| 摘要 |
<p>Managing pressure within a thickness-control-zone (muffle door) housing (20) relative to pressures in a glass-making machine enclosure (60) and an upper chamber (40)—that is disposed outside the enclosure—so as to minimize or control undesired airflows that would adversely affect thickness (9) of glass ribbon (8). According to one pressure-management technique, the pressure at a location (25) in the housing (20) is managed so as to be less than the pressure at a location (65) that is within the enclosure (60) as well as both outside and adjacent to the housing. In the event of a leak, as by a crack or unintended opening in the housing, for example, this pressure difference reduces or prevents airflow toward the ribbon and, thereby, undesired thickness variation in the ribbon. According to a second pressure-management technique, the pressure at location (25) is managed so as to be greater than the pressure in the upper chamber.</p> |
