The present invention relates to a metering device for dispensing shaped cleaning-agent bodies into a washing chamber of a household dishwasher.
In commercially available household dishwashers, it is necessary to add cleaning agent manually in powder form or in the form of tablets before the start of a washing process. It is usual for merely the rinse aid to be stored in liquid form in a reservoir inside the household dishwasher for multiple applications and to be added automatically via a metering device. The manual addition of cleaning agent before each washing process is regarded by many users as tiresome and inconvenient. As a result, attempts have been made for some time to develop so-called automatic metering systems for household dishwashers, which are designed to permit cleaning agent also to be stored in reservoirs for multiple applications and to be added automatically via corresponding metering devices.
For example, a metering device for dispensing cleaning tablets from a reservoir into the usable space of a dishwasher is disclosed in EP 1 159 913 A1, in which a substantially vapor-tight lock is arranged between the reservoir and the usable space. The reservoir in this case is configured for holding a loose filling of tablets and the lock has a transport device, for example in the form of a cell wheel, for actively transporting the tablets through said lock. The supply of tablets from the reservoir to the transport device is able to take place exclusively by gravity. However, a conveying apparatus which actively conveys the tablets (under the action of external force) from the reservoir to the transport device is preferred.
The extremely limited constructional space available in household dishwashers always constitutes a specific requirement in the development of automatic metering systems.
The object of the invention is to provide a compact metering device for dispensing shaped cleaning-agent bodies from a reservoir into a washing chamber of a household dishwasher, which permits a reliable automatic dispensing of shaped cleaning-agent bodies for a plurality of successive washing processes.
This object is achieved according to the invention by a metering device having the features as claimed in claim 1.
Accordingly, the metering device comprises a reservoir which is designed to hold a filling of the shaped cleaning-agent bodies and has a transfer opening in a region of the bottom of the reservoir. The metering device also comprises a transport device for actively transporting the shaped cleaning-agent bodies from the transfer opening of the reservoir into the washing chamber of the household dishwasher. According to the invention, a lifting device is provided, said lifting device being configured and designed for raising the bottom of the reservoir at least in parts, wherein a discharge slant toward the transfer opening is produced at least in parts or the downgrade of an existing discharge slant is increased at least in parts by the raising of the bottom.
The term “shaped cleaning-agent bodies” is intended to be understood within the scope of the invention as all shaped bodies with a defined external shape, which contain any constituents which are able to be used within the context of cleaning crockery. For example, tablets, pellets, granules or capsules fall within this term. The term is also not limited to shaped bodies which contain the actual cleaning agent. Rather, shaped bodies which comprise additives for use in rinsing cycles, for water-softening or water-conditioning and the like, are also intended to be encompassed thereby.
The reservoir is that region of the metering device which contains the store of shaped cleaning-agent bodies. The reservoir is designed to be refillable or even to be replaceable, for example in the form of a cartridge. The reservoir is designed to hold a filling, in particular a loose filling of shaped cleaning-agent bodies. This means that the shaped cleaning-agent bodies are randomly oriented in the reservoir and are not stored in a predetermined geometric arrangement.
The embodiment of the reservoir according to the invention to hold a filling of shaped cleaning-agent bodies permits simple and compact storage, even of larger quantities of shaped cleaning-agent bodies. Complex storage of the tablets is not required.
The wall portion on which the shaped cleaning-agent bodies are located due to gravity in the operating position of the reservoir is to be regarded as the bottom of the reservoir. The transfer opening arranged in the region of the bottom of the reservoir permits the supply of shaped cleaning-agent bodies to the transfer opening to be carried out exclusively by gravity or at least to be assisted by gravity. The “operating position” of the reservoir and thus also of the metering device is understood to mean the position in which the cleaning agent is metered when the household dishwasher is used correctly.
The transport device is preferably configured for carrying out discrete transport processes, wherein a predetermined quantity of cleaning agent in the form of shaped cleaning-agent bodies is transported in each transport process. The transport device may comprise, for example, a rotatably mounted cell wheel, at least one transport chamber being arranged on the periphery thereof.
The active transport of the shaped cleaning-agent bodies from the transfer opening of the reservoir into the washing chamber results in a desired quantity of cleaning agent being metered in a reliable manner. “Active transport” in this case means that the shaped cleaning-agent bodies are transported by the action of an external force. For example, a cell wheel may be actively rotated by means of a drive unit, for example an electric motor.
