Automatic valve for fire suppression and fire suppression systems

Abstract

An automatic valve (1) for fire-fighting and fire-suppression systems comprises a valve body (2), a cylindrical piston (13), and a cover (4). The valve body (2) has a central longitudinal bore (6) extending along its longitudinal axis, into which connection bores (7) extending transversely to the longitudinal axis open. The valve body (2) further has a connection end (5) for reversible connection to a pressure vessel and a cover end (3) opposite the connection end (5) for reversible connection to the cover (4), wherein the cover (4) has a bore (10) with an internal thread arranged offset to the longitudinal axis of the valve body (2). The connection end (5) has an inner diameter that is smaller than an inner diameter of the longitudinal bore (6) of the valve body (2).The piston (13) is movable axially along the longitudinal axis in the longitudinal bore (6) of the valve body (2) between a first and a second end position, wherein in its first end position it rests on a circumferential edge (8) formed by the connection end (5). The piston (13) has an end near the cover and an end near the connection end, each end comprising a circumferential groove (15) for receiving a sealing means that can be brought into operative contact with an inner circumferential surface of the valve body (2).

Description

[0001] The invention relates to an automatic valve for fire fighting and fire suppression systems.

[0002] Automatic fire fighting and suppression systems are critical for protecting life and property by quickly extinguishing fires. These systems use valves to optimally control the release of extinguishing agents such as powder, foam, liquids, or gases into the area affected by fire or smoldering fires. The effectiveness of these systems depends heavily on the performance and reliability of the valves used.

[0003] Firefighting systems comprise a pressure vessel containing a fire-extinguishing medium, such as nitrogen. The pressure vessel is usually reversibly connected to a valve. A pressure gauge is attached to the valve. A sensor line for automatically detecting a fire and an extinguishing line for releasing the fire-extinguishing medium during the extinguishing process are also connected to the valve. The sensor line is pressurized via the valve with a system pressure that is lower than the pressure in the pressure vessel. The system pressure is, for example, 15 to 20 bar, although the pressure in the pressure vessel can be up to 360 bar.

[0004] In the event of a fire, a portion of the sensor line bursts at a location closest to the source of the fire. The resulting pressure drop activates the extinguishing system, with the appropriate fire extinguishing agent being introduced into the extinguishing line via the valve. Fire extinguishing systems are known, for example, from DE 10 2010 028 858 A1 and EP 3 744 405 A1.

[0005] DE 10 2010 028 858 A1 describes a valve with a valve housing in which a pressure control unit is arranged for regulating a low pressure in a low-pressure chamber of the valve housing relative to a vessel pressure of the pressure vessel. For this purpose, the pressure control unit is in pressure communication with the pressure vessel via a valve inlet opening and with the low-pressure chamber. The low-pressure chamber serves to connect a triggering device, in particular a sensor line. Because the pressure control unit maintains a low pressure in the low-pressure chamber that is regulated, in particular reduced, relative to the vessel pressure, the pressure load on the valve and the sensor line is reduced.

[0006] An automatic valve is known from US 2020 / 0114186 A1.

[0007] DE 10 2015 203 486 A1 describes a sectional valve for an extinguishing agent line with a working valve and a control valve that controls the working valve. In order to achieve greater flexibility with regard to adjustment options and / or use or operation, the control valve has, for example, a control spring that presses the armature onto the control valve seat and against which the control coil lifts the armature from the control valve seat, a permanent magnet that, in an actuated state, is designed to hold the armature lifted from the control valve seat by means of the core, and a magnet holder in and / or on which the permanent magnet is held in the actuated state and which allows removal of the permanent magnet, wherein the control valve is designed for variable positioning of the core along a force exerted by the control spring.

[0008] Common valves for firefighting systems consist of multiple components, potentially subject to multiple failure points because they require precise alignment and sealing. This leads to leaks that compromise the reliability of the entire firefighting system. Furthermore, after the system is triggered, i.e., after the fire extinguishing agent has escaped, such complex valves must be completely replaced.

