DE60108766T2 - REINFORCED LID FOR ELECTRIC HOUSEHOLD APPLIANCES AND MANUFACTURING METHOD - Google Patents

Abstract

The lid reinforcements consist of parallel equidistant strips (1) perpendicular to its plane, which are supported on the inner face with a tab (2), provided with a plastic coating (3) and supported in brackets (4). The lid structure comprises: a plastic panel (5) clad with melamine or decorated film (6), reinforced with strips (1) and a frame (7) clasping it at its edges. The manufacturing procedure comprises: Unrolling (8) the strip, Straightening (9), Profiling (10), Induction preheating (11), Shearing (12), Robotized transfer (13) to injection machines (14), Robotized feeding (15) of melaminized paper or decorated film to the injection machines (14), Overinjection of reinforcement coating, Withdrawal of reinforced panels by the robots (15). Overinjection of the frame in another injection machine. <IMAGE>

Description

Task of invention

The The present invention relates to a reinforced cover for electrical Domestic appliances, which optimal functional suitability, both from the point of view of mechanical Strength as well as the protection the humid environment in which he has to work, with little Combined manufacturing costs.

The Invention is particularly suitable for producing such covers, which the upper closure of Training household washing machines. The invention also relates a method for producing such a lid.

background the invention

The best known and most widely used structure for washing machine lids is made of a hardboard, which with melamine paper lined with adhesives or resins with a synthetic resin frame is connected, either directly or between two frames, the upper one and the bottom one.

In In the first case, the plate and the frame are usually by adhesive beds connected on each side of the plate, so that these edges, which not lined with melamine, protect from moisture.

In later Case, the two frames surrounding the plate are ultrasonically welded while their outer edge protected by a rubber seal is to make it leak-proof.

In any case would the most durable and therefore most desirable solution in the replacement of the cover made of hardboard, whose main component (Wood chips) is highly hygroscopic (see, for example, DE-A-196 01 124), resulting in a permanent risk of quality degradation due to the inevitable Presence of moisture in washing machines leads.

To For this purpose, injection-molded plastic lids were used, however except for thermoplastic materials, which have hindrances in relation to the competition and which demanded by the manufacturers of household electrical machines meet technical requirements, no satisfactory results delivered.

description the invention

Of the Purpose of the invention, which justifies the object of this patent is in the avoidance of using hardboard in washing machine lids associated disadvantages and their replacement by other suitable materials, which are able to meet the technical standards fulfill.

• a) mechanisch: diese führen dazu, daß einem möglichen Brechen des Deckels zuvorgekommen und dieses verhindert wird, insbesondere aufgrund einer großen oder sogar unzulässigen Last, während sich die Waschmaschine in Betrieb befindet, beispielsweise aufgrund der Tatsache, daß jemand auf den Deckel steigt, in welchem Fall die Zerstörung des Deckels durch eine mögliche Verletzung der Person begleitet werden würde. Die erforderliche mechanische Stärke wird daher auf 1000 N in einem 20 × 20 cm großen zentralen Bereich des Deckels und auf 800 N an den Kanten festgesetzt.
• b) chemisch: Der notwendige Gebrauch von Reinigungschemikalien (Reinigungsmitteln, Bleichen, Weichmachern) in den Waschmaschinen begründet das technische Erfordernis nach einer Beständigkeit darauf, was aus vorausschauenden und Sicherheitsgründen des weiteren auf andere Chemikalien (Ammonium, Alkohol) und sogar auf Getränke (Frucht- und Gemüsesäfte, alkoholische Getränke, Cola) angewendet wird.

There are basically two types of requirements:

• a) mechanical: these lead to a possible breakage of the lid being prevented and prevented, in particular due to a large or even undue load while the washing machine is in operation, for example due to the fact that someone gets on the lid, in In which case the destruction of the lid would be accompanied by a possible injury to the person. The required mechanical strength is therefore set at 1000 N in a 20 × 20 cm central area of the lid and at 800 N at the edges.
• (b) chemical: the necessary use of cleaning chemicals (detergents, bleaches, plasticisers) in washing machines justifies the technical requirement for resistance to what, for reasons of foresight and safety, is further limited to other chemicals (ammonium, alcohol) and even to beverages (fruit juice); and vegetable juices, alcoholic beverages, cola).

The resistance across from the attack of all of these products requires that Appearance of the lid after a contact time of at least 16 hours unchanged should stay.

These Basic requirements are supplemented by various others: thermal (70 ° C for 7 days), environmental (recycling, absence of formaldehydes), climatic, Etc.

