Title of Invention

A DUCT STRUCTURE FOR AN AIR - CONDITIONED VEHICLE

Abstract

Rear AC roof air duct has a branched configuration and is part of the headliner to distribute conditioned air in the passenger cabin. Air vent outlets emit conditioned air from the air duct towards the respective rear seats in SUV type of vehicle. Rear AC unit located at right extreme corner of the vehicle provides conditioned air to the ducts located in ceiling structure through off take duct. The third row air vents are placed closer so that common design is used for both front-facing and side-facing third row passenger seat arrangement. The roof duct is designed around the volume the air flow would naturally occupy after entering into the roof duct. Roof duct design and baffle geometry helped in minimizing pressure drop and getting flow balance in each branch.

Full Text

FORM 2 THE PATENTS ACT 1970 (39 of 1970) & THE PATENTS RULES, 2003 COMPLETE SPECIFICATION (See Section 10; rule 13) TITLE OF THE INVENTION A DUCT STRUCTURE INTEGRATED INTO HEADLINER FOR AIR-CONDITIONED VEHICLE APPLICANTS TATA MOTORS LIMITED, an Indian company having its registered office at Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai 400 001 Maharashtra, India INVENTORS Lee Gale, a National of United Kingdom of TATA Motors European Technical Centre PLC, 3 rd floor International Automotive Research Centre, University of Warwick Coventry CV4 74L UK and Sachin Shendge, an Indian national of TATA Motors LIMITED an Indian company having its registered office at Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai 400 001 Maharashtra, India PREAMBLE TO THE DESCRIPTION The following Complete specification particularly describes the invention and the manner in which it is to be performed. FIELD OF INVENTION The present invention relates to improved distribution of conditioned air through air vent outlets onto respective rear seats in a passenger compartment of the SUV type of vehicle. The present invention also relates to an improved roof air duct which maintains desired quantity and direction of conditioned air through air vent outlets. The present invention also relates to an improved air distribution duct (via several separate air passageways) mounted between headliner (ceiling base member) and the metallic roof of the vehicle. This invention is a common design for front facing and side facing third row passengers in SUV. BACKGROUND OF INVENTION The conventionally known roof air duct is meant for improved distribution of conditioned air in the rear passenger compartment of the vehicle. Forked type branched configuration is commonly used to deliver conditioned air through several separate air passageways. Conventionally four air emitting ports are used, two for second row and two for third row of passenger compartment. First row of passenger cabin is taken care by dashboard air vent outlets. In some SUVs, an auxiliary AC unit is located between driver and co-driver seats for cooling second row of passenger compartment. And third row of cabin is conditioned by roof mounted unit which is not concealed in the ceiling structure. In the conventional air distributing ducts, there is possibility that a greater volume of air, introduced in the roof duct tends to be directed towards the air passageway located close to the main airflow route of the inlet portion of roof 2 duct. This may lead to uneven distribution of conditioned air in the passenger compartment. Figure 1 shows the conventional air duct with branched configuration. In the air duct of Fig. 1, the air supplied from the air conditioning unit to the air inlet portion 101 is directed to the extended air passageway 105, located close to the direction of the extension line or main airflow route of the inlet portion 101, in a much greater volume than directed to the extended air passageway 102 greatly deviated from the main airflow route of the inlet 101. The extended air passageways are deviated about 90 degree from the main air flow route that will cause additional pressure drops and turbulences. The extended air passageway 102 is relatively close to the main airflow route of the inlet portion 101; it tends to impart a greater resistance to the flowing conditioned air due to its great length and thereby considerably restricts the volume of the conditioned air flowing there through. The remaining extended air passageway 103 is also greatly deviated from the main airflow route of the inlet portion 101 and has a great length, so that the volume of the conditioned air flowing through the air passageway 112 is also considerably restricted. In this conventional roof air duct constructed into a branched configuration, the conditioned air is emitted through the air emission port 109 in a greater volume than emitted through the other air emission ports 106, 107 and 108, thereby resulting in a non uniform conditioned-air distribution within the vehicle compartment. Figure 2 shows another concept used in air conditioning roof duct according to US6616523, wherein the conditioned air is accumulated in a chamber and distributed through vents. Air inlet duct is located near corner of the accumulating chamber and there are chances that the air vents located near inlet area may have higher distribution of air compared to air vents located in the front portion of the chamber. 