GB2123689A

GB2123689A - Longitudinally adjustable dry sprinkler head

Info

Publication number: GB2123689A
Application number: GB08316874A
Authority: GB
Inventors: Wilfried Klein
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-06-22
Filing date: 1983-06-21
Publication date: 1984-02-08
Also published as: GB2123689B; GB8316874D0; DE3223154A1

Abstract

A dry sprinkler head is described that can be longitudinally adjusted over a wide range without detriment to its seal and hence adjusted to particular on-site conditions when installed in a fire-control sprinkler system. It includes the conventional activating and sealing components, which are, however, positioned at a certain distance from each other in an assembly of pipes that contains a mechanism that transmits the action of the activating component to the sealing component. The overall length of the assembly can be continuously varied to adjust to on-site conditions and the mechanism will adapt to a particular length. <IMAGE>

Description

SPECIFICATION Longitudinally adjustable dry sprinkler head The invention concerns a longitudinally adjustable dry sprinkler head.

Automatic fire-control sprinkler systems that employ water as a quenching medium are designed on the dry-head principle when the pipes are exposed to freezing. In accordance with this principle the pipes are filled with air under a slight excess pressure and the water does not flow into and fill the pipes until one of the sprinkler heads responds to the heat of a fire and opens an appropriate valve.

If the sprinkler heads are suspended from the pipes, not only each head but also the riser between it and the horizontal pipes must be kept clear of water to prevent the system as a whole from freezing up. This can be done with dry-head sprinkler systems.

To provide a reliable seal between the heads and the water-supply pipes while ensuring that the sprinklers will activate at precisely the right time in the event of a fire, the sealing and activating components of known dry sprinkler heads are mounted at a certain distance apart, the former at the end that leads to the supply pipes and the latter at the free end that leads into the environment. Various systems are known in which the activating component operates in conjunction with the sealing component to place the latter in direct communication with the water-supply pipes in the event of fire so that the water or air can flow out unimpeded.Dry sprinkler heads of known design accordingly accommodate a transmission mechanism, a spring for example, that is positioned between the two components and has enough resilience to open the sealing component when the activating component responds to the heat, releasing the water.

Completely filling the riser between the sprinkler head and the supply pipes with a frostresistant liquid that flows out and opens a sealing component when the the activating component responds is also known.

Such sprinkler systems entail certain drawbacks, especially with respect to installation.

The slope of the supply pipes that lead to the sprinkler heads makes it necessary to adjust the length of each head individually to the particular local conditions if each is to extend from the ceiling in the correct position and at the correct height, which is one of the conditions for effective operation. The unevenness of the ceiling, especially of a suspended ceiling, also causes problems in this respect. To position the heads as accurately as possible the overall length of each must be individually measured and cut at the factory before it is mounted in its prescribed position. This is expensive.

Dry-head sprinklers in which the riser is mounted in an adjustable rose (or facing) are also known. This design however allows the length of the head to be varied only to a very limited extent.

Suspending dry sprinkler heads in such a way that they can inserted in what is called a dome next to the sprinkler pipe and held in place with specially designed fittings has also been proposed.

Since the head itself can not be adjusted longitudinally in such a system, however, only very limited adjustments can be made during installation.

The object of the present invention is therefore to provide a dry sprinkler head that can be adjusted longitudinally to a greater extent and directly adapted to varying local conditions when mounted in a sprinkler system. A dry sprinkler head in accordance with the invention is characterized by an assembly of mutually adjustable pipes that is variable in overall length and accommodates a mechanism that automatically adapts to a particular length and transmits the action of the activating component of the head to the sealing component.

Certain elements of the assembly of pipes preferably slide telescopically into or are screwed into others.

A dry sprinkler head in accordance with the invention will be especially easy to position and mount if the elements of the assembly of pipes can be adjusted from outside and the transmission mechanism is located inside it.

Because it is designed as an assembly of pipes, the length of a dry sprinkler head in accordance with the invention can be adjusted over a wide range. If, for example, the assembly is made up of two equally long pipes one inside the other, the head can be extended from a length at which one pipe is completely inside the other to a length at which it projects almost completely out of the other, a ratio of almost 2:1. The mechanism that is mounted inside a dry sprinkler head in accordance with the invention, that automatically adapts to a particular length, and that transmits the action of the activating component of the head to the sealing component ensures that these components will operate in conjunction when the head is mounted in place no matter where.

