Patent Description:
Household appliances, such as washing machines or dishwashers, which operate using water, typically comprise an inlet valve for regulating and adjusting the amount of water supplied to the household appliance from an external water source, such as a water tap. For this purpose, inlet valves known in the art generally comprise inlet ducts, outlet ducts, controllable valves and means for determining a flow rate of water through the inlet valve.

There are various challenging technical requirements for the design of inlet valves for household appliances. In particular, it is a general constraint that the amount of space available inside the household appliance is limited. When in operation, household appliances, in particular washing machines may cause significant vibrations which puts increased demands on the assembly of the individual components. Furthermore, the components of the household appliance have to be able to operate in an environment potentially containing large amounts of water.

German utility model <CIT> discloses an inlet valve in form of a solenoid valve apparatus comprising a hollow valve body with an inlet and two outlets for a flow of a fluid, especially water. Between the inlet and the two outlets, a chamber is defined in the valve body, in which a valve seat is provided. A valve body is provided in the valve seat for controlling the communication between the inlet and outlet. In the area of the inlet of the valve body, an integral flow line is provided for the flow of the fluid, wherein the flow line is configured to accommodate a turbine-flow meter. The solenoid valve apparatus further comprises a receiving space for accommodating a control circuit board. The receiving space is located in the area of the flow line, inside which a plate seat is formed. The plate seat is located outside of the flow line and is configured to accommodate the control circuit board. The control circuit board itself is equipped with a sensor for receiving a signal provided by the turbine flow meter. The valve body and the receiving space are unitarily formed from molded plastic. A double wall is formed by a portion of a peripheral wall, which defines the plate seat, and by a wall of the flow line. The portion of the peripheral wall portion is separated from the wall of the flow line by an air passage.

While the inlet valves known in the art, such as the solenoid valve apparatus of <CIT> can generally be considered satisfactory in view of the technical requirements discussed above. However, there remains the need for improved inlet valves. Moreover, there remains the need for inlet valves which improve the economics of producing household appliances.

<CIT> discloses a device for treating a liquid flow for appliances and systems supplied with said liquid. <CIT> discloses a hydraulic control device for liquid-conducting household appliances or systems. <CIT> discloses a measurement unit, particularly for hydraulic ducts. <CIT> discloses an electronic faucet including a wireless module facilitating remote control of an electrically operable valve. <CIT> discloses a method and apparatus for metering building structures having a plurality of service outlets each having control valves. <CIT> discloses a fluid governing system. None of those documents disclose an arrangement of valve assembly having a flow rate indicator configured to provide a quantity indicative of a fluid flow rate through a fluid path in the valve assembly, and flowmeter comprising a sensor configured to detect that quantity, and wherein the flowmeter and valve assembly are separate entities that are removably attachable to one another.

In a first aspect, the present invention addresses the above discussed needs by providing a flowmeter for determining a fluid flow rate through an associated valve assembly as defined in claim <NUM>. The flowmeter comprises a housing, a sensor arrangement disposed in the housing, and a coupling portion provided at the housing. The sensor arrangement comprises at least one sensor configured to detect a quantity indicative of the fluid flow rate through the valve assembly. The coupling portion is configured to engage with an associated counter-coupling portion of the valve assembly for coupling the flowmeter to the valve assembly in an orientation with respect to the valve assembly selectable from a group comprising at least a first orientation and a second orientation.

In a second aspect, the present invention addresses the above discussed needs by providing a valve assembly as defined in claim <NUM> which comprises a valve body, at least one valve, a flow rate indicator and a counter-coupling portion. The valve body comprises at least one inlet duct, at least one outlet duct and a fluid path connecting the at least one inlet duct and the at least one outlet duct. The at least one valve is configured to control a fluid flow rate through the fluid path. The flow rate indicator is configured to provide a quantity indicative of the fluid flow rate through the fluid path, the quantity being detectable by a sensor of an associated flowmeter. The counter-coupling portion is configured to couple with an associated coupling portion of the flowmeter of the first aspect for coupling the flowmeter to the valve assembly in an orientation with respect to the valve assembly selectable from a group comprising at least a first orientation and a second orientation.

In a third aspect, the present invention addresses the above discussed needs by providing an inlet valve for a household appliance, such as a washing machine, which is defined in claim <NUM> and which comprises the valve assembly of the second aspect and the flowmeter of the first aspect.

In a fourth aspect, the present invention addresses the above discussed needs by providing a household appliance, such as a washing machine, which is defined in claim <NUM> and which comprises a valve assembly of the second aspect.

The present invention enables to attach a flowmeter to a valve assembly in different orientations, such as in an orientation freely selectable from a group comprising at least a first orientation and a second orientation. Thereby, the present invention is able to meet the space constraints of different household appliances, like washing machines by coupling the flowmeter of the first aspect to the valve assembly of the second aspect in a suitable one of the selectable orientations. The flowmeter of the first aspect, the valve assembly of the second aspect and the inlet valve of the third aspect are therefore readily employable in different types of washing machines, without the need for substantial modifications, if any.

It has to be understood that the present invention is not limited to a group of orientations comprising a first orientation and a second orientation in which the flowmeter is selectively attachable to the valve assembly. As will be clear from the following description, the flowmeter according to the first aspect, the valve assembly according to the second aspect, the inlet valve according to the third aspect and the household appliance according to the fourth aspect can optionally allow to selectively attach the flowmeter to the valve assembly in more than two orientations, for example in at least three orientations, at least four orientations, at least five or orientations or at least six orientations or more.