3 OBJECTIVES OF INVENTION The main object of this invention is to accommodate separate air passageways for each air vent outlet inside the ceiling structure. Yet another object of this invention is to evenly distribute desired air quantity through each air passageway and air vent outlet. SUMMARY OF INVENTION The above objectives are achieved by providing an air duct on a ceiling of a vehicle comprising, an air inlet portion for introducing air into said air duct, a main airflow route, plurality of air passageways extended from the said main airflow route, said main airflow route distributing the air to be delivered from said air inlet portion to said air passageways, wherein walls joining between said air passageways extended into said main airflow route such that inlet portions of said air passageways located in main air flow route and stream lined with said air inlet portion of the air duct. In another embodiment of this invention an air duct provided on a ceiling of a vehicle comprising, an air inlet portion for introducing air into said air duct, a main airflow route having plurality of projections for accommodating air vents, plurality of air passageways extended from said main airflow route, said main airflow route distributing the air to be delivered from said air inlet portion to said air passageways, plurality of baffles located in main air flow route to divert the air from the main air flow route to said air passageways and to said air vents located in projections provided on said main airflow route. In another embodiment of this invention, an air duct is provided on a ceiling of a vehicle comprising, an air inlet portion for introducing air into said air duct, plurality of air vents provided underside of said air duct for emitting the air 4 from said air duct towards respective rear seats of the vehicle, said rear seats located in second and third row passenger compartments of said vehicle wherein distance between the air vents for emitting the air from said air duct towards rear seats located in third row passenger compartment closer than the distance between the air vents for emitting the air from said air duct towards rear seats located in second row passenger compartment. In another embodiment of this invention, an air duct is provided on a ceiling of a vehicle comprising, an air inlet portion for introducing air into said air duct, a main airflow route, two air passageways connected to main airflow route and extended to front passenger compartment of the vehicle, two air passageways connected to main airflow route and extended to rear passenger compartment of said vehicle, said main airflow route distributing the air to be delivered from said air inlet portion to said air passageways, wherein said air passageways extended to rear passenger compartment of the vehicle located inner of the said air passageways extended to front passenger compartment of the vehicle. BRIEF DESCRIPTION OF DRAWINGS The present invention can be described better in greater details with the drawings. Fig. 1 shows the branched configuration of conventional air duct. Fig. 2 shows the accumulated air chamber arrangement as per the prior art. Fig. 3 is an overall perspective view of an automotive roof duct in accordance with this invention. Fig. 4 is view of roof duct with air outlet vent location. Fig. 5 is outline of the roof duct according to present invention. Fig. 5a is outline of roof duct with baffle arrangement. Fig. 6 is a sectional view taken along the line A-A of FIG. 4 Fig. 7a & 7b shows the air vent arrangement according to present invention. 5 DETAILED DESCRIPTION OF INVENTION Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting the same, FIG. 3 is an overall perspective of a roof duct with air conditioning unit accordance with the present invention. It represents main air flow route (2) with four different branches for each air vent outlet. Side branches (3, 4) leading to the second row and inner branches (5, 6) leading to third row passenger compartments. The roof duct is connected to rear AC, "8" (located at extreme rear right corner) by off take duct (7) which passes through the D-pillar of the SUV. The air conditioning unit contains heater unit, a cooler unit and a blower motor. It also includes roof duct provided under the roof panel and connected to the air conditioning unit through off take duct. Depressions are provided on the roof duct for accommodating roof bow or any other packing constrains. FIG. 4 shows the location of air vent outlets for second and third row passenger compartment. Four separate air passageways are provided for each air vent outlet. The roof duct is divided into four passageways from the main airflow route of roof duct. The air vent outlets for third row of passenger compartment are closer than second row air vent outlets. This is to accommodate for both front facing and side facing third row seat arrangement. This is to follow the guidelines of minimum distance between air vent outlet and passenger nose. This type of arrangement makes sure that every one of the passengers on these seats can easily reach and manipulate the nearest air vent to direct air towards them. Thus, the present invention can enhance the convenience of use or operability of the air vent outlets to get air diverted to desired direction. 