The lifting device according to the invention enables the bottom of the reservoir to be raised at least in parts and namely such that a discharge slant toward the transfer opening is produced at least in parts or the downgrade (the negative incline) of an already existing discharge slant is increased at least in parts by the raising process. In this manner, when the reservoir is filled to a maximum extent (when first using a new, filled reservoir or immediately after a refilling process) it is possible to align the bottom initially such that a constructional space available inside the household dishwasher is utilized as optimally as possible. As a result, it is achieved that as many shaped cleaning-agent bodies as possible may be held and, as a result, as many washing processes as possible may be carried out without refilling or replacing the reservoir. However, if the shaped cleaning-agent bodies are supplied to the transfer opening by gravity, or at least assisted by gravity, when the filling level of the reservoir reduces it may result in the shaped cleaning-agent bodies no longer being supplied in a reliable manner, since gravity is no longer sufficient and/or is incorrectly oriented. This problem is now remedied by a discharge slant toward the transfer opening being produced at least in parts or the downgrade of an already existing discharge slant being increased at least in parts by the raising process. In this manner, the supply of shaped cleaning-agent bodies by gravity, or assisted by gravity, is facilitated such that a reliable supply is ensured even when the filling level reduces.
In order to achieve a high level of user-friendliness for the customer it is advantageous if the lifting device is embodied and designed such that the bottom of the reservoir is raised automatically, i.e. without manual intervention, at least in parts when the quantity of shaped cleaning-agent bodies reduces in the reservoir. If the lifting device is provided with at least one spring means, for example in the form of a spiral spring and/or helical spring, the effect of the automatic raising may be achieved cost-effectively and by simple structural means.
As an alternative and/or additionally to the use of spiral or helical springs, the spring means may also be formed by an elastic strip. It is particularly advantageous if the bottom of the reservoir is formed at least in a partial region by the elastic strip itself.
In order to reduce the structural and financial cost as far as possible, it is expedient to effect the raising of the bottom at least partially, preferably exclusively, by the reducing weight of the shaped cleaning-agent bodies. This may be achieved, for example, by the weight force produced by the shaped cleaning-agent bodies counteracting the spring force of the at least one spring means. In this case, the at least one spring means is designed such that the spring force is sufficiently great that the bottom is in its non-raised initial position when the fully filled position is present and is successively raised when the filling level reduces and thus also the weight reduces.
A further embodiment of the invention provides that the bottom of the reservoir is formed by at least one portion of an articulated wall. In this case, it is advantageous to provide a guide on a wall of the reservoir adjacent to the bottom, said guide being able to serve at the same time as a seal for the adjacent wall. Depending on the type of shaped cleaning-agent bodies used, such a seal may be advantageous or even necessary.
According to a further embodiment of the metering device, a further guide means corresponding to the guide means is provided on the bottom, wherein the guide means and the further guide means cooperate such that, when raised, the bottom is exclusively movable along a path predetermined by the guide means.
In this embodiment, it is advantageously ensured that the jamming and/or twisting of the bottom in the reservoir is excluded.
According to a further embodiment of the metering device, the guide means has a rectangular external shape and the further guide means has a rectangular internal shape corresponding to the guide means, wherein the further guide means fully encompasses the guide means or is encompassed by three sides and is at least partially encompassed by the fourth side.
Advantageously, the guide means and the further guide means are adapted to one another such that a surface contact is present on the corresponding sides of the guide means and/or the further guide means. It could also be said that the corresponding sides of the guide means and/or of the further guide means fit snugly against one another. This may be ensured, for example, by the guide means being configured with an external periphery of (5×10) mm2 and the further guide means being configured with an internal periphery of (5.05×10.1) mm2. Thus it is ensured that a mechanical clearance between the guide means and the further guide means at the same time permits simple assembly and effectively prevents an undesired movement of the guide means relative to the further guide means and thus of the bottom in the reservoir.
According to a further embodiment of the metering device, a latching connection with a plurality of latching means is provided on a wall adjacent to the bottom and/or on the guide means, and a latch is provided on the further guide means and/or on the bottom, wherein the latch and the latching means of the latched connection cooperate such that a locking direction along the guide means and a release direction along the guide means limit the raising of the bottom.
This embodiment advantageously prevents the bottom from slipping back when the bottom has been raised by a specific distance. Thus an inclination of the bottom once reached will even be maintained when, for example, the spring is too weak in order to bear the weight of the shaped cleaning-agent bodies.
Advantageously, therefore, even a weaker spring may be used, for example, which may save costs. The latching connection and the latch thus cooperate, in particular, in the manner of a linear freewheel.
