BACKGROUND

The invention relates to a sanitary insert unit having an insert housing, in which insert housing a valve having a valve piston is provided, which valve piston is guided in a displaceable manner in the insert housing and is movable from a rest position, under the pressure of the inflowing water, counter to the restoring force of at least one restoring element, wherein the insert unit has at least one movement damper, which damps or brakes the movement of the valve piston from the rest position into the open position.

The invention also deals with the use of such a sanitary insert unit.

Sanitary insert units are already known in various embodiments for different applications. Thus, insert units have already been created, which serve as backflow preventers in order to prevent a flow of water, which is flowing back counter to the flow-through direction and is possibly contaminated with pollutants, from passing back into the pipe network. These insert units in the form of backflow preventers have an insert housing which can be mounted between two pipe sections and in which a valve having a valve piston is provided. This valve piston is guided in a displaceable manner in the insert housing and is movable from a rest position, during which no water flows through the pipe network, under the pressure of the water flowing in following the opening of the fitting, counter to the restoring force of at least one restoring element, such that the water can flow through in the normal flow-through direction.

A sanitary insert unit of the type mentioned at the beginning is already known from DE 26 50 934 A1, said sanitary insert unit being intended to be installed in the drainage connector of a pipe disconnector, said drainage connector leading to a water consumption point, in order, in the open position of the pipe disconnector, that is to say with the piston tube thereof extended out of the drainage connector and thus with the drinking water feed pipe completely separated from the consumption point, to close the drainage connector in a liquid-tight manner, in order to prevent sanitary water that is not infrequently contaminated with added chemicals or the like and is standing in the consumption-point pipe system from flowing back or out. The previously known insert unit has, to this end, an insert housing, in which a valve having a valve piston is provided, which valve piston is guided in a displaceable manner in the insert housing and is movable from a rest position, under the pressure of the inflowing water, counter to the restoring force of at least one restoring element. In order, in spite of the fresh water flowing past the valve piston, to guide this valve piston securely without flapping and rotary vibrations, in order to damp the sliding movement of the valve piston from the rest position into the open position, a movement damper is provided, which is in the form of an outwardly leading pressure equalization and damping bore. The previously known insert unit is not intended to allow the volume of water emerging from a water outlet to build gently even when the water pipe is opened abruptly, and nor is it suitable therefor.

Many outlet fittings are in the form of single-lever fittings, in which an operating lever for opening and closing the flow of water can be pivoted and, in order to mix hot and cold water, rotated. In particular in such outlet fittings too, the problem frequently arises that the outlet fitting is opened so quickly, and possibly unintentionally, that a strong surge of water strikes the washbasin and sprays in an uncontrolled manner there and can also hit the user themselves.

SUMMARY

Therefore, the object is in particular to create a sanitary insert unit of the type mentioned at the beginning, which creates a gently building flow of water even when the water pipe is opened abruptly.

In the case of the sanitary insert unit of the type mentioned at the beginning, this object is achieved according to the invention in particular in that the at least one movement damper is configured as a hydraulic damper which has a damper housing, in which damper housing a damper piston is guided in a displaceable manner, wherein, during a sliding movement from the rest position into the open position, the damper piston displaces oil or similar viscous fluid from one side of the damper piston to the other side of the damper piston through at least one connecting duct.

The insert unit according to the invention has an insert housing, which can be mounted in the water outlet of a sanitary outlet fitting or between two pipe sections of a water pipe, for example can be inserted in a corner valve or connection valve. In this case, the insert unit is intended to create a gently building flow of water when an outlet valve provided in the water pipe is opened abruptly. To this end, a valve having a valve piston is provided in the insert housing of the insert unit, said valve piston being movable from a rest position, under the pressure of the water flowing in against the insert unit and the valve piston thereof, counter to the restoring force of at least one restoring element. In this case, the rest position can be configured as the closed position of the valve or be in the form of a flow-through position which affords a reduced flow cross section compared with the open position. The damper housing, which is arranged in the insert housing and around which the water flowing through the insert housing flows, at least in the open position, is a constituent part of a movement damper, which damps or brakes the sliding movement of the valve piston from the rest position into the open position such that the valve piston only slowly opens the flow-through of the water in the region of the insert unit and the flow of water accordingly builds only slowly even when the outlet valve is opened abruptly. To this end, according to the invention, the at least one movement damper is configured as a hydraulic damper which has a damper housing, in which damper housing a damper piston is guided in a displaceable manner, wherein, during a sliding movement from the rest position into the open position, the damper piston displaces oil or similar viscous fluid from one side of the damper piston to the other side of the damper piston through at least one connecting duct. Such a restoring unit, which has a movement damper configured as a hydraulic damper, is able to damp or brake the sliding movement of the valve piston from the rest position into the open position particularly effectively.

