A personal respirable dust sampling flow calibration connection device

Abstract

This utility model discloses a connection device for individual respirable dust sampling flow calibration, which solves the problems of poor compatibility, insufficient sealing, inconvenient filter membrane installation and removal, and lack of fixing structure in existing connection devices. The device includes an upper sleeve, a connecting sleeve, and a lower sleeve. The upper sleeve has an upper groove, a middle groove, and an upper fixing groove inside, with an upper connecting tube extending from the top. A buckle is provided on the outer wall of the middle groove. The upper part of the connecting sleeve is connected to the upper sleeve via threads, and a circular filter membrane and a circular washer are sandwiched in the lower circular groove, which has an internal connecting thread. The top of the lower sleeve is connected to the connecting sleeve via threads, and a lower connecting tube extends from the bottom. The lower connecting ring has a conical groove at the bottom of its inner ring. The device prevents airflow leakage through a multi-layer sealing structure, uses buckles for fixing, is compatible with different equipment, facilitates filter membrane installation and removal, ensures calibration accuracy and operational stability, and is suitable for dust sampling flow calibration in the workplace.

Description

Technical Field

[0001] This utility model belongs to the technical field of sampling equipment connection devices, specifically relating to a flow rate calibration connection device for individual respirable dust sampling. Background Technology

[0002] Respirable dust is a significant threat to human health. To assess workplace dust pollution levels and protect occupational health, it is necessary to sample and monitor respirable dust in the air using individual respirable dust sampling devices. The accuracy of the sampling flow rate directly determines the reliability of the sampling results. Therefore, calibrating the flow rate of the sampling device before and after sampling is an indispensable and crucial step in dust monitoring.

[0003] Currently, there are many shortcomings in the connection devices available on the market for calibrating individual respiratory dust sampling flow rates, mainly in the following aspects:

[0004] (1) Poor interface compatibility: The interface specifications of existing connection devices are relatively fixed, making it difficult to adapt to different brands and models of sampling and flow calibration devices. This results in staff having to prepare multiple connection devices in actual operation, increasing equipment carrying costs and operational complexity, and reducing on-site calibration efficiency.

[0005] (2) Insufficient sealing: During calibration, the sealing of the connection points directly affects the accuracy of flow measurement. Traditional connection devices often use simple socket or snap-fit ​​structures, which are prone to problems such as aging of seals and loosening of interfaces after long-term use, leading to air leakage and thus causing deviation in flow calibration data, which cannot truly reflect the actual working status of the sampling equipment.

[0006] (3) Inconvenient installation and replacement of filter membrane: During the calibration of respirable dust sampling, a filter membrane is required to simulate the actual sampling environment. The existing filter membrane installation structure is often quite complex. Special tools are needed to disassemble and replace the filter membrane. The operation steps are cumbersome, which not only wastes time, but may also damage the filter membrane during the operation, affecting the calibration effect.

[0007] To address the shortcomings of existing technologies, there is an urgent need for a personal respirable dust sampling flow calibration connection device that is highly compatible, has good sealing performance, is easy to install and remove filter membranes, and has a fixed function, in order to solve the pain points in current dust sampling flow calibration work and improve calibration efficiency and data accuracy. Utility Model Content

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a connection device for individual respirable dust sampling flow calibration, so as to solve the problems of poor compatibility, insufficient sealing, inconvenient filter membrane installation and lack of fixed structure of the existing connection device, and ensure the accuracy and ease of operation of individual respirable dust sampling flow calibration.

[0009] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0010] A personal respirable dust sampling flow calibration connection device includes: an upper sleeve, a connecting sleeve, and a lower sleeve;

[0011] The upper sleeve has an upper connecting groove, a middle connecting groove and an upper fixing groove arranged from top to bottom. The upper connecting groove, the middle connecting groove and the upper fixing groove are all circular and their diameters increase sequentially.

[0012] The upper part of the connecting sleeve is provided with an upper connecting ring and an upper fixing ring. The outer wall of the upper fixing ring is provided with a fixing external thread, and the inner wall of the upper fixing groove is provided with a matching fixing internal thread. The connecting sleeve is installed in the upper connecting sleeve by threaded connection. The diameter of the upper connecting ring is the same as the diameter of the middle connecting groove, and the upper connecting ring is placed in the middle connecting groove.

