This present invention relates to a hydrant. Hydrants are connected to a water distribution system and represent a water-dispensing fitting to enable the fire brigade as well as public and private users to withdraw water from the public water distribution system. The mains pressure in the water distribution system is typically approx. 6 to 9 bar. Hydrants are generally differentiated between surface hydrants and underground hydrants. The surface hydrant is permanently installed above ground and has outlets with standardized couplings. The underground hydrant is installed underground and covered by a ground cover from above. Thus, the underground hydrant is a water withdrawal point located below ground level, which is closed off by the ground cover. Hydrants comprise a riser pipe with an interior and an exterior, with the interior opening into the connection for water extraction. To open and close hydrants, they are equipped with a shut-off device located in the area of a bottom-side inlet pipe. As long as the shut-off element is in the closed position, the interior of the riser pipe is sealed against frost from the hydrant inlet.
To open or close the shut-off element, a spindle, which is arranged essentially axially in the hydrant, is turned over manually. By turning the spindle, this rotation is transferred to a spindle nut, whereby the section of the spindle running axially in the hydrant, also called valve rod, is guided axially up and down. The shut-off element is arranged below the so-called frost line, so that the water does not freeze. In the state of the art, measures are known which, after closing the shut-off element, concern the drainage of water from the interior of the riser pipe so that the interior of the riser pipe is free of water which could otherwise freeze in it. The drainage of water from the interior of the riser pipe should prevent damage to the hydrant caused by freezing water. Draining the water from the interior of the riser pipe also serves to reduce corrosion inside the hydrant and to prevent the formation of germs in the stale water. Slide hydrants are also known, in which the shut-off device comprises a slide and sealing surfaces interacting with it, into which the slide is pushed for shut-off.
The printed publication U.S. Pat. No. 3,858,599 discloses a hydrant with a drain device for draining water from the riser pipe of the hydrant after the shut-off element has closed. The disclosed drain device comprises a drain pipe located in the riser pipe and above the shut-off element, which, after the shut-off element has closed, connects the interior of the riser pipe to its outside and opens into a gravel bed. This should allow the water to be drained off with a reduced risk of clogging.
In the state of the art, one problem is that drainage systems for draining the interior of the riser pipe can become clogged and therefore only insufficient drainage takes place. The blockages may be due to a blockage of the outlet of the respective drainage pipes, for example by compacting the soil in the section of the outlet of the drainage pipe. There is also a risk that the drainage pipe will freeze up completely or at least partially if, for example, it is not properly laid below the frost line. It is also disadvantageous that it is not always ensured that the soil in the area of the riser pipe of the hydrant has the necessary permeability to reliably drain off the required amount of water from the riser pipe. In the state of the art, the water flows out of the riser pipe only through the pressure of the water column in the interior. Another problem in the state of the art is that at a high groundwater level there is an unwanted return flow of water from the ground into the interior of the riser pipe, thereby filling the riser pipe with impure water. A high groundwater level can be found near lakes, rivers or water bodies in general. The groundwater level can rise, for example, due to heavy rainfall. In addition to the aforementioned danger of water freezing, there is thus a further danger of germ formation in the interior of the hydrant. This can cause germs to come into contact with fresh water from the water distribution network. When the hydrant is used, germ-contaminated water is ejected, which can endanger the health of humans and animals. It is therefore the object of the present invention to propose a hydrant whose riser pipe can be reliably drained.
This object is achieved by a hydrant according to the independent claim 1. Other advantageous features result from the dependent claims.
According to the invention, the aforementioned object is achieved by a hydrant which comprises a riser pipe with an interior and an exterior and a shut-off element which can be brought from at least one open position into at least one closed position and vice versa, and wherein the shut-off element is designed in the closed position such that the interior of the riser pipe can be sealed against a hydrant inlet. The hydrant further comprises at least one first passage through which the interior of the riser pipe can be fluidly connected to the exterior of the hydrant, and one second passage through which the pressurized hydrant inlet can be fluidly connected to the exterior of the hydrant, wherein the first and second passages can be brought into operative connection with one another, wherein this operative connection generates a vacuum by means of water flowing through the second passage, so that water present in the interior of the riser pipe is discharged via the first passage and the riser pipe is thereby drained.
Advantages of the present invention comprise:
The water inside the riser pipe is reliably ejected from the hydrant inlet by means of the Venturi principle through the pressurized water. This ensures that the riser pipe is reliably emptied by means of a strong vacuum.
The construction is particularly simple and does not require complex components, so that the drainage of the riser pipe is highly reliable.
