A low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, a cabinet temperature sensor for detecting an inside temperature of the cabinet, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet, wherein the compressor in the freezing cycle system is activated in response to rise of the inside temperature of the cabinet and deactivated in response to a fall in the inside temperature of the cabinet, and wherein the rate of operation of the electric fan is decreased in accordance with a decrease of temperature or pressure of refrigerant in the freezing cycle system during deactivation of the compressor to thereby reduce consumption of the electric power.
|
7. A low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, a cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, compressor control means responsive to the electric signal from said temperature sensor for activating the compressor in the freezing cycle system in response to rise of the inside temperature of the cabinet and for deactivating the compressor in response to a fall in the inside temperature of the cabinet, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet,
wherein the low temperature storage cabinet comprises:
ambient temperature detection means provided on the cabinet to detect a temperature of outside air; and
fan control means for controlling operation of said electric fan in the cabinet in accordance with a temperature of outside air detected by said ambient temperature detection means during deactivation of said compressor and for decreasing the rate of operation of said electric fan in accordance with a decrease of the temperature of outside air.
6. A low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, a cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, compressor control means responsive to the electric signal from said temperature sensor for activating the compressor in the freezing cycle system in response to rise of the inside temperature of the cabinet and for deactivating the compressor in response to a fall in the inside temperature of the cabinet, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet,
wherein the low temperature storage cabinet comprises:
refrigerant pressure detection means provided in the freezing cycle system to detect pressure of refrigerant in the freezing cycle system; and
fan control means for controlling operation of said electric fan in the cabinet in accordance with refrigerant pressure detected by said pressure detection means during deactivation of said compressor and for decreasing the rate of operation of said electric fan in accordance with a decrease of the refrigerant pressure.
1. A low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, a cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, compressor control means responsive to the electric signal from said temperature sensor for activating the compressor in the freezing cycle system in response to rise of the inside temperature of the cabinet and for deactivating the compressor in response to a fall in the inside temperature of the cabinet, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet,
wherein the low temperature storage cabinet comprises:
refrigerant temperature detection means provided in the freezing cycle system to detect a temperature of refrigerant in the freezing cycle system; and
fan control means for controlling operation of said electric fan in the cabinet in accordance with a temperature of refrigerant detected by said detection means during deactivation of said compressor and for decreasing the rate of operation of said electric fan in accordance with a decrease of the refrigerant temperature.
0. 11. A low temperature storage cabinet having a freezing cycle system comprising:
a compressor, a condenser, a throttle and an evaporator, a cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, temperature setting means for setting an inside temperature of the cabinet to a predetermined temperature, compressor control means responsive to the electric signal from said cabinet temperature sensor for activating said compressor in the freezing cycle system when the inside temperature of the cabinet rises more than the predetermined temperature and for deactivating said compressor when the inside temperature of the cabinet falls to less than the predetermined temperature, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet,
wherein the low temperature storage cabinet comprises:
fan control means for operating said electric fan in the cabinet at a predetermined rate of operation during deactivation of said compressor in a condition where the inside temperature of the cabinet is set less than the predetermined temperature by adjustment of said temperature setting means and for operating said electric fan at a rate of operation less than the predetermined rate of operation during deactivation of said compressor in a condition where the inside temperature of the cabinet is set more than or equal to the predetermined temperature value by adjustment of said temperature setting means.
10. A low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, temperature setting means for setting an inside temperature of the cabinet, compressor control means responsive to the electric signal from said cabinet temperature sensor for activating said compressor when the inside temperature of the cabinet rises in a nominal value more than an inside temperature set by said temperature setting means and for deactivating said compressor when the inside temperature of the cabinet falls in the nominal value less than the inside temperature set by said temperature setting means, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet,
wherein the low temperature storage cabinet comprises:
ambient temperature detection means for detecting a temperature of outside air;
first fan control means for operating said electric fan in the cabinet at a predetermined rate of operation during deactivation of said compressor when the inside temperature set by said temperature setting means is less than a predetermined temperature; and
second fan control means for decreasing the rate of operation of said electric fan in accordance with a decrease of the temperature of outside air detected by said ambient temperature detection means during deactivation of said compressor when the inside temperature set by said temperature setting means is more than the predetermined temperature.
