DESC:TECHNICAL FIELD
[001] The embodiments herein generally relate to evaporative air coolers, and more particularly, to an automatic control system for controlling operation of a pump and a fan (or blower) of an evaporative air cooler or the like.
BACKGROUND
[002] The air coolers available in the market perform the air cooling by means of a pump, a fan (or blower) and a cooling media including a honeycomb pad or woodwool. Said coolers have the following functional features: Pump: On/ Off, Fan Speed: High/ Medium/ Low and Swing: On/ Off.
[003] The conventional evaporative air coolers do not have the provision of automatically controlling the functioning of pump and fan during sleeping hours (i.e. when ambient temperature goes down during night). Prolonged operation of the air cooler at a pre-defined settings may not be desirable, as occupants of a room sleep, and their bodily functions slow down, causing a drop-in body temperature.
[004] The operation of the air cooler at the pre-defined settings during a period of time when cool air is not needed leads to wastage of electrical energy and discomfort to those sleeping in the room. Generally during the early hours of the morning, the user has to reduce the fan speed and/or switch off the pump or switch off the cooler to feel comfortable and not feel too much cold. The user needs to wake up from sleep and switch off the pump or change the fan speed of air cooler according to his/her requirement. The current available coolers do not have the provision where cooling and fan controls can be automatically adjusted as per a preset program.
[005] While the air cooler is usually operated between on and off states, the control portion allows the fan to be operated at a number preprogrammed fan speed settings that are selectable depending on the degree of cooling desired. In hot environments such as a room having windows through which sunlight directly enters the room, a first, high setting can be selected to operate the fan motor (114) near its maximum speed. When a minimal amount of cooling is desired, the control adjusted portion can be to operate the fan motor (114) at a second, low speed. Similarly, in moderate temperature environments, the control portion can be adjusted to another discrete, mid level setting to operate the fan motor (114) at an intermediate speed between the maximum and minimum speeds. Adjustment between the fan motor (114) speeds requires the user to select one of the preprogrammed speeds, which are often too fast or too slow to satisfy particular cooling demands. The existing air coolers allows the user to control the fan speed manually but does not provide any automatic control of the fan speed or cooling through water pump operation for controlling the water flow. The speed of water flow through water pump cannot be controlled automatically but water pump can only be switched on or off.
[006] A known art discloses a cooling device which relates to an apparatus and a method of controlling a sleeping mode of an air conditioner are provided to reduce energy consumption by decreasing the number of times of operations of a compressor, an indoor unit fan, and a discharging blade by controlling an indoor temperature by 1°C. An apparatus of controlling a sleeping mode of an air conditioner comprises a control unit, a timer, a user input unit, an indoor temperature sensor, a compressor, an indoor unit fan, and a discharging blade. The control unit includes the timer, and controls the entire operation of the air conditioner.
[007] Another known art discloses a cooling device which relates to an air handling system for cooling and/or heating a room includes a sleep mode. The system includes a fan assembly to transport air from the system into the room. A user interface transmits a sleep mode signal upon activation of the sleep mode by a user. A control unit controls the climate control unit to gradually change an ambient temperature in the room over a predetermined period of time in response to the sleep mode signal transmitted by the user interface. Further, the fan assembly has a substantially continuously adjustable speed within a range of speeds defined by a predetermined upper limit and a predetermined lower limit. The control unit adjusts the speed of the fan assembly according to a desired speed of the fan assembly input via the user interface. A multiposition switch defines the predetermined upper and lower limits.
