FR2658068A1 - SYSTEM FOR THE SUPPLY OF WATER AND DETERGENT OF A DISHWASHER. - Google Patents

Abstract

The system comprises a liquid detergent dispenser device 9 mounted in a side wall 2 of the machine 1, which is able to deliver, at each start-up, a quantity or dose of detergent to the washing tank 3. This dispensing device 9 comprises a reservoir 10 capable of containing several doses of detergent, a metering chamber 13 capable of collecting a dose of detergent from or reservoir 10, and an electrically controlled valve 19, capable of controlling a first passage 16 between the metering chamber 13 and the washing tank 3. The water which circulates in the washing pipe via a nozzle 8 enters the receiving tube 17 and reaches the metering chamber 13 of the dispensing device 9 when the valve 19 is open, while it flows back into the washing tank 3 of the machine 1 via the meatus 18 when said valve 19 is closed.

Description

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  SYSTEM FOR WATER SUPPLY AND DETERGENT OF A

DISHWASHER

  The present invention relates to a system for supplying water and detergent to a dishwasher. More specifically, the invention relates to a system comprising: a water supply duct, which extends at least partially inside the machine, for supplying a wash tank with water from a water source, and a liquid detergent dispensing device, mounted in a wall of the machine, above the washing tub, and able to dispense, at each operation, a predetermined amount or dose of detergent, to The washing tub, said dispensing device comprising: a reservoir that can hold several doses of detergent, a metering chamber designed to collect a dose of detergent from the reservoir, and an electrically operated valve to control the

  passage between the dosing chamber and the washing tub.

  The detergent dispensing device can be mounted in a fixed side wall of the machine, or in the front wall of the machine (or the access door) of the machine.

  In the previous Italian patent application 67239-

  A / 89, on behalf of the same applicant, a device is described

  liquid detergent dispenser of the type specified herein

  above, can be mounted in the access door to La

  washing room of a dishwasher.

  In a water and detergent supply system of the type specified above, the aforesaid water supply conduit may be connected to the detergent dispensing device via a flexible tube. However, when the detergent dispenser - is mounted in the door, this tube would be solicited at each opening and closing of the door, with the risk that appear, because of aging and wear,

  cracks and leaks resulting therefrom.

  In a water and detergent supply system of the type specified above, it is furthermore appropriate that the detergent dispensing is effected by passing a flow of water (from the air duct) into the dosing chamber of the detergent dispenser. The feed to the washing tub of the machine is also carried out in this case an effective dipping or washing of the dosing chamber of the dispensing device. In addition to this requirement, it must also be borne in mind that During certain phases of the washing cycle, it is necessary to be able to supply the washing tub of the machine with water only, without

detergent distribution.

  The object of the present invention is to provide a system for the supply of water and detergent of a dishwasher of the type indicated above, which allows a simple and economical way to meet these requirements. This object is achieved according to the invention by means of a system of the type thus described, the main characteristic of which lies in the fact that the water supply pipe ends, in the washing tub, with an adjacent nozzle at said sidewall of the machine, and that said first passage of the detergent dispenser terminates with a receiving tube which extends from said sidewall of the machine to the wash tub, and which is disposed around said nozzle, defining relative to the latter, a meatus communicating with the washing tub; the arrangement being such that, during operation, the water circulating in said supply duct through said nozzle, enters the receiving tube and reaches the dosing chamber of the 3 - dispensing device, when the aforesaid valve is open and, on the contrary, flows back into the washing tub of the machine while passing through said meatus When said shutter

is closed.

  Other features and advantages of the invention

  will appear on reading the detailed description

  which follows, made with reference to the accompanying drawings, given purely by way of non-limiting example, in which: Figure 1 is a schematic illustration, in section, of a dishwasher with a water supply system and detergent according to the invention, Fig 2 is a partial schematic view of another embodiment of the system according to the invention,

  FIG. 3 is a sectional view of the door of a washing machine

  4 is a sectional view along line IV-IV of FIG. 3, and FIG. 5 is a partial sectional view, which shows part of the dispensing device of FIG. detergent from the

  Fig 4, under different washing conditions.

  In the illustrated embodiments, which will now be described, the detergent dispensing device is placed in the front access door to the washing tub of the machine This could however be

  placed in a fixed lateral part of the machine.

  Referring to Fig 1, the reference 1 indicates a dishwasher with a front door 2 access to the tub or wash chamber 3 The door 2 is pivotable about a horizontal axis bearing

reference 4.

  The machine 1 is equipped with a water supply system and detergent, comprising a water supply conduit, bearing the reference 5, along which are interposed, according to a technique known per se, a main electromagnetic valve 6 and a device

decalcifier 7.

