Claims:We claim:

1. A temperature door (200, 300) for a heating, ventilation and air conditioning system (100), comprising:

a first element (202) having a plurality of apertures (206) defining a fluid flow path therethrough, and

at least one second element (204) juxtaposed the first element (202) and movable relative to the first element (202) between a block configuration in which the second element (204) at least partially blocks at least a set of apertures (206) and an unblock configuration in which the second element (204) at least partially unblocks at least the set of apertures (206), to vary the area of fluid flow path therethrough.

2. The temperature door (200, 300) of claim 1, wherein the first element (202) and the second element (204) having a planar surface.

3. The temperature door (200, 300) of claim 1, wherein the plurality of apertures (206) are arranged in rows and columns.

4. The temperature door (200, 300) of claim 1, wherein the second element (204) comprises a plurality of sub-sections (214) including a first set of sub-sections (214A) and a second set of sub-sections (214B), and the plurality of sub-sections (214) are arranged in correspondence with the arrangement of the plurality of apertures (206).

5. The temperature door (200, 300) of claim 4, wherein the first set of sub-sections (214A) connected to a first shaft (216), and the second set of sub-sections (214B) are connected to the first set of sub-sections (214A).

6. The temperature door (200, 300) of claim 4, wherein the first set of sub-sections (214A) are connected to the first shaft (216) and the second set of sub-sections (214B) are connected to a second shaft (218).

7. The temperature door (200, 300) of claim 1, wherein the first element (202) comprises at least two tracks (210, 212) extending from two opposite sides (208A, 208B) of each aperture (206).

8. The temperature door (200, 300) of claim 1, wherein each track (210, 212) is an L-shaped track, and each sub-section (214) has a shape complementary to the corresponding aperture (206) and adapted to slide between the tracks (210, 212) of corresponding aperture (206).

9. The temperature door (200, 300) of claim 1, further comprises at least one foam member (222) affixed to each sub-section (214) of the second element (204) such that foam member (222) is between the first element (202) and the second element (204).

10. A heating, ventilation and air conditioning system (100), comprising:

a blower assembly (110) for supplying air;
a first heat exchanger (112) located downstream to the blower assembly (110);
a second heat exchanger (120) located downstream to the first heat exchanger (112), and
a temperature door (200, 300) as claimed in claim 1 to 9 positioned between the first heat exchanger (112) and the second heat exchanger (120), the temperature door (200, 300) uniformly distributes at least a portion of airflow from the first heat exchanger (112) across the second heat exchanger (120).
, Description:A TEMPERATURE DOOR FOR A HEATING, VENTILATION AND AIR CONDITIONING SYSTEM

TECHNICAL FIELD
The present invention relates to a heating, ventilation and air conditioning system. In particular, the invention relates to a temperature door for a heating, ventilation and air conditioning system.

BACKGROUND
Generally, a HVAC module of a vehicle manages the temperature and distribution of air within the cabin of a vehicle. The HVAC module includes a housing having an inlet disposed on one end for receiving a flow of air and defines an upstream side of the housing. The housing further includes one or more outlets for dispensing the flow of air to the interior passenger compartment of the vehicle and defines a downstream side of the HVAC module. An air channel extends from the inlet on the upstream side of the housing to the outlets on the downstream side of the housing for conveying the flow of air there between. An evaporator is disposed in the air channel of the housing for dehumidifying and cooling the flow of air received from the inlet.

Downstream of the evaporator, the air channel transitions into a cool air path and a warm air path. A heater core is disposed in the warm air path of the air channel for heating the flow of air apportioned into the warm air path. Generally, the heater core is disposed in a housing having at least two openings. The at least two openings includes an upstream opening facing the evaporator and a downstream opening facing the outlets.

A system of doors are provided within the HVAC housing at key locations to control the amount of air flow through the heat exchangers and provide conditioned air into the interior passenger compartment of the vehicle. Particularly, the heater door is disposed between an evaporator and a heater to regulate the amount of cooling air passing from the evaporator to the heater core. The sliding heater door may include a first sliding door and a second sliding door. Each of the first sliding door and the second sliding door are connected to a respective driving assembly. The first sliding door may move downwards and the second sliding door may move upwards by operation of the respective drive assembly. In this way, the first sliding door and the second sliding door may move in a direction away from each other and may adjust the opening of the path to the heater. The sliding doors may create opening at a center portion of the airflow path. As the sliding door moves further apart, the width of the opening may increase. The opening is formed to expose only a particular portion of the heater and allows passage of air across the particular exposed portion of the heater. Therefore, this type of door arrangement fails to evenly distribute the airflow over the heater core, which limits the rate of heat transfer and majority of the air is poorly heated. A further effect of passing the majority of the air through the particular area of the heater core is a very high-pressure drop through the core.

