Aggregate bulk density automatic testing device and method

Abstract

The present invention discloses an automatic testing device and method for the bulk density of aggregates. The testing device includes a bracket with a capacity cylinder inside; a scraper is provided above the capacity cylinder, and the scraper reciprocates under the action of a driving mechanism; the bottom of the capacity cylinder is open, and a flap is provided at the bottom of the capacity cylinder, and the flap is rotatably arranged by a flip mechanism; a weighing hopper is provided below the capacity cylinder, and the weighing hopper is used to receive the material in the capacity cylinder, and a gate is provided at the discharge port of the weighing hopper; the driving mechanism and the flip mechanism are both connected to a control unit; the weighing hopper is carried on a weight sensor, and the weight sensor is connected to a processing unit to transmit the collected weight data to the processing unit, and the processing unit stores the capacity cylinder volume data, thereby calculating the bulk density. The present invention can realize automatic testing of bulk density, avoid related problems caused by excessive human factors, effectively improve test efficiency, and make the test results more objective and repeatable.

Description

Technical Field

[0001] The invention belongs to the technical field of bulk density detection, and in particular relates to an automatic testing device and method for aggregate bulk density. Background Art

[0002] Aggregate bulk density refers to the mass of material particles per unit volume of aggregate (including the solid particles and their closed and open pore volume and the volume of voids between particles). It is divided into dry bulk density and wet bulk density and is one of the important physical indicators of aggregate.

[0003] Currently, the bulk density of aggregates is primarily determined using the aggregate bulk density test specified in GB / T 14684-2022 Construction Sand and related industry standards. The test method is as follows: ① Loose bulk density: Take a sample and slowly pour it into a container 50 mm above the center using a funnel or spoon. Allow the sample to fall freely. Stop adding material when the sample forms a heap at the top of the container and the container is full on all sides. Avoid disturbing the container during the test. Use a ruler to smooth the edges along the centerline of the container opening. Weigh the total mass of the sample and container to the nearest 1g. ② Tight bulk density: Take a sample and place it into the container in two batches. After the first layer is filled (approximately slightly more than 1 / 2 the way through), place a 10 mm diameter round steel bar at the bottom of the container. Hold the container in place and tap it 25 times, alternating left and right. Then add the second layer. Once the second layer is full, use the same method to compact it, but place the steel bar at the bottom perpendicular to the first layer. Add more sample until it exceeds the mouth of the cylinder, then use a ruler to scrape it flat on both sides along the center line of the mouth of the cylinder, and weigh the total mass of the sample and the capacity cylinder to an accuracy of 1 g.

[0004] The existing aggregate bulk density test is completed entirely manually, with low test efficiency. In addition, the stratification and compaction during the test are greatly influenced by human subjectivity. The test results vary from person to person, are highly discrete, and have poor repeatability. Summary of the Invention

[0005] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide an automatic testing device and method for aggregate bulk density. The present invention can realize automatic testing of bulk density, avoid related problems caused by too many human factors, effectively improve test efficiency, and make test results more objective and repeatable.

[0006] The technical solution of the present invention is achieved as follows:

[0007] An automatic testing device for aggregate bulk density includes a bracket, which has a rectangular frame structure. A capacity cylinder is provided in the bracket. A plurality of fixed plates are provided on the circumferential outer wall corresponding to the upper end of the capacity cylinder, and are suspended and fixed in the bracket through the fixed plates; a scraper is provided above the capacity cylinder. Under the action of a driving mechanism, the lower edge of the scraper is in contact with the barrel mouth of the capacity cylinder and moves back and forth to scrape off the material on the upper surface of the barrel mouth of the capacity cylinder.

[0008] The bottom of the capacity cylinder is open, and a flap is provided at the bottom of the capacity cylinder. The flap can be rotatably set through a flip mechanism to realize the opening and closing of the bottom of the capacity cylinder; a weighing hopper is provided under the capacity cylinder, and the weighing hopper is used to receive the material in the capacity cylinder, and a gate door is provided at the discharge port of the weighing hopper for opening and closing the discharge port.

[0009] The driving mechanism and the turning mechanism are both connected to the control unit, so that the driving mechanism and the turning mechanism can be started and stopped by the control unit; a weight sensor is provided on the bracket, and the weighing hopper is carried on the weight sensor. The weight sensor is connected to the processing unit to transmit the collected weight data to the processing unit. The processing unit stores the volume data of the capacity cylinder, so as to calculate the stacking density.

