Patent Publication Number: US-2023140582-A1

Title: Air conditioning system

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims the benefit of European Patent Office filing Patent Application No. 21461611.2, filed Oct. 29, 2021, entitled AIR CONDITIONING SYSTEM, which is incorporated herein by reference in the entirety. 
     TECHNICAL FIELD 
     The present disclosure is concerned with providing conditioned air to a space around a seated person in e.g. but not exclusively, a vehicle or an aircraft or in another area where the person is seated in a seat and requires cooled and/or warmed air for health and/or comfort. 
     BACKGROUND 
     Air conditioning systems are known in many fields to provide clean and comfortable air to people in enclosed spaces such as in rooms or vehicles. 
     Aircraft cabins, for example, generally have their air temperature regulated for the safety and comfort of passengers by an environmental conditioning system (ECS) that is controlled to ensure that the cabin air is clean and fresh and at the required temperature. In addition, passengers have air vents or blowers in the panel above their heads to provide additional cooling to the individual passenger as required. Passengers in business class or first class seats may also have individual heaters/coolers positioned under their seats. These passengers are able to adjust the temperature of the environment around their seat individually. 
     Whilst, as mentioned above, in aircraft the ECS operates to keep the cabin air comfortable, the fuel cost to cool the cabin air with conventional ECS systems is high. Where an aircraft is, for example, not full or where some passengers do not actually want or need the air temperature to be cooled to a given temperature, this is a wasted expense. 
     Design consideration is currently being given to increasing the efficiency of aircraft systems including reducing the fuel consumed in operating the ECS. Various ECS systems have been developed that e.g. use recirculated cabin air or other methods to reduce fuel consumption. Another way of reducing fuel consumption of the ECS that is currently being considered is to allow the cabin temperature to actually be higher than has conventionally been selected, thus requiring less fuel in cooling the cabin temperature. 
     A problem with this approach is that the higher cabin temperature might not be comfortable or optimal for every passenger. 
     As mentioned above, in some aircraft, passengers in areas of the cabin where the passenger has a relatively large seat space e.g. in business or first class may have their own individual air conditioning devices. These are usually in the form of a heat exchanger unit for example as described above, mounted in a manifold and located under the passenger&#39;s seat. The manifold usually has a number of outlets for the cooled or warmed air to exit to the seating area of the passenger. The manifold generally houses the heat exchanger components and has a flow channel for the air that has undergone heat exchange. The flow channel starts at an inlet which collects air from the heat exchanger, the channel then follows a circular path around the blower and has one or more outlets circumferentially offset with respect to the circular path from the inlet. The circular flow path may extend more than 360 degrees forming concentric circles around the blower. The overall width of the manifold is defined by the dimensions of the flow channel and the number for turns the channel makes around the blower—the more turns, the greater the width. 
     In business class and first class or similar parts of the aircraft cabin, there is generally enough space under the seat for a manifold of large enough surface area to provide sufficient temperature control to the passenger. In other parts of the cabin, such as economy class, for example, the seats are less wide and there is not sufficient area under the seats for the sorts of units currently used in the higher/more expensive class seat areas. This means that it is not feasible to have such individual environment control units under every passenger seat and so it has not been feasible to introduce fuel saving ECSs in aircraft that result in a higher overall cabin air temperature. 
     More compact heat exchanger systems are being developed that can be incorporated in other seat spaces. In addition, systems are being developed in which cooled (or warmed) air is channelled from the heat exchanger outlet through or behind the seat cushion forming the seat pad and/or back rest of the seat. Such systems can improve passenger comfort by providing comfortable temperatures where different parts of the person&#39;s body are located while the person is seated. This avoids one part of the person&#39;s body being cool and another part being warm. 
     Even with such temperature controlled seats, however, if the general temperature of the aircraft cabin (or other space where the person is seated) is relatively high (or cold), those parts of the person&#39;s body not in direct contact with the seat—e.g. the person&#39;s knees, thighs, chest, etc. may experience a temperature substantially warmer (or colder) than the rest of their body, which can cause discomfort. 
     There is, therefore, a need for an improved air conditioning assembly that can provide warmed or cooled air from a heat exchanger outlet to parts of the person&#39;s body that are not in direct contact with the seat pad and back rest. 
