A small automatic acid preparation device and acid preparation method

Abstract

The present invention discloses a small automatic acid preparation device and an acid preparation method. The device includes a base plate, a PLC and a plurality of acid preparation units; the PLC is connected to all the acid preparation units; each acid preparation unit includes a transmission mechanism, a liquid suction mechanism and a weighing mechanism; the transmission mechanism is used to send a liquid bottle containing raw acid into the device and send an empty liquid bottle out of the device; the liquid suction mechanism is used to take the raw acid from the liquid bottle through the jet technology and send it into the acid preparation barrel of the weighing mechanism; the weighing mechanism is used to detect the quality of the acid preparation barrel and control the amount of water added. The liquid suction mechanism of the device uses the jet technology to take acid and atomize the raw acid, converting the current liquid-liquid acid preparation into liquid-mist acid preparation, which not only realizes the transfer of the raw acid, but also atomizes the raw acid into small droplets, increases the specific surface area, makes the raw acid contact with the acid liquid or water more fully, greatly improves the heat dissipation effect and heat dissipation efficiency during dilution, and cleverly solves the current heat dissipation problem during acid preparation.

Description

Technical Field

[0001] The invention relates to the field of acid solution preparation, in particular to a small automatic acid preparation device and an acid preparation method. Background Art

[0002] At present, different concentrations of acid, including sulfuric acid, hydrochloric acid, formic acid, etc., are used in various manufacturing industries such as chemical, pharmaceutical, and textile. Because the acid concentration requirements of various industries are different, most of the acid used is prepared by diluting concentrated acid. In the acid preparation process, concentrated acid will release a lot of heat when diluted. How to solve the heat dissipation is a very important issue. If the heat cannot be dissipated in time, the acid will boil due to the rise in temperature, and even splashing will occur, causing great safety hazards.

[0003] The current method of diluting acid is to manually add pure water to the acid preparation barrel first, and then add the original acid and stir. Manual dilution of acid is very dangerous, such as the corrosion of the original acid in contact with the skin, the inhalation hazard of the volatilized acid, and the large amount of heat released when the original acid is mixed with water, which can cause harm to the human body if not handled with care. At present, many automated acid preparation devices are designed for industrial acid with large demand. For laboratory-level acid with smaller demand, not only is the acid addition process complicated and the equipment occupies a large area, but it is also easy to cause waste of resources. Summary of the invention

[0004] In view of the deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a small automatic acid preparation device and an acid preparation method.

[0005] The technical solution of the present invention to solve the technical problem of the device is to provide a small automatic acid dispensing device, characterized in that the device includes a base plate, a PLC and a plurality of acid dispensing units; the PLC is connected to all the acid dispensing units; each acid dispensing unit includes a transmission mechanism, a liquid suction mechanism and a weighing mechanism;

[0006] The conveying mechanism is used to send the liquid bottle containing raw acid into the device and to send the empty liquid bottle out of the device; the liquid suction mechanism is used to take the raw acid out of the liquid bottle by jet technology and send it into the acid preparation barrel of the weighing mechanism; the weighing mechanism is used to detect the quality of the acid preparation barrel and control the amount of water added.

[0007] The liquid suction mechanism includes a stepper motor, a ball screw, a limit switch, a liquid suction tube, a liquid suction rack, a liquid extractor, an air pipe, an acid distribution tube, a one-way valve and a connecting piece; the frame of the ball screw is fixed on the base plate; the stepper motor is arranged on the frame of the ball screw, and the output end of the stepper motor is connected to the ball screw; a plurality of liquid suction tubes are arranged on the liquid suction rack, and the liquid suction rack is fixed on the ball of the ball screw; a limit switch is arranged on the frame of the ball screw, and is located at the origin of the liquid suction rack; one end of each liquid suction tube is connected to its own through a catheter The other end of the liquid extractor can touch the bottom of the respective liquid bottles; each liquid extractor has three interfaces, one is sealedly connected to one end of the respective pipette, one is sealedly connected to one end of the respective liquid distribution pipe, and the other is sealedly connected to one end of the connecting piece; the other end of the connecting piece is sealedly connected to one end of the air pipe; the other end of the air pipe is connected to an external air source; the other end of the liquid distribution pipe extends into the acid distribution barrel of the weighing mechanism; a one-way valve is arranged on the pipette, so that the liquid can only flow from the liquid bottle to the liquid extractor.

[0008] The transmission mechanism includes a moving plate, a DC motor, a photoelectric sensor, a proximity switch, a gear, a rack and a positioning piece; the moving plate can be slidably mounted on the base plate and can slide relative to the base plate; a rack is fixedly mounted on the moving plate; the DC motor is arranged on the base plate or the frame of the ball screw of the liquid suction mechanism, and a gear is fixed on its output end, the gear is meshed with the rack, and the DC motor drives the moving plate to move through the gear and the rack; the photoelectric sensor is arranged on the base plate or the frame of the ball screw, and when a liquid bottle passes through the photoelectric sensor, the photoelectric sensor will be closed once to record the number of liquid bottles; positioning pieces are arranged at both ends of the moving plate; the proximity switch is arranged on the base plate or the frame of the ball screw, and the proximity switch is used to locate the position of the moving plate through the cooperation between the proximity switch and the positioning piece.

