A titration device

Abstract

The utility model discloses a titration device belongs to titrimetric analysis technical field, the utility model discloses a titration device includes: mounting bracket, the liquid storage bottle and reaction bottle of placing on mounting bracket, through the support setting on mounting bracket, and its titration burette is located the top of reaction bottle, and the bottom end of titration burette is provided with titration control valve, the buffer liquid pipe, including the tubular body, the liquid outlet pipe and liquid inlet pipe, and the liquid outlet pipe is connected with titration burette, and the liquid inlet pipe is connected with the liquid storage bottle, and the valve is set up on the liquid inlet pipe and liquid outlet pipe. The plunger rod that forms coaxial with the tubular body inner wall and sliding fit. Still include with the drive connection of plunger rod drive mechanism, and drive mechanism is built -in or is connected with displacement sensor. The utility model discloses discarded traditional titration in the cumbersome manual control flow rate, visual reading, manual record volume and frequent bottle / liquid supplementing operation, reduce artificial error, improve experimental efficiency and reliability.

Description

Technical Field

[0001] This utility model relates to the field of titration analysis, and in particular to a titration apparatus. Background Technology

[0002] Traditional titration requires the use of a burette. The operator manually controls the flow rate of the titrant by rotating the burette stopcock or squeezing the glass bead, and visually determines the volume by reading the scale on the burette. As titration proceeds, the liquid level in the burette drops, causing the flow rate to slow down. The operator must adjust the burette stopcock opening or control the pressure applied to the glass bead to maintain a constant flow rate. This is not only cumbersome but also inevitably introduces flow rate fluctuations, affecting the determination of the reaction endpoint. Furthermore, determining the titrant volume relies entirely on the operator's visual reading of the liquid level in the burette, inevitably introducing parallax and estimation errors. Utility Model Content

[0003] This invention provides a titration device that can precisely control the flow rate of the titrant during the titration process and ensure the accuracy of the titration results.

[0004] The technical solution of this utility model is as follows:

[0005] The titration apparatus includes:

[0006] Mounting rack;

[0007] The liquid storage bottle is placed on the mounting rack;

[0008] The reaction flask is placed on the mounting rack;

[0009] The burette is mounted on the mounting bracket via a support, with its dispensing port located above the reaction flask; a titration control valve is installed at the bottom of the burette.

[0010] The buffer fluid tubing is fixedly mounted on the mounting bracket; the buffer fluid tubing includes:

[0011] - A cylindrical tube, with one end open and the other end closed;

[0012] - The liquid outlet tube is located at the closed end of the cylindrical tube and is connected to the upper port of the burette through a pipeline; an outlet valve is provided on the liquid outlet tube.

[0013] - The inlet pipe is located on the side wall of the cylindrical tube and near the closed end, and is connected to the storage bottle through a pipeline; an inlet valve is provided on the inlet pipe;

[0014] The plunger rod forms a coaxial and sealed sliding fit with the inner wall of the cylindrical tube of the buffer fluid tube;

[0015] The drive mechanism, mounted on the mounting bracket and connected to the plunger rod drive, is used to drive the plunger rod to move axially within the cylindrical tube. The drive mechanism has a built-in or connected displacement sensor for precisely controlling the reciprocating linear motion of the plunger rod within the cylindrical tube along the axial direction of the cylindrical tube.

[0016] The control box is placed on the mounting bracket; the control box is electrically connected to the titration control valve, inlet valve, outlet valve and drive mechanism respectively.

[0017] According to the aforementioned titration apparatus, the mounting frame includes a base plate and a support plate located on the upper surface of the base plate and perpendicular to the base plate;

[0018] The storage bottles, reaction flasks, and control box are placed on the base plate;

[0019] The burette is mounted on a support plate via a bracket;

[0020] The buffer fluid tube and drive mechanism are mounted on the support plate.

[0021] Furthermore, the stent includes:

[0022] The bracket is fixed to the support plate;

[0023] A linkage assembly, which consists of multiple links that are hinged together in sequence;

[0024] Clamps are used to hold burettes;

[0025] The first end of the linkage assembly is hinged to the support base, and the second end of the linkage assembly is equipped with a clamp.

[0026] The linkage assembly is configured to adjust the position and / or attitude of the clamp relative to the support by changing the relative angles between multiple links.

[0027] Furthermore, the fixture includes:

[0028] The fastener has a first arcuate portion extending along a first direction and a first fixing portion extending from the first arcuate portion; the first fixing portion has a first through hole penetrating its thickness;

[0029] The movable part has a second arc-shaped portion extending along a first direction and a second fixed portion extending from the second arc-shaped portion; the first arc-shaped portion and the second arc-shaped portion are arranged opposite to each other and together define a clamping space for clamping the burette; the first fixed portion and the second fixed portion are hinged to each other by a hinge shaft; the second fixed portion has a second through hole that penetrates its thickness;

[0030] The connecting rod has one end hinged to the second end of the connecting rod assembly, and the other end fixedly connected to the first fixing part of the fixing member;

[0031] The connecting bolt has its threaded portion passing through the first through hole on the first fixing part and the second through hole on the second fixing part in sequence; its nut portion is located on the side of the first fixing part away from the second fixing part and abuts against the surface of that side.

