Patents Assigned to Freeze Master Limited
  • Pipe freezing apparatus
    Patent number: 5987906
    Abstract: A pipe freezing apparatus 2 has pipe freezer heads 12a, 12b supplied with refrigerant by a compressor 4. The freezer heads 12a, 12b comprise expansion chambers in which the refrigerant expands, to cool the heads. A valve 10 alternately diverts flow of the refrigerant to the freezer heads 12a, 12b. When a supply to a head 12a, 12b is shut off, the compressor lowers the pressure in the head, resulting in enhanced cooling when supply to the head is restored. The compressor 4 can be run continuously while the cooling at the heads is controlled.
    Type: Grant
    Filed: May 14, 1997
    Date of Patent: November 23, 1999
    Assignee: Freeze Master Limited
    Inventor: Trevor Hallett