[0010] Furthermore, a vibration motor is provided on the outer side wall of the capacity cylinder for driving the capacity cylinder to vibrate, and a control unit is connected to all the vibration motors to control the start and stop of the vibration motors.

[0011] Furthermore, all the fixed plates are combined to form a trumpet-shaped collecting hopper that is larger at the top and smaller at the bottom, which is used to collect the materials scraped off by the scraper; at the same time, a downward-slanting shuttle groove is provided at the lower end of one side of the collecting hopper to facilitate the materials in the collecting hopper to slide down from the shuttle groove.

[0012] Furthermore, a support platform is provided in the bracket, and the weight sensor is arranged on the support platform; it also includes a conveyor belt horizontally arranged below the support platform, and the conveyor belt is located below the shuttle trough and the discharge port of the weighing hopper, and is used to receive materials from the weighing hopper and the shuttle trough, and transport the materials to a recycling area.

[0013] Furthermore, the flipping mechanism includes a stepper motor, the rotating shaft of the flip plate is connected to the output shaft of the stepper motor, so that the flip plate can be driven to rotate by starting the stepper motor, and the stepper motor is arranged on the bracket; the control unit is connected to the stepper motor to control the start and stop of the stepper motor.

[0014] Furthermore, the gate door is connected to the rodless cylinder, so that the gate door can be moved by the rodless cylinder to realize the opening and closing of the discharge port of the weighing hopper. The rodless cylinder is set on the bracket, and the control unit is connected to the rodless cylinder to control the start and stop of the rodless cylinder.

[0015] Furthermore, the driving mechanism includes two servo motors and two electric modules, the two servo motors and the two electric modules are arranged in a one-to-one correspondence, and the output shaft of the servo motor is connected to the screw rod of the electric module, the two electric modules are horizontally arranged at the top of the bracket and parallel to each other, and the length direction of the two electric modules is parallel to the reciprocating motion direction of the scraper, and the scraper is composed of a scraper blade and a connecting rod arranged above the scraper blade. The two ends of the connecting rod extend out of the scraper blade by a certain length, and a card slot cooperating with the electric module is provided below the two ends of the connecting rod. The two card slots of the connecting rod are respectively clamped on the screw rods of the two electric modules, thereby driving the scraper to reciprocate along the length direction of the electric module.

[0016] Furthermore, the servo motor is connected to a control unit, so that the start and stop of the servo motor can be controlled by the control unit.

[0017] The present invention also provides an automatic test method for aggregate bulk density, comprising the following steps:

[0018] S1: Add material into the volumetric cylinder from the center above the mouth of the volumetric cylinder and let the material fall freely. When the material on the upper part of the volumetric cylinder forms a cone and the volumetric cylinder is full, stop adding material. If the bulk density is to be measured, proceed to S2, otherwise, go directly to S3.

[0019] S2: Start the vibration motor and vibrate the material in the capacity cylinder;

[0020] S3: Start the driving mechanism, so that the lower edge of the scraper is in contact with the opening of the capacity barrel and moves back and forth twice to scrape off the material on the upper surface of the opening of the capacity barrel. The scraped material is transported to the recycling area via the conveyor belt;

[0021] S4: Turn the flap to allow all the material in the volumetric cylinder to fall into the weighing hopper, and close the flap. After the weight data is transmitted to the processing unit and the bulk density is calculated, the gate door is opened to allow the material to fall onto the conveyor belt and be transported to the recycling area;

[0022] The above steps S2 to S4 are all automatically implemented under the control of the control unit.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The present invention adopts a driving mechanism to drive a scraper to move back and forth to scrape the material on the upper surface of the capacity cylinder, and adopts a vibration motor to compact the material to realize automatic testing of the bulk density, which not only improves the test efficiency, but also minimizes human participation and the test errors caused by it, and makes the test results less discrete and more repeatable. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the structure of the testing device of the present invention.

[0026] Figure 2 This is a structural schematic diagram of the testing device of the present invention from another perspective.

