# US 11,444,509 B2 · Air-cooling system for portable generator > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,444,509 B2 - Document ID: US11444509B2 - Status: Granted - Kind: B2 - Application number: 17/126,927 - Filed: 2020-12-18 - Published: 2022-06-23 - Granted: 2022-09-13 - Earliest claimed: 2020-12-18 - Assignees: NPS Corporation - Applicants: N.P.S. Company, LLC - Inventors: Junjie Dai; Jinbao Chen - Web page: https://patentgrep.com/patent/US11444509B2 ## CPC - H02K 5/207: {with openings in the casing specially adapted for ambient air} - F02B 63/042: {Rotating electric generators} - F02B 63/044: {the engine-generator unit being placed on a frame or in an housing} - F02B 63/048: {Portable engine-generator combinations} - H02K 7/1815: {structurally associated with reciprocating piston engines (general aspects of generating sets, e.g. housing, F02B63/04)} - H02K 9/04: having means for generating a flow of cooling medium - H02K 11/33: Drive circuits, e.g. power electronics (H02K11/38 takes precedence) - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - F02B: INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL (gas-turbine plants F02C; hot-gas or combustion-product positive-displacement engine plants F02G) ## Abstract Devices, systems, and methods to air cool a portable generator are disclosed. The devices include various air ducts to direct airflow over heated components within a cabinet of the portable generator to cool the components by convection. A damping fan draws ambient temperature air into the cabinet and directs the air into channels of an outflow duct. ## Claims ### Claim 1 A portable generator unit, comprising: a combustion engine; an alternator coupled to the combustion engine; a cabinet comprising a chassis; and an air-cooling system comprising: an air outflow duct disposed around the alternator and configured to guide an airflow away from the alternator; an engine airflow duct disposed adjacent the combustion engine and configured to guide the airflow toward the air outflow duct; a damping cooling fan coupled to the combustion engine and configured to draw ambient temperature air through the engine airflow duct and push heated air through the air outflow duct to cool the combustion engine; a first air inlet disposed in the chassis and configured to permit a first airflow of ambient temperature air into the cabinet; a second air inlet disposed in the chassis and configured to permit a second airflow of ambient temperature air into the cabinet and to guide the second airflow toward a cylinder block of the combustion engine; an electrical inverter disposed within the cabinet; and an inverter airflow duct disposed around the electrical inverter and configured to guide the first airflow from the first air inlet, over the electrical inverter, and toward a cylinder head of the combustion engine, wherein the inverter airflow duct comprises: a vertical portion disposed over the first air inlet; and a cylindrical portion in fluid communication with the vertical portion and configured to guide the first airflow toward a cylinder head of the combustion engine. ### Claim 2 (depends on 1) The portable generator unit of claim 1, wherein the air outflow duct comprises: a first airflow passage configured to receive the first airflow from the cylinder head of the combustion engine; a second airflow passage configured to receive the second airflow from the cylinder block; an airflow distributor configured to maintain separation of the first and second airflows within the air outflow duct; a first airflow outlet in communication with the first airflow passage; and a second airflow outlet in communication with the second airflow passage. ### Claim 3 (depends on 1) The portable generator unit of claim 1, wherein the engine air flow duct comprises: a first panel; a second panel; and a third panel; wherein the first panel, the second panel, and the third panel are coupled and at least partially surround the combustion engine. ### Claim 4 (depends on 1) The portable generator unit of claim 1, wherein the air-cooling system further comprises an insulation ring disposed between the alternator and the air outflow duct, wherein the insulation ring is configured to guide the airflow toward the air outflow duct. ### Claim 5 (depends on 1) The portable generator unit of claim 1, wherein the damping cooling fan comprises: a damping portion; a plurality of fan blades extending radially outward from the damping portion; a choke ring disposed at a perimeter of the plurality of fan blades; and a fan blade airflow passage defined by adjacent fan blades of the plurality of fan blades, the damping portion, and the choke ring. ### Claim 6 (depends on 1) The portable generator unit of claim 1, further comprising a connecting flange configured to couple an alternator stator with the combustion engine, wherein the connecting flange comprises a plurality of airflow passages. ### Claim 7 (depends on 1) The portable generator unit of claim 1, further comprising a control module, wherein the control module is configured to control any one of a key fob remote control system, an electric control system, an auto choke system, a fuel supply system, a battery charging system, and any combination thereof. ### Claim 8 A portable generator unit, comprising: a combustion engine; an alternator coupled to the combustion engine; a cabinet comprising a chassis; an air-cooling system comprising: an air outflow duct disposed around the alternator and configured to guide an airflow away from the alternator; an engine airflow duct disposed adjacent the combustion engine and configured to guide the airflow toward the air outflow duct; a damping cooling fan coupled to the combustion engine and configured to draw ambient temperature air through the engine airflow duct and push heated air through the air outflow duct to cool the combustion engine; a first air inlet disposed in the chassis and configured to permit a first airflow of ambient temperature air into the cabinet; a second air inlet disposed in the chassis and configured to permit a second airflow of ambient temperature air into the cabinet and to guide the second airflow toward a cylinder block of the combustion engine; an electrical inverter disposed within the cabinet; and an inverter airflow duct disposed around the electrical inverter and configured to guide the first airflow from the first air inlet, over the electrical inverter, and toward a cylinder head of the combustion engine, wherein the air outflow duct comprises: a first airflow passage configured to receive the first airflow from the cylinder head of the combustion engine, a second airflow passage configured to receive the second airflow from the cylinder block, an airflow distributor configured to maintain separation of the first and second airflows within the air outflow duct, a first airflow outlet in communication with the first airflow passage, and a second airflow outlet in communication with the second airflow passage. ### Claim 9 (depends on 8) The portable generator unit of claim 8, wherein the engine airflow duct comprises: a first panel; a second panel; and a third panel, wherein the first panel, the second panel, and the third panel are coupled and at least partially surround the combustion engine. ### Claim 10 (depends on 8) The portable generator unit of claim 8, wherein the air-cooling system further comprises an insulation ring disposed between the alternator and the air outflow duct, wherein the insulation ring is configured to guide the airflow toward the air outflow duct. ### Claim 11 (depends on 8) The portable generator unit of claim 8, wherein the damping cooling fan comprises: a damping portion; a plurality of fan blades extending radially outward from the damping portion; a choke ring disposed at a perimeter of the plurality of fan blades; and a fan blade airflow passage defined by adjacent fan blades of the plurality of fan blades, the damping portion, and the choke ring. ### Claim 12 (depends on 8) The portable generator unit of claim 8, further comprising a connecting flange configured to couple an alternator stator with the combustion engine, wherein the connecting flange comprises a plurality of airflow passages. ### Claim 13 (depends on 8) The portable generator unit of claim 8, further comprising a control module, wherein the control module is configured to control any one of a key fob remote control system, an electric control system, an auto choke system, a fuel supply system, a battery charging system, and any combination thereof.