JP5178897B2 - Sprinkler head - Google Patents

Description

The present invention relates to a sprinkler head.

In a conventional sprinkler head, a thermal decomposition portion is covered with a cover to improve the aesthetics, and a device that surrounds the thermal decomposition portion with a cover attached to a frame has been proposed (for example, a cover attached to a frame). , See Patent Document 1).
Japanese Patent Application Laid-Open No. 07-231949

A conventional sprinkler head has a structure in which a thermal element is projected from the lowermost end of the head in order to achieve high sensitivity. For this reason, the thermal decomposition mechanism including the thermal element is easily affected by external force, and has a problem that it may be broken or deformed by an external impact to cause malfunction or water leakage.
In order to protect from external force, it is conceivable to move the position of the thermal element from the lowermost end of the head to the upper part. However, if this is done, the heat generated by the hot air current cannot be collected and the heat receiving efficiency is reduced. There was a problem.
The present invention has been made to solve the above-described problems, and an object of the present invention is to obtain a sprinkler head that is hardly affected by external force.
It is another object of the present invention to obtain a sprinkler head that can improve the heat receiving efficiency even when the thermosensitive element is not provided at the lower end of the head.

The present invention is a sprinkler head comprising a head body having a water discharge port, a valve body that closes the water discharge port, and a thermal decomposition mechanism that supports the valve body , wherein the thermal decomposition mechanism includes a thermal element, A sprinkler head comprising a heat sensitive plate integrally fixed below so as to transmit heat to the heat sensitive element, and is located below the heat sensitive element and on the outer periphery thereof, and receives an external force. A guard member is provided, and the heat sensitive plate is provided below the guard member, and the heat sensitive plate has a disk-shaped outer peripheral portion whose outer diameter is less than the outer diameter of the head body, and an inner side of the outer peripheral portion. It is bent so as to have an inclined surface inclined toward the thermal element .

In the present invention, since the guard member that receives the external force is provided below the thermal element provided in the thermal decomposition mechanism and located on the outer periphery thereof, it can be made less susceptible to the influence of the external force. Since the heat sensitive plate is provided below the guard member and the heat sensitive plate is bent so as to have an inclined surface inclined toward the heat sensitive element, the heat sensitive element protected by the guard member protrudes from the lower end of the head. Even if it is not, the heat receiving efficiency can be improved.

It is a longitudinal cross-sectional view which concerns on Embodiment 1 of this invention. It is a longitudinal cross-sectional view of the head main body of FIG. It is a longitudinal cross-sectional view of the frame of FIG. It is a longitudinal cross-sectional view of the valve body of FIG. It is a figure which shows the deflector assembly of FIG. It is a figure which shows the thermal decomposition mechanism of FIG. FIG. 2 shows the heat sensitive plate of FIG. 1, wherein (a) is a plan view and (b) is a cross-sectional view. It is an external view of FIG. It is operation | movement explanatory drawing which concerns on Embodiment 1 of this invention. It is operation | movement explanatory drawing which concerns on Embodiment 1 of this invention. It is operation | movement explanatory drawing which concerns on Embodiment 1 of this invention. It is an external view concerning Embodiment 2 of the present invention. It is an external view concerning Embodiment 3 of the present invention. It is a top view of the heat sensitive board concerning Embodiment 4 of the present invention. It is a longitudinal cross-sectional view which concerns on Embodiment 5 of this invention.

[Embodiment 1]
1 is a longitudinal sectional view according to the first embodiment of the present invention, FIG. 2 is a longitudinal sectional view of the head main body of FIG. 1, FIG. 3 is a longitudinal sectional view of the frame of FIG. FIG. 5 shows the deflector assembly of FIG. 1, FIG. 6 shows the thermal decomposition mechanism of FIG. 1, FIG. 7 shows the thermal plate of FIG. 1, (a) is a plan view, (b) ) Is a sectional view, and FIG. 8 is an external view of FIG.
In the figure, reference numeral 1 denotes a head body having a central portion penetrating therein and having a water discharge port 2 therein. The upper surface of the flange 4 is provided with a screw portion 3 connected to the water supply pipe, and the lower surface of the flange 4 is provided with a cylindrical portion provided with a screw portion 5 into which a frame 10 (also referred to as a frame portion) to be described later is screwed. 6 is projected. The cylindrical portion 6 is formed with a hole 7 in the circumferential direction in which a post 23 described later is loosely fitted. Further, a groove portion 8 is formed on the inner peripheral surface side of the cylindrical portion 6. The groove portion 8 is formed with a tapered surface with which a lock ball 71 described later contacts. The frame 10 only needs to be connected to the head body 1. For example, both may be integrated, and in this case, the frame 10 is a frame portion.