Accordingly, there remains a need for a temperature door for a heating, ventilation and air conditioning system to maintain uniform distribution of air over the heater core for optimum heat transfer, and low-pressure drop.

SUMMARY
In the present description, some elements or parameters may be indexed, such as a first element and a second element. In this case, unless stated otherwise, this indexation is only meant to differentiate and name elements, which are similar but not identical. No idea of priority should be inferred from such indexation, as these terms may be switched without betraying the invention. Additionally, this indexation does not imply any order in mounting or use of the elements of the invention.

In view of forgoing, the present invention discloses a temperature door for a heating, ventilation and air conditioning (HVAC) system. The temperature door comprises a first element having a plurality of apertures defining a fluid flow path therethrough. The door further comprises at least one second element juxtaposed the first element and movable relative to the first element between a block configuration and an unblock configuration. In the block configuration, the second element at least partially blocks at least a set of apertures and in the unblock configuration, the second element at least partially unblocks at least the set of apertures, to vary the area of fluid flow path therethrough.

In one embodiment, the plurality of apertures are arranged in rows and columns. In one embodiment, the first element and the second element having a planar surface.

In one embodiment, the second element comprises a plurality of sub-sections including a first set of sub-sections and a second set of sub-sections, and the plurality of sub-sections are arranged in correspondence with the arrangement of the plurality of apertures. The first set of subsections connected to a first shaft and the second set of subsections are connected to the first set of sub-sections. In another embodiment, the first set of subsections are connected to the first shaft and the second set of sub-sections are connected to a second shaft.

In one embodiment, the first element comprises at least two tracks extending from two opposite sides of each aperture. Each track, for example, is an L-shaped track, and each sub-section has a shape complementary to the corresponding aperture and adapted to slide between the tracks of corresponding aperture. The temperature door further comprises at least one foam member affixed to each sub-section of the second element such that the foam member is between the first element and the second element. The foam member has a shaped complementary to the shape of the sub-section.

The present invention further discloses a heating, ventilation and air conditioning system. The system comprises a blower assembly for supplying air, a first heat exchanger located downstream to the blower assembly, a second heat exchanger located downstream to the first heat exchanger. The temperature door is mounted between the first heat exchanger and the second heat exchanger to uniformly distribute at least a portion of airflow from the first heat exchanger to across the second heat exchanger.
BRIEF DESCRIPTION OF THE DRAWINGS
Other characteristics, details and advantages of the invention can be inferred from the description of the invention hereunder. A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying figures, wherein:

FIG. 1 exemplarily illustrates a heating, ventilation and air conditioning (HVAC) system, according to an embodiment of the present invention;

FIG. 2 exemplarily illustrates a perspective view of a temperature door of the HVAC system of FIG. 1;

FIG. 3 exemplarily illustrates an exploded view of the temperature door of FIG. 2;

FIG. 4 exemplarily illustrates a front view of the temperature door of FIG. 2 in a blocked configuration;

FIG. 5 exemplarily illustrates a front view of a temperature door of the HVAC system of FIG. 1, according to another embodiment of the present invention;

FIG. 6 exemplarily illustrates an exploded view of the temperature door of FIG. 5;

FIG. 7 exemplarily illustrates the temperature door of FIG. 5 in unblocked configuration;

FIG. 8 exemplarily illustrates a track formed on the first element of the temperature door of FIG. 2 and FIG. 5;

FIG. 9 exemplarily illustrates the track with fillet formed on the first element of the temperature door of FIG. 2 and FIG. 5; and

FIG. 10 exemplarily illustrates a section of temperature door of FIG. 2 and FIG. 5 having a foam member disposed between the first element and the second element.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

It must be noted that the figures disclose the invention in a detailed enough way to be implemented, said figures helping to better define the invention if needs be. The invention should however not be limited to the embodiment disclosed in the description.

