WO2018202365A1

WO2018202365A1 - Refrigerator comprising a plastic inner lining

Info

Publication number: WO2018202365A1
Application number: PCT/EP2018/058194
Authority: WO
Inventors: Hakan OZKAN; Emre DEMIRTAS; Serhat CATALORMAN; Sebehattin SEN
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2017-05-03
Filing date: 2018-03-29
Publication date: 2018-11-08
Anticipated expiration: 2019-11-03
Also published as: EP3619485B1; TR201706505A3; EP3619485A1; PL3619485T3

Abstract

The present invention relates to a refrigerator (1) comprising a body (2), at least one door (3), at least one cooler/freezer compartment (4) in which the food products and beverages are placed, an inner lining (5) made of plastic material by way of extrusion, forming the inner surfaces of the body (2) and the doors (3) facing the compartments (4), an outer wall (6) forming the outer side of the body (2) and the doors (3), and an insulation volume (7) provided between the inner lining (5) and the outer wall (6), into which polyurethane (PU) is injected.

Description

REFRIGERATOR COMPRISING A PLASTIC INNER LINING

The present invention relates to a refrigerator in which plastic material is used in producing the inner lining of its body. In production of inner linings of refrigerator body and doors, quadrilateral plates made of polystyrene (HIPS - High Impact Polystyrene) material by way of extrusion, are used, and the net shape to said plates is given by thermoforming. In the refrigerator body, generally polyurethane is used as heat insulation material. Polyurethane expands and solidifies during production once it is injected into the refrigerator body. During this process, pockets form inside the polyurethane in case polyurethane is not distributed homogeneously, leading in time to collapses on the body walls contacting the polyurethane. As a solution to this problem, state of the art international patent application no. WO2013038003 discloses a cooler comprising a body having an inner lining, an outer wall, an insulation volume provided between the inner lining and the outer wall and an insulation material filled into the insulation volume, in which the pockets formed within the insulation material are eliminated. In said patent application, a net enabling homogeneous distribution of polyurethane is placed on the surface of the inner lining of the refrigerator facing the insulation volume, but said netting implementation causes a high increase in refrigerator production costs. The “corona” process used to adapt the inner lining with the polyurethane in terms of homogeneous distribution of the polyurethane, is also an application increasing the costs.

The aim of the present invention is to realize a refrigerator having an inner lining whose surface roughness is increased during production so as to improve adherence to the polyurethane in the insulation volume within the refrigerator body.

In the refrigerator realized to achieve the aim of the present invention, the inner linings of the body and the doors are made of plastic plates by way of extrusion. The inner lining has a three layered structure, and comprises an upper layer made of glossy polystyrene based plastic material, forming the inner surface of the inner lining facing the compartments, an interlayer resistant to the chemicals in polyurethane, and a lower layer contacting the polyurethane injected in the insulation volume between the inner lining and outer wall of the body, wherein the roughness of its surface contacting the polyurethane is increased by adding a chemical foaming agent to the polystyrene based main material. The foaming agent added during production of the inner lining to the polystyrene based main material of the lower layer in order to decrease weight, is transitioned to the gaseous phase on the surface of the lower layer contacting the polyurethane, thereby enabling roughening of the surface of the lower layer facing the insulation volume due to the effect of the foaming agent.

The refrigerator realized to achieve the aims of the present invention is illustrated in the accompanying drawings, wherein:

Figure 1 is a schematic view of a refrigerator.

Figure 2 is a schematic view of the three layered inner lining structure provided in the refrigerator of the invention.

The elements in the figures are numbered individually and the correspondence of these numbers are given hereinafter.

Refrigerator
Body
Door
Compartment
Inner lining
External wall
Insulation volume
Upper layer
Interlayer
Lower layer

The refrigerator (1) comprises a body (2), at least one door (3), at least one cooler/freezer compartment (4) in which the food products and beverages are placed, an inner lining (5) made of plastic material by way of extrusion, forming the inner surfaces of the body (2) and the doors (3) facing the compartments (4), an outer wall (6) forming the outer side of the body (2) and the doors (3), and an insulation volume (7) provided between the inner lining (5) and the outer wall (6), into which polyurethane (PU) is injected.