9. A low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, temperature setting means for setting an inside temperature of the cabinet, compressor control means responsive to the electric signal from said cabinet temperature sensor for activating said compressor when the inside temperature of the cabinet rises in a nominal value more than an inside temperature set by said temperature setting means and for deactivating said compressor when the inside temperature of the cabinet falls in the nominal value less than the inside temperature set by said temperature setting means, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet,
wherein the low temperature storage cabinet comprises:
refrigerant pressure detection means provided in the freezing cycle system for detecting pressure of refrigerant in the freezing cycle system;
first fan control means for operating said electric fan in the cabinet at a predetermined rate of operation during deactivation when the inside temperature set by said temperature setting means is less than a predetermined temperature; and
second fan control means for decreasing the rate of operation of said electric fan in accordance with a decrease of the refrigerant pressure detected by said refrigerant pressure detection means during deactivation of said compressor when the inside temperature set by said temperature setting means is more than the predetermined temperature.
8. A low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, a cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, temperature setting means for setting an inside temperature of the cabinet, compressor control means responsive to the electric signal from said cabinet temperature sensor for activating said compressor when the inside temperature of the cabinet rises in a nominal value more than an inside temperature set by said temperature setting means and for deactivating said compressor when the inside temperature of the cabinet falls in the nominal value less than the inside temperature set by said temperature setting means, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet,
wherein the low temperature storage cabinet comprises:
refrigerant temperature detection means provided in the freezing cycle system for detecting a temperature of refrigerant in the freezing cycle system;
first fan control means for operating said electric fan in the cabinet at a predetermined rate of operation during deactivation of said compressor when the inside temperature set by said temperature setting means is less than a predetermined temperature; and
second fan control means for decrease the rate of operation of said electric fan in accordance with a decrease of the refrigerant temperature detected by said refrigerant temperature detection means during deactivation of said compressor when the inside temperature set by said temperature setting means is more than the predetermined temperature.
2. A low temperature storage cabinet as claimed in
3. A low temperature storage cabinet as claimed in
4. A low temperature storage cabinet as claimed in
5. A low temperature storage cabinet as claimed in
|
1. Field of the Invention
The present invention relates to a low temperature storage cabinet such as a refrigerator, a freezer or the like in which operation of a refrigerant compressor in a freezing cycle system is controlled to maintain the interior of the cabinet at a predetermined low temperature, and more particularly to a low temperature storage cabinet in which the rate of operation of an electric fan in the cabinet is controlled during deactivation of the compressor.
2. Description of the Prior Art
Disclosed in Japanese Utility Model Publication No. 62-29909 is a low temperature storage cabinet of this kind in which the electric fan in the cabinet is operated only for a period of time set by a start switch during deactivation of the compressor for decreasing a difference in temperature between upper and lower compartments in the cabinet and is stopped only for a period of time set by a stop switch for saving the electric power.
In the conventional low temperature storage cabinet, a difference in temperature between the upper and lower compartments in the cabinet is estimated by a user for setting each period of time for control of the electric fan in the cabinet. If there is an error in estimation of the difference in temperature between the upper and lower compartments or the period of time is erroneously determined by the user, the difference in temperature between the upper and lower compartments becomes large, and consumption of the electric power may not be properly reduced in accordance with the inside temperature of the cabinet.
It is, therefore, a primary object of the present invention to provide a low temperature storage cabinet when operation of electric fan in the cabinet is controlled in accordance with a difference in pressure between upper and lower compartments of the cabinet to reduce consumption of the electric power without causing any problem discussed above.
According to the present invention, the object is accomplished by providing a low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, a cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, compressor control means responsive to the electric signal from the temperature sensor for activating the compressor in the freezing cycle system in response to rise of the inside temperature of the cabinet and for deactivating the compressor in response to a fall in the inside temperature of the cabinet, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet, wherein the low temperature storage cabinet comprises refrigerant temperature detection means provided in the freezing cycle system to detect a temperature of refrigerant in the freezing cycle system, and fan control means for controlling operation of the electric fan in the cabinet in accordance with a temperature of refrigerant detected by the detection means during deactivation of the compressor and for decreasing the rate of operation of the electric fan in accordance with a decrease of the refrigerant temperature.
