Abstract:
The invention relates to a distributing head, which is used to distribute a hot liquid over an infusion material in a beverage maker. The distributing head has a housing ( 1, 2, 3, 4 ), which has an interior ( 7 ) and an inlet ( 13 ) for the liquid that opens into the interior ( 7 ) and a plurality of outlet openings ( 35 ), which lead outward from the interior ( 7 ). The housing ( 1, 2, 3,   4 ) has at least one first portion ( 1, 2 ), which is made of a first material, and at least one second portion ( 3, 4 ), which is made of a second material that repels liquid better than the first material.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a distributing head for distributing a hot liquid over an infusion material in a beverage maker. Distributing heads of such a type are often used particularly in coffee makers in which the coffee powder held in a filter is doused with hot water during the preparation of the coffee. 
       PRIOR ART 
       [0002]    Coffee makers in which the coffee is prepared using ground coffee held in a filter and brewed with hot water have been known for a long time. The water for this purpose is heated in a known manner in a flow heater. From said flow heater, the water then rises up usually via a vertical pipe and reaches an upper, horizontal pipe. This horizontal pipe ends above the filter. From there, the hot water drips through one or more exit openings onto the coffee powder held in the filter. The water trickles through the coffee powder and in doing so releases the aroma substances from said coffee powder. The filter here serves to let the prepared coffee beverage pass through in the downward direction and to retain the depleted coffee powder. From the filter, the prepared coffee beverage finally drips into a container which is located below the filter and which is usually a cup or a coffee pot. 
         [0003]    The same principle is also often used for the preparation of other beverages, for example tea. 
         [0004]    Instead of coffee powder, a correspondingly different infusion material, so tea leaves in the case of tea, is then put into the filter. 
         [0005]    So that the aroma substances can be released from the infusion material as completely as possible by the hot water, it is aimed for in beverage makers of such a type that the water drips in as spatially uniform a manner as possible onto the infusion material held in the filter. For this purpose, distributing heads which fan out the water flow at the end of the horizontal pipe above the filter are known. By way of example, a distributing head of such a type is disclosed in document U.S. Pat. No. 4,354,427. The distributing head presented therein forms a distribution chamber for the inflowing water, from which distribution chamber the water drips down onto the coffee powder through a multiplicity of exit openings. A further such distributing head is described in U.S. Pat. No. 6,244,162. 
         [0006]    A problem with beverage makers of such a type is that dirt particles and deposits of minerals contained in the water, such as in particular lime, often accumulate along the inner faces of the pipes and lines. These deposits are particularly problematic in the region of the often narrow exit openings of the distributing head. The hot water in this region often has a comparatively slow flow rate, while at the same time it makes contact with many inner faces of the beverage maker. In addition, after use of the beverage maker, water residues often remain there, leading to further deposits being formed. Moreover, on account of their usually small diameter, the exit openings can be rapidly clogged by the dirt particles or closed by the deposits, which, in some circumstances, can considerably compromise the functionality of the beverage maker. 
         [0007]    In order to avoid deposits of such a type, U.S. Pat. No. 6,755,119 proposes to use a polyetherimide material having a deep surface porosity for the distributing head. However, this considerably limits the choice of materials for the distributing head. It is moreover proposed to design the exit openings as tubular structures which in each case extend upward from a surface which lies in between then. Distributing heads for beverage makers which can be taken apart in a simple manner for cleaning purposes are described in WO 03/092456 and IE 060105. However, the fundamental problem, namely the formation of deposits in the first place, is not solved thereby. 
       SUMMARY OF THE INVENTION 
       [0008]    It is thus an object of the present invention to specify a distributing head for a beverage maker in which deposits of dirt and lime are avoided, in particular in the region of the exit openings, or the formation of said deposits is at least slowed down. For achieving this object, a distributing head as specified in claim  1  is proposed. In addition, a beverage maker having a distributing head of such a type is proposed. Advantageous embodiments of the invention are specified in the dependent claims. 
         [0009]    All indications of locations and directions used in the following, such as top, bottom, horizontal, vertical, upward, downward, etc. are in each case to be understood in relation to the direction of gravity for a distributing head used as intended in a beverage maker. It is usually the case then that the distributing head is located with its exit openings directly above the infusion material. 
