FIELD OF THE INVENTION

The present invention, in general is a low energy consumption air conditioning system, enabled by a second stage temperature booster.

BACKGROUND OF THE INVENTION

Air conditioning is a convenience that is ubiquitous in modern society. Air conditioning can be implemented using any of a variety of devices, and is typically used, for instance, to help- create comfortable indoor environments. Typical air conditioning systems employ a vapor- compression cycle to cool a targeted space. In a vapor-compression cycle, a refrigerant is circulated proximate the targeted space that is to be cooled, and is made to undergo iterative phase changes to continually remove heat from the targeted space and eject it outside of the targeted space. The setback of a typical air conditioning system is its typically high consumption of electricity, which is mainly driven by its compressor, a major component in the entire air conditioning system.

Therefore, methods to reduce energy consumption In air-conditioning system are found in the art. Among others, KR100883323B1 disclosed an air conditioner using thermal oil as the heating and cooling agent to improve efficiency through the use of simple and low eiectricity consumption. However, the use of thermal oil as heating and cooling agent depends on the thermal stability of the thermal oil.

Alternatively, an inverter air-conditioning system is used to control the speed of the compressor motor, so as to continuously regulate the temperature. The DC Inverter units have a variable-frequency drive that comprises an adjustable electrical inverter to control the speed of the electromotor. The variable-frequency drive converts the incoming AC current to DC and then through a .modulation in an electrical inverter produces current of desired frequency. A microcontroller is provided to each ambient air temperature and adjusts accordingly the speed of the compressor. The inverter air conditioning units have Increased efficiency in contraction to traditional air conditioners, extended life of their parts and the sharp fluctuations in the load are eliminated. However, the inverter AC units are more expensive than the constant speed a conditioners.

The present invention, a low energy consumption air conditioning system with a second stage temperature booster is developed as a solution to this setback and leads to a significant reduction in energy consumption of an air-conditioning system. While the inverter air conditioning systems consume less energy than ordinary systems, the present invention proved to be even more energy efficient and can also be combined with the inverter approach.

SUMMARY OF THE INVENTION

The present invention is a modified air conditioning system with a second stage temperature booster which results in significantly lower energy consumption of the air- conditioning system. The low energy consumption air-conditioning system (100) with second stage temperature booster comprising an indoor unit having an evaporator (102): an outdoor unit further comprising a compressor (104) connected to the indoor unit for receiving a low- pressure refrigerant and compressing the low-pressure refrigerant to a high pressure, high temperature, superheated gaseous state refrigerant; a condenser {106} for condensing the high pressure, high temperature, superheated gaseous state refrigerant into a sub-cooled liquid refrigerant with a high pressure and lower temperature; characterized in that; a heat exchanger is provided for a heat transfer of the refrigerant wherein the first connection of the heat exchanger (108) is a first set of heat transfer tubes {110} between trie compressor (104} and the condenser {108} which allows the Incoming refrigerant from the compressor (104) to release heat into the heat exchanger (108) before the refrigerant exits to the condenser 108);and a second connection of the heat exchanger (108) which is a second set of heat transfer tubes {112} between the condenser {108} and an expansion valve {114} wherein the refrigerant flows from the condenser {106) absorbs additional heat in the heat exchanger {108} and subsequently flows through the expansion valve (1 4), where an expansion of the refrigerant leads to a drop in temperature and pressure to provide the cooling effect before it exits to the evaporator ( 02).

In another embodiment of the present invention, a method of cooling a space using a low energy consumption air-conditioning system (100) comprising cooling and compressing a low-pressure refrigerant and compressing the low-pressure refrigerant to a high pressure, high temperature, superheated gaseous state refrigerant using a compressor (104); allowing the incoming refrigerant with high pressure, high temperature, superheated gaseous state refrigerant from the compressor {104 to enter a heat exchanger (108) to release the heat into a heat storage tank disposed adjacent to the outdoor unit of the air- conditioning system; after releasing the heat, the refrigerant subsequently exits the heat exchanger (108) and flows into a condenser (106) with high temperature and at pressure saturation point; condensing the high pressure., high temperature, superheated gaseous state refrigerant into a sub-cooled liquid refrigerant with nigh pressure and lower temperature using the condenser (108); returning the refrigerant to the neat exchanger (108) to absorb the heat in the heat exchanger (108) and transforms into a high pressure and high temperature liquid refrigerant with a larger expansion than the ordinary medium temperature and high-pressure liquid; flowing the low temperature and low-pressure liquid refrigerant to an evaporator of a cooling unit of the indoor unit (102) of the air-conditioning system {100} to form a low temperature and pressure saturation point liquid refrigerant; transforming the refrigerant which exits from the evaporator (102) into low temperature and low-pressure vapor which then flows back to the compressor (104) of an outdoor unit to complete a cycle and continuing circulating the refrigerant Within the air-conditioning system with low electricity current. As a result of the present invention, a significantly reduced energy consumption is achieved consistently.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

Figure 1. illustrates a diagram of the low energy consumption air-conditioning system in accordance with the present invention.

