Abstract:
A brewing system includes a brewing apparatus and a capsule containing a substance for brewing. The capsule has an opening on one side and a base on an opposite side. The base includes a light input surface, a light-output surface and a light conductor to conduct light from the light input surface to the light output surface. The apparatus includes: a brewing chamber including an inlet for heated water, an outlet for the brewed beverage, and an opening in communication with the opening of the capsule. A light source on the brewing apparatus emits light into the base via the light inlet surface of the capsule. The light conductor conducts the light to the light-output surface. A light detector of the brewing apparatus detects light emitted by light-output surface on the base of the capsule. A method of operating the brewing system and a capsule system are also described.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a U.S. National Stage Application of International Patent Application No. PCT/EP2015/062362, filed Jun. 3, 2015, which claims benefit of German Patent Application No. 10 2014 109 768.8, filed Jul. 11, 2014. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to an apparatus for preparing brewed beverages, comprising a brewing chamber, on which an inlet is provided for heated water and an outlet for the brewed beverage, wherein the brewing chamber has an opening on which a capsule can be arranged with substances effective for the brewing operation, the capsule having a capsule opening which is connected at least in part to the brewing chamber and a base opposite the capsule opening, and to a capsule, a capsule system for the apparatus, and a method for producing a brewed beverage. 
       BACKGROUND OF THE INVENTION 
       [0003]    EP 1 786 303 discloses an apparatus for preparing a beverage which comprises a detection device for recognising an identification marking on a portion package. The detection device is arranged on a sliding rail for guiding the portion package and carries out a colour recognition in that reflected light of a diode is detected. Such detection is susceptible to errors, especially when the package is soiled on the exterior side or the colours on the packages reflect light in a similar frequency spectrum. 
         [0004]    WO 2007/087890 discloses a further apparatus for preparing hot beverages, in which a detection unit is provided for reading out a code provided on the cartridges. The detection unit comprises a radiation emitter and a radiation detector, wherein the radiation is guided through the edge of a cartridge. Means for coding are provided on the edge, so that recognition of the cartridge can occur. It is also disadvantageous in this recognition system that the edge of the cartridge is gripped during use for insertion of the cartridge and can therefore be soiled very easily. This can lead to errors in the recognition. Furthermore, the cartridge edge can also be slightly deformed or damaged. 
       SUMMARY OF THE INVENTION 
       [0005]    It is therefore the object of the present invention to provide an apparatus for preparing brewed beverages which allow reliable recognition of coding on a capsule. Furthermore, a capsule shall be provided for such an apparatus and a capsule system. 
         [0006]    This and other objects are achieved by a brewing system including an apparatus for preparing a brewed beverage and a capsule having an interior space for containing a substance effective for a brewing operation by the system, the capsule further comprising: a side having an opening and a base on a side opposite the side with the opening, the base including a light input surface, at least one light output surface and at least one light conductor to conduct light from the light input surface to the at least one light output surface, the capsule being adapted to be connected to a brewing chamber of the apparatus; and the apparatus comprising: a brewing chamber including an inlet for heated water, an outlet for the brewed beverage, and an opening in communication with the opening of the capsule when the capsule is connected to the brewing chamber; at least one light source arranged to be adjacent to the base of the capsule when the capsule is arranged on the brewing chamber, wherein the light source is operative to emit light into the base via the light inlet surface of the capsule, wherein the at least one light conductor on the base of the capsule conducts the light emitted into the base to the at least one light-output surface on the base of the capsule; and at least one light detector arranged opposite the at least one light-output surface of the capsule when the capsule is arranged on the brewing chamber, to detect light emitted by the at least one light-output surface on the base. 
         [0007]    The object is also achieved by a capsule including an interior space for containing a substance effective for a brewing operation in an apparatus having a brewing chamber for brewing a beverage, the capsule, in one embodiment, further including: a side having an opening and a base on a side opposite the side with the opening, the base including a light inlet surface, at least one light output surface and at least one light conductor to conduct light from the light input surface to the at least one light output surface, wherein the capsule is adapted to be connected to the brewing chamber of the apparatus such that the opening on the side of the capsule is in communication with an opening in the brewing chamber of the apparatus. 
