GB2110340A

GB2110340A - Mixer tap assemblies

Info

Publication number: GB2110340A
Application number: GB08204480A
Authority: GB
Inventors: Joe Habermacher
Original assignee: KWC AG
Current assignee: Franke Technology and Trademark Ltd
Priority date: 1981-11-26
Filing date: 1982-02-16
Publication date: 1983-06-15
Also published as: JPS649506B2; CH654638A5; JPS5894683A; GB2110340B

Abstract

The mixing tap assembly has a cartridge housing 23 wherein is stationarily held a first ceramic plate 25 on which is rotatably arranged a second ceramic plate 26 serving the purpose of controlling the temperature by means of a handle lever 15a. On this second ceramic plate 26, a third ceramic plate 27 serving the purpose of controlling quantity, is arranged so that it may be displaced linearly by the handle lever 15a. The first inlet passage formed by inflow perforations of the ceramic plates 25, 26, 27 and connected to the hot water supply pipe 21b may be connected via a first branch duct 29b in a cover plate 29 and a first outlet passage formed by central outflow perforations of the ceramic plates to an inner pipe 22c of an outflow pipe 22. The second inlet passage formed by inflow perforations of the ceramic plates and connected to the cold water supply pipe 21a is then simultaneously connected via a second branch duct 29a in the cover plate 29 to a second outlet passage 41b extending outside the ceramic plates in the mixer housing 21 and leading into the cavity 22b of the outflow pipe 22. The total cross- section of the outlet passages may thus be adapted to the total cross- section of the inlet passages. <IMAGE>

Description

SPECIFICATION Improvements in or relating to mixer tap assemblies The present invention relates to one-lever mixing tap assemblies of the kind having a housing connectible to the cold and hot water supply systems which housing has a control unit carrying the actuation means, containing three ceramic plates situated one above another and provided with inlet passages for cold and hot water and with an outlet passage provided therein. Hereinafter such assemblies vvill be referred to as "of the kind described".

In known mixing tap assemblies of the kind described, in which temperature control is performed by turning the middle plate with respect to a first stationary plate and the quantity control is performed by linear displacement of a third plate with respect to the middle plate, a bypass duct is situated in or immediately above the third plate, is connected to the inlet perforations of the latter and into which also opens the outflow perforation of this third plate. The same may also be connected to the outflow passage formed by the outflow perforations of the other two plates, and via a connecting passage in the housing, to the outflow pipe. This has the result that cold and hot water are mixed actually within the outflow passage leading centrally through the plates, that is to say still within the control unit.The crosssection of this central outlet passage, which cannot be made as large as may be desired for a variety of reasons, then positively restricts the maximum possible quantity of water since it acts as a constrictor between the two inlet passages for cold and hot water and the outflow pipe which may always be selected comparatively large.

Where the pressures in the cold and hot water supply pipes differ considerably, for example as in England, and where it is consequently mandatory to lead the cold water flow and the hot water flow separately as far as the point of outflow spout (end of the outflow pipe), these known one-lever mixers cannot be utilised.

It is thus an object of the invention to avoid or minimise these disadvantages, and also to provide a mixer tap having as unitary a structure as possible, which may be adapted to all conditions encountered, by means of but few easily exchangeable parts.

Accordingly, in a mixer tap assembly of the kind described, the invention consists in that the one inlet passage allocated to the one water flow and formed by inflow perforations of the ceramic plates may be placed in communication via a first by-pass duct with a first outlet passage formed by outflow perforations in the ceramic plates and a housing passage, and in that the other inlet passage allocated to the other water flow and formed by inflow perforations of the ceramic plates may be placed in communication via a second by-pass duct with a separate second outlet passage formed outside the ceramic plates within the mixer housing, the two outlet passages opening into the outflow pipe via separate housing apertures.