  The tube 5 is intended (according to a known technique in

  self) to be connected to a water source, not shown.

  Inside the machine, downstream of the decalcifier 7, the tube 5 passes through the bottom wall 3a of the Washing tank 3, next to the door 2, forming an end ejection nozzle 8, facing the door. Inside the door 2 is placed a liquid detergent dispensing device carrying the reference 9 as a whole. This device comprises a reservoir 10 having a filling orifice 11 which extends through an opening provided in the surface of the door 2 facing the washing tub, and to which is coupled a sealed movable closure cover The reservoir 10 is able to communicate with a metering chamber 13, through a passage 14, on which is interposed a valve 15, normally open The volume of the chamber 13 corresponds to the quantity or predetermined dose to be poured each time to the washing chamber The metering chamber 13 is capable of communicating with the washing tub 3 via a duct 16 which extends towards said washing tank through the inner surface of the door 2 The portion of the tube 16 projecting towards the washing tub 3 is constituted by a t This receiver tube, when the door is closed, couples with the nozzle 8 described above. As shown in FIG. 3, when the door is closed, the diverging end portion of the receiving tube 17 laces around the end of the nozzle 8, defining with respect thereto a channel 18 communicating with the washing tub 3 A valve 19, normally closed, controls the communication between the tube 16 and the metering chamber 13. In the embodiment according to FIG. 1, between the metering chamber 13 and the washing tank 3 is provided another conduit 20. The communication between the metering chamber 13 and the washing vat 3 via the duct, is carried out by means of another valve 21, -

  normally closed, electrically controlled.

  Between the arch wall of the metering chamber 13 and the reservoir 10 extends a tube 22, the length of which is interposed a nonreturn valve 23 comprising a seat 24 and a float shutter member 25. The tube 22 s' extends into the reservoir 10, and terminates near the upper edge of the orifice of

filling 11 of said tank.

  During operation, when the valve 15 is open, and the valves 19 and 21 are closed, the liquid detergent from the tank 10, goes down in

  the metering chamber 13, and fills gradually.

  The air above the detergent in the metering chamber 13 flows from this chamber through

  through the non-return valve 23 and the tube 22.

  When the metering chamber 13 is completely filled with detergent, the float 25 closes the valve seat 24, interrupting the communication between the metering chamber

  13 and the inner zone of the tank 10.

  When, subsequently, during the washing cycle, the detergent dose accumulated in the chamber 13 must be admitted into the washing tank, the control unit of the machine, according to a technique known per se, determines the contribution a flow of water under pressure through the conduit 5 to the ejection nozzle 8 At the same time, the valve 15 closes, while the valves 19 and 21 open. The water leaving the nozzle 8 enters the receiving tube 17, and via the conduit 16 and the valve 19, joins the metering chamber 13, in which it mixes with the detergent that has accumulated therein. The water and the detergent flow to the

  washing tank 3, through the valve 21 and the tube 20.

  The distribution of detergent is therefore accompanied by an energetic and effective action of washing the chamber of

  dosage 13 of the dispensing device.

  It should be noted that when the water flows into the metering chamber 13, the valve 23 prevents the passage of water from the metering chamber 13 to the reservoir, thereby detecting that the detergent contained in the

reservoir is diluted.

  When during the wash cycle, it is appropriate that the tank 3 is fed only water, so without dispensing detergent, the valve 19 is kept closed: the water, through the conduit 5 and the nozzle 8 is then admitted into the receiver tube 17 flows back to the wash tank through the passage 18

  existing between said receiving tube and the nozzle 8.

  In the system according to the invention, because of the coupling of the supply duct 5 with the dispensing device 9, via the nozzle 8 and the associated receiver 17, it is possible to transmit the water to the washing tub 3 selectively, with or without detergent dispensing,

  simply by the control of the valve 19.

  Referring to FIG. 1, the zone at the top of the reservoir 10 communicates with an exhaust tube 26, which extends inside the door 2 above said reservoir. This tube facilitates the removal of air from the tank. outside the tank 10 when it is periodically reloaded with detergent Because the filling operation of the tank 10 is carried out with the door 2 open, that is to say approximately horizontally, it is appropriate that the tube 26 is shaped so that, when filling the tank, its end is at a level higher than the level of the orifice 11 of the tank, in order to avoid the

overflow of the detergent.

  It should further be that the tube 26 is profiled such that it has at least one portion 26a extending in a direction having a component parallel to the hinge axis 4 of the door, and at least a portion 26b extending in a direction having at least one component in a horizontal direction

  orthogonal to the previous one.