The dry sprinkler head in accordance with the invention eliminates the necessity of measuring the individual installed dimensions of the heads on site and then cutting them to fit. Rather, only one model is as a rule necessary, because the longitudinal variability of each head makes it possible to adapt it on the spot to the wide variety of installation conditions that prevail there by simply sliding the elements of the assembly one inside the other.

The invention will now be specified with reference to the drawings, in which Figure 1 is a section through one embodiment of a dry sprinkler head in accordance with the invention connected to a water-supply system and in the sealing state, Figure 2 is a section through another embodiment of a dry sprinkler head connected to a water-supply system and in the sealing state, and Figure 3 is a section through a third embodiment of a dry sprinkler head connected to a water-supply system and in the sealing state.

Figure 1 illustrates a dry sprinkler head 1 in accordance with the invention that is connected to water-supply system 2 by a T connector 3. Watersupply system 2 consists of pipes 4 that are hung parallel and across each other and connected. They transport the quenching medium. Pipes 4 are mounted for example in a ceiling and all of them preferably slope to facilitate the release of the quenching medium when necessary. The pipes conventionally slope at an angle ranging between 0.2 and 1 cm/m from the horizontal.

A tubular fitting 6 with a bottom, outwardly flanged edge 7 extends from dry sprinkler head 1 up into T connector 3. Fitting 6 is appropriately fastened, by welding or screwing for example, into T connector 3, preferably so that it can be disconnected but in any case securely enough to ensure tightness between the tubular shaft 5 of T-connector 3 and fitting 6 on dry sprinkler head 1, a tightness that is reinforced by appropriate packing.

Fitting 6 is long enough to extend flush with pipe 4 and a central hole 9 is bored through the face 8 of the fitting adjacent to the pipe.

An outside telescoping pipe 1 5 extends down from the outer surface of the flanged edge 7 of fitting 6, to which it is rigidly attached, by welding, cementing, or screwing for example. At the bottom, which is free, of outside telescoping pipe 1 5 is an inward-facing shoulder 1 6 to which is attached a tapering tubular end 1 7. The threaded outer circumference 1 8 of end 1 7 parallels outside telescoping pipe 1 5 and the top 20 of its inside surface 19 also parallels pipe 1 5 although its bottom 21 slopes out. A threaded cap 22 is screwed onto the outer circumference 1 8 of tubular end 17.The bottom part 23 of threaded cap 22 is displaced inward and its interior surface 24 is essentially a mirror image of the inside surface 19 of end 17. The bottom part 23 of threaded cap 22 has a conical, inwardly sloping section 25 to which is connected a lower section 26 that parallels outside telescoping pipe 1 5. The surfaces of top 20 and lower section 26 merge into each other and the surfaces of bottom 21 and section 25 form an annular space 27.

Another, inside, telescoping pipe 30 is mounted in the space formed by the surfaces of top 20 and lower section 26 and in direct contact with them.

Inside telescoping pipe 30 is held in place with a locking ring 31 in annular space 27. Locking ring 31 can be made of rubber or other material that is appropriate for retaining inside telescoping pipe 30 in place by friction. Inside telescoping pipe 30 is slightly shorter than outside telescoping pipe 15, extending, when it is in a position in which its bottom is about even with the lower edge of threaded cap 22, into the vicinity of the flanged edge 7 of fitting 6.

A lower sealing piece 32 with an invertedconical hole 33 bores through its axis fits tightly into inside telescoping pipe 30. The bottom end 34 of hole 33 is cylindrical and the bottom of sealing piece 32 has a flanged edge 35.

A rod 36 with a mount at it3 bottom, which is free, for the bulb that forms the activating component 38 of dry sprinkler head 1 extends through hole 33 along the axis of telescoping pipes 1 5 and 30. The mount can be called a bulb rider 37 in general terms and its function will be described later in detail. The cross-section of bulb rider 37 is more or less trapezoidal and it lies tightly against the inside surface of the cylindrical bottom end 34 of hole 33. A glass bulb, activating component 38, extends from bulb rider 37 to a deflector 39 that is mounted in a frame 40 that fits into the flanged edge 35 of sealing piece 32.

