Air purification air supply welding protection helmet structure

Abstract

The utility model belongs to the technical field of protective helmets, and particularly relates to an air purification air supply welding protective helmet structure which comprises a helmet body, a welding mask and a protective mask, and the welding mask is rotatably connected to the front side of the helmet body and used for protecting the face, the eyes, the mouth and the nose; the air duct is arranged in the helmet body and provided with an air outlet and an air inlet, and the air outlet is located in the bottom side of the front end of the helmet body so that airflow can be sent to the face; the air purification and supply device is connected with the air inlet and used for inputting purified air into the air duct. Due to the fact that the air outlet of the air channel extends to the bottom side of the front end of the helmet body, purified air blown out of the air outlet can be directly blown to the face, the mouth and the nose of the human body, and the comfort degree of workers is high. And the air purifying and supplying device and the battery are arranged on the back side of the helmet main body, so that an external power supply and an air purifying pipeline are not needed, the helmet is very convenient to wear, and the action space of a worker is not limited.

Description

Technical Field

[0001] The utility model belongs to the technical field of protective helmets, and particularly relates to a structure of an air purification and air supply welding protective helmet. Background Art

[0002] Welding protective helmets are applied in the field of electric welding machines and are used to reasonably protect workers from harm to their heads, faces and eyes. A welding helmet generally includes a peeping main body and a welding protective mask. During welding, the welding protective mask needs to be lowered to cover the human face, so as to protect the human face and eyes.

[0003] For example, the Chinese patent document with the publication number CN111132573A discloses a welding helmet, which includes a head suspension system and a protective cover. The protective cover has or forms a perspective window. The welding helmet further includes a first neck guard. The protective cover is formed with a lower end, and the first neck guard is removably attached to the lower end of the protective cover. It can be used together with the neck guard in the forced air mode, and the neck guard completely covers the front part of the wearer's neck. And it can be used in the non-air mode, in which air is allowed to reach the wearer's mouth and / or nose through the gap or space between the wearer's chin and chest via a different neck guard. The welding helmet has an inlet for connecting the welding helmet to an air supply via a hose (not shown). Such an air supply can be carried out, for example, by a powered air purification unit (known in the field of electric air purification respirators (PAPR)). Therefore, the wearer of the welding helmet can be supplied with forced fresh air between the protective cover and the wearer's head (and face).

[0004] It can be seen that in the technical solution of the welding helmet disclosed in the above patent document, the externally purified air is input into the helmet to provide purified air inside the helmet, and the purified air can be breathed by the human body. However, the technical solution disclosed in this patent document is that after the air enters the helmet, the wearer of the welding helmet can be supplied with forced fresh air between the protective cover and the wearer's head (and face). Since the head and face of the worker will sweat and other problems after wearing the helmet, there will be a smell of sweat in the air inside the helmet, which will cause discomfort to the human body. In addition, there is generally flowing sweat on the face and forehead of the human body. Therefore, the worker often needs to take off the helmet to breathe, etc., which causes inconvenience to the worker. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a structure of an air purification and air supply welding protective helmet, so as to solve the problems of discomfort and inconvenience caused to workers when wearing existing welding helmets.

[0006] To achieve the above object, an air purification and air supply welding protection helmet structure provided by an embodiment of the present utility model is used for electric welding protection, and includes a helmet main body and a welding mask. The welding mask is rotatably connected to the front side of the helmet main body for protecting the face, eyes, mouth and nose. It further includes an air duct and an air purification and air supply device. The air duct is arranged inside the helmet main body. The air duct has an air outlet and an air inlet. The air outlet is located at the bottom side of the front end of the helmet main body, so that air flow can blow towards the face. The air purification and air supply device is connected to the air inlet for inputting purified air into the air duct.

[0007] Further, an installation cavity is arranged on the back side of the helmet main body, and the air purification and air supply device is arranged in the installation cavity.