According to an aspect of the present invention, there is provided a low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, a cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, compressor control means responsive to the electric signal from the temperature sensor for activating the compressor in the freezing cycle system in response to rise of the inside temperature of the cabinet and for deactivating the compressor in response to a fall in the inside temperature of the cabinet, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet, wherein the low temperature storage cabinet comprises refrigerant pressure detection means provided in the freezing cycle system for detecting pressure of refrigerant in the freezing cycle system, and fan control means for controlling operation of the electric fan in the cabinet in accordance with refrigerant pressure detected by the pressure detection means during deactivation of the compressor and for decreasing the rate of operation of the electric fan in accordance with a decrease of the refrigerant pressure.
According to another aspect of the present invention, there is provided a low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, a cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, compressor control means responsive to the electric signal from said temperature sensor for activating the compressor in the freezing cycle system in response to rise of the inside temperature of the cabinet and for deactivating the compressor in response to a fall in the inside temperature of the cabinet, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet, wherein the low temperature storage cabinet comprises ambient temperature detection means provided on the cabinet to detect a temperature of outside air, and fan control means for controlling operation of the electric fan in the cabinet in accordance with a temperature of outside air detected by the ambient temperature detection means during deactivation of the compressor and for decreasing the rate of operation of the electric fan in accordance with a decrease of the temperature of outside air.
In each practical embodiment of the low temperature storage cabinets described above, it is preferable that the fan control means comprises means for intermittently operating the electric fan in the cabinet during deactivation of the compressor and for changing the operation time and the stopping time of the electric fan to control the rate of operation of the electric fan. It is also preferable that the fan control means comprises means for selectively effecting continual operation of the electric fan or intermittent operation of the electric fan during deactivation of the compressor to control the rate of operation of the electric fan.
According to a further aspect of the present invention, there is provided a low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, a cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, temperature setting means for setting an inside temperature of the cabinet, compressor control means responsive to the electric signal from the cabinet temperature sensor for activating the compressor when the inside temperature of the cabinet rises in a nominal value more than inside temperature set by the temperature setting means and for deactivating the compressor when the inside temperature of the cabinet falls in the nominal value less than the inside temperature set by the temperature setting means, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet, wherein the low temperature storage cabinet comprises refrigerant temperature detection means for detecting a temperature of refrigerant in the freezing cycle system, first fan control means for operating the electric fan in the cabinet at a predetermined rate of operation during deactivation of the compressor when the inside temperature set by the temperature setting means is less than a predetermined temperature, and second fan control means for decreasing the rate of operation of the electric fan in accordance with a decrease of the refrigerant temperature detected by the refrigerant temperature detection means during deactivation of the compressor when the inside temperature set by the temperature setting means is more than the predetermined temperature.
According to an aspect of the present invention, there is provided a low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, a cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, temperature setting means for setting an inside temperature of the cabinet, compressor control means responsive to the electric signal from the cabinet temperature sensor for activating the compressor when the inside temperature of the cabinet rises in a nominal value more than an inside temperature set by the temperature setting means and for deactivating the compressor when the inside temperature of the cabinet falls in the nominal value less than the inside temperature set by the temperature setting means, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet, wherein the low temperature storage cabinet comprises refrigerant pressure detection means for detecting pressure of refrigerant in the freezing cycle system, first fan control means for operating the electric fan in the cabinet at a predetermined rate of operation during deactivation of the compressor when the inside temperature set by the temperature setting means is less than a predetermined temperature, and second fan control means for decreasing the rate of operation of the electric fan in accordance with a decrease of the refrigerant pressure detected by the refrigerant pressure detection means during deactivation of the compressor when the inside temperature set by the temperature setting means is more than the predetermined value.
