Patent Publication Number: US-2021180585-A1

Title: Mini air pump

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to a pump, especially to a mini air pump. 
     2. Description of Related Art 
     In a conventional mini air pump in which valves and a pump body are integrated, relief flows flow into the sprig chamber and directly act on the spring. Under the influence of air pressure, the spring can&#39;t be set up stably in the spring chamber and this causes changes in the abutting force applied to the relief valve by the spring. Thereby accurate actuation of the relief valve within preset air pressure is unable to be ensured. 
     Moreover, buzzing noises of the air flow are usually generated when relief flows are directly released to the atmosphere. Thus the operating noise of the mini air pump is increased to a certain extent. 
     Thus there is room for improvement and there is a need to provide a novel mini air pump which solves the above problems to some degree. 
     SUMMARY OF THE INVENTION 
     Therefore it is a primary object of the present invention to provide a mini air pump in which a relief valve actuates accurately for precise regulation of air pressure in objects to be inflated and overpressure protection of the objects to be inflated. 
     The present invention provides a mini air pump which includes: a diaphragm which includes a plurality of bladders on one side of the diaphragm and each of the bladders having a bladder cavity with an opening toward the other side of the diaphragm; a bladder base which includes a plurality of air inlet channels and a plurality of bladder holes penetrating the bladder base in thickness direction while the diaphragm is attached to the bladder base and the bladders are passed through the bladder holes correspondingly; a pump body which includes a valve seat provided with a plurality of exhaust channels and stacked over the diaphragm, a pump cover stacked on the valve sea, an exhaust chamber and a spring chamber separated from each other and constructed by the valve seat and the pump cover, and a return channel constructed by the valve seat, the diaphragm, and the bladder base and communicating the valve seat, the diaphragm, and the bladder base with one another; the exhaust channels communicating with the bladder cavity while return channel communicating with the air inlet channel but not communicating with the spring chamber; an air inlet valve disposed in flowing direction of air in the air inlet channel and used for communicating the bladder cavity with the air inlet channel in one-way manner; an air outlet valve arranged in flowing direction of air in the exhaust channel and used for communicating the exhaust chamber with the bladder cavity in one-way manner; a relief valve mounted in the exhaust chamber for selectively communicating the return channel with the exhaust chamber; and a preload member mounted in the spring chamber and having at least one spring which applies a preload to the relief valve. 
     The spring chamber is disconnected from both the exhaust chamber and the return channel to prevent the exhaust flow or the return flow from flowing into the spring chamber. Thus the spring is quite stably positioned in the spring chamber to ensure the abutting force applied to the relief valve by the spring remains the same and the relief valve can act more accurately. Therefore the stability of the mini air pump during blowing up of the objects to be inflated is increased. 
     Implementation of the present invention produces advantageous effects which are described in detail as follows. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein: 
         FIG. 1  is an explosive view of an embodiment according to the present invention; 
         FIG. 2  is a sectional view of an embodiment according to the present invention; 
         FIG. 3  is a sectional view of an embodiment viewed from another angle according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The preferred embodiments of the present invention are described in detail as follows and the embodiments are shown in the figures, wherein the same or similar reference numerals are used to refer to the same or similar elements having the same or similar functions. The embodiments described with reference to the figures are exemplary and explanatory only and are not restrictive of the invention. 
     Refer to  FIG. 1 ,  FIG. 2  and  FIG. 3 , a mini air pump  100  according to the present invention includes a diaphragm  10 , a bladder base  20 , a pump body  30 , an air inlet valve  40 , an air outlet valve  51 , a relief valve  52  and a preload member  70 . 
     With reference of  FIG. 1 ,  FIG. 2  and  FIG. 3 , a plurality of bladders  11  are disposed on one side of the diaphragm  10  (such as a lower side in  FIG. 2 ) and each bladder  11  includes a bladder cavity  111  with an opening toward the other side of the diaphragm  10  (such as an upper side in  FIG. 2 ). The diaphragm  10  is a flexible member made of materials such as rubber. The volume of the bladder cavity  111  can be increased or decreased due to the bladder  11  being squeezed or stretched by an external force so as to pump air/gas in/out. 
