Electromagnetically actuated fluidic valves and switches

The absence of high efficiency, compact fluidic pumps has until recently blocked the consideration of using hydraulic devices within portable and/or alkaline battery powered consumer and non-consumer products. The higher the functionality and programmability desired for a consumer and/or non-consumer product exploiting a fluidic pump then the more complex the overall fluidic system in terms of the number of actuators, valves, switches etc. within the fluidic system coupled to the one or more fluidic pumps. Accordingly, there exists a requirement to provide compact fluidic valves and switches to support configurability, programmability, and operation of these portable battery-operated consumer and non-consumer devices in conjunction with these newly available high efficiency, compact fluidic pumps. Such fluidic valves and switches should offer high efficiency, have a small footprint, be low complexity for high reliability and ease of manufacture, and low cost.

Not Applicable.

FIELD OF THE INVENTION

The present invention relates to fluidic valves and switches and more particularly to fluidic valves and switches for consumer and non-consumer applications offering high efficiency, small footprint, low complexity and low cost.

BACKGROUND OF THE INVENTION

Within a wide range of consumer and non-consumer products there are requirements for a range of different actuators which are controlled from one or more motors either directly or via switches etc. Within many instances their applications are limited by the availability of compact, low cost motors to provide distributed power for motion generation and/or pressure generation. In comparison to other techniques fluidics offers an efficient means of distributing power to activate elements remote from the power source as the pressure/fluid flow may be used directly to generate pressure and/or motion without requiring an additional transducer, e.g. a motor to convert electric power to mechanical power. Accordingly, fluidics may allow either air and/or liquid based fluidic devices to be provided which are suitable for applications in these consumer and non-consumer products that are compatible with the dimensions, design, and performance required whilst also operating multiple actuators of one or more types and allowing multiple motors (pumps) to be employed within a small region. Further, fluidic actuators may be flexed and/or distorted during operation as well as operating after having been flexed and/or distorted.

Today fluidic developments are primarily within the realm of micro-fluidics for self-powered biological and/or chemical testing applications where dimensions are measured in micrometers (microinches) or pump based hydraulic (fluidic) systems for plumbing, refrigeration, heating, hydroculture, vehicle suspensions, etc. where dimensions are measured in centimeters (inches). Such pump based systems exploit pumps such as rotary vane pumps, diaphragm pumps, gear pumps etc. which are bulky, low efficiency, and high power requiring connection to the electrical power grid (mains electricity) or other power sources such as lead acid batteries or petrol/diesel/gas engines. The absence of high efficiency, compact fluidic pumps has until recently blocked the consideration of using hydraulic devices within portable and/or alkaline battery powered consumer and non-consumer products. Further, most prior art pumps do not support the operation modes required for such devices, such as, for example, low frequency, variable duration, and pulsed for those providing primary pumps for dimensional adjustments or for example, high frequency operation for those providing secondary pumps for vibration and other types of motion/excitation.

In contrast, electromagnetic pumps offer a low power, compact, linear fluidic pump solution as evident from those developed by the inventor and described within WO/2014/047717 entitled “Methods and Devices for Fluidic Driven Adult Devices” and WO/2014/047718 entitled “Fluidic Methods and Devices.” Such electromagnetic pumps can achieve sufficient efficiency to enable their deployment within portable battery powered consumer and non-consumer products employing fluidics such as those, for example, described by the inventor within the preceding publications and WO/2015/135,070 entitled “Methods and Devices to Hydraulic Consumer Devices.” The entire contents of WO/2014/047,717; WO/2914/047,718; and WO/2015/135,070 being incorporated herein by reference.

However, the higher the functionality and programmability desired for the consumer and/or non-consumer product then the more complex the overall fluidic system in terms of the number of actuators, valves, switches etc. within the fluidic system coupled to the one or more fluidic pumps. It would therefore be beneficial to be provide fluidic valves and switches to support configurability, programmability, and operation of these portable battery-operated consumer and non-consumer devices. Accordingly, such fluidic valves and switches should offer high efficiency, have a small footprint, be low complexity for high reliability and ease of manufacture, and low cost.

SUMMARY OF THE INVENTION

It is an object of the present invention to mitigate limitations within the prior art relating to fluidic valves and switches and more particularly to fluidic valves and switches for consumer and non-consumer applications offering high efficiency, small footprint, low complexity and low cost.

In accordance with an embodiment of the invention there is provided a fluidic device comprising:a piston comprising at least a core formed from a first magnetic material having a first length and a first predetermined lateral dimension;a piston sleeve formed from a first predetermined non-magnetic material having an inner bore having a predetermined tolerance with respect to the first predetermined lateral dimension of the piston, an outer profile of a second predetermined lateral dimension, and a second length;at least an electrical coil of a plurality of electrical coils, each electrical coil with an inner bore having a predetermined tolerance with respect to the second predetermined lateral dimension, a fourth length, and disposed at a predetermined position relative to the piston sleeve in dependence upon at least the lengths of the piston sleeve and piston;a pair of magnetic washers formed from a second predetermined magnetic material each having a second thickness and having a central opening, wherein each magnetic washer is disposed at one end of the piston sleeve; anda pair of non-magnetic washers formed from at least a third predetermined non-magnetic material having an outer portion, an inner portion, and comprising a pair of openings through at least the outer portion of the non-magnetic washer, wherein the pair of openings are disposed either side of a radial axis of the non-magnetic washer and each non-magnetic washer is disposed externally to one of the magnetic washers such that a surface of the outer portion is in contact with the magnetic washer and the inner portion projects through the magnetic washer towards the middle of the piston sleeve and limits motion of the piston within the piston sleeve;whereinin a first configuration the piston is retained against the inner portion of the non-magnetic washer at one end of the piston sleeve by magnetic attraction to the magnetic washer at that end of the piston sleeve thereby blocking fluid flow through the pair of openings at that end of the piston sleeve but allowing fluid flow through the pair of openings at the other distal end of the piston sleeve;in a second configuration the piston is retained against the inner portion of the non-magnetic washer at the other distal end of the piston sleeve by magnetic attraction to the magnetic washer at that distal end of the piston sleeve thereby blocking fluid flow through the pair of openings at that distal end of the piston sleeve but allowing fluid flow through the pair of openings via at the other end of the piston sleeve; andthe piston is moved to establish either of the first configuration and the second configuration by selective electrical excitation of the at least one electrical coil of the plurality of electrical coils.

In accordance with an embodiment of the invention there is provided a fluidic device comprising:a piston having a first length and a first predetermined lateral dimension comprising a core formed from a first magnetic material and a pair of end caps formed from a first predetermined non-magnetic material;a piston sleeve formed from a first predetermined non-magnetic material having an inner bore having a predetermined tolerance with respect to the first predetermined lateral dimension of the piston, an outer profile of a second predetermined lateral dimension, and a second length;at least an electrical coil of a plurality of electrical coils, each electrical coil with an inner bore having a predetermined tolerance with respect to the second predetermined lateral dimension, a fourth length, and disposed at a predetermined position relative to the piston sleeve in dependence upon at least the lengths of the piston sleeve and piston;a pair of magnetic washers formed from a second predetermined magnetic material each having a second thickness and having a central opening, wherein each magnetic washer is disposed at one end of the piston sleeve; anda pair of non-magnetic washers formed from at least a second predetermined non-magnetic material having an outer portion, an inner portion, and comprising a pair of openings through at least the outer portion of the non-magnetic washer, wherein the pair of openings are disposed either side of a radial axis of the non-magnetic washer and each non-magnetic washer is disposed externally to one of the magnetic washers such that a surface of the outer portion is in contact with the magnetic washer and the inner portion projects through the magnetic washer towards the middle of the piston sleeve and limits motion of the piston within the piston sleeve;whereinin a first configuration the piston is retained against the inner portion of the non-magnetic washer at one end of the piston sleeve by magnetic attraction to the magnetic washer at that end of the piston sleeve thereby blocking fluid flow through the pair of openings at that end of the piston sleeve but allowing fluid flow through the pair of openings at the other distal end of the piston sleeve;in a second configuration the piston is retained against the inner portion of the non-magnetic washer at the other distal end of the piston sleeve by magnetic attraction to the magnetic washer at that distal end of the piston sleeve thereby blocking fluid flow through the pair of openings at that distal end of the piston sleeve but allowing fluid flow through the pair of openings via at the other end of the piston sleeve; andthe piston is moved to establish either of the first configuration and the second configuration by selective electrical excitation of the at least one electrical coil of the plurality of electrical coils.

