A precise weighing device for chemical powder

Abstract

The present invention discloses a precise weighing device for chemical powders, comprising a weighing mechanism and a dropping mechanism arranged above the weighing mechanism, wherein the dropping mechanism comprises a hopper, a stirring assembly and a powder dropping assembly, wherein the stirring assembly is installed in the hopper, and the powder dropping assembly is installed at the discharge port of the hopper; the powder dropping assembly comprises a supporting structure, a screw motor, a valve plate and a compression spring, wherein the supporting structure is installed at the bottom end of the discharge port of the hopper, the valve plate is installed at the discharge port of the hopper, and the valve plate and the output shaft of the screw motor are connected by a transmission member; the compression spring is arranged between the bottom of the valve plate and the supporting structure. The high-precision automatic powder weighing device of the present invention has less manual intervention, high weighing efficiency, accurate weighing precision, and can pre-compile a weighing program, and can perform batch automatic weighing without manual intervention.

Description

Technical Field

[0001] The invention relates to a powder weighing device, in particular to a chemical powder accurate weighing device. Background Art

[0002] Precision weighing of powders is widely used in the fields of thermal battery production, LED manufacturing, gunpowder preparation, etc. High-precision automatic weighing technology is of great significance to improving product production efficiency, reducing production costs, saving human resources and improving product quality. There are several problems in the current powder weighing production: (i) It is mainly based on manual weighing, with a low degree of automation, and is a labor-intensive job; (ii) It requires high proficiency of operators, high production costs of enterprises, and low production efficiency; (iii) The production raw materials are mainly powder or granular chemical products with a diameter of no more than 10nm, which are easily adsorbed by the human body and cause damage to health; (iv) Due to the high viscosity of some powders, the sticky powder will only fall under the action of gravity when the physical force of adhesion is overcome. Due to the uncertainty of physical adhesion, the amount of material dropped each time is inconsistent, resulting in a large drop deviation. Summary of the invention

[0003] In view of the shortcomings of powder weighing equipment in the prior art, such as low degree of automation and inability to achieve high-precision control of powder, the problem to be solved by the present invention is to provide a precise chemical powder weighing device with less manual intervention, high weighing efficiency and accurate weighing accuracy.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] The present invention provides a precise weighing device for chemical powders, comprising a weighing mechanism and a dropping mechanism arranged above the weighing mechanism, wherein the dropping mechanism comprises a hopper, a stirring assembly and a powder dropping assembly, wherein the stirring assembly is installed in the hopper, and the powder dropping assembly is installed at the discharge port of the hopper; the powder dropping assembly comprises a supporting structure, a screw motor, a valve plate and a compression spring, wherein the supporting structure is installed at the bottom end of the discharge port of the hopper, the valve plate is installed at the discharge port of the hopper, and the valve plate is connected to the output shaft of the screw motor through a transmission member; the compression spring is arranged between the bottom of the valve plate and the supporting structure.

[0006] The transmission component includes a linear guide rail, a lead screw, a nut and a drag plate, wherein the lead screw is connected to the output shaft of the lead screw motor, the nut is meshed and driven with the lead screw, the drag plate is fixedly connected to the nut, and the drag plate is also fixedly connected to the valve plate.

[0007] It also has a linear guide rail, which is horizontally arranged in the axial direction and fixedly installed on the overall frame of the weighing device in a side-standing form, and the carriage is slidably connected to the linear guide rail through a slider;

[0008] The stirring assembly includes a stirring motor, stirring wings, a Y-shaped cage stirring head and a flexible material brush, wherein the output shaft of the stirring motor is coaxially fixedly connected to the connecting rod 3, the bottom end of the connecting rod is connected to the Y-shaped cage stirring head, and the stirring wings are fixedly connected to the connecting rod with screws; the flexible material brush is fixedly connected to the side wall of the connecting rod through a connecting piece, and the brush surface of the flexible material brush is in contact with the inner wall of the hopper.

[0009] The supporting structure is a plate-shaped structural member, compression springs are respectively installed on both sides of the bottom of the structural member, and the hopper is installed in the main frame.

[0010] The present invention has the following beneficial effects and advantages:

[0011] 1. The high-precision automatic powder weighing device of the present invention has less manual intervention, high weighing efficiency, accurate weighing precision, and can pre-compile weighing programs, and can perform batch automatic weighing without manual intervention.

[0012] 2. The weighing controller of the present invention adopts a closed-loop control strategy, maintains real-time communication with equipment such as the screw motor, weighing sensor and stirring motor, obtains the weight data measured by the sensor in real time, and performs precision control by controlling the start and stop of the powder feeding mechanism and the opening size under low latency conditions, thereby ensuring the efficiency and accuracy of weighing.