Two outlet passages are thus available, the total cross-section of which may be adapted to the maximum total cross-section of the inlet passages with elimination of constrictors, without the ceramic plates themselves having to be provided with excessively large outflow perforations. On the other hand, the cold and hot water flows cannot already mix within the control unit, and this can occur only outside the mixer housing on the contrary, for example in the outflow pipe itself or, depending on its structure, or only at the end of the outflow spout.In one particularly advantageous embodiment, the two by-pass ducts are provided in a plastics material cover plate fixed on the linearly displaceable third ceramic plate serving the purpose of quantity control; the one by-pass duct constructed for an 1 800 deflection is then in communication with a central outflow perforation of the said third ceramic plate, whereas the other by-pass duct constructed for a 900 deflection opens radially out of the cover plate and into the other outlet passage. This other outlet passage may be formed by radial apertures in a carrying sleeve receiving the ceramic plates of the control unit and in the wall of the mixer housing, and rriay open directly into the outflow pipe situated on this housing.It may however also lead, within the mixer housing and parallel to the first outlet passage formed in the ceramic plates, to a housing aperture opening into the outflow pipe.

In order that the invention may be more clearly understood, reference will now be made to the accompanying drawings which show some embodiments thereof by way of example, and in which: Figure 1 shows a one-lever mixing tap assembly comprising a 3-plate control unit, in axial cross-section, Figures 2, 3 and 4 each show an embodiment having a different water guiding system, diagrammatically and in an axial cross-section displaced through 900 with respect to the crosssection according to Figure 1, Figures 5 and 6 each show a plan view of the middle ceramic plate serving the purpose of controlling temperature, in different positions with respect to the stationary ceramic plate, Figures 7 and 8 each show a plan view of the 3-plate stack of the control unit in different positions of the third ceramic plate serving the purpose of controlling quantity, with respect to the middle ceramic plate serving the purpose of controlling temperature.

Figures 9 and 10 show a first example of a quantity control plate comprising a superposed cover plate incorporating the by-pass ducts, in axial cross-section respectively in radial crosssection along the line I-I in Figure 9, Figures 11 and 1 2 show cross-sections analogous to Figures 9 and 10, showing the possibility of a different water guiding system by replacement of the cover plate, Figures 13 and 14 show a second example of a quantity control plate comprising by-pass ducts incorporating the latter in this plate itself in crosssection analogous to Figures 9 and 10, Figures 1 5 and 1 6 show cross-sections analogous to Figures 1 3 and 14, depicting the possibility of another water guiding system by replacement of the third plate, Figures 17 and 18 show an embodiment of the quantity limitation means in a different setting position in each case, in axial cross-section, and Figures 19 and 20 show an end view from above and below respectively, of the adjustable quantity limitation element according to Figures 17 and 18.

Referring now to the drawings the practical embodiment of a one-lever mixing tap assembly shown in Figure 1 comprises a mixer housing 1 in one piece with the outflow pipe 2. Inlet passages for cold and hot water, as well as a central outlet passage, are led through the base of the housing in a manner not illustrated herein in detail. In this cylindrical mixer housing 1 is situated a replaceable control unit (commonly referred to as control cartridge). This control unit has its cartridge housing 3 sealed from the outside and secured against twisting in the mixer housing 1.

The hollow neck 4a of a control sleeve 4 rotatable within the cartridge housing 3 projects through an upper delimiting ring 3a of the cartridge housing 3. A first ceramic plate 5 is held secured against rotation in the lower rim section of the cartridge housing 3, being the lower section in the drawing; this first ceramic plate 5 provided with inflow perforations not shown in detail and with a central outflow perforation, rests on a one-piece seal 8 enclosing the inflow and outflow passages in the base of the mixer housing 1 and held by a base plate 8a. A middle ceramic plate 6 serving the purpose of controlling temperature, which is corotatably connected to the lower rim section of the control sleeve 4 and provided with perforations, rests on the stationary ceramic plate 5.For its part, a third ceramic plate 7 serving the purpose of controlling quantity and being appropriately perforated, rests on this middle ceramic plate 6. A cover plate 9 of plastics material which is provided with by-pass ducts or the like, is firmly seated on this third ceramic plate 7. The form and arrangement of the perforations provided in the ceramic plates 5, 6 and 7, as well as the by-pass ducts incorporated in the cover plate 9 are also hereinafter described in detail.The cover plate 9 has a top recess 9a wherein engages the entraining element 1 Oa of an actuating bolt 10 journalled in limited pivotal manner in the neck 4a of the control sleeve 4 by means of a bearing spindle 1 or. A cap nut 11 secures the cartridge housing 3 in the mixer housing 1, whereas a plastics material covering ring 12 clipped on the neck portion of the cap nut 11 assured a dustproof seal between the cap nut 11 and the neck 4a of the control sleeve 4. The shank of the actuating bolt 10 is provided with teeth 1 3 and projections out of the neck 4a said teeth mating with a corresponding toothed quantity limitation element 14 hereinafter described in greater detail.

