Hydraulic excavator boom mounted draw cylinder - has rollers in side pieces raised from lower chord when bolt is driven

摘要

A plate carrying a hydraulic cylinder, with bottom coupling is connected to a boom on an excavator by a bolt passing through aligned holes. At its top the cylinder (14) swivels about an axis (26) at right angles to the bolt. Rollers are mounted inside the jaws above the connecting traverse, to run on the protruding edges (11) of the lower chord of the boom (2) with the bolt released. Holes in the jaws are at such a level that the rollers are raised when the bolt is driven home. There is a fixture device for the extended cylinder below the boom. The cylinder operates in tension is sited when at rest so as not to damage the boom, nor limits its area of swivel.