[0009] Another problem with known, state-of-the-art valves concerns the potential ingress of extinguishing agents from below the piston to above the piston (and eventually even into the pneumatic detection line). To prevent this unwanted ingress, existing valves often use check valves (which add further complexity to the system and thus prone to failure) or have a larger bore, typically around 0.5 mm, which may not be able to provide the required and precise throttling of the extinguishing agent flow.

[0010] Furthermore, the valve usually has to be removed after activation in order to refill the pressure vessel. This is because the valve bodies, which are usually designed in two parts, are screwed together after the piston is inserted and then additionally glued or pressed together for sealing. Opening the valve body is then impossible. The valve must be completely replaced after each activation, whether faulty or normal.

[0011] The invention is based on the object of providing a valve which does not have the disadvantages of the prior art.

[0012] The object is achieved by the features of claim 1. Preferred embodiments are described in the dependent claims.

[0013] The object is achieved according to the invention in that an automatic valve for fire fighting and fire suppression systems is provided, comprising a valve body, a cylindrical piston and a cover, wherein the valve body has a central longitudinal bore extending along its longitudinal axis, into which connection bores extending transversely to the longitudinal axis open and has a connection end for reversible connection to a pressure vessel and a cover end opposite the connection end for reversible connection to the cover, wherein the cover has a bore arranged offset to the longitudinal axis of the valve body with an internal thread, wherein the connection end has an inner diameter which is smaller than an inner diameter of the longitudinal bore of the valve body,The piston is axially movable in the longitudinal bore along the longitudinal axis between a first and a second end position and, in its first end position, rests on a circumferential edge formed by the connection end. The piston has an end close to the cover and an end close to the connection end, in particular far from the cover, and each end comprises a circumferential groove for receiving a sealing means that can be brought into operative contact with an inner circumferential surface of the valve body. The valve according to the invention can be easily maintained and reused after being triggered. Replacing the valve is not necessary. The valve body is accessible at any time by simply unscrewing the cover, so that, in the case of liquid extinguishing agents, the pressure vessel can also be refilled while installed.

[0014] In one embodiment, the valve body is constructed as a single piece. An advantage of this design is that separate components are eliminated, reducing the number of potential leaks while increasing the reliability and service life of the valve. Furthermore, by integrating all required valve body components into a single component, the manufacturing process can be simplified.

[0015] It may be provided that the connection end of the valve body has an internal thread for connection to a suction pipe assembly of the pressure vessel.

[0016] The piston is cylindrical in shape and, in one embodiment, can have a central region flanked by the grooves located at the ends. The diameter of the central region is preferably constant along its length, i.e., in the axial direction relative to the longitudinal axis.

[0017] The grooves are preferably equidistant from a central axis extending transversely to the longitudinal axis of the piston. In a preferred embodiment, the grooves have a substantially identical diameter. Two identical O-rings of the same size are advantageously located in the grooves as sealing means. The sealing means are preferably designed such that they come into contact with an inner circumferential surface of the valve body when inserted into the grooves. The preferred use of two substantially identical O-rings as sealing means ensures that a robust seal (with the same O-ring compression) is achieved.

[0018] The preferred arrangement of the sealing means in the form of O-rings advantageously ensures that in a high-pressure condition, neither extinguishing agent / nitrogen can penetrate into the extinguishing agent line from above or from below.

[0019] In one embodiment, the piston has a channel axially penetrating it along its longitudinal axis. It is also advantageous that the channel in the piston has a stepped bore configuration, with the diameter of the smaller bore being less than or equal to 0.3 mm. In contrast to known valves that rely on check valves or have a bore of 0.5 mm, a precise bore of only 0.3 mm in the piston is advantageous. Such a bore prevents the unwanted penetration of extinguishing agent below the piston and ensures efficient use of the system.

[0020] One design provides for a circumferential groove in the cover end facing axially towards the cover to accommodate a sealing ring. The sealing ring can be designed as an O-ring made of an elastomer. According to the state of the art, a two-part valve head is screwed together after the piston has been inserted and then glued / pressed together to seal. The valve body can then no longer be opened; instead, it must be replaced without replacement in the event of regular or faulty activation. The cover design, on the other hand, allows the cover to be easily unscrewed in the event of regular or faulty activation, the valve head to be serviced, and then screwed back on with a new O-ring. This significantly shortens maintenance work because the entire valve body does not need to be replaced and the connections on the valve body do not need to be unscrewed.The significant reduction in maintenance work and the reuse of the valve body are therefore very sustainable and bring immense cost advantages for the customer.