  This conformation, because of the connection curves between the tube portions defined above, makes it possible to avoid the overflowing of the detergent outside the tank 10 when the dishwasher 1 is moved from its working position and (by example in the transport phase) when it is inclined, even in an accentuated way with respect to the vertical, or even more if it is

  lying or leaning on one of the side walls.

  In the variant embodiment illustrated in FIG. 2, in place of the tube 26 there is provided a nonreturn valve 27, able to prevent leakage of the liquid from the tank, but allowing the escape of the air during the phase filling said tank, and the admission of air into the tank as the level of detergent decreases during use

gradually in this tank.

  As will be seen in more detail in the following, referring to FIGS. 3 to 5, the valves 15, 19 and 21 of the system according to FIG. 1 can easily be actuated by means of a single operating device. Moreover, the float check valve 23 can advantageously be made inside the tank 10. Finally, the mouth of the discharge tube 20 of the detergent dispensing device is advantageously made around or c Cte the end of the tube 16, so as to require only one opening to

  through the inner wall of the door 2 of the machine.

  The variant embodiment illustrated in FIG. 2, in addition to the aspects already mentioned above, differs from that illustrated in FIG. 1, essentially because between the metering chamber 13 of the dispensing device and the washing tub 3 is disposed a discharge tube 120, with an upwardly directed upward portion, which reaches a level higher than the top of the tank 10, and a descending portion, which ultimately opens into the wash tub along the tube 120 is not placed any valve, but siphon conformation returned from this tube is sufficient in itself to prevent the detergent contained in the metering chamber 13 can flow to the wash tank when the valve 19 is closed It is interesting that the end of the tube 120 protruding from the door 2 is, when the door is open, at a level higher than that of the metering chamber 13, in this case also to avoid possible

overflowing detergent.

  When the valve 19 is open and through the conduit 5, the nozzle 8, the receiver tube 17 and the tube 16, water under pressure is admitted into the metering chamber 13, the water and the detergent contained in this metering chamber back into the tube 120 and reach the washing tub 3,

  exceeding the bent curve at the top of said tube.

  Figs 3 to 5 relate to a detailed structural realization of a system according to the simplified diagram of Fig 1. Therefore, in Figs 3 to 5, the parts and elements similar or equivalent to elements already described, have been newly awarded

the same reference numbers.

  As can be seen in particular in FIGS. 4 and 5, in the illustrated embodiment, the void wall of the metering chamber 13 is constituted by a member 113 that slides axially in a leaktight manner as a piston in said chamber, depending on the position in which the piston member 113 is located, the volume of the chamber 13 varies, as well as the quantity or dose

  of detergent dispensed each time.

  The position of the arch wall 113 of the metering chamber 13 can be modified by manually acting on a pivoting member 114 (FIG. 3), which passes through the orifice 11 of the reservoir 10, and is accessible after removal of the cover 12. pivoting member 114 is eccentrically articulated the end of an arm or crank 116, the other end of which is articulated to an appendage 117 (FIG 4) at the top of the member 113 which defines the wall of

vo Ote of the dosing chamber.

  In the embodiment illustrated in FIGS. 3 to 5, the float check valve 23 is formed inside a median hollow portion 118 (FIG. 4) of the aforesaid piston member 113 in the bottom wall of FIG. the chamber defined inside the portion 118 of said member, is provided an opening 119 able to allow the passage of air to the exhaust tube 22, and the rise of the liquid detergent to the float 25. As this 4 and 5, the valves 15, 19 and 21 comprise respective shutters 151, 191 and 211, mounted so as to slide on three appendages or steles of a member 120 that can be moved inside the metering chamber 13 To this member 120 is hinged one end of a rocker 130, with its fulcrum 121, the other end of said beam being controlled by an operating device 140 to electrically controlled This setting device in operation can e be of the solenoid type and movable core, or of the movable piston type due to the thermal expansion of a material (for example wax) caused by the effect of the

  warming, for example by means of resistance.

  In the latter case, since the devices for operation with expansion are inherently slower than those with Soold and mobile core, it is advisable to use means of known techniques in themselves to ensure that during the switching, it firstly obtains the closure of the valve 15 (normally open), then the opening of the

  valves 19 and 21 (normally closed).

  In FIG. 4, the dispensing device is shown in the position it occupies during the filling phase of a dose of detergent in the metering chamber 13; the operating device 140 no longer functions, and through the rocker 130, it keeps the member 120 raised, so that the shutter 151 is away from the associated valve seat, while the shutters 191 and 211 (under the action of - associated thrust springs) close the seats to which

they are respectively associated.

