Abstract:
A dual action air pump has a body and a piston assembly. The body has an air chamber, an air channel and an elongated hole, which are defined longitudinally in the body parallel to each other. The air chamber has two ends, one of the ends has an outlet with an outlet check valve disk and a secondary inlet with a secondary inlet check valve disk formed therein, the other end has an inlet with an inlet check valve disk formed therein. The air channel has two ends, one of the ends communicates with one end of the air chamber, and the other end has a secondary outlet with a secondary outlet check valve disk formed therewith. The piston assembly is slidably abutting airtightly an inner surface of the air chamber, and can be pull or push to draw air and discharge air simultaneously. Moreover, an air hose used with the dual action air pump can be put into the elongated hole to have a pleasing appearance.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to an inflater, and more particularly to a dual action air pump that simultaneously draws and discharges air into and from the air pump and is convenient to use. 
         [0003]    2. Description of Related Art 
         [0004]    Air pumps fill pneumatic articles such as basketballs and tires with air. With reference to  FIG. 8 , typically, a conventional air pump in accordance with the prior art has a body ( 40 ), a piston assembly ( 50 ) and an air hose ( 60 ). The body ( 40 ) has a chamber ( 41 ), an outlet ( 42 ) and an inlet ( 43 ) defined therein. The chamber ( 41 ) has an inner surface. The piston assembly ( 50 ) is mounted slidably through the inlet ( 43 ) and has a piston rod and a piston. The piston rod is mounted slidably through the inlet ( 43 ) and has an outer end, a handle ( 52 ) and an inner end. The outer end protrudes from the inlet ( 43 ). The handle ( 52 ) is attached securely to the outer end to reciprocate the piston assembly ( 50 ) easily inside the chamber. The inner end is inside the chamber ( 41 ). The piston is attached to the inner end of the piston rod, slidably abuts and forms a seal with the inner surface of the chamber ( 41 ) and has a check valve ( 51 ). The check valve ( 51 ) is mounted through the piston. When the piston assembly ( 50 ) is pulled, the check valve ( 51 ) allows air in the chamber ( 41 ) to move below the piston. The air hose ( 60 ) is normally stored on the body ( 40 ) and has a proximal end ( 61 ), a distal end ( 62 ) and a nozzle. However, storing the air hose ( 60 ) on the body ( 62 ) causes the conventional air pump to have an unsightly appearance. The proximal end ( 61 ) connects to the outlet ( 42 ) of the chamber ( 41 ). The nozzle connects to distal end ( 62 ) of the air hose ( 60 ) and to an inlet of an inflatable object so air can be pumped into the object. When the piston assembly ( 50 ) is pushed, air in the chamber ( 41 ) below the piston is forced through the outlet ( 42 ) and the air hose ( 60 ) into an inflatable object. 
         [0005]    Since air is discharged from the outlet ( 42 ) only when the piston assembly ( 50 ) is pushed, a person has to spend more time to inflate an inflatable article. 
         [0006]    To overcome the shortcomings, the present invention provides a dual action air pump to obviate or mitigate the aforementioned problems. 
       SUMMARY OF THE INVENTION 
       [0007]    The main objective of the present invention is to provide a dual action air pump that draws air into and discharges air from the air pump at the same time. 
         [0008]    Another objective of the present invention is to be able to store an air hose used with the dual action air pump inside the dual action air pump to give the dual action air pump a pleasing appearance. 
         [0009]    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 
         [0010]      FIG. 1  is a perspective view of a dual action air pump in accordance with the present invention; 
           [0011]      FIG. 2  is an exploded perspective view of the dual action air pump in  FIG. 1 ; 
           [0012]      FIG. 3  is a side view in partial section of the dual action air pump in  FIG. 1 ; 
           [0013]      FIG. 4  is a side view in partial section of the dual action air pump in  FIG. 3  rotated slightly to the right; 
           [0014]      FIG. 5  is a cross sectional bottom view of the dual action air pump along line  5 - 5  in  FIG. 3 ; 
           [0015]      FIG. 6  is an operational side view in partial section of the dual action air pump in  FIG. 1  during a downstroke; 
           [0016]      FIG. 7  is an operational side view in partial section of the dual action air pump in  FIG. 1  during an upstroke; and 
           [0017]      FIG. 8  is a side view in partial section of a conventional air pump in accordance with the prior art. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0018]    With reference to  FIGS. 1 to 4 , a dual action air pump in accordance with the present invention comprises a body ( 10 ), an optional air hose ( 30 ) and a piston assembly ( 20 ). 
         [0019]    The body ( 10 ) is elongated and has a rear end, a front end, an air chamber ( 11 ), an air channel ( 12 ), an optional elongated hole ( 13 ), a multi-valve body ( 14 ), a front end cap ( 18 ) and a rear end cap ( 19 ). The air chamber ( 11 ) is defined longitudinally in the body ( 10 ) and has an inner surface, a rear end and a front end. The air channel ( 12 ) is defined longitudinally in the body ( 10 ) parallel to the air chamber ( 11 ) and has a first end and a second end. The first end is formed in the rear end of the body ( 10 ) and communicates with the rear end of the air chamber ( 11 ). 
