GB2579183A - Disc valve assembly - Google Patents

Abstract

A disc valve assembly 16 comprises a valve housing 12 having a plurality of fluid-flow ports A, B, C, D and a disc valve sub-assembly 22 positioned to divide the valve housing 12 into first and second valve chamber regions 18a, 18b. The disc valve sub-assembly 22 comprises a first disc 24 having first and second primary apertures 28a, 28b and at least one secondary aperture 30 therethrough; a second disc 26 having at least three main apertures 46 therethrough; and a flow-diverter cover 32 engagable with the first disc 24 to fluidly connect the first and second primary apertures 28a, 28b to one another. A relative rotational position of the first and second discs 24, 26 is adjustable to selectively form a first fluid-flow pathway between a selected pair of the plurality of fluid-flow ports which extends through two of the main apertures 46 and the first and second primary apertures 28a, 28b, and a second fluid-flow pathway between a different selected pair of the plurality of fluid-flow ports which extends through at least one other of the main apertures 46 and the or each secondary aperture 30.

Description

Disc Valve Assembly The present invention relates to a disc valve assembly, particularly but not necessarily exclusively for use in automotive cooling systems. A flow diverter apparatus having such a disc valve assembly is also provided, as well as an automotive cooling system utilising the flow diverter apparatus. A method of controlling the flow between adjacent fluid-flow ports of a flow diverter apparatus is also provided.

As more complex cooling systems are developed for automotive contexts in view of the increased usage of hybrid electric technology, there is a requirement to provide valve control for the cooling systems which is effective and efficient, without compromising 10 the fluid-tightness of the system.

At present, there is a limited range of choices for multi-way valves. Multi-way ball valves are available, but these are bulky and relatively expensive to manufacture as a result of the precision required to create a fluid-tight seal. Additionally, such ball valve arrangements also typically require a plurality of actuators to control each ball individually, which further increases the complexity and manufacture of such an apparatus.

Furthermore, in order to provide suitable fluid-tightness, existing valves must be produced as a single unit. This limits the utility of multi-way valves, since a bespoke valve arrangement must be created for each different application.

The present invention seeks to provide a disc valve assembly which overcomes these issues.

According to a first aspect of the invention, there is provided a disc valve assembly comprising: a valve housing having a plurality of fluid-flow ports; and a disc valve subassembly positioned to divide the valve housing into first and second valve chamber regions; the disc valve sub-assembly comprising: a first disc having first and second primary apertures and at least one secondary aperture therethrough; a second disc having at least three main apertures therethrough; and a flow-diverter cover engagable with the first disc to fluidly connect the first and second primary apertures to one another; wherein a relative rotational position of the first and second discs is adjustable to selectively form a first fluid-flow pathway between a first two of the plurality of fluid-flow ports which extends through two of the main apertures and the first and second primary apertures, via the flow-diverter cover, and a second fluid-flow pathway between a second two of the plurality of fluid-flow ports which extends through at least one other of the main apertures and the or each secondary aperture.

The provision of a valve which can create two separate fluid-flow pathways connecting adjacent fluid-flow ports allows for the straightforward and selective distribution of fluid around a complex system, such as an automotive cooling system for a hybrid vehicle. Advantageously, this complex flow arrangement can be achieved via a single drive source, thereby reducing the number of components required to construct the assembly, and creating a more compact and cost-effective product.

Preferably, the flow-diverter cover may be releasably engagable with the first disc.

By making the flow-diverter cover as separate component to the first disc, the manufacturing complexity of the assembly can be reduced. In particular, the flow-15 diverter cover may not be most readily formed from the ceramic material of the first disc.

Optionally, the flow-diverter cover may comprise at least one engagement member for engaging with the first disc. Preferably, the engagement member may be provided as a spigot or receiver on the flow-diverter cover which is engagable with a corresponding 20 spigot or receiver on the first disc.

A suitable engagement member, such as a spigot and receiver combination, may allow for a simple snap-fit or clip-together construction of the disc valve sub-assembly.

Preferably, the first disc may be a movable disc, and the second disc may be a static disc.

The provision of one movable disc and one static disc allows for the selective control of 25 the fluid-flow pathways to be achieved using a single actuator, reducing the cost and complexity of the assembly.

The disc valve assembly may further comprise a drive shaft which is engagable with the flow-diverter cover to provide motive force to the first disc.

Since the flow-diverter cover is directly engaged with the first disc, it may act as a suitable transmission for motive force from a drive shaft to permit simple rotation of the first disc in spite of the intermediate positioning of the flow-diverter cover.

Optionally, the flow-diverter cover may be eccentrically positioned on the first disc, and 5 the drive shaft may be an eccentric drive shaft.

