Title of Invention

AIR CONDITIONING ROOF UNIT

Abstract This invention relates to the air conditioning roof unit wherein blower motors are coupled with blower scrolls and placed inside the upper and lower casings of the air conditioning roof unit. Behind the blower assembly an evaporator is fixed and one end of which is connected to the thermostatic expansion valve and another end is connected to the refrigerant pipeline. Behind the evaporator a filter is provided to remove the water droplets and dust which are part of cool and dehumidified air. Insulation is provided inside the said upper and lower casing of air conditioning roof unit in order to prevent the transfer of heat from inside of vehicle to air conditioning roof unit. Drain hoses are connected to the lowermost part of the lowercasing of the air conditioning roof unit from sides. A centre duct is connected to the said upper and lower casings and side ducts are routed from extreme ends of said centre duct and extended towards the front of the vehicle. Grills are provided on the said air conditioning roof unit at the outlet end, at the bottom end and at the end of the said ducts. Said air conditioning roof unit have a provision to mount it inside the vehicle at roof. Said roof unit is provided with a cover having insulation lining inside said cover.
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
Air Conditioning Roof Unit
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
Ranganath Kumar S V, Ilango Nagappan both Indian nationals 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
This invention is related to air conditioning system used in vehicles; more particularly to air conditioning roof unit with minimized ducting to provide comfort to the passengers inside the vehicle.
BACKGROUND OF INVENTION
U.S. Pat. No. 4,608,834 discloses an air-conditioning system for a motor vehicle having an air-conditioning unit on a vehicle roof. In this conventional system, an evaporator and a blower for forming a refrigerating cycle are arranged in an air-conditioning unit, an air suction opening for sucking in air from a passenger compartment as well as a blower opening for blowing out cooled air by the evaporator are formed at a bottom portion of the air-conditioning unit, and the bottom portion is inserted into a roof opening formed at the vehicle roof. According to such structure, the air suction opening as well as the blower opening are arranged at a ceiling of the passenger compartment, and the cooled air is blown out from the blower opening arranged above a passenger's head towards an upper body of the passenger. In this conventional system, heating operation and dehumidifying operation can be performed in addition to the above cooling operation. If the blower opening is formed at the ceiling of the passenger compartment, a comfortable heating operation to the passenger would be deteriorated because temperature of heated air becomes lower due to a long distance from the blower opening to passenger's feet. Furthermore, in the case of defrosting mode, a sufficient performance cannot be obtained, unless the blower opening is provided closer to the windshields. To overcome the above problems,
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multiple blower openings corresponding to the respective operational modes shall be provided at their appropriate positions in the passenger compartment, and multiple blower ducts shall be necessary for sending conditioned air from an air-conditioning unit mounted on a vehicle roof to the respective blower openings.
In such a system, however, multiple duct openings must be provided at the air-conditioning unit, and connecting portions for the multiple blower ducts and the multiple duct openings are inevitably provided at the roof opening formed at the vehicle roof. Consequently, it would be necessary to form a larger roof opening at the vehicle roof or to form multiple roof openings at the vehicle roof corresponding to the number of the blower ducts. In the case that an evaporator, a blower and other components constituting a refrigerating cycle are arranged in the air-conditioning unit, the weight of the air-conditioning unit becomes larger. When the air-conditioning unit of larger weight is mounted to the vehicle roof having the larger roof opening, reinforcing elements would become necessary to increase mechanical strength of the roof opening. As above, the air-conditioning unit is hardly mounted on the vehicle roof, when the air-conditioning unit has multiple duct openings.
Presently, the roof air conditioner is located outside on top of vehicles. In some vehicles the roof air conditioner is located inside the cabin on the roof. These systems are disadvantageous since they are large in size and weight, occupy more space for installing on roof and are connected to the central ducts which are passing throughout the vehicle to provide uniform air distribution and temperature distribution. The present system has limitations in providing
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uniform air distribution. Heat pickup and huge pressure drop occur when the cool and dehumidified air passes through these ducts. The present system also has limitations in maintaining the uniform temperature distribution inside the vehicle.
OBJECTS OF INVENTION
The main object of this invention is to provide an air conditioning roof unit which will give better uniform air and temperature distribution throughout the vehicle.
