Surface tension tester
By using LCR bridges and conductive capillaries in the surface tension tester, a closed loop is formed and the immersion depth of the conductive capillaries is recorded, the problem of inaccurate capillary depth data in the prior art is solved, and the accuracy of surface tension measurement is improved.
Patent Information
- Application Number
- CN202420275462.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-04
- Publication Date
- 2025-02-11
- Estimated Expiration
- 2034-02-04
AI Technical Summary
During the measurement process of existing surface tension measuring instruments, the depth data of the capillary immersion into the sample to be measured is inaccurate, resulting in errors in the measurement results and affecting the measurement accuracy.
A surface tension tester was designed, using an LCR bridge, a conductive rod and a conductive capillary to form a closed circuit when it comes into contact with the liquid to be tested through the conductive capillary. The zero position is recorded using the LCR bridge, and the movement amount of the conductive capillary is accurately measured. Its immersion depth.
By accurately recording the immersion depth of the conductive capillary, the accuracy of surface tension measurement is improved, error is reduced, and measurement reliability is enhanced.
Smart Images
Figure CN222461262U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field related to surface tension testing equipment, in particular to a surface tension testing instrument. Background Art
[0002] The maximum bubble method is a commonly used method for measuring the surface tension of liquids and is less affected by other factors. The principle is to immerse the capillary in the sample to be tested and blow gas into the capillary. The air pressure in the capillary is detected with a micro differential pressure gauge. When the diameter of the bubble blown out of the capillary is equal to the diameter of the capillary, the pressure in the bubble reaches the maximum value. The surface tension of the sample to be tested can be calculated by the corresponding formula.
[0003] At present, the position where the capillary contacts the liquid surface of the sample to be tested is mostly determined by the operator observing the changes in the readings of the micro differential pressure meter, which has low accuracy. Inaccurate position of the liquid surface of the sample to be tested will lead to inaccurate depth data of the capillary immersion in the sample to be tested, thereby causing errors in the measurement results of the surface tension, affecting the measurement accuracy of the surface tension measuring instrument. Utility Model Content
[0004] Based on this, it is necessary to provide a surface tension measuring instrument with relatively high measurement accuracy to address the problem that the depth data of the capillary immersed in the sample to be measured is inaccurate during use of the current surface tension measuring instrument, resulting in errors in the measurement results.
[0005] The present application provides a surface tension tester, comprising a frame, a measuring cylinder, a lifting structure and a measuring structure, wherein the measuring cylinder and the lifting structure are both arranged on the frame, and the measuring cylinder is used to accommodate a liquid to be tested;
[0006] The measuring structure includes an LCR bridge, a conductive rod, a conductive capillary, an air inlet pipe and a micro differential pressure gauge. The conductive capillary is fixed to the moving end of the lifting structure. The lifting structure can drive the conductive capillary to move up and down to control one end of the conductive capillary to immerse in or leave the liquid to be measured. The other end of the conductive capillary is connected to the air inlet pipe and the micro differential pressure gauge at the same time.
[0007] The end of the conductive rod is immersed in the liquid to be tested, and the conductive rod and the conductive capillary are electrically connected to the LCR bridge respectively, so that when the conductive capillary is immersed in the liquid to be tested, a closed loop is formed between the LCR bridge, the conductive rod, the liquid to be tested and the conductive capillary.
[0008] In one embodiment, the conductive capillary is made of platinum, nickel, molybdenum or tantalum.
[0009] In one embodiment, the conductive rod is made of stainless steel.
[0010] In one of the embodiments, the frame is further provided with a heating furnace, and the measuring cylinder is arranged in the heating furnace.
[0011] In one embodiment, the lifting structure includes a first lifting component and a second lifting component, both of which can drive their own moving ends to move in a vertical direction; the second lifting component is arranged on the frame, the first lifting component is arranged at the moving end of the second lifting component, and the conductive capillary is fixed to the moving end of the first lifting component.
[0012] In one embodiment, the measuring cylinder includes a connecting rod, a lifting basket and a crucible, the center of the connecting rod passes through in the vertical direction, one end of the connecting rod is fixed to the lifting basket, and the other end is fixed to the movable end of the second lifting assembly, and the crucible is detachably arranged on the lifting basket; the conductive capillary passes through the connecting rod.