In accordance with an embodiment of the invention there is provided a fluidic device comprising:a piston comprising at least a core formed from a first magnetic material having a first length and a first predetermined lateral dimension;a piston sleeve formed from a first predetermined non-magnetic material having an inner bore having a predetermined tolerance with respect to the first predetermined lateral dimension of the piston, an outer profile of a second predetermined lateral dimension, and a second length;at least an electrical coil of a plurality of electrical coils, each electrical coil with an inner bore having a predetermined tolerance with respect to the second predetermined lateral dimension, a fourth length, and disposed at a predetermined position relative to the piston sleeve in dependence upon at least the lengths of the piston sleeve and piston;a pair of magnetic washers formed from a second predetermined magnetic material each having a second thickness and having a central opening, wherein each magnetic washer is disposed at one end of the piston sleeve;a first body disposed at one end of the piston sleeve formed from at least a third predetermined non-magnetic material having an outer portion, an inner portion, and defining a pair of openings through at least the outer portion of the non-magnetic washer, wherein the pair of openings are disposed either side of a radial axis of the piston sleeve, the outer portion has a first surface disposed towards the external surface of the magnetic washer at that end of the piston sleeve, and the inner portion projects through the magnetic washer towards the middle of the piston sleeve and limits motion of the piston within the piston sleeve; anda second body disposed at the other end of the piston sleeve formed from at least a fourth predetermined non-magnetic material having an outer portion, an inner portion, and defining a pair of openings through at least the outer portion of the non-magnetic washer, wherein the pair of openings are disposed either side of a radial axis of the piston sleeve, the outer portion has a first surface disposed towards the external surface of the magnetic washer at that end of the piston sleeve, and the inner portion projects through the magnetic washer towards the middle of the piston sleeve and limits motion of the piston within the piston sleeve;whereinin a first configuration the piston is retained against the inner portion of the non-magnetic washer at one end of the piston sleeve by magnetic attraction to the magnetic washer at that end of the piston sleeve thereby blocking fluid flow through the pair of openings at that end of the piston sleeve but allowing fluid flow through the pair of openings at the other distal end of the piston sleeve;in a second configuration the piston is retained against the inner portion of the non-magnetic washer at the other distal end of the piston sleeve by magnetic attraction to the magnetic washer at that distal end of the piston sleeve thereby blocking fluid flow through the pair of openings at that distal end of the piston sleeve but allowing fluid flow through the pair of openings via at the other end of the piston sleeve;the piston is moved to establish either of the first configuration and the second configuration by selective electrical excitation of the at least one electrical coil of the plurality of electrical coils; andthe first body and second body provide at least one of fluidic channels through which fluid flows to and from the openings at either end of the fluidic device and part of at least one of a scaffold and casing of a device of which the fluidic device forms part.

DETAILED DESCRIPTION

The present invention is directed to fluidic motors and pumps and more particularly to fluidic valves and switches and more particularly to fluidic valves and switches for consumer and non-consumer applications offering high efficiency, small footprint, low complexity and low cost.

The ensuing description provides representative embodiment(s) only, and is not intended to limit the scope, applicability or configuration of the disclosure. Rather, the ensuing description of the embodiment(s) will provide those skilled in the art with an enabling description for implementing an embodiment or embodiments of the invention. It being understood that various changes can be made in the function and arrangement of elements without departing from the spirit and scope as set forth in the appended claims. Accordingly, an embodiment is an example or implementation of the inventions and not the sole implementation. Various appearances of “one embodiment,” “an embodiment” or “some embodiments” do not necessarily all refer to the same embodiments. Although various features of the invention may be described in the context of a single embodiment, the features may also be provided separately or in any suitable combination. Conversely, although the invention may be described herein in the context of separate embodiments for clarity, the invention can also be implemented in a single embodiment or any combination of embodiments.

Reference in the specification to “one embodiment”, “an embodiment”, “some embodiments” or “other embodiments” means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least one embodiment, but not necessarily all embodiments, of the inventions. The phraseology and terminology employed herein is not to be construed as limiting but is for descriptive purpose only. It is to be understood that where the claims or specification refer to “a” or “an” element, such reference is not to be construed as there being only one of that element. It is to be understood that where the specification states that a component feature, structure, or characteristic “may”, “might”, “can” or “could” be included, that particular component, feature, structure, or characteristic is not required to be included.

Reference to terms such as “left”, “right”, “top”, “bottom”, “front” and “back” are intended for use in respect to the orientation of the particular feature, structure, or element within the figures depicting embodiments of the invention. It would be evident that such directional terminology with respect to the actual use of a device has no specific meaning as the device can be employed in a multiplicity of orientations by the user or users.

Reference to terms “including”, “comprising”, “consisting” and grammatical variants thereof do not preclude the addition of one or more components, features, steps, integers or groups thereof and that the terms are not to be construed as specifying components, features, steps or integers. Likewise, the phrase “consisting essentially of”, and grammatical variants thereof, when used herein is not to be construed as excluding additional components, steps, features integers or groups thereof but rather that the additional features, integers, steps, components or groups thereof do not materially alter the basic and novel characteristics of the claimed composition, device or method. If the specification or claims refer to “an additional” element, that does not preclude there being more than one of the additional element.

A “scaffold” or “scaffolds” as used herein, and throughout this disclosure, refers to a structure that is used to hold up, interface with, or support another material or element(s). This includes, but is not limited to, such two-dimensional (2D) structures such as substrates and films, three-dimensional (3D) structures such as geometrical objects, non-geometrical objects, combinations of geometrical and non-geometrical objects, naturally occurring structural configurations, and manmade structural configurations. A scaffold may be solid, hollow, and porous or a combination thereof. A scaffold may contain recesses, pores, openings, holes, vias, and channels or a combination thereof. A scaffold may be smooth, textured, have predetermined surface profiles and/or features. A scaffold may be intended to support one or more other materials, one or more films, a multilayer film, one type of particle, multiple types of particles etc. A scaffold may include, but not be limited to, a spine of a device and/or a framework, for example, which also supports a shell and/or a casing.

A “shell” as used herein, and throughout this disclosure, refers to a structure that is used to contain and/or surround at least partially and/or fully a number of elements within adult devices according to embodiments of the invention. A shell may include, but not limited to, a part or parts that are mounted to a scaffold or scaffolds that support elements within a device according to an embodiment of the invention.

A “casing” as used herein, and throughout this disclosure, refers to a structure surrounding a scaffold and/or shell. This includes structures typically formed from an elastomer and/or silicone to provide a desired combination of physical tactile surface properties to the device it forms part of and other properties including, but not limited to, hermeticity, liquid ingress barrier, solid particulate ingress barrier, surface sheen, and colour. A casing may include, but not limited to, a part or parts that are mounted to a scaffold or scaffolds and/or a casing or casings forming part of a device according to an embodiment of the invention.

A “plastic” as used herein, and throughout this disclosure, refers to a synthetic or semi-synthetic organic compound which may include, but are not limited to, one or more polyesters, one or more thermoplastics, one or more thermosetting polymers, one or more elastomers, and one or more silicones. A plastic may exploit the one or more materials discretely or in combination with one or more materials to adjust the plastics physical properties such as graphite fibers, aramid fibers, etc.

A “polyester” as used herein, and throughout this disclosure, refers to a category of polymers that contain the ester functional group in their main chain. This includes, but is not limited to polyesters which are naturally occurring chemicals as well as synthetics through step-growth polymerization, for example. Polyesters may be biodegradable or not. Polyesters may be a thermoplastic or thermoset or resins cured by hardeners. Polyesters may be aliphatic, semi-aromatic or aromatic. Polyesters may include, but not be limited to, those exploiting polyglycolide, polylactic acid (PLA), polycaprolactone (PCL), polyhydroxyalkanoate (PHA), polyhydroxybutyrate (PHB), polyethylene adipate (PEA), polybutylene succinate (PBS), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), and polyethylene naphthalate (PEN).

