WO2010146283A1

WO2010146283A1 - Fire hydrant and method for securing a fire hydrant

Info

Publication number: WO2010146283A1
Application number: PCT/FR2010/051117
Authority: WO
Inventors: Céline MERCIER; Maurin Lovera; Tanguy Souchon; Anne-Claire Cousin; Jean-Paul Guillaume
Original assignee: Veolia Eau - Compagnie Generale Des Eaux
Priority date: 2009-06-08
Filing date: 2010-06-07
Publication date: 2010-12-23
Also published as: FR2946369A1; FR2946369B1

Abstract

The invention relates to a fire hydrant (10') that includes a hollow body (12'), a main stopper (28) and a maneuvering device (24, 26) for opening or closing the main stopper (28) from the outside. The fire hydrant (10') further includes a free stopper (40) arranged in the hollow body (12') and capable of automatically moving into an opening position when the water pressure in the hollow body (12') is higher upstream than downstream from the free stopper (40), and into a closing position when the water pressure in the hollow body (12') is higher downstream than upstream from the free stopper (40) or when the water flow stops. Characteristically, emergency opening means (60) makes it possible by an external activation to force the passage of the free stopper into the opening position thereof.

Description

Fire hydrant and method of securing a fire hydrant

The invention relates to a fire hydrant, namely a water supply device for fire protection use or delivery of water on the public highway or in a private place. Such a fire hydrant may be in the form of a pole rising vertically above the ground, such as those mounted on sidewalks, a mouth buried in the ground or a socket , for example installed in the common parts of a building.

These fire-fighting equipment are defined in standards NF EN 14384 (fire hydrants) and NF EN 14339 (buried fire hydrants).

In the present patent application, the term "fire hydrant" may therefore designate a fire hydrant or fire hydrant, but also a washing station or a watering terminal.

Such a fire hydrant essentially comprises:

a hollow body intended for the passage of water between an inlet connection and at least one outlet orifice,

a main shutter disposed in the hollow body downstream of the inlet connection and allowing, restricting or severing the flow of water through the hollow body (corresponding to an open, partially open and closed position respectively); the main shutter), and

- A maneuvering device, consisting of a rod and an actuator, connected to the main shutter and whose control allows the opening or closing of the main shutter from the outside.

However, such fire hydrants are not protected against the phenomenon of water return, namely the reversal of the normal direction of water circulation under the effect of a reversal of pressures. This situation is likely to create a flow of water from outside the network to the water supply network.

This phenomenon can occur, for example, in the event of an abnormal pressure drop on the supply network or in the event of back pressure coming from the user network (pump discharge), which can lead respectively to the siphoning of a reservoir placed in downstream or discharge of a polluted liquid in the supply network. Consequently, a very sensitive problem encountered with such a fire hydrant relates to the relatively easy possibility of intentional or accidental introduction, through one of the outlets, of a product, liquid or otherwise, that could pollute the network. drinking water supply.

WO 2007/101272 attempts to overcome these disadvantages by adding, in a fire hydrant, a free shutter forming a secondary valve, consisting of a non-return valve placed downstream of the foot valve, in the tube column forming the hollow body, at the height of the outlet orifice.

This free shutter is a device for controlling the flow from the pipe connected to the water supply network and which prevents any return of water in said pipe. However, this free shutter being mounted around the operating rod and being automatically controlled opening by a sufficient water pressure in the column tube, it follows a risk of blocking the free shutter in its closed position and this preventing the possibility of delivering water, which is particularly critical in the case of a fire hydrant that no longer provides the fire defense function.

The object of the invention is to overcome these drawbacks of the prior art by proposing a fire hydrant equipped with a reliable backflow prevention means in all circumstances. For this purpose, according to the present invention, the fire hydrant is characterized in that it further comprises a free shutter (secondary) placed in the hollow body independently of the operating device and downstream of the main shutter , said free shutter being able to automatically pass from a position of closure to an open position when the pressure of the water in the hollow body is greater upstream than downstream of the free shutter and on the other hand from the open position to the closed position when the pressure of the water in the hollow body is greater downstream than upstream of the free shutter or when the flow of water ceases, and

- emergency opening means allowing, by an activation outside, to force easily and quickly, by emergency unlocking,

Ie passage of the free shutter in its open position regardless of the water pressure in the hollow body.

In this way, it can be understood that, thanks to the invention, the opening of the free shutter is no longer solely controlled by the pressure of the water in the hollow body, but that it can intervene at any time by a external activation. Thus, the emergency unlocking of the free shutter is for example performed during the intervention of the fire department, by a firefighter who would find that despite the opening maneuver of the main shutter, the water would come out. not of the fire hydrant due to a blockage in the closed position of the free shutter.

In doing so, any return of water to the hollow body is prevented while ensuring the exit of the water outside the hollow body (water supply), if necessary, whatever the water pressure in the hollow body .

