Liquid dropping device for contact angle measuring instrument

Abstract

The utility model discloses a liquid dropping device for a contact angle measuring instrument, which belongs to the technical field of interfacial tension testing and comprises a light source system, a light source system support, a bottom plate, a liquid dropping device, an XYZ mobile mechanical control structure, a mechanical control imaging system, a mounting support and an XYZ multi-dimensional adjusting mechanical sample table. The liquid drop device comprises a jet method non-contact liquid dropping system and a liquid drop transfer method contact liquid dropping system, and the jet method non-contact liquid dropping system comprises an ejector pin fixing seat, an injector ejector pin, a driving sliding table, a main injector, a double-conjoined injector fixing seat and a needle head, is an auxiliary device and is used for judging the cleanliness of the surface of a solid sample. According to the liquid drop device for the contact angle measuring instrument, the injection system with two liquid inlet modes is provided, so that the problem that the measured value of a contact angle is influenced by the cleanliness of liquid and solid samples of the inlet liquid can be effectively solved, and meanwhile, the problem that the measured value of the contact angle is easily influenced by the lagging of the contact angle is also solved.

Description

Technical Field

[0001] The utility model relates to the technical field of interfacial tension testing, in particular to a liquid dropping device for a contact angle measuring instrument. Background Art

[0002] At present, the liquid dropping system of a contact angle measuring instrument adopts a micro-injector syringe pump driven by a motor or a manually driven slide table as the driving force or a peristaltic pump. As is well known, the measured contact angle results are easily affected by (1) whether the dropped liquid is clean, especially whether distilled water or pure water is clean, (2) whether the sample surface is clean, and (3) whether there is contact angle hysteresis due to surface roughness or surface structure on the sample surface, etc. There is a squeezing process in the existing liquid dropping system during the process of the liquid droplet reaching the solid sample. When there is surface roughness or surface structure on the solid sample surface, the free energy of the solid surface cannot effectively stretch the liquid droplet, resulting in a significant increase in the contact angle value. This phenomenon is the contact angle hysteresis phenomenon.

[0003] However, the prior art cannot solve the influence of the cleanliness of the liquid and the sample, nor can it solve the influence of contact angle hysteresis.

[0004] Based on this, the utility model designs a liquid dropping device for a contact angle measuring instrument to solve the above problems. Summary of the Invention

[0005] The purpose of the utility model is to provide a liquid dropping device for a contact angle measuring instrument to solve the above technical problems.

[0006] To achieve the above purpose, the utility model provides the following technical solution: A liquid dropping device for a contact angle measuring instrument, comprising: a light source system, a light source system support, a bottom plate, a liquid dropping device, an XYZ moving mechanical control structure, a mechanical control imaging system, a mounting bracket, and an XYZ multi-dimensional adjustment mechanical sample stage;

[0007] The liquid dropping device includes a non-contact liquid dropping system by the spraying method and a contact liquid dropping system by the liquid droplet transfer method. The non-contact liquid dropping system by the spraying method includes: a thimble fixing seat, a syringe thimble, a driving slide table, a main syringe, a double-connected syringe fixing seat, and a needle, which is an auxiliary device for judging the cleanliness of the solid sample surface;

[0008] The contact liquid dropping system by the liquid droplet transfer method includes: a booster air pump, an exhaust valve, a main three-way pipe, a sub-three-way pipe, a power supply, a solid state relay, a straight-through valve, an electronic digital display pressure switch, a spraying valve control board, a pneumatic quick joint, a pressure sealing conversion head for a syringe, a sealing ring, a sub-syringe, a spraying valve, and a spraying needle, which is the main device to form a stationary liquid droplet shape for contact angle measurement on the solid surface and realize the contact angle measurement value.

[0009] Preferably, the double - syringe fixing seat is fixed to the stationary part of the driving slide, the thimble fixing seat is fixed to the moving part of the driving slide, a syringe thimble is arranged inside the main syringe, and a needle is fixed to the injection end of the main syringe.

[0010] Preferably, the main syringe is fixed to the outer wall of the double - syringe fixing seat, and one end of the syringe thimble is fixed to the outer wall of the thimble fixing seat.

[0011] Preferably, one end of the sub - syringe is fixedly connected to the injection valve, the control end of the injection valve is electrically connected to an injection valve control board, the injection needle is fixed to one end of the injection valve, the other end of the sub - syringe is fixedly connected to a pressure - sealing conversion head for syringe, and a sealing ring is arranged at the connection part.

