Patent Publication Number: US-2007095930-A1

Title: Installation, device and method for saving water

Description:
The present invention is intended to disclose an installation, a device and a method for saving water.  
      The present invention is intended to increase the saving of water and comfort, especially in installations for the consumption of running water (both in existing and in new buildings), which are provided with hot and cold water circuits and with common water dispensing points for both circuits.  
      This type of installation is found, for example, in modern residential properties which currently are provided, in their entirety, with hot water for sanitary purposes.  
      In these installations, when the user requests hot water from a water dispensing point, usually the tap, a certain period of time must elapse before the temperature of the water emerging via this water dispensing point reaches the required temperature. This is a disadvantage, because contact with cold water is always an irritation, especially in the case of babies and young children. Accordingly, habitually the water is allowed to flow from the water dispensing point until the temperature required by the user has been reached. This involves an unnecessary waste of water, at a time at which the saving of water is a matter of major concern to the authorities.  
      To resolve this problem, the prior art has offered various solutions, which exhibit certain disadvantages.  
      The documents U.S. Pat. No. 6,098,213 and U.S. Pat. No. 4,924,536 disclose an energy-saving device and a running water installation for the same purpose, in which the hot water which has not reached the required temperature is diverted to a specific ancillary filling circuit for the tank of a water closet.  
      These installations have the disadvantage that they require the arrangement of an installation of specific pipes from each water dispensing point to the tank of the closet. In addition, the devices disclosed in the said documents are only applicable with difficulty to existing taps, since they require a specific location for their installation. In addition, no harnessing of the energy takes place from the water which is diverted to the tank.  
      The document CA 2252350 discloses a water consumption installation in which the hot water which does not reach the required temperature is diverted to an intermediate tank in the cold water circuit, which also requires the installation of long pipes from each water dispensing point to the intermediate tank, which renders it difficult to apply to existing installations. On the other hand, the obtaining of adequate pressure in the cold water circuit requires the placement of an intermediate tank in an excessively high position, and no harnessing of energy takes place from the hot water send to the tank.  
      The present invention has the following objects: 
          To provide hot water without the user coming in contact with the cold water     To achieve a substantial and simultaneous saving of water and energy,     To contribute to current environmental policy without causing the disadvantages referred to heretofore.        

      All this to be achieved with means which assume a minimum investment in comparison with the savings and convenience obtained, and of easy application to existing installations.  
      In order to achieve these objects, the present invention consists of a method for the saving of water in installations for the consumption of running water, of the type comprising cold water and hot water circuits, and at least one common water dispensing point, which comprises a transfer of water from the hot water circuit to the cold water circuit, via the water dispensing point, prior to the consumption of hot water, during a period of time such that, at the end of the transfer, the water from the hot water circuit at the water dispensing point has the required temperature. In this way it is possible to increase the convenience of the installation. The water transferred to the cold water circuit can be exploited subsequently, which in this way achieves an appreciable saving of energy. The transfer of the water via the water dispensing point renders unnecessary the provision of pipes specifically for the exploitation of this water.  
      The subsequent exploitation of the water transferred to the cold water circuit can comprise intermediate storage and subsequent transfer of the stored water to a water dispensing point of the installation by way of the installation itself.  
      Preferably, the method includes the transfer of the water from the cold water circuit to a point in the water installation upstream of a hot water generator located in the hot water circuit of the installation.  
      This configuration allows to advantage for the intermediate storage to be done away with. In addition to this, by means of this preferred embodiment it is possible to achieve better harnessing of the energy from the hot water by means of the generator of the hot water which has not reached the required temperature.  
      Likewise, the present invention consists of an installation for the consumption of running water, of the type comprising hot and cold water circuits and at least one common water dispensing point for both circuits, characterised: 
          in that the cold water circuit operates at lower pressure than the hot water circuit,     by at least one device located at a common water dispensing point for the hot and cold water circuits, which comprises a control element which can be actuated by the user, allowing water to pass from the hot water circuit to the cold water circuit via the water dispensing point, and, preferably, a device which determines, by way of temperature-sensitive means, the time during which both circuits are in communication, and     by means located in the cold water circuit for the discharge of the volume of water deriving from the hot water circuit.        

