Anti-pollution cleanable negative pressure dosing chamber for inhalation preparation

Abstract

The invention discloses an inhalation preparation anti-pollution cleanable negative pressure dosing chamber which comprises a negative pressure dosing chamber body, and a laminar flow cover and an air supply pipeline are arranged above the negative pressure dosing chamber body. An exhaust pore plate is arranged on the ground of the negative-pressure dosing chamber, and a ground exhaust cavity is arranged below the negative-pressure dosing chamber; an air return pipeline is arranged outside the negative pressure dosing chamber, one end of the air return pipeline is communicated with the ground exhaust cavity, a filter is embedded in the air return pipeline, and the other end of the air return pipeline is connected with an exhaust device; a water spraying device is further arranged in the negative-pressure dosing chamber and used for cleaning the negative-pressure dosing chamber or injecting water to the bottom of the negative-pressure dosing chamber, and the ground exhaust cavity is provided with a controllable water outlet; through the arrangement, the influence on the distribution of an inhaled preparation in a local space due to non-uniform flowing direction of the gas when the gas returns to the air pipe near the ground can be avoided, the interference on the flowing direction of the return air due to the standing angle of a person is avoided, and the consistency of the dosing process is ensured; in addition, targeted effective cleaning can be achieved according to the sedimentation characteristic of the inhaled preparation, and pollution is prevented.

Description

Technical Field

[0001] The invention belongs to the technical field of drug administration environment for medical clinical trials, and relates to a negative pressure drug administration chamber, in particular to a negative pressure drug administration chamber which is pollution-proof and cleanable for inhalation preparations. Background Art

[0002] When conducting pharmacokinetic or bioequivalence studies on new drugs that are administered by inhalation, a certain number of subjects need to be administered the drug. Due to the special administration method of this type of preparation, after administration, some of the drug will remain in the local space in the form of aerogels or small particles in the air; when the next subject enters this space, this part of the residual drug will contaminate the newly inhaled drug, resulting in inaccurate research results. In order to prevent unverified drugs from leaking into spaces outside the experimental environment, or to prevent viruses from leaking when patients carrying pathogens are tested, the test environment should be in a negative pressure state. In addition, the ambient temperature and humidity of the drug administration environment will also affect the absorption of the drug by the subject's nasal mucosa. In order to study the durability of the drug efficacy in different climatic environments, the temperature and humidity in the drug administration chamber need to be relatively accurate.

[0003] CN110433365B discloses a negative pressure medication room for inhalation preparations to prevent contamination. Two groups of laminar flow formation areas are installed in the walls on both sides of the room to form a horizontal laminar flow, and a rotatable medication area is set in the middle of the two groups of laminar flow formation areas. The gas is blown into the room from the laminar flow formation area on one side and then discharged from the other laminar flow area; the laminar flow formation areas on both sides are respectively provided with a refrigeration device and a heating device, which is convenient for regulating the room temperature after cooling or heating the gas. The standing position of the subject can be freely adjusted according to the direction of gas flow. The above-mentioned involves achieving the purpose of providing a single-direction airflow in the medication room; at the same time, the matrix blowing structure installed in the walls on both sides can meet the needs of different laminar flow speeds and different temperature requirements. However, this design still has problems when used: (1) The spoilers in the matrix-type blowing structure installed on the walls on both sides have limited effect on the uniformity of the airflow, and the accessories are numerous and small, making it difficult to add abnormal feedback signals one by one. When local accessories are abnormal, the airflow is greatly affected; (2) The single horizontal airflow is affected by the human body position, the placement of the equipment, etc., and requires high compliance from the subjects. It is difficult to manage when the number of tests is large; (3) The room structure is large, and there are many dead corners on the side facades of the room, which are difficult to clean. Residual drugs after long-term use will cause cross-contamination.

[0004] CN210872658U discloses a negative pressure medication room with vertical airflow. After the gas enters the room through a high-efficiency filter, it is discharged from the outlet above one side wall; CN219711107U discloses a negative pressure air supply method with upward delivery and upward return, and its return air outlet is behind the side of the subject's chair. These two patents propose the use of vertical airflow-side wall return air as the ventilation method of negative pressure medication room. Although this method is commonly used in clean rooms, it is not suitable for working environments that are sensitive to airflow disturbances.