Reference numeral 10 denotes a cylindrical frame coupled to the head main body 1, which is longer than the cylindrical portion 6, and a female screw portion 11 that is screwed into the screw portion 5 of the head main body 1 is provided at the upper portion. At the lower end, a flange-shaped step 12 is formed in an annular shape inside.
A valve body 15 closes the water outlet 2 of the head body 1. The valve body 15 has an outer diameter main body 51 slightly smaller than the inner diameter of the cylindrical portion 6 of the head main body 1, and a head 52 that protrudes from the central upper surface of the main body 51 and is inserted into the water outlet 2 of the head main body 1. In addition, the main body 51 includes a stepped portion 54 that protrudes upward from the outer peripheral portion of the upper surface 53 that is the water outlet side.

  Between the valve body 15 and the water outlet 2, for example, a fluororesin is coated, and a circular disc spring 17 having a substantially C-shaped cross section is interposed. The disc spring 17 is formed in a donut shape, and a connecting hole is provided in the center. The inner diameter of the connection hole is substantially the same as the outer diameter of the head 52 of the valve body 15, and the disc spring 17 is attached to the head 52 of the valve body 15 through the connection hole. The disc spring 17 is in contact with the water discharge port edge 9 on the outer periphery of the lower end of the water discharge port 2. Further, the upper surface of the stepped portion 54 of the valve body 15 is in contact with the water discharge port edge 9 of the head body 1 outside the disc spring 17 so that the disc spring 17 has a predetermined displacement. A gap is formed between 53 and the lower surface of the water discharge port edge 9 of the head body 1. As a result, a predetermined restoring force acting upward is generated on the outer peripheral side of the disc spring 17, the outer peripheral edge of the disc spring 17 is in pressure contact with the water discharge port edge 9, and acts downward on the inner peripheral side. A predetermined restoring force is generated, and the inner peripheral edge of the disc spring 17 is brought into pressure contact with the upper surface 53 of the valve body 15 to keep the water outlet 2 and the valve body 15 watertight. In order to improve the corrosion resistance, a fluororesin coating is applied, but this may be omitted.

  A deflector assembly 20 includes a deflector 21, a support 23, a stopper ring 25, and a valve body 15. The support column 23 is formed with a flange-like locking portion at the upper end and the lower end thereof, and is inserted into the hole 7 of the head body 1. The stopper ring 25 has a through hole in which the support 23 is loosely fitted in the circumferential direction, and its inner diameter is slightly larger than the outer diameter of the main body 51 of the valve body 15, and the outer diameter is larger than the inner diameter of the frame 10. It is small and is sized to be locked to the stepped portion 12 of the frame 10 when the water is lowered during water discharge. The disc-shaped deflector 21 has through holes into which the support columns 23 are fitted in the circumferential direction, and the outer diameter thereof is smaller than the inner diameter of the step portion 12 of the frame 10, and the inner diameter is the main body portion 51 of the valve body 15. The valve body 15 is locked when the water is lowered when the water is discharged.

  Reference numeral 30 denotes a thermal decomposition mechanism that supports the valve body 15 and includes a ball support cylinder 31, a thermal part 40, and a guard member 35. The cylindrical ball support cylinder 31 is slidably disposed in the frame 10 and, for example, six insertion holes 32 of a lock ball 71 described later are formed in the upper side surface thereof. In addition, the inner diameter of the lower part is reduced, and a screw part to which a cylinder 41 described later is screwed is formed on the inner peripheral surface, and a screw part to which a guard member 35 described later is screwed on the lower outer peripheral surface. Is formed. The inner diameter of the insertion hole 32 is formed larger than the outer diameter of the lock ball 71. Further, the upper outer diameter of the ball support cylinder 31 is formed in substantially the same shape as the main body 51 of the valve body 15, and an annular step is formed on the lower surface of the main body 51, so that the valve body is formed above the ball support cylinder 31. 15 is locked.