[0008] Further, the air purification and air supply device includes a filter element, a blower and a filter element cover plate. The filter element is arranged in the installation cavity. The filter element cover plate covers the opening of the installation cavity and limits the filter element in the installation cavity. Air holes are arranged on the bottom wall of the installation cavity. The blower is connected to the bottom wall and the blower communicates with the air holes.

[0009] Further, an inner shell is further arranged on the inner side of the helmet main body closer to the installation cavity. The inner shell and the bottom wall of the installation cavity enclose an isolation cavity, and the blower is arranged in the isolation cavity.

[0010] Further, a bottom plate is arranged at the bottom end of the inner shell. The bottom plate seals the bottom of the isolation cavity. A battery compartment extending into the isolation cavity is arranged on the bottom plate, and a battery is arranged in the battery compartment for supplying electric energy to the blower.

[0011] Further, a control circuit is further arranged in the isolation cavity. The control circuit is connected to the battery and the blower, and the operation buttons of the control circuit are arranged on the bottom side of the bottom plate.

[0012] Further, the blower is a centrifugal blower and is arranged on the outer side wall of the installation cavity. The air suction port of the centrifugal blower is hermetically communicated with the air hole. The air discharge port of the centrifugal blower extends upward in a curved manner. One end of the air duct extends into the isolation cavity, and the air inlet is sleeved on the air discharge port. The inner shell supports one end of the air duct.

[0013] Further, a bracket is arranged at the bottom side of the front end of the helmet main body. The bracket is provided with a flat hole, and a convex ring extends upward from the edge of the flat hole. The air outlet is sleeved on the convex ring, so that the bracket supports the air outlet end of the air duct.

[0014] Further, the air duct gradually becomes wider from the air inlet to the air outlet direction, so that a silent cavity is formed in the air duct.

[0015] Further, a limit switch is also provided inside the helmet body. One end of the limit switch passes through the bottom wall and extends into the installation cavity to limit the filter element, so that a cavity is formed between the filter element and the bottom wall.

[0016] Further, the air purification and air supply welding protection helmet structure further includes a protection face shield, which is rotatably connected to the front side of the helmet body and located inside the welding face shield; a transparent optical lens is provided on the protection face shield.

[0017] Further, connecting shafts are provided on both sides of the helmet body, and a plurality of first card slots are provided along the connecting shafts. Two first connecting parts extend from the protection face shield, and the first connecting parts are rotatably sleeved on the connecting shafts; first card teeth are provided on the inner sides of the first connecting parts, and the first card teeth are limited in the first card slots; a plurality of second card slots are provided on the outer sides of the first connecting parts. Two second connecting parts extend from the welding face shield. The second connecting parts are connected to the corresponding connecting shafts and the second connecting parts are located outside the first connecting parts; second card teeth are provided on the inner sides of the second connecting parts, and the second card teeth are connected to the second card slots in a limiting manner.

[0018] Further, a sealing cover is further provided on the side of the welding face shield closer to the face. An accommodating cavity is formed between the sealing cover and the inner side of the welding face shield. An avoidance opening is provided on one side of the sealing cover, and the edge of the avoidance opening is used to fit with the lower jaw and the side face.

[0019] At least the following technical effects are achieved by one or more of the above technical solutions in the air purification and air supply welding protection helmet structure provided by the embodiments of the present invention:

[0020] 1. An air duct is provided inside the helmet body, and the air inlet of the air duct is connected to the air purification and air supply device. Therefore, the air purification and air supply device can convey the filtered and purified air into the air duct. Since the air outlet of the air duct extends to the front bottom side of the helmet body, the purified air blown out from the air outlet can directly blow towards the face of the human body; therefore, the human body can breathe the purified air by itself, avoiding the purified air being mixed with the smell of sweat. And since the air directly blows towards the face of the person, it can dissipate heat and cool down the face of the human body and remove sweat; it can avoid the problem that the sweat flowing on the face and eyes causes discomfort to the human body.