In a preferred embodiment, in all aspects of the present invention, the coupling portion is configured to removably couple with the associated counter-coupling portion of the valve assembly. Thus, the choice of orientation is reversible, i.e. the flowmeter may be removed from the valve assembly and re-coupled to the valve assembly in a different orientation.

Alternatively or additionally, in all aspects of the present invention, the at least one sensor is arranged in an encapsulated section of the housing. Thereby, the sensor may advantageously be protected against coming into contact with moisture and/or water.

Alternatively or additionally, in all aspects of the present invention, the housing comprises a mating surface and the coupling portion is configured such that, when the flowmeter is coupled to the valve assembly in an orientation selectable from the group comprising at least the first and second orientation, the mating surface engages an abutting surface of the valve assembly. Preferably, the valve assembly comprises at least one abutting surface. The engagement between the mating surface and the abutting surface may contribute to maintaining the predetermined distance under different loading conditions. Preferably, the sensor of the sensor arrangement is disposed in the housing beneath the mating surface. Alternatively or additionally, the valve assembly comprises a plurality of abutting surfaces and the mating surface engages a selected one of the plurality of abutting surfaces depending on the selected orientation of the group of orientations. In other embodiments, the valve assembly comprises a single abutting surface and the mating surface engages the single abutting surface in each orientation of the group of orientations.

Alternatively or additionally, in all aspects of the present invention, the coupling portion is configured such that, when the flowmeter is coupled to the valve assembly in an orientation selectable from the group comprising at least the first and second orientation, the coupling portion biases the mating surface against a respective one of the at least one abutting surface. The bias may reduce the risk that the mating surface separates from the abutting surface due to external loads, such as vibrational acceleration. Thereby, the reliability of the flow rate measurement may be increased, since the predetermined distance is maintained with increased probability. In particular, the formation of a gap between the mating surface and the abutting surface may be prevented.

Alternatively or additionally, in all aspects of the present invention, the coupling portion comprises a receiving portion configured such that, when the flowmeter is coupled to the valve assembly in an orientation selectable from the group comprising at least the first and second orientation, the counter-coupling portion of the valve assembly is least partially recessed in the receiving portion. The total dimensions of the inlet valve may thereby advantageously be reduced.

Alternatively or additionally, in all aspects of the present invention, the coupling portion comprises a plurality of coupling elements, wherein each coupling element is configured to engage with a respective counter-coupling element of a plurality of counter-coupling elements of the counter-coupling portion. Preferably, each coupling element is configured to selectively engage with each one of the counter-coupling elements. More preferably, each coupling element is configured to engage a selected one of the counter-coupling elements depending on a selected orientation from the group of orientations. Preferably, the coupling portion comprises at least a first coupling element and a second coupling element, wherein each of the at least first and second coupling elements is configured to engage a selected one of at least a first counter-coupling element and a second counter-coupling element of the counter-coupling portion of the valve assembly so as to selectively secure the flowmeter in an orientation chosen from the group comprising at least the first and second orientation. Preferably, the first coupling element is configured to engage the first counter-coupling element in the first orientation and to engage the second counter-coupling element in the second orientation. Alternatively and or additionally, the second coupling element is configured to engage the second counter-coupling element in the first orientation, and to engage the first counter-coupling element in the second orientation.

Alternatively or additionally, in all aspects of the present invention, the coupling portion comprises a first leg and a second leg, the first and second leg being spaced apart to define the receiving portion therebetween.

Alternatively or additionally, in all aspects of the present invention, the counter-coupling portion comprises a plurality of counter-coupling elements, wherein each counter-coupling element is configured to engage with a respective coupling element of the plurality of coupling elements of the coupling portion. Preferably, each counter-coupling element is configured to selectively engage with each one of the coupling elements. More preferably, each counter-coupling element is configured to engage a selected one of the coupling elements depending on a selected orientation from the group of orientations. Preferably, the counter-coupling portion comprises at least a first counter-coupling element and a second counter-coupling element, wherein each of the at least first and second counter-coupling elements is configured to engage a selected one of at least a first coupling element and a second coupling element of the counter-coupling portion of the valve assembly so as to selectively secure the flowmeter in an orientation chosen from the group comprising at least the first and second orientation. Preferably, the first counter-coupling element is configured to engage the first coupling element in the first orientation and to engage the second coupling element in the second orientation. Alternatively and or additionally, the second counter-coupling element is configured to engage the second coupling element in the first orientation, and to engage the first coupling element in the second orientation.

Alternatively or additionally, in all aspects of the present invention, the first coupling portion is provided at the first arm and the second coupling portion is provided at the second arm.

Alternatively or additionally, in all aspects of the present invention, the counter-coupling portion is provided at an annular outer surface of a wall section of the valve body which encloses the fluid path. Preferably, the annular outer surface is arranged concentrically with the flow axis defined by the fluid path. Alternatively or additionally, the counter-coupling elements are provided at the annular outer surface of the wall section of the valve body. Preferably, the counter-coupling elements are spaced around the annular outer surface at regular intervals. More preferably, an angle formed between two adjacent counter-coupling elements equals to <NUM>° divided by the total number of counter-coupling elements. For example, when the counter-coupling portion comprises two counter-coupling elements, it is preferred that the two counter-coupling elements are spaced around the annular outer surface at a <NUM>° separation.

Alternatively or additionally, in all aspects of the present invention, the coupling portion and/or the counter-coupling portion is configured such that, when the flowmeter is coupled to the valve assembly in an orientation selectable from the group comprising at least the first and second orientation, the at least one sensor is in a detection position. The detection position is a position suitable for the sensor to detect the quantity indicative of the fluid flow rate.

