Air conditioning system having a plurality of indoor units

Claim 2

An air conditioning system comprising: a variable capacity energy source for providing working fluid at variable energy levels in response to a signal applied thereto; a plurality of delivery means for delivery of said working fluid to separate spaces for air conditioning the respective spaces; working fluid control means provided in said delivery means for controlling the amount of working fluid supplied therethrough in response to a signal applied thereto; a plurality of temperature setting devices for setting reference temperatures respectively for said spaces; a plurality of temperature detectors for measuring the temperature of the respective spaces; and a central control unit including means for setting a plurality of temperature zones in response to said reference temperatures respectively for said spaces, means for detecting to which one of said temperature zones each of said measured temperatures belongs, means for detecting the temperature gradient of each of said measured temperatures, and means for generating a control signal based on said detected temperature gradient and said detected temperature zone and applying said control signal to one or both of said working fluid control means and said energy source.

Claim 3

An air conditioning system as claimed in claim 1, wherein said working fluid control means comprises a plurality of fluid control means respectively provided in said plurality of delivery means for controlling the respective fluids passing through said delivery means.

Claim 4

An air conditioning system as claimed in claim 2, wherein said control unit includes means for sampling said measured temperatures successively at periodic intervals, means for storing the corresponding value of each of the sampled temperatures and means for comparing the stored temperature value with said sampled temperature value which occurs subsequent to said stored temperature value to determine whether each of said temperature is on the increase or decrease.

Claim 5

An air conditioning system as claimed in claim 3, further comprising means for synchronizing said sampling means with the application of said control signal to said fluid control means so that the interval between successive sampling events commences in response to said control signal.

Claim 6

An air conditioning system as claimed in claim 2, wherein said system is operable as a cooling system, further comprising means for closing an associated one of said fluid control means when said detected temperature zone is below a preset temperature or opening an associated one of said fluid control means when said detected temperature zone is higher than said preset temperature by a certain temperature value.

Claim 7

An air conditioning system as claimed in claim 2, wherein said system is operable as a heating system, further comprising means for closing an associated one of said fluid control means when said detected temperature zone is higher than a preset temperature by a certain temperature value or opening an associated one of said fluid control means when said detected temperature zone is below said preset temperature.

Claim 8

An air conditioning system as claimed in claim 2 or 3, wherein said system is operable as a cooling system, wherein said central control unit includes means for defining a first temperature zone which lies in a range below a first preset temperature corresponding to a user's setting value, a second temperature zone which lies in a range between said first preset temperature and a second preset temperature corresponding to a decision making point, a third temperature zone which lies in a range between said second preset temperature and a third preset temperature, and a fourth temperature zone which lies in a range above said third preset temperature, means for detecting to which one of said first, second, third and fourth temperature zones each said measured temperature belongs, means for generating a control signal for de-energizing said energy source when each said measured temperature is detected as belonging to said first zone and for opening an associated one of said fluid control means when each said measured temperature is detected as belonging to said fourth zone.

Claim 9

An air conditioning system as claimed in claim 7, wherein said gradient detecting means includes means for detecting whether each of said measured temperatures has a non-negative gradient when each said temperature is not increasing as a function of time or a negative gradient when each said temperature is decreasing as a function of time, and wherein said control signal generating means further comprises: means for generating a fluid control signal when one of said measured temperatures is detected as having a non-negative temperature gradient and as belonging to said third or fourth temperature zone and another one of said measured temperatures is detected as having a negative temperature gradient and as belonging to said second temperature zone, said fluid control signal being applied to one of said fluid control means for decreasing the amount of working fluid passing therethrough, said one of said fluid control means being associated with the space in which said another one of said measured temperatures is detected.