[0005] CN214232337U proposes a treatment plan for drug-containing colloids or fine drug particles trapped in the air of the negative pressure medication room, which uses circulating water spraying to clean the air and exhausts the air in the same ventilation chamber through an exhaust fan. This solution replaces the filter filtration method with a water wash method, which reduces the cost of polluted air discharge treatment in the room to a certain extent. However, the water wash pipe and the return air pipe are in the same cavity, and the splashing water is easily sucked back into the exhaust equipment, causing pollution and damage to the equipment; and the return air flow is large and difficult to clean thoroughly. Using this circulating air in the room will cause the air to be polluted, and the subject experience is not good. Summary of the invention

[0006] The purpose of the present invention is to improve the existing negative pressure medication room in view of several specific usage requirements of the current negative pressure medication room (negative pressure, closure, single-direction airflow to prevent disturbance, controllable temperature and humidity, return air treatment, and room cleaning). While ensuring that the negative pressure medication room can provide pure single-direction airflow and ensure the consistency of the medication process for the convenience of experiments, it can also facilitate the thorough cleaning of the medication room and return air, thereby avoiding short-term and long-term cross-contamination of drugs by experimenters.

[0007] The technical solution adopted by the present invention is as follows: A contamination-proof and cleanable negative pressure drug delivery chamber for inhalation preparations, comprising: A negative pressure medication room, above which a laminar flow hood and an air supply duct connected to the laminar flow hood are provided; The floor of the negative pressure medication room adopts an exhaust plate with uniform holes, and a floor exhaust cavity is provided under the negative pressure medication room; A return air duct is provided outside the negative pressure medication room and is airtightly isolated from the negative pressure medication room. One end of the return air duct is connected to the ground exhaust cavity. A filter is embedded in the return air duct. The other end of the return air duct is connected to an exhaust device for exhausting air to the outside. A water spraying device is also provided in the negative pressure medication chamber for cleaning the negative pressure medication chamber or injecting water into the bottom, and the ground exhaust cavity has a controllable drain port; Fresh air is delivered into the laminar flow hood through the air supply duct, enters the negative pressure medication chamber after filtering and pressure equalization to form a vertically downward stable laminar flow zone, enters the ground exhaust cavity through the exhaust orifice plate, and then enters the return air duct, and is discharged by the exhaust device after passing through the filter.

[0008] In the above technical solution, further, the negative pressure medication chamber has two different working modes according to the sedimentation characteristics of the inhalation preparation: 1) When the inhalation preparation used is not easy to form aerogel or can settle freely, the inhalation preparation remaining in the air is blown to the bottom of the exhaust hole plate by the stable laminar flow vertically downward from the top, and after the administration is completed, the water spraying device is turned on for cleaning, and the drugs remaining in the exhaust hole plate and the ground exhaust cavity are cleaned and processed; 2) When the inhalation preparation used is not easy to settle or is easily lifted up by air flow fluctuations, the water spraying device should be turned on before administration to inject water under the exhaust hole plate to allow the ground exhaust cavity to accumulate water. The inhalation preparation remaining in the air will be brought under the exhaust hole plate by the stable laminar flow vertically downward from the top, and will come into contact with the water surface in the ground exhaust cavity, where it will be adsorbed on the water surface and no longer lifted up, thereby improving the efficiency of the return air purification treatment and reducing the contamination of subsequent administration by the inhalation preparation.

[0009] Furthermore, the laminar flow hood includes a polyester membrane, a plate-type medium-efficiency filter layer, a sub-high-efficiency filter layer or a high-efficiency filter layer, and a polyester membrane pressure-equalizing layer, which are arranged in sequence from top to bottom.

[0010] Furthermore, the bottom surface of the ground exhaust cavity is a waterproof slope with an inclined angle, and the lowest end of the slope is the connection end with the return air duct, and the controllable drain outlet is arranged at the lowest point of the slope.

[0011] Furthermore, the filter is located at least 20 centimeters higher than the exhaust hole plate.

[0012] Furthermore, the filter is a pull-out, easily replaceable filter box embedded in the return air duct. When embedded in place, the return air duct is in a sealed state. A pressure sensor is provided in the return air duct to monitor the sealing effect of the pull-out, easily replaceable filter box.

[0013] Furthermore, a buffer chamber is provided outside the negative pressure medication chamber, and the air pressure in the buffer chamber is higher than the negative pressure medication chamber and lower than the atmospheric pressure.

