| 摘要 |
1,261,748. Infra-red heating element. FUJI SHASHIN FILM K.K. 6 May, 1969 [18 May 1968], No. 23119/69. Heading H5H. To prevent a substantial area of the electrical heating strip '22 engaging the inside of heat resistant glass tube 21 on thermal expansion the strip 22 has at least one bent portion 23 intermediate its ends engaging the glass tube 21. Thus the bent portion or portions 23 absorb the thermal expansion and only the bent portion or portions of the strip engage the tube. 'The'bent portions may extend-on both sides of the ship as shown 'or on only one side 'thereof. The heat resistant tubes are made of quartz glass or crystalline glass. A plate heater was made from a plurality of glass tube heating elements of the type described above laid side by side with all the heating strips lying in the same plane, the glass tubes being cemented to transverse glass reinforcing tubes. The glass of the heating tubes consists of LiO 2 -Al 2 O 3 -SiO 2 with ZrO 2 added as a nucleii forming agent. An aluminium reflector plate was arranged on one side of the heating plate. The plate heater may be used in a surface heater or foot-warmer. |