[0013] 3. The frame of the present invention adopts a windproof design as a whole to prevent air flow from interfering with the weighing result; a Y-shaped cage stirring head is installed at the end of the connecting rod to prevent the powder from sticking and ensure that the powder falls smoothly; the weighing controller is electrically connected to the weighing sensor through the RS232 interface, and the weighing controller can be electrically connected to the industrial control computer through RS232, RS485, CAN or Ethernet.

[0014] 4. The powder dropping component of the present invention can be used for fast and accurate feeding by adjusting the opening size; the weighing sensor feeds back the current material dropping weight data to the control system online in real time; the weighing controller adopts closed-loop control, and controls the start and stop of the powder dropping component by reading the feedback information of the material dropping weight data; the stirring component is used to improve the fluidity of the powder in the hopper; the powder dropping equipment frees workers from the pure manual operation environment, improves production efficiency, saves human resources, and also avoids the adverse effects of dust particles on human health. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the structure of the high-precision automatic powder weighing device of the present invention;

[0016] Figure 2 for Figure 1 Schematic diagram of K-direction structure;

[0017] Figure 3 for Figure 1 Schematic diagram of the cross-sectional structure along line AA;

[0018] Figure 4 Schematic diagram of the hopper discharge port structure.

[0019] Among them, 1 is the main frame, 2 is the stirring wing, 3 is the connecting rod, 4 is the stirring motor, 5 is the linear guide rail, 6 is the Y-shaped cage stirring head, 7 is the hopper, 8 is the flexible material brush, 9 is the frame, 10 is the weighing platform, 11 is the valve plate, 12 is the charging cup, 13 is the infrared sensor, 14 is the compression spring, 15 is the screw motor, 16 is the supporting structure, 17 is the screw, 18 is the nut, and 19 is the drag plate. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the accompanying drawings.

[0021] like Figures 1-2 As shown, the present invention provides a precise weighing device for chemical powders, including a weighing mechanism and a feeding mechanism arranged above the weighing mechanism, the feeding mechanism includes a hopper 7, a stirring assembly and a powder feeding assembly, wherein the stirring assembly is installed in the hopper 7, and the powder feeding assembly is installed at the discharge port of the hopper 7; the powder feeding assembly includes a supporting structure 16, a screw motor 15, a valve plate 11 and a compression spring 14, wherein the supporting structure 16 is installed at the bottom end of the discharge port of the hopper 7, the valve plate 11 is installed at the discharge port of the hopper 7, and the valve plate 11 is connected to the output shaft of the screw motor 15 through a transmission member; the compression spring 14 is arranged between the bottom of the valve plate 11 and the supporting structure.

[0022] like Figure 3 As shown, the transmission parts include a linear guide rail 5, a lead screw 17, a nut 18 and a drag plate 19, wherein the lead screw 17 is connected to the output shaft of the lead screw motor 15, the nut 18 is meshingly connected to the lead screw 17, the drag plate 19 is fixedly connected to the nut 18, and the drag plate 19 is also fixedly connected to the valve plate 11.

[0023] The present invention is equipped with a linear guide rail 5, which is horizontally arranged in the axial direction and fixedly installed on the inner side of the main frame 1 of the weighing device in a side-standing form, and the carriage 19 is slidably connected to the linear guide rail 5 through a slider;

[0024] like Figures 1-2 As shown, in this embodiment, the stirring assembly includes a stirring motor 4, stirring wings 2, a Y-shaped cage stirring head 6 and a flexible material brush 8, wherein the output shaft of the stirring motor 4 is coaxially fixedly connected to the connecting rod 3, the bottom end of the connecting rod 3 is connected to the Y-shaped cage stirring head 6, and the stirring wings 2 are fixedly connected to the connecting rod 3 by screws; the flexible material brush 8 is fixedly connected to the side wall of the connecting rod 3 through a connecting member, and the brush surface of the flexible material brush 8 contacts the inner wall of the hopper 7. The support structure 16 is a plate-like structural member, and compression springs 14 are installed on both sides of the bottom of the structural member, and the hopper 7 is installed in the main frame 1.

[0025] The chemical powder accurate weighing device of the present invention has a feedback control system, including a weighing sensor, a weighing controller, an infrared sensor 13 and an industrial computer; the weighing controller is connected to the weighing sensor for communication via an RS232 interface, the weighing controller can be connected to the industrial computer via an RS232, RS448, CAN or Ethernet interface, and the infrared sensor 13 is connected to the input end of the industrial computer.