[0032] The adjusting nut is threaded onto the threaded part of the connecting bolt and is located on the side of the second fixing part away from the first fixing part, and abuts against the surface of that side.

[0033] A spring is fitted onto the threaded portion of the connecting bolt, with its two axial ends abutting against the side of the first fixing part facing the second fixing part and the side of the second fixing part facing the first fixing part, respectively, applying an elastic force to the first fixing part and the second fixing part to move them away from each other.

[0034] According to the aforementioned titration apparatus, the driving mechanism includes:

[0035] The first bearing bracket is fixedly mounted on the support plate;

[0036] The second bearing bracket is fixed on the support plate and is arranged parallel and spaced apart from the first bearing bracket.

[0037] The lead screw is rotatably connected between the first bearing bracket and the second bearing bracket;

[0038] The motor is fixed on the support plate and electrically connected to the control box;

[0039] The speed reducer connects the motor and the lead screw at one end;

[0040] The movable seat is threadedly connected to the circumferential surface of the lead screw;

[0041] The end of the plunger rod furthest from the buffer fluid tube is fixedly connected to the movable seat, and the buffer fluid tube is fixedly mounted on the second bearing bracket;

[0042] The motor drives the lead screw to rotate, which in turn drives the moving seat to move along the lead screw axis, which in turn drives the plunger rod to move relative to the cylindrical tube.

[0043] Furthermore, the drive mechanism also includes a slide rail between the first bearing bracket and the second bearing bracket, on which the movable seat slides.

[0044] The titration apparatus described above also includes an electromagnetic stirrer placed on a base plate, and a reaction flask placed on the electromagnetic stirrer; a stirring magnet is placed inside the reaction flask.

[0045] The electromagnetic stirrer is electrically connected to the control box.

[0046] The aforementioned titration apparatus also includes a color sensor fixed to a base plate or support plate, and the color sensor is electrically connected to the control box.

[0047] Furthermore, it also includes:

[0048] The lighting fixture is fixed on the support plate and is electrically connected to the control box.

[0049] The background plate is vertically fixed to the base plate; the reaction flask is located between the lighting lamp and the background plate.

[0050] According to the aforementioned titration apparatus, the control box includes:

[0051] - Controller;

[0052] - Control panel, which includes a power switch, flow rate adjustment knob and display screen;

[0053] - The battery, located inside the control box, is used to provide power;

[0054] The controller is electrically connected to the titration control valve, inlet valve, outlet valve, and drive mechanism.

[0055] The titration apparatus provided by this utility model has at least the following advantages compared with the prior art:

[0056] (1) The titration device of this utility model completely eliminates the cumbersome manual control of flow rate, visual reading, manual recording of volume and frequent bottle changing / liquid replenishment operations in traditional titration through the combined structure design of buffer liquid tube, plunger rod, drive mechanism and control box, thereby reducing human error and improving experimental efficiency and reliability.

[0057] (2) All components of the titration device of this utility model are integrated on the mounting frame. The structure is reasonable and compact, with strong integrity, and is easy to move, place and manage. Attached Figure Description

[0058] Figure 1 A three-dimensional structural diagram of a titration apparatus;

[0059] Figure 2 for Figure 1 A magnified view of a section at point A in the middle;

[0060] Figure 3 A front view of a titration apparatus;

[0061] Figure 4 A three-dimensional schematic diagram of another titration apparatus;

[0062] Figure 5 A three-dimensional structural diagram showing the combined state of the support plate, buffer fluid tube, plunger rod, and drive mechanism;

[0063] Figure 6 A cross-sectional view of the combined support plate, buffer fluid tube, plunger rod, and drive mechanism;

[0064] Figure 7 This is a schematic diagram of the three-dimensional structure of the fixture.