According to a further embodiment of the metering device, the latch is configured as an elastic element, wherein an elastic deformation of the elastic element permits a movement of the bottom in the release direction.
The elastic element is configured, for example, as a leaf spring. The elastic element is, in particular, produced from a plastics material or from metal. The elastic element is, for example, deformed in an elastic manner when, during a movement of the bottom, it strikes a latching means in the release direction. As soon as the latching means is overcome, the elastic element automatically returns into its initial position. Due to the shape of the latching means and also of the elastic element, an asymmetry which deploys a self-locking action is produced.
Advantageously, the elastic element may be configured, for example, integrally from a portion of the further guide means, for example on a lower end of the further guide means.
According to a further embodiment of the metering device, a spacing is provided between the latching means, so that upward and downward movements of the bottom are possible up to an amplitude of the length of the spacing.
This embodiment permits minor movements of the bottom, such as for example shaking. Such small movements promote a rearrangement of the shaped cleaning-agent bodies in the reservoir. This corresponds to a loosening effect which counteracts the jamming or blocking of the shaped cleaning-agent bodies. A reliable function of the metering device may be enhanced thereby.
According to a further embodiment of the metering device, the guide means and/or the further guide means cover the latching connection.
By means of this embodiment it is advantageously ensured that the shaped cleaning-agent bodies are not jammed between a latching means and the bottom, which would block a further raising of the bottom.
If a household dishwasher is provided with a metering device according to the invention, this metering device may be arranged, for example, on a door of the household dishwasher. According to one embodiment of the invention, in this case it is provided that the spring means are embodied and designed such that the bottom of the reservoir is only raised when the door is open and accordingly without being loaded by the weight of the shaped cleaning-agent bodies. The advantage of this design is that the shaped cleaning-agent bodies inside the reservoir are subjected to a significantly lower pressing force so that there is an even greater likelihood that agglutination or compaction is excluded. If required, by opening and/or closing the door a mechanical assistance of the raising process of the bottom of the reservoir may also be effected.
A further embodiment of the invention provides that the bottom of the reservoir has at least one recess which connects the reservoir to a cavity below the bottom, wherein the recess is configured such that the shaped cleaning-agent bodies are prevented from falling through the recess. Such a recess is capable, in particular, of permitting fine cleaning-agent particles, which are produced for example by mechanical abrasion of the shaped cleaning-agent bodies, to fall through the recess into the cavity below the bottom in the reservoir but is capable of holding back the shaped cleaning-agent bodies. Thus it may be easily prevented that such particles block the transport device or lead to other problems. The recess forms, in particular, a connection of the reservoir to the cavity below the bottom of the reservoir, which is formed by the bottom being raised by the lifting device.
If the shaped cleaning-agent bodies rub against one another, for example when slipping down, if a few of the shaped cleaning-agent bodies have been conveyed into the washing chamber, abraded matter from the cleaning agent may accumulate. The abraded matter comprises, for example, small particles of dust having a small particle size, i.e. in the range of micrometers up to a few millimeters in diameter. The recess is dimensioned so that these particles are able to fall through. At the same time, however, the recess is sufficiently small for the shaped cleaning-agent bodies not to be able to fall through.
The size ratio of the shaped cleaning-agent bodies to the recess may also be described as follows. A sphere may be defined for each body, such that the sphere is the largest sphere which is located entirely within the respective body. In the case of regular polyhedrons, for example, this sphere is denoted as an inner sphere. Accordingly, a circle of maximum size may be defined for any surface, said circle being located entirely inside the surface and also being able to be called an inner circle. The requirement of not falling through is at least always fulfilled when the diameter of the inner sphere of the shaped cleaning-agent bodies is larger than the diameter of the inner circle of the recess. For example, the diameter of the inner circle of an elongated rectangular gap is the same as the width of the gap when the width describes the shorter side of the rectangle. For a cylindrical-shaped cleaning-agent body the diameter of the inner sphere is provided by the smaller characteristic length of the cylinder. The characteristic lengths of the cylinder are the height of the cylinder and the diameter of the cylinder.
In particular cases, however, this condition may also be exceeded, i.e. the inner circle diameter of the recess is then greater than the inner sphere diameter of the shaped cleaning-agent bodies. This depends on the respective shape of the shaped cleaning bodies and the recess. If, for example, the shaped cleaning-agent bodies are cylindrical, wherein the height is smaller than the diameter of the cylinder and the recess is circular, then such a shaped cleaning-agent body may not fall through the recess as long as the diameter of the recess is smaller than the diameter of the cylinder.