The Compliance with all These requirements, unlike the mechanical one, can be achieved by the choice of the right raw material. However, resist these materials are not themselves subject to the imposed load conditions, in particular not with the limitation of dimensions, which by the maximum price the competitive costs is imposed.

The The present patent application claims the creation of washing machine lids metal reinforcements, about their mechanical strength over the to increase the minimum required values.

The Design of the reinforcements considered the fact that the Load that must be withstood by the lid (1000 N in the middle area) is directed vertically and inwards, so that to Compensation a principle similar the mechanical performance of reinforced concrete is used, where the reinforcements be used in areas in which the lid of a load-bending load suspended is.

by virtue of these considerations the reinforcements exist from thin Steel strips, which are parallel in vertical planes to the inside of the lid arranged to each other and the lid pivot axis at equal distances are.

At have their end of attachment to the inner level of the lid these bands small orthogonal support strips while over-molded with a plastic coating are and against lateral deformation (tipping over) by means of brackets along protected on both sides are.

The Structure of the lid comprises: a plate with low mechanical power, formed in a molding process was and on her upper and outer sides coated with a sheet of melamine that is heat-activated Adhesive glued or with a transparent film on the inside Side, which during the forming process is attached, wherein the plate by means of metal moldings as described above reinforced is and the unit with a high performance plastic frame that enclosing them by their edges, overmolding them is.

• – Abwickeln der Stahlbandrollen bei gleichzeitiger Verwendung von 4 Rollen,
• – gleichzeitiges Ausrichten der vier Bänder in einem Walzenzug mit verstellbarer Position,
• – Profilieren der Bänder in zwei Anfangs- und Endzügen für die ununterbrochene Formgebung der Deckelverstärkungen,
• – Vorwärmen der vier geformten Bandstränge, vorzugsweise durch Induktion, um einen übermäßigen Temperaturunterschied während des Einspritzens zu verhindern, der zum Abkühlen und abrupten Aushärten des eingespritzten Kunststoffs bei Kontakt mit dem Metall führen würde und die relative Bewegung zwischen beiden Materialien hindern würde, die während des Einspritzverfahrens der verstärkenden Beschichtung notwendig ist,
• – gleichzeitiges Zuschneiden der vier geformten Bandstränge auf das benötigte Maß, so daß bei jedem Pressenhub vier Verstärkungen hergestellt werden,
• – Fördern der vier vorgewärmten Verstärkungen mittels eines Portalroboters, der von zwei Einspritzmaschinen geteilt wird, diese mit seinen Greifern festhält und sie in den Formen anordnet,
• – automatisches Beschicken von melaminiertem Papier oder transparentem dekoriertem Film mittels individueller Roboter,
• – Überspritzen zur Ausbildung der Platte und Beschichtung der Verstärkungen,
• – Entladen der Einspritzmaschinen und Herausnehmen der verstärkten Platten mittels des gleichen Beschickungsroboters, welcher sie an eine andere Einspritzmaschine zur Überspritzung des Rahmens liefert, wobei der Deckel ausgebildet wird.

The method of manufacturing the reinforced covers having the technical characteristics described above has the following sequential operations:

• Unwinding of the steel strip rolls with simultaneous use of 4 rolls,
• Simultaneous alignment of the four belts in an adjustable-position compactor,
• Profiling of the bands in two initial and final courses for the continuous shaping of the lid reinforcements,
• Preheating the four formed strip strands, preferably by induction, to prevent excessive temperature differential during injection which would result in cooling and abrupt curing of the injected plastic upon contact with the metal and would hinder relative movement between both materials during the injection molding process Injection process of the reinforcing coating is necessary
• Simultaneous cutting of the four formed strip strands to the required dimension so that four reinforcements are produced on each press stroke,
• - conveying the four preheated reinforcements by means of a gantry robot divided by two injection machines, holding them with his grippers and arranging them in the molds,
• Automatic loading of melaminated paper or transparent decorated film by means of individual robots,
• Overmolding to form the plate and coating of the reinforcements,
• Unloading the injection machines and taking out the reinforced plates by means of the same loading robot, which supplies them to another injector for overmolding the frame, wherein the lid is formed.

at an improved embodiment the structure of the lid are the plastic plate with less Performance and over-molded Frame that encloses its edges, replaced by a single piece, which forms both the plate and the frame, from a (recycled) low-power material molded and completely with a heat-formed transparent film on its inner side for mounting on the sole, the plate and the frame forming Part is coated.

When a result of unifying the plate and the frame in a single part may be the last injection machine for overspray the frame in the manufacturing process of the cover account, since the lids from the two parallel injection machines in one already finished state come.

