CN110646323A - Device and method for measuring liquid density by using equal-volume static buoyancy comparison method - Google Patents

Abstract

The invention relates to a device and method for measuring liquid density by an equal volume static buoyancy comparison method. The device comprises a constant temperature box (1), and a buoyancy rod (5), a buoyancy ball (6), a buoyancy rod (5), a buoyancy ball (6), The detachable fixture (4), the balance (2), the adjustable lifting platform (3) and the sample cup (9), the bottom of the buoyancy rod (5) is connected to the buoyancy ball (6), and the top is fixed on the detachable fixture ( 4), the detachable clamp (4) is placed on the balance (2), and the sample cup (9) is placed on the adjustable lift stand (3), and is located below the buoyancy ball (6) . Compared with the prior art, the present invention has the advantages of high accuracy, unaffected by changes in air pressure and air buoyancy, wide measurement range, high speed, and the like.

Description

Device and method for measuring liquid density by equal volume static buoyancy comparison method

technical field

The invention relates to a device for measuring liquid density, in particular to a device for measuring liquid density by an equal volume static buoyancy comparison method.

Background technique

Density and surface tension are the main physical parameters and important characteristics of liquids. Different substances have different densities, which can preliminarily determine the type of substances and are also important indicators for evaluating the quality of liquids.

At present, the method of quickly testing the density is the densitometer method, which is mainly based on Archimedes' law and the principle of the equilibrium of objects floating on the liquid surface. It is a conventional instrument for measuring the density of liquids. It is composed of a closed glass tube with a uniform thickness at one end and a swollen bubble at the other end. There are two commonly used hydrometers, one is used to measure the density of liquids with a density greater than water, called "heavy meter"; the other is used to measure the density of liquids with a density less than water, called "light meter".

Recently, the development of new nano-scale materials using the characteristics of surface tension has become a hotspot of scientific research. Therefore, it is of great practical significance to study the rapid testing methods and testing instruments of liquid density and surface tension.

Immersion densitometers can only approximate the density and have a small measurement range, no guarantee of accuracy, and no signal output.

With the development of analysis technology and the improvement of testing speed requirements, high-level single-parameter testing instruments have long been sold, but a multi-functional fast tester that can test both liquid density and surface tension has not yet been seen. record.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a fast and accurate device and method for measuring the density of liquid by the equal volume static buoyancy comparison method in order to overcome the above-mentioned defects of the prior art.

The object of the present invention can be achieved by the following technical solutions: a device for measuring liquid density by an isometric static buoyancy comparison method, characterized in that the device comprises an incubator, and buoyancy rods, buoyancy balls, and buoyancy rods placed in the incubator. Remove the fixture, the balance, the adjustable lifting platform and the sample cup, the bottom of the buoyancy rod is connected to the buoyancy ball, the top is fixed on the detachable fixture, the detachable fixture is placed on the balance, and the sample cup is placed on the On a fine-adjustable lift table and below the buoyancy ball.

The diameter of the buoyancy rod is less than 1mm. In order to reduce the error caused by wetting or non-wetting phenomenon.

The sample cup is moved up and down by the adjustable lifting stand, so that the buoyancy ball is immersed in the liquid in the sample cup.

The buoyancy rod or buoyancy ball is provided with a sight mark, the laser is arranged on one side of the detachable fixture, and the beam emitted by the laser is fixed to touch the sight mark, so as to determine the buoyancy ball immersed in the sample cup. Liquid level. Laser beam sighting is used to keep the liquid level consistent with the scale for each measurement.

The detachable clamp includes a frame and a nut set on the top of the frame, the upper part of the buoyancy rod is provided with a thread corresponding to the nut, and the top of the buoyancy rod is screwed into the nut to be fixed.

The micro-adjustable lifting platform includes a fixed rod and a moving rod, one end of the moving rod is fixed on the fixed rod through a moving block, and the other end is provided with a cup holder for fixing the sample cup. A finely adjustable lift table ensures a constant volume of spheres immersed in liquid for each measurement.

The material of the buoyancy ball is glass.

The buoyancy ball can be replaced with a platinum plate or a platinum ring to measure the surface tension of the liquid. When measuring the surface tension of the liquid, the buoyancy ball can be replaced with a platinum ring or a platinum plate to determine the maximum force value of the liquid or the balance value of the liquid surface tension according to the focus of the measurement parameters.

