Description PIPE COUPLING DEVICE FOR USE IN SPRINKLER HEAD

Technical Field

[1] The present invention relates to a pipe coupling device for use in sprinkler heads, and more particularly, to such a pipe coupling device for use in sprinkler heads, which is adapted to support a sprinkle head exposedly installed on a ceiling in the interior of a building in such a fashion as to be coupled to a water supply piping disposed inside a ceiling plate, wherein the coupling length of the pipe coupling device can be variably adjusted depending on the distance between the water supply piping and the ceiling plate in such a fashion that the pipe coupling device has compatibility in both cases where the distance between the water supply piping and the sprinkler head is defined maximally and minimally, especially, when the distance between the water supply piping and the sprinkler head is defined minimally, the extended length of the pipe coupling device can be increased maximally while maximally reducing the entire length thereof, thereby ensuring compatibility even when the distance between the water supply piping and the sprinkler head is defined variously. Background Art

[2] Sprinklers are required by a law to be installed in high-rise buildings, high-rise apartments, theaters, departments, and the like in terms of advantages of initial extinguishment. Basic requisites for these sprinklers are regulated in Standard Nos. KSBISO6182-1 to KSBISO6182-10 of Korean Industrial Standards (KS). Also, the sprinklers may be classified into various types according to types of heat responsive elements, types of water spray dispersion, installation locations, sensitivity characteristics, and specific applications. The sprinkler may basically include a heat responsive element for sensing heat installed therein, and may be designed such that the heat responsive element is automatically operated at a predetermined temperature to cause a fire hydrant outlet (orifice) to be opened, and a certain amount of water is automatically discharged in a predetermined water spray type.

[3] Korean Utility Model Registration Publication No. 79-241 entitled "attachment device of a sprinkler head" may disclose an attachment device of a sprinkler head with a count type water supply pipe attached thereon. In this instance, the count type water supply pipe includes an outer barrel having a threaded portion formed on an inner peripheral surface thereof, and an inner barrel having a threaded portion formed on an outer peripheral surface thereof, between a water supply main pipe and a sprinkler head, so that the inner barrel is inserted into the outer barrel in a water-tight manner, and is movable within the outer barrel by thread-engagement of the thread portion.

[4] Also, Japanese Patent Laid-Open Publication Hei No. 4-329969 entitled "Joint for sprinkler head" may disclose a joint including a second cylindrical member insertedly coupled to a first cylindrical member. In this instance, the second cylindrical member includes an O-ring interposed between the first and second cylindrical members, so that the second cylindrical member is slidingly moved on the first cylindrical member, thereby adjusting a coupling height therebetween.

[5] Also, Japanese Patent Laid-Open Publication Hei No. 5-15614 entitled "branch joint for a sprinkler" proposes a branch joint for a sprinkler in which a branch joint for a sprinkler head is mounted on a discharge portion of a water supply main pipe, and a water supply pipe is mounted on a branch portion of the branch joint so as to be screw- connected with the branch joint and to be vertically movable. In this instance, the water supply pipe includes a rotational inserting/coupling portion formed thereon, so that the position of the water supply pipe can be adjusted using a rotating tool insertedly coupled to the rotational inserting/coupling portion.

[6] Also, Korean Patent registration No. 10-0705046 entitled "sprinkler connector" disclose a sprinkler connector mounted between a T-type or L-type connection pipe mounted on a water supply steel pipe for fire extinguishing horizontally installed on a ceiling of a building structure and a sprinkler head, so that the sprinkler connector is adjusted to conform to a height between the connection pipe and a board of the ceiling of the building structure. In this instance, the sprinkler connector includes a body screw-fixed to the connection pipe, a reducer vertically ascending/descending with respect to the body to correspond to a height of the ceiling and having a lower end portion to which the sprinkler head is screw-fixed, and a plurality of packings for preventing supply water from being leaked when expanding and contracting the reducer with respect to the body.

[7] Also, Korean Utility Model Registration No. 20-0410594 entitled "height-adjusting device for a fire-fighting piping" proposes a height-adjusting device for use in sprinklers in which a sliding portion and a threaded portion formed on a nipple are vertically movable along a guide groove formed on a bracket, and an adjustment member mounted within the bracket is rotated along a contact surface formed on a nipple screw portion by rotating the adjustment member, so that the nipple is vertically moved with respect to the bracket.