[008] However, the cooling devices as described in the prior art do not have the provision of automatically controlling the functioning of the pump and the fan during sleeping hours when ambient temperature gets down and the user feels cold during sleep, as per the requirement of the user.
[009] Therefore, there exists a need for an automatic control system for controlling operation of a pump and a fan (or blower) of an evaporative air cooler, which obviates the aforementioned drawbacks.
OBJECTS
[0010] The principal object of the embodiments herein is to provide an automatic control system for controlling operation of a pump and a fan (or blower) of an evaporative air cooler or the like.
[0011] Another object of the embodiments herein is to provide an automatic control system for an evaporative air cooler which works based on a temperature feedback means.
[0012] Still another object of the embodiments herein is to provide an automatic control system for an evaporative air cooler which is simple in construction, hassle-free in operation and does not require human intervention.
[0013] Yet another object of the embodiments herein is to provide an automatic control system for an evaporative air cooler which requires minimal power for operation, and is efficient in cooling a confined space (surrounding environment).
[0014] Another object of the embodiments herein is to provide an automatic control system for an evaporative air cooler which ensures control of fan speed as well as provides temperature control, and can be used with windows in opened condition.
[0015] Still another object of the embodiments herein is to provide an automatic control system for an evaporative air cooler which facilitates in minimal water consumption and longer water retention in cooling mediums.
[0016] Yet another object of the embodiments herein is to provide an automatic control system for an evaporative air cooler which automatically sets the cooling level by way of a temperature setting or adjusting the blower speed, water supply or air flow control or similar settings based on surrounding environment to provide optimum cooling in an efficient manner.
[0017] Still another object of the embodiments herein is to provide an automatic control system for an evaporative air cooler which is able to control the fan speed of the cooler by controlling elements such as a fan motor (114) in combination with other elements such as a pump motor (112) (the motor in a cooling device which delivers water to the cooling mediums) by using temperature sensors.
[0018] Another object of the embodiments herein is to provide an automatic control system for an evaporative air cooler in which temperature sensors are placed at optimum locations to measure the required temperature, i.e. one sensor is placed on louvers in a path of air flow to measure a grill temperature of the air cooler and another sensor is mounted on a printed circuit board of the air cooler to sense the ambient temperature.
[0019] Also, another object of the embodiments herein is to provide a method for controlling an evaporative air cooler.
[0020] These and other objects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.
BRIEF DESCRIPTION OF DRAWINGS
[0021] The embodiments herein are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0022] FIG. 1 depicts a block diagram of an automatic control system for an evaporative air cooler, according to an embodiment as disclosed herein;
[0023] FIG. 2 depicts a perspective view of an evaporative air cooler, according to an embodiment as disclosed herein; and
[0024] FIG. 3 is a flowchart depicting a method for controlling an evaporative air cooler, according to an embodiment as disclosed herein.