In this case, the at least one restoring element can for example also be in the form of a rubber-elastic restoring element. However, in a particularly simple and long-lasting embodiment according to the invention, the at least one restoring element is in the form of a restoring spring.

In this case, a simple structure and easy mounting of the insert unit according to the invention are favored further when the at least one restoring element is in the form of a compression spring.

In order that the movement damper can brake this sliding movement of the valve piston as simply as possible, it is advantageous when the valve piston is connected to the damper piston in terms of movement via a piston rod. To this end, it is expedient when the piston rod is connected to the valve piston at its first rod end oriented counter to the direction of flow, and is connected to the damper piston at its second rod end directed in the direction of flow.

In order to move the damper piston from the open position back into the rest position again and in order in the process to again be able to displace the oil or similar viscous fluid from one side of the damper piston to the other side of the damper piston through the at least one connecting duct, it is advantageous when the at least one restoring element applies pressure to that end side of the damper piston that faces away from the flow-through direction of the insert unit.

In this case, in a particularly simple embodiment according to the invention, the at least one restoring element is arranged between a closed housing bottom of the damper housing and that end side of the damper piston that faces away from the flow-through direction.

In order to be able to mount the movement damper easily, it is expedient when the damper housing has an end-side housing opening, which is closed by at least one cover in the form of an annular disk, the annular-disk opening of which has the piston rod passing through it.

Additionally or alternatively, it may be advantageous when the damper housing is sealed off from the insert housing by a plug in the form of an annular disk, the annular-disk opening of which has the piston rod passing through it.

This plug can have been introduced into the damper housing and be held in a releasable manner on the housing inner circumference of the damper housing. In addition, it is possible for the plug to be held or secured in the damper housing by the cover in the form of an annular disk.

It is advantageous when this plug provides sealing between the housing inner circumference of the damper housing and the piston rod passing through the annular-disk opening thereof, such that the damper housing, which is subdivided into two housing portions by the damper piston, is closed off tightly from the external housing interior of the insert housing.

In order to allow the volume of water flowing through per unit time to build as slowly as possible after the outlet valve has been opened, it is advantageous when, in the rest position, the valve piston of the valve butts preferably partially or with play against a circumferential rim in the insert housing, said circumferential rim being in the form of a valve seat and bounding a flow-through opening. If the valve piston of the valve butts only partially or only with play against the valve seat, a small water quantity can already flow between the valve piston and the valve seat thereof in the rest position and abrupt separation of the valve piston from the valve seat is avoided.

By contrast, the valve piston of the valve is spaced apart, in the open position thereof, from the circumferential rim, in the form of a valve seat, in the insert housing.

It is possible for the sanitary insert unit to be in the form of an unaerated jet former or of a jet aerator, which jet aerator mixes the water flowing through with ambient air during use.

If the insert unit according to the invention is in the form of a jet aerator, it is advantageous when this jet aerator has a jet splitter, which divides the water flowing through into a multiplicity of individual jets during use. Such a jet splitter can be in the form for example of a perforated plate, which has a multiplicity of flow-through holes that form individual jets.