         [0008]    The object is further achieved by a capsule system for a brewing system as above described wherein a plurality of capsules are provided in which at least one of the light-output surfaces and the light inlet surface of one capsule have different light transmission characteristics compared to the light-output surfaces and the light inlet surface of the other capsules in the plurality of capsules. 
         [0009]    The object is further achieved by a method for preparing a brewed beverage, which in one embodiment, includes the following steps: providing a capsule containing a substance effective for a brewing operation in an apparatus having a brewing chamber for brewing a beverage, wherein the capsule has a base including a coding and at least one light conductor by which light emitted into the base is conducted to at least one light-output surface on the base; inserting the capsule into an insertion chute of the apparatus and arranging the capsule adjacent to the brewing chamber; arranging at least one light source adjacent to the base of the inserted capsule to emit light into the base of the capsule; reading out the coding on the base of the capsule with a light detector arranged opposite the at least one light-output surface; and filling hot water into the brewing chamber for preparing a brewed beverage depending on the coding read by the light detector. 
         [0010]    At least one light source is provided in accordance with the invention for capsule recognition adjacent to the base of the capsule, which light source emits light into the base via an inlet surface, wherein at least one light conductor is provided in the base by means of which the light emitted into the base is conducted to at least one light-output surface on the base of the capsule, and a light detector is arranged opposite the at least one light-output surface. As a result, the function of capsule recognition can be shifted completely to the base of the capsule, which is far less susceptible to soiling than a protruding edge or any other exterior surface on the capsule, which is gripped during use and can be soiled. Furthermore, capsule recognition is reliable because detection occurs via light which is introduced into the base of the capsule and is output on at least one light-output surface. Light detectors can thus be used which are not susceptible to errors during detection, even in the case of minor soiling on the base. 
         [0011]    According to a preferred embodiment of the invention, several light conductors are provided in the base into which light can be conducted from an inlet surface to a light-output surface on the base of the capsule. A light deflection apparatus can be provided in the base of the capsule adjacent to an inlet surface and/or a light-output surface. This allows recognising a capsule with only one light source and several light detectors or one light detector and several light sources. 
         [0012]    For the purpose of an especially compact configuration, a first light deflection apparatus can be provided in each light conductor after the inlet surface and a further second light deflection apparatus before the light-output surface in order to emit the light from the light conductor to the light detectors. The light conductor can thus be arranged in a very flat way within the base so that the coding and the detection means do not disturb the user. The light can be emitted to the light detector substantially perpendicularly to a plane of the base, so that, originating from the light source, a deflection of the light occurs by approximately 180°, preferably in a range of between 140° and 220°. The light can be conducted within the base substantially parallel or at a slight angle of less than 30° relative to the plane of the base, so that the base is formed in a flat way. In addition, this arrangement allows that the light-emitting and light-receiving elements can be positioned adjacent to each other in one plane. 
         [0013]    Four light conductors are preferably provided for recognition of different types of capsules, which conduct the light from an inlet surface to four light-output surfaces or from four inlet surfaces to one light-output surface. 
         [0014]    For the purpose of secure recognition, the apparatus preferably comprises a positioning device which interacts with a positioning means of the capsule in order to arrange the capsule in a predetermined position and orientation on the brewing chamber. Capsule recognition then occurs in the position adjacent to the brewing chamber in order to process the information for the brewing process. The apparatus preferably comprises a controller for this purpose, which on the basis of the information of the light detectors controls parameters for the brewing process such as the brewing time, the temperature of the introduced water or further parameters. 
         [0015]    In accordance with the invention, a capsule is also provided for an apparatus for preparing brewed beverages, which capsule comprises at least one light conductor on the base in order to conduct the light emitted by the apparatus to at least one light-output surface on the base of the capsule. This allows detection of the capsule in a manner which is not susceptible to disturbances. The capsule preferably has reduced transparency on at least one inlet surface and/or light-output surface. It can thus be detected for the coding on the light detector whether the light-output surface is transparent, transparent to a limited extent or not at all. A coating, a label, or a mechanical, thermal or chemical change made to the surface can be provided on at least one inlet surface and/or light-output surface for reducing the transparency. The light detector will then recognise that a cover is present on the light-output surface and thus no light is detected which is adequate for determining the type of capsule. 