According to a preferred arrangement, the emergency opening means comprise a control member connected to a control rod on which is mounted the free shutter, the control member being located outside the hollow body and adapted to move under the effect of a percussion from a first inactive position to a second active position in which the control rod is raised and the free shutter is in its open position.

By this arrangement, it is possible to very easily control the emergency opening putting the free shutter in its open position. Indeed, exercise a percussion, for example with a tool such as a mass, is a natural and fast approach, especially in case of fire.

According to one possible implementation, the control member comprises a percussion head mounted articulated on a mechanical device for transmitting motion connected to the control rod and adapted to transform the descent of the percussion head from the first position of the control member, said descent resulting from the percussion received by the percussion head, in a rise of the control rod, whereby the control member passes into its second position and the free shutter is in its position d 'opening. For example, the percussion head is articulated on the first end of a connecting rod pivoting about a horizontal axis, the second end of the connecting rod being articulated on the control rod. Other structures are of course possible for the mechanical transmission device (by means of gears, magnetic elements, etc.).

The present invention also aims to provide a method of securing a fire hydrant for adapting a pre-existing fire hydrant so that it is impervious to the phenomena of return water and can deliver the water reliably.

For this purpose, according to the present invention, there is provided a method of securing a fire hydrant comprising

a hollow body intended for the passage of water between an inlet connection and at least one outlet orifice; a main shutter disposed in the hollow body downstream of the inlet connection and allowing, limiting or blocking the flow of water through the hollow body,

a maneuvering device, comprising a rod and an operating member, connected to the main shutter and whose control allows the opening or closing of the main shutter from the outside, characterized in that it consists in perform the following steps:

- Equipping the hollow body, independently of the operating device and downstream of the main shutter, a free shutter capable of automatically switching from a position of a closed position to an open position when the pressure water in the hollow body is greater upstream than downstream of the free shutter and secondly from the open position to the closed position when the pressure of the water in the hollow body is more important downstream than upstream of the free shutter or when the flow of water ceases, and - provide and set up emergency opening means allowing, by an external activation, to force the passage shutter free in its open position regardless of the water pressure in the hollow body.

Other advantages and characteristics of the invention will become apparent on reading the following description given by way of example and with reference to the appended drawings in which: - Figures 1 and IA show, in section a fire hydrant of the prior art, respectively type "non-shock" and type "shock",

FIG. 2 represents, in section, a fire hydrant of the prior art,

FIG. 3 is a sectional view of a modified fire pole according to a first embodiment of the invention, in the closed position,

FIG. 3 is an enlarged view of the detail HIA of FIG. 3,

FIGS. 4 and 4A are respectively similar to FIGS. 3 and 3A with the fire hydrant in the normal open position,

FIGS. 5 and 5 are respectively similar to FIGS. 3 and 3A with the fire hydrant in the emergency open position, after unblocking the free shutter,

FIG. 6 is a sectional view of a modified fire hydrant according to a second embodiment of the invention, in the closed position,

FIG. 6A is an enlarged view of the detail VIA of FIG. 6,

FIGS. 7 and 7A are respectively similar to FIGS. 6 and 6A with the fire hydrant in the normal open position, and

- Figures 8 and 8A are respectively similar to Figures 3 and 3A with the fire hydrant in the emergency open position, after unlocking the free shutter.

In Figures 1 and 1A, a fire post 10 of the state of the art is illustrated. Such a fire hydrant 10 comprises a hollow body 12 vertical (column tube) and, upstream of the hollow body 12, an inlet connection 16 in the form of an elbow allowing the passage of water from a pipe 14 of the network. water, to one or more outlet openings defined by a nozzle 18 which is closed by a removable cap 20.

This hollow body 12 consists of an upper aerial portion 12a protruding from the ground S, and a buried lower portion 12b, which are attached to one another by connecting flanges located substantially at the level of the surface of the ground S.

The upper part 12a is closed by a cover 22 from which protrudes a maneuvering square, or more generally an operating member 24, forming the free end of an operating rod 26 which extends all along the hollow body.

The other end (lower) of the operating rod 26 carries the main shutter 28 (foot valve) which cooperates with a main seat 30, equipped with a seal 32 and formed in the lower part 12b of the hollow body 12.

The upper part of the operating rod 26 is threaded and cooperates with a bore carried by a cap 34 which closes the upper end of the hollow body 12.

Conventionally, the control of the operating rod 26 by rotating the operating member 24 makes it possible to raise

(or down) the main shutter 28 from which the opening (or closing) of the passage of the water in the hollow body 12. In this way, due to the prior withdrawal of the plug 20, the outlet of the pressurized water is through the outlet to which a pipe, including a fire hose, has been previously connected.

In the case of FIG. 1, the operating rod 26 is in one piece ("non-shock" type fire hydrant) while in the case of FIG. 1k, the operating rod 26 is formed of a upper portion 26a and a lower portion 26b separable from each other substantially at the surface of the ground S.

