Portable direct insertion type liquid tuning fork densimeter

Abstract

The utility model discloses a portable in-line liquid tuning fork densimeter which comprises a fork body and a fork tube which are connected in a split mode, a fork arm extending into the fork tube is connected to the fork body, a tuning fork is arranged at the free end of the fork arm, a groove is formed in the side wall of the fork body, a blank cap is connected into the groove in a split mode, and the blank cap is connected with a liquid inlet pipe. A pair of piezoelectric ceramics is pressed and fixed between the blank cap and the groove, and each piezoelectric ceramic is connected with a signal line. The size of the densimeter is reduced to be the size of a test tube, so that the densimeter is convenient to carry and can be used for sampling and testing anytime and anywhere, and the test precision of sample liquid of a small sample experiment is pertinently improved. More importantly, the piezoelectric ceramic is mechanically fixed by means of tight fit connection of the blank cap and the groove, so that not only is the mounting stability of the piezoelectric ceramic improved, but also the problem of measurement distortion of the piezoelectric ceramic caused by an adhesive or a soldering tin body is solved, and the test precision is improved again.

Description

Technical Field

[0001] This utility model relates to the field of densitometer technology, and more specifically to a portable direct-insertion liquid tuning fork densitometer. Background Technology

[0002] A tuning fork density meter is designed based on the vibration principle of components. A piezoelectric ceramic fixed to the tuning fork vibrates when excited by a source signal. The frequency of the vibration is detected by another piezoelectric ceramic. Through amplification, shaping, filtering, and frequency division circuits, the resonance of the tuning fork is stabilized at its inherent resonant frequency. When liquid flows through the tuning fork, the resonant frequency of the tuning fork changes due to the mass and viscosity of the liquid. This frequency change is directly proportional to the density of the liquid. By measuring the vibration frequency between the tuning forks, the density of the liquid can be calculated.

[0003] Existing tuning fork density meters are mainly used for the precise measurement of the density of industrial liquids. However, their installation structure, size, and weight are relatively large, making them unsuitable for measuring the density of experimental samples and small amounts of liquids. This results in large errors in the liquid density test results and insufficient test accuracy.

[0004] Patent ZL202410610335.9 discloses a resonant density meter and a measurement method, including a base, two fixed seats symmetrically arranged on both sides of the upper end of the base, two resonant tubes clamped on the two fixed seats, an excitation piezoelectric ceramic sheet bonded to the upper end of the two resonant tubes, and a vibration pickup piezoelectric ceramic sheet bonded to the lower end of one of the resonant tubes.

[0005] The aforementioned patented piezoelectric ceramics are fixed by adhesive or solder, which are prone to aging and detachment and are subject to resonance, resulting in distortion of liquid density measurement results.

[0006] Patent ZL202420145506.0 discloses a direct-insertion tuning fork density meter, including an instrument, a connecting ring, and a support plate. A protective sleeve is fixedly connected to the bottom end of the connecting ring. A slot allows the protective sleeve to be fixed to the outside of the tuning fork at the bottom of the instrument. The protective sleeve is designed as a filter screen with holes, which can effectively reduce the influence of air bubbles and hanging objects on the instrument, thereby protecting the outside of the tuning fork of the instrument and preventing air bubbles and hanging objects from affecting the measurement data. Utility Model Content

[0007] The purpose of this invention is to overcome the above-mentioned defects of the prior art and provide a portable direct-insertion liquid tuning fork density meter that is easy to carry, can be sampled and tested anytime and anywhere, specifically improves the testing accuracy of small sample liquids, enhances the installation stability of piezoelectric ceramics, and eliminates measurement distortion problems.

[0008] To achieve the above objectives, this utility model is implemented through the following technical solution: a portable direct-insertion liquid tuning fork density meter, characterized in that it includes a pair of fork bodies and fork tubes that are connected separately, a fork arm that extends into the fork tube is connected to the fork body, a tuning fork is provided on the free end of the fork arm, a groove is opened on the side wall of the fork body, a cap is separately connected to the groove, a pair of piezoelectric ceramics are pressed and fixed between the cap and the groove, and a signal line is connected to each piezoelectric ceramic.

[0009] This invention reduces the size of the densitometer to that of a single test tube, making it easy to carry and allowing for sampling and testing anytime, anywhere, thus significantly improving the testing accuracy of small-sample experimental solutions. More importantly, the piezoelectric ceramic is mechanically fixed using a tight fit between the cap and the groove, replacing the chemical fixing methods of adhesives or solder commonly used in the market. This not only improves the installation stability of the piezoelectric ceramic but also eliminates the measurement distortion caused by adhesives or solder, further enhancing testing accuracy.

