Cooling storage and method of operating the same

• US 8,209,991 B2
• Filed: 03/13/2007
• Issued: 07/03/2012
• Est. Priority Date: 03/13/2007
• Status: Expired due to Fees

• Current Assignee: Hoshizaki Denki Kabushiki Kaisha
• Original Assignee: Hoshizaki Denki Kabushiki Kaisha
• Inventors: Kondou, Naoshi, Hirano, Akihiko, Yatori, Masahide, Kaga, Shinichi, Tashiro, Hideyuki
• Primary Examiner(s): ALI, MOHAMMAD M
• Application Number:
  US12/529,594
• Publication Number:
  US 20100115973A1
• Time in Patent Office: 1,939 Days
• Field of Search: 621/15, 624/41, 624/98, 621/26, 621/29, 700/275
• US Class Current: 62/115
• CPC Class Codes: F25B 2600/2511 Evaporator distribution valves
• CPC Class Codes: F25B 2700/2117 of an evaporator
• CPC Class Codes: F25B 49/022 Compressor control arrangements
• CPC Class Codes: F25B 5/02 arranged in parallel
• CPC Class Codes: F25D 11/022 with two or more evaporators
• CPC Class Codes: F25D 17/067 Evaporator fan units
• CPC Class Codes: F25D 2400/08 Refrigerator tables
• CPC Class Codes: F25D 2700/02 Sensors detecting door opening

Abstract

The liquid refrigerant from the compressor 20 and the condenser 21 is alternately supplied to the cooling device for the freezing room 27F and the evaporator for the refrigeration room 27R through the three-way valve 24, so that the freezing room and the refrigeration room are alternately cooled. Here, the ratio of the refrigerant supply time to each evaporator is controlled based not on a deviation between a target temperature set for each storage room and an actual storage room temperature measured in each storage room, but on an integrated value obtained by integrating the difference of these deviations. In a cooling storage, in which from one compressor a refrigerant is selectively supplied to multiple evaporators respectively disposed in multiple storage rooms of varied thermal loads, a one-storage room cooling mode is prevented from being unnecessarily switched to a alternate cooling mode.

Claims

1. A method of operating a cooling storage, comprising:

a compressor, a condenser, a valve device, a first and a second evaporators, and a throttle device for throttling the refrigerant flowing into each the evaporator,

wherein the refrigerant that has been compressed by the compressor and liquified by the condenser is selectively supplied to the first and the second evaporators by the valve device, so that each of a first and a second storage rooms of varied thermal loads is cooled by the first and the second evaporators,

and said method is characterized by calculating and integrating a deviation between a target temperature set for each the first and the second storage room and an actual storage temperature measured in each storage room at every predetermined time, and changing a ratio of refrigerant supply time for each of the first and the second evaporators by controlling the valve device based on the integrated value.

2. A cooling storage comprising:

a refrigerating cycle comprising the following A1 to A6;

(A1) a compressor for compressing a refrigerant

(A2) a condenser for releasing heat from the refrigerant compressed by the compressor

(A3) a valve device, with its entrance connected with the condenser side while its two exits connected with a first and a second refrigerant supply channels, capable of flow channel switching motion for selectively connecting the entrance side with any one of the first and the second refrigerant supply channels

(A4) a first and a second evaporators provided respectively in the first and the second refrigerant supply channels

(A5) a throttle device for throttling the refrigerant flowing into each evaporator

(A6) a refrigerant circulating channel which connects from the refrigerant exit sides of the first and the second evaporators to the refrigerant sucking side of the compressor a storage body having a first and a second storage rooms of varied thermal loads which are cooled with cold air produced by the first and the second evaporators,

a target temperature setter for setting a target temperature for each of the first and second storage rooms,

a first and a second temperature sensors for detecting a storage room temperature in each storage room,

a device temperature deviation calculator for calculating for each storage room a temperature deviation as a difference between each target temperature of each storage room set in the target temperature setter and a storage room temperature of each storage room detected by each temperature sensor,

an integrator of device temperature deviation between rooms for calculating and integrating a temperature deviation between rooms as a difference for every storage room with respect to the temperature deviation calculated by the device temperature deviation calculator, and

a valve controller for changing an opening ratio of each of the first and the second refrigerant supply channels in the valve device by comparing an integrated value integrated by the integrator of device temperature deviation between rooms with a reference value.

