Patents by Inventor David August Horsma

David August Horsma 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: 4095044
    Abstract: A splice case is disclosed providing sealed protection for splices such as in telephone cable situated in adverse environmental conditions. The case includes a shell defining a cavity for enclosure of a splice. The shell is longitudinally split and includes openings at the ends thereof along the longitudinal split for receiving incoming cable. Thermally responsive sealant extends along the longitudinal split and a heating element is provided for causing the sealant to effectively seal the enclosed splice. A multiple cable adapter of thermally responsive sealant is sized to fit within a cable opening in the splice case and includes a plurality of longitudinally extending channels for accommodation of multiple incoming cables. Sheets of material exhibiting high thermal conductivity extend from the adapter such that the heat of the heating elements may be conveyed to the body of the adapter.
    Type: Grant
    Filed: October 26, 1976
    Date of Patent: June 13, 1978
    Assignee: Raychem Corporation
    Inventors: David August Horsma, Francis De Blauwe
  • Patent number: 4085286
    Abstract: A heat recoverable article is so configured that it can be positioned around a pipe or cable joint or splice which it is desired to encapsulate or seal. Means for sealing a splice involving a plurality of cables of the same or varying sizes are provided. The article includes a closure means for holding the article together after it has been positioned around the splice to be sealed. In a preferred embodiment, the inner surface of the article contains a heat activated adhesive or sealant to environmentally encapsulate the splice and the outer layer of the article is a heat recoverable insulating material. In a particularly preferred embodiment, the article has self-contained heating means, which heating means comprises a polymeric material having dispersed therein a conductive filler, said heating means exhibiting a positive temperature coefficient of resistance so as to render it self-regulating.
    Type: Grant
    Filed: August 4, 1975
    Date of Patent: April 18, 1978
    Assignee: Raychem Corporation
    Inventors: David August Horsma, Stephen Hunter Diaz
  • Patent number: 4017715
    Abstract: Described herein are self-regulating heating articles. The article comprises a constant wattage layer and a layer that exhibits a positive temperature coefficient of resistance (PTC layer). At its steady state condition, the heater is self-regulated by the switching or anomaly temperature T.sub.s of the PTC layer. However, the constant wattage layer has a higher resistance at temperatures below T.sub.s and heats first when the article is connected to a source of electrical power. Means are provided to impede the temperature increase in the PTC layer caused by the heating of the constant wattage layer so that it can heat above T.sub.s before the PTC layer rises to T.sub.s and reduces the current flow to the heater. Further increases in temperature render the PTC layer, for most purposes, non-conductive.
    Type: Grant
    Filed: August 4, 1975
    Date of Patent: April 12, 1977
    Assignee: Raychem Corporation
    Inventors: Wells Whitney, David August Horsma