Patent Publication Number: US-2022219024-A1

Title: Air supply mechanism with lower air duct, headgear and electric protective equipment

Description:
TECHNICAL FIELD 
     The present invention relates to the field of headgear, in particular to an air supply mechanism with lower air duct, a headgear and an electric protective equipment. 
     BACKGROUND 
     In the field of mechanical processing, especially in the field of welding and grinding where a protective headgear is required, electric protective equipment has been paid more and more attention with the increasing awareness of occupational health and personal protection. This is because in a working environment with poor air quality, electric protective equipment can filter out air that is hazardous to human health and thus reduce harm to the human body. 
     In the prior art, direct blowing is often used to send the filtered air into the headgear, so as to provide fresh air for operators. However, the above-mentioned direct blowing method may cause discomfort for long-term use, especially to the eyes, mouth, and nose, causing problems such as dry eyes, dry mouth and dry tongue. 
     The information disclosed in this background section is only intended to deepen the understanding of the overall background of the present invention, and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art known to those skilled in the art. 
     SUMMARY 
     The technical problem to be solved by the present invention is to provide an air supply mechanism with lower air duct, a headgear and an electric protective equipment, so as to improve the comfort of the operator during use. 
     To this end, the present invention adopts technical solutions detailed below. 
     In one aspect, the present invention provides an air supply mechanism with lower air duct comprising: 
     an air inlet mask, the front of the air inlet mask being raised in an arc shape and the back of the air inlet mask being arranged to fit to the human face, the air inlet mask including a first ventilation structure and a second ventilation structure connecting the front and back; 
     an air supply pipe fixed on one side of the air inlet mask and in communication with the first ventilation structure and the second ventilation structure to supply air to the front of the air inlet mask; 
     a filter screen fixedly covering the first ventilation structure to filter the air entering the first ventilation structure from the front of the air inlet mask; 
     wherein when the air inlet mask fits to the human face, the first ventilation structure is arranged at the position of the nose and mouth and the second ventilation structure is arranged under the eyes, the first ventilation structure is provided with a plurality of ventilation holes, and the second ventilation structure is provided with an air inlet duct arranged toward the upper side in the height direction of the air inlet mask, the front side of the air inlet mask is semi-closed or fully closed, and the air blown by the air supply pipe partially or completely passes into the first ventilation structure and the second ventilation structure, and the diameter of the filter holes of the filter screen is not greater than 2 mm. 
     Further, the plurality of ventilation holes is provided with a ventilation pipe, one end of the ventilation pipe is connected to the front of the air inlet mask where the ventilation holes are located, and the other end extends away from the air inlet mask. 
     Further, the diameter of the end of the ventilation pipe away from the air inlet mask is less than the diameter of the end close to the air inlet mask. 
     Further, the first ventilation structure further includes an enclosure arranged perpendicular to the body of the air inlet mask and surrounding the plurality of the ventilation holes to form an air inlet chamber. 
     Further, the height of the enclosure close to the air supply pipe is lower than the height of the enclosure away from the air supply pipe. 
     Further, the enclosure is arranged open at a central position between the upper and lower sides in the height direction of the air inlet mask. 
     Further, the length direction of the air supply pipe is substantially perpendicular to the body of the air inlet mask, the side of the air inlet mask is recessed inward to form a fixing groove, the side wall of the fixing groove is arranged to replica the shape of the side wall where the air supply pipe is fixed. 
     Further, the filter screen may be detachably fixed to the air inlet mask. 
     The filter screen may be fixed in the air inlet mask by fasteners. 
     Alternatively, a snap structure is provided at a central position between two ends of the filter screen in the width direction, the first ventilation structure is provided with a bayonet corresponding to the snap structure, and the snap structure is detachably seated in the bayonet. 
     In another aspect, the present invention provides a headgear comprising: 
     an air supply mechanism with lower air duct described above and a semi-open hood, the semi-open hood including an internal space for at least covering the human face and an observation window at its front end, the air supply mechanism with lower air duct being fixed inside the semi-open hood; 
     wherein the edge of the air inlet mask in the air supply mechanism with lower air duct extends and bends toward the direction of the semi-open hood, so as to form an air inlet chamber between the air inlet mask and the semi-open hood. 
     In yet another aspect, the present invention also provides an electric protective equipment comprising a headgear described above, a filter-type blower, and a connecting hose connected to the filter-type blower at one end and the air supply pipe in the air supply mechanism with lower air duct at the other end. 
