Self-filtering forced air respirator

Abstract

The application discloses a self-filtering forced air supply respirator and belongs to the technical field of respiratory protection equipment. The respirator comprises a face mask, an air guide pipe, an air supply box, a waist belt and a filter assembly. A fan is arranged in the air supply box. The face mask is communicated with the air outlet of the air supply box through the air guide pipe. The annular baffle is arranged in rotation in the shell. The shell is uniformly divided into multiple independent filter chambers by multiple partition plates. The through port of the annular baffle is communicated with only a single chamber. The annular baffle is driven by the rotation mechanism to rotate automatically when the filter core is blocked and the air pressure is increased, so that the through port is switched to another chamber and the corresponding filter core is started, the multiple filter cores are started and switched one by one, the filter core life is not wasted, the effective filtering capacity of each filter core is fully utilized, and the continuous protection time of the respirator is greatly prolonged.

Description

Technical Field

[0001] This invention relates to a respirator, and more particularly to a self-filtering forced-air respirator, belonging to the technical field of respiratory protection equipment. Background Technology

[0002] Forced air-purifying respirators are a type of respiratory protective equipment that uses an electric fan to purify outside air through a filter element and then deliver it into the mask for the user to breathe. In order to improve protective performance and extend service life, existing forced air-purifying respirators generally adopt a multi-filter parallel design, that is, 2-3 filter interfaces are set on the main unit, and all filters participate in the filtration operation at the same time. By increasing the total filtration area, airflow resistance is reduced, air volume is increased, and overall protection time is extended.

[0003] However, when using existing multi-filter parallel respirators, all parallel filters must be replaced simultaneously. The overall protection time of the filters is determined by the first old filter to fail. Due to the uneven distribution of pollutant concentration, the clogging and saturation rates of each filter are different, which can lead to the complete waste of the remaining lifespan of some filters. Furthermore, the respirator can only be used after all filters are assembled, which does not allow for flexible assembly of filters according to needs and limits the flexibility of the respirator.

[0004] To address these issues, a self-filtering forced-air respirator was designed. Summary of the Invention

[0005] The main objective of this invention is to provide a self-filtering forced-air respirator to solve the problems mentioned in the background art.

[0006] The objective of this invention can be achieved by adopting the following technical solution: A self-filtering forced-air respirator includes a mask, an air duct, an air supply box, a waist belt, and a filter assembly. A fan is installed inside the air supply box, and the mask is connected to the air outlet of the air supply box via the air duct. Its distinguishing feature is that: The filter assembly includes a housing, a cover plate, an annular baffle, a partition, a rotating mechanism, a mounting port, a filter element, and a sealing mechanism corresponding to each mounting port. The housing has an open end, and a cover plate is sealed and fixed to the open end; The annular baffle is coaxially rotatably installed inside the housing, and the partitions are evenly distributed circumferentially between the inner wall of the housing and the outer wall of the annular baffle, dividing the space between the housing and the annular baffle into multiple independent filter chambers. An opening is provided on the annular baffle, which can sequentially connect with different filter chambers as the annular baffle rotates. The air inlet of the fan is connected to the central area of ​​the casing; The rotating mechanism is located inside the housing. When the air pressure rises due to the blockage of the filter element corresponding to the currently open filter chamber, it drives the annular baffle to rotate, so that the opening switches to the next unused filter chamber, thereby realizing the automatic switching of filter elements one by one. The mounting port is circumferentially opened on the side wall of the housing and is connected to multiple filter chambers one by one. A filter element can be detachably installed at each mounting port. A sealing mechanism is provided at each installation port to automatically seal the installation port when no filter element is installed there.

