DE102020122850A1 - Check valve with integrated pressure relief valve - Google Patents

Abstract

The invention relates to a non-return valve (1) with a valve body (3) which (3) is in contact with the water flowing in the direction of flow (Pfl) from a closed position, in which closed position the valve body (3) lies tightly against a first valve seat (4), can be moved against a restoring force into an open position, in which the valve body (3) is lifted off the first valve seat (4), and with a pressure relief valve (5) which (5) has a closing body (6) which (6) passes through the pressure of the water flowing back against the flow direction (Pfl) from a closed position, in which the closing body (6) lies tightly against a second valve seat (7), against a restoring force into an open position, in which open position the closing body (6) from the second valve seat (7) is lifted, is movable, the restoring force acting on the closing body (6) of the pressure relief valve (5) being greater than the restoring force acting on the valve body (3). The non-return valve according to the invention is characterized in that the closing body (6) of the pressure relief valve (5) has a closing body core (8) made of a first material, which closing body core (8) has a skin at least in its partial area which lies tightly against the second valve seat (7) in the closed position or carries a layer (9) made of a second material that is softer and/or elastic in comparison

Description

The invention relates to a non-return valve with a valve body which can be moved by the water flowing in the direction of flow from a closed position, in which closed position the valve body lies tightly against a first valve seat, against a restoring force into an open position, in which the valve body is lifted off the first valve seat and with a pressure relief valve, which has a closing body, which, due to the pressure of the water flowing back against the direction of flow, moves from a closed position, in which the closing body is in tight contact with a second valve seat, against a restoring force into an open position, in which open position the closing body moves from the second valve seat is lifted, is movable, wherein the restoring force acting on the closing body of the pressure relief valve is greater in comparison to the restoring force acting on the valve body.

In the case of sanitary fittings, especially those that have a temperature thermostat and a quantity control and shut-off valve arranged separately from it, backflow preventers are regularly used in the supply lines of the cold and hot water inlets, which are intended to prevent overflow between the cold and hot water connections when the water extraction is closed. The problem arises here that when the non-return valves are closed and the water withdrawal is closed at the same time, a water volume results within the fitting that is closed off by the non-return valve and the closed quantity control valve, due to which heating and expansion, for example if the cold water inlet is briefly opened when the fitting is already warm, due to the incompressibility of the water, set considerable pressures.

In order to avoid such problems, a non-return valve intended for sanitary water fittings has been created, which has a valve body which, against a restoring force, moves from a closed position, in which closed position the valve body is in close contact with a valve seat, into an open position by the water flowing in the usual direction of flow can be moved, in which the valve body is lifted off the valve seat (cf. EP 0 653 033 B1 ). A pressure relief valve is integrated in the valve body of the previously known check valve. For this purpose, the valve body of the check valve is composed of a cone, which has a tubular extension with a lateral inlet opening, and a cone cap, which has a hood-shaped attachment with a lateral outlet opening. The closing body of the pressure relief valve is prestressed in the sealing seat between the head of the hood-shaped attachment and the upper end of the tubular extension, which serves as the valve seat of the pressure relief valve. The closing body of the pressure relief valve is designed as an elastic molded part. If the previously known non-return valve is installed, for example, in the cold water supply line of a single-lever mixer tap, in which the cold water side is shut off, but the hot water side is open, and the cold water non-return valve is closed, it can be closed by heating the water between the closed cold water valve of the fitting and the closed cold water non-return valve come to a high pressure, which acts through the opening in the tubular extension on the integrated pressure relief valve, so that the closing body is lifted from the valve seat of the pressure relief valve and the water can escape through the lateral outlet opening of the hood-shaped attachment.

A non-return valve of the type mentioned at the outset has also been created, in which the pressure relief valve has a closing body which is guided in the valve body of the non-return valve so as to be displaceable and which, in the event of excessive overpressure on the outflow side of the non-return valve, moves against the usual flow direction from a closed position against the force of a strong return spring into a Open position is movable and allows pressure relief in the supply line. The closing body of the pressure relief valve integrated into the previously known check valve is formed from a metal ball, which is pressed by the return spring against the valve seat of the pressure relief valve, which is made of thermoplastic material (cf. https://de.www.additively.com/de/showcase /en/optimized-ball-check-valve-for-liquid-filling-system-np). Since the injection molding tools used to produce the previously known check valve are subject to wear during the manufacturing process, the tightness of the previously known check valve in the area of its pressure relief valve can increasingly decrease or the functional reliability of the pressure relief valve can also be impaired.