[0013] In one of the embodiments, a plurality of heat insulation sheets are fixed on the connecting rod at intervals along the vertical direction.
[0014] In one of the embodiments, the crucible is covered with a crucible cover, the crucible cover is provided with a through hole, and the conductive capillary passes through the through hole.
[0015] In one of the embodiments, a corundum sleeve is embedded in the through hole, and the conductive capillary passes through the corundum sleeve and is slidably connected thereto.
[0016] The above-mentioned surface tension measuring instrument utilizes the conductive properties of the liquid to be measured by adding an LCR bridge and a conductive rod, and electrically connecting the conductive rod and the conductive capillary to the LCR bridge respectively. When the conductive capillary is lowered to contact the liquid to be measured, a closed loop is formed between the LCR bridge, the conductive rod, the liquid to be measured and the conductive capillary. After receiving the electrical signal, the LCR bridge automatically and accurately records the zero position. Starting from the zero position, the further movement of the conductive capillary is the depth of its immersion in the sample to be measured, thereby ensuring the accuracy of the depth data to improve the measurement accuracy of the surface tension measuring instrument of the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 A front view of one embodiment of the surface tension tester of the present application;
[0018] Figure 2 A cross-sectional view of a heating furnace portion in another embodiment of the surface tension tester of the present application;
[0019] Figure 3 This is a schematic diagram of the movement process of the measuring structure during the measurement process of the surface tension tester of this application;
[0020] Figure 4 for Figure 1 Right view of the middle lifting mechanism;
[0021] Figure 5 for Figure 2 Enlarged view of the measuring cylinder.
[0022] Figure numerals: 10, frame; 20, measuring tube; 21, connecting rod; 21a, thermal insulation plate; 22, lifting basket; 23, crucible; 23a, crucible cover; 23b, corundum sleeve; 30, lifting structure; 31, first lifting assembly; 31a, first base member; 31b, first driving member; 31c, first moving member; 32, second lifting assembly; 32a, second base member; 32b, second driving member; 32c, second moving member; 40, measuring structure; 41, LCR bridge; 42, conductive rod; 43, conductive capillary; 45, micro differential pressure gauge; 46, needle valve; 50, heating furnace. DETAILED DESCRIPTION
[0023] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.
[0024] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.
[0025] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0026] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0027] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0028] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.
[0029] Please combine Figure 1 , Figure 2 as well as Figure 3 As shown, the present application first provides a surface tension tester, including a frame 10, a measuring cylinder 20, a lifting structure 30 and a measuring structure 40, the measuring cylinder 20 and the lifting structure 30 are both arranged on the frame 10, and the measuring cylinder 20 is used to accommodate the liquid to be tested; the measuring structure 40 includes an LCR bridge 41, a conductive rod 42, a conductive capillary 43, an air inlet pipe and a micro differential pressure gauge 45, the conductive capillary 43 is fixedly arranged at the moving end of the lifting structure 30, and the lifting structure 30 can drive the conductive capillary 43 to rise and fall, so as to control one end of the conductive capillary 43 to be immersed in or leave the liquid to be tested, and the other end of the conductive capillary 43 is connected to the air inlet pipe and the micro differential pressure gauge 45 at the same time; the end of the conductive rod 42 is immersed in the liquid to be tested, and the conductive rod 42 and the conductive capillary 43 are electrically connected to the LCR bridge 41 respectively, so that when the conductive capillary 43 is immersed in the liquid to be tested, a closed loop is formed between the LCR bridge 41, the conductive rod 42, the liquid to be tested and the conductive capillary 43.
[0030] In the present application, an LCR bridge 41 and a conductive rod 42 are added, and the conductive rod 42 and the conductive capillary 43 are electrically connected to the LCR bridge 41 respectively, and the conductive property of the liquid to be tested is utilized. When the conductive capillary 43 is lowered to contact the liquid to be tested, a closed loop is formed between the LCR bridge 41, the conductive rod 42, the liquid to be tested and the conductive capillary 43. After receiving the electrical signal, the LCR bridge automatically and accurately records the zero position. Starting from the zero position, the further movement of the conductive capillary 43 is the depth of its immersion in the sample to be tested, thereby ensuring the accuracy of the depth data to improve the measurement accuracy of the surface tension measuring instrument of the present application.