[0012] Preferably, one end of the pressure - sealing conversion head for syringe is threadedly connected to a pneumatic quick - connector, one end of the sub - three - way is connected to a booster air pump through a trachea, and one end is connected to an electronic digital display pressure switch through a trachea, and the third port of the sub - three - way is connected to a main three - way through a trachea.

[0013] Preferably, the other two ports of the main three - way are respectively connected to an exhaust valve and a straight - through valve through tracheas, and the straight - through valve is fixedly connected to one end of the pneumatic quick - connector through a trachea.

[0014] Preferably, the power supply is connected to the booster air pump, the solid - state relay and the electronic digital display pressure switch respectively through electric wires, and the solid - state relay is connected to the booster air pump and the electronic digital display pressure switch respectively through electric wires.

[0015] Preferably, the light source system bracket, the XYZ multi - dimensional adjustment mechanical sample stage and the mounting bracket are all fixed to the top of the bottom plate.

[0016] Preferably, the light source system is fixed to one end of the light source system bracket, the XYZ moving mechanical control structure and the mechanical control imaging system are both fixed to the outer wall of the mounting bracket, and the droplet device is arranged at the control end of the XYZ moving mechanical control structure.

[0017] Compared with the prior art, the beneficial effects of the present utility model are as follows: the droplet device for a contact angle measuring instrument provided by the present utility model realizes the measurement of the cleanliness of the solid sample surface through a contact liquid - inlet mode by providing an injection system with two liquid - inlet modes, uses a non - contact liquid - inlet mode to precisely control the air pressure and control the exhaust to realize the measurement of the cleanliness of the liquid dropped during the test and the formation of a contact angle stop - drop, thereby effectively solving the problem that the cleanliness of the liquid and the solid sample during liquid inlet affects the contact angle measurement value and also solving the problem that the contact angle measurement value is easily affected by contact angle hysteresis.

[0018] The test device for the oil-water-solid three-phase system provided by the control rotary droplet method for measuring the solid-liquid adhesion force includes an overall rotation mechanism to control the inclination of oil and water and read the inclination angle value for calculating the magnitude of the adhesion force. Through the change of the above technical route, it can effectively characterize the interfacial tension measurement of the oil-water-solid three-phase system in the actual production of oilfield chemistry, with high measurement accuracy and good repeatability, thus providing a guarantee for improving oil recovery and drilling quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can obtain other drawings without creative efforts based on these drawings.

[0020] Figure 1 It is a schematic structural diagram of the contact angle measuring instrument for this embodiment;

[0021] Figure 2 It is a schematic diagram of the droplet device for highlighting the contact angle measuring instrument for this embodiment;

[0022] Figure 3 It is a schematic structural diagram of the non-contact droplet system by the spraying method in the liquid-liquid device for the contact angle measuring instrument of this embodiment.

[0023] In the drawings, the list of components represented by each reference numeral is as follows:

[0024] 1. Light source system; 2. Light source system support; 3. Base plate; 4. Droplet device; 5. XYZ moving mechanical control structure; 6. Mechanical control imaging system; 7. Installation support; 8. XYZ multi-dimensional adjustment mechanical sample stage; 41. Non-contact droplet system by the spraying method; 43. Contact droplet system by the droplet transfer method; 431. Thimble fixing seat; 432. Syringe thimble; 433. Driving slide; 434. Main syringe; 435. Double-connected syringe fixing seat; 436. Needle; 411. Booster air pump; 412. Exhaust valve; 413. Main three-way joint; 414. Sub three-way joint; 415. Power supply; 416. Solid state relay; 417. Straight-through valve; 418. Electronic digital display pressure switch; 419. Spraying valve control board; 420. Pneumatic quick joint; 421. Pressure seal conversion head for syringe; 422. Sealing ring; 423. Sub syringe; 424. Spraying valve; 425. Spraying needle. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0026] Please refer to Figures 1-3 , the present utility model provides a technical solution: a liquid dropping device for a contact angle measuring instrument, including: a light source system 1, a light source system bracket 2, a bottom plate 3, a liquid dropping device 4, an XYZ moving mechanical control structure 5, a mechanical control imaging system 6, a mounting bracket 7, and an XYZ multi-dimensional adjustment mechanical sample stage 8;