[0014] Furthermore, a water level detector is provided between the ground exhaust cavity and the exhaust hole plate.

[0015] Furthermore, one end of the air supply duct away from the laminar flow hood is connected to an air supply air conditioner and a polyester isolation hood in sequence, and one end of the exhaust device away from the return air duct is connected to a check valve.

[0016] Furthermore, the negative pressure medication chamber has a door that opens from the inside to the outside or a sliding closed door.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects: (1) By installing an exhaust hole plate on the ground, the laminar flow in the dosing room remains vertical near the ground, so that the airflow in the room is not affected by the movement of the subjects or the placement of other devices, which can ensure the consistency of the dosing process and improve the subject compliance and durability of the experiment of negative pressure administration of inhaled preparations; (2) By setting a ground exhaust cavity under the exhaust hole plate, a water storage function can be achieved. In particular, the bottom surface is set as a waterproof slope, which can further increase the contact area between the gas carrying the drug and the water. The residual drug can be washed away by water at the moment of airflow contact, avoiding the cross-contamination caused by the secondary lifting of the airflow after the drug remains in the dead corner of the room. It can also remove the drug residue in the air to the maximum extent, reduce the filter pressure, and reduce the drug residue in the return air duct. (3) By setting up the exhaust hole plate and the ground exhaust cavity below, the indoor water-washable function is realized. The room side walls and ground holes can be easily washed through the indoor water spraying device. The cleaning process is convenient, the indoor drug residue is minimized to the greatest extent, and the long-term use stability is good; the water spraying device can be controlled manually or by an electronic valve. It can be moved by hand or sprayed at multiple fixed points. The drainage operation is convenient; the waterproof slope design of the ground exhaust cavity can quickly drain water to avoid residue;

[0018] (4) By installing a filter in the return air duct, especially a pull-out, easy-to-replace filter box, the return air (exhaust gas) treatment device can be easily monitored and replaced according to experimental requirements, ensuring that untested drugs do not leak into the space outside the experiment, which is beneficial to environmental protection requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the front view of the single negative pressure medication chamber.

[0020] Figure 2 This is a top view of the side of a single negative pressure medication chamber.

[0021] Figure 3 This is the layout diagram of a room with two negative pressure medication chambers.

[0022] Figure 4 This is a room layout diagram containing 3 negative pressure medication chambers.

[0023] Figure numbers: 1-sealed window; 2-airtight door; 3-return air duct; 4-easy-to-replace filter box; 5-exhaust orifice plate; 6-metal column; 7-controllable drain outlet; 8-PLC controller and display screen; 9-door interlock display; 10-exterior facade wall; 11-waterproof slope; 12-air supply air conditioner; 13-air supply duct; 14-laminar flow hood; 15-polyester membrane; 16-plate medium efficiency filter layer; 17-sub-high efficiency filter layer or high efficiency filter layer; 18-polyester membrane equalizing layer; 19-check valve; 20-exhaust device; 21-polyester isolation cover; 22-indoor light strip; 23-gas flow direction diagram; 24-subject and equipment diagram; 25-water spraying device; 26-transfer window. DETAILED DESCRIPTION

[0024] The present invention is further described below in conjunction with specific embodiments, and the specific embodiments and descriptions of the present invention are used to explain the technical solution of the present invention, but are not intended to limit the present invention. It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other.