An eccentric flow-diverter cover provides sufficient space for fluid-flow around the outside thereof, so as not to interrupt or disrupt the flow entering into the first valve chamber region of the assembly. An eccentric drive shaft may be required to counteract this eccentricity.

In an alternative embodiment, the flow-diverter cover may be eccentrically positioned on the first disc, the drive shaft engaging with the flow-diverter cover along an axis of rotation of the movable disc.

A centrally engaged drive shaft significantly simplifies the driving of the first disc, and this can be accommodated even where the flow-diverter cover is eccentrically 15 positioned.

The flow-diverter cover may include a shaft receiver, the drive shaft being engagable with the shaft receiver.

A receiver on the flow-diverter cover may be a simple connection means between the actuator and the flow-diverter cover, and may also assist with urging the flow-diverter 20 cover against the first disc and corresponding seal.

Preferably, the disc valve assembly may further comprise biasing means for biasing the flow-diverter cover against the first disc.

It is important that a fluid-tight seal is made between the flow-diverter cover and the first disc, and therefore a biasing means to urge the flow-diverter cover against the 25 surface of the first disc to maintain the seal may be highly useful.

Optionally, the drive shaft may comprise a support element against which the biasing means is seatable to provide a biasing force to the flow-diverter cover.

A support element on the drive shaft may provide a suitable seat against which a biasing means can act without needing to rely on a particular internal shape of the valve housing itself Preferably, the valve housing may comprise four said fluid-flow ports.

Four fluid-flow ports is an optimum arrangement, since there will always be two pairs of ports which can be joined together along the first and second flow pathways.

In one embodiment, there may be one upper said fluid-flow port which corresponds with the secondary aperture of the first disc, and three lower said fluid-flow ports, each of which corresponds with one of the three main apertures of the second disc.

A two-plane fluid-flow port arrangement may be suitable wherein fluid is diverted to many different components which may well be vertically offset to one another, and therefore such a configuration may be well-suited to retrofitting into existing systems.

In an alternative embodiment, the four said fluid-flow ports may be co-planar, each of the four said fluid-flow ports corresponding with one of four said main apertures of the second disc, and wherein there are two said secondary apertures in the first disc, the second fluid-flow path being diverted into and out of the first valve chamber region via the two secondary apertures.

A completely planar port arrangement may be advantageous, as it may allow a more compact disc valve assembly to be created. This may allow the assembly to be installed 20 in situations where it would otherwise not be possible due to volumetric constraints.

The first fluid-flow path and second fluid-flow path may be selectably formable between any two adjacent pairs of fluid-flow ports of the disc valve assembly.

The advantage of the present system is that it allows any adjacent ports to be paired, according to user need, and therefore the user is not limited to a few pre-defined fluid-25 flow pathways based on the internal geometry of the valve.

Preferably, each of the first and second primary apertures may be formed as an overlapping section of the flow-diverter cover with a main aperture. Preferably, the or each second aperture may be formed as an arcuate aperture.

The shaping of the various apertures may be optimised for flow characteristics, so that 5 fluid flow is disrupt as little as possible in the transition between the various fluid-flow ports.

The flow-diverter cover may preferably be formed as a domed element.

A domed element provides a suitable cap which can enclose and form a fluid pathway between the first and second primary apertures to create the first fluid flow pathway 10 within the assembly.

Preferably, the flow-diverter cover may comprise a hemispherical or substantially hemispherical inner surface which faces the first and second primary apertures.

A hemispherical inner surface allows for redirecting of the flow inside the flow-diverter cover with a minimum turbulence, since the fluid can follow the natural curvature of the 15 cover.

Optionally, a plurality of said flow-diverter covers may be provided.

For the arrangement in which all of the ports are co-planar, the flow on each of the first and second fluid-flow pathways is diverted back on itself In this instance, a dual-cover, or bifurcated-cover arrangement might be advantageous so as to isolate the fluid in the disc valve assembly from the drive shaft and/or biasing means. This may be particularly useful where corrosive or reactive fluids are used, for instance.

According to a second aspect of the invention, there is provided a flow diverter apparatus comprising a disc valve assembly in accordance with the first aspect of the invention and an actuator for providing a driving force to adjust the relative rotational 25 position of the first and second discs of the disc valve assembly.

Only a single actuator is required to drive the present disc valve assembly, which reduces the cost and manufacturing complexity of a flow diverter apparatus having such an assembly.

According to a third aspect of the invention, there is provided an automotive cooling 5 system comprising a flow diverter apparatus in accordance with the second aspect of the invention.

As cooling systems become more complicated, a simple valve coupling between various coolant pipes becomes increasingly important, and the present invention provides such as simple flow control scheme.

