Air compressor having improved valve device

Abstract

An air compressor includes a cylinder housing, a piston moved to slide in the cylinder housing in a reciprocating action to generate pressurized air, and a sealing ring engaged into the piston and having an outer peripheral channel formed in an upper portion to form an outer peripheral rib, the outer peripheral rib of the sealing ring is extended out of the piston for slidably engaging with the inner peripheral surface of the cylinder housing and for making an air tight seal between the cylinder housing and the piston even when the piston is tilted relative to the cylinder housing. The sealing ring is retained between a base member and an upper cover member of the piston.

1 . An air compressor comprising: 
 a cylinder housing including a chamber formed therein, and defined by an inner peripheral surface,    a piston slidably received in said chamber of said cylinder housing and having a piston rod extended therefrom,    means for moving said piston relative to said cylinder housing in a reciprocating action in order to generate pressurized air, and    a sealing ring engaged into said piston and including an outer peripheral channel formed in an upper portion thereof, to form an outer peripheral rib, said outer peripheral rib of said sealing ring being extended out of said piston for slidably engaging with said inner peripheral surface of said cylinder housing and for making an air tight seal between said cylinder housing and said piston even when said piston is tilted relative to said cylinder housing.    
   
   
       2 . The air compressor as claimed in  claim 1 , wherein said piston includes a base member and an upper cover member engaged onto and located above said base member for retaining said sealing ring between said base member and said upper cover member of said piston.  
   
   
       3 . The air compressor as claimed in  claim 2 , wherein said upper cover member of said piston includes a peripheral flap extended toward said base member and engaged with said sealing ring for stably retaining said sealing ring in said piston.  
   
   
       4 . The air compressor as claimed in  claim 3 , wherein said sealing ring includes an inner peripheral channel formed therein for receiving said peripheral flap of said upper cover member and for solidly anchoring said sealing ring to said piston.  
   
   
       5 . The air compressor as claimed in  claim 2 , wherein said base member of said piston includes a peripheral wall extended upwardly therefrom to form an outer peripheral shoulder and an inner compartment therein, said upper cover member of said piston includes a swelling extended downwardly therefrom to engage into said inner compartment of said base member and to anchor said upper cover member to said base member.  
   
   
       6 . The air compressor as claimed in  claim 1 , wherein said outer peripheral rib of said sealing ring includes an inclined surface for engaging with said inner peripheral surface of said cylinder housing.  
   
   
       7 . The air compressor as claimed in  claim 6 , wherein said outer peripheral rib of said sealing ring includes an upper flat surface formed in an upper portion thereof and formed beside said inclined surface thereof.  
   
   
       8 . The air compressor as claimed in  claim 1 , wherein said piston includes an air passage formed therein for air flowing purposes, and includes a valve device attached to said piston for selectively blocking said air passage of said piston when said piston is moved relative to said cylinder housing in a compressing stroke, and for opening said air passage of said piston when said piston is moved relative to said cylinder housing in a returning stroke.  
   
   
       9 . The air compressor as claimed in  claim 8 , wherein said valve device includes a first side secured to said piston and including a second side opposite to said first side thereof, and said piston includes means for limiting said second side of said valve device to move relative to said piston and to prevent said second side of said valve device from being over bent relative to said first side of said valve device.  
   
   
       10 . The air compressor as claimed in  claim 9 , wherein said limiting means includes an ear extended therefrom and located above said second side of said valve device for engaging with said second side of said valve device and for limiting said second side of said valve device to bend or move relative to said piston.  
   
   
       11 . The air compressor as claimed in  claim 10 , wherein said valve device includes an opening form in said second side thereof, and said limiting means includes a limiting device extended from said piston and extended through said opening of said valve device, and having said ear extended from said limiting device.  
   
   
       12 . The air compressor as claimed in  claim 8 , wherein said valve device includes an inner peripheral slot formed therein to form a first blade member and a second blade member and to have said inner peripheral slot located between said first blade member and said second blade member.  
   
   
       13 . The air compressor as claimed in  claim 12 , wherein said valve device includes at least one coupling member provided in said second side thereof and coupled between said first blade member and said second blade member, for coupling said first blade member and said second blade member together.  
   
   
       14 . The air compressor as claimed in  claim 8 , wherein said piston includes a bar extended upwardly therefrom for engaging with said valve device and for positioning and for anchoring said valve device.  
   
   
       15 . The air compressor as claimed in  claim 1  further comprising a supporting plate to support said cylinder housing, said cylinder housing including an outlet tube having a compartment formed therein and communicating with said chamber of said cylinder housing for receiving pressurized air from said chamber of said cylinder housing, and including a valve seat provided in said outlet tube and located between said outlet tube and said cylinder housing, and a spring-biased check valve disposed in said outlet tube and engaged with said valve seat, to prevent the pressurized air from flowing backwardly from said compartment of said outlet tube into said chamber of said cylinder housing.  
   
   
       16 . The air compressor as claimed in  claim 15 , wherein said moving means includes a motor attached to said plate and having a spindle extended through said plate, and an eccentric member coupled to said spindle and having a pin coupled to said piston rod, to move said piston relative to said cylinder housing.  
   
   
       17 . The air compressor as claimed in  claim 16 , wherein said plate includes a gear rotatably attached thereto and having a space formed by a peripheral casing to receive said eccentric member.  
   
   
       18 . The air compressor as claimed in  claim 1 , wherein said cylinder housing includes a first duct, a second duct, and at least one third duct extended outwardly from said outlet tube and communicating with said compartment of said outlet tube, for receiving the pressurized air from said outlet tube, a pressure gauge attached to said first duct, a nozzle coupled to said second duct.