3. A cooling storage according to claim 2, wherein, when increasing an opening ratio of the refrigerant supply channel of one storage room, it is a condition for the valve controller that the storage room temperature of the other room is within a temperature range higher than its set temperature only by a prescribed value.

4. A cooling storage according to claim 3, wherein, when increasing an opening ratio of the refrigerant supply channel of one storage room, it is a condition for the valve controller that the storage room temperature of the other room is within a prescribed temperature range relative to its set temperature continuously for a prescribed time.

5. The cooling storage according to claim 2, wherein the target temperature setter is constituted so as to sequentially output a different target temperature with the lapse of time.

6. The cooling storage according to claim 5, wherein the target temperature setter comprises a memory device for storing a function expressing the temporal changing mode of a target temperature and a target temperature calculator for calculating a target temperature by reading the function stored in the memory device with the lapse of time.

7. The cooling storage according to claim 5, wherein the target temperature setter comprises a memory device for storing the temporal changing mode of a target temperature as a reference table in which the temperature and the lapse of time is contrasted, and a table reading device for reading a target temperature in the memory device with the lapse of time.

8. The cooling storage according to claim 3, wherein the target temperature setter is constituted so as to sequentially output a different target temperature with the lapse of time.

9. The cooling storage according to claim 4, wherein the target temperature setter is constituted so as to sequentially output a different target temperature with the lapse of time.

10. A cooling storage, comprising:

a refrigerating cycle comprising the following A1 to A6;

(A1) a compressor driven by an inverter motor for compressing a refrigerant

(A2) a condenser for releasing heat from the refrigerant compressed by the compressor

(A3) a valve device, with its entrance connected with the condenser side while its two exits connected with a first and a second refrigerant supply channels, capable of flow channel switching motion for selectively connecting the entrance side with any one of the first and the second refrigerant supply channels

(A4) a first and a second evaporators provided respectively in the first and the second refrigerant supply channels

(A5) a throttle device for throttling the refrigerant flowing into each evaporator

(A6) a refrigerant circulating channel which connects from the refrigerant exit sides of the first and the second evaporators to the refrigerant sucking side of the compressor a storage body having a first and a second storage rooms of varied thermal loads which are cooled with cold air produced by the first and the second evaporators,

a target temperature setter for setting a target temperature for each of the first and second storage rooms,

a first and a second temperature sensors for detecting a storage room temperature in each storage room,

a device temperature deviation calculator for calculating for each storage room a temperature deviation as a difference between each target temperature of each storage room set in the target temperature setter and a storage room temperature of each storage room detected by each temperature sensor,

an integrator of device temperature deviation between rooms for calculating and integrating a temperature deviation between rooms as a difference for every storage room with respect to the temperature deviation calculated by the device temperature deviation calculator,

a valve controller for changing an opening ratio of each of the first and the second refrigerant supply channels in the valve device by comparing an integrated value integrated by the integrator of device temperature deviation between rooms with a reference value,

a temperature deviation accumulated value calculator for calculating a temperature deviation accumulated value as an accumulated value of the sum of every storage room with respect to a temperature deviation calculated by the device temperature deviation calculator, and

a rotational speed controller for changing the rotational speed of the inverter motor by comparing an accumulated value calculated by the temperature deviation accumulated value calculator with a reference value.

11. A cooling storage according to claim 10, wherein, when increasing an opening ratio of the refrigerant supply channel of one storage room, it is a condition for the valve controller that the storage room temperature of the other room is within a temperature range higher than its set temperature only by a prescribed value.

12. A cooling storage according to claim 11, wherein, when increasing the opening ratio of the refrigerant supply channel of one storage room, it is a condition for the valve controller that the storage room temperature of the other room is within a prescribed temperature range relative to its set temperature continuously for a prescribed time.

13. The cooling storage according to claim 10, wherein the target temperature setter is constituted so as to sequentially output a different target temperature with the lapse of time.

14. The cooling storage according to claim 11, wherein the target temperature setter is constituted so as to sequentially output a different target temperature with the lapse of time.

15. The cooling storage according to claim 12, wherein the target temperature setter is constituted so as to sequentially output a different target temperature with the lapse of time.