GB2050157A

GB2050157A - Shower heads

Info

Publication number: GB2050157A
Application number: GB8013194A
Authority: GB
Original assignee: Tacchi P G
Current assignee: Tacchi P G
Priority date: 1979-04-27
Filing date: 1980-04-22
Publication date: 1981-01-07
Also published as: GB2050157B

Abstract

A shower head for use in a domestic installation wherein the shower head is at the end of a flexible tube and can be held in the hand, the shower head having a body (10) whereof the interior is formed as a mixing chamber for mixing together hot and cold water, there being a mixing valve (23, 26) supplied separately with hot and cold water via concentric pipes connected to a manifold (13) and controlled by a thermostat (31) and a cam (33) operated by a manual control knob. A positive shut-off for the valve is provided by a wedge plate (37), acting on the valve plate (26), and connected to the thermostat (31). <IMAGE>

Description

SPECIFICATION Improved shower fitting Description of Invention This invention relates to a shower fitting of the type which mixes hot and cold water to provide a supply of warm or hot water as well as cold water and in which the shower head from which the spray emerges is in the form of an elongated body which at, or adjacent, one end has a connection for the inlet of water and at the other end, has the spray head from which the jets of water emerge.

Such a shower fitting is hereinafter referred to as being "of the type specified".

As used hitherto, the shower fitting is generally mounted in some form of bracket on a wall so that it can be used in this position or it can be detached from the bracket for use and the elongated body then forms a handle by which the shower head can be grasped and moved freely about after having been detached from the supporting bracket.

In some cases, the hot and cold water are mixed in a valve which is remote from the shower head and which contains the mechanism for thermostatic control of the hot and cold water (if such is provided). This valve is generally mounted ori the same wall as the bracket for the shower head or on a closely adjacent wall. Such valve, which is generally connected to the shower head by a flexible metallic or plastics material tube, projects out into the area of the shower cabinet where it can prove an awkward obstacle for the user of the shower. Such problem also exists where the arrangment does not have a mixing valve but simply has two separate taps for controlling the hot and cold water supplies.Attempts to overcome the problem have so far involved making a suitable recess in the wall of a shower cabinet so that the whole of the mixing valve body (or the two taps) can be accommodated in such recess but this considerably increases the overall cost of the shower installation.

It has also been proposed to position the mixing valve, or the two taps, outside the shower cabinet area, such as on the remote side of a shower curtain, but this makes the control difficult for the user to reach.

One object of the invention is to provide an improved form of shower fitting which overcomes this problem.

According to the invention I provide a shower head for a shower fitting of the type specified wherein the body of the shower head is of elongated form having a spray head at or adjacent one end and inlets for hot and cold water at or adjacent the other end, the body being formed internally so as to provide a mixing chamber for the mixing of hot water and cold water, which chamber communicates with the spray head, there being located in or on the body valve means which control the supplies of hot and cold water to said mixing chamber.

Said valve means may be wholly manually operated or it may be thermostatically controlled and including a temperature responsive device which is under the influence of the temperature of the water mixture and which operates a movable valve member to control the proportions of hot and cold water entering the mixing chamber.

As the body is of elongated form, the movable valve member may be arranged for linear sliding movement in the body in the direction of the length of the body and may conveniently be in the form of a flat plate provided with control ports and having sliding engagment with the flat face or faces of a valve block which has supply ports therein connected to the inlets for hot water and cold water.

In a device where hot water is mixed with cold water from public mains, it is required that there should be positive means for isolating one feed from the other, when the device is not in use, and in the case of a shower flitting, this means the fitting of manually operated stop cocks in the two supply devices to the mixing valve (which is remote from the shower head) unless a positive shut-off valve means can be incorporated in the mixing valve itself. This latter expedient is difficult to satisfy in practice because when the shower head is in its static position (on its bracket) and not in use, there is a static head of the order of about 4 feet of water remaining in the pipe between the valve and the shower head and this can cause leakage past the shut-off valve.

With a shower head according to the present invention, when in the static position, there is very little head of water remaining (possibly 2 inches or less) and thus more favourable conditions for a positive shut-off valve to function satisfactorily.

A further aspect of the invention is the provision of positive shut-off valve means within the confined space of a shower head and according to this aspect of the invention there is provided a wedge plate engaging said flat plate which has the control ports, on the side of said flat plate remote from the valve block, the wedge plate being slidable in relation to the valve block so as to apply pressure, by means of a wedging action, to said flat plate to press the plate against the said flat face or faces of the valve block.