[0027] The liquid dropping device 4 includes a non-contact liquid dropping system 41 by injection method and a contact liquid dropping system 43 by liquid droplet transfer method. The non-contact liquid dropping system 41 by injection method includes: a thimble fixing seat 431, a syringe thimble 432, a driving slide 433, a main syringe 434, a double syringe fixing seat 435, and a needle 436, which is an auxiliary device for judging the cleanliness of the surface of a solid sample;

[0028] The contact liquid dropping system 43 by liquid droplet transfer method includes: a booster air pump 411, an exhaust valve 412, a main three-way 413, a sub three-way 414, a power supply 415, a solid state relay 416, a straight-through valve 417, an electronic digital display pressure switch 418, a jet valve control board 419, a pneumatic quick connector 420, a pressure sealing conversion head for syringe 421, a sealing ring 422, a sub syringe 423, a jet valve 424, and a jet needle 425, which is the main device to form a stationary liquid droplet shape for contact angle measurement on the solid surface and realize the contact angle measurement value;

[0029] After inserting the needle 436 into a small cup filled with liquid, the moving part of the driving slide 433 can be slid by motor drive or manual control, and liquid can be sucked into and extruded from the main syringe 434.

[0030] Preferably, the double syringe fixing seat 435 is fixed to the stationary part of the driving slide 433, the thimble fixing seat 431 is fixed to the moving part of the driving slide 433, a syringe thimble 432 is arranged in the main syringe 434, and a needle 436 is fixed to the injection end of the main syringe 434;

[0031] The double syringe fixing seat 435 and the stationary part of the driving slide 433 are fixed by screws and remain stationary during operation, while the thimble can be fixed to the moving part of the driving slide 433 by screws and move synchronously.

[0032] Preferably, the main syringe 434 is fixed to the outer wall of the double syringe fixing seat 435, and one end of the syringe thimble 432 is fixed to the outer wall of the thimble fixing seat 431;

[0033] The main syringe 434 is fixed to the double syringe fixing seat 435, and one end of the thimble is fixed to the outer wall of the thimble fixing seat 431, which can assist the main syringe 434 in sucking and squeezing liquid.

[0034] Preferably, one end of the auxiliary syringe 423 is fixedly connected to the injection valve 424. The control end of the injection valve 424 is electrically connected to the injection valve control board 419. The injection needle 425 is fixed to one end of the injection valve 424. The other end of the auxiliary syringe 423 is fixedly connected to the syringe pressure-sealing adapter 421, and a sealing ring 422 is provided at the connection;

[0035] The injection port of the auxiliary syringe 423 is controlled by the injection valve 424 for output. The control of the injection valve 424 is manipulated by the injection valve control board 419. The other end of the auxiliary syringe 423 is externally connected to a pneumatic quick connector 420 through the syringe pressure-sealing adapter, smoothly connecting to the control source. The sealing ring 422 is used to increase the sealing performance at the connection between the syringe pressure-sealing adapter and the auxiliary syringe 423.

[0036] Preferably, one end of the syringe pressure-sealing adapter 421 is threadedly connected to the pneumatic quick connector 420. One end of the secondary three-way 414 is connected to a booster air pump 411 through a trachea, and one end is connected to an electronic digital display pressure switch 418 through a trachea. The third port of the secondary three-way 414 is connected to the main three-way 413 through a trachea;

[0037] The main three-way 413 assists in the gas output of the booster air pump 411, and the electronic digital display pressure switch 418 is used to assist in driving the air pump to operate.

[0038] Preferably, the other two ports of the main three-way 413 are respectively connected to an exhaust valve 412 and a straight-through valve 417 through tracheas. The straight-through valve 417 is fixedly connected to one end of the pneumatic quick connector 420 through a trachea;

[0039] The exhaust valve 412 controls the exhaust operation of the main three-way 413, while the straight-through valve 417 is used to control the gas delivery towards the pneumatic quick connector 420.

[0040] Preferably, the power supply 415 is respectively connected to the booster air pump 411, the solid-state relay 416, and the electronic digital display pressure switch 418 through wires. The solid-state relay 416 is respectively connected to the booster air pump 411 and the electronic digital display pressure switch 418 through wires.