[8] The above-mentioned techniques proposes a pipe coupling device that enables the sprinkler head to be installed on the ceiling in such a manner as to be coupled to the water supply piping. Accordingly, the length of a pipe coupling device may be increased or reduced depending on a distance between the sprinkler head and the water supply piping.

[9] However, the above-mentioned pipe coupling device for use in a sprinkler head

according to the prior art enables its length to be increased or decreased, however, basically focuses on a maximum extendable length. As a result, there arises a problem in that a pipe coupling device having a reduced length is required to be separately manufactured when an allowable height inside a ceiling plate in which the pipe coupling device is mounted is relatively low.

[10] As shown in FIG. 1, a pipe coupling device for use in sprinkler heads may be installed in a service space (S) between a slab and a ceiling plate 6, and an actual allowable height of the pipe coupling device may be a distance (L) between a distal end of a water supply piping 1 and the ceiling plate 6. In this instance, the interfloor height in multi-family houses such as apartments may act as an important factor in construction. As customer's demands for interfloor noise proof increase, the height of the slab accordingly increases, and thus there is a need for maximum reduction of the service space (S). Accordingly, the distance (L) between the ceiling plate 6 and the water supply piping 1 required for installing the pipe coupling device may be continuously reduced. The pipe coupling device according to the prior art may have a problem in that a separate product different from a product applicable to a relatively high service space (L) is required to be manufactured in order to satisfy the above- mentioned conditions. In addition, the distance (L) between the ceiling plate 6 and the water supply piping 1 corresponds to a distance from the distal end of a connection pipe 3 such as the T-type pipe or L-type pipe coupled with a main pipe 2 to the ceiling plate 6, so that the height by which the pipe coupling device of the sprinkler head is installed is reduced, and the distance (L) is further reduced in a case where a sprinkler head 8 is inserted into the pipe coupling device.

[11] As described above, the pipe coupling device for use in the sprinkler heads according to the prior art has a problem in that a length of the pipe coupling device is required to be cut or a separate product is required to be manufactured when the distance (L) between the ceiling plate 6 and the water supply piping 1 is relatively small. Also, a method using the pipe coupling device for use in sprinkler heads is relatively complex in comparison with a general piping connecting method, and the number of constituent elements of the pipe coupling device may increase. Also, since a structure for effectively fixing the constituent elements is not provided, a separate countermeasure (sealing work) for preventing leakage of water during the piping working is needed. Disclosure of Invention Technical Problem

[12] Accordingly, the present invention has been made in an effort to solve the above problem occurring in the prior art, and it is an object of the present invention to provide a novel pipe coupling device for use in sprinkler heads wherein the coupling

length of the pipe coupling device can be variably adjusted depending on the distance between the water supply piping and the ceiling plate in such a fashion that the pipe coupling device has compatibility in both cases where the distance between the water supply piping and the sprinkler head is defined maximally and minimally, thereby ensuring compatibility even when the distance between the water supply piping and the sprinkler head is defined variously.

[13] Another object of the present invention is to provide a novel pipe coupling device for use in sprinkler heads, which can be applied to the case where when the distance between the water supply piping and the sprinkler head is defined minimally, the extended length of the pipe coupling device can be extended as long as possible while maximally reducing the entire length thereof, so that the height of a service space between the slab and the ceiling plate is reduced so as to decrease the interfloor height in multi-family houses such as apartments.

[14] Yet another object of the present invention is to provide a novel pipe coupling device for use in sprinkler heads, which can be assembled through a relative simple configuration such as a general piping connecting structure and can prevent leakage of water through only the fastening of respective constituent elements. Technical Solution