According to another aspect of the present invention, there is provided a low temperature storage cabinet having a freezing cycle system composed of a compressor, a condenser, a throttle and an evaporator, cabinet temperature sensor for detecting an inside temperature of the cabinet and for producing an electric signal indicative of the detected inside temperature, temperature setting means for setting an inside temperature of the cabinet, compressor control means responsive to the electric signal from the cabinet temperature sensor for activating the compressor when the inside temperature of the cabinet rises in a nominal value more than an inside temperature set by the temperature setting means and for deactivating said compressor when the inside temperature of the cabinet falls in the nominal value less than the inside temperature set by the temperature setting means, and an electric fan provided in the cabinet for circulating cooled air in the interior of the cabinet, wherein the low temperature storage cabinet comprises ambient temperature detection means for detecting a temperature of outside air, first fan control means for operating the electric fan in the cabinet at a predetermined rate of operation during deactivation of the compressor when the inside temperature set by the temperature setting means is less than a predetermined value, and second fan control means for decreasing the rate of operation of the electric fan in accordance with a decrease of the temperature of outside air detected by the ambient temperature detection means during deactivation of the compressor when the inside temperature set by the temperature setting means is more than the predetermined value.
Other objects, features and advantages of the present invention will be more readily appreciated from the following detailed description of preferred embodiments thereof when taken together with the accompanying drawings, in which:
In
An electric control apparatus 20A for control of the compressor 14, the electric fan 18 in cabinet 10 and the cooling fan 19 of condenser 15 is contained in a control box 20 mounted within the refrigerator. As shown in
As shown in
Assuming that a power source switch of the refrigerator has been closed, the microcomputer 21 starts to execute the main program at step 100 of FIG. 4 and repeats execution of processing at step 102 to 112. When the thermo-switch 23 is turned on in response to rise or the inside temperature of cabinet 10 during execution of the main program, the computer 21 determines a “Yes” answer at step 102 and maintains each operation of the compressor 14, the condenser fan 19 and the electric fan 18 in cabinet 10 by processing at step 104 and 106. Thus, the freezing cycle system is maintained in an activated condition to cool the interior of cooling compartment 12a, and the cooled air from cooling compartment 12 is circulated by operation of the electric fan 18 into the storage compartment 12b so that the inside temperature of cabinet 10 is uniformly lowered. When the thermo-switch 23 is turned off due to drop of the inside temperature of cabinet 10, the computer 21 determines a “No” answer at step 102 and stops each operation of the compressor 14 and condenser fan 19 at step 108 to deactivate the freezing cycle system and determines at step 110 whether the saving switch 25 has been turned on or not. If the answer at step 110 is “No”, the computer 21 returns the program to step 102 and maintains the operation of the electric fan 18 in cabinet 10 even when the freezing cycle system is deactivated. When the thermo-switch 23 is turned on due to rise of the inside temperature of cabinet 10 caused by opening and closing of the cabinet door, the computer 21 determines a “Yes” answer at step 102 and activates the freezing cycle system by processing at step 104 and 106. With such control of the freezing cycle system, the inside temperature of cabinet 10 is maintained approximately at the predetermined temperature.
When the saving switch 25 is turned on, the computer 21 determines a “Yes” answer at step 110 and causes the program to proceed to step 112 for execution of a cabinet fan control routine shown in FIG. 5. When started execution of the cabinet fan control routine at step 200, the computer 21 is applied with an electric signal indicative of a temperature T of the refrigerant detected by sensor 24 and executes processing at step 204 to 212 for setting a measurement time of timer 21a in accordance with the refrigerant temperature T. When the refrigerant temperature T is more than a first predetermined value T1 (for instance, 50° C.), the measurement time is defined by a first predetermined time TM1 (for instance, one and half minutes). When the refrigerant temperature T is less than the first predetermined value T1 and more than a second predetermined value T2 (for instance, 30° C.) less than the first predetermined value T1, the measurement time is defined by a second predetermined time TM2 (for instance, two and half minutes). When the refrigerant temperature T is less than the second predetermined value T2, the measurement time is defined by a third predetermined time TM3 (for instance, three minutes). Thus, the measurement time of timer 21a is successively increased in accordance with a decrease of the refrigerant temperature T.
