# US 2017/0282686 A1 · Demist control for hvac > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0282686 A1 - Document ID: US20170282686A1 - Status: Published application - Kind: A1 - Application number: 15/087,343 - Filed: 2016-03-31 - Published: 2017-10-05 - Earliest claimed: 2016-03-31 - Assignees: DENSO International America, Inc. - Applicants: DENSO International America, Inc. - Inventors: Christopher WISNIEWSKI - Web page: https://patentgrep.com/patent/US20170282686A1 ## CPC - B60H 1/00842: {the system comprising a plurality of damper doors; Air distribution between several outlets} - B60H 1/00564: {of air ducts} - B60H 1/00671: {Damper doors moved by rotation; Grilles} - B60H 2001/00092: {of air deflecting or air directing means inside the device} - B60H 2001/00714: {Details of seals of damper doors} - B60H 2001/00721: {Air deflecting or air directing means} - B60H: ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES ## Abstract An HVAC system including a defrost manifold. The defrost manifold has a first side window outlet, a second side window outlet, and a windshield outlet. A first rib partially obstructs the first side window outlet. A second rib partially obstructs the second side window outlet. A control door is movable to open and close the defrost manifold. A first wall extends from a first portion of the control door that is opposite to the first side window outlet. A second wall extends from a second portion of the control door that is opposite to the second side window outlet. Movement of the control door varies the position of the first wall relative to the first rib, and varies the position of the second wall relative to the second rib, to control airflow through the first and second side window outlets ## Claims ### Claim 1 A vehicle heating, ventilation, and air cooling (HVAC) system comprising: a defrost manifold including a first side window outlet, a second side window outlet, and a windshield outlet; a first rib partially obstructing the first side window outlet; a second rib partially obstructing the second side window outlet; a control door movable to open and close the defrost manifold; a first wall extending from a first portion of the control door that is opposite to the first side window outlet; and a second wall extending from a second portion of the control door that is opposite to the second side window outlet; wherein movement of the control door varies the position of the first wall relative to the first rib, and varies the position of the second wall relative to the second rib, to control airflow through the first and the second side window outlets. ### Claim 2 (depends on 1) The HVAC system of claim 1, wherein the defrost manifold is defined by an HVAC case including an evaporator and a heater core therein. ### Claim 3 (depends on 1) The HVAC system of claim 1, wherein the first rib and the second rib each extend generally perpendicular to a direction of airflow passing through the defrost manifold. ### Claim 4 (depends on 1) The HVAC system of claim 1, wherein: the control door is a single control door including an elongated panel extending across an entirety of the defrost manifold; and the first wall and the second wall each extend from the elongated panel. ### Claim 5 (depends on 4) The HVAC system of claim 4, wherein the first wall and the second wall each extend perpendicular to the elongated panel. ### Claim 6 (depends on 4) The HVAC system of claim 4, wherein at least one of the first wall and the second wall is curved towards the first rib or the second rib respectively. ### Claim 7 (depends on 1) The HVAC system of claim 1, wherein the windshield outlet is between the first side window outlet and the second side window outlet. ### Claim 8 (depends on 1) The HVAC system of claim 1, wherein: the control door is positionable in at least a closed position, an open position, and an intermediate position; in the closed position an elongated panel of the control door extends generally parallel to each one of the first rib and the second rib, and prevents airflow from passing through the defrost manifold; in the open position the control door is rotated from the closed position to define first airflow clearances between the elongated panel and each of the first and second ribs, and second airflow clearances between each of the first and second walls and the first and second ribs respectively; in the intermediate position the control door is rotated to a position between the closed position and the open position such that the first airflow clearances in the intermediate position are both smaller than the first airflow clearances in the open position, and the second airflow clearances in the intermediate position are both smaller than the second airflow clearances in the open position; and airflow having been heated by the heater core and flowing out through the first and second side window outlets is metered by rotating the control door to vary sizing of the first and second airflow clearances. ### Claim 9 (depends on 1) The HVAC system of claim 1, wherein the control door is a flag door. ### Claim 10 A vehicle heating, ventilation, and air cooling (HVAC) system comprising: a casing including an evaporator and a heater core; a first side window demist outlet defined by the casing; a first rib of the casing extending partially across the first side window demist outlet to partially obstruct airflow through the first side window demist outlet; a second side window demist outlet defined by the casing; a second rib of the casing extending partially across the second side window demist outlet to partially obstruct airflow through the second side window demist outlet; a windshield defrost outlet defined by the casing; a control door mounted within the casing and movable to open and close each one of the first side window demist outlet, the second side window demist outlet, and the windshield defrost outlet; a first wall extending from a first portion of the control door that is opposite to the first side window demist outlet; and a second wall extending from a second portion of the control door that is opposite to the second side window demist outlet; wherein: movement of the control door varies position of the first wall relative to the first rib to control airflow through the first side window demist outlet; and movement of the control door varies position of the second wall relative to the second rib to control airflow through the second side window demist outlet. ### Claim 11 (depends on 10) The HVAC system of claim 10, wherein each one of the first rib and the second rib extends generally perpendicular to the direction of airflow through the defrost manifold. ### Claim 12 (depends on 10) The HVAC system of claim 10, wherein the windshield defrost outlet is between the first side window demist outlet and the second side window demist outlet. ### Claim 13 (depends on 10) The HVAC system of claim 10, wherein the control door is a flag door. ### Claim 14 (depends on 10) The HVAC system of claim 10, wherein the first wall and the second wall each extend from an elongated panel of the control door that extends across each one of the first side window demist outlet, the windshield defrost outlet, and the second side window demist outlet. ### Claim 15 (depends on 14) The HVAC system of claim 14, wherein the first wall and the second wall each extend perpendicular to the elongated panel. ### Claim 16 (depends on 14) The HVAC system of claim 14, wherein at least one of the first wall and the second wall is curved towards the first rib or the second rib respectively. ### Claim 17 (depends on 14) The HVAC system of claim 14, wherein at least one of the first wall and the second wall is curved away from the first rib or the second rib respectively. ### Claim 18 (depends on 10) The HVAC system of claim 10, wherein: the control door is positionable in at least a closed position, an open position, and an intermediate position; in the closed position an elongated panel of the control door extends generally parallel to each one of the first rib and the second rib, and a flexible seal of the control door contacts the case, to prevent airflow from passing through the defrost manifold; in the open position the control door is rotated from the closed position to define first clearances between the elongated panel and each of the first and second ribs, and second clearances between each of the first and second walls and the first and second ribs respectively; in the intermediate position the control door is rotated to a position between the closed position and the open position such that the first clearances in the intermediate position are both smaller than the first clearances in the open position, and the second clearances in the intermediate position are both smaller than the second clearances in the open position; and airflow having been heated by the heater core and flowing out through the first and second side window outlets is metered by rotating the control door to vary sizing of the first and second clearances. ### Claim 19 (depends on 10) The HVAC assembly of claim 10, further comprising a flexible seal extending around at least a distal portion of an elongated panel of the control door, the flexible seal contacting the case when the control door is in a closed position to prevent airflow through the first side window demist outlet, the second side window demist outlet, and the windshield defrost outlet. ### Claim 20 (depends on 10) The HVAC assembly of claim 10, further comprising a defrost manifold of the casing, the defrost manifold including each one of the first side window demist outlet, the second side window demist outlet, and the windshield defrost outlet.