DE2739871A1 - FREEZER WITH LOCK - Google Patents

Description

TlEDTKE "BOHLING" KlNNE - GROUP

Dipl.-Chem. G. Buehling

97 ^ 9871 Dipl.-lng. R. Kinne

'Dipl.-lng. P. Grupe

Bavariarlng 4, P.O. Box JD

8000 Munich 2

Tel .: (0 89) 5396 53 Telex: 5-24845 tipat cable: Germaniapatent monks

September 5, 1977 B 8428 / ICI case Ps.29Ο62 / 2926Ϊ

Imperial Chemical Industries Limited London, UK

Freezer with lock

The invention relates to a freezer with a lock.

The use of freezers for food storage has spread rapidly in the household in recent years. These freezers work so that the food is kept at temperatures of less than -10 ° C and preferably below -15 ° C. Compliance with this large temperature difference between the operating and ambient temperatures requires considerable electrical energy consumption. Even though it is used to a limited extent for freezing fresh foods on the spot, such as home-grown vegetables becomes the bulk of the stored food Purchased as prepackaged, frozen goods in specialty frozen food stores. These usually called frozen food centers designated shops offer the goods in the usual household freezers, which are isolated from one Chest and a lid hinged to the top of the chest. To the contents of the normal household freezer to check, the cap must be lifted. To increase sales and the goods To effectively offer buyers, it is customary to use the closure

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Dresdner Bank (Munich) Account 3B3> 844 PostachMk (Munich) Account 670-43-804

Jl ^{B 8428}

"* '? 739871

to leave the lid open. Mostly do the increasing ones Electrical energy costs ultimately make this practice costly because the heat losses under these conditions are significant have increased compared to the cost of a normally closed freezer. To reduce operating costs at the same time To create an easily visible offer to lower the contents of the freezer, an attempt was made to seal lids made from one-piece sheets of transparent thermoplastics. These were to reduce operating costs partially successfully usable, but the view was due to the large temperature difference between the lid and the contents of the freezer resulting from condensation on the underside of the lid. A chest freezer cover has now been created which substantially overcomes these problems.

Accordingly, a freezer was created which consists of a closure made of a pair of rigid, transparent plates consists of thermoplastic material, which on its periphery to form a peripheral flange to delimit a double-walled closed shell are connected to each other.

The invention also provides a double-walled closure for a freezer from a pair of solid, thermoplastic sheets of thermoplastic material which are connected to one another at their periphery to form a peripheral flange which defines a double-walled closed envelope.
30th

Preferably, the walls of the closure are spaced from one another over the greater part of their surface by at least 10 mm. In the simplest embodiment, one of the plates forming the shell is essentially one flat and with its circumference with the circumference of a second, dish-shaped plate of suitable dimensions tied together. The KUlIe can alternatively consist of two,

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molded plates joined at its periphery, the shape being such that an inner molded plate is received in the space defined by an outer molded plate and the joined peripheral surfaces form a planar base.

The application of the invention results in a much larger one Saving in operating costs than achieved with one-piece sealing caps made of transparent plastic and, there the condensation is significantly reduced, the vision problem is much improved. The excellent view allows both both the buyer and the refill staff can check the contents of a freezer at a glance. Unnecessary opening the cap and the consequent increases in operating costs are reduced to a minimum .

Preferably, the closure is designed so that a pair of plates are substantially parallel with a sufficient spacing from one another are arranged to achieve good thermal insulation properties.

In general, an optimal operation will be at a distance between 10 mm and 40 mm preferably 15 to 30 now reached.

The double-walled latch can be attached to the freezer by any suitable hinge for easy opening and closing. The hinge is usually attached to the flange of the sealed closure. Preferably the edge of the sealed closure is complete with a. Metal frame surrounded so that the risk of damaging the edges of the closed envelope is low. The hinge is attached to the metal frame.

Alternatively, suitable closures have been created at

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which eliminates the need to enclose the sealed edge of the closure with a metal frame. Surprisingly, the double shell of the closed envelope creates a sufficiently strong structure to make the metal border superfluous, as a result of which the costs of the closure are significantly reduced. When the metal framing is not used, the hinge is preferably attached to the closure by means of fasteners, such as screws, which pass through the walls of the double-walled envelope rather than through the flanged skirt. In such an arrangement, it should be noted that the separate walls are subjected to little or no stress from the screws. This is achieved simply by inserting pieces of material that fill the gap between the walls and prevent relative movement of the walls when the screws are tightened.