The bottom of bulb rider 37 has a sealing plate 41 that is iarger than the passage through the bottom end 34 of hole 33, limiting the potential upward travel of bulb rider 37 and rod 36.

Rod 36 extends along the axis of inside telescoping pipe 30 to its top where it bends twice, outward and upward. At the upper, free, end of rod 36 is a shaft 45 that is perpendicular to it and extends through a vertical slot 46 through inside telescoping pipe 30. There is a pulley 47 on the free end of shaft 45. There is another pulley 48 at a certain distance from pulley 47 that has a shaft 49 that is rigidly attached to inside telescoping pipe 30. Above pulley 48 and at a certain distance from it is a third pulley 50 that has a shaft 51 that is rigidly attached to fitting 6.

A cable 52, the bottom of which is fixed in place at the bottom of outside telescoping pipe 1 5, runs around pulleys 47, 48, and 50 as illustrated in Figure 1 and its upper end, after reversing around pulley 50, is attached to a sealing component 53. An arm 54 extends up from the bottom of sealing component 53 to a sealing plug 55 that extends through and fits tightly into the hole 9 bored through the face of fitting 6. Sealing plug 55 is shaped essentially like a truncated cone. It has a plate 56 at the bottom that rests against an outward slope 10 below face 8 and limits the potential upward travel of sealing component 53 into pipe 4.

The function of the dry sprinkler head illustrated in Figure 1 will now be specified.

Dry sprinkler head 1 is connected to pipe 4 in water-supply system 2 by fitting 6. When threaded cap 22 is released, inside telescoping pipe 30 can be extracted downward out of outside telescoping pipe 1 5 and established in any desired position by tightening threaded cap 22 and tensioning locking ring 31. The particular overall length of the dry sprinkler head will depend on conditions at the site of installation. The overall length of the embodiment illustrated in Figure 1 can be almost doubled by extracting inside telescoping pipe 30. Sealing component 53 and especially sealing plug 55 will remain in the sealing position while the length of the device is being adjusted because the pulleys 47 and 48 mounted on inside telescoping pipe 30 will be carried along during the adjustment, so that the tension on cable 52 will remain constant, maintaining the pressure against sealing component 53, assuming of course that 52 is stretch tight over its total length and especially around pulleys 47, 48, and 50. A belt or chain can of course also be employed instead of a cable, in which case the pulleys can be replaced with cogwheels.

Activating component 38 will respond to a particular given temperature by bursting and falling out of frame 40, at which rod 36, which rests on bulb rider 37, will drop, drawing pulley 47 down slot 46. The tension on cable 52 will immediately be released and sealing component 53 will drop subject to gravity and free the hole 9 bored through fitting 6. The air and quenching medium in pipe 4 can now immediately penetrate into and flow through dry sprinkler head 1 and emerge at the bottom through hole 33, frame 40, and deflector 39 into the environment.

The dry sprinkler head in accordance with the invention therefore can not only be continuously adjusted over a wide range of lengths without detriment to the operation of the system but will also immediately release its seal in the event of fire, so that the quenching medium can penetrate into the head and hence into the environment.

When a ceiling equipped with a dry sprinkler system with heads in accordance with the invention must be lowered or its position otherwise altered for any reason, the existing heads can be simply and manually adapted to the new conditions by the measures described hereinabove without detriment in any way to the operation of the overall system.

Figure 2 shows another embodiment of a dry sprinkler head in accordance with the invention.

The same reference numbers are used for the parts that are the same as those in the embodiment illustrated in Figure 1. The embodiment in Figure 2 differs especially from that in Figure 1 in the mechanism that transmits the action of the activating component to the sealing component. This mechanism consists, in the present embodiment, of a bellows 60, a guide 61, and a capillary tube 62. Bellows 60 is the element that seals in the quenching medium.