[0031] In some embodiments, the conductive capillary 43 is made of platinum, nickel, molybdenum or tantalum.
[0032] It should be noted that most of the capillaries in the prior art are made of quartz or metal tantalum tubes, which have poor ductility. Among them, tantalum tubes are prone to oxidation adhesion, while quartz tubes are prone to breakage.
[0033] Preferably, the conductive capillary 43 is made of platinum. The conductive capillary 43 made of platinum has good ductility, is not prone to oxidation adhesion, is not prone to breakage, and has better applicability.
[0034] In some embodiments, the conductive rod 42 is made of stainless steel.
[0035] Of course, the conductive capillary 43 and the conductive rod 42 may also be made of other materials as long as they are conductive, and this application does not make any further limitations here.
[0036] Please refer to Figure 2 As shown, in some embodiments, the frame 10 is also provided with a heating furnace 50, and the measuring tube 20 is arranged in the heating furnace 50; through the heating effect of the heating furnace 50, the surface tension of some high-temperature melts can be measured to improve the versatility of the surface tension measuring instrument of the present application.
[0037] Please refer to Figure 4 As shown, in some embodiments, the lifting structure 30 includes a second lifting component 32 and a first lifting component 31, both of which can drive their own moving ends to move in the vertical direction; the first lifting component 31 is arranged on the frame 10, the second lifting component 32 is arranged at the moving end of the first lifting component 31, and the conductive capillary 43 is fixed at the moving end of the second lifting component 32.
[0038] The first lifting assembly 31 drives the measuring cylinder 20 to rise and fall, so that the measuring cylinder 20 can be inserted into or removed from the heating furnace 50 to facilitate the placement and removal of high-temperature samples to be tested; the second lifting assembly 32 can drive the conductive capillary 43 to rise and fall relative to the measuring cylinder 20 to enable the conductive capillary 43 to be inserted into the measuring cylinder 20.
[0039] Specifically, the first lifting assembly 31 includes a first base member 31a, a first driving member 31b and a first moving member 31c (i.e., a moving end of the first lifting assembly 31), wherein the first base member 31a is fixed to the frame 10, the first moving member 31c is slidably connected to the first base member 31a along the vertical direction, and the first driving member 31b is disposed on the first base member 31a and can drive the first moving member 31c to move relative to the first base member 31a along the vertical direction;
[0040] The second lifting component 32 includes a second base member 32a, a second driving member 32b and a second moving member 32c (i.e., the moving end of the second lifting component 32), wherein the second base member 32a is fixed to the first moving member 31c, the second moving member 32c is slidably connected to the second base member 32a along the vertical direction, the second driving member 32b is arranged on the second base member 32a, and can drive the second moving member 32c to move relative to the second base member 32a along the vertical direction, and the conductive capillary 43 is fixed to the second moving member 32c.
[0041] Please refer to Figure 5 As shown, in some embodiments, the measuring tube 20 includes a connecting rod 21, a lifting basket 22 and a crucible 23. The center of the connecting rod 21 passes through in the vertical direction, and one end of the connecting rod 21 is fixed to the lifting basket 22, and the other end is fixed to the movable end of the first lifting assembly 31. The crucible 23 is detachably arranged on the lifting basket 22; the conductive capillary 43 passes through the connecting rod 21.
[0042] The crucible 23 and the lifting basket 22 are clearance-matched, and when the measuring tube 20 is moved out of the heating furnace 50 driven by the first lifting assembly 31 , the crucible 23 can be replaced relatively simply.
[0043] Please refer to Figure 5 As shown, in some embodiments, a plurality of heat insulating sheets 22a are fixed on the connecting rod 21 at intervals in the vertical direction. When the crucible 23 is located in the heating furnace 50, the heat insulating sheets 22a can block the opening of the heating furnace 50 to prevent the measuring components above from being damaged due to the rising heat in the heating furnace 50.
[0044] Please refer to Figure 3 As shown, in some embodiments, the crucible 23 is covered with a crucible cover 23a, the crucible cover 23a is provided with a through hole, and the conductive capillary 43 passes through the through hole; the crucible cover 23a can also play a certain role in blocking heat.