     SUMMARY 
     According to one aspect, there is provided an air conditioning system for a seat, comprising an arm rest of the seat, the arm rest having a top side, and inner wall and an outer wall, a front end and a back end defining a hollow interior between them, means for providing air conditioned to a desired temperature, from a source to the hollow interior of the arm rest, and a plurality of nozzles formed through the inner wall, defined between a nozzle inlet on an inner surface of the inner wall facing into the hollow interior and a nozzle outlet on an outer surface of the inner wall facing towards a seating area of a person when sitting in the seat, the nozzles providing a path through which air flows from the hollow interior, into the nozzle inlet and out of the nozzle outlet. 
     A conduit may direct air from a source of conditioned air into the hollow interior of the arm rest. 
     The nozzles may be shaped e.g. to form a straight flow path from their nozzle inlet to their nozzle outlet. Other shapes are also possible, e.g. the nozzle inlets may be offset with respect to the nozzle outlets to define a directed flow path. 
     One or more nozzles may also be formed through the top side and/or the front end of the arm rest. 
     The nozzles may have various locations e.g. they may be arranged in a plurality of rows along the inner side wall. 
     According to another aspect, there is provided a seat comprising a seat pad, a seat back and one or two arm rests defining between then a seating area for a person, and an air conditioning system as defined above for providing conditioned air to front parts of the body of a person sitting on the seat pad and resting against the back rest, via the plurality of nozzles. The air source may, for example, be located beneath the seat pad 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Non-limiting examples of assemblies according to the disclosure will now be described with reference to the drawings. It should be noted that variations are possible within the scope of the claims. 
       The examples are described as used in an aircraft passenger seat, but the same principles can be used in seats in other settings or locations and the disclosure is not limited to aircraft seats. 
         FIG.  1    shows a seat incorporating an air conditioning system according to an example of the disclosure. 
         FIG.  2    is a perspective partial view of a seat incorporating an air conditioning system according to an example of the disclosure. 
         FIG.  3    shows the seat of  FIG.  2    viewed from a different perspective. 
         FIG.  4    shows a cut-away detailed view of seat armrests according to the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The air conditioning system according to this disclosure makes use of the arm rest(s) of a seat to direct conditioned air inwards across the seat pad area such that the air is directed to the front of the body of a person sitting in the seat. The arm rest(s) of a seat are generally hollow and use can be made of the hollow space to incorporating one or more channels for the flow of conditioned air, the conditioned air is provided to the one or more channels in the arm rest(s) and outlet nozzles are provided in the side of the arm rest facing inwards towards the seating area of the seat where the seated person is located, the nozzles being shaped to eject conditioned air from the channel(s) in the arm rest(s) towards front parts of the person&#39;s body when seated e.g. the person&#39;s arms, knees, thighs and/or chest. Additional air nozzles may also be provided on other parts of the arm rest such as a top surface, where the user can rest their arm, and/or on the front end of the arm rest facing away from the seat back. 
     Examples of the system of the disclosure will now be described in more detail with reference to  FIGS.  1  to  4   . 
       FIG.  1    shows an example of a seat  1  having a seat pad  2  and a back rest  3  (i.e., seat back) together such that the person sits on the seat pad  2  and their back rests against the back rest  3 . The seat pad and the back rest can be adjustable relative to each other to allow for different seating positions to increasing the comfort of the person in the seat. The seat pad  2  and back rest  3  are generally provided with cushioning to improving comfort but the concepts of this disclosure may also be used in a seat without any cushioning. 
     The seat  1  is further provided with an arm rest  4   a ,  4   b  on either side of the seat pad  2  to allow the person seated in the seat to rest their arms in a comfortable position while seated. Although two arm rests  4   a ,  4   b  are shown, a seat may also be provided with only a single arm rest and/or may share an arm rest with an adjacent seat. 
     The position of the arm rests  4   a ,  4   b  may be fixed or may be adjustable relative to the seat pad  2 . For example, the arm rest may be pivotable to an open positioned, in which it is pivoted up towards the back rest  3  e.g. to allow the person to easily get out of the seat. In addition, or alternatively, the height of the arm rest  4   a ,  4   b  may be adjustable relative to the seat pad  2  to allow a comfortable rest position for persons of different side. Various shapes and sizes of arm rest are known. Arm rests can be contoured or shaped to be ergonomically advantageous or can be simply shaped where, for example, cost is a more important factor. Arm rests are commonly made of plastic material but other materials e.g. wood, metal etc. are also possible. Arm rests may be provided with a cushioned top surface to increase user comfort. 