Alternatively or additionally, in all aspects of the present invention, the coupling portion and/or the counter-coupling portion is configured such that, when the flowmeter is coupled to the valve assembly in an orientation selected from the group comprising at least the first and second orientation, the at least one sensor is positioned at a predetermined distance from the flow rate indicator. In particularly preferred embodiments, the predetermined distance is substantially equal in each one of orientations comprised in the group of orientations. Thereby, the prerequisites for a reliable detection of the flow rate may be maintained in each one of the orientations comprised in the group of orientations.

Alternatively or additionally, in all aspects of the present invention, the coupling portion and/or the sensor arrangement is integrally formed with the housing. Preferably, the coupling portion is molded with the housing in a molding step. Preferably, the sensor is molded onto the sensor arrangement. More preferably, the encapsulated section of the housing is formed by molding the housing onto the sensor arrangement. This simplified production of the flow meter considerably.

Alternatively or additionally, in all aspects of the present invention, the counter-coupling portion is integrally formed with the valve body. Preferably, the counter-coupling portion is molded with the valve body in a molding step.

Alternatively or additionally, in all aspects of the present invention, the flow rate indicator comprises an impeller, which is provided in a portion of the fluid path. Preferably, the impeller is arranged such that its plane of rotation is perpendicular to a flow axis defined by the portion of the fluid path. The impeller is configured to be rotated by the fluid flow in the fluid path. The rate of rotation of the impeller is therefore indicative of the fluid flow rate of the flow in the fluid path. More preferably, an axis of rotation of the impeller coincides with the flow axis.

Alternatively or additionally, in all aspects of the present invention, the detectable quantity is a magnetic field. Preferably, the magnetic field is provided by at least one magnetic portion of the flow rate indicator of the valve assembly. In further preferred embodiments, the magnetic portion comprises a material chosen from a group comprising ferrite and rare earth metals, such as neodymium. Rare earth metals, such as neodymium may be preferred for its magnetic properties. Ferrite may be preferred for its price.

Alternatively or additionally, in all aspects of the present invention, the predetermined distance is adapted to the magnetic portion. In preferred embodiments, the predetermined distance is adapted to a material comprised in the magnetic portion. In particularly preferred embodiments, the predetermined distance is adapted to the magnetic portion comprising ferrite. Alternatively or additionally, the predetermined distance is adapted to the magnetic portion comprising a rare earth metal, such as neodymium. In particularly preferred embodiments, the predetermined distance is a mean value between a predetermined distance adapted to a magnetic portion comprising ferrite and a predetermined distance adapted to a magnetic portion comprising a rare earth metal, such as neodymium. Thus, the present invention may be used with rare earth metal magnets, such as neodymium magnets, as well as ferrite magnets without having to change the dimensions of either flowmeter or valve assembly.

Alternatively or additionally, in all aspects of the present invention, the impeller comprises the magnetic portion. The magnetic portion has a distance from the rotational axis of the impeller. Thereby, the variation of the magnetic field provided by the magnetic portion when rotating with the impeller is indicative of the fluid flow rate of the flow in the fluid path. Alternatively or additionally, the flow rate indicator comprises a plurality of magnetic portions arranged on a circle around the flow axis defined by the fluid path at alternating polarity. Preferably, the plurality of magnetic portions is arranged on the impeller and radially aligned with the axis of rotation at alternating polarity. In other words adjacent magnetic portions have poles of opposing polarity oriented radially outward. Alternating polarity provides a detectable polarity change as a further indicator for the flow rate and/or as a measure to perform a consistency check of the detected magnetic field.

Alternatively or additionally, in all aspects of the present invention, the sensor of the sensor arrangement of the flowmeter is a hall sensor. A hall sensor may allow the flowmeter to detect the quantity indicative of the flow rate in the fluid path while being physically separated from the fluid path. In particular, the hall sensor allows to detect a magnetic field provided by the flow rate indicator. It has to be understood however, that any other sensor and indicator combination known in the art and capable of measuring a rotation rate of impeller may be used instead, such as capacitive sensors wherein the detectable quantity is an electric field.

Alternatively or additionally, in all aspects of the present invention, each of the orientations comprised in the group of orientations is located in a common plane. In further preferred embodiments, the common plane is arranged perpendicular to a flow axis defined by the fluid path. In further or additional preferred embodiments, the common plane corresponds to a plane of rotation of the impeller of the flow rate indicator. In further or additional preferred embodiments, the detection position lies in the common plane. Alternatively or additionally, the predetermined distance is a distance in the common plane.

Alternatively or additionally, in all aspects of the present invention, the orientations comprised in the group of orientations are disposed on a circle concentric with a flow axis defined by the fluid path. Preferably, the orientations comprised in the group of orientations are defined by an orientation of a major axis of the flowmeter, such as an axis of symmetry of the flowmeter, in a plane perpendicular to the flow axis. More preferably, the circle on which the orientations are disposed is arranged in the plane perpendicular to the flow axis. It is alternatively or additionally preferred that the orientations comprised in the group of orientations are defined by vectors extending radially outward from the flow axis. Preferably, the orientations are disposed at regular intervals along a circumference of the circle. Alternatively or additionally, an angle formed between two adjacent orientations, i.e. two orientations neighboring each other in a circumferential direction of the circle, equals to <NUM>° divided by the number of orientations comprised in the group of orientations. Alternatively or additionally, an angle formed between adjacent orientations is <NUM>°, <NUM>°, <NUM>°, <NUM>°, <NUM>° or <NUM>°.

Alternatively or additionally, in all aspects of the present invention, each orientation comprised in the group of orientations is aligned with a radial direction extending from the flow axis formed by the fluid path.