Figure 2 illustrates an isometric view of an outdoor unit of the low energy consumption air- conditioning system in accordance with the present invention. Figure 3 illustrates another Isometric view of an outdoor unit of low energy consumpt!or air-conditioning system in accordance with the present invention.

Figure 4 illustrates a side view of an outdoor unit of the low energy consumption air- conditioning system in accordance with the present invention.

Figure 5 illustrates a top view of an outdoor unit of the low energy consumption air- conditioning system in accordance with the present invention.

Figure 6 illustrates a front view of an outdoor unit of the low energy consumption air- conditioning system in accordance with the present invention.

Figure 7 illustrates a graph of lower consumption of 1 .5hp air conditioners from Panasonic (red), Daikin Inverter {light green) and the low energy consumption air-conditioning system of the present invention (light blue).

DETAILED DESCRIPTIONS OF THE INVENTION

The present invention will now be described in detail in connection with the specific embodiments with reference to the accompanying drawings. Unless the context requires otherwise, throughout the specification and claims which follow, the word "comprise" and variations thereof, such as, "comprises" and "comprising" are to be construed in an open, inclusive sense that is as "Including, but not limited to ^" . Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. With respect to the use of substantially any plural and/or ingular terms herein, those having skill In the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity, it will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "8" or "A and B." Note that throughout this description, the low energy consumption air conditioning system is described. In such, an air conditioning system is any system that conditions air with a temperature change, either making the air cooler (traditional) or warmer (reversed system). There is no limitation on the location of the air being conditioned such as within a building or room, within a chiller or "refrigerator," within a passenger compartment of a vehicle, within a cargo section of a tractor trailer or train, etc.

Figure 1 illustrates a schematic diagram of the low energy consumption air-conditioning system in accordance with the present invention. The low energy air-conditioning system (100) comprises an indoor unit and an outdoor facing side - often realized as split units with an indoor and an outdoor unit. The outdoor unit of the air-conditioning system {100) has a compressor (104) connected to the indoor unit (102) for receiving a low-pressure refrigerant and compressing the low-pressure refrigerant to a high pressure, high temperature, superheated gaseous state. A condenser { 106) condenses the high pressure, high temperature, superheated gaseous state refrigerant into a sub-cooled liquid refrigerant with high pressure and lower temperature. For the low energy consumption air-conditioning system of the present invention, a heat exchanger (108) is introduced into the refrigerant cycle, which transfers heat from the refrigerant. The first connection of the heat exchanger (108) Is a first set of heat transfer tubes (110) between the compressor (104) and the condenser (1 6) which allows the incoming refrigerant from the compressor ( 04) to release heat info the heat exchanger (108) before the refrigerant exits to the condenser (106). The second connection of the heat exchanger (108) is a second set of heat transfer tubes (112) between the condenser (108) and the expansion valve or capillary tube (114), where the refrigerant flows from the condenser (106) and absorbs additional heat in the heat exchanger (108). The refrigerant subsequentiy flows through the expansion valve or capillary tube (114), where an expansion of the refrigerant leads to a drop In temperature and pressure to provide the cooling effect. The refrigerant then exits to an evaporator (102).

In one preferred embodiment of the present invention, the heat exchanger is a preferably an aluminum container with a seal proof opening (or any material that can reasonably withstand heat of between 40*C and 150 ^!> C) as a heat storage tank with the size preferably 225 mm x 275mm x 700mm (D x W x H) disposed adjacent to the outdoor unit of the air- conditioning system {100). The heat storage tank preferably is an enclosed casing. The first set of heat transfer tubes {110} and the second set of tubes (1 2) are preferably a spiral copper piping to provide additional surface area for the refrigerant for heat to release in the heat exchanger (108) prior to entering into the condenser {106} and heat absorption in the heat exchanger 108) before it exits to the evaporator of the indoor unit (10 _. 2) of the air- conditioning system (100)

The total length of spiral copper piping is preferably 1000mm in length and 9.525 mm (3/8") in diameter of the tube for a 9,495.5kJ (9000 Btu) compressor, in the practice, the diameter of the tubes shall follow the diameter of the condenser of a 9.495.5kJ (9000 Btu) compressor. The spiral copper pipe will exit the condenser and connect to the expansion vaive used In the present invention, preferably a thermostatic expansion valve (TXV) or capillary tube. Among others, the modified expansion vaive Is provided with additional capillary tube diameter and length, preferably with a diameter of 6.35 mm {¼") with the length usual for a 12,660.7kj (12000 Btu) evaporator, to create higher energy expansion with the higher energy liquid refrigerant.

