This invention relates to a device for improving detergent feed into the tub of a washing machine, washing-drying machine or the like of the type comprising a tray or drawer for containing the detergent, with a pipe connecting said tray to the tub in which a rotary drum is positioned containing the clothes to be treated. During clothes washing, it is necessary to prevent steam passing from the tub into the pipe connected to it, and then through this to the tray containing the detergent. This could lead to moisture absorption by the detergent, with consequent difficulty in feeding it into the tub when required.
To prevent this, it is known to provide elbow-shaped pipes comprising a U trap filled with water in which the steam originating from the tub disperses without reaching the detergent tray. CH-A-368 772 discloses a device comprising a U trap, in which the tray has two compartments and is provided with a flexible longitudinal element, upstream the U trap, for preventing the water/foam from entering one of the compartments when the other is emptyed. Although this arrangement solves the aforesaid problem, it has the main drawback of retaining detergent within the U trap when fed to the tub.
The detergent placed by the user in the corresponding tray is therefore only partly used during clothes washing. The wash quality therefore also suffers to a greater or lesser extent by the deficiency represented by the detergent quantity remaining in the U trap, with the result that the clothes may not be perfectly washed.
In addition, this deposition of detergent in the U trap can, if the machine remains unused for a long period, block the pipe connecting the detergent tray to the tub in which the drum containing the clothes rotates. This means that the washing machine cannot be used and has to be serviced at some cost.
An object of the present invention is to provide a device of the stated type which allows improved feed of detergent from the tray to the tub in which the clothes are washed.
A further and no less important object is to provide a device for preventing steam transfer from the tub to the detergent tray which is of simple and low-cost construction.
A further object is to provide a device of the stated type which allows reliable use of the washing machine or the like even after a long period of non-use.
These and further objects which will be apparent to the expert of the art are attained by a device of the aforesaid type, characterised by comprising at least one movable interceptor element transversely positioned at any point of the pipe connecting the detergent tray to the tub containing the clothes to be treated, said interceptor element being arranged to assume at least two working positions, in a first position it closing said pipe so as not to allow the usual steam present in the tub during clothes washing to reach said tray, and in a second position it freeing at least a part of said pipe to enable the detergent to pass from said tray to said tub.
The present invention will be more apparent from the accompanying drawing, which is provided by way of non-limiting example and in which:
With reference to Figures 1 and 2, a washing machine comprises a tub 1 in which a usual drum (not shown) containing the clothes to be washed rotates, the tub containing water 2 above which there is a region 3 in which steam is present during the use of said machine.
The tub comprises a projection 5 sealedly joined in known manner to a usual pipe 6 connected to a known detergent tray 7. The connection between the pipe 6 and tray 7 is made via a portion 8 inserted into said pipe. This pipe enables the detergent (not represented but indicated by the arrows F in Figure 2) to be transferred in known manner from the tray 7 to the tub 1, said detergent penetrating into this latter through a loading mouth 10. At this mouth there is provided a interceptor element 12 in the form of a body 13 connected at one end 14 to a portion 15 of the tub. For this purpose the end 14 comprises a hole 14A through which a locking element 16 can be deformably inserted, it consisting of two elastically approachable portions 17, 18 situated a short distance apart and separated by a slot 19. Each portion 17, 18 has a curved outer surface enabling the element 16 to be inserted through the hole 14A in the end 14.
When the interceptor element 12 is in its working position, its free end 20 rests against a tub projection 22 positioned at the loading mouth 10.
This working position is that shown in Figure 1. By this means, during those periods in the use of the washing machine when detergent is not being fed into the tub 1, the steam present in it is unable to rise along the pipe 6 and reach the tray 7, so wetting the detergent and causing it to partially adhere to the walls of the tray (so making it impossible for the detergent to be totally removed and fed into the tub when required according to a usual machine wash programme).
When required, water is fed in known manner into the tray 7 to remove therefrom the detergent, which penetrates into the pipe 6. This detergent reaches the loading mouth 10 where it acts (together with the water which entrains it in the direction of the arrows F of Figure 2) on the element 12. This latter rotates about its end 14 to open the loading mouth 10. This is made possible by the intrinsic elasticity of the element 12, which is preferably constructed of natural or synthetic rubber or plastics material.
Following the movement of the element 12, the detergent and its entraining water can enter the tub 1 and reach the water 2 contained therein.
In the illustrated example, the element 12, defined by a movable diaphragm or vane, is positioned at the mouth 10. The element can however be positioned at any point of the pipe 6, for example at the tray 7. In the described embodiment it must always have one end fixed to the pipe (or to another static part such as the portion 8 of the tray) so that the force of the water entraining the detergent fed to the tub 1 rotates it about this fixed end (which therefore acts as a hinge).
In the embodiment of Figure 3 (in which parts corresponding to those of the already described figures are indicated by the same reference numerals), the interceptor element 12 is of "guillotine" form and intercepts the pipe 6 by moving perpendicular to its axis W.
In this embodiment the element 12 is connected at its end 14 to a rack 30 cooperating with a gear wheel 31 driven (to rotate about its axis) by a usual electric motor, such as a stepping motor 33. The element 12 moves sealedly within a seat 35 (defined by a through hole) provided in the pipe 6 and has its free end 20 cooperating with a seat 36 opposite said seat 35. Annular steps 38 are provided within the pipe 6 at each seat to increase the seal against the pipe at said seats.
Again in the case of the device shown in Figure 3, the element 12 is arranged to assume at least two working positions. In a first position (as shown), the element 12 intercepts the pipe 6 and prevents steam from the tub 2 reaching the tray 7. In another position into which the element 12 is moved, the pipe 6 is freed so that the detergent together with its transporting water pass from the tray 7 to the tub 1.
To move the element 12, the motor 33 is operated so as to rotate the gear wheel 31. This latter, pivoted in known manner on a part of the usual washing machine cabinet, acts on the rack 30 to raise (with respect to Figure 3) the element 12 so as to free the pipe 6. Preferably, the operation of the motor 33 is controlled (in known manner) by the usual washing machine programmer or timer 50, which also controls the water feed into the tray 7. In this manner, this feed and the movement of the element 12 can be coordinated so that the movement occurs preferably before the water is fed into the tray 7.
Different embodiments of the invention have been described. Other embodiments are however possible (such as one in which the element 12 is of vane formation and is associated with a part of the pipe 6 between the tray 7 and the tub 1), these to be considered as falling within the scope of the present document.