The invention relates to a domestic appliance having a detergent solution container and with at least one ballast weight which is mechanically connected via at least one of its own contact surfaces to at least one contact surface of the detergent solution container.
A wide variety of methods are known for attaching ballast weights using friction fits and force fits. Thus ballast weights are notoriously normally fastened by means of screws to the outer walls of detergent solution holders. Since these point-type fastenings have frequently not been satisfactory, the number of connections per ballast weight has increased steadily and yet these connections still take the form of points which, in conjunction with ballast weights made from the brittle material concrete, frequently leads to the formation of cracks between the connection points. In addition this increases the demands to strict tolerances by the plurality of fastening points to be matched in their dimensions to one another.
In a similar way connections between plastic detergent solution containers and ballast weights have been created by means of molded-on dowels in which by an injection process (for example through a additional screw screwed in along the extent of the dowel) additional support surfaces have been obtained. However even this form of fastening was unable to satisfy requirements, because the area between the fastening points are still at risk from bending stresses, which the brittle concrete material can often not withstand.
Furthermore clamp connections are also employed in which very powerful steel belt clamps take care of holding the ballast weights on the support surfaces of the detergent solution container of a washing machine. Here friction movements between the ballast weight and the support surfaces and wear to said surfaces are deliberately accepted, because the spring force of the clamps always adjusts the connection. A problem however—as with the dowel connection—is the tendency of the plastic of the detergent solution container to become viscous, so that the contact surfaces change their shape over and above the wear, which eventually however can lead to the connection coming apart.
Fastenings of ballast weights using a band clamp (DE 196 33 705 A1) have the disadvantage that the band clamp must fully enclose the ballast body. This requires a circular or ring-shaped ballast weight which greatly reduces the freedom of constructional design of detergent solution containers. Since the tensioning band must also enclose lug-type extensions on the detergent solution container, the design of a tool for detergent solution container is very expensive and the lug-type extensions must be shaped in a particular way in order to correspond to the appropriate indentations on the ballast weight.
Furthermore the fastening of ballast weights using a plastic welding method is known. DE 693 07 668 T2 thus discloses a washing machine or a combined washer/dryer in which at least one ballast weight is fastened to a detergent solution container made of plastic. The ballast weight features a hollow plastic container, which can be filled with water as ballast material. The plastic container of the ballast weight also has an outer contour which precisely matches and thus makes a form fit with a corresponding structure on the detergent solution container. The plastic container is arranged on the detergent solution container such that the two structures fit tightly into one another and the pairs of the matching structures are permanently connected to each other by welding once joined together. Over and above this, prior art is also known in 693 07 668 T2, in which concrete blocks which are completely enclosed in a plastic envelope are known as ballast weights. Such a plastic envelope is also connected to the detergent solution container by a plastic welding process. Plastic welding processes require complex machines in the production line which make it more expensive to manufacture the detergent solution containers connected to the ballast weights. Also this form of attachment is linked to the use of thermoplastic plastics on both parts—detergent solution container and ballast weight.
The object of the present invention is thus to create a domestic appliance of the type stated at the outset, in which a connection between a ballast weight and a detergent solution container can be embodied at low cost and safely.
This object is achieved in accordance with the identifier of claim 1 by the contact surface of the ballast weight and of the detergent solution container being glued to each other.
An inventive domestic appliance has a detergent solution container with at least one ballast weight that is mechanically connected via at least one of its own contact surfaces to at least one contact surface of the detergent solution container. Inventively the ballast weight is fastened to the detergent solution container by gluing the contact surface of the ballast weight to the contact surface of the detergent solution container, with the mechanical connection being embodied by a glued joint.
A major advantage of this connection method is the large-surface or full-surface adhesion between the contact surfaces, in which the stresses for the ballast weight can be widely distributed. This is especially of advantage when used in washing machines, because in such systems in the course of an agitation process, in which the oscillating system consisting of laundry drum and detergent solution container with a number of built-in components (motor, heating, bellows-type collar etc.) is excited into many thousands of vibrations which impose a strain on the attachment elements of the ballast weight.
The complete lack of raised areas, which would be used to connect the ballast weight such as by screws for example to the detergent solution container, also allows the manufacturer every possible freedom in the embodiment of the external form of the ballast weight.