Claim 10

An air conditioning system as claimed in claim 7, wherein said control signal generating means further comprises means for generating an energy level control signal when one of said measured temperatures is detected as having a non-negative temperature gradient and as belonging to said third or fourth temperature zone and another one of said measured temperatures is detected as having either one of said temperature gradients and as belonging to said third or fourth temperature zone or detected as having a non-negative temperature gradient and as belonging to said second temperature zone, said energy level control signal being applied to said energy source to increase its energy level.

Claim 11

An air conditioning system as claimed in claim 7, wherein said control signal generating means further comprises means for generating a second energy level control signal when all of said measured temperatures are detected as having a negative temperature gradient and as belonging to said second temperature zone, said second energy level control signal being applied to said energy source to decrease its energy level.

Claim 12

An air conditioning system as claimed in claim 2 or 3, wherein said system is operable as a heating system, and wherein said central control unit includes means for defining a first temperature zone which lies in a range above a first preset temperature corresponding to a user's setting value, a second temperature zone which lies in a range between said first preset temperature and a second preset temperature corresponding to a decision making point, a third temperature zone which lies in a range between said second preset temperature and a third preset temperature, and a fourth temperature zone which lies in a range below said third preset temperature, means for detecting to which one of said first, second, third and fourth temperature zones each of said measured temperature values belongs, means for generating a control signal for de-energizing said energy source when said each said measured temperature value is determined as belonging to said first temperature zone and for opening an associated one of said fluid control means when each of said measured temperature values is detected as belonging to said fourth temperature zone.

Claim 13

An air conditioning system as claimed in claim 11, wherein said gradient detecting means includes means for detecting whether each of said measured temperatures has a positive gradient when each said temperature is increasing as a function of time or a non-positive gradient when each said temperature is not increasing as a function of time, and wherein said control signal generating means further comprises means for generating a fluid control signal when one of said measured temperatures is detected as having a non-positive temperature gradient and as belonging to said third or fourth temperature zone and another one of said measured temperatures is detected as having a positive temperature gradient and as belonging to said second temperature zone, said fluid control signal being applied to one of said fluid means for decreasing the amount of working fluid passing therethrough, said one of said fluid control means being associated with the space in which said another one of said measured temperatures is detected.

Claim 14

An air conditioning system as claimed in claim 11, wherein said control signal generating means further comprises means for generating an energy level control signal when one of said measured temperatures is detected as having a non-positive temperature gradient and as belonging to said third or fourth temperature zone and another one of said measured temperatures is detected as having either one of said temperature gradient and as belonging to said third or fourth zone or detected as having a non-positive temperature gradient and as belonging to said second temperature zone, said energy level control signal being applied to said energy source for increasing its energy level.

Claim 15

An air conditioning system as claimed in claim 11, wherein said control signal generating means further comprises means for generating a second energy level control signal when all of said measured temperatures are detected as having a positive temperature gradient and as belonging to said second temperature zone, said second energy level control signal being applied to said energy source for decreasing its energy level.

Claim 16

An air conditioning system as claimed in claim 1, wherein said energy source comprises a compressor and a variable speed electric motor for driving said compressor at a variable speed.

Claim 17

An air conditioning system as claimed in claim 15, wherein said electric motor is of a type which is continuously variable in speed.

Claim 18

An air conditioning system as claimed in claim 1 or 3, wherein said system is operable as a cooling system, and wherein said central control unit comprises means for detecting whether each of said measured temperatures is above or below a predetermined temperature level, means for determining whether each of the measured temperatures is not decreasing or decreasing as a function of time, means for generating a control signal when one of said measured temperatures is detected as increasing in a range above said predetermined temperature level and another one of said measured temperatures is detected as decreasing in a range below said predetermined temperature level and applying said control signal to the valve means associated with the space in which said another one of said measured temperatures is detected.

Claim 19

An air conditioning system as claimed in claim 17, wherein said control unit further comprises means for generating an energy level control signal when one of said measured temperatures is detected as not decreasing in a range above said predetermined temperature level and another one of said measured temperatures is detected as either not decreasing or decreasing in a range above said predetermined temperature level or detected as not decreasing in a range below said predetermined temperature level, said energy level control signal being applied to said energy source for increasing its energy level.