An embodiment of the invention is hereinafter described with reference to the accompanying drawings which are of a diagrammatic nature and wherein: Figure 1 is a perspective view showing the exterior shape of one form of shower head; Figures 2 and 3 are fragmentary views showing alternative positions for the actual spray head; Figure 4 is a view in side elevation showing the interior mechanism including thermostatic control and positive shut-off means; Figures 4a, 4b and 4c are diagrammatic views showing different positions of the valve control plate; Figure 5 is a detail view to illustrate the position where the wedge plate is in the fully shut-off position; Figure 6 is a detail view of the inlet manifold; Figure 7 is a top plan view on Fig. 6; Figure 8 is a bottom plan view on Fig. 6; and Figure 9 is a detail plan view of the valve block, looking from above in Fig. 4; Figure 10 is a fragmentary view showing additional details of the valve construction; Figure lOa is a fragmentary perspective view of the face of the valve body.

Referring to Fig. 1, the body 10 of the shower head is of generally elongated form and of such external dimensions as to enable the user to easily hold it in the hand and in the form shown in Fig. 1, the actual spray head is indicated at 11 at the one end of the body with the direction of the outcoming spray indicated by the arrow. A manual control knob 1 2 is positioned adjacent the spray head 11 and the inlet manifold 1 3 is positioned adjacent the opposite end of the body with a common inlet tube 14 for the supply of hot and cold water connected to the manifold 13.

In the alternative arrangement of Fig. 2, the manual control knob 1 2 is combined with the spray head 11 at the one end of the body and in another possible arrangment shown in Fig.

3, the spray head 11 is arranged adjacent the end of the body with the manual control knob 1 2 positioned at the extreme end of the body.

Referring now to Figs. 4 to 9, the outline of the body 10 is indicated by the chain dotted lines in Fig. 4, which view is arranged so that the shower head is shown in an upright and inverted position, the inlet manifold 1 3 being at the top and the manual control knob 1 2 and spray head 11 (not shown in Fig. 4) being at the bottom.The inlet manifold 1 3 comprises two concentric tubes, there being an outer tube 1 5 and an inner tube 16, with an annular space 1 7 between these two tubes and the flexible pipe 14 which conveys the hot and cold water from the supplies to the shower head is also of concentric construction, having an outer tube and an inner tube with an annular space therebetween so that one fluid can flow along the annular space and the other fluid along the inner tube. In the example shown, the cold water supply is connected to the outer tube so that cold water flows through the annular space and eventually through the annular space 1 7 of the manifold and hot water flows through the inner tube and eventually through the central tubular portion 1 8 of the manifold.

The manifold 1 3 may be formed integrally with the body 10 (e.g. as a moulding in plastics material) or it may be a separate part which is fitted to the body. Within the body the manifold has a part 1 9 of square form and in the case where the manifold is formed separately from the body, a suitable sealing gasket 20, as shown in Fig. 9, would be provided between the part 1 9 and the opening in the wall of the body 10. As shown in Fig. 7, the part 1 9 of the manifold is formed with two cold water passages 21 extending therethrough and communicating with the cold water space 1 7 and a common hot water passage 22 communicating via a central passage in the part 1 9 with the central hot water inlet 18.

The mixing valve body 23 is secured to the part 1 9 of the inlet manifold by the use of a number of screws, one of which is shown at 24 in Fig. 9, and the valve body 23 has four separate ports extending therethrough, two of which communicate with the cold water passages 21 in the part 1 9 of the manifold and the other two of which communicate with the common hot water passage 22 in the part 1 9.

Such ports are indicated at 25 in Fig. 4 and Fig. 9, and in the diagrammatic view of Figs.

4a to 4c, the ports are designated by the letter C which indicate cold water ports and H to indicate hot water ports.

A valve control plate 26, which is of flat form, is mounted within the valve body 23 in sliding engagement with the flat face of the valve block to which the ports 25 extend, and as shown in Figs. 4a to 4c, the valve control plate 26 is provided with four apertures each of square form and arranged in two pairs, there being two apertures 27 for co-operation with the hot water ports 25 in the valve block and two apertures 28 for co-operation with the cold water ports 25 in the valve block.