It has to be understood the present invention is not limited to usage in household appliances. As will be clear from the following description, the present invention is readily adaptable to any application requiring determination and/or control of a flow rate of a fluid. In some embodiments of the first, second, third or aspect of the present invention, the flowmeter is configured to determine and/or control a flow rate of a liquid. In preferred embodiments, the liquid is water. In other preferred embodiments, the liquid is a substance other than water, such as oil. Alternatively or additionally, the first, second, third or fourth aspect of the present invention is configured to determine and/or control a fluid flow rate of a gas.

Alternatively or additionally, in all aspects of the present invention, the valve assembly has at least one inlet duct (e.g. one, two, three, or four inlet ducts) and a number of outlet ducts greater than two, for example three or more outlet ducts, four or more outlet ducts or five or more outlet ducts. Alternatively or additionally, the valve assembly has at least one outlet duct (e.g. one, two, three or four outlet ducts) and a number of inlet ducts greater than one, for example two or more outlet ducts, three or more outlet ducts or four or more outlet ducts.

Further advantages and preferred embodiments and of the present invention will be described in the following together with the drawings listed below.

A preferred embodiment of an inlet valve V is depicted in <FIG> and comprises a valve assembly <NUM> and a flowmeter <NUM> removably attached to the valve assembly <NUM>. As stated above, the present invention enables to attach flowmeter <NUM> to valve assembly <NUM> in an orientation selectable from a group of different orientations, such as in a selectable one of a first orientation (as depicted for example in <FIG> and <FIG>) and a second orientation (as depicted for example in <FIG>).

In preferred embodiments of the present invention, inlet valve V is configured for use in a household appliance. In the particularly preferred embodiment of <FIG>, inlet valve V is configured for use in a washing machine. In other preferred embodiments, inlet valve V can be configured for use in a dishwasher. When used in a washing machine or in a dishwasher, inlet valve V is configured to release detergent from one or more detergent storages of the washing machine or dishwasher. For this purpose, inlet valve V is configured to control water flow from an external water supply to the one or more detergent containers, from which the detergent is flushed to an application site.

In the particularly preferred embodiment depicted in <FIG>, valve assembly <NUM> comprises a valve body <NUM> forming an inlet duct <NUM>, a first outlet duct <NUM> and a second outlet duct <NUM>. Inlet duct <NUM> is configured to be connected to an external water supply line, such as a water tap. An inflow stream IF is provided by the external water supply and enters valve assembly <NUM> through inlet duct <NUM>. First outlet duct <NUM> and second outlet duct <NUM> are configured to be connected to internal water distribution lines (not depicted) of the washing machine. First outlet duct <NUM> is connectable to a first detergent storage via a first internal water distribution line. Likewise, second outlet <NUM> duct is connectable to a second detergent storage via a second internal water distribution line. As indicated by solid black lines in <FIG>, a flow path <NUM> is formed in valve body <NUM>. Flow path <NUM> extends from inlet duct <NUM> to the first outlet duct <NUM> and the second outlet duct <NUM>, and enables inflow stream IF entering at inlet duct <NUM> to pass through valve assembly <NUM> and exit as first outflow stream OF1 via first outlet duct <NUM> and as second outflow stream OF2 via second outlet duct <NUM>. At a junction <NUM>, flow path <NUM> branches off into a first branch 14a, leading to first outlet duct <NUM>, and a second branch 14b leading to second outlet duct <NUM>.

In the depicted embodiment, inlet duct <NUM>, first outlet duct <NUM> and second outlet duct <NUM> are each formed from a respective cylindrical protrusion <NUM>, <NUM>, <NUM> of valve body <NUM>. Cylindrical protrusion <NUM> forming inlet duct <NUM> has a threaded outer surface connectable to a corresponding threaded portion of the external water supply line. Likewise, cylindrical protrusion <NUM> forming first outlet duct <NUM> and cylindrical protrusion <NUM> forming second outlet duct <NUM> each have a threaded outer surface connectable to a corresponding threaded portion of a respective internal water distribution line. It has to be understood that any other flow-bearing coupling known in the art can be used instead of a threaded connection, such as interference fit couplings or press fit couplings.

To control outflow stream OF <NUM> and outflow stream OF <NUM>, valve assembly <NUM> comprises a first valve (not depicted) and a second valve (not depicted). A first valve seat <NUM> is formed in valve body <NUM> and configured to receive the first valve. First valve seat <NUM> is positioned downstream of junction <NUM>, and above first branch 14a of flow path <NUM>. First valve seat <NUM> is configured such that a control element of the first valve can extend into first branch 14a to adjust an available flow cross-section of first branch 14a. Likewise, second valve seat <NUM> is positioned downstream of junction <NUM>, and above second branch 14b of flow path <NUM>. Second valve seat <NUM> is configured such that a control element of the second valve can extend into second branch 14b to adjust an available flow cross-section of second branch 14b. By controlling the available flow cross-sections of first branch 14a and second branch 14b, valve assembly <NUM> controls the flow rate of first outflow stream OF1 and the flow rate of second outflow stream OF2 depending on the flow rate of inflow stream IF. The first and second valve are configured to receive input signals of an electronic control unit of the washing machine and adjust the respective flow cross-sections accordingly. Any valve type known in the art, controllable by an electronic control unit and capable of adjusting an available cross-section of a flow path, is suitable for use in all aspects of the present invention. In preferred embodiments, the first and second valve are electromechanically operated valves, in particular solenoid valves. In the particularly preferred embodiment of <FIG>, the washing machine is configured to adjust a flow rate of first outflow stream OF <NUM> according to an amount and/or type of detergent present in the first detergent storage. Likewise, the washing machine is configured to adjust a flow rate of second outflow stream OF <NUM> according to an amount and/or type of detergent present in the second detergent storage. In particularly preferred embodiments, the washing machine is configured such that a simultaneous supply of first and second outflow stream OF <NUM> and OF <NUM> flushes a third detergent storage.

