Refrigerator and freezer monitoring device

A temperature-sensitive switch in a refrigerator or freezer, separate from the refrigeration and freezer equipment, remains open when the temperature is below a predetermined level and closes when the temperature rises above the predetermined level. A visible alarm and an audible alarm are provided outside the refrigerator and freezer at a commercial power source wall-type outlet. A battery is electrically connected to the visible and audible alarms via the temperature-sensitive switch whereby when the temperature in the refrigerator or freezer rises above the predetermined level, the alarms are actuated.

The present invention relates to a refrigerator and freezer monitoring 
device. More particularly, the invention relates to a refrigerator and 
freezer monitoring device for indicating when electrical energy is 
supplied thereto and for warning when the temperature rises above a 
predetermined level. 
Objects of the invention are to provide a refrigerator and freezer 
monitoring device of simple structure, which is inexpensive in 
manufacture, installed with facility and convenience in new and existing 
refrigerators and freezers, and functions efficiently, effectively and 
reliably to warn when the temperature rises above a predetermined level. 
BRIEF SUMMARY OF THE INVENTION 
In accordance with the invention, a refrigerator and freezer monitoring 
device indicates when electrical energy is supplied thereto and for 
warning when the temperature rises above a predetermined level. The 
refrigerator and freezer are powered by a commercial power source via a 
wall-type outlet. The refrigerator and freezer monitoring device comprises 
a temperature-sensitive switch in a refrigerator and freezer, separate 
from the refrigeration and freezer equipment. The switch remains open when 
the temperature is below a predetermined level and closes when the 
temperature rises above said predetermined level. A visible alarm is 
provided outside and separate from the refrigerator and freezer at the 
wall-type outlet. An audible alarm is provided outside and separate from 
the refrigerator and freezer at the wall-type outlet. A battery is 
electrically connected to the visible alarm and the audible alarm via the 
temperature-sensitive switch whereby when the temperature in the 
refrigerator and freezer rises above the predetermined level the visible 
and audible alarm means are actuated. A power switch remains closed when 
the commercial power source provides the required power and opens when the 
commercial power source fails. A power indicating lamp at the wall-type 
outlet is electrically connected to the commercial power source via the 
power switch whereby the power lamp is energized as long as sufficient 
power is provided by the commercial power source.

DETAILED DESCRIPTION OF THE INVENTION 
The refrigerator and freezer monitoring device of the invention indicates 
when electrical energy is supplied thereto and warns when the temperature 
in the refrigerator or freezer rises above a predetermined level. This 
results in a saving of the food in the refrigerator or freezer and a 
saving of electrical energy, which would otherwise be expended 
fruitlessly, if the mechanism of the refrigerator or freezer were 
malfunctioning. 
The refrigerator and freezer monitoring device of the invention comprises a 
temperature-sensitive switch 1 (FIGS. 2 and 3) in a refrigerator 2 or 
freezer 3 (FIG. 1) separate from the refrigeration and freezer equipment 
of said refrigerator and freezer. The temperature-sensitive switch 1 may 
comprise any suitable temperature-sensitive switch such as a thermocouple. 
The temperature-sensitive switch 1 remains open when the temperature in 
the refrigerator or freezer is below a predetermined level and closes when 
the temperature rises above said predetermined level. The predetermined 
temperature level for the refrigerator is preferably between 35.degree. F. 
and 45.degree. F. and the predetermined temperature level for the freezer 
is between 0.degree. F. and 10.degree. F. 
A visible alarm such as, for example, a red lamp 4 (FIGS. 1 to 3), is 
provided outside, and separate from, the refrigerator and freezer 2 and 3 
at the wall-type outlet 7 of the commercial power source which powers said 
refrigerator and said freezer. 
An audible alarm 5 of any suitable type such as, for example, a buzzer 
(FIGS. 1 to 3), is provided outside, and separate from, the refrigerator 
and freezer 2 and 3 at the wall-type outlet 7. 
A battery 6 (FIGS. 2 and 3) is electrically connected to the visible alarm 
4 and the audible alarm 5 via the temperature-sensitive switch 1, as shown 
in FIGS. 2 and 3. Thus, when the temperature in the refrigerator or 
freezer rises above the predetermined level, the visible and audible 
alarms are actuated. 
As shown in FIGS. 1 and 3, the refrigerator and freezer 2 and 3 are powered 
by a commercial power source supplied via a power line, the wall-type 
outlet 7 and an electrical connector plug 7. As shown in FIG. 3, a relay 8 
has an energizing winding connected across the commercial power source. 
The relay energizing winding of the relay 8 controls relay contacts 8a and 
8b. The relay contacts 8a are normally closed and the relay contacts 8b 
are normally open. 
The relay contacts 8a function as a power switch and remain closed as long 
as the commercial power source provides the required power, and open when 
the commercial power source fails. A power indicating green lamp 9 (FIGS. 
1 and 3), which is preferably green, is electrically connected to the 
commercial power source at the wall-type outlet 7 via the power switch 8a, 
thus the green power lamp 9 is energized as long as power is provided by 
the commercial power source. 
As shown in FIG. 3, the temperature-sensitive switch 1 remains open as long 
as the temperature in the refrigerator or freezer is at or below the 
predetermined level, thereby maintaining the alarm circuit open, so that 
the alarms 4 and 5 are deactivated. The relay contacts 8b are maintained 
open by the relay energizing winding as long as said winding is energized. 
Upon failure of the commercial power source, however, the relay contacts 
8b close thereby closing the alarm circuit and actuating the alarms 4 and 
5. Since the temperature-sensitive switch 1 is connected in parallel with 
the relay contacts 8b, when the temperature in the refrigerator or freezer 
rises above the predetermined level, the alarm circuit is closed, 
regardless of the condition of the relay contacts 8b, so that the alarms 4 
and 5 are actuated. 
While the invention has been described by means of specific examples and in 
specific embodiments, I do not wish to be limited thereto, for obvious 
modifications will occur to those skilled in the art without departing 
from the spirit and scope of the invention.