Patent Abstract:
A supplemental air pressure providing device adapted for use with an inflatable object includes an oscillator responsible for generating magnetic field and vibrating a casing, an air compressing device responsible for compressing air and noise silencer mounted inside the air compressing device for reducing noise generated while compressed air flows through the air compressing device for inflating the inflatable object.

Full Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a supplemental air pressure providing device, and more particularly, to an air pressure providing device for an inflatable object such that when air pressure of the inflatable object is below a predetermined level, the air pressure providing device is able to provide supplemental air pressure to the inflatable object to maintain the air pressure of the object. 
     2. Description of the Prior Art 
     Inflatable objects have been extensively used in all kinds of applications, e.g. in hospitals for patients, outdoors for recreations and indoors for comfort. No matter what application and in what site the inflatable object is used, one thing in common for all users is that all the inflatable objects leak eventually, which causes uncomfortable for the users. To avoid such a situation, the user will have to constantly check the air pressure of the inflatable objects to make sure the inflatable objects provide the required comfort. 
     While there is a leak in the inflatable object, the user turns on the air pump to increase the air pressure inside the inflatable object and when the air pressure reaches the required level, the user turns off the air pump. This routine may be readily done during the daytime for the illumination is enough to do whatever is necessary. However, during the nighttime, especially when the user is asleep, not only the illumination is seriously insufficient, the user&#39;s willingness to undergo a troubleshooting process for the leak is also extremely low. 
     To avoid the inconvenience caused by the leak of the inflatable object, the best policy is that the air pressure of the inflatable object is maintained the entire time when the inflatable object is in use. And to maintain the air pressure of the inflatable object, the best option is to use another air pump to provide additional air pressure to the inflatable object in time when the air pressure of the inflatable object is decreasing. However, the operation of the air pump normally generates a great deal of noise and the vibration thereof causes uncomfortable to the user lying on top of the inflatable object. 
     As a result of the above, it is an objective of the present invention to provide a supplemental air pressure providing device to not only inflate the inflatable object, but also have features to minimize un-comfort caused by the noise and vibration by the operation of the device. 
     SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a supplemental air pressure providing device to provide supplemental air pressure to an inflatable object when the air pressure of the inflatable object is not within a reasonable level. 
     Another objective of the present invention is to provide a supplemental air pressure providing device which is able to minimize the noise caused by its operation. 
     In order to accomplish the aforementioned objectives, the supplemental air pressure providing device of the present invention includes an outer housing, an inner housing, a cushion securely mounted between the inner housing and the outer housing to reduce the vibration between the outer housing and the inner housing, an oscillator selectively activated, a bellow engaged with and moved by the oscillator to generate compressed air into a chamber where noise silencer is mounted to absorb noise caused by air flow through the chamber and check valves mounted inside the chamber to prevent reverse air flow. 
     Another objective of the present invention is that the noise silencer is a cotton silencer which is able to absorb air flow noise so as to reduce the noise caused by the device of the present invention. 
     These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view showing the structure of the supplemental air pressure providing device of the present invention; 
         FIG. 2  is a cross sectional view of the chamber of the present invention; 
         FIG. 3  is a perspective view showing the chamber of the present invention; 
         FIG. 4  is a schematic view showing the noise silence room of the present invention; 
         FIG. 5  is a top view showing the supplemental air pressure providing device of the present invention; 
         FIG. 6  is a cross sectional view taken from line A-A of  FIG. 5 ; 
         FIG. 7  is a schematic view showing the internal structure of the chamber of the present invention; 
         FIG. 8  is a schematic view showing the operation of the chamber of the present invention; and 
         FIG. 9  is a schematic view showing another operation state of the chamber of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     With reference to  FIGS. 1˜6 , a supplemental air pressure providing device constructed in accordance with the present invention is adapted for use with an inflatable object  25  and includes an outer housing  23  having a first inlet  1  for ambient air to flow into the outer housing  23 , an inner housing  3  with a second inlet  2 ′, a first nozzle  21 , and a chamber  26 . 
