Patents by Inventor Pavel Kafunek

Pavel Kafunek 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).

  • Patent number: 4188996
    Abstract: There is disclosed a liquid cooler for semiconductor power elements, the cooler having an external surface for bearing against the cooled element. The internal space of the cooler is formed so as to generate a whirling motion of the cooling medium supplied thereto.
    Type: Grant
    Filed: May 3, 1978
    Date of Patent: February 19, 1980
    Assignee: CKD Praha, oborovy podnik
    Inventors: Michal Pellant, Jaroslav Zuna, Petr Novak, Zdenek Zavazal, Jindrich Kratina, Pavel Reichel, Pavel Kafunek
  • Patent number: 4183042
    Abstract: A power semiconductor device for efficient heat dissipation. The construction eliminates a loose contact between the semiconductor element and a cooling jig.
    Type: Grant
    Filed: February 10, 1978
    Date of Patent: January 8, 1980
    Inventors: Petr Novak, Jaroslav Pellant, Jaroslav Zuna, Jindrich Kratina, Pavel Reichel, Pavel Kafunek
  • Patent number: 4129881
    Abstract: An improved construction for a two or three terminal power semiconductive device provides efficient thermal and electrical conduction between the heat-generating semiconductive wafer and the associated terminal electrodes with the use of a permanent, flowable thin layer of liquid metal therebetween. The liquid metal is carried in annular reservoirs within the outer surfaces of the terminal electrodes confronting the planar surfaces of the wafer, and serve to conduct the heat from the wafer to a hollow heat-dissipating well within the terminal electrodes. The wall of the well is made porous or is otherwise configured or reinforced to effectively increase the surface area thereof to aid in heat dissipation. If desired, an auxiliary seal-bearing groove is disposed concentric with and radially inwardly of the reservoir on at least one of the terminal electrodes, such groove bearing an O-ring or similar seal which bears against the confronting surface of the wafer to confine the flow of the liquid metal layer.
    Type: Grant
    Filed: March 18, 1977
    Date of Patent: December 12, 1978
    Assignee: CKD Praha, oborovy podnik
    Inventors: Pavel Reichel, Pavel Kafunek, Jiri Kovar, Oldrich Pokorny, Jaroslav Zuna, Jindrich Kratina, Michal Pellant
  • Patent number: 4104677
    Abstract: A flat surface of a planar power semiconductive element, such as a thyristor or diode, is adjustably urged downwardly against a heat sink in electrical and thermal contact therewith by means of a spring-loaded eccentric element. The spring extends transversely over the opposite surface of the semiconductive element between a pair of anchor members carried by the heat sink. The eccentric is secured to an intermediate portion of the transversely extending spring, and is adapted to rotate in a vertical plane whereby successive portions of the eccentric periphery are urged with different pressures downwardly against the opposed surface of the semiconductive element, either directly or through an insulating spacer element. If desired, a pair of flattened abutment areas may be established on diametrically opposed portions of the eccentric periphery to correspondingly define a two-position stable adjustment of the bearing pressure.
    Type: Grant
    Filed: November 26, 1976
    Date of Patent: August 1, 1978
    Assignee: CKD Praha, oborovy podnik
    Inventors: Jiri Kovar, Pavel Kafunek, Pavel Reichel, Oldrich Pokorny, Michal Pellant, Jindrich Kratina, Jaroslav Zuna
  • Patent number: 4037246
    Abstract: A high-power semiconductive device having a conductive liquid for maintaining contact between the active semiconductive element and the associated current supply and feeding facilities is described. A resilient insulating ring disposed in contact with the periphery of the active semiconductive element is contacted on respectively opposite sides by a pair of heat-conductive tubes that serve as the current supply elements of the device. A pair of conductive plates disposed on opposite sides of the semiconductive element are secured to the sides of the heat-conductive tubes to close off a pair of mutually insulated chambers which are bounded on the other side by the terminal areas of the semiconductive element. The conductive liquid is disposed in each of the so-defined chambers to provide thermal and electrical contact between the heat-conductive tubes and the terminal areas of the semiconductive element.
    Type: Grant
    Filed: July 16, 1975
    Date of Patent: July 19, 1977
    Assignee: CKD Praha, oborovy podnik
    Inventors: Michal Pellant, Oldrich Pokorny, Pavel Reichel, Jaroslav Zuna, Pavel Kafunek, Jindrich Kratina
  • Patent number: 3989095
    Abstract: A semi-conductor cooling system formed of a container having a wall portion made of soft yieldable material which is adapted to contact the surface of a semi-conductor device. A porous member is disposed within the container adjacent the inner surface of the yieldable wall. A liquid medium partially fills the remainder of the chamber immersing at least a portion of the porous member. The latent heat of the semi-conductor device is dissipated via the porous member in a closed evaporator-condensing cycle.
    Type: Grant
    Filed: July 17, 1975
    Date of Patent: November 2, 1976
    Assignee: CKD PRAHA, oborovy podnik
    Inventors: Bohuslav Voboril, Pavel Reichel, Pavel Kafunek
  • Patent number: 3952797
    Abstract: A semi-conductor cooling system formed of a container having a wall portion made of soft yieldable material which is adapted to contact the surface of a semi-conductor device. A porous member is disposed within the container adjacent the inner surface of the yieldable wall. A liquid medium partially fills the remainder of the chamber immersing at least a portion of the porous member. The latent heat of the semiconductor device is dissipated via the porous member in a closed evaporator-condensing cycle.
    Type: Grant
    Filed: December 21, 1973
    Date of Patent: April 27, 1976
    Assignee: CKD Praha, oborovy podnik
    Inventors: Bohuslav Voboril, Pavel Reichel, Pavel Kafunek