6 The third row air outlet vents (air emission ports) "10a, 10b" are closer than second row air outlet vents (9a, 9b). The third row seat can be front-facing or side-facing according to the arrangement of seats. The seating position can be changed by changing the seating configuration from front-facing to side-facing. In the Present invention air emission ports are located in such a way that the emission ports (10a, 10b) in third row suited for both front-facing and side-facing configuration of the third row. This gives an added advantage for the passenger in the third row for getting substantially even distribution of air in both seating configurations. The air vent can be rotate and adjusted to suite both the seating configurations so that the conditioned air flows directly to the passenger seated in the third row. Air vents for emitting the air from air duct towards rear seats located in third row passenger compartment is at least 300mm from nose level of passenger seated in front-facing and side-facing configuration of said rear seat. The passenger height has been decided according to the standard SAE (society of Automotive Engineers) manikin (specified height 1.89m). Manikin used is 95% of above standard manikin. FIG. 5 indicates roof duct configuration according to present invention. The roof duct is having branched configuration with a main air flow route(2) connecting directly to the off take duct with and air inlet portion (1) located at the top of rear pillar of the vehicle and four extended air flow passages (3,4,5,6) connect to the main air flow route (2) leading to the second and third row passenger compartment. The main air flow route (2) is configured in width wise direction of the vehicle in the rear. The main air flow route connected to off take duct located at the top of the rear pillar of the vehicle. First extended air passageway (3) starting from the inlet portion of main air flow route (2) and leading towards the second row passenger compartment. The inlet portion of second extended air passageway (4) is located at end of the main air flow route (2) and leading towards the second row passenger compartment. Both the extend passageways are running in the longitudinal direction of the vehicle body and taking the air from the main air flow root of the roof duct to the 7 second row passenger compartment of the vehicle. The above two extended air flow passageways (3, 4) form side branches of branched configuration of the air duct. The main air flow route (2) of the air duct further provided with two inner extended passageways (5, 6) located between first and second extended air passageway (3, 4). These inner extended passageways lead the air from the main air flow route (2) to the third row passenger compartment and formed as inner branches of branched configuration of the air duct. The inlet portions of extended passageways are located in the main air flow route and configured to give a substantially efficient and even distribution of conditioned air in both first and second row compartments. The second extended air passageway (4) is having greater length compared to other air passageways and imparts a greater resistance to the flowing conditioned air due to its great length. To overcome the resistance effect in second extended passageway (4) the inlet portion of the passageway is located in main air flow route (2) and the wall (13) joining with the inner extended air passageway (6) is configured and extended to inner portion of the main air flow route (2). This leads greater volume of air to the second extended air passageway (4). The first extended air passageway (3) is having inlet portion near the inlet portion (1) of the main air flow route and the wall (11) joining with the inner air passageway (5) configured in such way that sufficient quantity of air diverted to this passageway(3) to overcome resistance due to higher length. Again the wall (12) between inlet portions of two inner passageways configured and extended into main air flow route to divide the air flow equally between two inner air passageways (5,6). The walls (11, 12, and 13) between the air passageways are configured in such way that the inlet portions of extended air passageways are extended into the main airflow route and stream lined with inlet portions of the main air flow route. The configuration of air passageways are decided after studying the air flow pattern while air enters the roof duct. Branch division is finalized so that air flows naturally through the different branches (air passageways) as per volume flow 8 requirement. Air flow is not forced to change the route or direction to achieve the target. Referring to Fig.5a, the above configuration can also be achieved by providing a roof duct with a main air flow route (2) and two extended air passageway at both ends. The main air flow route (2) further is having two projections (5', 6') to configure the inner extended air passageways (5, 6). Air vents are located at the projections (5', 6') in main air flow route and baffles (11a, 12a, 13a) are used to create the air passageways in projections areas (5', 6'). Three baffles (11a, 12a, 13a) are provided to divert the air from the main air flow route (2) to the side extended passageways (3, 4) and inner air passageways (5, 6). First baffle (11a) located at the inlet portion of main air flow route. This baffle controls the air flow to the first extend air passageway (3) leading to the second row passenger compartment. Second baffle (12a) is provided at the middle portion of the main air flow route. The first (11a) and second baffle (12a) form a passageway for flow of air from the main air flow route (2) to the first inner air passageway (5). The third baffle (13a) is located at the end portion of the main air flow route (2) where it form a path with the second baffle (12a) to lead the air to the second inner air passageway (6). Both the inner air passageways (5,6) having air emission port (air vents) at their end to emit the air to the third row passenger compartment. The third baffle (13a) also helps to control the air flow from the main branch to the second extended air passageway leading to the second passenger compartment. Third baffle (13a) extended into the main airflow route to divert more conditioned air to the second extend air passageway(4) and also form air flow path for inner extended air passageway. An air distribution member (14) is provided at the inlet portion of the main air flow route to get even distribution in the inner extended passageways. Air vents (air emission