[0010] Preferably, a pair of centrally symmetrical mounting slots are provided on the inner bottom surface of the groove, and the two piezoelectric ceramics are embedded in the two mounting slots one by one. Each mounting slot has a wire hole connected to it on its side wall, and the outer end of each wire hole reaches the outer wall of the fork. The two signal lines are inserted into the two wire holes one by one, and each signal line is welded to the piezoelectric ceramic in its corresponding side mounting slot.

[0011] A signal wire soldered to the piezoelectric ceramic is placed in the wire hole. One signal wire is connected to the excitation signal source, and the other is connected to the signal processing circuit, which facilitates signal transmission and testing.

[0012] Preferably, the connection between the cap and the groove is a threaded connection.

[0013] Tightening the cap allows for effective clamping and fixing of the piezoelectric ceramic, while the threaded connection makes it easy to open, enabling maintenance and inspection of the solder joints of the internal piezoelectric ceramic and signal lines.

[0014] Preferably, each piezoelectric ceramic piece is covered with a gasket.

[0015] The gasket can provide gentle pressure and force balance to the piezoelectric ceramic during the tightening and pressing process of the cap, effectively protecting the piezoelectric ceramic.

[0016] Preferably, a sealing ring is provided at the connection between the fork body and the fork tube.

[0017] After the test solution is poured into the fork tube, the sealing ring ensures an airtight connection between the fork body and the fork tube to prevent leakage of the test solution.

[0018] Preferably, the connection between the fork body and the fork tube is a threaded connection.

[0019] The fork body and fork tube are connected by a threaded connection. During the tightening process, the sealing ring can be effectively compressed and tightened. This is the most reliable connection method for use with the sealing ring, which takes into account both connection and airtightness.

[0020] Preferably, the fork tube has a built-in filter tube that separates the tuning fork and fork arm from the inner wall of the fork tube, that is, the tuning fork and fork arm extend into the filter tube.

[0021] In use, if the purity of the test sample solution is not high, insoluble substances suspended in the liquid may remain on the surface of the tuning fork after insertion, causing measurement errors. This invention adds a filter tube with filter holes to filter the test sample solution. Insoluble suspended matter in the test sample solution is filtered to the outside of the filter tube, preventing it from adhering to the tuning fork and fork arms, thus eliminating such test errors.

[0022] Preferably, the filter tube has an outwardly folded flange at its opening, and the fork tube has an inwardly folded flange at its opening. The filter tube can be detached and rested on the inwardly folded flange of the fork tube via the outwardly folded flange.

[0023] The filter tube of this utility model is installed in the fork tube in a way that allows for flexible separation. The inner and outer flanges provide support, making it easy to clean and replace the filter tube.

[0024] Beneficial effects: (1) This utility model reduces the size of the densitometer to the size of a test tube, making it easy to carry and allowing for sampling and testing anytime and anywhere, thereby improving the testing accuracy of small sample liquids.

[0025] (2) The piezoelectric ceramic of this utility model is mechanically fixed by the tight fit of the end cap and the groove, which replaces the chemical fixation of most piezoelectric ceramics on the market by adhesive or solder. This not only improves the installation stability of the piezoelectric ceramic, but also eliminates the measurement distortion caused by adhesive or solder to the piezoelectric ceramic, thus further improving the test accuracy.

[0026] (3) This utility model adds a filter tube with filter holes to filter the test sample liquid. Insoluble suspended matter in the test sample liquid is filtered to the outside of the filter tube, avoiding the adhesion of insoluble suspended matter to the tuning fork and fork arm, thereby eliminating the test error of this type of test. In addition, the filter tube is installed in the fork tube in a flexible way, which facilitates the cleaning and replacement of the filter tube. Attached Figure Description

[0027] Figure 1 It is a structural diagram of the utility model;

[0028] Figure 2 This is a schematic diagram of the structure of the fork body of this utility model.

[0029] In the diagram: 1-Fork body, 2-Fork tube, 3-Fork arm, 4-Tuning fork, 5-Groove, 6-Blind cap, 7-Piezoelectric ceramic, 8-Gasket, 9-Mounting groove, 10-Wire hole, 11-Signal line, 12-Filter tube, 13-Outer flange, 14-Inner flange, 15-Sealing ring. Detailed Implementation

[0030] To make the technical means, creative features and objectives of this utility model easier to understand, the following describes this utility model in conjunction with specific embodiments.

