NL2009972C2 - Domestic sprinkler head, domestic sprinkler system and method of installation thereof. - Google Patents

Description

Title: Domestic sprinkler head, domestic sprinkler system and method of installation thereof.

The invention relates to a sprinkler head, a 5 sprinkler system and a method of installation thereof. More specifically, the invention relates to a sprinkler configuration for domestic application.

The application of sprinklers in residential areas, domestic homes, dwellings and apartments can save 10 lives. If sprinklers can be installed cost effectively, the reduction in building damage and in medical treatment of fire victims and can outweigh the additional installation costs of the installation and maintenance of domestic sprinkler systems. Sprinkler systems can provide a prolonged 15 time spam for victims and may extinguish fire.

In the art, several domestic applications of sprinklers are known. The united states patent US6026907 and US6516893 elaborately describe deflector plate designs for residential sprinkler heads. The international application 20 W02006/060287 discloses a specially designed residential fire sprinkler. These sprinklers are designed to be in conformity with the regulations of the national fire protection agency (NFPA) 13, 13D and 13R...

However, since the above described sprinkler 25 systems are designed for relative high pressures. The above described sprinklers are currently required to supply 68 litres per minute (4.1 m3/h) when only one head is spraying and 84 litres per minute (5 m3/h), when two heads are spraying. These values are based on the NFPA standards, as 30 described in UL 1626 or NFPA 13D NFPA 13R. In these standards, a floor surface specific flow rate of (spray density) of 0.050 gallon per minute per square foot, (2.04 2 litre per minute/m2, 2.04 mm/minute) is kept as a minimum requirement.

In most European domestic area, because of the relative low water pressure, separate enhanced pressure 5 system pumps and enhanced pressure lines are needed for these sprinklers. This renders these systems complex and expensive .

The international application W02006/060287 does address the problem of lower water pressure in residential 10 areas, and suggests to enhance the orifice diameter of the sprinkler heads. Thus the minimum flow rates may be reached. However most drinking water systems cannot deliver the required amounts of water at the given pressures. Thus either vast adaptations to the drinking water need to be 15 carried out or, a separate sprinkler storage tanks need to be installed for the required sprinkler flow rates.

Accordingly it is an object of the invention to mitigate or solve the above described and/or other problems of sprinklers in the art, while maintaining and/or improving 20 the advantages thereof.

More specifically the object of the invention can be seen in providing a sprinkler and a sprinkler system that is relative simple and cost effective to install, that requires relative low additional plumbing and no alterations 25 to the existing water supply systems and that can be applied without additional high pressure pumps or voluminous sprinkler water reservoirs.

Furthermore advantageously such sprinkler systems require low maintenance and low operating costs.

30 These and/or other objects are reached by a sprinkler head, suitable to be installed in a drinking water line, having a US K-factor lower than approximately 3, preferably less than about 2.5. In SI units, the 3 corresponding K-factor should be less than approximately 44, preferably less than 36. This specific sprinkler head is suitable for low pressure, low flow rate domestic drinking water supply and is able to provide for a sufficient spray 5 distribution (specific flow rate) of 2.5 mm/minute over a sufficient area. The orifice diameter of this sprinkler head can be less than about 8 mm, or can preferably be less than about 7 mm. Thus a sufficient water distribution can be obtained with a non-modified water supply. This renders the 10 applicability of domestic sprinklers cost effective and in reach of residential real estate builders. Sprinkler heads of these type can potentially safe lives for a relative modest investment.

The orifice opening can advantageously have a 15 diameter of maximal 6,1 mm. Apparently orifices of this dimension and lower surprisingly perform very well. The invention further relates to a sprinkler system comprising at least one sprinkler head as described hereinabove.

The sprinkler heads can be mounted in proximity to 20 a ceiling and can have a distance between their centre line and a wall of about 500 to 1250 mm and a centre line-centre line distance between adjacent sprinklers of about 1500 to about 2500 mm. Thus the sprinkler heads are installed in a relative dense grid, such that sufficient water distribution 25 and specific flow rates (spray density) can be provided for.

The header of the sprinkler system can be directly connected to the main drinking water supply line entering the building in which the sprinkler system is installed.

