Patent Publication Number: US-2011068197-A1

Title: Air blower

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a cleaning device, in particular to an air blower for cleaning dust. 
     2. Description of Prior Art 
     An air blower is often used to blow away the dust in a camera, on a surface of a precise instrument or a lens, or in gaps of a keyboard. 
     A conventional air blower includes an elastic ball body for receiving air, a nozzle and a check valve. The nozzle and the check valve are provided on two open holes of the elastic ball body respectively. When the elastic ball body is rapidly pressed by a user, the check valve blocks one of the two open holes, so that the airflow can be only allowed to pass through the other open hole to blow away the dust. 
     Such an air blower has to be rapidly pressed by the user to generate airflow of sufficient pressure. Thus, the hand of the user may feel ache after pressing the elastic ball body for a period of time. On the other hand, the speed of pressing the elastic ball body is limited, so that it is impossible to generate a pressurized airflow strong enough to blow away the dust completely. Furthermore, when the force of pressing the elastic ball body is released, the pressure of external air is larger than that within the elastic ball body, so that the check valve is opened by the external air and thus the external air enters the elastic ball body again. However, the nozzle is not provided with any means for preventing against the entrance of external air. Thus, a portion of external air enters the elastic ball body through the nozzle. As a result, the dust just blown away may be sucked into the elastic ball body to jam the nozzle. Further, the dust sucked in the nozzle may be blown out of the nozzle in the subsequent use to fall on the camera, the precise instrument, the lens or the keyboard. 
     SUMMARY OF THE INVENTION 
     In view of the above, it is necessary to provide an air blower capable of preventing against the entrance of external airflow through a nozzle thereof. 
     The present invention discloses an air blower including an elastic ball body provided with a nozzle hole and a check hole, a nozzle disposed in the nozzle hole, and a check valve disposed in the check hole. A check portion of the nozzle is disposed into the elastic ball body and is tightly connected with the edge of the nozzle hole. The check portion is provided therein with a stopping assembly for blocking or opening the nozzle hole. 
     With the stopping assembly provided at the nozzle hole, the nozzle hole is opened when the airflow within the elastic ball body is ejected out and closed when the external air enters the elastic ball body. In this way, the external air can be prevented from entering the air blower through the nozzle efficiently. 
     Preferably, the stopping assembly includes a sealing pad, a magnetic ring and a gasket. The gasket is made of iron or steel. The magnetic ring is sheathed outside the sealing pad and tightly connected with the gasket. 
     Preferably, an inner wall of the check portion is provided with ribs protruding toward a post-like space enclosed by the check portion. The sealing pad and the magnetic ring are disposed in the post-like space and positioned by the ribs in the middle of the post-like space. The sealing pad is in interference fit with the inner wall of the check portion to be fixed at an opening of the nozzle in communication with the elastic ball body. 
     Preferably, the number of the ribs is at least three. 
     Preferably, the sealing pad includes a sealing surface, a hook and a cylinder connected between the sealing surface and the hook. The magnetic ring is sheathed on the cylinder and fixed between the sealing surface and the hook. The hook abuts against the edge of an inner hole of the gasket. 
     Preferably, the rib is provided with a stepped portion for stopping the sealing surface. A distance is formed between the sealing surface and the stepped portion when the magnetic ring is connected with the gasket. 
     With the connection or disconnection between the sealing pad and the gasket, the nozzle hole can be opened or closed. Further, by overcoming the connecting force generated between the magnetic ring and the gasket, a stronger airflow can be generated. 
     Preferably, a periphery of the nozzle is provided with an annular slot. The nozzle hole is in interference fit with the annular slot. 
     Preferably, the check valve includes a valve body. The periphery of the valve body is in interference fit with the edge of the check hole, so that the connecting portion between the valve body and the check hole is kept airtight. 
     Preferably, the check valve further includes a check piece. The valve body is provided with an upper stepped portion and a lower stepped portion. The check piece is located between the upper stepped portion and the lower stepped portion. 
     Preferably, the check valve includes a valve body and a check piece integrally formed together. The interior of the valve body is formed into a hollow channel. The check piece is made of an elastic material. The check piece covers one end of the channel and is elastically connected with the valve body through an elastic connecting portion thereof. 
    
    
     