[0045] Please refer to Figure 3 As shown, in some embodiments, a corundum sleeve 23b is embedded in the through hole, and the conductive capillary 43 passes through the corundum sleeve 23b and is slidably connected thereto; the corundum material is non-conductive and will not affect the formation of a closed loop; in addition, the sliding connection between the corundum sleeve 23b and the conductive capillary 43 can provide a certain limiting support for the conductive capillary 43, thereby improving the stability of the movement of the conductive capillary 43 and further increasing the measurement accuracy of the surface tension measuring instrument of the present application.
[0046] In some embodiments, the length of the conductive rod 42 is greater than that of the conductive capillary 43 to ensure that the end is always immersed in the sample to be tested. The crucible cover 23a is also embedded with another corundum sleeve 23b that is slidably connected to the conductive rod 42. The conductive rod 42 passes through the second movable member 32c and the corresponding corundum sleeve 23b, and the bottom end is against the bottom wall of the crucible 23.
[0047] Some melt high-temperature tests require inert gas protection to prevent high-temperature reactions; the heating furnace 50 is provided with a gas inlet, and the inert gas can be supplied to the heating furnace 50 by turning on the gas supply switch, thereby ensuring that the measurement process can be carried out in an inert gas environment and ensuring the safety of the measurement process.
[0048] Specifically, when the sample to be tested is a high-temperature melt, the method of using the surface tension measuring instrument of the present application is as follows:
[0049] 1. Sample loading: Load the prepared sample to be tested into the crucible, and ensure that the height of the melt in the crucible 23 after melting is 3 cm to 5 cm. The specific operation is to open the sealing device of the heating furnace 50, use the computer to control the first lifting assembly 31 to move up, lift the crucible 23 out of the heating furnace 50, load the crucible 23 containing the sample to be tested into the basket 22, use the computer to control the first lifting assembly 31 to move down, send the sample to be tested in the crucible 23 to the constant temperature zone of the heating furnace 50, and close the sealing device of the heating furnace 50;
[0050] 2. Turn on the circulating water and gas: Turn on the circulating water and introduce high-purity (purity higher than 99.8%) argon or nitrogen into the heating furnace 50;
[0051] 3. Install the measuring parts: Install the conductive rod 42 and the conductive capillary 43. The specific operation is to pass the conductive capillary 43 through the second movable part 32c and the corresponding corundum sleeve 23b, fix the conductive capillary 43 to the first movable part 31, and make its lower end float above the melt; pass the conductive rod 42 through the second movable part 32c and the corresponding corundum sleeve 23b until its lower end abuts against the bottom wall of the crucible 23.
[0052] 4. Set the temperature curve: Use computer control. The first section of the temperature curve is generally from the initial furnace temperature to the highest temperature, with a heating rate of 5 to 10°C / min. The second section is a constant temperature period, generally not less than 100 minutes. Then set the cooling curve with a cooling rate of 1 to 3°C / min. Multiple sections of heating-constant temperature-cooling can be set according to measurement needs.
[0053] 5. Measurement: 10 minutes before the end of the constant temperature, connect the circuit of the LCR bridge 41 and power it on; the needle valve 46 on the air inlet pipe controls the introduction of experimental gas into the conductive capillary 43; the second lifting assembly 32 controls the conductive capillary 43 to slowly descend to above the melt surface, and the computer records this position as the initial position. At this time, due to the high temperature and high pressure, there is a pressure difference P0 between the pressure inside the tube and the outside pressure, and the computer automatically reads the P0 measured by the micro differential pressure gauge 45;
[0054] 5.1: The second lifting assembly 32 continues to control the conductive capillary 43 to slowly descend. When the resistance of the LCR bridge 41 changes suddenly, the computer automatically records it as zero position;
[0055] 5.2: The second lifting assembly 32 controls the conductive capillary 43 to continue to descend to the target depth, and records the immersion depth h starting from the zero position;
[0056] 5.3: After the bubbles in the conductive capillary 43 are stable, the computer automatically reads the maximum differential pressure P measured by the micro differential pressure gauge 45. max , and calculate the surface tension at the real temperature:
[0057]
[0058] therefore,
[0059] 5.4: The second lifting assembly 32 controls the conductive capillary 43 to slowly rise to the initial position;
[0060] 5.5: Before the next constant temperature point ends, automatically repeat 5.1 to 5.4 operations to complete the surface tension-temperature measurement.
