| 摘要 |
<p>An anti-sticking cut-off system for vacuum die-casting includes a cut-off valve (1), an extraction unit (3) for sucking air in the cut-off valve (1) and an oil-way residue-cleaning unit (2). The cut-off valve (1) includes a driven valve core (103) and a driving valve core (102). The upper part of the driven valve core (103) is a seal part (110), the middle part is a guide part (111) provided with a scraper groove (101) and the lower part is a linkage part (112). A cone part (113) is provided between the seal part (110) and the guide part (111). A driven valve core orifice (114) above the oil way of the cut-off valve (1) is a stepped orifice which includes a large diameter orifice (115) and a small diameter orifice (116). The diameter of the large diameter orifice (115) is greater than that of the small diameter orifice (116) in the range of 0.02-0.15mm. The small diameter orifice (116) is matched with the guide part (111) of the driven valve core (103) to prevent molten metal from entering. The large diameter orifice (115) can reduce the force which prevents the driven valve core (103) from moving up, so as to avoid breaking the linkage mechanism. The anti-sticking cut-off system for vacuum die-casting enhances the reliability and the sensitivity of the cut-off valve (1).</p> |