[0026] The hopper 7 of the weighing mechanism is used to place the powder to be weighed. The stirring motor 4 drives the flexible material brush 8 and the Y-shaped cage stirring head 6 to rotate, so as to loosen the powder and make it fall smoothly. The stirring motor 4 also drives the flexible material brush 8 to rotate close to the side wall of the hopper to prevent the powder from sticking. Figure 4 As shown, the distance between the outer wall of the Y-shaped cage stirring head 6 and the inner wall of the discharge port of the hopper 4 is x1, the horizontal distance between the edge of the lower discharge port of the valve plate 11 and the inner wall of the discharge port of the hopper 7 is x2, and the distance between the lower end face of the Y-shaped cage stirring head 6 and the valve plate 11 is y1. The design ensures that x1 and y1 are small values. During the working process, the stirring motor 4 drives the Y-shaped cage stirring head 6 to rotate, which can effectively avoid the physical adhesion of the powder on the side wall of the discharge port of the hopper 7 and above the valve plate 11, so that the powder always remains in a smooth state. The stirring head adopts a Y-shaped cage structure, which can make the powder above the discharge port of the hopper 7 replenished in time. When the weighing process is about to end, it is necessary to control the horizontal distance x2 between the edge of the discharge port of the valve plate 11 and the inner wall of the discharge port of the hopper 7 to a very small value, and use the Y-shaped cage stirring head 6 to sweep across the tiny discharge port to accurately control the discharge speed. Because the Y-shaped cage stirring head 6 is projected in a Y shape, the interval angle between two adjacent sweeps across the discharge channel is 120°. Through a reasonable stirring speed, the powder can fall accurately and smoothly at the end of the weighing. The split structure design is adopted between the Y-shaped cage stirring head 6 and the stirring motor 4, which is convenient for installation, disassembly, cleaning and height adjustment. The overall frame of the equipment is mainly composed of a frame 9 as a weighing device and a steel structure 1 located on the frame 9 for fixing components such as the hopper 7 and the stirring motor 4. In the compact structural design, each component can be quickly separated, making the equipment highly maintainable.

[0027] The valve plate 11 of the powder dropping mechanism is preloaded by the compression spring 14 below, and the valve plate 11 is preloaded by the compression spring 14, so that the valve plate 11 is tightly pressed against the lower end surface of the discharge port of the hopper 7. This structural design can automatically compensate for the gap or deviation between the valve plate 11 and the discharge port of the hopper 7 due to wear, ensure good sealing, effectively avoid powder residue, and avoid mixing between different batches of powder. The drive component of the valve plate 11 uses a screw motor to ensure that the change of the valve plate opening is controlled at the micron level, thereby ensuring the weighing accuracy.

[0028] The feedback control system controls the stirring speed of the hopper and the leakage speed of the leakage actuator according to the remaining weight to be weighed. After the measurement is completed, it can be uploaded to the industrial computer via RS232, RS485, CAN or Ethernet, and the weighing results are statistically processed. By using a touch screen industrial computer, it is convenient for touch operation, and through visual programming, specific powder weighing values, weighing process and other parameters can be quickly set, and the current weighing status can be obtained in real time. The weighing platform 10 is used to carry the weighing sensor and perform horizontal and height adjustments. The infrared sensor 13 installed on the weighing platform 10 automatically starts the powder weighing program after sensing the charging cup 12. The weighing platform 10 is equipped with a weighing sensor with communication function, which is used to feedback the current weight data to the weighing controller online in real time.

[0029] The flexible brush 8, stirring wing 2, Y-shaped cage stirring head 6, hopper 7 and valve plate 11 and other structural parts are preferably made of anti-corrosion and anti-static materials to adapt to the active chemical properties of the powder. The structural parts are preferably made of stainless steel and the surface is passivated. The electrical components adopt a higher IP protection level to prevent the powder from entering the device and causing a short circuit or component corrosion.

[0030] According to actual production needs, the equipment cost-effectiveness and applicable scope are comprehensively considered. Taking the commonly used weighing device with a weighing range of 0.01g to 150g and an accuracy of 0.005g as an example (the sensor's measuring range: 0 to 220g, accuracy: 0.001g), the weighing process of the heating powder, positive electrode powder, diaphragm powder and negative electrode powder used in the production of thermal batteries mainly includes the following steps:

[0031] 1) Pour the powder to be weighed into the hopper 7, and place the charging cup 12 on the weighing sensor; when the infrared sensor 13 senses the charging cup 12, the stirring motor 4 automatically starts, and the powder in the hopper 7 falls onto the valve plate 11 under the drive of the stirring motor 7;

[0032] 2) According to the target weighing value, the weighing controller controls the screw motor 15 to start, the screw 17 rotates, and the displacement of the nut 18 drives the drag plate 19 to move, driving the opening of the valve plate 11 to open, completing the first powder feeding, and forming the feeding data by comparing the real-time reading of the weighing sensor data with the fitting theory, and controlling the powder flow rate by adjusting the size of the opening of the valve plate 11 through the screw motor 15 with extremely fast response.