Another object of this invention is to provide an air conditioning roof unit which is simple in construction, compact, minimum weight, cost effective and easy to service.
Yet another object of this invention is to reduce the assembly time of air conditioning system on vehicle in production.
SUMMARY OF INVENTION
The air conditioning roof unit in accordance with this invention comprises
blower motors coupled with blower scrolls and placed inside the upper and lower casings of the air conditioning roof unit. Proximal to the blower assembly an evaporator is fixed and one end of the evaporator is connected to the thermostatic expansion valve and the other end is connected to the refrigerant
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pipeline. Proximal to the evaporator a filter is provided to remove the water droplets and dust, present in the cool and dehumidified air. Insulation is provided inside the said upper and lower casing of air conditioning roof unit in order to prevent the transfer of heat from inside of vehicle to the air conditioning roof unit. Drain hoses are connected to the lowermost part of the lowercasing of the air conditioning roof unit from sides.
A centre duct is connected to the said upper and lower casings and side ducts are projected from the extreme ends of said centre duct and extended towards the front of the vehicle. The side ducts extending from the ends of the centre duct are bent at the free ends to divert the air towards face of the passengers.
Deflectors are provided in said centre ducts at the extreme ends to deflect the desired quantity of air to the front of vehicle. Deflectors are also provided in said centre ducts at the bottom to deflect the desired quantity of air to the middle of vehicle.
A plurality of grilles are provided on the said air conditioning roof unit and are preferably placed at the outlet end, at the bottom end and at the end of the said ducts. The said grilles are adapted to be adjusted in the horizontal and /or vertical directions. The roof grilles at the bottom ends are fitted to the centre duct to swivel in one direction.
Said air conditioning roof unit has provisions, preferably brackets, to be mounted on the inside roof of the vehicle. Said roof unit is also provided with a cover inside of which is provided with an insulation lining
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Accordingly the present invention discloses an air conditioning roof unit comprising an upper and lower casing, at least one blower assembly placed inside the said casings, an evaporator fixed behind the said blower assembly one end of which is connected to expansion valve and other end is connected to refrigerant pipe line, a filter is provided beside the said evaporator and the insulation is provided inside the said upper and lower casing wherein a centre duct is connected to the said upper and lower casings and side ducts are projected from extreme ends of said centre duct and extended towards the front of the vehicle; a plurality of grilles are provided at the outlet end, bottom end and the said side ducts ends.
BRIEF DESCRIPTION OF DRAWINGS
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. 1 shows a front view of air conditioning roof unit in accordance with this invention
Fig.2 shows a rear view of air conditioning roof unit in accordance with this invention
Fig.3 shows a top view of air conditioning roof unit in accordance with this invention
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Fig.4 shows an exploded view of air conditioning roof unit in accordance with this invention
DETAILED DESCRIPTION OF DRAWINGS
Referring to figs. 1 to 4, the blower scroll (1) is coupled with blower motor (2) to suck and deliver the air from the cabin to the evaporator (3) for cooling and dehumidification. The first end of the said evaporator (3) is connected to a thermostatic expansion valve (4), which reduces the pressure and temperature of the refrigerant which passes through the evaporator (3) thereby removing the heat from the air passing over the said evaporator (3). The cooled and dehumidified air from the evaporator (3) passes through the filter (5), which is placed at a proximal distance preferably behind the evaporator (3). The second end of the said evaporator is connected to the refrigerant pipeline (7).
The filter (5) removes the water droplets and dust which pass along with the cool and dehumidified air through the roof grilles at the outlet end (9), roof grilles at the bottom end (10) and/or the roof grilles at the duct end (11) into the vehicle cabin. Drain hoses (8) are located at the sides of the bottom casing to drain the condensed water formed over the evaporator.
Insulation (6) is provided at the inner part of the upper casing (13) and lower casing (14) of the air conditioning roof unit in order to prevent the transfer of heat from inside of vehicle to the roof unit. The Insulation (6) also prevents
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condensation of water droplets formation on the outer part of the said upper and lower casings of the air conditioning roof unit.
The outlets of the said grilles on air conditioning roof unit are located at said three different places to provide the uniform air distribution and temperature inside the vehicle. Four grilles are located on the top of the said upper casing and two grilles are located on the bottom of the said lower casing of the air conditioning roof unit.
