| 摘要 |
In a device for controlling vibration conveyors or the like it is proposed to drive the vibration generators in the form of magnets driving the respective vibration conveyors via a phase-angle controller, which receives its firing pulse fed from a digital drive circuit driven by a supervisory programmable controller. The digital drive circuit decodes the digital command word fed to it, which is then preferably transferred into a latchable memory, when an additional selective transfer signal (strobe) arrives and converts this via a time stage into a time delay synchronised with the mains frequency, after expiry of which delay the main triac of the phase-angle controller is released for firing. The decoder comprises a diode resistor matrix which, as an RC element having a capacitor, presets different charging times for the capacitor according to the digital control word fed to it; these charging times are detected by a threshold discriminator circuit and used for triggering the main triac.
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