[0025] According to an embodiment of the present invention, the anti-pollution and cleanable negative pressure dosing chamber (also referred to as a negative pressure dosing chamber) for inhalation preparations of the present invention mainly includes a negative pressure dosing chamber, above which a laminar flow hood 14 and an air supply duct 13 connected to the laminar flow hood 14 are arranged; the floor of the negative pressure dosing chamber adopts an exhaust orifice plate 5 with uniform holes, and a ground exhaust cavity is arranged below the negative pressure dosing chamber; outside the negative pressure dosing chamber, a return air duct 3 is arranged which is airtightly isolated from the negative pressure dosing chamber, one end of the return air duct 3 is connected to the ground exhaust cavity, a filter is embedded in the return air duct, and the other end of the return air duct is connected to an exhaust device 20 for exhausting air to the outside; a water spraying device 25 is also arranged in the negative pressure dosing chamber for cleaning the negative pressure dosing chamber or injecting water into the bottom, and the ground exhaust cavity has a controllable drain port 7. This setting can not only effectively ensure the stability and anti-interference ability of the vertical airflow and guarantee the consistency of the experiment, but also can effectively clean the inhalation preparation according to the sedimentation characteristics to prevent pollution: when the experimental inhalation preparation is not easy to form aerogel and can settle freely, the gas vertically downward from the top will blow the remaining preparation in the air to the exhaust hole plate. After the experiment, the exhaust hole plate and the residual drugs in the ground exhaust cavity are cleaned and treated by water washing; when the experimental inhalation preparation is light and easy to be lifted up by air flow fluctuations, water is injected under the exhaust hole plate before the experiment to store water in the ground exhaust cavity. The residual preparation in the air is brought into the large water surface under the hole plate by the airflow, adsorbed on the water surface, and no longer lifted up, which improves the efficiency of the return air purification treatment and effectively reduces the pollution of drugs in the air to the next subject.

[0026] In some embodiments of the present invention, the laminar flow hood 14 includes a polyester membrane 15, a plate-type medium-efficiency filter layer 16, a sub-high-efficiency filter layer or a high-efficiency filter layer 17, and a polyester membrane pressure-equalizing layer 18, which are arranged in sequence from top to bottom. Above the negative pressure medication chamber, the gas (fresh air) is fed in by the air supply duct 3 of the air purification system, and after preliminary filtration by the polyester membrane, it passes through the plate-type medium-efficiency filter layer, the (sub) high-efficiency filter layer, and the polyester membrane pressure-equalizing layer in the laminar flow hood, and then blows into the negative pressure medication chamber, forming a uniform laminar flow zone from top to bottom. Among them, the gas is initially filtered through the polyester isolation cover 21 at the outer end of the air supply duct to remove large particles of dust, sand, lint and other dirt in the air, and isolate them outside the air supply air conditioner 12; after passing through the polyester membrane 15, the gas is filtered through two rounds of plate-type medium-efficiency filter layer and sub-high-efficiency filter layer (or high-efficiency filter layer) to obtain clean air with controllable particle size in the gas; after the clean air passes through the polyester membrane equalizing layer, the wind speed is further reduced, and due to the setting of the exhaust hole plate 5 and the ground exhaust cavity, the gas flows in a vertical direction and spreads evenly, and forms a laminar flow zone downward; this design can especially make the gas flow in the direction close to the ground still in a vertical direction, without being disturbed by the movement of personnel and the placement of equipment, so that the consistency of personnel being tested at any position in the room is good, thereby improving the compliance of the subjects and the durability of the experimental method.

[0027] In some embodiments of the present invention, the bottom surface of the ground exhaust cavity is a waterproof slope 11 with an inclined angle, and the lowest end of the slope is the connection end with the return air duct 3, and the controllable drain outlet 7 is arranged at the lowest point of the slope.

[0028] In some embodiments of the present invention, the filter is located at least 20 centimeters higher than the exhaust orifice plate.

[0029] In some embodiments of the present invention, the filter is a pull-out, easily replaceable filter box 4 embedded in the return air duct, in which filter material is placed. When embedded in place, the return air duct is in a sealed state, and a pressure sensor is provided in the return air duct to monitor the sealing effect of the pull-out, easily replaceable filter box. The setting of the filter can effectively absorb moisture and other pollutants in the return air, ensure that the exhaust reaches acceptable indicators, and reduce pollution to the environment.

[0030] In some embodiments of the present invention, the negative pressure medication chamber can be a single body, or multiple negative pressure medication chambers can be arranged adjacent to each other and share part of the space. The negative pressure medication chamber can be a buffer chamber, and the air pressure in the buffer chamber is higher than the negative pressure medication chamber and lower than the atmospheric pressure.

[0031] In some embodiments of the present invention, all controls can be manual controls or centralized automatic controls. A PLC controller and a display screen 8 can be provided.

[0032] In some embodiments of the present invention, a colored indoor light strip 22 is provided in the negative pressure medication chamber to instruct the subject to wait, accept medication, end medication, etc., and voice prompts can be provided synchronously to provide convenience for hearing-impaired subjects.