The free end section of the actuating bolt 10 carries a handle cowling 1 5 provided with a handle lever 1 5a and fitting over the covering ring 12, a fastening screw of which handle is situated below a removable covering cap 1 6 as shown. The control sleeve 4 and therewith the middle ceramic plate 6 (and thereby obviously also the top one) is turned with respect to the stationary ceramic plate 5 by pivoting the handle lever 15a around the axis of the actuating bolt 10, whereas the covering plate 9 and therewith the top ceramic plate 7, are displaced linearly on the middle ceramic plate 6 by pivoting the handle lever 15a around the axis of the bearing spindle 1 or. For perfect parallel displacement of this ceramic plate 7, the covering plate 9 is appropriately guided by means of rubber elements in grooves of the control sleeve 4.

Three possible modified embodiments are described in respect of a mixing tap assembly of the kind described in the foregoing, with reference to Figures 2 to 4. In these Figures 21, denotes the mixer housing comprising the supply pipes 21 a and 21 h for cold and hot water. The outflow pipe is shown at 22 and tightly surrounds the cylindrical mixer housing 21 by means of a connector sleeve 22a. The control unit replaceably installed in the mixer housing 21 has a cartridge housing 23 comprising a non-rotatably inset bottom ceramic plate 25 which bears on the seal 28 situated above the mixer housing base.The middle ceramic plate 26 which serves the purpose of controlling the temperature and is rotatably joined to the control sleeve 24 rotatable in the cartridge housing 23, is situated in the said control sleeve, and above the same is situated the upper ceramic plate 27 serving the purpose of controlling the quantity and carrying the plastics material cover plate 29, as described in particular with reference to Figure 1. The stationary ceramic plate 25 comprises inflow perforations 25a, 25b corresponding to the supply pipes 21, 21 b, as well as a central outflow perforation 25c.The rotatable middle ceramic plate 26 is provided with corresponding inflow perforations 26a, 26b and a central outflow perforation 26c, whereas the upper linearly displaceable ceramic plate 27 for its part has inflow perforations 27a, 27b and a central outflow perforation on a line transversely extending to the direction of displacement. The cross-sectional form of the perforations comprising axially parallel walls of the three plates 25, 26, 27 is apparent from Figures 5 to 8.

Whereas the outflow perforations 27a, b, c are identical and cylindrical, the inflow perforations 25a, b of the stationary ceramic plate 25 are sickle-shaped, in which connection and as apparent from Figure 6, which merely shows the hot water position of the ceramic plate 26, a rotation of this plate through approximately 1 200 brings the same into the position for cold water withdrawal only. On the other hand, the inflow perforations 26a, band 27a, b of the ceramic plates 26 and 27 have an identical cross-section of approximately parallelogram-shaped form.The size and arrangement of the two plates 26, 27 are so selected that upon displacing the top ceramic plate 27 from the open position (Figure 7) into the closed position (Figure 8) the inflow perforations 26a, 26b of the middle ceramic plate 26 are covered and thus closed a little earlier than the outflow perforation 26c. The upper linearly displaceable ceramic plate 27 carries the cover plate 29 coupled to move therewith. This cover plate 29 has two by-pass ducts or the like 29a and 29b at the side facing towards the ceramic plate 27. The by-pass duct 29a covers the inflow perforation 27a and is laterally open, as clearly apparent from Figure 1 0. On the contrary, the bypass duct 29b covers the inflow perforation 27b and also the outflow perforation 27c; it is sealed off from the outside by means of a seal 29c.The modified forms shown in Figures 2 to 4 differ fundamentally only in the nature and arrangement of the outflow passage connected to the outwardly open by-pass duct 29a of the cover plate 29.