The drainage of water from the interior of the riser pipe takes place particularly quickly.
After drainage of the riser pipe, the passages can be closed. This prevents water from the ground from flowing back into the interior of the riser pipe. Thus, the interior of the riser pipe is not contaminated with contaminated water.
Drainage is carried out by means of a generated strong vacuum, so that drainage is possible even when the groundwater level is higher than the water level in the interior of the riser pipe.
The jet pump is integrated in the hydrant. This eliminates the need for cumbersome and lengthy work to lay drainage pipes and possibly other external components. No further extensions are necessary.
The drainage system of the hydrant is particularly easy to operate.
The drainage system can be retrofitted to many types of hydrants. Furthermore, the drainage device can be used with almost all types of shut-off elements.
Hydrants already installed in the field can be retrofitted with the drainage device of the hydrant according to the invention.
Drainage can be accelerated by providing several jet pumps to a drainage device in the lower part of the riser pipe. The jet pumps can be arranged at a certain angular distance from each other.
Drainage can be controlled manually or electrically, e.g. with the aid of an actuator. The actuator can include an electrically or mechanically controllable valve. This allows the passages to be opened and closed particularly reliably.
Drainage can be carried out by turning a hydrant valve rod, which is normally used to open and close the shut-off element, to a predetermined rotary position.
The hydrant according to the invention is explained in more detail by means of exemplary embodiments and corresponding drawings, which are not intended to limit the scope of the present invention, wherein:
Preferred embodiments of the hydrants according to the invention are described in detail below.
Shut-off element 108 comprises a main valve body 110 and at least one component of hydrant 100 having a sealing surface and cooperating therewith for shut-off. Shut-off element 108 is generally a valve with the main valve body 110, which can be brought into contact with the sealing surfaces of hydrant 100. The main valve body 110 can be moved axially in relation to the other interacting components of the shut-off element 108 by means of an axially arranged drive device 111, which is designed as a valve rod, for example. To close the hydrant 100, the main valve body 110 is transferred to the upper valve position shown in
For a more detailed explanation of the drainage of hydrant 100 according to the invention, reference is now made to
For this purpose, the hydrant 100 comprises a first passage 114′, 114″, via which a fluid connection can be produced between the interior 104 of the riser pipe 102 and the outside of the hydrant 100. As shown in
To discharge the water from the interior 104 of the riser pipe 102, a second outlet 116′, 116″ is also in fluid connection with the hydrant inlet 106, also only in the drainage position shown in
In the following reference is made in detail to the jet pump 113′, 113″. The jet pump 113′, 113″ comprises a vacuum chamber 118′, 118″ which connects to the second outlet 116′, 116″ and leads outwards. The vacuum chamber 118′, 118″ can be subjected to negative pressure by the water flowing out of the hydrant inlet 106 via the second outlet 116′, 116″ under pressure (jet pump principle or Venturi principle). The vacuum chamber 118′, 118″, which is subjected to a negative pressure, is in fluid connection with the interior 104 of the riser pipe 102 via the first passage 114′, 114″. Thus, the water is reliably sucked out of the interior 104 of the riser pipe 102 by means of generated vacuum and discharged to the outside.
In the open position of the hydrant 100 shown in
At the inlet of the jet pump 113′, 113″, a water jet flows under full line pressure from the hydrant inlet 106 via the second passage 116′, 116″ into the vacuum chamber 118′, 118″. The vacuum chamber 118′, 118″ has a larger diameter than the second passage 116′, 116″. Between the fast flowing water jet and the surrounding water from the riser pipe 102 a mixing of the media occurs, whereby kinetic energy from the water jet from the hydrant inlet 106 is transferred to the surrounding water from the riser pipe 102 and thus a conveying mechanism is provided. The ejection of the medium creates a vacuum in the vacuum chamber 118′, 118″, whereby the water to be pumped from the riser pipe 102 flows in through the vacuum connection.
By means of a surprisingly simple solution, the water from the interior 104 of the riser pipe 102 is ejected to the outside by the pressurized water from the hydrant inlet 106 via the jet pump principle or Venturi principle. This ensures that the water in the riser pipe 102 is discharged to the outside particularly quickly and reliably. In the first variant of the first embodiment shown in the
In the drainage position shown in
In the first variant of the first embodiment shown in
As mentioned above, the jet pump 113′, 113″ is designed to discharge the water from the interior 104 of the 102 riser pipe by direct admission through the water supplied at the hydrant inlet 106 to the outside. In the first variant of the first embodiment, an actuator is provided which only establishes a fluid connection between the interior 104 of the riser pipe 102 and the outside of hydrant 100 and between the hydrant inlet 106 and the outside of hydrant 100 in the drainage position. In the first variant of the first embodiment shown in
In the exemplary embodiment described above, the jet pump 113′, 113″ is designed to discharge the water from the interior 104 of the riser pipe 102 to the outside by means of direct admission through the water supplied from the hydrant inlet 106.
