GB2505911A

GB2505911A - Device to control water flow through a central heating system

Info

Publication number: GB2505911A
Application number: GB1216417.4A
Authority: GB
Inventors: Alan Rodney Henderson
Original assignee: IPOCAUST Ltd
Current assignee: IPOCAUST Ltd
Priority date: 2012-09-14
Filing date: 2012-09-14
Publication date: 2014-03-19
Anticipated expiration: 2032-09-14
Also published as: GB2505911B; GB201216417D0

Abstract

The device 301 is arranged to control a flow of water through a central heating system comprising a plurality of zones (1-4, figure 2). The device comprises a plurality of distribution ports 304A-D, which are preferably inlet ports receiving return water from one or more radiators located in each of the zones, and a shared port 305, which is preferably an outlet port connected to a return pipe leading to a boiler of the central heating system. Each distribution port corresponds to one of the plurality of zones. Flow of water through each of the distribution ports is controlled by the device so that flow is selectively prevented or permitted to any number of the plurality of zones. A cam 302 or double-cam (704,709, figure 7) can be used to open or close the distribution ports by rotating with respect to cam followers 306A-D provided on each of the distribution ports. The position of the double-cam can be monitored and thus controlled using micro-switches (710, figure 7) so that the double-cam is rotated to a desired position.

Description

Control Device

CROSS REFERENCE TO RELATED APPLICATIONS

This application represents the first application for a patent directed towards the invention and the subject matter.

a BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a device for controlling the flow of water through a central heating system, a central heating system including said device, and a method of controlling the flow of water through such a central heating system.

2. Description of the Related Art

Standard central heating systems have limited controls and can often include a single setting which switches the entire heating system on and off such that all areas of a property are heated at the same time. Zoned heating systems are known in the art as an improvement on this method by allowing users to control different areas of a property depending on user requirements.-Despite zoned heating systems providing improved heating and comfort combined with greater efficiency, they require large capital costs and complex control systems with complex wiring which need highly skilled tradespeople to fit. Current systems often utilise manifold valves with individual actuators in each zone which can also lead to increased cost and complexity of the system.

Thus, there remains a desire to improve the overall efficiency and viability of current zoned heating systems by addressing these problems.

BRIEF SUMMARY OF THE INVENTION

According to an aspect of the present invention, there is provided a device for controlling the flow of water through a central heating system, said central heating system comprising a plurality of zones, said device comprising: a plurality of distribution ports, each distribution port corresponding to one of said plurality of zones; and a shared port, whereby the flow of water is configured to flow between said plurality of distribution ports and said shared port; wherein flow through each of said plurality of distribution ports is restricted by said device such that flow can be prevented to any number of said plurality of zones.

According to a further aspect of the present invention, there is provided a central heating system comprising: a boiler; a plurality of zones; a device for controlling the flow of water through said central heating system, said device comprising: a plurality of distribution ports, each distribution port corresponding to one of said plurality of zones; and a shared port; whereby the flow of water is configured to flow between said plurality of distribution pods and said shared port; wherein flow through each of said plurality of distribution ports is restricted by said device such that flow can be prevented to any number of said plurality of zones.

According to a still further aspect of the present invention, there is provided a m!thod of controlling the flow of water through a central heating system, comprising the steps of: installing a device comprising a plurality of distribution ports and a shared port to enable the flow of water to flow between said plurality of distribution ports and said shared pod; connecting each of said distribution ports to a corresponding one of plurality of zones; restricting a flow through said plurality of distribution ports by means of said device; and preventing flow to any number of said plurality of zones.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a typical scenario in a building utilising a central heating system; Figure 2 shows a schematic diagram of a central heating system; Figure 3 shows a simplified single cam arrangement for a control device; Figure 4 shows an isolated view of the single cam of Figure 3; Figure 5 shows an isolated view of the cam follower of Figure 3; Figures GA and 6B show cross-sectional views of part of a control device; Figure 7 shows a cross-sectional view of a control device in accordance with the present invention; Figure 8 shows a perspective view of a control device in accordance with the present invention; Figures 9A, GB and 9C show the sixteen different configurations for a control device with tour distribution ports; Figure 10 shows a table indicating the sixteen configurations of the four-port control device; Figure 11 shows and electrical system of position control for a control device in accordance with the present invention; Figure 12 shows an isolated view of a double cam in accordance with an alternative aspect of the present invention; Figure 13 shows a cross-sectional view of a control device utilising the double cam of Figure 11; Figure 14 shows a cross-sectional view of a fully assembled control device utilising the double cam of Figure 11; Figure 15 shows a perspective view of the control device in accordance with the present invention; and Figure 16 shows a flow chart for controlling the position of the cam previously described.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

