Patent Description:
The growth of the warehousing storage market has created pressure to increase not only the square footage of warehouses, but also warehouse ceiling heights and the density with which products (known as commodities) may be stored in those warehouses. Sprinklers known as early suppression fast response (ESFR) fire suppression sprinklers were developed in the <NUM> to face the fire challenges associated with warehouse storage. Sets of interrelated codes and standards, especially those promulgated by the National Fire Sprinkler Association (NFPA), UL, and FM Global set the standards for the minimum performance of ESFR sprinklers as well as for the applications in which the different ESFR sprinklers may be used depending on their individual performance. Such ESFR sprinklers are commonly classified by the amount of water they are capable of delivering at a given pressure, expressed as a "k-factor" which is defined as the relationship between the water discharge rate "Q" from a sprinkler to the water pressure "p" with in the sprinkler through the formula Q=k(p)<NUM>/<NUM>, with ESFR sprinklers having standardized k-factors of approximately <NUM>, <NUM>, and <NUM>/s/(kPa)<NUM>/<NUM> (<NUM>, <NUM>, and <NUM> gpm/(psi) <NUM>/<NUM> ) being exemplars. Higher k-factor sprinklers discharge more water at a given pressure than do smaller k-factors, therefore, higher k-factor ESFR sprinklers are used to provide protection as ceiling heights increase, and standards such as NFPA-<NUM> "Standard for the Installation of Sprinkler Systems" set forth certain maximum ceiling heights, commodity heights, and commodity spacing for use with given k-factor sprinklers.

A recent challenge to the design of ESFR sprinklers of k-factor <NUM>/s/(kPa)<NUM>/<NUM> (<NUM> gpm/(psi) <NUM>/<NUM> ) and greater (which are capable of being listed for use with ceiling heights of <NUM>' and greater) was a change to the performance criteria set forth by UL's UL1767 standard that such sprinklers demonstrate the ability to meet the demands of what is known as "high clearance" applications via a live fire test. High clearance applications refer to the protection of commodities in warehouses having a large clearance between the warehouse ceiling and the commodity. Warehouses having a ceiling height of <NUM> meters (<NUM> feet) and greater may have commodities shelved in racks at a height of <NUM> meters (<NUM> feet) from the floor, leaving a clearance of <NUM> meters (twenty feet) between the ceiling (near where the sprinklers are positioned) and the commodity. Where the clearance distance is greater than <NUM> meters (<NUM> feet), such applications are referred to as "high clearance" applications. The challenges to ESFR sprinklers operating at such high clearances include maintaining a core flow of fire suppressing liquid which has sufficient density and velocity to suppress a fire below the sprinkler itself while also maintaining an outer surrounding "umbrella" spray pattern to provide the required disbursement to protect the desired area, as well as sufficient flow in an intermediate range between the outer umbrella pattern and the core flow to prevent a fire in that intermediate zone from growing and overwhelming the outer umbrella. However, for some prior art ESFR sprinkler designs, a high clearance distance between the sprinkler and the commodity allows the spray pattern to become disbursed over too large an area, thereby reducing the spray pattern density, especially in the intermediate zone, and hence the sprinkler's fire suppression effectiveness. Such conditions may also allow updrafts created by thefire plume to disrupt and lift the outer umbrella spray pattern, which in some cases causes wetting and cooling of adjacent sprinklers, thereby preventing or delaying their operation. This phenomenon is known as "skipping" because the fire's heat plume "skips" the nearby cooled sprinklers which are otherwise best placed to suppress the fire. Furthermore, skipping also tends to permit the triggering of sprinklers that are more remote from the fire, and thus less effective at fire suppression. The result is an increase in both fire and water damage as well as additional risk to firefighters called to fight the blaze, as skipping may ultimately result in the fire protection system being overwhelmed.

In addition to the regulations which control the ceiling height and the height of the commodity shelved in racks below the ceiling at each given sprinkler k-factor, these regulations further set forth certain minimum clearance distances between the racks which store the commodity (known as the aisle width). These regulations exist because the demands on a system of ESFR sprinklers is affected not only by the maximum height at which a commodity is stored, but also by the number of racks of the commodity stored below any given grid of ESFR sprinklers. The minimum aisle width standards thus act in concert with the rack height standards as a limit on the amount of commodity which can be stored in a given area, while requiring clearance between the racks for the water plume from the sprinklers to travel unimpeded by the racks to reach the source of the fire as well as to wet adjacent racks of commodity to prevent ignition jumping from one rack to another. Smaller minimum aisle widths thus represent increasing demands on the performance of ESFR sprinklers as well as offering increased density of commodity storage at any given maximum storage height. Conversely, ESFR sprinklers which can exceed the minimum testing criteria necessary to achieve approvals for use at standard aisle widths, and which are approved for use at aisle widths less than the standard minimum aisle widths (known as Specific Application approvals) can be seen as having demonstrated improved performance which can improve fire suppression even at standard aisle widths.

