CN105806994B - Automatic potentiometric titrator - Google Patents

Abstract

The invention provides an automatic potentiometric titrator, comprising a controller, a titrator and a titration area. The outer surface of the titrator is provided with an electrical connection line, the controller is installed on the electrical connection line, a fixing rod is provided at the rear end of the titrator, a fixing head is installed above the fixing rod, a solenoid valve is connected to the right end of the fixing head, a burette is installed on the solenoid valve, an electrode fixing frame is connected to the right end of the solenoid valve, an indicator electrode and a reference electrode are welded below the electrode fixing frame, the burette, the indicator electrode and the reference electrode are arranged above the titration area, and the titration area is arranged on the upper surface of the titrator. The invention has the following beneficial effects: a user only needs to place a solution to be tested in a specific bottle and then place it above the titration area, the titrator can automatically start titration, and can automatically close when the titration is completed, thereby saving manpower and power resources, having an ingenious design, improving market competitiveness, and achieving the purpose of simple structure and reasonable design.

Description

An automatic potentiometric titrator

technical field

The invention is an automatic potentiometric titrator, which belongs to the field of chemical equipment.

Background technique

The determination of the electrode potential is realized by measuring the electromotive force of the primary battery composed of the electrode to be tested and the reference electrode. Therefore, the potentiometric measuring instrument uses a reference electrode, an indicating electrode, and a measuring instrument to form a loop to measure the electrode potential. There are two types of potentiometric measuring instruments: direct potentiometric measuring instruments and potentiometric titration measuring instruments.

Direct potentiometric instruments include a pH meter that uses a pH glass electrode as the indicator electrode to determine the acidity and an ion meter that uses an ion-selective electrode as the indicator electrode to measure the concentration of various ions. Because many electrodes have high resistance, both pH meter and ion meter require high input impedance, and have automatic temperature measurement and compensation functions. After simple calibration, this instrument can directly give acidity or ion concentration.

In the prior art, when the staff needs to use the automatic potentiometric titrator, they need to place the solution to be tested in a specific bottle, then place it above the automatic potentiometric titrator, then plug in the power supply, and then turn on the switch to measure. Very troublesome, not easy to promote.

Contents of the invention

Aiming at the deficiencies in the prior art, the purpose of the present invention is to provide an automatic potentiometric titrator to solve the problems raised in the above-mentioned background technology. The present invention is easy to use, easy to operate, good in stability and high in reliability.

In order to achieve the above object, the present invention is achieved through the following technical solutions: an automatic potentiometric titrator, including a controller, a titrator and a titration area, the outer surface of the titrator is provided with electrical connection wires, the control The controller is installed on the electrical connection line, and the inside of the controller is provided with a printed circuit board and a DC-DC power supply module, and the printed circuit board is welded with a single-chip microcomputer, a memory, a digital/analog converter and a relay, The single-chip microcomputer is connected to the data of the digital/analog converter, and the digital/analog converter is electrically connected to the relay. The rear end of the titrator is provided with a fixed rod, and the fixed head is installed above the fixed rod. The right end of the fixed head is connected with a solenoid valve, and the burette is installed on the solenoid valve. The right end of the solenoid valve is connected with an electrode holder, and an indicating electrode and a reference electrode are welded below the electrode holder. The burette, The indicating electrode and the reference electrode are arranged above the titration area, and the titration area is arranged on the upper surface of the titrator, and a load cell is installed inside the titration area, and a switch and a switch are arranged on the front side of the upper surface of the titrator. indicator light, the inside of the titrator is provided with a modulating amplifier, the modulating amplifier is electrically connected to the indicating electrode and the reference electrode, and the modulating amplifier is electrically connected to the potential comparator through a sampling loop, and the potential comparator is electrically connected to the The potential-time converter is electrically connected, and the potential-time converter is electrically connected with the solenoid valve through a delay circuit.

Further, the electrical connection line runs through the controller and is connected to an external circuit, the electrical connection line realizes the power supply to the titrator through the external circuit, and the relay inside the controller controls the electrical connection line to flow through the titration The current on and off of the instrument then controls the working state of the titrator.

Further, the DC-DC power supply module is electrically connected with the single-chip microcomputer, storage and digital/analog converter, and the DC-DC power supply module is used for power supply when the single-chip microcomputer, storage and digital/analog converter work.

Further, the burette runs through the solenoid valve to the top of the titration area, and a titration bottle is connected to the top of the burette, and a titration solution is placed in the titration bottle.

Further, the load cell is a capacitive load cell, and the load cell is connected to the single-chip microcomputer welded on the printed circuit board through a data line, and the load cell is used to sense the weight above the titration area information and transfer it to the microcontroller.

Further, the potential comparator internally stores a set potential value, and the potential comparator is used to compare the set potential value with the potential signal taken out by the sampling loop, and then send the difference to the potential-time converter as a control signal.