In the refrigerator (1) of the invention, the inner lining (5) has a three layered structure, and comprises an upper layer (8) made of glossy polystyrene based plastic material, forming the inner surface of the inner lining (5) facing the compartments (4), an interlayer (9) made of polystyrene based plastic material of high resistance to the chemicals in polyurethane, and a lower layer (10) provided at the insulation volume (7) side, contacting the polyurethane injected in the insulation volume (7), its surface contacting the polyurethane being roughened by adding a chemical foaming agent to the polystyrene based main material.

The chemical foaming agent used in weight reduction, is added during production to the polystyrene based plastic material forming the lower layer (10). When used in predetermined proportions, the chemical foaming agent transitions to the gaseous phase within a specific temperature range and forms pockets in the polystyrene based main material. Roughening of the lower layer (10) of the inner lining (5) contacting the polyurethane injected in the insulation volume (7), improves adherence of the polyurethane to the plastic material and enables homogeneous distribution of the polyurethane in the insulation volume (7). The chemical foaming agent also enables reducing the weight of the lower layer (10) and therefore of the inner lining (5), and less raw materials are used compared to the state of the art.

In the embodiment of the invention, the foaming agent added during production of the inner lining (5) to the polystyrene based main material of the lower layer (10), is transitioned to the gaseous phase on the surface of the lower layer (10) contacting the polyurethane, so as to enable roughening of the surface of the lower layer (10) facing the insulation volume (7).

In the embodiment of the invention, foaming agent is added during production to the polystyrene based main material of the lower layer (10) in the ratio of 2 - 4%. The lower layer (10) roughened using the foaming agent has a thickness in the range of 90-150 μm, and the surface of the lower layer (10) contacting the polyurethane has a roughness value in the range of Ra: 30 - 40 μm ( in the state of the art, said roughness value is identified to be in the range of Ra: 1 - 1.5 μm ).

In the embodiment of the invention, the glossy polystyrene based upper layer (8) has a thickness in the range of 90 - 150 μm, and the polyurethane chemicals resistant polystyrene based interlayer (9) has a thickness in the range of 2.5 - 4.6 mm.

The refrigerator (1) of the invention eliminates the necessity of the netting implementation used for homogeneous distribution of the polyurethane in the insulation volume (7), and the “corona” process used to adapt the polystyrene material to the polyurethane, providing cost advantage. The polyurethane is distributed in the insulation volume (7) homogeneously and without pockets. Collapses are prevented from forming on the outer wall (6) of the body (2).

Claims

A refrigerator (1) comprising a body (2), at least one door (3), at least one cooler/freezer compartment (4) in which the food products and beverages are placed, an inner lining (5) made of plastic material by way of extrusion, forming the inner surfaces of the body (2) and the doors (3) facing the compartments (4), having an upper layer (8) made of glossy polystyrene based plastic material, and an interlayer (9) made of polystyrene based plastic material of high resistance to the chemicals in polyurethane, an outer wall (6) forming the outer side of the body (2) and the doors (3), and an insulation volume (7) provided between the inner lining (5) and the outer wall (6), into which polyurethane (PU) is injected,

characterized by the inner lining (5) comprising a lower layer (10) provided at the insulation volume (7) side of the inner lining (5), contacting the polyurethane injected in the insulation volume (7), its surface contacting the polyurethane being roughened by adding a foaming agent to the polystyrene based main material.
A refrigerator (1) according to claim 1, characterized by the foaming agent added to the polystyrene based main material of the lower layer (10), and transitioned to the gaseous phase on the surface of the lower layer (10) contacting the polyurethane.
A refrigerator (1) according to claim 1 or 2, characterized by the foaming agent added during production to the polystyrene based main material of the lower layer (10) in the ratio of 2-4%.
A refrigerator (1) according to claim 1 or 2, characterized by the lower layer (10) roughened using a foaming agent, having a thickness in the range of 90 - 150 μm.
A refrigerator (1) according to claim 1 or 2, characterized by the lower layer (10) whose surface contacting the polyurethane has a roughness value in the range of 30 - 40 μm.