US3191794A - Protective handle for thermally insulated bulk storage container - Google Patents

Description

June 29, 1965 w. E. PERKINS PROTECTIVE HANDLE FOR THERMALLY INSULATED BULK STORAGE CONTAINER Original Filed Feb. 1, 1962 2 Sheets-Sheet 1 INVENTOR. WARREN E. PERKINS A TTORNEV June 29, 1965 w. E. PERKINS 3,191,794

PROTECTIVE HANDLE FOR THERMALLY INSULATED BULK STORAGE CONTAINER Original Filed Feb. 1, 1962 2 Sheets-Sheet 2 INVENTOR. WARREN E. PERKINS WWW A T TORNEY United States Patent 3,191,794 PROTECTIVE HANDLE FGR THERMALLY INSU- LATED BULK STORAGE CQNTAINER Warren E. Perkins, Grand Island, N.Y., assignor to Union Carbide Corporation, a corporation of New York Original application Feb. 1, 1962, Ser. No. 172,052. Divided and this application Oct. 9, 1962, Ser. No.

4 Claims. (Cl. 220-14) This is a division of my pending application Serial No. 172,052, filed February 1, 1962, entitled Thermally Insulated Bulk Storage Container.

This invention relates to an improved container for the storing and conveying of perishable commodities, and more particularly concerns a portable container for the conservation of products which must be held at low temperatures for substantial periods of time.

In the past, several difliculties have been encountered in the conservation and conveyance of low temperature products, for example, perishable commodities such as whole blood, pharmaceuticals, enzymes, semen, living tissues, or other biological specimens, which must be held at low temperatures for sustained periods of time.

One of the important difliculties concerns the provision of a light-weight, portable storage container capable of being easily handled for shipment by modern transportation, including automotive passenger car. Another problem is the provision of a compact transporting container for maintaining the stored product for a considerable length of time at the low temperature necessary to avoid spoilage.

Still another problem involves the provision of a portable container having a relatively large opening to adapt it for use in the conveyance of packaged liquid products, as well as solid products of Various shapes and sizes, which cannot be simply introduced and withdrawn as can a free-flowing fluid.

Yet another problem involves the efiicient utilization of the storage capacity, so that a maximum amount of material may be assembled and stored in an orderly arrangement in the container without damage by squeezing or packing down. 7

Such problems are very difficult to solve in portabletype containers, primarily because the heat leak problem is exceptionally critical in small vessels. The ratio of sulface area to storage volume in small containers is very large compared to the large stationary-type, conven tional storage containers. In addition, the efiicient utilization of space for product storage places a severe limit on the volume available for the refrigerant.

In the present process for storing and shipping perishable commodities in small quantities, such as bull semen for the artificial insemination of cattle, the semen is shipped in ampules refrigerated by direct immersion in water and ice. The difficulty with using solid refrigerant is that it restricts the mobility of any mechanical equipment or parts that might be used inside the container. Furthermore, much of the stored semen may be wasted by spoilage due to the short term virility of semen at such relatively warm temperatures.

If the semen material could be stored in frozen condition, and transported in portable containers at very low temperatures, such as liquid air or liquid nitrogen temperatures, the material would retain its potency indefinitely, and there would be little or no wastage. The prime advantage of such a system is, of course, that close scheduling of individual semen ampule shipments will no longer be required. Another advantage is that a full and complete selection of different breeds and strains may be made available at all times, independently of the time the semina of such breeds and strains werecollected.

In order that such a refrigerated container have the requisite portability, and still operate with maximum efficiency and economy, it is necessary that certain inherent problems in design and construction be overcome.