There is therefore the task of creating a check valve of the type mentioned which is insensitive to production-related tolerances in its components and is always characterized by high tightness and functional reliability with regard to the tolerance range of the opening pressure over the entire service life.

The solution to this problem according to the invention consists in the non-return valve of the type mentioned in particular in that the closing body of the pressure relief valve has a closing body core made of a first material, which closing body core lies tightly against the second valve seat in its closed position wears a skin or a layer of a second material that is softer and/or more elastic.

The check valve according to the invention has a valve body which can be moved by the water flowing in in the direction of flow from a closed position, in which the closed position of the valve body is in close contact with a first valve seat, towards an open position, in which the valve body is lifted off the first valve seat. Since the valve body is moved from its closed position into an open position by the water flowing in the usual direction, the water flowing in the usual flow direction can pass through the check valve.

Since a backflow flowing counter to the usual direction of flow presses the valve body against the first valve seat, such backflows are effectively prevented. If the pressure on the outflow side of the check valve exceeds a specified maximum value and there is a risk of pressure-related destruction of the components located in the fitting, for example, a pressure relief valve integrated in the check valve according to the invention comes into operation. This pressure relief valve has a closing body which is lifted by the pressure of the water flowing back counter to the direction of flow from a closed position, in which the closing body lies tightly against a second valve seat, against a restoring force into an open position, into which open position the closing body of the pressure relief valve moves from the second valve seat is lifted. The restoring force acting on the closing body of the pressure relief valve is greater than the restoring force acting on the valve body, so that the non-return valve counteracts the reverse flows flowing against the usual direction of flow, while if the pressure of these reverse flows is excessive, the pressure relief valve opens slightly and the on the outflow side of the valve body of the check valve pending overpressure sufficiently reduces.

It can be advantageous if the skin or layer carried by the core of the closing body is made of an elastomer, preferably rubber, silicone or a thermoplastic elastomer.

The simple manufacture of the non-return valve according to the invention is significantly enhanced if the closing body of the pressure relief valve is designed as a two-component or multi-component plastic injection molded part.

In order for the valve body of the check valve or the closing body of the pressure relief valve to be pressed securely against the first or second valve seat in their closed position, it is advantageous if the restoring force acting on the valve body and/or the restoring force acting on the closing body are compensated by at least one rubber or resilient restoring element is applied.

A particularly simple yet functionally reliable embodiment according to the invention provides that the at least one restoring element is designed as a compression spring.

In order to facilitate assembly of the check valve according to the invention and to prevent assembly of the check valve according to the invention that would impair its function, it is advantageous if the check valve has a valve housing and if the pressure relief valve is integrated into the check valve.

A particularly compact and space-saving embodiment according to the invention provides that the pressure relief valve is integrated into the valve body of the check valve.

A development according to the invention provides that the valve body of the non-return valve is penetrated by a particularly centrally arranged overpressure channel, in which overpressure channel the closing body of the overpressure valve is movably arranged between the closed position and the open position of the overpressure valve.

In order to increase the functional reliability of the pressure relief valve integrated in the non-return valve according to the invention, it is advantageous if the second valve seat is formed by an annular surface which preferably widens conically counter to the direction of flow.

So that the closing body of the pressure relief valve only comes into contact with the annular surface of the second valve seat in a linear circumferential partial area in the closed position, it is advantageous if the closing body has a ball- or spherical segment shape. In order to safely guide the closing body of the pressure relief valve during the sliding movements in the pressure relief channel, it is advantageous if the closing body has a pin on its inflow side and/or on its outflow side, with the inflow side of the closing body being the end face in the flow direction of the pressure relief valve and the outflow side being the end face the opposite end face of the closing body is opposite.

The assembly of the non-return valve according to the invention, also in the area of its overpressure valve, is facilitated if the pin arranged on the closing body on the inflow side and oriented in the direction of flow has a cylindrical pin shape.