Figure 1 A typical scenario in a building utilising a central heating system is shown in Figure 1. Figure 1 shows a zone or room, indicated generally by the numeral 101 which includes a radiator 102 which is configured to emit heat to the surrounding area of room 101 thereby providing warmth to user 103 In this example embodiment, zone 101 is a single room comprising a single radiator 102. However, it is appreciated that a zone may comprise several rooms with either a single radiator or a plurality of radiators which are substantially similar to radiator 102 and which also emit heat to user 103. In one embodiment, zone 101 comprises a single room with a plurality of radiators for example.

Radiator 102 is connected to any conventional type central heating system which typically includes heat emitters, such as radiator 102, and a boiler, as indicated in the example shown in Figure 2.

Figure 2 A schematic diagram of a central heating system in accordance with that previously discussed in Figure 1, is shown in Figure 2. Central heating system 201 is an example of a zoned heating system and comprises a boiler 202 and a plurality of zones 203A, 203B, 203C, and 203D. Each zone 203 relates to a particular area, zone or room of a property or a building which requires heating. This would typically include a room such as room 101 as shown in Figure 1. In an example embodiment, 203A is a living room, 203B is a bedroom, 203C is a bathroom and 203D is a study area.

Each of the zones 203 include at least one heat emitter for providing warmth to the zone, such as radiator 102 or similar. Each one of the plurality of zones 203 receives water from a boiler 202 which is used to heat the zones to the temperature requested by a user. The water is then configured to flow back into the boiler 202 and circulates around the heating system as required and indicated by the arrows shown in Figure 2.

Central heating system 201 further comprises a control device 204 which directs the flow of water through the central heating system 201. Device 204 is configured as a junction to direct the flow from each zone in accordance with demand which is determined typically by the zone temperature and occupancy times to suit the user.

It is appreciated that while the central heating system 201 as shown in Figure 2 shows four separate zones 203, an alternative number of zones may be present in alternative central heating systems. For example, in a particular.

embodiment, central heating system 201 comprises a single zone which receives a flow of water from boiler and outputs a flow of water to the control device before returning the flow of water back to the boiler. The single zone includes a single radiator, however, it is appreciated that a plurality of radiators may also be present.

In an alternative embodiment, there are two zones which relate to the upstairs and downstairs of a building. A further embodiment has five separate zones. It is noted however, that the number of zones for use with control device 204 is not limited and control device 204 functions under the same principles irrespective of the number of zones or rooms in the central heating system.

In the illustrated embodiment of Figure 2, control device 204 is positioned in the return pipe of central heating system 201 and configured to control the water flow return to the boiler 202 from the individual zones. Control device 204 is also configured to remain closed to retain the water of the water flow in the individual zoned areas when the temperature of the water is above a predetermined temperature.

In an embodiment, the boiler 202 is a condensing boiler which utilises a system which extracts the latent heat of condensation to provide maximum efficiency. A condensing boiler of this type operates at an optimum efficiency when the temperature is below a predetermined temperature. Consequently, when the temperature rises above this predetermined temperature, flow is prevented through the control device. This type of operation of the control device is further described in the Applicant's co-pending application entitled Controlled Heating System.

Figure 3 Figure 3 shows a single cam arrangement for a control device 301 in accordance with the present invention. The cam arrangement shown comprises a single cam 302 positioned in a housing 303. Control device 301 comprises a plurality of distribution ports 304A, 304B, 304C and 304D and a shared port 305. Each of the distribution ports 304 correspond to one of a plurality of zones, such as the zones described previously in Figures 1 and 2.

Control device 301 as shown in Figure 3 corresponds to a central heating system which includes four separate zones and thus indicates four distribution ports 304, each distribution port corresponding to one of the plurality of zones. For example, it can be seen that distribution port 304A could correspond to zone 203A shown in Figure 2 and, similarly, zone 203B could correspond to distribution port 304B and so on.

Shared port 305 is configured to receive a flow of water from each of the distribution ports 304 such that the flow of water in a central heating system flows between the plurality of distribution ports and the shared port 305. Control device 301 is configured to restrict flow through each of the distribution ports 304 such that flow can be prevented to any number of these zones. Specifically, control device 301 is configured such that a flow through distribution port 304 can be either permitted or prevented, irrespective of whether flow is flowing through any of the other distribution ports 304B, 304C or 304D. In contrast, shared port 305 remains open to permit a flow whenever one enters the control device.

