| 摘要 |
The device has a spray tube (14) which conducts a powder jet (P), electrodes (25, 26) having free ends (25', 26') being provided at the outlet end (22) of the spray tube (14) directed towards the axis (27) thereof, which electrodes are at different high voltage potentials of the same polarity. The electrodes (25, 26) are arranged in an end region of the spray tube (14) recessed to a greater internal diameter (22) and their free ends (25', 26') lie outside a cylindrical surface continuing the smaller internal diameter (21) of the spray tube (14). Between the smaller (21) and the larger (22) internal diameter of the spray tube (14) is provided a sharp detachment edge (23). The electrodes (25, 26) can be arranged at an incline in the same orientation to the flow direction of the powder jet (P). Likewise, in the transition region between the smaller and the larger internal diameter (21 and 22) in the spray tube (14), through-ways can be provided which favour a secondary flow of air keeping the electrodes clean. This device makes the electrostatic charging of individual powder particles more uniform and reduces the wear of the electrodes by abrasion. <IMAGE>
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