[0009] The weighing mechanism includes a weighing sensor, a tray, an acid preparation barrel, a solenoid valve and a water pipe; one end of the water pipe is connected to an external water source, and the other end extends into the acid preparation barrel; a solenoid valve is arranged on the water pipe, and the solenoid valve is used to control the water supply; the acid preparation barrel is arranged on the tray and supported by the tray; a weighing sensor is arranged under the tray, and the weighing sensor is used to weigh the weight of the acid preparation barrel.

[0010] The technical solution of the present invention to solve the technical problem of the method is to provide an acid preparation method based on the small-scale automatic acid preparation device, characterized in that the method comprises the following steps:

[0011] Working condition 1: There is acid in the acid preparation barrel, and the concentration of the acid prepared this time is the same as the acid in the acid preparation barrel;

[0012] (1) Loading: When acid preparation begins, place the liquid bottle containing the original acid on the moving plate; the PLC detects the state of the limit switch; if the limit switch is in the closed state, the liquid pipetting rack is at its origin position and the DC motor starts; if the limit switch is in the open state, the stepper motor starts and drives the liquid pipetting rack to move vertically upward through the ball screw. When the liquid pipetting rack touches the limit switch and causes the limit switch to close, the PLC receives a signal to control the stepper motor to stop. At this time, the liquid pipetting rack is at its origin position and the DC motor starts; the started DC motor drives the moving plate to move horizontally through the gear and rack to send the liquid bottle containing the original acid into the device; when the moving plate moves When the moving plate moves to the position where the positioning piece on it matches the proximity switch, the proximity switch is closed; the PLC receives the signal to control the DC motor to stop moving, and the moving plate stops moving. At this time, the bottle mouths of the liquid bottles are located directly below their respective pipettes; while the moving plate moves, the number of liquid bottles is recorded by the closing times of the photoelectric sensor received by the PLC; when the number of liquid bottles is equal to the set number, step (2) is entered; when the number of liquid bottles is less than the set number, the DC motor is started, and the moving plate is driven to move horizontally through the gear and rack, and the liquid bottles containing raw acid are sent out of the device, and the acid preparation is stopped. After the matching with the set number is completed, the loading process is repeated;

[0013] (2) Add acid: by formula Calculate the number of steps l of the stepper motor, and ensure that the pipette can accurately reach the bottom of the liquid bottle through step control, where s is the distance between the end of the pipette and the bottom of the liquid bottle when the pipette rack is at the origin, a is the subdivision of the stepper motor, and d is the pitch of the ball screw; after the stepper motor drives the pipette rack to move down for l steps, the PLC controls the stepper motor to stop, at which time the end of each pipette touches the bottom of its own liquid bottle; then high-speed cold air is introduced into the air pipe, and the high-speed cold air flows into the liquid collector through the connecting piece, causing the inside of the liquid collector to The atmospheric pressure is lower than that in the liquid bottle, which makes the air pressure at both ends of the pipette unbalanced. The atmospheric pressure presses the original acid from the liquid bottle into the liquid extractor. The original acid is atomized into droplets in the liquid extractor after being impacted by the high-speed airflow. The droplets are then flushed into the acid preparation barrel through the acid preparation pipe. The specific surface area of ​​the atomized droplets becomes larger, and the contact with the acid in the acid preparation barrel is more complete, which greatly improves the heat dissipation efficiency. During the process of adding acid from the liquid bottle to the acid preparation barrel, the PLC monitors the quality of the acid preparation barrel in real time through the weighing sensor. When the quality of the acid preparation barrel does not change, the acid addition process ends.

[0014] (3) Acid preparation: by formula Calculate the amount of water added m, where n is the concentration of the acid in the acid preparation barrel, M is the mass of the original acid, and N is the concentration of the original acid; then the PLC closes the solenoid valve to start adding water, and the weighing sensor monitors the mass of the acid preparation barrel in real time and transmits the mass information to the PLC; when the amount of water added reaches the calculated value m, the PLC disconnects the solenoid valve, stops adding water, and completes the acid preparation;

[0015] Working condition 2: Prepare acid solution of new concentration in an empty acid preparation barrel;

[0016] (1) Loading: When acid preparation begins, place the liquid bottle containing the original acid on the moving plate; the PLC detects the state of the limit switch; if the limit switch is in the closed state, the liquid pipetting rack is at its origin position and the DC motor starts; if the limit switch is in the open state, the stepper motor starts and drives the liquid pipetting rack to move vertically upward through the ball screw. When the liquid pipetting rack touches the limit switch and causes the limit switch to close, the PLC receives a signal to control the stepper motor to stop. At this time, the liquid pipetting rack is at its origin position and the DC motor starts; the started DC motor drives the moving plate to move horizontally through the gear and rack to send the liquid bottle containing the original acid into the device; when the moving plate moves When the moving plate moves to the position where the positioning piece on it matches the proximity switch, the proximity switch is closed; the PLC receives the signal to control the DC motor to stop moving, and the moving plate stops moving. At this time, the bottle mouths of the liquid bottles are located directly below their respective pipettes; while the moving plate moves, the number of liquid bottles is recorded by the closing times of the photoelectric sensor received by the PLC; when the number of liquid bottles is equal to the set number, step (2) is entered; when the number of liquid bottles is less than the set number, the DC motor is started, and the moving plate is driven to move horizontally through the gear and rack, and the liquid bottles containing raw acid are sent out of the device, and the acid preparation is stopped. After the matching with the set number is completed, the loading process is repeated;

