The invention relates to a household appliance, having a lye container, which at least in part is embodied in plastic, and having at least one ballast weight with at least one plastic body, which is attached to the lye container, where the mechanical connection of the plastic body of the ballast weight to a plastic area of the lye container is created by means of a plastic welding process.
Besides the attachment of ballast weights by means of friction and/or form fit using screws or a tension band, fixing by means of a plastic welding process is also known. DE 693 07 668 T2 thus discloses a washing machine or a combined washer/dryer, in which at least one ballast weight is attached to a lye container made of plastic. The ballast weight has a hollow plastic container which can be filled with water as the ballast material. The plastic container has a plastic outrigger element, which fits together precisely and thus in a form-fit manner with a corresponding plastic outrigger element on the lye container. The plastic container is arranged on the lye container in such a way that the two plastic outrigger elements are connected in a form-fit manner, where the pairs of matching outrigger elements are permanently connected to each other after joining by plastic welding of the plastic material. In addition to this DE 693 07 668 T2 also mentions the prior art whereby concrete blocks completely surrounded by a plastic covering are employed as ballast weights. Connection of this plastic covering to a lye container by means of a plastic welding process is also known from this. The fixing of the ballast weights to a lye container in the case of known household appliances requires a relatively high degree of effort. In all cases a form fit between the elements must first be established.
The object of the present invention is thus to create a household appliance of the kind specified at the outset, in which a connection between a ballast weight and a lye container can be embodied with little effort and a high degree of security. This object is achieved by a household appliance having the features as characterized in claim 1.
In a household appliance according to the invention, at least one raised connecting element is embodied on the plastic body of the ballast weight and/or on the plastic area of the lye container, which can come into contact with a contact surface of the plastic area or the plastic body to be connected, where the raised connecting elements can be connected in a bonded manner with the contact surface by means of a plastic welding process.
The household appliance comprises at least one ballast weight, where the ballast weight has at least one plastic body. The ballast weight is attached to the lye container, where the mechanical connection between the plastic body of the ballast weight and a plastic area of the lye container is effected by means of a plastic welding process.
In the case of a dishwasher as the household appliance, instead of being attached to a lye container the ballast weight can also be attached to a plastic housing section in the same manner. An essential idea of the invention is specifically that at least one raised connecting element is embodied on the plastic body of the ballast weight or the plastic area, to which the ballast weight is to be attached, which is brought into contact with the contact surface of the plastic area to be connected, and the raised connecting element can subsequently be connected in a bonded manner to the contact surface by means of the plastic welding process, in order to create the mechanical connection between the plastic areas.
The mechanical connection between the ballast weight and the lye container can thus be embodied with little effort, but nonetheless in a secure manner. Prior form fit joining of the ballast weight to the lye container is no longer required. The raised connecting element here extends in the direction of the contact surface of the plastic area with which the connecting element is to be connected in a bonded manner, thus enabling simple execution of the connection by means of a plastic welding process.
Advantageous embodiments of the invention are indicated in the subclaims, and can be combined individually or in any combination with each other or with the invention according to claim 1.
In an advantageous manner the ballast weight is embodied by at least two solids, with one material being the plastic body, and at least one further part of the body made of a solid material being connected with the plastic body. The second solid is preferably concrete or a concrete compound. An appropriate heavy ballast weight can thus be created which is especially suitable as a counterweight. The second solid can, however, also be gray cast iron or cast steel.
Such ballast weights attached to a lye container serve, in the case of a washing machine, to counterbalance this lye container, that is to increase its inertia and consequently to limit the oscillations generated in the lye container during a spin phase. This is then particularly advantageous if a drum of the washing machine is filled with items of laundry, and driven at a relatively high rotational speed. The aforementioned oscillations are brought about by conditions arising as a result of the uneven distribution of laundry items over the cylindrical wall of the drum.
In the case of a dishwasher, the ballast weight can, however, also be attached to a rear housing section embodied in plastic. Here, the ballast weight serves to offset at the rear the weight of the front-opening door of the dishwasher, so that the dishwasher does not tip forwards when the door is open.
Advantageously, the plastic body of the ballast weight extends in part into the second solid. In particular, provision can be made for the second material to be completely interspersed by the plastic body of the ballast weight. In this way dual-material ballast weights can be created, which can be embodied in a large number of different ways. In particular variable shapes of these two materials can here be implemented, which can be optimized with respect to the arrangement of the ballast weight on the lye container or on the housing section and in the household appliance.
Advantageously, the raised connecting elements are embodied in the manner of ribs. The connecting elements can, however, be embodied in any other shape which results in a raised structure of the connecting elements compared with the remainder of the plastic area. The connecting elements can, for example, be embodied in the form of pins, spikes or cones. Here too, an optimized shape can be selected depending on the situation and with respect to the requirements of the ballast weight (space requirements, strength, etc.).
Provision can be made for the plastic body of the ballast weight to be embodied in the form of a hook or a comb. On the one hand the connection of the plastic body to the second material of the ballast weight can thereby be improved and on the other the best possible mechanical connection with the plastic area of the lye container with respect to strength can be achieved.
Provision can be made for the connecting element or connecting elements to be embodied on the lye container, and for connection to the plastic body of the ballast weight to be contactable with an essentially uniform contact surface of the plastic body of the ballast weight. Equally, however, provision can also be made for the connecting elements to be embodied on the ballast weight, and to be contactable with an essentially uniform contact surface of the plastic area of the lye container.