Although not shown, the riser pipe 102 of hydrant 100 described as an example in the embodiment described (and also in the further embodiments described) may include a ventilation opening (not shown) which compensates for a pressure difference between the interior 104 of the riser pipe 102 and the outside of the hydrant 100 when the riser pipe 102 is drained. This prevents a vacuum in the interior 104 of the riser pipe 102, which counteracts the ejection of water to the outside of the hydrant 100. The hydrant may also include an indicator device (not shown) to provide the operator with an indication of the water level in the interior 104 of the 102 riser pipe. For example, the indicator device may be operatively connected to the ventilation opening and comprise at least one oscillating body which generates an audible oscillation when air flows over and/or through it. When the riser pipe 102 is drained, a vacuum is created which is compensated by the ventilation opening. Air flows in from outside into the interior 104 of the riser pipe 102. The vacuum is generally generated in the drainage position of hydrant 100. In the drainage position of hydrant 100, the vacuum can be generated even if the riser pipe 102 has already been drained. The air flow can excite the oscillating body contained in the indicator device to an audible oscillation. As long as the oscillating body generates an audible vibration, the operator is informed that the hydrant 100 is (still) in the drainage position. This at least reminds the operator to transfer the hydrant 100 to the closed position (
The second variant differs from the first variant in terms of the actuator design. Furthermore, only one jet pump 113 is shown here. In the second variant of the first embodiment, the actuator comprises electrically controllable valves 120′, 120″ which release or block a fluid connection between the interior 104 of the riser pipe 102 and the jet pump 113 as well as a fluid connection between the hydrant inlet 106 and the jet pump 113. More precisely, the first electrically controllable valve 120′ either releases or blocks a fluid connection between the riser pipe 102 and the jet pump 113. Furthermore, the second electrically controllable valve 120″ is designed to enable or disable a fluid connection between the hydrant inlet 106 and the jet pump 113. Both electrically controllable valves 120′, 120″ can be controlled via an electrical control unit 122. The electrically controllable valves 120′, 120″ are each connected to the electrical control unit 122 via a signal connection 124′, 124″. The signal connection 124′, 124″ can be an electrical signal line (cable) or a radio connection (wireless connection).
In the valve position shown in
As previously mentioned, control unit 122 switches the two electrically controllable valves 120′, 120″ to their closed position as soon as the riser pipe 102 is drained. The two electrically controllable valves 120′, 120″ can be actuated essentially simultaneously for opening and closing during the transition to the drainage position. It is advantageous to first block the first passage 114 and then block the second passage 116 when changing from the drainage position to the closed position. In other words, the first valve 120′ is controlled first for closing and then the second valve 120″ for closing. This prevents water from flowing back towards the interior 104 of the riser pipe 102. The changeover can be controlled via a time control, which can, for example, be included in the control unit 122. In an alternative example, the control unit 122 can control the two electrically controllable valves 120′, 120″ for closing, as soon as an empty condition of the riser pipe 102 is detected via a float (not shown), which serves as a sensor. In another example, a sensor 126 may be installed in or on the first passage 114, which can establish the fluid connection between the interior 104 of the riser pipe 102 and the jet pump 113, which transmits an indication of the water conveyed to the control unit 122. The sensor 126 is connected for this purpose to the control unit 122 via a signal connection 128. The signal connection 128 can be an electrical signal line or a radio connection. As soon as sensor 124 detects that the first passage 114 is no longer carrying water, as the riser pipe 102 has meanwhile been completely drained, the control unit 122, based on this detected condition, will block the two electrically controllable valves 120′, 120″.
In an example not shown here, only one electrically controllable valve can be provided which opens or closes the two passages 114, 116 simultaneously or shortly in succession. For example, this valve can also be located in the main valve and close or release at least one corresponding hole in the main valve. Instead of the electrically controllable valves 120′, 120″ described here, at least one mechanically controllable valve (not shown) can also be provided.