         [0010]    The present invention thus provides a distributing head for distributing a hot liquid over an infusion material in a beverage maker, having:
       a housing with an interior space, with an inlet which is intended for the liquid and leads into the interior space and with a multiplicity of exit openings which lead from the interior space to the outside.       
 
         [0012]    The housing here has at least one first portion which is made from a first material and at least one second portion which is made from a second material which, in comparison with the first material, is more liquid-repellent. 
         [0013]    A liquid-repellent material is to be understood to mean a material which is not readily wettable by a liquid. Water thus very easily runs off the surfaces of materials of such a type. The second material is more liquid-repellent than the first material in particular when the contact angle of the same liquid is greater on the second material than on the first material. Preferably, the contact angle of the liquid on the second material here is greater than 90°. The second material may then be described as being hydrophobic. 
         [0014]    The infusion material may be in particular coffee powder or tea leaves. The hot liquid used is usually water. The interior space of the housing usually serves to hold and guide the hot liquid, which, in said interior space, flows along a main flow direction from the inlet to the exit openings. The interior space of the distributing head here, excluding the inlet and exit openings, is preferably closable toward the outside in relation to the liquid, particularly preferably closable in a liquid-tight manner. 
         [0015]    The provision of a second portion which, in comparison with the first portion, is made from a material which is more liquid-repellent leads to the creation of deposits in the housing, at least in the region of the second portion, being avoided or at least considerably reduced. The second portion is thus particularly preferably in each case located on those spots of the distributing head which are particularly prone to deposits or where deposits have a particularly negative effect on the functioning of the distributing head. Preferably, the second portion is thus located in the form of a lining on the inner side, that is that side of the housing which faces toward the interior space. 
         [0016]    Preferably, the second material is designed to be softer than the first material. The second material typically has a Shore A hardness of 40 to 80, in particular 50 to 70. In contrast thereto, the first material has a preferred Shore A hardness of more than 80, particularly preferably of even more than 90. The second material is preferably a rubber-like material, particularly preferably silicone. 
         [0017]    The surfaces of the second portion may be polished, roughened or untreated. However, they are preferably polished, particularly preferably even polished to a high gloss. The hydrophobic properties of the surfaces can be improved in this manner. On account of this, the formation of deposits on the surfaces of the second portion is avoided or at least slowed down. Moreover, any lime deposits can be very easily wiped away, for example with a cloth. 
         [0018]    It is also the case that the surfaces of the second portion in particular can be treated, and have for example a correspondingly microstructured and/or nanostructured surface, so that they achieve a Lotus effect. 
         [0019]    Particularly preferably, the second portion is located at least in the region of the exit openings. The second portion is thus preferably located in that region which in each case extends between the different exit openings and immediately adjoins those. Moreover, the second portion is particularly preferably located in such a manner that it in each case forms the inner faces of the exit openings so that the liquid, when passing through the exit openings, makes contact exclusively with the second portion. Preferably, the exit openings are located within a perforated plate. At least one side of this perforated plate, which preferably represents part of the first portion, is coated preferably with the aforementioned second material, which particularly preferably extends into the holes of the perforated plate. 
         [0020]    The exit openings in each case preferably have an internal diameter of such a type that a droplet formation is facilitated when the liquid exits from the exit openings. In specific terms, an internal diameter of the exit openings of less than 4 mm, in particular of 1 to 3 mm, is preferred. In the event that the second material in each case reaches into the holes of a perforated plate of the first portion, the second material there in each case preferably has a radial thickness of 0.5 to 1 mm, in particular of 0.6 to 0.8 mm. The radial thickness here extends in each case in the plane of the internal diameter of the exit openings, that is to say perpendicularly to the inner surface of the exit openings. 
         [0021]    Preferably, the second portion is located in the entire region of the interior space. Particularly preferably, the second portion covers all surfaces of the first portion which face toward the interior space. Moreover preferably, all inner-side faces of further elements which delimit the interior space, such as for example closure elements, are likewise made from the second material. In other words, the second portion thus preferably forms all liquid-carrying surfaces of the distributing head. On account of this, deposits of dirt and lime can be avoided or reduced in the entire interior space. 