Accordingly, a freezer was additionally provided with a closure which has inner and outer molded transparent thermoplastic panels which are spaced over the greater part of their surface and whose peripheral surfaces are connected to one another to form a peripheral base part, the inner and outer extending from the peripheral base part Take up spaced peripheral walls and fasteners between them to attach the closure to hinges of the freezer. Suitably, such a double-walled closure is so constructed that the walls by which the hinge is attached are parallel and at right angles to the flange. Other arrangements with suitable Ver reinforcement and spacers are possible.

The hinge used can be a spring-loaded hinge, but the comparatively relatively low weight of the closure according to the invention allows it conventional closures for freezers the use of cheaper hinges of lighter construction.

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Suitable double-walled, flanged, sealed envelopes can be made in a known manner. A method for the semi-automatic large-scale production of some embodiments of such units is described in GB-PS 1 38 ^ 885. In this case, the mixture is heated at a described method, a pair of thermoplastic sheets one of which is provided with an opening - to soften the plates prior to assembly, the disc drags without opening of the aperture plate through the use of pressure or vacuum away until the solid Plate comes into contact with a supporting edge and subsequently creates a rapid pressure equalization on each side of the drawn part of the plate in order to bring the drawn part into a substantially parallel position to the undrawn plate. Prior to heating the surfaces of the plates that have been brought by the chucking operation in mutual contact, are provided with an activated under heat and pressure adhesive. By using a solution of a low molecular weight polymethyl methacrylate in a methyl methacrylic monomer , a very satisfactory bond is obtained when the thermoplastic sheets are made of polymethyl methacrylate. This is applied to the plate surfaces over which a mutual bond is required and dried until a non-sticky film is formed. When the panels are softened by heat and braced together, a very effective bond is formed.

Any other method can be used to form the flanged sealed envelope.

^ The closed envelope can e.g. be produced by that by means of the usual WMrmeformverfahren first a forms a single plate so that it forms a bowl-shaped object with a flat surface surrounded by a flange Surface, and then a second flat plate with glued to the flange so that a sealed completed Shell is formed with substantially flat walls. GB-PS 1 414 747 describes a particular method

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for the production of a double-walled, suitable for a caravan Window. The method described can be suitable for the production of the closures according to the invention.

At least one of the plates forming the closures can additionally be molded to create an integral handle or grip hole.

The invention is explained below on the basis of exemplary embodiments explained in more detail with reference to the drawing.

It shows:

Fig. 1 shows a cross section through an inventive Closure which forms a closure lid for a freezer and is encompassed by a metal frame. Fig. 2 shows a further embodiment in which the hinge of the freezer on the closure by means of spaced walls is attached and the metal frame is omitted.

In Fig.l is a generally designated by the reference number IO double-walled unit made from a pair according to the method of GB-PS 1 384 885 made of polymethyl methacrylate plates 11 and 12 by means of a metal frame 13 which surrounds the edges of the double-walled unit. The metal frame 13 has a generally U-shaped cross section with a recessed extension 14 for receiving a fastening strip 15 of a flexible sealing element 16. The flexible sealing element 16 is arranged so that it forms a seal with the wall 17 of a freezer when the closure lid is closed. The metal frame 13 is provided one side of the frame with stable metal pieces 18 along, so that an attached to the freezer spring-loaded hinge (not shown) can be attached to cover the framed closure.

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2, a general reference number 20 is used double-walled unit formed by being separated two plates 21, 22 made of polymethyl methacrylate and glued together to form a flange, of the inner and outer spaced peripheral walls 24 and 25 extend. Reinforcement pieces 26 made of polymethyl methacrylate are to be filled of the gap between that part of the walls to which the hinge is to be attached. The pieces 26 are inserted between the walls during the assembly of the double-walled fastener. A spacer plate 27 and a Clamping plates 28 are provided in alignment with the reinforcement piece 26 on each side of the double-walled fastener. The assembly is on a piece of aluminum 29 which forms part of a hinge system (not shown) attached to the freezer forms, attached by means of screws 30, through provided in the aluminum piece, with holes in the spacer plate 27, the reinforcement piece 26 and the clamping plate 28 are aligned holes and are fastened with nuts 31. The plate 22 is provided with a protrusion 32 on the side of the closure opposite the hinge. Of the protrusion 32 is provided in the middle of its length with a lip 33, which when lifting or lowering the closure cap serves as a handle. A sealing strip 34 is on the flange 23 of the closure for sealing contact with the top surface glued to the wall 35 of the freezer.