     The seat is provided with an air conditioning system as described further below. 
     Conditioned air A, from a source of conditioned air (not shown) is provided to the interior of the arm rest(s)  4   a ,  4   b . The source of conditioned air may be a heat exchanger positioned beneath or behind or above or adjacent the seat  1 , but other sources are also feasible. The conditioned air may be conveyed from the source to the interior  10  of the arm rest  4   a ,  4   b  in any known way e.g. via channels or conduits. In some examples, conditioned air may also be provided to other parts of the seat, from the heat source, e.g. into the seat pad to provide a warming or cooling effect to the person&#39;s backside and the backs of their thighs in contact with the seat pad  2  and/or into the back rest to provide a warming or cooling effect to the person&#39;s back in contact with the back rest  3 . Whether the conditioned air is warm or cool will depend on the requirements of the person at any time, and on the environment, and will be determined by the conditioned air source or control, e.g. by the heat exchanger. If warming or cooling is also provided to the back of the person via the seat pad  2  and/or the back rest  3 , it may be desired to provide a corresponding effect, at the same or closely similar temperature to the front of the person. 
     The conditioned air A either fills a hollow cavity or flows through one or more channels  5  in the interior  10  of the arm rest and exits the arm rest via a plurality of openings or nozzles  20  formed through a side wall  41  of the arm rest that faces inwardly towards the seat area in which the person will be seated. The nozzles are shaped, located and directed in the side wall  41  so that the conditioned air can pass across the person&#39;s arms, knees, thighs and/or chest area when seated. The nozzles extend through the side wall  41  and are defined between a nozzle inlet  21  on the inner surface of the side wall  41 , facing into the interior of the arm rest, and a nozzle outlet  22  defined in the outer surface of the side wall  41 , facing into the seating area defined by the seat pad  2 . 
       FIG.  2    shows the basic structure of a seat having two arm rests with ventilation nozzles  20  according to the disclosure and  FIG.  3    shows the seat from the opposite side. It is also within the scope of the disclosure that even for a seat with two arm rests, as shown, only one of the arm rests is provided with ventilation nozzles. 
     The formation of the nozzles  20  in the side wall  41  of the arm rest  4   a ,  4   b  is shown in more detail in  FIG.  4   . The arm rest  4   a ,  4   b  has a top surface  40  on which the person&#39;s arm may rest, in use. Additional cushioning  400  or a protective cover may be provided over the top surface to provide additional comfort or to provide a removable and replaceable surface that can be easily removed and replaced in the event of damage or the like. Side walls  41 ,  42  extend down from the top surface  40  to form an inner side wall  41  facing towards the seated person, and an outer side wall  42  facing away from the seated person. The cut away view of  FIG.  4    shows the holler interior  10  of the arm rest defined by the top and side walls. 
     The arm rests  4   a ,  4   b  will also have a front facing end  43  and a rear end  44  attached to the structure of the seat  1 . 
     The conditioned air A from the air source (not shown—various sources are possible) is provided to the interior  10  of the arm rest e.g. via pipes or conduits (not shown). The way in which the air is provided to the arm rest is not important to this invention and various manners are conceivable. 
     The nozzles  20  are formed extending through the inner side wall  41  such that the air in the interior  10  of the arm rest exits the nozzles through their outlets  22  to the area where the person is seated. The nozzles  20  should be formed at locations in the side wall where the exiting air will flow across the person&#39;s thighs and/or chest. The actual location will depend on the design and position of the armrest. Additional nozzles (not shown) may be formed in the top surface and/or the front end of the arm rest. 
     The nozzles  20  may be circular such that the air exits in a straight path through the nozzle from its inlet  21  to its outlet  22 . Alternatively, the path through the nozzles  20  can be formed with some directionality e.g. so that the air is directed more towards the back of the seat, or more towards the person&#39;s chest or neck area, for example, by the nozzles being shaped so that the inlets and the outlets are slightly offset. 
     In the example, the nozzles  20  are formed in several rows across the side wall of the arm rest. The actual pattern, number and size of nozzles can be varied as required for any given situation. 
     The system provided by this disclosure allows a more personal and comprehensive air conditioning to be achieved using standard seat components and already available space in arm rests in a simple, inexpensive manner.