| 摘要 |
PURPOSE:Not to take time for a worker to manufacture a coaxial tube by brazing a second square copper pipe on the market to the side face of a first square copper pipe on the market while inserting a third square copper pipe on the market in the first square copper pipe, and then inserting insulators between the first and third pipes. CONSTITUTION:A square copper pipe 2 on the market(a second square copper pipe on the market) smaller in size (diameter) and longer than a square copper pipe 1 on the market(a first square copper pipe on the market) is brazed (4) and fixed to one side-face of the pipe 1 all over the length of the pipe 1 except both end-parts of the pipe 2. Then a square copper pipe 3 on the market(a third square copper pipe on the market) having the same length and same size as the pipe 2 has is inserted in the pipe 1 except both end-parts of the pipe 3. Then four long-sized insulating plates 11 of the same oblong shape in cross section are inserted in a space between the pipes 1 and 3 all over the length of the pipe 1. Thus a coaxial tube for supplying electricity to a high-frequency heating coil can be manufactured of only materials on the market and by a simple method, so that the manufacturing cost of the tube may be reduced while time for a worker to manufacture the tube may be reduced. |