As shown particularly in Figure 2, the control sleeve 24 as well as the cartridge housing 23 have wall openings 24c and 23c respectively, in the area of the lateral opening of the by-pass duct 29a of the cover plate 29, which are in communication with an annular groove 21 c in the mixer housing 21. From the annular groove 21 c, a housing passage 41 c leads outside the cartridge housing 23 into the base section of the mixer housing 21 and leads laterally into the outflow pipe 22 therein; an analogous passage 42c leads into the base section of the mixer housing 21 from the central outflow perforation 25c of the stationary ceramic plate 25, also to the outflow pipe 22.

Whereas the housing passage 41 c however leads directly into the cavity 22a of the outflow pipe 22, the housing passage 42c terminates in an inset pipe 22c traversing the outflow pipe 22; the cavity 22b and the inset pipe 22c lead in manner which is not illustrated to an outflow mouthpiece which is provided with two corresponding outlets.The form of construction described has the result that when the mixing tap assembly is open (to which end the ceramic plate 27 serving the purpose of controlling quantity more or less uncovers the inflow perforations 26a, 26b of the subjacently situated ceramic plate 26 with its inflow perforations 27a, 27h the inlet passage formed by the perforations 25a, 26a, 27a and connected to the cold water supply pipe 21 a is in communication via the by-pass or branch duct 29a with the outlet passage formed by the wall openings 24c, 23c, the annular groove 21 c and the housing passage 41 c and thus with the cavity 22b of the outflow pipe 22, whereas the inlet passage formed by the perforations 25b, 26b, 27h and connected to the hot water supply pipe 21 b is in communication with the outlet passage formed by the outflow perforations 27c, 26c, 25c via the by-pass or branch duct 29b and thus with the inset pipe 22c of the outflow pipe 22.

In the modified form shown in Figure 3 but otherwise corresponding to Figure 2, the by-pass or branch duct 29a leads via the wall opening 23c of the control sleeve 23 into an enlargement 44c of the cartridge housing 24, which opens into an annular passage 45c in the base of the mixer housing which for its part leads into the cavity 22b of the outflow pipe 22.

In the modified form shown in Figure 4 however, the annular groove 21 c of the mixer housing 21 connected to the branch duct 29a via the wall openings 24c and 23c of the control sleeve or of the cartridge housing 23, is connected directly to the cavity 22b of the outflow pipe 22 via a wall opening 46c of this housing.

In all three modified forms described, it is assured that when the mixing tap assembly is open, each of the two inlet passages leading through the ceramic plates is connected via a separate branch duct with an own outlet passage opening separately into the outflow pipe. Since one only of these outlet passages is formed by perforations in the ceramic plates, the total outflow cross-section of the mixing assembly may be adapted to the total inflow cross-section of the two supply pipes without undesirably large dimensions of the ceramic plates and thus of the mixer housing; constrictors such as are generally provided in prior art constructions, and comprising a single outlet passage only, which is led through the ceramic plates, are eliminated or substantially eliminated in this case without any difficulty.It is assured moreover that due to the absolute separation of the two water flows up to ingress into the outflow pipe, this separation may be maintained as far as the outflow spout (e.g. as specified in England), or cancelled immediately upon entering the outflow pipe (as customary in Switzerland). One and the same mixer housing having an inset control unit is utilisable in both cases, an outflow pipe comprising an inset pipe being utilised in the one case, and one lacking an inset pipe being utilised in the other case.