[0017] (2) Pre-adding water: According to the concentration of the original acid and the concentration of the new acid to be prepared, the total amount of water to be added is estimated, and then the pre-adding water amount m1 is set according to the estimated total amount of water to be added; the PLC closes the solenoid valve to start adding water, and the weighing sensor monitors the quality of the acid preparation barrel in real time and transmits the quality information to the PLC; when the pre-adding water amount reaches the set value m1, the PLC disconnects the solenoid valve and stops adding water;

[0018] (3) Add acid: by formula Calculate the number of steps l of the stepper motor, and ensure that the pipette can accurately reach the bottom of the liquid bottle through step control, where s is the distance between the end of the pipette and the bottom of the liquid bottle when the pipette rack is at the origin, a is the subdivision of the stepper motor, and d is the pitch of the ball screw; after the stepper motor drives the pipette rack to move down for l steps, the PLC controls the stepper motor to stop, at which time the end of each pipette touches the bottom of its own liquid bottle; then high-speed cold air is introduced into the air pipe, and the high-speed cold air flows into the liquid collector through the connecting piece, causing the inside of the liquid collector to The atmospheric pressure is lower than that in the liquid bottle, which makes the air pressure at both ends of the pipette unbalanced. The atmospheric pressure presses the original acid from the liquid bottle into the liquid extractor. The original acid is atomized into droplets in the liquid extractor after being impacted by the high-speed airflow. The droplets are then flushed into the acid preparation barrel through the acid preparation pipe. The specific surface area of ​​the atomized droplets becomes larger, and the contact with the water in the acid preparation barrel is more complete, which greatly improves the heat dissipation efficiency. During the process of adding acid from the liquid bottle to the acid preparation barrel, the PLC monitors the quality of the acid preparation barrel in real time through the weighing sensor. When the quality of the acid preparation barrel does not change, the acid addition process ends.

[0019] (4) Acid preparation: by formula Calculate the amount of water to be added m2, where n is the concentration of the new acid to be prepared, M is the mass of the original acid, and N is the concentration of the original acid; then the PLC closes the solenoid valve to start adding water, and the weighing sensor monitors the mass of the acid preparation barrel in real time and transmits the quality information to the PLC; when the amount of water added reaches the calculated value m2, the PLC disconnects the solenoid valve, stops adding water, and completes the acid preparation.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] (1) The liquid suction mechanism of the device uses jet technology to take acid and atomize the original acid, converting the current liquid-liquid acid preparation into liquid-mist acid preparation. It not only realizes the transfer of the original acid, but also atomizes the original acid into small droplets, which increases the specific surface area and makes the original acid contact with the acid liquid or water more fully, greatly improving the heat dissipation effect and heat dissipation efficiency during dilution, and cleverly solving the heat dissipation problem during current acid preparation.

[0022] (2) Small droplets are more dispersed than liquids and will not generate heat in a certain area. In addition, the atomized acid droplets have a larger specific surface area and their heat dissipation effect is much stronger than that of liquids. Combined with the high-speed cold air sprayed in, the temperature rise in the acid preparation barrel can be effectively suppressed.

[0023] (3) The liquid dispenser has no moving parts and is made entirely of PVDF material to ensure that it will not be corroded by strong acids.

[0024] (4) A one-way valve is provided on the liquid pipette to ensure that the gas does not rush into the liquid bottle and cause the original acid to splash, so that the original acid can only flow from the liquid bottle to the liquid extractor.

[0025] (5) By controlling all acid preparation units through PLC, it is possible to prepare different types of acids with different concentrations at the same time, thereby improving the acid preparation efficiency.

[0026] (6) A more precise stepper motor is used as the power for moving the pipette. By controlling the number of steps of the stepper motor, the end of the pipette can accurately reach the bottom of the liquid bottle, avoiding the waste of original acid and achieving accurate acid distribution.

[0027] (7) The weighing mechanism converts the measurement of the acid volume into mass measurement, which not only reduces the number of devices inside the acid preparation barrel, but also reduces the difficulty of measurement.

[0028] (8) This device can be used in the laboratory. It is simple to operate, safe and efficient, occupies a small area, and is easy to operate by one person. It not only improves safety, but also greatly ensures the accuracy and efficiency of acid preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of the overall structure of an embodiment of the present invention is shown in the front view;

[0030] Figure 2 It is a right side schematic diagram of the overall structure of an embodiment of the present invention;

[0031] Figure 3 A right side schematic diagram of a transmission mechanism according to an embodiment of the present invention;

[0032] Figure 4 It is a right side schematic diagram of a partial structure of a liquid suction mechanism according to an embodiment of the present invention;

[0033] Figure 5 A right side schematic diagram of a connection structure of a liquid dispenser according to an embodiment of the present invention;

[0034] Figure 6 It is a schematic right view of a weighing mechanism according to an embodiment of the present invention.