[0065] Explanation of reference numerals in the attached figures:

[0066] 1. Mounting bracket; 11. Base plate; 12. Support plate; 2. Storage bottle; 3. Reaction flask; 4. Burette; 41. Titration control valve; 5. Bracket; 51. Bracket base; 52. Linkage assembly; 53. Clamp; 531. Fixture; 532. Moving part; 533. Connecting rod; 534. Connecting bolt; 535. Adjusting nut; 536. Spring; 6. Buffer tube; 61. Cylindrical tube body; 62. Outlet tube; 63. Outlet valve; 64. Inlet tube; 65. Inlet valve; 7. Plunger rod; 8. Drive mechanism; 81. First bearing bracket; 82. Second bearing bracket; 83. Lead screw; 84. Motor; 85. Reducer; 86. Moving base; 87. Slide rail; 9. Control box; 91. Power switch; 92. Flow rate adjustment knob; 93. Display screen;

[0067] 100. Electromagnetic stirrer; 200. Stirring magnet; 300. Color sensor; 400. Lighting lamp; 500. Background board;

[0068] 531a, First arc-shaped portion; 531b, First fixing portion; 531c, First through hole; 532a, Second arc-shaped portion; 532b, Second fixing portion; 532c, Second through hole. Detailed Implementation

[0069] To make the technical problem to be solved, the technical solution and advantages of this utility model clearer, the following will be described in conjunction with the accompanying drawings. Figures 1 to 7 The technical solution of this utility model is clearly and completely described in conjunction with specific embodiments.

[0070] The titration apparatus of this utility model embodiment is as follows: Figures 1 to 3 As shown, the device includes a mounting frame 1, a storage bottle 2, a reaction flask 3, a burette 4, a support 5, a buffer solution tube 6, a plunger rod 7, a drive mechanism 8, and a control box 9. The mounting frame 1 serves as a support structure, mounting the other components of the device. The storage bottle 2, placed on the mounting frame 1, is used to store the titrant. The reaction flask 3, placed on the mounting frame 1, is used to hold the sample to be tested and to perform the titration reaction. The burette 4, mounted on the mounting frame 1 via the support 5, has its dispensing port located above the reaction flask 3, and is used to add the titrant to the reaction flask 3.

[0071] The storage bottle 2 can be replenished or replaced at any time during device operation, completely eliminating the long-term manual interruption caused by the main storage bottle running out of liquid in traditional titration. Users only need to ensure that the storage bottle has liquid, and the device will automatically complete the buffer replenishment.

[0072] The buffer liquid tube 6 is fixedly mounted on the mounting bracket 1. The main structure of the buffer liquid tube 6 is a cylindrical tube body 61, with one end open and the other end closed, forming a plunger cavity. An outlet pipe 62 is provided at the closed end of the cylindrical tube body 61, which is connected to the upper port of the burette 4 via a connecting pipe. An inlet pipe 64 is provided on the side wall of the cylindrical tube body 61 near the closed end, and is connected to the storage bottle 2 via a connecting pipe. An outlet valve 63 is provided on the outlet pipe 62 to control the liquid flow from the buffer liquid tube 6 to the burette 4. An inlet valve 65 is provided on the inlet pipe 64 to control the liquid flow from the storage bottle 2 to the buffer liquid tube 6. The outlet pipe 62 and the inlet pipe 64 are respectively connected to the inner cavity of the cylindrical tube body 61. The working chamber volume of the cylindrical tube 61 is designed to be greater than the minimum replenishment volume required for a single titration, and is typically set to support continuous titrations for several minutes or even longer.

[0073] The plunger rod 7 is slidably inserted into the open end of the cylindrical tube 61, and its outer diameter forms a coaxial and dynamically sealed sliding fit with the inner wall of the cylindrical tube 61 (e.g., achieved through a sealing ring or precision fit), thereby dividing the cylindrical tube 61 into a working chamber near the closed end and a driving chamber near the open end. The axial movement of the plunger rod 7 changes the volume of the working chamber.

[0074] A titration control valve 41 is installed at the bottom of the burette 4 at the dispensing port. The burette 4 is always filled with liquid (i.e., there are no air bubbles in the burette and the liquid level is constant at the top of the tube), achieving constant hydrostatic pressure. Combined with the constant speed advancement of the plunger rod 7, a stable flow source is formed, and the flow rate is determined only by the moving speed of the plunger rod 7, unaffected by the drop in liquid level. In addition, it ensures that there are always no air bubbles in the burette, eliminating the need for repeated air venting steps in traditional titration.

[0075] The buffer liquid tube 6, its plunger rod 7, and the drive mechanism 8 are the core units for actively delivering the titrant. The core unit draws a large volume of titrant (single aspiration volume) from the storage bottle 2, then, during the dispensing stage, forces it into the burette 4 at a precisely controlled flow rate and finally drips it into the reaction flask 3.

[0076] The drive mechanism 8 is mounted on the mounting bracket 1 and is drivenly connected to the end of the plunger rod 7 away from the working chamber. The drive mechanism 8 includes, but is not limited to, linear drive components such as cylinders, hydraulic cylinders, and electric actuators, as long as they can provide linear driving force. The drive mechanism 8 is preferably a precision linear actuator, such as a ball screw mechanism driven by a stepper motor or servo motor, used to precisely control the reciprocating linear motion of the plunger rod 7 along its axial direction within the cylindrical tube 61. The drive mechanism 8 has a built-in or connected displacement sensor (such as an encoder, grating ruler, or linear variable differential transformer LVDT) for precisely controlling the reciprocating linear motion of the plunger rod 7 along its axial direction within the cylindrical tube 61 and for real-time monitoring of the displacement L and movement speed v of the plunger rod 7.