      Preferred embodiments of the invention are characterised by the provision means of reusing the water in the intermediate tank.  
      In preferred embodiments, means are provided which allow for the reuse of the water from the intermediate tank by way of the installation, when consumption takes place in the installation, causing the stored water to return to the water circuits for consumption at the water dispensing points.  
      Preferably, the means of discharge comprise devices for shutting off the intake of water into the cold water circuit and opening the discharge mechanism, and means sensitive to the pressure of the cold water circuit.  
      Preferably, the said means of discharge comprise time-sensitive means, which regulate the opening and closing time of the said devices for opening the discharge mechanism and closing the cold water circuit.  
      More preferably, the means of discharge of the volume of water deriving from the hot water circuit of the installation comprise means for the transfer of water from the cold water circuit at a point of the installation upstream of the hot water generator of the installation, without intermediate storage of the water.  
      Thanks to this configuration, it is possible to dispense with the said tank, which achieves a saving of space, as well as a reduction of the costs of providing the installation.  
      In a preferred embodiment, the said means for transferring water from the cold water circuit to the hot water circuit comprise a pump and a retention valve.  
      The device for saving water located at the water dispensing points can be configured as a manual valve, of known type, which connects the cold water circuit to the hot water circuit, which lacks of temperature-sensitive means, the user being responsible for determining the connection time for the two circuits and if the temperature of the water at the water dispensing point has reached the required temperature.  
      In this way, it is possible to achieve an additional saving with regard to the costs of the investment in the installation.  
      In a number of preferred embodiments, the time-sensitive means comprise a timer, of which the actuation time is determined during installation.  
      Preferred embodiments are also characterised by being provided with means which render the said means of reutilisation of the water inactive when the water discharge mechanism is in operation.  
      Likewise, preferred embodiments of the said device located at the water dispensing points are characterised by being capable of being connected to the taps known from the market.  
      The communication time between the hot and cold water circuit can be determined by temperature-sensitive means, or can be fixed, being adjusted during the installation of the device.  
      Likewise, in order to achieve the object of disclosing means of economising which can be easily applied to existing installations, the present invention also comprises a device for saving energy in the realisation of an installation or of the method according to the present invention, of a type which can be connected to taps for common water dispensing points for hot and cold water circuits, which comprises a control element which can be actuated by the user and temperature-sensitive means by means of which the operational position of the device can be determined, characterised in that it comprises: 
          a body which can be connected to the outlet from the tap;     a through-opening for the passage of the water deriving from the tap to consumption;     a blocking element for the said through-opening;     means for causing the movement of the blocking element, with the subsequent unblocking of the through-opening, and     means for controlling the said movement of the said blocking device, as a function of the said temperature-sensitive means.        

      Said temperature-sensitive means may comprise a heat-sensitive spring.  
      Said means for causing the movement of the blocking element may comprise a spring.  
      Said means for controlling the said blocking device can comprise a mechanism with a releasable detent means capable of exercising resistance to the force exercised by the spring of the said means for causing the movement of the blocking element.  
      Said user control element can be such as to allow the user to place the device in a position in which the passage of the water is blocked and the said detent means blocks the movement of the blocking mechanism.  
      The device can incorporate a filter at its water outlet.  
      The detent means can comprise a piece of variable section, the movement of which is governed by the heat-sensitive detent means, the movement of the piece of variable section causing, in its turn, the movement of a piece provided with a runner, into which said variable section is introduced, said piece providing a detent means for said blocking element, as well as by resilient recovery means which ensure the contact of the variable section with one of the ends of the runner.  
      The control element can consist of an actuatable button which presses the detent means of the means for causing the movement of the blocking element, allowing for the automatic resetting of the detent means into its initial position blocking said resilient force.  