DETAILED DESCRIPTION
[0025] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0026] The embodiments herein achieve an automatic control system for controlling operation of a pump and a fan (or blower) of an evaporative air cooler or the like. Further, the embodiments herein achieve the automatic control system for the evaporative air cooler which works based on a temperature feedback means. Furthermore, the embodiments herein achieve the automatic control system for the evaporative air cooler which is simple in construction, hassle-free in operation and does not require human intervention. Moreover, the embodiments herein achieve the automatic control system for the evaporative air cooler which requires minimal power for operation, and is efficient in cooling a confined space (surrounding environment). Additionally, the embodiments herein achieve the automatic control system for the evaporative air cooler which ensures control of fan speed as well as provides temperature control, and can be used with windows in opened condition. The embodiments herein further achieve the automatic control system for the evaporative air cooler which automatically sets the cooling level by way of a temperature setting or adjusting the blower speed, water supply or air flow control or similar settings based on surrounding environment to provide optimum cooling in an efficient manner. The embodiments herein achieve the automatic control system for the evaporative air cooler which is able to control the fan speed of the cooler by controlling elements such as a fan motor (114) in combination with other elements such as a pump motor (112) (the motor in a cooling device which delivers water to the cooling mediums) by using temperature sensors. Further, the embodiments herein achieve the automatic control system for the evaporative air cooler in which temperature sensors are placed at optimum locations to measure the required temperature, i.e. one sensor is placed on louvers in a path of air flow to measure a grill temperature of the air cooler and another sensor is mounted on a printed circuit board of the air cooler to sense the ambient temperature. Also, the embodiments herein achieve a method for controlling an evaporative air cooler. Referring now to the drawings, and more particularly to Figs. 1 through 3, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.
[0027] FIG. 1 depicts a block diagram of an automatic control system for an evaporative air cooler, according to an embodiment as disclosed herein. FIG. 2 depicts a perspective view of an evaporative air cooler, according to an embodiment as disclosed herein. For the purpose of this description and ease of understanding, the air cooler is explained herein below with reference to an evaporative air cooler. However, it is also within the scope of the invention to provide the control system for any other air cooling system or air conditioning system without otherwise deterring the intended function of the automatic control system as can be deduced from the description and drawings. In an embodiment, the evaporative air cooler (200) includes an external housing (202), a chamber (not shown), back air inlet grill (not shown), a left side air inlet grill (204), a right side air inlet grill (not shown), a water inlet (not shown), a top panel (not shown), a control panel (108), an air outlet grill (206), a water level indicator (not shown), a plurality of honeycomb pads (not shown), a water tank (not shown), a plurality of castor wheels (208), a control system (100), a water supply pump (not shown), a pump motor (112), a fan (not shown), and a fan motor (114). The evaporative cooler (200) as described above may include additional components or omit few components to operate efficiently. In an embodiment, the automatic control system (100) for controlling the evaporative air cooler (200) includes a microcontroller (102), a first sensor (104), a second sensor (106), a timer (110), and a PCB.
[0028] The automatic control system (100) for controlling the evaporative air cooler (200) includes the first sensor (104) which disposed at a predetermined position of the air cooler (200). The first sensor (104) is adapted to monitor and communicate an ambient temperature of the surrounding environment (or a space where the air cooler is located) to the microcontroller (102) as a temperature data. In an embodiment, the first sensor (104) is a thermistor which is adapted to measure of the ambient temperature. In an embodiment, the first sensor (104) is located on the printed circuit board (PCB) of the air cooler (200). However, it is also within the scope of the invention to the first sensor (104) in any desired location of the air cooler without otherwise deterring the intended function of the automatic control system as can be deduced from the description and drawings.
[0029] The automatic control system (100) for controlling the evaporative air cooler (200) further includes the second sensor (106) which is positioned in an air outlet path of the air cooler (200). In an embodiment, the second sensor (106) is mounted on the air outlet grill (206) which discharges the cool air from the housing of the air cooler (200). The second sensor (106) is adapted to monitor and communicate a temperature of discharged air to the microcontroller (102) as a temperature data. In an embodiment, the second sensor (106) is a NTC (negative temperature co-efficient) temperature sensor which measures air temperature at the outlet of the air cooler (200). In an embodiment, the temperature measured by the second sensor (106) is always lower than the actual ambient temperature, as the second sensor (106) is directly placed in the air flow path i.e. on the outlet of the air cooler (200) which delivers cool air to the surrounding environment.
[0030] Furthermore, the automatic control system (100) for controlling the evaporative air cooler (200) includes the microcontroller (102) which is embedded in printed circuit board (PCB) of the evaporative air cooler (200). The microcontroller (102) is configured to operate the evaporative air cooler (200) in accordance to a set of predefined instructions. The microcontroller (102) is adapted to receive temperature data measured by the first and second sensors (104 and 106). Further, the microcontroller (102) is configured to compare the temperature data received from the first and second sensors (104 and 106) with predetermined values stored in the microcontroller (102). In an embodiment, the microcontroller (102) may be integrally provided with a memory unit (not shown) to store a predetermined set of values. In an embodiment, the predetermined set of values stored in the microcontroller (102) is at least a lookup table.
[0031] For example, the table below provides a reference of a lookup table. The lookup table includes predefined temperatures and corresponding fan speed and pump duty cycle for each combination of the predefined temperatures.
Condition Ambient Temperature Grill Temperature Fan RPM Pump Duty Cycle time LED Indication Fan Speed LED Indication Pump
I Measured Ambient after every 300 secs Measured Grill after every 300 secs Speed level based on the temperature combination Duty Cycle based on the temperature combination LED to be indicated based on speed level LED to be indicated based on pump duty cycle