         [0022]    The first and the second portions of the housing in each case may be designed in one or more parts. In a particularly preferred embodiment, the second portion is moulded onto the first part. In this event, the first portion thus preferably forms a basic housing structure, which is advantageously overmoulded with the second material on the inner side, at least in the region of the exit openings. In contrast to this, however, embodiments are also conceivable in which the second portion forms the basic housing structure, which is supported and kept in shape by the first portion. 
         [0023]    Preferably adjoining the exit openings, the interior space forms a distribution chamber for distributing the liquid. The distribution chamber here may serve in particular to distribute the liquid over a comparatively large area. Moreover, the housing advantageously may have a perforated plate, within which the exit openings are located and from which preferably a substantially encircling side wall extends along a main axis. In this case, the distribution chamber is delimited by the perforated plate and the side wall. Based on a usually slow and non-laminar flow of water in the interior of the distribution chamber, the inner faces of the perforated plate and of the side wall, which face toward the distribution chamber, are normally particularly prone to deposits. The second portion is, therefore, preferably located in such a manner that it forms said inner faces in full in each case. The first portion of the housing is, therefore, preferably completely covered by the second material in the region of the distribution chamber. 
         [0024]    In the event that the interior space has a distribution chamber of such a type for distributing the liquid, the housing preferably has an inlet duct which, at a mouth opening, leads into the distribution chamber. The inlet duct here may define in particular the main flow direction of the liquid in the interior space. The inlet for the liquid into the inner space is advantageously formed in a region of the inlet duct which is located opposite to the mouth opening. This inlet is advantageously configured as a connector which particularly advantageously extends substantially in the same direction as the main axis of the side wall of the distribution chamber. The connector is preferably designed for connecting to a riser of the beverage maker. 
         [0025]    Advantageously, the inlet duct is located in an inclined manner in relation to a direction which is perpendicular to the main axis of the side wall of the distribution chamber. When the distributing head is inserted as intended into the beverage maker, the inlet duct is thus advantageously inclined toward the direction of the distribution chamber in a downward manner in relation to the direction of gravity. On account of this, the liquid runs downward in the direction of the distribution chamber and cannot remain in the inlet duct or even flow back to the inlet of the distributing head. 
         [0026]    The perforated plate preferably has a planar first surface, which faces toward the distribution chamber and which is formed by the first portion, and a planar second surface, which faces toward the distribution chamber and which is formed by the second portion. Here, the first and the second surfaces preferably extend in two directions which are inclined in relation to one another. Here the second portion, particularly in the region of the exit openings, may have a thickness which preferably continuously decreases as the distance from the mouth opening of the inlet duct increases. This decreasing thickness of the second portion may, in particular, serve so that the liquid, after entering into the distribution chamber, continues to flow within said distribution chamber on account of gravity and also reaches those exit openings which, in comparison with the other exit openings, are located furthest away from the mouth opening of the inlet duct. This avoids the situation where the largest part of the liquid flows only through the exit openings which are located closest to the mouth opening of the inlet duct. The liquid can thus be more uniformly distributed in the distribution chamber. 
         [0027]    The distributing head advantageously has one or more closure elements which are releasably attached on the housing in order to close said housing toward the outside. Access to the interior space, for example for cleaning purposes, is thus made possible. In the event that the interior space forms a distribution chamber, at least said interior chamber is advantageously accessible from the outside by means of a closure element which is releasable from the housing. 
