Patents Assigned to Rewatec AG
  • Patent number: 5357771
    Abstract: To permit the use of combustible and potentially explosive solvents used in dry-cleaning operations, based on hydrocarbon compounds, the dry-cleaning machine is formed with an explosion-resistant housing (8) surrounding a perforated, rotatable drum (1) into which the goods are introduced. After carrying out the normal dry-cleaning procedure, and draining of dry-cleaning solvent, a vacuum pump generates an under-pressure, in the order of below 500 mbar, and preferably about 230 mbar, while heating the mixture to effect drying. A cooling coil, located at a lower portion of the machine, provides for condensation of solvent out of the solvent-air mixture and, after the major portion of the solvent has been evaporated, the heat exchanger is switched over to cooling for final condensation of any remanent solvent. The vacuum continues to be maintained, so that the boiling point of solvent, due to the under-pressure, is lowered by at least 40.degree. C., and preferably 50.degree. C.
    Type: Grant
    Filed: October 28, 1993
    Date of Patent: October 25, 1994
    Assignee: Rewatec AG
    Inventor: Ulrich Schaal
  • Patent number: 5301379
    Abstract: To permit the use of combustible and potentially explosive solvents used in dry-cleaning operations, based on hydrocarbon compounds, the dry-cleaning machine is formed with an explosion-resistant housing (8) surrounding a perforated, rotatable drum (1) into which the goods are introduced. After carrying out the normal dry-cleaning procedure, and draining of dry-cleaning solvent, a vacuum pump generates an under-pressure, in the order of below 500 mbar, and preferably about 230 mbar, while heating the mixture, to effect drying. A cooling coil, located at a lower portion of the machine, provides for condensation of solvent out of the solvent-air mixture, and, after the major portion of the solvent has been evaporated, the heat exchanger is switched over to cooling for final condensation of any remanent solvent. The vacuum continues to be maintained, so that the boiling point of solvent, due to the under-pressure, is lowered by at least 40.degree. C., and preferably 50.degree. C.
    Type: Grant
    Filed: July 21, 1992
    Date of Patent: April 12, 1994
    Assignee: Rewatec AG
    Inventor: Ulrich Schaal