In the case of a state-of-the-art buried fire hydrant 110 (FIG. 2), essentially the same elements are found with the following differences (when the elements comparable to those of the fire hydrant 10 previously described are mentioned, the reference signs used are increased by a value of 100).

The hollow body 112 is made in one piece and delimits a single chamber buried in the ground S, housing the operating rod

126 and whose upper portion 112a is flared towards the outlet orifice defined by a nozzle 118 directed vertically and adapted to be closed by a removable plug (not shown). So there is no necessarily of mounting by connecting flanges between the upper part 112a and the lower part 112b,

The arrangement of the lower portion 112b of the hollow body 112 is similar to that of the hollow body 12 of the previously described fire post; an inlet connection 116 connects the lower end of the hollow body 112 to a pipe of the water network 114; the lower end of the operating rod 126 carries the main shutter 128 (foot valve) which cooperates with a main seat 130, equipped with a seal 132, and formed in the lower part 112b of the hollow body 112. The nozzle 118 is placed at the same height as the cap 134, under the surface of the ground S, the nozzle 118 and the cap 134 constituting an upper wall closing the hollow body 112. A removable cap (not shown) is able to close the opening outlet nozzle 118. A removable closure plate 136 is flush with the surface of the ground S and covers, protecting them, the nozzle 118 and the maneuvering member (square) 124 for controlling the operating rod 126 .

Referring now to Figure 3 illustrating a first embodiment of the invention applied to a modified fire hydrant 10 '. The buried part of the post 10 'is unchanged with respect to the post 10 of FIG. 1A: this concerns the inlet connection 16, the lower part 12b of the hollow body 12, what it contains (lower part 26b of the stem of maneuver 26, main shutter 28, main seat 30 and seal 32), and the pipe 14 disposed upstream of the pole 10 '.

If the modified fire hydrant 10 'is formed from a "non-shock" fire hydrant 10 in accordance with FIG. 1, it is then necessary to replace the operating rod 26.

The aerial part of the post 10 'has an upper part 12a' of the hollow body 12 'with a deflection of the passage of the water: a part of the elbow-shaped intermediate tube 12c' makes it possible to extend the lower part 12b of the hollow body 12 from the mounting by connecting flanges, and is extended above by a vertical tube portion 12d 'extending the intermediate tube portion 12c', being parallel and offset from the lower portion 12b. In FIGS. 3 to 5, the intermediate tube portion 12c 'and the vertical tube portion 12d' are integral with the nozzle 18 (which allows the outlet of the water after passing through the vertical tube portion 12d ') and a protective tube portion 12e'.

This protective tube portion 12 'surrounds the upper portion of the control rod 26, being separated from the water passage through the wall of the intermediate tube portion 12c' (which has an opening with a seal for the passage of the operating rod 26).

According to the invention, a free shutter 40 is placed in the vertical tube portion 12d ', independently and separate from the operating rod 26. This free shutter 40 consists of a non-return valve which opens under the pressure of the water in the upper part 12a 'of the hollow body 12' and which closes automatically by means of return.

The free shutter 40 may in particular be a non-return valve of the "EA", "EC" or "HA" type within the meaning of standard NF EN 1717. It will be ensured that the choice of the free shutter 40 respects the hydraulic standards of the fire hydrant concerned.

The upper part 12a 'of the hollow body 12' is shown diagrammatically in FIGS. 3 to 5 and may have multiple configurations, in particular to make it possible to ensure the verification and the maintenance of the free shutter 40.

In the case of the first embodiment illustrated in FIGS. 3 to 5, the free shutter 40 is arranged in the following manner (see FIGS. 3A, 4A and 5A): the body 42 of the shutter is mounted to the lower end of a guide rod 44 whose upper section is housed freely in a hollow control rod 45. The return means consist of a helical compression spring 46 surrounding the guide rod 44, from above of the body 42. The upper end of the spring 46 is housed in a bell 48 open in its upper wall (opening 48a) for fixing the lower end 45a of the control rod 45 and allow the passage of the guide rod 44. The lower rim 48b of the bell 48 is retained within a claw 50 in the form of an inverted cut. The bell 48 and the claw 50 are movable in translation relative to each other, an opening 50a formed in the upper wall of the claw 50 allowing the passage of the lower part of the bell 48. The force exerted by the spring 46 tending to push the bell 48 upwards and the valve body 42 up to the seat of the body 42 on the seat 52. The lower flange 50b of the claw 50 is fixed above the body 42 of the shutter 40.

In the closed position of the free shutter 40, the body 42 bears on a seat 52 formed on the inner face of the wall of the vertical tube portion 12 'of the hollow body 12, possibly with the interposition of an annular seal mounted on the periphery of the body 42 of the free shutter 40 or on the seat 52.