         [0028]    The distributing head may have flow elements which are located in the region of the exit openings and project into the interior space in order to distribute the hot liquid. Such flow elements, which are preferably located in the distribution chamber if the distributing head has one, may in particular serve for routing the liquid in as uniform amounts as possible to the exit openings. This makes it possible to avoid the situation where, during use of the beverage maker, overall larger amounts of liquid flow through certain exit openings than through others, which would have the consequence that water is sprinkled in a non-uniform manner on the infusion material. Preferably, the flow elements in each case are formed exclusively by the second portion. Preferably, the flow elements are moreover located in a mirror-symmetrical manner, the plane of symmetry preferably extending along the main flow direction of the liquid in the interior space. The flow elements in each case may in particular have substantially the shape of a wedge, the tip of said wedge pointing in that direction from which the liquid flows toward the flow element according to the main flow direction in the respective region in each case. The wedge here is preferably formed from two legs which between them enclose an angle of preferably 45° to 90°, particularly preferably of approximately 70°. The two legs here may be designed to have different lengths in each case in their longitudinal direction, in particular when the flow element in each case is located at a distance from the aforementioned plane of symmetry. Preferably, the leg which in each case here is located closer to the plane of symmetry is designed to be shorter. The flow elements which are located directly on the plane of symmetry, however, in each case preferably have the shape of a wedge with two legs of equal length. Preferably, the flow elements in each case extend over the entire height of the interior space. 
         [0029]    The first portion of the housing may be designed in particular in one piece. However, for example in order to facilitate attachment of the second portion during manufacturing, when said second portion is designed as a lining, said first portion may have a main part and also a cover which is attachable on the main part. After manufacturing, the main part and the cover can then be connected to one another in a permanent manner, for example by means of ultrasonic welding. The cover here may form, for example, an upper part of the inlet duct. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]    Preferred embodiments of the invention are described in the following by means of the drawings, which serve merely for explanatory purposes and are not be interpreted as being limiting. In the drawings: 
           [0031]      FIG. 1  shows a perspective view of a distributing head according to one embodiment of the invention; 
           [0032]      FIG. 2  shows a central sectional view of the distributing head of  FIG. 1  along the line II-II; 
           [0033]      FIG. 3  shows a perspective exploded view of the distributing head of  FIG. 1 ; 
           [0034]      FIG. 4  shows a perspective view of the main housing part of the distributing head of  FIG. 1 ; 
           [0035]      FIG. 5  shows a plan view onto the main housing part of the distributing head of  FIG. 1 ; 
           [0036]      FIG. 6  shows a perspective view of the main housing part of the distributing head of  FIG. 1  without a silicone lining; 
           [0037]      FIG. 7  shows a perspective view of the closure cover of the distributing head of  FIG. 1 ; 
           [0038]      FIG. 8  shows a perspective view of the housing cover of the distributing head of  FIG. 1 ; and 
           [0039]      FIG. 9  shows a perspective view of the closure plug of the distributing head of  FIG. 1 . 
       
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0040]      FIGS. 1 to 9  show various illustrations of a preferred embodiment of a distributing head according to the invention. The distributing head serves to distribute a hot liquid over an infusion material in a beverage maker. In such a beverage container, the infusion material, which may be, for example, coffee powder or tea leaves, is held in a filter and is doused with hot water from above via the distributing head. The prepared coffee beverage flows through the filter, which usually tapers from top to bottom, and from there drips into a cup or a coffee pot located below the filter. The depleted coffee powder here is retained by the filter. The distributing head here particularly serves to sprinkle the hot water in as spatially uniform a manner as possible over the infusion material, such that the aroma substances can be released from the infusion material by the water in an optimal manner. 
         [0041]    As shown in  FIG. 1 , in the present embodiment the distributing head has a housing  1 ,  2 ,  3 ,  4 , which is formed by a first portion and a second portion. The first portion is formed by a main housing part  1  and a housing cover  2 , the second portion is formed by silicone linings  3  and  4 . In the present embodiment, the silicone linings  3  and  4  in each case are moulded onto the main housing part  1  and the housing cover  2  of the housing  1 ,  2 ,  3 ,  4 . The basic shape of the housing  1 ,  2 ,  3 ,  4  here is thus predetermined substantially by the main housing part  1  and the housing cover  2 . The housing  1 ,  2 ,  3 ,  4  forms an interior space  7  which serves to guide the hot liquid. Moreover, the housing  1 ,  2 ,  3 ,  4  in the present exemplary embodiment is closable by two closure elements in the form of a closure cover  5  and a closure plug  6 . In the present exemplary embodiment, the interior space  7  is thus delimited jointly by the silicone linings  3  and  4  and also by the closure cover  5  and the closure plug  6 . 
