SE523144C2 - Tap point and water supply network including such tap point - Google Patents

Abstract

A water tapping point with a hot water inlet (505; 605; 705); a cold water inlet (510 ;610; 710), a hot water space (525 ;625; 825), a cold water space (535 ; 635; 835), a mixing chamber (550; 650; 850), a hot water outlet (555; 755; 855) from the hot water space and a cold water outlet (560; 760; 860) from the cold water space. A characteristic feature of the invention is passage means extending between the hot water outlet and the cold water outlet (655; 704, 660; 706) and provided with means for connection (575; 675; 775) to a common return water pipe (580). The invention also relates to a tap water network comprising a plurality of tapping points. The tap water network needs only one return water pipe.

Description

20 25 30 1523 144 2 manual work and consequently costs for Service Technicians. In addition, in a hospital, for example, the activities at a clinic must be interrupted.

Other attempts to address the problem include purifying the water in, or near, the tapping device.

The methods and devices which include ozone (U.S. Patent Nos. 5,942,125), multiple filters (U.S. Patent No. 5,851,388), bactericides added with a pumping device (U.S. Patent No. 5,709,546) and sterilization by UV light (U.S. Pat. No. 5.89l, 329). These methods and devices are effective in some applications, for example in dental units, but their complexity and maintenance needs make them less suitable for large-scale installations such as any drop-off point in a hospital or in a low-rise building. In addition, the principle of purifying the water at a late stage and not addressing the problem of the rapid bacterial growth itself can be questioned.

In a recently granted U.S. patent, No. 6.02 1,803, by the same applicant as in the present invention, the problems of legionella bacteria are addressed by providing a tapping site which includes a hot and cold water mixer with a hot water and a cold water inlet, and a hot water inlet. and a cold water outlet. To prevent the growth of legionella bacteria in the mixer, it is proposed that the mixer also be provided with a hot water outlet from the hot water space. This outlet is connected to a return hot water line and through a valve arrangement the hot water is kept under constant circulation. This ensures that the water does not cool down to temperatures within the risk range 25-50 ° C. Thermally insulated return water pipes are in fact often installed in the water main network in a building, and if this is the case, the return water pipe only needs to branch to the respective tapping point. This means that the installation and maintenance costs can be kept at a reasonable level.

Traditionally, legionella and other bacteria have been considered a problem mainly in heated water systems. Recently, attention has also been focused on cold water systems.

If cold water is kept immobile for a long period of time, it can be heated up to temperatures in the risk range 25-5 0 ° C, for example during a hot summer day. Another potential risk is that the cold water system is heated by the hot water system. In an ordinary thermostat mixer, for example, the cold water spaces can be heated by thermal conduction from the hot water parts. Similarly, heating by thermal conduction can occur if the cold and hot water pipes are poorly insulated and too close to each other. At temperatures below 10 15 20 25 523 144 - «| Legionella growth is known to be very limited at 18 ° C. To the knowledge of the inventors, there are no known taps that have been designed to reduce heat transport between hot and cold parts.

U.S. Patent No. 6.02 1,803 proposes that cold water be circulated in the same manner as the hot water. This would be an effective way to limit bacterial growth, but it would require a return system even for the cold water. In addition, a water cooling system would be required to prevent continuous heating of the water. There is normally no return water line in the trunks and no water cooling equipment. Such a system would in many cases be too complicated and costly, especially if it is to be installed in already existing buildings.

To summarize what is required to keep leginella growth to a minimum: The hot water should always be kept warm and the cold water should always be kept cold and spaces with immobile water should be carefully avoided. To keep investment and maintenance costs at a reasonable level, the system should not require a completely new backbone network or taps that require frequent maintenance. None of the prior art meets these requirements.

Disclosure of the Invention In conventional tap water networks, the water is allowed, in certain spaces, to be heated or cooled to temperature ranges which entail a risk of bacterial growth. Known solutions to this problem are expensive to install, or require frequent maintenance.

An object of the present invention is to overcome the disadvantages of the prior art by providing a tap water network which effectively prevents bacterial growth in all parts of the network.

Another purpose is to provide a tap water network at reasonable installation and maintenance costs, which effectively prevents bacterial growth.

