AU744608B2

AU744608B2 - Method of controlling air conditioner

Info

Publication number: AU744608B2
Application number: AU32399/99A
Authority: AU
Inventors: Ho Seon Choi; Seong Hoon Hahm; Gi Seop Lee
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 1998-06-11
Filing date: 1999-06-02
Publication date: 2002-02-28
Anticipated expiration: 2019-06-02
Also published as: CN1135335C; JPH11351646A; JP3239110B2; CN1239211A; KR100323541B1; AU3239999A; KR20000034767A

Description

-1- P/00/0011 Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name of Applicant: Actual Inventors: Address for service in Australia: Invention Title: LG ELECTRONICS INC.

Ho Seon CHOI, Gi Seop LEE and Seong Hoon HAHM CARTER SMITH BEADLE 2 Railway Parade Camberwell Victoria 3124 Australia METHOD OF CONTROLLING AIR CONDITIONER The following statement is a full description of this invention, including the best method of performing it known to us rr, :aP t; r~m!li~~ i IIIKWC~I~II -OTI-ijll~l-lr.

(1 i I: I r rL rl- i. _I METHOD OF CONTROLLING AIR CONDITIONER BACKGROUND OF THE INVENTION 1 Field of the Invention The present invention relates to a method of controlling an air conditioner for cooling room air, and more particularly, to a method of controlling an air conditioner, in which comfortable air cooling can be attained and excessive cooling of room air which may cause a sickness due to air conditioning can be prevented by determining the set temperature, air blow direction and air blow rate of the air conditioner by measuring cooling loads which vary with indoor and outdoor conditions.

2. Description of the Related Art In general, an air conditioner is provided with a refrigeration cycle system, and as shown in FIG. 1, the refrigeration cycle system is composed of a compressor 11 for compressing refrigerant so as to cause the temperature and pressure of the refrigerant to be raised, a condenser 12 for liquidizing the gas refrigerant at high temperature and is pressure supplied from the compressor 11, a capillary tube 13 for lowering the pressure of the liquidized refrigerant supplied from the condenser 12 and vaporizing a portion of the refrigerant, and an evaporator 14 for vaporizing the refrigerant supplied from the capillary tube 13 and cooling ambient air.

The operation of the refrigeration cycle system configured as above will be .*to described as follows. The refrigerant condensed in the compressor 11 is moved to the condenser 12 and condensed therein, and in the condenser 12, the refrigerant in a gas state is changed into a liquid refrigerant and emits thermal energy to the outside. The refrigerant from the condenser 12 undergoes pressure drop while passing through the capillary tube 13, and the refrigerant flowing through the capillary tube 13, a portion of which is vaporized according to the pressure drop is in a binary phase state in which liquid and gas phases of refrigerant coexist. The refrigerant decreased in pressure absorbs thermal energy while being vaporized in the evaporator 14.

That is, since the refrigerant requires a large amount of vaporization latent heat while being changed from a liquid state to a gas state, the surface of the evaporator 14 is cooled and air passing through the evaporator 14 is cooled. Therefore, since warm room air is cooled by the evaporator, and the cooled air is discharged by an indoor fan 15, room temperature is lowered. In addition, an outdoor fan 16 installed at one side of the condenser 12 blows air toward the condenser 12, discharges air heated due to the liquidization of the refrigerant out of an outdoor unit, and expedites the condensation of the refrigerant by supplying new air toward the condenser 12.

An apparatus which cools room air by using the above refrigeration cycle is an air conditioner. The air conditioner is classified into an integrated type air conditioner and a separated type air conditioner. In the integrated type air conditioner the whole refrigeration cycle system is included in a unit, and in the separated type air conditioner.

a compressor and a condenser which generate heat are installed at the outside of a room, and an evaporator is installed in the inside of the room. In general, the separated.

type air conditioner has a large cooling capacity, and the portion in which the compressor and condenser are installed is called an outdoor unit, and the other portion in which the evaporator is installed is called an indoor unit.

FIG. 2 shows an indoor unit of a conventional air conditioner.

Referring to FIG. 2, the indoor unit is composed of a suction grill 21 which is formed at a lower part of a case 20 and through which room air flows therein, a discharge grill 22 which is formed at an upper part of the case 20 and through which cooled air is discharged, an evaporator installed in the case 20 for cooling room air flowing through the evaporator 23, a temperature sensor 24 installed in front of the evaporator 23 for sensing room air temperature and an indoor fan 25 installed in the case 20 for forcing room air to flow inward unit and discharging cooled air outward. In addition, horizontal blow direction adjusting vanes 26 and vertical blow direction adjusting vanes 27 are installed at the discharge grill 22 for adjusting the discharging direction of air.

In the indoor unit structured as above, when the indoor fan is operated, room air is forced to flow inward and cooled by the evaporator 23, and the cooled air is discharged through the discharge grill 22. Therefore, room temperature is lowered.

When the indoor fan 25 is operated, room air is forced to flow into the case through the suction grill 21, and the sucked air is cooled while passing through the evaporator 23. The cooled air is discharged to the room through the discharge grill 22, S and the blow direction of the cooled air can be controlled as desired by using the horizontal and vertical blow direction adjusting vanes 26 and 27. In addition, the temperature sensor 24 controls the operation of the indoor fan 25 by sensing the temperature of room air flowing into the case In general, when an air conditioner is operated, cooled air is horizontally discharged from the discharge grill, and the cooled air currents flows toward the head portion or chest portion of a user in a sitting posture within a residing range (a range of 3 m in front of the air conditioner) when the cooled air is horizontally discharged 3 Therefore, the user feels discomfort due to feelings of a partial air flow or partially low temperature when a portion of body directly contacted by the cooled air flow is excessively cooled for a long time and the other portion not contacted by the cooled air flow remains warm.

In addition, frequency of room cooling using an air condition increases in summer, and patients due to air conditioning forms about 30% of medical patients.

Further, about 60% of the user of an air conditioner worry about an attack of a sickness due to air conditioning., General cause of the sickness due to air conditioning is an excessive temperature difference between indoor and outdoor temperatures, a direct air blow, a cooled air flow directly contacting a human body, a long stay in a conditioned room and the like.

For example, when the outdoor temperature rises to 35 0 C, indoor air conditioning is usually performed with a set temperature of 25'C. Therefore, the difference between indoor and outdoor temperatures is about 10 0 C, such an excessive temperature difference may cause a sickness due to air conditioning.

Though some Japanese companies produce air conditioners in each of which outdoor temperature is sensed by a temperature sensor attached to an outdoor unit of the air conditioner, this makes the cost of the air conditioner higher, and in addition the temperature around the outdoor unit cannot represent outdoor temperature and there.

is possibility that outdoor temperature is incorrectly sensed. That is, since the outdoor unit is usually installed beside a wall of a building or the housetop of a building, the temperature around such a place cannot represent outdoor temperature, and when the outdoor unit is installed at the outside of a house, outdoor temperature is incorrectly sensed due to a hot air blow from a neighboring outdoor unit.

