Patents Assigned to Wittwer Construction Co., Inc.
  • Patent number: 4812088
    Abstract: A doweling tool for drilling a dowel hole in concrete to facilitate the insertion of dowels, the doweling tool having a guide bar, a support frame for supporting the guide bar, a carriage movingly connected to the guide bar, a pneumatically operated drilling tool having a drill bit connected to the carriage and a pneumatic cylinder having a portion connected to the support frame and another portion connected to the carriage. The pneumatic cylinder is operable to move the carriage and the drilling tool connected thereto in a forward direction for drilling the dowel hole and for moving the carriage and the drilling tool connected thereto in a reverse direction for withdrawing the drilling tool from the dowel hole. The carriage is rollingly supported on the guide bar by a roller assemblies for rolling movement in the forward and reverse direction.
    Type: Grant
    Filed: January 23, 1987
    Date of Patent: March 14, 1989
    Assignee: Wittwer Construction Co., Inc.
    Inventor: Leon M. Hake