Beneficial effects of the present invention: for an automatic potentiometric titrator of the present invention, the user only needs to place the solution to be tested in a specific bottle, and then place it above the titration area, the titrator can automatically start titration, It can be automatically closed when the time is off, saving manpower and power resources, and the design is ingenious, which improves the market competitiveness and achieves the purpose of simple structure and reasonable design.

Description of drawings

Other characteristics, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

Fig. 1 is the structural representation of a kind of automatic potentiometric titrator of the present invention;

Fig. 2 is the printed circuit board structural representation of a kind of automatic potentiometric titrator of the present invention;

Fig. 3 is the measuring principle block diagram of a kind of automatic potentiometric titrator of the present invention;

Fig. 4 is a switch control principle block diagram of a kind of automatic potentiometric titrator of the present invention;

In the figure: 1-Electrical connection line, 2-Controller, 3-Titrator, 4-Fixed rod, 5-Fixed head, 6-Burette, 7-Electrode holder, 8-Indicating electrode, 9-Reference electrode , 10-titration area, 11-switch, 12-indicator, 13-single chip, 14-storage, 15-digital/analog converter, 16-relay, 17-adjusting amplifier, 18-sampling circuit, 19-point Comparator, 20-potential-time converter, 21-delay circuit, 22-solenoid valve, 23-printed circuit board, 24-load sensor.

detailed description

In order to make the technical means, creative features, goals and effects achieved by the present invention easy to understand, the present invention will be further described below in conjunction with specific embodiments.

Please refer to Fig. 1, Fig. 2, Fig. 3 and Fig. 4, the present invention provides a kind of technical scheme: a kind of automatic potentiometric titrator, comprises controller 2, titrator 3 and titration area 10, and the outer surface of titrator 3 is provided with The electrical connection line 1, the controller 2 is installed on the electrical connection line 1, the inside of the controller 2 is provided with a printed circuit board 23 and a DC-DC power supply module, and the printed circuit board 23 is welded with a single chip microcomputer 13, a memory 14. D/A converter 15 and relay 16, single-chip microcomputer 13 is connected with D/A converter 15 data, D/A converter 15 is electrically connected with relay 16, the rear end of titrator 3 is provided with fixed rod 4, fixed The head 5 is installed above the fixed rod 4, the right end of the fixed head 5 is connected with a solenoid valve 22, the burette 6 is installed on the solenoid valve 22, the right end of the solenoid valve 22 is connected with an electrode holder 7, and the electrode holder 7 is welded below Indicating electrode 8 and reference electrode 9, burette 6, indicating electrode 8 and reference electrode 9 are arranged on the top of titration area 10, and titration area 10 is arranged on the upper surface of titrator 3, and the inside of titration area 10 is equipped with weighing sensor 24. The front side of the upper surface of the titrator 3 is provided with a switch 11 and an indicator light 12. The inside of the titrator 3 is provided with a modulation amplifier 17. The modulation amplifier 17 is electrically connected to the indicator electrode 8 and the reference electrode 9. The modulation amplifier 17 passes through The sampling loop 18 is electrically connected to the potential comparator 19 , the potential comparator 19 is electrically connected to the potential-time converter 20 , and the potential-time converter 20 is electrically connected to the solenoid valve 22 through the delay circuit 21 .

The electrical connection line 1 runs through the controller 2 and is connected to the external circuit. The electrical connection line 1 realizes the power supply to the titrator 3 through the external circuit. The relay 16 inside the controller 2 controls the flow of the electrical connection line 1 through the titrator 3 The current on and off of the titrator then controls the working state of the titrator 3 .

The DC-DC power supply module is electrically connected with the single-chip microcomputer 13, the storage 14 and the digital/analog converter 15, and the DC-DC power supply module is used for power supply when the single-chip microcomputer 13, the storage 14 and the digital/analog converter 15 work.

The burette 6 runs through the solenoid valve 22 to the top of the titration area 10, and the top of the burette 6 is connected with a titration bottle, and a titration solution is placed in the titration bottle.

The load cell 24 is a capacitive load cell 24, the load cell 24 is connected with the single-chip microcomputer 13 welded on the printed circuit board 23 through a data line (not shown in the figure), and the load cell 24 is used for sensing titration The weight information above the area 10 is transmitted to the single-chip microcomputer 13.