         [0020]    The elongated hole ( 13 ) is formed longitudinally in the body ( 10 ) parallel to the air chamber ( 11 ) and the air channel ( 12 ) and has an open outer end is formed in the rear end of the body ( 10 ). 
         [0021]    The multi-valve body ( 14 ) is mounted in the front end of the body ( 10 ) and has a base ( 143 ), a chamber sleeve ( 140 ) and a channel sleeve ( 142 ). 
         [0022]    The base ( 143 ) is formed on the front end of the multi-valve body ( 14 ) and has a division wall and a discharge chamber. 
         [0023]    The chamber sleeve ( 140 ) is formed with and protrudes from the division wall of the base ( 143 ), is connected with an airtight seal to the air chamber ( 11 ) and has a front end, a sidewall, a downstroke outlet ( 15 ), a downstroke outlet check valve disk ( 150 ), an upstroke inlet ( 16 ) and an upstroke inlet check valve disk ( 160 ). The front end of the chamber sleeve ( 140 ) is formed integrally with the division wall in the base ( 143 ). With further reference to  FIG. 5 , the downstroke outlet ( 15 ) is formed through the front end of the chamber sleeve ( 140 ) and the division wall of the base ( 143 ) and communicates with the air chamber ( 11 ) and the outer environment via the discharge chamber in the base ( 143 ) and the discharge hole ( 181 )(with reference to  FIG. 4 ). The downstroke outlet check valve disk ( 150 ) is resilient and is mounted securely on the front end of the chamber sleeve ( 140 ) inside the discharge chamber in the base ( 143 ), covers the downstroke outlet ( 15 ) to keep air from flowing into the air chamber ( 11 ) during an upstroke and allow air inside the air chamber ( 11 ) to flow out from the downstroke outlet ( 15 ) during a downstroke. The upstroke inlet ( 16 ) is formed on the sidewall of the chamber sleeve ( 140 ), communicates with the air chamber ( 11 ) and the outer environment via the discharge chamber in the base ( 143 ) and the discharge hole ( 181 )(with reference to  FIG. 4 ). The upstroke inlet check valve disk ( 160 ) is resilient and is mounted securely on the upstroke inlet on the sidewall of the chamber sleeve ( 140 ), covers the upstroke inlet ( 16 ) to allow ambient air to enter the air chamber ( 11 ) during an upstroke and keep air inside the air chamber ( 11 ) from flowing out from the upstroke inlet ( 16 ) during a downstroke. 
         [0024]    The channel sleeve ( 142 ) is formed with and protrudes from the division wall of the base ( 143 ) parallel to the chamber sleeve ( 140 ), is connected with an airtight seal to the second end of the air channel ( 12 ), has a front end, an upstroke outlet ( 17 ) and an upstroke outlet check valve disk ( 170 ). The front end of the channel sleeve ( 142 ) is formed integrally with the division wall in the base ( 143 ). The upstroke outlet ( 17 ) is formed through the front end of the channel sleeve ( 142 ) and the division wall of the base ( 143 ) and communicates with the air channel ( 12 ) and the outer environment via the discharge chamber in the base ( 143 ) and the discharge hole ( 181 )(with reference to  FIG. 4 ). The upstroke outlet check valve disk ( 170 ) is resilient and is mounted securely on the upstroke outlet ( 17 ) on the front end of the channel sleeve ( 142 ) inside the discharge chamber in the base ( 143 ), covers the upstroke outlet ( 17 ) to keep air from flowing into the air channel ( 12 ) during a downstroke and allow air inside the air channel ( 12 ) to flow out from the upstroke outlet ( 17 ) during an upstroke. 
         [0025]    The front end cap ( 18 ) is mounted on the front end of the body ( 10 ), holds the multi-valve body ( 14 ) and has a front end, a space ( 180 ), a discharge hole ( 181 ) and multiple air holes ( 182 ). The space ( 180 ) is defined in the front end cap ( 18 ), holds the multi-valve body ( 14 ) and has a sidewall. The sidewall is mounted around the multi-valve body ( 14 ) and forms an airtight seal. The discharge hole ( 181 ) is formed through the front end of the front end cap ( 18 ), communicates with the downstroke outlet ( 15 ) and the upstroke outlet ( 17 ) and may have an inner thread. The air holes ( 182 ) are formed through the sidewall and communicate with the upstroke inlet ( 16 ) and the outer environment to allow ambient air to pass into the chamber sleeve ( 140 ) and the air chamber ( 11 ) during an upstroke. 