[0027] Among them: 1-servo motor; 2-electric module; 3-scraper; 4-capacity cylinder; 5-flip plate; 6-rodless cylinder; 7-conveyor belt; 8-shuttle slot; 9-stepping motor; 10-weighing hopper; 11-vibration motor; 12-gate door; 13-bracket. DETAILED DESCRIPTION

[0028] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] See also Figure 1 and Figure 2 An automatic testing device for aggregate bulk density includes a bracket 13, which has a rectangular frame structure. A capacity cylinder 4 is provided in the bracket 13, and a plurality of fixed plates are provided on the circumferential outer wall corresponding to the upper end of the capacity cylinder 4, and are suspended and fixed in the bracket 13 through the fixed plates; a scraper 3 is provided above the capacity cylinder 4, and under the action of the driving mechanism, the lower edge of the scraper is in contact with the mouth of the capacity cylinder 4 and moves back and forth to scrape off the material on the upper surface of the mouth of the capacity cylinder 4.

[0030] The bottom of the capacity cylinder 4 is open, and a flap 5 is provided at the bottom of the capacity cylinder 4. The flap 5 can be rotatably set through a flip mechanism to realize the opening and closing of the bottom of the capacity cylinder 4; a weighing hopper 10 is provided below the capacity cylinder 4, and the weighing hopper 10 is used to receive the material in the capacity cylinder 4, and a gate door 12 is provided at the discharge port of the weighing hopper 4 for opening and closing the discharge port.

[0031] The driving mechanism and the turning mechanism are both connected to the control unit, so that the driving mechanism and the turning mechanism can be started and stopped by the control unit. A weight sensor is installed on the bracket, and the bottom of the weighing hopper 10 is supported on the weight sensor. The weight sensor is connected to the processing unit to transmit the collected weight data to the processing unit. The processing unit stores the volume data of the capacity cylinder, so as to calculate the bulk density.

[0032] In this way, when the volumetric cylinder is filled with enough material to form a cone at the top and overflow around the perimeter, feeding is stopped. The material on the surface of the cylinder mouth can then be automatically scraped off by controlling the drive mechanism, eliminating the need for manual operation and effectively improving testing efficiency. The flap is then rotated to allow the material in the cylinder to enter the weighing hopper for weighing, thereby obtaining the weight m of the material in the cylinder. Since the volume v of the cylinder is known, the bulk density can be calculated as m / v. Of course, since the material in the cylinder is not compacted, the obtained bulk density is the loose bulk density.

[0033] In a specific implementation, a vibration motor 11 is provided on the outer wall of the capacity cylinder 4 for driving the capacity cylinder 4 to vibrate, and a control unit is connected to all the vibration motors 11 to control the start and stop of the vibration motors 11 .

[0034] A vibration motor is installed on the outer wall of the capacity cylinder to vibrate the material inside the capacity cylinder, thereby testing the bulk density. This eliminates the need for manual operation, thus avoiding the problems of human subjectivity in existing technologies, such as individual test results, large dispersion, and poor repeatability.

[0035] At the same time, since the capacity cylinder is set on the bracket, the vibration motor here will drive the bracket and the capacity cylinder to vibrate when it vibrates, but since the vibration amplitude of the capacity cylinder is relatively small, it will not affect the device.

[0036] During specific implementation, all the fixed plates are combined to form a trumpet-shaped collecting hopper that is larger at the top and smaller at the bottom, which is used to collect the materials scraped off by the scraper; at the same time, a downward-slanting shuttle groove 8 is provided at the lower end of one side of the collecting hopper to facilitate the materials in the collecting hopper to slide down from the shuttle groove 8.

[0037] During specific implementation, a support platform is provided in the bracket 13, and the weight sensor is arranged on the support platform; it also includes a conveyor belt 7 horizontally arranged below the support platform, and the conveyor belt 7 is located below the shuttle slot 8 and the discharge port of the weighing hopper 10, and is used to receive materials from the weighing hopper 10 and the shuttle slot 8, and transport the materials to the recycling area.

[0038] The weighing hopper 4 discharge port and the shuttle slot 8 outlet are located on opposite sides of the frame. Because the weighing hopper 4 discharge port is located at a high altitude from the conveyor belt, material can easily splash onto the conveyor belt during discharge. To address this, guide grooves extend downward at the same angle from the weighing hopper 4 discharge port, lowering the height of the discharge port relative to the conveyor belt. To prevent spillage, baffles are installed on the left and right sides of the conveyor belt, with both ends extending a suitable distance from the frame.