[0013] The lower inner side of the connecting sleeve is provided with a circular groove for placing objects. Two circular washers and a circular filter membrane are arranged in sequence in the circular groove, and the circular filter membrane is sandwiched between the two circular washers.

[0014] The lower part of the circular groove is provided with an internal thread, the top of the lower sleeve is provided with a lower connecting ring, the outer wall of the lower connecting ring is provided with an external thread that matches the internal thread, and the lower sleeve is installed at the bottom of the connecting sleeve by a threaded connection.

[0015] The upper sleeve has an upper connecting tube extending vertically upward from its top, and the lower sleeve has a lower connecting tube extending vertically downward from its bottom.

[0016] Furthermore, a circular gap is formed between the upper connecting ring and the top groove surface of the middle connecting groove, and a middle connecting washer is provided in the circular gap;

[0017] The top edge of the central groove is provided with an annular groove, and the edge of the central washer protrudes upward to form a central ring, which is embedded in the annular groove.

[0018] The bottom edge of the intermediate washer is provided with an upper ring groove with a semi-circular cross-section, and the top surface of the upper connecting ring is provided with a matching lower ring groove with a semi-circular cross-section. The upper ring groove and the lower ring groove are aligned and spliced ​​to form a circular cavity, and a circular ring is provided inside the circular cavity.

[0019] Furthermore, the lower part of the inner ring of the lower connecting ring is a funnel-shaped conical groove that communicates with the lower connecting sleeve.

[0020] Furthermore, the outer wall side of the central groove is provided with a buckle for fixing the device to clothing.

[0021] Furthermore, the upper and lower connecting sleeves are used to connect the sampling device and the flow calibration device, respectively.

[0022] Furthermore, the circular filter membrane is a filter membrane for sampling respirable dust, and its diameter matches the diameter of the circular groove for placing the sample.

[0023] The beneficial effects of this utility model are:

[0024] (1) Strong compatibility and wide range of applications: This device connects the sampling equipment and the flow calibration equipment through the upper and lower sleeves respectively. The overall structure does not limit the specific interface specifications. It can be adapted to different brands and models of sampling equipment and flow calibration equipment according to actual needs. There is no need for staff to carry multiple specifications of connecting devices, which significantly reduces the cost of carrying equipment and improves the convenience and efficiency of on-site calibration operations.

[0025] (2) Multiple sealing structure to ensure calibration accuracy: The device is designed with multiple sealing structures at key connection parts: a middle connection gasket is set in the circular gap between the upper connecting ring and the middle connection groove, and the middle connection ring of the middle connection gasket is embedded in the annular groove, which can effectively prevent airflow from leaking from this part; at the same time, an annular ring is set in the annular cavity formed by splicing the upper annular groove of the middle connection gasket and the lower annular groove of the upper connecting ring, which further enhances the sealing performance; in addition, the connecting sleeve and the upper connecting sleeve (1) and the lower connecting sleeve are all threaded. The threaded fit can further improve the sealing of the connection part, avoid the deviation of flow calibration data caused by airflow leakage, and ensure the accuracy of calibration results.

[0026] (3) Convenient filter membrane installation and removal, and high operation efficiency: The inner side of the lower part of the connecting sleeve provides a dedicated installation space for the circular filter membrane and the circular gasket. The lower sleeve and the connecting sleeve are connected by threads. After removing the lower sleeve, the circular filter membrane and the circular gasket can be directly placed into or taken out of the circular slot without the need for special tools. The operation steps are simple, which greatly shortens the filter membrane replacement time and improves the calibration operation efficiency. At the same time, the circular filter membrane is sandwiched between two circular gaskets, which can prevent the filter membrane from shifting or being damaged during installation and use, and ensure the normal use of the filter membrane.

[0027] (4) Built-in fixing structure to improve operational stability: The outer wall of the central slot is equipped with buckles, which allow staff to fix the entire device to clothing (such as the edge of work clothes pockets, collars, etc.) or other convenient carriers. This eliminates the need to hold the device for a long time for calibration operations, reducing arm fatigue and avoiding unstable device connection caused by hand tremors, further ensuring the stability of the calibration process and the accuracy of calibration data. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a three-dimensional schematic diagram of the device of this utility model;

[0030] Figure 2 This is an internal sectional view of the device of this utility model;

[0031] Figure 3 This is an exploded schematic diagram of the device of this utility model;

[0032] Figure 4 This is an internal sectional view of the upper sleeve of this utility model;

[0033] Figure 5 This is an internal sectional view of the upper connecting groove of this utility model;

[0034] Figure 6 This is an internal sectional view of the lower sleeve of this utility model;

[0035] Figure 7 This is a schematic diagram of the intermediate washer structure of this utility model.

