FR2461480A3 - Compact water supply system for domestic dish washers - has one piece plastics component containing several elements promoting clog-free water circulation - Google Patents

Abstract

The water supply mechanism has a level regulating vessel with a chamber which forms an air trap. The partition has an overflow edge and a riser as well as a compensating vessel and a siphon between the air trap chamber and the compensating vessel. The mechanism is assembled in one plastics component which can be set on the tank. The riser for the entire water supply forms a communicating tube with the tanko that the same level is set in the riser as in the tank. A downwardly aligned collecting apron is moulded into the upper part of the connecting pipe leading from the riser to the drainage trough of the tank while webs are provided in the riser beneath the overflow edge of the partition to smooth down the water column before the overflow edge. All the fresh water passes into the tank through the riser. The presence of the apron ensures that dirt particles cannot now pass from the tank to the level regulating vessel.

Description

The present invention relates to a water supply device for dishwashers which comprise, to limit the quantity of fresh water arriving in the tank, a level adjustment container delimiting a chamber of smaller volume which forms a air trap for a level switch, which has an air duct and is connected to a drain pump by a duct, the level adjustment container containing a partition with a weir edge at the level of a level determined filling of the washing tank, as well as an elevating duct which is separated from the chamber, forming an air trap, by the overflow edge, a connecting duct leading to the drain pan of the tank and communicating with the lower part of the lifting duct into which also opens a water intake duct, the duct connecting the chamber, forming the air trap, and the drainage system, extending in a curved manner above the level of summer tank water rminé by the edge-weir, and an expansion receptacle, connected to the emptying system of the drain pump, being provided after a downpipe which extends the duct leading to the siphon.

A dishwasher fitted with a device of this type is known from German patent application 2,729,746.

In this water supply device consisting of several elements connected by flexible hoses, the fresh water partly flows directly into the washing tub through a container for the supply of fresh water and partly into the container level adjustment via a bypass duct and the lifting duct.

 The object of the present invention is to provide a water supply device of the type mentioned which is simpler and more compact while reducing the fouling of the ar trap chamber so as to create a reliable and low level device. cost price.

 These problems are solved in accordance with inventi.on by a water supply device which is characterized in that the device composed of the calf adjustment container with the air trap chamber, the Daration partition and the lifting duct as well as the container valve and the siphon provided between the air trap chamber and the expansion container, is housed inside a piece of synthetic material which is attached to the washing tub, in that the lifting duct is made for the passage of the total quantity of water supplying the washing tank, in that a downward-facing retaining apron is produced in the upper zone of the duct connecting the lifting duct to the drain pan of the washing tank washing and in that bars are provided inside the lifting duct and below the overflow edge of the partition to reduce the turbulence of the water column before the overflow edge.

 The duct leading from the air trap chamber, to the expansion vessel and siphon, is closed by a closure member, a float or the like when the chamber has been emptied.

the retaining apron and the bars protrude at an acute angle in the connecting pipe and in the lifting pipe while being oriented in the direction of the stream of water flowing in the washing tank and channels at 1 ' inside the lifting duct and the siphon are free of steps thanks to transition zones.

The bars are curved downward, partially overlapping, and have no vents.

A conduit derived from the water inlet conduit to the lifting conduit opens into the expansion vessel and has hydraulic resistances, a head or the like which opposes the water column, present in the bypass conduit, a resistance more higher than that which is necessary for the suction of the water column of the siphon.

 According to another characteristic of the invention, one or more U-shaped tubular conduits, connected in series, are provided in the bypass conduit leading to the expansion vessel.

 The inlet opening of the water inlet pipe of the lifting pipe is preceded by an intermediate wall which deflects the water flow downstream of the overflow edge and the compartments of the lifting pipe, delimited by the intermediate wall , have vents.

 The riser bars can be rinsed with clean water.

For this purpose the intermediate wall has one or more openings through which the water is conducted on the bars.

 The duct connecting the lifting duct to the washing tank comprises, in addition to or in place of the retaining apron, a valve which is opened when water flows from the lifting duct to the washing tank.

The embodiment according to the invention allows the elimination of connections in flexible pipes between the various organs of the device which therefore can be made in one piece and made of synthetic material. The arrival of the fresh water stream which is directed into the washing tank by the lifting duct effectively prevents, in cooperation with the retaining apron provided in the duct connecting the lifting duct to the tank, the residues present in the tank to arrive in the level adjustment container. The retaining apron is an obstacle to the return of residues in suspension in the leveling container after emptying and during mixing of the water. The bars, provided in the area of the overflow edge of the partition, prevent the water from the vents of the level control container when the water level inside the container varies greatly, for example when the washing tub has been filled above the normal level and until a security level detector has its effect and when the circulation pump is running at the same time. Thanks to the bars, suspended particles which, despite the presence of the stop apron, have arrived inside the lifting duct, may be kept far from the weir edge and therefore cannot pass over this edge into the chamber of the air trap.

