FIELD OF INVENTION:

The present invention relates to a service door panel for automotive heating, ventilating and air conditioning (HVAC) unit for the ease of cleaning the Evaporator without removing the HVAC unit from the vehicle.

BACKGROUND OF INVENTION:

The heating, ventilating and air conditioning (HVAC) unit is generally provided in the vehicle for supply of either cool or hot air inside the car cabin. Cooling effect is provided by extracting heat from the air in circulation thereby lowering the temperature.

This heat is extracted by the Heat Exchanger called Evaporator (child part of HVAC Unit). With progressive usage, dust present in the air gets accumulated on the Evaporator causing the formation of a layer of dust on the Evaporator surface.

This causes the reduction in heat exchange and air flow rate leading to performance deterioration over a period of time. Sometimes even bad smell comes in the cabin.

It is therefore recommended that the Evaporator must be cleaned in such eventualities but since HVAC unit is a closed unit and tightly fixed to the structure of the vehicle, it needs to be removed owing to non-availability of any service door for the purpose of cleaning

The Evaporator cleaning is a tedious process and main steps involved in this current Evaporator cleaning process are as follows:

o Refrigerant (A/C gas) recovery

o Engine Coolant recovery

o A/C Pipes & Heater Hose disassembly from HVAC Unit

o Instrument Panel removal

o HVAC Unit removal

o HVAC Unit opening & Evaporator removal

o Evaporator cleaning

o Evaporator fitment and HVAC Unit assembly

o HVAC Unit fitment on the vehicle

o A/C Pipes & Heater Hose Assembly on the HVAC Unit

o Instrument Panel fitment

o Coolant filling

o Refrigerant gas filling

As existing process for Evaporator cleaning involves many sub activities, it requires a lot of time and is costly.

Therefore, continuous efforts had been undertaken by the manufacturers, researchers to find a suitable solution to this tedious way of evaporator cleaning and different solutions had been patented.

Korean Patent No. 201999002948U on “EVAPORATOR ASSEMBLING OF PACKAGED AIR CONDITIONER” features a door (20) which has a door (4) to, as shown, the cabinet (11) to the rear surface of the opening formed in the (17) hinged to uniaxially and (24) is provided so as to freely turnable by the door (20), end portion of the door (20) for said cabinet (11) and at the same time the other side of door (20) opening in an elastic fixing piece for serving the function of handle (23) is formed. Such an indoor door of the existing method, cabinet (11) and which is provided for accommodating the evaporator (12) this material or due to dust and the like when the each other in the housing is a hook portion depending on, is cleaning evaporator periodically.

Further, the vibration sending and receiving members are in the device by the assembling structure of package air conditioner, cabinet (11) rear the evaporator to evaporate (12) for cleaning a rear of the door (20) is the cold air, evaporator (12) rear of the door (20) cleaning facilitated over is enabled.

This invention relates to provision of door on indoor unit of domestic air conditioner for ease of evaporator cleaning where there is no Space constrains and accessibility of tools for provision of such door. It does not cover any aspect of evaporator serviceability.

JP Patent Application No. 2013047044A on “HVAC UNIT FOR VEHICLE AIR CONDITIONING” described a HVAC unit for vehicle air conditioning which has improved in assemblability, and has largely raised productivity by reducing the number of parts.

It relates to a HVAC unit which includes a casing (2) that has an outside air introducing part (10), a vehicle interior air mixing port (12) and a filter installation/de-installation port (14); an vehicle interior air mixing door (20) that is attached to the casing to cover the vehicle interior air mixing port, and opens and close the vehicle interior air mixing port by the air pressure difference between an inner pressure of the casing and a pressure of the vehicle interior air, an vehicle interior air mixing absent specification cover (36) that has a filter installation/de-installation port blocking part (24) that covers the filter installation/de-installation port and an vehicle interior air mixing port blocking part (26) that covers the vehicle interior air mixing port; a vehicle interior air mixing present specification cover (30) that has an vehicle interior mixing opening port (28) that opens a filter installation /de-installation port blocking part, and the vehicle interior air mixing port blocking port. For the vehicle interior air mixing absent specification, the vehicle interior air mixing absent specification cover is attached to the outside of the casing, and for the vehicle interior air mixing present specification, the vehicle interior air mixing present specification cover is attached to the outside casing.

This invention relates to reducing and simplifying the assembly of air inlet box but does not cover any aspect of evaporator serviceability.

CN Patent Application No. CN 203147993U on “HEATING, VENTILATING AND AIR CONDITIONING (HVAC) AIR DOOR MECHANISM OF AUTOMOBILE AIR CONDITIONER” deals with a HVAC air door mechanism for a car air conditioner comprising a main air damper (1), detachable left air damper (2) , main damper shaft (9) on both side of the main air damper(1) and right damper (3).

The automobile air conditioner HVAC door mechanism is further characterized in that a nut (5) is provided on the main damper shaft (9), the left damper (2) and the right damper (3) are respectively provided with a bolt (4) matched with the nut (5).

