Abstract: A wear resisting span lock system for bascule bridges includes a normally-inactive hydraulic lockbar shoe expander operable to minimize sliding engagement of the lockbar with its guiding and receiving shoes only during bridge opening and closing operations.
Abstract: A span lock system for a double-leaf drawbridge. A guide housing mounted at the tip of one leaf includes an opening with vertically opposed cushioned shoes slidably supporting an elongate lock bar reciprocative lengthwise in a direction along the length of the drawbridge. A receiver housing mounted at the tip of the other leaf is positioned to interlock with the guide housing and includes a like opening slidably receiving the lock bar between vertically opposed cushioned shoes. A pair of vertical guide columns project from both side of the guide housing opening with the upper and lower edges of the distal sides beveled inwardly, and another pair of vertical guide columns project from both side of the receiver housing opening with the upper and lower edges of the proximal sides beveled outwardly.
Type:
Grant
Filed:
August 16, 2002
Date of Patent:
March 9, 2004
Assignees:
City of Chicago, Steward Machine Co., Inc.
Abstract: A drawbridge span lock system in which a locking bar longitudinally slides between wear shoes in each of guide and socket assemblies. The wear shoes are pre-loaded to a selected level by springs within the assemblies to maintain continuous contact of the shoes with the locking bar under no-load operating conditions of the bridge. Threaded adjusting carriers externally accessible in each assembly enable the springs to be precisely pre-loaded to any level within a design range.
Abstract: An energy absorbing span lock system for drawbridges, such as a double-leaf bascule leaf span. A retractable and extendible connector mounted on one leaf of the span engages a receiver on the other leaf. Resilient energy absorbing shoes in the receiver accept the connector and allow relative deflection between the leaf ends caused by vehicular traffic.