The present invention discloses a temperature door for a heating, ventilation and air conditioning (HVAC) system. The temperature door comprises a first element having a plurality of apertures defining a fluid flow path therethrough. The door further comprises at least one second element juxtaposed the first element and movable relative to the first element between a block configuration and an unblock configuration. In the block configuration, the second element at least partially blocks at least a set of apertures and in the unblock configuration, the second element at least partially unblocks at least the set of apertures, to vary the area of fluid flow path therethrough. The plurality of apertures defines a number of fluid flow paths and the plurality of apertures are arranged so that the number of flow paths corresponds to the entire region of the heater core. Further, varying the area of the apertures or the fluid flow path by the second element ensures uniform distribution of air across the heater core. Thereby the temperature door of the present invention maintain uniform distribution of air over the heater core, which results in optimum heat transfer, and low-pressure drop across the heater core.

Referring to FIG. 1, the HVAC system 100 includes a housing 102 having an inlet 104 and at least one outlet 106. The inlet 104 in fluid communication with a supply of air and is disposed on one end of the housing 102 for receiving a flow of air. The outlet 106 is disposed on the opposite end of the housing 102 from the inlet 104 for dispensing the flow of air to one or more zones of the vehicle. In an example, the supply of air can be provided from outside of the vehicle, recirculated from the passenger compartment, or a mixture of air from outside of the vehicle or the passenger compartment. The inlet 104 defines the upstream side of the housing 102 and the outlet 106 defines the downstream side of the housing 102. The housing 102 further comprises an airflow conduit 108 extending from the inlet 104 to the outlet 106 for conveying flow of air there between.
The system 100 further comprises a blower assembly 110 disposed externally of and adjacent to the inlet 104 for drawing air into the airflow conduit 108 of the housing 102. The HVAC system 100 further comprises an evaporator 112 or a first heat exchanger 112 disposed across the airflow conduit 108 for dehumidifying and cooling the flow of air received from the inlet 104. Downstream to the evaporator 112, the airflow conduit 108 transitions into a cool air path 114 and a warm air path 116. The HVAC system 100 comprises a partition wall 118 that bridges the cool air path 114 from the warm air path 116. The HVAC system 100 further comprises a heater 120 or a second heat exchanger 120 disposed in the warm air path 116 of the airflow conduit 108 for heating the flow of air apportioned into the warm air path 116. The HVAC system 100 further comprises a temperature door 200 or 300 (shown in FIG. 2 and FIG. 5, respectively) disposed across the warm air path 116 to control the airflow across the heater 120. The heater 120 comprises a casing (not shown) and a heater core enclosed in the housing 102. The casing generally includes at least two openings including a first opening facing the evaporator 112 and a second opening disposed opposing to the first opening and faces outlets 106 of the HVAC housing 102. The temperature door 200, 300 spans across at least a portion of the first opening to control the airflow across the heater 120.

Referring to FIG. 2, the temperature door 200 comprises at least one first element 202 and at least one second element 204. The first element 202 having a plurality of apertures 206 defining a fluid flow path there through. The second element 204 is juxtaposed the first element 202 and movable relative to the first element 202 between a blocked configuration and an unblocked configuration. In the blocked configuration, the second element 204 moves relative to the first element 202 and at least partially blocks at least a set of apertures 206 to vary the area of fluid flow path therethrough. In the unblocked configuration, the second element 204 moves relative to the first element 202 and at least partially unblocks at least a set of apertures 206 to vary the area of fluid path therethrough.

The first element 202 includes a substantially planar structure having the plurality of apertures 206. The plurality of apertures 206 are arranged in rows and columns. Further, a pair of track 210, 212 is formed on two opposing sides (208A, 208B) of the apertures 206. The second element 204 includes a plurality of subsections 214 that are arranged in correspondence with the arrangement of the plurality of apertures 206. The subsections 214 are arranged in rows and columns. The subsection 214 includes a substantially planar structure having a shape complementary to the shape of the aperture 206. Further, the second element 204 is connected to at least one shaft 216, 218. In one example, the second element 204 is connected to at least one shaft 216, 218. In one example, the apertures 206 and the subsections 214 has a rectangular shape. In another example, the apertures 206 and subsections 214 has a square shape. In yet another example, the aperture 206 and subsections 214 may have any other shape.