  The heat sensitive unit 40 includes a cylinder 41, a heat sensitive plate 42, a fusible alloy 62, and a piston 63. The cylinder 41 is formed in a bottomed cylindrical shape, and is screwed into the ball support cylinder 31 by a screw portion provided at the upper part of the outer periphery, and the lower part protrudes from the lower end of the ball support cylinder 31. Further, after inserting a connection hole of the heat sensitive plate 42 on the lower surface, the heat sensitive plate 42 is integrated and fixed by caulking. The fusible alloy 62 serving as the heat sensitive element may not be an alloy, and may be a fusible piece made of resin, for example.

  The fusible alloy 62 is a heat-sensitive element made of, for example, compression solder, and is accommodated under the piston 63 in the cylinder 41 and melted by heat. The fusible alloy 62 protrudes downward from the lower surface of the ball support cylinder 31 and is provided at a position where it can easily hit a hot air stream.

  The piston 63 is formed in a T-shaped cross section and is accommodated in the cylinder 41 so as to be slidable up and down on the fusible alloy 62. Further, a disk-shaped lock ball receiving portion 64 is provided on the upper portion of the piston 63, and the outer diameter thereof is formed slightly smaller than the inner diameter of the upper portion of the ball support cylinder 31. Further, the outer periphery of the lock ball receiving portion 64 is formed with a two-step inclined surface having different inclination angles, and a tapered surface with which the lock ball 71 abuts is provided.

  The lock ball 71 is made of a steel material or the like, enters the insertion hole 32 of the ball support tube 31, and comes into contact with the groove portion 8 of the head main body 1 and the taper surface of the lock ball receiving portion 64, so that the thermal decomposition mechanism 30 is moved to the head main body 1. Further, it is prevented from leaving the frame 10.

  The heat sensitive plate 42 is a disc whose central portion is bent into a truncated cone shape, and a connecting hole 43 is provided in the central portion. The upper portion 44 is fixed by caulking to the bottom surface of the cylinder 41, and the inclined surface 45 is formed. It is bent so as to incline toward the fusible alloy 62 accommodated in the cylinder 41. The lower part 46 of the heat sensitive plate 42 is formed substantially horizontally and extends to the lower side of the guard member 35. Further, a predetermined gap (thermal airflow space) is provided between the lower portion 46 of the heat sensitive plate 42 and the lower end of the guard member 35. In the present embodiment, the case where the number of the heat sensitive plates 42 is one will be described.

  The guard member 35 is a substantially cylindrical body, the outer diameter of the upper portion thereof is reduced, the outer diameter is formed smaller than the inner diameter of the step portion 12 of the frame 10, the inner diameter of the upper portion thereof is reduced, and the ball support cylinder 31. A screw part to be screwed is formed. Further, a stepped portion whose diameter is expanded on the lower side is provided on the outer peripheral side of the guard member 35, and a contact portion 37 that contacts the lower surface of the stepped portion 12 of the frame 10 in the vertical direction is formed. The lower side of the contact portion 37 is formed in a tapered shape that tapers downward. The height of the guard member 35 is selected such that the lower end of the guard member 35 is below the fusible alloy 62 and above the lower portion 46 of the heat sensitive plate 42 when screwed with the ball support cylinder 31. It is. Further, the guard member 35 is provided between the ball support cylinder 31 of the thermal decomposition mechanism 30 and the frame 10 coupled to the head main body 1 so as to close the gap between the two, that is, has a width for closing the gap between the both. And the inside of the frame 10 is sealed.

The lower end of the support column 23 is in contact with the upper surface of the guard member 35.
The lower side of the guard member 35 has a shape having a recess so that a space is formed around the fusible alloy 62. This promotes the melting of the fusible alloy 62, which is a heat-sensitive element, in which the hot air current tends to stay in the recess.

  In the sprinkler head as described above, the valve body 15 seals the water discharge port 2 of the head main body 1 with an assembly load to prevent water leakage, and this assembly load is transmitted to the lock ball 71 via the ball support cylinder 31. Acts downward. The lock ball 71 is pressed against the tapered surface of the groove 8 of the head body 1 by this load. For this reason, the lock ball 71 is always subjected to a force to enter the inside of the ball support cylinder 31. However, since the lock ball 71 is prevented from moving by the contact surface of the lock ball receiving portion 64 of the piston 63, the lock ball 71 is held at that position and locks the ball support cylinder 31.