[0032] After comparing the temperature data with predetermined values the microcontroller (102) is adapted to generate control signals which are configured to control at least one of a duty cycle of the pump motor (112) and a speed of the fan motor (114) of the air cooler (200). The speed of the fan motor (114) is adapted to be varied between turbo, high, medium and low, and the duty cycle of the pump motor (112) is adapted to be varied between 0-100 %.
[0033] There are range of RPMs which are spanned across Turbo, High, Medium, Low i.e. the speed at which the motor is operated is identified and categorized as certain RPM levels. For example, the identified and categorized RPM levels may be turbo speed level when the motor is operated at a speed such as 1370, 1340. A turbo LED is configured to glow (ON) in case the speed level is turbo speed level. Similarly, when the motor is operated at high speed level, a high speed LED is configured to glow. Alike, when the motor is operated at other speed levels, a corresponding LED is configured to glow and unveil the speed at which the motor is operated.
[0034] In an embodiment, the control system (100) is capable of controlling the fan speed of the cooler by controlling elements such as the fan motor (114) in combination with other elements such as the pump motor (112) (the motor in a cooling device which delivers water to the cooling mediums) by using the temperature sensors. In an embodiment there are two temperature sensors located at suitable locations on the cooler which appropriately determine the room temperature. The fan speed of the motor (114) can be varied with a precision of, for example, 30 RPM due to use of variable speed motor and pump duty cycle can be varied from 0 to 100%.
[0035] Further, the microcontroller (102) is provided in communication with the timer (110). The timer (110) is adapted to activate the microcontroller (102) for a predefined period of time, to repeat a cycle of receiving the temperature data measured by the first and second sensors (104 and 106), and comparing the temperature data with the predetermined values, when the air cooler (200) is operated. The timer (110) activates the microcontroller (102) inorder to repeat the cycle whereby the microcontroller (102) monitors the temperature of the space where the air cooler (200) is located. The microcontroller (102) is adapted to generate an updated control signal for each of the repeat cycle, to perform one of varying the speed of the fan motor (114) and the duty cycle of the pump motor (112) to achieve desired predefined values or maintain same speed for the fan motor (114) and same duty cycle for the pump motor (112) when no change is required i.e. the temperature in the space has reached a desired predefined value. In an embodiment, the control signal generated by the microcontroller (102) is at least one of a start instruction, a shutdown instruction, a timing instruction, a temperature instruction, a motor operation instruction, and a water pump operation instruction.
[0036] The automatic control system (100) for controlling the evaporative air cooler (200) further includes a first relay assembly (not shown) and a second relay assembly (not shown). The microcontroller (102) is adapted to control the fan motor (114) by transmitting a first voltage signal through the first relay assembly. The first voltage signal is varied to by the microcontroller (102) to control the speed of the fan. In an embodiment, a first voltage signal supplied to the fan motor (114) is a DC voltage signal. Similarly, the microcontroller (102) is adapted to control the pump motor (112) by transmitting a second voltage signal through the second relay assembly. The second voltage signal is varied by the microcontroller (102) to control the duty cycle of the pump motor (112). In an embodiment, the second voltage signal supplied to the pump motor (112) is an AC voltage signal.
[0037] The control system (100) for controlling the evaporative air cooler (200) includes an indicating means for indicating the fan speed and the pump duty cycle. In an embodiment, the indicating means is at least a plurality of LED indicators. The LED indicators are mounted on the PCB such that they indicate the fan speed and the pump duty cycle by turning on with respect to the fan speed and the pump duty cycle.
[0038] FIG. 3 is a flowchart depicting a method for controlling an evaporative air cooler, according to an embodiment as disclosed herein. The method (300) for controlling an evaporative air cooler (200) includes providing a microcontroller (102) (at step 302). Further, the method (300) includes monitoring and communicating an ambient temperature, by a first sensor (104), disposed at a predetermined position of said air cooler (200) to said microcontroller (102) (at step 304). Furthermore, the method (300) includes monitoring and communicating a temperature of discharged air at an air outlet of said air cooler (200), to said microcontroller (102), by a second sensor (106) (at step 306). Moreover, the method (300) includes receiving, a temperature data measured by said first and second sensors (104 and 106) by said microcontroller (102) (at step 308). Additionally, the method (300) includes comparing, said temperature data with predetermined values, by said microcontroller (102) (at step 310). Also, the method (300) includes generating, at least one control signal to control at least one of a duty cycle of a pump motor (112) and a speed of a fan motor (114) of said air cooler (200) (at step 312). Further, the method (300) includes repeating, a cycle of receiving said temperature data measured by said first and second sensors (104 and 106), and comparing said temperature data with said predetermined values for a predefined period of time (at step 314). Furthermore, the method (300) includes generating, an updated control signal for each of said repeat cycle, to perform one of, varying said speed of said fan motor (114) and said duty cycle of said pump motor (112) to achieve predefined values, and maintain same speed for said fan motor (114) and same duty cycle for said pump motor (112) when no change is required (at step 316).
[0039] The advantages achieved by the embodiments herein include automatic adjustment of fan speed levels as per the surroundings, automatic control of water supply to cooling mediums, hassle-free operation, convenient especially during overnight operations, reduced power consumptions, minimal water consumption, longer water retention in the cooling mediums, assured energy saving, and capable to be extended to all types of evaporative air coolers like standalone coolers, tower coolers, personal coolers.
[0040] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
,CLAIMS:We claim,
1. An automatic control system (100) for an evaporative air cooler (200) having a pump and a fan, said control system (100) comprising:
a microcontroller (102);
a first sensor (104) disposed at a predetermined position of said air cooler (200), said first sensor (104) adapted to monitor and communicate ambient temperature to said microcontroller (102); and
a second sensor (106) positioned in an air outlet path of said air cooler (200), said second sensor (106) is adapted to monitor and communicate a temperature of discharged air to said microcontroller (102),
wherein,
said microcontroller (102) is configured to:
receive temperature data measured by said first and second sensors (104 and 106);
compare said temperature data with predetermined values stored in said microcontroller (102); and
generate control signals to control at least one of a duty cycle of a pump motor (112) and a speed of a fan motor (114) of said air cooler (200).