ports) are located at end of the each passageway and fixed to the underside of the same. Conventional roof duct have extended air passageways which deviated from the main air flow route and this results in uneven distribution of conditioned air 9 in second and third passenger compartments. In contrast present invention roof duct having inlet portions of all extended air passageways stream lined with the main flow route or inlet portion of the main air flow route. Further the end of walls joining between the extend air passageways are configured to direct greater volume of air into passageways having greater length and this result in substantially even distribution of the conditioned air in all two and three compartment. Air is supplied from air conditioning unit to air inlet portion (1) is directed to extended passageways (3,4,5,6) and distributed substantially even through the vents in second and third compartments. The extended passageways are deviated from the main flow route (2) and to over come the resistance due this profile the inlet portions of the extended passageways are extended into the main air flow route and also the profile of the inlet portions are configured in such way that inlet portion of extended passageways are stream lined with the main inlet portion (1). The baffles (11a, 12a, 13a) configured and arranged to carry sufficient volume of air to have a substantially even distribution through all air vents. Arrows a, b, c & d shows the air flow from the main inlet portion to the extended passageways. Reference to Fig. 6, the roof duct having inverted open channel cross section (21) glued on the head liner (20) which then connected to the metallic roof of the vehicle. Depressions are provided on the roof duct for accommodating roof bow or any other packing constrains. Reference to Fig. 7a and 7b, figure 7a is an exploded perspective view showing the air vent, '30' (air emitting direction adjustment grille) and hole (31) for mounting the air emitting direction adjustment grille in the vehicle headliner. The air emitting direction adjustment grille rotatably mounted in the mounting hole (31). The grille has an outer circular member with flanges at bottom (33) and locking flanges (34) located opposite to each other at the top. The grille is inserted into the mounting hole (31) in the head liner. The mounting hole having a diameter less than diameter of flanges (33) of outer circular member and two enlarged curved opening (31') for inserting the locking flanges (34). 10 After inserting the grille, it is turned and locked in position. An inner circular member (35) rotatably mounted on the outer member which can be rotated in 360degree. The grille further includes a plurality of parallel fins (32) each pivotably held by an inner circular member. The fins are acting together with the help of connecting member (36) located above the fins. Parallel air silts or elongated air gaps are formed between the fins for volume and direction -controlled emission of conditioned air. The inner circular member along with fins can be rotated 360 degree so that the fins can adjusted for both front-facing and side-facing configuration of the seating position. The air duct, designed around the volume of the air flow would naturally occupy, helps in minimizing pressure losses due to recirculation, restrictions, flow diversions, etc. The baffles are so located that they do not force air flow to change or divert air flow direction which may cause pressure losses. These baffles only guide the air flow towards the desired directions. The cross-sectional areas are made consistence through each long branch so that flow restrictions are even. Two short depressions, due to roof bow inclusion, are reduced to one long depression to avoid the repeated contraction-expansion of the air which in turn helps to reduce pressure losses. The areas around three vent outlets are modified to get desired direction of air flow inside the cabin. This avoided swirling of air around the vent. The foregoing description is a specific embodiment of the present invention. It should be appreciated that this embodiment is described for purpose of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof. 11 WE CLAIM 1. An air duct provided on a ceiling of a vehicle comprising, an air inlet portion for introducing air into said air duct, a main airflow route, plurality of air passageways extended from the said main airflow route, said main airflow route distributing the air to be delivered from said air inlet portion to said air passageways, wherein walls joining between said air passageways extended to said main airflow route such that inlet portions of said air passageways located in main air flow route and stream lined with said air inlet portion of the air duct. 2. An air duct provided on a ceiling of a vehicle as claimed in claim 1, wherein two air passageways extended to distribute the air from main airflow route to the second row passenger compartment of the vehicle and two air passageways extended to distribute the air from main airflow route to the third row passenger compartment of the vehicle. 3. An air duct provided on a ceiling of a vehicle as claimed in claim 1, wherein air passageways extended to distribute the air from said main airflow route to third row passenger compartment of the vehicle is located inner of air passageways extended to distribute the air from said main airflow route to second row passenger compartment of the vehicle. 4. An air duct provided on a ceiling of a vehicle as claimed in claim 1, wherein the wall joining between the inner air passageway and the outer air passageway located at the end of said main airflow route is extend to said main air flow route for diverting greater volume of air from said main airflow route to said outer air passageway. 