JPH08200901A - Defrosting controller for refrigerating plant - Google Patents

Abstract

PURPOSE: To enable the implementing of stable defrosting efficiently preventing poor and useless defrosting by always keeping a frosting quantity constant by altering a defrosting cycle automatically against changes in the frosting quantity. CONSTITUTION: In a defrosting control, an internal storage temperature RTC and an internal storage humidity RHB and the frequency and time of raising the internal storage temperature are calculated as to the detection of a frosting quantity and a time difference DEF is calculated between the set defrosting time DEFA and the defrosting time DEFB to alter a defrosting cycle automatically.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a defrosting control device for a refrigerating machine having an off cycle, an electric heater and a defrosting device such as hot gas defrosting.

[0002]

2. Description of the Related Art Defrosting control of a conventional refrigerating apparatus is a defrosting control in which only a defrosting cycle and a defrosting time are set regardless of the amount of frost formed on a cooler, or Japanese Patent Application No. 54-146571. The defrost control as described in the manual is performed, and it is not the defrost control method that optimizes the defrost cycle and the defrost time.

[0003]

In the prior art, the defrosting control of the refrigeration system having the defrosting system generally has a variable function of the defrosting cycle (cooling operation time), but it is set. It is a fixed time, and defrost is carried out regularly. The amount of frost on the cooler varies greatly depending on the type of storage material and the use of the refrigerator, such as the entry of outside air by opening and closing the door. In the fixed defrosting cycle, defrosting is regularly performed regardless of whether the frosting amount is excessive or insufficient, so that in the case of an excessive frosting amount, poor defrosting and cooling failure occur. On the other hand, if the amount of frost is too small, power consumption due to useless defrosting and useless room temperature fluctuations occur.

Further, as means for detecting the amount of frost formation and starting defrosting in order to prevent wasteful defrosting, a method of detecting suction pressure, cooler temperature, air temperature difference between inlet and outlet of the cooler, storage chamber There is a method to start defrosting by detecting the temperature difference between the inside and the cooler, the current value of the blower for the cooler, etc.
Since the temperature is detected, there is a large change depending on the conditions, and there is a problem that it is not stable.

An object of the present invention is to make the amount of frost on the cooler constant and to control the defrosting efficiently and stably.

[0006]

In order to achieve the above object, the present invention relates to the number of times the internal cold storage temperature rises above a preset temperature (Claim 1) and the cumulative time during which it rises above the preset temperature (Claim 1). Item 2), the difference between the preset defrosting time and the actual defrosting time (claim 3), the number of times the internal humidity rises above the preset humidity (claim 4), above the set humidity The defrosting cycle is automatically changed according to the rising integrated time (claim 5).

[0007]

In a refrigerating device having a defrosting device, the number of times and time per unit time when the temperature and humidity in the refrigerator rise above a preset temperature and humidity are detected, and the preset defrosting time and cooling are performed. Detects the time difference from the actual defrosting time when defrosting ends due to equipment temperature, suction pressure, etc., and compares the amount of frosting on the cooler that changes due to the type of stored material and the ingress of outside air by opening and closing the door Is a control that automatically changes the defrost cycle every time in order to prevent excessive and insufficient defrosting and always perform efficient defrosting with a constant frosting amount.

[0008]

Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 shows how the temperature in the refrigerator changes with time according to the present invention. Control of operation and stop of the cooling operation of the refrigerating apparatus is performed by the internal cold ON set temperature RT _B and the internal cold OFF set temperature RT _A.

[0010]-compartment temperature, integrates the frequency and time A, B time increasing the frost amount detection-compartment set temperature RT _C set to relatively high value from the internal on-set temperature RT _B, was first set Control to automatically change the defrost cycle every time.

[0011] The time difference ΔD between the defrosting time DEF _B time to end the defrosting in defrosting set time DEF _A and DEFT _A temperature
The EF time is calculated, and the control for automatically changing the defrost cycle is performed as described above.

FIG. 2 shows how the humidity in the refrigerator changes with time according to the present invention. Pre number humidity assumed with the set to a higher-chamber set humidity RH _A was frost quantity detection-compartment set humidity RH _B of the refrigerator rises and the time C, integrates the D time, defrosting was first set Control to automatically change the cycle every time.

According to the present embodiment, the number and time of temperature and humidity rises in the refrigerator and the defrosting time are calculated, the amount of frost on the cooler is grasped, and the initially set defrosting cycle is calculated. It is possible to perform stable and efficient defrosting by automatically changing the defrosting cycle to a constant defrosting cycle.

[0014]

According to the present invention, the amount of frost on the cooler of the refrigerating apparatus, which varies depending on how the refrigerator is used, such as the type of stored items and the frequency of opening and closing the door of the refrigerator, increases the temperature and humidity inside the refrigerator, and defrosts. By grasping the time, the defrost cycle is automatically changed each time in order to keep the amount of frost constant at all times, resulting in poor defrost due to excessive frost formation, poor cooling, and waste defrost due to insufficient frost formation. The generation of cooling failure can be prevented, and energy-saving and stable and efficient defrosting operation can be performed.

[Brief description of drawings]

FIG. 1 is a state change diagram with respect to elapsed time of a temperature inside a refrigerator according to the present invention.

FIG. 2 is a state change diagram with respect to elapsed time of humidity in the refrigerator.

[Explanation of symbols]

RT _A ... In-compartment OFF set temperature, RT _B ... In-compartment ON set temperature, RT _C ... Frosting amount detection in-compartment set temperature, DEFT _A ... Defrost end detection temperature, RH _A ... In-compartment set humidity, RH _B ... Frost amount detection humidity setting inside the chamber, DEF _A time ... Defrost setting time, DE
F _B time ... Defrost time ending at DEFT _A temperature, ΔDE
F time ... DEF _A- DEF _B , A, B, C, D time ... Time when the frost formation detection temperature and humidity are exceeded.

Claims (1)

[Claims] 1. In a refrigerating apparatus having defrosting control, the temperature in the refrigerator rises above a preset temperature higher than a preset temperature of a refrigerator temperature controller for instructing operation and stop of the refrigerating apparatus per unit time. A defrosting control device for a refrigeration system, which automatically changes a defrosting cycle according to a change in the number of times.