Depending on the pairing of the two materials to be connected to one another, there are known measures to be taken in general adhesive technology for preparing the gluing. These can be washing the contact surface, treatments which increase adhesion, e.g. through a plasma treatment, of contact surfaces made of plastic, roughening or smoothing by brushing or sanding, application of primers or similar, that are easily able to be integrated into automated assembly processes.
Numerous variants described in the subclaims enable the invention to be advantageously further developed. These variants can be used in any possible combination individually or jointly with the gluing in accordance with claim 1.
In such cases the contact surface of the detergent solution container can advantageously be embodied at least in some areas from plastic or metal. In such cases it is useful for the ballast weight to also be able to be fastened to detergent solution containers made of stainless steel or plastic.
The ballast weight can be embodied from metal, preferably cast metal, from plastic or from pure concrete. Ballast weights made of metal can be used in particular if the space in the interior of the domestic appliance requires a ballast weight of low volume.
An advantageous embodiment of the invention features at least one raised area on the contact surface of the ballast weight or of the detergent solution container which is in contact with an essentially flat area of the contact surface to be connected, with adhesive being deposited in the hollows between the raised parts which extends into the flat area when the parts are glued together in order to prepare the adhesive connection between the contact surfaces. In such cases the raised areas can serve to keep a defined distance between the contact surfaces until the glued connection is hardened. The connection between the ballast weight and the detergent solution container can be made with little effort and yet still safely by using this method.
A prior form-fit fitting of the of the ballast weight onto the detergent solution container is not necessary, but can be desirable in order to make it easier to fix the ballast weight into its intended position. Raised areas preferably extend in the direction of the contact surface.
The embodiment of the ballast weight as a body made entirely of concrete will be preferred. However armoring within the concrete body can be provided to increase the stability.
In an advantageous manner however the ballast weight can be embodied from at least two solid materials, with one material being a plastic. At least one further section of the ballast weight consists of another solid material and is connected to the plastic part.
In a preferred manner the second solid material is concrete or a compound containing concrete. This allows a sufficiently heavy ballast weight to be created. Such a ballast weight fastened to the detergent solution container serves to make it heavier and increase the mass inertia and consequently to restrict the vibrations of the detergent solution container during an agitation phase. This is especially advantageous if a washing machine drum rotating in the detergent solution container is filled with an unbalanced load of washing and driven at a relatively high speed.
In an advantageous manner the plastic element of the ballast weight is a discrete plastic part which extends partly into the second solid material. In particular there can be provision for the second material to be completely penetrated by the plastic part of the ballast weight. A two-component ballast weight created in this way allows a diversity of embodiments. In particular in such cases these two components can be created in a variety of shapes which can be optimized in respect of the arrangement of the ballast weight on the detergent solution container and available space within the domestic appliance.
In an advantageous manner the raised areas are embodied in the form of ribs. However the connecting elements can be designed to assume any other shape which leads to a raised structure of the connection elements by comparison with the remaining part of the contact surface. Thus for example a pin-shaped of point-shaped or cone-shaped embodiment of the raised areas is advantageous. Here too in respect of the requirements of the ballast weight (space requirement, strength, etc.) a shape optimized for the situation concerned can be selected.
The plastic part of the ballast weight can feature an undercut. On the one hand this allows the connection of the plastic part to the second solid material of the ballast weight to be improved and on the other hand allows a best possible mechanically-rigid connection with the contact surface of the detergent solution container to be obtained.
The raised areas can advantageously be embodied on the detergent solution container and can be glued to the contact surface of the plastic part of the ballast weight. In another variant the raised areas can be embodied on the ballast weight and have adhesive contact with an essentially flat area of the plastic area of the detergent solution container.
In an advantageous manner a plurality of raised areas is embodied in the plastic area of the detergent solution container or on the plastic part of the ballast weight, extending essentially in the same direction. This plurality of connecting elements enables a number of contact areas with the plastic area to be connected to be created, enabling the strength of the mechanical connection to be improved. In addition the parts of the adhesive deposited between the raised areas guarantee the distribution of adhesive to all contact areas.