After processing at step 204 to 212, the timer 21a starts to count down the measurement time, while the computer 21 repeats execution of processing at step 214 to 220 unless the saving switch 25 is turned off or the thermo-switch 23 is turned on. Thus, the electric fan 18 in cabinet 10 is deactivated by processing at 218 during execution of processing at step 214 to 220. When the timer 21a finishes countdown of the measurement time, the computer 21 determines a “Yes” answer at step 216 and causes the program to proceed to step 222.
At step 222, the computer 21 defines the measurement time of timer 21a as a fourth predetermined time TM4 (for instance, fifteen seconds) regardless of the refrigerant temperature T. In such an instance, the timer 21a starts to count down the measurement time TM4, while the computer 21 repeats execution of processing at step 224 to 230 unless the saving switch 25 is turned off or the thermo-switch 23 is turned on. Thus, the electric fan 18 in cabinet 10 is operated by processing at step 228 during execution of processing at step 224 to 230. When the timer 21a finishes countdown of the measurement time, the computer 21 determines a “Yes” answer at step 226 and finishes execution of the cabinet fan control routine at step 234.
When the saving switch 25 is turned on in a condition where the thermo-switch 23 has been turned off to deactivate the freezing cycle system, the electric fan 18 in cabinet 10 is operated for the fourth predetermined time TM4 and is intermittently stopped for the predetermined times TM1, TM2, TM3. (see
As is understood from the above description, when the saving switch 25 is turned on, the electric fan 18 in cabinet 10 is intermittently operated and stopped in a condition where the freezing cycle system is deactivated. Although in such an instance, the operation time of electric fan 18 is defined by the predetermined time TM4, the stopping time of electric fan 18 is successively increased to the predetermined times TM1, TM2 and TM3 in accordance with a decrease of the refrigerant temperature T. As a result, the rate of operation of electric fan 18 is decreased in accordance with a fall in the refrigerant temperature T.
The refrigerant temperature T utilized for control of the rate of operation of electric fan 18 in cabinet 10 rises in a condition where the difference in temperature between the upper and lower compartments of cabinet 10 increases due to rise of the temperature of outside air or opening and closing of the cabinet door. Thus, the rate of operation of the compressor 14 in the freezing cycle system is increased in accordance with the rise of the refrigerant temperature T. Accordingly, even when the rate of operation of electric fan 18 is decreased in accordance with a fall in the refrigerant temperature, the inside temperature of cabinet 10 is uniformly maintained at the predetermined value without increasing the difference in temperature between the upper and lower compartments of cabinet 10. This is useful to automatically reduce consumption of the electric power in a reliable manner.
Although in the foregoing embodiment, the stopping time of electric fan 18 is changed at three steps in accordance with the refrigerant temperature T in a condition where the saving switch 25 has been turned on, the stopping time of electric fan 18 may be changed at two steps or more than four steps.
Illustrated in
In addition, the cabinet fan control routine shown in
After processing at step 216, the computer 21 determines at step 222a whether the refrigerant temperature T is more than the predetermined value T2 or not. If the answer at step 222a is “Yes”, the predetermined value TM2 (for instance, twenty minutes) is set as the measurement time of timer 21a by processing at step 222b. If the answer at step 222a is “No”, the predetermined value TM4 (for instance, fifteen minutes) is set as the measurement time of timer 21a by processing at step 222c. Subsequently, the operation time of electric fan 18 is set in accordance with the refrigerant temperature T by processing at step 226 and 228.
