GB2613774A - A thermostatic shower valve - Google Patents

Abstract

A thermostatic shower valve 2 comprising a thermostat 4 and a valve block: (i) the thermostat comprises several separate component parts 8 which are releasably assembled together to form the thermostat but does not comprise a housing, without housing, for creating a cartridge. (ii) the thermostat is in a thermostat-receiving bore 10 in the valve block 6 and the bore is defined by a bore wall (12) in the valve block which forms the housing of the thermostat. (iii) the valve block s machined metal, such as aluminium or brass valve block and includes machined inlet and outlet bores for water flow in and out of the block. The thermotstat can include: a return spring; baffle, piston; thermostatic element, such as a wax element; overtravel spring plug; overtravel spring housing; a screw plug; a spindle for control and a main head member.

Description

A THERMOSTATIC SHOWER VALVE

This invention relates to a thermostatic shower valve.

Thermostatic shower valves are well known. They comprise a thermostat and a valve block. The thermostat comprises assembled component parts mounted in a housing. The thermostat is made of a plastics material and it is in the form of a cartridge which is designed to be thrown away if problems occur, for example if the thermostat becomes clogged with limescale. The thermostat is thus designed as a minimum-cost, easily-replaced item. Whilst such an item may initially appear attractive from a commercial aspect, there are disadvantages. More especially, because the thermostat is not designed for repair, it has to be discarded and replaced by a new one even if a fault occurs which is extremely minor and which would be easy to correct. Furthermore, the thermostat is not able to accessed for routine maintenance. The result is that sometimes the thermostat is discarded when it is not really necessary. Cost is incurred in providing a replacement thermostat. Also, the discarding of the thermostat is bad for the environment in that the thermostat has to be disposed of If the thermostat is buried, then unnecessary landfill problems may occur. This is especially so since the thermostat is made of a plastics material and the plastics material is not bio-degradable.

It is an aim of the present invention to avoid or reduce the above mentioned problems whilst at the same time providing a thermostatic shower valve which is able to operate more efficiently than the known thermostatic shower valves Accordingly, in one non-limiting embodiment of the present invention there is provided a thermostatic shower valve comprising a thermostat and a valve block, and wherein: (i) the thermostat comprises a plurality of separate component parts which are releasably assembled together to form the thermostat; (ii) the thermostat formed by the assembled component parts does not have a thermostat housing; (n) the thermostat is in a thermostat-receiving bore in the valve block; (iv) the thermostat-receiving bore is defined by a bore wall in the valve block; (v) the bore wall forms a housing for the thermostat; (vi) the valve block is a machined metal valve block; (vii) the valve block comprises inlet and outlet bores for enabling water to flow in and out of the valve block; and (viii) the inlet and outlet bores are machined inlet and outlet bores. Because the thermostat in the thermostatic shower valve comprises a plurality of separate component parts which are releasably assembled together to form the thermostat, the thermostatic shower valve is able to be such that the thermostat can be maintained and repaired. This avoids the problem of having to discard the thermostat and the resulting adverse affects on the environment. In addition, because the assembled component parts of the thermostat do not have a thermostat housing, the thermostatic shower valve is able to operate more efficiently than the known thermostatic shower valves. More specifically, the absence of a housing for the thermostat enables water passing through the thermostatic shower valve to have better access to a thermostatic element in the thermostat. This enables the thermostat to have a faster response time to hot and cold requirements of a user. It also enables the temperature of water passing through the thermostatic shower valve not to fluctuate as much as would be the case with a known cartridge thermostat with its own housing. This reduced fluctuation enables water passing through the thermostatic shower valve to have greater accuracy for the temperature selected and with less variation of this selected temperature, Still further, flow rates through the thermostatic shower valve may be improved in comparison with known thermostatic shower valves with their cartridge thermostat because there is no thermostat housing for potentially slowing down the passage of water through the thermostatic shower valve. Still further, because the valve block is a machined metal valve block, the valve block is less likely to promote unwanted temperature fluctuations than is the case with the known thermostatic shower valves and their valve blocks made of an extruded plastics material.