[15] To accomplish the above object, according to the present invention, there is provided a pipe coupling device for use in sprinkler heads, the pipe coupling device being adapted to support a sprinkler head 8 in such a fashion as to be coupled to a water supply piping 1 disposed inside a ceiling plate 6, including: an outer barrel 20 coupled to a water supply piping 1 ; and an inner barrel 40 insertedly coupled to the outer barrel 20 in such a fashion as to be vertically movable in a state where the inner barrel 40 has been coupled to the outer barrel 20 so as to allow a sprinkler head 8 to be coupled to a lower portion of the inner barrel so that water supplied through the water supply piping 1 is supplied to the sprinkler head 8, wherein the outer barrel 20 includes: a retaining section 22 positioned on the inner periphery of the lower end of the outer barrel 20, the retaining section having an inner diameter smaller that an outer diameter of an inner peripheral surface 24 of the outer barrel which defines the hollow space 21 vertically penetrating through the inside of the outer barrel 20 and being formed with threads; a piping-fastening section 28 positioned on the outer periphery of an upper portion of the outer barrel 20, the piping-fastening section being formed with threads so that it is inserted into the water supply piping 1 so as to be thread-engaged with the water supply piping 1 ; and a first tool engagement section 30 formed on the outer periphery of a lower portion of the outer barrel 20 and adapted to allow a tool used upon the fastening of the piping-fastening section 28 to the water supply piping 1 to be engaged

therewith, and wherein the inner barrel 30 includes: a head- fastening section 42 positioned on the inner periphery of the lower end of the inner barrel 40 and formed with threads so as to allow the sprinkler head 8 to be engagingly inserted into the lower end portion of the hollow pace 21 vertically penetrating through the inside of the inner barrel 40; a head section 60 positioned on the outer periphery of an upper portion of the inner barrel 40, and having an outer diameter which is smaller than an inner diameter of the outer barrel 20 and is greater than an inner diameter of the retaining section 22 of the outer barrel 20 so as to be downwardly inserted into the hollow space 21 of the outer barrel 20 and retained by the retaining section 22, thereby stopping the downward movement of the inner barrel 40 through the outer barrel 20; an O-ring 64 engagingly fitted around the outer periphery of the head section 60 in such a fashion as to be interposed between the inner periphery of the outer barrel 20 and the head section 60 of the inner barrel 40; a position-adjusting section 46 extending downwardly from the outer periphery of the head section 60 and being formed with threads so as to be thread-engaged with the retaining section 22 of the outer barrel 20; a stop ring 52 engagingly fitted around the outer periphery of the lower portion of the inner barrel 40 in such a fashion as to be positioned at the lower end of the position-adjusting section 46 so as to be retained by the bottom end of the outer barrel 20, thereby stopping the upward movement of the inner barrel 40 through the outer barrel 20; and a second tool engagement section 48 formed on the outer periphery of the lower portion of the inner barrel 40 in such a fashion as to be positioned below the stop ring 52 and adapted to allow a tool used upon the vertical movement of the position-adjusting section 46 along the inner periphery of the retaining section 22 of the outer barrel 20 to be engaged therewith.

[16] In the pipe coupling device for use in sprinkler heads according to the present invention, the outer barrel 20 may further include an extension section 26 extending upwardly from the piping-fastening section 28 and having an outer diameter smaller than an inner diameter of the water supply piping 1 so as to be inserted into the water supply piping 1.

[17] In the pipe coupling device for use in sprinkler heads according to the present invention, the inner barrel 20 may further include a third tool engagement section 44 positioned on the inner periphery of the upper portion thereof so as to allow a tool used upon the downward coupling of the inner barrel 40 to the outer barrel 20 to be engaged therewith.

Advantageous Effects

[18] As described above, according to the pipe coupling device for use in sprinkler heads of the present invention, the pipe coupling device can be easily applied to the case

where when the distance between the water supply piping 1 and the sprinkler head 8 is defined minimally, the height of a service space between the slab and the ceiling plate is reduced so that the whole coupling length of the pipe coupling device and the waters supply piping/the sprinkler head is reduced to decrease the interfloor height in multi- family houses such as apartments. In addition, the pipe coupling device is configure in such a fashion as to be vertically movable in a state where the inner barrel 40 is coupled to the outer barrel 20 and to extend maximally its extended length while preventing the inner barrel 40 from escaping from the outer barrel 20, so that the coupling length of the pipe coupling device can be variably adjusted depending on the distance between the water supply piping and the ceiling plate by making its extended length as long as possible, thereby ensuring compatibility even when the distance between the water supply piping and the sprinkler head is defined variously. Further, since the outer barrel 20 is formed with the first tool engagement section 30, and the inner barrel 40 is formed with the second tool engagement section 48 and the third tool engagement section 44, it is possible to conveniently perform the piping work such as the case where the outer barrel 20 and the inner barrel 40 are coupled to each other, the case where the outer barrel 20 is fastened to the water supply piping 1, the case where the position of the inner barrel 40 is adjusted minutely, etc. Moreover, since stable water-tightness is ensured, the assembly of the pipe coupling device is carried out conveniently, and the number of the whole constituent elements serving to vary the use height of the pipe coupling device is reduced relatively as compared to the conventional prior art, the pipe coupling device can be assembled through a relative simple configuration such as a general piping connecting structure and can prevent leakage of water through only the fastening of respective constituent elements. Brief Description of Drawings

