Patents Assigned to H. Bieri AG, Liebefeld
  • Patent number: 4151860
    Abstract: Electromagnetically actuable hydraulic control valve with a valve housing in which a series of valve bodies are disposed in control bores for longitudinal displacement between at least two shift positions, and with a pot electromagnet disposed on the valve housing. The valve has an armature in the form of a large-area, substantially flat plate provided between the pot electromagnet and the valve housing, to which armature at least a part of the valve body ends protruding from the valve housing are attached. The armature plate is provided on its flat side confronting the valve housing with a guide shaft protruding at right angles and guided in a slidingly displaceable manner in a bore in the valve housing.
    Type: Grant
    Filed: September 22, 1977
    Date of Patent: May 1, 1979
    Assignee: H. Bieri AG Liebefeld
    Inventor: Karel Chromik
  • Patent number: 4131126
    Abstract: A mechanical actuating device for hydraulic control valves having complex control functions, which can be assembled from individual units in a modular system, each of which has valve bodies which can be operated by longitudinal displacement in a housing that can be joined to the housing of the adjacent module. The actuating device for each module has a cam control member rotatably mounted in a cam housing which can be placed on the module housing and which can be brought into engagement with the ends of the valve bodies protruding from the module housing. The cam control members of all individual modules are disposed with aligned axes of rotation, and a coupling is provided for the co-rotational joining together of the cam control members of adjacent modules in selectable relative angular positions to one another.
    Type: Grant
    Filed: September 22, 1977
    Date of Patent: December 26, 1978
    Assignee: H. Bieri AG Liebefeld
    Inventor: Karel Chromik
  • Patent number: 4026602
    Abstract: An apparatus designed especially for mechanically breaking up reinforced concrete and comprising a cylinder containing a hydraulically-operated piston connected to a thrust wedge and acting upon two insertion pieces to be inserted in a borehole in the reinforced concrete or in stone. In order to avoid excessive wear and tear on the components by reducing the stresses to which they are subjected, the apparatus comprises a bracing part rigidly joined to the cylinder by tie plates, and the two end faces of the insertion pieces remote from the cylinder are braced against this bracing part, through which the thrust wedge passes when the apparatus is in operation. Thus the end faces of the insertion pieces can slide on the surface of the bracing part when they are driven apart by the advancing wedge.
    Type: Grant
    Filed: January 12, 1976
    Date of Patent: May 31, 1977
    Assignee: H. Bieri AG, Liebefeld
    Inventor: Hans Bieri