According to a fourth aspect of the invention, there is provided a method of controlling the flow between adjacent fluid-flow ports of a flow diverter apparatus, the method comprising the steps of: a] providing a first fluid-flow pathway through the flow diverter apparatus and a second fluid-flow pathway through the flow diverter apparatus using a disc valve assembly, wherein there is a flow-diverter cover positioned on the first fluid-flow pathway; b] selecting a first configuration of the disc valve assembly such that a first adjacent pair of fluid-flow ports is connected by the first fluid-flow pathway and a second adjacent pair of fluid-flow ports is connected by the second fluid-flow pathway; and c] selecting a second configuration of the disc valve assembly such that a third adjacent pair of fluid-flow ports is connected by the first fluid-flow pathway and a fourth adjacent pair of fluid-flow ports is connected by the second fluid flow pathway.

The present invention creates a flow-diverter apparatus that allows for selective connection of adjacent fluid-flow ports in a simple fashion by the use of the disc valve assembly.

The invention will now be more particularly described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a perspective representation of a first embodiment of a flow diverter apparatus having a disc valve assembly in accordance with the first aspect of the invention; Figure 2 shows an exploded perspective representation of the disc valve assembly of the flow diverter apparatus of Figure 1; Figure 3a shows a side view of the flow diverter apparatus of Figure 1, inclusive of the valve housing and actuator; Figure 3b shows a cross-section through line X-X of the flow diverter apparatus of Figure 3a; Figure 4a shows a diagrammatic perspective representation of the disc valve assembly of Figure 1; Figure 4b(i) shows a diagrammatic plan representation of the first disc of the 10 disc valve assembly of Figure 4a, with the position of the flow-diverter cover indicated in dashed lines; Figure 4b(ii) shows a diagrammatic plan representation of the second disc of the disc valve assembly of Figure 4a; Figure 4c(i) shows a diagrammatic representation of a fluid flow between the 15 ports of the disc valve assembly of Figure 4a in a first configuration; Figure 4c(ii) shows a diagrammatic representation of a fluid flow between the ports of the disc valve assembly of Figure 4a in a second configuration which is different to that of Figure 4c(i), following rotation of the first disc by 120°, Figure 4d(i) shows a diagrammatic plan representation of the first disc of the 20 disc valve assembly as shown in Figure 4b(ii), with the position of main apertures of the second disc being indicated with dashed lines, when in the first configuration as shown in Figure 4c(i); Figure 4d(ii) shows a diagrammatic plan of the first disc of the disc valve assembly as shown in Figure 4b(ii), with the position of main apertures of the second 25 disc being indicated with dashed lines, when in the second configuration as shown in Figure 4c(ii); Figure 5a shows a perspective representation of a second embodiment of a flow diverter apparatus having a disc valve assembly in accordance with the first aspect of the invention; Figure 5b shows a plan view of the flow diverter apparatus of Figure 5a; Figure 5c shows a side view of the flow diverter apparatus of Figure 5a; Figure 6a shows a diagrammatic perspective representation of the disc valve assembly of the flow diverter apparatus of Figure 5a; Figure 6b(i) shows a diagrammatic plan representation of the first disc of the disc valve assembly of Figure 6a, with the position of the flow-diverter cover indicated 10 in dashed lines; Figure 6b(ii) shows a diagrammatic plan representation of the second disc of the disc valve assembly of Figure 6a; Figure 6c(i) shows a diagrammatic representation of a fluid flow between the ports of the disc valve assembly of Figure 6a in a first configuration; Figure 6c(ii) shows a diagrammatic representation of a fluid flow between the ports of the disc valve assembly of Figure 5a in a second configuration which is different to that of Figure 6c(i), following rotation of the first disc by 90°; Figure 6d(i) shows a diagrammatic plan representation of the first disc of the disc valve assembly as shown in Figure 6b(ii), with the position of main apertures of the 20 second disc being indicated with dashed lines, when in the first configuration as shown in Figure 6c(i); Figure 6d(ii) shows a diagrammatic plan of the first disc of the disc valve assembly as shown in Figure 6b(ii), with the position of main apertures of the second disc being indicated with dashed lines, when in the second configuration as shown in 25 Figure 6c(ii); Figure 7a shows a side representation of the disc valve sub-assembly of the disc valve assembly of Figure 5a; Figure 7b shows a plan view of the disc valve sub-assembly of Figure 7a; Figure 8a shows a cross-sectional diagrammatic representation of the fluid-flow 5 pathways through the disc valve sub-assembly of Figure 7a; and Figure 8b shows a plan diagrammatic representation of the fluid-flow pathways through the disc valve sub-assembly of Figure 7b.

