Safety fitting

Abstract

Safety fitting (10), with a housing (11), with a backflow preventer (12) for interrupting a connection for a liquid between a first zone (14) and a second zone (15), with a drain valve (13) for emptying the second zone (15) of the liquid, wherein both the backflow preventer (12) and the drain valve (13) comprise a blocking element (16, 18) and a valve seat (17, 19) which are movable relative to one another, wherein the blocking element (16) of the backflow preventer (12) and the blocking element (18) of the drain valve (13) are formed by a common, pot-like element (20) which prevents the backflow preventer (12) and the drain valve (13) from being in an open position at the same time, wherein a bottom (21) of the pot-like element (20) is part of the blocking element (16) of the backflow preventer (12) and a wall (22) of the pot-like element (20) is part of the blocking element (18) of the drain valve (13), and wherein at least one recess (23) is formed in the wall (22) of the pot-like element (20), which recess is in operative connection with an overflow channel (24) of the housing (11) at least when the backflow preventer (12) is open, characterized in that the pot-like element (20) has a first section (20A) comprising the bottom (21) and having a first outer diameter (d A1 ) and a first inner diameter (d I1 ) and a second section (20B) with a second outer diameter (d A2 ) and a second inner diameter (d I2 ), wherein the second outer diameter (d A2 ) larger than the first outer diameter (d A1 ) is, the housing (11) has a first housing section (11A) guiding the first section (20A) of the pot-like element (20), the inner diameter (d I3 ) to the first outer diameter (d A1 ), and a second housing section (11B) guiding the second section (20B) of the pot-like element (20), the inner diameter (d I4 ) to the second outer diameter (d A2 ) is adapted, the housing (11) forms the overflow channel (24) between the first housing section (11A) and the second housing section (11B), which overflow channel merges into a stop (25) cooperating with the second section (20B) of the pot-like element (20), the inner diameter (d I5 ) of the overflow channel (24) immediately adjacent to the stop (25) is at most as large as the second inner diameter (d I2 ).

Description

[0001] The invention relates to a safety fitting according to the preamble of patent claim 1.

[0002] A safety valve is used to protect drinking water in the pipes of a drinking water system and supply systems. Safety valves thus prevent contamination of drinking water by non-potable water. Safety valves designed as backflow preventers and system separators are known in practice. In a system separator, two backflow preventers are connected in series to ensure even greater protection of drinking water against contamination than a simple backflow preventer.

[0003] EP 1 801 298 B1 discloses a safety valve designed as a system separator. This known system separator has a first, inlet-side backflow preventer, a second, outlet-side backflow preventer, and a drain valve. The inlet-side backflow preventer serves to interrupt a fluid connection between a first, so-called upstream pressure zone and a second, so-called intermediate pressure zone. The outlet-side backflow preventer serves to interrupt a fluid connection between the second, so-called intermediate pressure zone and a third, so-called downstream pressure zone. The drain valve serves to empty the second, so-called intermediate pressure zone of fluid.

[0004] According to EP 1 801 298 B1, a blocking element of the first, inlet-side non-return valve and a blocking element of the discharge valve are formed by a common, pot-like element.

[0005] The pot-shaped element prevents the first, inlet-side backflow preventer and the drain valve from simultaneously assuming an open position. A base of the pot-shaped element forms part of the blocking element of the first, inlet-side backflow preventer, and a wall of the pot-shaped element forms part of the blocking element of the drain valve. Recesses are formed in the wall of the pot-shaped element. When the first, inlet-side backflow preventer is open, these recesses are operatively connected to an overflow channel formed as a groove in a wall of a safety valve housing that accommodates the first, inlet-side backflow preventer and the drain valve.

[0006] The safety fitting of EP 1 801 298 B1 does not require the second, outlet-side backflow preventer, in which case it would no longer be a system separator.

[0007] The problem is that water can collect in the groove of the wall of the safety valve housing, which houses the first backflow preventer and the drain valve, and thus in the overflow channel. This prevents the safety valve from being completely drained, especially when installed horizontally.