FIG. 3 exemplarily illustrates an exploded view of the temperature door 200 of FIG. 2. FIG. 4 exemplarily illustrates a front view of the temperature door 200 of FIG. 2 in a blocked configuration. Referring to FIG. 3 and FIG. 4, in this embodiment, the first element 202 comprises at least two sets of apertures 206 including a first set of apertures 206A and a second set of apertures 206B, and the second element comprises at least two sets of subsections 214 including a first set of subsections 214A and a second set of subsections 214B. The first set of subsections 214A is connected to a first shaft 216 and the second set of subsections 214B is connected to a second shaft 218, for example, via one or more connecting members 226. At least one connecting member 226 extends between each subsection 214 and the respective shafts 216, 218. The connecting member 226 is a planar block. In one example, the top portion of the first set of subsections 214A is connected to the first shaft 216 and the bottom portion of the second set of subsections 214B is connected to the second shaft 218. The two sets of apertures 206 are arranged in two rows and the two sets of sub-sections 214 are arranged in two rows. The first shaft 216 and the second shaft 218 may be alternatively referred as shaft 216, 218 throughout this document.

In one example, the shaft 216, 218 may be coupled to a driving member (not shown) to move the subsections 214 of the second element 204. The subsections 214 are adapted to slide over the aperture 206 to at least partially unblock or block the apertures 206. The track 210, 212 enables the subsections 214 to slide over the corresponding apertures 206. The apertures 206 may be sized smaller than the size of the subsections 214, which allows the subsections 214 to block or unblock the apertures 206 of the first element 202. In one embodiment, each subsection 214 may be individually controlled by the driving member to at least partially open and close the corresponding apertures 206.

FIG. 5 exemplarily illustrates a temperature door 300 for the HVAC system 100 of FIG. 1, according to another embodiment of the present invention. The temperature door 300 has same components as that of the temperature door 200. Hence, same numerals and same terms are used to refer the components of the temperature door 300 and reference may be made to the description of the temperature door 200. However, the arrangement of the subsections 214 and the connection of the subsections 214 to the shaft 216, 218 of the temperature door 300 is different from the temperature door 200.

The temperature door 300 comprises at least one first element 202 and at least one second element 204. The first element 202 includes a substantially planar structure having a plurality of apertures 206. The plurality of apertures 206 are arranged in rows and columns. Further, a pair of track 210, 212 is formed on two opposing sides 208A, 208B (shown in FIG. 8 and FIG. 9) of the apertures 206. The second element 204 includes a plurality of interconnected subsections 214 that are arranged in correspondence with the arrangement of the plurality of apertures 206. The subsections 214 are arranged in rows and columns. The subsection 214 includes a substantially planar structure having a shape complementary to the shape of the aperture 206. In one example, the subsections 214 are interconnected through, for example, one or more connecting members 226. Further, the interconnected subsections 214 are connected to at least one shaft 216 via, for example, the connecting members 226.

In one example, the apertures 206 and the subsections 214 has a rectangular shape. In another example, the apertures 206 and subsections 214 has a square shape. In yet another example, the aperture 206 and subsections 214 may have any other shape.

FIG. 6 exemplarily illustrates an exploded view of the temperature door 300 of FIG. 5. FIG. 7 exemplarily illustrates a front view of the temperature door 300 of FIG. 5 in a blocked configuration. Referring to FIG. 6 and FIG. 7, in this embodiment, the first element 202 comprises at least two sets of apertures 206A, 206B including a first set of apertures 206A and a second set of apertures 206B, and the second element 204 comprises at least two sets of subsections 214 including a first set of subsections 214A and a second set of subsections 214B. The top portion of the first set of subsections 214A is connected to the at least one shaft 216. The opposing bottom portion of the first set of subsections 214A is connected to the second set of subsections 214B. In one example, the shaft 216 may be coupled to the driving member to move the interconnected subsections 214 of the second element 204. The subsections 214 are adapted to slide over the aperture 206 to at least partially unblock or block the apertures 206. The track 210, 212 enables the subsections 214 to slide over the corresponding apertures 206. The apertures 206 may be sized smaller than the size of the subsections 214, which allows the subsections 214 to block or unblock the apertures 206 of the first element 202.

Referring to FIG. 8 and FIG. 9, each track 210, 212 of the temperature door 200, 300 has a first portion 210A, 212A and a second portion 210B, 212B. The first portion 210A, 212A has a first plane and extends along a side 208A, 208B of the aperture 206. The first plane is perpendicular to the plane of the first element 202. The second portion 210B, 212B has a second plane perpendicular to the first plane and extends in a direction towards the aperture 206 to define an L- shaped track. Referring to FIG. 9, the first portion 210A, 212A is provided with fillet 220 to provide additional strength and improve stiffness of the track 210, 212. Referring to FIG. 8, the track 210, 212 may be formed without fillet 220 while ensuring the strength and stiffness of the track 210, 212. In one example, each aperture 206 has a generally rectangular shape and includes the first side 208A and the second side 208B opposite to that of the first side 208A. At least one track 210, 212 extends from each of the first side 208A and the second side 208B of the aperture 206 and allows the subsection 214 to slide there between the tracks 210, 212 of the respective aperture 206.

