| 摘要 |
In the first part of the current path, are at least two contacts partic. of the blade type (3), and both the contacts and the counter contact (4) have at least two contact surfaces (P1,P2;P1,P3,P4,P5), being able to be rotated so that the new contact surfaces (P2,P3,P4,P5) can be set into position in replacement of the old contact surfaces (p1). The counter contact is symmetrical in relation to both of its longitudinally directed central planes (B,D), the new contact surfaces (P2) being brought to locate against the contacts by rotating the counter contact around its longitudinal central axis. The contacts are symmetrical both in relation to their transversal central plane (E) and their two longitudinal central planes (F), so that the new contact surfaces (P3,P4,P5) locate against the counter contact by pivoting the contacts either around their longitudinal central axes or transversal central axes, or both. The counter contact pref. is a piece of a profile bar with longitudinal contact back formations contg. longitudinal lubrication tracks. |