[0021] Furthermore, the invention relates to a firefighting and suppression system with at least one valve as described above, wherein at least one extinguishing line, a detection line, and a pressure vessel are connected to the valve body. The detection line is pneumatically connected to the valve body via the bore in the cover, the extinguishing line via at least one connection bore, and the pressure vessel via the connection end. During normal operation, the piston seals off the at least one connection bore to the extinguishing line with its circumferential surface. Furthermore, reference is made to the advantages and configurations of the valve, which are analogously applicable to the firefighting and suppression system.

[0022] The invention will be explained in more detail below with reference to an embodiment of the invention, which is illustrated in the drawing. Figure 1 a perspective view of a valve, Figure 2 a sectional view of the valve according to Figure 1 according to AA, Figure 3 a sectional view of section B of the valve according to Figure 1 , Figure 4 a side view of a piston, Figure 5 top view of a cover, Figure 6 a sectional view of the cover according to Figure 5 according to AA and Figure 7 a section of a sectional view of the lid according to Figure 5 to BB,

[0023] Figures 1 and 2show an embodiment of a valve. In the embodiment shown, the valve 1 comprises a one-piece valve body 2 with a cover end 3 for connection to a cover 4 and a connection end 5 opposite the cover end 3. The valve body 2 has a longitudinal bore 6 extending along its longitudinal axis. The longitudinal bore 6 is preferably cylindrical. Connection bores 7 running transversely to the longitudinal axis open into the longitudinal bore 6, via which lines can be connected to the valve body 2. Corresponding connection options, such as threads, plug connections or the like, can be provided and are known to those skilled in the art. Such connection bores 7 include, for example, but are not limited to, connections for extinguishing agents, a connection for a detection line and a connection for a pressure measuring device.

[0024] The connection end 5 can comprise a thread via which the valve 1 can be connected to a suction pipe or a suction pipe assembly of a pressure vessel, in particular an extinguishing agent container. The suction pipe can be attached to the suction pipe assembly using an internal thread. Alternatively, the suction pipe assembly can be designed long enough to function as a suction pipe. Furthermore, the suction pipe assembly can be screwed or pressed into the bore of the connection end. The bore of the connection end 5 is aligned coaxially with the longitudinal bore 6 of the valve body 2.

[0025] The connection end 5, in particular, has a smaller inner diameter than the longitudinal bore 6 of the valve body 2. This forms a circumferential edge 8, which is present between the longitudinal bore 6 of the valve body 2 and the bore of the connection end 5. The edge 8 is located axially below a connection bore 7, which is provided, in particular, for connecting an extinguishing line.

[0026] The cover 4 can, as shown in the Figures 5-7 As can be seen, the valve body 2 can be reversibly connected to the valve body 2 via fastening means. For this purpose, the valve body 2 can have corresponding threaded holes 9, into which, for example, screws guided through holes 10 in the cover can be inserted. In the valve body 2, more precisely in the cover end 3 facing in the axial direction towards the cover 4, there is a circumferential groove 11 for receiving a sealing ring. This allows the cover 4 to be sealingly connected to the valve body 2.

[0027] The cover 2 includes an off-center bore 12 that extends into the valve body 2 when the cover 4 is connected to the valve body 2. The bore 12 may have an internal thread. The pneumatic connection of the detection line is possible via the bore 12.

[0028] In the Figure 4a preferred piston 13 is shown in side view. The piston 13 is, for example, cylindrically shaped and has an end close to the cover and an end close to the connection end, in particular far from the cover. In particular, a central region 14 of the piston 13 is cylindrical and is flanked by two circumferential grooves 15 or constrictions for respectively receiving a sealing means that can be brought into operative contact with an inner circumferential surface of the valve body 2. The diameter of the central region 14 is preferably constant over the length of the piston 13. The outer contour of the piston 13 is preferably designed to match the contour of the longitudinal bore 6, so that the piston 13 is movable axially to the longitudinal axis of the valve body 2 in the longitudinal bore 6 between a first and a second end position. The person skilled in the art is aware that, in particular, unstable intermediate positions exist between the two end positions.