The potential comparator 19 internally stores a set potential value, which is Eo, and the potential comparator 19 is used to compare the set potential value with the potential signal taken out by the sampling circuit 18, and then send the difference to the potential- Time converter 20 as control signal

As an embodiment of the present invention: before actual use, the staff can input a critical value of weight into the storage 14, and in actual use, the solution to be tested is placed in a specific bottle, and then placed in the Above the titration area 10, the weighing sensor 24 can detect the weight information above the titration area 10 and transmit it to the single-chip microcomputer 13. After further calculation and processing, the single-chip microcomputer 13 compares it with the weight critical value stored in the memory 14. , if it is higher than this critical value, then the single-chip microcomputer 13 sends a control command to control the relay 16 through the digital/analog converter 15, and then controls the on-off of the external circuit flowing through the titrator 3 current, thereby controlling the titrator 3 to work. At this time, the titration process In the process, the measured ion concentration is converted into an electrical signal by the indicator electrode 8 and the reference electrode 9, and after being amplified by the modulation amplifier 17, the potential signal is taken out by the sampling circuit 18 and compared with the set potential value Eo. The difference △E is sent to the potential-time converter 20 as a control signal. The potential-time converter 20 is a pulse voltage generator, and its function is to generate pulse voltages in two states, on and off. When △E>0 , the potential-time converter 20 outputs a pulse voltage that is applied to both ends of the solenoid valve 22 coil. The solenoid valve 22 is opened, and the titration is carried out normally. When △E=0, the solenoid valve 22 is automatically closed. The function of the delay circuit 21 is that when the titration reaches the end point, the solenoid valve 22 is closed, but it does not sell itself immediately, but prolongs a certain period of time, such as 10s. During this period, if the potential of the solution returns, so that △E>o, Electromagnetic valve 22 can also be automatically opened to add titrant. After l0s, even if there is potential return phenomenon, the solenoid valve 22 is no longer opened.

The basic principles and main features of the present invention and the advantages of the present invention have been shown and described above. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and without departing from the spirit or fundamentals of the present invention. The present invention can be implemented in other specific forms without any specific features. Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in the present invention. Any reference sign in a claim should not be construed as limiting the claim concerned.

In addition, it should be understood that although this specification is described according to implementation modes, not each implementation mode only contains an independent technical solution, and this description in the specification is only for clarity, and those skilled in the art should take the specification as a whole , the technical solutions in the various embodiments can also be properly combined to form other implementations that can be understood by those skilled in the art.

Claims (5)

1. a kind of automatical potentiometric titrimeter, including controller, titrator and titration area, it is characterised in that：The titrator Outer surface is provided with electric connection line, the controller, which is arranged on, to be electrically connected with line, and the controller is internally provided with print Be welded with circuit board processed and DC-DC power module, the printed circuit board single-chip microcomputer, holder, D/A converter and after Electrical equipment, the single-chip microcomputer and D/A converter data cube computation, the D/A converter are electrically connected with relay, the titration The rear end of instrument is provided with fix bar, and gland is arranged on the top of the fix bar, and the right-hand member of the gland is connected with electromagnetism Valve, buret is arranged on the magnetic valve, and the right-hand member of the magnetic valve is connected with electrode fixed mount, the electrode fixed mount Lower section is welded with indicator electrode and reference electrode, and the buret, indicator electrode and reference electrode are arranged on the top in titration area, The titration area is arranged on the upper surface of titrator, and the inside in the titration area is provided with weighing sensor, the weighing and sensing Device is a kind of capacitance weighing sensor, single-chip microcomputer of the weighing sensor by data wire with welding on a printed circuit board Connection, the weighing sensor is used for the weight information perceived above titration area and transmitted into single-chip microcomputer, the titrator It is provided with switch and indicator lamp on front side of upper surface, the titrator is internally provided with modulated amplifier, the modulated amplifier It is electrically connected with indicator electrode and reference electrode, the modulated amplifier is electrically connected with by sampling loop and potential comparator, The potential comparator is electrically connected with current potential-time converter, and the current potential-time converter passes through delay circuit and electromagnetism Valve is electrically connected with.

2. a kind of automatical potentiometric titrimeter according to claim 1, it is characterised in that：The electric connection line is through control Device is connected with external circuit, described to be electrically connected with line by external circuit realization to the power supply of titrator, the controller Internal relay is by controlling the current switching that electric connection line flows through titrator then to control the working condition of titrator.

3. a kind of automatical potentiometric titrimeter according to claim 1, it is characterised in that：The DC-DC power module and list Piece machine, holder and D/A converter are electrically connected with, and the DC-DC power module turns for single-chip microcomputer, holder and D/A Power supply when parallel operation works.

4. a kind of automatical potentiometric titrimeter according to claim 1, it is characterised in that：The buret runs through magnetic valve extremely Titrate to be connected with titration bottle, the titration bottle at the top of the top in area, the buret and be placed with volumetric soiutions.

5. a kind of automatical potentiometric titrimeter according to claim 1, it is characterised in that：The potential comparator internal reservoir There is the potential value of setting, the potential comparator is used to the potential value of this setting taking out electric potential signal ratio with sampling loop Compared with its difference then is sent into current potential-time converter and is used as control signal.