In order to counteract tilting of an elongate closing body in the overpressure channel, it is advantageous if the pin arranged on the outflow side of the closing body and oriented counter to the flow direction tapers towards its free pin end and is preferably designed in the shape of a truncated cone.

Jamming of the closing body on the second valve seat is counteracted if the closing body core has a diameter that is larger than the smallest diameter of the valve seat.

Preferred embodiments according to the invention provide that the closing body core is made of a thermoplastic, in particular a POM plastic or a PBT (polybutylene terephthalate) plastic. Such a closing body core made from a hard thermoplastic has sufficient stability.

It is advantageous if the elastic skin or layer consists of silicone.

The skin or layer can have a layer thickness of 0.10 to 0.50 mm, preferably 0.15 to 0.32 mm and in particular 0.15 to 0.22 mm.

It is advantageous if the skin or layer has a Shore hardness of 30° to 100° Sh-A, preferably 70° to 90° Sh-A.

A further embodiment according to the invention provides that the check valve is made of a hard material and/or a hard or hard-elastic thermoplastic material in the area of its valve seat.

Further developments according to the invention result from the claims in connection with the drawing and the description. The invention is described in more detail below using a preferred exemplary embodiment.

• 1 ein in eine sanitäre Wasserleitung eingesetztes Rückschlagventil, in das ein Überdruckventil integriert ist,
• 2 das Rückschlagventil aus 1 in einem Längsschnitt, wobei den Ventilkörper des Rückschlagventiles ein Überdruckkanal durchsetzt, in welchem Überdruckkanal der Schließkörper eines Überdruckventils von einer Schließstellung gegen eine Rückstellkraft in eine Offenstellung bewegbar ist, und wobei der Ventilkörper des Rückschlagventiles sich in seiner Offenstellung befindet,
• 3 das Rückschlagventil aus den 1 und 2 mit seinem an einem ersten Ventilsitz anliegenden Ventilkörper, wobei sich hier auch das in den Ventilkörper integrierte Überdruckventil in seiner Schließposition befindet,
• 4 den vereinzelt in einem Längsschnitt dargestellten Ventilkörper des in den 1 bis 3 gezeigten Rückschlagventiles mit dem darin integrierten und hier in seiner Schließposition befindlichen Überdruckventil,
• 5 das hier ebenfalls längsgeschnitten dargestellte Rückschlagventil aus den 1 bis 3 in der Schließstellung seines Ventilkörpers, wobei sich das in den Ventilkörper integrierte Überdruckventil hier in seiner Offenposition befindet,
• 6 den Ventilkörper des in den 1 bis 3 und 5 gezeigten Rückschlagventiles mit dem sich in seiner Offenposition befindlichen Überdruckventil,
• 7 das hier in einem vergrößerten Längsschnitt dargestellte Rückschlagventil aus den 1 bis 3 und 5 in Schließposition seines Überdruckventils,
• 8 den Ventilkörper des in den 1 bis 3, 5 und 7 gezeigten Rückschlagventils mit dem sich in seiner Schließposition befindlichen Überdruckventil,
• 9 das hier ebenfalls längsgeschnittene Rückschlagventil aus den 1 bis 3, 5 und 7 in Offenposition seines Überdruckventiles und
• 10 den Ventilkörper des in den 1 bis 3, 5, 7 und 9 gezeigten Rückschlagventiles mit dem sich in seiner Offenposition befindlichen Überdruckventil.

It shows:

• 1 a non-return valve installed in a sanitary water line, in which a pressure relief valve is integrated,
• 2 the check valve off 1 in a longitudinal section, the valve body of the check valve being penetrated by an overpressure channel, in which overpressure channel the closing body of an overpressure valve can be moved from a closed position against a restoring force into an open position, and the valve body of the check valve being in its open position,
• 3 the check valve from the 1 and 2 with its valve body resting against a first valve seat, with the pressure relief valve integrated in the valve body also being in its closed position here,
• 4 the isolated valve body shown in a longitudinal section in the 1 until 3 shown non-return valve with the pressure relief valve integrated in it and located here in its closed position,
• 5 the check valve from which is also shown here in longitudinal section 1 until 3 in the closed position of its valve body, with the pressure relief valve integrated in the valve body being in its open position here,
• 6 the valve body in the 1 until 3 and 5 check valve shown with the pressure relief valve in its open position,
• 7 the check valve shown here in an enlarged longitudinal section from the 1 until 3 and 5 in the closed position of its pressure relief valve,
• 8th the valve body in the 1 until 3 , 5 and 7 check valve shown with the pressure relief valve in its closed position,
• 9 the here also longitudinally cut check valve from the 1 until 3 , 5 and 7 in the open position of its pressure relief valve and
• 10 the valve body in the 1 until 3 , 5 , 7 and 9 check valve shown with the pressure relief valve in its open position.