[0039] In this way, the materials in the shuttle trough and weighing hopper can be sent to the recycling area for recycling through the conveyor belt, avoiding the impact of materials scraped by the scraper on the environment, which is conducive to keeping the area around the device clean and tidy. It also avoids the use of manual material transfer, saves manpower and improves test efficiency.

[0040] During specific implementation, the flipping mechanism includes a stepper motor 9, and the rotating shaft of the flip plate 5 is connected to the output shaft of the stepper motor 9, so that the flip plate 5 can be driven to rotate by starting the stepper motor 9. The stepper motor 9 is set on the bracket 13; the control unit is connected to the stepper motor 9 to control the start and stop of the stepper motor 9.

[0041] During specific implementation, the gate door 12 is connected to the rodless cylinder 6, so that the gate door 12 can be driven to move by the rodless cylinder 6 to realize the opening and closing of the discharge port of the weighing hopper 10. The rodless cylinder 6 is set on the bracket 13, and the control unit is connected to the rodless cylinder 6 to control the start and stop of the rodless cylinder 6.

[0042] During specific implementation, the driving mechanism includes two servo motors 1 and two electric modules 2. The servo motors 1 and the electric modules 2 are arranged in a one-to-one correspondence, and the output shaft of the servo motor 1 is connected to the screw of the electric module 2. The two electric modules 2 are horizontally arranged at the top of the bracket 13 and are parallel to each other. The length direction of the two electric modules 2 is parallel to the reciprocating motion direction of the scraper 3. The scraper 3 is composed of a scraper and a connecting rod arranged above the scraper. The two ends of the connecting rod extend out of the scraper for a certain length, and a slot cooperating with the electric module is provided below the two ends of the connecting rod. The two slots of the connecting rod are respectively clamped on the screws of the two electric modules, thereby driving the scraper to reciprocate along the length direction of the electric module.

[0043] During specific implementation, the servo motor 1 is connected to a control unit so as to control the start and stop of the servo motor 1 through the control unit.

[0044] The bulk density is tested using the above-mentioned aggregate bulk density automatic testing device, including the following steps:

[0045] S1: First, ensure the equipment is in its initial state. For example, the bottom of the capacity cylinder is sealed and the gate door is closed. Move the scraper to the outside of the capacity cylinder. Then, add material from above the center of the capacity cylinder mouth and let the material fall freely. When the material at the top of the capacity cylinder forms a cone and the capacity cylinder is full on all sides, stop adding material. If you want to measure the compacted bulk density, proceed to S2; otherwise, proceed directly to S3. Material can be added manually or automatically. Design the material drop height according to the standard.

[0046] S2: Start the vibration motor and vibrate the material in the capacity cylinder;

[0047] S3: Start the driving mechanism, so that the lower edge of the scraper is in contact with the opening of the capacity barrel and moves back and forth twice to scrape off the material on the upper surface of the opening of the capacity barrel. The scraped material is transported to the recycling area via the conveyor belt;

[0048] S4: Turn the flap to make all the materials in the capacity cylinder fall into the weighing hopper, and close the flap. After the weight data is transmitted to the processing unit and the bulk density is calculated, the gate door is opened to make the materials fall into the conveyor belt and be transported to the recycling area.

[0049] The above steps S2 to S4 are all automatically implemented under the control of the control unit. To ensure the accuracy of the test, steps S1 to S4 can be repeated to take the average value of the results of multiple parallel tests as the measured value.

[0050] Finally, it should be noted that the above embodiments of the present invention are merely examples for illustrating the present invention and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations and modifications can be made based on the above description. It is not possible to enumerate all embodiments here. Any obvious variations or modifications arising from the technical solution of the present invention remain within the scope of protection of the present invention.