         [0042]    The silicone linings  3  and  4  are preferably each made from a material which is more liquid-repellent than the material of the main housing part  1  and the housing cover  2 . The material of the silicone linings  3  and  4  preferably has a Shore A hardness of approx. 40 to 80, and the material of the main housing part  1  and the housing cover  2  preferably has a Shore A hardness of more than 80. Moreover, the surfaces of the silicone linings  3  and  4  in each case are preferably polished. 
         [0043]    The main housing part  1 , which can be seen to good effect in particular in  FIG. 6 , has a sprinkling element in the form of a perforated plate  10  for distributing the hot liquid over the coffee powder. The perforated plate  10 , which here is circular and formed substantially in a planar manner, extends perpendicularly to the direction of gravity when the distributing head is installed as intended in a beverage maker. A multiplicity of holes  15  are formed within the perforated plate  10 , said holes being distributed in a preferably uniform manner over the perforated plate  10 . The holes  15  allow an exit of the hot water from the interior space  7  of the housing  1 ,  2 ,  3 ,  4  to the outside. In the present exemplary embodiment, said holes  15  are lined with the silicone lining  3  such that exit openings  35  are formed. The exit openings  35  here in each case have an internal diameter d which is dimensioned so that the hot water falls, preferably in the form of drops, from the outside of the exit openings  35  onto the infusion material held in the filter below the distributing head. The spatial arrangement of the holes  15  or the exit openings  35  moreover allows water to be sprinkled in as uniform a manner as possible on the infusion material. 
         [0044]    Preferably an encircling side wall  11  extends upward along the peripheral circumference of the perforated plate  10 . The transition from the perforated plate  10  to the side wall  11  here may, as in this case, take place via an encircling step. It is also possible for the side wall  11  to have a slightly conical shape which widens from the bottom upward to approximately halfway up its height and, at its upper end, merges via a slight bend into an almost cylindrical shape of the side wall  11 . The perforated plate  10  and the side wall jointly define a distribution chamber  70 , which serves to distribute the hot water, in the interior space  7 . 
         [0045]    In the vicinity of the perforated plate  10 , a rectangular recess  14 , which extends over approximately half the height of the side wall  11  and over an angular region of somewhat less than 45°, is formed in the side wall  11 . 
         [0046]    The main housing part  1  in the present exemplary embodiment additionally has an inlet duct  12 , which with its front end leads into the recess  14  of the side wall  11 . The opposite, rear end of the inlet duct  12  is designed to be open to the outside but is closable by means of the closure plug  6 . Toward the top, the inlet duct  12  is designed to be open over substantially its entire length and is closable by means of the housing cover  2 . From the base of the inlet duct  12 , two side walls lying opposite one another extend upward. As can be seen in particular in  FIG. 2 , the side walls of the inlet duct  12  in each case have a constant height over a large part of the length of the inlet duct  12 , said height being somewhat greater than half of the height of the recess  14 . However, in the vicinity of the recess  14 , the side walls of the inlet duct  12  rise in relation to the base until they terminate slightly above the recess  14  on the side wall  11 . Above the recess  14 , the side walls of the inlet duct  12  are connected to one another via a flange which projects from the side wall  11 . 
         [0047]    In the vicinity of the rear end, which can be closed with a closure plug  6 , an entry connector  13  extends from the base of the inlet duct  12  in the downward direction. The entry connector  13  here extends downward from the base of the inlet duct  12  to about level with the perforated plate  10 . With its upper end, the entry connector  13  leads into the inlet duct  12  and thus forms an inlet for the liquid into the interior space  7 . On account of a slight inclination of the inlet duct  12  in the longitudinal direction, this upper end of the entry connector  13  is located slightly above the recess  14  in relation to the direction of gravity. This has the effect that, having passed through the entry connector  13  from below, the water flows toward the perforated plate  10  on account of the effect of gravity in the inlet duct  12 . The inlet duct  12  defines a main flow direction of the hot water in the interior space  7  of the distributing head, said main flow direction extending along the longitudinal direction of the inlet duct  12 . 
