Solid detergent dispenser attached to a dishwasher rack

Abstract

An apparatus for dispensing a detergent solution from a solid detergent into a dishwasher can be attached to a dishwasher rack around a perimeter of the rack and collect water in the dishwasher and use the collected water to produce the detergent solution by dissolving a portion of the solid detergent. In various embodiments, the apparatus can include a detergent chamber to accommodate the solid detergent and optionally an end-of-detergent indicator to indicate an amount of the solid detergent in the detergent chamber. In various embodiments, release of the detergent solution can be controlled passively using size of a liquid outlet or actively using operational state of the dishwasher and/or a sensed signal indicative of the concentration of the detergent in the dishwasher water.WO

1 . An apparatus configured to be attached to a dishwasher rack and to dispense a solid detergent, the rack configured to be removably placed in a dishwasher capable of performing cleaning cycles, the apparatus comprising:
 a frame including:
 inner edges to be detachably connected to the rack around a perimeter of the rack; 
 a detergent chamber to accommodate the solid detergent; 
 a liquid inlet in fluid communication with the detergent chamber to allow a flow of water into the detergent chamber to at least partially dissolve the solid detergent in the detergent chamber; and 
 a liquid outlet in fluid communication with the detergent chamber to allow a flow of the detergent solution out of the detergent chamber. 
   
     
     
         2 . The apparatus of  claim 1 , wherein the frame is configured to be detachably attached to the rack with a snap. 
     
     
         3 . The apparatus of  claim 1 , wherein the frame comprises a hollow frame formed by a frame wall having an interior surface defining the detergent chamber, and the liquid inlet and the liquid outlet each comprise one or more holes on the frame wall. 
     
     
         4 . The apparatus of  claim 3 , wherein the frame further comprises an end-of-detergent indicator including a transparent window incorporated onto the detergent chamber to allow for observation of an amount of the solid detergent in the detergent chamber. 
     
     
         5 . The apparatus of  claim 3 , wherein the frame further comprises an end-of-detergent indicator including a detergent sensor configured to sense a detergent level signal indicative of a level of the solid detergent remaining in the detergent chamber, the end-of-detergent indicator configured to indicate an end of detergent in response to the sensed detergent level signal indicating that the level is below a threshold level. 
     
     
         6 . The apparatus of  claim 5 , wherein the detergent sensor comprises a conductivity sensor configured to sense a concentration signal indicative of a concentration of the detergent in the detergent chamber, and the end-of-detergent indicator is configured to indicate the end of detergent in response to the sensed concentration signal falling below a threshold concentration. 
     
     
         7 . The apparatus of  claim 1 , wherein the frame further comprises a dispensing control unit configured to actively control a volume of the flow of the detergent solution out of the detergent chamber. 
     
     
         8 . The apparatus of  claim 7 , wherein the dispensing control unit comprises:
 a cleaning cycle detector configured to detect an operational state signal indicative of an operational state of the dishwasher;   a valve coupled between the detergent chamber and the liquid outlet, the valve configured to be driven by a release signal; and   a valve controller configured to generate the release signal using the sensed operational state signal, the release signal causing the valve to release a specified volume of the detergent solution for each cleaning cycle of the cleaning cycles.   
     
     
         9 . The apparatus of  claim 7 , wherein the dispensing control unit comprises:
 a conductivity sensor configured to sense a concentration signal indicative of a concentration of the detergent in the dishwasher;   a valve coupled between the detergent chamber and the liquid outlet, the valve configured to be driven by a release signal; and   a valve controller configured to generate the release signal when the sensed concentration signal indicates that the concentration is below a threshold concentration.   
     
     
         10 . A system for dispensing a detergent solution from a solid detergent into a dishwasher capable of performing cleaning cycles, the system comprising:
 a dishwasher rack configured to be removably placed in the dishwasher; and   a frame including:
 inner edges to be connected to the rack around a perimeter of the rack; 
 a detergent chamber to accommodate the solid detergent; 
 a liquid inlet in fluid communication with the detergent chamber to allow a flow of water into the detergent chamber to at least partially dissolve the solid detergent in the detergent chamber; and 
 a liquid outlet in fluid communication with the detergent chamber to allow a flow of the detergent solution out of the detergent chamber. 
   
