| 摘要 |
<p>A shear for cutting bar stock includes upper and lower cutting blade supports each having a cutting blade, and a hold-down member, all pivotally connected about a working bearing. This assembly is pivotally mounted about a second bearing or pivot axis on one end of a frame of the shear, and is height-adjustable by a lockable hydraulic actuator attached to the upper cutting blade support at the opposite end of the shear, to provide vertical adjustability of the cutting point with minimal horizontal or angular displacement thereof. Preferably, the two pivot axes and the cutting point are coplanar. The upper cutting blade support is pivoted relative to the lower one by a hydraulic actuator engaging the upper support at one upper part thereof which is not so coplanar, to provide both a relatively long lever arm and a relatively long cutting arm for minimizing arcuation of the cutting movement. One cutting blade is adjustable within its support for optimum positioning taking into account the shape of the stock. The hold-down member is hydraulically locked into position with the lower (thrusting) cutting blade and moves therewith relative to the upper (contact) cutting blade, providing a three-point support to yield a clean cut.</p> |