         [0048]    Toward the top, the inlet duct  12  is closable by means of the housing cover  2 . The housing cover  2  has a shape which is complementary to the inlet duct  12 , on account of which the inlet duct  12 , which is closed by the housing cover  2 , has a cross section which is of rectangular shape. Preferably, the housing cover  2  is connected to the inlet duct  12  during manufacturing, in particular by means of ultrasonic welding, in such a manner that it permanently closes the inlet duct  12 . The provision of a housing cover  2  serves in particular to ensure accessibility to all inner faces of the housing  1  from the outside during manufacturing. 
         [0049]    The main housing part  1  and also the housing cover  2  are preferably each made in one piece from a plastic, in particular from a polycarbonate. In principle, however, it would also be conceivable, of course, to form the housing cover  2  directly in one piece with the main housing part  1 . 
         [0050]    Silicone linings  3  and  4  are attached on the main housing part  1  and on the housing cover  2 , respectively. In the present exemplary embodiment, these silicone linings  3  and  4  cover all inner faces of the main housing part  1  and the housing cover  2  and are preferably moulded onto the main housing part  1  and onto the housing cover  2 , respectively. The silicone lining  3 , in consequence, has a substantially identical configuration to that of the main housing part  1 . In an analogous manner to the main housing part  1 , said silicone lining  3  correspondingly has a perforated plate  30 , with exit openings  35 , a side wall  31 , which upward from the perforated plate  30  and has a recess  34 , and an inlet duct  32 , which leads into the recess  34  and has an entry connector  33 . Likewise, the silicone lining  4  has a substantially identical configuration to that of the housing cover  2 , on which said silicone lining  4  is attached. 
         [0051]    As can be seen in  FIG. 2 , the silicone lining  3  in each case covers the radial inner faces of the holes  15  of the perforated plate  10  on the inner side. The silicone lining  3  here thus extends in each case into the holes  15 , such that the inner faces of the exit openings  35  in each case are formed by the silicone lining  3 . The holes  15  here have an internal diameter D, and the exit openings  35  of the silicone lining have an internal diameter d. The internal diameter d is dimensioned so as to be smaller than the internal diameter D. Here, d is in each case dimensioned in such a manner that a droplet formation is facilitated when the hot water exits from the exit openings  35 . In specific terms, in the present exemplary embodiment an internal diameter d of the exit openings  35  of approx. 2.3 mm has been selected for this purpose. The radial thickness of the silicone lining  3  within the holes  15 , which corresponds to the difference between the internal diameters D and d, is approx. 0.6 to 0.8 mm. 
         [0052]    Whereas the silicone linings  3  and  4  have a constant thickness of approx. 1 to 2 mm in the region of the side wall  31 , the inlet duct  32  and the entry connector  33 , the perforated plate  30  of the silicone lining  4  has a varying thickness in relation to the direction of gravity of between approx. 1 to 2 mm and 4 to 5 mm. As is readily visible in  FIG. 2 , the perforated plate  30  here is formed to be thickest in the vicinity of the recess  34  and becomes thinner as the distance from the recess  34  increases, such that said perforated plate  30  forms a planar surface which is slightly inclined in relation to the direction of gravity. This slight inclination of the upper side of the perforated plate  30  has the effect that the water flowing in from the inlet duct  32  does not remain on the perforated plate  30  in the region close to the recess  34  and flow away almost exclusively via the exit openings  35  which are located in this region, but flows onward over the perforated plate  30  and also reaches the exit openings  35  which are located at a distance from the recess  34 . As a result, the water is distributed over the perforated plate  30  in an improved manner and exits from the various exit openings  35  in more uniform amounts. 