[19] FIG. 1 is a schematic view illustrating the requirements of a pipe coupling device for use in sprinkler heads

[20] FIG. 2 is an exploded cross-sectional view illustrating a pipe coupling device for use in sprinkler heads according to a preferred embodiment of the present invention;

[21] FIG. 3 is an exploded perspective view illustrating a pipe coupling device for use in sprinkler heads shown in FIG. 2;

[22] FIG. 4 is a partially cut perspective view illustrating a pipe coupling device for use in sprinkler heads a state where it is set to have a minimum length according to a preferred embodiment of the present invention;

[23] FIG. 5 is a partially cut perspective view illustrating a pipe coupling device for use in sprinkler heads a state where it is set to have a maximum length according to a preferred embodiment of the present invention;

[24] FIG. 6 is a cross-sectional view illustrating a pipe coupling device for use in sprinkler heads a state where it is mounted to a water supply piping with it set to have a minimum length according to a preferred embodiment of the present invention;

[25] FIG. 7 is a cross-sectional view illustrating a pipe coupling device for use in sprinkler heads a state where it is mounted to a water supply piping with it set to have a maximum length according to a preferred embodiment of the present invention;

[26] FIGs. 8 and 9 are exploded perspective views illustrating other examples of a first tool engagement section of a pipe coupling device for use in sprinkler heads according to a preferred embodiment of the present invention;

[27] FIG. 10 is a cross-sectional view illustrating a third tool engagement section of a pipe coupling device for use in sprinkler heads according to a preferred embodiment of the present invention; and

[28] FIG. 11 is an exploded perspective view illustrating a state where a sprinkler head is serially coupled to a pipe coupling device for use in sprinkler heads according to a preferred embodiment of the present invention.

[29] <Explanation on reference numerals of main elements in drawings >

[30] 1: water supply piping 2: main pipe

[31] 3: connection pipe 6: ceiling plate

[32] 8: sprinkler head 20: outer barrel

[33] 21, 41: hollow space 22: retaining section

[34] 24: inner peripheral surface

[35] 26: extension section 28: piping-fastening section

[36] 30: first tool engagement section

[37] 40: inner barrel 42: head-fastening section

[38] 44: third tool engagement section

[39] 46: position-adjusting section

[40] 48: second tool engagement section 52: stop ring

[41] 60: head section 64: O-ring

Best Mode for Carrying out the Invention

[42] A preferred embodiment of the present invention will be described hereinafter in detail with reference to FIGs. 2 to 11. In FIGs. 2 to 11, the constituent elements performing the same function are denoted by the same reference numeral. In the meantime, in the drawings, pins, holes and the like for the coupling and fixing of main elements are shown briefly or illustration thereof will be omitted. The illustration of the items will be omitted which can be typically appreciated by those skilled in the art such as the kind and properties of the sprinkler applied to the present invention, and illustration will be made centering on the elements associated with the present invention.

Particularly, although the ratio of the size between the elements is often represented somewhat differently, such a difference of representation in the drawings is a part which can be easily understood by those skilled in the art. Thus, the separate description thereof will be omitted.