While the closures according to the invention are particularly suitable for Creation of end covers for freezers are suitable, the invention is not limited to such end covers, but can also be used for the doors of vertical refrigerators. The closures according to the invention are for every size of normally available freezers with opening dimensions of about 60 to 120 cm in width and about 120 to 240 cm in length usable.

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Polymethyl methacrylate is considered a thermoplastic material for the present invention because of its excellent clarity, extremely suitable for good impact and scratch resistance. Small proportions of comonomers can be found in the methyl methacrylate to be available. Other suitable transparent thermoplastics are polymers and copolymers of vinyl chloride, styrene, Polycarbonates and cellulose acetate butyrates. The surface hardness of these materials, especially that of polymethyl methacrylate, are able to withstand normal use, but can occasionally be polished to remove from scratches may be necessary. The hardness of the surface can be determined by the use of known surface treatments, that provide abrasion resistance is improved will.

The present invention has provided a freezer with a pair of transparent, rigid sheets of thermoplastic Material having closure created, the plates together to form a double-walled Sheath are formed with a peripheral flange. Of the Closure may be contained in a surrounding metal frame or, preferably, be frameless, being spaced apart by the Fastening means for attaching the closure to hinges are provided, which go to the standing walls of the shell.

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Claims (8)

TlEDTKE - BüHLING - KlNN: = - GnUPE Dipl.-Chem. G. Bühling Dipl.-Ing. R. Kinne 27 39871 Dipl.-Ing. P. Grupe Bavarian ring 4, P.O. Box 20240! 8000 Munich 2 Tel .: (0 89) 53 96 53 Telex: 5-24845 tipat cable: Germaniapatent Mancher September 5, 1977 B 8428 / ICI case Ps.29062 / 29265 Claims / Ί. ^ Freezer with a closure, characterized in that the closure consists of a pair of solid, transparent plates (11,12,21,22) made of thermoplastic material, which on its periphery to form a peripheral flange (23) to delimit a double-walled enclosed space are interconnected. 2. Freezer according to claim 1, characterized in that the walls of the closure run parallel to one another essentially over the greater part of their area and have a distance of at least 10 mm and less than 40 mm. 3. Freezer according to claim 1 and 2, characterized in that the closure is formed of two shaped plates (11,12,21,22), wherein an inner shaped plate is received in the space of an outer shaped plate, and the bonded circumferential surfaces form a flat perimeter base . 809812/0683 original inspected Dresdner Bank (Munich) Account 3199 644 Poatach «* (Munich) KIo. 670-43-BtM -2- B 8428 4. Freezer according to one of claims 1 to 3, characterized in that the closure is in a surrounding space Frame is included. 5. Freezer according to claims 1 to 3, characterized in that that the closure has inner and outer molded, transparent, thermoplastic plates (21,22), which have a distance from one another over the greater part of their surface and their peripheral surfaces to one another Forming a circumferential base part (23) are glued, which has inner and outer circumferential walls (24, 25) that are spaced apart, which extend from the peripheral base part (23) and fastened between them reinforcement pieces (26) for fastening elements (30,31) to attach the lock to the hinges of the freezer. 6. Freezer according to claim 5, characterized in that the inner and outer spaced apart from the Circumferential base part outgoing walls (24,25) are parallel to each other and at right angles to the base part. 7. Freezer according to claim 5 and 6, characterized in that the closure on hinges of the freezer is fastened by means of screws (30), which through the peripheral walls (24,25) the reinforcing pieces (26) and plates (27,28) which are located on the outer walls of the closure and aligned with the reinforcement pieces (26). 8. Freezer according to one of claims 1 to 7, characterized in that at least one plate of the closure is formed to create a one-piece handle with a lock. 809812/0683