Negative pressure weighing device

Abstract

The utility model provides a negative pressure weighing device, relates to the negative pressure weighing technology field, and comprises a weighing chamber body, a negative pressure cavity and a weighing cavity, the negative pressure cavity and the weighing cavity are distributed up and down in the weighing chamber body, the bottom of the negative pressure cavity is embedded and rotatably connected with a rotating disc, the edge of the upper surface of the rotating disc is arranged in an annular hollow-out manner, and the rotating disc is provided with a hollow-out opening. A hollow part in the rotating disc communicates with a negative pressure cavity and a weighing cavity, a filtering part is mounted in the hollow part, mounting frames are fixedly mounted at the bottom of the negative pressure cavity and the top of the weighing cavity, the positions of the upper box body and the lower box body are moved, and sealing rings in the upper box body and the lower box body extend out to be attached to the upper surface and the lower surface of the filtering part correspondingly; vibration of the filtering pieces is achieved through vibration, deep dust of the filtering pieces is shaken off and loosened, cleaning of the filtering faces at the top ends of the filtering pieces is achieved through rotation of the brushes in the sealing rings at the upper positions, when one filtering piece is cleaned, use of equipment can still be guaranteed through other filtering pieces, and weighing work cannot be affected.

Description

Technical Field

[0001] This utility model relates to the field of negative pressure weighing technology, and in particular to a negative pressure weighing device. Background Technology

[0002] Negative pressure weighing is a device that combines negative pressure technology and weighing technology. It is mainly used in pharmaceutical, microbiological research, and scientific experiments. A negative pressure weighing chamber (also known as a negative pressure weighing hood or weighing chamber) is an air purification device that provides local negative pressure and a local Class A environment. Through its vertical unidirectional airflow design, it effectively ensures a high level of cleanliness in the work area and prevents cross-contamination.

[0003] Therefore, a prior art negative pressure weighing chamber, disclosed in CN221684687U, includes a weighing chamber body. Within the weighing chamber body, a weighing cavity, a hollow cavity, and a negative pressure cavity are sequentially connected end-to-end. A suction fan is installed near the top of the hollow cavity, and the suction fan is connected to the negative pressure cavity located directly above the weighing cavity via a suction pipe. A filter insert cavity is provided at the connection between the weighing cavity and the hollow cavity, into which a first filter is inserted. A third filter is also inserted at the connection between the negative pressure cavity and the weighing cavity. The first and third filters are connected within the filter insert cavities, and the filters can be easily replaced using a filter handle.

[0004] However, during the process of disassembling and cleaning the third filter, the equipment needs to be stopped and waited because it loses the filtering function of the third filter. The downtime will directly affect the progress of the weighing operation. Utility Model Content

[0005] The purpose of this utility model is to solve the problems existing in the prior art and to propose a negative pressure weighing device.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a negative pressure weighing device, comprising a weighing chamber body and a negative pressure cavity and a weighing cavity arranged vertically within the weighing chamber body. A turntable is rotatably connected to the bottom of the negative pressure cavity. The upper surface edge of the turntable is perforated in an annular shape. The perforation on the turntable connects the negative pressure cavity and the weighing cavity, and a filter element is installed within the perforation. Mounting brackets are fixedly installed at the bottom of the negative pressure cavity and the top of the weighing cavity. An upper box body that slides relative to the center line of the turntable is inserted into the side of the mounting bracket on the negative pressure cavity. A lower box body that slides relative to the center line of the turntable is inserted into the mounting bracket inside the weighing cavity. The upper box body and the lower box body are located on the same side of the turntable and their openings face each other. A sealing ring for covering the periphery of the filter element is fitted at the opening of both the upper box body and the lower box body. A brush is rotatably connected within the sealing ring inside the upper box body.

[0007] Preferably, a horizontally arranged electric push rod is fixedly installed on the side of the mounting bracket, and the telescopic end of the electric push rod in the negative pressure cavity is connected to the outer wall of the upper box, while the telescopic end of the electric push rod in the weighing cavity is connected to the outer wall of the lower box.

[0008] Preferably, a plurality of pneumatic telescopic rods are fixedly installed on the inner side wall of the sealing ring near the filter element. The pneumatic telescopic rods located above the turntable are connected to the interior of the upper box, and the pneumatic telescopic rods located below the turntable are connected to the inner wall of the lower box.