[0061] 6. End of measurement: Take out the conductive rod 42 and the conductive capillary 43 from the melt before the melt solidifies. When the furnace temperature is lower than 200°C, the circulation of water and gas can be stopped.
[0062] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0063] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.
Claims
1. A surface tension tester, characterized in that: It comprises a frame (10), a measuring cylinder (20), a lifting structure (30) and a measuring structure (40), wherein the measuring cylinder (20) and the lifting structure (30) are both arranged on the frame (10), and the measuring cylinder (20) is used to contain a liquid to be measured; The measuring structure (40) comprises an LCR bridge (41), a conductive rod (42), a conductive capillary (43), an air inlet pipe and a micro differential pressure gauge (45); the conductive capillary (43) is fixedly arranged at the moving end of the lifting structure (30); the lifting structure (30) can drive the conductive capillary (43) to move up and down, so as to control one end of the conductive capillary (43) to be immersed in or leave the liquid to be measured; the other end of the conductive capillary (43) is simultaneously connected to the air inlet pipe and the micro differential pressure gauge (45); The end of the conductive rod (42) is immersed in the liquid to be measured, and the conductive rod (42) and the conductive capillary (43) are respectively connected to the LCR bridge (41), so that when the conductive capillary (43) is immersed in the liquid to be measured, a closed loop is formed between the LCR bridge (41), the conductive rod (42), the liquid to be measured and the conductive capillary (43).
2. The surface tension tester according to claim 1, characterized in that: The conductive capillary (43) is made of platinum, nickel, molybdenum or tantalum.
3. The surface tension tester according to claim 1, characterized in that: The conductive rod (42) is made of stainless steel.
4. The surface tension tester according to claim 1, characterized in that: The frame (10) is also provided with a heating furnace (50), and the measuring cylinder (20) is arranged in the heating furnace (50).
5. The surface tension tester according to claim 4, characterized in that: The lifting structure (30) comprises a first lifting component (31) and a second lifting component (32), both of which are capable of driving their own moving ends to move in a vertical direction; the first lifting component (31) is arranged on the frame (10), the second lifting component (32) is arranged on the moving end of the first lifting component (31), and the conductive capillary (43) is fixedly arranged on the moving end of the second lifting component (32).
6. The surface tension tester according to claim 5, characterized in that: The first lifting component (31) comprises a first base member (31a), a first driving member (31b) and a first moving member (31c), wherein the first base member (31a) is fixed to the frame (10), the first moving member (31c) is slidably connected to the first base member (31a) along a vertical direction, and the first driving member (31b) is arranged on the first base member (31a) and is capable of driving the first moving member (31c) to move relative to the first base member (31a) along a vertical direction; The second lifting component (32) comprises a second base member (32a), a second driving member (32b) and a second moving member (32c), wherein the second base member (32a) is fixedly mounted on the first moving member (31c), the second moving member (32c) is slidably connected to the second base member (32a) along a vertical direction, the second driving member (32b) is arranged on the second base member (32a) and is capable of driving the second moving member (32c) to move along a vertical direction relative to the second base member (32a), and the conductive capillary (43) is fixedly mounted on the second moving member (32c).
7. The surface tension tester according to claim 5, characterized in that: The measuring cylinder (20) comprises a connecting rod (21), a lifting basket (22) and a crucible (23); the center of the connecting rod (21) passes through in a vertical direction, one end of the connecting rod (21) is fixed to the lifting basket (22), and the other end is fixed to the movable end of the first lifting assembly (31); the crucible (23) is detachably arranged on the lifting basket (22); and the conductive capillary (43) passes through the connecting rod (21).
8. The surface tension tester according to claim 7, characterized in that: A plurality of heat insulating sheets (22a) are fixed on the connecting rod (21) at intervals in the vertical direction.
9. The surface tension tester according to claim 7, characterized in that: The crucible (23) is covered with a crucible cover (23a), the crucible cover (23a) is provided with a through hole, and the conductive capillary (43) passes through the through hole.
10. The surface tension tester according to claim 9, characterized in that: A corundum sleeve (23b) is embedded in the through hole, and the conductive capillary (43) passes through the corundum sleeve (23b) and is slidably connected thereto.