JPH0141806Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a fire hydrant, and more specifically to a fire hydrant that is provided with a means for preventing breakage due to strong pressure when the part buried in the ground freezes.

[Conventional technology]

Since conventional fire hydrants are buried directly in the soil, they are subject to intense external pressure from the surrounding area due to the pressing force caused by the expansion of the soil during freezing, i.e., the upward force caused by the heaving of the ground, etc. Strong internal pressure was generated due to freezing and expansion of residual moisture above the valve body inside the fire hydrant, and there was no function to prevent these internal and external pressures.

[Problem that the invention attempts to solve]

As mentioned above, fire hydrants are damaged due to the strong internal and external pressure that occurs when it freezes, and repairing them involves excavating frozen land, which requires a great deal of labor, time, and expense, and in the event of an emergency such as a fire. It becomes unusable due to freezing or damage.

In view of the current situation, this invention solves these problems and prevents damage to fire hydrants caused by freezing.
Furthermore, by providing a means for preventing internal residual water from freezing, it is possible to provide a fire hydrant that does not suffer from interference from the soil and does not cause trouble even when it freezes.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides a cylindrical body that fits on the outside of the fire hydrant, and also installs it inside the cylindrical body at an appropriate position on the outer circumferential surface of the hydrant to facilitate vertical movement of the cylindrical body caused by thawing. A fire hydrant is provided with a rolling or sliding means for sliding.

〔Example〕

Next, a more detailed explanation will be given based on the embodiments shown in the accompanying drawings. Figure 1 shows an embodiment of a fire hydrant in which a cylindrical body 1 is fitted on the outside of the hydrant, and rolling means 2 and 2' are installed inside the cylindrical body 1 and provided on the outer periphery to facilitate vertical movement of the cylindrical body 1. This fire hydrant has a valve box 3 and a short pipe 4 buried below the ground surface, and a main body 5, a rotating main body 6, and a head cover 7 formed above the ground. The short pipe 4 and the main body 5 are connected by bolts, and the main body 5 and the rotating main body 6 are connected by a half ring 8.
They are fastened and connected, and their materials are made of metal materials such as cast iron, cast steel, etc., and the outer surface is made of cast metal,
The internal structure includes a valve body 9 and a lower valve stem 10 connected to the valve body 9, which is fixed to the lower valve stem 10. A valve stem rotation stopper 11 that moves up and down, and a sleeve 12 that is screwed onto the tip of the lower valve stem.
A valve stem receiver 13 for maintaining the rotational height position of the valve stem and receiving the valve stem is fixed to the outer periphery of the sleeve 12, and one side of a dog clutch 14 is fixed to the head of the sleeve 12. is provided with an upper valve rod 15 on the lower part thereof which engages one side of the dog clutch 14 and fixes the other side of the clutch,
The upper part of the valve stem 15 is loosely fitted into the rotating body 6, and has a square head 33 for rotation at its tip. Also valve body 9
A drain hole 17 is provided that penetrates the inside of the fire hydrant peripheral wall from one side of the outer valve seat 16 to the drain port 36 above.

The cylindrical body 1 is made of a pressure-resistant material such as cast iron or hard steel and has a round pipe shape, and the surface is subjected to surface treatment such as zinc plating or chromate treatment to prevent corrosion. It has a diameter that fits loosely on the outside of the fire hydrant, and its length is the length from the top of the outer surface of the valve box 3 to the top surface of the connecting bolt mounting seat 19 between the short pipe 4 and the main body 5 on the ground surface, that is, the length from the ground surface 18. A stopper 20 that is set to have a length that reaches a slightly higher position and that restricts the vertical movement of the cylinder 1 is connected to the connecting bolt mounting seat 21 of the valve box 3 and the short pipe 4 and the lower rolling means 2. During the vertical movement stroke 22 of the cylinder 1
It is positioned and provided in consideration of the following. In this example, the cylinder 1 is a single cylinder as shown in FIG. A space is formed, and furthermore, it is possible to form a heat insulating layer 26 by filling a heat insulating material such as glass wool or styrofoam between the pipes as shown in C.The upper surface between the pipes is covered with a side plate 24, and the lower surface is covered with a stay piece 23. or both sides are connected by a side plate 24 and a heat insulating material is enclosed. In this case, ventilation holes 27 are provided at appropriate positions on the wall surface of the cylindrical body at other positions on the working surface of the rolling means 2, 2'.
are installed at multiple locations. Further, as means for making the vertical movement of the cylinder 1 easier by being inscribed in the cylinder 1, an appropriate number of means, for example, three, are arranged on each outer periphery above and below a distance multiple times the length of the stroke 22 from both ends of the short pipe 4. ~4 locations are provided, and the shape is as shown in Fig. 3D, for example, a stainless steel ball 28 is inserted into the recess 29 and its rolling action facilitates the movement of the cylinder 1, or as shown in Fig. 3E. A ball bearing 30 filled with antifreeze lubricant, a roller bearing, etc. is installed in the concave portion 29, and its rotary action is utilized, or a light metal made of a rectangular body with rounded corners and fixed vertically as shown in F. It is made by utilizing the sliding action of a metal sliding fixing piece 31 made of copper and its alloys or copper and its alloys.