Referring to Figure 1, there is indicated a flow diverter apparatus, referenced globally at 10, which is suitable for diverting fluid flow between a plurality of inlet and/or outlet 10 ports. In the present embodiment, there are a total of four fluid-flow ports: a first, upper port A, and second, third and fourth, lower, ports B, C, D. The flow diverter apparatus 10 comprises a valve housing 12, which is preferably a two part housing 12a, 12b, with the first fluid-flow port A being engaged with the first valve housing part 12a, and the second, third and fourth fluid-flow ports B, C, D being engaged with the second valve housing part 12b. Preferably, the second, third and fourth fluid-flow ports B, C, D are co-planar, and are preferably uniformly spaced around the circumference of the second valve housing part 12b.

The valve housing 12 may be formed in a modular fashion, with the two valve housing parts 12a, 12b being introduced to one another and then sealed in place, for example, by 20 welding.

An actuator 14 is engaged with the valve housing 12, here positioned so as to couple to the first valve housing part 12a, and the actuator provides rotational drive along a central axis of a disc valve assembly 16 of the flow diverter apparatus 10, which is shown in Figure 2, with the valve housing 12 and actuator 14 removed for clarity.

There are three main sub-assemblies within the valve housing 12: a first valve chamber region 18a which corresponds with the first valve housing part 12a and which forms an upper fluid chamber 20a which is fluidly communicable with the first fluid-flow port A; a second valve chamber region 18b which corresponds with the second valve housing part 12b and which forms three lower fluid chambers 20b, 20c, 20d which are respectively fluidly communicable with the second, third and fourth fluid-flow ports B, C, D; and a disc valve sub-assembly 22 which divides the first and second valve chamber regions 18a, 18b. The term region here is intended to refer to the volumes defined within the valve housing 12 when divided by the disc valve sub-assembly 22, irrespective of the total number of individual chambers formed within the said region.

The disc valve sub-assembly 22 comprises first and second discs 24, 26, preferably formed as rotatable ceramic discs, which can be rotatably aligned relative to one another so as to alter fluid-flow paths therethrough.

In the present embodiment, the first disc 24 is a movable disc, which is drivable via the actuator 14, whilst the second disc 26 is a static disc against which the first disc 24 moves.

The first disc 24 is formed having a non-rotationally symmetric aperture configuration. It has first and second primary apertures 28a, 28b, and a secondary aperture 30 Preferably, the primary apertures 28a, 28b are formed so as to extend radially inwardly into the first disc 24 with respect to the secondary aperture 30, which is preferably formed as an arcuate aperture through the first disc 24 at or adjacent to a perimeter thereof The disc valve sub-assembly 22 further comprises a flow-diverter cover 32 which is engagable with the first disc 24, and which is dimensioned to cover the first and second primary apertures 28a, 28b. The flow-diverter cover 32 is preferably formed as a domed element, therefore provided a substantially hemispherical inner surface which faces the first and second primary apertures 28a, 28b. A rim of the flow-diverter cover 32 is dimensioned to surround the first and second primary apertures 28a, 28b, and a sealing element, such as an 0-ring 34 is provided to create a fluid-tight seal between the first disc 24 and the flow-diverter cover 32. A circular or standard shaped 0-ring 34 has the advantage of limiting the torque transmitted to the seal when the first disc 24 is driven, whereas a non-standard seal might rupture under the torque applied, and cause leakage.

To connect to the first disc 24, the flow-diverter cover 32 may be provided with one or more engagement elements, such as the, preferably radially-extending, spigots 36 as shown, which may engage with corresponding receivers in the first disc 24 (not shown). It will be apparent, however, that the flow-diverter cover could be provided with receivers, with spigots from the first disc being engagable therewith, or an alternative fastening means could be utilised. Indeed, it may be possible to integrally for the flowdiverter cover with the first disc via an additive manufacturing process, for example.

The flow-diverter cover 32 preferably acts as a drive coupling for the first disc 24 with the actuator 14, having a shaft receiver 38 provided at a top of the cover which is engagable with a drive shaft 40 coupled to the actuator 14. A linear drive shaft 40 is provided in the present instance, and the shaft receiver 38 is coaxial with a centre of the first disc 24 once the flow-diverter cover 32 is attached. An eccentric drive shaft could alternatively be provided, however, where the flow-diverter cover 32 is eccentrically positioned on the first disc 24. The shaft receiver 38 preferably includes a keyed or shaped hole, such as a square or star-shaped hole, to prevent dephasing of the drive shaft 40 and flow-diverter cover 32 which could occur with a circular engagement surface.

The drive shaft 40 may include a support element which extends radially from the central axis, here formed as a plate 42, and this may allow a biasing means to be provided which holds the flow-diverter cover 32 in position. In the present embodiment, the biasing means comprises a spring 44, but it will be appreciated that alternative biasing means could be considered, for instance, rigid guide elements extending from the support element to contact the outer surface of the flow-diverter cover 32.