In a further embodiment, the recess is configured as a gap arranged between the bottom and an adjacent wall. In this case, in particular, the width of the gap is limited such that the shaped cleaning-agent bodies are held back. Moreover, in particular, separators may also be provided, for example pins or spacers, which ensure that this spacing is maintained. Advantageously, the separators may be used at the same time as guide means for the bottom and/or as protection against the bottom slipping back. In further embodiments, a number of recesses, such as holes or slots, is provided in the surface of the bottom. In this case, in order to achieve the desired effect the geometric design of the recess is irrelevant.
Further advantageous embodiments and features of the invention form the subject-matter of the subclaims and the exemplary embodiments of the invention described hereinafter. The invention is described in more detail hereinafter by means of preferred embodiments with reference to the accompanying drawings.
In the drawings:
Elements which are the same or functionally the same are provided in the figures with the same reference numerals provided nothing further is specified.
The door 3 is shown in
The dishwasher 1 further comprises at least one washing item receptacle 12 to 14. In particular, a plurality of washing item receptacles 12 to 14 may be provided, wherein said washing item receptacles may comprise a lower basket 12, an upper basket 13 and/or a cutlery drawer 14. The plurality of washing item receptacles 12 to 14 are preferably arranged one above the other in the dishwasher cavity 2. Each washing item receptacle 12 to 14 is optionally displaceable into the dishwasher cavity 2 or out of said dishwasher cavity. In particular, each washing item receptacle 12 to 14 is able to be pushed into the receiving region 2 in an insertion direction E and is able to be pulled out of the dishwasher cavity 2 counter to the insertion direction E in an extension direction A.
The dishwasher 1 further comprises a metering device 100. The metering device 100 in the example of
Departing from the view in
In the region of the bottom 103 of the reservoir 101 a transfer opening 107 is provided and in the direction of gravity G a cavity 108 adjoins the transfer opening 107, a transport device 109′ in the form of a rotatably mounted cell wheel 109 being arranged in said cavity. The cell wheel 109 has a drive cylinder 110 which is actively driven by a drive unit, not shown, for example in the form of an electric motor. The cell wheel 109 also comprises a plurality of transport chambers 111 which in each case are configured for receiving a predetermined quantity of shaped cleaning-agent bodies 102. Here, the transport chambers 111 are separated from one another in each case by partitions 112 protruding radially from the drive cylinder 110. The partitions 112 are fastened to the drive cylinder 110, preferably integrally configured therewith.
On the one hand, the reservoir 101 with its transfer opening 107 and, on the other hand, an ejection channel 113 discharge into the periphery of the cell wheel 109.
During the operation of the metering device 100, shaped cleaning-agent bodies 102 located in the reservoir 101 are initially moved by gravity in the direction of the transfer opening 107 and in this manner are supplied to the cell wheel 109. During the rotational movement of the cell wheel 109, in each case a quantity of shaped cleaning-agent bodies 102 defined by the receiving volume of the transport chambers 111 falls out of the reservoir 101 through the transfer opening 107 into an empty transport chamber 111.
The shaped cleaning-agent bodies 102 are ejected through the ejection channel 113 which is located diametrically on the opposite side of the periphery of the cavity 108, and fall from there into the washing chamber 4 of the household dishwasher 1.
In the exemplary embodiment shown, the bottom 103 of the reservoir 101 was horizontally aligned in its initial position (when completely filled), so that the discharge slant was only produced by raising the bottom 103 by means of the lifting device 114. Naturally from the start, i.e. when the reservoir 101 is fully loaded, the bottom 103 may form a discharge slant. In this case, only the downgrade (negative incline) of the discharge slant in the direction of the transfer opening 107 is increased by the raising procedure. At this point a graphical representation of such an embodiment is dispensed with, since it would differ from the embodiment shown in
A further embodiment of a metering device according to the invention is shown in
As an alternative to this embodiment, for example, the guide means 121 may also be attached to the top wall 106 of the reservoir 101 (see
The latching connection 123 and the latch 125 shown in
A condition which is sufficient for the shaped cleaning-agent body 102 not to fit through the recess 126 is that the diameter D of the inner circle I of the shaped cleaning-agent body 102 (
Although the present invention has been described with reference to exemplary embodiments, the invention is able to be modified in many different ways. Reference characters used:
Number | Date | Country | Kind |
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10 2016 210 399.7 | Jun 2016 | DE | national |
10 2017 203 783.0 | Mar 2017 | DE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2017/060772 | 5/5/2017 | WO | 00 |