[0021] 2. The air purification and air supply device and the battery are arranged on the back side of the helmet body. Therefore, there is no need to connect an external power supply and a pipeline for purifying air, and the wearing is very convenient without restricting the movement space of the staff. And the welding face shield and the air purification and air supply device are arranged on the front and back sides of the head body, and can also play a role of mutual counterweight, avoiding the problem that the front side is too heavy and causes unbalanced wearing and increased discomfort of the human body. Description of the Drawings

[0022] To more clearly illustrate the technical solutions in the embodiments of the present utility model, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0023] Figure 1 It is a structural diagram of the air purification and air supply welding protection helmet structure provided by the embodiment of the present utility model.

[0024] Figure 2 It is an internal structural diagram of the air purification and air supply welding protection helmet structure provided by the embodiment of the present utility model.

[0025] Figure 3 It is a cross-sectional view of the air purification and air supply welding protection helmet structure provided by the embodiment of the present utility model.

[0026] Figure 4 It is an exploded view of the air purification and air supply welding protection helmet structure provided by the embodiment of the present utility model.

[0027] Figure 5 It is a schematic diagram of the welding mask of the air purification and air supply welding protection helmet structure provided by the embodiment of the present utility model being opened.

[0028] Figure 6 It is a structural diagram of the protective mask of the air purification and air supply welding protection helmet structure provided by the embodiment of the present utility model.

[0029] Figure 7 It is a structural diagram of the welding mask of the air purification and air supply welding protection helmet structure provided by the embodiment of the present utility model.

[0030] Figure 8 It is a structural diagram of the air purification and air supply welding protection helmet provided by the embodiment of the present utility model with a sealing cover.

[0031] Figure 9 It is a cross-sectional view of the air purification and air supply welding protection helmet provided by the embodiment of the present utility model with a sealing cover. Detailed implementation manners

[0032] The following will describe in detail the embodiments of the present utility model. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below by referring to the drawings are exemplary and are intended to explain the embodiments of the present utility model, and should not be construed as a limitation of the present utility model.

[0033] In the description of the embodiments of the present utility model, it should be understood that the orientation or positional relationships indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation on the present utility model.

[0034] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present utility model, "a plurality of" means two or more, unless otherwise specifically defined.

[0035] In the embodiments of the present utility model, unless otherwise clearly specified and limited, the terms "mounted", "connected", "connected to", "fixed", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.

[0036] In an embodiment of the air purification and air supply welding protection helmet structure of the present utility model, please refer to Figures 1 to 4; The air purification and air supply welding protection helmet structure of this embodiment is used for welding protection and plays a protective role for the head, face and eyes of the staff. Specifically, it includes a helmet main body 100, a welding mask 200, an air duct 400 and an air purification and air supply device 300. Among them, the welding mask 200 is rotatably connected to the front side of the helmet main body 100, and the welding mask 200 plays a protective role for the face and eyes of the human body. The air duct 400 is arranged inside the helmet main body 100. The air duct 400 has an air outlet 401 and an air inlet 402. The air outlet 401 extends to the front bottom side of the helmet main body 100, so that the air flow blown out from the air outlet 401 can directly blow towards the face of the human body. The air purification and air supply device 300 is connected to the air inlet 402 and is used to input purified air into the air duct 400. Specifically, in this embodiment, because the air duct 400 is arranged inside the helmet main body 100 and the air inlet 402 of the air duct 400 is connected to the air purification and air supply device 300, the air purification and air supply device 300 can transport filtered and purified air into the air duct 400. Since the air outlet of the air duct 400 extends to the front bottom side of the helmet main body 100, the purified air blown out from the air outlet 401 can directly blow towards the face of the human body; therefore, the human body can breathe the purified air by itself, avoiding the purified air being mixed with the smell of sweat. And the air directly blows towards the face of the person, which can dissipate heat and cool down the face of the human body and remove sweat; avoiding the problem that the sweat flowing on the face and eyes causes discomfort to the human body.