4 fn In addition, in a general control algorithm for comfortable air conditioning, an air conditioner is controlled so that room temperature is conditioned to be at 26C regardless of other factors, but such control which does not consider the conditions beyond the adaptability of a human body to thermal environments may result in a sickness due to air conditioning. That is, while a human feels different comfortableness with the passage of time even when the human is continuously in a space keeping the same temperature of 26 0 C, a conventional control algorithm for comfortable air conditioning is indiscriminately concerned to simply control room temperature regardless of such a factor.

In fact, when the air conditioner is used, uncomfortableness arises from the following reasons. That is, when disparity exists between the cooling load of a room and the cooling capacity of an air conditioner, users feel discomfort.

First, the cooling capacity of an air conditioner dose not match with the actual cooling load of the installation space of the air conditioner. For example, when an air s conditioner adapted for a room area of 35 m 2 is installed in a 20 m 2 room, excessive i cooling is cause, and when the air conditioner is installed in a 50 m 2 room, uncomfortableness is caused due to a slow cooling rate.

Second, the cooling load of a room varies with whether the room is ventilated.

For example, even when an air conditioner adapted for a 20 m 2 room is installed in a 20 m 2 room, the user cannot feel coolness when a door or a window is opened since *o cooling cannot be sufficiently carried out.

Third, variations in outdoor temperature cause cooling load variations. Even in summer when an air conditioner is mainly used, outdoor temperature is not constant and varies depending on the time of day. Such variations in outdoor temperature have Ii~hr* i 4-9~:i -l.'.4449..9 4~~ Y 1 :1 z -i I -9 .i i i influence on indoor temperature. In summer, outdoor temperature increases fr -om morning, reaches a maximum temperature at around 13 14 o'clock, and then decreases. Such variations in outdoor temperature have influence on the temperatures of the outside walls of a house, and, in turn, on those of the inside walls by heat transfer. The temperatures of the inside walls have influence not only on hot or cool feeling or comfortableness of a human body, but also on the room temperature by radiation, and act as a cooling load.

The hot or cool feeling of a human body can be expressed by a PMVV (predicted mean vote) value, the PMVV which is proposed by professor P. 0. Fanger is determined by 6 factors of temperature, air flow velocity, humidity, and radiation temperature of the inside walls which are physical quantities of an air conditioning environment, and the amount of activity and the amount of clothing of a person which are individual environmental factors. That is, the PMV is formulated depending on the vote values acquired from an experiment in which about 1,300 subjects are exposed to various environments established by varying the 6 factors. When PMV it indicates that it is cod.h nP V 2 tidctsta ti o l h nP tidctsta is cldtyo, when PMV 2, it indicates that it is ootrl, when PMV 1, it indicates a that it is slightly warm, when PMV 2, it indicates that it is warm, and when PMV 3, it indicates that it is hot, and the thermal feeling scale as above is generally categorized in seven steps.

Fourth, the cooling load of a house varies with the direction of the house in which an air conditioner is installed. That is, a house facing the west generates a cooling load due to solar energy about 3 times that of a house facing the north, and the cooling load of a house varies with the wall thickness of a house and the floor on which a room is positioned in an apartment house.

Fifth, the cooling load of a room has relation to the number of dwellers in the room. That is, the body of a person radiates about 120 Kcal/h, and when the fact that S the cooling capacity of a 16 m 2 room is about 1,800 Kcal/h is considered, it can be found that the number of dwellers is an important factor in determining the cooling load of a room.

Sixth, the use of a heat emitting appliance, a computer or the like during the operation of an air conditioner increases the cooling load of a room. Since a large amount of heat is generated while such a heat emitting appliance or computer is used, the cooling load increases.

However, since a conventional air conditioner has no means for controlling temperature and air flow in response to the variations in the cooling load of a room, there are problems in which excessive cooling which may causes a sickness due to air conditioning occurs, and sufficiently comfortable air conditioning cannot be coco accomplished and it causes a user to feel discomfort.

SUMMARY OF THE INVENTION To solve the above problems, it is an objective of the present invention to provide a method of controlling an air conditioner capable of carrying out a comfortable air conditioning, preventing excessive cooling from occurring and thereby preventing a sickness due to air conditioning, and making the air conditioner consume less operating energy by controlling the set temperature, air blow direction, and air blow rate of the air conditioner so that the air conditioner can immediately respond to variations in the MI -'i cooling load, and, in addition, by controlling the operating state of the air conditioner considering the conditions beyond the adaptability of a human b ody so that a user does not feel cold.

Accordingly, to achieve the above objective, there is provided a method of controlling an air conditioner including the steps of: measuring cooling loads by detecting periods of time for which a compressor is on and periods of time for which the compressor is off while operating the air conditioner for a predetermined time in predetermined cooling conditions and comparing the dletected periods of time with reference time values determined in advance;, and responding to the measured cooling loads by changing a set temperature of the air conditioner and simultaneously changing at least one of the blow direction and blow rate of cooled air discharged from the air conditioner so that comfortable air conditioning can be attained according to the cooling loads measured in the step of measuring cooling loads.

In addition, to achieve the above objective, a method of controlling an air conditioner including the steps of: detecting. operation imnes. of an air conditioner operating at a predetermined set temperature after operating the air conditioner for a predetermined time in predetermined cooling conditions; deciding whether a condition beyond the adaptability of a human body occurs by comparing the operation times detected in the step of detecting operation times with time values classified by respective temperatures stored in a microcomputer for deciding whether a condition ****beyond the adaptability of a human body occurs;, and responding to the condition beyond the adaptability of a human body by changing a set temperature of the air conditioner and simultaneously changing at least one of the blow direction and blow 8

'V.

rate of cooled air discharged from the air conditioner in response to the temperature related to the decision in the deciding step.

In addition, to achieve the above objective, there is provided a method of controlling an air conditioner comprises the steps of: measuring cooling loads by detecting periods of time for which a compressor is on and periods of time for which the compressor is off while operating the air conditioner for a predetermined time in predetermined cooling conditions; responding to the measured cooling loads by changing a set temperature of the air conditioner and simultaneously changing the blow direction and blow rate of cooled air discharged from the air conditioner; deciding whether a condition beyond the adaptability of a human body occurs by comparing the operation times at respective temperatures according to the step of measuring cooling loads with time values classified by respective temperatures stored in a microcomputer for deciding whether a condition beyond the adaptability of a human body occurs;, and responding to the condition beyond the adaptability of a human body by changing a set temperature of the air conditioner and simultaneously changing the blow direction and blow rate of cooled air discharged from the air conditioner in response to the .:temperature related to the decision in the deciding step.