In another improved embodiment The lid structure is the plastic plate with low power and the oversprayed Frame enclosing them by their edges, by a single piece, which the plate and the frame is formed, replaced, which made of new material is poured (the first time in use), with the result that the Plate corresponding part of the single piece with melaminiertem paper coated with heat activated adhesive on the Top of the lid plane is attached.

As in the aforementioned case, for example, as a result of Unify plate and frame into a single piece of the last injection machine to overspray of the frame in the manufacturing process of the cover, since the lids the two parallel injection machines in one already finished state to be left.

In another improved version of the lid structure, the low temperature plastic plate and the overmolded frame are Mo the arrangement of the plate / frame separated, so that the latter, instead of the plate at its edges, is placed on this along its outer edges, while both parts by an around the circumference of the lower or inner surface of the plate running adhesive bed between its edge and the inner side of the frame walls are fixed, wherein the plate is covered with melaminiertem paper, which is fixed with heat-activated adhesive on top of the cover plate.

In a last improved version of the lid structure are the plate Made of (recycled) low-power plastic and over-molded Frame of unused material by modifying the arrangement the plate-frame unit separated from each other, so that the latter instead of enclosing the plate at its edges, on its upper peripheral area is attached, with both parts through an ultrasonic welder along the upper or outer side the plate between the edge and the inner side of the patch Part of the frame are connected, the panel with melaminiertem Paper is clad on which with heat-activated adhesive on the top of the lid plane is attached.

description the drawings

Around to complement the description of the invention and to help the formal, structural and functional characteristics of their task to understand drawings are attached which schematically different aspects of a preferred embodiment of the "reinforced lid for electrical domestic appliances and the process for its preparation ", which is the object of this patent form.

In the aforementioned drawings shows:

1 a sectional view in a vertical plane of one of the vertices of the reinforced lid,

2 a sectional view of the shape and design of the metal reinforcements

3 a representation of the distribution plan of the work elements included in the development of the claimed method,

4 4 is a vertical sectional view of the structure of one of the vertices of the improved lid according to another embodiment;

5 a cross-section of the shape and the design of the metal reinforcements in the improved lid according to the preceding figure,

6 4 is a vertical sectional view of the structure of one of the vertices of the improved lid according to another embodiment;

7 a cross-section of the shape and the design of the metal reinforcing elements of the improved cover of the preceding figure,

8th 1 is a vertical sectional view of one of the vertices of the improved cover according to another embodiment;

9 a sectional view of the shape and the design of the metal reinforcements of the improved cover of the preceding figure,

10 4 is a vertical sectional view of the structure of one of the vertices of the improved lid according to another embodiment;

11 a sectional view of the shape and the design of the metal reinforcements in the improved cover according to the preceding figure.

preferred embodiment the invention

Around clear the nature and scope of the advantageous application of the "reinforced lid for electrical domestic appliances and the method for its production ", which represent the object of the invention, to show its structure and manufacturing process with respect to the drawings described below.

The reinforcements are made of thin strips ( 1 ) made of steel, which are arranged perpendicular to the inside of the lid, parallel to each other and to its pivot axis and at equal intervals and at its end of attachment to the inner level of the lid a small orthogonal Auflagerstreifen ( 2 ) while the aforementioned strips ( 1 ) with a plastic coating ( 3 ) are overmolded and protected from lateral deformations (tipping over) by means of clamps along both sides thereof.

Their structure comprises: a plate with low mechanical performance, which is formed in the molding process and at its upper or outer side with a melamine web ( 6 ), which is glued with a heat-activated adhesive or is attached to a transparent film decorated on the inside during the molding process, the board being formed with metal moldings ( 1 ) and the unit is fitted with a high-performance plastic frame ( 7 ), which encloses them at their edges, is overmolded.

• – Abwickeln (9) der Stahlbandrollen bei gleichzeitiger Verwendung von vier Rollen,
• – gleichzeitiges Ausrichten der vier Bänder in einem Walzenzug (9) mit verstellbarer Position,
• – Profilieren der Bänder in zwei Anfangs- und Endzügen (10) für die ununterbrochene Formgebung der Deckelverstärkungen,
• – Vorwärmen der vier geformten Bandstränge in einer Induktionseinheit (11), um einen übermäßigen Temperaturunterschied während des Einspritzens zu verhindern, der zum Abkühlen und abrupten Aushärten des eingespritzten Kunststoffs bei Kontakt mit dem Metall führen würde und die relative Bewegung zwischen beiden Materialien hindern würde, die während des Einspritzverfahrens der verstärkenden Beschichtung notwendig ist,
• – gleichzeitiges Zuschneiden der vier geformten Bandstränge auf das benötigte Maß, so daß bei jedem Pressenhub 4 Verstärkungen hergestellt werden,
• – Fördern der vier vorgewärmten Verstärkungen mittels eines Portalroboters (13), der von zwei Einspritzmaschinen (14) geteilt wird, diese mit seinen Greifern festhält und sie in den Formen anordnet,
• – automatisches Beschicken von melaminiertem Papier oder transparentem dekoriertem Film mittels individueller Roboter,
• – Überspritzen zur Beschichtung der Verstärkungen,
• – Entladen der Einspritzmaschinen und Herausnehmen der verstärkten Platten mittels des gleichen Beschickungsroboters (15), welcher sie an eine andere Einspritzmaschine zur Überspritzung des Rahmens liefert, wobei der Deckel ausgebildet wird.