The key to this technology is to ensure that the volume of the sphere immersed in the liquid is constant for each measurement in a constant temperature environment. According to Archimedes' law, an object is subjected to upward buoyancy in a liquid, and the magnitude of the buoyancy is related to the volume of the liquid displaced, that is, F=ρ×V×g. This formula can also be deduced as F=m×g. So buoyancy is also related to the mass of the liquid displaced.

The method for measuring liquid density by using the described device to carry out isometric static buoyancy comparison method is characterized in that, comprises the following steps:

1. Before the test operation, keep the constant temperature of the incubator, place the detachable fixture on the balance in the incubator, fix the buoyancy ball with the detachable fixture, record the reading of the balance or reset the balance to zero;

2. During the test, firstly put the liquid with known density in the sample cup, put the sample cup on the adjustable elevating bench, after constant temperature, make the adjustable elevating bench rise until the laser beam touches the aiming mark, Read out the reading m _of the balance;

3. Place the liquid to be tested in the sample cup, repeat the steps, and read out the reading m of _the balance; the density of the liquid to be tested can _be calculated by _the formula _ρu = ρ x (m _/ m).

Based on the Archimedes principle, the invention uses the comparison of buoyancy to measure the density of the liquid. The specific density bottle method is simple and fast to operate, and at the same time, it also solves the limitation of the immersion type density meter device for measuring the density of the liquid, and has good practicality. The device can also be equipped with platinum plate or platinum ring to measure the surface tension of liquid.

Compared with the prior art, the present invention has the following beneficial effects:

1. Higher accuracy than immersion density meter.

2. Not affected by changes in air pressure and air buoyancy.

3. It can be measured with relatively volatile or viscous liquids.

4. The operation is simple and the device is easy to clean.

5. Wide measurement range and fast speed.

6. It can also measure the surface tension of the liquid.

Description of drawings

Figure 1 is a schematic diagram of the device structure:

Incubator 1; Balance 2; Adjustable lifting platform 3; Detachable clamp 4; Thin rod 5; Buoyancy ball 6; Sight mark 7; Laser 8; Sample cup 9.

FIG. 2 is an enlarged schematic view of the buoyancy ball 6 and the aiming mark 7 .

FIG. 3 is a schematic diagram of wetting or non-wetting phenomenon.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

Example 1

A device for measuring the density of liquid by an isometric static buoyancy comparison method, the device comprises an incubator 1, and a buoyancy rod 5, a buoyancy ball 6, a detachable fixture 4, a balance 2, and a fine-tuning lifting platform placed in the incubator 1 3. The laser 8 and the sample cup 9, the bottom of the buoyancy rod 5 is connected to the buoyancy ball 6, the top is fixed on the detachable fixture 4, the detachable fixture 4 is placed on the balance 2, and the sample cup 9 is placed On the fine-adjustable lifting stage 3 and below the buoyancy ball 6 , the sample cup 9 is moved up and down by the fine-tuning lifting stage 3 , so that the buoyancy ball 6 is immersed in the liquid in the sample cup 9 .

Wherein, the diameter of the buoyancy rod 5 is less than 1mm. The buoyancy rod 5 or the buoyancy ball 6 is provided with a sight mark 7, and the laser 8 is arranged on the side of the detachable fixture 4, and the beam emitted by the laser 8 is passed through. Fixed touching the sighting mark 7 to determine the liquid level at which the buoyancy ball 6 is immersed in the sample cup 9 .

The detachable clamp 4 includes a frame 41 and a nut 42 provided on the top of the frame. The upper part of the buoyancy rod 5 is provided with threads corresponding to the nut, and the top of the buoyancy rod 5 is screwed into the nut to be fixed.

The adjustable lift table 3 includes a fixed rod 31 and a moving rod 32 , one end of the moving rod 32 is fixed on the fixed rod 31 by a moving block 33 , and the other end is provided with a cup holder for fixing the sample cup 9 .

The material of the buoyancy ball 6 is glass material.