In the 1 until 3 , 5 , 7 and 9 a check valve 1 is shown, which can be used, for example, in the inflow direction in front of a single-lever mixing valve in the supply line 2 of a cold or hot water supply. The check valve 1 has a valve body 3, which from the inflowing water in the direction of flow from the 3 , 5 , 7 and 9 shown closed position, in which closed position the valve body 3 on a first valve seat 4 is tight against a restoring force in the in 2 shown open position is movable, in which the valve body 3 is lifted from the first valve seat 4. Since the valve body 3 is moved from its closed position to the open position by the water flowing in the usual flow direction Pf1, the water flowing in the usual flow direction Pf1 can pass through the check valve 1.

In contrast, a backflow flowing counter to the usual flow direction Pf1 presses the valve body 3 against the first valve seat 4, so that such backflows cannot flow through the valve seat 4 counter to the flow direction Pf1.

If the pressure on the outflow side of the check valve exceeds a specified maximum value and there is a risk of pressure-related destruction of the components located, for example, in a fitting arranged on the outflow side, a pressure relief valve 5 that is integrated in the check valve 1 comes into operation. This pressure relief valve 5 has a closing body 6 which, due to the pressure of the water flowing back counter to the flow direction Pf1, moves from a closed position, in which the closing body 6 lies tightly against a second valve seat 7, against a restoring force into an open position, in which open position the closing body 6 is lifted from the second valve seat 7, in the direction of the arrow Pf2 of the pressure relief valve 5 is movable. The restoring force acting on the closing body 6 of the pressure relief valve 5 is greater than the restoring force acting on the valve body 3 .

In the 4 and 6 until 10 It is easy to see that the closing body 6 of the pressure relief valve 5 has a closing body core 8 made of a first material, which closing body core 8 has a skin or a layer 9 made of a second, softer and/or more elastic material in its partial area that is in close contact with the second valve seat 7 in the closed position material wears. Since the layer 9 or skin surrounding the closing body core 8, at least in its partial region resting against the valve seat 7 of the pressure relief valve 5, consists of a material that is softer and/or more elastic than the closing body core 8, the closing body 6 of the pressure relief valve 5 can easily adapt to the second Create valve seat 7, with manufacturing tolerances being well compensated. Since the closing body 6 of the pressure relief valve 5 has a closing body core 8 made of a material that is harder than that and is not made of the same soft and/or elastic material as the skin or layer 9, excessive pressing of the closing body 6 into the valve seat 7 and the resulting Malfunctions of the pressure relief valve 5 avoided. The check valve 1 shown here is therefore also characterized in this respect by a high level of functional reliability even at high opening pressures of the pressure relief valve 5 .

The closing body 6 of the pressure relief valve 5 can also be designed as a two-component or multi-component plastic injection molded part.

As if from a synopsis of the 1 until 10 becomes clear, both the restoring force acting on the valve body 3 and the restoring force acting on the closing body 6 are each applied by at least one rubber or—as here—a resilient restoring element. The restoring elements associated with the valve body 3 or the closing body 6 are designed as compression springs 10 , 21 .

In the 1 until 3 , 5 , 7 and 9 it can be seen that the check valve 1 has a valve housing 11 and that the pressure relief valve 5 is integrated into the check valve 1 . In doing so, a synopsis of the 1 until 10 clear that the pressure relief valve 5 is integrated into the valve body 3 of the check valve 1. For this purpose, the valve body 3 of the check valve 1 is penetrated by a centrally arranged overpressure channel 12, in which overpressure channel 12 the closing body 6 is arranged to be movable between the closed position and the open position of the overpressure valve 5.

