Method and apparatus for the sealing of glass tubes in a hot softened state
AssigneeSchott AG
InventorsFranz Voelkl, Albert Schmid, Thomas Schirmel, Heinz-Josef Henke, Carsten Haman
Life of this patent
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Abstract
A method for the sealing of glass tubes in a hot softened state is provided. The method includes softening the glass at a severing zone adjacent to an end portion of the glass tube and rotating the glass tube about its longitudinal axis while being heated until a hot softened state is reached in which the end portion is severed off. The hot softened end portion of the glass tube can be pulled-off from the severing zone by a pulling-off device in such a way that the glass tube is simultaneously heat sealed at the severing zone during the severing process.
Claims11
A method for the sealing of glass tubes in a hot softened state, comprising:
- softening the glass tube at a severing zone near an end portion of the glass tube,
- conveying the glass tube at a predetermined speed transverse to its longitudinal axis along a pulling device, and
- rotating the glass tube about its longitudinal axis while the end portion is pulled off from the severing zone by means of the pulling device in such a manner that the glass tube is sealed by fusion at the severing zone, wherein
- the pulling device is rotationally fixed or rotates at an angular speed which is different to the angular speed of the glass tube, and
- the pulling device is moved in correspondence to the movement of the glass tube transverse to the longitudinal axis while the end portion is pulled off from the severing zone;
- wherein the glass tube is put into a rotation about the longitudinal axis by rolling on at least one stationary supporting strip, to be conveyed transverse to the longitudinal axis along the pulling device in a rolling forward movement.
The method according to claim 5, further comprising:
- detecting the diameter and/or the movement of the glass tube transverse to the longitudinal axis and/or the type of the glass tube to be sealed is detected by a sensor;
- and
- controlling the pulling-off trajectory by the controlling device based on the detected diameter and/or on the detected movement of the glass tube transverse to the longitudinal axis and/or on the detected type of the glass tube to be sealed.
An apparatus for the sealing of glass tubes in a hot softened state, comprising:
- a heating device configured for softening an end portion of the glass tube,
- a conveying device configured for conveying the glass tube transverse to the longitudinal axis of the glass tube along the heating device, and
- a pulling device configured for pulling off an end portion of the glass tube softened by the heating device, wherein
- the conveying device is further configured for rotating the glass tube about its longitudinal axis while it is conveyed along the heating device, and
- the pulling device is rotationally fixed or rotates at an angular speed which is different to the angular speed of the glass tube, for pulling off the softened end portion from the glass tube in such a manner that the glass tube is sealed by fusion at the severing zone, wherein
- the conveying device comprises a plurality of contact pins, which contact the glass tube in sections, for pushing the glass tube along the heating device, and at least one stationary supporting strip on which the moving glass tube is supported and put into a rotation about the longitudinal axis by rolling on the supporting strip, to be conveyed transverse to the longitudinal axis along the pulling device in a rolling forward movement.
Dependencies are inferred from the claim text.