*BRIEF DESCRIPTION OF THE DRAWINGS The above objective and advantages of the present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the attached drawings in which: FIG. 1 is a schematic illustrating a general refrigeration cycle;, 9 FIG. 2 is a schematic side view illustrating the structure of a conventional air conditioner; FIG. 3 is a flow chart illustrating a method of controlling an air conditioner according to the present invention; FIG. 4 is a graph illustrating an operation example of an air conditioner in accordance with a method of controlling an air conditioner according to the present invention; FIG. 5 is a diagram illustrating times required for a compressor being turned on/off, when a method of controlling an air conditioner according to the present invention is applied to an air conditioner; FIG. 6 is a characteristic diagram illustrating the step of measuring cooling loads of a method of controlling an air conditioner according to the present invention; FIG. 7 is a diagram illustrating a method of controlling an air blow direction vertically; .5 FIG. 8 is a diagram illustrating patterns of controlling the air conditioner so as to respond to the condition beyond the adaptability of a human body when room temperature rises; FIG. 9 is a diagram illustrating patterns of controlling the air conditioner so as to respond to the condition beyond the adaptability of a human body when room temperature generally rises but falls at least one point; FIG. 10 is a graph of reference time versus room temperature concerning the conditions beyond the adaptability of a human body; and FIG. 11 is a block diagram illustrating an air conditioner employed in the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIGS. 3 and 4, a method of controlling an air conditioner according to the present invention comprises the steps of measuring cooling loads by detecting periods of time for which a compressor is on and periods of time for which the S compressor is off, responding to the measured cooling loads by controlling the operation state of the air conditioner according to the measured cooling loads, deciding whether a condition beyond the adaptability of a human body occurs to the air blow from the air conditioner by measuring the operation times of the air conditioner according to conditioned temperatures of a room during cooling operation, and responding to the condition beyond the adaptability of a human body by controlling the operation state of the air conditioner according to the condition beyond the adaptability of a human body.

The above-mentioned method of controlling an air conditioner according to the present invention is composed of two major categories of controlling the air conditioner so as to respond to cooling loads, and controlling the air conditioner so as to respond e to the condition beyond the adaptability of a human body.

The category of controlling the air conditioner so as to respond to cooling loads is composed of the steps of measuring cooling loads of a room by detecting periods of time for which the compressor is on and periods of time for which the compressor is off, responding to the measured cooling loads by controlling the operation state of the air conditioner according to the measured cooling loads, and checking a period of cooling time and deciding whether cooling loads are to be measured. Of course, the compressor is turned on or off when the temperature of the air flow sucked into the air conditioner is different from a preset temperature by a predetermined value.

11 The step of measuring cooling loads is composed of the steps of detecting times when the compressor is turned on and times when the compressor is turned off after the air conditioner is operated for a predetermined period of time at a preset temperature and a preset rate of air blow blown in a preset direction, measuring a spatial load by using the detected times when the compressor is turned on or off, and measuring a circumstantial load. The step responding to the measured cooling loads is composed of the steps of controlling a room temperature by changing the set temperature according to the cooling loads measured in the step of measuring cooling loads, controlling an air blow direction vertically in connection with a set temperature controlled according to the step of controlling a room temperature and controlling an air blow rate in connection with a vertical air blow direction controlled according to the step of controlling an air blow direction vertically.

At this time, in the step of controlling a room temperature, the set temperature is set with a regulation range having an upper limit value and a lower limit value, and in the step of checking a period of cooling time, a period of cooling time from the step of measuring cooling loads to the step of responding to the measured cooling loads is checked and the step of measuring cooling loads is restarted at a predetermined interval.

The category of controlling the air conditioner so as to respond to the condition beyond the adaptability of a human body is composed of steps of detecting operation times of the air conditioner at predetermined temperatures, respectively, after the air conditioner is operated for a predetermined time, deciding whether a condition beyond the adaptability of a human body occurs by comparing the detected operation times and the time values stored in a microcomputer, and controlling the operation state of the air 12 conditioner so as to respond to the condition beyond the adaptability of a human body.

Here, the time values stored in a microcomputer are experimental results, and a time value for a temperature was determined by measuring a time until a generally heathy person feels cold at the temperature when the person is continuously exposed to the temperature.

In the step of deciding whether a condition beyond the adaptability of a human body occurs, when any one of the summed operation times at respective temperatures during cooling operation until this step begins is longer than the time values stored in the microcomputer, the microcomputer decides that the room air is "cold" and decides to respond to the condition beyond the adaptability of a human body. Here, when the room temperature rises without falling, the operation time at one temperature is decided by taking the operation time at the elevated temperature without considering the operation time data of the same temperature before the temperature is reached, and when the room temperature falls, the operation time at one temperature is decided by summing the operation times at the temperature until this step begins.

The step of responding to the condition beyond the adaptability of a human body comprises the steps of controlling the room temperature by changing the set temperature so that the room temperature is controlled to be appropriate for a human body, controlling a blow direction of cooled air discharged from the air conditioner upward by a predetermined degree so that the human body does not feel the air blow, periodically changing the horizontal direction of air blow from side to side, and controlling an air blow rate in the "weak" mode. At this time, in the step of changing the set temperature, the set temperature can be changed within a predetermined range having an upper limit value and a lower limit value, and when the room temperature is controlled by the upper limit value, the operation of a compressor is stopped for a predetermined time at the point of time when the summed opera tion time corresponding to the upper limit value is larger than the reference time stored in the microcomputer corresponding to the upper limit value for deciding whether a condition beyond the adaptability of a human body occurs.

The method of controlling an air conditioner configured as above controls the operation state of the air conditioner according to variations in the cooling loads, and can establish comfortable air conditioning by controlling the air conditioner so that the room temperature is controlled to respond to the condition beyond the adaptability of a human body.

When the air conditioner is operated to respond to the cooling load of a room, the air conditioner is initially operated in conditions in which a set temperature is 26'C, an air blow rate is in the "weak" mode, and a vertical air blow direction is set to be a V as shown in FIG. 7. When the room temperature reaches the set temperature, the 5 compressor is turned off first time, and the point of time is indicated by nO. The interval from the point nO to the point n2 on which the compressor is turned off third time Is termed a first measuring step of measuring cooling loads.

The first measuring step of measuring cooling loads is divided into the step of measuring a spatial cooling load and the step of a circumstantial cooling load, and in to measure the cooling loads operation times of the compressor are detected.

