Abstract: A method of lubricating the roller bearings journaling the rotatable, vibration imparting, eccentric mass in the closed cavity of a vibratory compactor housing comprising the step of providing a layer of lubricating oil at the bottom of the housing cavity having its upper surface spaced below but relatively close to the nadir point of the circular path of travel of the maximum radially extending node portion of the eccentric mass about its eccentric axis of rotation whereby to prevent penetration of the node portion directly into the oil layer itself and instead permitting the impacting of the node portion only with the upstanding thin columns of oil which are continuously formed at the upper surface of the oil layer, during the vibration of the housing and oil layer, to thereby splatter the oil from the impacted oil columns upwardly within the housing and into the roller bearings.

Abstract: An improved ripper using a hydraulic hammer with a rotating long service life hammer tool is provided. The tool is cylindrical with a large cylindrical upper portion and a central portion of reduced diameter. The tool is retained in the hammer by means of a pin passing through the tool cavity of the hammer housing which prevents passage of the large upper portion.