This invention is related to splitting of face damper door in HVAC unit in multiple child parts for ease of assembly (and can be used for communization of damper in different HVAC models as well). It does not cover any aspect of evaporator serviceability.

As evident from above citations, the existing available HVAC units does not provide any facility for ease of easy cleaning of evaporator in HUAC unit instead of disassembly of HVAC unit in order to clean the evaporator in the unit requiring a lot of efforts and time.

In view of continuous efforts, there is still a need of a simple HVAC unit which has some arrangement of a service door panel on the side of unit which can be easily accessed so that by opening of the door panel from outside, the evaporator can be serviced without removing the evaporator (HVAC) unit from the vehicle for rendering the service while it is still mounted on the vehicle. This has been provided by the instant invention by providing, on one of the sides of HVAC unit, a service door panel fixed to the unit with snap lock provided on the easily accessible face of HVAC unit or hinging the service door panel from one side and snap-locked from other side or by sealing the door panel with the unit by use of either sealant or gasket. The subject invention is not only very cost effective and makes the servicing of the evaporator very easy and cheap by reducing the time required for servicing with this new HVAC unit with a service door panel.

OBJECTS OF THE INVENTION:

The main object of the invention is to provide an easy access to HVAC unit of the automobile vehicle for servicing of the Evaporator.

Another object of this invention is to reduce the time required to service the evaporator in HVAC Unit.

An additional object of this invention is to eliminate the need of HVAC unit removal from the vehicle for evaporator cleaning.

Yet another object of this invention is to make the cleaning of the evaporator of the automobile vehicle very cheap and ensure cost reduction.

The foregoing has outlined some of the pertinent objects of the invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the intended invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or modifying the invention within the scope of disclosure. Accordingly, other objects and a full understanding of the invention and the detailed description of the preferred embodiment in addition to the scope of the invention are to be defined by the claims taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

Further objects and advantages of this invention will be more apparent from the ensuing description when read in conjunction with the accompanying drawings wherein:

Figure 1 : Existing HVAC unit of automobile vehicle.

Figure 2 : Detailed view of service side panel on the easily
accessible side of HVAC Unit.

Figure 3 : Evaporator in HVAC unit of automobile vehicle.

Figure 4 : Water Jet direction for Evaporator surface cleaning.

While the invention is described in conjunction with the illustrated embodiments, it is understood that it is not intended to limit the invention to such embodiments. On the contrary, it is intended to cover all alternatives, modifications and equivalents which may be included within the spirit and scope of the invention disclosure as defined by the claims.

STATEMENT OF THE INVENTION:

According to the invention, there is provided a service door panel, for automotive Heating, Ventilating and Air Conditioning (HVAC) Unit, fixed or hinged on easily accessible side of the HVAC unit either by means of snap locks provided from the other side of HVAC unit or by means of gasket or sealant for locking said door panel in position. Further said service door panel which when opened, by releasing snap locks or gasket or sealant, provides an opening on the said side of HVAC Unit for the servicing of evaporator and for removing any foreign body accidently dropped in the system.

DETAILED DESCRIPTION OF THE INVENTION:

At the outset of the description, which follows, it is to be understood that the ensuing description only illustrate a particular form of the invention. However, such a particular form is only an exemplary embodiment and the teachings of the invention are not intended to be taken restrictively.

For the purpose of promoting an understanding of the principles of the invention, reference is now to be made to the embodiments illustrated and the specific language would be used to describe the same. It is nevertheless to be understood that no limitations of the scope of the invention is hereby intended on such alterations and further modifications in the illustrated bag and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

The embodiments are described with reference to the drawings in which like parts are referred to by like numerals. These embodiments are for illustrative purpose only and itshould be noted that invention is not limited to the embodiments illustrated in the drawings. Certain details, e.g. manufacturing / assembly details, have been omitted since they are not necessary to understand product functioning.

As used herein and subsequently in the claims, the singular form ‘a’, ‘an’, and ‘the’ includes plural reference unless the context clearly indicates otherwise.

The HVAC unit has many parts such as evaporator, heater, blower motor etc. Evaporator is the child part of the HVAC unit. The purpose of evaporator to extract heat from air and lower the temperature of air going into the vehicle cabin. Low temperature refrigerant flows through the evaporator which extracts the heat. The air flowing through the evaporator may pass through filter (if provided in the vehicle). Further considering the environmental conditions in India, air has many contaminants which are not filtered by external filter. Circulating of contaminated air in the evaporator causes deposition of contaminants on evaporator surface and thereby impairing its heat exchange efficiency.

Provision of filters in vehicles delays the clogging of evaporator. However, even in case of filter equipped system servicing is required. Servicing frequency increases in case filter is not equipped.