The second valve seat 7 assigned to the closing body 6 of the pressure relief valve 5 is formed by an annular surface which preferably widens conically counter to the flow direction Pf1. Since the closing body 6 has a ball-shaped or spherical segment shape, at least in its partial peripheral region that rests in the closed position on the second valve seat 7 and carries the skin or layer 9, the closing body 6 lies in the closed position of the pressure relief valve 5 only in a linear circumferential region on the annular surface of the second Valve seat 7 on.

The closing body 6 has an elongated shape here. The closing body 6 carries a pin 13, 14 both on its inflow side and on its outflow side. While the pin 13 arranged on the inflow side of the closing body 6 and oriented in the flow direction Pf1 has a cylindrical pin shape, that on the closing body 6 is on the outflow side arranged and counter to the direction of flow Pf1 oriented pin 14 formed truncated cone and tapers towards its free end of the pin.

So that the closing body core 8 carrying the elastic layer 9 does not dip into the clear opening cross section of the valve seat 7 and jam there, the closing body core 8 has a diameter which is larger than the smallest diameter of the valve seat 7 .

The closing body core 8 can be made from a comparatively hard thermoplastic material, for example from POM or PBT, or from any other suitable material. In contrast, the elastic skin or layer 9 is preferably made of silicone. The skin or layer 9 can have a layer thickness of 0.10 to 0.50 mm, preferably 0.15 to 0.40 mm and in particular 0.17 to 0.32 mm. It is advantageous if this skin or layer 9 has a Shore hardness of 30° to 100° Sh-A, preferably 70° to 90° Sh-A.

The valve seat 7 of the pressure relief valve 5 is preferably made from a hard material and in particular from a hard thermoplastic material. From a comparison in particular 8th and 10 it becomes clear that the pressure relief valve 5 in its in 10 shown open position opens only so far that the check valve 1 in the region of the valve seat 7 of its pressure relief valve 5 is leaking. The closing body 6 of the pressure relief valve 5 lifts only slightly from the valve seat 7 in order to release the water path for a small portion of the overpressure water present on the outflow side and to reduce the overpressure accordingly.

In the 7 and 9 It can be seen that when the check valve 1 shown here is installed, the closing body 6 is first pushed into the overpressure channel 12 with its pin 13 oriented in the flow direction Pf1 of the check valve. After the compression spring 10 serving as a restoring force has been placed on the outflow-side pin 14 oriented counter to the flow direction Pf1 of the check valve, the overpressure channel 12 is narrowed with a sleeve-shaped plug 15, which plug 15 clamps the compression spring 10 between itself and the closing body 6 of the overpressure valve 5 .

The check valve 1 has a valve housing 11 which carries a pocket-shaped spring receptacle 16 on its outflow side. The compression spring 21 serving as a restoring force is inserted in this spring receptacle 16 in such a way that this compression spring 21 is clamped between the spring receptacle 16 and the outflow side of the valve body 3 . The valve body 3 is formed here approximately mushroom-shaped. An annular seal 17 is provided on the valve seat 4 of the check valve 1, against which annular seal 17 the valve body 3 rests tightly when the check valve 1 is in the closed position. On the outer circumference of the valve housing 11 there is a sealing ring 18 which seals the annular gap between the outer circumference of the valve housing 11 and the inner circumference of the inlet line 2 accommodating the valve housing 11 of the check valve 1 . On the circumference of the valve housing 11 , locking arms 19 protrude outwards and, when the check valve 1 is in the operating position, are supported on an annular shoulder on the inner circumference of the inlet line 2 . The valve housing 11 is inserted into an insertion opening 20 of the inlet line 2, which insertion opening 20 is designed as a cross-sectional enlargement of this inlet line 2.