In order to achieve the above-mentioned system, according to the invention a tapping point is provided which allows continuous circulation of hot water in its hot water parts and continuous circulation of cold water in its cold water parts. 10 15 20 25 1523 .144 n ø n a nu «« | a t: 4 The innovative tapping point provides the opportunity to construct a water network with constant circulation of hot and cold water in all parts of the network. Parts that are not suitable for circulating hot or cold water are evacuated and ventilated.

A realization of the above-mentioned objects and according to a consideration of the invention is a tapping point comprising a hot water inlet, a cold water inlet, a hot water space, a cold water space, a mixing chamber, a hot water outlet from the hot water space and a cold water outlet from hot water supply a fl fate of cold return water from the cold water outlet.

An advantage of this arrangement is that the cold water always circulates and therefore is kept cold in the cold water space and that the hot water always circulates and therefore is kept warm in the hot water space. This will effectively prevent bacterial growth. In addition, the convenience for the user increases in that cold and hot water is always available when the tapping point is used.

The flow of return water from the hot water outlet and the fl fate of return water from the cold water outlet are combined into a common fl fate of return water. Through this measure, circulation of both the hot and the cold water is achieved without the need for a network for cold return water. The common fl fate of return water is arranged to fl desert in a common return water pipe.

According to a preferred embodiment of the invention, the tapping point comprises a hot water inlet, a cold water inlet, a hot water space, a cold water outlet, a mixing core, a hot water outlet from the hot water space and a cold water outlet from the cold water space. The hot water outlet from the hot water space and the cold water outlet from the cold water space are connected by passage devices to a common return water outlet, which is adapted to connect to a common return water line.

According to another embodiment of the invention, the hot water outlet and the cold water outlet provide adjustment valves to control the fate and temperature of the return water. The adjustment valves are typically adjusted at one time so that the common fate of the return water obtains a desired temperature, which is preferably above 50 ° C. 10 15 20 25 30 523 144. . | According to a further embodiment of the invention, the mixing chamber is provided with a pressure-sensitive valve, which is arranged to be opened when the tapping point is not used to thereby drain and ventilate the mixing chamber and preferably all kinds of equipment connected to the mixing chamber, for example a shower hose.

Brief Description of the Figures Detailed embodiments of the invention will be described with reference to the drawings, in which Figure 1 is a front view of a known tapping point; Figure 2 schematically shows the tapping point according to Figure 1 in a closed position; Figure 3 schematically shows the tapping point according to Figure 1 in an open position; Figure 4 schematically shows a known water supply network; Figure 5 schematically shows the tapping point according to the present invention; Figure 6 shows, partly in a longitudinal cross-sectional view, the tapping point realized in a mixer according to a first embodiment of the invention; Figure 7 shows, partly in a longitudinal cross-sectional view, the tapping point realized in a mixer according to a second embodiment of the invention; Figure 8 shows, partly in a longitudinal cross-sectional view, the tapping point realized in a mixer according to a third embodiment of the invention; and Figure 9 schematically shows a water supply system in accordance with the present invention.

Related Art A known mixer and mixer housing will be briefly described with reference to Figures 1-3.

The mixer 10 comprises a mixer housing 12 with a hot water inlet 20, a cold water inlet 40 and a mixer outlet 34 which leads to a sink, bath or the like 80. The flow and temperature of the water leaving the mixer are controlled by the knobs 14 and 16, respectively. 1b and 1c show the principles behind the characteristic functions of the mixer according to U.S. Patent No. 6.02 1, 803. At one end of the mixer housing 12, the hot water inlet 12, which is connected to a hot water line 64, opens up to a hot water outlet 22 which can occupy a larger or smaller part of the interior of the mixer housing 12. A passageway 28 with an inlet valve 30 leads between the hot water outlet 22 and the mixing chamber 32. At the other opposite end of the mixing housing 12 opens on a f523 144 enu | In a corresponding manner, the cold water inlet, which is connected to a cold water line 70, up into a cold water space 42, which can occupy a larger or smaller part of the interior of the mixer housing 12. A passageway 48 with an inlet valve 50 leads between the cold water space 42 and the mixer core 32. An outlet valve 36 is provided between the mixer chamber 32 and the mixer outlet 34.