       BRIEF DESCRIPTION OF DRAWING 
         FIG. 1  is an exploded perspective view showing an air blower according to a first embodiment of the present invention; 
         FIG. 2  is a cross-sectional view showing the air blower according to the first embodiment of the present invention; 
         FIG. 3  is a schematic view showing a check valve according to a second embodiment of the present invention; 
         FIG. 4  is a top view showing the check valve according to the second embodiment of the present invention; 
         FIG. 5  is a cross-sectional view of the check valve along the line A-A in  FIG. 4 ; and 
         FIG. 6  is an exploded perspective view showing the structure of a nozzle from another viewing angle. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The detailed description and technical contents of the present invention will be explained with reference to the accompanying drawings. However, it should be understood that the drawings are illustrative only, but not used to limit the present invention. 
     Please refer to  FIG. 1 , which is an exploded perspective view showing an air blower of the present invention. The air blower includes an elastic ball body  100  provided with a nozzle hole  110  and a check hole  120  (as shown in  FIG. 2 ), a nozzle  200  provided in the nozzle hole  110 , and a check valve  300  provided in the check hole  120 . A check portion  210  of the nozzle  200  is disposed into the elastic ball body  100  and tightly connected with the edge of the nozzle hole  110 . The interior of the check portion  210  is provided with a stopping assembly  400  for blocking or opening the nozzle hole  110 . 
     The elastic ball body  100  generally has an elastic plastic casing. The nozzle hole  110  and the check hole  120  are provided on two opposite ends of the elastic ball body  100 . 
     The nozzle  200  is provided with an annular slot  220 . The check portion  210  is disposed into the elastic ball body  100  through the nozzle hole  110  in such a manner that the annular slot  220  is in interference fit with the nozzle hole  110 . In this way, the connecting portion between the nozzle  200  and the elastic ball body  100  is airtight. The inner wall of the check portion  210  is provided with ribs  212  as shown in  FIG. 6 . The ribs  212  protrude toward a post-like space enclosed by the check portion  210 . Preferably, the number of the ribs  212  is at least three. Further, each of the ribs  212  is provided with a stepped portion  211 . 
     The check valve  300  includes a valve body  310  and a check piece  320 . The periphery of the valve body  310  is in interference fit with the edge of the check hole  120 , so that the connecting portion there between is airtight. The interior of the valve body  310  is provided with stopping ribs  313 . Preferably, the number of the stopping ribs  313  is at least three. The check piece  320  is located in the stopping ribs  313  and movable between an upper stepped portion  311  and a lower stepped portion  312  (as shown in  FIG. 2 ). 
     The stopping assembly  400  includes a sealing pad  410 , a magnetic ring  420  and a gasket  430 . The gasket  430  is made of iron or steel. The magnetic ring  420  is sheathed outside the sealing pad  410  and is tightly connected with the gasket  430 . 
     The sealing pad  410  includes a sealing surface  411 , a hook  412  and a cylinder  413  connected between the sealing surface  411  and the hook  412 . The magnetic ring  420  is sheathed on the cylinder  413  and fixed between the sealing surface  411  and the hook  412 . The hook  412  abuts against the edge of an inner hole  431  of the gasket  430 . 
     The sealing pad  410  and the magnetic ring  420  are disposed in the post-like space enclosed by the check portion  210  and located in the middle of the post-like space by the ribs  212 . The stepped portion  211  of the rib  212  is configured to the stop the sealing surface  411 . When the magnetic ring  420  is tightly connected with the gasket  430 , the sealing surface  411  is separated from the stepped portion  211  by a predetermined distance. The gasket  439  is in interference fit with the inner wall of the check portion  210  and fixed at an opening of the nozzle  200  in communication with the elastic ball body  100 . 
     Next, the operation of the air blower of the present embodiment will be described. 
     When an external force is exerted on the elastic ball body  100 , since the space within the elastic ball body  100  is compressed, the internal pressure of the elastic ball body  100  is increased. When the internal pressure of the elastic ball body  100  is increased continuously to such an extent that the force exerted on the sealing surface  411  exceeds the connecting force between the magnetic ring  420  and the gasket  430 , the sealing pad  410  together with the magnetic ring  420  are forced to be separated from each other. At this time, the sealing surface  411  is stopped by the stepped portions  211 , so that the airflow can flow through the gaps between the ribs  212  and then flow to the outside of the nozzle  200 . When the elastic ball body  100  is pressed, since the internal pressure of the elastic ball body  100  is larger than the external pressure, the check piece  320  of the check valve  300  is pressed by the internal airflow to the lower stepped portion  312 , thereby sealing the check hole  120  and preventing the air from leaking through the check hole  120 . The airflow generated by the air blower of the present embodiment is stronger than that generated by a conventional air blower, so that a better cleaning effect can be achieved by the present invention. 
     After the external force for pressing the elastic ball body  100  is released, the casing of the elastic ball body  100  returns to its original shape by means of its elastic restoring force. At this time, since the internal space is increased, the air within the elastic ball body  100  is diluted and the internal pressure is decreased. Thus, the external air pushes the sealing pad  410  and the check piece  320  toward the interior of the elastic ball body  100 . With the magnetic attracting force between the magnetic ring  420  and the gasket  430 , the sealing pad  410  and the gasket  430  can be tightly connected to each other again after the internal pressure of the elastic ball body  100  is decreased to a predetermined level, thereby closing the nozzle hole  110  without waiting for the release of the external force. Thus, the entrance of external air into the elastic ball body  100  can be prevented effectively. 
     In the previous embodiment, the check valve  300  is configured to have a separated check piece  310  and the valve body  320 . As shown in  FIG. 3 , the check valve  300  includes a valve body  340  and a check piece  330  integrally formed with each other. The interior of the valve body  34  is a hollow channel as shown in  FIG. 5 . The check piece  330  is made of an elastic material. The check piece  330  covers one end of the channel and is elastically connected to the valve body  340  by means of a connecting portion  350  thereof. 
     As shown in  FIG. 4 , it is a top view showing the check valve  300  of the present embodiment. The diameter of the check piece  330  is slightly larger than that of the channel inside the valve body  340 . One end of the valve body  340  covers the channel and is connected to the valve body  340  through the connecting portion  350 . 
     As shown in  FIG. 5 , it is a cross-sectional view of the check valve  300  along the line A-A in  FIG. 4 . Since the check piece  330  and the connecting portion  350  are made of elastic materials, the channel inside the valve body  340  can be opened or closed easily. When the elastic ball body  100  is pressed, the internal pressure of the elastic ball body  100  is larger than the external pressure. Since the diameter of the check piece  330  is larger, the check piece  330  is pushed to block the channel. When the elastic ball body  100  returns to its original shape and the internal pressure is decreased, the check piece  330  is pushed from the outside to open the channel. In this way, the airflow can enter the elastic ball body  100  through the channel. 
     Although the present invention has been described with reference to the foregoing preferred embodiments, it will be understood that the invention is not limited to the details thereof. 
     Various equivalent variations and modifications can still occur to those skilled in this art in view of the teachings of the present invention. Thus, all such variations and equivalent modifications are also embraced within the scope of the invention as defined in the appended claims.