[0077] The control box 9 is placed on the mounting bracket 1. The control box 9 includes a controller (e.g., a microprocessor or microcontroller), a control panel, and a battery. The control panel is fixed to the surface of the control box 9 and includes a power switch 91, a flow rate adjustment knob 92, and a display screen 93. The power switch 91 is used to turn the power to the entire device on or off. The flow rate adjustment knob 92 is used to set the target titration flow rate; the display screen 93 is used to display the current flow rate, the volume of titrant added to the reaction flask 3, the working status (e.g., "titration in progress," "liquid aspiration in progress"), the plunger position, and other information. The battery is located inside the control box 9 and provides power to the controller, the drive mechanism 8, the outlet valve 63, and the display screen 93; the controller is electrically connected to the titration control valve 41, the inlet valve 65, the outlet valve 63, and the drive mechanism 8 via signal lines.

[0078] The controller coordinates the actions of the titration control valve 41, outlet valve 63, inlet valve 65 and drive mechanism 8 according to the set target flow rate and operation instructions, including the liquid aspiration stage and the titration stage.

[0079] The liquid aspiration stage is specifically as follows: the controller opens the inlet valve 65, closes the outlet valve 63, and controls the drive mechanism 8 to move the plunger rod 7 away from the closed end (reverse aspiration). At this time, the working chamber volume increases, generating negative pressure, which draws the titrant from the storage bottle 2 into the working chamber of the buffer tube 6 through the inlet pipe 64. During this stage, no liquid is supplied to the burette 4. When the maximum amount of liquid aspiration is reached, the controller closes the inlet valve 65.

[0080] The titration stage is as follows: the controller opens the outlet valve 63 and the titration control valve 41, closes the inlet valve 65, and controls the drive mechanism 8 to move (advance) the plunger rod 7 towards the closed end, keeping the burette 4 full of liquid. At this time, the working chamber volume decreases, forcing the titrant into the burette 4 through the outlet pipe 62 and connecting pipe, and finally dripping from the dripping port of the burette 4 into the reaction flask 3 at a set flow rate. The advancement speed of the drive mechanism 8 directly controls the discharge flow rate. Upon reaching the titration endpoint, the controller simultaneously performs three actions: closing the titration control valve 41, stopping the plunger advancement of the drive mechanism 8, and closing the outlet valve 63. The liquid path is physically isolated within 0.5 seconds, completely blocking the dripping of liquid.

[0081] The amount of titrant added to reaction flask 3 is determined by the stroke of the plunger rod 7 driven by the drive mechanism 8, which can be calculated as follows:

[0082] The effective cross-sectional area S of the working chamber of the cylindrical tube 61 is a known and constant design parameter (determined by the inner diameter of the cylindrical tube 61). The displacement ΔL of the plunger rod 7 during the titration stage is accurately measured by the displacement sensor of the drive mechanism 8 and transmitted to the controller in real time. The volume of titrant added to the reaction flask 3, ΔV, is calculated using the following formula:

[0083] ΔV=S×ΔL

[0084] Before titration, the experimenter adds an indicator to reaction flask 3, then adds titrant to flask 3. Titration stops when the indicator changes color. The titration endpoint can be determined by visually observing the color change of the liquid in reaction flask 3 or by using a detection sensor. The volume of titrant ΔV recorded by the controller is the volume of titrant consumed. The controller displays the volume of titrant ΔV on display screen 93. By directly measuring the plunger displacement and the effective cross-sectional area S of the working chamber of the cylindrical tube 61, the volume of titrant is converted into the volume of titrant, avoiding errors from manual visual reading and improving the accuracy of the test.

[0085] All major components are integrated on mounting bracket 1, with a reasonable and compact structural layout, strong overall integrity, and easy to move, place, and manage.

[0086] Mounting bracket 1 includes a base plate 11 and a support plate 12 located on the upper surface of the base plate 11 and perpendicular to the base plate 11. A storage bottle 2, a reaction flask 3, and a control box 9 are placed on the base plate 11. A burette 4 is mounted on the support plate 12 via a bracket 5. A buffer solution tube 6 and a drive mechanism 8 are mounted on the support plate 12.