     
     
         11 . The system of  claim 10 , further comprising the solid detergent, wherein the solid detergent includes a detergent agent and a rinse aid agent and is in a form of tablets or pellets. 
     
     
         12 . The system of  claim 10 , wherein the rack is a rectangular rack having four sidewalls and a bottom panel coupled to the four sidewalls, and the frame includes four inner edges each connected to a portion of a sidewall of the four sidewalls of the rack when the frame is attached to the rack. 
     
     
         13 . The system of  claim 12 , wherein the inner edges are configured to be detachably connected to the rack around the perimeter of the rack, such that the frame is configured to be detachably attached to the rack. 
     
     
         14 . The system of  claim 13 , where the frame further comprises a dispensing control unit configured to controllably release the detergent solution from the detergent chamber to the liquid outlet, the dispensing control unit including:
 a cleaning cycle detector configured to detect an operational state signal indicative of an operational state of the dishwasher;   a valve coupled between the detergent chamber and the liquid outlet, the valve configured to be driven by a release signal; and   a valve controller configured to generate the release signal using the sensed operational state signal, the release signal causing the valve to release a specified volume of the detergent solution for each cleaning cycle of the cleaning cycles.   
     
     
         15 . The system of  claim 13 , where the frame further comprises a dispensing control unit configured to controllably release the detergent solution from the detergent chamber to the liquid outlet, the dispensing control unit including:
 a conductivity sensor configured to sense a concentration signal indicative of a concentration of the detergent in the dishwasher;   a valve coupled between the detergent chamber and the liquid outlet and to be driven by a release signal; and   a valve controller configured to generate the release signal when the sensed concentration signal indicates that the concentration is below a threshold concentration.   
     
     
         16 . The system of  claim 10 , where the frame further comprises an end-of-detergent indicator including a detergent sensor configured to sense a detergent level signal indicative of a level of the solid detergent remaining in the detergent chamber, the end-of-detergent indicator configured to indicate an end of detergent in response to the sensed detergent level indicating that the level is below a threshold level. 
     
     
         17 . A method for operating a detergent dispensing system in a dishwasher capable of performing cleaning cycles each including washing and rinsing periods, the method comprising:
 holding a solid detergent in a detergent chamber inside a frame configured to be attached to a dishwasher rack, the rack removably placed in the dishwasher, the frame surrounding a perimeter of the rack when being attached to the rack;   collecting a portion of water sprayed into the dishwasher during the washing and rinsing periods using a liquid inlet on the frame;   using the collected portion of water to form a detergent solution in the detergent chamber by at least partially dissolving the solid detergent; and   releasing the formed detergent solution from the detergent chamber using a liquid outlet on the frame.   
     
     
         18 . The method of  claim 17 , wherein holding the solid detergent comprises holding tablets or pellets of a combination of detergent and rinse aid agents. 
     
     
         19 . The method of  claim 17 , wherein releasing the formed detergent solution from the detergent chamber comprises releasing the formed detergent solution from the detergent chamber through one or more holes on the frame, the one or more holes sized to control a volume of the formed detergent solution to be released. 
     
     
         20 . The method of  claim 17 , wherein releasing the formed detergent solution from the detergent chamber comprises releasing a specified volume of the detergent solution from detergent chamber for each cleaning cycle of the cleaning cycles. 
     
     
         21 . The method of  claim 17 , wherein releasing the formed detergent solution from the detergent chamber comprises:
 sensing a conductivity signal indicative of a concentration of the detergent in a liquid in the dishwasher using a sensor incorporated into the frame; and   controlling the release of the detergent solution from the detergent chamber using the conductivity signal.   
     
     
         22 . The method of  claim 17 , further comprising:
 monitoring a level of the solid detergent remaining in the detergent chamber; and   producing an end-of-detergent alarm using an outcome of the monitoring.