[0037] Furthermore, in order to further protect the staff, a sealing cover 900 is further provided on the side of the welding mask 200 closer to the face. Specifically, please refer to Figure 8 and Figure 9 , a receiving cavity 901 is formed between the sealing cover 900 and the inner side of the welding mask 200. An avoidance opening 902 is provided on one side of the sealing cover 900, and the edge of the avoidance opening 902 is used to fit with the lower jaw and the side face of the human body. Specifically, when the staff wears it, the helmet main body 100 can be worn on the head of the human body. When the welding mask 200 is turned down to cover the face, the face of the staff enters the receiving cavity 901 through the avoidance opening 902, and the edge of the avoidance opening 902 fits with the lower jaw and the side face, so that the face is protected in the receiving cavity 901, avoiding the entry of external dust and the like. Further, an installation groove is provided on the side of the welding mask 200, and the edge of the sealing cover 900 is snapped into the installation groove, so that the sealing cover 900 and the welding mask 200 are combined into one body.

[0038] Further, refer to Figure 1 and Figure 4, an installation cavity 101 is provided on the dorsal side of the helmet main body 100, and the air purification and air supply device 300 is arranged in the installation cavity 101. In this embodiment, the air purification and air supply device 300 is arranged in the installation cavity 101 of the helmet main body 100, which is convenient to wear and makes the movement freer. In addition, the air purification and air supply device 300 and the welding mask 200 are counterweighted with each other, so that the front and rear forces are balanced, avoiding the problem of unbalanced wearing caused by too heavy front side and increasing the discomfort of the human body. Further, a battery 500 is also arranged in the helmet main body 100, and the battery 500 directly provides electric energy for the air purification and air supply device 300, so there is no need for an external power supply.

[0039] Further, referring to Figure 1 of Figure 4 , the air purification and air supply device 300 includes a filter element 310, a blower 320 and a filter element cover plate 330. The filter element 310 is arranged in the installation cavity 101, the filter element cover plate 330 covers the opening of the installation cavity 101, and limits the filter element 310 in the installation cavity 101; a plurality of air grooves are provided on the filter element cover plate 330. An air hole 103 is provided on the bottom wall 102 of the installation cavity 101, and the blower 320 is connected to the bottom wall 102 and the blower 320 communicates with the air hole 103. In this embodiment, the blower 320 forms a suction force, so that the air enters the air duct 400 after being filtered by the filter element 310, and the air entering the helmet main body 100 is purified.

[0040] Further, please refer to Figure 2 of Figure 3 , an inner shell 600 is further provided on the inner side of the helmet main body 100 closer to the installation cavity body 101. The inner shell 600 and the bottom wall 102 of the installation cavity 101 enclose an isolation cavity 104, and the blower 320 is arranged in the isolation cavity 104. In this embodiment, the blower 320 is arranged in the isolation cavity 104 spaced from the installation cavity 101. Therefore, when replacing the filter element 330, the structure of the blower 320 will not be affected. In addition, the blower 320 is arranged in the isolation cavity 104, which is more convenient for connecting the air duct 400 and the blower 320.

[0041] Further, please refer to Figures 2 to 4 , a bottom plate 601 is provided at the bottom end of the inner shell 600, and the bottom plate 601 seals the bottom of the isolation cavity 104. The bottom plate 601 is provided with a battery compartment 602 extending into the isolation cavity 104, and the battery compartment 602 is used for installing the battery 500. Therefore, the overall structure is more compact, saving space, and it is also convenient for replacing the battery 500.

[0042] Further, referring to Figure 4 , a control circuit 700 is also arranged in the isolation cavity 104. The control circuit 700 is connected to the battery 500 and the blower 320, and the control button 701 of the control circuit 700 is arranged on the bottom side of the bottom plate 601.

[0043] Furthermore, referring to Figure 3 and Figure 4 , the blower 320 is a centrifugal blower and is provided on the outer side wall of the installation cavity 101. The air inlet of the centrifugal blower is in sealed communication with the air hole 103. The air outlet 321 of the centrifugal blower extends upward in a curved manner. One end of the air duct 400 extends into the isolation cavity, and the air inlet 402 is sleeved on the air outlet 321 of the blower 320; and the inner shell 600 supports the air inlet end of the air duct 400. In this embodiment, the air outlet 321 of the blower 320 extends in a curved manner, so it is convenient to connect the air duct 400 to the blower 320. And the blower 320 adopts a centrifugal blower, which can better transport the purified air into the air duct 400.

