Patent Publication Number: US-2010126509-A1

Title: Air recycling device for auxiliary respiration apparatus

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an air recycling device for auxiliary respiration apparatus, and more particularly to an air recycling device that recycles expired air for user to inhale again so the air tank can be used longer. 
     2. Description of Related Art 
     Beach actions are popular with people in summer time, especially diving. Diving could be snorkeling or scuba diving. Snorkeling is an action of swimming at the surface of water so an air tank is not required. Scuba diving is an action of swimming underwater so divers must carry air tanks. 
     The air tank stores high pressure air and supplies the air to the diver with a diving regulator. The diving regulator is used to regulate the pressure of the air in the air tank to allow the diver breathing as usual on land. A diving regulator comprises a first stage and a second stage. The first stage communicates with the air tank. The second stage connects to a mouthpiece to allow the diver to inhale air. The second stage further has a deflator to exhaust expired air. 
     Although oxygen gas constitutes 21% of the volume of air, a person only requires 4% to 6% oxygen gas in each respiration, and the remaining oxygen gas will be expired with carbon dioxide. However, as the water pressure increases one atmosphere per 10 meters of depth under water, the percentage of air of the oxygen gas will double to 0.42 absolute atmosphere (ata). Because the diver requires the same quantity of oxygen gas, the remaining oxygen gas will be wasted and the utility rate of the oxygen gas is low. Therefore, the available duration of the air tank is reduced. 
     Furthermore, firemen use the similar auxiliary respiration apparatus, and the utility rate of the oxygen gas is also low even though the percentage of air of the oxygen gas does not vary in the scene of a fire. 
     To overcome the shortcomings, the present invention provides an air recycling device for auxiliary respiration apparatus to mitigate or obviate the aforementioned problems. 
     SUMMARY OF THE INVENTION 
     The main objective of the invention is to provide an air recycling device for auxiliary respiration apparatus that recycles expired air for user to inhale again so the available duration of the air tank will be extended. 
     The air recycling device in accordance with the present invention comprises a casing, an air gather assembly, a valve assembly and a pressure switch unit. The casing has a regulator connector and an air feeder. The air gather assembly communicates with the casing. The valve assembly selectively blocks the communication either between the air feeder and the air gather assembly or between the regulator connector and the air feeder. In the moment between inhaling and exhaling, the pressure switch unit drives the valve assembly to block the communication between the air feeder and the regulator connector to gather the air expired from the user into the air gather assembly. When the user inhales again, the user inhales the air in the air gather assembly. The subsequently expired air flows through the regulator connector to a diving regulator. Because the air expired by the diver is recycled, the consumption of the air in the air tank is reduced. Available duration of the air tank will be extended. 
     Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a rear perspective view of an air recycling device in accordance with the present invention; 
         FIG. 2  is a rear perspective view in cross section of the air recycling device in  FIG. 1 ; 
         FIG. 3  is a side view in cross section of the air recycling device in  FIG. 1 ; 
         FIG. 4  is a rear view of the air recycling device; 
         FIG. 5  is a rear perspective view in partial section of the air recycling device in  FIG. 1 ; 
         FIG. 6  is a side view of the air recycling device; 
         FIG. 7  is another rear perspective view in partial section of the air recycling device in  FIG. 1 ; 
         FIG. 8  is a side perspective view of part of a valve assembly in the air recycling device; 
         FIG. 9  is a rear view in cross section of the air recycling device; 
         FIG. 10  is a rear view in partial section of the air recycling device in  FIG. 5 ; 
         FIG. 11  is another rear view in cross section of the air recycling device, showing an operation of a pressure switch unit and the valve assembly. 
         FIG. 12  is another rear view in cross section of the air recycling device, showing another operation of a pressure switch unit and the valve assembly; 
         FIG. 13  is a perspective view of part of the valve assembly, showing an operation of a plate and a driving stick; and 
         FIG. 14  is a side view in cross section of the air recycling device in  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT 
     With reference to  FIG. 1 , an air recycling device for auxiliary respiration apparatus in accordance with the present invention may be used to diver auxiliary respiration apparatus. The air recycling device comprises a casing ( 10 ), an air gather assembly, a valve assembly and a pressure switch unit. 
