Asahi Glass Company, Limited

Device Engineering Co., Ltd.

Torex Semiconductor Ltd.

Torex Device Co., Ltd.

Satoru Ohkawa

Takahiro Murakami

Nobuhiro Shinohara

Seiji Miyazaki

Osamu Sakamoto

Chikao Tanaka

Norimasa Hane

Takeshi Naka

Hitoshi Onoda

A glass-melting furnace, which suppresses the effect of exhaust gas on molten glass quality, a process for producing molten glass, and a process and apparatus for producing glass products. The glass-melting furnace containing: a raw glass material particle feed portion disposed downwardly at a furnace wall portion in an upper portion of the glass-melting furnace; a heating unit provided under the feed portion, which forms a gas phase portion for converting raw glass material particles into liquid glass particles; a flue inlet disposed on the upstream side of the gas phase portion in a flow direction of the molten glass liquid; a furnace-bottom portion, which accumulates the liquid glass particles that produce the molten glass liquid; and a discharge portion, which discharges the molten glass liquid.

Glass-melting furnace, process for producing molten glass, apparatus for producing glass products and process for producing glass products

The present invention provides a process for producing a molten glass which can produce a molten glass having a good quality, a glass-melting furnace, a process for producing glass products and an apparatus for producing glass products. While an oxygen combustion burneris rotated by a motor, glass raw material particles (not shown) are dropped into a high-temperature gas phase atmosphere produced by a flame F of the oxygen combustion burner, to be changed into liquid glass particles. By rotation of an outlet (nozzle) of the oxygen combustion burner, the falling position of the liquid glass particles, changes with time. Accordingly, generation of bubbles caused by continuous fall of the liquid glass particles in a particular position on a molten glass liquid surface is prevented. Accordingly, it is possible to produce a molten glass having a good quality with few bubbles.

Process for producing molten glass, glass-melting furnace, process for producing glass products and apparatus for producing glass products

Glass raw material particles are dropped from an oxygen combustion burner, and the glass raw material particles are heated by a flame F of an oxygen combustion burnerand a thermal plasma P, to melt the particles. Liquid glass particlesproduced by the melting fall downwardly in a melting tank, and fall on a surface of a molten glass liquid G in the melting tank. Then, an upper layer Gof the molten glass liquid G is heated by electrodesof a heating apparatusprovided in the melting tank. By this method, air and residual gas generated in the molten glass liquid G and the liquid glass particlesfallen onto the surface of the molten glass liquid G, become bubbles, surface and are smoothly discharged.

A DC/DC converter includes a main switching element and a subordinate switching element, and is arranged to supply power to load via a coil. The ON-time of a subordinate switching element in a succeeding cycle is controlled based on a period of time tdif from the time when the subordinate switching element is turned off until the time when voltage at the point of connection of the two switching elements reaches a predetermined threshold value.

DC/DC converter

A control circuit for a DC/DC converter which includes a main switching element, a sub switching element, and a reactor in order to convert a DC input voltage to a DC output voltage. The control circuit comprises a clock signal generator for generating a clock signal during a blank period in which both the main and sub switching elements are off; a comparator for comparing a reference voltage and a voltage at a connection point between the main and sub switching elements and for outputting a comparison signal indicating a relation of magnitude between the reference voltage and the voltage at the connection point; and an operation mode switching section for monitoring the comparison signal at a timing corresponding to the clock signal in order to detect a voltage state at the connection point, and controlling the sub switching element in accordance with the voltage state.

Growing community of inventors

Tokyo, Japan

Satoru Ohkawa