Patent Application
20230081044
This disclosure relates generally to heat exchangers, and more particularly to a system and method for servicing a heat exchanger by detecting a clog in a heat exchanger component and cleaning the heat exchanger component.
A heat exchanger component (for example, a Heating Ventilation, and Air-Conditioning (HVAC) coil) installed in the heat exchanger may get clogged with dust and suspended particles in the air on an air side of the coil when exposed to air. Clogging may lead to reduced performance of a heat exchanger system and malfunctioning of the heat exchanger system further leading to complete failure.
Therefore, for minimizing an impact of the clogging, coils are required to be cleaned regularly or whenever the coil gets clogged. However, manual cleaning and maintenance of the coils may require large amount of time and effort. Additionally, concept of periodic cleaning of the coils at regular intervals may not be an optimum way of cleaning, as the clogging of the coils depends on varied environmental conditions in which the heat exchanger is being operated.
There is therefore a need in the art to provide a compact, an economically viable and effective automatic/semi-automatic system capable of detecting an extent of clogging on the coils, and the cleaning the coil in a minimal time span.
In an embodiment, a system for servicing a heat exchanger is disclosed. The system may include a clog detection assembly. The clog detection assembly may include a light source configured to be positioned on a first side of a component associated with the heat exchanger and further configured to illuminate the component with a projected light beam. The clog detection assembly may further include a light detector configured to be positioned on a second side opposite the first side of the heat exchanger component and further configured to detect transmitted light, in response to the projected light beam transmitting through the component, to generate a first signal corresponding to the transmitted light. The system may further include a processing device communicatively coupled to the light detector. The processing device may further include a processor and a memory configured to store processor executable instructions, which, on execution, may cause the processor to receive a first signal corresponding to the transmitted light from the light detector. The processor-executable instructions, on execution, may further cause the processor to analyze the first signal to detect presence of a clog in association with the component
In another embodiment a method of servicing a heat exchanger is disclosed. The method may include receiving a first signal corresponding to a transmitted light from a light detector. The light detector may be positioned on a second side of a component associated with the heat exchanger. Further, the light detector may be configured to detect transmitted light in response to a projected light beam projected by a light source and transmitting through the component to generate the first signal corresponding to the transmitted light. It should be noted that the light source may be positioned on a first side of the component opposite to the second side. The method may further include analyzing the first signal to detect presence of a clog in association with the component. The method may further include moving the cleaning nozzle across the component along a path upon detecting presence of the clog in association with the component. It should be noted that the path may be defined between a first position and a second position relative to the component. The method may further include causing the cleaning nozzle to spray a clog cleaning agent on the component during its movement along the path, from the first position (also referred to as homing position in this disclosure) to the second position (also referred to as path end position in this disclosure). The method may further include causing the cleaning nozzle to spray a pressurized fluid on the component during its movement along the path, from the second position to the first position relative to the component.
The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate exemplary embodiments and, together with the description, serve to explain the disclosed principles.
Exemplary embodiments are described with reference to the accompanying drawings. Wherever convenient, the same reference numbers are used throughout the drawings to refer to the same or like parts. While examples and features of disclosed principles are described herein, modifications, adaptations, and other implementations are possible without departing from the spirit and scope of the disclosed embodiments. It is intended that the following detailed description be considered as exemplary only, with the true scope and spirit being indicated by the following claims. Additional illustrative embodiments are listed below.
The disclosure pertains to detection of a clogging condition in heat exchanger components using a light source and a light detector (for example, a photodiode). For example, a heat exchanger component may be a Heating, Ventilation, and Air Conditioning (HVAC) coil. As light falls on the light detector or the photodiode, a voltage divider circuit may generate a voltage that may be proportional to amount of light intensity of the light source. Further, a decreasing light intensity may increase resistance in Light Dependent Resistors (LDR). Resistance is inversely proportional to the voltage, and thus when light is blocked on the LDR by dust or debris, less voltage may be obtained. A threshold value (for received light) may be defined as conditions indicating the presence of clog. When there is less voltage value than the threshold value of light intensity, it may indicate that the component may be clogged. This indication may be sent to and displayed on a dashboard or any handheld device to intimate a user about the clogging, so that cleaning process may be initiated. Examples of the handheld device may include, but are not limited to, iPads and laptops).