     With further reference to  FIGS. 2 and 3 , the casing ( 10 ) has a regulator connector ( 11 ), an air feeder ( 12 ) and an air exchange hole ( 13 ) and may comprise a transmission room ( 101 ), a valve room ( 102 ), two partitions ( 102   a ), a pressure detection room ( 103 ) and a drive room ( 104 ). 
     The regulator connector ( 11 ) is used to communicate with a second stage of a diving regulator. 
     The air feeder ( 12 ) provides air to a diver and can be held in the diver&#39;s mouth with a mouthpiece. 
     The valve room ( 102 ) is adjacent to the transmission room ( 101 ) and communicates with the regulator connector ( 11 ), the air feeder ( 12 ) and the air exchange hole ( 13 ). 
     The partitions ( 102   a ) are mounted in the valve room ( 102 ). One of the partitions ( 102   a ) is mounted between the regulator connector ( 11 ) and the air feeder ( 12 ), and the other partition ( 102   a ) is mounted between the air feeder ( 12 ) and the air exchange hole ( 13 ). Each partition ( 102   a ) has a notch ( 102   b ). 
     The pressure detection room ( 103 ) is adjacent to the valve room ( 102 ), communicates with the valve room ( 102 ) and the air feeder ( 12 ) and has an inner surface. 
     The drive room ( 104 ) is adjacent to the pressure detection room ( 103 ). 
     With further reference to  FIG. 4 , the air gather assembly connects to and communicates with the air exchange hole ( 13 ) and may comprise an air gather tube ( 21 ), two pipes ( 22 ), a first buffer bag ( 23 ), a carbon-dioxide filter ( 24 ) and a second buffer bag ( 25 ). 
     The air gather tube ( 21 ) is a hollow cylinder and has two openings ( 211 ) and an air exchange connector ( 212 ). The air exchange connector ( 212 ) is connected to and communicates with the air exchange hole ( 13 ). 
     The pipes ( 22 ) are connected respectively to and communicate with the openings ( 211 ) of the air gather tube ( 21 ). 
     The first buffer bag ( 23 ) connects to and communicates with one of the pipes ( 22 ) to temporarily store the air expired by the diver. 
     The carbon-dioxide filter ( 24 ) communicates with the first buffer bag ( 23 ) to filter the carbon-dioxide of the expired air from the first buffer bag ( 23 ). 
     The second buffer bag ( 25 ) connects to and communicates with the other pipe ( 22 ) and the carbon-dioxide filter ( 24 ) to temporarily store the filtered air. The filtered air will be provided to the diver. 
     With further reference to  FIGS. 5 to 7 , the valve assembly is mounted in the casing ( 10 ) and selectively blocks the communication either between the air feeder ( 12 ) and the air exchange hole ( 13 ) or between the regulator connector ( 11 ) and the air feeder ( 12 ). The valve assembly may comprise a resilience wheel ( 31 ), a leaf spring ( 32 ), a transmission wheel ( 33 ), a first spur gear ( 331 ), a manual revolving stick ( 332 ), a shaft ( 34 ), a second spur gear ( 341 ), a first bevel gear ( 342 ), a plate ( 35 ), a second bevel gear ( 352 ) and a driving stick ( 36 ). 
     The resilience wheel ( 31 ) is rotatably mounted in the transmission room ( 101 ) of the casing ( 10 ). 
     The leaf spring ( 32 ) is mounted in the transmission room ( 101 ) of the casing ( 10 ), is wound around the resilience wheel ( 31 ) and has two ends. One of the ends of the leaf spring ( 32 ) is connected to the resilience wheel ( 31 ). 
     The transmission wheel ( 33 ) is rotatably mounted in the transmission room ( 101 ) of the casing ( 10 ), is connected to the other end of the leaf spring ( 32 ) and has an axis. 
     The first spur gear ( 331 ) is mounted around the axis of the transmission wheel ( 33 ) and is rotatable with the transmission wheel. 
     The manual revolving stick ( 332 ) is connected to the axis of the transmission wheel ( 33 ) and protrudes through the casing ( 10 ) to allow the diver to rotate the transmission wheel ( 33 ) manually and wind the leaf spring ( 32 ) on the transmission wheel ( 33 ). Therefore, the resilience of the leaf spring ( 32 ) will intend to reverse the transmission wheel ( 33 ). 
