Steam generating device

Abstract

A steam generating device includes a body having a waterway defined longitudinally therein, and an inlet and an outlet are respectively connected to the body and communicate with the waterway. A heating tube is connected to the body and located close to the waterway. A pre-heat tube is connected to outside of the body and has a first end for introducing cold water into the pre-heat tube and a second end connected to the inlet. The cold water is pre-heated in the pre-heat tube before entering the waterway so that the water in the waterway is easily transferred into steam.

1 . A steam generating device comprising:
 a body having a waterway defined longitudinally therein, an inlet and an outlet respectively connected to the body and communicating with the waterway, a heating tube connected to the body and located close to the waterway, and   a pre-heat tube connected to the body and having a first end and a second end, the first end adapted to introduce cold water into the pre-heat tube and the second end connected to the inlet.   
     
     
         2 . The device as claimed in  claim 1 , wherein the pre-heat tube has a U-shaped tubular body which includes the first end and the second end, a connection tube includes a first connection end and a second connection end, the body has a recess defined in an outside thereof and the recess is located close to the heating tube, the pre-heat tube is received in the recess and the first connection end is connected to the inlet of the body and the second connection end is connected to the second end of the pre-heat tube. 
     
     
         3 . The device as claimed in  claim 1 , wherein the pre-heat tube has a spiral tubular body which spirally located around the body, the second end of the pre-heat tube is connected to the inlet and the first end of the pre-heat tube adapted to introduce cold water into the pre-heat tube.