      In this way, when the customer requires hot water, he first actuates the control element for the device and turns the tap on. Accordingly, the economising device blocks the outflow of water from the tap until the water has reached the required temperature, at which moment the dilation of the heat-sensitive detent means brings about the movement of the plug, which in turn brings about the movement of the piece with the runner, which in turn unblocks the blocking mechanism, allowing for the resilient means to open the through-opening of the device, this allowing the passage of the hot water for consumption. During the period during which the device remains closed, the water passes from the hot water circuit to the cold water circuit, in order to save it. 
    
    
      For better understanding, drawings are appended hereto by way of explanation, but not limitation, of a preferred embodiment of the present invention.  
       FIG. 1  is a diagrammatic representation of an installation for the consumption of running water in accordance with the present invention.  
       FIG. 2  shows a diagrammatic representation of an installation for running water.  
       FIG. 3  is a side view of a water-saving device according to the present invention, connected to a tap for hot and cold water.  
       FIG. 4  is a plan view of the device from  FIG. 3 , in which the internal elements of the water-saving device can be seen, and its connection to the water circuit and to the tap.  
       FIG. 5  shows a perspective view of a domestic tap, provided with a device according to the present invention.  
       FIG. 6  is a view from above of the internal elements of the device with the mechanism blocking the outlet of water from the tap.  
       FIG. 7  corresponds to  FIG. 6 , in a position in which the heat-sensitive detent means has brought about the opening of the device, unblocking the outlet of water from the tap. 
    
    
      The present invention is based on an installation for the consumption of running water of known type, which in the particular case of the example shown in  FIG. 1  corresponds to a running water installation of a residential property, of known type, consisting of a first common section  1  which, as can be seen in  FIG. 1 , presents in this case a shutoff key  19  and a pressure regulator  20  for the system, a hot water circuit  2  with a boiler system  22 , a cold water circuit  3 , and at least one water dispensing point  4 , in this case a tap for hot and cold water.  
      As a characteristic of the present invention, the tap  4  is provided with a device  5  which can be actuated by the user. In the example shown in  FIG. 2 , the actuation of the device is effected by a button  6  provided with a spring.  
      The installation according to this invention is also characterised by the cold water circuit  3  operating at a pressure lower than that of the hot water circuit  2 . In the case of the particular embodiment shown in  FIG. 1 , this is achieved by means of a pressure regulator  7  located at the start of the cold water circuit  3 . Likewise characteristically, the cold water circuit  3  possesses means for discharging the volume of water which may come via the device  5 , to which reference is made in  FIG. 1  by the number  8 . Said device must be provided with means for setting it in motion when the device  5  allows for a volume deriving from the hot water circuit  2  to enter into the cold water circuit  3 . In the example shown, this is effected by means of two electric valves  9 ,  9 ′, which simultaneously open the device  8  and close the entry of cold water to the circuit  3 , said valves  9 ,  9 ′, being controlled by a pressure-sensitive mechanism  10 , such as a pressure switch.  
      In a preferred manner, the present invention makes provision for the discharge device to include an intermediate tank  11 . In the example shown, the intermediate tank  11  likewise possesses a level indicator  15  to indicate an excess or deficit of the filling of the device  11 . A typical value of the capacity of said tank  11  for use in residential properties is approximately 50 litres.  
      Also in a preferred manner, the present invention makes provision for the water stored in the intermediate tank  11  to be recovered via the water consumption installation itself by means of a device, to which reference is made in  FIG. 1  by the number  12 , which connects the intermediate tank to the water installation. In the example shown, the device  12  comprises a pump  13  for pumping the water from the tank  11  to the circuit  3 , which is controlled by a pressure switch  14 . The reutilisation device  12  is likewise provided with a non-return valve  16 , which prevents the tank from being filled via the water recovery device. In the example shown, and in order to provide perfect co-ordination between the discharge devices  8  and the reutilisation devices  12 , provision has been made for a timer  17  and a relay  18  in the installation.  
      The method according to the invention is characterised in that it comprises the steps of transference of water deriving from the hot water circuit  2  to the cold water circuit  3  prior to the consumption of the hot water, and the subsequent recovery of the volume of water transferred to the cold water circuit  3 . Said recovery comprises preferably a storage arrangement and a subsequent transfer to a water dispensing point of the installation via the water circuits.  