Near its one end, the valve control plate 26 has an aperture 29 through which projects a peg 30 connected to the one end of the body of a temperature responsive thermostat device generally indicated at 31, and at its opposite end the body of the thermostat 31 has an abutment plate 32 which bears against the periphery of a cam comprising a circular disc 33 mounted eccentrically about an axis of rotation 34, with the manual control knob 1 2 being connected to the cam 33 and also rotatable about the axis 34. The body of the thermostat 31 is urged resiliently into contact with the periphery of the cam 33 by means of a coil spring 35 engaging the abutment plate 32 at one end and engaging a fixed abutment (not shown) within the body 10 at its other end. The temperature responsive thermostat device 31 may be of generally known form such as a waxfilled capsule or bellows, or known form of linear bimetallic device having the characteristic that increase in temperature results in corresponding increase in the effective overall length of the device 31, there being a corresponding contraction in overall effective length upon decrease in temperature.

Such temperature responsive devices are well known and further description is not considered necessary.

The valve block 23 is completed by a cover plate 36 secured to the projecting side of the valve block by the screws 24 so as to leave a space between the inside face of the cover plate 36 and the valve control plate 26, such space being of rectangular cross-sectional area and having fitted therein a wedge plate 37 which has one flat face in sliding engagement with the one face of the valve control plate 26 and has its tapered face in engagement with a correspondingly tapered face formed on the inside of the cover plate 36. At its larger cross-section end, the wedge plate 37 has connected thereto a coil spring 38 which at its other end is connected to a fixed member within the body 10 so that the wedge plate 37 is urged resiliently in the direction towards the axis 34 of cam 33, which is the downwards direction as seen in Fig. 4.

At its end remote from the spring 38, the wedge plate 37 has an elongated slot 39 extending in the direction of its length and engaging over the projecting peg 30.

From the above it will be appreciated that the hot water and cold water entering via the manifold 1 3 passes through the passages 21 and 22 in the manifold and then through the separate hot water and cold water ports 25 in the valve block 23 and then into the interior of the body 10 when the valve control plate 26 is in a partially open or fully open position where the hot water mixes with the cold water to provide a warm or hot water mixture which exits through the spray head 11. In the position of the part shown in Fig. 4, the valve control plate 26 is in the position of Fig. 4a so that the valve is in the fully shut-off position.

To operate the mixing valve of the shower head from this fully shut-off position, the manual control knob 1 2 is turned so as to rotate the cam 33 and allow the spring 35 to urge the thermostat device 31 in the downwards direction as seen in Fig. 4, so as to move the valve control plate 26 from the fully shut-off position of Fig. 4a to a first intermediate position as shown in Fig. 4b in which the two ports 28 in the valve control plate are in full register with the two cold water ports in the valve block, with the hot water ports 27 of the control plate being out of register with their corresponding hot water ports in the valve block so that a supply of cold water is obtained from the spray head.Further movement of the manual control knob in the same direction will bring the valve control plate 26 to the fully open position shown in Fig. 4c where only the hot water ports 27 are in register with their corresponding ports in the valve block, the cold water ports being out of register so that a supply of hot water at maximum temperature is available.

In use, a position somewhat between Fig.

4b and 4c can be selected to provide a discharge of warm water at a desired temperature and having reached such selected position, the position of the valve plate 26 in relation to the valve block 23 is maintained by the thermostat device 31 which moves in the appropriate direction to alter the position of the valve control plate 26 in response to any increase or decrease in temperature of the water mixture.

It will be appreciated that once the manual control is operated to move the valve plate 26 from the fully closed position of Fig. 4a, the pressure exerted by the wedge plate 37 is reduced and there is only a minimum amount of frictional resistance to movement of the plate 26 over the range from fully closed to fully open. Such frictional resistance to movement can be further reduced by the choice of suitable materials for the valve block 23, valve control plate 26 and wedge plate 37.

As seen in Fig. 5, the wedge plate 37 has projecting shoulders 40 which are for the purpose of limiting the travel of the wedge plate 37 from the fully shut-off position (Figs.

4 and 4a). During the opening operation of the valve when the wedge plate reaches the position corresponding to Fig. 4b, the shoulders 14 engage the valve block 23 to prevent a further movement of the wedge plate and then in between the position of Figs. 4b and 4cthe peg 30 can move freely in the slot 39 of the wedge plate until the manual control knob is again operated to shut off the valve when the peg 30 engages the end of the slot 39 and positively moves the valve plate 26 and wedge plate 37 towards the shut-off position, and also ensures the positive wedging action of the wedge plate 37 to firmly press the valve control plate 26 into sealing engagement with the cooperating face of the valve block 23.

