| 摘要 |
<PICT:0996423/C1/1> <PICT:0996423/C1/2> In a method of tempering glass sheets a hot sheet of glass is vertically suspended along its top edge solely by tongs and jets of fluid, preferably oil, are downwardly directed against opposite faces of the sheet, the gas passing from between the quench heads at the bottom edge of the glass. A sheet of glass 19 is suspended by tongs 20 from a track 21 between an opposed pair of quench heads 10, 11 shaped to open male and female pressing dies. The dies are operated by pneumatic rams 17, 18. The die surfaces are faced with a smooth material having a low coefficient of heat transfer, e.g. a smooth refractory gypsum cement or a material of 99% fused silica plus binder. The pressing surfaces of the dies have a multiplicity of downwardly pointing orifices 24, spaced in staggered rows and columns about 1 1/4 inches apart, through which air under pressure from the quench heads 10, 11 is directed on to the sheet faces. The orifices are downwardly inclined at an angle of not more than 45 degrees to the horizontal and preferably at 10 degrees thereto. The jets of air issuing therefrom impinge on the glass directly opposite another jet. The quench heads may be moved with an orbital or circular motion during tempering. The heads 10, 11 have adjustable stops 30, 31 to limit their movement during pressing. If it is not desired to temper the whole surface the orifices 24 may be omitted where tempering is not desired. |