     With reference to not only the above mentioned drawings, illustration from  FIG. 7  is also incorporated. It is learned that the chamber  26  is composed of a casing  5  with a third inlet  4  and an outlet  9 . An oscillator  22  is mounted next to the chamber  26  and a bellow device  30  is provided inside the chamber  26 . The oscillator  22  is able to generate magnetic field, which in turn will oscillate magnets  32  mounted on a metal casing  27 . The oscillation of the magnet  32  consequently drives the bellow device  30  to move. The bellow device  30  is composed of the metal casing  27  and a rubber cap  28  which is securely engaged with the metal casing  27 . Due to the engagement relationship between the metal casing  27  and the rubber cap  28 , the oscillation from the oscillator  22  will then drive the rubber cap  28  to move linearly. Inside the rubber cap  28 , at least one check valve, two in this embodiment, namely a first check valve  6  and a second check valve  7  respectively, is mounted to regulate air flow direction. Additionally, a cotton silencer  8  is mounted inside the chamber  26  to reduce noise caused by air flow. 
     With reference to  FIGS. 8 and 9 , it is noted that when the oscillator  22  is activated to generate magnetic field, the magnetic field will drive the magnets  32  on one end of the metal casing  27  to oscillate and consequently the metal casing  27  is moved accordingly. Air flows from the first check valve  6  and enters a space  31  inside the rubber cap  28  where the air is compressed due to the movement of the metal casing  27 . Then the air flows to the second check valve  7  from the space  31 . Additionally, the air flows through the cotton silencer  8 , the outlet  9  and out of the chamber  26 . 
     As shown in  FIG. 4 , a noise silencing room  11  is defined inside the inner housing  3  and has an inlet  10  and a second nozzle  19  defined in an outer periphery of the noise silencing room  11 . An air duct  20  is provided between the second nozzle  19  and the first nozzle  21 . Besides, a valve  12  and noise absorbent  17 ,  18 , made by such as cotton, are also provided inside the noise silencing room  11 . The valve  12  is provided with an inlet  13  and a unidirectional cap  14  mounted outside the valve  12  and having an outlet  15 . Furthermore, cotton silencers  2  may also be provided in the second inlet  2 ′ and/or the first nozzle  21 . 
     A cushion  24  made by such as rubber is provided between the noise silencing room  11  of the inner housing  3  and the outer housing  23  to greatly reduce noise caused by vibration. 
     From the structure and arrangement of all the components set forth above, it is noted that air flows from the first inlet  1  of the outer housing  23  and passes through the second inlet  2 ′, the cotton silencers  2  and reaches inner housing  3 . Then the air continues to flow through the third inlet  4  and enters the casing  5 . Before the air is compressed in the space  31 , the air passes the first check valve  6 . Then the air flows out from the second check valve  7  while passing through the cotton silencer  8  and the outlet  9 . Again, the air flows into the noise silencing room  11  from the inlet  10  and passes through the valve  12  from the inlet  13 . From the structure of the valve  12  as well as the noise silencing room  11 , gap is generated when the air is flowing upward to allow the air to flow therethrough. However, if the air is flowing downward, due to the strength of the air flow is not able to push away the valve  12 , there is no gap generated such that the air is prevented from flowing reversely. 
     From the valve  12 , the air flows into the unidirectional cap  14  and from the outlet  15 , a space  16 , the air reaches the noise absorbent  17 ,  18  to reduce the noise so generated. And from the second nozzle  19 , the air flows out of the noise silencing room  11  and from the air duct  20 , the air flows to the inflatable object from the first nozzle  21 . 
     It is to be noted that although the preferred embodiment of the present invention has been described, other modifications, alterations or minor change to the structure should still be within the scope defined in the claims. As those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention.

Technology Classification (CPC): 5