     The bladder base  20  is used for supporting the diaphragm  10  and composed of a plurality of bladder holes  21  and a plurality of air inlet channels  22 . The bladder holes  21  are penetrating the bladder base  20  in the thickness direction of the bladder base  20 . The diaphragm  10  is attached to the bladder base  20  and each of the bladders  11  is inserted through one of the bladder holes  21  correspondingly. 
     The air inlet channels  22  are used for delivering air/gas to the bladder cavity  111 . The air inlet channel  22  can not only be disposed on the bladder base  20 . For example, a part of the air inlet channel  22  is formed on the bladder base  20  while the rest part of the air inlet channel  22  is formed on the pump body  30 . In this case, intake air flow first is passed through the air inlet channel  22  of the bladder base  20 , moved upward through the air inlet channel  22  of pump body  30  and then turned downward to be sucked into the bladder cavity  111 . In this embodiment, the flow noise is reduced by the air flow travelling further. 
     In order to prevent backflow of the air in the bladder cavity  111 , the air inlet valve  40  is disposed in the flowing direction of the air in the air inlet channel  22  and used for communicating the bladder cavity  111  with the air inlet channel  22  in one-way manner. More specifically, the air inlet valve  40  is open and the air is passed through the air inlet channel  22  to be delivered into the bladder cavity  111  when the bladder cavity  111  is stretched to increase the volume thereof and draw the air in. While the bladder cavity  111  is squeezed to decrease the volume thereof and exhaust the air, the air inlet valve  40  is closed. Thus arrangement of the air inlet valve  40  in the flowing direction of the intake flow is to prevent the air flow from flowing back. 
     Moreover, the pump body  30  consists of a valve seat  31  and a pump cover  32  stacked on each other. The valve seat  31  is stacked over the diaphragm  10 . The pump body  30  is generally made of plastic which is easy to mold. 
     More specifically, as shown in  FIG. 2  and  FIG. 3 , an exhaust chamber  33  and a spring chamber  34 , separated from each other, are constructed by the valve seat  31  and the pump cover  32 . The valve seat  31  is provided with a plurality of exhaust channels  311  which are communicating with the bladder cavities  111 . When the bladder cavity  111  is compressed, the air in the bladder cavity  111  is flowing into the exhaust chamber  33  through the exhaust channel  311  while exhaust flow will not flow into the spring chamber  34 . 
     In order to prevent air flow in the exhaust chamber  33  from returning, the air outlet valve  51  is disposed in the flowing direction of the air in the exhaust channel  311  and used for communicating the bladder cavity  111  with the exhaust chamber  33  in one-way manner. More concretely, the air outlet valve  51  is closed and the air is delivered to the bladder cavity  111  through the air inlet channel  22  when the bladder cavity  111  is stretched to increase the volume thereof and draw the air in. While the bladder cavity  111  is squeezed to decrease the volume thereof and exhaust the air, the air outlet valve  51  is open and the air flow moves out through the exhaust channel  311 . Moreover, the air outlet valve  51  is open when the air inlet valve  40  is closed while the air outlet valve  51  is closed once the air inlet valve  40  is open. Thereby the air is drawn into the bladder cavity  111  and exhausted from the bladder cavity  111  repeatedly. 
     A return channel  35  is constructed by the valve seat  31 , the diaphragm  10 , and the bladder base  20  and communicating the valve seat  31 , the diaphragm  10 , and the bladder base  20  with one another. The return channel  35  is communicating with the air inlet channel  22  but is not communicating with the spring chamber  34 . The relief valve  52  is mounted in the exhaust chamber  33  for selectively communicating the exhaust chamber  33  with the return channel  35 . When the mini air pump  100  is used to blow up objects users intend to inflate and the pressure in the object is over the preset value, the relief valve  52  is open and air in the exhaust chamber  33  is output through the return channel  35  and returned to the air inlet channel  22 . 
     As shown in  FIG. 2  and  FIG. 3 , the preload member  70  which includes at least one spring  71  is mounted in the spring chamber  34 . The spring  71  applies a preload to the relief valve  52 . The air flow in the exhaust chamber  33  will not flow into the spring chamber  34  because that the exhaust chamber  33  and the spring chamber  34  are separated from each other. The air flow in the return channel  35  also won&#39;t flow into the spring chamber  34 . Thus the spring  71  will not shake or shift due to the relief flow or the exhaust flow. Thereby the assembly position of the spring  71  in the spring chamber  34  remains and the same abutting force (the above preload) is applied to the relief valve  52  by the spring  71 . Therefore accurate actuation of the relief valve  52  is ensured and the stability of the mini air pump  100  during the blowing-up is improved. 