That is, the time t1 required for the compressor being turned off and the time t1 (n) required for the compressor being turned on are measured and calculated as mean values expressed by the following Equations and (2) t2(n) t(n 6) t(n 7)(1 2 a. a.

a a C

C

t2(n) t(n6) t(n7) 2 After the time tl(f) required for the compressor being turned off and the time tl(n) required for the compressor being turned on are calculated by Equations and the spatial and circumstantial cooling loads are measured or evaluated by comparing the calculated times with the time values in Tables 1, 2 and 3 stored in the microcomputer.

The following Tables are intended to evaluate a circumstantial cooling load in the cooling load measuring step, and Table 1 is applied to a case when the air conditioner is installed in a "larger space" having a cooling load larger than the cooling capacity of the air conditioner, Table 2 is applied to a case when the air conditioner is installed in a "standard space" having a cooling load corresponding to the cooling capacity of the air conditioner, and Table 3 is applied to a case when the air conditioner is installed in a "smaller space" having a cooling load smaller than the cooling capacity of the air conditioner.

Table 1 r r r, r Set Temperature 26"C 27'C 28 C Circumferential Load Compressor Compressor Compressor Compressor Compressor Compressor Off Time On Time Off Time On Time Off Time On Time Small t26a-t26aa t26d-t26dd t27a-t27aa t27d-t27dd t28a-t28aa t28d -t28dd Medium t26b-t26bb t26e-t26ee t27b-t27bb t27e -t27ee t28b -t28bb t28e -t28ee Large t26c -t26cc t26f-t26ff t27c~t27cc t27f-t27ff t28c- t28cc t28f t28ff Table 2

I

r r r r r Set Temperature 26 C 27'C 28 C Circumferential Load Compressor Compressor Compressor Compressor Compressor Compressor Off Time On Time Off Time On Time Off Time On Time Small t26g-t26gg t26j-t26jj t27g-t27gg t2 7 j-t27jj t28g t28gg t28j t28jj Medium t26h *t26hh t26k -t26kk t27h-t27hh t27k t27kk t28h t28hh t28k t28kk Large t26i t26ii t261-t2611 t27i-t27ii t271-t2711 t28i-t28ii t281 t2811 Table 3 Set Temperature 26 0 C 27"C 28 C Circumferential Load Compressor Compressor Compressor Compressor Compressor Compressor Off Time On Time Off Time On Time Off Time On Time Small t26m-t26mm t26p-t26pp t27m-t27mm t27p-t27pp t28m t28mm t28p t28pp Medium t26n-t26nn t26q-t26qq t27n-t27nn t27q-t27qq t28n t28n t28q t28qq Large t26o-t26oo t26r-t26rr t27o-t27oo t27r-t27rr t28o t28oo t28r t28rr FIG. 5 shows a characteristic graph used when the cooling load is evaluated, and the graph shows variations in the room temperature when the air conditioner is operated at a set temperature of 26°C. Therefore, after the time tl(f) required for the S compressor being turned off and the time tl(n) required for the compressor being turned on are calculated, the spatial cooling load is evaluated as one of "larger space", "standard space" and "smaller space" and the circumferential cooling load is evaluated as one of "large", "medium", and "small" depending on the calculated times.

Since tl(f) is t26n t26nn and tl(n) is t26q t26qq as shown in FIG. 6 when the S air conditioner is operated as shown in FIG. 4, the spatial cooling load is evaluated as "smaller space" and the circumferential cooling load is evaluated as "medium".

Referring to the characteristic graph show in FIG. 6, when the air conditioner is installed in a space having a constant air volume, the operation time of the compressor varies with the magnitude of the circumstantial cooling load. For example, when the air conditioner is operated in a "smaller space" at a set temperature of 26°C, the on time tl(f) of the compressor becomes longer and the off time of the compressor becomes shorter when the circumstantial load becomes larger. When the circumstantial load is "large", the cooling time required for the air conditioner lowering the room temperature to a desired set temperature becomes longer, and once the compressor is turned off, since the room temperature rises quickly to a temperature at which compressor is operated again due to the large circumstantial cooling load, the off time of the compressor becomes short.

In general, the on condition of the compressor is a set temperature 0.5°C, and the off condition of the compressor is a set temperature 0.50C. Therefore, under a condition having the same spatial cooling load and the same circumstantial cooling load, when the set temperature is lower, the on time of the compressor is relatively longer. In this case, the off time of the compressor is nearly the same in the same space.

That is, when the set temperature is 260C, the compressor is off while the room temperature rises from 25.5°C to 26.50C, when the set temperature is 27C, the compressor is off while the room temperature rises from 26.5C to 27.5°C, and when the set temperature is 280C, the compressor is off while the room temperature rises Sfrom 27.5°C to 28.5°C. Therefore, in all cases the room temperature rises by 1 C, and the off times of the compressor are nearly the same.

In addition, under a condition having the same circumstantial cooling and the same set temperature, when the space is larger and therefore the spatial cooling load is larger, the time for which the compressor is on becomes longer and the time for which the compressor is off becomes shorter.

-i 11 1- 1 1 1 I ~r ?p ii)rh:::( Referring to the characteristic graph shown in FIG. 6, since ti is between t26n -t26nn and tl(n) is between t26q t26qq, the spatial coolin g load is evaluated as "1smaller space" and the circumstantial cooling load is evaluated as "medium".

Accordingly, in a first responding step of responding to the measured cooling loads, the S air conditioner is operated to respond to the conditions as shown in the following Table 4 and FIG. 7 Table 4 Circumstantial Load Set Temperature Air Blow Direction Air Blow Rate Small. 2600 00 PO~ Low (Weak) Medium 2700 a 0 Medium (Medium) *Large 2800 00O 150 High (Strong) That is, in order to respond to the evaluated conditions, the air conditioner is operated in a state in which the set temperature is controlled to be 27 0 C according to the step of controlling a room temperature, the vertical air blow direction is controlled to be a 0 according to the step of controlling an air blow direction, and the air blow rate is controlled to be "medium" according to the step of controlling an air blow rate. In order to respond to the varying cooling load, that is, in order to maintain comfortable air conditioning and reduce the power consumption of the air conditioner, the air conditioner is controlled in a responsive manner.

Now, the first responding step of responding to the measured cooling loads according to circumstantial cooling loads in a room having a constant spatial cooling load will be described briefly.

First, when the circumstantial cooling load is "small", when the set temperature is set to be 26 0 C, the vertical air blow direction is a 0 P30 and the air blow rate is in the 18 ~-u "weak" mode, the air flow speed is 0.2 m/sec in the residing range of the user. When this is converted into a PMV value, the PMV value is about -0.06 and means that it is not too cool or warm, it is comfortable. That is, since the circumstantial cooling load is small, a comfortable room condition can be maintained when the air conditioner is operated at a set temperature of 26'C while the air blow direction and air blow rate is controlled as above. At this time, as other factors of the PMV, the relative humidity is RH, the radiation temperature is the same as the room temperature, the amount of activity of a dweller is 1.0 met the same as in case of reading, and the amount of clothing of the dweller is 0.6 dclo in case of general summer clothing.