[0033] In some embodiments of the present invention, a PLC control panel is provided on the outer wall of the negative pressure medication room to control the opening of the room, or the linkage between the negative pressure medication room and the buffer room door, the indoor temperature, the indoor humidity, and the color of the indoor light strip; In some embodiments of the present invention, a sealed window may be provided at the door of the negative pressure medication room for explaining the test operation to the subjects and observing the experimental process; monitoring facilities may also be placed inside the room and real-time observation may be performed on the PLC monitor.

[0034] In some embodiments of the present invention, the temperature and humidity of the negative pressure medication chamber are controlled by the air conditioner at the air supply end to achieve heating, cooling, humidification and dehumidification.

[0035] In some embodiments of the present invention, a gas flow meter may be provided at the air supply air conditioner and the exhaust device to provide feedback on the airtightness of the exhaust passage.

[0036] In some embodiments of the present invention, the exhaust hole plate on the waterproof slope is made of stainless steel, and the exhaust hole plate is placed in a horizontal direction; the exhaust hole plate and the waterproof slope are connected and fixed by a metal material.

[0037] In some embodiments of the present invention, the exhaust orifice plate is connected to the inclined surface via a metal column 6; or via a partition plate parallel to the flow direction of the gas under the exhaust orifice plate.

[0038] In some embodiments of the present invention, a transfer window 26 may be provided on the side wall of the negative pressure medication room for transferring special articles or drugs in and out. Furthermore, a glove box may be embedded in the transfer window.

[0039] Example 1

[0040] like Figure 1 , Figure 2 The figure shows a schematic diagram of a single negative pressure medication chamber.

[0041] The negative pressure medication chamber is located outside the single negative pressure medication chamber, and mainly includes a closed window 1 (for observing the room), an airtight door 2 (manually opened from the inside to the outside, with a door interlocking display, and this door is closed when the outer door of the buffer chamber is opened), a return air duct 3, an easily replaceable filter box 4 embedded in the return air duct (which can be filled with activated carbon or filter material), 7-a drainage valve connected to the drainage point, and an external facade wall 10 (made of stainless steel, brick wall or clean board), which plays a partition role. The PLC controller and display screen are embedded in the external facade wall to control the indoor temperature, humidity, light strip-medication system linkage, drainage, and monitor the indoor air pressure, airflow, and air pressure in the air duct. Indoor air is sucked in from the outside by the air supply air conditioner 12, filtered through the polyester isolation cover 21 to remove sand, lint, dust, etc. in the air, and then discharged through the air supply duct 13, and deeply filtered through the polyester membrane 15 in the laminar flow cover 14, the plate-type medium-efficiency filter layer 16 in the laminar flow cover, and the plate-type sub-high-efficiency filter layer 17 in the laminar flow cover to remove particles and bacteria in the air, and finally decompressed through the polyester membrane equalizing layer 18 and evenly discharged into the negative pressure room, forming a vertical downward air flow. The flow direction of the gas in the room is as follows: Figure 2 As shown by the arrow 23, the air flow blows from top to bottom into the cavity below the exhaust hole plate 5 on the ground (i.e., the ground exhaust cavity), and flows along the waterproof slope 11 in the ground exhaust cavity to the return air port at the lower end of the return air duct 3, and then passes through the pull-out easy-to-replace filter box 4 to remove moisture, odor, and possible residual drugs in the air, and is discharged to a suitable location through the exhaust device 20. There is a check valve 19 at the end of the exhaust device to prevent external gas from entering the negative pressure medication chamber system to ensure the maintenance of indoor negative pressure.

[0042] Before dosing, after guidance and adaptation in the buffer room, the subject opens the door and enters the room. The indicator light in the room shows yellow (ready), and the subject moves to the designated position. When the room pressure is normal, the airflow is stable, and the subject is ready, the dosing device is turned on, and the room indicator light turns red (in progress, do not move). At the end of the experiment, the room indicator light turns green, and the subject can move freely in the room or leave the room.

[0043] During medication, in the negative pressure medication room, the gas is blown vertically from the uniform exhaust hole plate on the floor of the negative pressure medication room to the floor exhaust cavity. This design ensures that the gas flow in the direction close to the ground remains vertical and is not affected by the movement of personnel and the placement of equipment, so that personnel can be tested consistently at any position in the room, thereby improving the compliance of the subjects and the durability of the experimental methods.