The requirement for a positive shut-off and isolation of the hot and cold water supplies is thus satisfied and, as explained hereinbefore, as there is only a minute head of static water likely to remain in the body 10 when it is in its static position there is unlikely to be any leakage through the valve of such remaining water. Such possibility can be further reduced by providing a pin hole at the underside of the body 10 as shown in Fig. 1 to allow any such remaining water to drain away. During operation such pin hole would be covered by 'the hand of the user and no water would escape therefrom. An alternative arrangement would be to have a valve (e.g. a ball valve) opening in the position where a head of water could exist, i.e. gravity operated.

The spring 38 acting on the wedge plate 37 ensures that when the mixing valve is operating the wedge plate will be moved to the position corresponding to Fig. 4b where it is arrested by engagement of the shoulders 40 and is thus always, during operation, in the position which offers minimum of frictional resistance to movement of the valve control plate 26.

Referring now to Fig. 10, there is shown there a preferred practical feature of the construction of the valve in the form of a pad 42 of resilient material interposed between the heads of the securing screws and the plate 41 having the inclined surface which is opposite the wedge plate 37. An outer cover plate 43 is provided beneath the heads of the screws and the presence of the resilient pad 42 ensures that when the valve is assembled a known force is exerted through the wedge plate 37 upon the valve control plate 26. This arrangement also provides compensation for wear without changing the linear relationship of the sliding parts.

in practice it may be found difficult to ensure that there is a perfectly flat surface on the -ported face of the valve block 23 which is engaged by the control plate 26 and to overcome this problem the construction shown in Figs. 10 and 1 Oa may be used wherein the port openings are constituted by locally raised collars 25a, the outer faces of which can be formed accurately in a common plane and thus the flatness of the remaining area of this face of the valve block is not critical. Instead of collars raised from the face of the valve block, "0" rings could be used, inserted in said face.

In order to ensure that the pressure exerted on the collars 25a by the control plate 26 is evenly distributed over all four, the inclined face of the top plate 41 may have a partspherical projection 44 which engages the wedge plate 37, the projection 44 being positioned so that its point of engagement with the wedge plate 37 is centrally located equidistant from the axial centre lines of all four collars 25a.

In an alternative arrangement the control of operation of the wedge plate may be separated from that of the control plate 26 by providing a second cam, on the same shaft as the cam 33, to control the wedge plate; this will allow for designing independent cam dwells as required.

Claims

1. A shower head for a shower fitting of the type specified wherein the body of the shower head is of elongated form having a spray head at or adjacent one end and inlets for hot and cold water at or adjacent the other end, the body being formed internally so as to provide a mixing chamber for the mixing of hot and cold water, which chamber communicates with the spray head, there being located in or on the body valve means which controls fhe supplies of hot and cold water to said mixing chamber.

2. A shower head according to Claim 1 wherein said valve means is wholly manually operated.

3. A shower head according to Claim 1 wherein said valve means is thermostatically controlled, including a temperature responsive device which is under the influence of the temperature of the water mixture and which operates a movable valve member to control the proportions of hot and cold water entering the mixing chamber.

4. A shower head according to Claim 3 wherein the movable valve member is arranged for linear sliding movement in the body in the direction of the length of the body.

5. A shower head according to Claim 4 wherein the movable valve member is in the form of a flat plate provided with control ports and having sliding engagement with a flat face or faces of a valve block which has supply ports therein connected to the inlets for hot water and cold water.

6. A shower head according to Claim 5 wherein the supplies of hot water and cold water are through pipes connected to a manifold which has passages therein to convey the hot and cold water separately to the valve block.

7. A shower head according to Claim 5 wherein one end of the flat plate is connected to one end of a linearly expandable and contractible temperature responsive thermostat device, the other end of which is in engagement with means connected to a manually operable control knob on the body of the shower head.

8. A shower head according to Claim 5 or Claim 7 wherein there is provided a wedge plate engaging said flat plate which has the control ports, on the side of said flat plate remote from the valve block, the wedge plate being slidable in relation to the valve block so as to apply pressure, by means of a wedging action, to said flat plate to press the plate against the said flat face or faces of the valve block.

9. A shower head according to Claim 8, when dependent upon Claim 7, wherein one end of the wedge plate is connected to the said one end of the thermostat device so that the wedge plate is moved positively in the direction to wedge the said flat plate in the valve-closed position when the manual control knob is moved to the off position.

10. A shower head according to Claim 7 wherein the said other end of the thermostat device is urged resiliently into engagement with a rotatable cam which is connected to a manually operable control knob on the body of the shower head.

11. A shower head substantially as hereinbefore described with reference to and as shown in the accompanying drawings.