The second disc 26 is dimensioned so as to have main apertures 46 therethrough which respectively correspond with the second, third and fourth fluid chambers 20b, 20c, 20d that are fluidly communicable with the second, third and fourth fluid-flow ports B, C, D. In the configuration in which the fluidly communicable with the second, third and fourth fluid-flow ports B, C, D are symmetrically spaced around the circumference of the valve housing 12, it is logical for the main apertures 46 to be correspondingly rotationally symmetric. The second disc 26 thus has a three-fold rotational symmetry.

A specially-shaped sealing element 48 is provided which creates a seal between the second disc 26 and the second, third and fourth fluid chambers 20b, 20c, 20d.

No seal is required for the upper fluid chamber 20a, other than that between the flowdiverter cover 32 and first disc 24, since the entire upper fluid chamber 20a is formed as 5 a single chamber, and the only access routes therein are via the first fluid-flow port A and the secondary aperture 30.

Figures 3a and 3b show the flow diverter apparatus 10 in more detail. In particular, the cross-section of Figure 3b shows the division of the valve housing 12 into the first and second valve chamber regions. The valve housing 12 has been assembled showing the first and third fluid flow ports A, C in a co-planar condition, as indicated by line X-X, though it will be appreciated that the two part valve housing 12 is sufficiently adaptable to permit any rotational orientation of the first and second valve housing parts 12a, 12b, and the present relative orientation merely indicates one space-efficient arrangement.

As can be seen in Figure 3b, there may be provided a pinion or axle 48 which maintains the co-axiality of the first and second discs 24, 26 as well as the flow-diverter cover 32, and this is not drivably coupled to the drive shaft 40, since the second disc 26 is intended to be a static disc. The pinion or axle 48 could be integrally formed as part of the flow-diverter cover 32, and may freely rotate relative to the second disc 26.

In the configuration shown in Figures 3a and 3b, the third and fourth fluid-flow ports C, D are in fluid communication with one another, via a first fluid flow pathway which extends through the first and second primary apertures 28a, 28b in the first disc 24 and corresponding main apertures 46 of the second disc 26 and into the flow-diverter cover 32. The first and second fluid-flow ports A, B are in fluid communication with one another, via a second fluid flow pathway which extends through the other main aperture 46 in the second disc 46 and through the secondary aperture 30 of the first disc 24.

The fluid flow through the disc valve assembly 16 will now be described in more detail. Figure 4a shows the disc valve assembly, indicating the position of the disc valve assembly 22 in dashed lines, along with the first and second valve chamber regions 18a, 18b. Figures 4b(i) and 4b(ii) respectively show the first and second discs 24, 26, which in turn respectively indicative the relative positions of the first and second primary apertures 28a, 28b, the secondary aperture 30 of the first disc 24, and the main apertures 46 of the second disc 26. The position of the flow-diverter cover 32 is indicated on Figure 4b(i).

Figures 4c(i) and 4d(i) indicate the fluid flow in a first condition. The first and second primary apertures 28a, 28b are aligned to the main apertures 46 of the second disc 24 which correspond with the second and third fluid-flow ports B, C. It is noted that the shapes of the first and second primary apertures 28a, 28b correspond with an overlap of the flow-diverter cover 32 these main apertures 46, and this is illustrated by the overlap of the dashed lines in Figure 4d(i).

The first fluid-flow path therefore extends from the second fluid-flow port B, up through the main aperture 46 of the second disc 26 and into the first primary aperture 28a. The fluid can be reflected and diverted off the hemispherical or substantially hemispherical inner surface of the flow-diverter cover 32, and back through the second primary aperture 28b and othcr main aperture 46 of the second disc 26, to flow out of the third fluid-flow port C. In this configuration, the second and third fluid-flow ports B, C are therefore paired via the inner surface of the flow-diverter cover 32.

A second fluid-flow pathway is also present, which interconnects the first and fourth fluid-flow ports A, D. This second fluid-flow pathway is a more direct pathway, flowing from the first fluid-flow port A, through the secondary aperture 30 of the first disc 24, and through the main aperture 46 of the second disc 26 which corresponds with the fourth fluid-flow port D. The first and fourth fluid-flow ports A, D are therefore paired by the direct route along the second fluid flow pathway, that is, the flow is not reflected by the flow-diverter cover 32, as is the case for the first fluid flow pathway, and instead, the fluid along the second fluid flow pathway flows over the outside of the flow-diverter cover 32 within the upper fluid chamber 20a.

It will also be noted that the shape of the secondary aperture 30 may preferably also be defined by the overlap between the flow-diverter cover 32 and the relevant main aperture 46 of the second disc 26, though in this case the secondary aperture 30 is defined by the portion not covered by the flow-diverter cover 32, resulting in an arcuate aperture around the perimeter of the first disc 24.