A “thermoplastic” or “thermosoftening plastic” as used herein and throughout this disclosure, refers to a category of polymers that become pliable or moldable above a specific temperature and solidify upon cooling. Thermoplastics may include, but not be limited, polycarbonate (PC), polyether sulfone (PES), polyether ether ketone (PEEK), polyethylene (PE), polypropylene (PP), poly vinyl chloride (PVC), polytetrafluoroethylene (PTFE), polyimide (PI), polyphenylsulfone (PPSU), polychlorotrifluoroethene (PCTFE or PTFCE), florinated ethylene propylene (FEP), and perfluoroalkoxy alkane (PFA).

A “metal” as used herein, and throughout this disclosure, refers to a material that has good electrical and thermal conductivity. Such materials may be malleable and/or fusible and/or ductile. Metals may include, but not be limited to, aluminum, nickel, copper, cobalt, chromium, silver, gold, platinum, iron, zinc, titanium, and alloys thereof such as bronze, stainless steel, stainless steel, brass, and phosphor bronze.

An “aramid” as used herein, and throughout this disclosure, refers to an aromatic polyamide. Aramids are a class of materials fibers in which the chain molecules are highly oriented along the fiber axis, so the strength of the chemical bond can be exploited. Examples, include, but are not limited to fibers distributed under brand names such as Kevlar™, Technora™, Twaron™, Heracron™, Nomex™, Innegra S™ and Vectran™ as well as nylon and ultra-high molecular weight polyethylene.

A “silicone” as used herein, and throughout this disclosure, refers to a polymer that includes any inert, synthetic compound made up of repeating units of siloxane.

An “elastomeric” material or “elastomer” as used herein, and throughout this disclosure, refers to a material, generally a polymer, with viscoelasticity. Elastomers may include, but not be limited to, unsaturated rubbers such as polyisoprene, butyl rubber, ethylene propylene rubber, silicone rubber, fluorosilicone rubber, fluoroelastomers, perfluoroelastomers, and thermoplastic elastomers.

“Rubber” as used herein, and throughout this disclosure, refers to either natural rubber comprising poly-cis-isoprene or “synthetic rubber” which refers to a subset of elastomers made from various petroleum-based monomers. Synthetic rubbers may include styrene-butadiene rubbers (SBR) derived from the copolymerization of styrene and 1,3-butadiene or other synthetic rubbers prepared from isoprene (2-methyl-1,3-butadiene), chloroprene (2-chloro-1,3-butadiene), and isobutylene (methylpropene) with a small percentage of isoprene for cross-linking.

“Elastic modulus” (also known as modulus of elasticity) as used herein, and throughout this disclosure, refers to a material's resistance to being deformed elastically (i.e., non-permanently) when a stress is applied to it. The elastic modulus of a material is defined as the slope of its stress-strain curve within its elastic deformation region. Stiffer materials will have a higher elastic modulus. The three primary elastic moduli are Young's modulus, which describes a material's tensile elasticity; shear modulus or modulus of rigidity which describes a material's tendency to shear; bulk modulus which describes a material's volumetric elasticity; as well as Poisson's ratio, Lame's first parameter, and P-wave modulus.

A “magnet” as used herein, and throughout this disclosure, refers to material or object that produces a magnetic field which is made from a material that is magnetized and creates its own persistent magnetic material.

A “magnetic material” as used herein, and throughout this disclosure, refers to a material that is magnetized and creates its own persistent magnetic material. These may be magnetically soft materials which can be magnetised but do not tend to stay magnetised or magnetically hard materials which do stay magnetised. Such magnetic materials may include, but are not limited to, a ferromagnetic material such as iron; nickel; cobalt; ferrite; alnico, a family of iron alloys composed primarily of aluminium (Al), nickel (Ni), and cobalt (Co) but may also include copper (Cu) and titanium (Ti); some alloys of rare-earth metals such as those based around neodymium (e.g. Nd2Fe14B), samarium-cobalt (e.g. SmCo5and Sm(Co,Fe,Cu,Zr)7, and strontium-ferrite (Sr-ferrite).

A “piston” as used herein, and throughout this disclosure, refers to an axial permanent magnet having a predetermined cross-section intend to fit within and move within a sleeve, i.e. piston sleeve. The piston may be formed solely from a permanent magnetic material such as AlNiCo or neodymium for example. Alternatively, it may be formed from a pair of permanent magnetic material end “washers” and a central body of iron for example or a pair of permanent magnetic axial elements.

A “fluidic device” or “fluidic system” as used herein, and throughout this disclosure, refers to a fluidic device, sub-system or system exploiting fluidics for motion and/or actuation at least in part. A fluidic device may be discrete or combined with other elements/devices/systems/sub-systems to provide one or more functions within a consumer or non-consumer device/system/sub-system. Such devices may, for example, be partially or wholly inserted within an orifice of the human body; attached and/or mounted to engage a specific region or portion of the user's body; worn by the user including those under, within, with or on top of clothing; mounted upon a surface and/or object allowing interaction with a user; be interactive with a user or users; and provide discrete and/or combined functions independent of the presence or absence of a user; and be part of mobile and/or non-mobile robotic systems. Such fluidic devices may be functional, aesthetic, therapeutic, non-medical, and medical (e.g. drug delivery systems, medical testing and diagnosis devices).

An “opening” or “inlet port” or “outlet port” as used herein, and throughout this disclosure, refers to a channel through one or more elements forming part of a device or assembly according to an embodiment of the invention through which fluid can flow.

Within the following description with respect to embodiments of the invention described in respect ofFIGS. 1 to 19Ba material may be referred to as being “hard.” A “hard” material being one having a high elastic modulus, i.e. a high force per unit area is needed to achieve a given amount of distortion. Within the following description with respect to embodiments of the invention described in respect ofFIGS. 1 to 19Ba material defined as being “soft.” A “soft” material being one having a low elastic modulus, i.e. a low force per unit area is needed to achieve a given amount of distortion. This elastic modulus typically being the material's Young's modulus which describes tensile elasticity, or the tendency of an object to deform along an axis when opposing forces are applied along that axis or alternatively the material's bulk modulus which describes volumetric elasticity, or the tendency of an object to deform in all directions when uniformly loaded in all directions. The bulk modulus is an extension of Young's modulus to three dimensions and is the inverse of a materials compressibility.

It would be appreciated by one of skill in the art that the terms “hard” and “soft” are relative in that, for example, plastic is hard relative to an elastomer but is soft relative to steel. Accordingly, the terms are not intended to limit the materials employed in providing interfaces that come into contact with one being “hard” and the other “soft.”

Within the following description for the sake of providing references associated with embodiments of the invention references are made to a particular product category or product, e.g. massagers, toys, robotic systems, adult toys etc., however such associations are purely for sake of improving the reader's understanding of the embodiments of the invention and are not intended to limit or define the applications of the different aspects of the invention and embodiments of the invention.

ELECTROMAGNETIC VALVES/SWITCHES: Referring toFIG. 1there is depicted a perspective view of a fluidic consumer device in first image100A which comprises an electromagnetic pump (ELPUMP) coupled to a fluid reservoir and therein via a fluidic switch module to a plurality of fluidic actuators that provide for functionality and user configurability of the fluidic consumer device100A. Such functionality and user configurability including, but not limited to, dimensional adjustments such as length, diameter etc.; geometrical adjustments such as rotation, flex, etc.; and actuation such as high frequency vibration, low frequency vibration, etc. The ELPUMP, reservoir, fluidic switch module etc. are within a scaffold, depicted in second image100B, which may “skinned” with one or more casings and/or shells typically formed from one or more plastic materials and/or elastomeric materials as depicted in first image100A. An example of a fluidic valve/switch module providing programmable control of the fluid within the fluidic actuators is depicted in third image100C ofFIG. 1. The fluidic valve/switch module comprising a fluidic valve/switch assembly (FVSMA)120disposed between an inlet manifold110, and outlet manifold130formed from manifold plate130A and manifold cap130B. As depicted the FVSMA120gas three linear magnetic moveable core (LMMC) fluidic valve/switch elements (FVSEs)125. According to the product, the functionality of the product, the configurability of the product etc. the number of LMMC-FVSEs within the FVSMA may vary. Each LMMC-FVSE125may be coupled to one or more fluidic actuators and driven under control of a control circuit to provide the desired fill/empty of the fluidic actuators for low frequency variations such as dimensions, geometric etc. as well as modulation for vibration etc. Optionally, the product may contain multiple FVSMAs coupled to a single ELPUMP or it may contain multiple FVSAMs coupled to multiple ELPUMPs where the number of LMMC-FVSEs within each FVSAM may be the same or vary.

