Upper extraction unit removing gaseous emissions from laser machining equipment, has suction hood formed by upper and lower casings held together by magnets and locking screws

摘要

Upper and lower casings (6, 11) constitute a suction hood (2). This has a common joint line with vertical, angled and horizontal sections (17, 18, 19). The joint line runs along the suction channel formed by the casings. Along each section of the joint line, the casings have gap-free mating surfaces. The horizontal circular suction inlet in the lower casing (11) concentrically-surrounds the laser nozzle. The suction hose (4) extracting emissions, is accommodated over the vertical mating surface (18) of the casings. Only the lower casing is removed for cleaning, whilst the upper casing remains permanently connected to the nozzle support column, the optic holder and the optic head (1). The entire suction channel has approximately constant cross sectional area. The upper casing presents smooth angled and horizontal surfaces without recesses, to the suction channel. The nozzle support column and nozzle have smooth surfaces without recesses. At each end of the hood, pairs of magnets disposed on centre lines are complimented by location pegs and matching holes. These hold and locate the casings together detachably. The casing assembly is consolidated by locking screws (12). The suction can be adjusted using a bypass slide (16) to a level suitable for each particular application. When this slide is opened, ambient air is admitted, reducing the suction around the laser nozzle.