Patent Publication Number: US-2020277725-A1

Title: Dispensing Mechanism For Dispensing Tablets Of A Washing Product

Description:
The present invention relates to a dispensing mechanism for dispensing tablets of a washing product. The product may be a detergent or a laundry additive (e.g. bleach or fabric softener). 
     It is particularly designed for a washing machine. In such machines the washing product may be dispensed directly into a washing drum. However, washing machines are also provided with a drawer mechanism into which detergent is placed by a user. The detergent may be in a number of physical forms including powder, tablet, liquid or liquid capsule. 
     These dispensing methods all suffer from a number of problems in that a number of these allow the possibility of the user coming into contact with the washing product which is generally best avoided as it is messy and potentially harmful. Further, the use of tablets and capsules provides no active control during the washing cycle of the release of the product. 
     The present invention addresses these problems. 
     According to the present invention there is provided a dispensing mechanism for dispensing tablets of washing product into a washing machine as set out in claim  1 . 
     By providing the tablets in a storage module, the user can be protected from coming into contact with these during the dispensing operation. Further, by housing a plurality of tablets within the storage module, there is no need for a user to add more product to the machine for each separate washing cycle as the module can be arranged to dispense across a number of washing cycles. Also, the fact that the dispensing is determined by a screw dispenser which is selectively operable means that the tablets can be dispensed into the washing machine at optimum times during the washing cycle. 
     The dispensing module may be integrated into the washing machine. Alternatively the dispensing mechanism may be designed as a stand-alone cartridge which can be placed into the drawer of a washing machine. In this case, the dispensing module is preferably provided with an attachment means for attachment to the washing machine. This may, for example, be in the form of a hook which is designed to hook onto a complimentary part of a drawer in the washing machine. Because the storage module is releasably attachable to the dispensing module, once in place the dispensing module can be left in situ and the storage module can be removed and either refilled or replaced. 
     The opening in the storage module is preferably provided with a closure. This may be in the form of a removable cap or the like to prevent the tablets from falling out during storage and transportation, to prevent moisture reaching the tablets and to prevent the user from coming into contact with the tablets. Preferably, however, the opening is covered by a pierceable membrane and the dispensing module is provided with a piercing element to piece the membrane. This ensures that the tablets are not exposed to the external environment until the dispensing module is attached to the storage module. Preferably the piercing member is in the form of a raised edge surrounding the opening. The raised edge preferably extends further on one side of the opening than the other so as to provide a progressive cutting effect on the membrane. 
     The screw dispenser may be rotated through a number of predetermined turns in order to dispense a predetermined number of tablets. Preferably, however, a sensor is provided to detect the number of tablets which have actually been dispensed. This may be coupled to a controller which is configured to continue to operate the screw dispenser until the required number of tablets have been dispensed. 
     The tablets may be sized with the intention to dispense one per wash cycle. However, preferably they are sized to require several per washing cycle. This allows flexibility to add additional tablets at appropriate points in the wash cycle. 
     The dispensing module may be couplable to a power supply within the washing machine. However, in the case of the stand-alone module, the dispensing mechanism is preferably provided with a battery to provide power to the motor. 
     The dispensing mechanism is preferably connectable to a remote device, via, for example, WIFI or Bluetooth. This allows the device to communicate with a washing machine controller and/or a remote user interface such as a mobile phone or tablet. 
     The dispensing mechanism may comprise two or more storage modules each having an associated dispensing module, wherein each storage module contains a different washing product. This allows different products to be dispensed at different points in the washing cycle. 
    
    
     
       An example of a dispensing mechanism will now be described with reference to the accompanying drawings, in which: 
         FIG. 1  is a schematic cross section through the dispensing mechanism in the drawer; 
         FIG. 2  is a perspective view of the storage module; 
         FIG. 3  is a similar view to  FIG. 2  with the housing shown to be transparent to show the tablets within the module prior to use; 
         FIG. 4  is a perspective view of the drawer of a washing machine and the dispensing module prior to insertion; 
         FIG. 5  is a view similar to  FIG. 4  showing the attachment of the storage module; and 
         FIG. 6  is a view similar to  FIG. 5  showing the storage module in its final position. 
     
    
    