     In a nutshell, in the mini air pump  100 , the spring chamber  34  is not only disconnected from the exhaust chamber  33  but also the return channel  35  so as to prevent the exhaust flow or the return flow from flowing into the spring chamber  34 . Thus the spring  71  is relatively stably positioned in the spring chamber  34  to ensure that the abutting force applied to the relief valve  52  by the spring  71  remains the same and the relief valve  52  can actuate more accurately. Therefore the stability of the mini air pump  100  during the blow-up of the objects to be inflated is increased. 
     Furthermore, noise caused by air flow can be reduced due to the return flow being exhausted to the air inlet channel  22 , instead of being directly released to the atmosphere. And the operating noise of the mini air pump  100  is further minimized. 
     In some embodiments of the present invention, the air outlet valve  51  and the relief valve  52  are integrally formed on a valve membrane  50 , as shown in  FIG. 1  together with  FIG. 2  and  FIG. 3 . That means the air outlet valve  51  and the relief valve  52  are integrated with the valve membrane  50 . The valve membrane  50  is clipped between the valve seat  31  and the pump cover  32 . The air outlet valve  51  is used to control on/off of the exhaust channels  311  while the pressure of the air in the exhaust chamber  33  is regulated through the relief valve  52 . Thus the regulation of the blow-up of the objects to be inflated by the mini air pump  100  is achieved. 
     More specifically, the relief valve  52  is formed on one side of the valve membrane  50  facing the valve seat  31 . The valve seat  31  is provided with a groove  312  while the valve membrane  50  is provided with at least one communication hole  53  by which the groove  312  and the exhaust chamber  33  are communicating with each other. The air flow in the exhaust chamber  33  can flow to the groove  312  through the communication hole  53 . When the relief valve  52  is open, the air flow moves from the groove  312  to the return channel  35 . Thereby pressure relief is achieved. 
     As shown in  FIG. 1 , the groove  312  includes a circular groove  3121  and a plurality of long grooves  3122  which are arranged around and radiated from the circular groove  3121 . A free end of the long groove  3122  is arranged corresponding to the communication hole  53 . As shown in  FIG. 2  and  FIG. 3 , the return channel  35  is located at a central portion of the pump body  30  while the exhaust chamber  33  is located around the pump body  30 . The air flow in the exhaust chamber  33  is directed to the central circular groove  3121  through the long grooves  3122 . Then the air flow is output through the return channel  35  when the relief valve  52  is open. 
     As shown in  FIG. 2  and  FIG. 3 , the relief valve  52  is a circular flange which is arranged around an entrance of the return channel  35  and is directly abutting against the valve seat  31 . The spring  71  of the preload member  70  is abutting against the valve membrane  50  so that the circular flange is tightly attached to the valve seat  31 . When the air pressure in the exhaust chamber  33  is insufficient to push and open the relief valve  52 , the groove  312  and the return channel  35  are not communicating with each other. While the air pressure in the exhaust chamber  33  is larger than the abutting force of the spring  71 , the relief valve  52  is moved upward so that the circular flange and the attached surface of the valve seat  31  are separated from each other to allow the groove  312  and the return channel  35  communicating with each other. 
     In a preferred embodiment, as shown in  FIG. 1  and  FIG. 3 , a positioning rod  54  is mounted on the other side of the valve membrane  50 . The preload member  70  further includes a spring seat  72  and a stopper  73 . The positioning rod  54  is inserted through the spring seat  72  and one end of the spring  71  is abutting against and mounted in a limit slot  721  defined in the spring seat  72 . The spring seat  72  is positioned on the valve membrane  50  by the positioning rod  54 . The spring  71  is locked in the limit slot  721  and applying an abutting force to the spring seat  72  so that the relief valve  52  is further abutting against the valve seat  31 . That means the spring  71  and the valve membrane  50  are connected firmly by the spring seat  72  in combination with the positioning rod  54 . 