Whilst fluid flow is shown in Figure 4c(i) as proceeding from the first fluid-flow port A as an inlet to the fourth fluid-flow port D as an outlet, and from the second fluid-flow port B as an inlet to the third fluid-flow port C as an outlet, it will be appreciated that these are indicative flow directions only, and that fluid flow can proceed in either direction according to user need.

When a change in the pairing between the fluid-flow ports A, B, C, D is required, then the actuator 14 can be used to rotate the first disc 24 with respect to the second disc 26. 10 A 120° anti-clockwise rotation of the first disc 24 and flow-diverter cover 32 is illustrated in Figures 4c(ii) and 4d(ii).

The first fluid-flow pathway is still defined by the position of the flow-diverter cover 32, however, the flow-diverter cover 32 is now positioned such that the first and second primary apertures 28a, 28b of the first disc 24 overlap the main apertures 46 of the second disc 26 associated with the second and fourth fluid-flow ports B, D, and therefore these two fluid flow ports are linked.

By extension, the secondary aperture 30 is positioned so as to overlap with the main aperture 46 associated with the third fluid-flow port C, thereby pairing it with the first fluid-flow port A. This arrangement of disc valve assembly 16 has the advantage of providing ready coupling between pairs of adjacent fluid-flow ports A, B, C, D, and which can be readily driven by a single actuator. This is a highly compact and effective way of diverting fluid to required sources. This is particularly significant for automotive contexts, particularly where complicated cooling fluid pathways are required, for instance, in hybrid electric vehicles. The valve allows for coolant fluid to be diverted as required to in-use battery systems.

An alternative embodiment of the flow diverter apparatus according to the present invention is shown in Figures 5a, 5b and 5c, and is indicated globally at 110. Identical or similar reference numerals to those used in relation to the first embodiment will be used for identical or similar components, and further detailed description is omitted for brevity.

The flow diverter apparatus 110 includes a valve housing 112, to which is mounted an actuator 14, which provides the driving force to the internal components of the disc 5 valve assembly.

Instead of the fluid-flow ports A, B, C, D being arranged in two planes, all four of the fluid-flow ports A, B, C, D of the present embodiment are co-planar, arranged in a rotationally symmetric spaced-apart configuration about the second valve housing part 112b. In this arrangement, the first valve housing part 112a includes no fluid-flow ports, and therefore it may be possible to reduce the height of the first valve housing part 112a accordingly.

The lack of a fluid-flow port on the first valve housing part 112a, and therefore no fluid-flow port in direct communication with the upper fluid chamber, has an effect on the flow through the apparatus. This difference is outlined below.

Figure 6a shows an equivalent diagram of the disc valve assembly 116 to that shown in Figure 4a, again, with the disc valve assembly 122 being shown in dashed lines. It is noted that the first valve chamber region 118a comprises one upper fluid chamber, whereas the second valve chamber region 118b comprises four lower fluid chambers, each one being associated with one of the fluid-flow ports A, B, C, D. The configuration of the first and second discs 124, 126 is shown in Figures 6b(i) and 6b(ii), and highlights the need for an alternative aperture arrangement. The first disc 124 includes first and second primary apertures 128a, 128b, which are again bounded beneath the flow-diverter cover 132, shown in dashed lines. However, two discrete secondary apertures 130a, 130b are provided, each being formed as a perimeter arcuate aperture outside of the bounding of the flow-diverter cover 132.

The corresponding main apertures 146 of the second disc 126 can be seen as four rotationally symmetric apertures, each being formed as a quarter-circle opening through the second disc 126. As with the first embodiment of the invention, the shapes of the primary and secondary apertures 128a, 128b, 130a, 130b may be defined by the overlap between the flow-diverter cover 132 and the main apertures 146, when in a correctly oriented state. A correctly-oriented state in this regard refers to an alignment between the apertures in which there is no fluid leakage into adjacent chambers, for example, were a secondary aperture 130a, 130b to overlap two main apertures 146 simultaneously.

Figure 6c(i) shows the fluid flow between the fluid-flow ports A, B, C, D when the first and second discs 124, 126 are aligned in a first configuration as shown in Figure 6d(i). The first fluid flow pathway extends from the first to the third fluid-flow ports A, C, via the first and second primary apertures 128a, 128b in the first disc 124. The second fluid flow pathway extends from the second to the fourth fluid-flow ports B, D, via the secondary apertures 130a, 130b.

A second configuration is shown in Figures 6c(ii) and 6d(ii), in which a 90° clockwise rotation of the first disc 124 has been effected. In this configuration, the first and second primary apertures 128a, 128b couple the first and fourth fluid-flow ports A, D to one another to form the first fluid flow pathway, and the second and third fluid-flow ports B, C arc coupled to one another via the secondary apertures 130a, 1306 to form the second fluid-flow pathway.