The thermostatic shower valve of the present invention is typically one in which the valve block has straight sides.

The thermostatic shower valve may be one in which the component parts of the thermostat comprise a return spring, a baffle, a piston, a thermostatic element, an over-travel spring housing, an over-travel spring plug, a screw plug, a spindle for on/off control of the thermostatic shower valve, and a main head member.

The spindle is preferably a non-rising spindle. The spindle may however be a rising spindle if desired.

The thermostatic element may comprise wax for providing travel of the thermostatic element and the piston.

Preferably, the valve block is made of brass or aluminium. Other metals may be employed.

An embodiment of the invention will now be described solely by way of example and with reference to the accompanying drawings in which: Figure 1 is an exploded part sectional view through a thermostatic shower valve of the present invention and comprising a thermostat and a valve block; Figure 2 shows the thermostatic shower valve as shown in Figure 1 in enlarged size and with the exploded parts connected together; Figure 3 is a view like Figure 2 but in the same size scale as Figure 1; Figure 4 shows the valve block as shown in Figure 3 and without the thermostat; Figure 5 is a perspective view of the thermostatic shower valve and Figure 6 is a view like Figure 5 but without the thermostat.

Referring to the drawings, there is shown a thermostatic shower valve 2 comprising a thermostat 4 and a valve block 6.

The thermostat 4 comprises a plurality of separate component parts 8 which are releasably assembled together to form the thermostat 4. The thermostat 4 formed by the assembled component parts 8 does not have a thermostat housing.

The thermostat 4 is in a thermostat-receiving bore 10 in the valve block 6. The thermostat-receiving bore 10 is defined by a bore wall 12 in the valve block 6. The bore wall 12 forms a housing for the thermostat 4.

The valve block 6 is a machined metal valve block. The valve block 6 comprises inlet and outlet bores 14, 16 for enabling water to flow in and out of the valve block 6. The inlet and outlet bores 14, 16 are machined inlet and outlet bores 14, 16.

The valve block 6 has straight sides 18 as shown.

The component parts 8 of the thermostat 4 comprise a return spring 20, a baffle 22, a piston 24, a thermostatic element 26, an overtravel spring housing 28, an overtravel spring plug 30, an overtravel spring 32, a screw plug 34, a non-rising spindle 36 and a main head member 38. The thermostatic element 26 comprises a wax capsule (not shown) for providing travel of the thermostatic element 26 and the piston 24.

The valve block 6 is made of brass.

The valve block 6 may be produced by the process described in UK Patent No. 2547618. As described in detail in UK Patent No. 2547618, the process comprises: (I) obtaining a standard non-straight extruded solid rectilinear bar of a material from which the valve is to be made; (ii) ensuring that the standard non-straight extruded solid rectilinear bar is of a standard offered cross-sectional size which is larger than and nearest to the required cross-sectional dimensions of the valve; (iii) straightening the standard non-straight extruded solid rectilinear bar, whereby the standard non-straight extruded solid rectilinear bar is straightened to become an extruded straight solid rectilinear bar of the required cross-sectional shape for the valve; (iv) machining the extruded straight solid rectilinear bar by finish skim machining only; and (v) drilling bores for receiving the thermostat, hot water, cold water, and thermostatically mixed hot water and cold water.

The thermostatic shower valve 2 is able to serve two shower outlets, one via a shower outlet port 14 and the other via a shower outlet port 16. One shower outlet may be for a fixed showerhead, whilst the other shower outlet may be for a hand-held shower.

The valve block 6 comprises bores 40, 42. The bore 40 leads to a water inlet 44. The bore 42 leads to a water inlet 46. One water inlet 44 is for receiving cold water and the other water inlet 46 is for receiving hot water. Either inlet 44, 46 can be for cold water, with the other inlet 44, 46 being for hot water.

Screw threads 48, 50 are able to receiving blanking caps (not shown).