Next, the operation of this embodiment will be described.
FIG. 9 shows a case where the sprinkler head is in a warning state. Pressurized fire-extinguishing water is supplied to the water outlet 2 of the head body 1, and the pressure of the fire-extinguishing water is applied to the valve body 15. Yes.
Now, when a fire occurs, the hot airflow flows along the lower surface of the ceiling plate (not shown) from the side or from below to heat up against the heat sensitive plate 42, and the heat is transmitted to the cylinder 41. The fusible alloy 62 accommodated in the cylinder 41 begins to be heated and melted from the surroundings, and the melted fusible alloy 62 flows out between the cylinder 41 and the piston 63 to reduce its volume.
At this time, as indicated by the arrows in FIG. 9, the hot airflow from the lateral direction heats the heat sensitive plate 42, and in a gap (thermal airflow space) between the lower portion 46 of the heat sensitive plate 42 and the lower end of the guard member 35. It flows in, rises along the inclination of the inclined surface 45 and directly hits the cylinder 41 to heat the cylinder 41. Further, the hot airflow from below also rises along the lower surface side of the inclined surface 45 and heats the lower surface side of the cylinder 41. For this reason, the fusible alloy 62 is provided above the lower end portion of the guard member 35, and the heat receiving efficiency is improved even if the fusible alloy 62 is not provided outside the sprinkler head. Melt with.

  When the soluble alloy 62 melts and its volume decreases, the lock ball receiving portion 64 of the piston 63 descends as shown in FIG. As a result, the lock ball 71 is released from the groove 8 of the head main body 1 and enters the inside of the ball support tube 31 to unlock the ball support tube 31.

Then, as shown in FIG. 11, the thermal decomposition mechanism 30 is lowered by its own weight and the water pressure of the fire extinguishing water, and is detached from the frame 10 and dropped. At the same time, the deflector assembly 20 including the valve body 15 also falls due to its own weight and the water pressure of the fire extinguishing water, and the stopper ring 25 is seated on the step portion 12 of the frame 10 and stopped. At this time, the valve body 15 is guided by the ball support cylinder 31 and descends and is seated on the deflector 21. As a result, the water outlet 2 of the head body 1 is opened, and the fire extinguishing water is sprayed from the deflector 21 to extinguish the fire.
By the way, in the sprinkler head as described above, when the guard member 35 is not provided, the fusible alloy 62 protrudes from the lowermost end of the frame 10 or the ball support cylinder 31. For this reason, when an external impact is applied to the thermal decomposition mechanism 30 including the fusible alloy 62, the thermal decomposition mechanism 30 may be damaged and malfunction or fire extinguishing water may leak. Further, an external force applied to the thermal decomposition mechanism 30 is applied to the valve body 15 via the ball support cylinder 31, and the valve body 15 may be damaged or deformed, causing malfunction or fire extinguishing water to leak.

  In the first embodiment, a guard member 35 that is screwed into the ball support cylinder 31 is provided, and the lower end thereof is located below the fusible alloy 62 and is located on the outer periphery of the fusible alloy 62 and receives external force. I am doing so. For this reason, the thermal decomposition mechanism 30 including the fusible alloy 62 and the valve body 15 supported by the same can be made less susceptible to external forces. Therefore, the thermal decomposition mechanism 30 including the fusible alloy 62 and the valve body 15 supported by the thermal decomposition mechanism 30 can be prevented from being destroyed or deformed by an external impact, and malfunction and water leakage are less likely to occur.

  Further, the guard member 35 is provided with a contact portion 37 that contacts the step portion 12 of the frame 10 so that the external force received by the guard member 35 is transmitted to the frame 10. For this reason, the external force received by the guard member 35 is less likely to be applied to the thermal decomposition mechanism 30 or the valve body 15, and the thermal decomposition mechanism 30 including the fusible alloy 62 and the valve body 15 supported thereby are destroyed by external impact. Alternatively, deformation can be prevented to make it difficult to cause malfunction or water leakage.