Claim 20

An air conditioning system as claimed in claim 17, wherein said control unit further comprises means for generating a second energy level control signal when all of said measured temperatures are detected as decreasing in a range below said predetermined temperature level, said second energy level control signal being applied to said energy source for decreasing its energy level.

Claim 21

An air conditioning system as claimed in claim 1 or 3, wherein said system is operable as a heating system, and wherein said central control unit comprises means for detecting whether each of said measured temperatures is above or below a predetermined temperature level, means for determining whether each of the measured temperatures is increasing or not increasing as a function of time, means for generating a control signal when one of said measured temperatures is detected as decreasing in a range below said predetermined temperature level and another one of said measured temperatures is detected as increasing in a range above said predetermined temperature level and applying said control signal to the fluid control means associated with the space in which said another one of said measured temperatures is detected.

Claim 22

An air conditioning system as claimed in claim 20, wherein said control unit further comprises means for generating an energy level control signal when one of said measured temperatures is detected as decreasing in a range below said predetermined temperature level and another one of said measured temperatures is detected as either increasing or not increasing in a range below said predetermined temperature level or detected as not increasing in a range above said predetermined temperature level, said energy level control signal being applied to said energy source for increasing its energy level.

Claim 23

An air conditioning system as claimed in claim 21, wherein said control unit further comprises means for generating a second energy level control signal when all of said measured temperatures are detected as increasing in a range above said predetermined temperature level, said second energy level control signal being applied to said energy source for decreasing its energy level.

Claim 24

An air conditioning system as claimed in claim 1, wherein said temperature gradient detecting means comprises: a pair of sample-and-hold circuits; means for alternately causing said sampled-and-hold circuits at periodic intervals to receive a signal from a respective one of said temperature detectors; and a comparator for comparing output signals from said sample-and-hold circuits to generate a bi-level signal.

Claim 27

A method as claimed in claim 24, further comprising: (14) generating an energy level control signal if said data "1" is not present in step (12) for controlling said energy source to increase its capacity.

Claim 28

A method as claimed in claim 25, further comprising the steps of: (15) if said data "1" is not present in step (11), checking to see if the number of said data "1" stored in step (8) is equal to the number of said rooms; and (16) generating a second energy level control signal if said numbers are equal to each other for controlling said energy source to decrease its capacity.

Claim 29

A method as claimed in claim 24, 25 or 26, further comprising the steps of: (17) storing a data representing a lower limit temperature below said predetermined temperature and a data representing an upper limit temperature above said predetermined temperature with respect to each said room; (18) comparing each said most recent temperature data generated in step (2) with said lower limit temperature data; (19) if each said most recent temperature data is smaller than said lower limit temperature data, checking to see if one of said valves is in the open or closed condition; (20) storing a data "0" if said one of said valves in in the open condition in step (19); (21) if each said most recent temperature data is greater than said lower limit temperature data, comparing each said most recent temperature data with said upper limit temperature data; (22) if each said most recent temperature data is greater than said upper limit temperature data, checking to see if said one of said valves is in the open or closed condition; (23) storing a data "1" if said one of said valves is in the closed condition in step (22); (24) if said one of said valves is in the closed condition in step (19) or (22), or if each said most recent temperature data is not greater than said upper limit data compared in step (21), or in response to step (20) or (23), repeating steps (1), (2), (17) to (23) until the last mentioned steps are processed with respect to the temperatures of all of said rooms; (25) checking to see if there is a said data "1" stored in step (23); (26) generating a second valve control signal if said data "1" is present in step (25) for opening the one of said valves which is associated with said data "1" checked in step (25); (27) checking to see if there is a said data "0" in step (20); and (28) generating a third valve control signal if said data "0" is present in step (27) for closing the one of said valves which is associated with said data "0".