It has to be understood that the present invention is not limited to the number of inlet ducts and outlet ducts of the preferred embodiment of <FIG>. It generally suffices that the valve assembly has at least one inlet duct and at least one outlet duct, and the particular number of inlet ducts and outlet ducts can be adapted as needed.

As will be explained in greater detail in the following sections, valve assembly <NUM> further comprises a counter-coupling portion <NUM> which is configured to engage with a coupling portion <NUM> of flowmeter <NUM> to selectively and removably attach flowmeter <NUM> in either one of the first orientation and second orientation. Valve assembly <NUM> further comprises at least one flow rate indicator <NUM> which is configured to provide a quantity indicative of the fluid flow rate through fluid path <NUM>, the quantity being detectable by a sensor <NUM> of flowmeter <NUM>.

As shown in <FIG>, flowmeter <NUM> is provided as an entity separate from and removably attachable to valve assembly <NUM>. Flowmeter <NUM> is configured to determine the fluid flow rate of inflow flow stream IF at inlet duct <NUM>, thereby enabling the electronic control unit of the washing machine to control the first and second valve of valve assembly <NUM> as required. Flowmeter <NUM> comprises a housing <NUM>, which houses a sensor arrangement <NUM> comprising at least one sensor <NUM>. As will be explained in greater detail below, flowmeter <NUM> comprises a coupling portion <NUM> configured to selectively and removably attach flowmeter <NUM> to valve assembly <NUM> in either one of the first and second orientation.

The cross-sectional views of <FIG>, <FIG> and <FIG> expose sensor arrangement <NUM>, which is shielded from view by housing <NUM> in <FIG>. In the preferred embodiment of <FIG>, sensor arrangement <NUM> further comprises a circuit board <NUM> carrying circuitry <NUM> for processing signals received from sensor <NUM>. Circuit board <NUM> further comprises a plurality of contact terminals <NUM> disposed on a portion of circuit board <NUM> that forms a contact section <NUM>. Sensor <NUM> and circuitry <NUM> are disposed on a portion of circuit board <NUM> that forms a circuit section <NUM>, with sensor <NUM> being positioned at an end of circuit section <NUM> that lies opposite from an end of circuit section <NUM> that is adjacent to contact section <NUM>. Housing <NUM> comprises an encapsulated section <NUM> (indicated by dashed lines in <FIG>) partially covering circuit board <NUM>, such that circuitry <NUM> and sensor <NUM> lie within encapsulated section <NUM>, and contact terminals <NUM> lie outside of encapsulated section <NUM>. In other words, contact section <NUM> corresponds to a portion of contact board <NUM> which is positioned outside of encapsulated section <NUM>. As will be described in the following sections, encapsulated section <NUM> forms a water resistant barrier around circuit board <NUM>. Housing <NUM> further comprises a planar mating surface <NUM> on an outer surface thereof. As can be seen for example in <FIG> and <FIG>, sensor <NUM> is positioned within housing <NUM> below mating surface <NUM>.

Contact terminals <NUM> are configured to be contactable by respective corresponding contact terminals of a data cable (not depicted) which is connected to the electronic control unit of the washing machine. In other words, flowmeter <NUM> comprises a data link, configured to provide the signals received from sensor <NUM> to the control unit of the washing machine. In the embodiment of <FIG>, housing <NUM> of flowmeter <NUM> comprises a connection section <NUM> forming a socket <NUM> in which contact terminals <NUM> are positioned. Socket <NUM> is configured to receive a corresponding plug of the data cable. It has to be understood that flowmeter <NUM> can comprise alternative data links. In some preferred embodiments, the data link is provided by a wireless connection, thereby eliminating the need for connection section <NUM>, socket <NUM> and contact terminals <NUM>. In other preferred embodiments, a wireless datalink is combined with a connection section configured to be connected with a power supply line. In the embodiment of <FIG>, power is supplied to flowmeter <NUM> at contact terminals <NUM>.

In <FIG>, sensor arrangement <NUM> of flowmeter <NUM> is removed from housing <NUM> and exposed for view. Sensor arrangement <NUM> comprises circuit board <NUM> and a support structure <NUM>. Circuit board <NUM> is disposed on a top surface of a main portion of support structure <NUM>, thus leaving a top surface of contact board <NUM> (on which circuitry <NUM>, sensor <NUM> and contact terminals <NUM> are placed) uncovered. The main portion of support structure <NUM> comprises a circuitry portion 138a on which circuit section <NUM> of circuit board <NUM> is arranged, and a terminal portion 138b on which contact section <NUM> of circuit board <NUM> is arranged. As shown in <FIG>, support structure <NUM> is substantially symmetrical in shape with a respective axis of symmetry extending from circuitry portion 138a to terminal portion 138b. A first leg <NUM> and a second leg <NUM> extend from opposite sides of the main portion of support structure <NUM>. Each of first and second legs <NUM>, <NUM> comprise a base portion 142a, 144a, which is angled to the axis of symmetry of support structure <NUM>, and an extension portion 142b, 144b, which is substantially parallel to the axis of symmetry of support structure <NUM>. Base portions 142a, 142b connect respective leg <NUM>, <NUM> to the main portion of support structure <NUM> at a boundary region between circuitry portion 138a and terminal portion 138b. Base portions 142a, 144a then extend outward from the main portion and in a direction away from terminal portion 138b. Extension portions 142b, 144b extend at an angle from respective ends of base portions 142a, 144a in a direction away from terminal portion 138b. Extension portions 142b, 144b are substantially parallel to one another. Support structure <NUM> is substantially flat, i.e. its thickness is substantially smaller compared to its width and length. In some embodiments, the top surface of support structure <NUM> is even. In some embodiments, the top surface of support structure <NUM> is structured. In particularly preferred embodiments, a portion of the top surface of support structure <NUM> which forms part of socket <NUM> is recessed compared to the remaining portions of the top surface.

