Abstract:
A drinks machine, in particular a coffee machine, with an entry device for solid cleaning agent, in particular in pressed form, being user-friendly and safe during cleaning, and having an automatically dosing, enclosed dosage device for the cleaning agent which includes a spout, a storage container protected from the spout, and at least one dosage unit.

Description:
FIELD OF THE INVENTION 
     The invention relates to a drinks machine, in particular a coffee machine. 
     BACKGROUND OF THE INVENTION 
     When drinks machines used commercially are cleaned, strict safety directives must be fulfilled to ensure that no cleaning agents remain in the machine and can then enter into the drink that is dispensed. In particular, the dosage of the cleaning agent must be observed exactly and cleaning agents should be used which represent the least load on the environment and are not a health hazard. Liquid cleaning agents can be easily dosed and can be easily handled even with automatic input. However, they contain chlorine and are therefore questionable ecologically. Cleaning agents in solid form have previously only been dosed manually, either in powder form with a measuring beaker or in pressed form as tablets, because the opinion has been that these solid cleaning agents could not be dosed in any other way due to their very strong hygroscopius effect. Solid cleaning agents in the form of powder or tablets have advantages with regard to their cleaning effect, because, due to a certain oxygen content, they give a certain effervescent effect and consequently also a mechanical cleaning effect. They also have an advantage with regard to their environmental compatibility and their toxic content. 
     SUMMARY OF THE INVENTION 
     The object of the invention is therefore to provide a drinks machine which can be simply cleaned without any problem using solid cleaning agents. 
     Using the enclosed dosing device according to this invention, solid cleaning agents can also be present, particularly in pressed form, such as for example as granulate or in the form of small tablets, and they can be safely and correctly dosed without the hydroscopic properties of this type of cleaning agent leading to problems. 
     A particularly simple and effective dosage is achieved by a movable dosage chamber which acts as a transport device for a predetermined amount of cleaning agent from the storage container to the outlet. 
     A sensor increases the safety and can be used for controlling the dosing device. 
     Further protection against undesired feeding of cleaning agent is obtained by a shut-off device. 
     The shut-off device can be actuated by the sensor to increase the safety level still further by an arrangement of the shut-off device in the direction of flow of the cleaning agent. 
     A particular advantage are design arrangements which are particularly adapted to the dosage of solid cleaning agent in granular form. It has been found that with the dosage wheel described, it is possible to correctly dose and feed safely even strongly hygroscopius granular grains without lumps forming and blockages occurring. 
     The present development, which can be separated into parts, simplifies cleaning the dosage device without impairing its enclosed properties. 
     The invention provides further protection against faulty functioning. 
     There is described a dosage device with which the present drinks machine can be retrospectively fitted. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     An embodiment of the invention is explained in more detail based on the drawings. The following are shown: 
     FIG. 1 a longitudinal section through a dosage device according to this invention in a schematic, exploded view; 
     FIG. 2 the view II—II from FIG. 1; and 
     FIG. 3 an enlarged detailed view from FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a dosage device  1 , which can be joined via a joining device  2 , shown as screws, and a support  3  to a drinks machine, not described further, in particular a normal, commercially usable and preferably automatically or semi-automatically operating coffee and tea-making machine. In the embodiment shown the dosage device  1  is permanently integrated into the drinks machine; however it can also, for example, be mounted supplementary on the drinks machine via the screws  2  and its own support  3 . 
     The dosage device  1  contains a storage container  4  with can-shaped, enclosed walls  4   a  and a joining device  5  in the vicinity of an opening  4   b  with which the storage container  4  can be mounted removably to a base section  6 . The joining device  5  can for example be a thread or a bayonet connection. 
     The base section  6  contains an essentially bowl-shaped, cylindrical housing  6   a  which accommodates the joining device  5  of the storage container  4  in its upper section and in the lower part of which a dosing wheel  7  of a dosage unit, overall designated with  8 , is arranged. The dosage wheel  7  is rotatable about its axis  7 ′, extends over the whole lower boundary of the cylindrical housing  6   a  and therefore forms the bottom of the storage container  4  if this is joined to the base section  6 . 
     The dosage wheel  7  exhibits a cone-shaped, flow-separating central section  7   a  with a separate cone tip  7   c  and a mainly radially running circumferential flange  7   b . The circumferential flange  7   b  is provided with numerous through-openings  9  distributed in the circumferential direction and formed as dosage chambers which extend in the direction of gravity perpendicular through the dosage wheel  7 . 
     At a point on the bottom of the bowl-shaped housing  6   a  is an outlet  10   a  of a spout designated overall with  10 . The outlet  10   a  is located at a point at which the outlet  10   a  can be flush with each through-opening  9  when the dosage wheel  7  rotates. Above the outlet  10   a  and above the dosage wheel  7  a scraper  11  is provided which on one side protects the through-opening  9  which is currently in flush alignment with the outlet  10   a  from the cleaning agent still flowing from the storage container  4  and which on the other side protects the storage container  4  from moist air or steam from the spout  10 . 
     The dosage wheel  7  is supported for rotation in a bearing on the bottom of the cylindrical housing  6   a  of the base section  6  and provided with gear teeth on its circumference which engage a gearwheel  13  driven by a motor  14 . 
     The motor  14  and the gear wheel  13  are mounted on the support  3  such that the base section  6  can be released with the mechanical component parts of the dosage unit  8  from the drive and cleaned. 