[0087] The support 5 is used to flexibly and stably position and support the burette 4 in space. The structure of the support 5 includes a support base 51, a connecting rod assembly 52, and a clamp 53, as shown below. Figure 1 and Figure 2As shown. The support base 51 serves as the fixed base of the support 5, rigidly fixed to the support plate 12, providing a stable installation foundation for the entire support. The support base 51 and the support plate 12 can be fixed by bolt connection, welding, or integral molding. The support base 51 is provided with a first hinge point for connecting to the first end of the connecting rod assembly 52. ​​The connecting rod assembly 52 is composed of multiple connecting rods (such as connecting rod A, connecting rod B, connecting rod C, etc.) connected in sequence by hinges. Adjacent connecting rods are rotatably connected and can be locked through hinge shafts (such as pins or spherical bearings). The connecting rod assembly 52 is existing technology and will not be described in detail here. In this embodiment of the present invention, two connecting rods are used as an example. The first end of the connecting rod assembly 52 (i.e., the end of the starting connecting rod near the support base) is hinged to the first hinge point on the support base 51 through a hinge shaft, so that the connecting rod assembly 52 can rotate relative to the support base 51. The second end of the connecting rod assembly 52 is provided with a second hinge point for connecting to the clamp 53. The clamp 53 is used to hold the burette 4. The clamp 53 is hinged to the second end of the connecting rod assembly 52 via its connecting rod 533. This allows the clamp 53 to swing at a certain angle relative to the end of the connecting rod assembly 52. ​​By manually changing the relative angles between the multiple connecting rods within the connecting rod assembly 52 (i.e., adjusting the joint angles at adjacent hinge points), the spatial position of the clamp 53 relative to the support base 51 is adjusted, changing the tilt angle of the clamp 53 and the burette 4 it holds. This ensures that the dispensing nozzle of the burette 4 is vertically aligned with the center of the reaction flask 3 below, or can be adjusted to a specific tilt angle according to experimental requirements. After adjustment, the connecting rod assembly 52 can maintain structural stability at each hinge point through friction self-locking, the installation of locking screws, or the design of a center dead point structure, preventing displacement under gravity or operational vibration.

[0088] Furthermore, the structure of fixture 53 is as follows: Figure 7As shown. The clamp 53 includes a fixed member 531, a movable member 532, a connecting rod 533, and a clamping force adjustment mechanism. The fixed member 531 has a first arc-shaped portion 531a, the concave surface of which is adapted to the contour of the outer wall of the burette. The fixed member 531 has a first fixing portion 531b extending radially outward from the first arc-shaped portion 531a. A first through hole 531c penetrating the thickness of the first fixing portion 531b is provided on the first fixing portion 531b. The movable member 532 has a second arc-shaped portion 532a, the concave surface of which is opposite to the first arc-shaped portion 531a, together forming a complete annular or near-annular clamping surface. The movable member 532 has a second fixing portion 532b extending radially outward from the second arc-shaped portion 532a. The first fixing portion 531b and the second fixing portion 532b are hingedly connected by a hinge shaft, allowing the movable member 532 to rotate and open relative to the fixed member 531 about the hinge shaft. The second fixing part 532b has a second through hole 532c extending through its thickness. One end of the connecting rod 533 is hinged to the second end of the connecting rod assembly 52 via a pin or ball joint, receiving motion transmission from the drive mechanism. The other end of the connecting rod 533 is fixedly connected (e.g., welded, riveted, or integrally formed) to the first fixing part 531b of the fixing member 531, thereby linking the fixing member 531 with the external drive mechanism. The clamping force adjustment mechanism includes a connecting bolt 534, an adjusting nut 535, and a spring 536. The threaded portion of the connecting bolt 534 passes sequentially through the first through hole 531c of the first fixing part 531b and the second through hole 532c of the second fixing part 532b. The nut portion of the connecting bolt 534 is located on the outer surface of the first fixing part 531b, facing away from and abutting against it. An adjusting nut 535 is threaded onto the threaded portion of the connecting bolt 534, located on and abutting against the outer surface of the second fixed portion 532b, which faces away from the first fixed portion 531b. By tightening the adjusting nut 535, the pressure it exerts on the second fixed portion 532b can be changed, thereby adjusting the degree of closure and clamping force of the movable member 532 relative to the fixed member 531. A spring 536 is sleeved on the threaded portion of the connecting bolt 534 and is pre-compressed between the first fixed portion 531b and the second fixed portion 532b. The first end of the spring 536 abuts against the inner surface of the first fixed portion 531b facing the second fixed portion 532b, and the second end of the spring 536 abuts against the inner surface of the second fixed portion 532b facing the first fixed portion 531b. The spring 536 is always in a compressed state, generating an elastic restoring force that causes the first fixed portion 531b and the second fixed portion 532b to move away from each other, i.e., a tendency for the movable member 532 to rotate in the opening direction about the hinge axis.