In this way, when, after opening the main shutter 28 by rotating the operating member 24, the pressure of the water in the vertical tube portion 12d 'of the hollow body 12 exceeds the restoring force of the spring 46, the free shutter 40 automatically moves from its closed position (Figure 3A) to its open position (Figure 4A) in that the body 42 is raised, the spring 46 is compressed, the bell 48 slides in the claw 50 (see Figures 4 and 4A), and that the guide rod 44 moves by sliding upwards in the control rod 45 which remains stationary.

On the contrary, when the pressure of the water in the vertical tube portion 12d 'of the hollow body 12 decreases and becomes smaller than the restoring force of the spring 46, the free shutter 40 moves from its open position to its closing position.

It is therefore possible, by prior selection of the hardness of the spring 46, to modify the minimum pressure value of the water in the hollow body 12 which causes the opening of the free shutter 40.

Thus, in the first embodiment, the fire hydrant forms a fire hydrant 10 'in which the hollow body 12' is a column tube and the main shutter 28 is a foot valve, the column tube having a buried lower portion 12b centered around the main shutter 28, an elbow-shaped intermediate tube portion 12c 'and a vertical tube portion 12d' extending the intermediate tube portion 12c 'parallel and offset from the portion 12b and in which is mounted said free shutter 40.

We will now describe the emergency opening means 60 which will allow, according to the invention, to unlock the free shutter, if there was a blockage of the latter (for example the body 42 which remains stuck on the seat 52) preventing its opening. A control member, formed of a percussion head 62, is slidably mounted in a opening 22a 'of the cover 22' which closes the upper part 12a 'of the hollow body 12, the enlarged upper part of the percussion head 62 projecting outwards. The lower end of the percussion head 62 is adapted to come into contact with the first end 64a of a connecting rod 64 pivoting about a horizontal axis 66 mounted in an opening of the cap 34 '. The second end 64b of the rod 64 is articulated on the upper end 45b of the control rod 45.

In this way, as can be seen in FIGS. 5 and 5A, thanks to the connecting rod 64 which forms a lever arm, by a simple percussion exerted on the enlarged upper part of the percussion head 62 (arrow 63), the movement descending from the percussion head 62 is transformed into an upward movement of the control rod 45, resulting in the raising of the bell 48 and, when the rim 48b of the bell has come into abutment against the open upper wall of the claw 50, the rise of the bell 50 and the body 42 attached thereto. The rise of the body 42 corresponds to the mechanical opening of the shutter 40 (the spring 46 is not compressed). In this case, in the presence of a sufficient water pressure in the hollow body 12, the free shutter 40 remains open and allows the water outlet via the nozzle 18, immediately at the end of the percussion operation .

Furthermore, these emergency opening means 60 allow the automatic closure of the free shutter 40 when the water pressure decreases or the flow of water ceases in the upper part 12a '(for example after closing the main shutter 28), Indeed, the weight of the free shutter 40 tends to close the latter. In addition, it is advantageously provided, in order to compensate for at least the friction forces holding the free shutter 40, the use of a return system 68 comprising (see FIGS. 3A, 4A and 5A) a compression spring tending to bring the first end 64a of the connecting rod 64 upwards, which causes the second end 64b of the rod 64 and the body 42 to be lowered in order to seal the free valve 40. Alternatively, provision may be made a counterweight (case not shown) placed in the extension of the second end 64b of the connecting rod 64. Thus, it is understood that the emergency release of the free shutter 40 does not require special tools, any object allowing the striking being usable,

It is also possible to use other types of emergency opening means 60, that the latter operate by transmitting a downward movement in an upward movement of the control rod 45, or else according to other provisions. ; direct control of the rise of the control rod 45, by a rack system, by a hydraulic system and / or pneumatic and / or electronic and / or magnetic ..,.

In order to be able to detect any inadvertent use of these emergency opening means 60, and thus in particular to ensure better maintenance of the latter, a visual indicator 70 is used for the activation of the emergency opening means 60 capable of from a neutral position, and after said external activation (striking on the percussion head) to pass and remain in a visually remarkable position.

In the case of the first embodiment visible in FIGS. 3 to 5, the visual indicator consists of a control pin 70 housed in a housing 22b 'of the cover 22', this control pin 70 being surmounted by a shutter 72 enclosing the housing 22b 'and able to be broken when the lug 70 rises from its initial neutral position, lowered. This rise occurs by an upward push of the control rod 45, located in the vertical extension of the lug 70, during the activation of the emergency opening means 60.

Thus, the raising of the lug 70 making the latter salient, it continues a visual indication of the activation of the emergency opening means 60, also by the fact that the operculum 72 has been permanently broken (a lid 72 very visually remarkable color can be used).

