Apparatus for defrosting evaporator in refrigeration system using infrared emitting diode sensor

Abstract

An apparatus for defrosting an evaporator in a refrigeration system using an infrared emitting diode includes i) a frost detection sensor configured to receive a frost sensing signal from an output part of a control processor and to transmit a frost detection signal into an input part of a control processor, wherein the frost detection signal is generated by projecting infrared to the frost and receiving reflection-infrared from the frost; ii) a control processor configured to convert the frost detection signal into a digital signal in the signal converting part, to evaluate if the frost detection signal is higher than a threshold value which is set from a signal setting part, and to transmit the operation signal to the defroster, as well as the display signal to the signal display part; and iii) a defroster.

Claims

1. An apparatus for defrosting an evaporator in a refrigeration system using an infrared emitting diode sensor, the apparatus comprising: i) a frost detection sensor configured to receive a frost sensing signal from an output part of a control processor, and to transmit a frost detection signal into an input part of the control processor, wherein the frost detection signal is generated by projecting infrared radiation to frost and receiving reflection-infrared from the frost, wherein the frost detection sensor comprises a first infrared emitting diode (D1) configured to project the infrared radiation toward the evaporator under a standard voltage (V1) at an infrared emitting part; and a second infrared emitting diode (D2) configured to receive reflection-infrared from the evaporator at an infrared receiving part, wherein the frost is detected by measuring a signal voltage (V2) at the second infrared emitting diode (D2) that is lower than the standard voltage (V1); ii) the control processor configured to convert the frost detection signal into a digital signal in a signal converting part, to evaluate if the frost detection signal is higher than a threshold value which is set from a signal setting part, and to transmit an operation signal to a defroster and a display signal to a signal display part; and iii) the defroster configured to be operated depending on the operation signal from the control processor.

2. The apparatus for defrosting an evaporator according to claim 1, wherein the signal voltage (V2) that is measured is not lower than the standard voltage (V1) in a case that frost is not formed on the evaporator because absence of the frost does not produce infrared radiation interference with the infrared radiation from the first infrared emitting diode (D1), and wherein the signal voltage (V2) that is measured is lower than the standard voltage (V1) in a case that frost is formed on the evaporator because the presence of the frost produces infrared radiation interference between the infrared radiation from the first infrared emitting diode (D1) and the infrared radiation scattered by the frost.

3. The apparatus for defrosting an evaporator according to claim 1, wherein the control processor comprises i) the signal setting part in which defrost mode, defrost time, defrost method, defrost sensitivity, frost formation sensitivity and/or compulsory defrost period can be input and set; and ii) the signal display part in which setting defrost mode, setting defrost time, setting defrost method and/or alarm signal for defrosting evaporator can be displayed.

4. The apparatus for defrosting an evaporator according to claim 1, wherein a wavelength of the infrared radiation is 800950 nm and the standard voltage (V1) in the first infrared emitting diode (D1) at the infrared emitting part is 5V.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a block diagram indicating the construction of a frost detection sensor, a control processor and a defroster in the present invention. A control processor (60) includes a signal setting part (61) in which defrost mode, defrost time, defrost method, defrost sensitivity, frost formation sensitivity and/or compulsory defrost period can be input and set; and a signal display part (62) in which setting defrost mode, setting defrost time, setting defrost method and/or alarm signal for defrosting evaporator can be displayed.

(2) FIG. 2 shows the schematic view of defroster system in the present invention.

(3) FIG. 3a shows the detailed view indicating the infrared projection at infrared emitting part (51) as well as the detection-infrared projection at infrared receiving part (52) in case that frost is not formed on the evaporator.

(4) FIG. 3b shows the detailed view indicating the infrared projection at infrared emitting part (51) as well as the detection-infrared projection at infrared receiving part (52) in case that frost is formed on the evaporator. The infrared interference can occur between detection-infrared from infrared receiving part and reflection-infrared from frost.

(5) FIG. 3c shows another view as to another embodiment of frost detection sensor, in case that frost is not formed on the evaporator. The infrared is projected from infrared emitting part (51) and the projected infrared is not reflected from evaporator in case that frost is not formed on the evaporator. Therefore, reflected infrared cannot be detected at infrared receiving part (52).

(6) FIG. 3d shows another view as to another embodiment of frost detection sensor, in case that frost is formed on the evaporator. The infrared is projected from infrared emitting part (51) and the projected infrared is reflected from the frost on the evaporator in case that frost is formed on the evaporator. Therefore, reflected infrared can be detected by voltage generation at transistor (TR) in infrared receiving part (52).

(7) FIG. 4a shows the circuit constructing infrared emitting part (51) and infrared receiving part (52) in the frost detection sensor. Infrared emitting diode (D1) in infrared emitting part is applied to standard voltage (5V) and infrared emitting diode (D2) in infrared receiving part is applied to signal voltage (5V-reverse voltage).