Thus no additional pumps or storage containers are needed 30 for a safe sprinkler system, connected directly to the normal drinking water supply. In this sprinkler system, at least one group of sprinkler heads can comprise at least one sprinkler head, arranged on a group conduit, and the group 4 conduit can be on its first end connected to the water supply and a second end, it can be connected to a water take off, such as a washing machine, a water tap, a toilet, a shower, a boiler, a garden watering system and/or any other 5 water take off. Thus a sufficient flow through the system of drinking water can be obtained, such that no or relatively small dead volumes are provided.

The sprinkler heads within one room can have a first centre-centre distance of adjacent sprinklers of 10 between 1500 mm and 2500 mm. Thus optimal distribution is provided for, while no special adaptations are needed and the sprinkler heads can be connected to normal drinking water supply.

A non-return valve can be installed in each 15 sprinkler supply conduit proximate to the water conduit.

This can provide for a further reduction in contamination of the drinking water with the water resident in eventually given dead volumes of water in the sprinkler head supply conduits .

20 The invention further relates to a method of installing a sprinkler system as specified hereinabove, comprising the following steps: connecting a first end of a water conduit to a domestic drinking water supply; branching off a first end of a sprinkler supply conduit from the water 25 conduit and connecting a sprinkler head according to claim 1 at a second end of the sprinkler supply conduit; connecting a water off take at a second end of the water conduit, such that regular flow of water through the water conduit can be performed, wherein the water off take can be a tap, a 30 shower, a washing machine, a dish washer, a garden water supply, a boiler and/or any other water requiring off take.

5

Thus a simple and straight forward installation of a relative simple sprinkler system is provided, which can provide enhanced safety in domestic buildings.

For the requirements of the surface specific 5 water flow is set to 2,5 mm/min equalling 15 cm/h.

In order to further elucidate the invention, exemplary embodiments will be described with reference to the drawing. In the drawing:

Figure 1 depicts a first schematic view of a 10 domestic sprinkler system to an embodiment of the invention;

Figure 2 depicts a schematic top view of a spatial arrangement of a sprinkler system within a room according to an embodiment of the invention;

Figure 3 depicts a schematic diagram of a single 15 sprinkler head arrangement according to a further embodiment of the invention

Figure 4 depicts a schematic perspective view of a sprinkler head;

Figure 5 depicts a schematic cross sectional view 20 of the sprinkler head according to figure 4;

Figure 5A depicts a cross sectional view of a sprinkler head according to a further embodiment of the invention.

Figure 6 depicts a schematic diagram of the 25 relation between the US K-factor and the orifice diameter with sprinklers from the state of the art and with a sprinkler according to an embodiment of the invention;

Figure 6A depicts a schematic diagram of the relation between the SI K-factor and the orifice diameter 30 with the same sprinkler heads as depicted in figure 6;

Figure 7 depicts a schematic diagram with results of a specific flow rate (spray density) test of a sprinkler head according to an embodiment the invention; 6

Figure 7A depicts a schematic spray pattern of a sprinkler head according to an embodiment of the invention;

Figure 8 depicts a schematic diagram with results of a specific flow rate (spray density) test of a sprinkler 5 head according to the state of the art;

Figure 8A depicts a schematic spray pattern of a sprinkler head according to the state of the art.

The figures represent specific exemplary embodiments of the inventions and should not be considered 10 limiting the invention in any way or form. Throughout the description and the figures the same or corresponding reference numerals are used for the same or corresponding elements .

The expression "K-factor" used herein is to be 15 understood as, though not to be considered limited to be a descriptive parameter of sprinkler heads, being expressed as the flow rate in Gallons per minute divided by the square root of the gauge pressure over the sprinkler head. In brackets the K-factors in metric units is given.

20 The expression "connected to" and "in connection with" used herein in in relation to fluid lines, conduits, headers and the like is to be understood as, though not to be considered limited to meaning in fluid guiding contact or in fluid connection, without being directly open to the 25 surroundings. For example a fluid conduit in connection with a header means that fluid inside the headed can flow into the conduit without escaping to the surroundings.

The expression "distance between a wall and a sprinkler head" used herein is to be understood as, though 30 not to be considered limited to that distance measured from centre line of the sprinkler head in guestion to the wall in question, in a direction perpendicular to that specific wall.

7

The expression "directly connected to" used herein is to be understood as, though not to be considered limited to a fluid connection without a pump or other pressure or flow rate enhancing installation.

