Ballast for a hand soldering device or a station soldering device with a soldering tip, comprises a controllable voltage converter to convert an input line voltage to an AC voltage that is supplyable to a transformer, and a detection unit

摘要

The ballast (4) for a soldering device (1) such as a hand soldering device or a station soldering device with a soldering tip (2), comprises a controllable voltage converter (5) for converting an input line voltage to an AC voltage that is supplyable to a transformer, and a detection unit provided at a secondary side from the transformer for detecting a zero-crossing, where a signal output of the detection unit is connected with an input of a control unit. A filter is arranged downstream to the transformer, and comprises a current-compensated choke and Y-condenser. The ballast (4) for a soldering device (1) such as a hand soldering device or a station soldering device with a soldering tip (2), comprises a controllable voltage converter (5) for converting an input line voltage to an AC voltage that is supplyable to a transformer, and a detection unit provided at a secondary side from the transformer for detecting a zero-crossing, where a signal output of the detection unit is connected with an input of a control unit. A filter is arranged downstream to the transformer, and comprises a current-compensated choke and Y-condenser. A temperature of the soldering tip is determined by the control device, where the voltage converter is switchable and/or regulatable by the control device depending of the temperature of the soldering tip and/or signals of the detection unit. The voltage converter is operatable with variable frequency and/or variable duty cycle and a consumer voltage of the soldering device is regulatable with variable frequency and/or variable duty cycle. The transformer is formed as a transformer with sectional winding structure. The detection unit is formed as Y-condenser. The soldering tip is galvanically or capacitively connected with an earth potential. The voltage converter is switched on or switched off by the control device in the zero-crossing, so that the soldering device is supplyable with a number of complete half-cycles of a sinusoidal AC voltage. The voltage converter is formed as a resonant converter or a quasi-resonant converter. The detected zero-crossing is a voltage zero crossing, a current zero crossing or a zero crossing of an envelope curve of the voltage or current. A pulsed voltage is supplyable to the voltage converter, where the voltage converter has an active power factor correction. The ballast has a further detection unit, which is provided for determining the amplitude of the line voltage and based on which a working way and/or an input voltage range of the voltage converter is selectable by the control device, a standby current supply, in which only the control device is switched on and the voltage converter is switched off, and a protection device, over which the input line voltage is supplyable to the voltage converter.