To illustrate by way of example the difficulties that are inherent in the provision of a portable low temperature container, suppose for example that it is desired to store several hundred ampules of semen specimens by immersing them in a bath of liquid nitrogen. Assuming that the contents must be stored in ;a double-walled container at liquid nitrogen temperature (320 F.) for about four weeks without an excessive volume of re frigerant, and without replenishment of refrigerant, this will require the provision of a highly efficient insulation such as, for example, a high vacuum polished metal surface system, or a suitable insulating material in vacuum system. This will mean that a major path of heat transmission into the container will be through the neck tube of the container and other supporting members. Assume further that the height of the container does not exceed 22 inches, in order that the container may fit in the rear trunk compartment of an automobile.

To more fully appreciate the problem involved in fulfilling the above conditions, it should be pointed out that using a conventional small diameter, thin-walled neck tube-to support the inner container inside the outer shell, the contribution of the neck tube to the overall heat transmission will be of such magnitude that attainment of a four week refrigerant holding time without replenishment of refrigerant will be of all intents and purposes, impossible to achieve. Obviously for large neck tube openings, even greater heat leaks will be experienced, since a significant portion of an otherwise well insulated area is thus replaced by an uninsulated opening. As a consequence, refrigeration losses by all modes of heat transfer will be considerably greater.

It is, therefore, an important object of the present invention to provide an improved portable container having a suificiently low rate of heat transfer to enable perishable products such as semen and the like to be stored in the refrigerated state at lower temperatures and for longer periods of time than has heretofore been possible.

Another object of the present invention is to provide in a low temperature storage container, an improved means for evacuating the container insulation space.

A still further object of the present invention is to provide in a low temperature storage container means for protecting the container from damaging blows or tampering.

Other objects, features and advantages of the present invention will be readily apparent from the following detailed description of certain preferred embodiments thereof, taken in conjunction with the accompanying drawings in which: 7 FIG. 1 is a view in vertical cross-section of an improved container embodying the principles of the present invention, also shown in a means for holding units of lowtemperature products within the container storage area;

FIG. 2 is a plan view of the container shown in FIG. 1 with a portion broken away to show underlying parts;

FIG. 3 is a sectional view of one of the handles of the container taken along line 33 in FIG. 2;

-FIG. 4 is a fragmentary sectional view of one of the handles taken along line 4-4 in FIG. 2.

To attain the above objects, use is made in the present invention of highly efiicient insulation, such as, for example, a high vacuum-polished metal surface system or a suitable insulating material. According to the broad aspects of the invention, a heat insulated vessel is partly filled with a liquefied gas material, such as liquid nitrogen, which act as a refrigerant for the storage of products at low temperatures. The invention will be described in 3,191,794 Patented June 29, 1965 (.3 connection with a portable container having approximately 25 liters storage capacity for storing frozen ampules of bull semen, but it is to be understood that the same principles apply, regardless of the size of the portable container and the nature of the specific material which is stored. The ampules are conveniently grouped and arranged in ampule-holding baskets, which are immersed in the refrigerant of the container. Each basket contains a number of ampule-holding rods, which may be conveniently and individually inserted in, or removed from its associated basket without withdrawing the basket completely from the container, and without disturbing the remaining holding rods in the basket. Each ampule basket is readily accessible from the neck of the container without disturbing or requiring a major re-arrangement of adjoining ampule baskets.

Double-walled container In FIG. 1 is shown a liquefied gas holding container or double-walled liquid cylinder embodying the principles of the present invention. The double-walled container comprises an inner vessel 11 made from an impervious metal such as stainless steel. This metal is found to resist embrittlernent at the low refrigerant temperatures normally encountered when the refrigerant L is such as liquid nitrogen. The inner vessel is generally cylindrically shaped, having at its lower end a dished bottom wall 12, and at its upper end an annular shoulder portion 13, which terminates in an elongated, tubular supporting neck 14. A splash plate 15 may be welded to the inner wall near the top of the vessel 11. The inner vessel 11 is surrounded by a gas-tight shell or jacket 17 of suitable metallic material, which completely encompasses the inner vessel to provide an intervening evacuable insulating space 18 which functions to afford substantial resistance to heat leakage therethrough. 7 The outer shell 17 includes a shoulder portion 19, and a tapering neck portion 20 which supports the inner vessel 11 at the upper end of its neck 14 by an annular sealing weld joint 21, said joint constituting the lip of the container 10.