In an embodiment, cleaning of the clog may be performed in two steps. In a first step, a spray clog cleaning agent may be used and in a second step, an air pressure may be used to remove debris from the clog. The steps may be performed by using a cleaning nozzle which may move along a predefined path controlled by a micro controller. Further, an air compressor or blower may supply pressurized air to the cleaning nozzle via a multiport valve which may be controlled by the micro controller. The multiport valve may be opened by the micro controller when a clog cleaning agent is to be sprayed for cleaning. Thus, one pipe may account for both delivery of gaseous fluid and cleaning agent. After cleaning, the clog debris along with the cleaning agent may be drained through a drainpipe.
Referring now to
Further, the clog detection assembly 108 may include a light source 110, a light detector 112, and a transceiver 114. The light source 110 may be configured to be positioned on a first side of a component 122a associated with the heat exchanger 122 and further configured to illuminate the component 122a with a projected light beam. It should be noted that the component 122a may be a coil fin structure. The light detector 112 may be configured to be positioned on a second side opposite to the first side of the component 122a and further configured to detect transmitted light, in response to the projected light beam transmitting through the component 122a, to generate a first signal corresponding to the transmitted light. Examples of light detector 112 may include but are not limited to a photodiode, a LDR, a phototransistor or any photovoltaic devices. The transceiver 114 may be used to transmit and receive signals to and from the processing device 102. The clog detection assembly 108 may be operatively coupled to the clog cleaning assembly 116 via the processing device 102 and the heat exchanger 122.
The processing device 102 may be communicatively coupled to the light detector 112 of the clog detection assembly 108. The processor 104 may receive a signal transmitted from the light detector 112 via the transceiver 114 and further processes the signals as executable instructions to be followed by the clog cleaning assembly 116 upon detection of the clog. Examples of the processor 104 may include, but are not limited to, a microprocessor, a microcontroller, or a control logic. The memory 106 may be communicatively coupled to the processor 104 and store processor executable instructions. The processor executable instructions upon execution by the processor 104 may cause the processor 104 to receive a first signal corresponding to a transmitted light from the light detector 112 and analyze the first signal to detect presence of a clog in association with a component 122a.
Further, the processing device 102 may interact with a clog cleaning assembly 116. The clog cleaning assembly 116 may further include a multi-port cleaning nozzle 118 and may optionally include a transceiver. In some embodiments, the multiport cleaning nozzle may be referred as a cleaning nozzle. The multiport cleaning nozzle may include a multiport valve, through which a user can choose between a clog cleaning agent (i.e. cleaning fluid) and pressurized air. The clog cleaning agent may be retrieved from a cleaning agent reservoir, and the pressurized air may be obtained from a pressurized air source. The multiport cleaning nozzle may include a nozzle that may spray the fluid chose through the multiport valve, via a controller. It should be noted that the clog detection assembly 108, upon detection of a minimum clog threshold value (i.e. minimum voltage and maximum clog), may send information to the processing device 102. The processing device 102 further processes the information to the clog cleaning assembly 116. The clog cleaning assembly 116 may be configured to initiate a cleaning process. The multiport cleaning nozzle 118 upon receiving the processor executable instructions may move across the component 122a across a path. Further, the multiport cleaning nozzle 118 may spray a clog cleaning agent on the component 122a during its movement along the path, from a first position to a second position relative to the component 122a. Moreover, the multiport cleaning nozzle 118 may spray a pressurized fluid on the component 122a during its movement along the path, from the second position to the first position relative to the component 122a. The transceiver of the clog cleaning assembly 116 may be used to receive and send signals to the processing device 102.
It should be noted that the path may be a predefined a path. The path may be defined between a first position (For example, a homing position) and a second position (loop end position) relative to the component 122a. Also, it should be noted that the path may be generated in real time based on an analysis of the coil area.
Further, upon receiving the processor executable instruction, the processor 104 may first obtain a current position of the cleaning nozzle. In some embodiments, the processor 104 may cause the cleaning nozzle 118 to return to the first position, by moving along a reset path. The reset path may help in protecting the system 100 during a sudden power failure/power off/emergency stop condition. The reset path may be generated based on a predefined criterion. The predefined criteria may be selected from a set of predefined criteria. In some embodiments, the predefined criteria may be a first predefined criteria which may be based on a shortest path between the current position and the first position. Thus, in case of sudden failure, the cleaning nozzle may quickly reach the homing position. Further, in some embodiments, the predefined criteria may be a second predefined criteria which may be based on a quickest travel path between the current position and the first position. In some embodiments, the predefined criteria may be a third predefined criteria, which may be based on a least operation time of one or more motors configured to cause the cleaning assembly 116 move between the current position and the first position. In some other embodiments the processor 104 may cause the cleaning nozzle 118 to resume the path from the current position.