The inlet valves 30, 50 and the outlet valve 36 are, as indicated in Figures 2 and 3, mechanically connected to each other so that they can be adjusted when a user turns the knob 14 to open the mixer to the position shown in Figure 3, or to close the mixer to the position shown in Figure 2. The temperature of the water leaving the mixer chamber 32 is adjusted with the knob 16 which regulates the mutual opening conditions between the valves 30 and 50 to set the desired temperature of the mixed water. The knob 16 is further connected to a thermostat 46 which can iron the desired set temperature with the actual temperature via a line 44 and which, by feedback via a schematically illustrated transfer device 47, adjusts the mutual opening ratio.

This is a known mechanism.

According to said US patent, the mixer 12 also has a hot water outlet 24 from the hot water space 22. The hot water outlet 24 is arranged to be connected via an outlet valve 26 to a return line for hot water 66. As shown in Figures 2 and 3, the outlet valve 26 is arranged to be adjusted together with other valves. knob 14 is operated.

The outlet valve 26 is open in the closed mixer position (fi gur 2) and closed in the open mixer position (fi gur 3) so that the hot water space is continuously flushed with hot water when the mixer is not in use.

A drainage and ventilation outlet 54 extends from the mixer arm 32. This is opened and closed by the valve 56, which is operated with the other valves by turning the knob 14. More specifically, the valve 56 is arranged so that it is closed during the open mixer position (fi gur 3) and open during the closed mixer position (fi gur 2). If the mixer has two alternative outlets, such as a standard combined shower and bath mixer, both of these outlets can be drained via the outlet 54. To further reduce the risk of bacterial growth in the mixer chamber 32, this is designed with the smallest possible volume. 10 15 20 25 30 523 144 o | | | As proposed in U.S. Patent No. 6,021, 803, the cold water space 42 may also be provided with a water outlet, preferably through a valve similar to the hot water valve 26, and connected to a return line. Each tap must accordingly be provided with a hot water line, a cold water line, a return line for hot water and a return line for cold water.

The corresponding tap water system is schematically illustrated in Figure 4. to each individual tapping point 400.

The tapping points are illustrated here with the thermostat mixers described above. The cold return water is kept cooled by a cooling device 460, and the hot water is kept warm by a heating device 470.

Detailed Description of Embodiments A first embodiment of the present invention is described herein with reference to the schematic illustration shown in Figure 5. The mixer comprises a mixer housing 500, a hot water inlet 505, a cold water inlet 510 and a mixing water outlet 515 leading to a shower, for example. The hot water inlet 505 is connected to a hot water line 520 and leads to a hot water space 525. Similarly, the cold water inlet 510 is connected to the cold water line 530 and the cold water space 535. The hot water space 525 and the cold water space 535 are connected via a valve 540 and 545. 545 are operated either separately, or are mechanically connected to each other in a "single-lever arrangement". They may include thermostatic devices in arrangements similar to those described for the known mixer with reference to Figure 2. a hot water outlet 555 and the cold water space with a cold water outlet 560. The hot water outlet 55 and the cold water outlet 560 are connected via adjustment valves 565 and 570, respectively, in a common return water outlet 575 and connected to a common return water line 580. The purpose of adjustment The valves 565 and 570 are to set a mandatory fate of the hot and cold return water, and thereby also the temperature of the return water. The adjustment valves 565 and 5 70 are usually set during installation to give a desired fl fate and a desired temperature of the water in the return line, preferably above 50 ° C. The adjustment valves are not adjusted at 10 15 20 25 30 523 144 e »n ø | n 8 normal use. The temperature is chosen to reduce the growth of bacteria, as discussed above. Through these arrangements, the hot water parts of the tap will always be subject to a fl of hot water and the cold water parts of a av of cold water.

By combining these fates into a common return water outlet 575, only one return line, the common return line 580, is required.

The mixer chamber 550 is not subject to circulation when the mixer is not in use. Therefore, in order to reduce the risk of bacterial growth, the mixing chamber 550 is evacuated through a drainage and ventilation outlet 585 via a valve 590. The valve 590 is preferably a pressure sensitive valve, which is arranged to open when the pressure in the chamber goes below a predetermined value. When both inlet valves 540 and 545 have been operated to a closed position, i.e. when the mixer is no longer in use, the pressure in the mixer chamber 550 will drop and the valve 590 will be opened to drain the mixer chamber.