Bellows of this type are usually made of copper alloys or stainless steel. One end of bellows 60 is soldered to guide 61 and its other end to connector 63. An extension 64 along the longitudinal axis of telescoping pipes 1 5 and 30 engages a hole 65 that is bored through guide 61.

Hole 65 narrows more or less in the bottom third of the guide to form a shelf 66 penetrated by a passage 67. Shelf 66 defines the lowest point to which the extension 64 in guide 61 can travel as will be explained in detail. The hole 65 through guide 61 expands again below passage 67 to form a seating for the top of capillary tube 62, which is fastened into it by appropriate means. Capillary tube 62 can be made of copper, a copper alloy, or stainless steel. It is shaped like a helical spring and extends down from the bottom of guide 61, which is immovably attached in inside telescoping pipe 30 by a mount 68 in fitting 6. Capillary tube 62 spirals along the axis of telescoping pipes 1 5 and 30 and merges into a straight section that extends through the hole 33 in sealing piece 32 and frame 40, projecting slightly beyond them.It can be soldered into frame 40 with hard solder (melting point higher than 4000C). The end 69 of capillary tube 62 that projects beyond frame 40 is sealed off with a fuse plug 70. Bellows 60, guide 61, and capillary tube 62 are full of an appropriate frostresistant fluid and the pressure of the fluid forces bellows 60, which is at its uppermost position when it extends through the hole 65 through guide 61, into hole 9, reliably sealing it off.

When the length of dry sprinkler head 1 is to be adjusted, threaded cap 22 is loosened as in the embodiment illustrated in Figure 1 and inside telescoping pipe 30 is withdrawn to the desired extent from outside telescoping pipe 1 5 and fastened in the new position with threaded cap 22 or locking ring 31. Spiral capillary tube 62 will conform elastically to the change in length without releasing sealing plug 55 from the sealing position. When the environmental temperature rises to a certain point, the fuse plug 70 on the end of capillary tube 62 will melt, releasing the compression fluid in the tube. The fluid in bellows 60 and guide 61 will also immediately flow out, bellows 60 will drop, and extension 64 will fall through the hole 65 through guide 61 until it comes to rest against shelf 66.Sealing plug 55 will also drop, uncovering the hole 9 leading to pipe 4, so that the air or quenching medium in the pipe can penetrate into dry sprinkler head 1, flow through it, and emerge at the bottom through deflector 39.

The length of this embodiment of the dry sprinkler head in accordance with the invention can also be easily adjusted over a wide range by very simple means. All operations can be easily carried out manually from outside and no special tools are necessary. The embodiment in Figure 2 can naturally be adapted at any time, like that in Figure 1 , to varying on-site conditions by changing its overall length.

Figure 3 illustrates a third embodiment of a dry sprinkler head in accordance with the invention in which the overall length can be varied by screwing inside telescoping pipe 30 into and out of outside telescoping pipe 1 5. In this embodiment a nut 80 is welded at a point 81 to the bottom end, which is free, of outside telescoping pipe 1 5, extending it. Naturally, the bottom of outside telescoping pipe 1 5 could have inside threads instead of a welded-on threaded extension. Inside telescoping pipe 30 has threads on the outside so that it can be screwed into nut 80. A sealing piece 32, essentially the same as that in Figure 1, is inserted immovably into the bottom, free, end of inside telescoping pipe 30.Hole 33 is exactly the same as the hole 33 in Figure 1 except that it also has diametrically opposing grooves that allow a center-grooved dowel pin 87 to move parallel to the axis of the telescoping pipes but not to rotate around the axis relative to the connector. A threaded rod 82 extends into hole 33. There is a bulb rider 37 similar to that in Figure 1 at the bottom of threaded rod 82. Bulb rider 37 rests on an activating component 3R that consists of a glass bulb as in Figure 1. Threaded rod 82 extends through a coaxial telescoping pipe 83. A nut 84 is welded to the bottom, which is free, of telescoping pipe 83, extending it like nut 80 at the bottom of outside telescoping pipe 1 5. Telescoping pipe 83 could also have inside threads, of course, instead of a welded-on extension.Telescoping pipe 83 extends to the sealing component of dry sprinkler head 1, which in this embodiment is not a separate tubular component. Outside telescoping pipe 1 5 itself, rather, extends into T connector 3, in which it is rigidly attached by appropriate means, welding, cementing, or threading for example. The sealing plug 55 of sealing component 53 engages the hole 9 through the face 8a of outside telescoping pipe 1 5. Sealingplug fitting 85, which extends downward in the shape of a cylinder, is inserted in the top of telescoping pipe 83. In its uppermost adjustment position, threaded rod 82 is at a slight distance from the bottom edge of fitting 85.Since nuts 80 and 84, rod 82, and inside telescoping pipe 30 are threaded at the same pitch, inside telescoping pipe 30 will travel into or out of outside telescoping pipe 1 5 through nut 80 and threaded rod 82 will simultaneously travel into or out of telescoping pipe 83 through nut 84 when sealing piece 32 is rotated. The two center-grooved dowel pins 86 and 87 between outside telescoping pipe 1 5 and telescoping pipe 83 at the top and between sealing piece 32 and threaded rod 82 prevent telescoping pipe 83 from rotating as well and transfer the torque of inside telescoping pipe 30 and sealing piece 32 to threaded rod 82, so that it will travel out of telescoping pipe 83 as inside telescoping pipe 30 is screwed in relation to outside telescoping pipe 1 5.