In the embodiment shown, each of the distribution ports are ted water from a particular zone in the central heating system such that the water flows from these ports to the shared port 305 and thus returns to the boiler. In an alternative embodiment, control device 301 may be positioned in the central heating system such that water flows in via shared port 305 and out via the distribution ports 304.

The flow through each of the distribution ports 304 is restricted by means of the cam 302 which operates a plurality of cam followers, indicated at 306A, 306B, 306C and 306D. The cam followers 506 are each configured to activate a valve positioned in each of the distribution ports.

Cam 302 is, in this embodiment, a single cam comprising a plurality of high profile sections, such as high profile section 307 and a plurality of low profile sections such as low profile section 308. The high profile sections and low profile sections are configured to open and close the distribution ports 304 such that, as the cam 302 rotates, the high profile sections push the cam followers 306 away from the centre of cam 302 and the low profile sections

B

allow the cam followers 306 to retract towards the centre of cam 302. This is shown in further detail in Figures 6A and 6B and subsequent Figures 9A, 9B and 9C.

In this illustrated embodiment, the number of distribution ports is four which corresponds to a four zone central heating system. In an alternative embodiment, the number of distribution ports is three which corresponds to a three zone central heating system. In a further embodiment, the number of distribution ports is two, thus corresponding to a two zone central heating system, such as the example referred to previously of a zoned heating system whereby the zones correspond to the upstairs and the downstairs of a building.

In further embodiments, the number of distribution ports is increased with increase of zones required.

The distribution pods as shown can be considered as being arranged in two pairs. A first pair comprising distribution port 304A and distribution port 304C are arranged 135°C apart. Similarly, a second pair comprising distribution port 304B and distribution port 3040 are also arranged 135°C apart. From a central point indicated at 509 and moving in an anticlockwise direction around the cam, the distribution ports are arranged around cam 302 at intervals of 22.5°C, 112.5°C, 247.5°C, and 337.5°C. The nature of this geometric arrangement allows for the distribution ports to be arranged in the above embodiments as shown further in Figures 13 to 15.

Figure 4 Figure 4 shows an isolated view of cam 402 for use in control device 301 as shown in Figure 3. As previously stated, the cam is a single cam which comprises a plurality of high profile sections such as high profile sections 401, 402 and 403, and a plurality of low profile sections such as low profile sections 404, 405 and 406. The plurality of high profile sections and plurality of low profile sections are configured to open and close the distribution ports shown in Figure 3 respectively.

The single cam shown in Figure 4 further comprises a cam shaft 407 which in operation, is driven by an electric motor to enable the cam to rotate within control device 301.

Cam 302 further comprises a plurality of holes, such as hole 408, which is maintained through the depth of the cam to maintain a flow path between the plurality of distribution ports and the shared port.

Figure 5 Figure 5 shows an isolated view of cam follower 306. The view also includes an 0' ring 501 and a resilient member 502. Resilient member 502 in this example is a spring. When positioned in control device 301 the spring is biased to maintain each of the distribution ports in a closed position. The 0' ring 501 allows for a seal to be maintained in each of the distribution ports when each of the distribution ports are closed.

Figures 6A and 66 Figures 6A and 68 show cross sectional views of part of a control device 601 showing a distribution pod 602 in a closed position (Figure 6A) and an open position (Figure 6B). Control device 601 comprises a housing 603 and a cam 604, the cam comprising a plurality of high profile sections, for example, high profile section 605, and a plurality of low profile sectionS, such as low profile section 606.

It is appreciated that the control device 601 as shown in Figures 6A and Figure 68 is substantially similar to the embodiments shown in Figures 3, 4 and 5. Thus, control device 601 comprises distribution port 602 (which may correspond to any one of the distribution ports 304 as previously discussed), which includes a cam follower 607 which is substantially similar to cam follower 306 as shown previously in Figure 5. Cam follower 607 is configured to be biased in the closed position of Figure GA by means of a resilient member 608.

In this illustrated embodiment, resilient member 608 is a spring.

Distribution port 602 includes an angled face 609 on to which cam follower 607 abuts when in the closed position of Figure GA. The cam 604 is configured to rotate from the closed position shown in Figure 6A to the open position shown in Figure 6B. In Figure 6A cam follower 607 is in contact with low profile section 606, and, upon rotation of the cam, cam follower 607 comes in contact with high profile section 605. As high profile section 605 contacts cam follower 607, cam follower 607 moves away from edge 609 and pushes against spring 608 thereby releasing the seal created by 0' ring 610 and thus IS opening the distribution port 602.

