| 摘要 |
1,139,727. Electric resistance heaters. AGAPLATFORADLING A.B. 7 March, 1967 [13 April, 1966], No. 10575/67. Heading H5H. An electric room heater comprises a longitudinally slotted tube 1, e.g. of annealed steel, on to which fins 3 have been pushed and which surrounds a tubular resistor body 4. Before body 4 is inserted, a mandrel is drawn through tube 1 to radially expand it into tight contact with the fins. The slot (7, Fig. 4) may comprise overlapped tube edges, which overlap is removed by the expansion. Two tubes (8, Fig. 5) may be provided with the same fins (9), and their resistor bodies can be switched on independently. |