(8) FIG. 4b shows the graph indicating the relationship between the signal voltage measured at infrared receiving part in frost defection sensor and the thickness of frost. According to increase of frost thickness, the signal voltage at infrared receiving part is declined due to the reverse-voltage generation. The threshold thickness of frost is represented by T.sub.1 and the signal voltage measured at this thickness is represented by V.sub.1.

(9) FIG. 4c shows another embodiment of circuit in another frost detection sensor. The infrared is projected from infrared emitting diode (D1) in infrared entitling part (51) to evaporator (20) under standard voltage. According to the density of reflection-infrared, the formation of frost can be measured by voltage generated at transistor (TR) in the infrared receiving part (52).

(10) FIG. 5 shows a schematic view of frost detection sensor. The frost detection sensor includes right and left attaching segment in front of sensor to be attached at the pin of evaporator.

(11) FIG. 6 shows a flow chart indicating the setting operation conditions of defroster in the control processor of present invention. According to the setting operation conditions, the defroster is operated by the signal from the control processor.

(12) TABLE-US-00001 Description of reference numeral 10. Cooling device 20. Evaporator 30. Frost 40. Reflection of infrared 50. Frost detection 51. Infrared emitting sensor part (D1) 52. Infrared receiving 60. Control processor 70. Defroster part (D2) 100. Evaporation pipe 110. Evaporation pin in evaporator

PREFERRED EMBODIMENT OF INVENTION

(13) The present invention relates to an apparatus for defrosting an evaporator in refrigeration system using infrared emitting diode sensor comprising: i) a frost detection sensor (50) configured to receive the frost sensing signal from the output part of a control processor (60), and to transmit the frost detection signal into the input part of a control processor (60), wherein the frost detection signal is generated by projecting infrared to the frost and projecting and receiving reflection-infrared from the frost; ii) a control processor (60) configured to convert the frost detection signal into digital signal in the signal converting part, to evaluate if the frost detection signal is higher than threshold value which is set from signal setting part (61), and to transmit the operation signal to the defroster (70) as well as the display signal to the signal display part (62); and iii) a defroster (70) configured to be operated depending on the signal from the control processor (60).

(14) The present invention can be explained more specifically in reference to attached drawings.

(15) FIG. 1 is a block diagram indicating the construction of a frost detection sensor, a control processor and a defroster in the present invention.

(16) The control processor (60) is a key element of the construction of present invention. The frost detection sensor (50) is connected with control processor (60) for communicating electric signals. Further, the defroster (70) is also connected with control processor in order to be operated for defrosting the evaporator.

(17) The frost detection sensor (50) includes infrared emitting part and infrared receiving part, which is connected with control processor (60) for communicating electric signals. The infrared is generated and projected from infrared emitting diode (D1) in infrared emitting part (51) under standard voltage, preferably 5V, into the evaporator (20). The detection-infrared is also generated and projected from infrared emitting diode (D2) in infrared receiving part (52) for measuring the signal voltage applied to infrared emitting diode (D2), which is declined compared to standard voltage due to infrared interference and photoelectric effect. Then, the measured signal in frost detection sensor is transmitted into control processor (60).

(18) Further, the analog voltage signal from the frost detection sensor is filtered and converted into the digital signal in the signal converting part of control processor (60). Then, if digital signal is higher than threshold value of frost, the operation signal from control processor is transmitted into defroster (70).

(19) Further, a control processor (60) includes a signal setting part (61) in which defrost mode, defrost time, defrost method, defrost sensitivity, frost formation sensitivity and/or compulsory defrost period can be input and set; and a signal display part (62) in which setting defrost mode, setting defrost time, setting defrost method and/or alarm signal for defrosting evaporator can be displayed.

(20) Finally, the frost formed on evaporator in refrigeration system has been defrosted by the operation of defroster (70), which is operated by the signal from the control processor (60). Of course, any kinds of defroster can be available, if the heating apparatus can defrost the evaporator.

(21) FIG. 2 shows the schematic view of defroster system in the present invention.

(22) As shown in FIG. 2, the frost detection sensor can measure the infrared interference signal alter projecting the infrared from infrared emitting part (51) to evaporator (20), reflecting the infrared (40) from the frost formed on evaporator and detecting and measuring the infrared interference at infrared receiving part (52).

(23) The wavelength of said infrared is in the range of 800950 nm.

(24) FIG. 3a shows the detailed view indicating the infrared projection at infrared emitting part (51) as well as the detection-infrared projection at infrared receiving part (52) in case that frost is not formed on the evaporator.

(25) If the frost is not formed on the evaporator, the infrared projected from infrared emitting part (51) is absorbed at evaporation pipe (100) or evaporation pin (110) in the evaporator. Therefore, infrared is not reflected from evaporator. Further, detection-infrared projected from infrared receiving part (52) is projected without any interference. Therefore, the voltage of infrared emitting diode (D2) in infrared receiving part (52) shall be same as the voltage of infrared emitting diode (D1) in infrared emitting part (51). The voltage of infrared emitting diode (D1) is preferably 5V.