The cam 604 can rotate such that low profile section 606 is able to contact cam follower 607 to close the distribution port as required. Similarly, upon rotation, high profile section 605 is able to contact cam follower 607 at required intervals to enable the distribution port to open. It is appreciated that cam follower 607 is also able to be opened and closed by other high and low profile sections of the cam not shown in this Figure as required.

Figure 7 Figure 7 shows a cross sectional view of a control device 701 which is substantially similar to the control device 301 as shown in Figure 3 and which may be used in the system shown in Figure 2. Device 701 shows a distribution port 702 which corresponds to a particular zone in the central heating system.

Device 701 further comprises a shared port 703 to which flow between distribution port 702 and shared port 703 can flow between. Device 701 further comprises a cam 704 which operates cam follower 705 which in turn activates a valve in the distribution port. Cam 704 includes a cam shaft 706 which connects to a drive wheel 707. Drive wheel 707 is driven by an actuator motor 708. Actuator motor 708 actuates the drive wheel 707 which rotates the cam 704 by means of the cam shaft 706.

An external cam 709 -substantially similar in profile to cam 704 -operates micro-switches 710 whenever the corresponding distribution port 702 is open.

In an embodiment, electric motor 708 is a synchronous motor. In a particular embodiment, the motor and gear of the synchronous motor has a rate of five revolutions per minute but is geared down further to increase the torque by drive wheel 707.

Figure8 Figure 8 shows the control device 701 in a perspective view. Control device 701 includes distribution pods 702A, 702B, 702C and 702D. Control device 701 further includes a shared port 703 and a cam 709. The drive wheel 707 can be seen positioned above cam 709 which is controlled by a plurality of micro-switches 710 which are configured to enable the distribution ports 702 to open and close. Each of the distribution ports 702 has a respective micro-switch 710.

Figures 9A, 9B and 9C The control device as previously discussed in Figures 3 to 8 is configured such that any one of the distribution ports can be opened or closed irrespective of the open or closed position of any of the other distribution ports.

The shared port is configured to always remain open. Figures 9A, 96 and 9C show the sixteen different configurations available for the four distribution port control device shown previously in Figure 3.

With specific reference to Figure 9A, 900 shows the control device 301 in which all four of the distribution pods are closed by means of the cam 302.

As shown, the shared port 305 remains open. As the cam rotates as described previously, the cam moves into Position 1 indicated at 901. In this embodiment, distribution ports 304C and 304D are open while distribution ports 304A and 3048 remain closed.

As the cam rotates further in an anti-clockwise direction, distribution port 3048 opens with the remaining distribution pods shown in the same position as that seen at Position 1.This is shown at Position 2 indicated at 902. At 903, the cam has rotated further into Position 3, in which distribution port 304B is the only one of the four distribution ports which is closed. Similarly, 904 shows the cam following rotation into a Position 4 whereby distribution ports 304A and 304C are open and distribution ports 304B and 3040 are closed.

At Position 5, indicated at 905, the cam has rotated such that distributions ports 304A and 3040 are open and distributions ports 304B and 304C are closed.

With reference now to Figure GB, the next six possible configurations of the cam are shown. At 906, corresponding to a cam position 6, distribution port 3040 is open with the remaining distribution ports in a closed position. At Position 7, indicated at 907, distribution port 304C remains closed while the other three distribution ports are all open.

Following further rotation anti-clockwise of the oam 502, the cam moves into Position 8, indicated at 908, Position 9 indicated at 909, Position 10 indicated at 910, and Position 11 indicated at 911. At Position 8 each of the distribution ports are shown as being open, and, as the cam rotates further at Position 9, distribution ports 304A and 304B are open with 304C and 3040 being closed.

s At Position 10, only distribution port 304A remains open and, in contrast, at Position 11 only distribution port 304B is open.

The final four configurations relating to cam position are shown in Figure 9C in which Position 12 is indicated generally by the numeral 912, Position 13 is indicated generally by the numeral 913, Position 14 is indicated generally by the numeral 914 and Position 15 is indicated generally by the numeral 915.

At 912, that is when the cam is at Position 12, distribution ports 504A and 504C are closed with distribution ports 5048 and 504D remaining in the open position.

i5 Following further rotation, at Position 13, distribution ports 504A and 504D are closed and distribution ports 504B and 504C are open.

With reference to Position 14, indicated at 914, the distribution pods are open with the exception of distribution port 3040 which remains closed.

Similarly, at Position 15, indicated at 915, the distribution ports remain closed with the exception of distribution port 304C which is open.