For ease of portability and transportatiom'it is desirable to restrict the weight of the container, and to dimension the container so that it can be carried in the trunk of a car. I have found that in a liter container, an inner and outer vessel diameter of 14 inches and 18 inches, respectively, and an overall container height of 22 inches are most satisfactory. For a larger portable container where manual handling is not essential, i.e. having a volume on the order of about 640 liters, an inner and outer vessel diameter of 42 inches and 48 inches, respectively, and an overall container height of 46 inches have been found to be suitable.

It is to be understood, however, that the invention is not limited to the above dimensions, and that the specific dimensions employed are determined by the conditions to which the container is to be subjected.

Any uitable means for stabilizing and centering the inner vessel 11 in the jacket 17 may be used, an example of a preferred embodiment being illustrated in FIG. 1. The inner vessel 11 is centered and held against side sway at its lower end by means of radial rods or spokes 22, made of high tensile strength, loW-heat-conductive material such as stainless steel. with a hooked outer end 24 adapted to fit into an apertured lug 25 which may be welded to the inside wall of the shell 17. A screw nipple 26 serves to join the inner end of each spoke 22 to a metal ring 27. The latter is welded to the bottom of the inner vessel 11, and provides means for adjusting the tension in each spoke to properly space one vessel within the other.

A metallic cup-shaped cap'31 is pivotally secured to the shoulder 19 by a hinge connection 32, see P16. 2, so that the cap may be swung into closed position over the lip 21, and in engagement with the shoulder 19 in the manner indicated in FIG. 1.

Each spoke is provided The intervening space 18 may be filled with a low-conductive-thermal insulation, such as highly eflicient vacuum-polished-metal surfaceand/or a suitable powder insulating material 33. For insulation filling purposes, the shoulder 19 may be provided with an opening 34, see FIG. 4, for the reception of a short base fill tube or nipple 35, which may be capped by a metal plug 36, made of brass or the like.

To reduce heat leak from the outside to the body of the liquid refrigerant in the vessel 11, the shoulder 19 is provided with an opening 33, see PEG. 3, for receiving a nipple 39 having a metal evacuation tube 40 through which the insulation space defined by the container walls may be exhausted. Depending upon the type of insulation that is employed, and the degree of insulation desired, the pressure within the insulation space should be reduced to a value below 300 microns Hg, and preferably below microns Hg. After exhaustion, the tube 40 is suitably crimped and soldered or welded to effectively seal the vacuous space 18. A filter 41 securely placed over the opening 38, prevents the migration of insulation powder during evacuation.

As shown in FIG. 1, the absolute pressure within the intervening space 18 may be further reduced and maintained at a low value by attaching an adsorbent container or blister 42 to the lower wall 12 of the inner vessel 11. The blister may contain an adsorbent material 43, for example, a zeolitic molecular sieve, either natural or synthetic such as disclosed in United States Patent 2,883,243. A filter or screen 44 provided in the blister ensures the retention of the adsorbent in the event the insulation powder is removed, it alsoprevents migration of the powder into the adsorbent blister.

Referring particularly to FIGS. 3 and 4, protection of the projecting insulation fill tube 35 and the evacuation tube 40 from damaging blows or tampering is provided by handles 45, which completely conceal the tubes from view, and thereby provide the container with a neat appearance. Each handle 45 comprises a pair of spaced, upwardly extending tubular arms 46, 47 which are welded at the lower end to the shoulder 19. Each arm is provided at its upper end with suitable registering openings for receiving a horizontal bail member 48. A cap 49 seals each of the arms 46, 47 from the entry of dust or other matter. The arm 46 is divided into two tubes, 46a and 4612, provided with complementarily threaded ends. The end portion of tube 46a is undercut to receive the lower threaded end of tube 46b, so that in assembly the outer surfaces of tube 46a and as!) are flush mounted with respect to each other. The joints of the handle 45 with the arms 46, 47 may be secured as by silver brazing to hold the handle parts in assembled position. The handle may thus be assembled without applying heat near the vacuum-tight sealed joints of tubes 35 and 40.