[0031] Example 1: Figure 1 and Figure 2 As shown, a portable direct-insertion liquid tuning fork density meter includes a pair of fork bodies 1 and fork tubes 2 that are connected separately. A fork arm 3 that extends into the fork tube is connected to the fork body 1. A tuning fork 4 is provided on the free end of the fork arm 3. A groove 5 is opened on the side wall of the fork body 1. A cap 6 is connected separately in the groove 5. The cap 6 and the groove 5 are connected by a threaded connection.

[0032] A pair of centrally symmetrical mounting slots 9 are provided on the inner bottom surface of the groove 5. A piezoelectric ceramic 7 is embedded in each of the two mounting slots 9. The piezoelectric ceramic 7 is fixed by the screw between the end cap 6 and the groove 5. A wire hole 10 is provided on the side wall of each mounting slot 9 and is connected to it. The outer end of each wire hole 10 reaches the outer wall of the fork body 1. A signal wire 11 is inserted into each wire hole. Each signal wire 11 is welded to the piezoelectric ceramic 7 in the corresponding mounting slot.

[0033] Example 2: Each piezoelectric ceramic 7 is covered with a gasket 8.

[0034] The rest is the same as in Example 1.

[0035] Example 3: The fork body 1 and the fork tube 2 are connected by a threaded connection. A sealing ring 15 is provided at the connection between the fork body 1 and the fork tube 2.

[0036] The rest is the same as in Example 1.

[0037] Example 4: A filter tube 12 is built into the fork tube 2. The filter tube 12 separates the tuning fork 4 and the fork arm 3 from the inner wall of the fork tube 2, that is, the tuning fork 4 and the fork arm 3 extend into the filter tube 12.

[0038] The filter tube 12 has an outwardly folded flange 13 at its opening, and the fork tube 2 has an inwardly folded flange 14 at its opening. The filter tube 12 can be separated and placed on the inwardly folded flange 14 of the fork tube 2 through the outwardly folded flange 13.

[0039] The rest is the same as in Example 1.

[0040] Usage: When measuring the density of the liquid to be tested, first remove the filter tube from the inner ring of the fork tube, pour in the liquid to be tested, ensuring that the tuning fork is submerged. Then, vertically insert the filter tube into the cavity of the fork tube from the inner ring. This will filter insoluble suspended matter in the liquid to the outside of the filter tube, preventing insoluble suspended matter from adhering to the tuning fork and fork arm. Then, tighten the fork body and fork tube with the threaded connection, and use the sealing ring to ensure an airtight seal. Connect one signal line to the excitation signal source and the other to the signal processing circuit to realize the density measurement of the liquid.

Claims

1. A portable direct-insertion liquid tuning fork density meter, characterized in that, It includes a pair of fork bodies and fork tubes that are connected separately. A fork arm is connected to the fork body, and a tuning fork is provided on the free end of the fork arm. A groove is opened on the side wall of the fork body, and a cover is connected separately in the groove. A pair of piezoelectric ceramics are pressed and fixed between the cover and the groove. A signal line is connected to each piezoelectric ceramic.

2. The portable direct-insertion liquid tuning fork density meter according to claim 1, characterized in that, A pair of centrally symmetrical mounting slots are provided on the inner bottom surface of the groove. The two piezoelectric ceramics are embedded in the two mounting slots one by one. Each mounting slot has a wire hole connected to it on its side wall. The outer end of each wire hole reaches the outer wall of the fork. The two signal lines are inserted into the two wire holes one by one. Each signal line is welded to the piezoelectric ceramic in its corresponding side mounting slot.

3. The portable direct-insertion liquid tuning fork density meter according to claim 1 or 2, characterized in that, The connection between the cover and the groove is a threaded connection.

4. The portable direct-insertion liquid tuning fork density meter according to claim 3, characterized in that, Each piezoelectric ceramic piece is covered with a gasket.

5. The portable direct-insertion liquid tuning fork density meter according to claim 1, characterized in that, A sealing ring is provided at the connection between the fork body and the fork tube.

6. The portable direct-insertion liquid tuning fork density meter according to claim 1 or 5, characterized in that, The fork body and the fork tube are connected by a threaded connection.

7. The portable direct-insertion liquid tuning fork density meter according to claim 1, characterized in that, The fork tube contains a filter tube that separates the tuning fork and fork arm from the inner wall of the fork tube, meaning that the tuning fork and fork arm extend into the filter tube.

8. The portable direct-insertion liquid tuning fork density meter according to claim 7, characterized in that, The filter tube has an outwardly folded flange at its opening, and the fork tube has an inwardly folded flange at its opening. The filter tube can be detached and rested on the inwardly folded flange of the fork tube through the outwardly folded flange.

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