In preferred embodiments, producing flowmeter <NUM> comprises a multi-step molding process. Molding processes are particularly preferred for their potential to economize production of flowmeter <NUM>. In a first molding step, support structure <NUM> is molded. Circuit board <NUM> may be attached to support structure <NUM> in a separate step after the first molding step. In preferred embodiments, support structure <NUM> is molded onto circuit board <NUM>, thus eliminating the need for a separate attachment step. In a second molding step, housing <NUM> is molded onto sensor arrangement <NUM>. Encapsulated section <NUM> of housing <NUM> is formed by a portion of molded material which covers the remaining exposed portions of circuit board <NUM> with the exception of contact section <NUM>. In the embodiment of <FIG>, the remaining exposed portion of circuit board <NUM> is its top surface, which is oriented towards the viewer in <FIG>. Forming encapsulated section <NUM> in this manner is particularly preferred for its potential to reduce the effort necessary for sealing circuitry <NUM> against water ingress compared to conventional methods.

In the particularly preferred embodiment of <FIG>, coupling portion <NUM> is integrally formed with housing <NUM> in the second molding step. When integrally formed, housing <NUM> and coupling portion <NUM> form a monolithic flowmeter housing <NUM>. In alternative embodiments, housing <NUM> and coupling portion <NUM> are formed separately and connected in a subsequent step to form flowmeter <NUM>.

When formed in the above-described multi-step molding process, housing <NUM>, coupling portion <NUM> and support structure <NUM> each comprise a molded material, preferably a thermoplastic, thermosetting or elastomeric polymer or any suitable combination thereof. In some embodiments, the same molded material is used for housing <NUM>, coupling portion <NUM> and support structure <NUM>. In other embodiments, housing <NUM>, coupling portion <NUM> and support structure <NUM> are formed from different molded materials.

Coupling portion <NUM>, as best depicted in <FIG>, comprises a first leg <NUM> and a second leg <NUM> extending in a direction away from housing <NUM>. Each of first and second legs <NUM> and <NUM> comprise a respective base 120a, 122a and a respective extension portion 120b, 122b. Base 120a connects first leg <NUM> to connection section <NUM> of housing <NUM>. Likewise, base 122a connects second leg <NUM> to connection section <NUM> of housing <NUM>. Each of base 120a, 122a extend from opposite sides of housing <NUM> at an angle in a direction away from connection section <NUM>. Extension portions 120b, 122b extend at an angle from their respective base 120a, 122a in parallel to one another and in a direction away from connection section <NUM>. Thus, legs <NUM>, <NUM> of attachment structure <NUM> are similar in shape to legs <NUM>, <NUM> of support structure <NUM>. When formed in the above described two-step molding process, legs <NUM>, <NUM> are formed from molded material which encloses legs <NUM>, <NUM>. A space separating first and second legs <NUM> and <NUM> defines a receiving portion <NUM> for receiving at least a portion of counter-coupling portion <NUM> of valve assembly <NUM> therein. As shown for example in <FIG>, extension portions 120b, 122b of attachment structure <NUM> are longer than extension portions 142b, 144b of support structure <NUM>, i.e. they extend further in a direction away housing <NUM>. Receiving portion <NUM> is located in the space provided by the additional length of extension portions 120b, 122b. When flowmeter <NUM> is attached to counter-coupling portion <NUM> of valve assembly <NUM>, a portion of valve assembly <NUM> forming counter-coupling portion <NUM> is partially recessed in receiving portion <NUM>, reducing the overall dimensions of inlet valve V.

<FIG> is a view of inlet valve V cut in a plane indicated by dashed line <NUM>-<NUM> in <FIG>. In <FIG>, segments of inlet valve V are cut along dashed line <NUM>-<NUM> indicated in <FIG>. As depicted in <FIG>, <FIG> and <FIG>, coupling portion <NUM> also comprises a first coupling element <NUM> and a second coupling element <NUM>. In the embodiment of <FIG>, first coupling element <NUM> is integrally formed with first leg <NUM> and extends from housing <NUM> in a direction away from connection section <NUM>. Likewise, second coupling element <NUM> is integrally formed with second leg <NUM> and extends from housing <NUM> in a direction away from connection section <NUM>. First and second coupling elements <NUM>, <NUM> each comprise a respective connection portion 114a, 116a which connects coupling elements <NUM>, <NUM> to housing <NUM>. In the embodiments of <FIG>, connection portions 114a, 116a are formed from molded material that fills a space between housing <NUM> and respective legs <NUM>, <NUM>, resulting from respective base portions 120a, 122a extending away from housing <NUM>. Coupling elements <NUM>, <NUM> each further comprise a respective retaining portion 114b, 116b. In the depicted embodiment, each retaining portion 114b, 116b is forked into a pair of parallel prongs 150a, 150b, 154a, 154b. Each prong 150a, 150b, 154a, 154b, ends in a respective locking lug 152a, 152b, 156a, 156b. Locking lugs 152a, 152b, 156a, 156b are substantially arrow-shaped, with a tip portion defining a section of increased width of retaining portions 114b, 116b.

