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Field of the Invention

This invention concerns the hot and cold mixer valves with or without a thermostatic regulator for sanitary plumbing. State of the Art

In the bathroom finishings field, mixer valves in the form of cartridges, insertable in a tap body, designed to house two separate hot and cold water inputs and having devices for opening and closing the water inputs so as to adjust the flow and vary the mixer ratio of the two types of water depending on the temperature of the mixed water to be delivered through the output, are well known.

Said mixer valves can be with or without a thermostatic regulator. When they are without a thermostatic regulator, opening and closing, delivery adjustment, including the variation in the mixer ratio of the water may be carried out manually using the control lever. On the other hand, in valves equipped with thermostatic regulators, the variation in the mixer ratio of hot and cold water is autonomous due to the automatic control of the temperature of the mixed water delivered. Furthermore, also known is the application of a hydraulic pressure balancer on said valves in connection with hot and cold water inputs and suitable to compensate the pressure variations of the water coming from the water mains and in this way to prevent fluctuations in flow so as to maintain the ratio of the delivery of hot and cold water feeding the mixer valve, constant.

Mostly, according to the state of the technique, the pressure balancer is a separate unit that connects up to the mixer valve directly or by the interposition of hydraulic connections, increasing however the overall size and complexity of the group. Only in the case where mixer valves without a thermostatic regulator has a solution been proposed and achieved, where the balancer is positioned and housed in a part of the body of the valve itself, even though in a position transversal to the axis of said body.

As far as is known, the hot and cold water thermostatic mixer valves have never been provided with an incorporated balancer. Object and Summary of the Invention

The main object of this invention is to supply a hot and cold water mixer valve equipped with a pressure balancer not positioned transversely to the base of the valve but coaxially to it, that is concentrically to the body of the valve, independently the valve can be with or without a thermostatic unit. Another object of the invention is to propose and produce a hot and cold thermostatic mixer valve with a pressure balancer incorporated so as not to have complementary devices external to the valve itself and connected thereto.

Yet another object of the invention is to propose and produce a hot and cold thermostatic mixer valve with a pressure balancer incorporated, but without altering the usual functionality of the valve and without increasing its sizes and volumes, and where the valve can be equipped or not equipped with its own devices of opening and closing the water flow in output.

Still another object of the invention is to provide a hot and cold water valve mixer, with or without a thermostatic unit, complete with a coaxial pressure balancer, all in the form of a cartridge having overall sizes that allow universal

use and insertion, without the need for modifications, in the bodies of taps for bathroom, showers and the like, instead of and/or in substitution of the traditional thermostatic mixer valves without pressure balancers.

These objectives and implicit advantages deriving from them are achieved with a hot and cold water valve according to at least claim 1. Brief Description of the Invention

The invention will however be illustrated and become more evident in the continuation of this description made in reference to the enclosed indicative and not limiting drawings, in which: Fig. 1 is an enlarged section of a mixer valve complete with pressure balancer;

Fig. 2 is a partial view of the group in Fig. 1 ;

Fig. 3 is an analogous section as the one in Fig. 1 , but of a valve also equipped with a closing system; and Fig. 4 is a partial section of the pressure balancer associated with a mixer valve without a thermostatic unit. Detailed Description of the Invention

In Figs. 1 and 2 a thermostatic mixer valve is shown which is configured and equipped as a cartridge to be inserted as a whole in a body of a tap. It comprises a valve body 11 made up of a bottom cup element 12 and a top element 13 coupled according to an X axis, seal fitted and housing all the usual components present in a thermostatic mixer valve. Around the body 11 is envisaged an external jacket 14 defining, in combination with the beaker element

12 and the top element 13, a balancing chamber 15 accommodating a pressure balancer 16.

The body of the valve 11 delimits internally a mixing chamber 11' housing a mixing member 17 to control the temperature of the mixed water delivered. This mixer member 17 is associated in the known way with a thermostatic bulb 18 and is guided in the beaker element 12 and subject to axial movements in reply to the variations in temperature the thermostatic bulb is subjected to.

The movements of the mixer member 17 are opposed by two different contrasting springs 19, 20 respectively associated with the member itself and a hood 21 which rests on the summit of the thermostatic bulb 18.

The temperature of the mixed water can be set as required by turning a knob, not shown, fixed to a turning shaft 22 associated with the thermostatic bulb 18 by means of a slider 23 which engages with the spring 20 and, by means of this, with the hood 21 over the bulb.