[0029] The grooves 15 are located at the end of the piston 13 near the cover and near the connection end, in particular far from the cover. The sealing means (not shown) can be made as an O-ring made of an elastomer and is preferably designed such that its diameter is larger than the diameter of the respective groove 15, so that the sealing means protrudes beyond the circumferential surface of the central region 14 of the piston 13. The sealing means thus lie sealingly against the inner surface of the longitudinal bore 6. The grooves 15 are preferably of the same size. The same applies to the sealing means that can be attached therein. Furthermore, the distance of the grooves 15 from a central axis, which runs transversely to the longitudinal axis of the piston 13, is essentially the same. This means that the grooves 15 and their position in the piston 13 are preferably mirror-symmetrical with respect to the aforementioned central axis.The ends of the piston 13, that is to say the end near the cover and the end near the connection end, in particular the end far from the cover, are delimited by a circumferential edge 16 which forms the free end of the piston 13.

[0030] Piston 13 is penetrated essentially axially along its central axis by a channel 17, which is designed as a stepped bore configuration. Channel 17, according to the illustrated design, essentially has two bores, with the diameter of the smaller bore being smaller than the diameter of the larger bore. The transition between the bores forming channel 17 can be conical.

[0031] The following illustrates the operation of one embodiment of the valve 1 by way of example. At least one extinguishing line is connected to the valve 1 via the corresponding connection bore 7 projecting into the valve body 2. Above this, a pressure measuring device can be connected to a connection bore 7. A detection line is pneumatically connected to the valve body 2 via the bore 10 in the cover 4. Furthermore, an extinguishing agent container is in pneumatic contact with the valve body 2 via the connection end 5. The piston 13 is movably received in the valve body 2, with the sealing means present in the grooves 15 being in operative contact with the inner surface of the valve body 2.

[0032] When the valve 1 is connected to a fire fighting and fire suppression system (not shown) as described, the preferred design of the valve 1 causes the piston 13 to be pressed downward in a high-pressure state against the edge 8 formed by the connection end 5, which thus serves as an axial stop, and the piston 13 is in its first stable end position. The pressure required for this is generated, for example, via a gas, e.g., nitrogen, introduced into the detection line. In this lower stable end position, the piston 13 sits sealingly on the suction pipe assembly so that no extinguishing agent can escape from the pressure vessel. The pneumatic area of ​​the end of the piston 13 near the connection end, in particular far from the cover, is smaller than the pneumatic area of ​​the end of the piston 13 near the cover, thereby generating a downward force on the piston 13.This state corresponds to normal operation in which the system is not triggered, i.e. no fire has been detected.

[0033] If a fire is detected, the pressure in the detection line is reduced, and thus the force acting on the piston 13. In this low-pressure state, the piston 13 lifts upwards from the connection end 5 due to the force acting on it from the direction of the pressure vessel, whereby the high and low pressure states each correspond to the pressure above the piston 13, which is equal to or lower than the system pressure in the detection line. The piston 13 moves upwards and, in the low-pressure state, simultaneously closes the upper connection bore 7 in the valve body 2 for the pressure measuring device and the bore 12 arranged in the cover for the detection line, so that a gas under pressure in the detection line cannot escape through the piston 13 and through a connection bore 7 in the valve body 2.The extinguishing agent escaping from the pressure vessel flows through the connection hole 7 released by the piston 13 into the extinguishing line to extinguish the fire.

[0034] The valve 1 according to the invention can significantly improve the reliability and efficiency of fire fighting and suppression systems. More specifically, the invention is a novel valve configuration that addresses various challenges encountered in existing valves for fire fighting and suppression systems.

[0035] Another key advantage of valve 1 is that it is reusable after activation. It is possible to unscrew the cover 4 and, if necessary, replace the piston 13 and / or the sealing elements. For this purpose, the cover 4 can be removed after disconnecting the detection line and removing the fastening elements.