5 In figure 1, a schematic diagram of a sprinkler system 1 according to the invention is depicted. The sprinkler system 1 is fed by a water supply 2, which is connected to a water meter 3. From the water meter 3, a water supply header 4 is connected to the sprinkler system 10 1. The water supply header 4 is branched off in three groups I, II and III by means of water conduits 5, 6 and 7 respectively. Water conduit 5 is partially guided through a ceiling of a room, e.g. room 17 and is connected to sprinkler heads 12G and 12 I. further downstream water 15 conduit 5 is connected to a toilet 15 and a water tap 16. Water conduit 6 is similarly guided through a ceiling of a room, and in the portion running along the ceiling, three sprinkler heads 12D, 12 E and 12F are connected. Downstream of the sprinkler heads 12D-F a toilet 14 is installed. Water 20 conduit 7 has similarly a portion running along a ceiling and is in this portion provided with sprinkler heads 12A, 12B and 12C. Downstream of the sprinkler heads 12A-C the water conduit 7 is connected to a washing machine 13. The water supply header 4 can further be connected to a water 25 boiler feed conduit 8. This boiler feed conduit 8 is connected to a boiler 9 which can heat the water and deliver it to a hot water supply conduit 10.

The sprinklers according to the invention are designed to have a relative low K value, and are therefore 30 designed to be arranged in a specific installation pattern, which is depicted in more detail in figure 2.

In figure 2 a top view of a room 17 is depicted, which room 17 is provided with 6 sprinkler heads 18A, 18B, 8 18C, 18D, 18E and 18F. the room in this example is rectangular and surrounded by two relative short walls 20 and 22 and two relative long walls 19 and 21.

The sprinklers 18A, 18D, 18C and 18F are 5 positioned in corners of the room 17. The distances A

between wall 22 and the centre lines of the sprinkler heads 18A and 18D and between the sprinkler heads 18C and 18F and the wall 20 advantageously should not be larger than about 1250 mm and not be less than about 500 mm. In some cases the 10 distance to the wall may not be less than 300 mm or exceptionally, not less than 100 mm. Similarly, the distances B, between the walls 19 and the sprinkler heads 18A, 18B and 18c and the distance between the wall 21 and the sprinkler heads 18D, 18E and 18F should advantageously 15 not exceed 1250 mm and not be less than 500 mm.

The centre-centre distances between the sprinkler heads should not exceed 2500 mm and not be less than 1500 mm. The invention thus provides in a sprinkler head grid with a finer mesh than sprinkler systems in the art. Due to 20 the combination of this narrow grid, and sprinkler heads with a far lower K value, sufficient specific flow rates or spray densities can be obtained.

In order to prevent contamination of dead volumes with the drinking water supply, each sprinkler head may be 25 provided with a non-return valve 24, as is depicted in figure 3. The non-return valve 24 is installed close to the water conduit 7, where the T-connector 23 is installed. Thus the volume of water that resides in the connecting conduit 25 to the sprinkler head 12A can be shut off from the 30 drinking water supply. Only when the fuse of the sprinkler 12A is burst and the sprinkler is operating water can be allowed through the non-return valve 24.

9

In event the sprinkler head 12A is mounted at a distance from the water conduit 7, a non-return valve 24 can be advantageous.

The sprinklers can be made of alloys comprising 5 hazardous metals, such as zinc. Such sprinkler heads may be provided with a coating in order to prevent health threatening compounds to enter the drinking water. For instance a messing sprinkler can be provided with a lining of tin, silver and/or any other layer of any other organic 10 or inorganic protection.

In figure 4 a schematic perspective view of a sprinkler head 12 is depicted. In figure 5, a cross sectional view of this sprinkler head is presented. The sprinkler head typically comprises a thread for connection 15 to a conduit, a base 27 connecting a bracket 28 to the thread portion. The bracket 28 holding a distributor plate 31 and an adjusting screw 32. The adjusting screw 32 constricts and fixes a fuse or bulb 30 and a cap 29. The fuse or bulb 30 is cemented in the cap 29 by a cement 33 and 20 the cap snuggly fits into the orifice 34. The orifice 34 shape, the orifice diameter X and the geometries of the connecting section define the K-value of the sprinkler head.

Once the fuse or bulb 30 breaks due to heat, the cap 29 is no longer fixed and due to the water pressure 25 inside the sprinkler base, the cap is pushed out of the orifice and water starts to pour out of the sprinkler head 12 .

