US2305319A - Conditioned storage chamber - Google Patents

Description

1942. G. B. PIRNIE v CONDITIONED STORAGE CHAMBER Filed Oct. 24, 1938 IINVENTOR. 650961.: B. P/PN/i BY ATTQRNEY Patented Dec. 15, 1942 I UNITED STATES PATENT OFFICE CONDITIONEDSTORAGE CHAMBER George B. Pirnie, Center Point, Iowa Application October 24, 1938, Serial No. 236,710

2 Claims.

Thisinvention relates to produce storage and display cases and has particular relation to means for controlling the temperature and moisture content ofproduce stored in such cases.

One of the main objects of my invention is to provide a display case for fresh produce in which the temperature and the humidity may bereadily controlled and in which the produce is readily accessible and in plain View of the customer at all times.

It is another object of my invention to provide a device of this character in which produce of various kinds may be segregated in separate compartments to permit the humidity in each compartment to be maintained at a point best suited for the particular produce.

Still another object of my invention is the provision of a simple and eifective but relatively inexpensive means for cooling the inside of a display case with air from the out-of-doors during cold weather.

Other and further features and objects of the invention will be more apparent to those skilled in the art upon a consideration of the accompanying drawing and following specifications, wherein is disclosed an exemplary embodiment of the invention, with the understanding, however, that such changes may be made therein as fall within the scope of the appended claims, without departing from the spirit of the invention.

In said drawing the figure is a view in perspective showing a display case adapted to be cooled by outside air. Part of the case has been broken away for better illustration of the device.

A large number of vegetables, including Irish potatoes, cabbage, carrots, turnips, lettuce, celery, apples, lemons, etc., do not require a very close regulation of the temperature, but it is preferable that they be kept relatively cold. However, it is necessary that evaporation from their surfaces be kept down to a minimum. To do this, it is preferable that the produce be kept in a closed space to permit the control of humidity and also to permit the produce to be kept out of direct contact with the chilled air or other medium used in cooling.

I have shown in the figure a preferred embodiment of my invention in which cold outside air may be drawn into an insulated container during the cold months of the year to keep in proper condition the fruits and vegetables displayed in airtight display cases above the cooling chamber.

This device includes a closely fitted box or case indicated generally at 80, said case having insulated side walls and fioor.

A plurality of vegetable or fruit display boxes, indicated generally at 90, are supported upon the upper edges of the cooling case. Each of the display cases is preferably comprised of a sheet metal box approximately 10 inches in depth, 18 inches wide by 24 inches long. The top of each sheet metal box is attached to a wooden framework 92 in which glass doors 93 and 94 are adapted to slide. It is necessary that these sliding doors be a very close fit within the side portions of the frame in order to prevent the escape of moisture from the box and to retain the cold conducted through the sides and bottoms of the boxes from the cooling case below.

These display boxes are adapted to permit a high humidity to be carried by the air surrounding the edibles, while at the same time leaving them exposed to View. A source of moisture is supplied within each box and preferably comprises a can of water with a wick.

The entire structure disclosed in the figure makes it possible to maintain the produce in a state of high humidity while at the same time furnishing an economical means for maintaining a relatively low temperature. I

These display cases in themselves serve to keep both fruits and vegetables in good condition for a much longer period of time than possible out in the open store room, the action of the case being dependent mainly upon the high humidity maintained, and the cooling effect I secure.

As explained before, however, a great many commodities will be kept in better condition if they are kept in a cold as well as moist atmosphere.

It is, of course, possible to supply artificial cooling in the summer time, in order to make my device usable the entire year. Any suitable means may be employed to remove heat from the interior of the case.

The wooden frames 92 of the individual display cases are constructed so as to extend several inches beyond the sides of the sheet metal boxes 9|, the overhanging edges permitting the cases to be supported upon the upper edges of the cooling case.

The boxes are placed so as to permit air to freely circulate around all of the sides and the bottoms of all the boxes. A conduit 8i is attached to an opening in oneend of the cooling case to conduct air into the case from the outof-doors. A small exhaust blower 82, powered by an electric motor 83, is located at the opposite end of the case.

As the exhaust blower 82 is energized, a slight vacuum will be created within the case 80 and cool air will be drawn into the conduit 8| from the outside.

The blower 82 may be controlled by the thermostat 86 located within the case, and may be arranged to shut off the blower when sufficient cool air has been drawn into the case.

A weighted flapper valve 84 is pivotally mounted within the intake conduit 8| and arranged to close by gravity when the blower is not in operation to prevent the entry of cold air when not required.

In order that the cool air within the case may be thoroughly distributed and come in contact with the walls and bottoms of all of the display cases, a small vertically directed propeller type fan 8'! is mounted close to the floor of the case. This fan is preferably operated in parallel with the blower 82. A switch 88 is provided to permit both blowers to be completely disconnected if desired. A door 89 is provided at the end of the case to permit access to the interior and also to permit cooling apparatus to be installed in the cooling cabinets if desired during the Warm weather.

When it is desired that thedisplay case be cooled by artificial means, the entire cooling unit may be inserted through the door 88 of the display cabinet. I

It is apparent that a device constructed in accordance with my invention constitutes a simple and inexpensive means for supplying the proper conditions to preserve fruits and vegetables, especially during cool weather. I have, however, adapted the device for all-year-around use by providing for the use of an auxiliary cooling apparatus.

Although I have shown and described certain specific embodiments of my invention, it is apparent that modifications thereof may be made by those skilled in the art. Such modifications may be made without departing from. the spirit and scope of my invention as set forth in the appended claims.

I claim as my invention:

1. In a display case for produce, a means for conditioning the produce comprising a plurality of relatively airtight boxes, each having a glass top, metal sides and bottom, an insulating cabinet having an open top, said boxes supported upon and sealed against the open top thereof, a conduit means connected with the cabinet and forming an intake for cool outside air, an exhaust means comprising a blower also connected with the cabinet and adapted to draw cool air into the cabinet through the intake conduit, through the cabinet and exhaust it to the out-ofdoors, and a means within the cabinet to cause air within the cabinet to wipe all the side and bottom surfaces of the boxes.

2. In a produce display case, a means for utilizing cold outside air during cool weather comprising an intake conduit adapted to carry outside air into the case, an exhaust fan adapted to exhaust air from the case to the outside,'a weighted flapper valve on the intake conduit adapted to close when the exhaust fan is not in operation, means within the display case to cause a thorough distribution of the air within the case, and a thermostatic means within the case to control the exhaust fan in accordance with the temperature of the air within the case.

GEORGE B. PIRNIE.

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