2. The control system (100) as claimed in claim 1, wherein said first sensor (104) is located on a printed circuit board (PCB) of said air cooler (200).

3. The control system (100) as claimed in claim 1, wherein said microcontroller (102) is provided in communication with a timer (110) which is adapted to activate said microcontroller (102) for a predefined period of time, to repeat a cycle of receiving said temperature data measured by said first and second sensors (104 and 106), and comparing said temperature data with said predetermined values, when said air cooler (200) is operated, wherein said microcontroller (102) is adapted to generate an updated control signal for each said repeat cycle, and perform one of adjusting said speed of said fan motor (114) and said duty cycle of said pump motor (112) and maintain same speed for said fan motor (114) and same duty cycle for said pump motor (112).

4. The control system (100) as claimed in claim 3, wherein said microcontroller (102) is adapted to generate control signal which is at least one of a start instruction, a shutdown instruction, a timing instruction, a temperature instruction, a motor operation instruction, and a water pump operation instruction.

5. The control system (100) as claimed in claim 1, wherein said microcontroller (102) is integrated with a first relay assembly, wherein said microcontroller (102) is adapted to control said fan motor (114) by transmitting a first voltage signal through said first relay assembly and said microcontroller (102) is integrated with a second relay assembly, wherein said microcontroller (102) is adapted to control said pump motor (112) by transmitting a second voltage signal through said second relay assembly.

6. The control system (100) as claimed in claim 1, wherein said speed of said fan motor (114) is adapted to varied between turbo, high, medium and low, wherein said duty cycle of said pump motor (112) is adapted to be varied between 0-100 %.

7. The control system (100) as claimed in claim 1, wherein said control system (100) includes an indicating means for indicating said fan speed and said pump duty cycle, said indicating means is at least a plurality of LED indicators, said LED indicators are mounted on said PCB.

8. The control system (100) as claimed in claim 1, wherein said predetermined values stored in said microcontroller (102) is at least a lookup table having predefined temperatures and corresponding fan speed and pump duty cycle for said predefined temperatures.
9. A method (300) for controlling an evaporative air cooler (200), said method (300) comprising:
providing a microcontroller (102);
monitoring and communicating an ambient temperature, by a first sensor (104), disposed at a predetermined position of said air cooler (200) to said microcontroller (102),
monitoring and communicating a temperature of discharged air at an air outlet of said air cooler (200), to said microcontroller (102), by a second sensor (106);
receiving, a temperature data measured by said first and second sensors (104 and 106) by said microcontroller (102);
comparing, said temperature data with predetermined values, by said microcontroller (102);
generating, at least one control signal to control at least one of a duty cycle of a pump motor (112) and a speed of a fan motor (114) of said air cooler (200);
repeating, a cycle of receiving said temperature data measured by said first and second sensors (104 and 106), and comparing said temperature data with said predetermined values for a predefined period of time; and
generating, an updated control signal for each of said repeat cycle, to perform one of, varying said speed of said fan motor (114) and said duty cycle of said pump motor (112) to achieve predefined values, and maintain same speed for said fan motor (114) and same duty cycle for said pump motor (112) when no change is required.

10. The method (300) as claimed in claim 9, wherein said first sensor (104) is located on a printed circuit board (PCB) of said air cooler (200).