Second, when the circumstantial cooling load is "medium", when the set temperature is set to be 270C, the vertical air blow direction is cxo, and the air blow rate is "medium", the air flow speed is 0.6 m/sec in the residing range of the user. When this is converted into a PMV value, the PMV value is about 0.05 and means that it is not too cool or warm, it is comfortable. That is, since a comfortable room condition can S be maintained and the room temperature is not lowered unnecessarily when the air conditioner is operated at a set temperature of 270C according to the circumstantial cooling load while the air blow direction and air blow rate is controlled as above, the energy consumption of the air conditioner can be reduced.

**Third, when the circumstantial cooling load is "large", when the set temperature 2G is set to be 28°C, the vertical air blow direction is and the air blow rate is "strong", the air flow speed is 1.1 m/sec in the residing range of the user. When this is converted into a PMV value, the PMV value is about 0.36 and means that it is not too cool or warm, it is comfortable. That is, since a comfortable room condition can be maintained and the room temperature is not lowered unnecessarily when the air 19 conditioner is operated at a set temperature of 28'C according to the "large" circumstantial cooling load while the air blow direction and air bl ow rate is controlled as above, the energy consumption of the air conditioner can be reduced.

In the first responding step of responding to the measured cooling loads, the set temperature and air blow rate are controlled in accordance with the spatial and circumstantial loads, and in the step of checking a period of cooling time, the cooling operation time is checked while reaching the predetermined period of time ta after the time t(nO) which is the starting point of the first measuring step of measuring cooling loads. When the cooling operation time is greater than the predetermined period of time ta, a second measuring step of measuring cooling loads begins.

When the predetermined period of time ta has passed while the air conditioner is operated according to the first measuring step of measuring cooling loads and the first responding step of responding to the measured cooling loads, the circumstantial cooling load is measured again. Since the circumferential cooling load may be changed during the cooling operation, the circumstantial cooling load is measured again, and when the circumferential cooling load is changed, a new responding cooling operation is required to meet the changed circumferential cooling load. At this time, since the air conditioner is in the same space, there is no change in the spatial cooling load and the spatial cooling load measured in the first measuring step of measuring cooling loads is used.

As shown in FIGS. 3 and 4, in the second measuring step of measuring cooling loads, the periods of time from the time when the compressor is turned off first time after the predetermined period of cooling time ta has passed to the times when the compressor is turned on twice and turned off twice are measured, respectively. Then.

77777,, after the times required for the compressor being turned on and turned off are calculated, respectively from the measured time value, the mean time values are calculated in the microcomputer.

For example, if the predetermined period of time ta has passed before the point in FIG. 4, the times required for the compressor being turned on are t(f6) and t(f7), and the times required for the compressor being turned off are t(n6) and t(n7).

Therefore, the mean time t2(f) required for the compressor being turned off and the mean time t2(n) required for the compressor being turned on are calculated by the following Equations and (4) t2(n) t(n6) t(n7) 2 (3) t2(n) t(n6) t(n7) t2(n) (4) 2 The circumstantial cooling load is measured by comparing t2(f) and t2(n) calculated by Equations and and the time values in Tables 1, 2 and 3 stored in the microcomputer.

As in the example shown in FIG. 4, in a second responding step of responding to the measured cooling loads, the air conditioner is operated so as to respond to the 5 measured loads in a state in which the set temperature is controlled to be 272C, the vertical air blow direction is controlled to be and the air blow rate is controlled to be "medium" after confirming the spatial cooling load is "smaller space" and the 21 circumferential cooling load is "medium". When the predetermined period of time ta has passed after the responsive operation begins, the measu ring step of measuring cooling loads is performed again while the air condition is operated at a set temperature of 27'C.

If the circumferential cooling load is changed from "medium" to "large" during the cooling operation, t2(f) and t2(n) which are measured in the second measuring step of measuring cooling loads fall into another range in FIG. 6. That is, it can be found that though the air conditioner is operated, for responding to the measured cooling loads, in conditions in which the spatial cooling load is "smaller space" and the set temperature is 2700, the range of the circumstantial cooling load is changed in the characteristic diagram when the circumstantial cooling load is changed from "medium" to "large".

In other words, since t2(f) calculated by Equations 3 and 4 falls between t27o and t27oo, and t2(n) falls between t27r and t27rr, the spatial cooling load is "smaller space", and therefore the circumstantial cooling load is decided as "large".

Since the spatial cooling load is decided as "smaller space" and the circumstantial cooling load is decided as "large" according to the calculated t2(f) and t2(n), in the second responding step of responding to the measured cooling load the responsive operation is performed according to corresponding conditions in Table 4 and.

FIG. 7.

That is, the responsive operation is performed in conditions which the set too* .0.0 temperature is controlled to be 280C according to the step of controlling a room temperature, the vertical air blow direction is controlled to be a 0 3 according to the step of controlling an air blow direction, and the air blow rate is controlled to be "strong" 22 according to the step of controlling an air blow rate. In order to respond to the varying cooling load, that is, in order to maintain comfortable air conditioning and reduce the power consumption of the air conditioner, the air conditioner is controlled in a responsive manner.

Since the room temperature is controlled to be 2600, 27'C or 28'C during the cooling operation according to the first and second responding steps of responding to the measured cooling loads, the dweller who is exposed to the cooled conditions for a considerable time begins to feel cold. Therefore, it is necessary that the room temperature is controlled based on the times of respective room temperatures until then so that the dweller does not feel cold.

FIG. 10 shows a graph of reference time concerning the conditions beyond the adaptability of a human body. Referring to FIG. 10, the graph means that a human body feels cold when the room temperature is controlled to be 260C for more than a period of time tx, or when the room temperature is controlled to be 2700 for more than 14 a period of time ty. Of course, similarly, a human body begins to feel cold when the :0,00 room temperature is controlled to be 2800 for more than a period of time tz, the periods 00 of time tx, ty and tz are result values of an experiment in which times when ordinary healthy persons begin to feel cold are measured at various temperatures.

That is, when the room temperature is controlled to be 260C for more than a.

period of time tx, when the room temperature is controlled to be 2700 for more than a period of time ty, or when the room temperature is controlled to be 28'C for more than period of time tz, the step of responding to the condition beyond thle adaptability of a human body begins.

23 Here, a method of calculating times t(26 0 t(27 0 C) and t(28 0 C) for deciding whether a condition beyond the adaptability of a human body occurs at respective temperatures is shown in Table 5 and FIG. 8, and Table 6 and FIG. 9. The method of calculating times for deciding whether a condition beyond the adaptability of a human body occurs is performed in two major manners, and one is applied to a case in which the room temperature rises without falling during the operation of responding to cooling loads and the other is applied to a case including at least one interval in which the room temperature falls.