[0041] Preferably, the light source system bracket 2, the XYZ multi-dimensional adjustment mechanical sample stage 8, and the mounting bracket 7 are all fixed to the top of the bottom plate 3.

[0042] Preferably, the light source system 1 is fixed to one end of the light source system bracket 2, the XYZ moving mechanical control structure 5 and the mechanical control imaging system 6 are both fixed to the outer wall of the mounting bracket 7, and the droplet device 4 is arranged at the control end of the XYZ moving mechanical control structure 5;

[0043] The light source system 1, the XYZ multi-dimensional adjustment mechanical sample stage 8, the XYZ moving mechanical control structure 5 and the mechanical control imaging system 6 are all original mechanisms of the existing contact angle measuring instrument.

[0044] The specific principle and application of this embodiment are as follows: The method for judging the cleanliness of the surface of a solid sample is: Through the droplet transfer method contact drip system 43, suck the test liquid such as distilled water or pure water into the main syringe 434, then extrude the micro-droplet and suspend it below the needle 436 to form a hanging drop, and calculate the surface tension value of the liquid by the Young-Laplace equation fitting method. If the test value does not meet the standard value, the main syringe 434 and the needle 436 need to be cleaned and the liquid replaced until the test value meets the standard value.

[0045] Then, drop a liquid such as distilled water or pure water on the surface of the tested solid, then suck it back into the main syringe 434, and finally extrude the micro-droplet and suspend it below the needle 436 to form a hanging drop. Calculate the surface tension value of the liquid after cleaning the solid surface by the Young-Laplace equation fitting method. If the test value does not meet the standard value, and if it is lower than the standard value, the solid surface is regarded as unclean.

[0046] The solid sample with an unclean surface needs to be cleaned until the surface tension value obtained with the test liquid meets the standard value.

[0047] The method for judging the cleanliness of the liquid in the droplet device of the contact angle measuring instrument is:

[0048] The first step: Load the test liquid into the secondary syringe 423: Unscrew the syringe pressure seal conversion head 421, pour the test liquid into the secondary syringe 423, and then reinstall the syringe pressure seal conversion head 421.

[0049] The second step: Increase the pressure in the secondary syringe 423 and disconnect the pressure: Close the exhaust valve 412, open the straight-through valve 417, after setting the electronic digital display pressure switch 418 to the target pressure value, then open the exhaust valve 412.

[0050] The third step: Test the cleanliness of the liquid in the droplet device of the contact angle measuring instrument:

[0051] Control the injection valve 424 to open for a set time, such as 2 seconds, through the injection valve control board 419. After a hanging drop is formed on the injection needle 425 by the gravitational force of the test liquid, close the injection valve 424 and then open it. Calculate the surface tension value of the liquid by fitting the Young-Laplace equation. If the test value does not meet the standard value, the syringe and the needle need to be cleaned and the liquid needs to be replaced until the test value meets the standard value.

[0052] The method for forming a sessile drop required for contact angle measurement on the solid surface and solving the influence of the hysteresis contact angle is as follows:

[0053] First step: Fill the auxiliary syringe 423 with the test liquid. Unscrew the pressure-sealing conversion head 421 of the syringe. After filling the auxiliary syringe 423 with the test liquid, reinstall the pressure-sealing conversion head 421 of the syringe.

[0054] Second step: Increase the pressure in the auxiliary syringe 423 and disconnect the pressure. Close the exhaust valve 412, open the valve, and set the electronic digital display pressure switch 418 to the target pressure value.

[0055] Third step: Form a sessile drop required for contact angle measurement on the solid surface and measure the contact angle value:

[0056] Control the injection valve 424 to open for a set time, such as 1 millisecond, through the injection valve control board 419. The test liquid is non-contact injected onto the solid sample due to air pressure to form a sessile drop for measuring the contact angle. Use machine vision recognition technology to find the edge of the liquid drop and fit the corresponding liquid drop curve equation to calculate the contact angle value.

[0057] Through the above non-contact injection, the influence of the contact angle hysteresis, which is easily affected by the surface roughness and surface structure in the contact liquid injection method of the liquid drop transfer method, can be solved.

[0058] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "coaxial", "bottom", "one end", "top", "middle", "the other end", "upper", "one side", "top", "inner", "front", "center", "both ends", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention.