With such execution of the cabinet fan control routine shown in
In a practical embodiment of the present invention, an additional electric fan 31 may be further provided within the cabinet 10 as shown by broken lines in
In the practical embodiment described above, a speed control circuit 41 may be disposed between the driving circuit 22 and the electric fan 18 in cabinet 10, as shown by broken lines in FIG. 2. In this embodiment, the speed control circuit 41 is provided in the form of an inverter or phase control circuit for controlling the rotation speed of electric fan 18, and the main program of
In a modification of the foregoing embodiment, the refrigerant temperature sensor 24 may be replaced with a refrigerant pressure sensor 42 disposed between the condenser 15 and dryer 16 for detecting refrigerant pressure in the freezing cycle system, as shown by broken lines in
In another modification of the foregoing embodiment, an outside air temperature sensor 43 may be provided on the cabinet 10 for detecting the temperature of outside air as shown by broken lines in
Illustrated in
Assuming that the power source switch of the refrigerator has been closed, the computer 21 starts to execute the main program shown in
After processing at step 152 and 154, the computer 21 repeats execution of processing at step 156 to 174. If the first flag FLG1 is “1”, the computer 21 determines a “Yes” answer at step 156 and determines at step 158 whether or not an inside temperature C of the cabinet 10 detected by sensor 23a is less than a lower limit temperature Cs−ΔC1 defined by a difference between the set temperature Cs and a nominal temperature ΔC1 (for instance, 2° C.). If the answer at step 158 is “No”, the computer 21 repeats processing at step 156 and 158. If the answer at step 158 is “Yes”, the computer 21 deactivates the compressor 14 and condenser fan 19 at step 160 and sets the first flag FLG1 to “0” indicative of deactivation of the compressor 14 at step 162. Subsequently, the computer 21 determines at step 164 whether the second flag FLG2 is “1” or not. If the second flag FLG2 is set as “0” at the initial setting, the computer 21 determines “No” answer at step 164 and maintains the operation of cabinet fan 18 at step 174.
When the program is returned to step 156 after processing at step 174, the computer 21 determines a “No” answer at step 156 and causes the program to proceed to step 168. At step 168, the computer 21 determines whether or not the inside temperature of the cabinet 10 detected by sensor 23a is more than an upper limit temperature Cs+ΔC2 defined by the sum of the set temperature Cs and a nominal temperature ΔC2 (for instance, 1.5° C.). If the answer at step 168 is “No”, the computer 21 repeats processing at step 164, 174, 156 and 168 during which the freezing cycle system is deactivated.
When the inside temperature C of the cabinet 10 becomes more than the upper limit temperature Cs+ΔC2, the computer 21 determines a “Yes” answer at step 168 and activates the compressor 14 and condenser fan 19 at step 170 to cool the interior of cooling compartment 12a and storage compartment 12b. After processing at step 170, the computer 21 sets the first flag FLG1 to “1” at step 172 and maintains the operation of cabinet fan 18 by processing at step 174. With such processing at step 156 to 164 and 168 to 174, the freezing cycle system is repeatedly activated and deactivated to maintain the inside temperature C of cooling compartment 12a and storage compartment 12b approximately at the set temperature Cs between the lower limit temperature Cs−ΔC1 and the upper limit temperature Cs+ΔC2.
During execution of the main program described above, the computer 21 executes the timer interruption program of
At step 316, the computer 21 causes the display 28 to indicate the set temperature Cs on the display panel. After processing at step 316, the computer 21 causes the display 28 at step 318 to indicate whether the power saving mode is selected or not. When the power saving mode is not selected, the computer 21 causes the display to put out a decimal point in a lower order of the set temperature Cs. When the power saving mode is selected, the computer 21 causes the display to put on the decimal point.
When the set temperature Cs is changed by processing at step 302 to 310, the computer 21 executes processing at step 156 to 164 and 168 to 174 of
When started to execute the cabinet fan control routine of
When the program proceeds to step 246 after processing at step 216, the computer 21 determines whether the set temperature Cs is less than the predetermined value Cso (for instance, 0° C.) or not. If the answer at step 246 is “Yes”, the computer 21 sets a predetermined time TM6 as the measurement time of timer 21a at step 248 and causes the program to proceed to step 224. If the answer at step 246 is “No”, the computer 21 executes processing at step 222 in the same manner as in the foregoing embodiment for setting the fourth predetermined time TM4 as the measurement time of timer 21a. In this instance, the predetermined time TM6 is set as a larger value (for instance, fifteen seconds) than the fourth predetermined time TM4. Accordingly, if the set temperature Cs is less than the predetermined value Cso, the operation time of electric fan 18 defined by processing at step 226 and 228 becomes more than that in a condition where the set temperature Cs is higher than the predetermined value Cso.