The manufacturing process of the covers involves the following sequential operations:

• - Transact ( 9 ) of steel strip rolls with simultaneous use of four rolls,
• Simultaneous alignment of the four belts in a compactor ( 9 ) with adjustable position,
• - Profiling the bands in two initial and final trains ( 10 ) for the continuous shaping of the lid reinforcements,
• Preheating the four shaped strip strands in an induction unit ( 11 ) to prevent excessive temperature differential during injection, which would lead to cooling and abrupt curing of the injected plastic upon contact with the metal and would hinder relative movement between both materials necessary during the injection process of the reinforcing coating.
• - Simultaneous cutting the four shaped strip strands to the required size, so that every press stroke 4 Reinforcements are made,
• - conveying the four preheated reinforcements by means of a gantry robot ( 13 ) of two injection machines ( 14 ), holding them with his claws and arranging them in the molds,
• Automatic loading of melaminated paper or transparent decorated film by means of individual robots,
• Overmolding for coating the reinforcements,
• Unloading the injection machines and removing the reinforced plates by means of the same loading robot ( 15 ), which supplies it to another injector for overmolding the frame, wherein the lid is formed.

In an improved embodiment, which in the 3 and 4 is shown, the structure is formed from a single piece, which the plate ( 5 ' ) and the frame ( 7 ' formed with recycled material and completely coated with a heat-formed transparent film ( 6 ' ) which is decorated on its inner side for attachment to the single, plate and frame forming piece. The other components of the lid are provided with the same reference numerals as those of the first embodiment of the 1 and 2 because there are no changes in any of their properties.

Concerning the manufacturing method of the reinforced lid according to the embodiment of the 3 and 4 , this varies in that the last injection operation described in the first embodiment is omitted and that it is used for overmolding the frame, since the unit of plate and frame is initially formed as a single piece, so that the lid unit the injection machines, which are used for overmolding the metal reinforcements leaves in a finished state.

In another embodiment, which in the 5 and 6 is shown, the structure is also formed from a single piece which the plate ( 5 ' ) and the frame ( 7 ' ) is formed of a new material, wherein the part of the single piece, which of the plate ( 5 ' ), with melamine paper ( 6 ) and fixed with heat-activated adhesive to the upper side of the lid plane. The other components of the lid are given the same reference numerals as those of the previous embodiment, since there is no change in any of their properties.

Regarding the manufacturing method of the reinforced lid according to the embodiment of the 5 and 6 This varies in that the last injection operation which was described in the first embodiment and served to overmold the frame is eliminated since the plate and frame were initially formed as a single piece, so that the lid unit can inject the injection machines the metal reinforcement used to leave in a finished state.

In another embodiment, which in the 7 and 8th is represented by the unit between the plate ( 5 '' ) and the frame ( 7 '' ) modified compilation such that instead of enclosing the plate ( 5 '' ) at its edges the frame ( 7 '' ) is placed on this in the region of its upper diameter, while both parts by a along the lower or inner side of the plate ( 5 '' ) running bed of adhesive, the plate ( 5 '' ) is clad with melaminated paper affixed to the upper surface of the lid plane with heat-activated adhesive.

The other components of the lid have the same reference numerals as those of the first embodiment of the 1 and 2 because there is no change in any of their properties.

In a final embodiment, which by the 9 and 10 1, the structure is based on the separation of the low-performance (recycled) plastic plate from the over-molded frame made of virgin material, which in the first embodiment of FIG 1 and 2 with the arrangement of the unit of plate ( 5 ''' ) and frames ( 7 ''' ) is modified such that instead of embracing the edges of the plate ( 5 ''' ) the latter is placed on them in their region of the upper diameter, both parts together by an ultrasonic welding bed ( 17 ), which are along the upper or outer surface of the plate between their edges and the inner surface of the attached part of the frame ( 7 ''' ), with the panel of melaminated paper ( 6 ), which is fixed with a heat-activated adhesive to the upper surface of the lid plane.