[0007] Preferably, the rotating mechanism includes a sleeve, a first slip ring, a slide rod, a slide plate, a return spring, a second slip ring, a connecting rod, a corrugated guide groove, and a guide block; The sleeve is coaxially fixed to the inside of the cover plate, and one end of the sleeve passes through the cover plate and communicates with the outside. The first slip ring is fixedly installed inside the sleeve at the end furthest from the cover plate; The sliding rod is coaxially slidably inserted inside the sleeve. The end of the sliding rod near the cover plate extends out of the sleeve and is fixedly connected to a sliding plate. The sliding plate and the end face of the sleeve slide and seal together. The return spring is sleeved on the outside of the slide rod, and the two ends of the return spring abut against the slide plate and the first slip ring respectively; The second slip ring is coaxially disposed on the side of the first slip ring, and the second slip ring is fixedly connected to the inner wall of the annular baffle through a connecting rod; The inner wall of the second slip ring is provided with a corrugated guide groove extending in the circumferential direction, and the outer wall of the slide rod is fixed with a guide block that slides in cooperation with the corrugated guide groove.

[0008] Preferably, a limiting disc is also fixedly fitted on the outer side of the end of the sleeve away from the cover plate. The limiting disc is located between the first slip ring and the annular baffle, and the outer wall of the limiting disc slides against the inner wall of the annular baffle. Multiple first air holes are evenly distributed on the limiting plate to connect the filter chamber with the central area of ​​the shell.

[0009] Preferably, the sealing mechanism includes a fixing block, a support rod, a sleeve, a compression spring, and a second vent. The fixing block is located on the inner side of the mounting opening, and the fixing block is fixedly connected to the inner wall of the housing through the support rod; The sleeve is slidably fitted inside the installation port. The outer end of the sleeve can abut against the connector of the filter element, and the inner end of the sleeve abuts against one end of the compression spring. The other end of the compression spring abuts against the fixed block; The sleeve has a second air hole evenly opened along the circumference on its side wall.

[0010] Preferably, only one opening is opened on the annular baffle, and the number of baffles is 3 sets, which correspond to 3 independent filter chambers.

[0011] Preferably, the filter element and the installation port are connected by a threaded connection or a snap-fit ​​connection to achieve detachable installation.

[0012] Preferably, the outer end of the sleeve is provided with a sealing gasket, and the sealing gasket fits against the inner wall of the mounting port.

[0013] Preferably, a guide ring is fixed inside the housing at the end away from the cover plate, and the outer wall of the guide ring is in contact with the inner side of the annular baffle.

[0014] Preferably, the first slip ring is located at the axial centerline inside the sleeve, and reinforcing rods are uniformly provided between the outer side of the first slip ring and the inner wall of the sleeve.

[0015] Preferably, the filter element is provided in 3 sets, and the filter element 508 corresponds to 3 independent filtration chambers.

[0016] The beneficial effects of this invention are as follows: This invention provides a self-filtering forced air-supply respirator. By rotating an annular baffle inside the housing and using multiple sets of partitions to evenly divide the interior of the housing into multiple independent filter chambers, the openings on the annular baffle can communicate with only a single chamber. In conjunction with a rotating mechanism consisting of a sleeve, a first slip ring, a slide rod, a slide plate, a return spring, a second slip ring, a connecting rod, a corrugated guide groove, and a guide block, when the air pressure rises due to filter blockage, the air pressure drives the rotating mechanism to automatically rotate the annular baffle, switching the opening to another chamber and activating the corresponding filter. This enables multiple filters to be activated independently one by one and automatically switched, avoiding waste of filter life, making full use of the effective filtration capacity of each filter, and significantly extending the continuous protection time of the respirator. By configuring a sealing mechanism consisting of a fixing block, support rod, sleeve, compression spring and second air hole at the installation port, when no filter element is installed, the compression spring pushes the sleeve to block the installation port, realizing automatic sealing of the empty interface. When the filter element is installed, the filter element connector pushes the sleeve to allow the second air hole to enter the housing to conduct air passage. Single or multiple filter elements can be flexibly assembled and used without additional sealing parts, significantly improving the assembly flexibility and environmental adaptability of the respirator. Attached Figure Description

[0017] Figure 1 This is a front view of the overall structure of the present invention; Figure 2 This is a schematic cross-sectional view of the air supply box and filter assembly of the present invention; Figure 3 This is a schematic diagram of the interior of the front end of the housing of the present invention; Figure 4 This is a schematic diagram of the interior of the rear end of the housing of the present invention; Figure 5 This is an exploded view of the overall structure of the filter assembly of the present invention; Figure 6 This is a partial orthogonal sectional view of the housing of the present invention; Figure 7 This is a partial cross-sectional view of the filter assembly of the present invention; Figure 8 This is a schematic diagram showing the connection between the annular baffle and the second slip ring of the present invention; Figure 9 This is a schematic diagram of the rotating mechanism of the present invention; Figure 10 This is a schematic diagram of the corrugated guide groove of the present invention.

