Patent DE-102011001329-B3 (DE)
Title: Controlling peripheral speed of transport rollers of glass tube manufacturing plant, comprises providing transport rollers for removing hot glass tube strand, and assigning transport roller of contactless measuring speed sensor
Inventor: HUMMER ALEXANDER
IPC: C03B17/04
Filed: 2011-03-16
Granted: 2012-03-08
Abstract: The method comprises: providing the transport rollers for removing hot glass tube strand (2), which is associated with drive units for driving the respective associated transport roller or the transport roller and has a deduction device downstream present in deduction direction of the glass tube strand for removing the glass tube strand with a predetermined speed; and assigning the transport roller of a contactless measuring speed sensor that measures an actual deduction speed of the glass tube strand in an area of the respective associated transport roller. The method comprises: providing the transport rollers for removing hot glass tube strand (2), which is associated with drive units for driving the respective associated transport roller or the transport roller and has a deduction device downstream present in deduction direction of the glass tube strand for removing the glass tube strand with a predetermined speed; assigning the transport roller of a contactless measuring speed sensor that measures an actual deduction speed of the glass tube strand in an area of the respective associated transport roller; and introducing a control- or regulating device of the measured actual deduction speed of the glass tube strand. The control- or regulating-device regulates/controls the peripheral speed of the transport roller to minimize or to control a difference between the actual deduction speed in the area of the respective associated transport roller and the peripheral speed of the transport rollers, which have wedge-shaped support surfaces. The peripheral speed of the transport roller is measured: in the area of a support point of the glass tube strand on the wedge-shaped support surface or at a plant- or measuring-point corresponding to the respective support point with the same peripheral speed; and without contact by a laser-Doppler-measuring method or touching by a speed-measuring roller contacting the respective transport roller. The support point of the glass tube strand is optically detected on the support surface. A position of a measuring range is varied on the support surface. The control- or regulating-device is a function of the measured peripheral speed of a controlled variable to the drive unit so that the difference between the actual measured peripheral speed in the range of the transport roller and the peripheral speed of the transport roller is controlled to a zero value. The control- or regulating-device of the control variable or a correction value for the control variable in dependence of sizes is calculated as the measured actual deduction speed of the glass tube strand, temperature in the range of the transport roller, outer radius of the transport roller, position of the support point on a support surface of the transport roller, linear expansion coefficient of a glass material of the glass tube strand, position of the transport roller along a drawing path for removing the glass tube strand. The calculated control variable is displayed to the drive unit to control the peripheral speed of the respective associated transport roller or the transport rollers, which are: divided by a coupling device in a row of groups of the transport rollers whose peripheral speed is regulated or controlled in groups corresponding to a standard- or control-variable; and arranged in a region in which the temperature of the glass tube strand above a solidification temperature of the glass material of the glass tube is 350[deg] C. The temperature of the glass tube strand is measured at a first transport roller of the transport rollers with which the temperature of the glass tube strand is cooled to the solidification temperature of the glass material of the glass tube strand. The peripheral speed of the transport rollers is controlled or regulated corresponding to a thermal linear contraction of the glass tube strand and the respective position of each transport rollers with which the temperature of the glass tube strand is measured. Independent claims are included for: (1) a computer program product; and (2) an apparatus for controlling the peripheral speeds of transport rollers of a glass tube manufacturing plant.