     The shaft ( 34 ) is mounted over the transmission room ( 101 ), the valve room ( 102 ), the pressure detection room ( 103 ) and drive room ( 104 ) and has two ends. One of the ends is in the transmission room ( 101 ). The other end is in the drive room ( 104 ). 
     The second spur gear ( 341 ) is mounted on the end of the shaft ( 34 ) in the transmission room ( 101 ) and is engaged with the first spur gear ( 331 ). 
     The first bevel gear ( 342 ) is mounted on the end of the shaft ( 34 ) in the drive room ( 104 ). 
     The plate ( 35 ) is rotatably mounted in the drive room ( 104 ) of the casing ( 10 ) and has a front, a rear, a ratchet wheel ( 351 ) and multiple teeth ( 353 ). The ratchet wheel ( 351 ) is rotatably mounted on the front of the plate ( 35 ) and has multiple ratchets. The teeth ( 353 ) are formed around and protrudes from the rear of the plate ( 35 ), and an odd number of the teeth ( 353 ) is implemented. Preferably, seventeen teeth ( 353 ) may be implemented. 
     The second bevel gear ( 352 ) is rotatably connected to the plate ( 35 ) and is engaged with the first bevel gear ( 342 ). 
     The driving stick ( 36 ) is mounted over the transmission room ( 101 ), the valve room ( 102 ), the pressure detection room ( 103 ) and the drive room ( 104 ) in the casing ( 10 ). With further reference to  FIG. 8 , the driving stick ( 36 ) has a surface, a first protrusion ( 361 ), a second protrusion ( 362 ) and a valve ( 363 ). 
     The first protrusion ( 361 ) and the second protrusion ( 362 ) protrude from the surface of the driving stick ( 36 ) and correspond to the teeth ( 353 ) on the plate ( 35 ). The first and the second protrusions ( 361 ,  362 ) are alternatively between two adjacent teeth ( 353 ) and contacting with one of the teeth ( 353 ). For example, when the first protrusion ( 361 ) is between two adjacent teeth ( 353 ), the second protrusion ( 362 ) contacts with one of the teeth ( 353 ), and vice versa. 
     The valve ( 363 ) is formed on the driving stick ( 36 ), corresponds to the notches ( 102   b ) of the partitions ( 102   a ) and selectively blocks the corresponding notch ( 102   b ) to disconnect the communication either between the air feeder ( 12 ) and air exchange hole ( 13 ) or between the regulator connector ( 11 ) and the air feeder ( 12 ). 
     The pressure switch unit is mounted in the casing ( 10 ) and is connected to the valve assembly to drive the valve assembly communicating the air feeder ( 12 ) with either the regulator connector ( 11 ) or the air exchange hole ( 13 ) in a cycle made by the pressure in the casing ( 10 ) dropping and subsequently raising. With further reference to  FIGS. 9 and 10 , the pressure switch unit may comprise a film ( 41 ), a retaining wall ( 42 ), a linkage assembly, a compression spring ( 44 ), a pivot ( 483 ) and a fastener. 
     The film ( 41 ) is mounted in the pressure detection room ( 103 ) of the casing ( 10 ). 
     The retaining wall ( 42 ) protrudes horizontally from the inner surface of the pressure detection room ( 103 ). 
     The linkage assembly is mounted over the pressure detection room ( 103 ) and the drive room ( 104 ) of the casing ( 10 ) and connects to the film ( 41 ). 
     The compression spring ( 44 ) winds around the linkage assembly and sustains between the film ( 41 ) and the retaining wall ( 42 ). 
     The pivot ( 483 ) connects pivotally to the linkage assembly in the drive room ( 104 ). 
     The fastener is mounted in the drive room ( 104 ) of the casing ( 10 ) and has a first pawl ( 481 ) and a second pawl ( 482 ). 
     The first pawl ( 481 ) and the second pawl ( 482 ) connect pivotally to the pivot ( 483 ) and are pulled by the moving linkage assembly to alternatively engage with the ratchet wheel ( 351 ). 
     Furthermore, the linkage assembly may comprise a first linkage ( 43 ), a second linkage ( 45 ), a third linkage ( 46 ) and a fourth linkage ( 47 ). 