[0018] In the picture: 1. Mask; 2. Air tube; 3. Air supply box; 301. Fan; 4. Belt; 5. Filter assembly; 501. Housing; 502. Cover plate; 503. Annular baffle; 504. Port; 505. Partition; 506. Rotating mechanism; 5061. Sleeve; 5062. First slip ring; 5063. Sliding rod; 5064. Slide plate; 5065. Return spring; 5066. Second slip ring; 5067. Connecting rod; 5068. Corrugated guide groove; 5069. Guide block; 50610. Limiting plate; 50611. First air hole; 507. Installation port; 508. Filter element; 509. Sealing mechanism; 5091. Fixing block; 5092. Support rod; 5093. Sleeve; 5094. Compression spring; 5095. Second air hole. Detailed Implementation

[0019] To enable those skilled in the art to more clearly understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0020] Example 1: As Figures 1-10 As shown, this embodiment provides a self-filtering forced air respirator, including a mask 1, an air duct 2, an air supply box 3, a waist belt 4, and a filter assembly 5. The air supply box 3 is equipped with a fan 301, and the mask 1 is connected to the air outlet of the air supply box 3 through the air duct 2. The filter assembly 5 includes a housing 501, a cover plate 502, an annular baffle 503, a partition plate 505, a rotating mechanism 506, a mounting port 507, a filter element 508, and a sealing mechanism 509 corresponding to the mounting port 507. The housing 501 has an open end, and the cover plate 502 is sealed and fixed to the open end; An annular baffle 503 is coaxially rotatably installed inside the housing 501. Partitions 505 are evenly distributed circumferentially between the inner wall of the housing 501 and the outer wall of the annular baffle 503, dividing the space between the housing 501 and the annular baffle 503 into multiple independent filter chambers. An annular baffle 503 has an opening 504, which can sequentially connect with different filter chambers as the annular baffle 503 rotates. The air inlet of the fan 301 is connected to the central area of ​​the casing 501; The rotating mechanism 506 is located inside the housing 501. When the air pressure rises due to blockage of the filter element 508 corresponding to the currently open filter chamber, it drives the annular baffle 503 to rotate, so that the port 504 switches to the next unused filter chamber, thereby realizing the automatic switching of the filter element 508 one by one. The mounting port 507 is circumferentially opened on the side wall of the housing 501 and is connected to multiple filter chambers one by one. A filter element 508 can be detachably installed at each mounting port 507. A sealing mechanism 509 is provided at each mounting port 507 to automatically seal the mounting port 507 when no filter element 508 is installed in the mounting port 507.

[0021] In use, the user wears the air supply box 3 around their waist via the belt 4, puts on the mask 1, and starts the fan 301. The fan 301 generates negative pressure in the central area of ​​the housing 501. Outside air is first filtered and purified by the filter element 508 corresponding to the currently open filter chamber. The purified air enters the filter chamber, then enters the central area of ​​the housing 501 through the opening 504 on the annular baffle 503. Subsequently, it is drawn in and pressurized by the fan 301, and then sent to the mask 1 through the air duct 2 for the user to breathe.

[0022] As the filter element 508 gradually becomes clogged due to the accumulation of contaminants, the resistance to airflow through it increases, leading to a rise in the pressure difference between the filter chamber and the central area of ​​the housing 501. When the pressure difference reaches a preset threshold, the rotating mechanism 506 is automatically activated by the pressure difference, causing the annular baffle 503 to rotate around its axis by a certain angle. This disconnects the inlet 504 from the current filter chamber and connects it to the next unused filter chamber, automatically switching to a new filter element 508 for continued operation. This process is repeated until all filter elements 508 are used up, enabling multiple filter elements 508 to work independently and switch automatically and seamlessly, significantly extending the continuous protection time of the respirator.