The beaker shaped shell 12 has latterly, at different levels and however at the height of the mixer member 17, separate water feed openings 24, 25 of the hot and cold water respectively, and a bottom with an outlet passage 26 of the water towards a delivery point. The hot and cold water reach the feed openings 24, 25 trhough respective inlet passages 27, 28 formed in the external jacket 14 and in communication with conduits - not shown- that receive the water to be delivered according to arrows C and F , respectively. The pressure balancer 16 has the shape of a piston free to float axially in the chamber 15 formed by the external jacket 14 with the body of the valve. It has an intermediate section 31 connected on opposite parts with two annular portions, one lower 31 and one higher 32. sai annular portions 31, 32 have a smaller internal diameter with respect to the intermediate section and each are crossed by radial holes or slots 31', 32', respectively. The intermediate portion 30

of the balancer is guided on the external surface of the beaker element 12 and on the internal surface of the external jacket 14, in the area between the inlet passages 27, 28 of the hot and cold water. The annular portions 31 , 32 are guided only against the internal surface of the external jacket 14 on a level with said input inlets 27, 28.

The intermediate portion 30 subdivides the chamber 15 into two so called small variable volume chambers or spaces: a first lower chamber 33 for balancing the hot water; a second top small upper chamber 34 for balancing the cold water. The first small chamber 33 receives from one side, through the radial holes or slots 31', the hot water from the inlet passage 27 and on the other side it is in communication with the radial openings 24 feeding hot water into the mixer valve. In the same way, the second small chamber 34 receives from one side, through the radial holes or slots 32', the cold water from the inlet passage 28 and on the other side it communicates with the radial openings 25 feeding cold water into the mixer valve.

As said above, the mixer member 17 is on a level with the inlet openings 24, 25 and is movable axially in respect to the latter by means of the thermostatic bulb 18 . This bulb is in contact and is influenced by the temperature of the water passing through the mixing chamber 11' and, by dilating differently depending on the temperature of the water, causes the movements of the mixer member, which in this way varyingly opens or closes the hot and cold water feed openings 24, 25 and correspondingly the quantity of the two types of mixed water in order to maintain the temperature of the water delivered when mixed, constant.

When the pressure of the hot and cold water on entering the passages 27, 28 are the same, the floating piston of the balancer 16 remains in a balanced

position and the deliveries of the hot and cold inlet water are even. Consequently, the ratio of hot and cold water to be mixed do not change and there are no variations in the temperature of the mixed water delivered.

The position of the floating piston 16 changes only when the pressure of the hot and/or cold input water changes. In fact, if the pressure of the hot water that enters the balancing chamber 33 increases, the floating piston of the balancer 16 moves in the direction to close, more or less pronouncedly with its first annular portion 31 , the respective inlet passage of the hot water 27, whereas, from the opposite side, the second annular portion 32 of the piston opens more or less pronouncedly the cold water input passage 28. With an increase in the pressure of the cold water we have the opposite, the ratios of the quantities of the cold water are changed to maintain the temperature of the mixed water delivered, constant.

Worthy of note is the fact that the thermostatic mixer valve combined with a coaxial pressure balancer such as the one described beforehand may also be the type provided with a closing system and regulation of the water to be delivered in its base. Such a system can be made up of, as shown in Fig. 3, and in a way already known, by a fixed plate 35 and a movable one 36 resting and turning above the fixed one and connected to the body of the valve so that one turn of the latter is equivalent to one turn of the movable plate. Said plates have water outlet openings 35', 36' which consequent to the rotation of the movable plate 36 can be positioned at a distance one from the other to close the valve or in partial or total coincidence for the opening of the valve and delivery of the water coming from the bottom passage of the beaker element of the valve body.

Fig. 4 shows a mixer valve 40 without a thermostatic unit but with a coaxial pressure balancer 16 and applicable as one to the latter in a tap body 41. The mixer valve 40 has a valve body 42 with an X axis, which houses, in the usual way, a bottom fixed plate 43, a top plate 44 moving on the fixed one, a control system 45 of the movements of the movable plate and where the fixed plate 43 has two separate inlet passages 46 for the hot and cold water (even if the drawing shows only one) and a passage 47 for the outlet of the mixed water to the delivery point. This mixer valve 40 is positioned on base pedestal 49 and attached to it by means of a cover 50. The pedestal 49 has two lateral radial openings 51 , 52 at different levels, two longitudinal conduits 53 (the drawing only shows one) that place the said radial opening in communication respectively with the input passages of the fixed plate 43, and an outlet passage 54 in communication on one side with the outlet passage of said fixed plate and open on the opposite side towards the delivery point.

The pressure balancer 16 is the piston type, identical to the one described above in combination with the thermostatic valve. It is positioned coaxially around the base pedestal 49, between the latter and the external jacket 14, having the two input passages 27, 28 of the hot and cold water respectively, that come from a water mains network. The pressure balancer operates on a level with the radial openings 51 , 52 so as to close/open them independently to automatically adjust the quantity of the two types of water at input and consequently vary the ratio of mixed hot and cold water so as to maintain the temperature of the water to the delivery point, constant.