     As shown in  FIG. 1 , the dispensing mechanism consists of two main components namely a storage module  1  and a dispensing module  2  which are connected one above the other as shown in  FIG. 1 . 
     The dispensing module  1  comprises a housing  3  containing a plurality of tablets  5  (in this case  40 ) of detergent. These may have any suitable shape but are shown in the present example as having a curved bottom which enables them the move more easily within the storage module  1 . They may also have a substantially spherical shape so that they roll. 
     The housing  3  has a sloped floor  6  which is sloped towards an opening  7  via which the tablets  5  are selectively dropped into the dispensing module  2 . 
     Prior to being placed in the position shown in  FIG. 1 , the opening  7  is closed by a pierceable membrane  8  depicted schematically in a dashed line in  FIG. 1 . 
     The dispensing module  2  has a housing  10  which defines a screw chamber  11  containing a screw  12 . The screw  12  is mounted to rotate about a horizontal axis in the direction of the arrow R such that rotation of the screw  12  will push a tablet  5  to the right as shown in  FIG. 1 . 
     The housing further comprises a dispensing opening  13  in the lowermost face of the housing  3  through which a tablet  5  can be dropped out of the dispensing module  2  and into the washing machine. 
     The dispensing module  2  has a hook  14  for an attachment to a corresponding lip in the drawer D of the washing machine. A similar hook may be present on the opposite side. Alternatively a number of other engaging features maybe provided which will mate with corresponding features in the drawer D. These may include recesses in the dispensing module  2 , or the dispensing module  2  being an interference fit within the drawer. 
     Towards the end of the dispensing module  2  opposite to the dispensing opening  13  is a motor housing  15  which houses a motor  16  powered by a battery  17 . 
     The upper surface of the dispensing module  2  is provided with a number of engagement features to locate with respect to the storage module  1 . These include an upstanding lip  18  which surrounds the periphery of the lower portion of the storage module  1 . There is also a recess  19  which locates with respect to a downwardly depending skirt  20  in the bottom of the storage module  1 . The piercing member  21 , in the form of an upstanding boss with a sharp upper edge, projects upwardly from the top of the module  2  and surrounds the opening  7 . As is apparent from  FIGS. 1 and 4 , this projects to a greater extent on one side of opening  7  so that it progressively engages with a small part of the membrane  8  at any one time thereby facilitating the cutting process. It may also be configured to follow the line of the sloped floor  6 . In  FIG. 1 , it is shown with a lip projecting slightly above the floor  6  on the right hand side but, in practice, this lip may be eliminated. 
     In an alternative example, the dispensing module  2  may be built into the washing machine, for example, in the drawer. In this case, the dispensing module  2  will be provided with an upper surface similar to that described to engage with the storage module  1  which will be attachable in the same way. However, rather than having an on board power supply, it may be powered from the power supply of the washing machine. 
     A sensor  22  which is, for example, an optical sensor, IR sensor or a contact switch is provided adjacent to the opening  13  to detect when a tablet has been dropped from the opening  13 . This is connected to a controller (not shown) which can be programmed to dispense a certain amount of tablets and can then switch off the motor  16  once the sensor  22  determines that the desired number of tablets have been dispensed. The sensor  22  and controller are powered by the battery  17 . 
     The controller may also be provided with remote communication via, for example, WIFI or Bluetooth to allow it to communicate with a washing machine controller or a user interface such as a smartphone. 
     In order to use the device, in the case of the stand-alone device according to the present example, the dispensing module  2  is first inserted into the drawer D of the washing machine as shown in  FIG. 4 . The hook  14  engages with a lip on the drawer in order to retain the dispensing module  2  firmly in place. 
     The storage module  1  is then inserted as shown in  FIG. 5  with the leading edge being inserted first as shown in  FIG. 5  before the opposite end is pushed into place. Particularly when the dispensing mechanism, is used for the first time, the dispensing module  2  and storage module  1  may alternatively be assembled together before being placed in the drawer. 
     The uniting of the storage module  1  and dispensing module  2  causes the piercing mechanism  21  to pierce the film  8  thereby allowing a first tablet  5  to drop into the dispensing module  2  and onto the screw  12 . It should be noted that the film  8  is a very thin membrane which is intended to be almost completely severed by the piercing mechanism  21 , but which remains attached only by a small portion of the periphery of the opening  7  such that it does not drop into the dispensing module  2 . The membrane  8  is very thin such that it will not prevent the tablets  5  from passing through the opening  7 . 
     When a tablet  5  is to be dispensed, this may be determined by the controller from a remote signal or may be determined in some other way such as by determining the passage of a certain amount of time from the beginning of the machine cycle or may be manually activated by a user operable switch. The number and timing of the tablets dispensed will depend to a large extent on the size of the load and the washing program selected by the user. The motor  16  will then rotate the screw  12  driving the tablets  5  to the right as shown in  FIG. 1  until one reaches the opening  13  whereupon it will drop through the opening. This is detected by the sensor  22 . If further tablets are required, the motor  16  continues to rotate the screw  12  until the required number are dispensed. Otherwise, the controller determines that the dispensing operation is complete for the time being it will stop the operation of the motor  16 . 
     The dispensing mechanism is preferably provided with a means of determining when the storage module  1  is empty. This may be done, for example, by the sensor  22  counting the total dose which has been dispensed since the storage module was fitted. Alternatively it may be caused by the sensor  22  determining that no tablets are being dispensed even though the screw  12  is being turned. This empty status may be communicated to the user via an alarm such as a light or sound, or as a communication with the user interface via the wireless connection. 
     The storage module  1  is then removed and is replaced by a full one and the above operation is then repeated. 
     A typical formulation for the tablet is as follows: 
     Bleach: Sodium Percarbonate 
     Bleach activator: TAED, Tetraacetylethylenediamine 
     Enzymes: Protease, mannanase, lipase, pectinase, cellulose 
     Surfactants: non-ionic and anionic 
     Tableting agents: PEG6000, microcrystal cellulose, talcum 
     Dissolution agent: Citric acid 
     Independently of the formulation, each tablet preferably has a volume of 800 to 2500 mm 3 , and preferably 850 to 2200 mm 3 . Each tablet preferably has a mass of 1 to 4 g.