Patent application number | Description | Published |
20090100876 | METHOD OF MANUFACTURING OPTICAL FIBER BASE MATERIAL AND APPARATUS OF THE SAME - A method of manufacturing an optical fiber base material includes: forming a porous glass base material by depositing glass particles; providing a synthetic quartz glass vessel at least partly made of quartz glass which contains aluminum equal to or less than 0.01 ppm; introducing dehydration reaction gas and inert gas into the vessel; heating a portion made of quartz glass which contains aluminum equal to or less than 0.01 ppm in the vessel that contains the dehydration reaction gas and the inert gas; and inserting the porous glass base material into the heated vessel to dehydrate and sinter the porous glass base material. | 04-23-2009 |
20090211302 | METHOD OF MANUFACTURING OPTICAL FIBER BASE MATERIAL AND APPARATUS OF THE SAME - A method of manufacturing an optical fiber base material includes: forming a porous glass base material by depositing glass particles; providing a vessel which employs a composite tube, the composite tube including a portion formed by jacketing a first quartz glass containing aluminum equal to or less than 0.01 ppm with a second quartz glass containing aluminum equal to or more than 15 ppm; introducing dehydration reaction gas and inert gas into the vessel; heating the jacketed portion in the vessel which contains the dehydration reaction gas and the inert gas; and inserting the porous glass base material into the heated vessel to dehydrate and sinter the porous glass base material. | 08-27-2009 |
20100011813 | QUARTZ GLASS MANUFACTURING METHOD AND QUARTZ GLASS MANUFACTURING APPARATUS - Provided is a quartz glass manufacturing method that involves using one or more burners, supplying hydrogen and oxygen to the one or more burners to generate an oxyhydrogen flame, introducing a silicide into the oxyhydrogen flame, forming a porous base material by depositing silicon dioxide generated from a flame hydrolysis reaction with the silicide, and heating and sintering the porous base material to form transparent glass, the method comprising supplying hydrogen that is stored or made at a normal temperature to the one or more burners; controlling a hydrogen flow rate using a measurement apparatus or control apparatus that performs measurement based on heat capacity of a gas; vaporizing liquid hydrogen stored in a low-temperature storage chamber, and supplying the vaporized liquid hydrogen to the one or more burners as backup hydrogen; switching from the hydrogen to the backup hydrogen; and when switching, adjusting the hydrogen flow rate to a value obtained by multiplying the hydrogen flow rate immediately after switching by a predetermined correction coefficient. | 01-21-2010 |
20100015038 | HYDROGEN SUPPLY EQUIPMENT - Provided is hydrogen supply equipment that, when switching hydrogen supplied to equipment using hydrogen from (i) hydrogen produced at a normal temperature or hydrogen stored at a normal temperature to (ii) hydrogen stored at a low temperature, supplies the equipment using hydrogen with normal hydrogen obtained by returning the hydrogen at the low temperature to a normal temperature and then passing this hydrogen through equipment for accelerating a conversion from parahydrogen to orthohydrogen. | 01-21-2010 |
20100209859 | APPARATUS AND METHOD FOR SUPPLYING HYDROGEN GAS, AND QUARTZ GLASS MANUFACTURING APPARATUS - There is provided an apparatus for supplying a hydrogen gas to a quartz glass manufacturing apparatus including a burner that generates an oxyhydrogen flame when supplied with the hydrogen gas, where the apparatus includes: a first hydrogen supply system that supplies a hydrogen gas in which isotopes are in equilibrium; a second hydrogen supply system that supplies a hydrogen gas in which isotopes are out of equilibrium; a flow rate control section that includes: a valve that changes a flow rate of the hydrogen gas to be supplied to the burner; a first flow rate measuring section that measures the flow rate of the hydrogen gas to be supplied to the burner by measuring a heat capacity; and a control section that controls the valve in such a manner that a measured value obtained by the first flow rate measuring section approaches a set value input from outside; a second flow rate measuring section that measures the flow rate of the hydrogen gas to be supplied to the burner by measuring a different factor than the heat capacity; and a set value compensating section that compensates the set value by multiplying the set value by a ratio between the measured value obtained by the first flow rate measuring section and a measured value obtained by the second flow rate measuring section. | 08-19-2010 |
20110107797 | OPTICAL FIBER PREFORM MANUFACTURING METHOD AND OPTICAL FIBER PREFORM MANUFACTURING DEVICE - An optical fiber base material manufacturing method includes: supplying oxygen, hydrogen, and silicide to a core deposition burner; depositing silicon dioxide; adjusting a drawing up speed so that a deposition tip position remains at the same position in accordance with growth of a porous base material; calculating an average of the drawing up speed at each preset time interval; calculating a difference of the calculated average from a preset value of the drawing up speed; correcting a flow rate of silicon tetrachloride when the supplied hydrogen is hydrogen produced or stored at normal temperature, and correcting a flow rate of hydrogen when the supplied hydrogen is hydrogen obtained by vaporizing liquid hydrogen, where when correcting the flow rate of hydrogen, a flow rate of hydrogen supplied to a cladding deposition burner is also corrected in a ratio of before and after the correction of the flow rate of the hydrogen. | 05-12-2011 |
20130298611 | METHOD OF MANUFACTURING OPTICAL FIBER BASE MATERIAL AND APPARATUS OF THE SAME - A method of manufacturing an optical fiber base material includes: forming a porous glass base material by depositing glass particles; providing a synthetic quartz glass vessel at least partly made of quartz glass which contains aluminum equal to or less than 0.01 ppm; introducing dehydration reaction gas and inert gas into the vessel; heating a portion made of quartz glass which contains aluminum equal to or less than 0.01 ppm in the vessel that contains the dehydration reaction gas and the inert gas; and inserting the porous glass base material into the heated vessel to dehydrate and sinter the porous glass base material. | 11-14-2013 |
20140283557 | QUARTZ GLASS MANUFACTURING METHOD USING HYDROGEN OBTAINED BY VAPORIZING LIQUID HYDROGEN - Provided is a quartz glass manufacturing method that involves using one or more burners, supplying hydrogen and oxygen to the one or more burners to generate an oxyhydrogen flame, introducing a silicide into the oxyhydrogen flame, forming a porous base material by depositing silicon dioxide generated from a flame hydrolysis reaction with the silicide, and heating and sintering the porous base material to form transparent glass, the method comprising supplying hydrogen that is stored or made at a normal temperature to the one or more burners; controlling a hydrogen flow rate using a measurement apparatus or control apparatus that performs measurement based on heat capacity of a gas; vaporizing liquid hydrogen stored in a low-temperature storage chamber, and supplying the vaporized liquid hydrogen to the one or more burners as backup hydrogen; switching from the hydrogen to the backup hydrogen; and when switching, adjusting the hydrogen flow rate to a value obtained by multiplying the hydrogen flow rate immediately after switching by a predetermined correction coefficient. | 09-25-2014 |