[0036] 1-Upper connecting sleeve, 11-Upper connecting groove, 12-Middle connecting groove, 121-Annular groove, 13-Upper fixing groove, 131-Fixing internal thread, 14-Upper connecting sleeve, 2-Connecting sleeve, 21-Upper connecting ring, 211-Lower annular groove, 22-Upper fixing ring, 221-Fixing external thread, 23-Placement circular groove, 24-Connecting internal thread, 3-Lower connecting sleeve, 31-Lower connecting ring, 32-Connecting external thread, 33-Lower connecting sleeve, 34-Conical groove, 4-Circular washer, 5-Circular filter membrane, 6-Middle connecting washer, 61-Middle connecting ring, 62-Upper annular groove, 7-Circular ring, 8-Snap fastener. Detailed Implementation

[0037] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0038] See Figures 1 to 7 This utility model discloses an individual respirable dust sampling flow calibration connection device. The individual respirable dust sampling flow calibration connection device mainly includes an upper sleeve 1, a connecting sleeve 2, a lower sleeve 3, a circular washer 4, a circular filter membrane 5, a middle connecting washer 6, a circular ring 7, and a buckle 8. The components work together to achieve a stable connection and accurate calibration between the individual respirable dust sampling device and the flow calibration device.

[0039] The structure and connection relationships of the components of this device are as follows:

[0040] Upper connecting sleeve 1: Serving as the upper connecting base of the device, its interior is sequentially formed from top to bottom with an upper connecting groove 11, a middle connecting groove 12, and an upper fixing groove 13. All three are circular with progressively increasing diameters. This stepped groove design provides precise positioning space for the installation of the connecting sleeve 2. An upper connecting tube 14 extends vertically upward from the top of the upper connecting sleeve 1. The upper connecting tube 14 is used to connect with the sampling equipment, providing a channel for airflow into the device. An annular groove 121 is formed on the edge of the top groove surface of the middle connecting groove 12, used to embed the middle connecting ring 61 of the middle connecting washer 6, enhancing sealing performance. The inner wall of the upper fixing groove 13 has a fixing internal thread 131, enabling a detachable connection with the connecting sleeve 2 through threaded engagement. A buckle 8 is installed on the outer side of the middle connecting groove 12, which can fix the entire device to the operator's work clothes (such as the edge of a pocket, collar, etc.), avoiding fatigue and shaking caused by holding the device during calibration, and improving operational stability.

[0041] Connecting sleeve 2: This core component connects the upper connecting sleeve 1 and the lower connecting sleeve 3. Its upper part is integrally formed with an upper connecting ring 21 and an upper fixing ring 22. The outer wall of the upper fixing ring 22 has a fixing external thread 221, which matches the fixing internal thread 131 of the upper connecting sleeve 1. Rotating the connecting sleeve 2 allows it to be installed into the upper fixing groove 13 of the upper connecting sleeve 1. The diameter of the upper connecting ring 21 is the same as the diameter of the middle connecting groove 12. After installation, the upper connecting ring 21 fits perfectly within the middle connecting groove 12, forming a circular gap with the top surface of the middle connecting groove 12. A middle connecting washer 6 is placed in this gap to further enhance the sealing effect. The top surface of the upper connecting ring 21 has a lower ring groove 211 with a semi-circular cross-section, which aligns and splices with the upper ring groove 62 at the bottom edge of the middle connecting washer 6, forming a complete circular cavity. A circular ring 7 is embedded in the cavity, and the elastic deformation of the circular ring 7 fills the gap, preventing air leakage. The lower inner side of the connecting sleeve 2 is provided with a circular groove 23 for placing a circular washer 4 and a circular filter membrane 5. The lower inner wall of the circular groove 23 is provided with a connecting internal thread 24 to provide a threaded interface for the installation of the lower connecting sleeve 3.

