DE29602227U1 - Drain valve for a cistern - Google Patents

Abstract

Outlet valve in which the side wall (3) has a venting opening (10) arranged at a distance from the cover wall (8) determined by the volume of air. An apron (11) is fitted below the venting opening on the side wall. The venting opening is so dimensioned that after a large flushing action the air in the float (7) can escape during the period of filling-up to the venting opening (10). With a short time closure of the outlet valve during a small flushing action no air escapes via the venting opening.

Description

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Geberit Technik AG Of-8645 Jona

Drain valve for a cistern

The invention relates to a drain valve for a cistern, in particular a toilet cistern, with a housing to be fastened to the cistern base, in which a float with an air chamber open at the bottom is arranged, which float is attached to a closing element that can be lifted in the housing and has an upper top wall and a side wall.

Drain valves of this type have been known for a long time. In these, the buoyancy of the float after a flush is triggered is ensured by the air present in an air chamber of the float. Such drain valves can be designed in such a way that premature interruption of the flush

is possible. Drain valves are also known that allow a so-called two-stage flush. When a button is pressed, the cistern is automatically emptied completely. When another button is pressed, only a portion of the amount of flush water in the cistern, for example 6 liters, is also automatically released. Practice has shown that such a two-stage flush with precisely set flush water quantities is superior to a flush interruption that the user can determine himself. With the two-stage flush, optimal savings in flush water are possible when the small amount of flush water is always exactly the same for small flushes.

The inventor has now determined through extensive research that during small flushes, when using the same type of drain valve, air can escape from the float and water can enter the float from below. As a result, the buoyancy of the float and therefore the amount of flushing water can change uncontrollably. The result of this is that either too much or too little water is released during small flushes. The inventor has now set himself the task of creating a drain valve of the type mentioned that works more precisely during small flushes and yet is not significantly more complex and expensive to manufacture.

The task is solved in a generic drain valve by the fact that the side wall of the air chamber is at a distance from the ceiling determined by the volume of air.

wall has at least one vent opening. The solution is surprisingly simple and yet functionally reliable. With the drain valve according to the invention, the float is filled with water from below up to the vent opening after each flush. The level of the water in the float and thus the volume of the air chamber is therefore always precisely determined. Accordingly, the buoyancy of the float is always the same. The vent opening can be created, for example, by means of a small hole, which does not incur any significant costs. The layer of water in the float below the vent opening prevents air from escaping from the float during a small flush.

Further advantageous features emerge from the dependent claims, the following description and the drawing.

An embodiment of the invention is explained in more detail using the single figure, which shows a schematic section through a drain valve according to the invention.

The drain valve 5 shown is detachably attached in a known manner in a cistern 1 above a drain opening 3 on the cistern base 2. A valve tube 4 with a float 7 fixedly attached to it is mounted in a valve housing 6 so that it can be lifted. In the resting state shown, the opening 3 is closed by a valve plate 13 of the valve tube 4.

closed. If the valve tube 4 is raised by means of a known actuating device 14, the drain opening 3 is opened and flushing water 17 can flow through window 19 of the housing 6 through the opening 3 into a toilet bowl (not shown here). The valve tube 4 is kept floating by the buoyancy of an air chamber 16 in the housing 6 until the desired amount of flushing water has been released.

In order to trigger a small amount of flush water, a closing weight 15 is arranged on the valve pipe 4 in a known manner, which puts a load on the valve pipe 4 during a small flush and brings it into the closed position prematurely. During such a small flush, the water level A of the completely filled cistern is lowered to level B. After a small flush, a residual amount of water of, for example, 3 liters remains in the cistern. During a large flush, the valve pipe 4 is not loaded by the closing weight 15 and thus remains raised until the cistern 1 is completely emptied.

The float 7 has the shape of an inverted cup and has a top wall 8 and an approximately cylindrical side wall 9. In the lower area of the side wall 9, one or more vent openings 10 are arranged at a certain distance from the top wall 8. These openings 10 are comparatively small and preferably have a diameter of a few millimeters, for example 2 mm. The openings 10 can also have narrow

slots or have other shapes. As the drawing shows, the float 7 has a cylindrical skirt 11 below the vent openings 10. This extends to the lower edge 12, which defines the lower opening of the float 7.

In the resting position, there is a quantity of water 18 in the float 7, the level C of which is determined by the vent openings 10. This skirt 11 is dimensioned in such a way that no air can be sucked out of the chamber 16 of the float 7 during a small flush. The height of the skirt 11 is, for example, 2 cm. Exact values can easily be determined in practical tests.

The vent openings 10 are dimensioned in such a way that no air can escape from them if they are closed briefly during a small flush. This is guaranteed with a bore with a diameter of, for example, 2 to 5 mm. The vent openings 10 must be at least large enough that after a large flush the air in the area of the skirt 11 can escape through these openings 10 and thus the water 18 can penetrate into the float 7 from below.

Claims (7)

Expectations 1. Drain valve for a cistern, in particular a toilet cistern (1), with a housing (6) to be fastened to the cistern base (2) in which a float (7) with an air chamber (16) open at the bottom is arranged, which float (7) is attached to a closing element (4) which is mounted in the housing (6) so that it can be lifted and has an upper ceiling wall (8) and a side wall (9), characterized in that the side wall (9) has at least one vent opening (10) at a distance from the ceiling wall (8) determined by the volume of air. 2. Drain valve according to claim 1, characterized in that an apron (11) is arranged below the vent opening (10) on the side wall (9). t ft * t 1 9 * · * 3. Drain valve according to claim 1 or 2, characterized in that the vent opening (10) is dimensioned so that after a large flush, the air in the float (7) can escape essentially during the period of refilling the cistern (1) up to this opening (10). 4. Drain valve according to one of claims 1 to 3, characterized in that the vent opening (10) is dimensioned such that when the drain valve (5) is briefly closed during a small flush, essentially no air can escape from this opening (10). 5. Drain valve according to one of claims 1 to 3, characterized in that it has means (15) for automatically interrupting flushing. 6. Drain valve according to one of claims 1 to 5, characterized in that the float (7) is cup-shaped. 7. Drain valve according to one of claims 1 to 6, characterized in that the ventilation openings (10) are realized by several comparatively small bores.