     The present invention is advantageous in that through the arrangement of the ventilation holes at the first ventilation structure on the air inlet mask and the filter screen fixed at the first ventilation structure, the wind entering the mouth and nose from the first ventilation structure becomes more soft and delicate after being filtered through the filter screen, improving the comfort of human body when wearing it, and that through the arrangement of the second ventilation structure, the air inlet duct blows from the inside of the air inlet mask to the observation window of the headgear, preventing the window from fogging and improving the reliability of use. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the accompanying drawings to be used in the description of the embodiments or prior art will be briefly described below. It is obvious that the accompanying drawings in the following description are only some of the embodiments recorded in the present invention, and other accompanying drawings can be obtained according to these accompanying drawings without creative work for those of ordinary skill in the art. 
         FIG. 1  is a schematic diagram of the exploded structure of the air supply mechanism with lower air duct according to an embodiment of the present invention; 
         FIG. 2  is a schematic diagram of the air flow direction in the air supply mechanism with lower air duct according to an embodiment of the present invention; 
         FIG. 3  is a front view of the air supply mechanism with lower air duct according to an embodiment of the present invention; 
         FIG. 4  is a cross-sectional view along the line A-A in  FIG. 3  and a schematic diagram of the wearing structure according to an embodiment of the present invention; 
         FIG. 5  is a front view of the filter screen according to an embodiment of the present invention; 
         FIG. 6  is a side view of  FIG. 5  according to an embodiment of the present invention; 
         FIG. 7  is a schematic diagram of the structure of the headgear according to an embodiment of the present invention; and 
         FIG. 8  is a schematic diagram of the connection structure of the electric protection equipment according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The technical solutions in the embodiments of the present invention will be described clearly and completely in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. 
     It should be noted that when an element is referred to as being “fixed to” another element, it can be directly on the another element or an intermediate element may also be present. It should be noted that when an element is referred to as being “connected to” another element, it can be directly on the another element or an intermediate element may also be present. The terms “vertical,” “horizontal,” “left,” “right,” and similar expressions used herein are for illustrative purposes only and do not mean that they are the only mode of implementation. 
     Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art of the present invention. The terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the invention. The term “and/or” as used herein includes any and all combinations of one or more of the related listed items. 
     In one aspect, the present invention provides an air supply mechanism with lower air duct comprising an air inlet mask  10 , an air supply pipe  20  and a filter screen  30 . 
     The front of the air inlet mask  10  is raised in an arc shape and the back of the air inlet mask  10  is arranged to fit to the human face, the air inlet mask  10  includes a first ventilation structure  11  and a second ventilation structure  12  connecting the front and back. It should be noted here that the air inlet mask  10  may be made of plastic or metal and integrally formed by injection molding, and fitting to the human face here means that the mask has a curvature that substantially matches the human face and does not mean that it is exactly the same shape as the human face. 
     The air supply pipe  20  is fixed on one side of the air inlet mask  10  and in communication with the first ventilation structure  11  and the second ventilation structure  12  to supply air to the front of the air inlet mask  10 . As shown in  FIG. 2 , one end of the air supply pipe  20  is fixed to the front end of the air inlet mask  10  to feed the air from the other end to the front end of the air inlet mask  10 , and then pass the air into the first ventilation structure  11  and the second ventilation structure  12 , and then the air blows on the human face. 
     The filter screen  30  fixedly covers the first ventilation structure  11  to filter the air entering the first ventilation structure  11  from the front of the air inlet mask  10 . The arrangement of the filter screen  30  can refine the wind blown from the first ventilation structure  11 , thereby reducing the pressure of the wind on the human face and thus reducing the discomfort of the human face. 
     When the air inlet mask  10  fits to the human face, the first ventilation structure  11  is arranged at the position of the nose and mouth and the second ventilation structure  12  is arranged under the eyes, the first ventilation structure  11  is provided with a plurality of ventilation holes  11   a , and the second ventilation structure  12  is provided with an air inlet duct arranged toward the upper side in the height direction of the air inlet mask  10 , the front side of the air inlet mask  10  is semi-closed or fully closed, and the air blown by the air supply pipe  20  partially or completely passes into the first ventilation structure  11  and the second ventilation structure  12 , and the diameter of the filter holes of the filter screen  30  is not greater than 2 mm. As shown in  FIG. 3 , the air inlet mask  10  in the embodiment of the present invention is substantially dimensioned to cover the part of the face below the eyes. In addition, it should be noted here that the semi-closed or fully closed configuration of the air inlet mask  10  represents two ways in which the air sent from the air supply pipe  20  at the front end of the air inlet mask  10  enters the first ventilation structure  11  and the second ventilation structure  12 . Specifically, according to the semi-closed configuration, the front end of the air inlet mask  10  is open and an air inlet space is formed through cooperation with the headgear. According to the fully closed configuration, a cover is added to the front end of the mask, so that the air sent from the air supply pipe  20  enters the first ventilation structure  11  and the second ventilation structure  12  from the space between the cover and the air inlet mask  10 . By replacing the direct blowing method in the prior art by the present invention which allows the air to enter the air inlet space from the opposite direction and then be filtered, the discomfort caused by the wind pressure of the aerodynamic source directly applied to the face can be reduced. 