In order that ambient air can be drawn into the housing interior of the insert housing of an insert unit in the form of a jet aerator, said ambient air subsequently being intended to be mixed therein with the water flowing through in a mixing zone, it is expedient when, in the circumferential wall of the insert housing, at least one aeration opening opens out, which is provided in an annular zone of the circumferential wall, said annular zone being arranged preferably directly beneath the jet splitter in the direction of flow. This is because the flow-through holes provided in the jet splitter constrict the flow cross section of the insert unit according to the invention in this region such that a negative pressure arises on the outflow side of the jet splitter according to Bernoulli's equation. With the aid of this negative pressure, ambient air can be drawn into the interior of the insert housing via the at least one aeration opening, said ambient air subsequently being mixed, in the mixing zone arranged on the outflow side of the jet splitter, with the individual jets formed in the jet splitter.

In order that the individual jets mixed with ambient air in the interior of the insert housing are formed into a homogeneously emerging and as far as possible non-spraying outlet jet again, it is advantageous when the jet aerator has an outflow-side flow straightener having a honeycomb, lattice or mesh structure, which honeycomb, lattice or mesh structure is formed by webs that intersect at intersecting points.

In this case, the vandalism-resistant function of the insert part according to the invention is ensured and pushing up of the flow straightener and the insert parts that follow counter to the direction of flow is avoided when the honeycomb, lattice or mesh structure of the flow straightener is integrally formed on the insert housing.

In order to be also subsequently able to additionally divide the individual jets created in the jet splitter and to mix them readily with the ambient air drawn into the insert housing, it is advantageous when, between the jet splitter and the flow straightener, at least one insert part having a lattice or mesh structure made up of webs that intersect at intersecting points is provided.

The lattice or mesh structures of the insert parts located one above another can be positioned at a fixed spacing from one another when the at least one insert part has, at least on its outer circumference, an encircling annular wall, on which annular wall the lattice or mesh structure of this insert part is integrally formed. In this case, the annular wall of each insert part is dimensioned such that the spacing of the lattice or mesh structures integrally formed on these annular walls is fixed.

In a particularly simple and easy to produce embodiment according to the invention, the damper housing is releasably connectable or integrally connected to the jet splitter.

In an advantageous embodiment according to the invention, the damper housing is held in a preferably central insertion opening of the jet splitter by a latching connection.

In order to be able to accommodate the constituent parts of a movement damper in a damper housing of sufficiently large dimensions, it is advantageous when the jet splitter and preferably also the flow straightener and optionally also the at least one insert part provided between the jet splitter and flow straightener each have an insertion opening, which insertion opening(s) has/have the damper housing passing through it/them.

In a preferred development according to the invention, during a sliding movement during use, the damper piston displaces oil or similar viscous fluid through at least one connecting duct from the rest position into the open position and through at least one return-flow duct from the open position into the rest position. In such an embodiment, the pressure stage of the movement damper for the one part and the rebound stage thereof for the other part can also easily be configured differently.

In order to be able to fasten a damper housing that is releasable from the jet splitter sufficiently firmly to the jet splitter in the use position of the insert part, it is advantageous when an insertion stop is provided on the outer circumference of the damper housing, and when the damper housing is insertable into the insertion opening in the jet splitter until the insertion stop butts against a mating stop on the jet splitter.

In order to be able to displace the oil or similar viscous fluid located in the damper housing easily from one side of the damper piston to the other side of the damper piston, it is expedient when the damper piston has, on its outer circumference, at least one circumferentially open groove, which bounds the at least one return-flow duct together with the housing inner circumference of the damper housing. In this embodiment, it is possible to dispense with small and possibly easily soiled flow-through bores or return-flow ducts in the damper piston.

It is advantageous when the at least one connecting duct has, on the inflow side, a duct inlet, which is arranged on that piston end side of the damper piston that faces the housing bottom of the damper housing.

In a preferred embodiment according to the invention, the at least one connecting duct has, on the outflow side, a duct portion which is provided preferably in a groove-like indentation between the piston rod and an inner circumferential wall, which inner circumferential wall bounds a plug-in opening in the damper piston, said plug-in opening accommodating one rod end of the piston rod.

It is advantageous when the movement damper has a pressure stage, which is active under the pressure of the inflowing water and during which the valve moves from its rest position into the open position, and a rebound stage, during which a restoring movement of the damper piston from the open position into the rest position of the valve takes place.

