# US 2014/0190182 A1 · Magneto caloric heat pump with variable magnetization > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0190182 A1 - Document ID: US20140190182A1 - Status: Published application - Kind: A1 - Application number: 13/738,047 - Filed: 2013-01-10 - Published: 2014-07-10 - Earliest claimed: 2013-01-10 - Assignees: General Electric Company - Applicants: General Electric Company - Inventors: Michael Alexander Benedict - Web page: https://patentgrep.com/patent/US20140190182A1 ## CPC - F25B 21/00: Machines, plants or systems, using electric or magnetic effects - F25B 2321/0021: with a static fixed magnet - F25B 2321/0023: with modulation, influencing or enhancing an existing magnetic field - F25D 11/00: Self-contained movable devices, e.g. domestic refrigerators - Y02B 30/00: Energy efficient heating, ventilation or air conditioning [HVAC] - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS - 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) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract A heat pump system that uses variable magnetization to control the amount of MCM subjected to a magnetic field is provided. More particularly, the amount of MCM subjected to a magnetic field can be selected based on the amount of refrigeration needed. As such, the heat pump system can be adjusted based on e.g., changes in ambient conditions, and the energy used in operating such a heat pump system can be conserved so as to increase energy efficiency of the system. ## Claims ### Claim 1 A method of operating a magneto caloric device, comprising: providing magneto caloric material and a magnetic field; positioning the magneto caloric material into the magnetic field; removing the magneto caloric material from the magnetic field; and controlling the extent of cooling or heating of the magneto caloric material by adjusting the amount of the magneto caloric material subjected to the magneto caloric effect during said steps of positioning and removing. ### Claim 2 (depends on 1) The method of operating a magneto caloric device as in claim 1, wherein said controlling step comprises decreasing the amount of the magneto caloric material exposed to the magnetic field during said step of positioning. ### Claim 3 (depends on 1) The method of operating a magneto caloric device as in claim 1, wherein said controlling step comprises decreasing the size of the magnetic field in said step of positioning, removing, or both. ### Claim 4 (depends on 1) The method of operating a magneto caloric device as in claim 1, wherein the magnetic field is created by at least one magnet having a longitudinal axis that defines a longitudinal direction, and wherein said controlling step comprises moving the magnet, the magneto caloric material, or both, along the longitudinal direction so as to decrease the amount of the magneto caloric material subject to the magneto caloric effect during said steps of positioning and removing. ### Claim 5 (depends on 1) The method of operating a magneto caloric device as in claim 1, further comprising the steps of: providing a plurality of magnets to create the magnetic field, the magnets arranged in a first configuration; and wherein said controlling step comprises rearranging said plurality of magnets into a second configuration so as so as to decrease the amount of the magneto caloric material subject to the magneto caloric effect during said steps of positioning and removing. ### Claim 6 (depends on 1) The method of operating a magneto caloric device as in claim 1, wherein the magneto caloric material comprises a plurality of zones of magneto caloric material arranged sequentially along a longitudinal direction, wherein each zone comprises magneto caloric material having a different temperature range over which the magneto caloric effect occurs as compared to an adjacent zone. ### Claim 7 (depends on 6) The method of operating a magneto caloric device as in claim 6, wherein said controlling step comprises changing the number of zones of magneto caloric material exposed to the magnetic field. ### Claim 8 (depends on 6) The method of operating a magneto caloric device as in claim 6, wherein said controlling step comprises changing the number of zones of magneto caloric material exposed to the magnetic field based on the ambient temperature. ### Claim 9 (depends on 1) The method of operating a magneto caloric device as in claim 1, wherein said controlling step further comprises decreasing the amount of magneto caloric material subjected to the magneto caloric effect as an ambient temperature decreases. ### Claim 10 (depends on 1) The method of operating a magneto caloric device as in claim 1, wherein said controlling step further comprises: measuring the ambient temperature; and using the ambient temperature to determine the amount of the magneto caloric material subjected to the magneto caloric effect during said steps of positioning and removing. ### Claim 11 A heat pump system, comprising: a regenerator housing defining a circumferential direction and rotatable about an axial direction, the axial direction extending between a first end and a second end of the regenerator housing, the regenerator housing comprising a plurality of chambers with each chamber extending longitudinally along the axial direction between a pair of openings, the plurality of chambers arranged proximate to each other along the circumferential direction; a plurality of stages, each stage comprising magneto caloric material positioned within one of the plurality of chambers and extending along the axial direction; a pair of valves comprising a first valve attached to the first end of the regenerator housing and a second valve attached to the second end of the regenerator housing, the first valve and second valve each comprising a plurality of apertures spaced apart from each other along the circumferential direction with each aperture positioned adjacent to one of the pair of openings of one of the plurality of chambers; a magnetic element positioned proximate to the regenerator housing and extending along the axial direction, the magnetic element creating a magnetic field, the magnetic element positioned so that a subset of the plurality of stages are moved in and out of the magnetic field as the regenerator housing is rotated about the axial direction; a pair of seals comprising a first seal positioned adjacent to the first valve and a second seal adjacent to the second valve such that the regenerator housing and the pair of valves are rotatable relative to the pair of seals, the first seal and the second seal each comprising a pair of ports positioned in an opposing manner relative to each other and also positioned so that each port can selectively align with at least one of the pair of openings of the plurality of chambers as the regenerator housing is rotated about the axial direction; and an actuator configured for moving the magnetic element, the regenerator housing, or both along the axial direction so as to control the amount of magneto caloric material experiencing the magneto caloric effect as said regenerator housing is rotated about the axial direction. ### Claim 12 (depends on 11) The heat pump system of claim 11, wherein the regenerator housing defines a radial direction and further comprises a cavity positioned radially-inward of the plurality of chambers, wherein the magnetic element is positioned within the cavity of the regenerator housing. ### Claim 13 (depends on 12) The heat pump system of claim 12, wherein the magnetic element comprises a plurality of magnets arranged in the shape of an arc and configured to project a magnetic field substantially along a radially-outward direction. ### Claim 14 (depends on 13) The heat pump system of claim 13, wherein the arc formed by the plurality of magnets extends about the circumferential direction by an amount in the range of about 170 degrees to about 190 degrees. ### Claim 15 (depends on 14) The heat pump system of claim 14, wherein the plurality of magnets are arranged in a HalBach array. ### Claim 16 (depends on 11) The heat pump system of claim of claim 11, wherein the regenerator housing defines a radial direction and further comprises a cavity positioned radially-inward of the plurality of chambers, and wherein the magnetic element further comprising a first plurality of magnets positioned within the cavity and a second plurality of magnets positioned radially outward of the regenerator housing. ### Claim 17 (depends on 11) The heat pump system of claim of claim 11, wherein the pair of ports on each of the pair of seals are positioned about the circumferential direction within a range of about 170 degrees to about 190 degrees from each other. ### Claim 18 (depends on 11) The heat pump system of claim of claim 11, wherein each stage of the plurality of stages comprises a plurality of zones of magneto caloric material arranged sequentially along the axial direction, wherein each zone comprises magneto caloric material having a different temperature range over which a change in the magnetic moments of the magneto caloric material occurs as compared to an adjacent zone. ### Claim 19 (depends on 18) The heat pump system of claim of claim 18, wherein the plurality of zones are arranged along the axial direction so that the temperature range over which the change in the magnetic moments of magneto caloric material occurs increases sequentially from zone to zone along the axial direction. ### Claim 20 (depends on 11) The heat pump system of claim 11, further comprising a motor in mechanical communication with the regenerator housing and configured for rotating the regenerator housing about the axial direction.