[0036] Filling the pressure vessel with extinguishing agent is also possible after triggering with the valve 1 according to the invention without disassembly. For this purpose, a filling device (not shown) with a corresponding filling device connection can be screwed into the bore 12 in the cover 4. The extinguishing agent is conveyed into the pressure vessel via the longitudinal bore 6 of the valve body 2 and the channel 17 extending through the piston 12. It can be advantageous if a sleeve (not shown) is inserted into the longitudinal bore 6 of the valve body 2, which sleeve, on the one hand, lies over the connection bores 7 and, on the other hand, presses the piston 13 into its first end position. For this purpose, the cover 4 is detached from the valve body 2 and the sleeve is inserted before the cover 4 is replaced on the valve body and the filling device is connected to the bore 12 in the cover 4.The valve 1 according to the invention thus also enables the reuse of the valves 1 after activation and the filling of the pressure vessels without removing the valves 1. This represents a significant advantage over valves known from the prior art, since in these cases, replacement of the valves and the pressure vessels is necessary after activation. In contrast, the valve 1 according to the invention essentially enables the pressure vessels to be refilled during operation.

Claims

1. An automatic valve (1) for fire-fighting and fire-suppression systems, comprising a valve body (2), a cylindrical piston (13), and a cover (4), wherein the valve body (2) has a central longitudinal bore (6) extending along its longitudinal axis, into which connection bores (7) extending transversely to the longitudinal axis open, and a connection end (5) for reversible connection to a pressure vessel and a cover end (3) opposite the connection end (5) for reversible connection to the cover (4), wherein the cover (4) has a bore (10) arranged offset to the longitudinal axis of the valve body (2) and having an internal thread, wherein the connection end (5) has an internal diameter that is smaller than an internal diameter of the longitudinal bore (6) of the valve body (2),the piston (13) can be arranged in the longitudinal bore (6) so as to be movable axially along the longitudinal axis between a first and a second end position and, in its first end position, rests on a circumferential edge (8) formed by the connection end (5), wherein the piston (13) has an end close to the cover and an end close to the connection end, and each end comprises a circumferential groove (15) for receiving a sealing means which can be brought into operative contact with an inner circumferential surface of the valve body (2).

2. Automatic valve (1) according to claim 1, characterized in that the valve body (2) is designed in one piece.

3. Automatic valve (1) according to one of the preceding claims, characterized in that the connection end (5) has an external thread for connection to a suction pipe assembly of the pressure vessel.

4. Automatic valve (1) according to one of the preceding claims, characterized in thatthe piston (13) has a central region (14) with a constant diameter between the grooves (15).

5. Automatic valve (1) according to one of the preceding claims, characterized in that the grooves (15) are at an equal distance from a central axis running transversely to the longitudinal axis of the piston (13).

6. Automatic valve (1) according to one of the preceding claims, characterized in that the grooves (15) have the same diameter.

7. Automatic valve (1) according to one of the preceding claims, characterized in that two O-rings of the same size inserted into the grooves (15) are used as sealing means.

8. Automatic valve (1) according to one of the preceding claims, characterized in that the piston (13) has a channel (17) penetrating it axially along its longitudinal axis.

9. Automatic valve (1) according to claim 8, characterized in thatthe channel (17) in the piston (13) has a stepped bore configuration, the diameter of the smaller bore being less than or equal to 0.3 mm.

10. Automatic valve (1) according to one of the preceding claims, characterized in that in the cover end (3) there is a circumferential groove (11) pointing axially towards the cover (4) for receiving a sealing ring.

11. Firefighting and fire suppression system with at least one valve according to one of the preceding claims 1 to 10, wherein at least one extinguishing line, a detection line and a pressure vessel are connected to the valve body (2), wherein the detection line is pneumatically connected to the valve body (2) via the bore (12) present in the cover (4), the extinguishing line via at least one connection bore (7) and the pressure vessel via the connection end (5), wherein the piston (13) seals off the at least one connection bore (7) to the extinguishing line with its peripheral surface in normal operation.

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