GB2342746A - Water softener relenisher detector - Google Patents

Abstract

The detector senses the presence of replenisher 12 in a replenisher tank of an ion exchange water softener, the tank containing a water soluble replenisher, the detector comprising a sinker 14 and connected to an alarm, the arrangement being such that in use that in a first state the sinker rests on solid replenisher above the level of the solution contained in the tank with the alarm not activated and a second state the sinker rests on solid replenisher above the level of the solution contained in the tank and lower in the tank with the alarm activated.

Description

REPLENISHER DETECTORS FOR USE IN WATER SOFTENERS This invention relates to replenisher detectors for use in water softeners. Ion exchange based water softeners exchange ions such as Ca2, Mg2+ and HCO3-which cause temporary hardness for those such as Na+ and Cl-which do not. Periodically it is necessary to regenerate the resin. This is usually done by treating it with a strong solution of sodium chloride brine which displaces the hardness ions. In principle materials other than sodium chloride could be used but sodium chloride is generally preferred on cost and safety grounds.

Many consumers are first aware of exhaustion of the replenisher when hard water issues from the tap. Considerable quantities of water may be stored downstream of the water softener and fresh supplies of replenisher may not be available immediately. Thus it may be some time before softened water is again available.

According to the invention there is provided a sensor for sensing the presence of replenisher in a replenisher tank of an ion exchange water softener the sensor comprising a sinker connected to an alarm the arrangement being such that in use the sinker rests on solid replenisher the alarm being activated when the sinker descends lower than a predetermined point.

Embodiments of the invention will now be described by reference to the accompanying figures of which: Fig. 1 is a schematic view of a first embodiment Fig. 2 is a scrap view of a second embodiment; and Fig. 3 is a schematic view of a third embodiment.

Referring first to Figure 1 water softener unit 1 comprises ionexchange resin 2 received in container 3. Water to be softened enters through inlet 4. It percolates through the resin and softened water issue through outlets.

At intervals replenishers such as sodium chloride brine is passed through the ion exchange resin optionally by back flushing. The replenishing may be automatic or it may be user activated.

For example controller 6 could control the passage of brine. By way of non-limiting example controller 6 could be a timer regenerating the resin after a certain time has elapsed. Controller 6 could measure the volume of water passing through the resin. Those skilled will have little difficulty in devising other method such as monitoring the product water quality (as a function of hardness).

Controller 6 allows saturated replenisher solution to pass through the resin via conduit 8,9. In the embodiment of Fig. l replenisher solution is made by passing water via conduit 10 into container 11 where it mixes with replenisher 12 which may be particulate in form.

In the illustrated embodiment a second controller 13 such as a ball cock prevents container 11 from being filled too full. Other forms of second controller will suggest themselves to the skilled. Further examples are a timer which allow a valve to stay open for a predetermined time and volume meters.

Sinker 14 is providing in the container 11. Sinker 14 rest on the replenisher 12 without penetrating it to a great depth. Preferably the sinker is not buoyant in a solution of replenisher. The reason for this is that as shown in Fig. 1 when the replenisher is almost exhausted it may be covered by liquid. By ensuring that the sinker is not buoyant in this liquid an accurate indication of exhaustion or near exhaustion or a predetermined level can be achieved.

In the illustrated embodiment sinker 14 depends from line 15 for example of stainless steel or other material not corroded by replenisher solution. As replenisher solution is removed from the container and water runs in the replenisher dissolves and the sinker descends.

In the illustrated embodiment line 15 is connected to a control circuit having contacts 16,17. When contacts 16,17 are made (or broken) third controller 19 which may be remote activates an alarm.

The alarm can be a simple buzzer and/or light. However in some embodiments of the invention the sensor may be incorporated in a building management system. In this case and indeed in other cases a more sophisticated alarm could be used. For example the alarm could comprise a message on a computer screen. In some embodiments of the invention activation of the alarm generates an order for replenisher which is sent with or without user intervention to the replenisher supplier.

In some embodiments of the invention as for example in Fig. 2 a measure of the amount of replenisher remaining can be provided. One way of achieving this is to carry line 15 on a reel 20 which rotates as the sinker moves. Rotation of the reel can be measured for example using a potentiometer or an optical reader of the kind found inside computer mice.

In preferred embodiments of the invention the sinker and line is carried on lid 21 of the container. A reason for this is that when the lid is opened or removed the sinker will be lifted reducing the likelihood of it being buried by replenisher poured into the container.

While Figs. 1 and 2 may be helpful for the understanding of the invention modem water softening units are constructed somewhat differently as shown in Fig. 3. The operation of the invention is similar.

Container 100 contains replenisher. At the bottom of the container there is a slurry 101 of replenisher and saturated replenisher solution. Nearer the top when the container has been recharged there is solid replenisher 102. Sinker 103 rests on the surface of replenisher 102. The alarm may be activated prior to the top surface of the replenisher being covered in solution. Sinker 103 is carried by line 105 connected to lid 106. It will be apparent that it is not essential for the sinker to be carried on a line provided it is possible to detect its position.

The container 100 is provided with an overflow 107. Resin container 108 is received in container 100 and contains resin 109.

Water is passed into the resin container from inlet 110 and percolates through the resin to distributor 111. Softened water discharges through outlet 112. Pick-up 113 is connected via conduit 114 to the resin tank and is submerged in the replenisher solution. Responsive to control unit 115 water is passed into the container through the conduit 114 to dissolve further replenisher. Responsive to the control unit replenisher solution is also transferred to the resin container to replenish the resin.

It is not essential to carry the sinker on a flexible line. For example the sinker could be carried on a pivoted rod. A physical link is not essential and a magnetic or electromagnetic (eg radio or microwave) link could be used.

As described the invention has application both in domestic and industrial water softeners. Building management systems monitoring and/or controlling other building systems can incorporate the invention.

It will be apparent that the invention is useful both as a retrofit to existing water softeners and complete with new softeners.

Claims (9)

1. Claims 1. A sensor for sensing the presence of replenisher in a replenisher tank of an ion exchange water softener, the sensor comprising a sinker connected to an alarm the arrangement being such that in use the sinker rests on solid replenisher the alarm being activated when the sinker descends lower than a predetermined point.
2. 2. A sensor as claimed in claim 1 wherein the connection comprises a magnetic field or an electromagnetic radiation link.
3. 3. A sensor as claimed in claim 1 which depends from a lid of the tank.
4. 4. A sensor as claimed in any one of the preceding claims wherein the alarm is remote from the softener.
5. 5. A sensor as claimed in any one of the preceding claims wherein the alarm is visual.
6. 6. A sensor as claimed in any one of the preceding claims wherein the alarm is aural.
7. 7. A sensor for sensing the presence of replenisher in a replenisher tank of an ion exchange water softener substantially as described herein.
8. 8. A water softener system comprising a sensor as claimed in any one of the preceding claims.
9. 9. A building management system comprising a sensor as claimed in any one of the preceding claims.