[0089] When it is necessary to clamp the burette 4, tighten the adjusting nut 535 to overcome the elastic force of the spring 536, pushing the second fixing part 532b closer to the first fixing part 531b. This causes the movable part 532 to close around the hinge axis of the fixing part 531, so that the first arc-shaped part 531a and the second arc-shaped part 532a together grip the outer wall of the burette 4. The clamping force is precisely controlled by the tightness of the adjusting nut 535. When it is necessary to release the burette 4, loosen the adjusting nut 535. The restoring force of the spring 536 quickly pushes the second fixing part 532b away from the first fixing part 531b, driving the movable part 532 to automatically spring open around the hinge axis, releasing the burette 4.

[0090] The clamping space formed by the first arc-shaped portion 531a and the second arc-shaped portion 532a, adapted to the shape of the burette, combined with the clamping force adjustment mechanism, can firmly clamp burettes 4 of different diameters, effectively preventing them from shaking, sliding, or falling off during titration, ensuring the stability of the spatial position of the burette 4, and providing a fundamental guarantee for high-precision titration. By turning the adjusting nut 535, the tester can conveniently and continuously steplessly adjust the clamping force to accommodate burettes of different diameters, weights, or those with special clamping force requirements.

[0091] The following provides a specific structure for a drive mechanism 8. For example... Figure 5 and Figure 6 As shown, the drive mechanism 8 includes a first bearing bracket 81 and a second bearing bracket 82 rigidly fixed on the support plate 12. The support plate 12 is connected to the first bearing bracket 81 and the second bearing bracket 82 by bolts or welding. The second bearing bracket 82 is arranged parallel to and spaced apart from the first bearing bracket 81. The two ends of the lead screw 83 are rotatably supported on the first bearing bracket 81 and the second bearing bracket 82, respectively. The motor 84 is fixedly mounted on the support plate 12 and electrically connected to the controller of the control box 9, receiving speed, direction, and position commands from the controller. The motor 84 is preferably a stepper motor or a servo motor. The input end of the reducer 85 is connected to the output shaft of the motor 84, and its output end is rigidly connected to one end of the lead screw 83 coaxially via a coupling. The center of the moving seat 86 is provided with an internal threaded hole that matches the thread parameters of the lead screw 83, and the lead screw 83 is threadedly connected to the circumferential surface of the lead screw 83 through this internal threaded hole. The end of the plunger rod 7 away from the buffer fluid pipe 6 (i.e., the drive cavity end) is fixedly connected to the moving seat 86 by a rigid connector. The cylindrical tube 61 of the buffer liquid tube 6 is rigidly fixed to the second bearing bracket 82 to ensure that its position is absolutely fixed during operation. Specifically, the rigid connecting parts can be flanges, lock nuts, clamps, or brackets for locking, or welding can also be used.

[0092] The controller sends a start command to the motor 84. The rotation of the output shaft of the motor 84 is reduced in speed and increased in torque by the reducer 85, driving the lead screw 83 to rotate. The rotational motion of the lead screw 83 is converted into linear motion of the moving seat 86 along the axial direction of the lead screw 83 through the threaded joint. The moving seat 86 drives the plunger rod 7, which is fixedly connected to it, to move linearly in sync. The plunger rod 7 performs reciprocating linear motion (advancing or retracting) within the cylindrical tube 61, thereby controlling the change in the volume of the working chamber and realizing the quantitative intake and constant-speed discharge of the titrant.

[0093] The motor 84 is directly controlled by the controller in the control box 9. The displacement sensor built into the motor 84, such as a motor encoder or an additional grating ruler, provides real-time feedback to the controller on the precise position L and speed v of the plunger rod 7, forming a closed-loop control to ensure that the displacement and / or speed are consistent with the set values. The controller can dynamically adjust the operating parameters of the motor 84 in real time according to the set flow rate of the titrant, the target volume, or the endpoint signal, to achieve fully automatic and intelligent titration process control.

[0094] The drive mechanism 8 also includes a slide rail 87 between the first bearing bracket 81 and the second bearing bracket 82. The movable seat 86 slides on the slide rail 87, and the slide rail 87 restricts the movable seat 86 to translate only along the axial direction of the lead screw 83.

[0095] In the optional solutions of this embodiment, such as Figure 4 As shown, the titration apparatus also includes an electromagnetic stirrer 100 placed on a base plate 11. The reaction flask 3 is placed on the electromagnetic stirrer 100, and the reaction flask 3 is located within the effective working area of ​​the electromagnetic stirrer 100. A stirring magnet 200 is placed inside the reaction flask 3. The stirring magnet 200 is made of a corrosion-resistant material (such as a polytetrafluoroethylene-coated magnetic core) and can freely sink to the bottom of the reaction liquid. The electromagnetic stirrer 100 is electrically connected to the control box 9. The stirring speed (i.e., the magnetic field rotation rate) can be set and adjusted via the control panel of the control box 9 (e.g., by adding a stirring speed adjustment knob to the control panel or by setting it through a menu), and the current rotation speed value is displayed in real time on the display screen 93. The controller precisely controls the output power and frequency of the electromagnetic stirrer 100 according to the set values.