Figure 10 The positions shown in Figures 9A, 9B and 9C have been tabulated in Figure 10 which shows each of the cam positions indicated at numeral 1001 and the corresponding positions of each of the distribution ports depending on the position of the cam. The hatched areas in the table indicate the cam profile depending on its position. For reference, the hatched areas correspond to high profile sections of the cam and the areas which do not show hatching correspond to the low profile sections of the cam.

For example, column 1002 shows the respective configuration of distribution port 304A for each given cam position. Thus, it can be seen that when the cam position is at Position 4 (as shown in Figure 9A by the numeral 904) the distribution port is open as shown in the table at 1003. Similarly, the distribution port 304B at this cam position is shown as being closed, indicated in the table at 1004.

With reference to the table shown at 1005, the open and closed positions are given values of either 1' or 0' respectively which are used to populate the look up table 1005. Thus, when a distribution port is closed, the value is 0' and when the distribution pod is open, the value is 1'. Referring again to Position 4 of the cam, it can be seen at 1006 that the value is given as "1, 0, 1, 0". This value is then processed as an input signal which can be processed by the electrical system described in following Figure 11.

Figure 11 Figure 11 details an electrical system of position control for the control device described in the proceeding Figures. The open or closed positions of the distribution ports are controlled by four switches indicated at IIOIA, IIOIB, IIOIC and 11010. The switches are coincident with the four distribution ports shown the preceding Figures and are actuated by a corresponding cam.

The electrical system further comprises a series of switches 1102A, 1102B, 1102C and 1102D, which correspond to a user input. Each of the user inputs are determined as either having the heating system in a zone or room as off or on. In this illustrated example, if the user does not wish for the heating in a particular zone to be on then the input switch positions itself against the zero position (indicated as O) In contrast, if a user requires the heating in a particular zone or room to be on, then the input switch will move to position one (indicated as "1), thus, opening the respective distribution port to allow water to flow through the system and heat the zone.

For any combination of user inputs there is only one corresponding position where power to the motor 1104 is switched off. This particular position is configured to open or close the distribution ports as required, and as previously shown in Figure 9.

The electric system is powered by an electric power source indicated at 1103 which provides the necessary electrical input to a motor 1104, which, in turn operates to position the cam in the correct orientation to allow the distribution ports to open or close as required.

In this illustrated embodiment micro-switches are used to signal shaft position. However, in an alternative embodiment, electronic position sensors are used to signal shaft position in place of the micro-switches.

Figure 12 Figure 12 shows an isolated view of a double cam 1201, suitable for use in an alternative embodiment of the control device discussed previously. In this particular embodiment, cam 1201 is a double cam which, as with the single cam previously described, comprises a plurality of high profile sections, such as high profile section 1202 and a plurality of low profile sections such as low profile section 1203. The plurality of high profile sections and plurality of low profile sections are configured to open and close the distribution ports of the control device respectively.

The double cam shown in Figure 12 further comprises a cam shaft 1204 which is driven by an electric motor to enable the cam to rotate within a suitable control device.

Cam 1201 further comprises a plurality of holes, such as hole 1205, which is maintained through the depth of the cam to maintain a flow path between the plurality of distribution ports and the shared port of the control device.

Figure 13 Figure 13 shows cam 1201 positioned in a control device 1301 comprising a housing 1302. The double cam 1201 is positioned within housing 1302. Housing 1502 defines a plurality of distribution ports 1303 which are positioned in an in-line configuration. Each of the distribution ports 1303 include a cam follower 1304 such that cam 1201 is controlled by the plurality of cam followers 1304 positioned in each of the plurality of distribution ports.

Control device 1301 further comprises a shared port 1305 through which water may flow.

By utilising the double cam as shown in Figure 12 as opposed to the single cam as shown in Figure 4 the distribution ports 1303 can be rotated from the positions shown in Figure 3. For example, in Figure 3 distribution ports 304A and 304C can be considered a pair which can be rotated such that the configuration as shown in Figure 13 whereby the distribution ports 1303A and 1303B are positioned in close proximity can be achieved. This is because the shape of the initial single cam has been rotated such that each of the distribution ports can open and close by the same mechanism as described previously however, the distribution ports are now aligned such that the control device 1301 is easier to manufacture and easier to fit in a central heating system.

Figure 14 A cross-sectional view of the fully assembled control device 1401 as seen previously in Figure 14 is shown in Figure 14. Control device 1301 is suitable for use in the central heating system as shown in Figure 2 and utilises the double cam 1201 to enable an efficiently packaged control device.

