| 摘要 |
<p>A light and practical pulley block comprises a pulley (1), which is freely rotatable placed on an axle (2), which is mounted within a casing (3) formed of two parts (31, 32), which are arranged apart from each other and are at certain distance apart from said pulley (1) connectable with each other by means of a connecting member (30), which is at a sufficient distance apart from said pulley (1) insertable into appropriate bore (310, 320) on each of said parts (31, 32) of the casing (3) and is in its inserted state protected against undesired removal. Each of said parts (31, 32) comprises an uniform reinforcing grid (33) consisting of metallic material as well as a liner (34) consisting of non-metallic material, by which said reinforcing grid (33) is covered at least on the external surface faced away from said pulley (1), wherein said grid (33) consists of a bearing area (335), which is formed of primary and secondary bearing rings (331, 334) which are connected with each other by means of longitudinal bearing strips (335', 335") as well as of a protecting ring (332), by which said primary bearing ring (331) is connected via plurality of radially extending spokes (333), so that the primary ring (331) is arranged concentrically with said protecting ring (332), the diameter of which is larger than the diameter of the pulley (1), and is surrounded therewith, and wherein said grid (33) further comprises a pair of external spokes (336', 336") extending each per se tangentially with respect to said protecting ring (332) and towards said secondary bearing ring (334), namely towards each junction between the last and each belonging longitudinal bearing strip (335', 335") of the bearing area (335) of the bearing grid (33) of the pulley block.</p> |