     The first linkage ( 43 ) is mounted in the pressure detection room ( 103 ) of the casing ( 10 ), is wound around by the compression spring ( 44 ) and has a top end and a bottom. The top end is connected to the film ( 41 ), and the bottom end protrudes through the retaining wall ( 42 ). 
     The second linkage ( 45 ) is mounted in the pressure detection room ( 103 ) of the casing ( 10 ) and has a first end and a second end. The first end of the second linkage ( 45 ) connects pivotally to the bottom end of the first linkage ( 43 ). 
     The third linkage ( 46 ) is mounted over the pressure detection room ( 103 ) and the drive room ( 104 ) of the casing ( 10 ) and has a first end and a second end. The first end of the third linkage ( 46 ) connects pivotally to the second end of the second linkage ( 45 ). 
     The fourth linkage ( 47 ) is mounted in the drive room ( 104 ) of the casing ( 10 ) and has a first end and a second end. The first end of the fourth linkage ( 47 ) connects pivotally to the second end of the third linkage ( 46 ). The second end of the fourth linkage ( 47 ) connects pivotally to the pivot ( 483 ). 
     Operations of the above-mentioned air recycling device are described as follows. 
     When the diver rotates the transmission wheel ( 33 ) manually over the manual revolving stick ( 332 ) to wind the leaf spring ( 32 ) on the transmission wheel ( 33 ) before starting diving, the resilience of the leaf spring ( 32 ) intends to reverse the transmission wheel ( 33 ) to turn the shaft ( 34 ) through the first and the second spur gears ( 331 ,  341 ). Once the shaft ( 34 ) turns, the plate ( 35 ) will be driven by the shaft ( 34 ) over the first and the second bevel gears ( 342 ,  352 ). However, because the first pawl ( 481 ) engages with the ratchet wheel ( 351 ) on the plate ( 35 ) initially and stops the plate ( 35 ) from turning, the un-rotatable plate ( 35 ) prohibits the shaft ( 34 ), the transmission wheel ( 33 ) and the resilience wheel ( 31 ) from turning even though the leaf spring ( 32 ) has applied the reversing force to the transmission wheel ( 33 ). 
     When the diver dives and inhales from the air feeder ( 12 ), the pressure in the valve room ( 102 ) drops. Because the pressure detection room ( 103 ) communicates with the valve room ( 102 ), the pressure in the pressure detection room ( 103 ) also drops. The film ( 41 ) will deform and be drawn toward the air feeder ( 12 ) by the decreased pressure in the pressure detection room ( 103 ). With further reference to  FIG. 11 , the film ( 41 ) deformed toward the air feeder ( 12 ) results in that the first linkage ( 43 ) moves downward to compress the compression spring ( 44 ). The first linkage ( 43 ) pulls the second linkage ( 45 ) to move, the second linkage ( 45 ) pulls the third linkage ( 46 ) moving, and the third linkage ( 46 ) pulls the fourth linkage ( 47 ) moving. The moving fourth linkage ( 47 ) and the fastener subsequently turn around the pivot ( 483 ) so the second pawl ( 482 ) of the fastener engages with the ratchet wheel ( 351 ) on the plate ( 35 ). Because the second pawl ( 482 ) is shorter than the first pawl ( 481 ), the first pawl ( 481 ) releases the ratchet wheel ( 351 ) on the plate ( 35 ) after the second pawl ( 482 ) engages with the ratchet wheel ( 351 ). Therefore, the plate ( 35 ) is still stopped by the fastener. 
     With further reference to  FIG. 12 , in the moment between inhaling and exhaling, the pressure in the valve room ( 102 ) and the pressure detection room ( 103 ) raise. The film ( 41 ) resiles to its original shape because of the resilience of the compression spring ( 44 ). The resiled film ( 41 ) pulls the first linkage ( 43 ) to move upward. The moved first linkage ( 43 ) drives the second linkage ( 45 ), the third linkage ( 46 ) and the fourth linkage ( 47 ) to move. The fastener turns at the pivot ( 483 ) when the fourth linkage ( 47 ) moves to switch the first pawl ( 481 ) to engage with the ratchet wheel ( 351 ). Because the second pawl ( 482 ) is shorter than the first pawl ( 481 ), the second pawl ( 482 ) releases the ratchet wheel ( 351 ) before the first pawl ( 481 ) engages with the ratchet wheel ( 351 ). The fastener does not stop the plate ( 35 ) from turning so the turning plate ( 35 ) results in that the shaft ( 34 ), the transmission wheel ( 33 ) and the resilience wheel ( 31 ) are turned by the resilience of the leaf spring ( 32 ). The first pawl ( 481 ) subsequently engages with the next ratchet of the ratchet wheel ( 351 ) to stop the plate ( 35 ) from keep turning. 