[0044] Furthermore, please refer to Figure 2 and Figure 4 , a bracket 110 is provided on the bottom side of the front end of the helmet body 100. The bracket 110 is provided with a flat hole 111. A convex ring 112 extends upward from the edge of the flat hole 111. The air outlet 401 is sleeved on the convex ring 112, so that the bracket 110 supports the air outlet end of the air duct 400. Therefore, the air duct 400 can be supported by the inner shell 600 and the bracket 110 and fixed inside the helmet body 100.

[0045] Furthermore, referring to Figure 2 , the air duct 400 gradually widens from the air inlet 402 to the air outlet 401, so as to form a silent cavity in the air duct 400. In this embodiment, the cross-sectional width of the air duct 400 gradually widens, so that the air flow can be made more smooth, and the pressure between the air flow and the inner wall of the air duct 400 can be reduced to conduct air friction, thereby reducing noise.

[0046] Furthermore, referring to Figure 1 , a limit switch 120 is further provided inside the helmet body 100. The main body part of the limit switch 120 is arranged in the isolation cavity 104 and is connected to the control circuit 700. The other end of the limit switch 120 passes through the bottom wall 102 and extends into the installation cavity 101 to limit the filter element 310, so that a cavity 311 is formed between the filter element 310 and the bottom wall. Therefore, local filtration of the filter element 310 will not occur, but the filtration of the filter element 310 can be fully utilized to filter the air. In addition, by limiting the filter element 310 with the limit switch 120, when the filter element 310 does not touch the limit switch 120, the blower 320 cannot be started, avoiding the problem that the filter element 310 is not assembled to the sealed position, resulting in a gap with the inner side wall of the installation cavity 101 and unable to filter the air completely.

[0047] Furthermore, referring to Figures 5 to 7, the air purification and air supply welding protection helmet structure further includes a protection mask 800, which is rotatably connected to the front side of the helmet body 100 and is located inside the welding mask 200. A transparent optical lens 801 is provided on the protection mask 800. In the protection helmet of this embodiment, it can also be applied to work such as grinding, polishing, and cutting to protect the staff. Specifically, when using the protection mask 800, the welding mask 200 can be turned up, and the protection mask 800 protects the human face, and the transparent optical lens 801 on the protection mask 800 does not affect the vision of the staff.

[0048] Further, please refer to Figures 5 to 7 , connecting shafts 130 are provided on both sides of the helmet body 100, and a plurality of first card slots 105 are provided along the connecting shafts 130. The protection mask 800 extends two first connecting parts 802, and the first connecting parts 802 are rotatably sleeved on the connecting shafts 130. A first card tooth 803 is provided on the inner side of the first connecting part 802, and the first card tooth 803 is limited in the first card slot 105. When the protection mask 800 is turned up, it has multiple opening angles. A plurality of second card slots 804 are provided on the outer side of the first connecting part 802. The welding mask 200 extends two second connecting parts 201, and the second connecting parts 201 are connected to the corresponding connecting shafts 130 and the second connecting parts 201 are located outside the first connecting parts 802; a second card tooth 202 is provided on the inner side of the second connecting part 201, and the second card tooth 202 is limitedly connected to the second card slot 804. The welding mask 800 has multiple opening angles and can be turned up and opened independently of the protection mask 800.

[0049] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An air purification and air supply welding protective helmet structure, used for electric welding protection, comprising a helmet body and a welding mask, wherein the welding mask can be rotatably connected to the front side of the helmet body to protect the face and eyes; characterized in that: It also includes an air duct and an air purification and air supply device. The air duct is arranged in the helmet body. The air duct has an air outlet and an air inlet. The air outlet is located at the bottom side of the front end of the helmet body so that the air flow can blow to the face and mouth and nose; the air purification and air supply device is connected to the air inlet and is used to input purified air into the air duct.