[0042] Lower connecting sleeve 3: As the lower connecting component of the device, it has a lower connecting ring 31 at its top. The outer wall of the lower connecting ring 31 has an external connecting thread 32, which mates with the internal connecting thread 24 of the connecting sleeve 2 to achieve a firm connection between the lower connecting sleeve 3 and the connecting sleeve 2. The lower part of the inner ring of the lower connecting ring 31 has a funnel-shaped conical groove 34. The conical groove 34 communicates with the lower connecting sleeve 33, which extends vertically from the bottom of the lower connecting sleeve 3. The conical groove 34 can guide the airflow smoothly into the lower connecting sleeve 33, avoiding airflow turbulence from affecting the flow calibration accuracy. The lower connecting sleeve 33 is used to dock with the flow calibration equipment to ensure stable airflow transmission during the calibration process.

[0043] The filtration and sealing assembly includes two circular gaskets 4, a circular filter membrane 5, a central gasket 6, and a circular ring 7. The circular filter membrane 5 is a special filter membrane for respirable dust sampling, and its diameter matches the diameter of the circular groove 23. It is sandwiched between the two circular gaskets 4 and placed together in the circular groove 23. The circular gaskets 4 serve two purposes: firstly, to fix the circular filter membrane 5 and prevent it from shifting; secondly, to enhance the sealing between the filter membrane and the inner wall of the circular groove 23. The central gasket 6 is made of elastic sealing material, and its edge protrudes upward to form a central ring 61. The central ring 61 is embedded in the annular groove 121 of the central groove 12, achieving a preliminary seal between the upper sleeve 1 and the connecting sleeve 2. The circular ring 7 is an elastic rubber ring placed in the annular cavity formed by the splicing of the upper ring groove 62 and the lower ring groove 211. It fills the gap with its own elasticity to form a secondary seal. The double sealing structure effectively prevents airflow leakage from the connection point.

[0044] Assembly and operation process of this device:

[0045] First, assemble the upper sleeve 1 and the connecting sleeve 2: place the intermediate washer 6 in the intermediate groove 12 of the upper sleeve 1, so that the intermediate ring 61 of the intermediate washer 6 is embedded in the annular groove 121, and then put the circular ring 7 into the upper annular groove 62 of the intermediate washer 6; then align the upper fixing ring 22 of the upper part of the connecting sleeve 2 with the upper fixing groove 13 of the upper sleeve 1, rotate the connecting sleeve 2, so that the fixing external thread 221 and the fixing internal thread 131 are engaged, until the upper connecting ring 21 is completely placed in the intermediate groove 12. At this time, the upper annular groove 62 and the lower annular groove 211 are aligned, and the circular ring 7 is tightly wrapped in the annular cavity, completing the sealing connection between the upper sleeve 1 and the connecting sleeve 2.

[0046] Next, install the filter assembly: place a circular washer 4 into the circular groove 23 of the connecting sleeve 2, then lay the circular filter membrane 5 flat on top of the circular washer 4, and finally cover the circular filter membrane 5 with another circular washer 4 to ensure that the circular filter membrane 5 is completely clamped and fixed.

[0047] Finally, assemble the lower connecting sleeve 3: align the lower connecting ring 31 at the top of the lower connecting sleeve 3 with the lower part of the placement groove 23 of the connecting sleeve 2, rotate the lower connecting sleeve 3 to make the connecting external thread 32 engage with the connecting internal thread 24, until the lower connecting ring 31 fits against the bottom of the connecting sleeve 2, and complete the assembly of the entire device.

[0048] The working process of this device:

[0049] Preparation before calibration: Secure the assembled device to the worker's work clothes using the buckle 8 on the side of the middle connecting slot 12 to ensure the device is in a stable position; connect the upper connecting sleeve 14 of the upper connecting sleeve 1 to the air outlet of the individual respirable dust sampling device, and connect the lower connecting sleeve 33 of the lower connecting sleeve 3 to the air inlet of the flow calibration device. Check that all connections are secure and that there is no looseness.

[0050] Flow calibration: Start the sampling device and flow calibration device. The airflow generated by the sampling device passes through the upper connecting sleeve 14 and enters the upper connecting groove 11 of the upper connecting sleeve 1. Then it flows through the middle connecting groove 12 and the inside of the connecting sleeve 2, and passes through the circular washer 4 and the circular filter membrane 5. The filter membrane simulates the actual sampling environment to filter the airflow. The filtered airflow passes through the conical groove 34 of the lower connecting ring 31 and smoothly enters the lower connecting sleeve 33. Finally, it flows into the flow calibration device, which detects and calibrates the airflow.