[0044] The side wall of the negative pressure medication room is connected to a water pipe (purified water or tap water can be selected as required), and the end of the pipe is a portable water spraying device, which is used to thoroughly clean the negative pressure medication room and fill the bottom with water. When the experimental inhalation preparation is not easy to form aerogel and can settle freely, the gas vertically downward from the top blows the remaining preparation in the air to the bottom of the exhaust orifice plate. After the experiment, the residual drugs on the exhaust orifice plate and the bottom inclined surface are cleaned and processed by water washing. When the experimental inhalation preparation is light and easily lifted by air flow fluctuations, water is injected under the bottom exhaust orifice plate before the experiment, and the valve at the controllable drain port 7 is closed. The residual preparation in the air is brought into the large area of ​​water surface under the exhaust orifice plate by the airflow, adsorbed on the water surface, and no longer lifted. While improving the efficiency of the return air purification treatment, it can reduce the contamination of the drugs in the air to the next subject. The lower part of the waterproof slope in the exhaust cavity on the floor of the negative pressure medication room is connected to the return air duct, and the lowest part of the slope is connected to a controllable drain (discharging water to, for example, a laboratory sewage drain or a collection bucket) for discharging sewage generated by room cleaning. This valve is integrated into the PLC for control. A water level detector is set on the metal column 6 under the exhaust orifice plate. When the water level exceeds 5 cm below the exhaust orifice plate, the switch of the indoor water point, i.e., the water spraying device 25, is automatically closed, and a warning icon is displayed on the PLC.

[0045] The easily replaceable filter box 4 is provided on the return air duct, and activated carbon is placed inside to absorb moisture and other pollutants in the return air, ensuring that the exhaust air reaches acceptable indicators and reduces pollution to the surrounding environment. The height of the filter box is at least 20 cm higher than the height of the exhaust hole plate on the ground, which is convenient for pulling out and replacing the filter material; it is sealed when closed, and a pressure sensor is provided in the air duct to monitor the sealing effect here.

[0046] Example 2

[0047] On the basis of Example 1, the air supply air conditioner 12 is a large air volume and low noise fan, and the air outlet wind speed is 3-5 m / s. The plate-type medium efficiency filter layer 16 filter in the laminar flow hood 14 has a filtration effect of ≥0.5 μm of 99.99%. The facade wall 10 is made of 304 stainless steel; the exhaust orifice plate 5 is made of stainless steel. The room lighting is 300 lux fluorescent lamps, and the ceiling is equipped with yellow light lamps, ultraviolet lamps, and fluorescent lamps.

[0048] Example 3

[0049] On the basis of embodiment 1, a transfer window 26 is embedded on one side of the wall, and a glove box can be set in the transfer window 26 to facilitate the transfer of special items or drugs. The transfer window can be on the lower side, side, or other wall of the negative pressure room of the sealing window.

[0050] Example 4

[0051] like Figure 3The figure shows a plan view of a negative pressure medication room with two single negative pressure medication chambers. As shown in the figure, when two negative pressure medication rooms are needed, the two rooms share a buffer room, exhaust system, PLC control panel, and drainage system; each room uses a separate air supply system to regulate the indoor and outdoor pressure difference. The two rooms are interlocked with the outer door of the buffer room to ensure the stability of the pressure in the negative pressure medication room.

[0052] Example 5

[0053] On the basis of Example 3, the pressure inside the negative pressure medication chamber is -20Pa, and the pressure outside the negative pressure medication chamber is -5Pa.

[0054] Example 6

[0055] like Figure 4 The figure shows a plan view of a negative pressure medication room that includes three single negative pressure medication chambers. As shown in the figure, when three rooms for negative pressure medication are needed, the three rooms share a buffer room and a PLC control system; two adjacent rooms share an exhaust system and a drainage system; each room uses a separate air supply system to regulate the indoor and outdoor pressure difference. The three rooms are interlocked with the outer doors of the buffer room to ensure that the pressure in the negative pressure medication room is stable. For rooms with narrow aisles, a horizontal airtight door design is adopted to save space to the maximum extent and ensure that the relative spatial layout of the three rooms is consistent.