[0009] Preferably, a vibrating rod is rotatably connected inside the sealing ring in the lower housing. The vibrating rod and the brush are respectively used to adhere to the bottom and top surfaces of the same filter element and are both driven by a motor.

[0010] Preferably, a return air pipe is provided through the bottom of the negative pressure chamber near the mounting bracket, and the bottom end of the return air pipe extends into the weighing chamber and is arranged in an L-shape and is inserted into the air inlet on the side of the lower box.

[0011] Preferably, an air outlet pipe is provided in the known air outlet on one side of the negative pressure cavity wall, and one end of the air outlet pipe is inserted into the air outlet on the side of the upper box.

[0012] Preferably, the weighing chamber has several fixed frames arranged in a circular array around the turntable, each fixed frame corresponding to a number of filter elements, and a sealing plate for sealing the bottom of the filter element is inserted into any fixed frame. An electric telescopic rod is connected between the sealing plate and the fixed frame.

[0013] Compared with the prior art, the advantages and positive effects of this utility model are as follows:

[0014] 1. In this utility model, by moving the positions of the upper and lower boxes, and using the internal sealing rings to extend and fit against the upper and lower surfaces of the filter element respectively, the filter element is vibrated by vibration, which shakes off and loosens the dust in the filter element. The brush inside the upper sealing ring rotates to clean the top filter surface of the filter element. While cleaning one filter element, the other filter elements can still be used to ensure the operation of the equipment and will not affect the weighing operation.

[0015] 2. In this utility model, part of the air blown downward by the negative pressure chamber is blown into the lower box through the return air pipe. Under the sealing effect of the sealing ring, part of the airflow rises in the opposite direction and blows back through the back of the filter being cleaned. This allows the dust that has fallen off the filter by the brush to be blown out along the upper box and the air outlet pipe. Attached Figure Description

[0016] Figure 1 A three-dimensional structural diagram of a negative pressure weighing device is provided for this utility model;

[0017] Figure 2 This utility model provides a schematic diagram of the top structure of the weighing chamber of a negative pressure weighing device;

[0018] Figure 3 This utility model proposes a negative pressure weighing device. Figure 2 A top-view structural diagram;

[0019] Figure 4 for Figure 3 A cross-sectional structural diagram.

[0020] Legend: 1. Weighing chamber body; 2. Weighing cavity; 3. Negative pressure cavity; 4. Turntable; 5. Fixing frame; 6. Sealing plate; 7. Electric telescopic rod; 8. Lower box; 9. Return air duct; 10. Electric push rod; 11. Mounting frame; 12. Filter element; 13. Upper box; 14. Air outlet duct; 15. Brush; 16. Vibrator; 17. Sealing ring; 18. Pneumatic telescopic rod. Detailed Implementation

[0021] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0022] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed in the following specification.