Referring now to
The system 200A may include a light source (similar to light source 110) configured to be positioned on a first side of the heat exchanger component and illuminate the heat exchanger component. A light detector may be configured to be positioned on a second side opposite the first side of the heat exchanger component and receive the light transmitted by the light source upon passing through the heat exchanger. The system 200A may be configured to receive a signal indicative of clog extent value, compare the clog extent value with a threshold clog value, and determine the presence of the clog cleaning based on the comparison.
Referring now to
V
out
=V
in×(R2/(RLDR+R)) equation (1)
It should be noted that in some embodiments, data acquisition (DAQ) may be used for conversion of luminance to resistance and for conversion of resistance to voltage. As such, a lookup table may be created and used via interpolation.
Referring now to
In an embodiment, a process flow in automatic detection and cleaning of the heat exchanger component may include the steps of: (i) turning OFF the heat exchanger system, (ii) turning ON the heat exchanger cleaning system from the dashboard, (iii) turning ON the heat exchanger clog detection switch, (iv) detecting clog from dust and debris using light source which may be (LED) and LDRs. The detection may be done using a following method, where a light intensity may be converted to resistance using LDRs. Theoretically, resistance may be converted to voltage using a voltage divider and after a calibrated drop of voltage, the cleaning process may be started. (v) If voltage comes below a calibrated value, the ‘Clog Detected’ LED may turn ON and if display feature is available, a percentage of clog may be detected. Then, the ‘Cleaning Enable Switch’ may be turned ‘ON’. On turning the switch ‘ON’ determine whether if the red LED appears indicating the presence of clog condition comes up. If the LED doesn't come up, it implies that the components are not fully clogged, and the cleaning process need not be initiated. (vi) An ‘Emergency Stop Switch’ may be present in the dashboard 300 to shut down the whole cleaning process in case of any emergency. If this is pressed, the whole cleaning process may be restarted by its own. This feature may enable the system to reset in case of any sudden power cut or any other unfavorable situations as well. (vii) Further, for the cleaning process to start first, the system may check for the compact box (containing the cleaning nozzle 118) in a homing position, and if the compact box is not in the homing position, the system may bring it to homing position first which is very necessary for the compact box to start executing the cleaning path. (viii) Once the compact box is in homing position which is detected by the stop switches, the cleaning process may start. (ix) Further, the cleaning process may make the compact box follow a specific optimized path to cover a specific coil area. The movement may be controlled by two motors with help of two lead screw rods. The movement may start from the homing position and the ending point may also be at same location. So, while traveling from the homing position, the compact box may spray a pressurized cleaning agent via a multiport valve and while returning the compact box may force pressurized gaseous fluid thus cleaning the coil clog. (x) Finally, after cleaning process, the system may be turned OFF.
Referring now to
Further the framework 400 may include a clog detection block 404. In some example embodiments, the clog detection block 404 may include three lux values, i.e. a lux value1 404a, a lux value2 404b, and a lux value3 404c. In alternate embodiments, any other number of three lux values may be used as well, i.e. the number of three lux values may vary based on the number of LDRs used. The clog detection block 404 may further include the clog present signal 404d to detect the presence of clog and a clog percentage signal 404e, which may represent the percentage of the present clog (on the dashboard) and compare it further with a predefined clog threshold value. Further the framework 400 may include a clog cleaning block 406, which may initiate the clog cleaning process upon receiving the cleaning enable signal 402g from the clog initiation block 402. The cleaning block 406 further includes a longitudinal motor I/P 406a to activate the longitudinal motor 408, a lateral motor I/P 406b to activate the lateral motor 410, a reservoir valve 406c, a compressor valve 406d, and a cleaning status 406e. Cleaning may be further explained in detail in conjunction with
Referring now to
Referring now to
The LEDs 602 may be used to indicate presence and condition of the clog. The LDR sensors 604 may receive lights of various intensities as an input including a lux value1 604a, a lux value2 604b, and a lux value3 604c, depending on the number of LDRs used. As mentioned above, the number of the lux values may not be restricted to 3 and may vary based on the number of LDRs used according to the requirement. Further, output of the LDR sensors 604 may be a resistance1 604d, a resistance2 604e and a resistance3 604f depending on the number of LDRs used. The number of resistances may vary corresponding to the number of lux values, and therefore may not be limited to 3. It may be noted that an average of the lux values and corresponding resistances may be determined. An average resistance value 606a may be transmitted to the resistance to voltage unit 606. The resistance to voltage unit 606 may further output a voltage 606b. Further, based on the voltage 606b, a clog percent signal may be generated, and a clog percentage may be determined.