The following Table 5 and FIG. 8 show the former case, and Table 6 and FIG.

9 show the latter case. Table 5 shows the result times for deciding whether a condition beyond the adaptability of a human body occurs, which are calculated from the case shown in FIG. 8, and Table 6 shows the result times for deciding whether a condition beyond the adaptability o f a human body occurs, which are calculated from the case shown in FIG. 9.

ei In the former case in which the room temperature rises without falling during the operation of responding to cooling loads, times for deciding whether a condition beyond the adaptability of a human body occurs are calculated with reference to FIG. 8 and 6 0 Table 5. That is, when the circumferential cooling load is not changed or is increased "00:.0 during the operation of responding to cooling loads, times t(26 0 t(27 0 C) and t(280) for deciding whether a condition beyond the adaptability of a human body occurs are .00. calculated as shown in Table 5. If the room temperature is not changed at the points 000. of time Hi, H2 and H3 when the cotrolled room temperatures until the point of time are 0 checked by the microcomputer, the continued time of the temperature is calculated.

24 S- Table Control Pattern Hi H2 H3 t(26'C)=tl +t2+t3 t(26-C)=O t:(26'C)=O 1 t(27 0 0)=O t(27-C)=t4 t(27 0

C)=O

t(28 0 C)=O t(28 0 C)=O t(28 0 t(26'C)=O t(26'C)=O t(26 0

C)=O

2 t(27 0 C)=t2+t3 t(27 0 C)=O t(27 0

C)=O

t(28 0 C)=O t(28-C)=t4 t(28 0 t(26 0 C)=O t(26-C)=O t(26 0

C)=O

3 t(27 0 0)=O t(27 t(27 0 0)=O t(28 0 C)=t3 t(28 0 C)=t3+t4 t(28*C )=t3+t4+t5 t(26 0 0)=O t(26 0 C)=O t(26 0

C)=O

4 t(27 0 0)=O t(27 0 C)=t4 t(27 0 0)=O t(28 0 C)=t2+t3 t(28-C)=t2+t3+t4 t(28 0 C)=t2+t3+t4+t5 t(26 0 0)=O t(26 0 C)=O t(26 0

C)=O

t(27 0 C)=t3 t(27 0 C)=O t(27-C)=O 0 C)=O t(28 0 C)=t4 t(28 0 0)=t4+t5 t(26 0 C)=O t(26 0 C)=O t(26 0

C)=O

6 t(27 0 C)=O t(27 0 C)=O t(27 0

C)=O

0 C)=t3 t(28 0 C)=t3+t4 t(28 0 C)=t3+t4+t5

I

a *1 On the other hand, when the room temperature rises even in the step of responding to cooling loads, the room temperature before the room temperature rises has almost no influence on making a human body feel cold, and the human body is more affected by the elevated room temperature. Therefore, when the room temperature rises, the room temperatures before the room temperature rises are reset and the continued time of the room temperature after the room temperature rises are calculated and stored in the computer.

-0 i, 7,'Z ,7,,7 For example, when the operation of responding to cooling loads is performed according to pattern 3 of FIG. 8, in the step of responding to the condition beyond the adaptability of a human body, times at the points of time H1, H2 and H3 for deciding whether a condition beyond the adaptability of a human body occurs can be found as follows.

According to pattern 3, the air conditioner is operated at a set temperature of 26C in the first measuring step of measuring cooling loads, operated at a set temperature of 270C in the first responding step of responding to the cooling loads and the second measuring step of measuring cooling loads and operated at a set temperature of 280C in the second responding step of responding to the cooling loads.

Therefore, times for deciding whether a condition beyond the adaptability of a human body occurs are found as shown in Table That is, at the first point of time H1 for deciding whether a condition beyond the S adaptability of a human body occurs, time t(26 0 C at 260C for deciding whether a °s condition beyond the adaptability of a human body occurs is time t(27°C at 27'C for deciding whether a condition beyond the adaptability of a human body occurs is "0" and time t(28 0 C at 280C for deciding whether a condition beyond the adaptability of a human body occurs is "t3".

In addition, at the second point of time H2 for deciding whether a condition beyond the adaptability of a human body occurs, time t(26°C at 260C for deciding .whether a condition beyond the adaptability of a human body occurs is time t(27C at 270C for deciding whether a condition beyond the adaptability of a human body occurs is and time t(28 0 C at 28°C for deciding whether a condition beyond the adaptability of a human body occurs is "t3 t4".

26 n 471j z At the third point of time H3 for deciding whether a condition beyond the adaptability of a human body occurs, time t(26 0 C at 26°C for deciding whether a condition beyond the adaptability of a human body occurs is time t(27 0 C at 27"C for deciding whether a condition beyond the adaptability of a human body occurs is and time t(28 0 C at 28°C for deciding whether a condition beyond the adaptability of a human body occurs is "t3 +t4 In the step of deciding whether a condition beyond the adaptability of a human body occurs, at the point of time H1 for the computer deciding whether a condition beyond the adaptability of a human body occurs, since t(26°C) is t(27°C) is and t(28"C) is the operation for responding to the condition beyond the adaptability of a human body is performed or the operation for responding to cooling loads is continued.

That is, when t(28 0 C) is longer than reference time tz at 28°C for deciding whether a condition beyond the adaptability of a human body occurs, the step of responding to the condition beyond the adaptability of a human body begins to control the room temperature, vertical air blow direction, horizontal air blow direction and air S blow rate, and when t(28 0 C) is shorter than or the same as reference time tz at 28 C for deciding whether a condition beyond the adaptability of a human body occurs, the step of responding to cooling loads is continued.

At other points of time H2, H3, etc. for the computer deciding whether a condition S beyond the adaptability of a human body occurs, similarly the operation for responding to cooling loads is continued or the operation for responding to the condition beyond the adaptability of a human body is performed until a stop signal or a signal to stop the operation of responding to cooling loads.

27 C. Table 6 Control Pattern H,

H

2 H 3 t(26°C)=t3 t(26°C)=0 t(26"C)=0 7 t(27°C)=t2 t(27"C)=t2+t4 t(27 0

C)=O

t(28°C)=O t(28 0 C)=O t(28°C)=t5 t(26°C)=0 t(26 0 C)=0 t(26oC)=0 8 t(27°C)=t3 t(27 0 C)=0 t(270C)=0 t(28°C)=t2 t(28 C)=t2+t4 t(280C)=t2+t4+t5 t(26°C)=t3 t(26 C)=0 t(26°C)=0 9 t(27 0 C)=0 t(27"C)=t4 t(27oC)=0 t(28°C)=t2 t(28 C)=t2 t(28°C)=t5 The latter case includes control patterns of cases including at least one interval in which the room temperature falls during the operation for responding to cooling loads, times for deciding whether a condition beyond the adaptability of a human body occurs are calculated with reference to FIG. 9 and Table 6.

