Patents Examined by Edward K. Lock
  • Patent number: 4841842
    Abstract: There is described apparatus for scabbling concretw which includes a hollow cylinder block having a top and bottom plate between which plates there is provided a smooth sided hollow cylindrical cylinder liner. The piston for reciprocation within the cylinder liner is also provided.
    Type: Grant
    Filed: September 5, 1986
    Date of Patent: June 27, 1989
    Assignee: John MacDonald & (Pneumatic Tools) Ltd.
    Inventor: David T. Allan