Abstract
An ultra-low temperature freezer comprising an interior and a housing surrounding the interior and having an outer door. The interior comprises several cooling compartments in a stacked arrangement, each cooling compartment having an inner door. At least one upper cooling compartment has a supplementary seal for sealing its inner door compared to at least one lower cooling compartment.
Claims
1. An ultra-low temperature freezer, comprising: an interior and a housing surrounding the interior and having an outer door; wherein the interior comprises several cooling compartments with each configured to cool at ultra-low temperatures, wherein the several cooling compartments are in a stacked arrangement and wherein each cooling compartment has an inner door; and wherein at least one upper cooling compartment has a supplementary seal for sealing its inner door compared to at least one lower cooling compartment, and the supplementary seal covers a circumferential edge of the inner door of the at least one upper cooling compartment.
2. The ultra-low temperature freezer according to claim 1, wherein the supplementary seal is an integral sealing arrangement with a basic seal.
3. The ultra-low temperature freezer according to claim 1, wherein the supplementary seal is a separate, additional sealing arrangement.
4. The ultra-low temperature freezer according to claim 1, wherein the supplementary seal is arranged at the inner door of the at least one upper cooling compartment.
5. The ultra-low temperature freezer according to claim 1, wherein the supplementary seal is arranged on an inner side of the outer door facing the interior.
6. The ultra-low temperature freezer according to claim 1, wherein the supplementary seal has an extension in a horizontal direction which corresponds to a horizontal distance between the at least one upper cooling compartment, in particular its inner door, and an inner side of the outer door facing the interior or is larger than this horizontal distance.
7. The ultra-low temperature freezer according to claim 1, wherein the supplementary seal has at least one recess or gap.
8. The ultra-low temperature freezer according to claim 7, wherein the at least one recess or gap is arranged and constructed to receive a handle and/or a hinge of the inner door of the at least one upper cooling compartment.
9. The ultra-low temperature freezer according to claim 1, wherein the supplementary seal is arranged and constructed such that development of a vertical natural convection boundary layer between an upper and a lower part of the interspace in the interior between the cooling compartments and the inner side of the outer door is prevented or substantially interrupted.
10. The ultra-low temperature freezer according to claim 1, wherein a higher uniformity of temperature occurs among the several cooling compartments of the ultra-low temperature freezer than exists in a second ultra-low temperature freezer identical to the ultra-low temperature freezer excepting the supplementary seal.
Description
DESCRIPTION OF THE DRAWINGS
(1) Preferred embodiments shall now be described with reference to the attached drawings, in which:
(2) FIG. 1: shows a front view of a freezer (with the outer door in its open position) with a supplementary seal on the two topmost cooling compartments;
(3) FIG. 2: shows the inner side of an outer door of a freezer with a supplementary seal for two topmost cooling compartments;
(4) FIG. 3: shows the inner side of an outer door of a freezer with a supplementary seal for the topmost cooling compartment;
(5) FIG. 4a: shows the upper section of the inner side of an outer door of a freezer with another embodiment of a supplementary seal for the topmost cooling compartment;
(6) FIG. 4b: shows an enlarged view of a part of FIG. 4a; and
(7) FIG. 4c: shows the enlarged view of 4b from a different angle.
(8) In the figures, different embodiments of supplementary seals for ultra-low temperature freezers are shown. Identical elements or elements with substantially identical functions are indicated with the same reference signs in the drawings.
DETAILED DESCRIPTION
(9) FIG. 1 shows an ultra-low temperature freezer 10 with an interior or inner volume 14, which is encompassed by a housing, and which has an outer door 12 (shown only partly). The housing door 12 is hinged about hinges 12′ on the housing 11 and can be swung open about a vertical axis through the hinges 12′. FIG. 1 shows the freezer 10 with the outer door 12 in the open position. An outer door sealing arrangement 13 can be seen at the inner edge of the housing 11. Within the interior 14, five cooling compartments 15a,b,c,d,e are arranged in a stacked manner, i.e., the five cooling compartments 15a,b,c,d,e are arranged on top of each other. Each cooling compartment 15a,b,c,d,e is provided with an inner door which is hinged about hinges 19 and which is provided with a handle in the form of a hole or knob 18. The inner doors of the cooling compartments 15a,b,c,d,e are shown in FIG. 1 in the closed position and can be swung open about a vertical axis through hinges 19.