[0023] like Figure 1-4As shown, a negative pressure weighing device includes a weighing chamber body 1 and a negative pressure cavity 3 and a weighing cavity 2 arranged vertically within the weighing chamber body 1. A turntable 4 is rotatably connected to the bottom of the negative pressure cavity 2. The upper surface edge of the turntable 4 is perforated in an annular shape. The perforation on the turntable 4 connects the negative pressure cavity 3 and the weighing cavity 2, and a filter element 12 is installed in the perforation. The filter element 12 can be commercially available filter cotton or other related materials and products used for air filtration. Mounting brackets 11 are fixedly installed at the bottom of the negative pressure cavity 3 and the top of the weighing cavity 2. An upper box 13 that slides relative to the center line of the turntable 4 is inserted into the side of the mounting bracket 11 on the negative pressure cavity 3. The mounting bracket 11 in the weighing cavity 2 is also fixedly installed with the upper box 13 that slides relative to the center line of the turntable 4. A lower box 8 is inserted into the frame 11 and slides relative to the center line of the turntable 4. A horizontally arranged electric push rod 10 is fixedly installed on the side of the mounting frame 11. The telescopic end of the electric push rod 10 in the negative pressure chamber 3 is connected to the outer wall of the upper box 13. The telescopic end of the electric push rod 10 in the weighing chamber 3 is connected to the outer wall of the lower box 8. In actual use, the upper box 13 can be moved to the top of the turntable 4 and above the filter element 12 on one side by extending the electric push rod 10 at the upper position. Similarly, the lower box 8 can be moved to the bottom of the turntable 4 and below the filter element 12 on one side by extending the electric push rod 10 at the lower position. The upper box 13 and the lower box 8 are arranged opposite to each other.The upper box 13 and the lower box 8 are located on the same side of the turntable 4 with their openings facing each other. Both the upper box 13 and the lower box 8 have sealing rings 17 fitted at their openings to cover the periphery of the filter element 12. A brush 15 is rotatably connected inside the sealing ring 17 in the upper box 13. Several pneumatic telescopic rods 18 are fixedly installed on the inner wall of the sealing ring 17 near the filter element 12. The pneumatic telescopic rods 18 located above the turntable 4 are connected to the interior of the upper box 13, and the pneumatic telescopic rods 18 located below the turntable 4 are connected to the inner wall of the lower box 8. When the upper box 13 and the lower box 8 move to the same position above and below the filter element 12, the extension of the pneumatic telescopic rods 18 in the upper box 13 allows the sealing rings 17 inside the upper box 13 to descend to the port and fit above the filter element 12. Similarly, the extension of the pneumatic telescopic rods 18 in the lower box 8 allows the sealing rings 17 inside the lower box 8 to rise to the port and fit above the filter element 12. Below, a vibrating rod 16 is rotatably connected within a sealing ring 17 inside the lower housing 8. The vibrating rod 16 and brush 15 are respectively used to adhere to the bottom and top surfaces of the same filter element 12 and are both driven by a motor. The vibrating rod 16 within the sealing ring 17 rotates to adhere to different positions on the bottom of the filter element 12, vibrating to shake and loosen the dust from the filter element 12. The brush 15 within the sealing ring 17 rotates to clean the top surface of the filter element 12. While cleaning one filter element 12, the other filter elements 12 can still be used, ensuring the equipment continues to operate without affecting the weighing process. Therefore, a motor can be installed on the top of the weighing chamber 2 to drive the turntable 4 to rotate, allowing each filter element 12 on the edge of the turntable 4 to pass between the upper housing 13 and the lower housing 8 for individual cleaning.

[0024] Furthermore: A return air pipe 9 is installed through the bottom of the negative pressure chamber 3 near the mounting bracket 11. The bottom end of the return air pipe 9 extends into the weighing chamber 2 and is L-shaped, connecting to the air inlet on the side of the lower box 8. An air outlet pipe 14 is installed in the known air outlet on one side of the negative pressure chamber 3. One end of the air outlet pipe 14 is connected to the air outlet on the side of the upper box 13. Part of the air blown downward by the negative pressure chamber 3 is blown into the lower box 8 through the return air pipe 9. Under the sealing effect of the sealing ring 17, part of the airflow rises in the opposite direction and blows against the back of the filter element 12 being cleaned. This allows the dust that has fallen off the filter element 12 by the brush 15 to be blown out along the upper box 13 and the air outlet pipe 14. In addition, when the sealing ring 17 in the lower box 8 is not extended, its side blocks the air inlet of the lower box 8, thereby preventing unfiltered air from directly entering the weighing chamber 2 along the return air pipe 9 and the lower box 8.

[0025] Furthermore, the weighing chamber 2 has several fixed frames 5 arranged in a ring array around the turntable 4. Each fixed frame 5 corresponds to a number of filter elements 12, and a sealing plate 6 for sealing the bottom of the filter element 12 is inserted into any fixed frame 5. An electric telescopic rod 7 is connected between the sealing plate 6 and the fixed frame 5. In use, the electric telescopic rod 7 at a specific position can be extended to move the corresponding sealing plate 6 toward the central axis of the turntable 4 until the bottom of the filter element 12 at the corresponding position is sealed. This allows control over the number and position of the filter elements 12 used, and facilitates adjustment of the air intake of the weighing chamber 2.