In another modification, the compressor used in the present Invention is smaller In capacity size than the conventional compressor for this size of air-conditioning system. For instance, a compressor of 9,495.5kJ (9000 Btu) is paired with the 12.660.7kJ (12000 Btu) capillary tube or the 12,660.7k J (12000 Btu) expansion vaive and 12,660.7kJ (12000 Btu) evaporator. The ratio of the pairing is as shown in Table 1. In addition, to achieve the optimum energy saving of the low energy consumption air- conditioning system of the present invention, further modifications are made to the low energy consumption air-conditioning system of the present invention, among others, a bigger sized evaporator and a smaller sized compressor are used as compared to the conventional air conditioning system.

In operation, the cooling process of a space using the low energy consumption air- conditioning system begins with cooling and compressing a low-pressure refrigerant and compressing the Sow-pressure refrigerant to a high pressure, high temperature, superheated gaseous state refrigerant using a compressor (104). The incoming refrigerant with high pressure, high temperature, superheated gaseous state refrigerant from the compressor (104) enters a heat exchanger (108) to release the heat in step (a) into the heat storage tank disposed adjacent to the outdoor unit of the air-conditioning system. Upon releasing the heat the refrigerant subsequently exits the heat exchanger (108) and flows into a condenser (108) with high temperature and at pressure saturation point in step (b).

Table 1 illustrates the pairing configuration between a compressor, the length of heat exchanger, capillary tube and its evaporator, in accordance with the present invention.

Subsequently, a condenser (108) condenses the high pressure, high temperature, superheated gaseous state refrigerant Into a sub-cooled liquid refrigerant with a medium temperature and high-pressure kquid in step (c). During this period, the refrigerant returns to the heat exchanger (108) in step (d), to aOsorh the heat in the heat exchanger (108) and transforms into a high pressure and high temperature liquid refrigerant with a larger expansion than the ordinary medium temperature and hsgh-pressure liquid in step (c). The liquid refrigerant wii! then flow into the expansion valve or capillary tube ( 14) and in step (e) transforms into low temperature and low-pressure liquid refrigerant. The low temperature and low-pressure liquid refrigerant then flows to an evaporator of a cooling unit g of the indoor unit {102} of the air-conditioning system {100} to form a low temperature and pressure saturation point liquid refrigerant in step {f}. After the refrigerant exits from the evaporator (102). the refrigerant wi!i transform into a low temperature and low-pressure vapor in step (g) which then flows back to the compressor (104) of an outdoor unit to complete a cycle. This process is called the second stage temperature booster. With this circulation of the refrigerant, the air conditioning system will consistently consume low electricity current.

Figure 2 illustrates an isometric view of an outdoor unit {200} of the low energy consumption air-conditioning system in accordance with the present invention. The outdoor unit (200) of an air-conditioning system can be paired and installed with any type of indoor unit for the purposes to achieve energy-saving and low electricity consumption. Among others, the outdoor unit {200} of the air-conditioning system having a compressor (202) connected to an indoor unit for receiving a low-pressure refrigerant and compressing the low- ressure refrigerant to a high pressure, high temperature, superheated gaseous state refrigerant. A condenser (204) of the outdoor unit (200) is provided for condensing the high pressure, high temperature, superheated gaseous state refrigerant into a sub-cooled liquid refrigerant with a high pressure and lower temper ature. Meanwhile, a heat exchanger {206} of the outdoor unit (200) is a container (208). The container (208) of the heat exchanger (206) is a heat storage tank disposed adjacent to the outdoor unit of the air-conditioning system. A first connection of the heat exchanger is a first set of heat transfer tubes {210) between the compressor (202) and the condenser {204} to allow an incoming refrigerant from the compressor {202} to release heat into the heat exchanger {206} before it flows to the condenser (204); while a second connection of the heat exchanger is a second set of heat transfer tubes (212) between the condenser (204} and an evaporator wherein an outgoing refrigerant flow from the condenser {204) returns to the heat exchanger {208} to absorb heat. The liquid refrigerant will then flow into the expansion valve or capillary tube {302) and transforms into low temperature and iow- pressure liquid refrigerant as illustrated in Figure 3 The low temperature and low-pressure liquid refrigerant then flows to an evaporator to form a low temperature and pressure saturation point liquid refrigerant.