[0033] 3) When the actual weighing value fed back by the weighing sensor reaches 90%-95% of the target weighing value, the screw motor 15 starts, the screw 17 rotates, and the displacement of the nut 18 drives the carriage 19 to move left or right, so that the driving valve plate 11 connected to the carriage 19 moves left and right, thereby adjusting the opening size of the blanking mechanism to control the blanking speed;

[0034] 4) When the actual weighing value fed back by the weighing sensor reaches the target weighing value, the screw motor 15 controls the valve plate 11 to close the opening, and the weighing is completed.

[0035] 5) After weighing, the worker pours the powder in the filling cup 12 into a designated container or mold, replaces it with a clean cup and cleans the used cup;

[0036] 6) This reciprocating process can complete multiple weighing operations.

[0037] During the specific operation process, workers can be replaced by industrial robots to realize unmanned operation; the weighing time and weighing value can be uploaded to the production management system in the workshop to facilitate the information management of the entire manufacturing process.

[0038] The present invention can complete the weighing process of step 1) to step 6) in less than 30 seconds through the organic coordination of mechanical structure and electrical structure and reasonable optimization of software. The present invention can realize accurate automatic weighing of powder, free workers from the environment of pure manual operation, improve production efficiency, save human resources, and also avoid the adverse effects of dust particles on human health.

Claims

1. A chemical powder accurate weighing device, characterized by: It includes a weighing mechanism and a material dropping mechanism arranged above the weighing mechanism, the material dropping mechanism includes a hopper, a stirring assembly and a powder dropping assembly, wherein the stirring assembly is installed in the hopper, and the powder dropping assembly is installed at the discharge port of the hopper; the powder dropping assembly includes a supporting structure, a screw motor, a valve plate and a compression spring, wherein the supporting structure is installed at the bottom end of the discharge port of the hopper, the valve plate is installed at the discharge port of the hopper, and the valve plate is connected to the output shaft of the screw motor through a transmission member; the compression spring is arranged between the bottom of the valve plate and the supporting structure; The transmission member includes a linear guide rail, a lead screw, a nut and a carriage, wherein the lead screw is connected to the output shaft of the lead screw motor, the nut is meshed and transmission-connected with the lead screw, the carriage is fixedly connected to the nut, and the carriage is also fixedly connected to the valve plate; The stirring assembly includes a stirring motor, stirring wings, a Y-shaped cage stirring head and a flexible material brush, wherein the output shaft of the stirring motor is coaxially fixedly connected with the connecting rod, the bottom end of the connecting rod is connected with the Y-shaped cage stirring head, and the stirring wings are fixedly connected with the connecting rod by screws; the flexible material brush is fixedly connected with the side wall of the connecting rod through a connecting piece, and the brush surface of the flexible material brush contacts the inner wall of the hopper; It also includes a feedback control system, which includes a weighing sensor, a weighing controller, an infrared sensor and an industrial computer; the infrared sensor and the weighing sensor are installed on the weighing platform, the weighing controller communicates with the weighing sensor to feed back the current weight data to the control system online in real time, the weighing controller is connected to the industrial computer, and the infrared sensor is connected to the input end of the industrial computer; the feedback control system controls the stirring speed of the hopper and the leakage speed of the leakage actuator according to the remaining weight to be weighed; when the infrared sensor senses the charging cup, the stirring motor starts automatically, and the powder in the hopper falls onto the valve plate under the drive of the stirring motor, and according to the target weighing value, the weighing controller controls the screw motor to start, the screw rotates, and the valve is turned on. The displacement of the nut drives the carriage to move, driving the valve plate to open and completing the first powder feeding. The feeding data is formed by comparing the real-time read weighing sensor data with the fitting theory, and the powder flow rate is controlled by adjusting the size of the valve plate opening through the screw motor with extremely fast response. When the actual weighing value fed back by the weighing sensor reaches 90%-95% of the target weighing value, the screw motor starts and the screw rotates. The displacement of the nut drives the carriage to move left or right, so that the driving valve plate connected to the carriage moves left and right, and then the opening size of the blanking mechanism is adjusted to control the blanking speed. When the actual weighing value fed back by the weighing sensor reaches the target weighing value, the screw motor controls the valve plate to close the opening and the weighing is completed.

2. The chemical powder accurate weighing device according to claim 1, characterized in that: It also has a linear guide rail, which is horizontally arranged in its axial direction and fixedly installed on the overall frame of the weighing device in a side-standing form. The carriage is slidably connected to the linear guide rail through a slider.

3. The chemical powder accurate weighing device according to claim 1 is characterized in that: The supporting structure is a plate-shaped structural member, compression springs are respectively installed on both sides of the bottom of the structural member, and the hopper is installed in the main frame.

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