In figure 5A another sprinkler head is depicted. In this sprinkler head, both brackets 28 and deflector plate 30 (not shown) are one moulded part. The brackets 28 are inserted in the base 27 and fixed by means of pins 45. Between the cap 29 and the base 27, a coated spring ring 44 is positioned. The bulb or fuse 30 is clamped between the 10 brackets 28 and the cap 29, wherein the spring ring 44 can compensate for inaccuracies in the fuse or bulb. The ring 44 is coated with a sealing material, such that it seals of the inner water channel from the surroundings.

5 In the sprinkler head as depicted in figure 5A, again the orifice comprises a conical surface having an acute angle a, ending in a cylindrical surface, having a diameter X.

In figure 6 data points SI, S2, S3 and S4 10 represent a relation between the US K-value and the orifice diameter X of some sprinklers of the state of the art. In this figure, on the ordinate the K-factor is given and on the abscise the orifice diameter in mm is indicated. Furthermore one data point T of a sprinkler according to the 15 invention is depicted in the diagram as well.

In figure 6A, the same sprinkler heads are presented, in this figure however the K-factor according to SI unit is presented on the abscise instead.

It is noted that the K-value is further related to 20 the geometry of the sprinkler head. The geometry of the

sprinkler heads depicted in figure 6 and the one according to the invention are a non-restricted conical channel with a continuously decreasing diameter towards the orifice with an angle a between 2 and 15 degrees the conical section ends in 25 a cylindrical section with a diameter X, as is depicted in figure 5A

In figure 7 the results of a specific flow rate (spray density) test are depicted of a sprinkler head arrangement according to the invention. The sprinkler used 30 was provided with a conical channel with a decreasing inner diameter ending, without any restriction in an orifice having a diameter of 6.1 mm. The US K-value that was calculated from the obtained flow rate at the given pressure 11 was 1.47; in SI, K-value is calculated to be 22. Other relevant parameters are: the test area is a square area of 5000 mm wide and 5000 mm tall.

A series of 100 measurement vials (not visible) 5 are connected to collectors 35, wherein each collector 35 and its vial collects the water on a surface of 500 by 500 mm of surface area. Four sprinkler heads 36, 37, 38 and 39 according to the invention are hanging and installed at a distance of 275 mm from the ceiling and 2700 mm above the 10 measurement surface. The sprinkler heads are installed in a square grid arrangement with a distance between the sprinkler heads of 2500 mm. The sprinkler heads are connected to a water supply mimicking a normal domestic water supply, with a pressure over the sprinkler heads in 15 open position of 0.5 bars.

The diagram of figure 7 depicts a sufficient specific flow rate (spray density) as a solid square, insufficient specific flow rates (spray densities) are depicted as a outlined square, where a sufficient specific 20 flow rate is set according to the hereinabove mentioned 2.5 mm/min.

As can be seen in the diagram of figure 7, all except two vials show sufficient spray density, wherein a deviation of the requirement of three vials is still 25 considered acceptable.

The diagram of figure 8 depicts a similar arrangement, wherein sprinkler heads 40, 41, 42 and 43 of the state of the art is taken as a reference. The sprinkler heads are the one which is depicted in figure 6 as the 30 sprinkler head SI. The sprinkler head taken is the sprinkler head with the smallest K-value as currently commercially available, being a K value of 3.0, having a orifice diameter of 8.2 mm.

12

From the diagram it may be immediately clear that such a sprinkler heads 40-43 are not suitable for a domestic drinking water application; the water is predominantly collected in the vials directly under the sprinkler heads.

5 In this specific test 12 out of the 25 collectors 35 within the four sprinkler heads 40-43 are insufficiently provided with water. This leads to a unacceptable distribution of water, which is insufficient to provide for a safe fire fighting or a secured saving of inhabitants lives.

10 Without being bound to theory, it is believed that the orifices of state of the art sprinkler heads cannot provide for sufficient velocity of the water as to form a spray, when impinging on the deflector plate 31.

The sprinkler heads from the state of the art 15 insufficiently provide for wall wetting as is depicted in figure 8A. In this figure schematically a spray pattern 40A, 41A, 42A and 43A of the respective sprinkler heads 40, 41, 42 and 43 is presented. The sprinkler heads are corresponding with the sprinkler head SI as depicted in 20 figures 6 and 6A. On the walls 19, 20 and 21 a schematically indicated contour of the spray pattern of one sprinkler head 36 is depicted. The spray patterns of sprinkler head according to the state of the art are not sufficient for a proper wall wetting. In domestic fires, wall wetting can be 25 essential, since most wall coverings are highly flammable and tend to enhance progression of a fire.