      As is explained in detail hereinafter, the installation from the example shown in  FIG. 1  implements the step of transfer of the water deriving from the hot water circuit  2  to the cold water circuit  3  by the use of the economiser device  5  located at the water dispensing points (as well as by means of the difference in pressures between circuits  2  and  3 ), the storage being effected by the actuation of the discharge device  8  and achieving said transfer of the stored water by means of the reutilisation device  12 .  
      When the user requires hot water, he actuates the device  5 , which in the case of the example shown is effected by pressing the button  6 . The device  5  allows for passage from the hot water circuit  2  to the cold water circuit  3  during the time set by the temperature-sensitive mechanisms of the device  5 .  
      The functioning of the discharge device  8  in the example is as follows: When the hot water circuit  2  communicates with the cold water circuit  3 , an increase in the pressure of the cold water circuit  3  is produced. This increase in pressure actuates the pressure switch  10 , which in turn, via the timer  17 , actuates the discharge device  8 , opening the electric valve  9  of the inlet to the intermediate tank  11  and closing the electric valve  9 ′ for admitting water to the cold water circuit  3 . In addition, by way of the relay  18  of the discharge device  8 , the means for reutilisation  12  are disconnected, shutting off the signal from the pressure switch  14 . This circuit situation is maintained for a period determined by the timer  17 . The time determined by the timer can be fixed, for example, determined during the installation of the circuits  2  and  3 , in such a way that the time determined will be greater than the time taken by the water deriving from the hot water circuit  2  to reach the required temperature at the most distant water dispensing point. As a variant, it is possible to make the duration of this situation dependent on the temperature-sensitive mechanisms, or on the pressure at a predetermined point of the water circuit, or including the position of the button  6 .  
      The functioning of the reutilisation device  12  is as follows: When cold water is requested from the circuit  3  via the water dispensing point  4 , turning on the tap  4  brings about a drop in the pressure of the circuit  3 , which actuates the pressure switch  14 . The signal deriving from the pressure switch  14  sets the pump  13  in action, which drives water from the tank  11  into the cold water circuit  3 . When the tap  4  is turned off, the pump  13  brings about an increase in the pressure in the circuit  3 , which in turn produces a signal deriving from the pressure switch  14  to the pump  13 . The pressure level of the pressure switch  14  must be lower than that of the pressure switch  10 . In another preferred embodiment, the functioning of the pump  13  can also be governed by a signal deriving from the level  15  of the intermediate tank  11 , in such a way that the functioning of the pump  13  is prevented if the tank  11  does not have a certain level of water as required.  
      The preferred embodiment of the installation from  FIG. 2  is a running water installation, of the type used in residential properties. The installation is comprised, as the example shown in  FIG. 1 , of a first common section  1 , which exhibits a shutoff key  19  and a pressure regulator  20  for the installation, a hot water circuit  2  with a boiler system  22 , a cold water circuit  3 , and at least one water dispensing point  4 , in this case a tap for hot and cold water. The tap  4  is provided with a device  5  which can be actuated by the user, and which brings into communication the hot water circuit  2  and the cold water circuit  3 , as has been explained in the description to  FIG. 1 . The hot water circuit  2  operates at greater pressure than the cold water circuit  3 . In the example, this is effected by means of the pressure regulator  7  located at the beginning of the cold water circuit  3 .  
      The example shown also comprises, as shown in  FIG. 1 , the valve  9 ′ and the pressure switch  10 , located in the cold water circuit.  
      In a manner characteristic of this embodiment, the discharge means  8  connect the cold water circuit  3  to a point of the installation located upstream of the hot water generator or boiler  22 , which in the example is effected by means of a pump  13 , which can be of similar characteristics to the pump used in  FIG. 1  to draw water from the intermediate tank, and a non-return valve  23 .  
      The pressure switch  10  governs the functioning of the valve  9  and of the pump  13  by way of the relay  24 .  
