| 摘要 |
A pipe wrench/ wrench consisting of a shank with an involute jaw and a loose jaw pivotally connected hereto which can be plane or consist of planes forming angles to each other. The jaws can be toothed. The centre of the circle belonging to the involute lies on or close to the axis of rotation. During the relative rotation of the jaws, the point of the involute (relative to the loose jaw) which touches pipes of a diameter corresponding to the jaw gap will always lie on the same straight or almost straight line as intersects the involute at right angles, and it is possible to use either the concave or the convex side of the involute as jaw face. Pipes which are actuated will, at intervals of approx. 120`, receive a chiefly radially directed normal force K which is proportional to the moment actuating the pipe, irrespective of the pipe diameter. |