The present invention describes a door panel, for the Heating, ventilating and air conditioning HVAC unit which can be fixed or hinged on the easily accessible side of the HVAC unit either by means of snap locks provided on the other adjacent side of HVAC units or by means of gasket or sealant. In order to service the HVAC unit, the snap locks are opened thereby allowing the service door panel to be unwrapped or removed and service of the evaporator could be carried out without dismantling the HVAC unit from the vehicle as the evaporator is directly approachable from outside on account of said service door panel. The provision of service door panel reduces the time for servicing the evaporator and makes the operation very cost effective.

Figure 1 shows the HVAC unit (1), containing evaporator (2), which is tightly fixed in the front cabin room/compartment totally surrounded by firewall/dash panel or instrument panel and thus completely unapproachable from outside while it is in the mounted position.

In order to clean the evaporator as shown in Fig. 3, a door is required to provide access of cleaning equipments such as water jet, brushes, evaporator cleaner spray, air blower, vacuum line etc.

The door size is required to be kept optimum to minimize the leakage and to facilitate easy cleaning as well. Door shape and size can be designed suitably with respect to access, opening space, nearby area etc. for different types of HVAC.

The door can have hinged structure and/or snap lock for easy opening. The placement and type of the locking structure is based on the space availability and placement of components in the vicinity. In case of very less space the door can have all snap locks and can be removed after unlocking the snaps. Alternatively, door can have hinge support at one end and snaps on the opposite ends and door is rotated on hinge axis after snap unlocking in case of sufficient space availability.

The position of the door is such, as shown in Fig. 4, that the direction (5) of the cleaning equipment such as water jet nozzle, brushes, evaporator cleaner spray, air blower and vacuum line, should be at an angle, preferably 45o to 90o so as to clean the evaporator surface effectively.

The locks are never provided on inaccessible areas of the service door as it won’t be approachable from the bottom of the vehicle for ease of servicing.

Figure 2 shows HVAC unit enclosure wherein the service door panel (4) has been unwrapped from the HVAC unit enclosure thereby giving direct access to the evaporator from outside without any hindrance. When this service door panel is in open position, the service of the evaporator could be easily carried out with forced stream of water. There is no need to remove this HVAC unit from the vehicle for carrying out the service and to remove any foreign body accidently dropped into the system.

The sealing must be provided on all sides of the door to avoid leakage of air during HVAC unit operation. The sealing can be of any type, foam packing, Ethylene Propylene Diene Manomer (EPDM) or epoxy sealant etc.

In case the sealing is not proper, the air leakage will decrease the efficiency of HVAC. After the service it can be ensured manually that no leakage is there.

Presently, the HVAC unit enclosure is tightly fixed on the front cabin room/compartment of the vehicle. Since it is surrounded by dash panel/instrument panel and other mechanical /electrical devices in front cabin room of the vehicle leaving very insufficient place around the unit. Therefore it cannot be accessed from outside because of insufficient space around it. The unit has to be dismantled for servicing of the evaporator. However, the provision of service door panel as per instant invention removes this disability. Simple unwrapping/opening of service door panel serves the purpose, provides an opening to the Evaporator and HVAC unit can be serviced easily.

After cleaning of the evaporator, all the contaminants will flow down from the evaporator surface along with the water stream. The mixture of water and contaminant will be collected on the bottom of the evaporator. As the bottom side is inclined, it directs the water contaminant mixture towards the outlet drain (equipped in all HVAC units for condensate water drainage). Thus no contaminants remain inside the evaporator casing.

A rubber drain hose is provided on the HVAC unit drain outlet, which directs the mixture on the ground. As the contaminant size if very small and the possible of clogging the drain is very less. However, in case of clogging the drain passage can be unclogged after removing the drain hose and cleaning the passage externally by cleaning equipment. The cleaning equipment can be a wire, cable etc.

All documents cited in the description are incorporated herein by reference. The present invention is not to be limited in scope by the specific embodiments and examples which are intended as illustration of a number of aspects of the scope of this invention. Those skilled in the art will know or to be able to ascertain using no more than routine experimentation many equivalents to the specific embodiments of the invention described herein.

It is to be noted that the present invention is susceptible to modifications, adaptations and changes by those skilled in the art. Such variant embodiments employing the concepts and features of this invention are intended to be within the scope of the present invention, which is further set forth under the claims.

WE CLAIM:
1. A service door panel, for automotive Heating, Ventilating and Air Conditioning (HVAC) Unit, fixed or hinged on easily accessible side of the HVAC unit either by means of snap locks provided from the other adjacent side of HVAC unit or by means of gasket or sealant for locking said door panel in position.

2. The service door panel as claimed in claim 1 which when opened, by releasing snap locks or gasket or sealant, provides an opening on said side of HVAC Unit for the servicing of evaporator and for removing any foreign body accidently dropped in the system.

3. The service door panel as claimed in claim 1 and 2 wherein the position of door is such to allow the direction of the cleaning equipment, such as water jet nozzle, brushes, evaporator cleaner spray, air blower and vacuum line, at an angle between 45o to 90o so as to clean the evaporator surface effectively.

4. The service door panel as claimed in claim 1 wherein the sealant could be of any type, foam packing, EPDM or epoxy sealant.