[0023] Example 2: The solution in Example 1 will be further described below with reference to its specific working method. See the description below for details: In this embodiment, the rotating mechanism 506 includes a sleeve 5061, a first slip ring 5062, a slide rod 5063, a slide plate 5064, a return spring 5065, a second slip ring 5066, a connecting rod 5067, a corrugated guide groove 5068, and a guide block 5069. The sleeve 5061 is coaxially fixed to the inner side of the cover plate 502, and one end of the sleeve 5061 passes through the cover plate 502 and communicates with the outside. The first slip ring 5062 is fixedly installed inside the sleeve 5061 at the end away from the cover plate 502; The slide rod 5063 is coaxially slidably inserted inside the sleeve 5061. One end of the slide rod 5063 near the cover plate 502 extends out of the sleeve 5061 and is fixedly connected to the slide plate 5064. The slide plate 5064 slides and seals with the end face of the sleeve 5061. The return spring 5065 is sleeved on the outside of the slide rod 5063, and the two ends of the return spring 5065 abut against the slide plate 5064 and the first slip ring 5062 respectively. The second slip ring 5066 is coaxially disposed on the side of the first slip ring 5062, and the second slip ring 5066 is fixedly connected to the inner wall of the annular baffle 503 through the connecting rod 5067. The inner wall of the second slip ring 5066 is provided with a corrugated guide groove 5068 extending in the circumferential direction, and the outer wall of the slide rod 5063 is fixed with a guide block 5069 that slides in cooperation with the corrugated guide groove 5068.

[0024] During normal operation, the spring force of the return spring 5065 pushes the slide plate 5064 outward, so that the slide plate 5064 fits against the outer end face of the sleeve 5061. At this time, the slide rod 5063 is in the extended state, the guide block 5069 is located at the crest of the corrugated guide groove 5068, the annular baffle 503 remains stationary, and the through port 504 is stably connected to the current filter chamber.

[0025] When the filter element 508 becomes clogged, causing an increase in negative pressure in the central area of ​​the housing 501, the pressure difference between the external atmospheric pressure and the internal negative pressure of the housing 501 acts on the sliding plate 5064, overcoming the elastic force of the return spring 5065 and pushing the sliding plate 5064 inward. This, in turn, causes the sliding rod 5063 to slide axially inward along the sleeve 5061. As the sliding rod 5063 slides, the guide block 5069 on its outer wall slides along the corrugated guide groove 5068 on the inner wall of the second slip ring 5066. Since the corrugated guide groove 5068 is a circumferentially inclined structure, the axial movement of the guide block 5069 is converted into the circumferential rotational movement of the second slip ring 5066. The second slip ring 5066 drives the annular baffle 503 to rotate synchronously through the connecting rod 5067, causing the inlet 504 to switch to the next filter chamber.

[0026] After the switching is completed, the new filter element 508 is turned on, the negative pressure in the central area of ​​the housing 501 returns to the normal level, the reset spring 5065 pushes the slide plate 5064 and the slide rod 5063 to reset outward, the guide block 5069 slides along the corrugated guide groove 5068 to the next crest position, and the annular baffle 503 locks again, completing one automatic switching cycle.

[0027] In this embodiment, a limiting disc 50610 is fixedly sleeved on the outer side of the end of the sleeve 5061 away from the cover plate 502. The limiting disc 50610 is located between the first slip ring 5062 and the annular baffle 503, and the outer wall of the limiting disc 50610 slides against the inner wall of the annular baffle 503. Multiple first air holes 50611 are evenly provided on the limiting plate 50610 to connect the filter chamber with the central area of ​​the housing 501.