The method for measuring liquid density by using the described device to carry out isometric static buoyancy comparison method is characterized in that, comprises the following steps:

(1) Before the test operation, keep the constant temperature of the incubator 1, place the detachable fixture 4 on the balance 2 in the incubator 1, fix the buoyancy ball 6 with the detachable fixture 4, record the reading of the balance 2 or reset the balance 2 to zero ;

(2) During the test, first fill the sample cup 9 with a liquid with a known density, place the sample cup 9 on the adjustable elevating platform 3, and make the adjustable elevating platform 3 rise to the laser 8 after constant temperature When the light beam touches the aiming mark 7, read the reading m _of the balance 2;

(3) Place the liquid to be tested in the sample cup 9, repeat step 2, and read out the reading m of _the balance 2; through _the formula ρ = ρ x (m _/ m), _the value _of the liquid to be tested can be calculated. density.

The above-mentioned buoyancy ball 6 can also be replaced with a platinum plate or a platinum ring to measure the surface tension of the liquid.

Claims (9)

1. The utility model provides a device of isovolumetric static buoyancy method survey liquid density which characterized in that, the device include thermostated container (1) to and arrange buoyancy pole (5), buoyancy ball (6), detachable anchor clamps (4), balance (2), finely tune lift rack (3) and sample cup (9) in thermostated container (1) in, buoyancy pole (5) bottom connect buoyancy ball (6), the top is fixed on detachable anchor clamps (4), detachable anchor clamps (4) place on balance (2), sample cup (9) put on finely tune lift rack (3) to be located buoyancy ball (6) below.

2. The apparatus for determining the density of a liquid by isovolumetric buoyancy comparison according to claim 1, wherein the buoyancy rod (5) has a diameter of less than 1 mm.

3. The device for measuring the density of the liquid by the isovolumetric static buoyancy comparison method according to claim 1, wherein the sample cup (9) is driven to move up and down by the finely adjustable lifting rack (3), so that the buoyancy ball (6) is immersed in the liquid in the sample cup (9).

4. An isometric hydrostatic buoyancy comparison liquid density measuring device according to claim 3, wherein the buoyancy rod (5) or the buoyancy ball (6) is provided with a reference mark (7), the laser (8) is arranged on one side of the detachable clamp (4), and the reference mark (7) is fixedly touched by a light beam emitted by the laser (8), so that the liquid level of the buoyancy ball (6) immersed in the sample cup (9) is determined.

5. The device for measuring the density of the liquid by the isovolumetric static buoyancy comparison method according to claim 1, wherein the detachable clamp (4) comprises a frame (41) and a nut (42) arranged at the top of the frame, the upper part of the buoyancy rod (5) is provided with a thread corresponding to the nut, and the top of the buoyancy rod (5) is screwed into the nut for fixing.

6. The device for measuring the density of the liquid by the isovolumetric static buoyancy comparison method as claimed in claim 1, wherein the finely adjustable lifting platform (3) comprises a fixed rod (31) and a movable rod (32), one end of the movable rod (32) is fixed on the fixed rod (31) through a movable block (33), and the other end of the movable rod is provided with a cup holder for fixing the sample cup (9).

7. The device for measuring the density of the liquid by the isovolumetric buoyancy comparison method according to claim 1, wherein the buoyancy ball (6) is made of glass.

8. The apparatus for measuring the density of liquid by an isometric buoyancy comparison method according to claim 1, wherein the buoyancy ball (6) can be replaced by a platinum plate or a platinum ring to measure the surface tension of the liquid.

9. A method for determining the density of a liquid by an isometric buoyancy comparison method using the device of claim 1, comprising the steps of:

(1) before test operation, keeping the constant temperature of the constant temperature box (1), placing the detachable clamp (4) on the balance (2) in the constant temperature box (1), fixing the buoyancy ball (6) by the detachable clamp (4), and recording the reading of the balance (2) or returning the balance (2) to zero;

(2) when in test, firstly, the sample cup (9) is filled with liquid with known density, and the sample cup (9) is placed inThe finely adjustable lifting rack (3) is lifted to the position where the light beam of the laser (8) touches the reference mark (7) after the temperature is constant, and the reading m of the balance (2) is read_{Has already been used for}；

(3) Placing the liquid to be measured in a sample cup (9), repeating the step (2), and reading the reading m of the balance (2)_{Is prepared from}(ii) a By the formula rho_{Is prepared from}＝ρ_{Has already been used for}×(m_{Is prepared from}/m_{Has already been used for}) The density of the liquid to be measured can be calculated.

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