JPS6291772A - How to control a constant temperature oven refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a method for controlling a refrigerator in a thermostatic oven. The present invention relates to a method for controlling a refrigerator that is small and suitable for maintaining a constant temperature gradient with the lowest electric power.

[Background of the invention]

In a constant temperature chamber, when there is a heat generating load in the constant temperature chamber and the temperature is to be raised with a certain temperature gradient, conventionally the refrigerator is turned off.
Control is performed by changing the capacity of the thermal heater according to the temperature rise gradient.

Next, a conventional refrigerator control method will be explained in detail with reference to FIGS. 2 to 4. FIG. 2 shows a sectional view of the constant temperature chamber, where 1 is a constant temperature chamber surrounded by a heat insulating material 2, and 8 is a heat insulating door. Inside the constant temperature room 1, there are installed a refrigerator cooler (heat exchanger) 4, a heater 5, a cross flow fan 6 for circulating indoor air, a dry bulb sensor 7, and a shelf 8 on which a heat generating load 9 is placed. A compressor 10 of a refrigerator, a condenser 11, and a blower 12 for the condenser are installed outside the constant temperature room 1.

In the thermostatic chamber described above, when the temperature inside the thermostatic chamber 1 is raised from TloC to 72° C. over time t by the heater 51C with the heat generating load 9 placed in the thermostatic chamber 1, as shown in FIG. The actual set temperature during the rising process (set by controlling the refrigerator with a microcomputer) is determined by the fourth temperature.
As shown in the figure, the time is set in a stepwise manner.At this time, in the conventional refrigerator control method, the temperature inside the thermostatic chamber is lowered to a temperature t''C (for example, 1°C) lower than the stepwise setting value. When reached, the microcomputer-based VC automatically turns on the refrigerator.
However, in this control method, when the set temperature gradient is gentle A, such as ΔT≦t3, there is no heat generation load in the constant temperature room. Even if the temperature of the refrigerator is rising, the VcON
There is a problem that the heat loss becomes large because it is heated while being cooled.

[Purpose of the invention]

The object of the present invention is to provide a constant temperature chamber refrigerator that can raise the temperature with minimum heat loss and power consumption when increasing the temperature while maintaining a constant temperature gradient regardless of the presence or absence of a heat generating load in the constant temperature chamber. The objective is to provide a control method.

[Summary of the invention]

The present invention installs a heater, a refrigerator cooler, a fan, and a dry bulb sensor in a heating unit surrounded by heat insulating material, and installs a refrigerator compressor and a condenser outside, and heats the In a constant temperature chamber that maintains a constant temperature and humidity in a constant temperature chamber by heating by a heater and cooling by a cooler, the heater is controlled by PID control according to a signal from the dry bulb sensor, and when the temperature inside the constant chamber increases, a set temperature gradient t is set. When the temperature inside the thermostatic chamber rises by a certain level or more above the corresponding step-like set temperature, the refrigerator is automatically turned on by 1/(ON) to reduce heat loss.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In FIG. 2, since the configuration of the recommended tank has been described above, its explanation will be omitted.

In the method for controlling a refrigerator according to the present invention, when the temperature of the thermostatic chamber 1 falls, the refrigerator is automatically turned ON by Vcfi microcomputer control, and the heater 5 is controlled by PID control (in this case, it is turned OFF) by the signal from the dry bulb sensor 7. ) to control the temperature. In addition, during constant operation, the refrigerator is automatically turned on by microcomputer control, and the cooler 4 Vc is turned on.
At the same time, a signal from the dry-bulb sensor 7 indicates that the temperature inside the constant temperature room 1 will rise to t4'C (0.5°C) or more above the stepped set temperature. When the temperature rises, the refrigerator is automatically turned on by the microcomputer-controlled IC. Therefore, no matter how gentle the slope of the set temperature is, if there is no heat generation load in the constant temperature room 1, the refrigerator will not turn on, that is, cooling and heating will not occur at the same time, so heat loss will be small. In addition, when the slope of the set temperature exceeds t,"C with the heat generating load 9 placed in the constant temperature room 1, the refrigerator automatically switches to VCON under microcomputer control.
L, a constant temperature gradient is maintained.

In addition, in this example, the above t+''Cfc0.5°C
However, in order to maintain the temperature gradient with high accuracy, it is possible to reduce the overshoot to 0.1°C. Furthermore, the temperature at t4 is set to a maximum value of 2° C. from a generally allowable range for overshoot.

〔Effect of the invention〕

As explained above, according to the present invention, when there is no heat generation load in the thermostatic chamber, the VC automatically turns off the refrigerator under microcomputer control to raise the temperature, thereby reducing heat loss. By doing so, power consumption can be reduced.

In addition, if there is a heat generation load in the constant temperature room, the refrigerator is automatically turned on by microcomputer control to maintain a constant temperature rise gradient, so the temperature may rise at a slope higher than the set temperature gradient. do not have.

[Brief explanation of drawings]

Figure 1 is a diagram showing how the refrigerator is controlled when the temperature rises in the refrigerator control method V of the present invention, Figure 2 is a cross-sectional view of a constant temperature bath, and Figure 3 is the diagram when the temperature increases in the conventional refrigerator control method R. Refrigerator control diagram, FIG. 4 is an enlarged view of section A in FIG. 8. 1... Constant chamber 4... Refrigerator cooler 5... Heater 7... Rolling ball sensor 9... Heat generation load.

Claims (1)

[Claims] A heater, refrigerator cooler, fan, and dry-bulb sensor are installed in a temperature-controlled room surrounded by insulation, and the refrigerator compressor and condenser are installed outside, allowing heating and cooling by the heater. In a constant temperature chamber that maintains a constant temperature and humidity inside the constant temperature chamber by cooling with a device, the heater is PID-controlled by a signal from the dry bulb sensor, and when the temperature inside the constant temperature chamber rises, step-like settings are set corresponding to a set temperature gradient. When the temperature inside the thermostatic chamber rises by more than a certain temperature,
A method for controlling a refrigerator in a constant temperature bath, characterized in that the refrigerator is automatically turned on.