When using the fire hydrant constructed in this manner, the sleeve 12 is rotated by the clutch 14 of the upper valve stem 15 by rotating the square head 33 at the top with a handle spanner or the like, and the screwing means 34 in the sleeve 12 is used to close the lower valve. The rod 10 and the valve body 9 rise, and fire extinguishing water flows from the water main into the upper spout 3.
Water is sprayed from 5 through the hose and nozzle. After use, the square head 33 is rotated in the opposite direction to close the valve, and in order to drain the residual water on the upper part of the valve body 9, the pressure of gas such as automobile exhaust gas is used to back-press the water into the water outlet 35 and drain the water inside. The remaining water is discharged to the upper drain port 36 through the drain hole 17 provided inside the peripheral wall to empty the interior and prevent damage such as bursting due to internal freezing in cold weather.

Furthermore, during the cold season, the cylindrical body 1 is pushed upward due to the swelling of the ground due to freezing. At this time, the cylindrical body 1 climbs onto the inscribed rolling means 2 and 2' and is stably supported internally, as well as Due to rolling and sliding effects, smooth upward movement is possible, and damage to the fire hydrant due to strong surface pressure can be prevented. In addition, during the thawing season, the cylinder 1 naturally descends due to the shrinkage of the land and its own weight, and returns to its original position. Note that the distance of vertical movement of the cylinder 1, that is, the stroke length 22, is set to a slightly longer distance, for example, about 80 mm, assuming that the height of the ground surface rise is about 60 mm on average.

In addition, as mentioned above, the cylinder 1 can be formed into a single cylinder A, a double cylinder B, or even a double cylinder C filled with a heat insulating material, etc., thereby creating a space 37 between the cylinder 1 and the fire hydrant. Alternatively, underground freezing of the fire hydrant is prevented by forming a space 25, a hollow layer 25, and a heat insulating layer 26 inside the double cylinder. Furthermore, by setting the valve body 9 deeper than the center of the water main pipe to prevent freezing of the valve body 9 and its surroundings, and by draining residual water inside the fire hydrant, the inside of the fire hydrant does not freeze and can be used as a conventional fire hydrant. There is no need for heating the upper part or for thawing during use. In addition, in the event of repair, the internal valve body 9 can be removed by removing the mounting bolts of the connection part 19 between the short pipe 4 below the ground surface 18 and the main body 5, and separating it.
It can be salvaged and repaired easily, and there is no need to excavate frozen land like in the past.

[Effect of idea]

The fire hydrant of the present invention, which is constructed as described above, can prevent strong external pressure during freezing due to the externally fitted cylindrical body and means for facilitating its vertical movement, thereby eliminating damage to the hydrant and the cylindrical body. , a space, a heat insulating layer, etc. are formed between the cylinder and the fire hydrant, and a residual water drainage function inside the fire hydrant prevents freezing damage to the above-ground and underground parts, as well as maintenance, inspection, etc.
Repairs and other work can be carried out easily, preventing damage even when frozen, and ensuring that the purpose can be achieved.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the fire hydrant configuration, and Fig. 2 is a cross-sectional view of the cylinder, in which A shows a single cylinder, B shows a double cylinder, C shows a double cylinder filled with heat insulating material, and FIG. 3 is a schematic diagram of the rolling and sliding means, in which D is a spherical rolling means, E is a rotary rolling means using ball bearings, roller bearings, etc., and F is a sliding means using a fixed piece. 1: Cylindrical body, 2, 2': Rolling means, 3: Valve box,
4: Short pipe, 5: Main body, 6: Rotating main body, 7: Lid body,
8: half ring, 9: valve body, 10: lower valve stem,
11: Stopper, 12: Sleeve, 13: Valve stem holder, 14: Engagement clutch, 15: Upper valve stem, 1
6: Valve seat, 17: Drainage hole, 18: Ground surface,
19: Main body mounting seat, 20: Stopper, 21: Short pipe mounting seat, 22: Vertical stroke, 23: Stay piece, 24: Side plate, 25: Space, 26: Heat insulation layer, 27: Ventilation hole, 28: Steel Sphere, 29: recess, 3
0: Ball or roller bearing or roller-shaped body, etc., 31: Fixed piece for sliding, 33: Square head, 3
4: Screwed part, 35: Spout, 36: Drain port, 3
7: Space between the cylinder and the fire hydrant.

Claims (1)

[Scope of utility model registration request] A fire hydrant comprising a cylindrical body into which a fire hydrant is externally fitted, and rolling or sliding means installed inside the cylindrical body at appropriate locations on the outer peripheral surface of the hydrant to facilitate vertical movement of the cylindrical body.