[0051] Post-calibration operation: After calibration, turn off the sampling device and the flow calibration device. First, disconnect the upper sleeve 14 from the sampling device and the lower sleeve 33 from the calibration device. Then, remove the device using the clip 8. If the filter membrane needs to be replaced, rotate to remove the lower sleeve 3. Take out the used circular gasket 4 and the circular filter membrane 5 in sequence. Replace the filter membrane and gasket according to the installation steps. After reassembly, the next calibration operation can be performed.

[0052] This embodiment, through reasonable structural design and sealing scheme, ensures the compatibility, sealing performance and ease of operation of the device, which can be effectively adapted to different types of sampling and calibration equipment, ensuring the accuracy and stability of individual respirable dust sampling flow calibration, and is suitable for on-site calibration scenarios in various workplaces.

[0053] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A device for calibrating the flow rate of individual respirable dust sampling, characterized in that, include: Upper sleeve (1), connecting sleeve (2) and lower sleeve (3); The upper sleeve (1) is provided with an upper connecting groove (11), a middle connecting groove (12) and an upper fixing groove (13) from top to bottom. The upper connecting groove (11), the middle connecting groove (12) and the upper fixing groove (13) are all circular and their diameters increase sequentially. The upper part of the connecting sleeve (2) is provided with an upper connecting ring (21) and an upper fixing ring (22). The outer wall of the upper fixing ring (22) is provided with a fixing external thread (221), and the inner wall of the upper fixing groove (13) is provided with a matching fixing internal thread (131). The connecting sleeve (2) is installed in the upper connecting sleeve (1) by threaded connection. The diameter of the upper connecting ring (21) is the same as the diameter of the middle connecting groove (12). The upper connecting ring (21) is placed in the middle connecting groove (12). The lower inner side of the connecting sleeve (2) is provided with a circular groove (23), and two circular washers (4) and a circular filter membrane (5) are arranged in sequence in the circular groove (23). The circular filter membrane (5) is sandwiched between the two circular washers (4). The lower part of the storage groove (23) is provided with a connecting internal thread (24), the top of the lower connecting sleeve (3) is provided with a lower connecting ring (31), the outer wall of the lower connecting ring (31) is provided with a connecting external thread (32) that matches the connecting internal thread (24), and the lower connecting sleeve (3) is installed at the bottom of the connecting sleeve (2) by a threaded connection. The upper sleeve (1) has an upper connecting tube (14) extending vertically upward from the top, and the lower sleeve (3) has a lower connecting tube (33) extending vertically downward from the bottom.

2. The individual respirable dust sampling flow rate calibration connection device according to claim 1, characterized in that, A circular gap is formed between the upper connecting ring (21) and the top groove surface of the middle connecting groove (12), and a middle connecting washer (6) is provided in the circular gap; The top groove edge of the central groove (12) is provided with an annular groove (121), and the edge of the central washer (6) protrudes upward to form a central ring (61), which is embedded in the annular groove (121). The bottom edge of the intermediate washer (6) is provided with an upper ring groove (62) with a semi-circular cross section, and the top surface of the upper connecting ring (21) is provided with a matching lower ring groove (211) with a semi-circular cross section. The upper ring groove (62) and the lower ring groove (211) are aligned and spliced ​​to form a circular cavity, and a circular ring (7) is provided inside the circular cavity.

3. The individual respirable dust sampling flow rate calibration connection device according to claim 1, characterized in that, The lower part of the inner ring of the lower connecting ring (31) is a funnel-shaped conical groove (34) and is connected to the lower connecting sleeve (33).

4. The individual respirable dust sampling flow rate calibration connection device according to claim 1, characterized in that, The outer wall side of the central groove (12) is provided with a buckle (8) for fixing the device to clothing.

5. The individual respirable dust sampling flow rate calibration connection device according to claim 1, characterized in that, The upper connecting sleeve (14) and the lower connecting sleeve (33) are used to connect the sampling equipment and the flow calibration equipment, respectively.

6. The individual respirable dust sampling flow rate calibration connection device according to claim 1, characterized in that, The circular filter membrane (5) is a filter membrane for sampling respirable dust, and its diameter matches the diameter of the circular groove (23).

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