 Various other characteristics of the invention will also emerge from the detailed description which follows.

 An embodiment of the object of the invention is shown, by way of nonlimiting example, in the accompanying drawings.

 Fig. 1 shows in section the water supply device according to the invention.

 Fig. 2 is a section along the line I-I of FIG. 1.

The water supply device that can be mounted on the side wall of the washing tank of a dishwasher is made of synthetic material in the form of a single piece which has a connection pipe for the water inlet 1. The water arriving through line 1, in the direction of the arrow, first rises in the lifting line 2 and then descends to flow into the dishwasher tank passing through line 3 connecting the lifting line to the drain pan. The lifting pipe forms a tube communicating with the tank so that the water level in the lifting pipe is the same as that in the washing tank.

 In order to adjust the filling level, the lifting duct has a widening which delimits a level adjustment container and in which a side wall of the lifting duct forms a partition 4 with a weir edge 5 relative to an air trap 6 for the connection 7 of a chamber 8 delimiting a level switch.

when the water level inside the washing tank reaches the predetermined level a, the water level in the lifting duct reaches the overflow edge 5. Due to the small volume of the chamber 8, a small amount of water crossing the overflow edge is sufficient to act on the trap at ar 6 and to trigger the level switch, not shown, which controls the closing of a valve stopping the admission of water into the tank.

A conduit integrated in the synthetic material envelope of the water supply device connects by describing a curve 9 above the water level a of the tank determined by the edge # weir 5, the chamber 8 of the trap air 6 and an expansion vessel 10. Thanks to the difference in level between the curved part 9 and the expansion vessel 10, the integrated duct forms a siphon 11. The expansion vessel 10 which is delimited by a space in the envelope made of synthetic material has at its bottom a tube 12 connecting it to the emptying system of the tank connected to the emptying pump. When the washing tank is filled, the water level also increases inside the expansion vessel 10 via the tubing 12. As soon as the predetermined level is reached in the tank, the water in the inside the container 10, forming a communicating vessel, is also at level a and in chamber 8 the water reaches switching level b while the water is at level c inside a overflow 13 connecting the overflow edge 5 to the chamber 8, and at a level d inside the siphon 11. An air cushion is enclosed between the levels in the expansion vessel and in the siphon. The water level inside the expansion vessel does not reach the outlet opening of the elbow 9 from the siphon towards the expansion vessel.

During the operation of the dishwasher drain pump for a water change, the siphon takes effect and the chamber 8 is emptied as a result of the lowering of the level a inside the tank and lowering, possibly accelerated by the suction exerted by the tubing 12, the water level in the expansion container. The volume of the expansion vessel is at least equal to the volume of the quantity of water occupying the chamber 8 when the switching level b is reached.

As soon as the siphon acts, the air cushion of the latter moves towards the expansion receptacle 10, while the water present in the latter flows into the drainage system via the tube 12e from the emptying of the expansion vessel, an equal amount of water is drawn by it from the chamber 8. After the complete emptying of the chamber 8 air is sucked in via the level adjustment container and the expansion vessel empties. Due to the presence of the expansion vessel 10, the chamber 8 can be emptied even when the flow speed is low in the emptying system and the emptying is not hampered by In order to prevent the expansion vessel 10 from sucking air from the chamber 8 already emptied, by means of the siphon, it is possible to provide a valve preferably a float 14, for example before the outlet of the siphon from room 8.

 A retaining apron 15 which prevents the particles in suspension from returning back into the lifting duct 2 from the washing tank, is provided inside the duct 3 connecting the level adjustment container to the tank. In the overflow zone the water level is regulated by additional bars 16, 17 directed or curved downward and which are provided below the overflow edge inside the lifting duct. the bars 16, 17 also prevent residues1 conveyed by the water, from crossing the weir edge and entering the chamber 8. Thanks to the bars 16, 17 the water cannot, moreover, not spur out of the adjustment container level passing through the vents 18 during a forteagiteticn of this water during the operation of the circulation pump and when the washing tub has been filled to the safety level due, for example, to a lack of tightness of the inlet valve.

In order to favorably influence the flow of the water current, the channels of the water supply device have transition zones. Small diameter vents 23 are provided in the curved bars 16, 17 to prevent the formation of air cushions inside the spaces delimited by these bars.

 A secondary conduit 20 derived from the inlet conduit 1 of 11 water and leading to the expansion receptacle 10 makes it possible to rinse the latter by means of chilled water. Hydraulic resistors, for example in the form of one or more U-shaped tubular assemblies, are provided inside the secondary duct 20. When the expansion vessel 10 is emptied, the hydraulic resistors oppose the column d the water 21 has in the secondary conduit 20 a resistance greater than that which is necessary for the suction of the water column present in the siphon 11. As a result, the vacuum prevailing inside the expansion vessel 10, and necessary for the siphon to act effectively, cannot be compensated by the presence of the secondary duct 20.