[0008] There is a need for a safety valve that can be completely drained. The invention is based on the object of creating a novel safety valve.

[0009] This object is achieved by a safety fitting according to patent claim 1.

[0010] The pot-like element has a first portion encompassing the base, having a first outer diameter and a first inner diameter, and a second portion having a second outer diameter and a second inner diameter, wherein the second outer diameter is larger than the first outer diameter. Preferably, the second inner diameter is also larger than the first inner diameter.

[0011] The housing has a first housing section guiding the first section of the pot-like element, the inner diameter of which is adapted to the first outer diameter, and a second housing section guiding the second section of the pot-like element, the inner diameter of which is adapted to the second outer diameter.

[0012] The housing forms the overflow channel between the first housing section and the second housing section of the housing, which merges into a stop that interacts with the second section of the pot-like element.

[0013] The inner diameter of the overflow channel immediately adjacent to the stop is at most as large as the second inner diameter of the pot-like element.

[0014] The above features combined ensure complete drainage of the safety valve via the drain valve when the backflow preventer closes. There is no risk of water accumulating in the overflow channel.

[0015] According to an advantageous development of the invention, the inner diameter of the overflow channel immediately adjacent to the stop is smaller than the second inner diameter. This is particularly preferred to prevent water from accumulating in the overflow channel.

[0016] According to an advantageous development of the invention, the first section of the pot-shaped element transitions gradually into the second section of the pot-shaped element. The first housing section transitions continuously into the second housing section via the overflow channel. This is particularly preferred to prevent water from accumulating in the overflow channel.

[0017] Preferred developments of the invention will become apparent from the dependent claims and the following description. An exemplary embodiment of the invention, without being limited thereto, is explained in more detail below with reference to the drawing. The drawing shows: Fig. 1 a safety fitting according to the invention in cross section in a first state; Fig. 2 the safety fitting according to the invention in cross section in a second state; Fig. 3 the safety fitting according to the invention in cross section in a third state; Fig. 4 the safety fitting according to the invention in cross section in a fourth state; Fig. 5 a detail of the safety fitting according to the invention in perspective view; Fig. 6 a modification of the safety fitting according to the invention in cross section in a state corresponding to the Fig. 3 corresponding condition.

[0018] The present invention relates to a safety fitting.

[0019] Fig. 1 to 4 show a cross section through a safety fitting according to the invention according to a preferred embodiment in several different states.

[0020] The safety fitting 10 according to the invention has a housing 11, wherein the housing 11, in the illustrated embodiment, accommodates a backflow preventer 12 and a drain valve 13. The backflow preventer 12 serves to interrupt a connection for a fluid between a first zone 14 and a second zone 15. The drain valve 13 serves to drain the second zone 15 of the fluid.

[0021] The backflow preventer 12 has a blocking element 16 and a valve seat 17. When the blocking element 16 of the backflow preventer 12 rests against the valve seat 17 of the backflow preventer 12, the flow of the liquid between the first zone 14 and the second zone 15 is interrupted.

[0022] The shut-off valve 13 also has a blocking element 18 and a valve seat 19. When the blocking element 18 of the drain valve 13 rests against the valve seat 19 of the blocking element 13, the second zone 15 cannot be emptied of the liquid.

[0023] The blocking element 16 of the backflow preventer 12 and the blocking element 18 of the drain valve 13 are provided by a common, pot-like element 20. The pot-like element 20 is designed such that the first backflow preventer 12 and the drain valve 13 cannot be in an open position at the same time.

[0024] Fig. 1 shows that when the non-return valve 12 is in the closed position, the drain valve 13 is open.

[0025] About the intermediate positions of the Fig. 2 and Fig. 3, the non-return valve 12 is moved from its closed position of the Fig. 1 out into the open position of the Fig. 4 transferred.

[0026] In Fig. 2, the shut-off valve 13 is just closed and remains closed even if the pot-like element 20 moves further to the right.