Reference List

1

check valve

2

inlet line

3

valve body

4

(first) valve seat of check valve 1

5

pressure relief valve

6

closing body

7

(second) valve seat of the pressure relief valve 5

8th

closing body core

9

layer

10

Compression spring of the pressure relief valve

11

valve body

12

overpressure channel

13

inflow direction Pf1 of the check valve oriented inflow-side pin on the closing body 6

14

outflow-side pin on the closing body 6 oriented counter to the flow direction Pf1 of the check valve

15

Plug

16

spring mount

17

ring seal

18

sealing ring

19

locking arms

20

insertion hole

21

Check valve compression spring

pf1

Flow direction of the check valve 1

Pf2

Flow direction of the pressure relief valve 5

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• EP 0653033 B1 [0003]

Claims (19)

Non-return valve (1) with a valve body (3) which (3) from the water flowing in the flow direction (Pfl) from a closed position, in which closed position the valve body (3) rests tightly against a first valve seat (4), against a restoring force in an open position, in which the valve body (3) is lifted off the first valve seat (4), and with a pressure relief valve (5) which (5) has a closing body (6) which (6) is counteracted by the pressure of the direction (Pfl) of water flowing back from a closed position, in which the closing body (6) lies tightly against a second valve seat (7), against a restoring force into an open position, in which open position the closing body (6) is lifted off the second valve seat (7). is movable, the restoring force acting on the closing body (6) of the pressure relief valve (5) being greater than the restoring force acting on the valve body (3), characterized in that the Closing body (6) of the pressure relief valve (5) has a closing body core (8) made of a first material, which closing body core (8) has a skin or a layer (9) made of a second , on the other hand softer and/or elastic material. check valve after claim 1 , characterized in that the closing body (6) of the pressure relief valve (5) is designed as a two-component or multi-component plastic injection molded part. check valve after claim 1 or 2 , characterized in that the restoring force acting on the valve body (3) and/or the restoring force acting on the closing body (6) is applied by at least one rubber or spring-elastic restoring element. Check valve according to one of Claims 1 until 3 , characterized in that the at least one restoring element (21; 10) is designed as a compression spring. Check valve according to one of Claims 1 until 4 , characterized in that the check valve (1) has a valve housing (11) and that the pressure relief valve (5) is integrated into the check valve (1). Check valve according to one of Claims 1 until 5 , characterized in that the pressure relief valve (5) is integrated into the valve body (3). Check valve according to one of Claims 1 until 6 , characterized in that the valve body (3) passes through a particularly centrally arranged overpressure channel (12), in which overpressure channel (12) the closing body (6) is arranged to be movable between the closed position and the open position of the overpressure valve (5). Check valve according to one of Claims 1 until 7 , characterized in that the second valve seat (7) is formed by an annular surface, which preferably widens conically counter to the direction of flow (Pfl). Check valve according to one of Claims 1 until 8th , characterized in that the closing body (6), at least in its closed position on the valve seat (7) abutting and / or the skin or layer (9) carrying peripheral portion has a ball or spherical segment shape. Check valve according to one of Claims 1 until 9 , characterized in that the closing body (6) carries a pin (13; 14) on its inflow side and/or on its outflow side. check valve after claim 10 , characterized in that the on the closing body (6) arranged on the inflow side and in the flow direction (Pfl) oriented pin (13) has a cylindrical pin shape. check valve after claim 10 or 11 , characterized in that the on the closing body (6) arranged on the outflow side and counter to the flow direction (Pfl) oriented pin (14) tapers towards its free pin end and is preferably designed in the shape of a truncated cone. Check valve according to one of Claims 1 until 12 , characterized in that the closing body core (8) has a diameter which is larger compared to the smallest diameter of the valve seat (7). Check valve according to one of Claims 1 until 13 , characterized in that the closing body core (8) is made of a thermoplastic material, in particular made of POM or PBT plastic. Check valve according to one of Claims 1 until 14 , characterized in that the elastic skin or layer (9) consists of silicone. Check valve according to one of Claims 1 until 15 , characterized in that the skin or layer (8) has a layer thickness of 0.10 to 0.50 mm, preferably 0.15 to 0.32 mm and in particular 0.15 to 0.22 mm. Check valve according to one of Claims 1 until 16 , characterized in that the skin or layer (9) has a Shore hardness of 30° to 100° Sh-A, preferably 70° to 90° Sh-A. Check valve according to one of Claims 1 until 17 , characterized in that the check valve (1) in the region of its second valve seat (7) is made of a hard material and/or a hard or hard-elastic thermoplastic material. Check valve according to one of Claims 1 until 18 , characterized in that the skin or layer (9) is made of an elastomer, preferably rubber, silicone or a thermoplastic elastomer.

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