         [0016]    The light detector preferably measures the light intensity of the light emitted from the light-output surface, so that a decrease in the transparency can be obtained by a change in the region of the beam path of the light from the light source to the light detector. It is also possible to machine the light conductor to reduce transparency instead of the inlet surface and the light-output surface. For example, an incision or a groove can be introduced into the light conductor so as to disturb the beam path from the inlet surface to the light-output surface and thus obtain a coding of the capsule. 
         [0017]    If four light-output surfaces are provided on the capsule, it is possible to recognise during capsule recognition on the light-output surface of four light conductors whether they are transparent or non-transparent. This allows providing a capsule system with 16 different types of capsules, which represents a sufficient spectrum for most brewed beverages. 
         [0018]    The capsule is preferably formed in a substantially cup-shaped manner and comprises a capsule opening which is sealed by a screen or a filter element in a liquid-tight manner. Communication with an interior space of the brewing chamber can thus occur via the capsule opening, while capsule recognition occurs on the opposite side on the base. 
         [0019]    In accordance with the invention, a capsule system is also provided for an apparatus in which several capsules are provided which are formed differently on the light-output surfaces. 
         [0020]    In a method for producing a brewed beverage, a capsule is inserted at first into an insertion shaft and arranged adjacent to a brewing chamber. A coding on the capsule is then read out, wherein at least one light source is provided adjacent to a base of the capsule, which light source emits light into the base, wherein at least one light conductor is provided in the base by means of which the light emitted into the base is conducted to the at least one light-output surface on the base of the capsule and a light detector for reading out the coding is arranged opposite the at least one light-output surface. Hot water is then filled into the brewing chamber for producing a brewed beverage depending on the read-out coding. 
         [0021]    Several light sources can preferably be provided in the method, which after the arrangement of the capsule adjacent to the brewing chamber subsequently emit light in a successive manner to different positions in the base and the emitted light is conducted to and detected by a single light detector. A coding can be read out by only one single light detector, wherein the introduction of light into the inlet surfaces on the base can occur in a time-staggered manner, so that a controller connected to the light detector knows which light conductor is currently queried by the introduction of light. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    The invention will be explained below in closer detail by reference to an embodiment shown in the enclosed drawings, wherein: 
           [0023]      FIG. 1  shows a schematic view of an apparatus according to the invention for preparing brewed beverages; 
           [0024]      FIG. 2  shows a schematic view of the capsule recognition of the apparatus of  FIG. 1 ; 
           [0025]      FIGS. 3A to 3C  show several views of a capsule in accordance with the invention; 
           [0026]      FIG. 4  shows a modified embodiment of a capsule, and 
           [0027]      FIG. 5  shows a view of a further modified embodiment of a capsule. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0028]    An apparatus  1  for preparing brewed beverages comprises a removable collecting container  2  which is arranged in a housing. A support  3  with openings for depositing a vessel  4  is arranged on the collecting container  2 . A gripping section  5  for pulling out the collecting container  2  is provided beneath the support  3 . 
         [0029]    The apparatus  1  for preparing brewed beverages further comprises a brewing chamber  6 , which is provided adjacent to an insertion chute  7  for capsules. 
         [0030]    As is shown in  FIG. 1 , the insertion chute  7  for capsules is disposed between the brewing chamber  6  and a drive device  8 . The brewing chamber  6  can be moved relative to the insertion chute  7  via the drive device  8 . An electric motor  80  is provided for this purpose, which drives a spindle  81  via a gear, on which spindle a spindle nut  82  is mounted in a torque-proof manner. Arms which are connected to the spindle nut  82  are displaced linearly along a guide  83  by rotation of the spindle  81 . The arms engage around the brewing chamber  6  on opposite sides and can be move them linearly. 
         [0031]    The apparatus  1  for preparing brewed beverages further comprises a tank (not shown) for freshwater, which can be formed in a removable manner. The tank is provided with a pump, by means of which water is conveyed to a heating device, which is connected to an inlet line  13  above the brewing chamber  6 . 
         [0032]    A capsule  15  is provided in the insertion chute  7 , which capsule is formed in a cup-like manner and comprises an opening on one side which is sealed with a screen. The screen  31  is fixed to an edge  16  which is formed in an asymmetric manner and comprises a protruding section  17  on one side with a positioning means. The capsule  15  is thus inserted in a predetermined position and orientation into the insertion chute  7 , which comprises a respective recess with guide means for the positioning of the capsule  15 . On the side opposite the opening, the capsule  15  comprises a base  18  on which markings are arranged for identifying the capsule  15 . By reading the coding of the capsule  15  on the apparatus, the filling quantity of hot water for the brewing chamber  6 , the temperature and the dwell time can be set via a controller. The control of other parameters via the coding is also possible. 