(26) FIG. 3b shows the detailed view indicating the infrared projection at infrared emitting part (51) as well as the detection-infrared projection at infrared receiving part (52) in case that frost is formed on the evaporator. The infrared interference can occur between detection-infrared from infrared receiving part and reflection-infrared from frost.

(27) If the frost is formed on the evaporator, the infrared projected from infrared emitting part (51) is reflected from the frost on the evaporator. Therefore, infrared is reflected from evaporator. Further, detection-infrared projected from infrared receiving part (52) can have the interference with the infrared reflected from frost. Therefore, the voltage of infrared emitting diode (D2) in infrared receiving part (52) shall be declined than the voltage of infrared emitting diode (D1) in infrared emitting part (51) due to the infrared interference.

(28) FIG. 3c shows another view as to another embodiment of frost detection sensor, in case that frost is not formed on the evaporator.

(29) The infrared is projected from infrared emitting part (51) and the projected infrared is not reflected from evaporator in case that frost is not formed on the evaporator. Therefore, reflected infrared cannot be defected at infrared receiving part (52). Accordingly, voltage generation cannot occur caused by reflected infrared.

(30) FIG. 3d shows another view as to another embodiment of frost detection sensor, in case that frost is formed on the evaporator.

(31) The infrared is projected from infrared emitting part (51) and the projected infrared is reflected from the frost on the evaporator in ease that frost is formed on the evaporator. Therefore, reflected infrared can be detected by voltage generation at transistor (TR) in infrared receiving part (52).

(32) FIG. 4a shows the circuit constructing infrared emitting part (51) and infrared receiving part (52) in the frost detection sensor.

(33) Infrared emitting diode (D1) in infrared emitting part is applied to standard voltage (5V) and infrared emitting diode (D2) in infrared receiving part is applied to signal voltage (5V-reverse voltage). According to increase of reflected infrared, the reverse voltage also increases, which results in the decline of signal voltage at infrared emitting diode (D2). Therefore, the voltage of infrared emitting diode (D2) in infrared receiving part (52) shall be declined than the voltage (5V) of infrared emitting diode (D1) in infrared emitting part (51) due to the infrared interference.

(34) On the other hand, if the frost is not formed, the infrared is not reflected, which cannot result in reverse voltage generation. Therefore, the signal voltage in infrared receiving part shall be same as standard voltage in infrared emitting part.

(35) FIG. 4b shows the graph indicating the relationship between the signal voltage measured at infrared receiving part in frost detection sensor and the thickness of frost.

(36) According to increase of frost thickness, the signal voltage at infrared receiving part is declined due to the reverse-voltage generation. The threshold thickness of frost is represented by T.sub.1 and the signal voltage measured at this thickness is represented by V.sub.1.

(37) Of course, the threshold thickness of frost T.sub.1 can be measured by signal voltage V.sub.1 at infrared receiving part. Further, signal voltage V.sub.1 also can be set at the control processor (60) through the setting in signal setting part (61).

(38) FIG. 4c shows another embodiment of circuit in another frost detection sensor.

(39) In another embodiment of circuit, the transistor is replaced for measuring voltage instead of infrared emitting diode (D2) in preferred embodiment.

(40) The infrared is projected from infrared emitting diode (D1) in infrared emitting part (51) to evaporator (20) under standard voltage. According to the density of reflection-infrared, the formation of frost can be measured by the voltage generated at transistor (TR) in the infrared receiving part (52).

(41) FIG. 5 shows a schematic view of frost detection sensor. The frost detection sensor includes right and left attaching segment in front of sensor to be attached at the pin of evaporator.

(42) Further, the frost detection sensor (50) includes infrared emitting part containing infrared emitting diode (D1) and infrared receiving part containing infrared emitting diode (D2).

(43) FIG. 6 shows a flow chart indicating the setting operation conditions of defroster in the control processor of present invention. According to the setting operation conditions, the defroster is operated by the signal from the control processor.

(44) The control processor (60) includes a signal setting part (61) in which defrost mode, defrost time, defrost method, defrost sensitivity, frost formation sensitivity and/or compulsory defrost period can be input and set; and a signal display part (62) in which setting defrost mode, setting defrost time, setting defrost method and/or alarm signal for defrosting evaporator can be displayed.

(45) In this figure, the procedure for setting the defrost time, defrost mode, defrost method and frost formation sensitivity has been illustrated. Further, the procedure for setting the threshold frost formation sensitivity, defrost period and recognition delay time has been also illustrated.

(46) Further, if the signal over threshold value is transmitted from frost detection sensor (50) to control processor (60), the defroster (70) will be operated in accordance with the operation signal from control processor based upon the installed program. After complete removal of frost, defroster will be stopped in response to the signal detected from frost detection sensor (50).

(47) Further, the invention can minimize the operation time of defroster, because the operation of defroster is stopped by the real-time signal from the control processor at the time of removing frost on the evaporator. Of course, the cost of defrost can be saved efficiently according to the minimized operation time.