[0028] The limiting plate 50610 provides radial support and positioning for the annular baffle 503, preventing radial displacement during rotation and ensuring the alignment accuracy between the inlet 504 and the filter chamber. On the other hand, the first air hole 50611 on the limiting plate 50610 serves as an airflow passage, allowing air entering the inner side of the annular baffle 503 through the inlet 504 to flow smoothly to the central area of ​​the housing 501 and be drawn in by the fan 301.

[0029] In this embodiment, the sealing mechanism 509 includes a fixing block 5091, a support rod 5092, a sleeve 5093, a compression spring 5094, and a second air hole 5095; The fixing block 5091 is correspondingly disposed on the inner side of the mounting port 507, and the fixing block 5091 is fixedly connected to the inner wall of the housing 501 through the support rod 5092; The sleeve 5093 is slidably embedded inside the mounting port 507. The outer end of the sleeve 5093 can abut against the connector of the filter element 508, and the inner end of the sleeve 5093 abuts against one end of the compression spring 5094. The other end of the compression spring 5094 abuts against the fixed block 5091; The sleeve 5093 has a second air hole 5095 evenly opened along the circumference of the side wall.

[0030] When the installation port 507 is not fitted with a filter element 508, the elastic force of the compression spring 5094 pushes the sleeve 5093 to slide outward along the installation port 507 until the outer end of the sleeve 5093 is flush with the outer end face of the installation port 507. At this time, the second vent 5095 on the side wall of the sleeve 5093 is completely located inside the installation port 507 and is blocked by the radial inner wall of the installation port 507, realizing the automatic sealing of the empty installation port 507 and preventing external polluted air from entering the filter chamber through the interface where the filter element 508 is not installed.

[0031] When filter element 508 needs to be installed, screw or snap the connector of filter element 508 into the installation port 507. The end face of the connector of filter element 508 pushes the sleeve 5093 inward to slide, compressing the compression spring 5094. When filter element 508 is installed in place, the second vent 5095 on the side wall of sleeve 5093 fully enters the filter chamber, allowing the interior of filter element 508 to communicate with the filter chamber through the second vent 5095, and the air passage is automatically opened. After removing filter element 508, the compression spring 5094 automatically pushes sleeve 5093 back to its original position, resealing the installation port 507. No additional sealing parts are required, enabling flexible assembly of filter element 508.

[0032] In this embodiment, the annular baffle 503 has only one opening 504 to ensure that only one filter chamber is connected to the central area of ​​the housing 501 at any time. The remaining filter chambers are sealed and isolated by the annular baffle 503, so that the filter elements 508 can be used independently one by one. There are 3 sets of partitions 505, which form 3 independent filter chambers and can install 3 filter elements 508, thus extending the continuous protection time of the respirator.

[0033] In this embodiment, the filter element 508 and the mounting port 507 are connected by a threaded connection or a snap-fit ​​connection to achieve detachable installation. The threaded connection or snap-fit ​​connection makes the installation and removal of the filter element 508 simple and quick. Users can flexibly choose to install 1-3 filter elements 508 according to the actual working time requirements.

[0034] In this embodiment, a sealing gasket is provided at the outer end of the sleeve 5093, and the sealing gasket fits against the inner wall of the mounting port 507. The sealing gasket at the outer end of the sleeve 5093 can fill the gap between the sleeve 5093 and the inner wall of the mounting port 507, improve the sealing performance of the unused interface, and prevent leakage under high negative pressure conditions.

[0035] In this embodiment, a guide ring is fixed inside the housing 501 at the end away from the cover plate 502. The outer wall of the guide ring fits against the inner side of the annular baffle 503. The guide ring and the limiting disk 50610 together form a double-end support structure for the annular baffle 503, which further improves the rotational stability and coaxiality of the annular baffle 503, prevents the annular baffle 503 from tilting or jamming during long-term use, and ensures the reliability of the automatic switching action.

[0036] In this embodiment, the first slip ring 5062 is located at the axial centerline inside the sleeve 5061, and reinforcing rods are uniformly provided between the outer side of the first slip ring 5062 and the inner wall of the sleeve 5061. The reinforcing rods can enhance the structural strength of the first slip ring 5062, prevent the first slip ring 5062 from deforming or loosening during frequent switching, and extend the service life of the rotating mechanism 506.