(10) In FIG. 1, a supplementary seal 17 is provided on the two topmost cooling compartments 15d,e. The supplementary seal 17 is provided as a separate, additional sealing arrangement, which is arranged at the inner doors of the two topmost cooling compartments. In the embodiment in FIG. 1, the supplementary seal 17 is arranged on the outer side of the inner doors of the two topmost cooling compartments 15d,e in the form of two vertical sealing strips 17b and three horizontal sealing strips 17a, covering the circumferential edges of the inner doors of the two topmost cooling compartment 15d,e. The supplementary seal 17 shown in FIG. 1, for example, may be an insulation tape approximately 2 inches wide and 3.2 mm thick.
(11) In FIG. 2 and FIG. 3, the inner side of an outer door 12 can be seen. On the outer periphery of the inner side of the outer door 12 the counterpart 13′ of the outer door sealing arrangement 13 can bee seen. In the upper part of the inner side of the outer door 12, supplementary seals 17′, 17″ are depicted.
(12) In FIG. 2, the supplementary seal 17′ is provided for the two topmost cooling compartments of an associated freezer interior (not shown in FIG. 2). The supplementary seal 17′ comprises two substantial vertical bars 17b′ and three substantially horizontal bars 17a′ arranged and positioned to cover the circumferential edges of the inner doors of the two topmost cooling compartments. The supplementary seal 17′ is substantially in the form of two rectangles.
(13) In FIG. 3, the supplementary seal 17″ is provided for the topmost cooling compartment of an associated freezer interior (not shown in FIG. 3) only. The supplementary seal 17″ shown in FIG. 3 comprises two substantially vertical bars 17b″ and two substantially horizontal bars 17a″ to cover the circumferential edge of the inner door of the topmost cooling compartment. The supplementary seal 17″ has a substantially rectangular shape.
(14) Both supplementary seals of FIG. 2 and FIG. 3 are provided at the inner side of the outer door 12, which, in its closed position, faces the associated interior of the freezer. Both supplementary seals 17′ and 17″ of the embodiments shown in FIG. 2 and FIG. 3 have an extension in a horizontal direction perpendicular to the inner surface of the outer door which, in its non-compressed state with the outer door 12 in the open position as shown in FIG. 2 and FIG. 3, is larger than a horizontal distance between the topmost or the two topmost cooling compartments, in particular their inner doors, and the inner side of the outer door 12 in its closed position. Due to this large horizontal extension, the supplementary seals 17′, 17″ will contact the inner doors of the one or two topmost cooling compartments when the outer door 12 is in its closed position. Thereby, the supplementary seals 17′, 17″ cover the circumferential edges of the inner doors of the one or two topmost cooling compartments and thus improve the sealing of these doors. Additionally, the supplementary seals 17′, 17″ substantially interrupt development of a vertical natural convection boundary layer between an upper and a lower part of an interspace in the interior between the cooling compartments and the inner side of the outer door in the closed position of the door.
(15) As can be seen in FIGS. 4a,b,c, a supplementary seal 17′″ is provided which is similar to the supplementary seal 17″ shown in FIG. 3. Also the supplementary seal 17′″ in FIG. 4a,b,c is arranged for sealing the inner door against the cooling compartment of the topmost cooling compartment of an associated freezer interior (not shown in FIGS. 4a,b,c). The supplementary seal 17′″ comprises two substantially horizontal bars 17a′″ and two substantially vertical bars 17b″. The supplementary seal 17′″ has two recesses or gaps 17c′″ located in the two horizontal bars 17b′″. The recesses or gaps 17c′″ are arranged and constructed to receive a handle and/or a hinge of the inner door of the topmost cooling compartment. Although the supplementary seal 17′″ shown in FIGS. 4a,b,c does not fully cover the circumferential edge of the inner door of the topmost cooling compartment when the outer door 12 is closed, the coverage is sufficient to increase the sealing of the inner door of the topmost cooling compartment to enhance temperature uniformity within the freezer.
(16) For example, the supplementary seals 17′, 17″, 17′″ may comprise a coated silicon sponge as a sealing material and a uPVC (unplasticized polyvinyl chloride) channel as an insulation material and as a means to mount the silicon sponge on the inner surface of the outer door. The uPVC channel could be secured to the inner surface of the outer door using hot melt glue or fasteners.
(17) As can be seen from the embodiments, a variety of cost-effective and practical embodiments to provide an ultra-low temperature freezer with a supplementary seal on at least one upper cooling compartment can be provided to improve the sealing of the at least one upper cooling compartment and thereby improving temperature uniformity within the freezer and in particular across the different cooling compartments.