[43] FIG. 2 is an exploded cross-sectional view illustrating a pipe coupling device for use in sprinkler heads according to a preferred embodiment of the present invention, FIG. 3 is an exploded perspective view illustrating a pipe coupling device for use in sprinkler heads shown in FIG. 2, FIG. 4 is a partially cut perspective view illustrating a pipe coupling device for use in sprinkler heads a state where it is set to have a minimum length according to a preferred embodiment of the present invention, FIG. 5 is a partially cut perspective view illustrating a pipe coupling device for use in sprinkler heads a state where it is set to have a maximum length according to a preferred embodiment of the present invention, FIG. 6 is a cross-sectional view illustrating a pipe coupling device for use in sprinkler heads a state where it is mounted to a water supply piping with it set to have a minimum length according to a preferred embodiment of the present invention, FIG. 7 is a cross-sectional view illustrating a pipe coupling device for use in sprinkler heads a state where it is mounted to a water supply piping with it set to have a maximum length according to a preferred embodiment of the present invention, FIGs. 8 and 9 are exploded perspective views illustrating other examples of a first tool engagement section of a pipe coupling device for use in sprinkler heads according to a preferred embodiment of the present invention, FIG. 10 is a cross-sectional view illustrating a third tool engagement section of a pipe coupling device for use in sprinkler heads according to a preferred embodiment of the present invention, and FIG. 11 is an exploded perspective view illustrating a state where a sprinkler head is serially coupled to a pipe coupling device for use in sprinkler heads according to a preferred embodiment of the present invention.

[44] Referring to FIGs. 2 to 7, a pipe coupling device 10 for use in sprinkler heads according to a preferred embodiment of the present invention includes an outer barrel 20 coupled to a water supply piping 1, an inner barrel 40 insertedly coupled to the outer barrel 20 in such a fashion as to be vertically movable in a state where the inner barrel 40 is coupled to the outer barrel 20 so as to allow a sprinkler head 8 to be coupled to a lower portion of the inner barrel so that water supplied through the water supply piping 1 is supplied to the sprinkler head 8. Thus, the pipe coupling device 10 supports the sprinkler head 8 in such a fashion as to be coupled to the water supply piping 1 disposed inside a ceiling plate 6.

[45] In this case, the outer barrel 20 includes a retaining section 22, a piping-fastening section 28 and a first tool engagement section 30. The outer barrel 20 may be formed

integrally by machining a tubular material which is cast to internally define a non- machined hollow space 21, but such an integral type outer barrel 20 can be formed by using various methods already well-known in the art.

[46] In this embodiment, the retaining section 22 of the outer barrel 20 is positioned on the inner periphery of the lower end of the outer barrel 20, and has an inner diameter smaller that an outer diameter of an inner peripheral surface 24 of the outer barrel which defines the hollow space 21 vertically penetrating through the inside of the outer barrel 20. The retaining section 22 is formed with threads. Also, the piping-fastening section 28 is positioned on the outer periphery of an upper portion of the outer barrel 20 and is formed with threads so that it is inserted into the water supply piping 1 so as to be thread-engaged with the water supply piping 1. The first tool engagement section 30 is formed on the outer periphery of a lower portion of the outer barrel 20 and allows a tool used upon the fastening of the piping-fastening section 28 to the water supply piping 1 to be engaged therewith.

[47] In this case, the threads of the piping-fastening section 28 will be formed to conform to the shape and dimension corresponding to the standard of the connection pipe 3 positioned at a distal end of the water supply piping 1 applied typically. For example, in this embodiment, there is shown an example in which a parallel thread is applied. The threads of the piping-fastening section 28 may be typically formed to correspond to the standard of the water supply piping 1, i.e., the connection pipe 3. Also, the first tool engagement section 30, as shown in FIGs. 2 to 7, can be formed in a hexagonal shape so as to use a spanner, wrench and the like as a general fastening tool. Alternatively, as shown in FIGs. 8 and 9, the first tool engagement section 30 can be formed so as to be fastened using a separate clamp.

[48] Through such a configuration, the pipe coupling device 10 for use in sprinkler heads according to the present invention is configured such that it can be vertically adjusted in its coupling position in a state where the piping-fastening section 28 is engagingly inserted into the connection pipe 3 of the water supply piping 1, as shown in FIGs. 6 and 7. Thus, it is possible to maximize the extended length of the pipe coupling device 10 while minimizing the reduced length of the pipe coupling device 10, so that the pipe coupling device 10 for use in sprinkler heads has a greater difference between a minimum installation height Ll and a maximum installation height L2 thereof within a service space S above the ceiling plate 6.

