# US 10,945,429 B2 · Extremely fast freezing, low-temperature blast freezer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,945,429 B2 - Document ID: US10945429B2 - Status: Granted - Kind: B2 - Application number: 16/852,301 - Filed: 2020-04-17 - Published: 2020-09-17 - Granted: 2021-03-16 - Earliest claimed: 2009-05-12 - Assignees: Reflect Scientific Inc. - Applicants: William G. Moon; William J. Hancock; Steven V. Boyce; Steven J. Parkinson - Inventors: William G. Moon; William J. Hancock; Steven V. Boyce; Steven J. Parkinson - Web page: https://patentgrep.com/patent/US10945429B2 ## CPC - A01N 1/145: Stationary or portable vessels generating cryogenic temperatures, e.g. liquid nitrogen baths - F25D 3/102: {Stationary cabinets} - F25D 17/06: by forced circulation - F25D 29/001: {for cryogenic fluid systems} - F25D 29/006: {Safety devices} - F25D 2700/122: of freezer compartments - A01N: PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF (preservation of food or foodstuff A23); BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES (preparations for medical, dental or toiletry purposes which kill or prevent the growth or proliferation of unwanted organisms A61K); PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS - F25D: REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR (refrigerated showcases A47F3/04; thermally-insulated vessels for domestic use A47J41/00; refrigerated vehicles, see the appropriate subclasses of classes B60 - B64; containers with thermal insulation in general B65D81/38; heat-transfer, heat-exchange or heat-storage materials, e.g. refrigerants, or materials for the production of heat or cold by chemical reactions other than by combustion C09K5/00; thermally-insulated vessels for liquefied or solidified gases F17C; air-conditioning or air-humidification F24F; refrigeration machines, plants, or systems F25B; cooling of instruments or comparable apparatus without refrigeration G12B) ## 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 ### Claim 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, 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; 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. ### Claim 2 (depends on 1) The system of claim 1, comprising one or more vent holes placed at predetermined locations on the payload bay. ### Claim 3 (depends on 1) The system of claim 1, comprising a separate compartment located between the payload bay and the outside environment. ### Claim 4 (depends on 1) The system of claim 1, comprising a controller coupled to a thermocouple inside the payload bay. ### Claim 5 (depends on 4) The system of claim 4, wherein the controller performs proportional-integral-derivative (PID) control to maintain a set point within a predetermined limit. ### Claim 6 (depends on 1) The system of claim 1, wherein the one or more cryogenic solenoid valves are located at an exhaust port. ### Claim 7 (depends on 1) The system of claim 1, comprising one or more heating tubes within the plurality of evaporators. ### Claim 8 (depends on 1) 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. ### Claim 9 (depends on 1) The system of claim 1, comprising a battery to provide backup power. ### Claim 10 (depends on 1) The system of claim 1, wherein a safety valve is connected to the multiplicity of coolant tubes. ### Claim 11 (depends on 10) The system of claim 10, wherein the safety valve has one or more heating fins or electrical heat tape coupled to it. ### Claim 12 (depends on 1) The system of claim 1, comprising one or more pneumatic latches. ### Claim 13 (depends on 12) The system of claim 12, wherein the one or more pneumatic latches and the pneumatic seal are powered by gaseous nitrogen. ### Claim 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; an inner door and a pneumatic seal providing an airtight seal between the main door and the payload bay; and one or more latches to secure a main door.