In other words, when the circumferential cooling load is decreased at least once during the operation of responding to cooling loads as shown in FIG. 9, times t(26'C), t(27 0 C) and t(28°C) for deciding whether a condition beyond the adaptability of a human body occurs are calculated as shown in Table 6. That is, if the room temperature is not changed at the points of time when the cotrolled room temperatures until the point of time are checked by the microcomputer, the continued time of the room temperature is calculated continuously, but when the room temperature rises, the room temperatures before the room temperature rises are reset and the continued time of the room temperature after the room temperature rises are calculated and stored in the computer. If the room temperature falls, times of the respective room temperatures 28 before the room temperature falls are stored in the microcomputer and the continued time of the lowered room temperature is calculated continuously.

If the room temperature falls, it is natural that the lowered room temperature has influence on making a human body feel cold. In addition, since the room temperatures before the room temperature falls have had influence on making the human body feel cold but the influence is neither offset nor considered in the next step, the times of the respective room temperatures are added to times of respective temperatures for deciding whether a condition beyond the adaptability of a human body occurs and the results are stored in the: micro computer.

For example, when the operation of responding to cooling loads is performed according to pattern 7 of FIG. 9, in the step of responding to the condition beyond the adaptability of a human body, times at the points of time H1, H2 and H3 for deciding whether a condition beyond the adaptability of a human body occurs can be calculated as shown in Table 6.

e OAccording to pattern 7 as shown in FIG. 9, the air conditioner is operated at a set temperature of 26°C in the first measuring step of measuring cooling loads, operated at a set temperature of 270C in the first responding step of responding to the cooling .loads and the second measuring step of measuring cooling loads and operated at a set temperature of 260C in the second responding step of responding to the cooling loads.

Therefore, at the first point of time H1 for deciding whether a condition beyond the adaptability of a human body occurs, t(26 0 C is t(27 0 C is and t(28C is In addition, at the second point of time H2 for deciding whether a condition beyond the adaptability of a human body occurs, t(26 0 C is t(27°C is "t2+t4", and 29 II_ rvi-;ti" rlslr I r I, r~ll~ i~i"L~ 1- II t(28"C is At the third point of time H3 for deciding whether a condition beyond the adaptability of a human body occurs, t(26°C is t(27 0 C is and t(28 0 C is In the step of deciding whether a condition beyond the adaptability of a human body occurs, at the first point of time H1 for the computer deciding whether a condition beyond the adaptability of a human body occurs, since t(26°C) is t(27°C) is "t2" and t(28'C) is when "t3" is longer than reference time tx at 26 0 C for deciding whether a condition beyond the adaptability of a human body occurs, the step of responding to the condition beyond the adaptability of a human body begins to control the room temperature, vertical air blow direction, horizontal air blow direction and air blow rate, and when "t3" is shorter than or the same as reference time tx, the step of responding to cooling loads is continued.

Here, since the cooling time is controlled so that "t2" which is t(27°C) at 27°C for deciding whether a condition beyond the adaptability of a human body occurs is always smaller than reference time ty for deciding whether a condition beyond the adaptability of a human body occurs, a case in which "t3" is larger than tx and a case in which "t2" is larger than ty cannot occur concurrently.

At other points of time H2, H3, etc. for the computer deciding whether a condition beyond the adaptability of a human body occurs, similarly the operation for responding to cooling loads is continued or the operation for responding to the condition beyond the 20 adaptability of a human body is performed until a stop signal or a signal to stop the operation of responding to cooling loads.

In the step of responding to cooling loads and the step of deciding whether a condition beyond the adaptability of a human body occurs, when t(26 0 C) tx, t(27''C) n >ty, or t(28 t tz, the step of responding to the condition beyond the adaptability of a human body is performed as the following Table 7.

That is, at the point when t(26 0 0) is larger than tx during the operation of a set temperature of 260C, the air conditioner is operated in a state in which the set temperature is raised by 1 00 and is controlled to be 27CC according to the step of controlling a room temperature, the vertical air blow direction is controlled to be a P" according to the step of controlling an air blow direction, the horizontal air blow direction is controlled to rotate from side to side within a predetermined angle and the air blow rate is controlled to be in the "weak" mode according to the step of controlling I C an air blow rate.

Table 7

S

Sc

S

S. S

S

Vertical Horizontal Air Room Operation state Temperature Air Blow Air Blow Blow Temperature Set Direction Direction Rate 2600 Cooling 2700 a. 130 Rotating from Weak side to side 270C Cooling 2800 ao+ 13" Rotating from Weak side to side 2800C Cooling Rotating from Weak after Time(h) 2800 ca. [30 side to side __________Compressor Off In addition, while the room temperature is controlled at a set temperature of 27-'C, at the time when t(27 0 C) is larger than ty, the air conditioner is operated in a state in which the set temperature is raised by 1 'C and is controlled to be 27'C, the 31 vertical air blow direction is controlled to be a 0 the horizontal air blow direction is controlled to rotate from side to side within a predetermined angle and the air blow rate is controlled to be in the "weak" mode. In addition, while the room temperature is controlled and operated at a set temperature of 28 0 C, at the time when t(28 0 C) is larger than tz, the air conditioner is controlled at a set temperature of 2800 after the compressor is stopped for time(h), and is operated in a state in which the set temperature is raised by 1 00 and is controlled to be 2700, the vertical air blow direction is controlled to be ca 0 V3~ the horizontal air blow direction is controlled to rotate from side to side within a predetermined angle and the air blow rate is controlled to be in the I weak" mode. The air conditioner is similarly controlled and operated until a stop signal or a signal to stop the operation of responding to cooling loads.

FIG. 11 is a block diagram of an air conditioner employed in the present invention.

Referring to FIG. 11, after a room temperature sensing portion 51 measures the temperature of room air sucked into an air condition by using a temperature sensor, the room temperature sensing portion 51 transfers a signal corresponding to the sensed 5 temperature to a microcomputer 50. A compressor operating time detecting portion 53 detects operation time and pause time of the compressor and transfers the detected information to the microcomputer 50, and a cooling time checking portion 54 checks C- cooling times and transfers the information to the microcomputer 50. In addition, a time checking portion 52 for checking times used for deciding whether a condition beyond the adaptability of a human body occurs checks the times and transfers the information to the microcomputer 50 so that the microcomputer 50 can operate the air conditioner to respond to the condition beyond the adaptability of a human body.