Although it proved to be advantageous for the cover plate 29 provided with branch ducts 29a, 29b to be produced as a separate plastics material component, it is perfectly possible to produce this plate comprising the branch ducts from ceramic material and to make use of the same simultaneously as a quantity control plate, i.e. by placing the same directly on the temperature control plate 6 and 26 respectively. A modified form of this kind is illustrated in Figures 13 and 1 4. As apparent therefrom, the total height of the ceramic plate 49 provided with the branch ducts 49a, 49b may be selected to correspond precisely to the sum of the heights of the plates 27 and 29, i.e. there is no need for any modifications to the other structural elements of the mixing tap assembly. It should also be observed that the satisfactory adhesion between the two ceramic plates 26,49 renders it superfluous to interpose a seal enflanking the branch duct 49b. Such a mode of construction combining the quantity control plate with the cover plate comprising the branch ducts is appropriate in particular in cases in which lesser requirements are applied regarding noise damping in the area of the branch ducts, although sound-damping inserts could also be incorporated in this case if desired. In the embodiment comprising a plastics material cover plate, sound damping elements, e.g. studs or finds, may be made in one piece with the plate.

The described form of construction of the mixing tap assembly with its water guiding action leading separately up to the outflow pipe which as demonstrated may cope with the most diverse requirements by replacement of but few elements, may however also be converted in quite analogous manner into a mixing tap assembly with a conventional water system, that is with a mixing chamber formed in the control unit itself by means of a single branch passage. Figures 11 and 12 show a plastics material cover plate 59 which comprises a single and outwardly omnilaterally closed branch or by-pass duct 59a and which may be incorporated as a replacement for the cover plate 29.With this cover plate 59, the outlet passage extending outside the ceramic plates of the modified forms shown in Figures 2 to 4 remains unused, i.e. hot and cold water leave the control unit actually through the same outlet passage leading centrally through the ceramic plates. Similarly, the ceramic plate 49 serving the purpose of controlling quantity and of deflection according to Figures 1 3 and 14, may be replaced by a ceramic plate 69 comprising an outwardly closed branch duct 69a (Figures 1 5, 1 6) allocated to both inflow perforations 26a, 26b and to the outflow perforation 26e of the subjacently situated ceramic plate 26.The second outlet passage which is then a dead-end, does not in any way impede the operation of the control unit or rather the traversal by water as far as into the outflow pipe 22.

As stated, hereinabove described embodiments of mixing tap assemblies according to the invention render it possible to adapt the total outlet passage cross-section in the mixer housing to the maximum possible water infeed through the two supply pipes. It is desirable at present in many cases however to limit the quantity of water which is to be discharged to a smaller value than the maximum possible value. This may be accomplished in the mode of construction described in particular with reference to Figure 1 by appropriate limitation of the pivotal displacement from the closed to the open position of the actuating bolt 10. To this end, the limiting element 1 4 situated on the teeth 13 of the actuating bolt 10 is provided with a lower tapering end rim section which is supported radially as well as axially.In the example illustrated in accordance with Figures 1 7 to 20, four impingement steps 140, 141, 142 and 143 are formed by the said end rim gradation over a peripheral angle of approximately 1400, whereas the end rim section diametrically opposed to these impingement steps forms a non-stepped tapering surface. Thanks to the teeth 13, the limiting element 14 may be placed on the actuating bolt 10 at an optional rotational position, that is in such manner that one of the four impingement steps specified, 140, 141,142,143 (e.g. corresponding to the delimiting steps denoted by marks 0, 1,2 and 3) rests on the end rim of the neck 4a of the control sleeve 4 when the actuating bolt 10 is pivoted into the open position, as shown in Figure 1 8 for the impingement step 142 (position 2).As apparent from Figure 20, the step 140 does not result in any restriction on the open position, i.e. it allows of pivoting the actuating bolt 10 into a position in which the quantity control plate 7 and 27 respectively wholly uncovers the inflow crosssections of the inflow perforations of the subjacently situated ceramic plate 6 and 26 respectively, whereas the following steps 141, 142 and 143 uncover even smaller cross-sections and thereby correspondingly restrict the maximum possible water discharge quantity.

It is evident that reversible turn limiter stops may also be situated between the rotatable control sleeve and the stationary housing, which allow of a limitation of the hot water temperature adjustable by means of the ceramic plate 6 and 26 respectively, to a smaller value than the maximum possible value, by rendering total closure of the cold water inlet passage under simultaneous complete opening of the hot water passage more or less impossible.