[49] In addition, since the first tool engagement section 30 allowing for the use of the tool upon the fastening of the outer barrel 20 to the water supply piping 1 is formed on the outer periphery of the outer barrel 20 itself, the outer barrel 20 is coupled to the connection pipe 3 of the water supply piping 1 and can be manipulated conveniently upon the adjustment of its position.

[50] Meanwhile, in the pipe coupling device 10 for use in sprinkler heads according to a preferred embodiment of the present invention, the outer barrel 20 includes an extension section 26 extending upwardly from the piping-fastening section 28 and having an outer diameter smaller than an inner diameter of the water supply piping 1 so as to be inserted into the water supply piping 1. The extension section 26, as shown in FIGs. 4 and 6, the inner barrel 40 is further inserted into the connection pipe 30 while maintaining the state of an O-ring 64 hermetically sealing a space between the outer barrel 20 and the inner barrel 40, so that the height Ll required to install the piping coupling device 10 for use in sprinkler heads can be further reduced.

[51] In addition, the inner barrel 40 of the pipe coupling device 10 for use in sprinkler heads according to a preferred embodiment of the present invention includes a head- fastening section 42, a head section 60, an O-ring 64, a position-adjusting section 46, a stop ring 52 and a second tool engagement section 48. The inner barrel 40 may be formed integrally by machining a tubular material which is cast to internally define a non-machined hollow space 21.

[52] In this embodiment, the head- fastening section 42 of the inner barrel 40 is positioned on the inner periphery of the lower end of the inner barrel 40 and is formed with threads so as to allow the sprinkler head 8 to be engagingly inserted into the lower end portion of the hollow pace 21 vertically penetrating through the inside of the inner barrel 40. The head section 60 is positioned on the outer periphery of an upper portion of the inner barrel 40, and has an outer diameter which is smaller than an inner diameter of the outer barrel 20 and is greater than an inner diameter of the retaining section 22 of the outer barrel 20 so as to be downwardly inserted into the hollow space 21 of the outer barrel 20 and retained by the retaining section 22, thereby stopping the downward movement of the inner barrel 40 through the outer barrel 20. The O-ring 64 is engagingly fitted around the outer periphery of the head section 60 in such a fashion as to be interposed between the inner periphery of the outer barrel 20 and the head section 60 of the inner barrel 40. The position-adjusting section 46 extends downwardly from the outer periphery of the head section 60 and is formed with threads so as to be thread-engaged with the retaining section 22 of the outer barrel 20. The stop ring 52 is engagingly fitted around the outer periphery of the lower portion of the inner barrel 40 in such a fashion as to be positioned at the lower end of the position-adjusting section 46 so as to be retained by the bottom end of the outer barrel 20, thereby stopping the upward movement of the inner barrel 40 through the outer barrel 20. The second tool engagement section 48 is formed on the outer periphery of a lower portion of the inner barrel 40 in such a fashion as to be positioned below the stop ring 52 and adapted to allow a tool used upon the vertical movement of the position-adjusting section 46 along the inner periphery of the retaining section 22 of the outer barrel 20 to

be engaged therewith.

[53] In this case, the threads of head- fastening section 42 will be formed to conform to the shape and dimension corresponding to the standard of the sprinkler head 8 applied typically. For example, in this embodiment, there is shown an example in which a pipe thread is applied. The threads of the head- fastening section 42 may be typically formed to correspond to the standard of the sprinkler head 8.