[0096] The use of the electromagnetic stirrer 100 and the stirring magnet 200 completely eliminates the tedious operation of manually inserting the stirring rod, adjusting the speed, or starting the stirring equipment midway, truly achieving full automation of the titration-stirring process. The precisely controlled constant stirring speed, combined with a stable environment free from mechanical interference, ensures highly consistent stirring conditions for each titration experiment, eliminating human errors caused by manual stirring (such as uneven force and speed), and greatly improving the repeatability and comparability of results from multiple parallel titration experiments.

[0097] In an optional embodiment, the titration apparatus further includes a color sensor 300 fixed on the base plate 11 or support plate 12, and the color sensor 300 is electrically connected to the controller of the control box 9. The color sensor 300 uses human-eye biomimetic color recognition technology to ensure stable monitoring of the solution color in the reaction flask 3, thereby improving the repeatability of the results and avoiding subjective errors in manual operation. During the dripping of the standard solution, when the color sensor 300 detects a change in the color of the solution in the reaction flask 3, it sends a command through the controller of the control box 9 to control the closing of the titration control valve 41, stop the plunger advance of the drive mechanism 8, and close the outlet valve 63. The operation process is simple, and the measurement results are accurate. In this embodiment, the titration endpoint is automatically identified by the color sensor 300, avoiding measurement errors caused by human operation. Specifically, the color sensor 300 can be an LR-W500 Keyence color sensor.

[0098] Furthermore, the titration apparatus also includes a lighting lamp 400 and a background plate 500. The lighting lamp 400 is fixed to the support plate 12 and is electrically connected to the controller of the control box 9. The background plate 500 is vertically fixed to the base plate 11, as shown below. Figure 4 As shown, reaction flask 3 is located between illumination lamp 400 and background plate 500. Background plate 500 can be white, effectively solving the problem of color change at the titration endpoint being affected by external colors during routine acid-base titrations. Illumination lamp 400 effectively solves the problem of color change at the titration endpoint being affected by laboratory lighting during acid-base titrations. The combined use of illumination lamp 400 and background plate 500 improves the accuracy of detection by color sensor 300.

[0099] In the description of this utility model, it should be understood that the terms "upper", "bottom", "inner", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0100] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0101] Finally, it should be noted that the above-described embodiments are merely specific implementations of this utility model, used to illustrate the technical solutions of this utility model, and not to limit it. The protection scope of this utility model is not limited thereto. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the technical scope disclosed in this utility model. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model, and should all be covered within the protection scope of this utility model.

Claims

1. A titration apparatus, characterized in that, include: Mounting bracket (1); The liquid storage bottle (2) is placed on the mounting bracket (1); The reaction flask (3) is placed on the mounting rack (1); The burette (4) is mounted on the mounting bracket (1) via a bracket (5), and its dispensing port is located above the reaction flask (3); a titration control valve (41) is provided at the bottom of the burette (4); A buffer fluid tube (6) is fixedly mounted on a mounting bracket (1); the buffer fluid tube (6) includes: - A cylindrical tube (61), one end of which is open and the other end is closed; - The liquid outlet pipe (62) is located at the closed end of the cylindrical tube (61) and is connected to the upper port of the burette (4) through a pipeline; an outlet valve (63) is provided on the liquid outlet pipe (62); - The inlet pipe (64) is located on the side wall of the cylindrical tube (61) and close to the closed end, and is connected to the storage bottle (2) through a pipeline; an inlet valve (65) is provided on the inlet pipe (64); The plunger rod (7) forms a coaxial and sealed sliding fit with the inner wall of the cylindrical tube body (61) of the buffer liquid tube (6); The drive mechanism (8) is mounted on the mounting bracket (1) and driven to connect with the plunger rod (7), and is used to drive the plunger rod (7) to move along its axial direction inside the cylindrical tube (61); the drive mechanism (8) has a built-in or connected displacement sensor, which is used to precisely control the plunger rod (7) to reciprocate linearly along the axial direction of the cylindrical tube (61) inside the cylindrical tube (61); The control box (9) is placed on the mounting bracket (1); the control box (9) is electrically connected to the titration control valve (41), the inlet valve (65), the outlet valve (63) and the drive mechanism (8).

2. The titration apparatus according to claim 1, characterized in that, The mounting bracket (1) includes a base plate (11) and a support plate (12) located on the upper surface of the base plate (11) and perpendicular to the base plate (11); The storage bottle (2), reaction bottle (3) and control box (9) are placed on the base plate (11); The burette (4) is mounted on the support plate (12) via a bracket (5); The buffer liquid tube (6) and the drive mechanism (8) are mounted on the support plate (12).