The other components of the lid retain the same reference numbers as those of the first embodiment of the invention 1 and 2 because there is no change in their properties.

Claims (8)

Reinforced cover for household electrical appliances, characterized in that its reinforcement consists of thin strips ( 1 ) made of steel, which are mounted on planes which are perpendicular to the interior of the cover, parallel to each other and to the hinge axis of the cover and at a uniform distance, which via a rectangular support strip ( 2 ) at the end to which they are attached to the inner level of the lid while the aforesaid tapes ( 1 ) with a plastic coating ( 3 ) are overmolded and protected against lateral deformation (tipping over) by means of clamps along both sides thereof. A reinforced lid for household electrical appliances according to claim 1, characterized in that its structure comprises: a plate with low mechanical performance ( 5 or 5 ' or 5 '' or 5 ''' formed by the molding process, the upper or the outer side of which is covered by a melamine sheet ( 6 or 6 ' coated with heat-active adhesive or with a transparent film decorated on the inside, fastened during the molding process, the above-mentioned plate being provided with metal moldings ( 1 ) and the arrangement with a high-performance plastic frame ( 7 or 7 ' or 7 '' or 7 ''' ), which encloses them at their edges. Reinforced cover for household electrical appliances according to claims 1 and 2, characterized in that the structure of the cover is formed from a single piece, the plate ( 5 ' ) and the frame ( 7 ' ), is made of recycled material and is completely covered with thermoformed transparent film ( 6 ' ), decorated on the inside for mounting on the single part representing the plate and frame. Reinforced cover for household electrical appliances according to claims 1 and 2, characterized in that the structure of the lid consists of a single structure of the plate ( 5 ' ) and the frame ( 7 ' ), poured from virgin material, while the part which is at the single part of the plate ( 5 ' ), with paper provided with melamine ( 6 ) coated with heat-active adhesive on top of the cover plate. Reinforced cover for household electrical appliances according to claims 1 and 2, characterized in that the plate ( 5 '' ) and the frame ( 7 '' ) are connected to each other in such a way that they form an arrangement in which the frame ( 7 '' ) not the edges of the plate ( 5 '' ), but is placed on the outer peripheral region, while both parts by a border of adhesive ( 16 ) along the lower or inner side of the plate ( 5 '' ) between its edges and the inside of the frame walls ( 7 '' ), the aforesaid plate being provided with melamine-coated paper ( 6 ), which is fixed with heat-active adhesive on top of the cover plate. Reinforced cover for household electrical appliances according to claims 1 and 2, characterized in that the plate ( 5 ''' ) and the frame ( 7 ''' ) are connected to each other in such a way that they form an arrangement in which the frame ( 7 ''' ) not the edges of the plate ( 5 ''' ) but is placed on the outer peripheral region, while both parts by an ultrasonic welding strip ( 17 ) along the lower or inner side of the plate ( 5 ''' ) between its edges and the inside of the frame walls ( 7 ), the aforementioned plate ( 5 ''' ) with melamine paper ( 6 ), which is fixed with heat-active adhesive on top of the cover plate. Process for the production of reinforced covers for household electrical appliances of the technical characteristics described in the preceding claims, characterized in that it comprises the following successive operations: unwinding ( 8th ) of the steel strip rolls with simultaneous use of four rolls, simultaneous alignment of the four strips in a compactor ( 9 ) with adjustable position; Profiling the ribbons in two initial and final passes ( 10 ) for the continuous shaping of the lid reinforcements; Preheating the four shaped strip strands in an induction unit ( 11 ) to prevent an excessive temperature differential during injection, which would lead to cooling and abrupt curing of the injected plastic upon contact with the metal and would prevent the relative displacement between both materials necessary during the injection process of the reinforcing layer: simultaneous cutting ( 12 ) of the four formed strip rods to the required mass, so that four reinforcements are produced at each stroke of the press; Displacement of the four preheated reinforcements by means of a lifting robot ( 13 ) of two injection machines ( 14 ) and this with his gripper tongs holds and puts in the forms; automatic loading of melamine coated paper or decorated transparent film to the injection machine by means of individual robots ( 15 ); Overmolding for the reinforcing layer; Unloading the injection machines and the reinforced plates by the same loading robot ( 15 ), which transports them to another injection machine for overmolding the frame, so that the lid is hereby formed. Process for producing reinforced lids for electrical Domestic appliances, all the work processes of the preamble of the preceding claim, thereby characterized in that the last injection machine for the over-molding the frame is omitted, leaving the lid completely finished is when he leaves the injection machine responsible for over-coating the coating the metal reinforcement is used.