 An intermediate partition 24, diverting the stream of water downwards before the overflow edge 5, is provided before the outlet opening of the water inlet duct 1 leading to the lifting duct 2. The compartments of the lifting duct, delimited by the intermediate partition, have vents 18, 25 at their upper part. When the level changes inside the washing tank and the level adjustment container following the stopping of the circulation pump, the level can rise faster in the area of the vent 25, while the level rise in the compartment - before the overflow edge 5 is delayed by the bars 16, 17, which has the effect of preventing residues suspended from crossing the weir edge 5 and arriving in the chamber 8 forming an air trap.

 In order to prevent water from flowing from the tank to the level adjustment container passing through the connecting pipe 3, this can be fitted with a valve which is open when the water flows from the riser 2 towards the tank but which is closed for water flows in the opposite direction.

 Openings 19 provided in the intermediate partition 24 make it possible to rinse the bars 16 17 by means of a stream of water derived from the main stream of fresh water.

Claims (10)

REVEKDICAXIONS  1 - Water supply device for dishwashers which comprise, to limit the quantity of fresh water arriving in the tank, a level adjustment container delimiting a chamber of smaller volume which forms an air trap for a switch of level, and which has a ventilation duct and is connected to a drain pump by a duct, the level adjustment container containing a partition with an overflow edge at the level of a determined filling level of the tank washing, as well as a lifting duct which is separated from the chamber, forming an air trap, by the overflow rim, a connecting duct leading to the tank drain pan and communicating with the lower part of the lifting duct into which opens also a water intake duct, the duct connecting the chamber, forming the air trap, and the emptying system, extending in a curved manner above the water level of the tank determined by the overflow edge , and a story pressure relief valve, connected to the emptying system of the emptying pump, being provided after a downpipe which extends the duct leading to the siphon, characterized in that the device, consisting of the level adjustment container with the chamber (8) forming an air trap (6), the partition (4) and the lifting duct (2) as well as the expansion vessel (10) and the siphon (11) provided between the chamber forming an air trap and the expansion receptacle is housed inside a plastic part which is attached to the washing tank, in that the lifting duct (2) is made for the passage of the total amount of water supplying the washing tank, in that a downward-facing retaining apron (15) is produced in the upper zone of the duct (3) connecting the lifting duct to the drain pan of the washing tank and in that bars (16, 17) are provided inside the lifting duct and below the overflow edge (5) of the partition (4) to reduce the turbulence of the water column before the weir edge.  2 - Device according to claim I, characterized in that the duct leading from the chamber (8) forming an air trap, towards the expansion vessel (10) and forming a siphon (11), is closed by a closure member, a float (14) or the like when the chamber has been drained. 3 - Device according to claim 1, characterized in that the retaining apron (15) and the bars (16, 17) protrude forming an acute angle in the connecting duct (3) and in the lifting duct (2) while being oriented in the direction of the stream of water flowing in the washing tank and in that the channels inside the elevating duct and the siphon are free of steps thanks to transition zones. 4 - Device according to one of claims î to 3, characterized in that the bars (16, 17) are curved downwards, partially overlapping. 5 - Device according to one of claims 3 and 4, characterized in that the bars (16, 17) do not include vents (23).  6 - Device according to claim 1, characterized in that a conduit (20) derived from the water inlet conduit (1) to the lifting conduit (2) opens into the expansion vessel (10) and has hydraulic resistances , a head (21) or the like which oppose, to the water column present in the bypass duct (20), a higher resistance than that which is necessary for the suction of the water column of the siphon ( 11). 7 - Device according to claim 6, characterized in that one or more U-shaped tubular conduits, connected in series, are provided in the bypass conduit (20) leading to the expansion vessel (10).  8 - Device according to one of claims 1 and 6, characterized in that the inlet opening of the water inlet pipe (1) of the lifting pipe (2) is preceded by an intermediate wall (24) which deflects the water flow downwards before the weir edge (5) and in that the compartments of the lifting duct (2) delimited by the intermediate wall (24) have vents (18, 25).  9 - Device according to one of claims 1 to 8, characterized in that the bars (16, 17) of the lifting duct (2) can be rinsed by means of fresh water. 10 - Device according to one of claims 8 and 9, characterized in that the intermediate wall (24) has one or more openings (19) through which the water is conducted on the bars (16, 17).  II - Device according to one of claims 1 to 10, characterized in that the duct (3) connecting the lifting duct (2) to the washing tank comprises in addition to or instead of the retaining apron (15) a valve which is opened when water flows from the lifting duct (2) to the washing tank.