Pressure sensitive valves with suitable properties are commercially available. Care should also be taken to drain and ventilate parts of the tapping point that are connected to the mixer outlet 415, in Figure 5 exemplified by a hand-held shower. A shower hose 595 is made in a spiral shape, for example with metal reinforcements, and is extended by placing the hand shower 597 in a wall bracket 598, which has been positioned so that the shower hose spiral has a continuous downward curvature. This arrangement ensures that no water is trapped inside the shower hose 595 or the hand shower 597, and that all water will be drained through the drain and ventilation valve 585.

The invention has been illustrated here by describing a simplified mixer, which only shows the parts necessary for the basic functions. Drainage points can have a more complex construction with a large variety of valves, cold and hot water outlets and mixing chambers. In addition, the size and shape of such spaces can be varied in accordance with the design of the tapping point and / or the intended use. For example, water and cold water spaces can be included in the hot and cold water inlets. However, those skilled in the art will appreciate that constructions other than those illustrated above may also utilize the principles of the invention to provide circulation of hot and cold water, and to drain all spaces not suitable for circulation by means of pressure sensitive valves. An embodiment of the invention is shown in Figure 6. The hot water outlet 555 and the cold water outlet 560, from Figure 5, are realized by the passages 655 and 660, respectively, inside the mixer housing and are connected to a common return water outlet 675 (corresponding to 575).

As shown, the passages 65 and 660 are provided in the wall (602) of the mixer housing.

Adjustment valves 665 (565) and 670 (570) are provided before the passages connect to the common return water outlet 675, and are easily adjustable from the outside of the mixer housing. The hot and cold water inlet, 605 and 610, respectively, and the hot and cold water compartments, 625 and 635, and a mixing chamber 650, are also shown in the fi clock.

Figure 7 shows another embodiment of the present invention where the connection of the cold and hot water outlets is located outside the mixer housing. The mixer 702 has separate outlets for the hot return water 755 and the cold return water 760. The cold return water and the hot return water are then led into an external device, which comprises passages for hot and cold water, 704 and 706, respectively. They are preferably incorporated in a mixer wall bracket 708, which is shown in Figure 7, and are connected to a common return water outlet 775. The wall bracket may also include the adjustment valves 765 and 770. The Figure also shows hot and cold water inlets 705 and 710, respectively.

As discussed above, the cold parts of the mixer should be kept cold and hot parts kept warm.

Figure 8 illustrates an embodiment of the invention, intended to minimize heat transport, with two shafts 808 and 812. The shaft 808 is connected to the valve 840 which controls the flow of hot water from the hot water space 825 to the mixing chamber 850. The shaft 812 is connected to the valve 845, which controls fl the fate of cold water from the cold water space 835. The valves 840 and 845 are arranged for mutual and simultaneous operation through the shafts 808 and 812 and the handle 814. The handle 814 is preferably made of a material with low thermal conductivity. The knob 816 adjusts the proportion of hot water that is led into the mixer chamber 850. The figure shows the hot water outlet 855 and and the boiled cold water outlet 860 which allow circulation of hot and cold water, and the drain valve 890. By using a handle outside the actual mixer housing, instead of a continuous shaft , in order to connect the valve operations, the heat transport of the hot and cold parts of the mixer is reduced. By choosing materials for the mixer parts and for the mixer housing with low thermal conductivity, for example plastics, the heat transport can be further reduced. 10 15 20 25: 523 144. . »| .u 10 The water main network, by using the invention as exemplified by various embodiments, can be significantly simplified in comparison with the network according to Figure 4.

Figure 9 schematically shows an exemplary tap water network according to the invention.

The network includes a hot water line 940, a return water line 920, a cold water line 920, and is branched via pressure controlled regulators 910 and fed to the individual taps 900. Return water lines are arranged according to the well known principles of Tishelman coupling to provide proper circulation. In comparison with the network according to Figure 4, it should be noted that (a) no cold water return lines are needed and (b) no cooling device 460 is needed. The adjustments of all individual adjustment valves 570 and 565, the regulators 910 as well as others have been omitted in this description.

Devices necessary to control the fate and pressure of a network are considered to be well known to those skilled in the art.

By installing taps according to the invention at all taps, both hot and cold water are kept under constant circulation in the entire water supply network, and this regardless of whether the tap is open or closed. The risk of standing water being heated or cooled down to the risky temperature range is significantly reduced. It should be noted that all taps, not just shower faucets, for example, should be of the type offered by the invention to maintain the circulation of both hot and cold water in all parts of the water network.