     In specific implementation, as shown in  FIGS. 2 and 4 , the air enters from the rear end of the air supply pipe  20  and exits from the front end, and then enters the air inlet mask  10  through the first ventilation structure  11  and the second ventilation structure  12 . The air passing through the first ventilation structure  11  needs to be filtered by the filter screen  30  before contacting with the human mouth and nose area. The second ventilation structure  12  is provided with an air inlet channel  12   a  as shown in  FIG. 4  from the inside of the air inlet mask  10 , the air inlet channel  12   a  blows from the inside to the lens on the observation window, thereby preventing the lens from fogging and affecting the observation. 
     In the above embodiment, with the arrangement of the ventilation holes at the first ventilation structure  11  on the air inlet mask  10  and the filter screen  30  fixed at the first ventilation structure  11 , the wind entering the mouth and nose from the first ventilation structure  11  becomes more soft and delicate after being filtered through the filter screen  30 , improving the comfort of human body when wearing it. In addition, with the arrangement of the second ventilation structure  12 , the air inlet duct blows from the inside of the air inlet mask  10  to the observation window  41  of the headgear (see  FIG. 7 ), preventing the window from fogging and improving the reliability of use. 
     On the basis of the above-mentioned embodiment, in order to make the air blown to the human face more uniform and delicate, the plurality of ventilation holes  11   a  is provided with a ventilation pipe  11   b , one end of the ventilation pipe  11   b  is connected to the front of the air inlet mask  10  where the ventilation hole  11   a  is located, and the other end extends away from the air inlet mask  10 , as shown in  FIGS. 1-4 . The ventilation pipe  11   b  protrudes from the air inlet mask  10 , so that the air blown from the air supply pipe  20  to the air inlet mask  10  cannot directly enter the ventilation holes  11   a , but needs to pass through the air inlet pipe and then enter the ventilation holes  11   a . This arrangement forces the flow of air entering the air inlet mask  10  to change its direction again, so that the air entering the air inlet mask  10  is uniformly blown to the face. 
     Further, in the embodiment of the present invention, the shape of the ventilation pipe  11   b  is improved. As shown in  FIG. 4 , the diameter of the end of the ventilation pipe  11   b  away from the air inlet mask  10  is less than the diameter of the end close to the air inlet mask  10 . That is, in the embodiment of the present invention, the ventilation pipe  11   b  is provided with a tapered structure having a variable section with gradually increasing diameter. With this arrangement, the wind speed can be stabilized, and the air blown to the human face is more delicate and uniform. 
     In the embodiment of the present invention, only one side of the air inlet mask  10  is provided with the air supply pipe  20  in order to save space. To ensure the uniform flow of the air delivered by the air supply pipe  20 , the first ventilation structure  11  also includes an enclosure  11   c  arranged perpendicular to the body of the air inlet mask  10  and surrounding the plurality of the ventilation holes  11   a  to form an air inlet chamber. With the enclosure  11   c , the air blown from the side cannot directly enter the first ventilation structure  11 . The enclosure  11   c  distributes a portion of the air to the direction of the second ventilation structure  12 , so that both the first ventilation structure  11  and the second ventilation structure  12  can obtain the required air volume, ensuring reliable operation of the mechanism. 
     In addition, in order to ensure uniform distribution of air distributed into the first ventilation structure  11 , the height of the enclosure  11 C close to the air supply pipe  20  is lower than that away from the air supply pipe  20 . With such structural arrangement, the ventilation holes  11   a /ventilation pipe  11   b  far away from the air supply pipe  20  can also obtain uniform wind pressure. In the above embodiment, with the specially structured enclosure  11 C, not only the first ventilation structure  11  and the second ventilation structure  12  obtain uniform wind pressure, but also the interior of the first ventilation structure  11  obtains uniform wind pressure, thus improving the comfort of the human body and reliable operation of the mechanism. 
     In addition, in order to reduce the wind resistance of air entering the enclosure  11 C, in the embodiment of the present invention, as shown in  FIGS. 1 to 4 , the enclosure  11   c  is arranged open at a central position between the upper and lower sides in the height direction of the air inlet mask  10 . 
     In order to improve the fixing strength of the air supply pipe  20 , in the embodiment of the present invention, as shown in  FIG. 1 , the length direction of the air supply pipe  20  is substantially perpendicular to the body of the air inlet mask  10 , the side of the air inlet mask  10  is recessed inward to form a fixing groove  13 , the side wall of the fixing groove  13  is arranged to replica the shape of the side wall where the air supply pipe  20  is fixed. It should be noted here that “substantially perpendicular to” means that when the air inlet mask  10  is worn, the air supply pipe  20  fits to the person&#39;s side face, and one end of the air supply pipe  20  is fixed to the side of the air inlet mask  10 . In this case, the side wall of the air supply pipe  20  also partly fits to the air inlet mask  10 , so that the fixing groove  13  plays a fixing role. 