5. An air duct provided on a ceiling of a vehicle as claimed in claim 1, wherein the wall joining between the inner air passageway and the outer 12 air passageway located at the inlet portion of said main airflow route is extend to said main air flow route for diverting air from said main airflow route to said outer air passageway. 6. An air duct provided on a ceiling of a vehicle as claimed in claim 1, wherein the wall joining between the inner air passageways located at the middle portion of said main airflow route is extend to main air flow route for substantially even distribution of air from said main airflow route to said inner air passageways. 7. An air duct provided on a ceiling of a vehicle comprising, an air inlet portion for introducing air into said air duct, a main airflow route having plurality of projections for accommodating air vents, plurality of air passageways extended from said main airflow route, said main airflow route distributing the air to be delivered from said air inlet portion to said air passageways, plurality of baffles located in main air flow route to divert the air from the main air flow route to said air passageways and to said air vents located in projections provided on said main airflow route. 8. An air duct provided on a ceiling of a vehicle as claimed in claim 7, wherein baffles are located at inlet portion, middle portion and end portion of said main airflow route. 9. An air duct provided on a ceiling of a vehicle as claimed in claim 7, wherein baffles are configured and extended to said main airflow route for substantially even distribution of air through all air vents. 10. An air duct provided on a ceiling of a vehicle as claimed in claim 7, wherein said main airflow route having two projections and said 13 projections located above third row passenger compartment of said vehicle. 11. An air duct provided on a ceiling of a vehicle as claimed in either claim 1 or claim 7, wherein an air distribution member is located in said main airflow route for distributing the air substantially even in inner air passageways. 12. An air duct provided on a ceiling of a vehicle as claimed in any one of the preceding claims wherein air vents provided underside of said air passageways and located at end portion of said air passageways. 13. An air duct provided on a ceiling of a vehicle as claimed in any one of the preceding claims wherein said air duct having an inverted open channel cross sectional shape, glued to top of the headliner of said vehicle and said headliner connected to roof panel of the said vehicle. 14. An air duct provided on a ceiling of a vehicle comprising, an air inlet portion for introducing air into said air duct, plurality of air vents provided underside of said air duct for emitting the air from said air duct towards respective rear seats of the vehicle, said rear seats located in second and third row passenger compartments of said vehicle wherein distance between the air vents for emitting the air from said air duct towards rear seats located in third row passenger compartment closer than the distance between the air vents for emitting the air from said air duct towards rear seats located in second row passenger compartment. 15. An air duct provided on a ceiling of a vehicle as claimed in claim 14, wherein said air vents for emitting the air from said air duct towards rear seats located in third row passenger compartment is common to front-facing and side-facing configuration of said rear seat. 14 16. An air duct provided on a ceiling of a vehicle as claimed in claim 14, wherein said air vents for emitting the air from said air duct towards rear seats located in third row passenger compartment is at least 300mm from nose level of passenger seated in front-facing and side-facing configuration of said rear seat. 17. An air duct provided on a ceiling of a vehicle comprising, an air inlet portion for introducing air into said air duct, a main airflow route, two air passageways connected to main airflow route and extended to front passenger compartment of the vehicle, two air passageways connected to main airflow route and extended to rear passenger compartment of said vehicle, said main airflow route distributing the air to be delivered from said air inlet portion to said air passageways, wherein said air passageways extended to rear passenger compartment of the vehicle located inner of the said air passageways extended to front passenger compartment of the vehicle. 18. An air duct provided on a ceiling of a vehicle as claimed in claim 17, wherein inlet portions of said air passageways are located in said main airflow route and steam lined with inlet portion said air duct. 19. An air duct provided on a ceiling of a vehicle substantially as herein described with reference to accompanying drawings. 15 ABSTRACT A DUCT STRUCTURE INTEGRATED INTO HEADLINER FOR AIR-CONDITIONED VEHICLE Rear AC roof air duct has a branched configuration and is part of the headliner to distribute conditioned air in the passenger cabin. Air vent outlets emit conditioned air from the air duct towards the respective rear seats in SUV type of vehicle. Rear AC unit located at right extreme corner of the vehicle provides conditioned air to the ducts located in ceiling structure through off take duct. The third row air vents are placed closer so that common design is used for both front-facing and side-facing third row passenger seat arrangement. The roof duct is designed around the volume the air flow would naturally occupy after entering into the roof duct. Roof duct design and baffle geometry helped in minimizing pressure drop and getting flow balance in each branch. Fig 3