The design of high k-factor ESFR sprinklers is therefore challenged not only by the need to pass the minimum performance criteria for such sprinklers, such that the sprinkler may be marketed as listed or approved for the default applications, but also by the desire to have performance that exceeds those minimum criteria in order to obtain Special Application approvals for use in a greater range of applications, especially those which permit a greater density storage of the commodity at smaller aisle widths than the minimum performance criteria in NFPA <NUM> allows. Such high performance ESFR sprinklers may be expected to provide improved protection even at standard storage densities and aisle widths.

There is clearly an opportunity to improve fire suppression sprinklers, particularly ESFR type sprinklers, to handle the challenges of high clearance warehouse fire protection and offer improved performance, including through demonstrating an ability to tolerate an increase the density at which commodities may be stored. <CIT> relates to a fire protection sprinkler as defined in the preamble part of independent claim <NUM> as appended.

The present invention is defined by independent claim <NUM> as appended. The invention concerns fire suppression sprinklers. In an example embodiment, the sprinkler comprises a body surrounding a bore. The bore defines a flow axis arranged coaxially with the bore. First and second frame arms are mounted on opposite sides of the body and extend therefrom in a direction along the flow axis. The frame arms define a plane. A nose is mounted on the ends of the frame arms. The nose is positioned coaxially with the flow axis. A deflector plate is mounted on the nose and is oriented transversely to the flow axis. The deflector plate has a periphery surrounding a center located on the flow axis. In an example embodiment the deflector plate comprises a plurality of slots of a first configuration extending from the periphery radially toward the center. At least two of the slots of the first configuration are disposed in the plane. At least four slots of a second configuration extend from the periphery radially toward the center and are located about the periphery such that one of the slots of the second configuration is positioned adjacent to each side of each of the slots of the first configuration which are disposed in the plane. A plurality of slots of a third configuration extend from the periphery radially toward the center. The slots of the second configuration have a greater area than the slots of the first configuration.

In an example embodiment, the slots of the second configuration have the greatest area of any of the slots of the first and the third configurations. Further by way of example, the bore defines a k factor of k=<NUM>/s/(kPa)<NUM>/<NUM> (k=<NUM> gpm/ (psi)<NUM>/<NUM>) or greater and the fire suppression sprinkler is adapted to be installed in a pendent orientation. In an example embodiment the slots of the second configuration have a club shape comprising a handle extending from the periphery and a club head terminating at a distance from the center. A width of the club head proximate to the handle is less than a width of the club head proximate to the center. In an example, a widest width of the club head is wider than a widest width of the handle. Further by way of example, the club head has a curved tip at the distance from the center. In another example embodiment, the club head is asymmetric with respect to a line extending radially from the center. In a further example, the club head is defined by a first edge oriented at a first angle with respect to the line, and a second edge, opposite to the first edge, the second edge oriented at a second angle with respect to the line, the second angle being different from the first angle.

In an example embodiment, each of the slots of the second configuration are symmetric with respect to a line extending radially from the center. Further by way of example, the slots of the second configuration have a keyhole shape comprising a waist extending from the periphery and a key head terminating at a distance from the center. In an example, a widest width of the key head is wider than a widest width of the waist. In a further example, a width of the key head proximate to the waist is equal to a width of the key head proximate to the center. In an example embodiment, the key head has a curved tip at the distance from the center. Further by way of example, the key head is symmetric with respect to a line extending radially from the center.

In an example embodiment, the slots of the first configuration have an arrowhead shape comprising a shaft extending from the periphery and an arrowhead terminating at a first distance from the center. The arrowhead is asymmetric with respect to a line extending radially from the center in this example. In an example embodiment the arrowhead is defined by a first edge oriented at a first angle with respect to the line, and a second edge, opposite to the first edge. The second edge is oriented at a second angle with respect to the line and the second angle is different from the first angle. By way of example, a widest width of the arrowhead is wider than a widest width of the shaft. In an example, a width of the arrowhead proximate to the shaft is greater than a width of the arrowhead proximate to the center. Further by way of example, the arrowhead has a curved tip at the distance from the center. In another example, the shaft has a width at the periphery which is greater than a width of the shaft proximate to the arrowhead. In an example embodiment the shaft is defined by first and second oppositely disposed edges. Each edge is angularly oriented with respect to a line extending radially from the center such that the shaft has a width at the periphery which is greater than a width of the shaft proximate to the arrowhead.

In a further example embodiment, the deflector plate comprises a plurality of slots of a fourth configuration. By way again of example, the deflector plate further comprises a plurality of slots of a fifth configuration.

In another example embodiment encompassed by the invention, a fire suppression sprinkler comprises a body surrounding a bore. The bore defines a flow axis arranged coaxially with the bore. In an example, first and second frame arms are mounted on opposite sides of the body and extend therefrom in a direction along the flow axis. The frame arms define a plane. A nose is mounted on the ends of the frame arms. The nose is positioned coaxially with the flow axis. A deflector plate is mounted on the nose and is oriented transversely to the flow axis. The deflector plate has a periphery surrounding a center located on the flow axis. In an example embodiment the deflector plate comprises a plurality of slots of a first configuration extending from the periphery radially toward the center and terminating at a first distance from the center. At least two of the slots of the first configuration are disposed in the plane in this example. At least four slots of a second configuration extend from the periphery radially toward the center and terminate at a second distance from the center. The slots of the second configuration are located about the periphery such that one of the slots of the second configuration is positioned adjacent to each side of each of the slots of the first configuration which are disposed in the plane. A plurality of slots of a third configuration extend from the periphery radially toward the center and terminating at a third distance from the center. The second distance is less than any of the first or third distances in this example.

In an example embodiment the nose has a maximum radius measured from the flow axis. The first, second, and third distances are greater than the maximum radius in an example. By way of example the bore defines a k factor of K=<NUM>/s/(kPa)<NUM>/<NUM> (k=<NUM> gpm/(psi)<NUM>/<NUM>) or greater and the fire suppression sprinkler is adapted to be installed in a pendent orientation.

In an example embodiment the slots of the second configuration have a club shape comprising a handle extending from the periphery and a club head terminating at a distance from the center. A width of the club head proximate to the handle is less than a width of the club head proximate to the center in an example. In another example a widest width of the club head is wider than a widest width of the handle. In a further example the club head has a curved tip at the distance from the center. In an example embodiment the club head is asymmetric with respect to a line extending radially from the center. The club head is defined by a first edge oriented at a first angle with respect to the line, and a second edge, opposite to the first edge. The second edge is oriented at a second angle with respect to the line. The second angle is different from the first angle. In another example each of the slots of the second configuration are symmetric with respect to a line extending radially from the center. By way of example the slots of the second configuration have a keyhole shape comprising a waist extending from the periphery and a key head terminating at a distance from the center. In an example embodiment, a widest width of the key head is wider than a widest width of the waist. Further by way of example, a width of the key head proximate to the waist is equal to a width of the key head proximate to the center. In an example embodiment the key head has a curved tip at the distance from the center. Further by way of example, the key head is symmetric with respect to a line extending radially from the center.

In an example embodiment the slots of the first configuration have an arrowhead shape comprising a shaft extending from the periphery and an arrowhead terminating at a first distance from the center. The arrowhead is asymmetric with respect to a line extending radially from the center. By way of example, the arrowhead is defined by a first edge oriented at a first angle with respect to the line, and a second edge, opposite to the first edge. The second edge is oriented at a second angle with respect to the line. The second angle is different from the first angle. By way of example, a widest width of the arrowhead is wider than a widest width of the shaft. In a further example, a width of the arrowhead proximate to the shaft is greater than a width of the arrowhead proximate to the center. Also by way of example, the arrowhead has a curved tip at the distance from the center. In an example embodiment, the shaft has a width at the periphery which is greater than a width of the shaft proximate to the arrowhead. By way of example, the shaft is defined by first and second oppositely disposed edges. Each edge is angularly oriented with respect to a line extending radially from the center such that the shaft has a width at the periphery which is greater than a width of the shaft proximate to the arrowhead.

In an example embodiment the deflector plate further comprises a plurality of slots of a fourth configuration. Additionally by way of example, the deflector plate further comprises a plurality of slots of a fifth configuration.

The invention encompasses an early suppression fast response fire suppression sprinkler. In an example embodiment the sprinkler comprises a body adapted for use in a pendent orientation. The body surrounds a bore. The bore defines a flow axis arranged coaxially with the bore. The bore defines a k factor of k=<NUM>/s/ (kPa)<NUM>/<NUM> (k=<NUM> gpm/(psi)<NUM>/<NUM>) or greater. First and second frame arms are mounted on opposite sides of the body and extend therefrom in a direction along the flow axis. The frame arms define a plane. A plug is removably mounted on the body between the frame arms and overlies the bore. A nose is mounted on ends of the frame arms at a distance from the plug less than <NUM> (<NUM> inches). The nose is positioned coaxially with the flow axis. A deflector plate is mounted on the nose and oriented transversely to the flow axis. The deflector plate has a periphery surrounding a center located on the flow axis. In an example embodiment the deflector plate comprises a plurality of first slots extending from the periphery radially toward the center and terminating at a first distance from the flow axis. At least two of the first slots are disposed in the plane. A plurality of second slots extend from the periphery radially toward the center and terminate at a second distance from the flow axis. The second slots are located about the periphery such that one of the second slots is positioned adjacent to each side of each of the first slots which are disposed in the plane. The second distance is less than the first distance in an example embodiment. In an example embodiment the nose has a maximum radius measured from the flow axis. The first and second distances are greater than the maximum radius by way of example.

In another example embodiment, a fire suppression sprinkler comprises a body surrounding a bore. The bore defines a flow axis arranged coaxially with the bore. First and second frame arms are mounted on opposite sides of the body and extend therefrom in a direction along the flow axis. A nose mounted on ends of the frame arms. The nose is positioned coaxially with the flow axis. A deflector plate is mounted on the nose and is oriented transversely to the flow axis. The deflector plate has a periphery surrounding a center located on the flow axis and comprises a first slot extending from the periphery radially toward the center. The first slot has an arrow shape comprising a first shaft extending from the periphery and a first arrowhead terminating at a first distance from the center. The first slot is aligned with the first arm. A widest width of the first slot is equal to or greater than a thickness of the first arm in an example.

In an example embodiment the shaft is defined by first and second oppositely disposed edges. Each edge is angularly oriented with respect to a first line extending radially from the center such that the first shaft has a width at the periphery which is greater than a width of the first shaft proximate to the first arrowhead. Further by way of example, a widest width of the first arrowhead is wider than a widest width of the first shaft. In another example, a width of the first arrowhead proximate to the first shaft is greater than a width of the first arrowhead proximate to the center. Also by way of example, the first arrowhead has a curved tip at the first distance from the center. In an example the first slot is symmetric about a first line extending radially from the center.

Further by way of example, a second slot extends from the periphery radially toward the center. The second slot has a club shape comprising a handle extending from the periphery and a club head terminating at a second distance from the center. A width of the club head proximate to the handle is less than a width of the club head proximate to the center in an example. In an example embodiment a widest width of the club head is wider than a widest width of the handle. In a further example the club head has a curved tip at the second distance from the center. In another example the club head is asymmetric with respect to a second line extending radially from the center. In an example embodiment the club head is defined by a first edge oriented at a first angle with respect to the second line, and a second edge, opposite to the first edge. The second edge is oriented at a second angle with respect to the second line. The second angle is different from the first angle in an example embodiment.

An example embodiment further comprises a third slot extending from the periphery radially toward the center. The third slot has a second arrow shape comprising a second shaft extending from the periphery and a second arrowhead terminating at a third distance from the center. The third arrowhead is asymmetric with respect to a third line extending radially from the center in an example embodiment.

Further by way of example, the second arrowhead is defined by a first edge oriented at a first angle with respect to the third line, and a second edge, opposite to the first edge. The second edge is oriented at a second angle with respect to the third line. The second angle is different from the first angle in an example embodiment. By way of example, a widest width of the second arrowhead is wider than a widest width of the second shaft. In another example, a width of the second arrowhead proximate to the second shaft is greater than a width of the second arrowhead proximate to the center. Further by way of example, the second arrowhead has a curved tip at the third distance from the center. In an example embodiment the second shaft has a width at the periphery which is greater than a width of the second shaft proximate to the second arrowhead. By way of example, the second shaft is defined by first and second oppositely disposed edges. Each edge is angularly oriented with respect to the third line such that the second shaft has a width at the periphery which is greater than a width of the second shaft proximate to the second arrowhead. An example embodiment comprises a fourth slot extending from the periphery radially toward the center. The fourth slot has a keyhole shape comprising a waist extending from the periphery and a key head terminating at a fourth distance from the center. In an example a widest width of the key head is wider than a widest width of the waist. In a further example, a width of the key head proximate to the waist is equal to a width of the key head proximate to the center. Further by way of example, the key head has a curved tip at the fourth distance from the center. In an example embodiment the key head is symmetric with respect to a fourth line extending radially from the center.

An example embodiment further comprises a fifth slot extending from the periphery radially toward the center. The fifth slot has a third arrow shape comprising a third shaft extending from the periphery and a third arrowhead terminating at a fifth distance from the center. The third shaft is defined by third and fourth oppositely disposed edges. Each of the third and fourth edges is angularly oriented with respect to a fifth line extending radially from the center such that the third shaft has a width at the periphery which is greater than a width of the third shaft proximate to the arrowhead. In an example embodiment the third shaft has a width at the periphery wider than a width of the first shaft at the periphery. Further by way of example a widest width of the third arrowhead is wider than a widest width of the third shaft. In another example a width of the third arrowhead proximate to the third shaft is greater than a width of the third arrowhead proximate to the center. In another example the third arrowhead has a curved tip at the fifth distance from the center. In an example embodiment the third arrowhead is symmetric with respect to a fifth line extending radially from the center.

The invention further encompasses a fire suppression sprinkler comprising a body surrounding a bore. The bore defines a flow axis arranged coaxially with the bore. First and second frame arms are mounted on opposite sides of the body and extend therefrom in a direction along the flow axis. A nose is mounted on ends of the frame arms. The nose is positioned coaxially with the flow axis. A deflector plate is mounted on the nose and is oriented transversely to the flow axis. The deflector plate has a periphery surrounding a center located on the flow axis and comprises a first slot extending from the periphery radially toward the center. The first slot has an arrow shape comprising a first shaft extending from the periphery and a first arrowhead terminating at a first distance from the center. The first shaft is defined by first and second oppositely disposed edges. Each of the first and second edges is angularly oriented with respect to a first line extending radially from the center such that the first shaft has a width at the periphery which is greater than a width of the first shaft proximate to the first arrowhead. A second slot extends from the periphery radially toward the center. The second slot has an arrow shape comprising a second shaft extending from the periphery and a second arrowhead terminating at a second distance from the center. The second shaft is defined by first and second oppositely disposed edges. Each edge defines the second shaft as angularly oriented with respect to a second line extending radially from the center such that the second shaft has a width at the periphery which is greater than a width of the second shaft proximate to the second arrowhead. The second line is oriented at an angle with respect to the first line. A third slot extends from the periphery radially toward the center. The third slot has a club shape comprising a handle extending from the periphery and a club head terminating at a third distance from the center. In an example a width of the club head proximate to the handle is less than a width of the club head proximate to the center. The third slot is positioned between the first and second slots. A fourth slot extends from the periphery radially toward the center. The fourth slot has an arrow shape comprising a third shaft extending from the periphery and a third arrowhead terminating at a fourth distance from the center. The fourth slot is positioned between the second and third slots. A fifth slot extends from the periphery radially toward the center. The fifth slot has a keyhole shape comprising a waist extending from the periphery and a key head terminating at a fifth distance from the center. The fifth slot is positioned between the second and fourth slots.

In an example embodiment the third slot has the greatest area of any of the first, second, fourth and fifth slots. Further by way of example, the angle between the first and second lines is <NUM>°. In another example, the width of the second shaft at the periphery is greater than the width of the first shaft at the periphery. In an example the third distance is less than the first, second, fourth and fifth distances. Further by way of example the fifth distance is less than the first, second and fourth distances. In another example the first, second and fourth distances are equal to one another.

By way of example the club head is asymmetric with respect to a third line extending radially from the center. In another example the third arrowhead is asymmetric with respect to a fourth line extending radially from the center. An example further comprises a pair of the first slots positioned in the plate <NUM>° from one another. Another example further comprises two of the second slots positioned in the plate respectively at <NUM>° and <NUM>° from one of the first slots. An example, further comprises four of the third slots positioned in the plate respectively at <NUM>°, <NUM>°, <NUM>° and <NUM>° from the one of the first slots. An example embodiment, further comprises four of the fourth slots positioned in the plate respectively at <NUM>°, <NUM>°, <NUM>° and <NUM>° from the one of the first slots. Another example embodiment comprises four of the fifth slots positioned in the plate respectively at <NUM>°, <NUM>°, <NUM>° and <NUM>° from the one of the first slots.

<FIG> and <FIG> show an example fire suppression sprinkler <NUM> according to the invention. Sprinkler <NUM> may be, for example, an early suppression fast response (ESFR) sprinkler having a "k factor" from about <NUM> to about <NUM>, and specifically <NUM>/s/(kPa)<NUM>/<NUM> (about <NUM> to about <NUM>, and specifically <NUM> gpm/(psi)<NUM>/<NUM>).

As shown in <FIG>, sprinkler <NUM> comprises a body <NUM> which surrounds a bore <NUM>. Bore <NUM> defines a flow axis <NUM> arranged coaxially with the bore. Body <NUM> has a nipple <NUM> for connection of the sprinkler <NUM> to a piping network of a fire suppression system (not shown) and a plurality of flat surfaces <NUM> (see <FIG>) which receive a wrench for applying torque to the sprinkler during installation. Nipple <NUM> may be threaded as shown in <FIG> and <FIG>, or, as shown in <FIG>, nipple <NUM> may have a groove <NUM> to enable the use of a mechanical coupling to connect the sprinkler to the piping network of a fire suppression system. First and second frame arms <NUM> and <NUM> extend from opposite sides of body <NUM> parallel to flow axis <NUM> and support a nose <NUM> mounted on the ends of the arms. Arms <NUM> and <NUM> extend along flow axis <NUM> by a length <NUM> as measured from the end of the bore <NUM> to the base of the nose <NUM> (see <FIG>). Nose <NUM> is positioned coaxially with the flow axis <NUM> and supports a heat sensitive trigger <NUM>. Nose <NUM> in this example is conical and has a maximum radius <NUM> (measured from flow axis <NUM>) which transitions into a flow conditioning portion <NUM>. Flow conditioning portion <NUM> is advantageously cylindrical, and extends beyond the ends of arms <NUM> and <NUM> a length <NUM> (see <FIG>), thereby permitting a deflector to be mounted on nose <NUM> in spaced relation to the ends of arms <NUM> and <NUM>.

In this example the heat sensitive trigger <NUM> comprises a frangible glass bulb <NUM> containing a heat sensitive liquid <NUM>. Bulb <NUM> extends between nose <NUM> and a sealing member <NUM>, in this example a plug <NUM> which overlies and seals the bore <NUM> through engagement with body <NUM>. As shown in <FIG>, nose <NUM> also comprises a set screw <NUM>, threaded within a bore <NUM> in nose <NUM> aligned with the bulb <NUM>. The set screw <NUM> permits assembly of the bulb <NUM> into the sprinkler <NUM> and adjustment of the compression force on the bulb. Bulb <NUM> supports the plug <NUM> to maintain the sprinkler <NUM> in its closed configuration (shown). Bulb <NUM> breaks when the ambient temperature reaches a predetermined value, for example, indicative of a fire. In various embodiments, such predetermined temperature values may be approximately <NUM> (<NUM>°F) or <NUM> (<NUM>°F). When the bulb <NUM> breaks it no longer supports plug <NUM> which is then released from engagement with the body <NUM> to open sprinkler <NUM> and allow water or other fire suppressing fluid to be discharged. Other heat sensitive triggers are also feasible, such as those having components held together by a solder which melts at a predetermined temperature to allow the sprinkler to open.

A deflector <NUM> is mounted on the nose <NUM>. As shown in <FIG> and <FIG>, the example deflector <NUM> comprises plate <NUM>, advantageously circular and in a plane oriented transversely to the flow axis <NUM>. Plate <NUM> has a periphery <NUM> surrounding a center <NUM>, the center being coincident with the flow axis <NUM>. Plate <NUM> has a thickness <NUM> (see <FIG>). The deflector <NUM> is positioned in spaced relation to the ends of arms <NUM> and <NUM> at the distance <NUM>. In an example embodiment, the distance <NUM> is greater than twice the thickness <NUM> of plate <NUM>. In another example embodiment, the distance <NUM> is approximately three times the thickness <NUM> of the plate <NUM>.

As shown in <FIG> and <FIG>, plate <NUM> defines a plurality of slots <NUM>. Slots <NUM> are designed in conjunction with nose <NUM>, arms <NUM> and <NUM> (including the length <NUM>), flow conditioning region <NUM> (including length <NUM>), and bore <NUM> to meet standards governing discharge rate, coverage area size and shape, and other performance standards in order to permit installation under NFPA <NUM>, including passage of the testing set forth in standards promulgated by FM Global and UL, such standards including UL <NUM> and FM <NUM>.

The example sprinkler <NUM> is further designed to achieve higher performance, including enabling the higher density storage of commodities by being qualified under UL <NUM> (and permitted under NFPA <NUM>) to be installed in specific applications where the ceiling height is a maximum of <NUM> meters (<NUM> feet), the commodity height is a maximum of <NUM> meters (<NUM> feet) and where the aisle spacing is a minimum of <NUM> meters (<NUM> feet).

To this end, slots <NUM> comprise slots of five configurations, slots <NUM>, slots <NUM>, slots <NUM>, slots <NUM>, and slots <NUM>, respectively, all of which extend radially from the periphery <NUM> of the plate <NUM> toward the plate center <NUM>, each slot extending along a respective line <NUM>, <NUM>, <NUM>, <NUM> and <NUM> which extend radially from the plate center <NUM>.

As is apparent from <FIG>, slots <NUM> are aligned with the first and second arms <NUM> and <NUM> which are disposed in a plane <NUM>. As shown in <FIG> and <FIG>, slots <NUM> extend from the periphery <NUM> of the plate <NUM> and terminate at points 64a which lie at a distance <NUM> from the plate center <NUM>. Slots <NUM> are of generally arrow shape, arrow shape meaning that slots <NUM> have a shaft 64b extending from the periphery <NUM> and an arrowhead 64c terminating in a curved tip 64d at point 64a. Slots <NUM> in this example are symmetric about line <NUM> and the arrowhead 64c has a width 64e proximate to the shaft 64b which is greater than its width 64f proximate the plate center <NUM>. As shown in <FIG>, width 64e may be advantageously equal to or greater than the thicknesses 24a and 26a of the arms <NUM> and <NUM> respectively. With reference again to <FIG> and <FIG>, width 64e, the widest width of the arrowhead 64c is also wider than the widest width of the shaft 64b in this example.

Advantageously, the shaft 64b is defined by first and second oppositely disposed edges <NUM> and <NUM> which are angularly oriented with respect to line <NUM> such that shaft 64b has a width 64i at the plate periphery <NUM> which is greater that a width 64j of the shaft 64b proximate to the arrowhead 64c.

As shown in <FIG>, <FIG> and <FIG>, slots <NUM> are adjacent each side of the two slots <NUM>, and extend from the periphery <NUM> of plate <NUM> to terminate at points 66a which lie at a distance <NUM> from the plate center <NUM>. Slots <NUM> are generally club shaped, club shape meaning that slots <NUM> comprise a handle 66b extending from the periphery <NUM> and a club head 66c terminating at point 66a. The width 66d of the club head 66c proximate to handle 66b is less than the width 66e of the club head proximate to the plate center <NUM>. Club head 66c terminates at point 66a in a curved tip 66f. The widest width 66e of the club head is wider than the widest width <NUM> of the handle 66b.

As shown in <FIG>, slots <NUM> are preferably asymmetric about lines <NUM>. Club head 66c is defined by a first edge <NUM> oriented at a first angle 66i with respect to line <NUM>, and a second edge 66j oriented at a second angle <NUM> with respect to line <NUM>. Angle 66i is different from angle <NUM> to produce the asymmetry of slots <NUM>. Slots <NUM> advantageously have the largest surface area of any of slots <NUM>, <NUM>, <NUM> and <NUM>.

As shown in <FIG>, <FIG> and <FIG>, slots <NUM> extend from the periphery <NUM> of the plate <NUM> and terminate at points 68a which lie at a distance <NUM> from the plate center <NUM>. Slots <NUM> are of generally arrow shape, arrow shape meaning that slots <NUM> have a shaft 68b extending from the periphery <NUM> and an arrowhead 68c terminating in a curved tip 68d at point 68a. The arrowhead 68c has a width 68e proximate to the shaft 68b which is greater than its width 68f proximate the plate center <NUM>. Width 68e, the widest width of the arrowhead 68c is also wider than the widest width of the shaft 68b in this example.

Advantageously, the shaft 68b is defined by first and second oppositely disposed edges <NUM> and <NUM> which are angularly oriented with respect to line <NUM> such that shaft 68b has a width 68i at the plate periphery <NUM> which is greater that a width 68j of the shaft 68b proximate to the arrowhead 68c.

As shown in 4B, slots <NUM> in this example are asymmetric about line <NUM>. Arrowhead 68c is defined by a first edge <NUM> oriented at a first angle <NUM> with respect to line <NUM>, and a second edge 68n oriented at a second angle 68p with respect to line <NUM>. Angle <NUM> is different from angle 68p to produce the asymmetry of slots <NUM>.

As shown in <FIG>, <FIG> and <FIG>, slots <NUM> lie between slots <NUM> and <NUM> and extend along line <NUM> from the plate periphery <NUM> to terminate at a point 70a at a distance <NUM> from the plate center <NUM>. Slots <NUM> are generally elongate keyhole shaped, elongate keyhole shaped meaning that slots <NUM> comprise a waist 70b extending from periphery <NUM> and a key head 70c terminating at point 70a in a curved tip 70d. Slots <NUM> are symmetric about lines <NUM> in this example. The width 70e of the key head 70c proximate the waist 70b is equal to the width 70f of the key head proximate the plate center <NUM>. The widest width 70e or 70f is wider than the widest width <NUM> of the waist 70b.

<FIG> shows another example that is not according to the present invention, wherein slots <NUM>, having the keyhole shape, are positioned adjacent each side of the two slots <NUM>, and extend from the periphery <NUM> of plate <NUM>, effectively replacing slots <NUM>.

As shown in <FIG>, <FIG> and <FIG>, slots <NUM> extend from the periphery <NUM> of the plate <NUM> and terminate at points 72a which lie at a distance <NUM> from the plate center <NUM>. Slots <NUM> are of generally arrow shape, arrow shape meaning that slots <NUM> have a shaft 72b extending from the periphery <NUM> and an arrowhead 72c terminating in a curved tip 72d at point 72a. Slots <NUM> in this example are symmetric about lines <NUM> and the arrowhead 72c has a width 72e proximate to the shaft 72b which is greater than its width 72f proximate the plate center <NUM>. Width 72e, the widest width of the arrowhead 72c is also wider than the widest width of the shaft 72b in this example.

Advantageously, the shaft 72b is defined by first and second oppositely disposed edges <NUM> and <NUM> which are angularly oriented with respect to line <NUM> such that shaft 72b has a width 72i at the plate periphery <NUM> which is greater that a width 72j of the shaft 72b proximate to the arrowhead 72c. It is also advantageous when width 72i is greater than the width 64i of the shaft 64b at the periphery. It is also advantageous for line <NUM> to be oriented at <NUM>° to line <NUM>, resulting in slot <NUM> being oriented at <NUM>° to slot <NUM>. Additionally, with respect to the distances <NUM>, <NUM>, <NUM>, <NUM> and <NUM>, it is advantageous if distance <NUM> is less than distances <NUM>, <NUM>, <NUM> and <NUM>. It is further advantageous if the distance <NUM> is less than distances <NUM>, <NUM> and <NUM>. Moreover, it is advantageous if distances <NUM>, <NUM> and <NUM> are equal to one another.

The example arrangement of the slots <NUM> shown in <FIG> is expected to be advantageous. In this arrangement there are five different types of slots <NUM>. Slots <NUM> may be regarded as a pair of first slots (first configuration) positioned in plate <NUM> at <NUM>° from one another. Slots <NUM> may be considered a pair of second slots (fifth configuration) positioned in plate <NUM> at <NUM>° and <NUM>° from either one of the first slots <NUM>. Slots <NUM> may be considered as third slots (second configuration). In the example arrangement, there are four of the second configuration slots <NUM> positioned in plate <NUM> at <NUM>°, <NUM>°, <NUM>°and <NUM>° from one of the first slots <NUM>. Slots <NUM> may be considered to be fourth slots (third configuration). In the example arrangement there are four third configuration slots positioned in plate <NUM> respectively at <NUM>°, <NUM>°, <NUM>° and <NUM>° from one of the first slots <NUM>. Slots <NUM> may be considered to be fifth slots (fourth configuration type). In the example arrangement there are four fourth configuration slots positioned in plate <NUM> respectively at <NUM>°, <NUM>°, <NUM>° and <NUM>° from one of the first slots <NUM>. It is understood that the angular separation of the slots are exemplary nominal angles subject to manufacturing tolerances and thus may vary from those as specified herein.