Referring toFIG. 2there are depicted first and second perspective views200A and200B of the FVSAM120depicted in third image100C ofFIG. 1. Accordingly, the FVSAM comprises first to third LMMC-FVSE220A,220B and220C which are disposed between a first sheet210of valve stop elements and a second sheet230of valve stop elements. Each of the first to third LMMC-FVSE220A,220B and220C having an electrical connector240for receiving the electrical drive signals that actuate the motion of the magnetic piston with each of the first to third LMMC-FVSE220A,220B and220C through energising one or other of a pair of coils surrounding a sleeve within which the piston moves. Movement of a piston within an FVSE to either the end of the FVSE with the first sheet210of valve stop elements or the second sheet230of the valve stop elements results in the piston no longer blocking the openings with the second sheet230of valve stop elements or the first sheet210of the valve stop elements and therein opening that valve or switch. Accordingly, the elements of an FVSE such as those depicted inFIG. 2are depicted withinFIG. 3with first and second cross-sectional perspective images300A and300B respectively as:First sheet310of first gate valve stop elements;Second sheet330of second gate valve stop elements;First magnetic washer340;Second magnetic washer350;First coil360;Second coil370;Piston380, which is magnet, i.e. formed from a permanent magnetic material such as a “hard” ferromagnetic material for example;Inner sleeve390, formed from a non-magnetic material; andOuter sleeve395, formed from a magnetic material.

Accordingly, the piston when engaged against the first valve stop element315on the first sheet310blocks fluid flow between the first port300C and second port300D but fluid flow now can occur between third port300E and fourth port300F. When the piston is engaged against the second valve stop element335on the second sheet330fluid flow between the third port300E and fourth port300F but fluid flow now can occur between first port300C and second port300D. If the piston380is formed from a magnetic material, then when the piston is driven to the first valve stop element315to block fluid flow between the first port300C and second port300D the piston380is retained in position when the coil(s) are not energised by the first magnetic washer340. Similarly, when the piston is driven to the second valve stop element335to block fluid flow between the third port300E and fourth port300F the piston380is retained in position when the coil(s) are not energised by the second magnetic washer350. Accordingly, power consumption is minimised as the magnetic washers retain the piston in position until their retentive magnetic force is overcome by the magnetic force on the piston380generated by the first and/or second coils360and370respectively.

The first and second coils360and370respectively are energised such that the coils as depicted end to end have their outer faces having the same pole (e.g. north or south) and hence their inner faces the same opposite poles (e.g. south or north). The magnet is axially magnetized, i.e. north at one end and south at the other. Within embodiments of the invention the first and second coils360and370respectively can be energized at the same time, e.g. they are wired in series or parallel and excited by the same electrical source or controlled separately with precise phase or lag timed with respect to each other and the time required for magnet piston to go from one end to the other. It would be evident that precise timing and magnetic power of each coil, along with the current pulse shape or waveform, that efficiency of the electrical drive may be improved.

It would also be evident that too high a magnetic force applied to the magnetic piston can cause the magnet to bounce off the receiving end and therefore not latch against that end such that the switch or valve fails. However, with too small a magnetic force applied to the magnetic piston then the magnet may fail to reach the end against the fluid pressure and similarly not latch and therefore the switch or valve again fails. Accordingly, within embodiments of the invention sufficient magnetic force is applied to the magnet with a first electrical pulse applied to the coils to ensure that it reaches from one end to the other but once the piston has arrived at the other end a second short electrical pulse is applied to ensure that the piston is latched and stable at the far end.

As evident in first and second images300A and300B respectively each of the first valve stop element315and the second valve stop element335project through the respective one of the first magnetic washer340and second magnetic washer350. Now referring toFIG. 4there are depicted first and second images400A and400B respectively depicting a cross-sectional view and an exploded perspective view of a LMMC-FVSE as employed within the FVSAM120depicted inFIG. 2exploiting gate valve stop elements according to an embodiment of the invention disposed at either end of the LMMC-FVSE. As evident in first image400A the first valve stop element315of first sheet310projects through the opening of the first magnetic washer340to a distance l1whilst the second valve stop element335of the second sheet330projects through the opening of the second magnetic washer350to a distance l2. The magnetic retention of the magnetic piston380to either the first magnetic washer340or second magnetic washer350is determined by the magnetic strength of the piston380, the magnetic strength of either the first magnetic washer340or second magnetic washer350, and either the respective first distance l1or second distance l2. The larger the distance between end of the valve stop element which abuts the end face of the piston380and the magnetic washer then the lower the magnetic retention force and the lower the reverse magnetic force required to move the piston in the reverse direction. The lower the reverse magnetic force the lower the electrical power consumption required to reverse the FVSE from closed for that pair of openings to open.

The magnetic retentive force required for maintaining the piston in the position to close the fluidic connection between the openings at an end of a FVSE is dependent upon the fluidic pressure at that point in the fluidic system. Within many fluidic systems such as where the FVSE couples fluid from a reservoir under pressure with pressure flow generated by an ELPUMP to an actuator on one side and from the actuator to a reservoir at lower pressure from which the ELPUMP draws. Accordingly, the fluid pressure on one side of the FVSE is different to that of the FVSE on the other side. If electrical power consumption of the device of which the fluidic system comprising the FVSE(s) is not limited such as a device pulling power from an electrical supply such as 120V, 240V mains electricity, then minimizing the electrical consumption of the FVSE may not be of concern. However, in portable device applications reducing power consumption is important for increasing the duration that the device can be used particularly where there are multiple FVSEs and they are required to open/close/modulate at increasing rates according to the operating mode of the device.

Accordingly, FVSEs according to embodiments of the invention allow for the respective distances l1and l2to be established differently on each side in dependence upon the pressure that the piston within the FSVE must hold off when closed. Additionally, the pressure being held off can be adjusted within a predetermined range established in dependence upon the magnetic strength of the piston and magnetic washer by changing the distance between the end of the gate valve element and the magnetic washer. Accordingly, with a FVSAM employing FVSEs then all FVSEs can be adjusted simultaneously by replacing the sheet of gate valve elements with a different sheet providing a different distance. Optionally, rather than each sheet of gate valve elements providing a common distance for each FVSE the sheet may be formed with different distances for each FVSE assembled to it.

Referring to second image400B inFIG. 4then the elements of a single FVSE450such as those depicted inFIG. 2with FVSE220A,220B and2200C are depicted in an exploded perspective view together with the first sheet310of stop valve elements and second sheet330of stop valve elements which provide the appropriate standoff distances for the piston380at either end of the FVSE450for all three FVSEs450with the FVSAM120depicted in third image100C inFIG. 1. Accordingly, the FVSE450comprises:First magnetic washer340;Second magnetic washer350;First coil360;Second coil370;Piston380;Inner sleeve390;Outer sleeve395; andElectrical connector410.

The inlet and outlet ports of the FVSE on one end are defined by the sheet of stop valve elements within the inner opening of the magnetic washer. As the sheets of gate valve elements and the magnetic washers are each on the outer end of the FVSE then adjusting the magnetic strength of one or both of the magnetic washers and the respective standoff distances l1and l2is simple and straight forward allowing the other elements of the dual coil FVSE to be assembled and employed within multiple products. Similarly, different geometries of first and second coils360and370may provide different levels of electromagnetic activation for the piston where stronger or weaker magnetic washers are employed.