         [0053]    Flow elements  36 , which extend upward into the distribution chamber  70  and are readily visible particularly in  FIGS. 4 and 5 , are formed on the upper side of the perforated plate  30 . The flow elements  36  here are attached directly on the perforated plate  30 . In other embodiments, said flow elements  36 , however, could also be attached on the closure cover  5 , for example. The flow elements  36  serve to split up the flow of water in the distribution chamber  70  and to distribute the hot water perpendicularly to the main flow direction in a more uniform manner over the perforated plate  30 , such that said hot water exits from the various exit openings  35  in more uniform amounts. In the present case, exactly three flow elements  36  are in place. The flow elements  36  here in the plan view of  FIG. 5  in each case have substantially the shape of a wedge which is slightly rounded at the front, the tip of said wedge facing in the direction counter to the main flow direction. This wedge here has two legs which in each case enclose an angle of approx. 70°. One of the flow elements  36  here is located in the immediate vicinity of the recess  34 . In relation to a plane of symmetry which extends along the longitudinal axis of the inlet duct  32 , the flow elements  36  have a mirror-symmetrical arrangement. The two legs of the flow elements  36 , which are each spaced apart laterally from the longitudinal axis of the inlet duct  32 , are designed here to be of different lengths, the leg located closer to the plane of symmetry in each case being markedly shorter. The height of the flow elements  36  corresponds approximately to that of the recess  34 . 
         [0054]    The distribution chamber  70  is closable from above by a closure cover  5  which is insertable in a releasable manner into the upper opening of the housing  1 , said opening being defined by the side wall  11 . The closure cover  5 , which is preferably made in one piece from silicone and which is shown, in particular, in  FIG. 7 , has a closure face  50 , a side wall  51 , which extends upward from said closure face  50  in an encircling manner, and a bearing flange  52 , which extends outward from the upper edge of the side wall  51 . Sealing ribs which allow a liquid-tight connection to the side wall of the silicone lining  3  are formed on the radial outer side of the side wall  51 . The bearing flange  52  serves for bearing on the upper edge of the side wall  11  of the housing  1 . Once the closure cover  5  has been inserted into the housing  1 , the closure face  50  preferably lies against the flow elements  36 . 
         [0055]    The rear end of the inlect duct  12  in the present embodiment is closable in a liquid-tight manner by means of a closure plug  6 . The closure plug  6  is insertable in a releasable manner into the inlet duct  12  and is preferably made in one piece from silicone. As can be seen in  FIG. 9 , said closure plug  6  has a rectangular closure face  60  with an encircling side wall  61 , from which a bearing flange  62  extends outward. The side wall  61  on its outer side has sealing ribs which allow a connection to the inner face of the inlet duct  32 . The bearing flange  62  serves for bearing on the rear edge of the inlet duct  12 , once the closure plug  6  has been fully inserted into the inlet duct  12 . 
         [0056]    The invention is, of course, not limited to the present exemplary embodiment, and a large number of modifications are possible. By way of example, it is not absolutely necessary for the silicone linings  3  and to form all liquid-carrying inner faces of the distributing head. It suffices if, for example, one silicone lining is attached in particular in the region of the holes  15 , that is to say within the holes  15  and/or on the inner side of the perforated plate  10 . Moreover, the lining need not be made from silicone, but may be made from another material which is more liquid-repellent in comparison with the main housing part  1 . The flow elements  36 , the closure plug  6  and the closure cover  5  in each case may be configured in any other manner or may even be dispensed with altogether. The presence of an inlet duct is also not absolutely necessary. Instead of being on an inlet duct, the inlet for the water into the distributing head could, for example, also be located directly above the perforated plate. The housing cover  2  need not necessarily be present and could also be formed for example, in particular from the outset in one piece with the main housing part  1 . Welding together the housing cover and the main housing part during manufacturing would then no longer be necessary. A large number of further modifications are possible. 
       LIST OF REFERENCE SIGNS 
       [0000]    
       
           1  Main housing part 
           10  Perforated plate 
           11  Side wall 
           12  Inlet duct 
           13  Entry connector 
           14  Recess 
           15  Holes 
           2  Housing cover 
           3  Silicone lining 
           30  Perforated plate 
           31  Side wall 
           32  Inlet duct 
           33  Entry connector 
           34  Recess 
           35  Exit openings 
           36  Flow elements 
           4  Silicone lining 
           5  Closure cover 
           50  Closure face 
           51  Side wall 
           52  Bearing flange 
           6  Closure plug 
           60  Closure face 
           61  Side wall 
           62  Bearing flange 
           7  Interior space 
           70  Distribution chamber