[0027] In Fig. 3, the backflow preventer 12 is just closed. In Fig. 2 and Fig. 3, the backflow preventer 12 and the shut-off valve 13 are both closed.

[0028] In Fig. 4, in which the non-return valve 12 is open, the shut-off valve 13 is closed.

[0029] The pot-like element 20, which provides on the one hand the blocking element 16 of the backflow preventer 12 and on the other hand the blocking element 18 of the drain valve 13, has sections 20A and 20B with different diameters.

[0030] A first section 20A of the pot-like element 20 has a bottom 21 and a first wall section 22A of a wall 22 which is tubular or cylindrically contoured and has a first outer diameter d A1 and a first inner diameter d I1 The bottom 21 of the first section 20A of the pot-like element 20 is part of the blocking element 16 of the backflow preventer 12.

[0031] A second section 20B of the pot-like element 20 adjoining the first section 20A has a second wall section 22B of the wall 22, which is contoured in a tubular or cylindrical manner and has a second outer diameter d A2 and a second inner diameter d I2 The second wall section 22B of the second section 20B of the pot-like element 20 is part of the blocking element 18 of the drain valve 13.

[0032] The second outer diameter d A2of the second section 20B is larger than the first outer diameter d A1 of the first section 20A.

[0033] The housing 11 has two housing sections 11A, 11B, which are adapted to the two sections 20A, 20B of the pot-like element 20.

[0034] Thus, a first housing section 11A serves to guide the first section 20A of the pot-like element 20, the inner diameter d I3 of the first housing section 11A is connected to a first outer diameter d A1 of the first portion 20A of the pot-like element 20.

[0035] The second section 20B of the pot-like element 20 is guided in the second housing section 11B, wherein the inner diameter d I4 of the second housing section 11B to the outer diameter d A2 of the second portion 20B of the pot-like element 20.

[0036] The bottom 21 of the pot-like element 20, which is part of the first section 20A of the pot-like element 20, is part of the blocking element 16 of the backflow preventer 12. The second wall section 22B of the second section 20B of the pot-like element 20 is part of the blocking element 18 of the drain valve 13.

[0037] In the wall section 22A of the first section 20A of the pot-like element 20, as best Fig. 5 can be removed, recesses 23 are introduced. The recesses 23 in the wall section 22A of the section 20A of the pot-like element 20 are positioned between the blocking element 16 of the backflow preventer 12 and the blocking element 18 of the drain valve, i.e. between the bottom 21 of the pot-like element 20 and the second wall section 22B of the second section 20B of the pot-like element 20.

[0038] When the non-return valve 12 is open, the recesses 23 interact with an overflow channel 24 and allow the liquid to flow from the first zone 14 into the second zone 15 when the drain valve 13 is closed.

[0039] The housing 11 forms the overflow channel 24 between the first housing section 11A and the second housing section 11B. The overflow channel 24 preferably merges into a stop 25 for the second section 20B of the pot-like element 20 adjacent to the second housing section 11B, in which the section 20B of the pot-like element 20 is guided.

[0040] It can be seen from the figures that the first section 20A or first wall section 22A of the pot-like element 20 transitions step-like into the second section 20B or second wall section 22B of the pot-like element 20. Accordingly, the first outer diameter d A1 stepwise into the second outer diameter dA2 as well as the first inner diameter d I1 stepwise into the second inner diameter d I2 above.

[0041] The transition from the first housing section 11A to the second housing section 11B is not step-like, but rather continuous, forming the overflow channel 24. The inner diameter d I5 of the overflow channel 24 adjacent to the stop 25 is at most as large as the second inner diameter d I2 of the second portion 20B of the pot-like element 20. Preferably, the inner diameter d I5 of the overflow channel 24 immediately adjacent to the stop 25 is smaller than the second inner diameter d I2 of the second portion 20B of the pot-like element 20.