         [0026]    The rear end cap ( 19 ) is mounted on the rear end of the body ( 10 ) and has a cavity ( 190 ), a downstroke inlet ( 192 ), a downstroke inlet check valve disk ( 194 ), a through hole ( 191 ), an optional air hose hole ( 193 ) and an optional storage plug ( 195 ). The cavity ( 190 ) covers the rear end of the air chamber ( 11 ) and the first end of the air channel ( 12 ), so the air chamber ( 11 ) communicates with the air channel ( 12 ). The downstroke inlet ( 192 ) is formed through the rear end cap ( 19 ). The downstroke inlet check valve disk ( 194 ) is resilient and is mounted securely on the downstroke inlet ( 192 ) in the cavity ( 190 ), covers the downstroke inlet ( 192 ) to allow ambient air to enter the air chamber ( 1 ) and the air channel ( 12 ) during a downstroke and keep air inside the air chamber ( 11 ) and the air channel ( 12 ) from flowing out from the downstroke inlet ( 192 ) during an upstroke. The through hole ( 191 ) is formed through the rear end cap ( 19 ) coaxially relative to the air chamber ( 11 ) of the body ( 10 ). The air hose hole ( 193 ) is formed through rear end cap ( 19 ) and is aligned with and corresponds to the elongated hole ( 13 ) in the body ( 10 ). The storage plug ( 195 ) corresponds to and is mounted detachably in the air hose hole ( 193 ). 
         [0027]    The air hose ( 30 ) connects to the discharge hole ( 181 ) in the front end cap ( 18 ) to an inflatable object and to direct air from the dual action air pump to the inflatable object, is stored in the elongated hole ( 13 ) in the body ( 10 ) and has a proximal end ( 31 ), a distal end ( 32 ) and an optional needle nozzle ( 33 ). The proximal end ( 31 ) may have an external thread. The external thread screws into the internal thread in the discharge hole ( 181 ) to connect the air hose ( 30 ) to the dual action air pump. The needle nozzle ( 33 ) is attached to the distal end of the air hose ( 30 ) and plugs into an inflatable object. 
         [0028]    The piston assembly ( 20 ) compresses air in the air chamber ( 11 ), forces the air through the discharge hole ( 181 ) in the front end cap ( 18 ) and comprises a piston rod ( 21 ), a piston ( 22 ), an optional seal assembly ( 23 ) and an optional handle ( 24 ). The piston rod ( 21 ) is mounted slidably in the through hole ( 191 ) in the rear end cap ( 19 ) and has an outer end and an inner end. The outer end protrudes from the through hole ( 191 ). The inner end is inside the air chamber ( 11 ). The piston ( 22 ) is mounted slidably in the air chamber ( 11 ), compresses air in the air chamber ( 11 ), is attached securely to the inner end of the piston rod ( 21 ) and has an outer edge, an optional annular groove and an optional seal ( 220 ). The annular groove is formed in the outer edge of the piston ( 22 ). The seal ( 220 ) is mounted in the annular groove, abuts the inner surface of the air chamber ( 11 ) to form an airtight seal and may be an O-ring. The seal assembly ( 23 ) is mounted around the piston rod ( 21 ) inside the rear end cap ( 19 ) and connects to the rear end cap ( 19 ) to seal the through hole ( 191 ) in the rear end cap ( 19 ) to keep air compressed inside the air chamber ( 11 ) and the air channel ( 12 ) from escaping around the piston rod ( 21 ) and through the through hole in the rear end cap ( 19 ). The handle ( 24 ) is mounted securely on the outer end of the piston rod ( 21 ) to allow a person to push or pull the piston assembly ( 20 ) easily and conveniently. 
         [0029]    With further reference to  FIG. 6 , pushing the piston assembly ( 20 ) makes the piston ( 22 ) slide in the air chamber ( 11 ) toward the front end of the air chamber ( 11 ), and air compressed inside the air chamber ( 11 ) between the piston ( 22 ) and the front end of the air chamber ( 11 ) pushes the outlet check valve disk ( 150 ) aside and is discharged through the discharge hole ( 181 ). Simultaneously, air pressure in the air chamber ( 11 ) between the piston ( 22 ) and the rear end of the air chamber ( 11 ) and in the air channel ( 12 ) decreases, and relatively higher pressure ambient air pushes through the downstroke inlet ( 192 ) past the downstroke inlet check valve disk ( 194 ) and refills the air chamber ( 11 ). 
         [0030]    With further reference to  FIG. 7 , subsequently pulling the piston assembly ( 20 ) makes the piston ( 22 ) slide toward the rear end of the air chamber ( 11 ), and air compressed inside the air chamber ( 11 ) and the air channel ( 12 ) between the piston ( 22 ) and the front end of the air channel ( 12 ) pushes the upstroke outlet check valve disk ( 170 ) aside and is discharged through the discharge hole ( 181 ). Simultaneously, air pressure in the air chamber ( 11 ) between the piston ( 22 ) and the front end of the air chamber ( 11 ) decreases, and relatively higher pressure ambient air from the air holes ( 182 ) pushes through the upstroke inlet ( 16 ) past the upstroke inlet check valve disk ( 160 ) and refills the air chamber ( 11 ). 
         [0031]    Accordingly, the dual action air pump in accordance with the present invention draws air and discharges air at the same time, such that less time is required to inflate inflatable articles. Furthermore, the air hose ( 30 ) is stored in the elongated hole ( 13 ) and does not detract from the appearance of the dual action air pump. 
         [0032]    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.