There can be provision for the plastic part of the ballast weight to have at least two separate contact surfaces, which are connected by a connection pin. Preferably the connection pin is embodied from plastic. A special form of strengthening is provided however by an armoring wire between the two contact surfaces.
There can be provision for the connecting pin and/or the armoring wire to be surrounded in at least some areas by the second material of the ballast weight. For example they can be encapsulated in the second material. This allows a firm connection to be created between the materials and a positionally-stable arrangement of the plastic part to be guaranteed.
The ballast weight can advantageously be embodied as a cube or as a part ring. However this does not exclude other shapes of ballast weight.
The raised areas are preferably an integral component of the assigned plastic part. This enables the plastic part to be manufactured in one piece with the raised areas. For example the plastic part for the ballast weight can be manufactured by a single injection molding process.
In an advantageous manner the domestic appliance is a washing machine or a combined washer/dryer.
The invention is explained in greater detail below with reference to a number of exemplary embodiments for the fastening of a ballast weight to a detergent solution container a washing machine. The figures show
In housing 1 of the washing machine shown in FIG. I a detergent solution holder 2 is supported to allow oscillation of spring-loaded legs 3. An electric motor 5 drives the laundry drum 6 supported horizontally within the detergent solution container 2 via a belt drive 4. The laundry drum 6 and the detergent solution container 2 have a common loading opening 9, through which washing 15 can be introduced into the drum 6 or removed from it and which is sealed by a bellows-type collar 7 from the inner chamber of the housing 1. The loading can be closed at the front by a door 8.
Since the motor 5 is accommodated at the bottom to the rear on the vibration detergent solution holder system, its large weight must be compensated for on the side lying opposite the center of gravity of the detergent solution holder system. The ballast weight 10 which is fastened to the front side of the detergent solution container 2 above the loading opening 9 is used for this purpose. The ballast weight 10 and the detergent solution container 2 are connected by gluing 133 between the touching contact surface 11 of the ballast weight 10 and 12 of the detergent solution container 2.
The ballast weight 10 is embodied in all exemplary embodiments from two different solid materials. The main component of the ballast weight 10 consists of concrete. The plastic part 13 is used to fasten the ballast weight 10 to the detergent solution container 2 and in the different examples depicted in
In the exemplary embodiment depicted in
A ballast weight 16 in accordance with
A similarity shape is provided for the plastic part 171 in
The contact surfaces 165 or 175 of the ballast weight 16 or 17 in accordance with
It is also possible, instead of the channels, to provide indentations with a large volume, with the adhesive mass not completely filling such recesses. Even after the ballast weight is completely pressed onto the detergent solution container complete filling of the recesses with the pressed adhesive mass is not absolutely necessary.
With suitable peripheral conditions (application technique, adhesive preparation, material selection and nature of the adhesive) it is also possible to dispense entirely with such channels and to provide a completely level surface 185 on ballast weight 18 (
The plastic part 201 of the ballast weight 20 in
A completely different construction, which still comes within the framework of the invention, is provided for the ballast weight 21 in
In
The gluing of the plastic part 901 anchored in the concrete body 903 is to be seen accordingly, in that two or more adhesive beads 127 are provided on the contact surface 12 of the detergent solution holder 2 and the ballast weight 90 is subsequently pressed with its contact surface 905 against the contact surface 12 of the detergent solution container 2.
To manufacture the adhesive connection—as merely indicated in FIGS. 8 and 9—a number of adhesive beads are laid onto one of the contact surfaces, e.g. the (12) of the detergent solution holder 2, and thereafter the ballast weight 89 or 90 is pressed onto the detergent solution holder until the adhesive has hardened sufficiently. The best positioning of the adhesive bead can be determined by trial and error and be executed automatically by machine in the series manufacturing process. In the example shown in
The size of the overall adhesive surface between the plastic part 161, 171, 181, 191, 201, 211, 801 or 901, especially the recesses 166 or 176 or 206 and the contact surface 12 of the detergent solution holder 2 can vary and be embodied as a function of the forces created by the loading, e.g. the forces created during agitation.