         [0033]    The capsule  15  is inserted at first into the insertion chute  7  for the brewing process. The capsule  15  slides downwardly until it is arranged at a lateral opening  20  of the brewing chamber  6 . Retainers  19  are provided for this purpose on the exterior side of the brewing chamber  6 , which retainers prevent that the capsule  15  slips out in the downward direction.  FIG. 1  shows the brewing position to which the brewing chamber  6  is moved via the electric motor  80  after the insertion of the capsule  15 , as shown by the arrow. A seal is thus pressed adjacent to the opening on the brewing chamber  6  against the edge  16  of capsule  15 . The capsule  15  and an interior space  21  of the brewing chamber  6  thus form a unit, wherein the interior space  21  of the brewing chamber  6  and the interior of the capsule  15  are separated from each other by the screen  31 . The interior space  21  of the brewing chamber  6  is several times larger than an interior space of the capsule  15 , e.g. more than four times as large, so that the brewing beverage is mainly disposed in the brewing chamber  6  and only a minor portion in the capsule  15 , which simplifies the dispensing of the brewing beverage. 
         [0034]    In the brewing position, hot water is introduced via the inlet line  13  from the heating device  11  into the brewing chamber  6 , for which purpose a nozzle  14  is provided at the end of the inlet line  13  which protrudes with a tip into the interior space  21  of the brewing chamber  6 . The brewing chamber  6  without the capsule can accommodate a volume of between 0.1 l to 1.0 l, especially 0.15 l to 0.7 l, depending on the number of portions of the brewed beverage that need to be prepared simultaneously. The brewing chamber  6  comprises an outlet  22  at the bottom end, which outlet is connected via a line  24  to a valve  23 . The introduced hot water is collected in the brewing chamber  6  by closing the valve  23  and rises over the outlet  22  in order to reach the material contained in the capsule  15  for brewing a beverage, especially tea. The preparation of the brewed beverage can be adjusted individually via the controller by previous reading of the coding on the capsule  15  via a reader device  35 , e.g. green tea can be prepared differently than black tea, fruit tea or any other brewed or infusion beverage. 
         [0035]    The valve  23  can be opened after the brewing process so that the brewed beverage flows from the brewing chamber  6  via the outlet  22  and the line  24  into an outlet nozzle  25 , from where it is introduced into a vessel  4 . A passage  26  or an opening is disposed between the outlet nozzle  25  and the vessel  4 , so that the hot beverage can flow without obstruction into the vessel  4 . The valve  23  can be closed again after the preparation of the brewed beverage. 
         [0036]    After the brewing process, the brewing chamber  6  can be displaced via the drive device  8  away from the capsule  15  so that the capsule  15  is removed from the holding position adjacent to the lateral opening  20  on the brewing chamber  6  and drops in the downward direction. The capsule  15  drops into the collecting container  2  and onto a screen  29  or a grate which is arranged above a collecting basin  28 . The displacement of the brewing chamber  6  simultaneously also displaces the line  24  and the outlet nozzle  25 , which is now no longer arranged above the passage  26  but above a guide element  27 . The brewing chamber  6  and all other lines wetted with tea can now be rinsed, in that hot water is injected from the heating device via the nozzle  14  into the brewing chamber  6 , so that the hot water can remove residues of the brewing process. The hot water can be partly directly introduced through the opening  20  into the collecting container  2 , and is introduced otherwise via the outlet  22  and the line  24  into the outlet nozzle  25 . The rinsing water then reaches the guide element  27  from there, which is formed as a sloping surface above the vessel  4 . The rinsing water reaches the collecting basin  28  of the collecting container  2  via the guide element  27 . The guide element  27  can also be formed as a channel or a groove instead of a sloping surface. 
         [0037]      FIG. 2  schematically shows a capsule  15  which is arranged on the reader device  35 . The capsule  15  comprises an upper edge  16  on a side wall  11 , on which a capsule opening  12  is provided. The capsule opening  12  is sealed by a screen  31 , so that an extractable substance is unable to escape from the capsule  15 . 