It will be understood that modifications and variations may be effected without departing from the spirit and scope of the novel concepts of the present invention.

What is claimed is:

1. In a portable container of the type having a vessel for holding liquefied gas surrounded by an insulating jacket, provided with a vacuum connection and an insulation filling connection, the improvement of a pair of handles for respectively concealing said connections and protecting same from damage, each of said handles comprising a pair of spaced upstanding tubular arms welded to said container, an inwardly facing opening in each of said arms adjacent the upper end thereof in registry with each other, and a horizontal bail member receivable in the openings in said spaced arms, one of said arms from each of said handles being constituted of a pair of complementarily threaded tubes, which in assembly completely conceal one of the connections on the container, respectively.

2. In a portable container of the type having a vessel for holding liquefied gas surrounded by an insulating jacket provided with a vacuum connection, the improvehandle means comprising a pair of spaced upstanding tubular arms attached to said insulating jacket, and a bail member extending between said spaced arms, one of said arms being positioned between said spaced arms, one of said arms being positioned to enclose and conceal said connection.

3. In a portable container of the type having a vessel for holding liquefied gas surrounded by an insulating jacket provided with an insulating filling connection, the improvement of hollow handle means for concealing said connection and protecting same from damage said hollow handle means comprising a pair of spaced upstanding subular arms attached to said insulating jacket, and a bail member extended between said spaced arms, one of said arms being positioned to enclose and conceal said connection.

4. In a portable container of the type having a vessel References (Zited by the Examiner UNITED STATES PATENTS 9/ 13' Stanley 2209 8/34 Badger 22010 FOREIGN PATENTS 1,104,160 11/55 France.

THERON E. CONDON, Primary Examiner.

EARLE I. DRUMMOND, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 ,191, 794 June 29, 1965 Warren E. Perkins It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 5, line 3, after "improve" insert ment of hollow line 4, after "means" insert for concealing said connection and protecting same from damage said hollow handle means line 6, for "extending" read extended lines 7 and 8 strike out "between said spaced arms, one of said arms being positioned"; line 16, for "subular" read tubular Signed and sealed this 19th day of July 1966 (SEAL) Attest:

ERNEST W. SWUJER EDWARD J. BRENNER Attesting Officer Commissioner of Patents

Claims (1)

1. IN A PORTABLE CONTAINER OF THE TYPE A VESSEL FOR HOLDING LIQUEFIED GAS SURROUNDED BY AN INSULATING JACKET, PROVIDED WITH A VACUUM CONNECTION AND AN INSULATION FILLING CONNECTION, THE IMPROVEMENT OF A PAIR OF HANDLES FOR RESPECTIVELY CONCEALING SAID CONNECTIONS AND PROTECTING SAME FROM DAMAGE, EACH OF SAID HANDLES COMPRISING A PAIR OF SPACED UPSTANDING TUBULAR ARMS WELDED TO SAID CONTAINER, AN INWARDLY FACING OPENING IN EACH OF SAID ARMS ADJACENT THE UPPER END THEREOF IN REGISTRY WITH EACH OTHER, AND A HORIZONTAL BAIL MEMBER RECEIVABLE IN THE OPENINGS IN SAID SPACED ARMS, ONE OF SAID ARMS FROM EACH OF SAID HANDLES BEING CONSTITUTED OF A PAIR OF COMPLEMENTARILY THREADED TUBES, WHICH IN ASSEMBLY COMPLETELY CONCEAL ONE OF THE CONNECTIONS ON THE CONTAINER, RESPECTIVELY.

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