[0042] The above contouring of the pot-like element 20 with the two sections 20A, 20B as well as the above dimensioning of the outer diameters d A1 , d A2of the two sections 20A, 20B of the pot-like element 20 as well as the dimensioning of the inner diameters d I2 and d I5 The arrangement of the second section 20B of the pot-shaped element 20 and the overflow channel 24 immediately adjacent to the stop 25 allows the safety fitting 10 to be completely emptied via the drain valve 13 when the backflow preventer 12 closes. There is no risk of water collecting in the safety fitting 10 when the backflow preventer 12 closes.

[0043] Fig. 1 to 4 further show connecting elements 27, 28 which engage on different sides of the housing 11 and which serve to connect the safety fitting 10 to a pipeline network, hydrant or the like.

[0044] In the embodiment of the Fig. 1 to 4, the pot-like element 20 carries at least one sealing element 29, 30 and 31, respectively, in the area of section 20A and in the area of section 20B. Thus, in the exemplary embodiment, the Fig. 1 to 4, the section 20A of the pot-like element 20, the sealing element 29 and the section 20B of the pot-like element 20, the two sealing elements 30 and 31. The sealing element 29 of the section 20A of the pot-like element 20 serves to seal the blocking element 16 of the backflow preventer 13 and the sealing element 31 of the second section 20B of the pot-like element 20 serves to seal the blocking element 18 of the drain valve 13. As Fig. 1 to 4, passes over the displacement of the pot-like element 20 starting from the state of Fig. 1 in the state of Fig. 2 the sealing element 31 a drain opening 32 of the drain valve 13.

[0045] In the variant of the Fig.6, the sealing element 31, which serves to seal the blocking element 18 of the drain valve 13, is not integrated into the wall section 22B of the second section 20B of the pot-like element 20, but rather into the second housing section 11B of the housing 11 of the safety fitting 10.

[0046] A second non-return valve (not shown) can be integrated into the bottom 21 of the pot-like element 20, which is connected in parallel to the non-return valve 12 and which, in the open state, allows the liquid to flow through the bottom 21 of the pot-like element 20 parallel to the overflow channel 24.

[0047] When such a second non-return valve (not shown) is open, it also allows the liquid to flow from the first zone 14 into the second zone 15, but not via the overflow channel 24 like the non-return valve 12, but parallel thereto via the bottom 21 of the pot-like element 20. As a result, when the non-return valves are open and connected in parallel, the volume flow from the first zone 14 into the second zone 15 can be increased.

[0048] Furthermore, a third backflow preventer (not shown) may be provided to interrupt a connection for the liquid between the second zone and a third zone, wherein the third backflow preventer is connected in series to the backflow preventer 12 and optionally in series to a second backflow preventer (not shown), which in turn is connected in parallel to the backflow preventer 12. The backflow preventer 12 and the second backflow preventer (not shown), optionally connected in parallel to the backflow preventer 12, then each form inlet-side backflow preventers of a safety fitting designed as a system separator, wherein the third backflow preventer (not shown) is then an outlet-side backflow preventer of the system separator. List of reference symbols 10 Safety fitting 11 housings 11A first housing section 11B second housing section 12 backflow preventers 13 Drain valve 14 first zone 15 second zone 16 Locking element 17 Valve seat 18 Locking element 19 Valve seat 20 pot-like element 20A first section 20B second section 21 Floor 22 wall 22A wall section 22B Wall section 23 Recess 24 overflow channel 25 stops 26 Spring element 27 Connection element 28 connecting element 29 Sealing element 30 Sealing element 31 Sealing element

