Patents Assigned to Coxwold (Proprietary) Limited
  • Patent number: 4807318
    Abstract: This invention relates to an automatic pool cleaner, particularly suitable for domestic swimming pools which operate on the interruption of an induced flow of water through the cleaner and wherein the control of the interruption is effected through a tubular axially resilient diaphragm one end of which is closed and adapted to hold normally closed a passage from the head of the pool cleaner to the usual form of flexible hose connecting the pool cleaner to the filtration unit.
    Type: Grant
    Filed: October 21, 1987
    Date of Patent: February 28, 1989
    Assignee: Coxwold (Proprietary) Limited
    Inventor: Dieter H. F. Kallenbach
  • Patent number: 4642833
    Abstract: This invention relates to a valve assembly including a hollow body housing a tubular flexible diaphragm therein to provide a passage for fluid flow through the body. The assembly includes means whereby pressures within the diaphragm and in the chamber between the diaphragm and the hollow body are controlled so that, in use with fluid flowing through the diaphragm, it will be caused to automatically and repeatedly contract and expand. This will result in a pulsating flow of fluid through the assembly. Such a valve assembly finds particular application in a swimming pool cleaner operating off the reduced pressure provided by the pump for the conventional pool filtration plant and this invention includes a cleaner of this type including a valve assembly as set forth.
    Type: Grant
    Filed: June 28, 1985
    Date of Patent: February 17, 1987
    Assignee: Coxwold (Proprietary) Limited
    Inventors: Andries J. Stoltz, Dieter H. F. Kallenbach