In figure 7A a schematically indicated spray pattern 36A of a sprinkler head 36 according to the invention is presented. The walls 19, 20 and 21 are at least 30 partly reached by the approximately cone shaped spray pattern 36A. Thus the sprinkler heads according to the invention can contribute to a safer fire fighting or fire 13 retarding such that inhabitants or users can get more time to escape.

The invention is to be understood not to be limited to the exemplary embodiments shown in the figures 5 and described in the specification. For instance the grid of sprinklers may be arranged in a hexagonal or triangular arrangement.

These and other modifications are considered to be 10 variations that are part of the framework, the spirit and the scope of the invention outlined in the claims.

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List of reference signs I. Domestic sprinkler system 2 . Drinking water supply conduit 5 3. Water meter 4 . Water supply header 5. Water conduit 6. Water conduit 7. Water conduit 10 8. Boiler feed conduit 9. Boiler 10. Hot water conduit II. Cold water conduit 12A-F. Sprinkler heads 15 13. Washing machine 14. Toilet 15. Toilet 16. Water tap 17. Room 20 18A-F. Sprinkler heads 19. Wall 20. Wall 21. Wall 22. Wall 25 23. T-junction 24. Non return valve 25. Connecting conduit 26. Thread 27. Base 30 28. Bracket 29. Cap 30. Fuse 31. deflector plate 15 32 . Fixation screw 33. Cement 34. Orifice 35. Collector 5 36. Sprinkler head 36A. Spray pattern 36B. Spray contour 37. Sprinkler head 38. Sprinkler head 10 39. Sprinkler head 40. Sprinkler head 40A. Spray pattern 41. Sprinkler head 41A. Spray pattern 15 42. Sprinkler head 42A. Spray pattern 43. Sprinkler head 43A. Spray pattern 44. Ring 20 45. Pin I. Group II. Group III. Group a. Angle 25 A. Distance B. Distance C. Distance D. Distance X. Diameter 30 T. Data point 51. Data point 52. Data point 53. Data point

Claims (10)

A sprinkler head suitable for use in a drinking water pipe, the sprinkler head comprising a K factor that is lower than around 3, preferably lower than a K factor of around 2.5. A sprinkler head according to claim 1, wherein the nozzle diameter is less than 8 mm, preferably less than 7 mm. 3. A sprinkler head according to any one of the preceding claims, wherein the nozzle diameter is a maximum of 6.1 mm. A sprinkler system comprising at least one sprinkler head as claimed in claims 1 to 3. A sprinkler system according to claim 4, wherein the sprinkler heads are mounted in the vicinity of a ceiling and wall-center line distance of between approximately 500 mm and approximately 1250 mm and a mutual center line distance of adjacent sprinkler heads of approximately 1500 mm to approximately 2500 mm include. 6. A sprinkler system as claimed in claim 5, wherein a distribution channel of the sprinkler system is connected directly to the main drinking water line entering the building in which the sprinkler system is installed. 7. A sprinkler system according to any of claims 4 to 6, wherein at least one group of sprinkler heads with at least one sprinkler head mounted on the group pipe, the group pipe being connected at its first end to the drinking water supply and at its second end to a water supply, such as a washing machine, a water tap, a toilet, a shower, a boiler, a dishwasher, a garden water system and / or any other water supply is connected. 10 8. A sprinkler system according to any one of claims 4 to 7, wherein the sprinkler heads within a space comprise a first center line distance of neighboring sprinkler heads of between approximately 1500 mm and 2500 mm. 9. a sprinkler system according to any of claims 4 to 8, wherein a one-way valve is arranged in at least one sprinkler head supply line, near the branch line branch. 10. a method for installing a sprinkler system according to any of claims 4 to 9, wherein the method comprises the following steps to be carried out in suitable order: a) connecting a first end of a water pipe to a domestic drinking water supply ; b) branching the water line to a first end of a sprinkler head water supply line and connecting a sprinkler head according to claim 1 to a second end of the sprinkler head water supply line; c) arranging a water drain at a second end of the water pipe, so that the water pipe can be regularly flushed with water, wherein the water drain is a tap, a shower, a washing machine, a dishwasher, a garden water device, a boiler, a toilet and / or any other water-collecting device.