      When the device  5  is actuated by means of the control button  6 , the hot water circuit  2  and the cold water circuit  3  are connected, which causes an increase in the pressure of the cold water circuit  3 . To increase the pressure, the pressure switch  10  connects the relay  24 , which closes the valve  9 ′ and sets the pump  13  into operation. When the temperature of the water at the water dispensing point  4  is as required, the hot and cold water circuits remain disconnected. The action of the pump  13  causes the pressure to be reduced below the alarm level for the pressure switch  10 , which stops the pump  13  and opens the valve  9 ′.  
      Thanks to this connection of the means of discharge  8  at a point located upstream of the boiler  22 , it is possible to do without the intermediate storage device shown in  FIG. 1 . This simplifies the installation, reducing costs and saving space.  
      Another embodiment provided for, not shown in the Fig., consists of replacing the device  5  by a manual actuating valve, of known type, which connects the hot water circuit  2  and the cold water circuit  3 , doing without temperature-sensitive means, it being the user who must determine when the temperature of the installation has reached the required value.  
      In this way, the investment costs are also reduced. While it is true that this improvement is accompanied by a certain reduction in terms of convenience for the user, it cannot be a disadvantage in certain types of installations, such as installations with low consumption index, such as second homes.  
       FIG. 3  shows a particular embodiment of the device  5 . In this particular embodiment, the device  5  can be connected to any tap  4  from among those on the market, by means of standardised connectors or connections  29 ,  29 ′. The joint is covered by a decorative cover  21 , from which protrudes only the control element  6 , which in this example consists of a button actuated by a spring. If the button  6  is actuated, the device  5  brings the hot and cold water circuits into operation for a period of time determined by the temperature-sensitive means provided, such as a heat-sensitive spring. When the water deriving from the hot water circuit  2  reaches the required temperature, the device stops the communication between the hot water circuit  2  and the cold water circuit  3 , and allows for the water to depart via the water dispensing point  4 . In the particular case of the embodiment shown, the button  6  again returns to its initial position when the temperature of the hot water reaches the required temperature, indicating to the user that there is hot water available. A typical value of the temperature required for the water consumption installation in residential properties is 38° C.  
      In  FIG. 5  to  7  a tap  31  is shown, to which a water-saving device  5  has been connected, according to the present invention, at the water outlet of the tap. The device can be connected to taps which are currently found in installations, simply by replacing the filter which taps have at the outlet by the device  5 , so facilitating the conversion of a domestic running water installation into a water-saving installation according to the invention.  
      The composition and functioning of the device  5  are described hereinafter by reference to  FIGS. 6 and 7 . In these figures a section through the device  5  can be seen, the object of the present invention, in which its different elements can be identified. The said device  5  comprises a body which, for example, can be screwed to the tap  31 , using the thread provided for the outlet filter from the tap and comprises a through-opening  40  for the passage of water, which can be closed off by a blocking mechanism, comprising a blocking element  39  and a spring  36  which exerts a force which causes the blocking element  39  to block the through-opening  40 . The movement of the blocking element  39  is stopped by a detent means element, which comprises a detent means piece  42 , which is provided with a runner into which is introduced an element of variable section or wedge  43 , the movement of which is governed by the dilation of the heat-sensitive spring  37 . A recover spring  41  exerts a resilient action on the detent means piece  42 , which ensures that at any moment the wedge  43  is in contact with the upper end of the opening or runner of the piece  42  In this way it can be ensured that the detent means piece  42  responds with vertical ascending and descending movements to the horizontal movements of the piece  43 . The device  5  can also be provided, as in the example shown, with a filter  34  at the water outlet.  
      The functioning of the device is as follows. Starting from the state with the through-opening  40  blocked, which is shown in  FIG. 6 , the user simultaneously opens the inlets to the tap  31  deriving from the hot and cold water circuits. This can be done in a simple manner by means of the control arrangement of currently known taps. In this position, the force of the spring  36 , which tends to open the opening  40  is cancelled by the detent means  42 , which is pushed downwards by the spring  41 .  