Ducts (12) are extended from the centre duct (17) at the extreme end the said centre duct of air conditioning roof unit through the roof, up to the front of the vehicle and side ducts are bent at the free ends to divert the air towards face of the passengers. Grilles (11) are located at the end of the said ducts and have provisions to adjust in horizontal (left and right) and vertical (up and down) direction according to the requirements and roof grilles at the bottom ends are fitted to centre duct to swivel in one direction. Said roof unit is provided with a cover (16) having insulation lining inside.. The air conditioning roof unit further comprises brackets (15) to mount the whole assembly on the inside roof of the vehicle.
The cool and dehumidified air is distributed through deflectors to all grilles in such a way that the air distribution and the temperature distribution are uniform through out the vehicle. The deflectors are provided in centre ducts at the extreme ends to deflect the desired quantity of air to the front of vehicle and also deflectors are provided in centre ducts at the bottom to deflect the desired quantity of air to the middle of vehicle. Air distribution to each grille outlet is
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Optimized through experiments for providing comfort to the passengers inside the vehicle. The arrangement is made simple with minimal layout of ducting to reduce the airside pressure drop and heat pickup while it is passing through the ducts.
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.
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WE CLAIM
1. An air conditioning roof unit comprising an upper and lower casing (13,14),
at least one blower assembly (1,2) placed inside the said casings(13,14), an
evaporator (3) fixed at a proximate distance from the said blower assembly(l,2), the first end of said evaporator (3) is connected to an expansion valve (4) and the second end is connected to the refrigerant pipe line(7), a filter (5) is provided proximal to the said evaporator (3) and an insulation (6) is provided inside the said upper and lower casing (13,14) to prevent the transfer of heat from inside of vehicle and condensation of water droplets formation on the outer part of the said upper and lower casings (13,14) of the air conditioning roof unit wherein a centre duct (17) is connected to the said upper and lower casings (13,14) and side ducts (12) are projected from extreme ends of said centre duct (17) and extended towards the front of the vehicle; a plurality of grilles are provided at the outlet end, bottom end and/or the said side ducts ends(9,10,l 1).
2. The air conditioning roof unit as claimed in claim 1 wherein said roof unit is provided with a cover having insulation lining disposed on its inside.
3. The air conditioning roof unit as claimed in claim 1 wherein a drain hose (8) is connected to the lower most part of the lower casing.
4. The air conditioning roof unit as claimed in claims 1 or 2 wherein said roof unit is provided with brackets to assemble the unit on the inside roof of the vehicle.
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5. The air conditioning roof unit as claimed in claim 1 wherein said grilles are provided to adjust in horizontal and /or vertical directions.
6. The air conditioning roof unit as claimed in claim 1 wherein deflectors are provided in said centre ducts at the extreme ends to deflect the desired quantity of air to the front of vehicle.
7. The air conditioning roof unit as claimed in claim 1 wherein deflectors are provided in said centre ducts at the bottom to deflect the desired quantity of air to the middle of vehicle.
8. The air conditioning roof unit as claimed in claim 1 wherein said side ducts are bent at the free ends to divert the air towards face of the passengers.
9. The air conditioning roof unit as claimed in claim 1 wherein said roof grilles at the bottom ends are fitted to centre duct to swivel in one direction.
10. Air conditioning roof unit substantially as herein described with reference to figures 1 to 4 of the accompanying drawings.
Dated this 28th day of February 2007
TATA MOTORS LIMITED By their Agent and Attorney
(KARUNA GOLERIA) of DePENNING & DePENNING
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ABSTRACT
Title: Air Conditioning Roof Unit
This invention relates to the air conditioning roof unit wherein blower motors are coupled with blower scrolls and placed inside the upper and lower casings of the air conditioning roof unit. Behind the blower assembly an evaporator is fixed and one end of which is connected to the thermostatic expansion valve and another end is connected to the refrigerant pipeline. Behind the evaporator a filter is provided to remove the water droplets and dust which are part of cool and dehumidified air. Insulation is provided inside the said upper and lower casing of air conditioning roof unit in order to prevent the transfer of heat from inside of vehicle to air conditioning roof unit. Drain hoses are connected to the lowermost part of the lowercasing of the air conditioning roof unit from sides. A centre duct is connected to the said upper and lower casings and side ducts are routed from extreme ends of said centre duct and extended towards the front of the vehicle. Grills are provided on the said air conditioning roof unit at the outlet end, at the bottom end and at the end of the said ducts. Said air conditioning roof unit have a provision to mount it inside the vehicle at roof. Said roof unit is provided with a cover having insulation lining inside said cover.