Continued rotation of the first disc 124 will cause linkage of the alternative adjacent fluid-flow port A, B, C, D combinations.

The difference in the fluid flow along the second fluid-flow pathway is highlighted in 20 Figures 7a, 7b, 8a, and 8b, showing the first configuration of the first and second discs 124, 126 as shown in Figures 6c(i) and 6d(i).

The reflection of the fluid flow along the first fluid-flow pathway is identical to that of the first embodiment; fluid is reflected back onto itself and is channelled between the first and third fluid-flow ports A, C. A similar flow route is taken on the second fluid-flow pathway, however. Since there is no fluid-flow port on the first valve chamber region 118a, the fluid flow is reflected back on itself in the negative space defined around the outer surface of the flow-diverter cover 132 inside the first valve chamber region 118a.

Figures 7a and 7b also better highlight the positioning of the flow-diverter cover 132 on the first disc 124. It is preferred that the flow-diverter cover 132 is eccentrically positioned on the first disc 124, and therefore the spigots 136 or similar engagement elements are offset relative to the centre of the first disc 124. On the other hand, the shaft receiver 138 is preferably centrally positioned on the first disc 124 to simplify drive shaft engagement.

Given the nature of the flow reflection in both fluid-flow pathways in this arrangement, it may be possible to provide a second flow-diverter cover which covers the secondary apertures 130a, 1306, therefore isolating the drive shaft from the fluid flow passing 10 therethrough. This may improve the reliability of the disc valve assembly.

Instead of a second flow-diverter cover, a single multi-chamber flow-diverter cover could be provided, which may allow a rotationally symmetric flow-diverter cover to be provided. This may allow the biasing means to apply a central force onto the outer surface of the flow-diverter cover, and could also simplify the assembly thereof Overall, the flow diverter apparatuses 10; 110 previously described can be used to provide a method of controlling the flow between adjacent fluid-flow ports A, B, C, D of the flow diverter apparatuses 10; 110, and the method can be summarised as follows: a first fluid-flow pathway is provided through the flow diverter apparatus 10; 110 and a second fluid-flow pathway through the flow diverter apparatus 10; 110 using a disc valve assembly 16; 116, wherein there is a flow-diverter cover 32; 132 positioned on the first fluid-flow pathway; a first configuration of the disc valve assembly 16; 116 is selected such that a first adjacent pair of fluid-flow ports is connected by the first fluid-flow pathway and a second adjacent pair of fluid-flow ports is connected by the second fluid-flow pathway; and a second configuration of the disc valve assembly 16; 116 is selected such that a third adjacent pair of fluid-flow ports is connected by the first fluid-flow pathway and a fourth adjacent pair of fluid-flow ports is connected by the second fluid flow pathway.

Whilst embodiments have thus far been described in terms of four-port arrangements, it will be appreciated that more complicated valve systems could be produced by altering 30 the configurations of the discs. The assembly could be upscaled so that any number of fluid-flow ports can be made, and connections made between any adjacent fluid-flow ports without difficulty by the use of a plurality of flow-diverter covers or split chambers. A flow-diverter cover with split chambers would, however, need a more complicated seal to be used to contact the first disc, and there is a greater chance of leakage.

Additionally, blanks in the discs could be provided so as to block flow from specific fluid-flow ports, and this may become important if an odd number of fluid-flow ports is provided as part of the disc valve assembly.

It is therefore possible to provide a disc valve assembly in which first and second different fluid flow pathways can be created, to join adjacent fluid-flow ports, by the provision of a disc which is associated with a flow-diverter cover. The fluid-flow pathways can then be selected by rotation of the disc, which is coupled to a single actuator. A compact flow controller can therefore be created in a cost-effective manner.

The words 'comprises/comprising' and the words 'having/including' when used herein 15 with reference to the present invention are used to specify the presence of stated features, integers, steps or components, but do not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

The embodiments described above are provided by way of examples only, and various other modifications will be apparent to persons skilled in the field without departing 25 from the scope of the invention as defined herein.

