Extremely fast freezing, low-temperature blast freezer

{
  "publication_number": "US10660328B2",
  "country": "US",
  "kind": "B2",
  "title": "Extremely fast freezing, low-temperature blast freezer",
  "abstract": "A freezer includes a plurality of shelves in an insulated payload bay; a plurality of evaporators coupled to the payload bay with a multiplicity of coolant tubes in each evaporator, wherein each tube enters and then exits the payload bay, further comprising one or more cryogenic valves coupled to the coolant tubes; a pump to force coolant flowing through the evaporators with a pressure of at least 90 psi to supply the coolant at each evaporator with at least 80 gallons per hour of coolant; and a plurality of fans to circulate cooled air in the payload bay.",
  "claims": [
    "1. A system, comprising: a plurality of shelves in a payload bay surrounded by insulation acting as a thermal barrier between the payload bay and the outside environment; a plurality of evaporators coupled to the payload bay with a multiplicity of coolant tubes in each evaporator, wherein the coolant tubes cool the payload bay in parallel, further comprising one or more cryogenic solenoid valves coupled to the coolant tubes; a liquid nitrogen source to circulate a predetermined amount of coolant at a predetermined pressure to drive a predetermined coolant flow through the plurality of evaporators with coolant tubes and cool the payload bay to −150 degree Celsius in one hour; a thermal barrier isolating thermal flow between the payload bay and a main door where the thermal barrier comprises a gap with a non-metal material attached to both sides of the gap; an inner door and a pneumatic seal providing an airtight seal between the main door and the payload bay; a plurality of fans to circulate convective cooled air in the payload bay; and an external fan that forces air through a room heat exchanger.",
    "2. The system of claim 1, comprising one or more vent holes placed at predetermined locations on the payload bay.",
    "3. The system of claim 1, comprising a separate compartment located between the payload bay and the outside environment with an insulation of between 2 and 4 inches thick.",
    "4. The system of claim 1, comprising a controller coupled to a thermocouple inside the payload bay.",
    "5. The system of claim 4, wherein the controller performs proportional-integral-derivative (PID) control to maintain a set point within a predetermined limit.",
    "6. The system of claim 1, wherein the one or more cryogenic solenoid valves are located at an exhaust port.",
    "7. The system of claim 1, comprising one or more heating tubes within one or more evaporators.",
    "8. The system of claim 1, comprising a mechanical valve located in parallel with one or more cryogenic solenoid valves to manually regulate payload bay temperature.",
    "9. The system of claim 1, comprising a battery to provide backup power.",
    "10. The system of claim 1, wherein a safety valve is connected to one or more coolant tubes.",
    "11. The system of claim 10, wherein the safety valve has one or more heating fins or electrical heat tape coupled to it.",
    "12. The system of claim 1, comprising one or more pneumatic latches.",
    "13. The system of claim 12, wherein the one or more pneumatic latches and a rubber pneumatic seal are powered by gaseous nitrogen.",
    "14. A system, comprising: a liquid nitrogen inlet to receive liquid nitrogen; one or more coolant tubes that operate at a predetermined liquid nitrogen pressure; a payload bay; one or more evaporators inside the payload bay; one or more fans that distribute cooled air from the one or more evaporators to the payload bay; one or more vent holes; insulation surrounding the payload bay; a controller that maintains a temperature set point for the payload bay; a thermal barrier isolating thermal flow between the payload bay and a main door where the thermal barrier comprises a gap with a non-metal material attached to both sides of the gap; an inner door and a pneumatic seal providing an airtight seal between the main door and the payload bay; one or more pneumatic latches to secure a main door; and a rubber pneumatic seal that provides an airtight seal for the payload bay and the main door."
  ],
  "description_excerpt": "The present invention relates to high speed cooling freezers.\n\nMany applications require the specific capability of freezing a product in an extremely short time. Exemplary users include companies that require plasma or blood related products to be frozen quickly and completely to −40 C. Such companies contain their product in a multiplicity of specially formulated plastic bags that contain between 250 cc and 500 cc of plasma or blood related products. These companies may freeze up to 100 bags simultaneously, placing approximately 10 bags on a tray and up to 10 trays in the freezer. Traditionally, cooling devices known in the industry as Blast Freezers are used with the unique capability of freezing the customer's products at a substantially faster rate than standard laboratory or storage freezers.\n\nTypically, state of the art Blast Freezers are mechanical, with compressors and refrigerants. The main drawback is that the boiling point of the refrigerant is approximately −100 C which severely limits the ability to freeze product quickly. As an example, these freezers are unable to freeze a batch of 100 bags to −40 C in less than 2 hours. The present invention will perform that task in one hour, which is one-half the time of present day Blast Freezers. The freezer also has the capability of rapidly heating product to room temperature or higher.",
  "cpc": [
    "A01N 1/145",
    "A01N 1/0257",
    "F25D 17/06",
    "F25D 2700/122",
    "F25D 29/001",
    "F25D 29/006",
    "F25D 3/102"
  ],
  "ipc": [
    "A01N 1/02",
    "F25D 17/06",
    "F25D 29/00",
    "F25D 3/10"
  ],
  "assignees": [
    "Reflect Scientific Inc"
  ],
  "inventors": [
    "William G. Moon",
    "William J. Hancock",
    "Steven V. Boyce",
    "Steven J. Parkinson"
  ],
  "filing_date": "2018-08-25",
  "publication_date": "2020-05-26",
  "grant_date": "2020-05-26",
  "priority_date": "2009-05-12",
  "application_number": "US-201816112658-A",
  "family_id": "59561363",
  "cited_by_count": 2,
  "citations": [
    "US3678716A",
    "US4138049A",
    "US4436692A",
    "US4741172A",
    "US5163301A",
    "US5267443A",
    "US5287705A",
    "US5568800A",
    "US5826432A",
    "US5699670A",
    "US6349547B1",
    "US20030091347A1",
    "US20030033825A1",
    "US20030051486A1",
    "US20030086338A1",
    "US20030089493A1",
    "US20030221726A1",
    "US20040104654A1",
    "US20050279119A1",
    "US20050126630A1",
    "US20050178285A1",
    "US20050241333A1",
    "US20060202042A1",
    "US20080276540A1",
    "US20070157645A1",
    "US20090273265A1",
    "US10188098B2",
    "US20130247605A1",
    "US20150137674A1",
    "US20150343881A1",
    "US20160356517A1",
    "US20180311659A1"
  ]
}