When the environmental temperature rises to a certain point, activating component 38 (the glass bulb) will burst as described with reference to Figure 1 and bulb rider 37 will drop, carrying threaded rod 82 and telescoping pipe 83 with it.

As this transmission mechanism 82 and 83 drops, the rider or mount at the top of telescoping pipe 83 will be withdrawn from sealing plug 55, opening hole 9. The air or quenching medium can then immediately flow out of pipe 4 into dry sprinkler head 1 and through frame 40 and deflector 39 into the environment.

The dry sprinkler head 1 illustrated in Figure 3 also completely fulfills the objective of the invention and its length can be continuously adjusted by directly screwing inside telescoping pipe 30 in or out of outside telescoping pipe 1 5.

Other embodiments of the dry sprinkler head 1 in accordance with the invention will be obvious to one skilled in the art.

Claims

1. A longitudinally adjustable dry sprinkler head comprising an activating component, a sealing component spaced certain distance from the activating component, and means connecting both components so that the distance therebetween can be adjusted, the connecting means comprising an assembly of mutually adjustable pipes that is variable in overall length and includes a mechanism that automatically adapts to a particular length and transmits the action of the head to the sealing component irrespective of the particular length.

2. A dry sprinkler head according to Claim 1, wherein the length of the assembly of pipes can be varied from outside.

3. A dry sprinkler head according to Claim 1, wherein the elements of the assembly of pipes are telescopically connected so that one can slide inside or outside another.

4. A dry sprinkler head according to Claim 1, wherein one of the assembly of pipes is threadedly connected to another so it can be screwed inside or outside the other.

5. A dry sprinkler head according to Claim 1, wherein the mechanism which transmit the action of the activating component to the sealing component is inside the assembly of pipes.

6. A dry sprinkler head according to Claim 1, wherein the transmission mechanism comprises a longitudinally displaced rod.

7. A dry sprinkler head according to Claim 1, wherein the transmission mechanism further includes a cable or belt running a series of pulleys, the pulleys being operatively connected sealing component.

8. A dry sprinkler head according to Claim 1, wherein the transmission mechanism includes a hydraulic fluid.

9. A dry sprinkler head according to Claim 1, wherein the transmission mechanism comprises a rack and pinion.

1 0. A dry sprinkler head according to Claim 1, 4 wherein the transmission mechanism comprises a telescoping pipe with inside threading and a threaded rod that is screwed in it, outside threading on the inside telescoping pipe engaging threading in the outside telescoping pipe with all the threading having the same pitch.

11. A dry sprinkler head according to Claim 10, wherein the transmission mechanism and the telescoping pipes include several components that telescopically screw into one another and have the same thread pitch.

12. A longitudinally adjustable dry sprinkler head substantially as hereinbefore described with reference to any one of Figures 1 to 3 of the accompanying drawings.