Thus, according to the first embodiment of the present invention, it is proposed to adapt a fire hydrant 10 of the prior art in which the hollow body 12 is a column tube and the main shutter 28 is a foot valve , the column tube comprising a buried lower portion 12b centered around the main shutter 28, by a securing method in which the column tube is equipped, in a an overhead portion 12 'overlying the lower portion 12b, a bend-shaped intermediate tube portion 12c' and a vertical tube portion 12d extending the intermediate tube portion 12c ', being parallel and offset from Ia lower part 12b, and in which is mounted said free shutter 40.

The second embodiment of the invention which has been implemented for a modified fire hydrant 110 'will now be described in relation to FIGS. 6 to 8 and 6 to 8.

The lower part 112b of the hollow body 112 is unchanged with respect to the mouth 110 of FIG. 2, whether it is the inlet connection 116, which this lower portion 112b contains (operating rod 126, main shutter 128, main seat 130 and seal 132), and the pipe 114 disposed upstream of the mouth 110 '.

The upper portion 112a 'of the hollow body 112' of the modified mouth 110 'comprises a deflection of the passage of the water: an elbow-shaped intermediate tube portion 112c' makes it possible to extend the lower part 12b of the hollow body 12 by deviating The water circuit on the side of the operating rod 126. This intermediate tube portion 112c 'is extended above by a vertical tube portion 112d' which flares upward, parallel and offset from each other. at the bottom 112b with respect to the direction of flow of the water. In FIGS. 6 to 8, the intermediate tube portion 112c 'and the vertical tube portion 112d' are integral with the nozzle 118 (which allows the outlet of the water after its passage in the upper part IHdO and a part This protective tube portion 112 'surrounds the upper portion of the control rod 126, being separated from the passage of the water through the wall of the intermediate tube portion 112c' (which has a opening with seal for the passage of the operating rod 126) According to the invention, a free shutter 140 is placed in the vertical tube portion 112d ', independently and separated from the operating rod 126. This shutter free 140 is constituted by a non-return valve which opens under the pressure of water in the upper part 112a 'of the hollow body 112' and which closes automatically by means of return means. In the case of the second embodiment illustrated in FIGS. 6 to 8, the free shutter 140 also constitutes a non-return valve, which has a structure other than that of the free shutter 40 which has previously been described in relation to the first embodiment.

The free shutter 140 comprises a body 142 formed of a disk mounted at the lower end of a guide rod 144 whose enlarged upper end 144a is housed freely in a cage 148 having a single opening 148 in its lower wall. to allow passage of the guide rod 144, while retaining the enlarged upper end 144a of the guide rod 144. The cage 148 is integral with the lower end 145a of a control rod 145. above the body 142 and below the cage 148 is disposed a flange 150 which is fixedly mounted in a lower portion of the vertical tube portion 112d '. For this purpose, fastening flanges 150a allow mounting of the annular flange 150 on the wall of the vertical tube portion 112d 'of the hollow body 112', while allowing the flange 150 to be bypassed by the water flowing in the hollow body 112 '. The flange 150 widens in its lower part 150b whose edge 150c has a diameter less than or equal to that of the body 142. The body 142 naturally abuts against the edge 150c by means of a helical compression spring 146 mounted around the guide rod 144 traversing the collar 150, and resting on the body 142 and on a disk-shaped retaining plate 15Od fixed inside the lower part 150b of the collar 150 and open at its center for the passage of the guide rod 144.

At rest (Figures 6 and 6A), the spring 146 constrains the body 142 to bear tightly against a seat 152 formed in the wall of the lower portion of the vertical tube portion 112d ', while the enlarged upper end 144a the guide rod is positioned at the bottom of the cage 148. This is the closed position of the free shutter 140. In a conventional manner, as for the free shutter 40 of the first embodiment, the seal is achieved by means of a sealing member, preferably flexible, placed on the body 142 and / or on the seat 152 (for example the body 142 is formed of an elastomer disk or a disc lined with an elastomer seal ). After opening the main shutter 128 by rotating the operating member 124, the pressure of the water coming from the intermediate tube portion 112c 'of the hollow body 112' exceeds the restoring force of the spring 146, The free shutter 140 moves from its closed position to its open position by the fact that the body 142 is raised, the spring 146 compresses (see FIGS. 7 and 7A), that the guide rod 144 moves by sliding up the cage 148 until the enlarged upper end 144a of the guide rod is positioned at the top of the cage 148 which then did not move. On the contrary, when the pressure of the water in the hollow body

112 'decreases and becomes smaller than the restoring force of the spring 146, the free valve 140 moves from its open position to its closed position (the guide rod 144 descends until the body 142 comes into sitting on the seat 152, from which a sealed contact). Thus, in the second embodiment, the fire hydrant forms a fire hydrant 110 'in which the hollow body 112' is a buried chamber comprising a lower portion 112a 'centered around the main shutter 128, a portion elbow-shaped intermediate tube 112c 'and a vertical tube portion 112d extending the intermediate tube portion 112c' parallel to and offset from the lower portion 112b 'and wherein said free plug 140 is mounted.