[54] In the pipe coupling device 10 for use in sprinkler heads according to this embodiment, the head section 60, the position-adjusting section 46, an O-ring receiving groove 50 and the second tool engagement section 48 are sequentially formed on the outer peripheral surface of the inner barrel 40 in a direction from the top to the bottom. In this case, the head section 60 has an O-ring receiving groove 62 formed on the outer periphery thereof so as to allow the O-ring 64 to be engaged therewith, the position-adjusting section 46 has the threads formed thereon so as to be engaged with the threads of the retaining section 22 of the outer barrel 20, and the O- ring receiving groove 50 is formed on the outer peripheral surface of the inner barrel 40 so as to allow the stop ring 52 to be engaged therewith. Through such a configuration, as shown in FIG. 2, the inner barrel 40 is coupled to the outer barrel 20 in such a fashion that the inner barrel 40 is inserted into the hollow space 12 of the outer barrel 20 from the top of the outer barrel 20 with the second tool engagement section 48 directed toward the bottom in a state where the O-ring 64 is engagingly seated in the O-ring receiving groove 62 of the head section 60, so that the threads of the position-adjusting section 46 is engaged with the threads of the retaining section 22 of the outer barrel 20 to cause the O-ring receiving groove 50 formed on the outer periphery of the lower portion of the position-adjusting section 46 to be downwardly exposed to the outside. In this state, when the stop ring 50 is engagingly seated in the O-ring receiving groove 50 formed on the outer periphery of the lower portion of the position-adjusting section 46, the basic assembly of the product is completed.

[55] The pipe coupling device 10 for use in sprinkler heads according to this embodiment is moved vertically in a state where inner barrel 40 has been coupled to the outer barrel 20. Also, the head section 60 of the inner barrel 40 is retained by the retaining section 22 of the outer barrel 20, so that the inner barrel 40 is prevented from escaping downwardly from the outer barrel 20, and the stop ring 50 prevents the inner barrel 40 from escaping upwardly from the outer barrel 20. Further, since the stopped position by the stop ring 40 allows the O-ring 64 supported against the inner wall of the outer barrel 20 to be held in position within the outer barrel 20, a worker does not need to carefully observe the fastening or unfastening height of the inner barrel 40 during the assembly, making it convenient to assemble the piping coupling device while securing more stable water-tightness.

[56] In addition, as shown in FIGs. 3 to 5, 8 and 9, the second tool engagement section 48 formed on the inner barrel of the pipe coupling device 10 for use in sprinkler heads according to this embodiment is formed in a hexagonal shape so as to use a spanner, wrench and the like as a general fastening tool, so that it enables a user to conveniently perform a piping work upon the position adjustment of the inner barrel 20 like the above-mentioned function of the first tool engagement section 30 of the outer barrel 20. Particularly, in the pipe coupling device 10 for use in sprinkler heads according to the present invention, the inner barrel 40 further includes a third tool engagement section 44 positioned on the inner periphery of the upper portion thereof so as to allow a tool used upon the downward coupling of the inner barrel 40 to the outer barrel 20 to be engaged therewith, making it convenient an initial assembly step in which the inner barrel 40 is coupled to the outer barrel 20.

[57] In the meantime, in the pipe coupling device 10 for use in sprinkler heads according to this embodiment, the sprinkler head 8 can be formed in the shape of a nipple so as to improve convenience of the assembly of the pipe coupling device.

[58] In this manner, the pipe coupling device 10 for use in sprinkler heads according to this embodiment has a merit in that the number of its constituent elements is minimized as being composed of only the inner barrel 40 having the O-ring 64 and the stop ring 52 engaged therewith and the outer barrel 20. Moreover, it is possible to maximally reduce the length of the portion of the inner barrel 40 externally exposed relative to the outer barrel 20. Thus, the pipe coupling device 10 can be easily applied to the case where when the distance between the water supply piping 1 and the sprinkler head 8 is defined minimally, the height of a service space between the slab and the ceiling plate is reduced so that the whole coupling length of the pipe coupling device and the waters supply piping/the sprinkler head is reduced to decrease the interfloor height in multi-family houses such as apartments as shown in FIG. 6. In addition, as shown in FIG. 7, the pipe coupling device 10 has an advantage in that it can be installed by extending its extended length as long as possible since it can be configured such that its extended length is increased maximally while maximally reducing the length of the pipe coupling device 10.

