FLUID LEVEL SENSING ASSEMBLY FOR MOTORISED VALVE

Abstract

A fluid level sensor assembly includes a first pipe component defining a flow path for the fluid and configured to be attached to a valve to control flow of the fluid from the first pipe component, and a fluid level sensor arranged in or on the first pipe component to detect a level of fluid in the first pipe component and to generate a command signal for operation of the valve according to the level detected. The assembly also includes an insert fitted to an end of the first pipe component and extending axially from the end to be fitted to an inlet of the valve, in use, wherein the insert is configured to secure the first pipe component against rotation relative to the valve inlet when the insert is fitted to the inlet.

Claims

1. A fluid level sensor assembly comprising: a first pipe component defining a flow path for the fluid and configured to be attached to a valve to control flow of the fluid from the first pipe component; a fluid level sensor arranged in or on the first pipe component to detect a level of fluid in the first pipe component and to generate a command signal for operation of the valve according to the level detected, an insert fitted to an end of the first pipe component and extending axially from the end to be fitted to an inlet of the valve, in use, wherein the insert is configured to secure the first pipe component against rotation relative to the valve inlet when the insert is fitted to the inlet.

2. The assembly of claim 1, wherein the first pipe component is a wye fitting defining a first branch that defines the fluid path and a second branch in which the sensor is located.

3. The assembly of claim 1, further comprising a clamp to fit around the first pipe component and the valve inlet when they are connected.

4. The assembly of claim 3, wherein the wye-fitting is provided with a nozzle to direct fluid from an inlet end to the branch in which the sensor is located, the nozzle having a first opening at the inlet end and a second, smaller opening at an outlet end directed to the sensor.

5. The assembly of claim 2, wherein the wye-fitting is provided with a nozzle to direct fluid from an inlet end to the branch in which the sensor is located, the nozzle having a first opening at the inlet end and a second, smaller opening at an outlet end directed to the sensor.

6. The assembly of any of claim 1, wherein the insert comprises locking features to provide an anti-rotation fit between the outlet end and the valve inlet.

7. A fluid level sensor assembly comprising: a wye fitting having a main branch defining a fluid path for a fluid to flow from an inlet end to an outlet end arranged to be connected to an inlet of a valve, and a second branch opening from the main branch at a position intermediate the inlet end and the outlet end; a level sensor is located in the second branch to detect a level of fluid in the second branch and to generate a command signal for operation of the valve according to the level detected; and a nozzle defining a channel outside the main branch, the channel having a first opening the main branch, at a position intermediate the inlet end and the second branch, and a second opening into the second branch, the second opening being smaller than the first opening.

8. The assembly of claim 7, further comprising an insert fitted to the outlet end of the wye fitting and extending axially from the end to be fitted to an inlet of a valve, in use, wherein the insert is configured to secure the wye fitting against rotation relative to the valve inlet when the insert is fitted to the valve inlet.

9. The assembly of claim 8, wherein the insert comprises locking features to provide an anti-rotation fit between the outlet end and the valve inlet.

10. The assembly of claim 7, wherein the locking features comprise teeth.

11. The assembly of claim 7, wherein the locking features comprises latches configured to latch into corresponding openings formed in a receiving part.

12. The assembly of claim 1, wherein the insert comprises a polymer.

13. The assembly of claim 7, wherein the insert comprises a polymer.

14. A fluid management system comprising: a valve; and an assembly as claimed in claim 1.

15. The system of claim 14, further comprising a fluid pipe arranged for connection with the valve via the assembly.

16. A fluid management system comprising: a valve; and an assembly as claimed in claim 7.

17. The system of claim 16, further comprising a fluid pipe arranged for connection with the valve via the assembly.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG. 1 shows a valve and water level sensor assembly according to the present disclosure.

[0016] FIG. 2 is an exploded view of the assembly of FIG. 1.

[0017] FIG. 3a-3e show the water flow in an assembly such as that shown in FIG. 1.

[0018] FIG. 4 is a cross-section of the assembly of FIGS. 1 and 2.

[0019] FIG. 5 is an exploded cross-section view of the assembly of FIG. 4.

[0020] FIG. 6 is a cross section view of a further embodiment of an assembly according to the disclosure.

[0021] FIGS. 7a-7e show the water flow in an assembly such as that shown in FIG. 6.

