Patents Assigned to Pedershaab A/S
  • Patent number: 5910325
    Abstract: A system for the molding of tubular goods, comprising at least one mold having an inner mold part and an outer mold part which together define a mold cavity and an upwardly open annular pouring gate, the system additionally comprising a plurality of vibrators and devices for lifting the vibrators from and lowering these into the mold cavity through the annular pouring gate. The positioning devices are adapted to displace the vibrators radially with respect to the annular pouring gate, and each of the positioning devices is provided with a separate controllable drive unit which is adapted to displace the vibrators individually. This results in a more flexible system for the molding of tubular goods which may be adapted to various pipe types, such as egg-shaped, four-sided, circular and other forms.
    Type: Grant
    Filed: December 18, 1997
    Date of Patent: June 8, 1999
    Assignee: Pedershaab A/S
    Inventor: Johannes Hvidegaard
  • Patent number: 5648108
    Abstract: A production system for automatically casting hollow bodies, in particular of concrete, in a casting mold, which comprises an inner mold (2), an outer mold (1), a bottom ring (3), and a top ring (4). Separate top rings (4) are used for the production, which remain on the top end of the pipe until the concrete has set sufficiently, to ensure that the shape and tolerances of the top end of the pipe are retained after casting. The system moreover includes a clamping chuck (15) for retaining the top ring during casting. The clamping chuck is equipped with a clamping device that includes a ring-shaped flexible hose and a slotted spring ring. When the hose is filled with compressed air from a compressed air source, it clamps the spring ring together around a gripping ring on the top ring.
    Type: Grant
    Filed: August 7, 1995
    Date of Patent: July 15, 1997
    Assignee: Pedershaab A/S
    Inventor: Johannes Hvidegaard
  • Patent number: 5449283
    Abstract: A machine serves to cast pipes of concrete or a similar material substantially vertically. The machine includes an inner mould part (2) and an outer mould part (12). These mould parts are displaced axially with respect to each other during the casting process. A vibrator is preferably provided upwardly in the inner mould part (2), and an axially journalled distributor wheel (1) is rotatably mounted on the top of the mould part (2) the distributor wheel (1) having a plurality of blades (4) for distributing the material in the ring gap between the two mould parts (2, 12). The distributor wheel (1) and its mount are constructed so stiffly that the vibrations generated by the vibrator are transmitted to the material through the blades of the wheel. This ensures, when a firm profile ring is used for the casting of the spigot end, that area of difficult access below said ring is filled completely with concrete, and that the concrete obtains the prescribed quality.
    Type: Grant
    Filed: January 28, 1994
    Date of Patent: September 12, 1995
    Assignee: Pedershaab A/S
    Inventor: Bent Herrmann