  The guard member 35 has an inner peripheral surface screwed into the ball support cylinder 31 and an outer peripheral surface abutted against the frame 10 by the abutting portion 37 to close the gap between the thermal decomposition mechanism 30 and the frame 10. 10 is sealed inside. For this reason, since the inside of the frame 10 (and the head body 1) has a sealed structure, the lock ball 71, the soluble alloy 62, and the like of the thermal decomposition mechanism 30 may be corroded even when installed in a highly corrosive atmosphere. Absent.

  Further, by providing the guard member 35 on the inner side of the frame 10, it is possible to receive an external force closer to the fusible alloy 62, and to prevent the thermal decomposition mechanism 30 including the fusible alloy 62 from receiving the external force. it can.

Moreover, even if it is a case where the above guard members 35 are provided and the soluble alloy 62 is located above the lower end part of the guard members 35, the inclined surface which inclines the heat sensitive plate 42 toward the soluble alloy 62. 45, the hot airflow flows into the gap between the lower portion 46 of the heat sensitive plate 42 and the lower end of the guard member 35, rises along the inclination of the inclined surface 45, and directly hits the cylinder 41. Thus, the cylinder 41 can be heated. Therefore, even if the fusible alloy 62 is not provided outside the head, the heat receiving efficiency can be improved.
In the present embodiment, the case where the guard member 35 is screwed into the ball support cylinder 31 has been described. However, the present invention is not limited to this, and the guard member 35 may be integrally formed with the ball support cylinder 31. good.

[Embodiment 2]
FIG. 12 is an external view according to Embodiment 2 of the present invention.
Hereinafter, although the sprinkler head according to the second embodiment of the present invention will be described, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 12, the guard member 35 according to the second embodiment has a notch 38 communicating with the inner and outer surfaces on the lower end side.
With such a configuration, as in the first embodiment, the thermal decomposition mechanism 30 including the fusible alloy 62 and the valve body 15 supported by the thermal decomposition mechanism 30 can be hardly affected by external force. Furthermore, by providing the notch 38, it becomes easy for the hot air flow to flow between the heat sensitive plate 42 and the guard member 35, and the heat receiving efficiency can be further improved. Therefore, it is not necessary to bend the heat sensitive plate.

  Instead of the notch 38, an opening that communicates the inner and outer surfaces may be provided on the lower end side of the guard member 35. The same effect can be obtained by this.

[Embodiment 3]
FIG. 13 is an external view according to Embodiment 3 of the present invention.
Hereinafter, the sprinkler head according to the third embodiment of the present invention will be described, but the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 13, the guard member 35 according to the third embodiment extends the lower end of the frame 10 to substantially the same position as the lower end position of the fusible alloy 62, and integrally forms the guard member 35 on the frame 10. .
With this configuration, as in the first embodiment, the thermal decomposition mechanism 30 including the soluble alloy 62 and the valve body 15 supported by the thermal decomposition mechanism 30 can be made less susceptible to external forces. It is possible to prevent malfunction or water leakage by preventing breakage or deformation due to external impact of the thermal decomposition mechanism 30 including the valve body 15 and the valve body 15 supported by the mechanism.

[Embodiment 4]
In the fourth embodiment, the case of other shapes will be described.
Hereinafter, the sprinkler head according to the fourth embodiment of the present invention will be described, but the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

FIG. 14 is a plan view of a thermal plate according to Embodiment 4 of the present invention.
In the first embodiment, the inclined surface 45 of the heat sensitive plate 42 is formed on the truncated cone, and the hot air flow is raised along the inclination of the inclined surface 45, but a part of it detours in the outer peripheral direction.
As shown in FIG. 14A, the heat sensitive plate 42 according to the fourth embodiment forms the inclined surface 45 in a truncated quadrangular pyramid shape.

With such a configuration, the hot airflow hitting the inclined surface 45 of the heat sensitive plate 42 is less likely to bend in the outer peripheral direction, and the hot airflow rising in the direction of the cylinder 41 is increased, so that the heat receiving efficiency can be further improved. .
Further, as shown in FIG. 14B, the inclined surface 45 has a truncated polygonal pyramid shape (for example, a hexagonal pyramid), and the inclined surface 45 serving as the pyramid surface is formed to be curved downward.
With such a configuration, the thermal airflow that hits the inclined surface 45 is less likely to bend in the outer peripheral direction, and the thermal airflow that is bent in the central direction and rises in the direction of the cylinder 41 increases, thereby further improving the heat receiving efficiency. be able to.