[0022] FIG. 8 is a detailed view of a connection insert according to one example.

[0023] FIG. 9 is a detailed view of a connection insert according to another example.

[0024] FIG. 10 is a perspective view of a detail of an assembly according to the disclosure.

DETAILED DESCRIPTION

[0025] Referring first to FIGS. 1 and 2, the assembly of the disclosure will be described, by way of example only, for a system comprising a valve 1 connected between a first part of a water system e.g. a reservoir 10 and another part of the water system e.g. waste pipe 20. Depending on the type of water system, the valve 1 may be a normally open valve or a normally closed valve. Opening and closing of the valve 1 is controlled based on a water level in the system detected by a water level sensor 2. For a normally open valve, the valve motor is commanded to close the valve if the sensor detects a water level above a given threshold. For a normally closed valve, the valve motor is commanded to open the valve if the sensor detect a water level above a give threshold. For the following description, a normally closed valve will be used, by way of example only. The same principles will, however, apply to a normally open valve.

[0026] As seen in the drawings, the level sensor 2 is mounted in a wye fitting 30 attached between the valve inlet 11 and the waste pipe 20. One branch 31 of the wye fitting 30 is in line with the waste pipe 20. The other branch 32 of the wye fitting extends from the first branch at an angle e.g. 45 degrees. The level sensor 2 is mounted in the second branch out of, but close to the flow of water through the waste pipe.

[0027] A connector e.g. a clamshell 40, described further below, joins the wye fitting 30 to the valve inlet 11.

[0028] In the example shown, while the waste pipe is empty, the valve 1 is closed. As water starts to fill the waste pipe (FIG. 3(a)) it approaches the branch of the wye fitting in which the sensor 2 is located. Water continues (FIG. 3(b)) to flow along the pipe 20 and is blocked (FIG. 3(c)) by the closed valve 1. As more water flow into the waste pipe 20, it starts to fill the wye branch 32 where the sensor 2 is located (FIG. 3(d)). When the sensor is covered (FIG. 3(e)) it sends a command signal to the motor (not shown) to cause the valve 1 to open. In a grey water system as mentioned above, for example, this then allows the accumulated water to be released into the flush system.

[0029] As mentioned above, it is important for reliable operation of the sensor and the valve that the sensor is fixed in the correct location and orientation. Whilst the sensor can be fixedly secured in the wye fitting, it is also important to ensure that the connection between the wye fitting and the valve inlet is such as to secure the position and orientation of the wye fitting itself.

[0030] Conventionally, in such systems, fittings and pipes are connected by a so-called clam shell connector 40 which is a one-piece connector consisting of two halves joined by a hinge area which allows the structure to come together to close. Such connectors are quick and easy to use and provide secure attachment of components. A clam shell connector, however, does not secure the relative orientation of two connected pipe components and without additional fixing components or adhesives, the connected pipes will be able to rotate relative to each other. This makes clam shells unsuitable for an arrangement in which the level sensor is provided in the wye fitting as described above.

[0031] One aspect of this disclosure, therefore, is to provide an alternative structure that enables a clam shell connector to be used to secure the parts together but ensure a fixed orientation of the connected parts. This is provided by means of an insert 50 that will now be described with reference to FIGS. 4, 5, 8 and 9.

[0032] The insert 50 is configured to be fitted into the valve inlet 11 and the wye fitting 30 such that it extends, in the flow path, to bridge the join between the valve and the wye fitting. The insert 50 is in the form of a ring or sleeve, so as not to hinder flow of the fluid, and is provided with locking features such that it is secured to the valve inlet and the wye fitted in a non-rotatable manner and such that the wye fitting cannot rotate relative to the wye fitting. The insert 50 may be provided by locking or keying features that engage with or mate with opposing features provided on the wye fitting and the valve inlet or that otherwise tightly engage e.g. by a form or friction fit with the wye fitting and the valve inlet. The locking features may be in the form of projections or latches 51 that engage in detents or slots 34 in the end of the wye fitting 30 and teeth 52 or protuberances that provide a form fit of friction fit with the valve inlet but other forms of locking may also be provided so long as rotation of the parts relative to each other is prevented due to the insert 50. In the preferred example, a friction fit is provided for connection to the valve inlet so that the insert 50 can be connected to any standard valve inlet ports using clamshells. The other side of the insert fits to the wye fitting which can be a custom part and various options are available for fitting the insert to this part. Thus, the insert can have different fittings on its two sides. The insert preferably has some flexibility and should have relative small dimensions to minimise disruption to the flow. A polymer insert has been found to work well. Metal and plastic inserts are also feasible. In environments where there is a lot of vibration or other forms of impact or harsh conditions, the insert 50 may be provided with a greater number of locking features e.g. circumferential teeth 53 as shown in FIG. 9. For use with a standard valve inlet/wye fitting, that has not been formed with cooperating locking means, teeth or other protuberances will provide a universal locking insert.