The liquid refrigerant will then flow into the expansion valve or capillary tube {114} and in step (e) transforms Into low temperature and low-pressure liquid refrigerant. ^' The low temperature and low-pressure liquid refrigerant then flows to an evaporator (102) to form a low temperature and pressure saturation point liquid refrigerant in step (f . After the refrigerant exits from the evaporator (102), the refrigerant will transform into a iow temperature and low-pressure vapor ·η step {g) which then flows back to the compressor (104) to complete a cycle. This process is called the second stage temperature booster and with this circulation of the refrigerant, the air conditioning system will consistently consume low electricity current. in one of the embodiments of the heat storage tank (208) of the heat exchanger {2ϋδ} is provided with top opening for allowing the first set of heat transfer tubes (210) and the second set of heat transfer tubes (212) to be placed into the container {208} with a top cover (214) provided to seal heat released and absorbed within the heat exchanger (208). The heat transfer tube remains preferably within three-quarters (¾} In depth of the container. The first set of heat transfer tubes 1210} and the second set of tubes (212) used in the outdoor unit {200} are preferably a splrai copper piping {216} to provide addltiona! surface area for the refrigerant to release heat in the heat exchanger {208) prior to entering into the condenser {204} and heat absorbing in the heat exchanger (208) before it exits to the indoor unit of the air-conditioning system of the present invention. The diameter of the spiral copper piping used in the outdoor unit is preferably 9.525 mm (3/8"). In another embodiment of outdoor unit {200}, the expansion valve {302} is provided with additional capillary tub {218} diameter preferably with a diameter of 8.35 mm {¾") to create higher energy expansion with the high temperature refrigerant.

Figure 4 illustrates a side view of an outdoor unit of the low energy consumption alr- conditioning system in accordance With the present invention. This side view shows the view of the tube from the condenser (which has returned from the heat storage tank) and the connection to the capillary tube before exiting at the cold liquid valve leading to an evaporator. Figure 5 and Figure 6 illustrate a top view and a front view, respectively, of the low energy consumption air-conditioning system in accordance with the present invention.

The advantages of the low energy consumption air-conditioning system with second stage temperature booster are lower compressor suction superheat, greater amount of sub- cooling, more efficient compressor and condenser operation, improved compressor reliability and enhanced overall system performance, which results in the running of a low energy consumption air conditioning consistently.

Example

Below is a comparison between the low energy consumption air conditioning system of the present invention and two other types of conventional air-conditioning system available in the market. A screen capture of a graph was recorded, and the graph in Figure 7 shows the following variables: time versus kWh of power consumption of the three different air conditioning systems. All three air conditioning systems had the same capacity which is 12,660.7k J (12000 Btu) in capacity and were all programmed to run at temperatures of 16°C. The results were displayed on the real-time screen which was then recorded. The low energy consumption air conditioning is displayed as a light blue line (702), Datkin inverter is displayed as a light green line {704) and Panasonic is displayed as a red line (705) as shown in Figure ?. The low energy consumption air-conditioning system (702), which is the present invention, consumes the lowest electricity (kWh), which is estimated to be 15% lower than the inverter air conditioning system {704} and 50% lower than the conventional air conditioning system without inverter (706).

Table 2 shows the comparison between the low energy consumption air conditioning system with 1.5hp of the present Invention and Panasonic IShp air conditioning system (inverter). In conclusion, the low energy consumption air conditioning system of the present Invention has higher energy saving of up to 40% as compared to the inverter air conditioning system with the same horsepower. This is due to the lower running current throughout the operation of the low energy consumption air conditioning system of the present invention.

The foregoing detailed description and examples are merely Illustrative of the preferred embodiments. They are by no means meant to be the exclusive description of the inventive concept hereby disclosed. The present invention has been applied to various models of different capacities of the low energy consumption air conditioning from 1 horsepower up to 10 horsepower successfully, it will be recognized by one of ordinary skill in the art that certain aspects of the practice of the invention are readily susceptible to modification or practice by alternative, known means. Table 2. Comparison between low energy consumption air conditioning system with 1 of the present invention and Panasonic 1.5hp air conditioning system {inverter}

Specifications Low energy consumption air Panasonic Elite conditioning system of the Inverter SKY series present invention

Cooiing capacity (kVV) 3.6 3.6

Power input (W) 580 950

Running current (A) 2.7 4.4

Energy Efficiency Ration (EER) 16 5 13.6

Energy consumption per month 139 228 for 8 hours usage per day (kW)

Energy saving 40% -

P ice RM2600 (USD 613) RM2688 (USD 834}

Difference in price - R 88 (USD 21)