[0026] Working principle: During use, the electric push rod 10 at the top extends, moving the upper box 13 above the turntable 4 and above the filter element 12 on one side. Similarly, the electric push rod 10 at the bottom extends, moving the lower box 8 below the turntable 4 and below the filter element 12 on one side. The turntable 4 is rotated by a motor, causing the filter element 12 at the edge of the turntable 4 to pass between the upper box 13 and the lower box 8. When the filter element 12 reaches between the upper box 13 and the lower box 8, the pneumatic telescopic rod 1 inside the upper box 13... The extension of the upper box 13 causes the sealing ring 17 to descend to the port and fit above the filter element 12. The extension of the pneumatic telescopic rod 18 in the lower box 8 causes the sealing ring 17 in the lower box 8 to rise to the port and fit below the filter element 12. The vibration of the vibrating rod 16 causes the filter element 12 to vibrate, thus shaking off and loosening the dust in the filter element 12. The brush 15 in the upper sealing ring 17 rotates to clean the top filter surface of the filter element 12. With the help of the set return air pipe 9 and the air outlet pipe 14, the cleaned dust is directly discharged along the air outlet of the negative pressure chamber 3.

[0027] The wiring diagrams of the electric telescopic rod 7, electric push rod 10, motor, vibrating rod 16, and pneumatic telescopic rod 18 in this utility model are common knowledge in the field. Their working principles are known technologies. The appropriate model is selected according to actual use. Therefore, the control methods and wiring layouts of the electric telescopic rod 7, electric push rod 10, motor, vibrating rod 16, and pneumatic telescopic rod 18 will not be explained in detail.

[0028] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model shall still fall within the protection scope of the present utility model.

Claims

1. A negative pressure weighing device, comprising a weighing chamber body (1) and a negative pressure cavity (3) and a weighing cavity (2) arranged vertically within the weighing chamber body (1), characterized in that: The bottom of the negative pressure chamber (3) is rotatably connected to a turntable (4). The upper surface edge of the turntable (4) is perforated in a ring shape. The perforation on the turntable (4) connects the negative pressure chamber (3) and the weighing chamber (2), and a filter element (12) is installed in the perforation. Mounting brackets (11) are fixedly installed at the bottom of the negative pressure chamber (3) and the top of the weighing chamber (2). The mounting brackets (11) on the negative pressure chamber (3) are inserted into the side of a sliding plate relative to the center line of the turntable (4). The upper box (13) and the mounting bracket (11) inside the weighing chamber (2) are connected to a lower box (8) that slides relative to the center line of the turntable (4). The upper box (13) and the lower box (8) are located on the same side of the turntable (4) and their openings face each other. Both the upper box (13) and the lower box (8) are fitted with sealing rings (17) for covering the periphery of the filter element (12). A brush (15) is rotatably connected inside the sealing ring (17) inside the upper box (13).

2. The negative pressure weighing device according to claim 1, characterized in that: The mounting bracket (11) is fixedly mounted with a horizontally arranged electric push rod (10) on its side, and the telescopic end of the electric push rod (10) in the negative pressure cavity (3) is connected to the outer wall of the upper box (13), and the telescopic end of the electric push rod (10) in the weighing cavity (2) is connected to the outer wall of the lower box (8).

3. The negative pressure weighing device according to claim 1, characterized in that: Several pneumatic telescopic rods (18) are fixedly installed on the inner side wall of the sealing ring (17) near the filter element (12). The pneumatic telescopic rods (18) located above the turntable (4) are connected to the inside of the upper box (13), and the pneumatic telescopic rods (18) located below the turntable (4) are connected to the inner wall of the lower box (8).

4. The negative pressure weighing device according to claim 1, characterized in that: A vibrating rod (16) is rotatably connected inside the sealing ring (17) inside the lower box (8). The vibrating rod (16) and the brush (15) are respectively used to adhere to the bottom and top surfaces of the same filter element (12) and are both driven by a motor.

5. The negative pressure weighing device according to claim 1, characterized in that: The bottom of the negative pressure chamber (3) is provided with a return air pipe (9) near the mounting bracket (11). The bottom end of the return air pipe (9) extends into the weighing chamber (2) and is arranged in an L-shape and is inserted into the air inlet on the side of the lower box (8).

6. The negative pressure weighing device according to claim 5, characterized in that: An air outlet pipe (14) is provided in the known air outlet on one side of the negative pressure cavity (3), and one end of the air outlet pipe (14) is inserted into the air outlet on the side of the upper box (13).

7. The negative pressure weighing device according to claim 1, characterized in that: The weighing chamber (2) has several fixed frames (5) arranged in a ring array around the turntable (4) on its top. Each of the fixed frames (5) corresponds to a number of filter elements (12), and a sealing plate (6) for sealing the bottom of the filter element (12) is inserted into any fixed frame (5). An electric telescopic rod (7) is connected between the sealing plate (6) and the fixed frame (5).

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