Documents:

388-MUM-2007-ABSTRACT(4-9-2009).pdf

388-mum-2007-abstract(granted)-(22-12-2010).pdf

388-mum-2007-abstract.doc

388-mum-2007-abstract.pdf

388-MUM-2007-CANCELLED PAGES(4-9-2009).pdf

388-MUM-2007-CLAIMS(4-9-2009).pdf

388-mum-2007-claims(amended)-(4-9-2009).pdf

388-mum-2007-claims(complete)-(28-2-2007).pdf

388-mum-2007-claims(granted)-(22-12-2010).pdf

388-mum-2007-claims.doc

388-mum-2007-claims.pdf

388-mum-2007-correspondance-received.pdf

388-MUM-2007-CORRESPONDENCE(1-10-2009).pdf

388-mum-2007-correspondence(10-4-2007).pdf

388-mum-2007-correspondence(ipo)-(2-1-2009).pdf

388-mum-2007-correspondence(ipo)-(22-12-2010).pdf

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

388-MUM-2007-DESCRIPTION(COMPLETE)-(4-9-2009).pdf

388-mum-2007-description(granted)-(22-12-2010).pdf

388-MUM-2007-DRAWING(4-9-2009).pdf

388-mum-2007-drawing(granted)-(22-12-2010).pdf

388-mum-2007-drawings.pdf

388-MUM-2007-FORM 1(4-9-2009).pdf

388-mum-2007-form 18(10-4-2007).pdf

388-mum-2007-form 2(4-9-2009).pdf

388-mum-2007-form 2(granted)-(22-12-2010).pdf

388-MUM-2007-FORM 2(TITLE PAGE)-(4-9-2009).pdf

388-mum-2007-form 2(title page)-(complete)-(28-2-2007).pdf

388-mum-2007-form 2(title page)-(granted)-(22-12-2010).pdf

388-MUM-2007-FORM 8(1-10-2009).pdf

388-mum-2007-form 9(10-4-2007).pdf

388-mum-2007-form-1.pdf

388-mum-2007-form-2.doc

388-mum-2007-form-2.pdf

388-mum-2007-form-26.pdf

388-mum-2007-form-3.pdf

388-MUM-2007-REPLY TO EXAMINATION REPORT(4-9-2009).pdf

388-mum-2007-specification(amended)-(4-9-2009).pdf

abstract1.jpg


Patent Number 244857
Indian Patent Application Number 388/MUM/2007
PG Journal Number 52/2010
Publication Date 24-Dec-2010
Grant Date 22-Dec-2010
Date of Filing 28-Feb-2007
Name of Patentee TATA MOTORS LIMITED
Applicant Address Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai 400 001,
Inventors:
# Inventor's Name Inventor's Address
1 IIANGO NAGAPPAN Bombay House , 24 Homi Mody Street, Hutatma Chowk, Mumbai 400 001
2 RANGANATH KUMAR S. V. Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai 400 001,
PCT International Classification Number B60H1/32
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA