Sprinkler head with heat sensitive cover release and valve release mechanism

A sprinkler head with a valve automatically detachable when the temperature is raised to such extent that there is a danger of the outbreak of a fire in a room. The sprinkler head has a water discharge valve seat in the lower center of a discoidal body, a plurality of supporting legs being formed on the outside of the valve seat. A valve in contact with the valve seat is supported by a heat sensitive sustaining unit having a plurality of levers, a fusible retainer disposed on said supporting legs holding the valve and the cover. A deflector made of a thin material having a multiplicity of sprinkling outlets is mounted on the lower part of the body. There is a cover on the outer side of the deflector which is released by the heat sensitive unit.

BACKGROUND OF THE INVENTION 
The invention relates to a sprinkler head, and particularly to sprinkling 
outlets of a sprinkler head having a construction in which a deflector 
made of a thin material is secured to the lower part of a discoidal body 
and a cover for shielding the deflector. 
BRIEF DESCRIPTION OF THE PRIOR ART 
In the conventional sprinkler head, two methods were adopted to disperse 
the jet water while retaining the pressure inside the deflector: one was 
to disperse the water by rotation, while the other was to provide a 
multiplicity of slit-like elongated holes or variform small holes in the 
direction of the dispersion of water. These method had a disadvantage in 
that not only the construction was complicated but also the holes were not 
free from the danger of being clogged by foreign matters in the piping. 
These methods had a further disadvantage in that dust infiltrating from 
outside into the deflector through its sprinkling outlets caused a failure 
in operation in time of emergency when the sprinkler head was installed in 
a dusty place. 
OBJECTS OF THE INVENTION 
An object of the invention is to provide a cover to shield the sprinkling 
outlets and the deflector of the sprinkler head in order to obviate the 
above-mentioned difficulties. 
Further objects, construction and features of the sprinkler head according 
to the invention will become apparent from the description taken in 
reference to the accompanying drawings.

DETAILED DESCRIPTION 
Referring to FIGS. 1 and 4 showing the first embodiment of the invention, 
the numeral 1 designates a discoidal body formed by casting or the like, a 
threaded tube 2 for connecting a water pipe thereto being provided in the 
upper center of the body 1, a water discharge valve seat 3 being formed in 
the lower center thereof, a supporting leg 4 being integrally formed on 
each side of the valve seat 3, a downward edge 5 being formed on the outer 
periphery of the body 1. 
The numeral 6 designates a valve with a packing of sheet copper or the like 
superposed thereon, a valve spindle 7 being erected in the lower center 
thereof, the upper end of a guide sleeve 8 being fitted onto the valve 
spindle 7, a spring-guide 11 with a seat plate 12 superposed thereon being 
loosely fitted through its central hole onto the sleeve 11 so as to be 
supported by a flange 9 at its upper end. Guide pieces 13 downwardly 
provided on the outer periphery of the seat plate are fitted between 
projections 14 on the outer periphery of the guide 11. 
An upper ring 15 is externally fitted onto the sleeve 8 so that its upper 
part is received by a shoulder of said sleeve 8, an annular fusible member 
18 being fitted below the lower part of the upper ring 15, a lower ring 16 
being fitted in such manner that the fusible member 18 is interposed 
between the upper and lower rings 15, 16. 
The numeral 19 designates an annular balancer fitted onto a small diameter 
portion of the lower part of the lower ring 16, a heat collector 21 being 
secured further therebelow, a supporter at each side of the balancer 19 
being engaged with an engageing hole at the lower end of each of a pair of 
levers 22. The top of an angle 23 on the outside of the upper end of each 
lever 22 is brought into contact with the lower part of the outer 
periphery of the guide 11 while the lower part of the outer end of the 
angle 23 is engaged with a receiver 24 on the inside of the lower end of 
each supporting leg 4. 
The numeral 27 designates a pressure screw screwed into female threads 
inside the sleeve 8, a ball 28 being interposed between the upper end of 
the pressure screw 27 and the lower end of the valve spindle 7. 
The numeral 29 designates a deflector made by press-molding a thin metal 
sheet or the like. The deflector 29 has a tapering shape, the upward edge 
17 of its outer periphery being fitted inside the downward edge 5 of the 
body 1 and secured thereto by means of caulking or by the use of an 
adhesive. In the center of the deflector 29 is formed an opening 30 
permitting the heat collector 21, the lower ring 16, levers 22, etc. to 
project therethrough. When the opening 30 is formed, an elongated piece is 
left at two points of the peripheral edge of said opening 30, said 
elongated pieces being erected upright on the peripheral edge so as to 
serve as guide shafts 20. The guide shafts 20 are provided most adjacent 
the outer periphery of the valve 6, while the inner sides of the 
supporting legs 4 are adapted to have vertical faces adjacent the outer 
periphery of the valve 6 so as to serve as guide faces 10. 
Furthermore, the deflector 29 is provided with a plurality of substantially 
triangular sprinkling outlets 31, an elongated triangular projection 32 
being erected inside the deflector 29 so as to stand upright from the 
middle of a side corresponding to the base of each sprinkling outlet 31 
adjacent the center of the deflector 29 thereby enabling the water to be 
dispersed. 
A second embodiment shown in FIG. 2 has some parts in common with the first 
embodiment. Therefore, description will be given hereunder in connection 
with the different parts only. 
In the second embodiment are used a pair of levers 35 each having an 
outward upper element 33 and lower element 34, the top of an angle 36 at 
the outer end of the upper element 33 being brought into contact with the 
lower part of the guide 11, while the lower part of said angle 36 is 
engaged with a receiver 24, respectively. Indentation formed on the 
underside of the lower element 34 are engaged with the corresponding 
indentation formed on an annular coupler 37, a core ring 40 being 
superposed on both lower elements 34, a skid-proof key 38 being interposed 
between the coupler 37 and each lower element, a fusible member being 
applied between the lower element 34, the coupler 37 and the core ring 40 
for integral adhesion thereof. The lower elements 34 and the coupler 37 
project downwardly through and beyond the opening 30 of the deflector 29. 
In the center of the coupler 37 is provided an insertion hole 39 for a 
wrench for revolving the pressure screw 27. 
The sprinkler head according to the invention has a construction as 
described hereinbefore. In the state as shown in FIGS. 1 and 2, the water 
pressure applied to the valve 6 through the threaded tube 2 is sustained 
by a heat sensitive sustaining unit comprising the guide 11, the levers 22 
or 35 and the like. If the fusible member is melted due to, for example, 
the outbreak of a fire, said heat sensitive sustaining unit disintegrates 
and falls, the released valve 6 lowering until it is horizontally 
supported by the receivers 24 of the supporting lets as shown in FIG. 3. 
Thus, the water discharged from within the valve seat 3 is dispersed in 
collision with the valve 6, the water being further dispersed by the 
projections 32 erected adjacent the inner sides of the sprinkling outlets 
31 respectively until it is sprinkled through the sprinkling outlets 31. 
The first and second embodiments perform the operation as described 
hereinbefore. The sprinkler head is adapted to disperse and sprinkle water 
while retaining pressure inside the deflector which is made of thin 
material and mounted on a discoidal body. It is particularly to be noted 
that a projection 32 is erected adjacent the inner side of each sprinkling 
outlet 31 provided in multiplicity on the deflector 29, that is, in the 
middle of the side corresponding to the base of each triangular sprinkling 
outlet 31, whereby the water dispersed in collision with the valve 6 is 
further dispersed in collision with the projections 32 until it is 
sprinkled through the sprinkling outlets 31. Thus the water is sprinkled 
uniformly all over a wide range without deflection. 
A third and fourth embodiments as shown in FIGS. 5 and 6 will be described 
in detail hereinunder. Since they are same as the first and second 
embodiments except the cover, the description will be limited to the 
different parts. 
The numeral 41 designates a cover made by press-molding a thin metal sheet 
or the like. The cover 41 has a tapering shape so as to fit the outside of 
the deflector 29. It has an opening 42 in the center thereof, the lower 
ends of the guide pieces 13 being fitted into the opening 42, catches 43 
at the lower ends thereof being engaged with the lower part of the 
peripheral edge of the opening 42, the upper end of the cover 41 being 
brought into contact with the lower part of the downward edge 5 of the 
body 1. 
The third and fourth embodiments have the above-described construction. In 
the state as shown in FIGS. 5 and 6, the water pressure applied to the 
valve 6 through the threaded tube 2 is sustained by a heat sensitive 
sustaining unit comprising the guide 11, the levers 22 or 35 and the like. 