32 An indoor fan driving portion 55 controls the output of an indoor fan 56 according to the control of the microcomputer 50 so as to control an air blow rate. A horizontal vane driving portion 57 controls horizontal vanes 57' so as to adjust a vertical air blow direction, and vertical vane driving portion 58 controls vertical vanes 58' so as to adjUlSt a horizontal air blow direction. In addition, a compressor driving portion 59 controls the operation of a compressor 60 so that the room temperature can reach a set temperature instructed by the microcomputer.

The method of controlling an air conditioner as described above according to the present invention controls the set temperature, air blow direction and air blow rate of the air conditioner so that an air conditioner can immediately respond to variations in cooling loads, and therefore provides advantages in which comfortable air conditioning can be established, energy can be saved, and a sickness due to air conditioning can be prevented by preventing excessive cooling.

That is, the method of the present invention controls the air blow rate and air blow direction when the cooling loads become high so that a PMVV value falls between 0.5 and +0.5 and therefore the room temperature is maintained in a neither too warm nor too cool condition, and, in addition, prevents the air conditioner from operating at an unnecessarily low temperature by reasonably raising the set temperature so that power consumption can be reduced. On the other hand, the method controls the air blow rate and air blow direction when the cooling loads become low so that a PMV value falls between -0.5 and +0.5 and therefore the room temperature is maintained in a comfortable condition, and, in addition, prevents the air conditioner from operating at an unnecessarily low temperature by setting the set temperature to be suitable for 33 the low cooling load so that excessive cooling can be prevented and therefore a sickness due to air conditioning can be prevented.

34

Claims

1. A method of controlling an air conditioner incluaing the steps of: measuring cooling loads by detecting periods of time for which a compressor is on and periods of time for which the compressor is off while operating the air conditioner for a predetermined time in predetermined cooling conditions and comparing the detected periods of time with reference time values determined in advance; and responding to the measured cooling loads by changing a set temperature of the air conditioner and simultaneously changing at least one of the blow direction and blow rate of cooled air discharged from the air conditioner so that comfortable air conditioning can be attained according to the cooling load measured in the step of measuring cooling loads.

S2. The method of controlling an air conditioner as claimed in claim 1, wherein the step of measuring cooling loads comprising the steps of: detecting times when the compressor is turned on and tuned off after operating the air conditioner in predetermined cooling conditions including a constant set temperature, and predetermined air flow rate and predetermined air blow direction; and. measuring spatial and circumstantial loads by comparing the times for which tme compressor is on and off with reference time values preset in advance. a o•

3. The method of controlling an air conditioner as claimed in claim 1, wherein the step of responding to the measured cooling loads comprising the steps of: rr~ i- l i-r i; i li-~ u"r-i ~in~ h~i ~i lr- controlling a room temperature by changing the set cooling temperature according to the cooling loads measured in the step of measuring cooling loads; controlling a vertical air blow direction discharged from the air conditioner in connection with the set temperature controlled according to the step of controlling a room temperature; and controlling a blow rate of cooled air in connection with the vertical air blow direction controlled by the step of controlling a vertical air blow direction.

4. The method of controlling an air conditioner as claimed in claim 1, wherein the method further includes the step of checking a period of cooling time from the step of measuring cooling loads to the step of responding to the measured cooling loads and deciding to restart the step of measuring cooling loads at a predetermined interval.

A method of controlling an air conditioner including the steps of: .detecting operation times of an air conditioner operating at a predetermined set o* temperature after operating the air conditioner for a predetermined time in aoo° S predetermined cooling conditions; deciding whether a condition beyond the adaptability of a human body occurs by comparing the operation times detected in the step of detecting operation times with. time values of respective temperatures stored in a microcomputer for deciding whether a condition beyond the adaptability of a human body occurs; and responding to the condition beyond the adaptability of a human body by changing a set temperature of the air conditioner and simultaneously changing at least 36 71"~ :l one of the blow direction and blow rate of cooled air discharged from the air conditioner according to the deciding conditions.

6. The method of controlling an air conditioner as claimed in claim 5, wherein the step of deciding whether a condition beyond the adaptability of a human body occurs includes the step of deciding that the room temperature is "cold" when any one of the summed operation times at respective temperatures during cooling operation until this step begins is longer than the time values stored in the microcomputer, and deciding to respond to the condition beyond the adaptability of a human body.

7. The method of controlling an air conditioner as claimed in claim 5, wherein the step of deciding whether a condition beyond the adaptability of a human body occurs includes the step of deciding the operation time at one temperature by taking the operation time at the elevated temperature without considering the operation time data of the same temperature before the temperature is reached when the room temperature rises without falling, and deciding the operation time at one temperature by summing l the operation times at the temperature until this step begins when the room temperature :falls.

8. The method of controlling an air conditioner as claimed in claim 5, wherein the steps of responding to the condition beyond the adaptability of a human body comprises the steps of: changing the set temperature so that the room temperature may become comfortable for a human body; 37 controlling the vertical blow direction of cooled air discharged from the air conditioner upward by a predetermined degree so that the human body does not feel cold: changing the horizontal direction of cooled air blow discharged from the air conditioner from side to side periodically; and controlling the air blow rate so that the air blow rate is low or in the "weak" mode.

9. The method of controlling an air conditioner as claimed in claim 8, wherein in the step of changing the set temperature, the set temperature can be changed within a predetermined range having an upper limit value and a lower limit value.

The method of controlling an air conditioner as claimed in claim 9, wherein in the step of changing the set temperature, when the room temperature is controlled by the upper limit value, the operation of a compressor is stopped for a predetermined time at the point of time when the summed operation time corresponding to the upper limit value is larger than the reference time stored in the microcomputer corresponding to the upper limit value for deciding whether a condition beyond the adaptability of a human body occurs Se*

11. A method of controlling an air conditioner comprises the steps of: measuring cooling loads by detecting times for which a compressor is on and a times for which the compressor is off while operating the air conditioner for a predetermined time in predetermined cooling conditions; 38 responding to the measured cooling loads by changing a set temperature of the air conditioner and simultaneously changing the blow direction and blow rate of cooled air discharged from the air conditioner; deciding whether a condition beyond the adaptability of a human body occurs by comparing the operation times at respective temperatures according to the step of measuring an operation time with time values of respective temperatures stored in a microcomputer for deciding whether a condition beyond the adaptability of a human body occurs; and responding to the condition beyond the adaptability of a human body by changing a set temperature of the air conditioner and simultaneously changing the blow direction and blow rate of cooled air discharged from the air conditioner according to the deciding conditions.

12. A method of controlling an air conditioner including the steps substantially as hereinbefore described. DATED: 2 June 1999 CARTER SMITH BEADLE Patent Attorneys for the Applicant: LG ELECTRONICS INC. 0 egO go DCC:TMP:#31534.CLA 2 June 1999 I