Claims

[1] Safety fitting (10), with a housing (11), with a backflow preventer (12) for interrupting a connection for a liquid between a first zone (14) and a second zone (15), with a drain valve (13) for emptying the second zone (15) of the liquid, wherein both the backflow preventer (12) and the drain valve (13) comprise a blocking element (16, 18) and a valve seat (17, 19) which are movable relative to one another, wherein the blocking element (16) of the backflow preventer (12) and the blocking element (18) of the drain valve (13) are formed by a common, pot-like element (20) which prevents the backflow preventer (12) and the drain valve (13) from being in an open position at the same time, wherein a bottom (21) of the pot-like element (20) is part of the blocking element (16) of the backflow preventer (12) and a wall (22) of the pot-like element (20) is part of the blocking element (18) of the drain valve (13), and wherein at least one recess (23) is formed in the wall (22) of the pot-like element (20), which recess is in operative connection with an overflow channel (24) of the housing (11) at least when the backflow preventer (12) is open, characterized by , that the pot-like element (20) has a first section (20A) comprising the base (21) and having a first outer diameter (d A1 ) and a first inner diameter (d I1 ) and a second section (20B) with a second outer diameter (d A2 ) and a second inner diameter (d I2 ), wherein the second outer diameter (d A2 ) larger than the first outer diameter (d A1 ) is, the housing (11) has a first housing section (11A) guiding the first section (20A) of the pot-like element (20), the inner diameter (d I3 ) to the first outer diameter (d A1 ), and a second housing section (11B) guiding the second section (20B) of the pot-like element (20), the inner diameter (d I4 ) to the second outer diameter (d A2 ) is adapted, the housing (11) forms the overflow channel (24) between the first housing section (11A) and the second housing section (11B), which merges into a stop (25) cooperating with the second section (20B) of the pot-like element (20), the inner diameter (d I5 ) of the overflow channel (24) immediately adjacent to the stop (25) is at most as large as the second inner diameter (d I2 ). [2] Safety fitting according to claim 1, characterized by that the inner diameter (dI5 ) of the overflow channel (24) immediately adjacent to the stop (25) is smaller than the second inner diameter (d I2 ). [3] Safety fitting according to claim 1 or 2, characterized by that the second inner diameter (d I2 ) larger than the first inner diameter (d I1 ) is. [4] Safety fitting according to one of claims 1 to 3, characterized by that the first section (20A) of the pot-like element (20) transitions step-like into the second section (20B) of the pot-like element (20). [5] Safety fitting according to claim 4, characterized by that the first outer diameter (d A1 ) gradually into the second outer diameter (d A2 ) and the first inner diameter (d I1 ) gradually into the second inner diameter (d I2 ) passes over. [6] Safety fitting according to one of claims 1 to 5, characterized bythat the first housing section (11A) merges continuously into the second housing section (11B) via the overflow channel (24). [7] Safety fitting according to one of claims 1 to 6, characterized by that the first section (20A) of the pot-like element (20) comprises the bottom (21) and a first wall section (22A) of the wall (22) with the first outer diameter (d A1 ) and the first inner diameter (d I1 ), wherein the bottom (21) of the pot-like element (20) is part of the blocking element (16) of the backflow preventer (12), the second section (20B) of the pot-like element (20) has a second wall section (22B) of the wall (22) with the second outer diameter (d A2 ) and the second inner diameter (d I2 ), wherein the second wall section (22B) of the wall (22) of the pot-like element (20) is part of the blocking element (18) of the drain valve (13). [8] Safety fitting according to one of claims 1 to 7, characterized by that a second non-return valve is integrated into the bottom (21) of the pot-like element (20), which second non-return valve is connected in parallel to the non-return valve (12) and which, in the open state, releases a flow of the liquid through the bottom (21) of the pot-like element (20) parallel to the overflow channel (24). [9] Safety fitting according to one of claims 1 to 8, characterized by a third backflow preventer for interrupting a connection for the liquid between the second zone (15) and a third zone, the third backflow preventer being connected in series to the backflow preventer (12) and optionally in series to a second backflow preventer which in turn is connected in parallel to the backflow preventer (12). [10] Safety fitting according to claim 9, characterized bythat the backflow preventer (12) and a second backflow preventer, optionally connected in parallel to the backflow preventer (12), are each inlet-side backflow preventers of a safety fitting designed as a system separator, and that the third backflow preventer is an outlet-side backflow preventer of the system separator.

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