Documents:

2308-MUM-2007-ABSTRACT(18-1-2012).pdf

2308-mum-2007-abstract.doc

2308-mum-2007-abstract.pdf

2308-MUM-2007-CLAIMS(AMENDED)-(18-1-2012).pdf

2308-MUM-2007-CLAIMS(AMENDED)-(21-3-2013).pdf

2308-MUM-2007-CLAIMS(AMENDED)-(28-8-2014).pdf

2308-MUM-2007-CLAIMS(AMENDED)-(29-9-2014).pdf

2308-MUM-2007-CLAIMS(MARKED COPY)-(28-8-2014).pdf

2308-MUM-2007-CLAIMS(MARKED COPY)-(29-9-2014).pdf

2308-mum-2007-claims.doc

2308-mum-2007-claims.pdf

2308-MUM-2007-CORRESPONDENCE(13-12-2007).pdf

2308-MUM-2007-CORRESPONDENCE(21-6-2013).pdf

2308-mum-2007-correspondence-received.pdf

2308-mum-2007-description (complete).pdf

2308-mum-2007-drawings.pdf

2308-MUM-2007-FORM 1(13-12-2007).pdf

2308-MUM-2007-FORM 1(18-1-2012).pdf

2308-MUM-2007-FORM 13(18-1-2012).pdf

2308-MUM-2007-FORM 13(21-3-2013).pdf

2308-MUM-2007-FORM 18(10-12-2007).pdf

2308-MUM-2007-FORM 2(TITLE PAGE)-(18-1-2012).pdf

2308-MUM-2007-FORM 8(10-12-2007).pdf

2308-MUM-2007-FORM 9(10-12-2007).pdf

2308-mum-2007-form-1.pdf

2308-mum-2007-form-2.doc

2308-mum-2007-form-2.pdf

2308-mum-2007-form-26.pdf

2308-mum-2007-form-3.pdf

2308-MUM-2007-GENERAL POWER OF ATTORNEY(18-1-2012).pdf

2308-MUM-2007-MARKED COPY(18-1-2012).pdf

2308-MUM-2007-OTHER DOCUMENT(21-3-2013).pdf

2308-MUM-2007-REPLY TO EXAMINATION REPORT(18-1-2012).pdf

2308-MUM-2007-REPLY TO HEARING(21-3-2013).pdf

2308-MUM-2007-REPLY TO HEARING(28-8-2014).pdf

2308-MUM-2007-REPLY TO HEARING(29-9-2014).pdf

2308-MUM-2007-SPECIFICATION(AMENDED)-(18-1-2012).pdf

2308-MUM-2007-SPECIFICATION(AMENDED)-(21-3-2013).pdf

2308-MUM-2007-SPECIFICATION(MARKED COPY)-(21-3-2013).pdf

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