Control device 1301 shows distribution ports 1303B and 1303C* and cam followers 1304B and 1304C positioned therein. Cam shaft 1204 can also be seen which is configured to rotate cam 1201 which in turn, operates cam followers 1304 which activates a valve in the distribution ports enabling them to open or close. Cam shaft 1204 connects to a drive wheel 1305. Drive wheel 1305 is driven by an actuator motor 1306. Thus1 actuator motor 1306 actuates the drive wheel 1305 to rotate the cam 1201 by means of cam shaft 1204.

In an embodiment, electric motor 1506 is a synchronous motor. In a particular embodiment the motor and gear of the synchronous motor has a rate of five revolutions per minute but is geared down to increase the torque.

The synchronous motor includes a motor gear with an encoder pattern which enables the motor to synchronise from a zero point, as will be described in Figure 16. For each rotation, the gear synchronises with the motor and calculates the number of cycles. The calculation can then be used to set the opening and closing positions of the distribution ports.

In an alternative embodiment, electric motor 1306 is a stepper motor, which is more instantaneous than the synchronous motor. This system further includes software which indicates which of the distribution ports are selected and which are open at a given point.

Figure 15 The control device 1301 is shown further in Figure 15. Control device 1301 includes housing 1302 including distribution ports 1303 and shared port 1501. Control device 1301 also includes a cover 1502 which is easily removable for maintenance but that protects the inner workings while in use and filled in a central heating system.

Control device 1301 is suitable for filling in the central heating system shown in Figure 2 and is configured for a four zone heating system as indicated by the four distribution ports. In alternative embodiments, it is appreciated that alternative control devices which operate under the same principles of the present invention may be used which have a reduced number of distribution ports or an increased number of distribution ports. Thus while the description focuses on the four port system, two port, three port, five port and other configurations may also be used operating under the same principles.

Furthermore, in an example embodiment, a quad cam system is used.

is This system includes four distribution ports with four single cams. Each of the four cams is then used to operate the opening and closing of each port. This embodiment enables variations on the packaging of the control device for different systems. For example, the distribution pods can be packaged such that each distribution port is positioned in substantially the same plane on top of each other.

In a further embodiment, the four port control device is arranged to form a cruciform such that each distribution pod is positioned at substantially 900 to its adjacent distribution ports. In this embodiment, with reference to the distribution ports as shown in Figure 3, distribution port 304A and distribution port 304B are rotated such that distribution port 3048 is in line with distribution port 304D. Similarly, distribution port 304A is in line with distribution port 304C.

Again, this indicates the flexibility of the invention so that it can be used in different heating systems.

Figure 16 Figure 16 shows a flow chart 1601 for controlling the position of the aforesaid described cam by means of a single sensor electronic system. This embodiment describes a means of positioning the cam shaft by using only one sensor which corresponds in this case to a zero position. The cam shaft as described in the embodiments of Figure 7 and Figure 14 is configured to rotate in one direction only. This application applies whether a stepper motor or a synchronous motor is being used.

With reference to flow chart 1601, at step 1602 a question is asked to determine if the cam is at a zero position, as indicated previously in Figures 9 and 10, and in which all the distribution ports are closed, If the cam is not at the zero position, the position motor runs and the cycle continues until the question is answered in the affirmative. When the question is answered in the affirmative, the position is logged and a question is asked at 1603 as to whether the input position from a user (indicated at 1604) is coincident with the logged position. In the event that the positions are coincident, a question is asked at 1605 to confirm whether the position is set at zero. If this question is answered in the negative, the boiler is switched on at step 1606. Thus, a flow is then enabled from the distribution ports to the shared port to enable the requested zones to be heated.

If the question asked at 1603 is answered in the negative, (meaning the input and logged positions are not coincident) then a question is asked at step 1607 to determine whether the required input can be achieved before the zero position is reached. If the question is answered in the affirmative, at step 1608 the position motor runs for a calculated runtime which is dependent on the required position of the cam and the ports required to be open. Once the motor has run for the calculated period, the position is logged.

If the answer at step 1607 is negative, however, the motor is configured to run to a point at which the valve is at the zero position. This enables the control procedure to rerun such that the motor runtime can be calculated to achieve the desired cam position.

When the input from a user is changed (step 1604), the cycle reinitiates and repeats the procedure to enable the respective distribution ports to be opened and closed as required.