As can be seen in FIGS. 6 to 8, there are emergency opening means 60 similar to those described above in connection with the first embodiment: a percussion head 62 allows, after removal of the closure plate 136, and by an outer striking (arrow 63 on Ia Figure 8A), to rotate the rod 64 about its horizontal axis 66 by descent of the first end 64a of the rod and simultaneously reassembly of the second end 64b of the rod 64 which is attached to the upper end 145b of the control rod 145.

Thus, as it appears in FIGS. 8 and 8A, the external activation of the emergency opening means 60 makes it possible, by raising the control rod 145, to raise the cage 148 and then the guide rod 144 after its enlarged upper end 144a has abutted on the bottom wall surrounding the opening 148a of the Cage 148, from which it follows the compression of the coil spring 146 and the rise of the body 142, which opens the free shutter 140.

These emergency opening means 60 also allow the automatic closing of the free shutter 40 when the water pressure decreases or the flow of water ceases in the upper part 112a '.

(For example after closure of the main shutter 28), and this preferably by means of a return system 68 (a spiral spring mounted around the axis 66 of the connecting rod 64, has been used in FIGS. ) tending to raise the first end 64a of the connecting rod 64 upwards

In the second embodiment, there is provided a system for preventing activation of the emergency opening means 60 if the main shutter 128 is not at least partially open. For this purpose, as shown in Figures 6 and 7, the operating rod 126 and the control rod 145 are substantially parallel to each other, the operating rod 145 is equipped with locking means 180 preventing the activation of the emergency opening means 60 when the main shutter 128 is closed and allowing the activation of the emergency opening means 60 when the main shutter 128 is at least partially open.

More specifically, it is provided that the blocking means 180 comprise:

a first locking member 182 secured to the control rod 145 (in the form of a locking rod extending substantially horizontally from the control rod in the direction of the operating rod 126) and

a second locking member 184 mounted on the operating rod 126 (for example in the form of a ring surrounding the operating rod 126),

The second locking member 184 is placed above the first locking member 182 so as to block the latter and to prevent the rise of the control rod 145 when the main shutter 128 is closed. In this way, as it appears in FIGS. 7 and 8, after a few turns of rotation of the operating rod 126, the second locking member 184 is sufficiently raised to allow a vertical displacement of the first locking member 182 and a rise of the control rod a distance sufficient to open the free shutter 140 by separation of the body 142 of its seat 152, means of blocking identical or similar to the blocking means 180 described above can of course be provided on the fire post 10 'of the first embodiment shown in Figures 3 to 5.

In the context of the second embodiment, it is also provided, as in the case of the first embodiment, a visual indicator of the activation of the emergency opening means 60.

For this purpose, said visual indicator is also a lug 170 located vertically above the control rod 145, without connection with said control rod 145, and which moves from a lowered position (FIGS. 6 and 7) to a position raising (FIG. 8) under the effect of contact with the control rod 145 which rises during the percussion (arrow 63) exerted on the control member 62.

In the context of the second embodiment, there is further provided retaining means (172, 174) adapted to automatically retain the visual indicator (lug 170) in its raised position and to be disengaged (during a maintenance operation the fire hydrant) to allow the visual indicator (pin 170) to descend to its lowered position.

As can be seen in FIGS. 7 and 8, the retaining means comprise, for example, a lateral notch 172 in the lug 172 which is able to cooperate, in its raised position (FIG. 8A), with the free end of a blade metal 174: then manually remove the metal blade 174 out of the notch 172 to allow the pin 172 to go down. Thus, according to the second embodiment of the present invention, it is proposed to adapt a fire hydrant 110 of the prior art in which the hollow body 112 is a buried chamber having a buried bottom portion 112b centered around the main shutter 128, by a security method in which the buried chamber is equipped, in a portion overlying the lower portion 112b, of an intermediate tube portion 112c 'in the form of elbow and a vertical tube portion 112d 'extending the intermediate tube portion 112c' being parallel and offset from the lower portion (112b) and wherein is mounted said free shutter 140.

It will be understood from the foregoing description of the two embodiments given by way of example that the maintenance and the possible replacement as much of the free shutter 40, 140 as the elements constituting the emergency opening means 60, 160 is greatly facilitated by the fact that they are in the upper part of the fire hydrant (post 10 'or mouth 110'). Moreover, as can be seen in FIGS. 3 to 8, provision is advantageously made to equip the free shutter 40, 140 with an antifreeze drain similar to that of the main shutter 28, 128.

It should be noted that the cover 22 'of the first embodiment or the closing plate 136 of the second embodiment constitute a cover at least partially surrounding the operating device (24, 26 or 124, 126) and the means for emergency opening (60).