[59] While the pipe coupling device for use in sprinkler heads according to the present invention has been described and illustrated in connection with a specific exemplary embodiment with reference to the accompanying drawings, it will be readily appreciated by those skilled in the art that it is merely illustrative of the preferred embodiment of the present invention and various modifications and changes can be made thereto within the technical spirit and scope of the present invention. Mode for the Invention

[60] To accomplish the above object, according to the present invention, there is provided a pipe coupling device for use in sprinkler heads, the pipe coupling device being adapted to support a sprinkler head 8 in such a fashion as to be coupled to a water supply piping 1 disposed inside a ceiling plate 6, including: an outer barrel 20 coupled to a water supply piping 1 ; and an inner barrel 40 insertedly coupled to the outer barrel

20 in such a fashion as to be vertically movable in a state where the inner barrel 40 has been coupled to the outer barrel 20 so as to allow a sprinkler head 8 to be coupled to a lower portion of the inner barrel so that water supplied through the water supply piping 1 is supplied to the sprinkler head 8, wherein the outer barrel 20 includes: a retaining section 22 positioned on the inner periphery of the lower end of the outer barrel 20, the retaining section having an inner diameter smaller that an outer diameter of an inner peripheral surface 24 of the outer barrel which defines the hollow space 21 vertically penetrating through the inside of the outer barrel 20 and being formed with threads; a piping-fastening section 28 positioned on the outer periphery of an upper portion of the outer barrel 20, the piping-fastening section being formed with threads so that it is inserted into the water supply piping 1 so as to be thread-engaged with the water supply piping 1 ; and a first tool engagement section 30 formed on the outer periphery of a lower portion of the outer barrel 20 and adapted to allow a tool used upon the fastening of the piping-fastening section 28 to the water supply piping 1 to be engaged therewith, and wherein the inner barrel 30 includes: a head- fastening section 42 positioned on the inner periphery of the lower end of the inner barrel 40 and formed with threads so as to allow the sprinkler head 8 to be engagingly inserted into the lower end portion of the hollow pace 21 vertically penetrating through the inside of the inner barrel 40; a head section 60 positioned on the outer periphery of an upper portion of the inner barrel 40, and having an outer diameter which is smaller than an inner diameter of the outer barrel 20 and is greater than an inner diameter of the retaining section 22 of the outer barrel 20 so as to be downwardly inserted into the hollow space

21 of the outer barrel 20 and retained by the retaining section 22, thereby stopping the downward movement of the inner barrel 40 through the outer barrel 20; an O-ring 64 engagingly fitted around the outer periphery of the head section 60 in such a fashion as to be interposed between the inner periphery of the outer barrel 20 and the head section 60 of the inner barrel 40; a position-adjusting section 46 extending downwardly from the outer periphery of the head section 60 and being formed with threads so as to be thread-engaged with the retaining section 22 of the outer barrel 20; a stop ring 52 engagingly fitted around the outer periphery of the lower portion of the inner barrel 40 in such a fashion as to be positioned at the lower end of the position-adjusting section 46 so as to be retained by the bottom end of the outer barrel 20, thereby stopping the upward movement of the inner barrel 40 through the outer barrel 20; and a second tool

engagement section 48 formed on the outer periphery of the lower portion of the inner barrel 40 in such a fashion as to be positioned below the stop ring 52 and adapted to allow a tool used upon the vertical movement of the position-adjusting section 46 along the inner periphery of the retaining section 22 of the outer barrel 20 to be engaged therewith.

[61] In the pipe coupling device for use in sprinkler heads according to the present invention, the outer barrel 20 may further include an extension section 26 extending upwardly from the piping-fastening section 28 and having an outer diameter smaller than an inner diameter of the water supply piping 1 so as to be inserted into the water supply piping 1.

[62] In the pipe coupling device for use in sprinkler heads according to the present invention, the inner barrel 20 may further include a third tool engagement section 44 positioned on the inner periphery of the upper portion thereof so as to allow a tool used upon the downward coupling of the inner barrel 40 to the outer barrel 20 to be engaged therewith.

Industrial Applicability

[63] The pipe coupling device for use in sprinkler heads according to the present invention is adapted to support a sprinkle head exposedly installed on a ceiling in the interior of a building in such a fashion as to be coupled to a water supply piping disposed inside a ceiling plate. The coupling length of the pipe coupling device can be variably adjusted depending on the distance between the water supply piping and the ceiling plate in such a fashion that the pipe coupling device has compatibility in both cases where the distance between the water supply piping and the sprinkler head is defined maximally and minimally. Especially, when the distance between the water supply piping and the sprinkler head is defined minimally, the extended length of the pipe coupling device can be increased maximally while maximally reducing the entire length thereof, thereby ensuring compatibility even when the distance between the water supply piping and the sprinkler head is defined variously.