[0056] The above description is only for illustrative purposes, and those skilled in the art may modify and re-combine the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A contamination-proof and cleanable negative pressure drug delivery chamber for inhalation preparations, characterized in that: include: A negative pressure medication room, above which a laminar flow hood and an air supply duct connected to the laminar flow hood are provided; The floor of the negative pressure medication room adopts an exhaust plate with uniform holes, and a floor exhaust cavity is provided under the negative pressure medication room; A return air duct is provided outside the negative pressure medication room and is airtightly isolated from the negative pressure medication room. One end of the return air duct is connected to the ground exhaust cavity. A filter is embedded in the return air duct. The other end of the return air duct is connected to an exhaust device for exhausting air to the outside. A water spraying device is also provided in the negative pressure medication chamber for cleaning the negative pressure medication chamber or injecting water into the bottom, and the ground exhaust cavity has a controllable drain port; Fresh air is delivered into the laminar flow hood through the air supply duct, enters the negative pressure medication chamber after filtering and pressure equalization to form a vertically downward stable laminar flow zone, enters the ground exhaust cavity through the exhaust orifice plate, and then enters the return air duct, and is discharged by the exhaust device after passing through the filter.

2. The anti-pollution and cleanable negative pressure drug delivery chamber for inhalation preparations according to claim 1, characterized in that: The negative pressure drug delivery chamber has two different working modes according to the sedimentation characteristics of the inhalation preparation: 1) When the inhalation preparation used is not easy to form aerogel or can settle freely, the inhalation preparation remaining in the air is blown to the bottom of the exhaust hole plate by the stable laminar flow vertically downward from the top, and after the administration is completed, the water spraying device is turned on for cleaning, and the drugs remaining in the exhaust hole plate and the ground exhaust cavity are cleaned and processed; 2) When the inhalation preparation used is not easy to settle or is easily lifted up by air flow fluctuations, the water spraying device should be turned on before administration to inject water under the exhaust hole plate to allow the ground exhaust cavity to accumulate water. The inhalation preparation remaining in the air will be brought under the exhaust hole plate by the stable laminar flow vertically downward from the top, and will come into contact with the water surface in the ground exhaust cavity, where it will be adsorbed on the water surface and no longer lifted up, thereby improving the efficiency of the return air purification treatment and reducing the contamination of subsequent administration by the inhalation preparation.

3. The anti-pollution and cleanable negative pressure drug delivery chamber for inhalation preparations according to claim 1, characterized in that: The laminar flow hood comprises a polyester membrane, a plate-type medium-efficiency filter layer, a sub-high-efficiency filter layer or a high-efficiency filter layer, and a polyester membrane pressure-equalizing layer which are arranged in sequence from top to bottom.

4. The anti-pollution and cleanable negative pressure drug delivery chamber for inhalation preparations according to claim 1, characterized in that: The bottom surface of the ground exhaust cavity is a waterproof slope with an inclined angle, and the lowest end of the slope is the end connected to the return air duct, and the controllable drain port is arranged at the lowest point of the slope.

5. The anti-pollution and cleanable negative pressure drug delivery chamber for inhalation preparations according to claim 1, characterized in that: The filter is located at least 20 centimeters higher than the exhaust hole plate.

6. The anti-pollution and cleanable negative pressure drug delivery chamber for inhalation preparations according to claim 1, characterized in that: The filter is a pull-out, easily replaceable filter box embedded in the return air duct. When embedded in place, the return air duct is in a sealed state. A pressure sensor is provided in the return air duct to monitor the sealing effect of the pull-out, easily replaceable filter box.

7. The anti-pollution and cleanable negative pressure drug delivery chamber for inhalation preparations according to claim 1, characterized in that: A buffer chamber is arranged outside the negative pressure medication chamber, and the air pressure in the buffer chamber is higher than that of the negative pressure medication chamber and lower than the atmospheric pressure.

8. The anti-pollution and cleanable negative pressure drug delivery chamber for inhalation preparations according to claim 1, characterized in that: A water level detector is provided between the ground exhaust cavity and the exhaust hole plate.

9. The anti-pollution and cleanable negative pressure drug delivery chamber for inhalation preparations according to claim 1, characterized in that: One end of the air supply duct away from the laminar flow hood is connected with an air supply air conditioner and a polyester isolation hood in sequence, and one end of the exhaust device away from the return air duct is connected with a check valve.

10. The anti-pollution and cleanable negative pressure drug delivery chamber for inhalation preparations according to claim 1, characterized in that: The negative pressure medication room is a door that opens from the inside to the outside or a sliding closed door.

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