As a result, when the set temperature Cs is less than the predetermined value Cso at the power saving mode, the rate of operation of electric fan 18 during deactivation of the compressor 14 is fixed to a relatively high value regardlessly of the refrigerant temperature T. Thus, even when the inside temperature of cabinet 10 is set at a lower value than 0° C. for preserving fresh foods such as fish, meat and the like in a slightly frozen condition, fluctuation of the inside temperature of storage compartment 12b caused by intermittent operation of the electric fan 18 is restrained to prevent the preserved fresh foods from melting or freezing. In addition, when the set temperature Cs is higher than the predetermined value Cso, the rate of operation of electric fan 18 in cabinet 10 is decreased in accordance with a decrease of the refrigerant temperature T in the same manner as in the foregoing embodiment to automatically reduce consumption of the electric power.
Illustrated in
Illustrated in
During execution of the main program of
With such control of the electric fans 18 and 19 as described above, even when the inside temperature of cabinet 10 is set at a lower temperature than 0° C. for preserving fresh foods such as fish, meat and the like in a lightly frozen condition, fluctuation of the inside temperature of storage compartment 12b is retrained to prevent the preserved foods from melting or freezing.
Illustrated in
During execution of the main program of
With such control of the electric fan 18 as described above, even when the inside temperature of cabinet 10 is set at a lower temperature than 0° C. for preserving fresh foods such fish, meat and the like in a slightly frozen condition, fluctuation of the inside temperature of cabinet 10 is restrained to prevent the preserved foods from melting or freezing. In addition, when the set temperature Cs is higher than the predetermined value Cso to preserve fresh foods without causing any spoil thereof, the rate of operation of the electric fan 18 is decreased in accordance with a decrease of the refrigerant temperature T to automatically reduce consumption of the electric power.
Suyama, Tomio, Shima, Tsuyoshi
Patent | Priority | Assignee | Title |
Patent | Priority | Assignee | Title |
3733841, | |||
4467617, | Oct 17 1980 | The Coca-Cola Company | Energy management system for chilled product vending machine |
4481787, | Jul 16 1982 | Whirlpool Corporation | Sequentially controlled single evaporator refrigerator |
4485633, | Oct 18 1982 | The Coca-Cola Company | Temperature-based control for energy management system |
5255530, | Nov 09 1992 | Whirlpool Corporation | System of two zone refrigerator temperature control |
5490394, | Sep 23 1994 | MULTIBRAS S A ELETRODOMESTICOS | Fan control system for the evaporator of refrigerating appliances |
5782101, | Feb 27 1997 | Carrier Corporation | Heat pump operating in the heating mode refrigerant pressure control |
JP6229909, |
Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
Aug 03 2001 | Hoshizaki Denki Kabushiki Kaisha | (assignment on the face of the patent) | / |
Date | Maintenance Fee Events |
Mar 05 2009 | ASPN: Payor Number Assigned. |
Jan 05 2011 | M1553: Payment of Maintenance Fee, 12th Year, Large Entity. |
Date | Maintenance Schedule |
Dec 09 2011 | 4 years fee payment window open |
Jun 09 2012 | 6 months grace period start (w surcharge) |
Dec 09 2012 | patent expiry (for year 4) |
Dec 09 2014 | 2 years to revive unintentionally abandoned end. (for year 4) |
Dec 09 2015 | 8 years fee payment window open |
Jun 09 2016 | 6 months grace period start (w surcharge) |
Dec 09 2016 | patent expiry (for year 8) |
Dec 09 2018 | 2 years to revive unintentionally abandoned end. (for year 8) |
Dec 09 2019 | 12 years fee payment window open |
Jun 09 2020 | 6 months grace period start (w surcharge) |
Dec 09 2020 | patent expiry (for year 12) |
Dec 09 2022 | 2 years to revive unintentionally abandoned end. (for year 12) |