[0037] In this embodiment, there are 3 sets of filter elements 508, and each filter element 508 corresponds to 3 independent filter chambers. The filter elements 508 are located on both sides and below the waist. The air guide pipe 2 is located at the top of the air supply box 3 to avoid interference between the filter elements 508 and the air guide pipe 2.

[0038] The solutions in Embodiment 1 and Embodiment 2 will be further described below with reference to their specific working methods. Preparation phase: Based on the degree of pollution in the working environment and the expected duration, install the corresponding number of filter elements 508 at the corresponding installation port 507 as needed. During installation, the filter element 508 connector pushes the sleeve 5093 inward, and the second air hole 5095 enters the filter chamber, opening the air passage; the interface without filter element 508 installed is automatically sealed by the sealing mechanism 509.

[0039] Normal operating phase: When the fan 301 is started, outside air enters the corresponding filter chamber after being filtered through the first filter element 508, and then enters the central area of ​​the housing 501 through the inlet 504 and the first air hole 50611. After being pressurized by the fan 301, it is sent into the face mask 1. At this time, the return spring 5065 pushes the slide plate 5064 to the extended position, and the annular baffle 503 is locked.

[0040] Automatic switching phase: When the first filter element 508 becomes clogged, the negative pressure at the center of the housing 501 increases. The pressure difference pushes the sliding plate 5064 inward, causing the sliding rod 5063 and guide block 5069 to move axially. The guide block 5069 slides along the corrugated guide groove 5068, driving the second slip ring 5066 and the annular baffle 503 to rotate 120°, switching the port 504 to the second filter chamber, and the second filter element 508 begins to work. Subsequently, the reset spring 5065 pushes the sliding rod 5063 to reset, and the annular baffle 503 locks again.

[0041] Repeated switching phase: When the second filter element 508 becomes clogged, the above switching process is repeated, and the third filter element 508 is automatically activated.

[0042] Replacement phase: After all 508 filter elements have been used, the user should evacuate to a safe area, remove and replace the expired 508 filter element individually, and then put it back into use.

[0043] The above description is merely a further embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope disclosed in the present invention, based on the technical solution and concept of the present invention, shall fall within the scope of protection of the present invention.

Claims

1. A self-filtering forced-air respirator, comprising a mask (1), an air duct (2), an air supply box (3), a waist belt (4), and a filter assembly (5), wherein a fan (301) is provided inside the air supply box (3), and the mask (1) is connected to the air outlet of the air supply box (3) through the air duct (2), characterized in that: The filter assembly (5) includes a housing (501), a cover plate (502), an annular baffle (503), a partition plate (505), a rotating mechanism (506), a mounting port (507), a filter element (508), and a sealing mechanism (509) corresponding to the mounting port (507). The housing (501) has an open end, and the cover plate (502) is sealed and fixed to the open end; The annular baffle (503) is coaxially rotatably installed inside the housing (501), and the partition (505) is evenly distributed circumferentially between the inner wall of the housing (501) and the outer wall of the annular baffle (503), dividing the space between the housing (501) and the annular baffle (503) into multiple independent filter chambers; An opening (504) is provided on the annular baffle (503). When the annular baffle (503) rotates, the opening (504) can sequentially connect with different filter chambers. The air inlet of the fan (301) is connected to the central area of ​​the casing (501); The rotating mechanism (506) is located inside the housing (501) and is used to drive the annular baffle (503) to rotate when the filter element (508) corresponding to the currently open filter chamber is blocked, causing the air pressure to rise. This allows the port (504) to switch to the next unused filter chamber, thus enabling the filter element (508) to be automatically switched one by one for use. The mounting port (507) is circumferentially opened on the side wall of the housing (501) and is connected to multiple filter chambers one by one. A filter element (508) can be detachably installed at each mounting port (507). A sealing mechanism (509) is provided at each mounting port (507) to automatically seal the mounting port (507) when no filter element (508) is installed in the mounting port (507).