The system as described herein is suitable for use in central heating systems, in particular zoned heating systems as described. However, the application and positioning of the control device is also suitable for use in under floor heating systems which would advantageously reduce the requirement for mixing valves to be used which would thereby improve the Is heating up period of the system. The system is also suitable for use in heating systems which utilise solar panels.

Claims

Claims What we claim is: 1. A device for controlling the flow of water through a central heating system, said central heating system comprising a plurality of zones, said device comprising: a plurality of distribution ports, each distribution port corresponding to one of said plurality of zones; and a shared port, whereby the flow of water is configured to flow between said plurality of distribution ports and said shared port; wherein flow through each of said plurality of distribution ports is restricted by said device such that flow can be prevented to any number of said plurality of zones.
2. A device for controlling the flow of water through a central heating system in accordance with claim 1, wherein flow through each of said plurality of distribution ports is restricted by said device such that flow to all of said plurality of zones can be prevented.
3. A device for controlling the flow of water through a central heating system in accordance with claim 1, wherein said device further comprises a cam and the flow through each of said plurality of distribution ports is restricted by means of said cam which operates a plurality of cam followers each configured to activate a plurality of valves in each of said plurality of distribution ports.
4. A device for controlling the flow of water through a central heating system in accordance with claim 3, wherein said cam is a single cam comprising a plurality of high profile sections and a plurahty of low profile sections configured to open and close said distribution ports.
5. A device for controlling the flow of water through a central s heating system in accordance with claim 3, wherein said cam is a double cam comprising a plurality of high profile sections and a plurality of low profile sections configured to open and close said distribution ports.
6. A device for controlling the flow of water through a central heating system in accordance with claim 3, wherein said cam is controlled by a plurality of cam followers positioned in each of said plurality of distribution ports.
7. A device for controlling the flow of water through a central heating system in accordance with claim 3, wherein said cam further comprises a cam shaft driven by an electric motor.
8. A device for controlling the flow of water through a central heating system in accordance with claim 1, wherein the opening and closing of said distribution ports are controlled by micro switches operated by a cam.
9. A device for controlling the flow of water through a central heating system in accordance with claim 1 wherein the number of said plurality of distribution ports is four.
10. A device for controlling the flow of water through a central heating system in accordance with claim 1, wherein the number of said plurality of distribution ports is three.
11. A device for controlling the flow of water through a central heating system in accordance with claim 1 wherein the number of said plurality of distribution ports is two.
12. A central heating system comprising: a boiler; a plurality of zones; a device for controlling the flow of water through said central heating system, said device comprising: a plurality of distribution ports, each distribution port corresponding to one of said plurality of zones; and a shared port; whereby the flow of water is configured to flow between said plurality of distribution ports and said shared port; wherein flow through each of said plurality of distribution ports is restricted by said device such that flow can be prevented to any number of said plurality of zones.
13. A central heating system in accordance with claim 12, wherein flow through each of said plurality of distribution ports is restricted by said device such that flow to all of said plurality of zones can be prevented.
14. A central heating system in accordance with claim 12, wherein said device further comprises a cam and the flow through each of said plurality of distribution ports is restricted by means of said cam which operates a plurality of cam followers each configured to activate a plurality of valves in each of said plurality of distribution ports.
15. A central heating system in accordance with claim 14, wherein said cam is a single cam comprising a plurality of high profile sections and a plurality of low profile sections configured to open and close said distribution ports.
16. A central heating system in accordance with claim 14, wherein said cam is a double cam comprising a plurality of high profile sections and a plurality of low profile sections configured to open and close said distribution ports.
17. A method of controlling the flow of water through a central heating system, comprising the steps of: installing a device comprising a plurality of distribution ports and a shared port to enable the flow of water to flow between said plurlity of distribution ports and said shared port; connecting each of said distribution pods to a corresponding one of plurality of zones; restricting a flow through said plurality of distribution pods by means of said device; and preventing flow to any number of said plurality of zones.
18. A method of controlling the flow of water through a central heating system in accordance with claim 17, wherein said flow to all of said plurality of zones is prevented when the water temperature of said flow is above a predetermined value.
19. A method of controlling the flow of water through a central heating system in accordance with claim 17, wherein said flow through said plurality of distribution ports is controlled by means of a cam which operates a plurality of cam followers each configured to activate a plurality of valves in each of said plurality of distribution ports.
20. A device for controlling the flow of water through a central heating system as described herein with reference to the accompanying Figures.
21. A central heating system as described herein with reference to the accompanying Figures.