2. The air purification and air supply welding protective helmet structure according to claim 1 is characterized in that: A mounting cavity is provided on the back side of the helmet body, and the air purification and air supply device is arranged in the mounting cavity.

3. The air purification and air supply welding protective helmet structure according to claim 2 is characterized in that: The air purification and air supply device includes a filter element, a blower and a filter element cover; the filter element is arranged in the installation cavity, the filter element cover covers the mouth of the installation cavity and limits the filter element in the installation cavity; the bottom wall of the installation cavity is provided with an air hole, the blower is connected to the bottom wall, and the blower is connected to the air hole.

4. The air purification and air supply welding protective helmet structure according to claim 3 is characterized in that: An inner side of the helmet body closer to the installation cavity is also provided with an inner shell, and the inner shell and the bottom wall of the installation cavity form an isolation cavity, and the blower is arranged in the isolation cavity.

5. The air purification and air supply welding protective helmet structure according to claim 4 is characterized in that: A bottom plate is provided at the bottom end of the inner shell, and the bottom plate seals the bottom of the isolation cavity; the bottom plate is provided with a battery compartment extending into the isolation cavity, and a battery is provided in the battery compartment for providing electrical energy to the blower.

6. The air purification and air supply welding protective helmet structure according to claim 5 is characterized in that: A control circuit is also provided in the isolation cavity, the control circuit is connected to the battery and the blower, and the control button of the control circuit is provided on the bottom side of the bottom plate.

7. The air purification and air supply welding protective helmet structure according to any one of claims 4 to 6, characterized in that: The blower is a centrifugal fan and is arranged on the outer wall of the installation cavity. The air inlet of the centrifugal fan is sealed and connected with the air hole. The air outlet of the centrifugal fan extends upward in a curved manner. One end of the air duct extends into the isolation cavity. The air inlet is sleeved on the air outlet. The inner shell supports one end of the air duct.

8. The air purification and air supply welding protective helmet structure according to claim 7 is characterized in that: A bracket is provided at the bottom side of the front end of the helmet body, and the bracket is provided with a flat hole. A convex ring extends upward from the edge of the flat hole, and the air outlet is sleeved on the convex ring, so that the bracket supports the air outlet end of the air duct.

9. The air purification and air supply welding protective helmet structure according to any one of claims 1 to 6, characterized in that: The air duct gradually widens from the air inlet to the air outlet, so that a silent cavity is formed in the air duct.

10. The air purification and air supply welding protective helmet structure according to any one of claims 3 to 6, characterized in that: A limit switch is also provided on the inner side of the helmet body, one end of which passes through the bottom wall and extends into the installation cavity, and is used to limit the filter element so that the filter element and the bottom wall form a cavity.

11. The air purification and air supply welding protective helmet structure according to claim 1 is characterized in that: It also includes a protective mask which is rotatably connected to the front side of the helmet body and is located on the inner side of the welding mask; the protective mask is provided with a transparent optical lens.

12. The air purification and air supply welding protective helmet structure according to claim 11, characterized in that: A connecting shaft is provided on both sides of the helmet body, and a plurality of first slots are provided along the connecting shaft. The protective mask is extended with two first connecting parts, and the first connecting part is rotatably sleeved on the connecting shaft; a first clamping tooth is provided on the inner side of the first connecting part, and the first clamping tooth is limited in the first clamping groove; a plurality of second clamping grooves are provided on the outer side of the first connecting part, and two second connecting parts are extended from the welding mask, and the second connecting part is connected to the corresponding connecting shaft, and the second connecting part is located on the outer side of the first connecting part; a second clamping tooth is provided on the inner side of the second connecting part, and the second clamping tooth is limitedly connected with the second clamping groove.

13. The air purification and air supply welding protective helmet structure according to any one of claims 1 to 5, 11 and 12, characterized in that: A sealing cover is also provided on the side of the welding mask closer to the face, and the sealing cover and the inner side of the welding mask form a containing cavity. An air avoidance opening is provided on one side of the sealing cover, and the edge of the air avoidance opening is used to fit the lower jaw and the side face.

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