Complementarily and optionally, it is possible to further provide in the fire hydrant according to the invention (pole 10 'or mouth 110') a detection system (not shown) of the opening of the main shutter which is able to count the number of openings of said main shutter.

This detection system comprises for example a rev counter (not shown) which counts the number of openings and closures of the main shutter 28 or 128, namely the number of times that the operating member 24 or 124 has has been manipulated in the direction of opening and closing, in particular by rotating the operating rod 26 or 126. This rev counter can be placed on the operating rod 26 or 126, in the tube portion 12d 'or 112d' forming a dry space of the hollow body 12 'or 112'.

This detection system can be associated with a time stamp system, to record the degree and the opening time of the main shutter 28 or 128.

Complementarily and optionally, it is possible to further provide in the fire hydrant according to the invention (pole 10 'or 1100 mouth a detection system (not shown) of the position and movement of the free shutter 40 or 140.

This detection system aims to measure the direction and speed of movement of the free shutter 40 or 140 to deduce its opening and closing mode. Indeed, an upward movement corresponds to an opening and a downward movement corresponds to a closure. Furthermore the speed of movement of the free shutter 40 or 140 also gives information on its operation; a slow movement corresponds to a normal operation, a fast rise signifies an activation of the emergency opening means while a fast descent reflects the activation of the anti-return function following a backpressure and this in order to to prevent any return of water to the pipe connected for example to the water supply network. This detection system comprises for example a first position sensor placed on the control rod 45 and, opposite, at least two position sensors placed on the inner face of the vertical tube portion 12d 'or 112d' of the hollow tube 12 or 112 'and able to cooperate with the first sensor (these sensors can operate according to different techniques and in particular optically, magnetically, electromagnetically or ultrasonically).

It is also possible to provide radio and / or teletransmission means (not shown) capable of remotely transferring, to a central monitoring station, the data of the system for detecting the opening of the main shutter (tachometer). and / or the data of the system for detecting the movement of the free shutter and / or the signaling of the activation of the emergency opening means (locating the pin 70 or 170).

In the latter case, it is anticipated that the fire hydrant further comprises a sensor capable, by detecting the activation of the emergency opening means 60 to emit a corresponding signal, which can be tele-transmitted.

It should be noted that all the features presented in connection with the first embodiment concerning the fire hydrant are adaptable to the second embodiment relating to a fire hydrant and vice versa.

Claims

1. Fire hydrant (10 ', 1100 including

- a hollow body (12 '; 112') for the passage of water between an inlet connection (16; 116) and at least one outlet port; - a main shutter (28; 128) disposed in the hollow body (12 '; 1120 downstream of the inlet connection (16; 116), and allowing, restricting or severing the flow of water through the hollow body (12'; 112%

- an operating device (24, 26; 124, 126) connected to the main shutter (28; 128) and whose control allows the opening or closing of the main shutter (28; 128) from the outside characterized in that it further comprises

a free shutter (40; 140) placed in the hollow body (12 '; 112') independently of the operating device (24,26; 124,126) and downstream of the main shutter (28; 128); said free shutter (40; 140) being adapted to automatically switch from a closed position to an open position when the pressure of the water in the hollow body (12 '; 112') is more than significant upstream than downstream of the free shutter (40; 140) and secondly from the open position to the closed position when the pressure of the water in the hollow body (12 '; 1120 is greater downstream than upstream of the free shutter (40; 140) or when the flow of water ceases, and

- Emergency opening means (60) allowing, by external activation, to force the passage of the free shutter in its open position regardless of the water pressure in the hollow body (12 '; 112 ').

2. Fire hydrant (10 '; 110') according to claim 1, characterized in that the emergency opening means (60) comprise a control member (62) connected to a control rod

(45; 145) on which is mounted the free shutter (28; 128), the control member (62) being located outside the hollow body (12 '; 1120 and able to move under the effect percussion from a first inactive position to a second active position in which the control rod (45; 145) is raised and the free valve is in its open position.

3. Fire hydrant (10 '; 110') according to claim 2, characterized in that the control member comprises a percussion head (62) articulated on a mechanical motion transmission device (64) connected to Ia control rod (45; 145) and adapted to transform the descent of the percussion head (62) from the first position of the control member, said descent resulting from the percussion received by the percussion head (62), at a raising of the control rod (45; 145), whereby the control member passes into its second position and the free shutter (40; 140) is in its open position.

4. Fire hydrant (10 ', IW) according to claim 2 or 3, characterized in that the operating device (24, 26; 124, 126) comprises an operating rod (26; 126), in that the operating rod (26; 126) and the control rod (45; 145) are substantially parallel to each other, in that the operating rod is equipped with locking means (180) preventing the activation emergency opening means (60) when the main shutter (28; 128) is closed and allowing activation of the emergency opening means (60) when the main shutter (28; 128) is at least partially open.

