Patent Publication Number: US-2007120027-A1

Title: Suction cup

Description:
BACKGROUND OF THE INVENTION  
      1. Field of Invention  
      The present invention relates generally to suction devices and more particularly to a suction cup with improved characteristics (e.g., increased sucking force).  
      2. Description of Related Art  
      There have been numerous suggestions in prior patents for suction cups. For example, one of the typical suction cup discloses a suction cup characterized in that a seat is put on the bell, a rubber ring is provided on the seat, a plurality of ribs are extended outward from the ring, and a pressing member is provided under the ribs such that pressing the bell will cause the pressing member to press the suction cup for securely adhering to the surface. Another typical suction cup discloses a suction cup characterized in that a fastening member is provided around the bell, and a threaded member is adapted to drive the bell upward a surface to create a vacuum therebetween so as to adhere to the surface with the additional help of lockingly engaging annular studs of the fastening member with grooves of a plate. The other typical one of suction cup discloses a suction cup characterized in that pressing a plate onto a surface and rotatably drive a cover to press same onto a periphery of the plate so as to create a vacuum that forces the plate to adhere to the surface.  
      Such prior sucking mechanisms are typically able to create a small sucking force. Hence, only a lightweight object can be supported by the suction cup. Further, their are relatively complex in constructions, trouble-prone, and unreliable in use. Thus, the need for improvement still exists.  
     SUMMARY OF THE INVENTION  
      It is therefore an object of the present invention to provide a suction cup comprising a resilient plate including a concave bottom and a projecting post having outer threads; a bell including a receptacle on an upper end thereof, a support pivotably secured in the receptacle, a bell body on a lower end thereof, an internal space open to both lateral sides of the bell body, a nut provided in the space, and an internal opening in communication with the space wherein the projecting post passes the opening to threadedly engage with the nut; and a pressing member put on a central portion of the plate around the middle part, the pressing member being disposed inside a bottom of the bell and being in contact with an inner bottom surface of the bell body, the pressing member including an annular member  31  and a plurality of pressing elements formed on a bottom of the annular member  31  whereby placing the suction cup onto a surface and continuously turning the nut will draw both the plate and the bell toward the surface and draw the pressing member onto the plate until a cavity defined by the plate and the surface is decreased to about zero for creating a vacuum to adhere the plate to the surface. By utilizing this suction cup, an increased sucking force is created.  
      In an aspect of the present invention the pressing elements are shaped as either ribs or teeth.  
      In another aspect of the present invention the pressing elements are either arcuate or straight.  
      The above and other objects, features and advantages of the present invention will become apparent from the following detailed description taken with the accompanying drawings.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a perspective view of a preferred embodiment of suction cup according to the invention;  
       FIG. 2  is an exploded view of the suction cup;  
       FIG. 3  is a cross-sectional view of the suction cup in its inoperative state;  
       FIG. 4  is a cross-sectional view of the suction cup in its operating state;  
       FIG. 5  is a detailed view of the area in circle of  FIG. 3 ;  
       FIG. 6  is a detailed view of the area in circle of  FIG. 4 ;  
       FIG. 7  is a bottom view of the suction cup with the plate removed;  
       FIG. 8  is a bottom view of the suction cup of another embodiment of the present invention with the plate removed; and  
       FIG. 9  is an environmental view of the suction cup with a device cradle mounted onto a support thereof. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      Referring to  FIGS. 1 and 2 , a suction cup in accordance with a preferred embodiment of the invention comprises a resilient circular plate  1  formed of soft plastics or rubber, having a slight concave configuration and including a middle projecting post  11  having outer threads  110 , a central concave portion  10  on a bottom of the projecting post  11 , an annular flat portion  12  on an outer circumferential portion of the concave portion  10 , and a tab on an outer portion of the annual flat portion  12 ; a bell  2  including a main body  21 , a spherical receptacle  26  on an upper end of the body  21 , a bell member  22  on a lower portion of the body  21 , an annular downward flange  220  on a circumference of the bell member  22 , an internal space  23  open to both lateral sides of the body  21 , a nut  24  provided in the space  23 , and an opening  25  disposed on the top of the bell member  22  in communication with the space  23  wherein the projecting post  11  passes the opening  25  to threadedly engage with the nut  24 ; and an annular pressing member  3  put on the annular flat portion  12  of the resilient circular plate  1  and being disposed inside a concave bottom of the bell body  21  or an inner bottom surface of the bell member  22  and being in contact with an inner surface of the bell member  22 , the pressing member  3  including an annular member  31  and a plurality of pressing elements in the form of arcuate ribs, or arcuate teeth  32 , or the like formed on a bottom of the annular member  31 , as shown in  FIG. 7 . Note that the pressing elements in another embodiment of the present invention may be shaped in the form of straight ribs, teeth  32 A, or the like formed on a bottom of the annular member  31 A, as shown in  FIG. 8 . In order to facilitate the suction cup to have immovably retained on the surface  4 , the diameter of the plate ( 1 ) is intentionally designed to be smaller than that of the bell member  22  of the bell ( 2 ), and the bottom of the flange  220  is higher than that of the plate ( 1 ), as shown in  FIGS. 3 and 4 .  
      Referring to FIGS.  3  to  8 , a sucking operation of the invention will be described in detailed below. Place the suction cup onto a flat surface  4 , as shown in  FIG. 3 . Next, continuously turn the nut  24  with one hand to draw both the projecting post  11  and a bell member  22  (i.e., the bell  2 ) toward the surface  4  and draw the pressing member  3  toward the annular flat portion  12  of the resilient circular plate  1  until a cavity  10 A defined by the concave portion  10  of the plate  1  and the surface  4  is decreased to about zero (as shown in  FIG. 4 ) in order to create a vacuum for causing the resilient circular plate  1  (i.e., the suction cup) to adhere to the surface  4 . Note that the sucking force is greatly enhanced since the pressing elements  32 · 32 A having been greatly increased its actuated area are urged against a whole top of the plate  1  by excessively tightening the nut  24 . As a result, the suction cup is immovably and captively retained on the surface  4  by the created vacuum as shown particularly in  FIGS. 4-8 . The above immovably retained state of suction cup on the surface  4  will be changed if the tab  13  is pulled up by hand.  
      Referring to  FIG. 9 , an application of the invention will be described in detailed below. The suction cup is mounted on a place (e.g., instrument board of an automobile). A device (e.g., mobile phone, PDA (Personal Digital Assistant), or the like) may be secured to a cradle  5  which is in turn mounted on a support  6  having a leg pivotably provided in the receptacle  26 .  
      While the invention herein disclosed has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims.