Patents by Inventor Jan Hrdina

Jan Hrdina has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Method of and apparatus for producing multicomponent spun-twisted yarns by open-end spinning
    Patent number: 4527384
    Abstract: A single-step stable method of producing spun-twisted yarns. A twist point is located on the frictional surface of a take-off funnel of the spinning rotor. A strand material which forms a component of the final spun-twisted yarn product is exposed, between feed rollers and said twist point, to an appropriate combination of transport effects of a pneumatic field of force and a mechanical field of force. For this purpose, the tube, through which the strand material is supplied, is determined in dependence on the pneumatic conditions prevailing in the spinning rotor.
    Type: Grant
    Filed: October 25, 1983
    Date of Patent: July 9, 1985
    Assignee: Vyzkumny ustav bavinarsky
    Inventors: Alois Stejskal, Zdenek Havranek, Miroslac Stepanek, Jan Hrdina, Frantisek Cada, Zelmira Borovcova, Jaroslav Slingr
  • Pressure control apparatus for hydromechanical drawing
    Patent number: 4419876
    Abstract: Device for the control of the pressure in the pressure chamber for the hydromechanical deep drawing of sheet metal in hydraulic presses wherein the pressure chamber constitutes the drawing die. The control system has at least one two-diametered piston transmitter mounted in a hydraulic cylinder which on the side of the smaller diameter of the piston of the piston transmitter is connected to the space of the pressure chamber and on the other, larger diameter side of the piston transmitter is provided with a supply line for the pressure medium. The control system may include several hydraulic cylinders with two-diameter piston transmitters, the volume of the parallel hydraulic cylinders at the side of the smaller diameters of pistons of the piston transmitters is equal to, or greater than, the volume of the pressing in the pressure chamber.
    Type: Grant
    Filed: December 12, 1980
    Date of Patent: December 13, 1983
    Assignee: Tovarny strojirenske techniky, koncern
    Inventors: Jindrich Spacek, Vaclav Smrcek, Karel Voda, Jiri Kosek, Jan Hrdina, Vaclav Penaz
  • Apparatus for separating fibers in open-end spinning machines
    Patent number: 3938310
    Abstract: Apparatus for separating fibers in open-end spinning machines, having a combing-out cylinder by which a fibrous sliver supplied by a feeding device is separated in a combing-out zone provided between a card clothing of the combing-out cylinder, and an operating wall of an insert, the cross-section of said zone decreasing, at least in the introductory portion thereof, in the fiber flow direction while the separated and combed-out fibers are conveyed through a duct into a rotary spinning chamber. The insert is provided with at least two differenly concave faces for providing different combing-out zones, said insert being adjustable into positions in which any of said concave faces is adapted to cooperate in providing the combing-out zone, the insert being held in a desired one of its respective positions.
    Type: Grant
    Filed: March 4, 1974
    Date of Patent: February 17, 1976
    Assignee: Vyzkumny Ustav Bavlnarsky
    Inventors: Stanislav Didek, Jaroslav Storek, Miloslav Kubovy, Zdenek Svec, Jan Hrdina, Jaromir Kasparek