[0033] Although described for an assembly in which the sensor is mounted in a wye fitting, the improved connection could also have benefits in arrangements where the sensor is mounted in a simple pipe fitted to the valve inlet.

[0034] Another problem with sensors mounted as described above is that the area where the level sensor 2 is located can become contaminated with dirt or mud or other pollutants in the water. This can make the sensor less accurate or even damage the sensor, thus adversely affecting the water flow function and also risks the growth of fungus/development of bacteria in the system.

[0035] According to another aspect of the disclosure, therefore, the assembly is constructed to provide cleaning of the sensor during use. This aspect, as will be described below, provides benefits independently of and also together with the connection insert feature described above.

[0036] The second aspect will be described with particular reference to FIGS. 6, 7 and 10.

[0037] As above, the level sensor 2 is mounted in the second branch 32 of the wye fitting 30. Here, in this embodiment, though, one or more additional nozzles 60 or flow channels are provided from the first branch 31, upstream of the opening of the second branch 32, to a downstream location of the second branch 32, where the sensor 2 is located. These nozzles 60 are tapered from a wider opening 61 at the interface with the first branch 31 to a narrower opening 62 at the interface with the second branch 32. The tapering increases the water pressure at the smaller opening. The nozzles 60 may also be provided with a filter 65, shown in FIG. 10, to prevent the ingress of larger contaminant particles. The filter could be a solid filter formed as an integral part of the nozzle, having a shape/diameter to restrict flow.

[0038] The flow, with this modified wye fitting, will be described with reference to FIG. 7. As water (e.g. drain water) begins to flow in the waste pipe 20 (FIG. 7(a)) some of that water will be diverted into the nozzle 60 at the wider opening 61, the pressure of that water will be increased at the smaller opening 62 and will be directed as a jet at the sensor 2 at the higher pressure to clean the sensor 2 (FIG. 7(b)). This is in contrast to the first design, without the nozzles, where, as seen in FIG. 3, the water does not reach the sensor 2 until it has filled the first branch 31. As water continues to flow in the first branch and, at the same time in the second branch, from the nozzle (FIG. 3(c)), the sensor 2 becomes fully covered before the first branch 31 has filled, thus causing the valve 1 to open (FIG. 7(d)) sooner than seen in FIG. 3. The valve is then already open as the water in the first branch reaches it (FIG. 7(e)).

[0039] In addition to providing cleaning of the sensor during operation as described above, the nozzle design provides further advantages over the design without the nozzles described above.

[0040] In the design without the nozzles, as mentioned above, water first flows to the closed valve 1 (FIG. 3(c)) before starting to cover the sensor (FIG. 3(e)). Because the water pressure flowing into the second branch is low, there is a risk of air bubbles developing in the sensor area which can affect the area of coverage of the sensor and, therefore, its accuracy. There is a risk, then, that the sensor senses the full state later than it should. With the improved nozzle design, the sensor is cleaned and, in addition, the risk of creation of air bubbles is reduced.

[0041] The modified wye fitting can be designed to be attached to any valve type, with or without the connector described above in the first aspect.

[0042] The nozzles 60 are formed integrally with the wye fitting 30. This could be performed by additive manufacturing to reduce costs and manufacturing/assembly time. Also, the nozzles 60 with integral filter 65 can be additively manufactured.

[0043] The aspects of the assembly of this disclosure described above provide a number of advantages over existing arrangements. The parts can be additively manufactured thus reducing costs. The connector feature provides for quicker assembly without the need for additional fastening components while still using a standard clam shell clamp. With the nozzle design, the valve detects water flow sooner as the risk of a water gap is reduced. The features of the disclosure can be used with many types of valve and in many types of flow system and with different fluids.