     In the embodiment of the present invention, the filter screen  30  is detachable for easy replacement. 
     Specifically, the filter screen  30  is fixed in the air inlet mask  10  by fasteners, for example, screws, and can be disassembled with a tool when it needs to be replaced. 
     In a preferred embodiment, as shown in  FIGS. 3-6 , a snap structure  31  is provided at a central position between two ends of the filter screen  30  in the width direction. The first ventilation structure  11   a  is provided with a bayonet  11   d  corresponding to the snap structure  11   a , and the snap structure  11   a  is detachably seated in the bayonet  11   d . The snap structure  31  here is in the form of a snap formed by extending the end of the filter screen forward and then bending it towards the upper and lower sides. In the embodiment of the invention, the filter screen  30  can be made of plastic, so as to allow certain deformation when fixing and removing the filter screen  30 , facilitating the installation and removal of the filter screen  30 . 
     The embodiment of the present invention also provides a headgear as shown in  FIG. 7 , comprising an air supply mechanism with lower air duct described above and a semi-open hood  40 , the semi-open hood  40  including an internal space for at least covering the human face and an observation window  41  at its front end, the air supply mechanism with lower air duct being fixed inside the semi-open hood  40 . 
     The edge of the air inlet mask  10  in the air supply mechanism with lower air duct extends and bends toward the direction of the semi-open hood, so as to form an air inlet chamber between the air inlet mask  10  and the semi-open hood  40 . In the present invention, in order to save materials, the air inlet mask  10  in the air supply mechanism with lower air duct adopts a semi-closed structure, and the air inlet chamber is formed by cooperation of the air inlet mask  10  and the semi-open hood  40 . 
     In the embodiment of the present invention, the semi-open hood  40  means that when a worker wears it, the entire hood is fixed on the front of the worker&#39;s face only by a head-mounted structure at the back of the worker&#39;s head. Through this arrangement, the air entering toward the face through the air inlet mask  10  is directly blown out from the edge of the hood. Therefore, on the one hand, the wearer feels comfortable, on the other hand, it also makes the inlet air blow out along the face to form a barrier to reduce the impact of external air on the face. 
     Of course, it should be pointed out here that the air supply mechanism with lower air duct of the present invention is also applicable to a closed hood. 
     The embodiment of the present invention also provides an electric protective equipment as shown in  FIG. 8 , comprising a headgear described above, a filter-type blower  50 , and a connecting hose  60  connected to the filter-type blower  50  at one end and the air supply pipe  20  in the air supply mechanism with lower air duct at the other end. The filter-type forced blower  50  is known in the prior art, and its detailed structure will not be repeated here. The inhaled air is filtered through the filter  30  and then sent to the headgear. It can be powered by a battery and is easy to carry. The connecting hose  60  is a common connecting pipe with two ends respectively connected to the air supply pipe  20  and the filter-type blower  50 . 
     In the embodiment of the present invention, a wind adjusting mechanism is also provided. When working in cold weather, the hot air breathed by people is more likely to make the observation window of the headgear foggy. To solve this problem, the embodiment of the present invention provides an automatic adjustment mechanism, comprising a pressure sensor fixed inside the filter screen, and a connecting end  21  arranged between the air supply pipe and the connecting hose. The connecting end  21  is provided with a small motor driving the blades to rotate and a controller connected to the pressure sensor and the small motor respectively. When the observation window is not fogged, the blades are free to rotate with the wind direction in the air supply pipe  20  inside the connecting end; when the observation window is fogging, the operator blows toward the pressure sensor to change the parameters of the pressure sensor, so as to trigger the controller to drive the small motor to rotate. The speed of the small motor is greater than the natural rotation speed of the blades, thus the air flow into the headgear is increased. Through such arrangement, the defogging operation can be realized just by the operator blowing air, improving the ease of use. Since the pressure sensor is disposed at the inner edge of the filter screen, the wind blowing toward the inside of the filter screen will not affect the action of the pressure sensor. It should be noted that the pressure sensor is known in the prior art and its detailed principle and structure will not be repeated here. By arranging the sensor at the inner edge of the filter screen  30 , in the embodiment of the present invention, at the upper edge, it is possible to give the operator a feeling of defogging through mouth blowing, which is more intuitive and convenient. Moreover, the connecting end  21  is easy to install and remove, and it is also convenient for functions to be added or removed according to user requirements, improving the applicability of the product. 
     Those skilled in the industry should understand that the present invention is not limited by the foregoing embodiments. The foregoing embodiments and descriptions only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, which fall within the scope of the claimed invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.