The bore 40 leads via a bore 52 to the bore 54. The bore 52 leads via a bore 56 to the bore 54. In the bore 54, the hot and cold water from the bores 40, 42 are mixed together until a required temperature is reached, as determined by the control thermostat 4 which is in the thermostat-receiving bore 10.

The mixed water at the required temperature passes along a bore 58 to a bore 60. The bore 60 terminates in a non-return check valve 62. When the non-return check valve 62 is opened, water from the bore 60 flows via a bore 64 into a bore 66 and out through the shower port 68. The bore 58 is blocked by a plug 70.

Similarly, water at the required temperature from the bore 54 is able to pass along the bore 72 into bore 74. The upper end of bore 74 receives another non-return check valve 76. When the non-return check valve 76 is opened, then water is able to pass from the bore 74 via a bore 78 and into a bore 80. The water at the required temperature is then able to pass through the shower port 82. The bore 72 is blocked by a plug 84. The plugs 70, 84 ensure that the waterflow to the shower ports 14, 16 is always via the non-return check valves 62, 76.

The valve block 6 is such that there is considerable valve material in the form of the brass metal between the various bores for example in the areas 86, 88. This material is more than is found in cast valves, for example where the areas 86, 88 are typically largely hollow. In the valve block 6, the greater mass of material helps to stop temperature fluctuations which are a problem with cast valve blocks.

As noted in United Kingdom Patent No. 2547618, the process providing the machined metal valve block, for example made of brass, is not as cost-effective as the production of a straight-sided plumbing valve made by casting. Nevertheless, production by machining is not so much more expensive than the production by casting that the valve block cannot be produced commercially. The valve block produced by machining has the advantage that the machining produces smooth surfaces which are able to discourage the build-up of limescale. This enables the thermostatic shower valve to be offered with a guarantee of a considerably longer life than a thermostatic shower valve with a cast valve block. An increased life guarantee is commercially significant and this, together with the fact that the valve block is able to be produced at a cost which is not too much more than the cost of producing comparable valve block by casting, enables the valve block and the thermostatic shower valve to be produced to be commercially viable. Also, for the entire thermostatic shower valve, the increased costs for the valve block are advantageously offset by the lack of damage done to the environment.

It is to be appreciated that the embodiment of the invention described above with reference to the accompanying drawings has been given by way of example only and that modifications may be effected. Thus, for example, the thermostatic shower valve 2 may be of different construction to that shown in the drawings. Aluminium may be employed instead of brass. Individual components shown in the drawings are not limited to use in their drawings and they may be used in other drawings and in all aspects of the invention. The invention also extends to the individual components mentioned and/or shown above, taken singly or in any combination.

Claims (6)

1. CLAIMSA thermostatic shower valve comprising a thermostat and a valve block, and wherein: (i) the thermostat comprises a plurality of separate component parts which are releasably assembled together to form the thermostat; (ii) the thermostat formed by the assembled component parts does not have a thermostat housing; (iii) the thermostat is in a thermostat-receiving bore in the valve block; (iv) the thermostat-receiving bore is defined by a bore wall in the valve block; (v) the bore wall forms a housing for the thermostat; (vi) the valve block is a machined metal valve block; (vii) the valve block comprises inlet and outlet bores for enabling water to flow in and out of the valve block; and (viii) the inlet and outlet bores are machined inlet and outlet bores.
2. 2. A thermostatic shower valve according to claim 1 in which the valve block has straight sides.
3. 3. A thermostatic shower valve according to claim 1 or claim 2 in which the component parts of the thermostat comprise a return spring, a baffle, a piston, a thermostatic element, an over-travel spring housing, an over-travel spring plug, a screw plug, a spindle for on/off control of the thermostatic shower valve, and a main head member.
4. A thermostatic shower valve according to claim 3 in which the spindle is a non-rising spindle.
5. 5. A thermostatic shower valve according to claim 3 or claim 4 in which the thermostatic element comprises wax for providing travel of the thermostatic element and the piston.
6. 6. A thermostatic shower valve according to any one of the preceding claims in which the valve block is made of brass or aluminium.