      When the temperature of the water reaches a predetermined level, as shown in  FIG. 7 , the heat-sensitive spring  37  dilates and causes the movement of the wedge  43 , which in turn causes the piece  42  to rise, with which the effect of the detent means disappears and the spring  36  displaces the blocking element  39 , unblocking the opening  40  and allowing a jet of hot water  35  to emerge from the tap via the filter  34  of the device  5 . For a better response by the mechanism to changes in temperature, the heat-sensitive spring can incorporate an extension of the probe  38 , such as a strip or wire of heat-conductive material, which is introduced into the interior of the tap  31 .  
      Starting from the position in  FIG. 7 , and once the user has turned off the tap  31 , the user can, if he wishes, return the device  5  to the position of water-saving from  FIG. 6  by pressing the control element or button  33 , whereby the device  5  is again available to be used.  
      There are numerous variants of the example shown in  FIG. 1 , which fall within the scope of the present invention. Thus, for example, the means of discharge  8  can include a delivery pump from the tank  11 , the functioning of which is governed by the pressure switch  10 , in a manner similar to the way the valve  9  is controlled in the example shown. In this way, greater speed of transfer of water can be achieved from the hot water circuit  2  to the cold water circuit  3 . It is also possible to use for this purpose the pump  13  for emptying the tank  11 . In this case, a system of electric valves, controlled by means of the pressure switches  10  and  14 , is installed at the intake and outlet of the pump  13 , in such a way that the pump  13  fills the intermediate tank  11 , or empties it, depending on whether hot or cold water are required respectively at the water dispensing point  4 . In another variant, the installation may exhibit pressure switches  10  and  14  in the same device, while likewise the valves  9  and  9 ′ can be replaced by a three-way valve performing the same function. The time determined in the example shown by the timer  17  can, alternatively, be determined by the functioning of the device  5 , or by the pressure or the temperature of a point in the cold water circuit  3 , in such a way that the time during which the discharge device  8  is activated, and the re-use device  12  is deactivated, coincides with the communication time between the hot water circuit  2  and the cold water circuit  3 . Other embodiments may do without the relay  18 , and include the timer  17 . Another possible variation consists of connecting the re-use device  12  between the intermediate tank  11  and the intake to the hot water circuit  2 . It is also possible, for example, to do without the re-use device  12  or also to include the intermediate tank  11 . In this case, the discharge device  8  can be reduced to one all-or-nothing pressure-controlled opening valve, in such a way that it opens when the pressure in the cold water circuit  3  falls to the pressure level of the hot water circuit  4 , causing the water to be re-used in the other circuit or application. On the other hand, the invention is not limited to the individual installation shown in the figure and the installation can be applied, for example, to installations in residential properties which have centralised sanitary hot water, or includes installations in buildings with centralised circuits for hot and cold water.  
      There are numerous variants of the example from  FIG. 2  which fall within the scope of the present invention. For example, in one alternative embodiment it is possible to dispense with the valve  9 ′, replacing it by a non-return valve, if this functioning cannot be realised by means of the regulator  7 . In this way it is possible to connect directly the signal from the pressure switch  10  to the pump  13 . The person skilled in the art will also perceive multiple combinations between the embodiments disclosed here.  
      It is likewise possible for the device  5 , located at the water dispensing point, to be provided with other control elements, of known type, in order to regulate the temperature required for the hot water. It is also possible for it to have configurations different to those shown, and in particular for it to be integrated and form an assembly with a tap  31 ,  4 . It is also possible to generate other known types of visual or audible signals to advise the user when the temperature at the water dispensing point  4  reaches the required temperature.  
      It is also possible for the control element  36  to be provided with a slot or flange (not shown) in order to take it out of service, in which case the device  5  is forced manually to unblock the opening  40  in order to return the device  22  to the position in  FIG. 7 . It is also possible to incorporate a mechanism in order to be able to determine the temperature of the water in an adjustable manner, causing a dilation in the heat-sensitive spring  37  such that the device opens. This can be achieved, for example, by means of a rotating piece inside the device, which causes torsion in the heat-sensitive spring  37 , or by other known means. It is also possible to include electronic equivalents to the elements shown, such as replacing the heat-sensitive spring by a thermostat, and actuating the detent means system by means of the thermostat signal, such as by way of an electric valve or similar.