If the fusible member is melted due to, for example, the outbreak of a 
fire, the heat sensitive sustaining unit disintegrates and falls, the 
released valve 6 lowering until it is supported horizontally by the 
receivers provided on the supporting legs 4 as shown in FIG. 2. 
When the heat sensitive sustaining unit disintegrates as described 
hereinbefore, the spring-guide 11 supported by the levers 22 or 35 also 
disintegrates, the guide pieces 13 lowering along the openings 30, 42, the 
catches 43 at the lower ends of the guide pieces 13 being disengaged from 
the opening 42 of the cover 41. Thus the cover 41 falls off the surface of 
the deflector 29, the sprinkler head being now in the state in which the 
released valve alone is supported horizontally by the receivers 24 as 
shown in FIG. 2. As a result, the water discharged from within the valve 
seat 3 is dispersed in collision with the valve 6 until it is sprinkled 
through the sprinkling outlets of the deflector 29. 
The third and fourth embodiments perform the above-mentioned operation. 
Since the sprinkler head comprises a discoidal body and a deflector made 
of thin material, it is not only very light in weight but also producible 
with economy. Particularly, the sprinkler head has an advantage in that 
infiltration of dust through the sprinkling outlets is completely excluded 
since they are closed by the cover spread over the deflector. It has a 
further advantage in that there is no danger of the cover being 
inadvertently detached insofar as the sensitive sustaining unit is intact 
since a plurality of outward catches at the lower ends of the downward 
guide pieces provided on the outer periphery of the seat plate of the heat 
sensitive sustaining unit inside the deflector engage with the lower side 
of the peripheral edge of the opening in the center of the cover, while 
sprinkling is performed with reliability since the cover is quickly 
detached when the heat sensitive sustaining unit disintegrates with the 
outbreak of a fire. 
The sprinkler head, a fifth embodiment, shown in FIGS. 9 to 11 and the 
sprinkler head shown in FIGS. 12, 14, 16 and 18 are the same sprinkler 
heads as those publicly known under U.S. Pat. No. 3,525,402 and British 
Pat. No. 1,313,897 respectively which have been obtained by the present 
applicant. The only difference consists in that the sprinkling outlets and 
the deflector are shielded with a cover thereby enabling to preclude dust 
from infiltrating into the deflector through the sprinkling outlets. The 
sprinkler head shown in FIGS. 9 to 11 has outward catches 43 at the lower 
ends of the guide pieces 13, said catches 43 supporting the cover by 
engaging with the underside of the peripheral edge of the opening in the 
center of the cover 41. 
The sprinkler head shown in FIGS. 12 and 13 has a notch 44 provided on each 
downward guide piece 13, on the peripheral edge of the opening 45 of the 
cover 41 being provided a projection 46 engageable with each notch 44, the 
cover being applied to the outside of the deflector by engaging the 
projections 46 with the notches 44. 
In the sprinkler head shown in FIGS. 14 and 15, downward projections 47 are 
provided on the peripheral edge of the opening in the center of the cover 
so as to correspond with the guide pieces 13 of the seat plate, 
respectively, the cover being applied to the outside of the deflector by 
connecting the guide pieces 13 with the downward projections 47 by 
suitable means. 
In the sprinkler head shown in FIGS. 16 and 17, threads 48 are provided in 
the lower part of each downward guide piece 13, a downwardly projecting 
edge 49 being provided on the periphery of the opening 45 of the cover 41, 
threads 50 being provided on said projecting edge 49. The cover is applied 
to the outside of the deflector by screwing its threads 50 into the 
threads 48 of the guide pieces. 
In the sprinkler head shown in FIGS. 18 and 19, a plurality of notches 51 
are provided on the coupler 37, projections 52 corresponding with said 
notches 51 being provided on the peripheral edge of the opening 45 in the 
center of the cover 41, an engaging recess 53 being provided on each 
projection 52 thereby enabling to hold the peripheral edge of the coupler 
37. The cover 41 is applied by first fitting the projections 52 of the 
cover 41 into the notches 51 of the coupler 37, then the cover 41 being 
rotated to some extent so that the peripheral edge of the coupler is 
engaged with the engaging recesses 53 of the projections 52. 
In each of the embodiments described hereinbefore, the sprinkling outlets 
of the deflector are closed by the cover same as in the case of the third 
and fourth embodiments. Therefore, there is no danger of dust infiltrating 
into the deflector through the sprinkling outlets.