5. Hydrant (1100 according ^'es claims 2 and 4, characterized in that the locking means (180) comprises a first locking member (182) integral with the control rod (145) and a second member lock (184) mounted on the operating rod (126) above the first locking member (182) so as to prevent the rise of the control rod (145) when the main shutter (28; 128) (128) ) is closed.

6. Fire hydrant (10 ', IW) according to any one of the preceding claims, characterized in that it further comprises a visual indicator (70; 170) of the activation of the emergency opening means. (60) adapted from a neutral position and after said external activation to pass and remain in a visually remarkable position,

7. Fire hydrant (10 ', HO ¹ ) according to claims 2 and 6, characterized in that said visual indicator is a lug (70; 170) located vertically above the control rod (45; 145). without connection with said rod control (45; 145), and which moves from a lowered position to a raised position under the effect of contact with the control rod (45; 145) which rises when the control element is struck ( 45, 145).

8. Fire hydrant (HO ') according to claim 7, characterized in that it further comprises retaining means (172; 174) adapted to automatically retain the visual indicator (70; 170) in its raised position and to be disengaged to allow the visual indicator to return to its lowered position.

9. Fire hydrant (10 '; 110') according to any one of the preceding claims, characterized in that said free shutter (40; 140) is a non-return valve

10. Fire hydrant (10 ') according to any one of the preceding claims, characterized in that it forms a fire hydrant in which the hollow body (12'; 112 ^{^} ) is a column tube and the main shutter (28; 128) is a foot valve, the column tube having a buried bottom portion centered around the main shutter (28; 128), an elbow-shaped intermediate tube portion and a vertical tube portion extending the intermediate tube portion being parallel and offset from the lower portion and wherein is mounted said free shutter.

11. Fire hydrant (1100 according to any one of claims 9 to 9, characterized in that it forms a fire hydrant in which the hollow body (12 '; 112') is a buried chamber comprising a lower part. centered around the main shutter

(28; 128), an elbow-shaped intermediate tube portion and an upper tube portion extending the intermediate tube portion being parallel and offset from the lower portion and wherein said free plug is mounted.

12. Fire hydrant (10 '; 1100 according to any one of the preceding claims, characterized in that it further comprises a suitable sensor, by detecting the activation of the emergency opening means (60). to emit a corresponding signal.

13. Fire hydrant (10 '; 110') according to any one of the preceding claims, characterized in that it further comprises a system for detecting the opening of the main shutter (28; 128) which is able to count the number of openings of said main shutter (28; 128).

14. Hydrant (10 '; ¹¹⁰⁰ the ⁿ ° to ^one of the preceding claims, characterized in that it further comprises a position detection system and the movement of the free plug (40; 140).

15. Method for securing a fire hydrant (10 ';

110 ') comprising

a hollow body (12 '; 112') for the passage of water between an inlet connection (16; 116) and at least one outlet orifice;

a main shutter (28; 128) disposed in the hollow body (12 '; 1120) downstream of the inlet connection (16; 116) and allowing, limiting or blocking the flow of water through the body; hollow (12 '; 112'),

- an operating device (24, 26; 124, 126) connected to the main shutter (28; 128) and whose control allows the opening or closing of the main shutter (28; 128) from the outside , characterized in that it consists in carrying out the following steps;

- Equipping the hollow body (12 '; 112'), independently of the operating device (24, 26; 124, 126) and downstream of the main shutter (28; 128), a free shutter adapted to automatically switching from a closed position to an open position when the water pressure in the hollow body (12 '; 1120) is greater upstream than downstream of the free valve and on the other hand from the open position to the closed position when the pressure of the water in the hollow body (12 ', 1120 is greater downstream than upstream of the free valve or when the flow of the water ceases, and - provide and set up emergency opening means (60) allowing, by an external activation, to force the passage of the free shutter in its open position regardless of the pressure of water in the hollow body (12 ';

16, Process according to claim 15 for securing a fire hydrant (100 in which the hollow body (120 ^is a tube) column and the main shutter (28) is a foot valve, the columnar tube comprising a buried bottom portion (12b) centered around the main shutter (28), in which the column tube is fitted, in an aerial part ( 120 overlying the lower portion (12b), an elbow-shaped intermediate tube portion (12c ^* ) and a vertical tube portion (12d ') extending the intermediate tube portion (12C ^, being parallel and offset from the lower portion (12b), and wherein is mounted said free valve (40).

17. The method of claim 15 for securing a fire hydrant (110) wherein the hollow body (1120 is a buried chamber having a lower portion (112b) centered around the main shutter (128), in wherein the buried chamber, in a portion overlying the lower portion (112b), is provided with an elbow-shaped intermediate tube portion (112c ') and a vertical tube portion (112dO extending the intermediate tube portion (112d). 112C ^ n being parallel and offset from the lower part (112b) and in which is mounted said free shutter (140).