Claims (24)

1. Claims A disc valve assembly comprising: a valve housing having a plurality of fluid-flow ports; and a disc valve sub-assembly positioned to divide the valve housing into first and second valve chamber regions; the disc valve sub-assembly comprising: a first disc having first and second primary apertures and at least one secondary aperture therethrough; a second disc having at least three main apertures therethrough; and a flow-diverter cover engagable with the first disc to fluidly connect the first and second primary apertures to one another; wherein a relative rotational position of the first and second discs is adjustable to selectively form a first fluid-flow pathway bctwccn a first two of the plurality of fluid-flow ports which extends through two of the main apertures and the first and second primary apertures, via the flow-diverter cover, and a second fluid-flow pathway between a second two of the plurality of fluid-flow ports which extends through at least one other of the main apertures and the or each secondary aperture.
2. 2. A disc valve assembly as claimed in claim 1, wherein the flow-diverter cover is releasably engagable with the first disc.
3. 3. A disc valve assembly as claimed in claim 2, wherein the flow-diverter cover comprises at least one engagement member for engaging with the first disc.
4. 4. A disc valve assembly as claimed in claim 3, wherein the engagement member is provided as a spigot or receiver on the flow-diverter cover which is engagable with a corresponding spigot or receiver on the first disc.
5. 5. A disc valve assembly as claimed in any one of the preceding claims, wherein the first disc is a movable disc, and the second disc is a static disc.
6. 6. A disc valve assembly as claimed in claim 5, further comprising a drive shaft which is engagable with the flow-diverter cover to provide motive force to the first disc.
7. 7. A disc valve assembly as claimed in claim 6, wherein the flow-diverter cover is eccentrically positioned on the first disc.
8. 8. A disc valve assembly as claimed in claim 7, wherein the drive shaft is an eccentric drive shaft.
9. 9. A disc valve assembly as claimed in claim 6, wherein the flow-diverter cover is eccentrically positioned on the first disc, the drive shaft engaging with the flow-diverter cover along an axis of rotation of the movable disc.
10. 10. A disc valve assembly as claimed in any one of claims 6 to 9, wherein the flow-diverter cover includes a shaft receiver, the drive shaft being engagable with the shaft receiver.
11. 11. A disc valve assembly as claimed in any one of the preceding claims, further comprising biasing means for biasing the flow-diverter cover against the first disc.
12. 12. A disc valve assembly as claimed in claim 11 when dependent on any one of claims 5 to 9, wherein the drive shaft comprises a support element against which the biasing means is seatable to provide a biasing force to the flow-diverter cover.
13. 13. A disc valve assembly as claimed in any one of the preceding claims, wherein the valve housing comprises four said fluid-flow ports.
14. 14. A disc valve assembly as claimed in claim 13, wherein there is one upper said fluid-flow port which corresponds with the secondary aperture of the first disc, and three lower said fluid-flow ports, each of which corresponds with one of the three main 25 apertures of the second disc.
15. 15. A disc valve assembly as claimed in claim 13, wherein the four said fluid-flow ports are co-planar, each of the four said fluid-flow ports corresponding with one of four said main apertures of the second disc, and wherein there are two said secondary apertures in the first disc, the second fluid-flow path being diverted into and out of the first valve chamber region via the two secondary apertures.
16. 16. A disc valve assembly as claimed in any one of the preceding claims, wherein the first fluid-flow path and second fluid-flow path are selectably formable between any two adjacent pairs of fluid-flow ports of the disc valve assembly.
17. 17. A disc valve assembly as claimed in any one of the preceding claims, wherein each of the first and second primary apertures is formed as an overlapping section of the flow-diverter cover with a main aperture.
18. 18. A disc valve assembly as claimed in any one of the preceding claims, wherein the or each second aperture is formed as an arcuate aperture.
19. 19. A disc valve assembly as claimed in any one of the preceding claims, wherein the flow-diverter cover is formed as a domed element.
20. 20. A disc valve assembly as claimed in any one of the preceding claims, wherein the flow-diverter cover comprises a hemispherical or substantially hemispherical inner surface which faces the first and second primary apertures.
21. 21. A disc valve assembly as claimed in any one of the preceding claims, wherein a plurality of said flow-diverter covers is provided.
22. 22. A flow diverter apparatus comprising a disc valve assembly as claimed in any one of the preceding claims and an actuator for providing a driving force to adjust the relative rotational position of the first and second discs of the disc valve assembly.
23. 23. An automotive cooling system comprising a flow diverter apparatus as claimed in claim 22.
24. 24. A method of controlling the flow between adjacent fluid-flow ports of a flow diverter apparatus, the method comprising the steps of: a] providing a first fluid-flow pathway through the flow diverter apparatus and a second fluid-flow pathway through the flow diverter apparatus using a disc valve assembly, wherein there is a flow-diverter cover positioned on the first fluid-flow pathway; b] selecting a first configuration of the disc valve assembly such that a first adjacent pair of fluid-flow ports is connected by the first fluid-flow pathway and a second adjacent pair of fluid-flow ports is connected by the second fluid-flow pathway; and c] selecting a second configuration of the disc valve assembly such that a third adjacent pair of fluid-flow ports is connected by the first fluid-flow pathway and a fourth adjacent pair of fluid-flow ports is connected by the second fluid flow pathway.