Claims

1. An automatic testing device for aggregate bulk density, characterized in that: The bracket comprises a rectangular frame structure, wherein a capacity cylinder is provided in the bracket, and a plurality of fixing plates are provided on the circumferential outer wall corresponding to the upper end of the capacity cylinder, and are suspended and fixed in the bracket by the fixing plates; a scraper is provided above the capacity cylinder, and under the action of a driving mechanism, the scraper moves back and forth with the lower edge thereof in contact with the opening of the capacity cylinder to scrape off the material on the upper surface of the opening of the capacity cylinder; The bottom of the capacity cylinder is open, and a flap is provided at the bottom of the capacity cylinder. The flap can be rotated by a turning mechanism to realize the opening and closing of the bottom of the capacity cylinder. A weighing hopper is provided below the capacity cylinder, and the weighing hopper is used to receive the material in the capacity cylinder. A gate door is provided at the discharge port of the weighing hopper for opening and closing the discharge port. The driving mechanism and the turning mechanism are both connected to a control unit, so that the driving mechanism and the turning mechanism can be started and stopped by the control unit. A weight sensor is provided on the bracket, and the weighing hopper is carried on the weight sensor. The weight sensor is connected to a processing unit to transmit the collected weight data to the processing unit. The processing unit stores the volume data of the capacity cylinder, thereby calculating the bulk density. A vibration motor is provided on the outer wall of the capacity cylinder for driving the capacity cylinder to vibrate, and a control unit is connected to all the vibration motors to control the start and stop of the vibration motors; All the fixed plates together form a trumpet-shaped collecting hopper that is larger at the top and smaller at the bottom, which is used to collect the materials scraped off by the scraper. At the same time, a downward-sloping shuttle groove is provided at the lower end of one side of the collecting hopper to facilitate the materials in the collecting hopper to slide down from the shuttle groove. A support platform is provided in the bracket, and the weight sensor is provided on the support platform; a conveyor belt is also provided horizontally below the support platform, and the conveyor belt is located below the shuttle slot and the discharge port of the weighing hopper, and is used to receive materials from the weighing hopper and the shuttle slot, and transport the materials to a recycling place; The driving mechanism includes two servo motors and two electric modules. The two servo motors and the two electric modules are arranged in a one-to-one correspondence, and the output shaft of the servo motor is connected to the screw rod of the electric module. The two electric modules are horizontally arranged at the top of the bracket and parallel to each other. The length direction of the two electric modules is parallel to the reciprocating motion direction of the scraper. The scraper is composed of a scraper blade and a connecting rod arranged above the scraper blade. The two ends of the connecting rod extend out of the scraper blade for a certain length, and a card slot cooperating with the electric module is provided below the two ends of the connecting rod. The two card slots of the connecting rod are respectively clamped on the screw rods of the two electric modules, thereby driving the scraper to reciprocate along the length direction of the electric module.

2. The automatic testing device for aggregate bulk density according to claim 1, characterized in that: The flipping mechanism includes a stepper motor, and the rotating shaft of the flip plate is connected to the output shaft of the stepper motor, so that the flip plate can be driven to rotate by starting the stepper motor. The stepper motor is set on the bracket; the control unit is connected to the stepper motor to control the start and stop of the stepper motor.

3. The automatic testing device for aggregate bulk density according to claim 1, characterized in that: The gate door is connected to the rodless cylinder, which makes it convenient for the rodless cylinder to drive the gate door to move, so as to realize the opening and closing of the discharge port of the weighing hopper. The rodless cylinder is set on the bracket, and the control unit is connected to the rodless cylinder to control the start and stop of the rodless cylinder.

4. The automatic testing device for aggregate bulk density according to claim 1, characterized in that: The servo motor is connected to the control unit so that the start and stop of the servo motor can be controlled by the control unit.

5. An automatic test method for aggregate bulk density, characterized in that: The test is performed using the automatic aggregate bulk density test device according to any one of claims 1 to 4, comprising the following steps: S1: Add material into the volumetric cylinder from the center above the mouth of the volumetric cylinder and let the material fall freely. When the material on the upper part of the volumetric cylinder forms a cone and the volumetric cylinder is full, stop adding material. If the bulk density is to be measured, proceed to S2, otherwise, go directly to S3. S2: Start the vibration motor and vibrate the material in the capacity cylinder; S3: Start the driving mechanism, so that the lower edge of the scraper is in contact with the opening of the capacity barrel and moves back and forth twice to scrape off the material on the upper surface of the opening of the capacity barrel. The scraped material is transported to the recycling area via the conveyor belt; S4: Turn the flap to allow all the material in the volumetric cylinder to fall into the weighing hopper, and close the flap. After the weight data is transmitted to the processing unit and the bulk density is calculated, the gate door is opened to allow the material to fall onto the conveyor belt and be transported to the recycling area; The above steps S2 to S4 are all automatically implemented under the control of the control unit.

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