[0035] In the figure: 1. conveying mechanism; 2. liquid suction mechanism; 3. weighing mechanism; 4. substrate; 5. liquid container;

[0036] 11. Moving plate; 12. DC motor; 13. Photoelectric sensor; 14. Proximity switch; 15. Gear; 16. Rack; 17. Positioning piece;

[0037] 21. Stepper motor; 22. Ball screw; 23. Limit switch; 24. Pipette; 25. Pipette stand; 26. Liquid extractor; 27. Air pipe; 28. Acid distribution pipe; 29. ​​Check valve; 210. Connecting piece;

[0038] 31. Weighing sensor; 32. Pallet; 33. Acid barrel; 34. Solenoid valve; 35. Water pipe. DETAILED DESCRIPTION

[0039] The present invention is further described below in conjunction with the embodiments and drawings. The specific embodiments are only used to further illustrate the present invention in detail and do not limit the protection scope of the claims of this application.

[0040] The present invention provides a small automatic acid preparation device (hereinafter referred to as the device, see Figure 1-6 ), characterized in that the device comprises a substrate 4, a PLC and a plurality of acid distribution units ( Figure 1 There are 6 acid dispensing units in the system); the PLC is connected to all the acid dispensing units and can control all the acid dispensing units to simultaneously dispense different types of acids of different concentrations; each acid dispensing unit includes a conveying mechanism 1, a liquid suction mechanism 2 and a weighing mechanism 3;

[0041] The conveying mechanism 1 is used to deliver the liquid bottle 5 containing the original acid into the device and to deliver the empty liquid bottle 5 out of the device; the liquid suction mechanism 2 is used to take the original acid out of the liquid bottle 5 and deliver it to the acid preparation barrel 33; the weighing mechanism 3 is used to detect the quality of the acid preparation barrel 33 and control the amount of water added;

[0042] The liquid pipetting mechanism 2 includes a stepper motor 21, a ball screw 22, a limit switch 23, a pipette 24, a pipette frame 25, a liquid extractor 26, an air pipette 27, an acid distribution pipette 28, a one-way valve 29 and a connecting piece 210; the frame of the ball screw 22 is fixed on the substrate 4; the stepper motor 21 is arranged on the frame of the ball screw 22, and the output end thereof is connected to the ball screw 22; a plurality of pipettes 24 are arranged at the same height on the pipette frame 25 (the equal height arrangement means that each pipette 24 is at the same distance from the bottom of its respective liquid bottle 5), the pipette frame 25 is fixed on the ball of the ball screw 22, and the rotational motion of the stepper motor 21 is converted into the vertical motion of the pipette frame 25 and the pipette 24 through the ball screw 22; a limit switch 23 is arranged on the frame of the ball screw 22, and is located at the origin position of the pipette frame 25, and is used to mark the pipette frame 25. The origin position of the liquid rack 25 is the top limit position of the stroke of the liquid pipetting rack 25; one end of each liquid pipette 24 is connected to the respective liquid extractor 26 through a conduit, and the other end can contact the bottom of the respective liquid bottle 5; each liquid extractor 26 has three interfaces, one is sealedly connected to one end of the respective liquid pipette 24, one is sealedly connected to one end of the respective liquid distribution pipe 28, and the other is sealedly connected to one end of the connecting piece 210; the other end of the connecting piece 210 is sealedly connected to one end of the air pipe 27; the other end of the air pipe 27 is connected to an external air source (an air pump in this embodiment); the other end of the liquid distribution pipe 28 extends into the acid distribution barrel 33 of the weighing mechanism 3; a one-way valve 29 is provided on the liquid pipette 24 to ensure that the gas will not rush into the liquid bottle 5 to cause the original acid to splash, so that the liquid can only flow from the liquid bottle 5 to the liquid extractor 26.

[0043] Preferably, the transmission mechanism 1 includes a moving plate 11, a DC motor 12, a photoelectric sensor 13, a proximity switch 14, a gear 15, a rack 16 and a positioning member 17; the moving plate 11 can be slidably mounted on a slide groove or track of the base plate 4 and can slide relative to the base plate 4; a rack 16 is fixedly mounted on one side of the moving plate 11; the DC motor 12 is arranged on the base plate 4 or the frame of the ball screw 22, and a gear 15 is fixed on its output end, the gear 15 is meshed with the rack 16, and the DC motor 12 is connected to the gear 15 and the rack 16. 6 drives the moving plate 11 to move; the photoelectric sensor 13 is arranged on the base plate 4 or the frame of the ball screw 22, and is located above the gear 15. When a liquid bottle 5 passes by the photoelectric sensor 13, the photoelectric sensor 13 will be closed once, thereby recording the number of the liquid bottles 5; both ends of the other side of the moving plate 11 are provided with positioning members 17; the proximity switch 14 is arranged on the base plate 4 or the frame of the ball screw 22, and the proximity switch 14 can locate the position of the moving plate 11 through the cooperation between the proximity switch 14 and the positioning member 17;

[0044] Preferably, the weighing mechanism 3 includes a weighing sensor 31, a tray 32, an acid preparation barrel 33, a solenoid valve 34 and a water pipe 35; one end of the water pipe 35 is connected to an external water source, and the other end extends into the acid preparation barrel 33; a solenoid valve 34 is provided on the water pipe 35, and the solenoid valve 34 is used to control the supply of water; the solenoid valve 34 is fixed on the substrate 4 and is located next to the liquid extractor 26; the acid preparation barrel 33 is arranged on the tray 32 and supported by the tray 32; a weighing sensor 31 is provided under the tray 32, and the weighing sensor 31 is used to weigh the weight of the acid preparation barrel 33.