The invention has been exemplified by embodiments which describe tapping points of the bath / shower luminaire type, but the invention must not be considered to be limited to such devices.

Other applications, such as dental care units, would just as well benefit from the invention.

It would be especially important to use the invention in equipment that is rarely used such as emergency showers and emergency eye showers.

From how the invention is described here, it is obvious that the invention can be varied in many ways. Such variations should not be seen as a departure from the idea or scope of the invention.

All such variations as are apparent to those skilled in the art are intended to be within the scope of the appended claims.

Claims (1)

A water circulation device intended to reduce bacterial growth in a water supply system, characterized in that the water circulation unit is arranged to be connected to a water tap point which comprises a cold water space (535; 635; 835) and a hot water space (525; 625; 825), the water circulation unit comprising: a hot water passage (555; 655; 704) which is arranged in liquid communication with the hot water space (525; 625; 825); a cold water passage (560; 660; 706) which is arranged in liquid communication with the cold water environment (535; 635; 835); and a connection device (575; 675; 775) for connection to a common return water line (580), the passages for cold and hot water (655; 704, 660; 706) being extended to the connection device (5 75; 675; 775), and thereby enables the circulation of water from the cold water space (5 35; 635; 835) and the hot water space (525; 625; 825) to the common return water line (580). The water circulation device according to claim 1, characterized in that the hot water passage (555; 655; 704) is provided with a first adjustment valve (565; 665; 765) and the cold water passage (560; 660; 706) is provided with a second adjustment valve (570; 670; 770) ), wherein the first and second adjustment valves are intended to control the fate of hot and cold water, respectively, from the hot water space and the cold water space, respectively, to the common return water line (580). The water circulation device according to claim 1, characterized in that the passages for water and cold water (5 55; 655; 704; 560; 660; 706) are arranged in a wall bracket intended for a water tapping point. The water circulation device according to any one of claims 1-3, characterized in that the water circulation unit is integrated in a tapping point, which tapping point is provided with a hot water inlet (505; 605; 705), a cold water inlet (510; 610; 710), a mixing chamber (550; 650). ; 850) which is connected to a hot water space (5 25; 625; 825) and a cold water space (535; 635; 835). The water circulation device according to claim 4, characterized in that the tapping point is a mixing fitting and the water circulation unit is arranged in the walls of the mixing housing. The water circulation device according to any one of claims 4-5, characterized in that the tapping point comprises a pressure-sensitive valve (590; 890) intended to evacuate the mixing chamber (550; 850). The water circulation device according to claim 6, characterized in that the pressure-sensitive valve is arranged to evacuate the mixing chamber when the pressure in the mixing chamber falls below a predetermined value. The water circulation device according to claim 6, characterized in that the tapping point further comprises a hot water inlet valve (540; 840), a cold water inlet valve (545; 845), the pressure-sensitive valve being arranged to open when both the hot water inlet valve and the cold water inlet valve is in a closed position. The water circulation device according to claim 4, further characterized in that the hot water inlet comprises the hot water space and the cold water inlet comprises the cold water space. The water circulation device according to any one of claims 4-9, characterized in that the tapping point comprises: a first shaft (808) which connects to the water water valve (840) intended to control the flow of hot water from the hot water space (825) to the mixing chamber (850); a second shaft (812) which connects to the cold water valve (845) intended to control the flow of cold water from the cold water space (835) to the mixing chamber (850), where the valves (840) and (845) are operated jointly by the first (808) and the the second shaft (812) and the handle (814), which handle is arranged outside the mixing housing, in order thereby to minimize the heat transport between hot and cold parts of the tapping point. ll. The water circulation device according to claim 10, wherein the handle (814) is formed of a material with low tennis conductivity. A tap water network comprising the water circulation device according to any one of the preceding claims, which network comprises a hot water mains (940), a number of hot water pipes branched from the hot water mains, a cold water mains (920) and a number of cold water pipes branched from the cold water mains. water, characterized in that at least one of the branched water and cold water pipes is provided with said water circulation device (900), and that the water network is provided with a back water main pipe (930) to which a number of return water pipes are connected, which return water pipes carry a mixture of hot and cold return water from the water circulation units.