Claims

1. A one-lever mixing tap assembly of the kind described, wherein the inlet passage allocated to the one water flow and formed by inflow perforations of the ceramic plates may be placed in communication with the first outlet passage formed by outlet passages in the ceramic plates and by a housing passage via a first by-pass duct and wherein the other inlet passage allocated to the other water flow and formed by inlet perforations of the ceramic plates may be placed in communication via a second by-pass duct with a separate second outlet passage formed outside the ceramic plates in the mixer housing, the two outlet passages opening into the outlet pipe via separate housing openings.

2. A mixing tap assembly as claimed in claim 1 and having a control unit which comprises a first ceramic plate held stationarily in a cartridge housing and situated above the base of the mixer housing, a second ceramic plate rotatable on the stationary ceramic plate by means of a control sleeve rotatably installed in the cartridge housing and serving the purpose of controlling the temperature, and a third ceramic plate serving the purpose of controlling the volume and linearly displaceable on the second ceramic plate, wherein the first by-pass duct is formed above or within the third ceramic plate by a radially closed plate excision, whereas the second by-pass duct is equally formed above or within the third ceramic plate by a radially outwardly open plate excision.

3. A mixing tap assembly as claimed in claim 2, wherein the second outlet passage is in communication with the radial opening of the second by-pass duct via a radial wall aperture of the control sleeve.

4. A mixing tap assembly as claimed in claim 3, wherein the second outlet passage is formed by an enlargement of the cartridge housing leading axially to the housing base of the mixer housing, which is connected at one end to the wall opening of the control sleeve and at the other end via a passage in the mixer housing base to the cavity of the outflow pipe.

5. A mixing tap assembly as claimed in claim 3, wherein the second outlet passage is formed by an inner annular groove of the mixer housing, which is connected at one end via a wall opening in the cartridge housing to the wall opening of the control sleeve and at the other end via a passage leading through the base of the mixer housing to the cavity of the outflow pipe.

6. A mixing tap assembly as claimed in claim 3, wherein the second outlet passage is formed by a wall opening of the mixer housing leading into the cavity of the outflow pipe, which is connected via a wall opening of the cartridge housing to the wall opening of the control sleeve.

7. A mixing tap assembly as claimed in any of claims 2 to 6, wherein the inlet and outlet perforations of the ceramic plates have axially parallel walls, the inlet perforations of this plate arranged symmetrically with respect to the central outflow perforation of the stationary ceramic plate having a sickle-shaped cross-section whereas the inlet perforations of these plates which are equally arranged symmetrically with respect to the central outflow perforation of the second and third ceramic plates have a subsstantially identical parallelogram-shaped cross-section.

8. A mixing tap assembly as claimed in any of claims 2 to 7, wherein the plate comprising the by-pass ducts has an upper recess in which engages an entraining element of the actuating bolt carrying the hand lever which actuating bolt is pivotally mounted in the hollow neck of the control sleeve by means of a bearing spindle.

9. A mixing tap assembly as claimed in any of claims 2 to 8, wherein the two by-pass ducts are provided in a plastics material cover plate coupled to move with a ceramic plate serving the purpose of controlling quantity.

10. A mixing tap assembly as claimed in any of claims 2 to 8, wherein the two by-pass ducts are situated in the third ceramic plate simultaneously serving the purpose of controlling quantity.

11. A mixing tap assembly as claimed in claim 8, wherein the shank of the actuating bolt projecting out of the neck of the control sleeve has teeth which mate with a correspondingly toothed reversible delimiting member the lower end rim of which is stepped radially and axially, the impingement steps so formed being intended to establish the maximum possible pivotal displacement around the axis of the bearing spindle of the actuating bolt in the opening direction for co-operation with the end rim of the control sleeve neck.

12. A mixing tap assembly as claimed in any of the preceding claims wherein the outflow pipe encircles the cylindrical mixer housing with a connector pipe.

13. A mixing tap assembly as claimed in claim 12, wherein the first outflow passage is connected to an inner tube situated in the cavity of the outflow pipe and leading to the opening of the latter, whereas the second outflow passage leads direct into the cavity of the outflow pipe also leading to the outflow pipe opening.