Counter-coupling portion <NUM> of valve assembly <NUM>, best depicted in <FIG> and <FIG>, is provided at a wall section <NUM> of valve body <NUM> which encloses fluid path <NUM> (dashed line in <FIG>) in a segment downstream of inlet duct <NUM> and upstream of junction <NUM>. Wall section <NUM> comprises an annular outer surface <NUM> from which an upstream wall segment <NUM> and a downstream wall segment <NUM> extend radially outward. Counter-coupling portion <NUM> is defined between upstream wall segment <NUM> and downstream wall segment <NUM>. A first bracket <NUM> and a second bracket <NUM> which extend radially outward from outer surface <NUM>. First bracket <NUM> and second bracket <NUM> form counter-coupling elements of counter-coupling portion <NUM> and are arranged at a <NUM>° separation from one another in a plane perpendicular to fluid path <NUM>, i.e. in the plane of <FIG>. As indicated by dashed line <NUM>-<NUM> in <FIG>, the view of <FIG> cuts through first bracket <NUM> and visualizes how each of first and second brackets <NUM>, <NUM> connect upstream wall segment <NUM> and downstream wall segment <NUM>. Brackets <NUM>, <NUM> each comprise an eyelet <NUM>, which is formed by a respective opening extending through brackets <NUM>, <NUM> in a direction substantially tangential to annular outer surface <NUM> at the respective location of brackets <NUM>, <NUM>. As depicted in <FIG>, respective indents <NUM>, <NUM> are formed in upstream wall segment <NUM> and downstream wall segment <NUM> immediately adjacent first bracket <NUM>. Corresponding indents (not depicted) are formed immediately adjacent second bracket <NUM>. Indents <NUM>, <NUM> are optional and may provide further safety against unintended separation of flowmeter <NUM> from valve assembly <NUM>. Wall section <NUM> further comprises a pair of abutting surfaces <NUM> arranged on opposite sides of valve body <NUM>. Abutting surfaces <NUM> extend in parallel to fluid path <NUM> and perpendicular to a direction defined by axis extending through the eyelets of brackets <NUM>, <NUM>.

To attach flowmeter <NUM> to valve assembly <NUM>, flowmeter <NUM> is positioned so that receiving portion <NUM> is oriented towards counter-coupling portion <NUM>. Coupling portion <NUM> is positioned between upstream wall <NUM> and downstream wall <NUM>. First coupling element <NUM> is aligned with eyelet <NUM> of first bracket <NUM> and second coupling element <NUM> is aligned with the eyelet of second bracket <NUM>. Flowmeter <NUM> is then advanced so that first and second coupling elements <NUM>, <NUM> are simultaneously threaded into the respective eyelets of first and second bracket <NUM>, <NUM>. Prongs 150a, 150b, 154a, 154b are generally shaped to follow the contour of annular outer surface <NUM> of counter-coupling portion <NUM>. Thereby, advancing receiving portion <NUM> over counter-coupling portion <NUM> may be facilitated. The connection between coupling elements <NUM>, <NUM> and brackets <NUM>, <NUM> is now explained with reference to <FIG> and the depicted connection between first coupling element <NUM> and bracket <NUM>. It has to be understood that the connection between second coupling element <NUM> and bracket <NUM> is established correspondingly. Eyelet <NUM> provides an opening that is narrower than the width of retaining portion 116b defined by opposing locking lugs 152a, 152b. As depicted in <FIG>, locking lugs 152a, 152b are connected only to a respective prong 150a, 150b, while being separated from extension portion 122b by a respective slit 151a. Locking lugs 150a, 150b of retaining portion 116b are therefore configured to be elastically urged toward one another. As explained above, each of locking lugs 152a, 152b is generally arrow-shaped. For threading first pin <NUM> into eyelet <NUM> of bracket <NUM>, chamfered front ends 153a, 153b of arrow-shaped locking lugs 152a, 152b are configured to elastically urge the pair of locking lugs 152a, 152b toward one another so that the tips of locking lugs 152a, 152b can pass through eyelet <NUM>. Locking lugs 152a, 152b are configured to snap back in their undeformed configuration once the tip portions have passed through eyelet <NUM>. The arrow-shaped locking lugs 152a, 152b are configured to engage the respective indents <NUM>, <NUM>. As discussed above, indents <NUM>, <NUM> are optional and can provide further safety against unintended separation of flowmeter <NUM> and valve assembly <NUM>. As depicted in <FIG>, back ends 155a, 155b are configured to engage with bracket <NUM> as depicted in <FIG>, and thereby prevent coupling element <NUM> from being unintentionally removed from eyelet <NUM>. Back ends 155a, 155b are preferably chamfered at an angle configured to allow toolless removal of coupling element <NUM> from bracket <NUM>, and thus of flowmeter <NUM> from valve assembly <NUM>. By virtue of back ends 155a, 155b engaging with bracket <NUM>, flowmeter <NUM> can potentially decreases the risk of unintended separation from valve assembly <NUM>, even if inlet valve V is subject to intense vibrations.