The arrangement of slots <NUM> as shown in <FIG> may also be characterized based upon the distance at which the slots terminate from the flow axis <NUM>. In the example embodiment shown, a plurality of first slots, including, for example, slots <NUM>, <NUM> and <NUM>, and a plurality of second slots, including, for example, slots <NUM> and <NUM>, extend radially from the periphery <NUM> toward the flow axis <NUM>. In particular, two of the first slots <NUM> are disposed in the plane <NUM> (aligned with the arms <NUM> and <NUM>) and one of the second slots <NUM> are positioned adjacent to each side of each of the first slots <NUM> which are disposed in plane <NUM>. With reference to <FIG>, it is thought advantageous for the termination distance <NUM> of second slots <NUM> from the flow axis <NUM> be less than the termination distance <NUM> from the flow axis of the first slots <NUM>. Further advantage is believed possible if the termination distances <NUM> and <NUM> from the flow axis <NUM> are greater than the maximum radius <NUM> (see <FIG>) of the nose <NUM>. For a pendent ESFR sprinkler <NUM> (see <FIG> and <FIG>) with the arrangement of first and second slots described above, it is desirable that the nose <NUM> be mounted on ends of the frame arms <NUM> and <NUM> at a distance <NUM> of less than <NUM> (<NUM> inches) from the plug <NUM> as shown in <FIG>. As shown in <FIG>, pendent sprinklers are mounted in a pipeline <NUM> with the flow axis <NUM> oriented vertically so that the discharge of fire suppressing fluid is in a downward direction.

The arrangement of slots <NUM>, meaning their angular separation, shape, sizing as well as their orientation and spacing with respect to arms <NUM> and <NUM> according to the invention is believed to promote improved performance of fire sprinklers, especially of ESFR sprinklers, by advantageously compensating for the effect known as frame shadowing, whereby arms <NUM> and <NUM> represent a discontinuity in the flow of fluid exiting bore <NUM> to impinge upon deflector <NUM>. In particular, it is believed that the location of slots with the largest surface area or which extend the deepest toward the axis <NUM> (such as slots <NUM>) adjacent to the slots located above the frame arms (such as slots <NUM>) helps to compensate for frame shadowing. It is further believed that the location of symmetric slots remote from the location of the frame arms (such as slots <NUM> and <NUM>) where the effect of frame shadowing is at a minimum promotes uniform distribution of fluid where the flow is at its most uniform due to the limited effects of frame shadowing. This arrangement may also be viewed as one where any of slot length, area, and asymmetry is generally reduced from a localized maximum above or adjacent to the frame arms to a localized minimum equidistant from the frame arms, and that such reduction takes place independently on the first and second slots having different termination distances from the flow axis. The advantageous arrangements of the invention, which offer improved compensation for the effects of frame shadowing, result in a more uniform distribution of water discharged from sprinkler <NUM> is promoted that is believed to result in improved performance.

Claim 1:
A fire suppression sprinkler (<NUM>), said sprinkler (<NUM>) comprising:
a body (<NUM>) surrounding a bore (<NUM>), said bore (<NUM>) defining a flow axis (<NUM>) arranged coaxially with said bore (<NUM>);
first and second frame arms (<NUM>, <NUM>) mounted on opposite sides of said body (<NUM>) and extending therefrom in a direction along said flow axis (<NUM>), said frame arms (<NUM>, <NUM>) defining a plane;
a nose (<NUM>) mounted on the ends of said frame arms (<NUM>, <NUM>), said nose (<NUM>) being positioned coaxially with said flow axis (<NUM>);
a deflector plate (<NUM>) mounted on said nose (<NUM>) and oriented transversely to said flow axis (<NUM>), said deflector plate (<NUM>) having a periphery (<NUM>) surrounding a center (<NUM>) located on said flow axis (<NUM>), said deflector plate (<NUM>) comprising:
a plurality of slots (<NUM>) of a first configuration extending from said periphery (<NUM>) radially toward said center (<NUM>), at least two of said slots (<NUM>) of said first configuration being disposed in said plane, wherein said slots (<NUM>) of said first configuration have an arrowhead shape comprising a shaft (64b) extending from said periphery (<NUM>) and an arrowhead (64c) terminating at a first distance from said center (<NUM>), wherein said arrowhead (64c) is asymmetric with respect to a line (<NUM>) extending radially from said center (<NUM>);
at least four slots (<NUM>) of a second configuration extending from said periphery (<NUM>) radially toward said center (<NUM>) and being located about said periphery (<NUM>) such that one of said slots (<NUM>) of said second configuration is positioned adjacent to each side of each of said slots (<NUM>) of said first configuration which are disposed in said plane;
a plurality of slots (<NUM>) of a third configuration extending from said periphery radially toward said center (<NUM>); wherein
said slots (<NUM>) of said second configuration have a greater area than said slots (<NUM>) of said first configuration,
characterised in that said slots (<NUM>) of said second configuration have a club shape comprising a handle (66b) extending from said periphery (<NUM>) and a club head (66c) terminating at a distance from said center (<NUM>), wherein a width (66d) of said club head (66c) proximate to said handle (66b) is less than a width (66e) of said club head (66c) proximate to said center (<NUM>).