Referring toFIG. 5and first and second images500A and500B respectively there are depicted cross-sectional assembled and partially exploded views of the FVSAM120module ofFIG. 1along the section line X-X with the elements removed from one LMMC-FVSE according to an embodiment of the invention apart from the gate valve stop elements and magnetic washers. Referring toFIG. 6and first and second images600A and600B respectively there are depicted cross-sectional views of assembled and partially exploded magnetic washers and sheets of gate valve elements of the FVSAM120module ofFIG. 1along the section line X-X according to an embodiment of the invention with all other elements removed.

Now referring toFIG. 7there are depicted the elements of an FVSE such as those depicted inFIG. 2within first and second cross-sectional perspective images700A and700B wherein the gate valve elements and their respective sheets at either end of the FVSAM and each FVSE have been replaced with block valves. Accordingly, the elements of each FVSE are:First sheet710of first block valve stop elements;Second sheet730of second block valve stop elements;First magnetic washer740;Second magnetic washer750;First coil760;Second coil770;Piston780;Inner sleeve790; andOuter sleeve795.

Accordingly, the piston now when engages against the first valve stop element715on the first sheet710and blocks fluid flow between the first port700C and second port700D but fluid flow now can occur between third port700E and fourth port700F. In contrast to the gate valves described and depicted in respect ofFIGS. 3 to 6where the gate valve fills the width of the bore of the inner shell that the piston moves within and the piston against the tip of the gate valve blocks fluid flow. Within the valve stop elements inFIGS. 7 to 10respectively there is no projecting tip and the piston engages against the outer ring of the valve element and the valve stop element.

When the piston is engaged against the second valve stop element735on the second sheet730fluid flow between the third port700E and fourth port700F but fluid flow now can occur between first port700C and second port700D. If the piston780is formed from a magnetic material, then when the piston is driven to the first valve stop element715to block fluid flow between the first port700C and second port700D the piston780is retained in position when the coil(s) are not energised by the first magnetic washer740. Similarly, when the piston is driven to the second valve stop element775to block fluid flow between the third port700E and fourth port700F the piston780is retained in position when the coil(s) are not energised by the second magnetic washer750. Accordingly, power consumption is minimised as the magnetic washers retain the piston in position until their retentive magnetic force is overcome by the magnetic force on the piston780generated by the first and/or second coils760and770respectively.

As evident in first and second images700A and700B respectively each of the first valve stop element715and the second valve stop element735project through the respective one of the first magnetic washer740and second magnetic washer750. Now referring toFIG. 8there are depicted first and second images800A and800B respectively depicting a cross-sectional view and an exploded perspective view of a LMMC-FVSE as employed within the FVSAM120depicted inFIG. 2exploiting gate valve stop elements according to an embodiment of the invention disposed at either end of the LMMC-FVSE. As evident in first image800A the first valve stop element715of first sheet710projects through the opening of the first magnetic washer740to a distance l1whilst the second valve stop element735of the second sheet730projects through the opening of the second magnetic washer750to a distance l2. The magnetic retention of the magnetic piston780to either the first magnetic washer740or second magnetic washer750is determined by the magnetic strength of the piston780, the magnetic strength of either the first magnetic washer740or second magnetic washer750, and either the respective first distance l1or second distance l2. The larger the distance between end of the valve stop element which abuts the end face of the piston780and the magnetic washer then the lower the magnetic retention force and the lower the reverse magnetic force required to move the piston in the reverse direction. The lower the reverse magnetic force the lower the electrical power consumption required to reverse the FVSE from closed for that pair of openings to open.

The magnetic retentive force required for maintaining the piston in the position to close the fluidic connection between the openings at an end of a FVSE is dependent upon the fluidic pressure at that point in the fluidic system. Within many fluidic systems such as where the FVSE couples fluid from a reservoir under pressure with pressure flow generated by an ELPUMP to an actuator on one side and from the actuator to a reservoir at lower pressure from which the ELPUMP draws. Accordingly, the fluid pressure on one side of the FVSE is different to that of the FVSE on the other side. If electrical power consumption of the device of which the fluidic system comprising the FVSE(s) is not limited such as a device pulling power from an electrical supply such as 120V, 240V mains electricity, then minimizing the electrical consumption of the FVSE may not be of concern. However, in portable device applications reducing power consumption is important for increasing the duration that the device can be used particularly where there are multiple FVSEs and they are required to open/close/modulate at increasing rates according to the operating mode of the device.

Accordingly, FVSEs according to embodiments of the invention allow for the respective distances l1and l2to be established differently on each side in dependence upon the pressure that the piston within the FSVE must hold off when closed. Additionally, the pressure being held off can be adjusted within a predetermined range established in dependence upon the magnetic strength of the piston and magnetic washer by changing the distance between the end of the gate valve element and the magnetic washer. Accordingly, with a FVSAM employing FVSEs then all FVSEs can be adjusted simultaneously by replacing the sheet of gate valve elements with a different sheet providing a different distance. Optionally, rather than each sheet of gate valve elements providing a common distance for each FVSE the sheet may be formed with different distances for each FVSE assembled to it.

Referring to second image800B inFIG. 8then the elements of a single FVSE850such as those depicted inFIG. 2with FVSE220A,220B and2200C are depicted in an exploded perspective view together with the first sheet710of stop valve elements and second sheet730of stop valve elements which provide the appropriate standoff distances for the piston780at either end of the FVSE850for all three FVSEs850with the FVSAM120depicted in third image100C inFIG. 1. Accordingly, the FVSE850comprises:First magnetic washer740;Second magnetic washer750;First coil760;Second coil770;Piston780;Inner sleeve790;Outer sleeve795; andElectrical connector410.

The inlet and outlet ports of the FVSE on one end are defined by the sheet of stop valve elements within the inner opening of the magnetic washer. As the sheets of gate valve elements and the magnetic washers are each on the outer end of the FVSE then adjusting the magnetic strength of one or both of the magnetic washers and the respective standoff distances l1and l2is simple and straight forward allowing the other elements of the dual coil FVSE to be assembled and employed within multiple products. Similarly, different geometries of first and second coils760and770may provide different levels of electromagnetic activation for the piston where stronger or weaker magnetic washers are employed.

Referring toFIG. 9and first and second images900A and900B respectively there are depicted cross-sectional assembled and partially exploded views of the FVSAM120module ofFIG. 1along the section line X-X with the elements removed from one LMMC-FVSE according to an embodiment of the invention apart from the gate valve stop elements and magnetic washers. Referring toFIG. 10and first and second images1000A and1000B respectively there are depicted cross-sectional views of assembled and partially exploded magnetic washers and sheets of gate valve elements of the FVSAM120module ofFIG. 1along the section line X-X according to an embodiment of the invention with all other elements removed.

Within the embodiments of the invention described and depicted in respect ofFIGS. 3 to 10respectively the piston is driven to one end or the other of the FVSE under action of a pair of annular coils, such as first coil360and second coil370inFIG. 3or first coil760and second coil770inFIG. 7. Alternatively, as depicted inFIG. 11in first and second images1100A and1100B the piston may be driven to either end under the action of a single coil. Within each of the first and second images1100A and1100B at one end of the FVSE is first valve sheet1120and first magnet1140whilst at the other end there are disposed second valve sheet1130and second magnet1150. Within first image1100A the coil is first coil1110which is disposed towards the same end as second sheet1130and second magnet1150whilst within second image1100B the coil is second coil1160disposed towards the end with first valve sheet1120and first magnet1140. In common with the FVSEs depicted inFIGS. 3 to 10respectively once driven to one end or the other the annular coil(s), e.g. first coil1110or second coil1160, may be de-energized as the magnetic attraction between the magnet, e.g. first magnet1140or second magnet1150maintains the piston in position.

The magnetic force may be adjusted lower/higher by increasing/decreasing the distance that the valve, inFIG. 11a gate valve, projects through the respective magnet(s). It would be evident that the same single coil FVSE as depicted inFIG. 11may be employed with block valves such as depicted inFIGS. 7 to 10respectively as opposed to the gate valves depicted inFIGS. 3 to 6respectively. Whilst the embodiments of the invention described and depicted in respect ofFIGS. 1 to 11respectively these provide a valve/switch at each end of the FVSE it would be evident that alternatively other embodiments of the invention may exploit a valve/switch at only one end.