The symmetric arrangement of brackets <NUM>, <NUM> on annular outer surface <NUM> allows to insert coupling elements <NUM>, <NUM> into the respective eyelet from either side of brackets <NUM>, <NUM>. Thereby, in the preferred embodiment, flowmeter <NUM> can be selectively attached to valve assembly <NUM> in either one of a first and a second orientation. The first orientation is depicted in <FIG>, <FIG> and <FIG>, the second orientation is depicted in <FIG>, <FIG>, <FIG> and <FIG>. In <FIG>, an orientation of flowmeter <NUM> with respect to valve assembly <NUM> is defined by an orientation of the axis of symmetry of flowmeter <NUM> in a plane perpendicular to a flow axis of fluid path <NUM> that extends coaxially through and is enclosed by wall section <NUM>. This plane coincides with a plane of rotation of an impeller <NUM>, which will be described later. As can be inferred from the comparison of <FIG>, <FIG> and <FIG> with <FIG>, <FIG>, <FIG> and <FIG> the first and second orientation are spaced from each other at a <NUM>° separation in this plane. In other preferred embodiments, inlet valve V is configured such that flowmeter <NUM> can be selectively attached to valve assembly in more than two orientations. In a particularly preferred embodiment, valve assembly <NUM> comprises two pairs of brackets, i.e. four brackets, evenly spaced around annular outer surface <NUM>. In such embodiments, flowmeter <NUM> is configured such that first and second coupling element <NUM>, <NUM> can be selectively coupled either one of the pairs of brackets. In other words, in such embodiments, flowmeter <NUM> is selectively attachable to valve assembly <NUM> in either one of a first, a second, a third and a fourth orientation. By adapting the number and spacing of brackets spaced around annular outer surface <NUM>, the number of available orientations can be chosen as desired. A potential advantage of being able to choose from different orientations when attaching flowmeter <NUM> is readily apparent from <FIG> and <FIG>. Inlet valve V may be adapted to the packaging constraints of different washing machine by arranging flowmeter <NUM> in a suitable orientation, in particular by choosing the orientation of connection portion <NUM>. Thus, inlet valve V is not limited to use in a particular type of washing machine but may be employed over different types and series with only minor modifications, if any.

Now turning to <FIG>, <FIG> and <FIG>, valve assembly <NUM> comprises a flow rate indicator <NUM> configured to provide a quantity indicative of the fluid flow rate through fluid path <NUM>. In the embodiment of <FIG>, flow rate indicator <NUM> comprises an impeller <NUM> placed in flow path <NUM> perpendicular to the direction of the fluid flow. A first magnet <NUM> and a second magnet <NUM> are arranged on opposing vanes of impeller <NUM>. By virtue of the attachment of coupling portion <NUM> to counter-coupling portion <NUM>, flowmeter <NUM> is positioned such that sensor <NUM> lies in the plane of rotation of impeller <NUM> and thus magnets <NUM>, <NUM>. Sensor <NUM> in the depicted embodiment is a hall sensor, detecting a magnetic field of magnets <NUM>, <NUM> passing underneath sensor <NUM> to determine the rotation rate of impeller <NUM>, and thus allow circuitry <NUM> and/or the control unit of the washing machine to determine the fluid flow rate in fluid path <NUM>. In other words, the detectable quantity in the depicted embodiment is a magnetic field.

For reliably detecting a magnetic field, hall sensors require to be placed at a particular distance relative to the source of the magnetic field, i.e. magnets <NUM>, <NUM> of impeller <NUM>. As depicted for example in <FIG>, <FIG> and <FIG>, mating surface <NUM> of housing <NUM> is in contact with abutting surface <NUM>. The wall thickness of housing <NUM> at mating surface <NUM> and the wall thickness of section <NUM> at abutting surface <NUM> spaces sensor <NUM> at a predetermined distance from impeller <NUM>. In preferred embodiments, coupling portion <NUM> is configured to bias mating surface <NUM> against abutting surface <NUM>. In the particularly preferred embodiment of <FIG>, the dimensions of coupling elements <NUM>, <NUM> is chosen such that, when flowmeter <NUM> is attached to valve assembly <NUM>, a pulling force is exerted by locking lugs 152a, 152b, 154a, 154b so as to press mating surface <NUM> against abutting surface <NUM>. In particularly preferred embodiments, the pulling force is a result of elastic stretching of coupling elements <NUM>, <NUM>. Thereby, the risk that mating surface <NUM> separates from abutting surface <NUM>, thereby increasing the distance of sensor <NUM> to impeller <NUM> and thus magnets <NUM>, <NUM> can be reduced, even under increased vibrational loading. In other words, the present invention may increase the reliability of the flow rate measurement, since the predetermined distance is maintained with increased probability. The predetermined distance is chosen according to the type of magnet used. In some embodiments, the predetermined distance is configured for use of ferrite magnets. In other embodiments, the predetermined distance is configured for use of rare earth metal magnets, such as neodymium magnets. In particularly preferred embodiments, the predetermined distance is a mean value between a predetermined distance for ferrite magnets and a predetermined distance for rare earth metal magnets, such as neodymium magnets. Thus, the present invention may be used with rare earth metal magnets, such as neodymium magnets, as well as ferrite magnets without having to change the dimensions of either flowmeter <NUM> or valve assembly <NUM>.

Claim 1:
Flowmeter (<NUM>) for determining a fluid flow rate through an associated valve assembly (<NUM>), the flowmeter (<NUM>) being an entity separate from and removably attachable to the associated valve assembly (<NUM>), comprising:
a housing (<NUM>);
a sensor arrangement (<NUM>) disposed in the housing (<NUM>), the sensor arrangement (<NUM>) comprising at least one sensor (<NUM>) configured to detect a quantity provided by a flow rate indicator (<NUM>) of the valve assembly (<NUM>), the quantity being indicative of the fluid flow rate through a fluid path (<NUM>) of the valve assembly (<NUM>); and
a coupling portion (<NUM>) provided at the housing (<NUM>) and configured to couple with an associated counter-coupling portion (<NUM>) of the valve assembly (<NUM>) for attaching the flowmeter (<NUM>) to the valve assembly (<NUM>) in an orientation with respect to the valve assembly (<NUM>) selectable from a group comprising at least a first orientation and a second orientation.