Advantageously, a multiplicity of raised and preferably similarly oriented connecting elements is embodied on the plastic area or on the plastic body. It is also possible here to embody connecting elements on the contact surfaces of the parts to be connected with each other, and to weld these together. According to a further development of the invention, by means of multiplicity of connecting elements a number of contact areas can be created with the plastic area to be connected, by which the strength of the mechanical connection can be improved.
Provision can be made for the ballast weight to have at least two separate plastic bodies which are connected with a connecting stud. The connecting stud is preferably embodied in plastic. Provision can, however, also be made for the arrangement of a reinforced wire for the connection of at least two plastic bodies. The connection between at least two separate plastic bodies of the ballast weight can thereby be embodied in many different ways.
Provision can be made for the connecting stud and/or the reinforced wire to be surrounded, at least in part, by the second material of the ballast weight. This can, for example, be cast in the second material. A permanent connection between the materials can thereby be created, and a positionally stable arrangement at least of the connecting studs can be guaranteed.
The ballast weight can be embodied in cuboid or annular form. The form of the ballast weight is, however, not restricted thereby and can also be embodied in many other ways.
The connecting element is preferably integrated into the assigned plastic body. The plastic body and the connecting elements can thereby be manufactured in one piece. A single body can for example be manufactured here by means of injection molding.
The household appliance is advantageously embodied as a dishwasher, as a washing machine or as a combined washer/dryer.
The invention is described below in greater detail on the basis of exemplary embodiments shown in diagrammatic form. Where:
and
The section shown diagrammatically in
Besides the ballast weights shown here, such ballast weights could also be used, in which the plastic body takes the form of a plastic mass distributed in a concrete mixture. Amorphous and part-crystalline thermoplastic either with or without aggregates may, for example, be considered for this purpose. This can moreover also apply at least to the contact surface(s) of the lye container 1.
In the exemplary embodiments, the ballast weight 2 is embodied as two different parts made of solid materials. The ballast weight 2 here has a plastic body 21, which is embedded in a second body, the ballast body 22, which is made of concrete. Plastic body 21 and ballast body 22 are connected to each other in a form-fitted and force-fitted manner. In
According to
In addition the plastic body 21 has cross-sectionally longitudinal extensions 21d and 21e, which extend in the direction of the ballast body 22, and are completely surrounded by the concrete of the ballast body 22.
For connection of the ballast weights 2 to the front wall 11 of the lye container 1, the raised connecting elements 21a to 21c of the ballast weight 2 are arranged on the contact surface 11a. This gives rise to a mechanical contact between the contact surface 11a and these three connecting elements 21a to 21c. By means of a plastic welding process, for example vibration welding or mirror welding, a molten mass connection between the plastic body 21 of the ballast weight 2 and the front wall 11 of the lye container 1 is created. A bonded connection with the contact surface 11a is here established through melting of the raised connecting elements 21a to 21c. The raised connecting elements 21a to 21c here serve as the material supply for melt material, which after establishment of the connection becomes part of this connection.
According to the exemplary embodiments, the mechanical connection then established between the ballast weight 2 and the lye container 1 is created in such a way that in the event of heating, in particular of the plastics in the lye container 1 and the ballast weight 2, this connection cannot loosen. To this end, the contact surface 11a on the lye container 1 is matched to the corresponding connection surface of the plastic body 21 of the ballast weight 2, and in particular to the connection surfaces of the raised connecting elements 21a to 21c. The size of the connection surfaces between the plastic body 21, in particular its raised connecting elements 21a and 21c, and the contact surface 11a of the lye container 1, can be chosen according to the forces to be anticipated.
In addition, the form and force fit connection between the plastic body 21 and the concrete body 22 can withstand heat caused by the heating-up of the lye and any operating forces generated during the spinning of a drum of the washing machine.
Here the contact surface of the front wall 11 of the lye containers 1 has raised connecting elements 11b and 11c. The number of these has been selected solely by way of example, and can preferably vary upwards. The connecting elements 11b and 11c extend in one piece from the front wall 11. To prepare the connection, the contact surface 21f of the plastic body 21 of the ballast weights 2 is brought into contact with the raised connecting elements 11b and 11c. A plastic welding process is then used to create the bonded connection.
The sectional view in
In cross section, the ballast weights according to
The exemplary embodiment of a ballast weight 2 according to
As in
The ballast weight 2 according to
Each of these contact surfaces of the plastic body 21 can have at least one raised connecting element 21a (not shown). Provision can also be made, however, for at least one of these plastic bodies 21 to have a flat-faced area 21f (not shown) which can be connected in a bonded manner with at least one raised connecting element of the lye container.
Finally,
As a result of the various forms of embodiment of the ballast weight 2, a very wide variety of shapes can thus be created which are embodied from two solids. Besides low-cost concrete, only relatively simple plastic parts are required, which can be inserted into the mold during manufacture of the concrete parts. A simple embodiment of the entire ballast weight 2 can thereby be realized, even if the respective shapes of the concrete body 22 and the plastic body 21 are embodied in more complex form. Cost-effective realization of the ballast weight 2 can be guaranteed through the choice of material.
A rapid and secure connection can be created by means of the plastic welding process, whereby the welded connections can be produced fully automatically in a simple welding plant without further additives. The welded connections can be realizable for attaching a ballast weight to a front wall or to a mantle or to a base of the lye container. In addition the welded connections are suitable for oscillating systems with high spin speeds, because load forces are directed into the components concerned over a wide area, so that the tension in the mechanical connection is very small.
Number | Date | Country | Kind |
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10 2006 010 518.4 | Mar 2006 | DE | national |
10 2006 010 788.8 | Mar 2006 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2007/051582 | 2/20/2007 | WO | 00 | 9/3/2008 |