22. A method of controlling the flow of water through a central heating system as described herein with reference to the accompanying Figures.Amendments to the claims have been filed as follows 26 -Claims What we claim is: 1. A device specifically adapted for controlling a flow of water through a central heating system, said central heating system comprising a plurality of zones, said device comprising: a plurality of distribution ports, each distribution port corresponding to one of said plurality of zones; and a shared port, whereby the flow of water flows between said plurality of distribution ports and said shared port; wherein io said device further comprises a cam and the flow through each of said plurality of distribution ports is restricted by means of said cam which operates a plurality of cam followers each configured to activate a plurality of valves in each of said plurality of distribution ports, and wherein flow through each of said plurality of distribution pods is restricted by is said cam such that flow is prevented to any number of said plurality of zones.2. A device for controlling the flow of water through a central heating system in accordance with claim 1, wherein flow through each of said plurality of distribution pods is restricted by said cam such that Ilow to all of said plurality of zones can be prevented.* *: 3. A device for controlling the flow of water through a central * * heating system in accordance with claim 1, wherein said cam is a single cam comprising a plurality of high profile sections and a plurality of low profile sections configured to open and close said distribution pods.4. A device for controlling the flow of water through a central heating system in accordance with claim 1 wherein said cam is a double cam comprising a plurality of high profile sections and a plurality of low profile sections configured to open and close said distribution ports.5. A device for controlling the flow of water through a central heating system in accordance with claim 1, wherein said cam is controlled by a plurality of cam followers positioned in each of said plurality of distribution ports.6. A device for controlling the flow of water through a central heating system in accordance with claim 1, wherein said cam further comprises a cam shaft driven by an electric motor.7. A device for controlling the flow of water through a central heating system in accordance with claim 1, wherein the opening and closing of said distribution ports are controlled by micro switches operated by a cam.8. A device for controlling the flow of water through a central heating system in accordance with claim 1 wherein the number of said plurality of distribution ports is four.* 9. A device for controlling the flow of water through a central * heating system in accordance with claim 1, wherein the number of said L: : plurality of distribution ports is three.10. A device for controlling the flow of water through a central heating system in accordance with claim 1, wherein the number of said plurality of distribution ports is two.11. A device for controlling the flow of water through a central heating system in accordance with claim I1 wherein said device is positioned in a return pipe of the central heating system.12. A device for controlling the flow of water through a central heating system in accordance with claim 11, wherein said device is configured to retain the water of the water flow in said plurality of zones when water temperature is above a predetermined temperature.13. A central heating system comprising: a boiler; a plurality of zones; a device specifically adapted for controlling a flow of water through said central heating system, said device comprising: a plurality of distribution ports, each distribution port corresponding to one of said plurality of zones; and a shared port; whereby the flow of water flows between said plurality of distribution ports and said shared port; wherein said device further comprises a cam and the flow through each of said plurality of distribution ports is restricted by means of said cam which operates * a plurality of cam followers each configured to activate a plurality of valves in * each of said plurality of distribution ports, and wherein flow throUgh each of said plurality of distribution ports is restricted by said cam such that flow is prevented to any number of said plurality of zones. fl... e14. A central heating system in accordance with claim 13, wherein flow through each of said plurality of distribution ports is restricted by said cam such that flow to all of said plurality of zones can be prevented.15. A central heating system in accordance with claim 13, wherein said cam is a single cam comprising a plurality of high profile sections and a plurality of low profile sections configured to open and close said distribution ports.16. A central heating system in accordance with claim 13, wherein said cam is a double cam comprising a plurality of high profile sections and a plurality of low profile sections configured to open and close said distribution ports.17. A method of controlling a flow of water through a cehtral heating is system1 comprising the steps of: installing a device comprising a plurality of distribution ports and a shared port to enable the flow of water to flow between said plurality of distribution ports and said shared port; connecting each of said distribution ports to a corresponding one of plurality of zones; restricting a flow through said plurality of distribution ports by means of * said device; and * St*..* preventing flow to any number of said plurality of zones, wherein said flow through said plurality of distribution ports is controlled by means of a cam which operates a plurality of cam followers each configured to activate a plurality of valves in each of said plurality of distribution ports. * * *18. A method of controlling the flow of water through a central heating system in accordance with claim 17, wherein said flow to all of said plurality of zones is prevented when the water temperature of said flow is above a predetermined value.19. A device for controlling the flow of water through a central heating system as described herein with reference to the accompanying Figures.20. A central heating system as described herein with reference to the accompanying Figures.21. A method of controlling the flow of water through a central heating system as described herein with reference to the accompanying Figures. S. S. *. SSS..... * C * 55 * . S I.. *S*5!555 * S p *5