Within the embodiments of the invention described above in respect ofFIGS. 1 to 11above the FVSE and FVSAM modules employing the FVSE(s) exploit either a gate valve or block valve which engages against the end face of a piston to close the valve/switch when the piston is driven against the gate valve or block valve and the valve/switch opens when the piston is driven away from the gate valve/block valve. Within embodiments of the invention the piston is formed from a magnetic material which is metal and accordingly hard. The sheets of gate valve stop elements such as first sheet310and second sheet330inFIGS. 3 to 6or sheets of valve stop elements such as first sheet710and second sheet730inFIGS. 7 to 10may typically be formed from a plastic. Accordingly, the plastic may be hard, or it may be soft.

Referring toFIG. 12Athere are depicted first to fourth images1200A to1200D. First and second images1200A and1200B depict a first configuration wherein a magnetic piston core1230is depicted away and in contact with a “hard” block valve end1220on a block valve1210respectively. Accordingly, as evident within second image1200B when the magnetic piston core1230is driven to one end of the FVSE the “hard” valve end1220butts against the piston core1230. In contrast, within third and fourth images1200G and1200H the magnetic piston core1230is depicted away from and in contact with a “soft” block valve end1240respectively. Accordingly, as evident within fourth image1200H when the magnetic piston core1230is driven to one end of the FVSE the “soft” block valve1240deforms under contact with the piston1230. “Soft” block valve end1240may be formed, for example, from an elastomer or rubber as may “hard” block valve end1220although with increased resiliency. Alternatively, “hard” block valve end1220may be formed from a suitable plastic, metal, ceramic or alloy.

Referring toFIG. 12Bthere are depict first to fourth images1200E to1200H. First and second images1200E and1200F depicted a first configuration wherein a magnetic piston core1230has a “soft” piston end portion1260away from and in contact with a “hard” block valve1250. Accordingly, as evident within second image1200F when the magnetic piston core1230is driven to one end of the FVSE the “soft” piston end1260deforms under contact with the “hard” block valve1250. In contrast, within third and fourth images1200G and1200H the magnetic piston core1230has a “hard” piston end1280which is depicted away from and in contact with a “soft” block valve end1270. Accordingly, as evident within fourth image1200H when the magnetic piston core1230is driven to one end of the FVSE the “soft” block valve1270deforms under contact with the “hard” piston end1280. “Soft” piston end portion1260and/or soft” block valve end1270may be formed, for example, from an elastomer or rubber whilst “hard” piston end1280may be formed from a suitable plastic, metal, ceramic or alloy.

Now referring toFIG. 13there are depicted perspective views in first and second cross-sections1300A and1300B respectively of LMMC fluidic valve/switch assembly variants of the module depicted inFIG. 1according to an embodiment of the invention. Within first cross-section1300A the FVSE is depicted within the FMSAM wherein the first piston1340engages “soft” elements1330which are formed upon the inner facing ends of a first left assembly body1350A and a first right assembly body1370A together with first magnet1310on the left hand end of the FVSE and second magnet1320on the right hand end of the FSVE. Accordingly, the module depicted in first cross-section1300A provides the block valve elements through the combination of the first left assembly body1350A with “soft” first elements1330and first right assembly body1370A with “soft” first elements1330but does so without the sheet of block valve elements. The “soft” first elements1330therefore provide a surface that conforms to the end face of the first piston1340when the piston is driven to each end of the FVSE/FVSAM. Accordingly, the FVSE geometry depicted in first cross-section1300A is similar to the geometry depicted in third and fourth images1200G and1200H ofFIG. 12B.

Within second cross-section1300B the first left assembly body1350A, first right assembly body1370A, first piston1340, and “soft” first elements1330are replaced with second left assembly body1350B, second right assembly body1370B, second piston1340, and “soft” second elements1380. Accordingly, the ends of the second piston1340are now covered with “soft” second elements1380and engage the “hard” inward facing portions of the second left assembly body1350B and second right assembly body1370B. Accordingly, the FVSE geometry depicted in second cross-section1300B is similar to the geometry depicted in first and second images1200E and1200F ofFIG. 12B.

Now referring toFIG. 14there is depicted a first cross-section view1400A of a LMMC fluidic valve/switch element according to an embodiment of the invention exploiting a piston1410with left and right profiled piston ends1420and1430respectively. These engage left and right block valve elements1440and1450respectively which extend the same distance into the bore of the FVSE. Accordingly, the different “stand-off” distances for the piston are now achieved through the left and right profiled piston ends1420and1430respectively engaging the left and right block valve elements1440and1450respectively. As depicted the piston1410comprises a molded body around a magnetic core1460. Also depicted inFIG. 14are second and third cross-section views1400B and1400C respectively along section lines Y-Y and Z-Z respectively which depict the inlet/outlet ports of the block valve1440and the end face of the piston1410.

Referring toFIG. 15there is depicted first and second cross-section views1500A and1500B respectively of a LMMC fluidic valve/switch element according to an embodiment of the invention exploiting profiled piston ends. In contrast toFIG. 14wherein the piston1410has a single projection on either end the piston1510has a pair of projections1520on the left hand end of the piston1510and a pair of second projections1530on the right hand end of the piston1510. The piston1510may be formed in a similar manner to the piston1410inFIG. 14in that it comprises a body surrounding a magnetic core, e.g. an injection molded plastic surrounding a magnetic core. Also depicted inFIG. 15are third and fourth cross-section views1500C and1500D respectively along section lines Y-Y and Z-Z respectively which depict the inlet/outlet ports of the block valve1540and the end face of the piston1510with the projections1520evident.

Whilst the projections on either of the left side and right side of the piston1510are depicted as being of equal length it would be evident that within other embodiments of the invention that one may project further than the other such that one port of the FVSE is blocked slightly earlier than the other as the piston engages that end of the FVSE. For example, the inlet may be blocked ahead of the outlet. Optionally, an end of a FVSE may comprise a pair of inlets and a pair of outlets and have multiple sets of projections such that as the piston moves to that end the inlets and outlets are closed off in a sequence defined by the projections. These projections may be “hard” to engage “soft” openings (ports) within the block valve or vice versa. Each inlet/outlet combination may feed to a different fluidic actuator, for example.

It would be evident that the piston1510inFIG. 15is orientated with the inlet/outlet ports within the block valve1540. Accordingly, the piston1540if circular as depicted requires orientating to the piston sleeve and block valves to ensure the first and second projections1520and1530align to the inlet/outlet ports on the block valve1540. Accordingly, as depicted inFIG. 16with first and second images1600A and1600B respectively the piston1610has projections1620that engage slots within the piston sleeve1630to orientate the piston1610within the piston sleeve1630. Alternatively, as depicted in third image1600C the piston1650may be elliptical within an elliptical bore of the piston sleeve1640. Optionally, other non-circularly symmetric cross-sections for the piston may be employed.

Now referring toFIG. 17there is depicted a cross-sectional view of a LMMC fluidic valve/switch element with increased magnetic retention according to an embodiment of the invention. The increased magnetic retention being achieved through the use of reduced diameter left and right magnetic washers1710and1740respectively in conjunction with the left and right gate valve elements1730and1760respectively within the left and right gate valve elements1720and1750respectively. The piston1780having left and right ends1770and1790respectively. Accordingly, as one the left hand side the piston1780position to the extreme is defined by the left end1770of the piston1780engaging the left gate valve element1730and left magnetic washer1720the left end1770may be “soft” rather than “hard” and hence formed from an elastomer or rubber, for example.

Now referring toFIG. 18there is depicted a cross-sectional view of a LMMC fluidic valve/switch element with increased magnetic retention according to an embodiment of the invention. In contrast to the designs described and depicted inFIGS. 2 to 17the left end motion of the piston1810is now stopped by a reduction in diameter of the piston sleeve1830at the end region1820. The gate valve stop1850of the gate valve1840is similarly “soft” and projects either to the same depth as the diameter reduction within the piston sleeve1830or slightly further such that the piston end1860compresses it and stops against the end of the piston sleeve1830. Optionally, rather than a diameter reduction at the end of the piston sleeve1830the “stop” is achieved through a projecting ring, projection or series of projections.