         [0038]    A reader device  35  is provided on the base  18  on the side opposite the capsule opening  12 . The reader device  35  comprises a light source  40 , which is arranged centrally on the base  18 . Light is injected from the light source  40  on an inlet surface  41  in the middle of the base  18 , which light is distributed in light conductors  45 . A first, centrally arranged light deflection apparatus  42  is provided for this purpose, by means of which the entering light beams, which impinge substantially perpendicularly to the plane of the base  18 , are deflected at an approximately right angle and are guided through the light conductors. Several second light deflection apparatuses  43  are provided spaced from the first light deflection apparatus  42 , which second light deflection apparatuses ensure that light from the first light deflection apparatus  42  is deflected and is guided to a light-output surface  44  on the base  18 . 
         [0039]    The light-output surface  44  is arranged opposite an opening  46  or a window on a diaphragm  47 . The light reaches a light detector  36  of the reader device  35  through the opening  46 . The light detector  36  is arranged in a protected manner behind a pane  38 . 
         [0040]    Several light-output surfaces  44  are provided on the base  18 , preferably between two and eight light-output surfaces  44 , especially four light-output surfaces  44 , so that one light detector  36  is provided on the reader device  35  for each light-output surface  44 . The light detectors  36  are retained on a support  37  and connected to a controller of the apparatus  1 . 
         [0041]    It is obviously also possible to provide four light sources instead of one light source  40 , which light sources are arranged adjacent to the light-output surfaces  44 . The light-output surfaces  44  then become light injection surfaces for the light and the centrally arranged inlet surface  44  becomes a light-output surface. It is then merely necessary to arrange a single light detector adjacent to the middle inlet surface  41 , which then becomes a light-output surface. The beam direction of the light is reversed in this embodiment. The injection of light can occur in a time-staggered manner, so that readout of the individual light conductors  45  can occur separately. 
         [0042]    If light is injected into the base  18  via the light source  40 , a predetermined type of capsule can be recognised which is optionally formed in a transparent manner on the light-output surfaces  44  so that light reflected on the light detector  36  is detected, or the light-output surface  44  has a reduced transparency. A cover  48 , a label, a coating or any other means can be provided for this purpose on the light-output surface  44  in order to reduce transparency. The surface can also be changed mechanically, thermally or chemically for this purpose, so that the adjacently arranged light detector  36  does not receive any reflected light. 
         [0043]    It is also possible for reducing transparency to provide the light conductor with respective means, e.g. by one or several incisions. These means on the light conductor can also be used for encoding the capsule. 
         [0044]    A specific type of capsule is thus recognised via the reader device  35 , so that the temperature of the water to be introduced into the brewing chamber  6  and/or the brewing time or other parameters for the brewing process can be controlled. It may be useful for brewing green tea to set the brewing temperature to a lower level than in the case of black tea and to further reduce the infusion time. Optimised preparation can thus occur depending on the brewed beverage that is prepared, e.g. green tea, black tea, fruit tea, white tea or any other type of tea. 
         [0045]      FIGS. 3A to 3C  show a capsule  15  with a base  18  with light conductors  45 . An inlet surface  41  is centrally arranged on the base  18 , and light impinges on the first light deflection apparatus  42 , wherein light is injected into four light conductors  45  which are arranged in a cross-shaped manner. Four second light deflection apparatuses  43  are provided at a predetermined distance from the first light deflection apparatus  42 , which second light deflection apparatuses then emit light to four light-output surfaces  44 . 
         [0046]    The light conductors  45  are oriented substantially parallel to the plane of the base  18 , which leads to a compact configuration. In the interior region, the base  18  is thus slightly uneven in the area of the light conductors  45 , which has no disadvantageous effect on the brewing process. A cover can also be provided if necessary, so that a smooth inner base is provided on the capsule  15 . 
         [0047]    Four light-output surfaces  44  are provided in the illustrated embodiment, on which a respective light detector  36  detects or does not detect the emission of light. This leads to four types of coding on the base  18  of the capsule  15 , so that  16  different types of capsules can be recognised. It is obviously also possible to vary the number of the light-output surfaces  44  and the light detectors  36 . The light can be emitted substantially perpendicularly to a plane of the base  18  to the light detector, so that originating from the light source  40  a deflection of the light occurs about approximately 180°, preferably in a range of between 140° and 220°. The light can be conducted within the base substantially parallel or at a slight angle of less than 30° in relation to the plane of the base  18 . 
