Dividing low-pressure discharge lamps e.g. cold cathode tubes, by dividing glass tube and opened and gas-filled interior space of glass tube into parts, and heating tube in melting zone provided at point of separation by heating device

摘要

The method comprise dividing a glass tube (2) of a low-pressure discharge lamp and a closed and gas-filled interior space (2) of the glass tube into divided parts, where the gas-filled interior space is opened, and heating the glass tube to a melting temperature in a melting zone provided at a point of separation (5) by a heating device (4), where the melting temperature is lower than glass of the tube. The heating step is performed by heating the glass tube until the molten glass in a break zone forms a compact glass body (6) without the gas-filled interior space. The method comprise dividing a glass tube (2) of a low-pressure discharge lamp and a closed and gas-filled interior space (2) of the glass tube into divided parts, where the gas-filled interior space is opened, and heating the glass tube to a melting temperature in a melting zone provided at a point of separation (5) by a heating device (4), where the melting temperature is lower than glass of the tube. The heating step is performed by heating the glass tube until the molten glass in a break zone forms a compact glass body (6) without the gas-filled interior space. The break zone and the closed, gas-filled interior space are separated from each other. The compact glass body in the break zone is separated by further heating and/or a mechanical force. The heating device comprises a laser, and the glasses of the glass tube in the melting zone are melted by a laser radiation unit. The laser and/or the glass tube and lasers are positioned relative to each other. The melting zone and the separation point of the glass tube (2) are present in a scattering zone of the laser so that the laser dividing and melting of glasses of the glass tube in the melting zone are produced. The heating device further comprises a gas burner so that glasses in the melting zone of the glass tube are melted by gas flame. The gas burner includes a combustible gas, in particular hydrogen as a fuel that is supplied and ignited by an igniter. The gas burner and the glass tube are positioned relative to each other such that the melting range and the separating point of the glass tube are spaced from the heat center of the gas flame. The heating device comprises hot pliers so that glasses of the glass tube are melted by transfer of heat by the hot pliers. The hot pliers heat the glass tube until the molten glass in a break zone forms a compact glass body without the gas-filled interior space. An independent claim is included for a device for dividing low pressure discharge lamps.