2. The self-filtering forced-air respirator according to claim 1, characterized in that: The rotating mechanism (506) includes a sleeve (5061), a first slip ring (5062), a slide rod (5063), a slide plate (5064), a return spring (5065), a second slip ring (5066), a connecting rod (5067), a corrugated guide groove (5068), and a guide block (5069). The sleeve (5061) is coaxially fixed to the inner side of the cover plate (502), and one end of the sleeve (5061) passes through the cover plate (502) and communicates with the outside. The first slip ring (5062) is fixedly installed inside the sleeve (5061) at one end away from the cover plate (502); The slide rod (5063) is coaxially slidably inserted inside the sleeve (5061). One end of the slide rod (5063) near the cover plate (502) extends out of the sleeve (5061) and is fixedly connected to the slide plate (5064). The slide plate (5064) and the end face of the sleeve (5061) slide and seal in a sealing fit. The return spring (5065) is sleeved on the outside of the slide rod (5063), and the two ends of the return spring (5065) abut against the slide plate (5064) and the first slip ring (5062) respectively; The second slip ring (5066) is coaxially disposed on the side of the first slip ring (5062), and the second slip ring (5066) is fixedly connected to the inner wall of the annular baffle (503) through the connecting rod (5067); The inner wall of the second slip ring (5066) is provided with a corrugated guide groove (5068) extending in the circumferential direction, and the outer wall of the slide rod (5063) is fixed with a guide block (5069) that slides in cooperation with the corrugated guide groove (5068).

3. A self-filtering forced-air respirator according to claim 2, characterized in that: A limiting disc (50610) is fixedly fitted on the outer side of the end of the sleeve (5061) away from the cover plate (502). The limiting disc (50610) is located between the first slip ring (5062) and the annular baffle (503), and the outer wall of the limiting disc (50610) slides against the inner wall of the annular baffle (503). Multiple first air holes (50611) are evenly provided on the limiting plate (50610) to connect the filter chamber with the central area of ​​the housing (501).

4. A self-filtering forced-air respirator according to claim 1, characterized in that: The sealing mechanism (509) includes a fixing block (5091), a support rod (5092), a sleeve (5093), a compression spring (5094), and a second vent (5095); The fixing block (5091) is located on the inner side of the mounting port (507), and the fixing block (5091) is fixedly connected to the inner wall of the housing (501) through the support rod (5092); The sleeve (5093) is slidably embedded in the mounting port (507). The outer end of the sleeve (5093) can abut against the connector of the filter element (508), and the inner end of the sleeve (5093) abuts against one end of the compression spring (5094). The other end of the compression spring (5094) abuts against the fixed block (5091); The sleeve (5093) has a second air hole (5095) evenly opened along the circumference of the side wall.

5. A self-filtering forced-air respirator according to claim 1, characterized in that: The annular baffle (503) has only one opening (504), and the number of partitions (505) is 3 sets, which correspond to form 3 independent filter chambers.

6. A self-filtering forced-air respirator according to claim 1, characterized in that: The filter element (508) and the mounting port (507) are connected by a threaded connection or a snap-fit ​​connection to achieve detachable installation.

7. A self-filtering forced-air respirator according to claim 4, characterized in that: The outer end of the sleeve (5093) is provided with a sealing gasket, and the sealing gasket fits against the inner wall of the mounting port (507).

8. A self-filtering forced-air respirator according to claim 1, characterized in that: A guide ring is fixed inside the housing (501) at one end away from the cover plate (502), and the outer wall of the guide ring is in contact with the inner side of the annular baffle (503).

9. A self-filtering forced-air respirator according to claim 2, characterized in that: The first slip ring (5062) is located at the axial centerline inside the sleeve (5061), and reinforcing rods are uniformly provided between the outer side of the first slip ring (5062) and the inner wall of the sleeve (5061).

10. A self-filtering forced-air respirator according to claim 1, characterized in that: There are 3 sets of filter elements (508), and each filter element (508) corresponds to 3 independent filter chambers.

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