[0045] Preferably, the PLC is electrically connected to the DC motor 12 , the photoelectric sensor 13 , the proximity switch 14 , the stepper motor 21 , the limit switch 23 , the weighing sensor 31 and the solenoid valve 34 , respectively.

[0046] Preferably, the liquid extractor 26 is made of PVDF.

[0047] Preferably, the one-way valve 29 is a perfluoroether diaphragm one-way valve.

[0048] Preferably, in order to ensure that the weighing sensor 31 can work stably in the acid-making environment for a long time, the entire weighing sensor 31 is wrapped with polytetrafluoroethylene material to prevent corrosion by the original acid.

[0049] The present invention provides an acid dispensing method (hereinafter referred to as the method) based on the small-scale automatic acid dispensing device, characterized in that the method comprises the following steps:

[0050] Working condition 1: There is acid liquid in the acid preparation barrel 33, and the concentration of the acid prepared this time is the same as the concentration of the acid liquid in the acid preparation barrel 33;

[0051] (1) Loading: When acid preparation begins, place the liquid bottle 5 containing the original acid on the moving plate 11; the PLC detects the state of the limit switch 23; if the limit switch 23 is in the closed state, the liquid pipetting rack 25 is at its origin position, and the DC motor 12 starts; if the limit switch 23 is in the open state, the stepper motor 21 starts, and drives the liquid pipetting rack 25 to move vertically upward through the ball screw 22. When the liquid pipetting rack 25 touches the limit switch 23 and causes the limit switch 23 to close, the PLC receives a signal to control the stepper motor 21 to stop. At this time, the liquid pipetting rack 25 is at its origin position, and the DC motor 12 starts; the started DC motor 12 drives the moving plate 11 to move horizontally through the gear 15 and the rack 16, and the liquid pipetting rack 5 containing the original acid is fed into the device; When the moving plate 11 moves to the position where the positioning member 17 thereon cooperates with the proximity switch 14, the proximity switch 14 is closed; the PLC receives a signal to control the DC motor 12 to stop moving, and the moving plate 11 stops moving. At this time, the bottle mouths of the liquid bottles 5 are located directly below their respective pipettes 24; while the moving plate 11 moves, the number of closing times of the photoelectric sensor 13 received by the PLC is used to record the number of liquid bottles 5; when the number of liquid bottles 5 is equal to the set number, step (2) is entered; when the number of liquid bottles 5 is less than the set number, the DC motor 12 is started, and the moving plate 11 is driven to move horizontally through the gear 15 and the rack 16, and the liquid bottles 5 containing raw acid are sent out of the device, and the acid preparation is stopped. After completing the matching with the set number, the loading process is repeated;

[0052] (2) Add acid: by formula The number of steps of the stepper motor 21 is calculated, and the number of steps is controlled to ensure that the pipette 24 can accurately reach the bottom of the liquid bottle 5, where s is the distance between the end of the pipette 24 and the bottom of the liquid bottle 5 when the pipette frame 25 is at the origin, a is the subdivision of the stepper motor 21, and d is the pitch of the ball screw 22; after the stepper motor 21 drives the pipette frame 25 to move downward for 1 step, the PLC controls the stepper motor 21 to stop, and at this time, the end of each pipette 24 contacts the bottom of its own liquid bottle 5; then high-speed cold air is introduced into the air pipe 27, and the high-speed cold air flows into the liquid collector 26 through the connecting piece 210, causing the liquid collector to The atmospheric pressure inside the liquid bottle 26 is lower than the atmospheric pressure inside the liquid bottle 5, so that the air pressure at both ends of the liquid pipette 24 is unbalanced. The atmospheric pressure presses the original acid from the liquid bottle 5 into the liquid extractor 26. The original acid is atomized into droplets in the liquid extractor 26 by the impact of the high-speed airflow. The droplets are then rushed into the acid preparation barrel 33 through the acid preparation pipe 28. The specific surface area of ​​the atomized droplets becomes larger, and the contact with the acid in the acid preparation barrel 33 is more sufficient, which greatly improves the heat dissipation efficiency. During the process of adding acid from the liquid bottle 5 to the acid preparation barrel 33, the PLC monitors the mass of the acid preparation barrel 33 in real time through the weighing sensor 31. When the mass of the acid preparation barrel 33 does not change, the acid addition process ends.

[0053] (3) Acid preparation: by formula The mass of water to be added, i.e., the amount of water added m, is calculated, where n is the concentration of the acid solution in the acid preparation barrel 33, M is the mass of the original acid, and N is the concentration of the original acid; then the PLC closes the solenoid valve 34 to start adding water, and the weighing sensor 31 monitors the mass of the acid preparation barrel 33 in real time and transmits the mass information to the PLC; when the amount of water added reaches the calculated value m, the PLC disconnects the solenoid valve 34, stops adding water, and completes the acid preparation.