In the view of the surfaces to be glued shown in
The different embodiments of the ballast weight 10 thus allow a very wide diversity of shapes to be designed which are embodied from two solid materials. As well as cost-effective concrete only relatively simple plastic parts are needed which are to be inserted into the mold during the manufacturing of the concrete parts. This enables a simple embodiment of the overall ballast weight to be implemented, even if the shapes of the contact surfaces 11 on the ballast weight 10 or 12 on the detergent solution container 2 are complex in their embodiment. A cost-effective implementation of the ballast weight can also be guaranteed by the choice of material.
The gluing will resist correspondingly greater forces if the adhesive beads 127 are dimensioned longer, as shown in
In accordance with the different requirements which are produced by various peripheral conditions such as material pairing between ballast weight and adhesive as well as adhesive and detergent solution container for example or also the type and the size of the forces acting on the gluing, different forms can be employed when the adhesive bead(s) is/are applied.
The variants shown in
The adhesive mass, depending on the above-mentioned different requirements can also be applied in another form, for example adhesive can be applied in U-shaped beads. In addition a point-form or surface application of the adhesive mass is also conceivable.
The gluing process enables a fast and safe connection to be made with the glue connections easily able to be established by a simple automated system. The glued connection are able to be realized both for a ballast weight attachment to surfaces of a face or sleeve or a floor of the detergent solution container. In addition the glued connections are suitable for oscillating systems with a high agitation speed since the load can be introduced over a large surface into the respective component, so that the tension per surface element in the mechanical connection is very small. In this case the proposed measures can be applied in the same way to detergent solution containers made from stainless steel and for ballast weights made from pure concrete or from cast metal. In an advantageous manner the adhesive masses, preferably consisting of a polyurethane or of a silicon and the volumes of the adhesive masses dictated by the geometrical requirements compensate for the uneven thermal expansions of the different materials and also from frequent changes of load, during the agitation in a washing machine for example.
1 Domestic appliance
2 Detergent solution container
4 Belt drive
5 Electric motor
7 Bellows-type collar
9 Loading opening
10 Ballast weight
11 Contact surface of ballast weight 10
12 Contact surface of detergent solution container
13 Plastic part
15 Ballast weight
16 Ballast weight
17 Ballast weight
18 Ballast weight
19 Ballast weight
20 Ballast weight
21 Ballast weight
80 Ballast weight
90 Gluing surface
102 Gluing surface
103 Gluing surface
104 Gluing surface
117 Adhesive bead
127 Adhesive bead
128 Cone on contact surface 12
147 Adhesive bead
157 Adhesive bead
161 Plastic part of ballast weight 16
162 Extensions of plastic part 161
163 Concrete body of ballast weight 16
164 Limb of the plastic part 161
165 Contact surface of ballast weight 16
166 Channels (recesses) of plastic part 161
167 Adhesive bead
171 Plastic part of ballast weight 17
173 Concrete body of ballast weight 17
174 Limb of the plastic part 171
175 Contact surface of ballast weight 17
176 Channels (recesses) of plastic part 171
177 Adhesive bead
181 Plastic part of ballast weight 18
183 Concrete body of ballast weight 18
185 Contact surface of ballast weight 18
198 Adhesive bead
191 Plastic part of ballast weight 19
192 Extensions of plastic part 191
193 Concrete body of ballast weight 19
195 Contact surface of ballast weight 19
197 Adhesive bead
201 Plastic part of ballast weight 20
202 Rails of plastic part 201
203 Concrete body of ballast weight 20
204 Side rails of plastic part 201
205 Contact surface of ballast weight 20
206 Recess of plastic part 201
207 Adhesive bead
211 Plastic part of ballast weight 21
212 Retaining flanges of plastic part 211
213 Concrete body of ballast weight 21
215 Contact surface of ballast weight 21
217 Adhesive bead
801 Plastic part of ballast weight 80
803 Concrete body of ballast weight 80
805 Contact surface of ballast weight 80
808 Hollow cone of plastic part 801
901 Plastic part of ballast weight 90
903 Concrete body of ballast weight 90
905 Contact surface of ballast weight 90
Number | Date | Country | Kind |
---|---|---|---|
10 2006 011 734.4 | Mar 2006 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/EP2007/051578 | 2/19/2007 | WO | 00 | 1/21/2009 |