Now referring toFIG. 19there are depicted in first to fourth views1900A to1900D of an FVSE according to an embodiment of the invention with a different construction methodology wherein the valve elements are disposed inside the magnetic washers rather than through them from the outside of them. First and second images1900A and1900B depict two mutually perpendicular cross-sectional assembly perspective views of the FVSE. Within these a piston1960within a piston tube1950is clearly visible together with a pair of annular coils1930and an inner magnetic washer1940. It is also evident that the piston1960when at either end of the LMMC100contacts a non-magnetic washer1920and not an outer magnetic washer1910. Accordingly, where the non-magnetic washer1920is a block valve washer then the thickness of the non-magnetic washer(s)1920allows the magnetic retention force between the piston1960and the first magnetic washer1910to be adjusted when no power is applied to either of the annular coils1930. Alternatively, if the non-magnetic washer1920is a gate valve washer then the height of the projecting gate valve element from the body of non-magnetic washer into the FVSE bore adjusts the stop position of the piston1960.

It is also evident that fluid from an inlet which is coupled through aligned first openings within the magnetic washer1910and non-magnetic washer1920can be coupled to an outlet formed by the aligned second openings of the magnetic washer1910and non-magnetic washer1920via the region of the piston tube1950between the magnetic washer1910and non-magnetic washer1920and the end of the piston1960when the piston1960is moved away from the non-magnetic washer1920. When the piston1960moves to one end of the piston tube1950then its closes the connection between an inlet and outlet at one end of the LMMC100and opens the connection at the other end. When the piston1960moves to the other end then the closed connection is opened, and the open connection closed.

Referring to third and fourth images1900C and1900D ofFIG. 19Athere are depicted exploded assembly perspective and cross-sectional exploded assembly perspective views of the FVSE according to an embodiment of the invention. Accordingly, at either end there are first magnetic washers1910wherein each has a pair of openings separated by central element which is intended to align with a mating external assembly having first and second fluidic channels aligning to the pair of openings and separated by a central “wall” that aligns to the central element. Each outer magnetic washer1910abuts an annular coil1930. Disposed within the outermost end of each annular coil1930is a non-magnetic washer1920which has a pair of openings and central element aligned to those within the outer magnetic washers1910. Between the non-magnetic washers1920is piston tube1950within which the piston1960moves wherein the outer diameter of the piston tube1950is dimensioned to fit within the annular coils1930. Disposed around the piston tube1950between the annular coils1930is inner magnetic washer1940. Optionally, inner magnetic washer1940may be omitted from other embodiments of the invention.

In operation the piston is driven to one end or the other of the LMMC100under action of one or other or both annular coils1930which when electrically energized create a magnetic field acting upon the piston1960. However, once driven to one end of the other the annular coil(s)1930may be de-energized as the magnetic attraction between the first washer magnet1910and the piston1960maintains the piston in position against the non-magnetic washer1920. The magnetic force may be adjusted lower/higher by increasing/decreasing the thickness of the non-magnetic washer1920.

As discussed above in respect ofFIGS. 12A, 12B, and 13the non-magnetic washers may be “soft” or “hard” and engage with piston ends that are respectively “hard” and “soft.” Accordingly, within first image1900E inFIG. 19Bthe piston1960is depicted as core1970with piston ends1980. Accordingly, within an embodiment of the invention the piston ends1980may be “hard” and the non-magnetic washers1920“soft” whilst within another embodiment of the invention the piston ends1980may be “soft” and the non-magnetic washers1920“hard.” Alternatively, within another embodiment of the invention the piston ends1980may be “hard”, the non-magnetic washers1920“hard” but with “soft” gate valve elements or “soft” ends of block valve elements disposed towards the piston1960.

Within other embodiments of the invention one piston end may be “hard” and the other “soft.”

Within other embodiments of the invention where the LMMC fluidic element is employed as an oscillatory element such as a pump or vibratory actuator the fluidic block or gate valve elements may be “soft” as are the ends of the piston such that the piston when driven towards the valve element “impacts” and bounces back before a reverse electromagnetic field drives the piston towards the other end and it again bounces. In this manner the LMMC element oscillates but as the deceleration, stop and reverse motion of the piston at the end are derived through the soft elements the electromagnetic drive is only required during part of the cycle to move the piston partway along each reversal.

Within embodiments of the invention a block valve has been depicted as comprising an outer portion against the external surface of the magnetic washer and an inner portion comprising an outer ring with a central divider to form that portion of the pair of openings through the portion of the non-magnetic washer that projects through the magnetic washer into the bore of the FVSE and abuts the piston end. In contrast, a gate valve has been depicted as comprising an outer portion against the external surface of the magnetic washer and an inner portion comprising a central element that forms the pair of openings in conjunction with the piston sleeve within which the piston moves. However, it would be evident that a hybrid valve design may exploit a design similar to a block valve in that there is an outer ring and a central divider but the central divider projects further through the magnetic washer into the bore of the FVSE than the outer ring and abuts the piston end either solely or initially before the piston abuts both the outer ring and central divider.

Within the embodiments of the invention described above in respect ofFIGS. 1 to 19Bthe standoff has been primarily described as being different on one side of an FVSE and/or FVSAM to the other, e.g. the magnetic force required for holding a FVSE closed against a fluid source at zero pounds per square inch (0 psi) PSI source) is less than that required for a fluid source at, say, seven pounds per square inch (7 psi) and accordingly the separation between the magnetic piston and the magnetic washer can be larger for a FVSE operating on the 0 psi source than for one operating on the 7 psi source. Accordingly, the smaller the standoff distance from the magnet face to the inside face of the magnetic washer the larger the latching force and the more energy it takes to move the magnetic piston away from its latched position (all other aspects such a pressure difference etc. being equal).

Alternatively, the distances between the magnet face of the piston and the inner face of the magnetic washer may be the same but the dimensions of the magnetic washer may be adjusted to adjust the latching force for the same strength magnetic material. Alternatively, the magnetic material may be different at each end of the FVSE.

For example, rather than a 0.030″ (0.762 mm) thickness washer being employed on both ends of the FVSE a reduction in latching force can be achieved by reducing the magnetic washer thickness to 0.010″ (0.254 mm) or below.

Alternatively, the smaller the internal diameter of the magnetic washer the stronger the latching force although as this diameter reduces. However, as the internal diameter of the magnetic washer is reduced to less than that of the magnetic element of the piston then the smaller the openings to provide the inlet and outlet ports of the FVSE are as typically the outer diameter of the piston defines the inner diameter of piston sleeve. Similarly, as the inner diameter of the magnetic washer is increased beyond that of the magnetic element forming the piston then the latching force reduces. However, whilst increasing/decreasing the inner diameter of the magnetic washer adjusts the latching force it also adjusts the electrical drive efficiency of the electromagnetic coils in the same direction and hence whilst a reduction in latching force can be achieved then a corresponding reduction in the electrical efficiency of the FVSE in switching between states is observed.

Accordingly, a configuration with high latching force can be employed at either end of the FVSE and if required the latching force reduced by making the magnet relatively weak, either by selecting a different magnetic material for example or employing less magnetic material within a cast, molded, or stamped magnetic washer employing magnetic material within a body of one or more other materials. For example, using neodymium magnets may be formed at N26, N27, or N28 for reduced magnetic strength.

Within the embodiments of the invention described in respect ofFIGS. 1 to 19Bmagnetic washers are only employed at the ends of the piston sleeve and hence ends of the FVSE. However, within other embodiments of the invention a central washer is disposed between axially along the piston sleeve between the pair of electromagnetic coils. This central washer being formed, for example, from iron.

Within embodiments of the invention described in respect ofFIGS. 1 to 19BFVSEs have a switching speed typically in the range of 10 milliseconds (10 ms) or less depending upon the size of the FVSE, power, length of the piston travel, fluid viscosity etc. Accordingly, a typical “ON” and “OFF” cycle of a FVSE being driven from one end to the another and back (i.e. a FVSE with openings on either end so one end sees “ON” then “OFF” whilst the other end sees “OFF” and “ON”) would be typically under 30 milliseconds (30 ms). This switching cycle can accordingly achieve pulsed fluid actuations in the range of 30 Hz or higher. It would be evident that whilst there is not a significant fluid flow at these higher switching speeds the FVSE switching creates pressure and flow pulses at the control frequency and this pulsed pressure/flow can be employed to impart vibration to another portion of the fluidic system to which the FVSE is coupled such that the pressure/flow pulses act as a stimulation or vibration source for massagers, vibrators, etc.

