PURPOSE: To execute a minute and reliable temperature control by providing control means which turn on and off a cooling unit with respect to opening or closing of a night cover, the presence or absence of turning on an illuminating light, or, rising or falling of temperature of the open air.
CONSTITUTION: A refrigeration showcase is equipped with a nozzle sensor 1, an interior sensor 2 and an air temperature sensor 3 which are three kinds of temperature sensors. When the temperature of the open air is lower than a reference value, or a fluorescent lamp is off, or a night cover is closed, inside temperature of the showcase is compared with a setting temperature. If the inside temperature is not less than the setting temperature TK, a relay is turned on and a solenoid refrigerant feed valve 10 is opened. If the inside temperature is less than the setting temperature TK, the relay is turned off and the valve 10 is closed. On the other hand, when the temperature of the open air exceeds the reference value TA, or the fluorescent lamp is on, or a night cover is open, circulating cold temperature is compared with the setting temperature. If the circulating cold temperature is not less than the setting temperature TC, the relay is turned on and a solenoid refrigerant feed valve 10 is opened. If the circulating cold temperature is less than the setting temperature TC, the relay is turned off and the valve 10 is closed.
OKA YOSHITSUGU
SAKAI KATSUHIRO
| JPS56130573A | 1981-10-13 | |||
| JPS60122874A | 1985-07-01 | |||
| JPS57112669A | 1982-07-13 |