[Embodiment 5]
FIG. 15 is a longitudinal sectional view according to Embodiment 5 of the present invention.
Hereinafter, the sprinkler head according to the fifth embodiment of the present invention will be described, but the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.
As shown in FIG. 15, the heat sensitive unit 40 according to the fifth embodiment further includes a heat sensitive plate 42b below the heat sensitive plate 42a.

  With such a configuration, as indicated by the arrows in FIG. 15, the hot airflow that flows in from the lateral direction heats the thermal plate 42a and the thermal plate 42b, and on the inclined surfaces 45a and 45b of the thermal plate 42a and the thermal plate 42b. Each of them rises along the inclination and directly hits the cylinder 41 to heat the fusible alloy 62 under the cylinder 41. Thereby, the heat receiving efficiency can be further improved.

In addition, in each embodiment, although demonstrated using the sprinkler head provided with both the heat sensitive board which has an inclined surface, and a guard member, these should just be provided with either one. The thermal decomposition mechanism has been described as using a ball. However, the thermal decomposition mechanism is not limited to the ball, and the thermal decomposition mechanism may be configured by a link mechanism using a pair of levers. Any other thermal decomposition mechanism may be used as long as it decomposes or bursts in the event of a fire.
In addition, the guard member is positioned on the outer periphery of the thermal element, but this does not have to be the entire periphery, and may guard only the outer peripheral portion in a specific direction. In addition, the thermal plate only needs to be formed as a result of an inclined surface for flowing a hot air flow toward the thermal element, and is not bent. For example, a flat thermal plate and an inclined thermal plate are welded together. They may be joined and integrated.

DESCRIPTION OF SYMBOLS 1 Head body, 2 Outlet, 3 Thread part, 4 Flange, 5 Thread part, 6 Cylindrical part, 7 Hole, 8 Groove part, 9 Outlet edge, 10 Frame, 11 Female thread part, 12 Step part, 15 Valve body , 20 Deflector assembly, 21 Deflector, 23 Strut, 25 Stopper ring, 30 Thermal decomposition mechanism, 31 Ball support tube, 32 insertion hole, 35 Guard member, 37 Abutting part, 38 Notch, 40 Thermal part, 41 cylinder, 42 Heat sensitive plate, 43 connecting hole, 44 upper part, 45 inclined surface, 46 lower part, 51 main body part, 52 head part, 53 upper surface, 54 step part, 62 fusible alloy, 63 piston, 64 rock ball receiving part, 71 rock ball.

Claims (3)

A sprinkler head comprising a head body having a water outlet, a valve body that closes the water outlet, and a thermal decomposition mechanism that supports the valve body ,
The thermal decomposition mechanism is a sprinkler head comprising a thermal element and a thermal plate that is integrally fixed and fixed downward so as to propagate heat to the thermal element .
Located below the thermal element and on the outer periphery thereof, and provided with a guard member that receives external force, the thermal plate is provided below the guard member,
The heat sensitive plate is bent so as to have a disc-shaped outer peripheral portion whose outer diameter is less than the outer diameter of the head body, and an inclined surface inclined toward the heat sensitive element inside the outer peripheral portion . Sprinkler head characterized by that.   2. The sprinkler head according to claim 1, wherein the guard member is formed in a cylindrical shape, and an opening or a cutout that communicates the inner and outer surfaces is provided on the lower end side of the guard member. A sprinkler head comprising a head body having a water outlet, a valve body that closes the water outlet, and a thermal decomposition mechanism that supports the valve body,
The thermal decomposition mechanism is a sprinkler head comprising a thermal element and a thermal plate that is integrally fixed and fixed downward so as to propagate heat to the thermal element.
The heat sensitive plate has a disk-shaped outer peripheral portion whose outer diameter is less than the outer diameter of the head body, and a thermal airflow from the side or below due to a fire flows toward the heat sensitive element inside the outer peripheral portion. sprinkler head characterized by having a an inclined surface inclined toward the heat-sensitive element as.