Within the embodiments of the invention described in respect ofFIGS. 1 to 19BFVSEs have been described as comprising an outer shell. This may within some embodiments of the invention be formed from iron in order to provide magnetic shielding of an FVSE from external magnetic fields such as arising from other FVSEs within a FVSAM, for example. Alternatively, the outer shell may be formed from a suitable material such as a plastic to form protection/housing for the FVSE. Optionally, the electromagnetic coils etc. may be potted with a silicone or other suitable material wherein the outer shell provides a “holder” for the potting process and which is filled with the potting material. Optionally, the outer casing can overlap the washer such that the outer diameter of the washer is less than the inner diameter of the outer casing. Alternatively, the outer diameter of the outer sleeve may be the same as or less than the magnetic washers on either end so that the outer casing is capped by the magnetic washers.

Within the embodiments of the invention described in respect ofFIGS. 1 to 11 and 12 to 19BFVSEs have been described as employing a pair of coils in conjunction with a piston comprising a single axial magnetic element as depicted inFIG. 20Awherein first and second coils360and370are depicted with piston380in common withFIG. 3. However, within other embodiments of the invention the piston may be formed from a pair of shorter axial magnetic elements joined together with similar poles facing one another, e.g. north to north or south to south, with a thin layer of plastic or iron disposed between them yielding a piston therefore with a pair of externally facing south poles or north poles such that a single coil may be employed to drive the FVSE. Such a configuration being depicted inFIG. 20Bwherein a single coil2040is depicted around a piston2000comprising first magnet2010and second magnet2020disposed with side of a spacer2030. As depicted the first magnet2010has a north (N) pole on the left hand side (LHS) and south (S) pole on the right hand side (RHS) whilst the second magnet2020has a south (S) pole on the LHS and a north (N) pole on the RHS. Alternatively, the first magnet2010has a south (S) pole on the left hand side (LHS) and north (N) pole on the right hand side (RHS) whilst the second magnet2020has a north (N) pole on the LHS and a south (S) pole on the RHS.

It would also be evident that within other embodiments of the invention the underlying concept of a gasket engaging against the piston to seal the inlet/outlet ports of a FVSE as described and depicted in respect ofFIGS. 1 to 20Bmay be exploited with the valve inlet/outlet ports being blocked/opened by the side of the piston as it moves within the piston sleeve. Two examples of such configurations are depicted withinFIGS. 21A and 21Brespectively. WithinFIG. 21Aan FVSE2100A according to an embodiment of the invention is depicted comprising first and second coils2110and2120respectively together with a piston2130. Disposed at either end of the FVSE2100A on the sides of the FVSE2100A are ports2140which have gasket elements2170A on the inner surface of the FVSE2100A to engage against the sides of the piston2130as it moves from one end of the FVSE2100A to the other thereby blocking fluid flow from an inlet port2140to an outlet port2180or allowing fluid flow from an inlet port2140to an outlet port2180. As with the embodiments of the invention described supra the gasket elements2170A may be “hard” and engage a “soft” end of the piston2130(which is not depicted as comprising a magnetic core with soft ends for clarity) or they may be “soft” and engage “hard” ends of the piston2130(essentially the configuration depicted inFIG. 21Awith FVSE2100A). Disposed at each end of the FVSE are a non-magnetic spacer2150and magnetic washer2160wherein the thickness of the non-magnetic spacer2150may provide for the adjustment in stand-off distance between the magnetic washer2160and piston2130to adjust the latching force.

Referring toFIG. 21Bthere is depicted an FVSE2100B according to an embodiment of the invention comprising first and second coils2110and2120respectively together with the piston2130, non-magnetic spacer2150and magnetic washer2160. In this embodiment the gasket elements2170B project in from the exterior of the FVSE2100B. The addition inlet and outlet tubing depicted inFIG. 21Aas inlet port2140and outlet port2180with FVSE2100A are not depicted for clarity. As with FVSE2100A inFIG. 21Athe gasket elements2170B may be “hard” and engage a “soft” end of the piston2130(which is not depicted as comprising a magnetic core with soft ends for clarity) or they may be “soft” and engage “hard” ends of the piston2130(essentially the configuration depicted inFIG. 21Bwith FVSE2100B).

As embodiments of the invention for an FVSAM may exploit two or more FVSEs then it would be evident that these may be disposed within a linear one-dimensional (1D) or two-dimensional (2D) array comprising an array of bores within an outer body with a linear sheet of gasket material disposed along to provide the gasket elements2170A or2170B at each FVSE2100A or2100B within the array. With an FVSAM comprising FVSEs2100A the linear sheet of gasket material is inserted within the FVSAM prior to the non-magnetic spacers2150and magnetic washers2160being attached. These, it would be evident therefore, may be sheets applied across all FVSEs within the 1D or 2D array. However, with an FVSAM assembled exploiting FVSEs2100B it would be evident that the sheet of gasket material may be applied after assembly of the FVSEs within the FVSAM and then the assembled array of FVSEs may have assemblies applied either to each end or above and below to provide the fluidic inlet ports and outlet ports that couple to the remainder of the fluidic circuit that employs the FVSEs.

Within embodiments of the invention an outer sleeve, formed from a magnetic material, such as outer sleeve395inFIGS. 3 and 4respectively or outer sleeve795inFIGS. 7 and 8respectively may be omitted. In such embodiments the magnetic field from the coils extends further such that the FVSEs may experience crosstalk from other FVSEs within an FVSAM or from other sources of magnetic fields in the vicinity of the device comprising the FVSE(s).

Optionally, the magnetic elements, such as the magnet washer(s), piston or a magnetic core of a piston, may be an axial magnetized magnet formed from a powdered magnetic material embedded within one or more other materials which is then magnetized into what the inventor calls an axial magnetized magnet. The one or other materials provide the physical support for the magnetic material, e.g. ferromagnetic iron powder, and its shape etc. Such materials may include resins, thermoplastics, plastics, epoxies, low temperature glasses etc. Within another embodiment of the invention the piston may be formed from a laminated structure such that an alternating structure formed from layers of magnetic (or magnetizable) material are laminated with an electrically isolating material allowing Eddy currents within the piston to be suppressed. For example, thin magnetic discs may be stacked with thin plastic discs and potted/encapsulated within a casing or glued together/fused together. Optionally, the stacked structure may alternate along the length of the piston or it may be layer across the width of the piston. If non-uniform piston geometries are required, then these can be implemented during manufacturing through varying geometry piece-parts or through machining an assembled stack of materials or a combination of both. A powder based magnetic material may be embedded into a layer, followed by a layer without the material, followed by another layer with the magnetic material. The thickness of electrically isolating layers may be less than, equal to, or thicker than the layers with magnetic materials.

Optionally, the design of a piston may include magnetic materials, e.g. iron, to form caps at either end of an axially magnetised piston body or a laminated piston body or other piston in order to improve the magnetic flux density or “focus” the magnetic flux within the piston relative to the magnetic field within the coil without the piston.

It would be evident to one skilled in the art that the depictions of ECPUMPs and LMMCs in respect to embodiments of the invention within the descriptions and drawings have not shown or described the construction or interior configuration of the excitation coil or annular coil. The design and winding of such coils is known within the art and their omission has been for clarity of depiction of the remaining elements of the ECPUMPs and/or LMMCs. For example, the coil may be wound or formed upon a bobbin core and housed within bobbin case which includes an opening(s) for feeding the electrical wires in/out for connection to the external electrical drive and control circuit. Such coils may be wrapped and/or potted to encapsulate them. Examples of such coils include, for example, 170/22, 209/23, 216/24, 320/24, 352/24, 192/28 (e.g. 8 layers of 24 turns per layer), 234/28, 468/32, and 574/33. Each pair of numbers representing the number of windings and American wire gauge (AWG) of the wire employed. It would be evident that other designs may be employed without departing from the scope of the invention.