3. The titration apparatus according to claim 2, characterized in that, The stent (5) includes: The bracket (51) is fixed on the support plate (12); Linkage assembly (52), which includes a plurality of links that are hinged in sequence; Clamp (53) is used to hold the burette (4); The first end of the connecting rod assembly (52) is hinged to the support base (51), and the second end of the connecting rod assembly (52) is provided with a clamp (53). The linkage assembly (52) is configured to adjust the position and / or orientation of the clamp (53) relative to the support base (51) by changing the relative angle between the plurality of links.

4. The titration apparatus according to claim 3, characterized in that, The fixture (53) includes: The fastener (531) has a first arcuate portion (531a) extending along a first direction and a first fixing portion (531b) extending from the first arcuate portion (531a); the first fixing portion (531b) has a first through hole (531c) penetrating its thickness; The movable part (532) is provided with a second arcuate portion (532a) extending along a first direction and a second fixed portion (532b) extending from the second arcuate portion (532a); the first arcuate portion (531a) and the second arcuate portion (532a) are arranged opposite to each other and together define a clamping space for clamping the burette (4); the first fixed portion (531b) and the second fixed portion (532b) are hinged to each other by a hinge shaft; the second fixed portion (532b) is provided with a second through hole (532c) penetrating its thickness; The connecting rod (533) has one end hinged to the second end of the connecting rod assembly (52), and the other end is fixedly connected to the first fixing part (531b) of the fixing member (531). The connecting bolt (534) has its threaded portion passing through the first through hole (531c) on the first fixing part (531b) and the second through hole (532c) on the second fixing part (532b) in sequence; its nut portion is located on the side of the first fixing part (531b) away from the second fixing part (532b) and abuts against the surface of that side. The adjusting nut (535) is threaded onto the threaded portion of the connecting bolt (534) and is located on the side of the second fixing portion (532b) away from the first fixing portion (531b), and abuts against the surface of that side. A spring (536) is sleeved on the threaded part of the connecting bolt (534). Its two axial ends abut against the side of the first fixing part (531b) facing the second fixing part (532b) and the side of the second fixing part (532b) facing the first fixing part (531b), respectively, and apply an elastic force to the first fixing part (531b) and the second fixing part (532b) to make them move away from each other.

5. The titration apparatus according to claim 2, characterized in that, The drive mechanism (8) includes: The first bearing bracket (81) is fixed on the support plate (12); The second bearing bracket (82) is fixed on the support plate (12) and is arranged parallel to and spaced apart from the first bearing bracket (81); The lead screw (83) is rotatably connected between the first bearing bracket (81) and the second bearing bracket (82); The motor (84) is fixed on the support plate (12) and electrically connected to the control box (9); A reducer (85) is connected to one end of a motor (84) and a lead screw (83); The movable seat (86) is threaded to the circumferential surface of the lead screw (83); The end of the plunger rod (7) away from the buffer liquid pipe (6) is fixedly connected to the movable seat (86), and the buffer liquid pipe (6) is fixed on the second bearing bracket (82); The motor (84) drives the lead screw (83) to rotate, which in turn drives the moving seat (86) to move along the axial direction of the lead screw (83), which in turn drives the plunger rod (7) to move relative to the cylindrical tube (61).

6. The titration apparatus according to claim 5, characterized in that, The drive mechanism (8) also includes a slide rail (87) between the first bearing bracket (81) and the second bearing bracket (82), and the movable seat (86) slides on the slide rail (87).

7. The titration apparatus according to claim 2, characterized in that, It also includes an electromagnetic stirrer (100) placed on the base plate (11), and the reaction flask (3) is placed on the electromagnetic stirrer (100); a stirring magnet (200) is placed inside the reaction flask (3); The electromagnetic stirrer (100) is electrically connected to the control box (9).

8. The titration apparatus according to claim 2, characterized in that, It also includes a color sensor (300) fixed on the base plate (11) or support plate (12), and the color sensor (300) is electrically connected to the control box (9).

9. The titration apparatus according to claim 8, characterized in that, Also includes: A lighting lamp (400) is fixed on a support plate (12) and is electrically connected to a control box (9); The background plate (500) is vertically fixed on the base plate (11); the reaction flask (3) is located between the lighting lamp (400) and the background plate (500).

10. The titration apparatus according to any one of claims 1 to 9, characterized in that, The control box (9) includes: - Controller; - Control panel, which includes a power switch (91), a flow rate adjustment knob (92) and a display screen (93); - A battery, located inside the control box (9), is used to provide power; The controller is electrically connected to the titration control valve (41), the inlet valve (65), the outlet valve (63), and the drive mechanism (8), respectively.

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