[0054] Working condition 2: preparing acid solution of new concentration in the empty acid preparation barrel 33;

[0055] (1) Loading: When acid preparation begins, place the liquid bottle 5 containing the original acid on the moving plate 11; the PLC detects the state of the limit switch 23; if the limit switch 23 is in the closed state, the liquid pipetting rack 25 is at its origin position, and the DC motor 12 starts; if the limit switch 23 is in the open state, the stepper motor 21 starts, and drives the liquid pipetting rack 25 to move vertically upward through the ball screw 22. When the liquid pipetting rack 25 touches the limit switch 23 and causes the limit switch 23 to close, the PLC receives a signal to control the stepper motor 21 to stop. At this time, the liquid pipetting rack 25 is at its origin position, and the DC motor 12 starts; the started DC motor 12 drives the moving plate 11 to move horizontally through the gear 15 and the rack 16, and the liquid pipetting rack 5 containing the original acid is fed into the device; When the moving plate 11 moves to the position where the positioning member 17 thereon cooperates with the proximity switch 14, the proximity switch 14 is closed; the PLC receives a signal to control the DC motor 12 to stop moving, and the moving plate 11 stops moving. At this time, the bottle mouths of the liquid bottles 5 are located directly below their respective pipettes 24; while the moving plate 11 moves, the number of closing times of the photoelectric sensor 13 received by the PLC is used to record the number of liquid bottles 5; when the number of liquid bottles 5 is equal to the set number, step (2) is entered; when the number of liquid bottles 5 is less than the set number, the DC motor 12 is started, and the moving plate 11 is driven to move horizontally through the gear 15 and the rack 16, and the liquid bottles 5 containing raw acid are sent out of the device, and the acid preparation is stopped. After completing the matching with the set number, the loading process is repeated;

[0056] (2) Pre-adding water: According to the concentration of the original acid and the concentration of the new acid to be prepared, the total amount of water to be added is estimated, and then the pre-adding water amount m1 is set according to the estimated total amount of water to be added; the PLC closes the solenoid valve 34 to start adding water, and the weighing sensor 31 monitors the quality of the acid preparation barrel 33 in real time and transmits the quality information to the PLC; when the pre-adding water amount reaches the set value m1, the PLC disconnects the solenoid valve 34 and stops adding water;

[0057] (3) Add acid: by formula The number of steps l of the stepper motor 21 is calculated, and the step control is used to ensure that the pipette 24 can accurately reach the bottom of the liquid bottle 5, where s is the distance between the end of the pipette 24 and the bottom of the liquid bottle 5 when the pipette frame 25 is at the origin, a is the subdivision of the stepper motor 21, and d is the pitch of the ball screw 22; after the stepper motor 21 drives the pipette frame 25 to move downward for l step, the PLC controls the stepper motor 21 to stop, and at this time, the end of each pipette 24 contacts the bottom of its own liquid bottle 5; then high-speed cold air is introduced into the air pipe 27, and the high-speed cold air flows into the liquid collector 26 through the connecting piece 210, resulting in liquid collection. The atmospheric pressure inside the device 26 is lower than the atmospheric pressure inside the liquid bottle 5, so that the air pressure at both ends of the liquid pipette 24 is unbalanced. The atmospheric pressure presses the original acid from the liquid bottle 5 into the liquid extractor 26. The original acid is atomized into droplets in the liquid extractor 26 by the impact of the high-speed airflow. The droplets are then rushed into the acid preparation barrel 33 through the acid preparation pipe 28. The specific surface area of ​​the atomized droplets becomes larger, and the contact with the water in the acid preparation barrel 33 is more sufficient, which greatly improves the heat dissipation efficiency. During the process of adding acid from the liquid bottle 5 to the acid preparation barrel 33, the PLC monitors the mass of the acid preparation barrel 33 in real time through the weighing sensor 31. When the mass of the acid preparation barrel 33 does not change, the acid addition process ends.

[0058] (4) Acid preparation: by formula The mass m2 of water that needs to be added, i.e., the amount of water added, is calculated, where n is the concentration of the new acid to be prepared, M is the mass of the original acid, and N is the concentration of the original acid; then the PLC closes the solenoid valve 34 to start adding water, and the weighing sensor 31 monitors the mass of the acid preparation barrel 33 in real time and transmits the mass information to the PLC; when the amount of water added reaches the calculated value m2, the PLC disconnects the solenoid valve 34, stops adding water, and completes the acid preparation.

[0059] Any matters not described in the present invention are applicable to the prior art.

