DE69101845T2 - Automatic domestic water lifting device. - Google Patents

Description

The present invention relates to an automatic lifting device for household waste water for discharge into the sewer system.

Experience shows that in many cases it is not possible to install bathtubs, washbasins, bidets, showers and sinks in bathrooms and kitchens because the sewerage system is located at a height above that of the points to be disposed of.

From the state of the art according to DE-A-3516656 or FR-A-2151221, devices are known which comprise a container into which the waste water flows and, as soon as the water level reaches a sufficient height, a float switch controls the switching on and, conversely, the switching off of a submersible pump.

This device has several disadvantages, namely:

- The need to position the above-mentioned container below the drain to be emptied. This is possible for washbasins and sinks, but impossible for anything that is placed directly on the floor, such as bathtubs, bidets and showers, where it is then necessary to position them higher to prevent the liquid inside from reaching an excessive height before the drain is triggered, which in any case stops before complete emptying has taken place, depending on the length of the lever arm of the float.

- The well-known phenomenon of "hitting" which is caused by the pump sucking too quickly in relation to the amount of waste water entering the tank, causing a discharge in bursts (switching on-switching off-switching on-switching off...), which is also very damaging and dangerous for the electric motor.

The device according to the invention, in contrast, allows to achieve a continuous, regular suction.

It is miniaturized so that it can be installed at very low heights and therefore in any case not higher than the usual height of the bottom of the lowest container, for example a shower tray, in order to obtain the required gradient.

For the description, it is useful to refer to the drawing, attached purely as a non-limiting example, in which Figure 1 exclusively represents the lifting device according to the invention and Figure 2 represents a view of the same device mounted on a shower drain.

In these drawings, in which the same elements are indicated by the same reference numerals, the body 1 of the lifting device comprises the feed pipe 2 for the waste water to be pumped out, which is connected to the container R to be emptied (in this example a shower tray). This pipe, which enters the body 1 from below, is bent upwards to a peak 3 in the form of a pronounced bend. The cross-section of the area 2 of the pipe decreases sharply to the peak 3, from which the section 4 of the pipe, with a much larger cross-section, slopes to end at the body of a conventional suction pump 5 enclosed in the body 1. Immediately in front of the peak 3, a miniature float 6 is mounted on a very short lever arm 7. Reference symbol P designates an air inlet.

The device works as follows: the waste water arrives from bottom to top, as indicated by the arrow, and acts on the float 6, which then activates an electrical contact that causes the suction pump 5 to switch on. The important narrowing of the pipe 2 immediately before the peak 3 causes a throttling that creates a Venturi effect which, combined with the suction effect of the pump 5, causes a rapid, absolutely complete emptying through the pipe 8, even when there is only a very small flow. The float 6 then returns to its rest position, which also causes the pump 5 to switch off by breaking the electrical circuit, until a new working cycle.

The aforesaid beating is avoided by the fact that, as a result of the suction by the pump in the greatly reduced space of the device, this affects the liquid level, which begins to rise by forced displacement due to the inclination 2'.

From the above description it is clear that this easily installed device ensures rapid and complete suction of the waste water.

It is clear that the attached drawing is schematic, all shapes and proportions can be given to the components without departing from the essence of the invention, which is determined by the content of the claim.

Claims (1)

1. Automatic lifting device (1) for domestic waste water, intended for connection to a drain and comprising a suction pump (5) controlled automatically according to the level of the liquid to be drained, characterized in that it has, at the bottom, an upwardly directed channel (2) for the supply of water to be drained, with a cross-section that decreases significantly up to a bend (3) forming the top, followed by a channel (4) with a steep incline and a larger cross-section that opens into the body of the suction pump (5), and a miniature float (6) arranged immediately before said bend (3) at the narrowest point for controlling an electrical contact that determines the activation of said suction pump (5) when the level required for emptying is reached, said decreasing cross-section determining a Venturi effect that, together with the suction by the operating pump, creates a completely complete emptying is ensured, even with a very small amount, for example from a hand shower that is barely turned on, after which the miniature float (6) returns to the rest position and switches off the suction pump until a new working cycle.