;

Pk valve weight;

Rf is the weight of the fluid displaced by the valve in suspension.

The height of the liquid column in the tank 1-Dimensional tank 3 is completely filled and the liquid is installed in the nozzle 6 at the level H. The height of the liquid column Hi decreases by the size of the measured tank 3. Then equation 7 can be written;

F Rk-Rzh (8)

The valve 9 along the axis 4 will lower to the bottom 7 of the measuring tank 3 and will close the holes 8 in the bottom 7,

The Merna tank 3 is filled with liquid and ready for the next cycle.

In violation of the equation

Zk (3-4) 2 So,

I 1

when the size of the openings is larger than the valve, the metering accuracy is impaired due to leakage of fluid under the valve.

When the value of valve 9 to the stop 5 is greater than the calculated value according to equation (3), fluid leakage is possible, and, consequently, a decrease in the metering accuracy of the dispenser.

The use of the inventive liquid dispenser eliminates the simultaneous operation of the supply pipe 17 and the pipe 6, which increases the metering accuracy due to the absence of the influence of water hammer and interruptions in the supply of liquid.

The dose value can be changed by changing the position of the nozzle b in the measuring tank 3, subject to the above requirements for the weight and area of the valve and its free travel. The liquid dispenser is applicable to highly aggressive and toxic liquids containing mechanical particles, due to the absence of moving parts except valve 9, and the settling zone under the tank 3.

Claims (1)

The dispenser is easy to manufacture, the manufacturing formula is a liquid dispenser containing a closed measuring tank fixed in the supply tank, the upper part of which is equipped with a compressed gas supply pipe, and the lower is connected to the supply tank through at least one opening and a drain connected to the measuring tank nozzle, characterized in that, in order to increase the accuracy of dosing, an axis is inserted into it with a stop at one end, and the holes are made in the bottom of the measuring tank and equipped with a locking body with zero buoyancy, the axis with its free end mounted vertically on and on the measuring tank bottom with the ability to move between the bottom and emphasis installed shut-off element, area 5k which is selected from the relation S « (3-4) 2, So, where So is the area i-ro from- i 1 versts in the bottom of the measuring tank, and the distance l between the bottom of the measuring tank and the stop is selected from the condition h (0.08-0.1) dK, where UK is the diameter of the shut-off element, with the outlet end of the drain pipe located above the tank, and The measured capacity is fixed in the tank above its bottom with a gap.