Claims

1. A small automatic acid preparation device, characterized in that The device includes a base plate, a PLC and several acid dispensing units; the PLC is connected to all the acid dispensing units; each acid dispensing unit includes a transmission mechanism, a liquid suction mechanism and a weighing mechanism; The conveying mechanism is used to send the liquid bottle containing raw acid into the device and to send the empty liquid bottle out of the device; the liquid suction mechanism is used to take the raw acid out of the liquid bottle by jet technology and send it into the acid preparation barrel of the weighing mechanism; the weighing mechanism is used to detect the quality of the acid preparation barrel and control the amount of water added; The liquid suction mechanism includes a stepper motor, a ball screw, a limit switch, a liquid suction tube, a liquid suction rack, a liquid extractor, an air pipe, an acid distribution tube, a one-way valve and a connecting piece; the frame of the ball screw is fixed on the base plate; the stepper motor is arranged on the frame of the ball screw, and the output end of the stepper motor is connected to the ball screw; a plurality of liquid suction tubes are arranged on the liquid suction rack, and the liquid suction rack is fixed on the ball of the ball screw; a limit switch is arranged on the frame of the ball screw, and is located at the origin of the liquid suction rack; one end of each liquid suction tube is connected to its own through a catheter The other end of the liquid extractor can touch the bottom of the respective liquid bottles; each liquid extractor has three interfaces, one of which is sealed and connected to one end of the respective liquid pipette, one is sealed and connected to one end of the respective liquid distribution pipette, and the other is sealed and connected to one end of the connecting piece; the other end of the connecting piece is sealed and connected to one end of the air pipette; the other end of the air pipette is connected to an external air source; the other end of the liquid distribution pipe is extended into the acid distribution barrel of the weighing mechanism; a one-way valve is arranged on the liquid pipette, so that the liquid can only flow from the liquid bottle to the liquid extractor; The transmission mechanism includes a moving plate, a DC motor, a photoelectric sensor, a proximity switch, a gear, a rack and a positioning piece; the moving plate can be slidably mounted on the base plate and can slide relative to the base plate; a rack is fixedly mounted on the moving plate; the DC motor is arranged on the base plate or the frame of the ball screw of the liquid suction mechanism, and a gear is fixed on its output end, the gear is meshed with the rack, and the DC motor drives the moving plate to move through the gear and the rack; the photoelectric sensor is arranged on the base plate or the frame of the ball screw, and when a liquid bottle passes through the photoelectric sensor, the photoelectric sensor will be closed once, and then the number of liquid bottles will be recorded; positioning pieces are arranged at both ends of the moving plate; the proximity switch is arranged on the base plate or the frame of the ball screw, and the proximity switch is used to locate the position of the moving plate through the cooperation of the proximity switch and the positioning piece; The weighing mechanism includes a weighing sensor, a tray, an acid preparation barrel, a solenoid valve and a water pipe; one end of the water pipe is connected to an external water source, and the other end extends into the acid preparation barrel; a solenoid valve is arranged on the water pipe, and the solenoid valve is used to control the water supply; the acid preparation barrel is arranged on the tray and supported by the tray; a weighing sensor is arranged under the tray, and the weighing sensor is used to weigh the weight of the acid preparation barrel.

2. The small automatic acid preparation device according to claim 1 is characterized in that A plurality of pipettes are arranged at the same height on the pipette rack so that each pipette is at the same distance from the bottom of its respective liquid-containing bottle.

3. The small automatic acid preparation device according to claim 1 is characterized in that The PLC is electrically connected to the DC motor of the transmission mechanism, the photoelectric sensor of the transmission mechanism, the proximity switch of the transmission mechanism, the stepping motor of the suction mechanism, the limit switch of the suction mechanism, the weighing sensor of the weighing mechanism and the solenoid valve of the weighing mechanism.