  Fig 5 shows the dispenser in the dispensing phase of the detergent dose previously accumulated in the metering chamber 13; the operating device 140 is excited and by means of the rocker 130, keeps the member 120 lowered, whereby the valve 15 closes (pocketing the reflux of water to the tank by the

  passage 14) and the valves 19 and 21 are open.

  The liquid detergent dispensing device described above can be embodied in an integrated form with a conventional rinse aid dispenser device, with or without an associated powdered detergent dispenser, to eventually allow the user to use the choice of type detergents

liquid or powdered.

  Naturally, the principle of the invention remaining the same, the forms of implementation and the details of implementation can be greatly modified from what has been described and illustrated by way of non-limiting example, without departing of the framework of the

present invention.

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Claims (11)

  A system for supplying water and detergent to a dishwasher (1) with a washing tub (3), the system comprising: a water supply duct (5), which extends at least partially inside the machine (1) for supplying water to the washing tub (3) from a water source and a liquid detergent dispensing device (9) mounted in a side wall (2) the machine (1), able to dispense, at each operation, a predetermined amount or dose of detergent, to the washing tub (3); said dispensing device (9) comprising: a reservoir (10) capable of holding several doses of detergent, a metering chamber (13) designed to collect a dose of detergent from the reservoir (10), and an electrically operated valve ( 19) for controlling the passage (16) between the metering chamber (13) and the washing tub (3); characterized in that the water supply duct (5) terminates in the washing tub (3) by a nozzle (8) adjacent to said wall (2) of the machine, and that said passage (16 ) of the dispensing device (9) ends with a receiving tube (17) which extends from said wall (2) to the washing tub (3), and which is arranged around said nozzle (8), which defines relative therein, at least one meatus (18) opening into the washing tub (3); the arrangement being such that, during operation, the water circulating in said supply duct (5) through the nozzle (8), enters said receiving tube (17) and reaches the metering chamber (13) of the dispensing device (9), when the aforesaid valve (19) is open, and on the contrary refluxed 12 - in the washing tub (3) through said meatus (18),   when said valve (19) is closed.   2 System according to claim 1, characterized in that said detergent dispensing device (9) is mounted in a front wall of the machine, serving as a door (2) for access to the tank or chamber of washing (3).   3 System according to claim 1 or 2, characterized in that the reservoir (10) of said detergent dispensing device (9) is provided with means (26, 26a, 26b, 27) able to allow the escape of the air outside the tank, during the filling phase of this tank, the admission of air into the tank at each lowering of the level of the detergent in the tank, and able to prevent the exit of the detergent of this tank.   4 System according to claim 3, characterized in that from the top of said tank (10) part of an exhaust tube (26) with a first portion (26 a) which extends in a direction having a horizontal component parallel to the oscillation axis (4) of the door (2) and a second portion (26b) extending in a direction having a component in the direction   horizontal orthogonal to the previous one.   5. System according to claim 4, characterized in that said exhaust tube (26) is profiled so that its unloading end is at a level higher than that of the tank filling orifice (10). when the door (2) of the machine (1) is in a position suitable for allowing   filling said tank (10).   System according to one of the preceding claims,   characterized in that said detergent dispensing device further comprises a second electrically operated valve (15) capable of controlling a passage (14) between the reservoir (10) and the metering chamber (13); said second valve (15) being preferably operable together with said first valve (19) 13 - by means of the same operating device to electrical control (140).   System according to claim 6, characterized in that said detergent dispensing device (9) further comprises a third electrically operated valve (21, Fig 1), able to control a passage (20) between the dosing chamber. (13) and the washing tub (3); said third valve (21) being preferably controlled together with said first and second valves (19; 15) by means of a single device   electrically operable actuator (140).   System according to claims 2 and 6, characterized   in that in said detergent dispensing device (9) between the metering chamber (13) and the washing chamber (3) there is interposed an inverted siphon-shaped conduit (120) which, when the door is closed, extends to a level higher than that of the summit said tank (10).   System according to claim 8, characterized in that said inverted siphon-shaped duct (120) is shaped such that its emptying aperture is at a higher level than that of the metering chamber (13), when the door (2) of the machine is placed in a position suitable for filling the aforesaid tank ( 10) System according to claim 6 or 7, characterized in that said operating device is of the type to So Leno; and movable core, or movable piston type by effect of the thermal expansion of a quantity of electrically heated material.   System according to any one of the claims   characterized in that said liquid detergent dispensing device is embodied in an integrated form with a conventional rinse aid dispensing device, optionally with an associated powdered detergent dispensing device.