Air pump

Abstract

An air pump has a body, a piston rod and a handle. The piston rod is movably inserted into the body and has a rod body, a convex ring and a first engaging part. The convex ring is laterally protruded from the rod body and has a retaining surface. The first engaging part is longitudinally mounted on the convex ring. The handle is mounted on the rod body and has a fixation trough, a retaining ring and a second engaging part. The retaining ring abuts against the retaining surface of the convex ring for preventing a relative rotation between the handle and the piston rod. The second engaging part is longitudinally mounted on the inner surface of the fixation trough and is engaged with the first engaging part of the piston rod. Therefore, the air pump increases the stability between the piston rod and the handle.

What is claimed is: 
     
         1 . An air pump comprising:
 a body being hollow and having:
 an end surface; and 
 a nozzle mounted on the end surface; 
   a piston rod movably inserted into the body and having
 a rod body having:
 a top end; and 
 a bottom end opposite to the top end of the rod body and inserted into the body; 
 
 a piston mounted on the bottom end of the rod body; 
 a convex ring radially formed on and protruded from the rod body near the top end of the rod body, and having:
 an outer surface; 
 a bottom surface; 
 a retaining surface formed on the bottom surface of the convex ring of the piston rod; and 
 
 a first engaging part longitudinally mounted on the outer surface of the convex ring of the piston rod; and 
   a handle mounted on the top end of the rod body and having
 a connecting end connected to the top end of the rod body; 
 a face formed on the connecting end of the handle; 
 a fixation trough formed in the face of the handle and having an inner surface; 
 a retaining ring radially protruded from the inner surface of the fixation trough and abutted against the retaining surface of the convex ring; and 
 a second engaging part longitudinally mounted on the inner surface of the fixation trough and engaged with the first engaging part of the piston rod. 
   
     
     
         2 . The air pump as claimed in  claim 1 , wherein the first engaging part of the piston rod is a protruding rib, and the second engaging part of the handle is a groove whereby the protruding rib is fixedly insertable in the groove. 
     
     
         3 . The air pump as claimed in  claim 1 , wherein the first engaging part of the piston rod is a groove and the second engaging part of the handle is a protruding rib whereby the protruding rib is fixedly insertable in the groove. 
     
     
         4 . The air pump as claimed in  claim 1 , wherein the handle is a T-shaped handle and has a transverse part and a longitudinal part, and the face of the handle is formed on an end surface of the longitudinal part of the handle. 
     
     
         5 . The air pump as claimed in  claim 2 , wherein the handle is a T-shaped handle and has a transverse part and a longitudinal part, and the face of the handle is formed on an end surface of the longitudinal part of the handle. 
     
     
         6 . The air pump as claimed in  claim 3 , wherein the handle is a T-shaped handle and has a transverse part and a longitudinal part, and the face of the handle is formed on an end surface of the longitudinal part of the handle. 
     
     
         7 . The air pump as claimed in  claim 1 , wherein the handle is cylindrical and the face of the handle is formed on an end surface of the cylindrical handle. 
     
     
         8 . The air pump as claimed in  claim 2 , wherein the handle is cylindrical and the face of the handle is formed on an end surface of the cylindrical handle. 
     
     
         9 . The air pump as claimed in  claim 3 , wherein the handle is cylindrical and the face of the handle is formed on an end surface of the cylindrical handle. 
     
     
         10 . The air pump as claimed in  claim 7 , wherein the air pump has multiple slip-resistant ribs and the slip-resistant ribs are formed around and protruding from the handle. 
     
     
         11 . The air pump as claimed in  claim 8 , wherein the air pump has multiple slip-resistant ribs and the slip-resistant ribs are formed around and protruding from the handle. 
     
     
         12 . The air pump as claimed in  claim 9 , wherein the air pump has multiple slip-resistant ribs and the slip-resistant ribs are formed around and protruding from the handle.