     Also on the support  3   a  spout pipe  10   b  for the spout is mounted which is aligned flush with the outlet  10   a  when the base section  6  is mounted on the beam  3 . In the spout pipe  10   b  a shut-off device  15  is provided which can be actuated by a lifting magnet  16  such that it alternatively shuts off or releases the spout pipe  10   b . Between the shut-off device  15  and the dosage wheel  7  there is also a sensor  17  in the form of a light barrier with which it can be determined whether cleaning agent is located in the spout  10  and in particular in the spout pipe  10   b.    
     FIG. 2 shows a plan view of the base section  6  with the dosage wheel  7  arranged in it. The dosage wheel  7  completely fills out the interior space of the cylindrical walls  6   a  and is joined over the whole cross-sectional area to the opening  4   b  of the storage container  4 . Then in particular when, as particularly preferred according to this invention, a solid cleaning agent in granular form, i.e. in the form of pressed bodies of a certain, relatively small, but mainly uniform size, is used, the through-openings  9  acting as dosage chambers have a size which is dimensioned such that they single out the granulate, i.e. they accommodate only one granulate grain. On the side facing the storage container  4  and tracking the drive direction A, each through-opening  9  is provided with a deflector recess  9   a , which narrows and flattens to the back and which simplifies the scraping of excess granulate grains by the scraper  11  and which above all ensures that the granulate grains are not where possible pulverized, which would change the dosage amount. For the same reason the through-openings  9  on the side facing the outlet  10   a  are provided with a chamfer (FIG.  1 ). 
     In FIG. 2 mounting eyes  18  can also be seen with which the base section  6  is joined to the support  3  with screws  2  enabling it to be removed. 
     In an enlarged scale, FIG. 3 shows a device designated overall with  19  for determining the filling level of a cleaning agent in the storage container  4 . The device  19  includes the separated cone tip  7   c  of the dosage wheel  7  which is loaded by a spring  20  in the direction of the storage container. The force of the spring  20  is dimensioned such that it is compressed by the weight of the cleaning agent in the storage container  4 ; and for as long as there is still enough cleaning agent in the storage container  4 . The spring  20  will therefore only push the cone tip  7   c  upwards in the direction of the arrow B when the cleaning agent in the storage container becomes used up. 
     The cone tip  7   c  is borne via a shaft  21  in a guide bush  22  on the dosage wheel  7  in which the spring  20  is also accommodated, whereby the shaft  21  extends down to the support  3  when the cone tip  7   c  is pressed onto the dosage wheel  7  by the weight of the cleaning agent in the storage container  4 . The lower end of the shaft  21  located in the vicinity of the beam is fitted with a magnet  23  which interacts with a reed switch  24  which is attached to the support  3 . When the spring  20  is able to overcome the weight of any cleaning agent remaining in the storage container  4 , the magnet  23  moves out of the actuation region of the reed switch  24 , which can be used either for an alarm and/or an indication that cleaning agent must be refilled and/or it causes future cleaning processes to be inhibited. Due to the cone-shaped form of the dosage wheel  7 , whereby the cone tip  7   c  interacting with the reed switch  24  represents the highest point, it is ensured that enough cleaning agent is still present in the region of the through-openings  9 , so that any cleaning process currently running can be terminated. 
     During the operation of the dosage device  1  according to this invention, initially the storage container  4 , filled with solid cleaning agent in granulate form, and which can also be the base section of a sales can for the cleaning agent, is joined via the joining device  5 , which, for example, can be the lid thread of this sales package, to the base section  6 . Granulate in roll form, approximate cone or roll shape or other easily dosable and transportable forms is preferred. Then the unit consisting of the storage container  4  and base section  6  is mounted overhead with the aid of the screws  2  on the support  3  to which the gear  13 , motor  14 , reed switch  24 , spout pipe  10   b  shut-off device  15 , lifting magnet  16  and the light barrier  17  are located. The electrical connections to the controller of the drinks machine can be made by any specialist and do not need to be explained in detail here. 
     If a cleaning process is now initiated, then the motor  14  is set into motion and turns the dosage wheel  7  until a specified number of through-openings  9  have passed the outlet  10   a . If, using the light barrier  17 , it is found that granulate is being fed, the storage container  4  is then full, the lifting magnet  16  is operated so that the shut-off device  15  opens the spout pipe  10   b . The granulate slides through and is either, depending on the arrangement of the dosage device  1 , introduced by gravity into the cleaning flow; or connections for compressed air or water are provided downstream in the spout pipe  10   b , which feed the granulate to the predetermined point even against gravity. 
     Since the dosage wheel  7  releases the granulate grains, according to the circumferential distance of the through-openings  9 , at intervals into the spout  10 , counting of the granulate grains can be carried out by the sensor  17 , ensuring additional protection against overdosage. 
     If the motor  14  has carried out the predetermined revolutions for correct dosage and/or the sensor  17  has established the predetermined number of granulate grains, the motor  14  is stopped and the shut-off unit  15  is closed. The lifting magnet  16  is disconnected from the current, so that protection against malfunctioning is provided. 
     However, the sensor  17  remains activated. If the presence of granulate in the spout  10  is found by the sensor  17  during a preparation cycle for a drink, then this preparation cycle is stopped by the sensor so that it is ensured that no cleaning agent enters the drink. 
     If the cleaning agent becomes used up, then the cone tip  7   c  is raised by the spring  20  and an indication occurs that the cleaning agent must be refilled. 
     In the variation of the described and drawn embodiment, a cell wheel or similar can be used instead of the perforated disc for example. It is also possible to provide only one single dosage chamber which moves between the storage container and the spout. When using a perforated disc, the scraper can cover a number of dosage chambers whereby only one single dosage chamber must be in connection with the storage container. The dosage device can also be formed in one piece and the storage container filled via a lid.