Referring to FIG. 10, the temperature door 200, 300 further comprises at least one foam member 222 fixed to each subsection 214 of the second element 204 such that foam member 222 is between the first element 202 and the second element 204. The foam member 222 is provided to prevent air leakage through the stationary first element 202 and the movable second element 204. The foam member 222 is attached to the subsection 214, for example, through at least adhesive layer 224.

During operation, the HVAC system 100 conditions air by heating or cooling/dehumidifying the air and providing the conditioned air to the passenger compartment of the vehicle. The air is drawn into the airflow conduit 108 of the HVAC system 100 through the inlet 104, and flows to the evaporator 112. The air is cooled and dehumidified by transfer of heat from the air to a fluid circulated through the evaporator 112. The conditioned, cooled air stream then exits the evaporator 112. Then at least a portion of air is redirected to the warm air path 116. The temperature door 200, 300 is positioned to permit flow of air from the evaporator 112 to the heater 120 through the warm air path 116. The temperature door 200, 300 is configured to control the amount of air delivered across the heater 120 and uniformly distributes the air across the heater 120. The system 100 further comprises a control system connected to the driving member. In an example, the control system may be an electronic control unit of the vehicle.

Referring to FIG. 2 and FIG. 5, depending on the input from the control system, the second element 204 moves relative to the first element 202 between the blocked configuration and the unblocked configuration. The blocked configuration refers to movement of the second element 204 in a first direction, as depicted by arrow “D1”, to at least partially block at least the set of apertures 206. The blocked configuration further refers to movement of the second element 204 in the first direction to completely block the apertures 206, as shown in FIG. 4, and closes the warm flow path 116. The unblocked configuration refers to movement of the second element 204 in a second direction, as depicted by arrow “D2”, to at least partially unblock at least the set of apertures 206, as shown in FIG. 2. The second direction is opposite to that of the first direction. In other words, the first direction refers to movement of the second element 204 towards the apertures 206 to at least partially close the apertures 206 and

The driving member may drive the second element 204. For example, the driving member may be a gear having a rack and a pinion. The rack may be engaged with the second element 204. The pinion may be engaged with the rack, and may be driven by a servomotor.

The plurality of apertures 206 formed on the first element 206 spanning across the warm flow path 116 and the selective opening and closing of the apertures 206 by the second element 204 is configured to direct and distribute the air across the entire region of the heater core.

Referring to FIG. 4, the first shaft 216 is driven by the driving member, for example, linearly, to move the first set of subsections 214A in the first direction to close the first set of apertures 206A. The second shaft 218 is driven by the driving member, for example, linearly, to move the second set of subsections 214B in the first direction to close the second set of apertures 206B.

Referring to FIG. 2, the first shaft 216 is driven by the driving member, for example, linearly, to move the first set of subsections 214A in the second direction to at least partially open the first set of apertures 206A. The second shaft 218 is driven by the driving member, for example, linearly, to move the second set of subsections 214B in the second direction to at least partially open the second set of apertures 206B.

Referring to FIG. 5, the first shaft 216 is driven by the driving member, for example, linearly, to move the plurality of interconnected subsections 214 in the first direction to close or at least partially close the plurality of apertures 206 to block passage of air to the heater core. Referring to FIG. 7, the driving member is further configured to move the plurality of interconnected subsections 214 in the second direction to at least partially open the plurality of apertures 206 to allow passage of air to the heater core.

The plurality of apertures 206 defines a number of fluid flow paths and the plurality of apertures 206 are arranged so that the number of flow paths corresponds to the entire region of the heater core. Further, varying the area of the apertures 206 or the fluid flow path by the second element 204 ensures uniform distribution of air across the heater core. Thereby the temperature door 200, 300 of the present invention maintain uniform distribution of air over the heater core, which results in optimum heat transfer, and low-pressure drop across the heater core.

In any case, the invention cannot and should not be limited to the embodiments specifically described in this document, as other embodiments might exist. The invention shall spread to any equivalent means and any technically operating combination of means.