         [0048]    The light conductors  45  and the deflection apparatuses  42  and  43  can be made of transparent or translucent plastic or other suitable materials. The deflection apparatuses  42  and  43  can also be formed as mirror surfaces or reflective surfaces which deflect the impinging light in the direction. 
         [0049]    The light conductors  45  can be made only of transparent or translucent plastic, but it is also possible to provide a sheath, preferably made of a reflecting material, in order to increase the light intensity at the light-output surface. 
         [0050]    Instead of the illustrated four light-output surfaces  44 , which are arranged in a centrosymmetric manner concentric to a central point of the base  18 , other light-output surfaces can be provided, e.g. annular light-output surfaces, so that no alignment of the capsule  15  needs to occur when the capsule  15  is inserted into the insertion chute  7 . In this case, the annular light-output surfaces can be used for recognising the type of capsule. 
         [0051]    The capsule  15  comprises eccentric guide strips  49  on the base  18  and an outer edge  50 , which interact with guide means on the insertion chute  7  in order to produce guidance and alignment of the capsule  15 . 
         [0052]      FIG. 4  shows a modified capsule  15 ′, in which no guide means  49  are provided on the base  18  but only the outer edge  50 . Apart from that, the capsule  15 ′ corresponds to the preceding embodiment. 
         [0053]      FIG. 5  shows an embodiment of a capsule  15 ″ which is modified over  FIG. 3 . A centrally arranged inlet surface  41 ′ is disposed on the base  18 , which inlet surface conducts light to the first light deflection apparatus  42  so that light is injected into four light conductors  45  which are arranged in a cross-shaped manner. Furthermore, four second light deflection apparatuses  43  are provided which then emit light to four light-output surfaces  44 ′. The light-output surfaces  44 ′ and the one light injection surface  41 ′ are each arranged in a protected manner in a cup-shaped receptacle. The light-output and light injection surfaces  44 ′ and  41 ′, which are oriented parallel to the surface of the base  18 , are thus arranged in a protected manner by a downwardly protruding edge. The height of the preferably annular edge lies in a range of between 0.3 mm and 8 mm, especially 1 mm to 5 mm. Furthermore, a screen  31  is fixed to the upper edge  16  of the capsule  15 ″. 
       LIST OF REFERENCE NUMERALS 
       [0054]      1  Apparatus 
         [0055]      2  Collecting container 
         [0056]      3  Support 
         [0057]      4  Vessel 
         [0058]      5  Gripping section 
         [0059]      6  Brewing chamber 
         [0060]      7  Insertion chute 
         [0061]      8  Drive device 
         [0062]      11  Side wall 
         [0063]      12  Capsule opening 
         [0064]      13  Inlet line 
         [0065]      14  Nozzle 
         [0066]      15  Capsule 
         [0067]      16  Edge 
         [0068]      17  Section 
         [0069]      18  Base 
         [0070]      19  Retainer 
         [0071]      20  Opening 
         [0072]      21  Interior space 
         [0073]      22  Outlet 
         [0074]      23  Valve 
         [0075]      24  Line 
         [0076]      25  Outlet nozzle 
         [0077]      26  Passage 
         [0078]      27  Guide element 
         [0079]      28  Collecting basin 
         [0080]      29  Screen 
         [0081]      31  Screen 
         [0082]      32  Seal 
         [0083]      33  Projection 
         [0084]      35  Reader device 
         [0085]      36  Light detector 
         [0086]      37  Support 
         [0087]      38  Pane 
         [0088]      40  Light source 
         [0089]      41  Inlet surface 
         [0090]      42  Light deflection apparatus 
         [0091]      43  Light deflection apparatus 
         [0092]      44  Light-output surface 
         [0093]      45  Light conductor 
         [0094]      46  Opening 
         [0095]      47  Diaphragm 
         [0096]      48  Cover 
         [0097]      49  Guide strips 
         [0098]      50  Edge 
         [0099]      50  Housing 
         [0100]      80  Electric motor 
         [0101]      81  Spindle 
         [0102]      82  Spindle nut 
         [0103]      83  Guide 
         [0104]      84  Retainer