Referring now to
The cleaning block may include a counter 702 for keeping a count of a time 702a. The counter 702 may be coupled to motor modules, a cleaning agent reservoir, and a gas compressor valve to initiate their respective timely responses. The cleaning block may further include a motor command 706, which may further include MotX 706a, MotY 706b and a cyclestart 706c. It should be noted that MotX and MotY are negative motion for the compact box to go to a homing position till the cycle start signal is actuated for the cleaning process startup. The motor command 706 may further receive information from the homing position (the terms ‘homing position’ and ‘first position’ may have been used interchangeably in this disclosure) detection block 704. The homing position detection block may further include X axis Stop Switch 704a and a Y axis StopSwitch 704b. The homing position detection block 704, upon receiving the processor executable instructions, may command the motors to locate and move towards the homing position when required.
The motor modules may include a longitudinal motor module 714 which may be associated with a longitudinal motor 714a. The motor modules may include may further include a lateral motor module 716 which may be associated with a lateral motor 716a. The cleaning block may include a valve key for cleaning agent spraying 718 associated with a reservoir valve 718a and a valve key for air compressor 720 associated with a compressor valve 720a. The system may further include represent a cleaning status 708.
Referring now to
The homing position 802 may be determined by a processing device, a component area 804, a path end position 806 (which may be a last working point of the component). It may be noted that the path of movement 800 may include a first cycle 808, which may be followed by the cleaning nozzle during the movement from the homing position 802 towards the path end position 806. Further, the path of movement 800 may include a return cycle 810, which may be followed by the cleaning nozzle during the movement from the path end position 806 towards the homing position 802.
Referring now to
Referring now to
At step 1002, a first signal corresponding to a transmitted light may be received. In particular, the signal may be received from a light detector (similar to the light detector 112). It should be noted that the light detector may be configured to detect transmitted light in response to a projected light beam projected by a light source (same as the light source 110) and transmitted through a component associated with the heat exchanger. Additionally, it should be noted that the light detector may be positioned on a second side of the component associated with the heat exchanger.
At step 1004, a first signal may be analyzed. The first signal may analyzed to detect presence of a clog in association with the component. It may be noted that the analysis of the signal may be executed by a clog detection assembly (analogous to the clog detection assembly 108) and a processing device (same as the processing device 102).
Thereafter, at step 1006, upon detection of the presence of the clog in a cleaning process may be performed to clean the clog detected in association with the component. Cleaning may be performed in various steps 1006a-1006c. At step 1006a, a cleaning nozzle (same as the cleaning nozzle 118) may be moved across the component along a path. The path may be defined between a first position and a second position relative to the component. Thereafter, at step 1006b, a clog cleaning agent may be sprayed on the component during its movement along the path by the cleaning nozzle, from the first position to the second position. At step 1006c, a pressurized fluid may be sprayed on the component during its movement along the path using the cleaning nozzle, from the second position to the first position relative to the component.
The disclosed invention works using LDRs which may detect an amount of light and may detect that the components are clogged or not. As is known, that as luminance varies as resistance varies and may be captured by supplying voltage. Thus, voltage may also vary. After a drop in voltage if a user switches to an auto clean, the system may start its automatic cleaning process. Further, the components may be cleaned by both a cleaning agent and pressurized air. Thus, whole cleaning process may be carried out without human efforts and in a very small span of time which may be calibrated by altering the codes.
The disclosed invention may enable the disclosed system to be both retrofitted and when given as an additional feature with heat exchanger systems would be a great impact to business. The system is very economical and may drastically reduce human effort for cleaning purposes. The system is robust and may need no maintenance of its own. The system may be able to clean the components in minimum amount of time. Further, the system may involve minimal cost and include multiple LDRs and LEDs, two stepper motors, two lead screw rods, two stop switches, one compressed gaseous fluid source (e.g., a compressor or a blower) and one microprocessor which can be standard of the self and can be reprogrammed as per the logic. The system may be robust and thus may have no need of maintenance as only a cleaning agent may be filled. In addition, no human efforts may be needed for opening the ducts and cleaning manually. The system may be incorporated in the heat exchanger system itself and thus may be powered from there or may be a separate unit be made for taking the power. The system may be calibrated depending on availability of light intensity present and may be configured separately for smooth detection of foreign particles such as dust and debris. As may be appreciated, if source of compressed gaseous fluid is present, then there may be no need to install a compressor or a blower and thus cost may be very less. Further, a smart application may be made to clean the components remotely and get notifications on personal/handheld or any other devices for cleaning when the components are clogged.
It is intended that the disclosure and examples be considered as exemplary only, with a true scope and spirit of disclosed embodiments being indicated by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202141041977 | Sep 2021 | IN | national |