In the second variant of the first embodiment shown in
In the drainage position, a turbine wheel 132 contained in the centrifugal pump 130 is acted upon and reversed by the water flowing under pressure from the hydrant inlet 106. A shaft 134, axially connected to the turbine wheel 132, projects into a vacuum chamber of the centrifugal pump 130 and allows the water flowing in through the first outlet 114 from the riser pipe 102 to flow radially outwards by means of centrifugal force. The water flows in this case into a ring chamber 136 and is discharged thereby to the outside. The first 114 and second 116 passages are opened and closed via a sliding device 138 (valve device) shown schematically. In the variant shown, the first 114 and second 116 passages are blocked via the sliding device 138. By moving the sliding device 138 upwards, the first 114 and second 116 passages are opened. The first 114 and second 116 passages can alternatively be opened and closed via electric valves (not shown).
In the illustrated embodiment, the main valve seat of the hydrant 200 is designed as a changeover valve seat 222 which can be inserted into and removed from the hydrant 200. The main valve body 210 can be transferred from at least one open position to at least one closed position and vice versa by means of a drive device 211 in relation to the changeover valve seat 222. In the second embodiment, the drive device 211 is designed as an axially movable valve rod. The changeover valve seat 222 is provided at a portion thereof (shown in
The changeover valve seat 222 is of annular design and comprises at least two grooves introduced circumferentially on the outer surface for receiving an annular seal 228′, 228″ each, which seals the interior 204 of the riser pipe 202, the passage space 226 and the hydrant inlet 206 against each other. The changeover valve seat 222 also includes a second passage 216 through which the hydrant inlet 206 (in the drainage position shown in
In the second variant of the second embodiment shown in
Although not shown, the first passage 214 can have an unaltered cylindrical cross-section over its length. It is advantageous if the ratio between the inner diameter of the first passage 214 (or between a minimum inner diameter thereof) and a minimum inner diameter of the second passage 216 is equal to 2:1 to 15:1, in particular 3:1 to 4:1. In one embodiment, the minimum inner diameter of the first passage 214 is 8 mm to 19 mm and the minimum inner diameter of the second passage 216 is 2 mm to 2.5 mm. After the interior 204 of the 202 riser pipe has been drained, the main valve body 210 can be moved axially downwards via the drive device 211 to assume the closed position shown in
In the closed position shown in
The main valve body 210 is provided with a main valve body inner conduit (not shown) which establishes a fluid connection between the hydrant inlet 206 and the inlet of the second passage 216 as soon as the main valve body 210 is in the drainage position shown in
According to the second variant of the second embodiment, the advantage is that the hydrant 200 can be brought directly into the drainage position by moving the main valve body 210 upwards, starting from the illustration of the hydrant 200 shown in
In the open position of the hydrant 200 shown in
By moving the main valve body 210 upwards from the open position (
To drain the hydrant 200, the main valve body 210—starting from the closed position (
By turning the main valve body 210 to a predetermined rotary position, passage sections of the main valve body 210 overlap with both the first opening 224′, 224″ and the second passage 216. For example, the aforementioned passage sections may be one or more recesses embedded in the main valve body 210, through which the pressurized water in the hydrant inlet 206 flows into the second passage 216 and through which the water from the riser pipe 202 flows into the first opening 224′, 224″.
In the third variant of the second embodiment shown in
A particular advantage of this embodiment is that the main valve body 210 does not require any further axial height adjustment in order to be transferred to the drainage position. The operator can move the main valve body 210 between two maximum valve positions as usual, namely a fully open position (see
Although not shown, in an alternative example the changeover valve seat 222 can be turned over in relation to the main valve body 210 mounted in a torsionally rigid manner. As clearly shown in
In the slide position shown in
In the slide position of the hydrant 300 shown in
As previously mentioned, the hydrant 300, in the slide position shown in
The same reference numerals indicate the same or corresponding features of the hydrant according to the invention, although reference is not made thereto in each case and in relation to every figure.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2016/053234 | 2/16/2016 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
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WO2017/140346 | 8/24/2017 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
1433110 | Buckler | Oct 1922 | A |
2020071 | Lofton | Nov 1935 | A |
2481909 | Dales | Sep 1949 | A |
3980097 | Ellis | Sep 1976 | A |
4520836 | Hutter, III | Jun 1985 | A |
4653521 | Fillman | Mar 1987 | A |
6085776 | Hoeptner, III | Jul 2000 | A |
Number | Date | Country |
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216 870 | Dec 1909 | DE |
2 781 663 | Sep 2017 | EP |
Entry |
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International Search Report and Written Opinion for PCT/EP2016/053234 filed Feb. 16, 2016. |
International Preliminary Report on Patentability for PCT/EP2016/053234 filed Feb. 16, 2016. |
Number | Date | Country | |
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20190119887 A1 | Apr 2019 | US |