4. An acid preparation method based on the small automatic acid preparation device according to any one of claims 1 to 3, characterized in that The method comprises the following steps: Working condition 1: There is acid in the acid preparation barrel, and the concentration of the acid prepared this time is the same as the acid in the acid preparation barrel; (1) Loading: When acid preparation begins, place the liquid bottle containing the original acid on the moving plate; the PLC detects the state of the limit switch; if the limit switch is in the closed state, the liquid pipetting rack is at its origin position and the DC motor starts; if the limit switch is in the open state, the stepper motor starts and drives the liquid pipetting rack to move vertically upward through the ball screw. When the liquid pipetting rack touches the limit switch and causes the limit switch to close, the PLC receives a signal to control the stepper motor to stop. At this time, the liquid pipetting rack is at its origin position and the DC motor starts; the started DC motor drives the moving plate to move horizontally through the gear and rack to send the liquid bottle containing the original acid into the device; when the moving plate moves When the moving plate moves to the position where the positioning piece on it matches the proximity switch, the proximity switch is closed; the PLC receives the signal to control the DC motor to stop moving, and the moving plate stops moving. At this time, the bottle mouths of the liquid bottles are located directly below their respective pipettes; while the moving plate moves, the number of liquid bottles is recorded by the closing times of the photoelectric sensor received by the PLC; when the number of liquid bottles is equal to the set number, step (2) is entered; when the number of liquid bottles is less than the set number, the DC motor is started, and the moving plate is driven to move horizontally through the gear and rack, and the liquid bottles containing raw acid are sent out of the device, and the acid preparation is stopped. After the matching with the set number is completed, the loading process is repeated; (2) Add acid: by formula Calculate the number of steps of the stepper motor l1, and ensure that the pipette can accurately reach the bottom of the liquid bottle through step control, where s is the distance between the end of the pipette and the bottom of the liquid bottle when the pipette rack is at the origin, a is the subdivision of the stepper motor, and d is the pitch of the ball screw; after the stepper motor drives the pipette rack to move downward for l1 steps, the PLC controls the stepper motor to stop, at which time the end of each pipette touches the bottom of its own liquid bottle; then high-speed cold air is introduced into the air pipe, and the high-speed cold air flows into the liquid collector through the connecting piece, causing the liquid collector to The internal air pressure is lower than the air pressure in the liquid bottle, which makes the air pressure at both ends of the pipette unbalanced. The air pressure presses the original acid from the liquid bottle into the liquid extractor. The original acid is atomized into droplets in the liquid extractor after being impacted by the high-speed airflow. The droplets are then rushed into the acid preparation barrel through the acid preparation pipe. The specific surface area of ​​the atomized droplets becomes larger, and the contact with the acid in the acid preparation barrel is more complete, which greatly improves the heat dissipation efficiency. During the process of adding acid from the liquid bottle to the acid preparation barrel, the PLC monitors the quality of the acid preparation barrel in real time through the weighing sensor. When the quality of the acid preparation barrel does not change, the acid addition process ends. (3) Acid preparation: by formula Calculate the amount of water added m, where n1 is the concentration of the acid in the acid preparation barrel, M is the mass of the original acid, and N is the concentration of the original acid; then the PLC closes the solenoid valve to start adding water, and the weighing sensor monitors the mass of the acid preparation barrel in real time and transmits the mass information to the PLC; when the amount of water added reaches the calculated value m, the PLC disconnects the solenoid valve, stops adding water, and completes the acid preparation; Working condition 2: Prepare acid solution of new concentration in an empty acid preparation barrel; (1) Loading: When acid preparation begins, place the liquid bottle containing the original acid on the moving plate; the PLC detects the state of the limit switch; if the limit switch is in the closed state, the liquid pipetting rack is at its origin position and the DC motor starts; if the limit switch is in the open state, the stepper motor starts and drives the liquid pipetting rack to move vertically upward through the ball screw. When the liquid pipetting rack touches the limit switch and causes the limit switch to close, the PLC receives a signal to control the stepper motor to stop. At this time, the liquid pipetting rack is at its origin position and the DC motor starts; the started DC motor drives the moving plate to move horizontally through the gear and rack to send the liquid bottle containing the original acid into the device; when the moving plate moves When the moving plate moves to the position where the positioning piece on it matches the proximity switch, the proximity switch is closed; the PLC receives the signal to control the DC motor to stop moving, and the moving plate stops moving. At this time, the bottle mouths of the liquid bottles are located directly below their respective pipettes; while the moving plate moves, the number of liquid bottles is recorded by the closing times of the photoelectric sensor received by the PLC; when the number of liquid bottles is equal to the set number, step (2) is entered; when the number of liquid bottles is less than the set number, the DC motor is started, and the moving plate is driven to move horizontally through the gear and rack, and the liquid bottles containing raw acid are sent out of the device, and the acid preparation is stopped. After the matching with the set number is completed, the loading process is repeated; (2) Pre-adding water: According to the concentration of the original acid and the concentration of the new acid to be prepared, the total amount of water to be added is estimated, and then the pre-adding water amount m1 is set according to the estimated total amount of water to be added; the PLC closes the solenoid valve to start adding water, and the weighing sensor monitors the quality of the acid preparation barrel in real time and transmits the quality information to the PLC; when the pre-adding water amount reaches the set value m1, the PLC disconnects the solenoid valve and stops adding water; (3) Add acid: by formula Calculate the number of steps of the stepper motor l2, and ensure that the pipette can accurately reach the bottom of the liquid bottle through step control, where s is the distance between the end of the pipette and the bottom of the liquid bottle when the pipette rack is at the origin, a is the subdivision of the stepper motor, and d is the pitch of the ball screw; after the stepper motor drives the pipette rack to move downward for l2 steps, the PLC controls the stepper motor to stop, at which time the end of each pipette touches the bottom of its own liquid bottle; then high-speed cold air is introduced into the air pipe, and the high-speed cold air flows into the liquid collector through the connecting piece, resulting in liquid collection. The air pressure inside the device is lower than the air pressure in the liquid bottle, which makes the air pressure at both ends of the liquid pipette unbalanced. The air pressure presses the original acid from the liquid bottle into the liquid extractor. The original acid is atomized into droplets in the liquid extractor after being impacted by the high-speed airflow. The droplets are then rushed into the acid preparation barrel through the acid preparation pipe. The specific surface area of ​​the atomized droplets becomes larger, and the contact with the water in the acid preparation barrel is more complete, which greatly improves the heat dissipation efficiency. During the process of adding acid from the liquid bottle to the acid preparation barrel, the PLC monitors the quality of the acid preparation barrel in real time through the weighing sensor. When the quality of the acid preparation barrel does not change, the acid addition process ends. (4) Acid preparation: by formula Calculate the amount of water to be added m2, where n2 is the concentration of the new acid to be prepared, M is the mass of the original acid, and N is the concentration of the original acid; then the PLC closes the solenoid valve to start adding water, and the weighing sensor monitors the mass of the acid preparation barrel in real time and transmits the quality information to the PLC; when the amount of water added reaches the calculated value m2, the PLC disconnects the solenoid valve, stops adding water, and completes the acid preparation.

Images