Abstract: A laser fusion welding device includes a 1.9 ?m laser light source, a control unit and a light spot adjusting device. The control unit is configured to control the laser light source and the light spot adjusting device to adjust a laser power density at an object to be subjected to fusion welding. The 1.9 ?m laser light source has output power of 100-500 W. The control unit includes a time control unit, a power control unit and a light spot control unit. The time control unit is configured to control a turn-on time of the laser light source. The power control unit is configured to control the output power of the laser light source. The light spot control unit is configured to control the light spot adjusting device to adjust a size of a light spot at the object to be subjected to fusion welding.

Abstract: The present disclosure discloses a filter element paper component, including two frames, wherein the two frames are oppositely arranged and are not connected; filter element paper, wherein two ends of the filter element paper are fixedly connected to the corresponding frames respectively, and the two frames separately locate the two ends of the filter paper during mounting; and a separation strip, detachably connected between the two frames to form a complete hollow cavity. The filter paper is folded and arranged in the cavity. The separation strip is pulled to be respectively separated from the two frames, and the two frames arranged at the two ends of the filter element paper are separately pulled to unfold the filter element paper.