     In another preferred embodiment, refer to  FIG. 1  and  FIG. 3 , a guiding chamber  321  communicating with the spring chamber  34  is formed in the pump cover  32  and the other end of the spring  71  is extended into the guiding chamber  321  while the stopper  73  which applies a pre-tension to the other end of the spring  71  is mounted in the guiding chamber  321 . The two ends of the spring  71  is limited between the spring seat  72  and the stopper  73  while the cylindrical surface of the spring  71  is limited in the guiding chamber  321  for preventing shaking or weaving of the spring  71 . The stability of the preload member  70  within the spring chamber  34  is further improved. 
     As shown in  FIG. 1  and  FIG. 3 , in a preferred embodiment of the present invention, the bladder base  20  is further provided with a plurality of sink slots  23  each of which is communicating with the air inlet channel  22  and the return channel  35  correspondingly. By the sink slots  23 , the return flow is dispersed and delivered into different air inlet channels  22  to prevent the return flow from concentrating in and flowing out from the return channel  35  on the bladder base  20 . Thereby air flow noise is further reduced. 
     As shown in  FIG. 2  and  FIG. 3 , in a preferred embodiment of the present invention, a valve cap  80  is disposed over the pump cover  32  and a buffer chamber  81  is constructed by the pump cover  32  and the valve cap  80 . The buffer chamber  81  is communicating with the exhaust chamber  33 . That means the air flowing out from the exhaust chamber  33  is reaching the buffer chamber  81  first, not being directly delivered to the object to be inflated. Thereby the air flow is delivered to the outside after noise attenuation in the buffer chamber  81 . Therefore the operating noise of the mini air pump  100  is further reduced. 
     In order to avoid the air flow returning to the exhaust chamber  33 , a one-way valve  90  is arranged at an air vent of the valve cap  80  or the pump cover  32 . The one-way valve  90  is open when air in the exhaust chamber  33  is delivered to the outside. While the air in the exhaust chamber  33  is not delivered to the outside, the one-way valve  90  is closed. 
     In some other embodiments of the present invention, the air inlet valve  40  is integrally formed on the diaphragm  10  and arranged corresponding to an outlet of the air inlet channel  22 . That means the air inlet valve  40  is a part of the e diaphragm  10 . When the air is delivered into the bladder cavity  111 , the intake air flow first is directly passed through the air inlet channel  22  of the bladder base  20  to be sent into the bladder cavity  111 . 
     It should be understood that terms such as “top”, “bottom”, “in”, “out”, “upper”, “lower”, etc. should be constructed to refer to the orientation as then described or as shown in the drawings. These relative terms are for convenience of description and do not require that the present invention to constructed or operated in a particular orientation. 
     In the present invention, unless specified or limited otherwise, the terms “mounted”, “coupled”, “connected”, “fixed” and the like are used broadly and may be, for example, fixed connections, detachable connection, or integral connection; may also be mechanical or electrical connections; may also be direct connections or indirect connections via intervening structures; may also be inner communications or interaction of two elements, which can be understood by those skilled in the art according to specific situations. 
     In the present disclosure, unless specified or limited otherwise, the first feature “on” or “under” the second feature may include direct contact of the first and second features, and may also include the first and second features are not in direct contact but through additional features between them. Moreover, the first feature is “on”, “over” and “above” the second feature means the first feature directly is right on the top of or diagonally above the second feature, or merely indicating that the first feature is at a higher level than the second feature. The first feature is “beneath”, “under” and “below” the second feature means the first feature is directly is just beneath or diagonally below the second feature, or merely the first feature is at a lower level than the second feature. 
     In the description of the present specification, the description with reference to the term “one embodiment”, “some embodiments”, “an example”, “a specific example”, or “some examples” etc., means that particular features, structures, materials, or characteristics of the described embodiment is included in at least one embodiment or example of the present invention. In the present specification, the schematic description related to the above term is not necessary for the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be connected in at least one embodiment or example in a suitable manner. 
     The above description is only the preferred embodiments of the present invention, and is not intended to limit the present invention in any form. Although the invention has been disclosed as above in the preferred embodiments, they are not intended to limit the invention. A person skilled in the relevant art will recognize that equivalent embodiment modified and varied as equivalent changes disclosed above can be used without parting from the scope of the technical solution of the present invention. All the simple modification, equivalent changes and modifications of the above embodiments according to the material contents of the invention shall be within the scope of the technical solution of the present invention.