[0059] In the present utility model, unless otherwise clearly defined and limited, terms such as "installation", "setting", "connection", "fixation", "swivel connection" and the like shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements or the interaction relationship between two elements. Unless otherwise clearly defined, for those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0060] Although the embodiments of the present utility model have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present utility model. The scope of the present utility model is defined by the appended claims and their equivalents.

Claims

1. A liquid dropping device for a contact angle measuring instrument, characterized in that: include: Light source system (1), light source system bracket (2), base plate (3), droplet device (4), XYZ mobile mechanical control structure (5), mechanical control imaging system (6), mounting bracket (7), XYZ multi-dimensional adjustment mechanical sample stage (8); The droplet device (4) comprises a non-contact droplet system (41) of the jet method and a contact droplet system (43) of the droplet transfer method. The non-contact droplet system (41) of the jet method comprises: an ejector pin holder (431), a syringe ejector pin (432), a driving slide (433), a main syringe (434), a double-connected syringe holder (435), and a needle (436), and is an auxiliary device for judging the cleanliness of the surface of a solid sample. The droplet transfer method contact dripping system (43) comprises: a booster air pump (411), an exhaust valve (412), a main three-way valve (413), a secondary three-way valve (414), a power supply (415), a solid-state relay (416), a straight-through valve (417), an electronic digital pressure switch (418), an injection valve control panel (419), a pneumatic quick connector (420), a pressure seal conversion head for a syringe (421), a sealing ring (422), a secondary syringe (423), an injection valve (424), and an injection needle (425), which are the main devices for completing the formation of a sessile droplet morphology used for contact angle measurement on a solid surface and realizing contact angle measurement.

2. The liquid dropping device for a contact angle measuring instrument according to claim 1, characterized in that: The double-jointed syringe fixing seat (435) is fixed to a stationary position of the driving slide (433), the ejector fixing seat (431) is fixed to a moving position of the driving slide (433), a syringe ejector (432) is arranged in the main syringe (434), and a needle (436) is fixed to the injection end of the main syringe (434).

3. The liquid dropping device for a contact angle measuring instrument according to claim 2, characterized in that: The main syringe (434) is fixed to the outer wall of the double-jointed syringe fixing seat (435), and one end of the syringe ejector pin (432) is fixed to the outer wall of the ejector pin fixing seat (431).

4. The liquid dropping device for a contact angle measuring instrument according to claim 1, characterized in that: One end of the auxiliary syringe (423) is fixedly connected to the injection valve (424); the control end of the injection valve (424) is electrically connected to the injection valve control board (419); the injection needle (425) is fixed to one end of the injection valve (424); the other end of the auxiliary syringe (423) is fixedly connected to the syringe pressure sealing conversion head (421), and a sealing ring (422) is provided at the connection.

5. The liquid dropping device for a contact angle measuring instrument according to claim 4, characterized in that: One end of the syringe pressure seal conversion head (421) is threadedly connected to a pneumatic quick connector (420), one end of the secondary tee (414) is connected to a booster air pump (411) via an air pipe, and one end is connected to an electronic digital pressure switch (418) via an air pipe, and the third port of the secondary tee (414) is connected to a main tee (413) via an air pipe.

6. The liquid dropping device for a contact angle measuring instrument according to claim 5, characterized in that: The other two ports of the main tee (413) are respectively connected to an exhaust valve (412) and a straight-through valve (417) through air pipes, and the straight-through valve (417) is fixedly connected to one end of a pneumatic quick connector (420) through an air pipe.

7. The liquid dropping device for a contact angle measuring instrument according to claim 5, characterized in that: The power source (415) is connected to the booster air pump (411), the solid-state relay (416), and the electronic digital display pressure switch (418) through wires, and the solid-state relay (416) is connected to the booster air pump (411) and the electronic digital display pressure switch (418) through wires.

8. The liquid dropping device for a contact angle measuring instrument according to claim 1, characterized in that: The light source system bracket (2), the XYZ multi-dimensional adjustment mechanical sample stage (8) and the mounting bracket (7) are all fixed on the top of the base plate (3).

9. The liquid dropping device for a contact angle measuring instrument according to claim 8, characterized in that: The light source system (1) is fixed to one end of a light source system bracket (2), the XYZ movable mechanical control structure (5) and the mechanical control imaging system (6) are both fixed to the outer wall of a mounting bracket (7), and the droplet device (4) is arranged at the control end of the XYZ movable mechanical control structure (5).

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