In order that the emerging volume of water builds sufficiently slowly when the outlet valve is opened, it is advantageous when the pressure stage of the movement damper is configured to be harder than the rebound stage.

To this end, in a preferred embodiment according to the invention, a ring seal is provided on that end side of the damper piston that faces away from the direction of flow, said ring seal closing the at least one return-flow duct during a sliding movement of the damper piston from the rest position into the open position. This ensures that, during such a sliding movement, the fluid can be displaced by the damper piston only through the at least one connecting duct and that the movement damper can easily be configured in an appropriate way in this pressure stage.

In order to prevent troublesome noises that are audible to the user during the sliding movement of the damper piston, it is advantageous when the valve piston bears a surface layer made of elastic material, at least in the annular zone butting against the valve seat in the rest position.

In order to provide the valve piston with such a surface layer made of elastic material, it is advantageous when the valve piston bears a surface layer made of elastic material on its end side facing the valve seat, said surface layer being mounted on the valve piston so as to be displaceable in a radial direction. Since, in this developing embodiment, the surface layer is mounted on the valve piston so as to be displaceable in a radial direction, the surface layer, which consists of an elastic, but incompressible material, is pressed together by the pressure of the inflowing water and displaced outwardly in a radial direction toward the valve seat, such that even briefly audible troublesome noises during the sliding movement of the valve piston from the rest position into the open position are counteracted.

In this case, the surface layer can be configured in the form of an annular disk, wherein the annular-disk opening in this surface layer has a peg, protruding from the valve piston, passing through it.

By contrast, however, it is also possible and advantageous when at least one plug-in peg is integrally formed on the flat side, facing the valve piston, of the surface layer, which plug-in peg is held in an associated peg opening in the valve piston.

Since such an elastic surface layer can result in excessive and function-imp airing sealing off of the insert part in the narrow region between the valve piston, surface layer, valve seat and an optionally upstream dome screen or filter screen, it is expedient when the circumferential rim, in the form of a valve seat, in the insert housing has at least one peripheral indentation, which indentation is water-permeable even in the rest position of the valve.

In order to prevent audible troublesome noises during the sliding movement of the valve piston, it can additionally or alternatively be advantageous when the valve piston, on its circumferential rim facing the valve seat, bears a chamfer or has a rounded piston rim. This rounded piston rim or the chamfer can be formed directly on the valve piston or its surface layer borne thereby.

The valve piston and its elastic surface layer can optionally also be produced as multi-component injection-moldings. However, in a simple embodiment according to the invention that is associated with comparatively little production outlay, the valve piston and the elastic surface layer are produced as separate components which are mounted on one another only after they have been produced. In order that the elastic surface layer is held securely and firmly on the valve piston in the mounted state, in a preferred embodiment according to the invention, the surface layer engages with its circumferential-rim region behind the valve piston and in particular behind a subregion, protruding in a flange-like manner, of the valve piston.

In order to guide the valve piston with as little frictional resistance as possible during its adjusting or sliding movement and in order to avoid undesired squeaking noises during the sliding or adjusting movement of the valve piston, it is advantageous when guide ribs are provided on the outflow side of the valve seat, said guide ribs each forming a linear piston guide for the valve piston during the sliding movement of the valve piston.

In order in this case to be able to guide the valve piston particularly well without increasing the sliding resistance, it is advantageous when the surface layer has a circumferentially protruding annular flange, and when the guide ribs impinge on this annular flange of the surface layer.

In an advantageous use of the sanitary insert unit described above, the sanitary insert unit is interposed in a corner valve or connection valve of a sanitary water pipe.

By contrast, however, in a preferred further use according to the invention of the sanitary insert unit described above, the sanitary insert unit is mounted in the water outlet of a sanitary outlet fitting. Such an insert unit can also be substituted subsequently for a commercially customary jet regulator, in that, instead of this commercially customary jet regulator, the insert unit according to the invention is now inserted into the outlet mouthpiece, which outlet mouthpiece can subsequently be mounted by way of an internal or external thread on a complementary mating thread on the water outlet of the sanitary outlet fitting.