     With reference to  FIG. 13 , furthermore, when the plate ( 35 ) turns, one of the teeth ( 353 ) on the rear of the plate ( 35 ) adjacent to the first protrusion ( 361 ) pushes the first protrusion ( 361 ) upward to turn the driving stick ( 36 ). After the plate ( 35 ) turns and subsequently stops, the first protrusion ( 361 ) contacts with the adjacent tooth ( 353 ), and the second protrusion ( 362 ) is between two adjacent teeth ( 353 ). In the meantime, the turning driving stick ( 36 ) moves the valve ( 363 ) upward. 
     Therefore, with further reference to  FIG. 14 , the valve ( 363 ) is switched to cover the notch ( 102   b ) between the air feeder ( 12 ) and the regulator connector ( 11 ) to blocks their communications. Consequently, air exhaled by the diver will flow into the air gather tube ( 20 ). 
     When the diver inhales again, the diver inhales the air in the air gather assembly. The pressure in the valve room ( 102 ) drops again, and the film ( 41 ) deforms again. The deformed film ( 41 ) results in that the first linkage ( 43 ), the second linkage ( 45 ), the third linkage ( 46 ) and the fourth linkage ( 47 ) move. The moved fourth linkage ( 47 ) and the fastener subsequently turn around the pivot ( 483 ) to move the second pawl ( 482 ) of the fastener to engage with the ratchet wheel ( 351 ) on the plate ( 35 ). The first pawl ( 481 ) released the ratchet wheel ( 351 ) after the second pawl ( 482 ) engages with the ratchet wheel ( 351 ) because the second pawl ( 482 ) is shorter than the first pawl ( 481 ). The plate ( 35 ) is still stopped by the fastener. 
     In the moment between inhaling and exhaling, the pressure in the valve room ( 102 ) and the pressure detection room ( 103 ) raise. The film ( 41 ) resiles to its original shape because of the resilience of the compression spring ( 44 ). The resiled film ( 41 ) pulls the first linkage ( 43 ), the second linkage ( 45 ), the third linkage ( 46 ) and the fourth linkage ( 47 ) to move. The fastener subsequently turns at the pivot ( 483 ) so the first pawl ( 481 ) will engage with the ratchet wheel ( 351 ) again. The second pawl ( 482 ) releases the ratchet wheel ( 351 ) before the first pawl ( 481 ) engages with the ratchet wheel ( 351 ) so the plate ( 35 ) turns. The turning plate ( 35 ) results in that the shaft ( 34 ), the transmission wheel ( 33 ) and the resilience wheel ( 31 ) are turned by the resilience of the leaf spring ( 32 ). The first pawl ( 481 ) subsequently engages with the next ratchet of the ratchet wheel ( 351 ) to stop the plate ( 35 ) from keep turning. 
     When the plate ( 35 ) turns, one of the teeth ( 353 ) on the rear of the plate ( 35 ) adjacent to the second protrusion ( 362 ) pushes the second protrusion ( 362 ) downward to turn the driving stick ( 36 ). After the plate ( 35 ) turns and subsequently stops, the second protrusion ( 362 ) contacts with the adjacent tooth ( 353 ), and the first protrusion ( 361 ) is between two adjacent teeth ( 353 ). The turning driving stick ( 36 ) also moves the valve ( 363 ) downward. 
     Therefore, the valve ( 363 ) is switched to cover the notch ( 102   b ) between the air feeder ( 12 ) and the air exchange hole ( 13 ) to block their communications. Consequently, air exhaled by the diver will flow through the regulator connector ( 11 ) to the diving regulator. 
     Because the air expired by the diver is recycled, the consumption of the air in the air tank is reduced. Available duration of the air tank will be extended. Furthermore, the above-mentioned air recycling device may be used to the fireman auxiliary respiration apparatus. 
     Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only. Changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.